Glossary of Terms

used in Instrumentation of Solid Dosage Pharmaceutical Equipment

This document is intended to serve as a glossary of terminology applicable to software development and computerized systems in FDA regulated industries. It will facilitate consistency in describing the requirements of the law and regulations applicable to such products and systems. It is also a resource for investigators who conduct inspections and investigations involving software and computerized systems.

A - B - C - D - E - F - G - H - I - J - K - L  

M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z

Accuracy:

(MCC) The closeness with which a measurement approaches the true value of a variable being measured.

The use of the word "accurate" - free of error - in referring to a scientific observation or scientific method sometimes obscures the fact that even the best methods and observations are only use of the single word "accurate" also hides the fact that a relatively free from error. The number of separate elements contribute to over-all freedom from error. "Accurate" is frequently used to refer indiscriminately to the effect of any of these elements, or to the combined effects of all of them on the freedom from error of a system. Effective use of a method or observation requires that we know the ways and degrees to which the data are free of error, not that we know only that the data are "accurate" or "inaccurate".

The elements to be taken into account in a complete evaluation of a method or system can be derived from the properties of the quantitative relationship between the "input" and the "output" for the system. The input-output relationship, for all its generality, has specific application--and specific names--in different scientific fields and for different kinds of experimental or observational systems. In physics and engineering, the "stress-strain diagram" is a special representation of the input-output relationship; in pharmacology, the "dose-effect curve" is an example of the input-output relationship. In quantitative chemical analyses, the "calibration curve" is an example of the input-output relationship. Generally, "input" can be looked on as the measured value of an independent variable or "measured," "output" can be viewed as a measurement made under non-standard or test conditions.

"Accuracy", as formally defined, and the elements that contribute to it can be only briefly outlined here.

Accuracy

In engineering, "accuracy" is the ratio of the "error" of a system to the range of values for output that are possible, i.e., the ratio of error to so-called Full-Scale Output. Error is defined as the algebraic difference between an indicated output value and the true measure of the input or measured. Error, as defined by the engineer, is most like "precision" as defined below.

 

Validity

The degree to which output reflects what it purports to reflect, i.e., input; the degree to which output is a function of known input and it alone. For example, does an essay examination validly measure a student's knowledge of material, or is it invalid, actually measuring his literary skill or the state of the grader's digestion?

 

Reliability

The degree to which the input-output relationship is reproducible if the relationship is studied repeatedly under comparable conditions. For example, if a student took the same examination twice, or in two forms, would he get the same grade both times? If the same work were reviewed by two graders, would they both assign the same mark?

 

Sensitivity

The lowest value of input that can be inferred with a given degree of validity and reliability from measurements of output. Analogous to the usage for the word "threshold" is the phrase "threshold dose". The engineer uses the word "threshold", however, to mean the smallest change in input that will result in change in output.

 

Amplification

The amount of change in measured output per unit change in input. The slope of the input-output, or dose-effect, curve. (Engineers sometimes refer to "amplification" as "sensitivity".)

 

Precision

The capacity of the system to discriminate between different values of input; the "fineness" with which different values for input can be inferred from measured values of output. The pooled deviation of observed from expected values of output, all divided by the amplification, yields the "index of precision". The square of the reciprocal of the index of precision is the measure of the amount of information that can be delivered by the system.

Specifically, precision is computed in several steps. First, the deviation of each observed value of output from the corresponding predicted value is squared; predicted values are determined from the curve relating input and output for all the data. The squared deviations are summed and divided by N-2, the number of "degrees of freedom"; the square root of the quotient is determined and is a number analogous to the standard deviation. This "root mean square deviation" is then divided by the slope of the input-output curve, i.e., the amplification, to yield the "index of precision"; it is assumed that the input-output relationship is linear.

 

Comparability

The ability of a system to deliver data that can be compared in standard units of measurement and by standard statistical techniques with the data delivered by other systems. While not a critical component of accuracy, comparability of data generated by a system is critical to evaluating its accuracy and usefulness.

 

Economy

The ability of a system to deliver data of high information content at a low overall cost per item of data; economy does not, of course, contribute to "accuracy" but is an important determinant of the practical usefulness of a system or method.

ADC (A/D):
See analog-to-digital converter

address:

(FDA) (1) A number, character, or group of characters which identifies a given device or a storage location which may contain a piece of data or a program step. (2) To refer to a device or storage location by an identifying number, character, or group of characters.

AIM (Advanced Instrumentation Monitor):
(MCC) A PC based data acquisition system designed by Metropolitan Computing Corporation to collect and analyze signals from virtually any type of sensor to enable process monitoring of tablet presses, encapsulators, mixers-granulators, extruders, roller compactors, freeze dryers, and so on. It provides a plug-in compatibility with and can be moved between any instrumented equipment. Windows based state-of-the-art software is user friendly. AIM also features a Statistica\'99 based comprehensive experimental design section complete with response surface analysis, publication quality contour and 3-D plots, and on-line Tutorial.

(IEEE) (1) A finite set of well-defined rules for the solution of a problem in a finite number of steps. (2) Any sequence of operations for performing a specific task.

alphanumeric:
(FDA) Pertaining to a character set that contains letters, digits, and usually other characters such as punctuation marks.

(FDA) Address: 11 West 42nd Street, New York, N.Y. 10036. An organization that coordinates the development of U.S. voluntary national standards for nearly all industries. It is the U.S. member body to ISO and IEC. Information technology standards pertain to programming languages, electronic data interchange, telecommunications and physical properties of diskettes, cartridges and magnetic tapes.

amplifier:
(MCC) A device that is essential for any instrumentation to change the millivolt transducer output into volt range (amplification).  Strain gage amplifier also is used for adjusting reference voltage level so that the numerical value of a baseline will be reduced effectively to zero (bridge balancing).. Additional features of the amplifier may include excitation regulation and shunt calibration.

(MCC) The amount of change in measured output per unit change in input. The slope of the input-output, or dose-effect, curve. (Engineers sometimes refer to "amplification" as "sensitivity".)

 See "Accuracy" 

(FDA) Pertaining to data [signals] in the form of continuously variable [wave form] physical quantities; e.g., pressure, resistance, rotation, temperature, voltage. Contrast with digital.

(IEEE) A device that operates with variables represented by continuously measured quantities such as pressures, resistances, rotations, temperatures, and voltages.

(FDA) Input related devices which translate an input device's [sensor] analog signals to the corresponding digital signals needed by the computer. Contrast with DAC [digital-to-analog converter]. See: analog, digital.

(FDA) (1) To separate into elemental parts or basic principles so as to determine the nature of the whole. (2) A course of reasoning showing that a certain result is a consequence of assumed premises. (3) (ANSI) The methodical investigation of a problem, and the separation of the problem into smaller related units for further detailed study.

(IEEE) Anything observed in the documentation or operation of software that deviates from expectations based on previously verified software products or reference documents. See: bug, defect, error, exception, fault.

(IEEE) Software designed to fill specific needs of a user; for example, software for navigation, payroll, or process control. Contrast with support software; system software.

(IEEE) (1) The process of defining a collection of hardware and software components and their interfaces to establish the framework for the development of a computer system. See: functional design. (2) The result of the process in (1). See: software engineering.

(ISO) An historical copy of a database saved at a significant point in time for use in recovery or restoration of the database.

(IEEE) A lasting collection of computer system data or other records that are in long term storage.

The area under the plot of plasma concentration of drug (not logarithm of the concentration) against time after drug administration. The area is conveniently determined by the "trapezoidal rule": the data points are connected by straight line segments, perpendiculars are erected from the abscissa to each data point, and the sum of the areas of the triangles and trapezoids so constructed is computed. When the last measured concentration (C_n, at time t_n) is not zero, the AUC from t_n to infinite time is estimated by C_n/k_el.

The AUC is of particular use in estimating bioavailability of drugs, and in estimating total clearance of drugs (Cl_T). Following single intravenous doses, AUC = D/Cl_T, for single compartment systems obeying first-order elimination kinetics; alternatively, AUC = C₀/k_el. With routes other than the intravenous, for such systems, AUC = F · D/Cl_T, where F is the availability of the drug.

Cf. Clearance, Bioavailability, Compartments, F 

A timing independent method of electrical transfer of data in which the sending and receiving units are synchronized on each character, or small block of characters, usually by the use of start and stop signals. Contrast with synchronous transmission.

(1) (IEEE) An independent examination of a work product or set of work products to assess compliance with specifications, standards, contractual agreements, or other criteria. See: functional configuration audit, physical configuration audit. (2) (ANSI) To conduct an independent review and examination of system records and activities in order to test the adequacy and effectiveness of data security and data integrity procedures, to ensure compliance with established policy and operational procedures, and to recommend any necessary changes. See: computer system audit, software audit.

(1) (ISO) Data in the form of a logical path linking a sequence of events, used to trace the transactions that have affected the contents of a record. (2) A chronological record of system activities that is sufficient to enable the reconstruction, reviews, and examination of the sequence of environments and activities surrounding or leading to each event in the path of a transaction from its inception to output of final results.

See Bioavailability 

Range of frequencies used for transmitting a signal. A band can be identified by the difference between its lower and upper limits, i.e. bandwidth, as well as by its actual lower and upper limits; e.g., a 10 MHz band in the 100 to 110 MHz range.

The transmission capacity of a computer channel, communications line or bus. It is expressed in cycles per second [Hz], and also is often stated in bits or bytes per second. See: band.

(NIST) A specification or product that has been formally reviewed and agreed upon, that serves as the basis for further development, and that can be changed only through formal change control procedures.

(IEEE) Pertaining to a system or mode of operation in which inputs are collected and processed all at one time, rather than being processed as they arrive, and a job, once started, proceeds to completion without additional input or user interaction. Contrast with conversational, interactive, on-line, real time.

(MCC) A module of MCC AIM System that is suitable for producing a continuous batch record from such devices as roller compactors, kettles, extruders, fluid bed granulators, dryers, freeze dryers, and various other industry related equipment.

(FDA) The signalling rate of a line. It's the switching speed, or number of transitions [voltage or frequency change] made per second. At low speeds bauds are equal to bits per seconds; e.g., 300 baud is equal to 300 bps. However, one baud can be made to represent more than one bit per second.

(FDA) A measure of how closely the mean value in a series of replicate measurements approaches the true value. See: accuracy, precision, calibration.

The percent of dose entering the systemic circulation after administration of a given dosage form. More explicitly, the ratio of the amount of drug "absorbed" from a test formulation to the amount "absorbed" after administration of a standard formulation. Frequently, the "standard formulation" used in assessing bioavailability is the aqueous solution of the drug, given intravenously.

 The amount of drug absorbed is taken as a measure of the ability of the formulation to deliver drug to the sites of drug action; obviously - depending on such factors as disintegration and dissolution properties of the dosage form, and the rate of biotransformation relative to rate of absorption - dosage forms containing identical amounts of active drug may differ markedly in their abilities to make drug available, and therefore, in their abilities to permit the drug to manifest its expected pharmacodynamic and therapeutic properties.

 "Amount absorbed" is conventionally measured by one of two criteria, either the area under the time-plasma concentration curve (AUC) or the total (cumulative) amount of drug excreted in the urine following drug administration. A linear relationship exists between "area under the curve" and dose when the fraction of drug absorbed is independent of dose, and elimination rate (half-life) and volume of distribution are independent of dose and dosage form. Alinearity of the relationship between area under the curve and dose may occur if, for example, the absorption process is a saturable one, or if drug fails to reach the systemic circulation because of, e.g., binding of drug in the intestine or biotransformation in the liver during the drug's first transit through the portal system.

 Cf. F, Disintegration Time, Dissolution Time, Generic Drugs, Reference Standard, Equivalence, First Pass Effect, AUC 

The science and study of the ways in which the pharmaceutical formulation of administered agents can influence their pharmacodynamic and pharmacokinetic behavior. Differences in pharmaceutical properties can cause substantial differences in the biologic properties - and therapeutic usefulness - of preparations which are identical with respect to their content of active ingredient. Pharmaceutical properties known to influence the therapeutic efficacy of drugs include: appearance and taste of the dosage form, solubility of the drug form used in the preparation, the nature of "fillers", binders, or menstrua in the dosage form, particle size, stability of the active ingredient, age of the preparation, thickness and type of coating of a dosage form for oral administration, the presence of impurities, etc.

 Cf. Biotransformation, Biotranslocation, Pharmacokinetics, Bioavailability 

See: testing, functional

(ISO) (1) A string of records, words, or characters that for technical or logical purposes are treated as a unity. (2) A collection of contiguous records that are recorded as a unit, and the units are separated by interblock gaps. (3) A group of bits or digits that are transmitted as a unit and that may be encoded for error-control purposes. (4) In programming languages, a subdivision of a program that serves to group related statements, delimit routines, specify storage allocation, delineate the applicability of labels, or segment parts of the program for other purposes.

(NIST) A diagram of a system, instrument or computer, in which the principal parts are represented by suitably annotated geometrical figures to show both the basic functions of the parts and the functional relationships between them.

(FDA) A trojan horse which attacks a computer system upon the occurrence of a specific logical event [logic bomb], the occurrence of a specific time-related logical event [time bomb], or is hidden in electronic mail or data and is triggered when read in a certain way [letter bomb].

(1) (IEEE) To initialize a computer system by clearing memory and reloading the operating system. (2) To cause a computer system to reach a known beginning state. A boot program, in firmware, typically performs this function which includes loading basic instructions which tell the computer how to load programs into memory and how to begin executing those programs. A distinction can be made between a warm boot and a cold boot. A cold boot means starting the system from a powered-down state. A warm boot means restarting the computer while it is powered-up. Important differences between the two procedures are; 1) a power-up self-test, in which various portions of the hardware [such as memory] are tested for proper operation, is performed during a cold boot while a warm boot does not normally perform such self-tests, and 2) a warm boot does not clear all memory.

(FDA) A device or storage area [memory] used to store data temporarily to compensate for differences in rates of data flow, time of occurrence of events, or amounts of data that can be handled by the devices or processes involved in the transfer or use of the data.

(FDA) A fault in a program which causes the program to perform in an unintended or unanticipated manner. See: anomaly, defect, error, exception, fault.

(FDA) A common pathway along which data and control signals travel between different hardware devices within a computer system. (A) When bus architecture is used in a computer, the CPU, memory and peripheral equipment are interconnected through the bus. The bus is often divided into two channels, a control channel to select where data is located [address bus], and the other to transfer the data [data bus or I/O bus].

(FDA) Ensuring continuous adequate performance of sensing, measurement, and actuating equipment with regard to specified accuracy and precision requirements.

(MCC) A load value in engineering units that a transducer will indicate for each volt of output, after amplifier gain and balance. 

(FDA) The unit of a computer that includes the circuits controlling the interpretation of program instructions and their execution. The CPU controls the entire computer. It receives and sends data through input-output channels, retrieves data and programs from memory, and conducts mathematical and logical functions of a program.

(ANSI) In computer systems, a technical evaluation, made as part of and in support of the accreditation process, that establishes the extent to which a particular computer system or network design and implementation meet a prespecified set of requirements.

(FDA) The processes, authorities for, and procedures to be used for all changes that are made to the computerized system and/or the system's data. Change control is a vital subset of the Quality Assurance [QA] program within an establishment and should be clearly described in the establishment's SOPs.

See: configuration control

(MCC) A path that interconnects the components of computer and sensing devices, across which data and signals can be sent.

(FDA) A term used in a broad sense to describe the relationship between the receiver and the provider of a service. In the world of microcomputers, the term client-server describes a networked system where front-end applications, as the client, make service requests upon another networked system. Client-server relationships are defined primarily by software. In a local area network [LAN], the workstation is the client and the file server is the server. However, client-server systems are inherently more complex than file server systems. Two disparate programs must work in tandem, and there are many more decisions to make about separating data and processing between the client workstations and the database server. The database server encapsulates database files and indexes, restricts access, enforces security, and provides applications with a consistent interface to data via a data dictionary.

See: program, source code

(IEEE) An independent review of source code by a person, team, or tool to verify compliance with software design documentation and programming standards. Correctness and efficiency may also be evaluated. Contrast with code inspection, code review, code walkthrough.

(IEEE) A meeting at which software code is presented to project personnel, managers, users, customers, or other interested parties for comment or approval. Contrast with code audit, code inspection, code walkthrough.

(FDA) A compact disk used for the permanent storage of text, graphic or sound information. Digital data is represented very compactly by tiny holes that can be read by lasers attached to high resolution sensors. Capable of storing up to 680 MB of data, equivalent to 250,000 pages of text, or 20,000 medium resolution images. This storage media is often used for archival purposes.

(ANSI) The capability of a functional unit to meet the requirements of a specified interface.

(1) (IEEE) A computer program that translates programs expressed in a high-level language into their machine language equivalents. (2) The compiler takes the finished source code listing as input and outputs the machine code instructions that the computer must have to execute the program. See: assembler, interpreter, cross-assembler, cross-compiler.

The extent to which a patient agrees to and follows a prescribed treatment regimen.

 See Validation Compliance 

(IEEE) (1) A functional unit that can perform substantial computations, including numerous arithmetic operations, or logic operations, without human intervention during a run. (2) A functional programmable unit that consists of one or more associated processing units and peripheral equipment, that is controlled by internally stored programs, and that can perform substantial computations, including numerous arithmetic operations, or logic operations, without human intervention.

(ANSI) a functional unit, consisting of one or more computers and associated peripheral input and output devices, and associated software, that uses common storage for all or part of a program and also for all or part of the data necessary for the execution of the program; executes user-written or user-designated programs; performs user-designated data manipulation, including arithmetic operations and logic operations; and that can execute programs that modify themselves during their execution. A computer system may be a stand-alone unit or may consist of several interconnected units.

(ISO) An examination of the procedures used in a computer system to evaluate their effectiveness and correctness and to recommend improvements. See: software audit.

(FDA) Includes hardware, software, peripheral devices, personnel, and documentation; e.g., manuals and Standard Operating Procedures.

(IEEE) (1) The arrangement of a computer system or component as defined by the number, nature, and interconnections of its constituent parts. (2) In configuration management, the functional and physical characteristics of hardware or software as set forth in technical documentation or achieved in a product.

(IEEE) An element of configuration management, consisting of the evaluation, coordination, approval or disapproval, and implementation of changes to configuration items after formal establishment of their configuration identification.

See: change control

(IEEE) A discipline applying technical and administrative direction and surveillance to identify and document the functional and physical characteristics of a configuration item, control changes to those characteristics, record and report change processing and implementation status, and verifying compliance with specified requirements.

See: configuration control, change control, software engineering

(IEEE) The degree of uniformity, standardization, and freedom from contradiction among the documents or parts of a system or component. See: traceability.

(FDA) A value that does not change during processing. Contrast with variable.

(FDA) Hardware that controls peripheral devices such as a disk or display screen. It performs the physical data transfers between main memory and the peripheral device.

(IEEE) The degree to which software is free from faults in its specification, design and coding. The degree to which software, documentation and other items meet specified requirements. The degree to which software, documentation and other items meet user needs and expectations, whether specified or not.

(IEEE) The sudden and complete failure of a computer system or component.

(IEEE) A review conducted to verify that the detailed design of one or more configuration items satisfy specified requirements; to establish the compatibility among the configuration items and other items of equipment, facilities, software, and personnel; to assess risk areas for each configuration item; and, as applicable, to assess the results of producibility analyses, review preliminary hardware product specifications, evaluate preliminary test planning, and evaluate the adequacy of preliminary operation and support documents.

See: preliminary design review, system design review

(IEEE) Analysis which identifies all software requirements that have safety implications, and assigns a criticality level to each safety-critical requirement based upon the estimated risk.

(MCC) The change in transducer output occurring with time, while under load, and with all environmental conditions and other variables remaining constant. Usually measured with a rated load applied and expressed as a percent of rated output over a specific period of time.

(FDA) Representations of facts, concepts, or instructions in a manner suitable for communication, interpretation, or processing by humans or by automated means.

(IEEE) (1) Evaluation of the description and intended use of each data item in the software design to ensure the structure and intended use will not result in a hazard. Data structures are assessed for data dependencies that circumvent isolation, partitioning, data aliasing, and fault containment issues affecting safety, and the control or mitigation of hazards. (2) Evaluation of the data structure and usage in the code to ensure each is defined and used properly by the program. Usually performed in conjunction with logic analysis.

(IEEE) The degree to which a collection of data is complete, consistent, and accurate.

(1) (ISO) A process used to determine if data are inaccurate, incomplete, or unreasonable. The process may include format checks, completeness checks, check key tests, reasonableness checks and limit checks. (2) The checking of data for correctness or compliance with applicable standards, rules, and conventions.

(ANSI) A collection of interrelated data, often with controlled redundancy, organized according to a schema to serve one or more applications. The data are stored so that they can be used by different programs without concern for the data structure or organization. A common approach is used to add new data and to modify and retrieve existing data. See: archival database.

(Myers) Determining the exact nature and location of a program error, and fixing the error.

(FDA) Retrieve the information content from a modulated carrier wave; the reverse of modulate. Contrast with modulate.

(FDA) Converting signals from a wave form [analog] to pulse form [digital]. Contrast with modulation.

(FDA) A facet of reliability that relates to the degree of certainty that a system or component will operate correctly.

(IEEE) The process of defining the architecture, components, interfaces, and other characteristics of a system or component. See: architectural design, preliminary design, detailed design.

(IEEE) A document that describes the design of a system or component. Typical contents include system or component architecture, control logic, data structures, data flow, input/output formats, interface descriptions and algorithms. Synonym: design document. Contrast with specification, requirements.

See: software design description

(IEEE) The period of time in the software life cycle during which the designs for architecture, software components, interfaces, and data are created, documented, and verified to satisfy requirements.

(IEEE) A requirement that specifies or constrains the design of a system or system component.

(IEEE) A process or meeting during which a system, hardware, or software design is presented to project personnel, managers, users, customers, or other interested parties for comment or approval. Types include critical design review, preliminary design review, system design review.

See: specification, design

(IEEE) (1) The process of refining and expanding the preliminary design of a system or component to the extent that the design is sufficiently complete to be implemented.

See: software development process.

(ANSI) A systematic approach to software creation that defines development phases and specifies the activities, products, verification procedures, and completion criteria for each phase.

See: incremental development, rapid prototyping, spiral model, waterfall model

(IEEE) Pertaining to the detection and isolation of faults or failures. For example, a diagnostic message, a diagnostic manual.

Pertaining to data [signals] in the form of discrete [separate/pulse form] integral values. Contrast with analog.

Output related devices which translate a computer's digital outputs to the corresponding analog signals needed by an output device such as an actuator. Contrast with ADC [Analog-to-Digital Converter].

Circular rotating magnetic storage hardware. Disks can be hard [fixed] or flexible [removable] and different sizes.

Hardware used to read from or write to a disk or diskette.

An operating system program; e.g., DR-DOS from Digital Research, MS-DOS from Microsoft Corp., OS/2 from IBM, PC-DOS from IBM, System-7 from Apple.

A floppy [flexible] disk.

(MCC) The time required for a tablet to break up into granules of specified size (or smaller), under carefully specified test conditions. The conditions of the laboratory test, in vitro, are set to simulate those which obtain in vivo. Factors such as the kind and amount of tablet binders and the degree of compression used in compacting the tablet ingredients help determine disintegration time. The active ingredients in a disintegrated tablet are not necessarily found to be in solution and available for absorption. A long disintegration time is incompatible with rapid drug absorption; a short disintegration time, by itself, does not ensure rapid absorption.

 Cf. Dissolution Time, Generic Drugs, Biopharmaceutics 

(MCC) The time required for a given amount (or fraction) of drug to be released into solution from a solid dosage form. Dissolution time is measured in vitro, under conditions which simulate those which occur in vivo, in experiments in which the amount of drug in solution is determined as a function of time. Needless to say, the availability of a drug in solution - rather than as part of insoluble particulate matter - is a necessary preliminary to the drug's absorption.

 Cf. Disintegration Time, Physiological Availability, Generic Drug, Biopharmaceutics 

(ANSI) The aids provided for the understanding of the structure and intended uses of an information system or its components, such as flowcharts, textual material, and user manuals.

(NIST) Technical data or information, including computer listings and printouts, in human readable form, that describe or specify the design or details, explain the capabilities, or provide operating instructions for using the software to obtain desired results from a software system.

(MCC) The physical state in which a drug is dispensed for use. For example: a frequent dosage form of procaine is a sterile solution of procaine. The most frequent dosage form of aspirin is a tablet. 

(MCC) The quantity of drug, or dosage form, administered to a subject at a given time; for example, the usual dose of aspirin for relief of pain in an adult is 300-600 milligrams. Dose may be expressed in terms appropriate to a specific dosage form, i.e., one teaspoonful of a liquid medication, rather than the weight of drug in the teaspoonful. Dose may be described as an absolute dose(the total amount administered to a subject) or as a relative dose (relative to some property of the subject as body weight or surface area, mgm/kg, or mgm/m²).

 Cf. Dosage, Multiple Dose Regimens 

(ISO) The unwanted change of the value of an output signal of a device over a period of time when the values of all input signals to the device are kept constant.

(FDA) A program that links a peripheral device or internal function to the operating system, and providing for activation of all device functions.

(MCC) A chemical used in the diagnosis, treatment, or prevention of disease. More generally, a chemical, which, in a solution of sufficient concentration, will modify the behavior of cells exposed to the solution. Drugs produce only quantitative changes in the behavior of cells; i.e., drugs increase or decrease the magnitude, frequency, of duration of the normal activities of cells. Drugs used in therapy never produce qualitative changes in cell behavior short of producing death of the cell, e.g., a nerve cell cannot be made to contract or a muscle cell cannot be made to secrete saliva by use of a drug. The degree to which this point of view will be modified by the discovery and development of agents which can cause mutations of cells remains to be seen. 

-E-

See Effective 

(FDA) A device which has its own computing power dedicated to specific functions, usually consisting of a microprocessor and firmware. The computer becomes an integral part of the device as opposed to devices which are controlled by an independent, stand-alone computer. It implies software that integrates operating system and application functions.

(IEEE) Software that is part of a larger system and performs some of the requirements of that system; e.g., software used in an aircraft or rapid transit system. Such software does not provide an interface with the user.

(IEEE) A software development technique that consists of isolating a system function or a set of data and the operations on those data within a module and providing precise specifications for the module.

(ANSI) (1) A person, device, program, or computer system that uses an information system for the purpose of data processing in information exchange. (2) A person whose occupation requires the use of an information system but does not require any knowledge of computers or computer programming.

(ISO) A discrepancy between a computed, observed, or measured value or condition and the true, specified, or theoretically correct value or condition. See: anomaly, bug, defect, exception, fault.

See: debugging, failure analysis

(FDA) Techniques used to identify errors in data transfers. See: check summation, cyclic redundancy check [CRC], parity check, longitudinal redundancy.

(IEEE) An event that causes suspension of normal program execution. Types include addressing exception, data exception, operation exception, overflow exception, protection exception, underflow exception.

The voltage applied to the input terminals of a strain gage bridge.

See Bioassay, Cross-Over Experiment, Blind Experiment 

(IEEE) A system or component that automatically places itself in a safe operational mode in the event of a failure.

(IEEE) The inability of a system or component to perform its required functions within specified performance requirements. See: bug, crash, exception, fault.

(FDA) Determining the exact nature and location of a program error in order to fix the error, to identify and fix other similar errors, and to initiate corrective action to prevent future occurrences of this type of error. Contrast with debugging.

(FDA) An incorrect step, process, or data definition in a computer program which causes the program to perform in an unintended or unanticipated manner. See: anomaly, bug, defect, error, exception.

(1) (ISO) On a data medium or in storage, a specified area used for a particular class of data; e.g., a group of character positions used to enter or display wage rates on a screen. (2) Defined logical data that is part of a record. (3) The elementary unit of a record that may contain a data item, a data aggregate, a pointer, or a link. (4) A discrete location in a database that contains an unique piece of information. A field is a component of a record. A record is a component of a database.

(1) (ISO) A set of related records treated as a unit; e.g., in stock control, a file could consists of a set of invoices. (2) The largest unit of storage structure that consists of a named collection of all occurrences in a database of records of a particular record type.

(IEEE) A variable that is set to a prescribed state, often "true" or "false", based on the results of a process or the occurrence of a specified condition.

See: diskette

(2) (ISO) A graphical representation in which symbols are used to represent such things as operations, data, flow direction, and equipment, for the definition, analysis, or solution of a problem. (2) (IEEE) A control flow diagram in which suitably annotated geometrical figures are used to represent operations, data, or equipment, and arrows are used to indicate the sequential flow from one to another.

An agency of the Department of Health, and Human Services which is responsible for ensuring compliance with the amended federal Food, Drug and Cosmetic Act. This agency must pass judgement on the safety of drugs, the labels affixed to drug packages, and all printed material accompanying a packaged drug before that drug may be introduced to interstate commerce. The law empowers the F.D.A. to pass on the efficacy of a new drug or pharmaceutical preparation and gives the agency ultimate jurisdiction over the clinical testing of a drug before it is approved for general sale and use. Prosecution of violation of the F.D. and C. Act is carried out by the Attorney General's Office on recommendation of the F.D.A.

 Cf. U.S.P., Harrison Narcotic Act, Effective 

The greatest load a piece of equipment is designed to carry under specified conditions. Also known as rated load.

The total interval over which an instrument is intended to be operated. Also, the output from a transducer when the maximum rated stimulus is applied to the input.

Drug formulations of identical composition with respect to the active ingredient, i.e., drugs that meet current official standards of identity, purity, and quality of active ingredient. Drug dosage forms considered as "generically equivalent" are more properly considered as "chemically equivalent" in that they contain a designated quantity of drug chemical in specified stable condition and meet pharmacopoeial requirements for chemical and physical properties.

Each of a number of preparations of a given drug entity may carry a different "proprietary name" or "trademark"; such a name is registered with the U.S. Patent Office and identifies the special brand of the drug with the firm owning the name. All such preparations - identical with respect to content and specification of active ingredient - may be looked upon as comprising a "genus"; they are generically equivalent and are generic drugs.

It is well recognized that a number of factors other than quantity of drug present in a dose can determine the ultimate therapeutic usefulness of the drug preparation, and even the availability of drug to the site of action once the preparation has been given. Drugs may be generically equivalent but not therapeutically equivalent. Factors which affect therapeutic usefulness or efficacy of drug preparations include appearance, taste, disintegration and dissolution properties of the preparation, interaction of active materials with other ingredients including binders and solvents, pH, particle size, age of preparation, conditions of manufacture such as degree of tablet compression, and the nature and amount of coating of enteric-coated tablets.
 

 Cf. Biopharmaceutics, United States Pharmacopoeia, Bioavailability, Equivalence  

Approximately one billion bytes; precisely 230 or 1,073,741,824 bytes.

(IEEE) A diagram or other representation consisting of a finite set of nodes and internode connections called edges or arcs. Contrast with blueprint. See: block diagram, box diagram, bubble chart, call graph, cause-effect graph, control flow diagram, data flow diagram, directed graph, flowchart, input-process-output chart, structure chart, transaction flowgraph.

Documents such as charts, diagrams, graphs which depict program structure, states of data, control, transaction flow, HIPO, and cause-effect relationships; and tables including truth, decision, event, state-transition, module interface, exception conditions/responses necessary to establish design integrity.

An interlocked sequence of signals between connected components in which each component waits for the acknowledgement of its previous signal before proceeding with its action, such as data transfer.

Printed, etc., output on paper.

Hardware used to read from or write to a hard disk.

(ISO) Physical equipment, as opposed to programs, procedures, rules, and associated documentation. Contrast with software.

A unit of frequency equal to one cycle per second.

The maximum difference between transducer output readings for the same applied load. One reading is obtained by increasing the load from zero and the other reading is obtained by decreasing the load from full scale (rated) load. Measurements should be taken as rapidly as possible to minimize creep.

A manual testing technique in which program documents [specifications (requirements, design), source code or user's manuals] are examined in a very formal and disciplined manner to discover errors, violations of standards and other problems. Checklists are a typical vehicle used in accomplishing this technique.

(ANSI) The phase in the system life cycle that includes assembly and testing of the hardware and software of a computerized system. Installation includes installing a new computer system, new software or hardware, or otherwise modifying the current system.

(IEEE) The period of time in the software life cycle during which a software product is integrated into its operational environment and tested in this environment to ensure that it performs as required.

(MCC)

(1)(MCC) Strain gauge, piezoelectric transducers, or various sensing devices installed on tablet presses or other manufacturing process equipment that convert forces into voltage. Other types of instrumentation measure torque, temperature, pressure, level, speed, and other engineering forces. (2)(NBS) The insertion of additional code into a program in order to collect information about program behavior during program execution. Useful for dynamic analysis techniques such as assertion checking, coverage analysis, tuning.

(IEEE) Pertaining to a system or mode of operation in which each user entry causes a response from or action by the system. Contrast with batch.

(1) (ISO) A shared boundary between two functional units, defined by functional characteristics, common physical interconnection characteristics, signal characteristics, and other characteristics, as appropriate. The concept involves the specification of the connection of two devices having different functions. (2) A point of communication between two or more processes, persons, or other physical entities. (3) A peripheral device which permits two or more devices to communicate.

(1) The suspension of a process to handle an event external to the process. (2) A technique to notify the CPU that a peripheral device needs service, i.e., the device has data for the processor or the device is awaiting data from the processor. The device sends a signal, called an interrupt, to the processor. The processor interrupts its current program, stores its current operating conditions, and executes a program to service the device sending the interrupt. After the device is serviced, the processor restores its previous operating conditions and continues executing the interrupted program. A method for handling constantly changing data. Contrast with polling.

(IEEE) A user-defined unit of work that is to be accomplished by a computer. For example, the compilation, loading, and execution of a computer program. See: job control language.

Approximately one thousand bytes. This symbol is used to describe the size of computer memory or disk storage space. Because computers use a binary number system, a kilobyte is precisely 210 or 1024 bytes.

A strain gage bridge in an enclosure forming a complete transducer device which produces an output signal proportional to the applied load. MCC load cells are calibrated NIST traceable.

A communications network that serves users within a confined geographical area. It is made up of servers, workstations, a network operating system, and a communications link.

(IEEE) In software engineering, a predefined sequence of computer instructions that is inserted into a program, usually during assembly or compilation, at each place that its corresponding macroinstruction appears in the program.

(FDA) A non-moving storage device utilizing one of a number of types of electronic circuitry to store information.

(IEEE) A software component that is called by the operating system of a computer and that usually calls other software components.

(IEEE) The ease with which a software system or component can be modified to correct faults, improve performance or other attributes, or adapt to a changed environment.

(QA) Activities such as adjusting, cleaning, modifying, overhauling equipment to assure performance in accordance with requirements. Maintenance to a software system includes correcting software errors, adapting software to a new environment, or making enhancements to software.

(IEEE) A quantitative assessment of the degree to which a software product or process possesses a given attribute.

The process of determining the value of some quantity in terms of a standard unit.

Approximately one million bytes. Precisely 1024 K Bytes, 220 bytes, or 1,048,576 bytes.

A unit of frequency equal to one million cycles per second.

Any device or recording medium into which binary data can be stored and held, and from which the entire original data can be retrieved. The two types of memory are main; e.g., ROM, RAM, and auxiliary; e.g., tape, disk.

A computer display listing a number of options; e.g., functions, from which the operator may select one. Sometimes used to denote a list of programs.

A module of the MCC AIM System designed for recording and analyzing signals from high shear, planetary and other types of mixers. MGM is especially effective where there is a substantial change in viscous properties of the mix. End point determination is facilitated by means of digital smoothing of power and torque signals, along with real time calculation of time derivatives and signal representation in frequency domain.

(FDA) A symbol chosen to assist human memory and understanding; e.g., an abbreviation such as "MPY" for multiply.

Construction of programs used to model the effects of a postulated environment for investigating the dimensions of a problem for the effects of algorithmic processes on responsive targets.

(ISO) A functional unit that modulates and demodulates signals. One of the functions of a modem is to enable digital data to be transmitted over analog transmission facilities. The term is a contraction of modulator-demodulator.

Using a modem to communicate between computers. MODEM access is often used between a remote location and a computer that has a master database and applications software, the host computer.

(IEEE) Software composed of discrete parts.

Varying the characteristics of a wave in accordance with another wave or signal, usually to make user equipment signals compatible with communication facilities.

(1) (MCC) Modification of amplitude of a waveform (carrier) varying in step with the instantaneous value of another wave (signal). (2) (FDA) Converting signals from a binary-digit pattern [pulse form] to a continuous wave form [analog].

(MCC) In an amplitude modulated wave, the ratio of half the difference between the maximum and minimum amplitudes to the average amplitude (in percent).

(IEEE) A mode of operation in which two or more tasks are executed in an interleaved manner. Synonym: parallel processing.

(FDA) Gaithersburg, MD 20899. A federal agency under the Department of Commerce, originally established by an act of Congress on March 3, 1901 as the National Bureau of Standards. The Institute's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. The National Computer Systems Laboratory conducts research and provides, among other things, the technical foundation for computer related policies of the Federal Government.

(1) (ISO) An arrangement of nodes and interconnecting branches. (2) A system [transmission channels and supporting hardware and software] that connects several remotely located computers via telecommunications.

(MCC) The designed normal maximum transducer capacity. The sensitivity of a transducer is based on this capacity.

(MCC) The maximum deviation of the calibration points from a regression line (best fit to the data), expressed as a percentage of the full scale (rated) output and measured on increasing load only.

(IEEE) Pertaining to a system or mode of operation in which input data enter the computer directly from the point of origin or output data are transmitted directly to the point where they are used. For example, an airline reservation system. Contrast with batch.

(ISO) Software that controls the execution of programs, and that provides services such as resource allocation, scheduling, input/output control, and data management. Usually, operating systems are predominantly software, but partial or complete hardware implementations are possible.

(IEEE) The period of time in the software life cycle during which a software product is employed in its operational environment, monitored for satisfactory performance, and modified as necessary to correct problems or to respond to changing requirements.

One of the elements of an experiment which can be varied, but which the experimenter tries to control or maintain constant during the course of a specific experiment, while intentionally altering the independent variable and observing changes in the dependent variable. Parameters in one experiment (stimulus strength, for example) might well be independent variables in another.

Originally, the variable elements or terms of an equation that determine the overall position within the axes of the line or figure described by the equation; to be contrasted with the independent variable, specific values for which are uniquely related to specific values of the dependent variable. Constants or invariants always have the same value, in whatever equation they occur. In the equation Y = e^(a-bX), X is the independent variable, Y is the dependent variable, e (the base of the system of natural logarithms: 2.7182+) is a constant, and a and b are parameters.

 Cf. Metameter, Bioassay 

(ISO) A character string that enables a user to have full or limited access to a system or to a set of data.

(IEEE) A sequence of instructions that may be performed in the execution of a computer program.

(IEEE) A requirement that imposes conditions on a functional requirement; e.g., a requirement that specifies the speed, accuracy, or memory usage with which a given function must be performed.

(FDA) Equipment that is directly connected a computer. A peripheral device can be used to input data; e.g., keypad, bar code reader, transducer, laboratory test equipment; or to output data; e.g., printer, disk drive, video system, tape drive, valve controller, motor controller.

(FDA) Synonymous with microcomputer, a computer that is functionally similar to large computers, but serves only one user.

(Gr. Pharmakon - drug, and Logos - word) is the study of drugs in all their aspects. Pharmacy, although often confused with pharmacology, is, in fact, an independent discipline concerned with the art and science of the preparation, compounding, and dispensing of drugs. Pharmacognosy is a branch of pharmacy which deals with the identification and analysis of the plant and animal tissues from which drugs may be extracted. Pharmacodynamics, which in common usage is usually termed "pharmacology", is concerned with the study of drug effects and how they are produced. The pharmacodynamicist, or pharmacologist, identifies the effects produced by drugs, and determines the sites and mechanisms of their action in the body. The pharmacologist studies the physiological or biochemical mechanisms by which drug actions are produced. The pharmacologist also investigates those factors which modify the effects of drugs, i.e. the routes of administration, influence of rates of absorption, differential distribution, and the body's mechanisms of excretion and detoxification, on the total effect of a drug. Pharmacotherapeutics is the study of the use of drugs in the diagnosis, prevention, and treatment of disease states. Toxicology is the study of drug effects which are inimical to health. The toxicologist may investigate such diverse problems as the effects of overdoses of pharmacotherapeutic agents; the diagnosis, treatment, and prevention of lead poisoning in the paint manufacturing industry; the possibility that criminal poisoning was the cause of an otherwise inexplicable death, etc.

"Experimental pharmacology, in the broadest sense, deals with the reactions of living organisms to chemical agents, or, to put the matter in another way, the behavior of organisms to changes in the chemical environment in which they live. Pharmacology is a part of biology. . . . Of all the vast number of pharmacologic reactions, those which the physician attempts to use for curative purposes are of the greatest interest and most deserved of study. This part of pharmacology, the scientific knowledge of remedial agents, forms the theoretical foundation for therapeutics..." H.H.Meter and R. Gottlieb, Experimental Pharmacology as a Basis for Therapeutics: A Textbook for Students and Physicians, 1910 (trans. by V. E. Henderson).

(IEEE) (1) In image processing and pattern recognition, the smallest element of a digital image that can be assigned a gray level. (2) In computer graphics, the smallest element of a display surface that can be assigned independent characteristics. This term is derived from the term "picture element".

(1) (MCC) Mixture of powdered ingredients of non-specific nature used for testing of equipment purposes only. (2) (Latin: I will satisfy). "A medicine or preparation with no inherent pertinent pharmacologic activity which is effective only by virtue of the factor of suggestion attendant upon its administration."

 Cf. Dummy, Negative Control Drug, Positive Control Drug 

A special case of synergy (q.v.) in which the simultaneous effects of two or more drugs is greater than the sum of the independent effects of these drugs. For example. although physostigmine has no acetylcholine-like activity of its own, it potentiates the actions of acetylcholine by inhibiting the enzymes responsible for the destruction of acetylcholine. Intensity of effect may be potentiated, duration of effect may be prolonged: potentiation and prolongation are independent phenomena, but frequently occur together.

 Cf. Synergy, Antagonism 

(MCC) Describes reproducibility of a measurement, i.e. how much successive readings of the same fixed value of a variable differ from one another.

The capacity of the system to discriminate between different values of input; the "fineness" with which different values for input can be inferred from measured values of output. The pooled deviation of observed from expected values of output, all divided by the amplification, yields the "index of precision". The square of the reciprocal of the index of precision is the measure of the amount of information that can be delivered by the system.

Specifically, precision is computed in several steps. First, the deviation of each observed value of output from the corresponding predicted value is squared; predicted values are determined from the curve relating input and output for all the data. The squared deviations are summed and divided by N-2, the number of "degrees of freedom"; the square root of the quotient is determined and is a number analogous to the standard deviation. This "root mean square deviation" is then divided by the slope of the input-output curve, i.e., the amplification, to yield the "index of precision"; it is assumed that the input-output relationship is linear.

 See Accuracy  

(IEEE) (1) The process of analyzing design alternatives and defining the architecture, components, interfaces, and timing and sizing estimates for a system or component.

(IEEE) A review conducted to evaluate the progress, technical adequacy, and risk resolution of the selected design approach for one or more configuration items; to determine each design's compatibility with the requirements for the configuration item; to evaluate the degree of definition and assess the technical risk associated with the selected manufacturing methods and processes; to establish the existence and compatibility of the physical and functional interfaces among the configuration items and other items of equipment, facilities, software and personnel; and, as applicable, to evaluate the preliminary operational and support documents.

(1) (ISO) A sequence of instructions suitable for processing. Processing may include the use of an assembler, a compiler, an interpreter, or another translator to prepare the program for execution. The instructions may include statements and necessary declarations. (2) (ISO) To design, write, and test programs. (3) (ANSI) In programming languages, a set of one or more interrelated modules capable of being executed. (4) Loosely, a routine. (5) Loosely, to write a routine.

(ISO) A set of semantic and syntactic rules that determines the behavior of functional units in achieving communication.

(MCC) A proximity switch (transducer) is a non-contact electromagnetic pickup device that senses the presence or absence of metal. It is installed on the press in order to mark the beginning of a turret revolution and thus enable station identification by system software.

(FDA) Establishing confidence that process equipment and ancillary systems are compliant with appropriate codes and approved design intentions, and that manufacturer's recommendations are suitably considered.

(FDA) Establishing confidence that process equipment and sub-systems are capable of consistently operating within established limits and tolerances.

(FDA) Establishing confidence that the process is effective and reproducible.

(FDA) Establishing confidence through appropriate testing that the finished product produced by a specified process meets all release requirements for functionality and safety.

(MCC) Testing completed at installation of AIM System proving proper function of all related hardware and software.

(1) (ISO) The planned systematic activities necessary to ensure that a component, module, or system conforms to established technical requirements. (2) All actions that are taken to ensure that a development organization delivers products that meet performance requirements and adhere to standards and procedures. (3) The policy, procedures, and systematic actions established in an enterprise for the purpose of providing and maintaining some degree of confidence in data integrity and accuracy throughout the life cycle of the data, which includes input, update, manipulation, and output. (4) (QA) The actions, planned and performed, to provide confidence that all systems and components that influence the quality of the product are working as expected individually and collectively.

(IEEE) (1) A planned and systematic pattern of all actions necessary to provide adequate confidence that an item or product conforms to established technical requirements. (2) A set of activities designed to evaluate the process by which products are developed or manufactured.

The operational techniques and procedures used to achieve quality requirements.

See Full Scale

Chips which can be called read/write memory, since the data stored in them may be read or new data may be written into any memory address on these chips. The term random access means that each memory location [usually 8 bits or 1 byte] may be directly accessed [read from or written to] at random. This contrasts to devices like magnetic tape where each section of the tape must be searched sequentially by the read/write head from its current location until it finds the desired location. ROM memory is also random access memory, but they are read only not read/write memories. Another difference between RAM and ROM is that RAM is volatile, i.e. it must have a constant supply of power or the stored data will be lost.

See Full Scale

A memory chip from which data can only be read by the CPU. The CPU may not store data to this memory. The advantage of ROM over RAM is that ROM does not require power to retain its program. This advantage applies to all types of ROM chips; ROM, PROM, EPROM, and EEPROM.

(IEEE) Pertaining to a system or mode of operation in which computation is performed during the actual time that an external process occurs, in order that the computation results can be used to control, monitor, or respond in a timely manner to the external process. Contrast with batch.

A fast-response [immediate response] on-line system which obtains data from an activity or a physical process, performs computations, and returns a response rapidly enough to affect [control] the outcome of the activity or process; e.g., a process control application.

(1) (ISO) a group of related data elements treated as a unit. [A data element (field) is a component of a record, a record is a component of a file (database)].

A drug, chemical, or dosage form, etc., of specified properties used as the basis for quantitative comparison with other materials of qualitatively similar properties. The purpose of such a comparison is to express the amount or degree of the designated property in the "other" material as a fraction or multiple of the amount or degree of the property contained in the standard. The reference standard serves as a unit of measurement for the properties of the other, or "unknown," material.

Even physical systems of measurement are based on reference standards. The use of reference standards is of particularly great importance to the design and interpretation of biological experiments. In biological experiments, particularly, variability and instability of the biological test system can markedly influence the apparent effects and effectiveness of substances being tested. 

(MCC) The degree to which the input-output relationship is reproducible if the relationship is studied repeatedly under comparable conditions. For example, if a student took the same examination twice, or in two forms, would he get the same grade both times? If the same work were reviewed by two graders, would they both assign the same mark?

 See Accuracy. 

(MCC) The maximum difference between transducer output readings for repeated applied loads under identical loading and environmental conditions. The ability of an instrument to give identical results in successive instances.

(IEEE) (1) A condition or capability needed by a user to solve a problem or achieve an objective. (2) A condition or capability that must be met or possessed by a system or system component to satisfy a contract, standard, specification, or other formally imposed documents. (3) A documented representation of a condition or capability as in (1) or (2).

(IEEE) The period of time in the software life cycle during which the requirements, such as functional and performance capabilities for a software product, are defined and documented.

(IEEE) A process or meeting during which the requirements for a system, hardware item, or software item are presented to project personnel, managers, users, customers, or other interested parties for comment or approval. Types include system requirements review, software requirements review. Contrast with code review, design review, formal qualification review, test readiness review.

(MCC) The smallest change in measured value that the instrument can detect.

(FDA) Relative to software changes, revalidation means validating the change itself, assessing the nature of the change to determine potential ripple effects, and performing the necessary regression testing.

(IEEE) A process or meeting during which a work product or set of work products, is presented to project personnel, managers, users, customers, or other interested parties for comment or approval. Types include code review, design review, formal qualification review, requirements review, test readiness review. Contrast with audit, inspection.

See: version number

(FDA) The degree to which a software system or component can function correctly in the presence of invalid inputs or stressful environmental conditions.

(DOD) Freedom from those conditions that can cause death, injury, occupational illness, or damage to or loss of equipment or property, or damage to the environment.

A peripheral input device which senses some variable in the system environment, such as temperature, and converts it to an electrical signal which can be further converted to a digital signal for processing by the computer.

A high speed computer in a network that is shared by multiple users. It holds the programs and data that are shared by all users.

(MCC) The ratio of a change in measurement value to a change in measured variable. For example, if you ate a 1 lb. steak and your bathroom scale shows 2 lb. increase in your body weight, you can call the scale insensitive (ratio is far from unity).

The ability of a population, an individual or a tissue, relative to the abilities of others, to respond in a qualitatively normal fashion to a particular drug dose. The smaller the dose required to produce an effect, the more sensitive is the responding system. A patient would be considered abnormally sensitive to aspirin if a small fraction of the normal analgesic dose gave adequate pain relief; or, were an abnormally large dose of aspirin required to afford pain relief, the subject would be said to be "insensitive" to aspirin. Conversely, the drug would appear to be extraordinarily potent or impotent in such a patient. If a patient manifested an allergic response after raking aspirin, he would be considered hypersensitive to aspirin, regardless of whether the aspirin afforded him relief from pain, and regardless of the size of the dose required to elicit the allergic response. Such a patient might be simultaneously hypersensitive to aspirin, and insensitive to aspirin, acting as an analgesic agent.

Every subject is sensitive to a drug; the question of importance is "how sensitive?" In any event sensitivity is a property ascribed to the organism; potency is a property ascribed to the drug. Hypersensitivity is a property ascribed to a subject in a particular immunologic state.

Sensitivity may be measured or described quantitatively in terms of the point of intersection of a dose-effect curve with the axis of abscissal values or a line parallel to it; such a point corresponds to the dose just required to produce a given degree of effect (see Threshold"). In analogy to this, the "sensitivity" of a measuring system is defined as the lowest input (smallest dose) required to produce a given degree of output (effect).

 Cf. Supersensitivity, Hypersensitivity, Allergic Response, Potency, Accuracy 

(ANSI) Programs, procedures, rules, and any associated documentation pertaining to the operation of a system. Contrast with hardware.

See: software review

(IEEE) A representation of software created to facilitate analysis, planning, implementation, and decision making. The software design description is used as a medium for communicating software design information, and may be thought of as a blueprint or model of the system.

(IEEE) The process by which user needs are translated into a software product. the process involves translating user needs into software requirements, transforming the software requirements into design, implementing the design in code, testing the code, and sometimes installing and checking out the software for operational activities. Note: these activities may overlap or be performed iteratively.

(NIST) Technical data or information, including computer listings and printouts, in human readable form, that describe or specify the design or details, explain the capabilities, or provide operating instructions for using the software to obtain desired results from a software system.

(IEEE) A deliverable or in- process document produced or acquired during software development or maintenance. Specific examples include but are not limited to:

(1) Project planning documents; i.e., software development plans, and software verification and validation plans.

(2) Software requirements and design specifications.

(3) Test documentation.

(4) Customer-deliverable documentation.

(5) Program source code.

(6) Representation of software solutions implemented in firmware.

(7) Reports; i.e., review, audit, project status.

(8) Data; i.e., defect detection, test.

(IEEE) (1) the probability that software will not cause the failure of a system for a specified time under specified conditions. The probability is a function of the inputs to and use of the system in the software. The inputs to the system determine whether existing faults, if any, are encountered. (2) The ability of a program to perform its required functions accurately and reproducibly under stated conditions for a specified period of time.

(IEEE) An evaluation of software elements to ascertain discrepancies from planned results and to recommend improvement. This evaluation follows a formal process. Synonym: software audit. See: code audit, code inspection, code review, code walkthrough, design review, specification analysis, static analysis.

(1) (IEEE) Computer instructions and data definitions expressed in a form suitable for input to an assembler, compiler or other translator. (2) The human readable version of the list of instructions [program] that cause a computer to perform a task. Contrast with object code.

(IEEE) A document that specifies, in a complete, precise, verifiable manner, the requirements, design, behavior, or other characteristics of a system or component, and often, the procedures for determining whether these provisions have been satisfied. Contrast with requirement.

(NIST) A specification that documents how a system is to be built. It typically includes system or component structure, algorithms, control logic, data structures, data set [file] use information, input/output formats, interface descriptions, etc. Contrast with design standards, requirement.

(NIST) A specification that documents the functional requirements for a system or system component. It describes what the system or component is to do rather than how it is to be built. Often part of a requirements specification. Contrast with requirement.

(IEEE) A document that sets forth the performance characteristics that a system or component must possess. These characteristics typically include speed, accuracy, and memory usage. Often part of a requirements specification. Contrast with requirement.

(IEEE) A document that sets forth the performance characteristics that a system or component must possess. These characteristics typically include speed, accuracy, and memory usage. Often part of a requirements specification. Contrast with requirement.

Written procedures [prescribing and describing the steps to be taken in normal and defined conditions] necessary to assure control of production and processes.

(MCC) Foil, wire or semiconductor devices that convert pressure (stress or strain) into electrical current. Strategically placed in process equipment, they quantify critical forces for analysis. Foil gages feature a robust application range, different nominal resistance and transverse sensitivity control. They are most commonly used for tablet press instrumentation.

(1) (ANSI) People, machines, and methods organized to accomplish a set of specific functions. (2) (DOD) A composite, at any level of complexity, of personnel, procedures, materials, tools, equipment, facilities, and software. The elements of this composite entity are used together in the intended operational or support environment to perform a given task or achieve a specific purpose, support, or mission requirement.

(ISO) A process of defining the hardware and software architecture, components, modules, interfaces, and data for a system to satisfy specified requirements. See: design phase, architectural design, functional design.

(IEEE) A review conducted to evaluate the manner in which the requirements for a system have been allocated to configuration items, the system engineering process that produced the allocation, the engineering planning for the next phase of the effort, manufacturing considerations, and the planning for production engineering.

See: design review

(ISO) The collection of documents that describe the requirements, capabilities, limitations, design, operation, and maintenance of an information processing system.

(1) (ISO) Application- independent software that supports the running of application software. (2) (IEEE) Software designed to facilitate the operation and maintenance of a computer system and its associated programs; e.g., operating systems, assemblers, utilities. Contrast with application software.

(MCC) A module of MCC AIM System that is designed to measure and record critical forces in the tableting process. Real Time software provides quantitative reports and graphics valuable to formulation studies in the lab. AIM-TPM is customized to accommodate any R&D press currently used in the industry today.

(IEEE) An activity in which a system or component is executed under specified conditions, the results are observed or recorded and an evaluation is made of some aspect of the system or component.

(IEEE) (1) The degree to which a system or component facilitates the establishment of test criteria and the performance of tests to determine whether those criteria have been met. (2) The degree to which a requirement is stated in terms that permit establishment of test criteria and performance of tests to determine whether those criteria have been met.

(IEEE) Documentation specifying the details of the test approach for a software feature or combination of software features and identifying the associated tests.

(IEEE) Documentation describing plans for, or results of, the testing of a system or component, Types include test case specification, test incident report, test log, test plan, test procedure, test report.

(IEEE) A chronological record of all relevant details about the execution of a test.

(IEEE) The period of time in the software life cycle in which the components of a software product are evaluated and integrated, and the software product is evaluated to determine whether or not requirements have been satisfied.

(IEEE) Documentation specifying the scope, approach, resources, and schedule of intended testing activities. It identifies test items, the features to be tested, the testing tasks, responsibilities, required, resources, and any risks requiring contingency planning. See: test design, validation protocol.

(NIST) A formal document developed from a test plan that presents detailed instructions for the setup, operation, and evaluation of the results for each defined test.

(IEEE) A document describing the conduct and results of the testing carried out for a system or system component.

(IEEE) (1) The process of operating a system or component under specified conditions, observing or recording the results, and making an evaluation of some aspect of the system or component. (2) The process of analyzing a software item to detect the differences between existing and required conditions, i.e. bugs, and to evaluate the features of the software items.

(IEEE) Testing conducted to determine whether or not a system satisfies its acceptance criteria and to enable the customer to determine whether or not to accept the system.

(Pressman) Acceptance testing performed by the customer in a controlled environment at the developer's site. The software is used by the customer in a setting approximating the target environment with the developer observing and recording errors and usage problems.

(1) (Pressman) Acceptance testing performed by the customer in a live application of the software, at one or more end user sites, in an environment not controlled by the developer. (2) For medical device software such use may require an Investigational Device Exemption [IDE] or Institutional Review Board [IRB] approval.

(IEEE) Testing conducted during the development of a system or component, usually in the development environment by the developer.

(IEEE) Testing conducted in accordance with test plans and procedures that have been reviewed and approved by a customer, user, or designated level of management.

(IEEE) (1) Testing that ignores the internal mechanism or structure of a system or component and focuses on the outputs generated in response to selected inputs and execution conditions. (2) Testing conducted to evaluate the compliance of a system or component with specified functional requirements and corresponding predicted results. Synonym: black-box testing, input/output driven testing.

(IEEE) An orderly progression of testing in which software elements, hardware elements, or both are combined and tested, to evaluate their interactions, until the entire system has been integrated.

(IEEE) Testing conducted to evaluate whether systems or components pass data and control correctly to one another. Contrast with testing, unit; testing, system.

(IEEE) Testing conducted to evaluate a system or component in its operational environment.

(IEEE) Functional testing conducted to evaluate the compliance of a system or component with specified performance requirements.

(IEEE) Formal testing, usually conducted by the developer for the consumer, to demonstrate that the software meets its specified requirements.

See: testing, acceptance; testing, system

(IEEE) The process of testing an integrated hardware and software system to verify that the system meets its specified requirements. Such testing may be conducted in both the development environment and the target environment.

A touch sensitive display screen that uses a clear panel over or on the screen surface. The panel is a matrix of cells, an input device, that transmits pressure information to the software.

(IEEE) (1) A record of the execution of a computer program, showing the sequence of instructions executed, the names and values of variables, or both. Types include execution trace, retrospective trace, subroutine trace, symbolic trace, variable trace. (2) To produce a record as in (1). (3) To establish a relationship between two or more products of the development process; e.g., to establish the relationship between a given requirement and the design element that implements that requirement.

(MCC) The step-by-step transfer process by which the transducer calibration can be related to primary standards.

(IEEE) (1) The degree to which a relationship can be established between two or more products of the development process, especially products having a predecessor-successor or master-subordinate relationship to one another; e.g., the degree to which the requirements and design of a given software component match. See: consistency. (2) The degree to which each element in a software development product establishes its reason for existing; e.g., the degree to which each element in a bubble chart references the requirement that it satisfies.

A device that converts energy from one form to another. A bathroom scale converts force (weight) to a real quantity.

A method of attacking a computer system, typically by providing a useful program which contains code intended to compromise a computer system by secretly providing for unauthorized access, the unauthorized collection of privileged system or user data, the unauthorized reading or altering of files, the performance of unintended and unexpected functions, or the malicious destruction of software and hardware. See: bomb, virus, worm.

(IEEE) (1) A separately testable element specified in the design of a computer software element. (2) A logically separable part of a computer program. Synonym: component, module.

(IEEE) The ease with which a user can learn to operate, prepare inputs for, and interpret outputs of a system or component.

(ANSI) Any person, organization, or functional unit that uses the services of an information processing system.

(ISO) Documentation that describes how to use a functional unit, and that may include description of the rights and responsibilities of the user, the owner, and the supplier of the unit. Synonym: user manual, operator manual.

(IEEE) Computer programs or routines designed to perform some general support function required by other application software, by the operating system, or by the system users. They perform general functions such as formatting electronic media, making copies of files, or deleting files.

(1) Sound. (2) Well grounded on principles of evidence. (3) Able to withstand criticism or objection.

To prove to be valid.

(1) (FDA) Establishing documented evidence which provides a high degree of assurance that a specific process will consistently produce a product meeting its predetermined specifications and quality attributes. Contrast with data validation.

(MCC) Assuring that product requirements are met and documented in accordance with FDA guidelines for the pharmaceutical industry.

(MCC) The degree to which output reflects what it purports to reflect, i.e., input; the degree to which output is a function of known input and it alone. For example, does an essay examination validly measure a student's knowledge of material, or is it invalid, actually measuring his literary skill or the state of the grader's digestion?

(FDA) Establishing documented evidence which provides a high degree of assurance that a specific process will consistently produce a product meeting its predetermined specifications and quality characteristics.

(FDA) A written plan stating how validation will be conducted, including test parameters, product characteristics, production equipment, and decision points on what constitutes acceptable test results.

(NBS) Determination of the correctness of the final program or software produced from a development project with respect to the user needs and requirements. Validation is usually accomplished by verifying each stage of the software development life cycle.

(NIST) Used as an entity to define a procedure of review, analysis, and testing throughout the software life cycle to discover errors, determine functionality, and ensure the production of quality software.

(FDA) A name, label, quantity, or data item whose value may be changed many times during processing. Contrast with constant.

(FDA) A person or an organization that provides software and/or hardware and/or firmware and/or documentation to the user for a fee or in exchange for services. Such a firm could be a medical device manufacturer.

(NBS) In general the demonstration of consistency, completeness, and correctness of the software at each stage and between each stage of the development life cycle. See: validation, software.

(ANSI) (1) To determine whether a transcription of data or other operation has been accomplished accurately. (2) To check the results of data entry; e.g., keypunching. (3) (Webster) To prove to be true by demonstration.

(FDA) An initial release or a complete re-release of a software item or software element.

(FDA) A unique identifier used to identify software items and the related software documentation which are subject to configuration control.

(FDA) A program which secretly alters other programs to include a copy of itself, and executes when the host program is executed. The execution of a virus program compromises a computer system by performing unwanted or unintended functions which may be destructive.

See: bomb, trojan horse, worm

(MCC) A special arrangement of strain gages to ensure signal balancing and temperature sensitivity compensation.

(1) (IEEE) Testing that takes into account the internal mechanism [structure] of a system or component. Types include branch testing, path testing, statement testing. (2) Testing to insure each program statement is made to execute during testing and that each program statement performs its intended function. Contrast with functional testing.

(FDA) Any terminal or personal computer.

(FDA) An independent program which can travel from computer to computer across network connections replicating itself in each computer. They do not change other programs, but compromise a computer system through their impact on system performance.

See: bomb, trojan horse, virus

(MCC) The output signal of a transducer with rated Excitation and with no load applied, usually expressed in percent of Rated Output.

(MCC) The difference in zero balance measured immediately before rated load application (of specified duration) and after removal of the load, and when the output has stabilized.