Laboratories proficiency testing

International Organization for Standardization (ISO) Guide 43 (1984), Development and Operation of Laboratory Proficiency Testing, ISO, Geneva. 

Increasingly a price of accreditation is mandatory participation in proficiency testing schemes. If the scheme test materials really do match the routine analyses performed by the laboratory, proficiency testing gives an excellent assurance to both the laboratory and the client as to the quality of the laboratory s results. If the scheme has assigned quantity values for the test materials sent out, the cohort as a whole can be judged, and biases at the sector level discovered. 

At the February meeting of the American Academy of Forensic Sciences in Dallas, Texas, the Criminalistics Section supported a resolution that the Forensic Sciences Foundation develop a concept paper for a national system of crime laboratory proficiency testing This, subsequently, resulted in a grant award to the Foundation for an eighteen-month study which will test the feasibility of regular proficiency testing in the nation s forensic laboratories. 

The purpose of this project is to conduct a nationwide criminalistics laboratory proficiency testing program. The objectives of the project are ... 

OPCW S/10/97, Evaluation of Results, Second Official Inter-Laboratory Proficiency Test, Version 2, 26 August 1997. 

The development of CE analytical methods for CW-related compounds has been directed primarily toward the analysis of these compounds in environmental matrices such as soil and water. These methods have been used in the analysis of samples distributed as part of the interlaboratory comparisons exercises, the so-called round-robin exercises coordinated by Finland, and more recently, the OPCW Laboratory Proficiency Testing. 

The selection of an analytical technique and the development of procedures and operating conditions are only one part of the process for achieving reliable measurements. Among the first steps of the validation figure the assessment of the method precision this parameter must be assessed between analysts and days. Appropriate precision, although necessary for reliable work, is not sufficient to guarantee accurate results Evaluation of sample matrix effect, development, and analysis of spiked samples, analysis of Certified Reference Materials (CRM) of similar composition for which the Pb concentration has been established by other laboratories and comparison of results between laboratories (proficiency testing) are equally important [13]. 

The terms inter-laboratory quality control, laboratory proficiency testing, or external surveillance surveys are commonly given to tiie evaluation of the interlaboratory v iation tiiat is expected when the stime delay that dsts between tiie actual laboratory analysis of the sexternal quality assessment is more propriate. 

E626 Hill, S. A., Heathcote, J.C. and McQueen, M.J. (1990). The significance of matrix effects on the measurement of lactate dehydrogenase activity using Kodak dry slide technology in the Ontario Laboratory Proficiency Testing Program. Clin. Biochem. 23, 179-181. 

Nowadays it is generally accepted that laboratory proficiency testing schemes are an important quality assurance tool in environmental monitoring programmes. Apart from using validated analytical methods and internal laboratory quality control procedures, the regular participation of laboratories in interlaboratory comparisons is required to ensure the accuracy and comparability of data. 

The data were assessed by the ISO 5725-2 protocol [3] implemented in the software package Prolab98 (Dr Uhlig, Quo Data, Dresden, Germany), which is routinely used by the German Federal Environmental Agency for evaluation of laboratory proficiency tests. Outliers were rejected by use of Grubbs test (P=l%) and Cochran s test (P=l%). 

The aim of this trial was to validate MARA by evaluating the performance of the assay at different laboratories worldwide. The method of implementation of the testing could have been considered in the same perspective as a collaborative trial used to validate a standard method. The trial was viewed with potential to form the basis of laboratory proficiency testing defined by ISO as determination of laboratory testing performance by means of inter-laboratory comparisons (Horowitz, 1988). 

Thier H-P, Stijve T. and Specht W. (1989). Fres. Z. Anal. Chem. 334, 546-49. Development and Operation of Laboratory Proficiency Testing. (ISO/lEC Guide 43), International Organization for Standardisation 1984, Geneva. 

Analytic issues Qualifications of staff intra- and inter-laboratory proficiency testing of procedures Pathologist/technologist... 

Precision within a laboratory can be tightly controlled by the operation of internal quality control schemes. This can be achieved by undertaking replicated analysis of samples and/or possibly by analysing replicate samples. The analysis of certified reference materials offers a means whereby bias can be estimated. Another means of estimating a laboratory s performance is via participation in inter-laboratory proficiency-testing schemes. Originally, external quality control or inter-laboratory proficiency-testing schemes had been made available to assist laboratories to identify those areas where remedial action was considered necessary, in order to improve the quality of data... 

In each case a referee laboratory is responsible for providing the sample and organizing its distribution and the collation and analysis of the results. For the majority of studies the purpose of the study is to test the laboratory (proficiency testing), the test material (material certification), or the method (method validation study). The purpose determines some of the study parameters. For example, a method validation study requires all the laboratories to use the same method, but for other studies the method may not be prescribed. For materials certification the laboratories are chosen for their demonstrated proficiency in analysis of the material. It would not be appropriate if there was any dubiety concerning the assigned quantity value because of a suspect result. 

One of the criteria for laboratories seeking designation for the analysis of authentic samples is that those laboratories should regularly partieipate and perform suecessfully in inter-laboratory proficiency tests (PC-VI/B/WP.4). Criteria for aeeeptable performance of laboratories in a single proficiency test have been estabhshed (PC-XI/B/WP.6, Annex 1) and adopted by the Commission. 

Samples from international laboratory proficiency test exercises were also analysed, these included five soils from the Mixed Analyte Performance Evaluation Programme (MAPEP), USA Department of Energy, Idaho Falls, Idaho, (MaS21, 23, 24, 25 and 26) and one soil from the Institutde Radioprotection et de Sflrete Nucleaire (IRSN), Le Visenet, Cedex, France, (113SL300). 

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