Verifying Performance Characteristics of Quantitative Analytical Systems: Calibration Verification, Linearity, and Analytical Measurement Range

Abstract

Context.—Both the regulations in the Clinical Laboratory Improvement Amendments of 1988 (CLIA) and the checklists of the College of American Pathologists (CAP) Laboratory Accreditation Program require clinical laboratories to verify performance characteristics of quantitative test systems. Laboratories must verify performance claims when introducing an unmodified, US Food and Drug Administration–cleared or approved test system, and they must comply with requirements for periodic calibration and calibration verification for existing test systems. They must also periodically verify the analytical measurement range of many quantitative test systems. Objective.—To provide definitions for many of the terms used in these regulations, to describe a set of basic analyses that laboratories may adapt to demonstrate compliance with both CLIA and the CAP Laboratory Accreditation Program checklists for performing calibration verification and for verifying the analytical measurement range of test systems, to review some of the recommended procedures for establishing performance goals, and to provide data illustrating the performance goals used in some of the CAP's calibration verification and linearity surveys. Data Sources.—The CAP's calibration verification and linearity survey programs, the CLIA regulations, the Laboratory Accreditation Program requirements, and published literature were used to meet these objectives. Conclusions.—Calibration verification and linearity and analytical measurement range verification should be performed using suitable materials with assessment of results using well-defined evaluation protocols. We describe the CAP's calibration verification and linearity programs that may be used for these purposes.

How closely do blood gas electrolytes and haemoglobin agree with serum values in adult emergency department patients: An observational study

“…To determine what proportion of analyses for the parameters above using the blood gas analyser fall outside pre-defined clinically acceptable limits of agreement of sodium concentration AE5 mmol/L, potassium AE0.5 mmol/L and haemoglobin concentration AE10 g/dL and US Clinical Laboratory Improvement Amendment (USCLIA) standards. 1 USCLIA defines acceptable agreement for sodium concentration as AE4 mmol/L, potassium concentration as AE0.5 mmol/L and haemoglobin as AE7%.…”

“…Proportion agreement outside defined clinically acceptable limits of agreement and US CLIA standards1 …”

Cistatina C sérica em cães criticamente enfermos em UTI

“…Nesse estudo utilizou-se o ensaio imunoturbidimétrico humano, devidamente calibrado com a cistatina C canina purificada (Cystatin C Canine E. coli; RD472009100; 0,1mg) com a finalidade de se certificar a acurácia desta técnica (Oliveira & Mendes 2010, Killeen et al 2014 De acordo com a literatura cães hígidos podem apresentar valores de referência entre 0,18-1,60mg∕ L de cistatina C pelo método imunoturbidimétrico (Jensen et al 2001, Almy et al 2002, Braun et al 2002, Pagitz et al 2007, Wehner et al 2008, Monti et al 2012 ser justificados pela utilização de diferentes kits entre os estudos. A concentração de cistatina C em cães hígidos variou de 0,63 a 1,19mg ∕L (média de 0,93 e desvio padrão de ±0,18).…”

Evolution of Quality Assurance for Clinical Immunohistochemistry in the Era of Precision Medicine – Part 2: Immunohistochemistry Test Performance Characteristics

“…Analytical measurement range is the same as "reportable range" in The Clinical Laboratory Improvement Amendments terminology. 51 When applied to IHC testing, which is a descriptive qualitative technique, the reportable range is usually considered to be the clinically relevant range of results that can be described (or measured by image analysis) for a given IHC target that can be detected in specimens known to express the antigen, with the provision that the specimens had undergone ideal tissue processing (eg, ischemic time <1 h, overnight fixation in formalin, and embedding in paraffin). For example, a given range may extend from rare cells positive, to all cells positive, etc.…”