Guidelines on Internal Quality Control

By using the combination of specific method accreditation and generic accreditation it will be possible for laboratories to be accredited for all the analyses of which they are capable and competent to undertake. Method performance validation data demonstrating that the method was fit-for-purpose shall be demonstrated before the test result is released and method performance shall be monitored by on-going quality-control techniques where applicable. It will be necessary for laboratories to be able to demonstrate quality-control procedures to ensure compliance with the EN 45001 Standard,3 an example of which would be compliance with the ISO/AOAC/IUPAC Guidelines on Internal Quality Control in Analytical Chemistry Laboratories.12... 

Guidelines on Internal Quality Control in Analytical Chemistry Laboratories , ed. M. Thompson... 

INTERNATIONAL UNION OF PURE AND APPLIED CHEMISTRY, Guidelines on Internal Quality Control in Analytical Chemistry Laboratories, ed. Thompson M and Wood R, Pure Appl. Chem., 1995 61 649-666. 

ISO, IUPAC and AOAC INTERNATIONAL have co-operated to produce agreed protocols on the Design, Conduct and Interpretation of Collaborative Studies 14 and on the Proficiency Testing of [Chemical] Analytical Laboratories .11 The Working Group that produced these protocols has prepared a further protocol on the internal quality control of data produced in analytical laboratories. The document was finalised in 1994 and published in 1995 as the Harmonised Guidelines For Internal Quality Control In Analytical Chemistry Laboratories .12 The use of the procedures outlined in the Protocol should aid compliance with the accreditation requirements specified above. 

Thus, as for the European Union, the requirements are based on accreditation, proficiency testing, the use of validated methods of analysis and, in addition, the formal requirement to use internal quality control procedures which comply with the Harmonised Guidelines. Although the EU and Codex Alimentarius Commission refer to different sets of accreditation standards, the ISO/IEC Guide 25 1990 and EN 45000 series of standards are similar in intent. It is only through these measures that international trade will be facilitated and the requirements to allow mutual recognition to be fulfilled will be achieved. 

The guidelines stress, however, that internal quality control is not foolproof even when properly executed. Obviously it is subject to errors of both kinds , i.e. runs that are in control will occasionally be rejected and runs that are out of control occasionally accepted. Of more importance, IQC cannot usually identify sporadic gross errors or short-term disturbances in the analytical system that affect the results for individual test materials. Moreover, inferences based on IQC results are applicable only to test materials that fall within the scope of the analytical method validation. Despite these limitations, which professional experience and diligence can alleviate to a degree, internal quality control is the principal recourse available for ensuring that only data of appropriate quality are released from a laboratory. When properly executed it is very successful. 

The method was validated in accordance to the guidelines of the international conference on harmonization (ICH). Data with respect to accuracy, within- and between run precision, recovery, detection and quantitation limits were reported and found to be within the accepted international criteria. Neither endogeneous substances nor the commonly used dmgs were found to interfere with the retention times of the analytes. Standard solutions of the dmg and quality control preparations at high and low level concentrations were demonstrated to be stable at room temperature and/or -20°C for long and short periods of time. 

The quality of a drug substance is controlled by its specification. An internationally harmonized guideline on specifications and tests for chemical substances as active ingredients and in drug products makes reference to chiral compounds. This has recently been finalized and is discussed in Section 13.5.2. 

It is important to issue a common understanding on the topics of method validation, traceability, and uncertainty of measurements. Here, the interrelationships between method validation, traceability, and MU of results will be elucidated. Throughout the landscape of guidelines and standards, the most relevant information is selected, compiled, and summarized. Great importance is attached to the different method performance parameters and their definitions, ways of expression, and approaches for practical assessment. We discuss the role of method validation within QA as well as the topics of standardization, internal and external quality control (IQC and EQC, respectively), and accreditation and the links between these different aspects. 

Quality control procedures are generally established to provide checks on the data that have been collected to evaluate whether in fact the quality assurance procedures were followed and whether the data meet agreed-upon norms. Otherwise, it is difficult for the user to judge the integrity of a data set per se, because there may be few ways to tell that procedures were not followed or values properly recorded. Quality control measures can be linked to the quality assurance procedures. In the example given above for use of field blanks, spikes and duplicate samples, laboratories must provide evidence that their analysis of these samples meets acceptable statistical guidelines for accuracy and precision. Quality control can also simply involve careful analysis of a data set to determine whether it is internally consistent. 

International International Conference on Releases guidelines for quality control, safety testing, www.pharmweb.nt/pwmirror /... 

International Conference on Harmonization Guideline on Data Elements for Transmission of Individual Case Safety Reports. This document s efforts focus on quality control/quality assurance endeavors to ensure accuracy and to promote validation in the handling of case safety reports for both preapproval and postapproval periods. It covers both adverse drug reaction and adverse event reports. 

These activities have enabled WHOPES to plan for the expansion of the Scheme to include the testing and evaluation of a greater variety of pesticides. In recent years, WHOPES has also vigorously promoted the use of WHO specifications for public health pesticides in accordance with the International Code of Conduct on Distribution and Use of Pesticides. Examples of such efforts include the development and wide distribution of guidelines for the purchase of pesticides for public health use, provision of access to WHO specifications for pesticides and their test methods on the Internet, and an increase in the number of WHO collaborating centres for quality control of pesticides (currently three). 

As an analytical approach to residue analysis, immunoassay methods are not well characterized, and no validation protocols have been established. The Association of Official Analytical Chemists, whose primary purpose is validation of analytical methods, established a Task Force on Test Kits and Proprietary Methods (2), which has addressed some of the issues relating to immunoassay methods. The International Union of Pure and Applied Chemistry s Commission on Food Chemistry has established a Working Group on Immunochemical Methods, whose first project is to develop draft guidelines on criteria for evaluation, validation, and quality control for r o-immunoassay methods (10). Similar guidelines for EIAs will also be developed. These documents will assist in development and standardization of requirements for precision for both between-laboratories and within-laboratory andyses, accuracy, and ruggedness, and— for qualitative methods— false positive and false negative rates. 

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