1、September 2015 English price group 10No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 11.100.01!%Mpu“2427782www.din.
2、deDIN 58964Quality assurance of POCT results Assessment criteria for comparison measurement and implementation,English translation of DIN 58964:2015-09Sicherstellung der Qualitt von POCT-Ergebnissen Bewertungskriterien fr Vergleichsmessungen bei Implementierung,Englische bersetzung von DIN 58964:201
3、5-09Assurance de la qualit des rsultats POCT Critres dvaluation des mesures comparatives et dimplmentation,Traduction anglaise de DIN 58964:2015-09www.beuth.deDocument comprises 16 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritativ
4、e.09.16 DIN 58964:2015-09 2 A comma is used as the decimal marker. Contents Page Foreword . 3 Introduction 4 1 Scope 5 2 Normative references 5 3 Terms and definitions 5 4 Symbols and abbreviations 6 5 Requirements 7 6 Concordance of measurands . 7 6.1 General 7 6.2 Selection of sample types and sam
5、ple numbers 7 6.3 Data analysis . 8 6.4 Comparison of the methods and acceptance criteria . 8 6.4.1 General 8 6.4.2 Concordance analyses 8 6.4.3 Error grid 9 6.4.4 Acceptance criteria . 10 7 Concordance analysis when implementing POCT . 10 8 Checking the concordance analysis 10 Annex A (informative)
6、 Example of concordance analyses . 11 Bibliography . 15 DIN 58964:2015-09 3 Foreword This document has been prepared by Working Committee NA 063-03-11 AA Patientennahe Sofortdiagnostik (POCT) (“Point-of-Care-Testing (POCT)”) of DIN-Normenausschuss Medizin (DIN Standards Committee Medicine). Attentio
7、n is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN shall not be held responsible for identifying any or all such patent rights. DIN 58964:2015-09 4 Introduction “POCT” are examination procedures that use in vitro diagnostic medical devic
8、es that are used at the bedside or in the immediate vicinity of the patient. Internationally, the term “Point-of-Care-Testing” has become established. A standard, globally accepted definition for POCT does not exist. Important properties of POCT are summarized below. In exceptional cases, in vitro d
9、iagnostic testing is also known as POCT if not all but the main criteria that determine the typical character of such diagnostic procedures are met: a) location of the analytical system outside of a central or satellite laboratory; b) in vitro diagnostic testing in the immediate vicinity of the pati
10、ent; c) examination is carried out mainly of blood, without sample preparations; d) analytics with measuring equipment, intended primarily for single sample measurement; e) ready-to-use reagents for only one analysis (unit-use); f) simple device functions that can be operated by POCT users without d
11、etailed medical-technical skills; g) regular automatic monitoring of the device function; h) rapid availability of the testing results for immediate therapeutic consequences. POCT devices are required to meet the essential requirements of European Directive 98/79/EC on in vitro diagnostic medical de
12、vices (IVD Directive) for the analytical and diagnostic quality and performance, including requirements for metrological traceability of the results. Moreover, the use of POCT diagnostics in Germany is subject to quality requirements which have been made mandatory by Guidelines from the German Medic
13、al Council (RiliBK 2014). Whether an analysis procedure has to be implemented in a central laboratory or as POCT is a complex decision, with the undisputed principle being that better treatment results represent the decisive criterion. The benefits of POCT devices (few preanalytical problems, short
14、analysis times) are offset by methodological and analytical limitations. These include, among others, differing results between POCT devices (e.g. of different manufacturers) and/or compared with results of the central laboratory. POCT procedures are used in daily clinical practice, on an outpatient
15、 basis and in the area of self-testing. Different POCT devices with partly different method principles are now increasingly being used for the same measurand. The prerequisites for the diagnostic suitability of this procedure are appropriate analytical reliability and the equivalence of different me
16、thods (both POCT and non-POCT) for the same measurand. The concordance of the results is to be ensured for routine applications. POCT is used, for example, in the following functional areas: emergency hospitalization; operating room/recovery room; intensive care unit; delivery room/neonatal ward; wa
17、rds with diabetic care; pulmonary function tests; invasive radiology; outpatient facilities such as established doctors practices and dialysis centres; care facilities. DIN 58964:2015-09 5 1 Scope This standard is aimed at manufacturers and users. In the following, procedures for the assessment of c
18、omparison measurements are described that consider the specific situation of simultaneous application of POCT procedures and methods in the central laboratory. This standard specifies measures for the analytical and clinical assessment of a measurand when using different diagnostic methods (both POC
19、T and non-POCT) in medical diagnostic testing. The measures shall ensure that results that are determined in various sample materials are concordant. Samples within the meaning of this standard are native blood or anti-coagulated blood, urine and other body fluids of patients treated in the facility
20、. POCT is used in the context of medical treatment, but also outside of medical science. This standard only applies for POCT within the context of medical science but not for POCT in self-testing. 2 Normative references The following documents, in whole or in part, are normatively referenced in this
21、 document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. DIN EN ISO 15189:2013-03, Medical laboratories Requirements for quality and competence
22、(ISO 15189:2012) DIN EN ISO 17511, In vitro diagnostic medical devices Measurement of quantities in biological samples Metrological traceability of values assigned to calibrators and control materials Richtlinie der Bundesrztekammer zur Qualittssicherung laboratoriumsmedizinischer Untersuchungen (Gu
23、idelines of the German Medical Association on quality assurance in medical laboratory testing) (RiliBK 2014), Deutsches rzteblatt 2014; Jg. 111: pp. A 1583 A 1618 3 Terms and definitions For the purpose of this document, the following terms and definitions apply. 3.1 Kappa coefficient difference bet
24、ween the proportions of agreement actually observed (p0) and expected to occur due to chance (pe), divided by 1 =(0e)(1e)Where 0are proportions of actually observed agreement are proportions of agreement expected to occur due to chance 0are proportions of matches exceeding those occurring due to cha
25、nce Note 1 to entry: The denominator is used for standardization purposes. DIN 58964:2015-09 6 3.2 concordance agreement of measurement results for clinical-chemical analysis of different procedures, whereby the differences of the measured values between the procedures do not exceed limits that are
26、significant for medical diagnostics 3.3 longitudinal assessment of clinical-chemical measurements progress-monitoring assessment of clinical-chemical measurements consideration of temporal consequences of results from the same individual, referred to as time series 3.4 measurand quantity intended to
27、 be measured Note 1 to entry: The specification of a measurand requires knowledge of the kind of quantity, description of the state of the phenomenon, body, or substance carrying the quantity, including any relevant component, and the chemical entities involved. Note 2 to entry: In the second editio
28、n of the VIM and in IEC 60050-300:2001, the measurand is defined as the “particular quantity subject to measurement”. Note 3 to entry: The measurement, including the measuring system and the conditions under which the measurement is carried out, might change the phenomenon, body, or substance such t
29、hat the quantity being measured may differ from the measurand as defined. In this case, adequate correction is necessary. EXAMPLE The glucose concentration in the plasma is determined in analyses using isotope dilution gas chromatography/mass spectrometry from the measurement signals for a mass frag
30、ment of a glucose derivative. For analyses with the hexokinase/glucose-6-phosphate dehydrogenase method, the change in absorbance at a specific wavelength, which results from the enzymatic degradation of the glucose with the formation of NADPH, is detected. SOURCE: International Vocabulary of Metrol
31、ogy (VIM), 2012-08*), Definition 2.3 (2.6); Examples 1 and 2 and Note 4 to entry have not been adopted; a new example has been added. 4 Symbols and abbreviations POCT Point-of-Care-Testing M1 POCT method M1DPOCT method for D-dimer determination M1TPOCT method for troponin determination M2 Reference
32、method or laboratory method M2DReference method for D-dimer determination M2TReference method for troponin determination x Concentration of the substance to be detected xDD-dimer concentration xhConcentration of human chorionic gonadotropin (hCG) xTTroponin concentration *)Translators note. Correspo
33、nds to ISO IEC Guide 99, 2007. DIN 58964:2015-09 7 5 Requirements The minimum requirements for the analytical methods are: a) the CE marking (or another internationally accepted regulatory marketing authorization) of the in vitro diagnostic medical devices used; b) the metrological traceability acco
34、rding to EN ISO 17511; NOTE In some fields (e.g., rapid diagnostics for infectious diseases) this is not applicable. c) definition of medical purpose and use of the reference method; this purpose shall include the purpose intended for the POCT method to be compared; d) a quality assurance system for
35、 the methods of analysis to be compared, which satisfies the regulatory requirements; in Germany this is the Richtlinie der Bundesrztekammer zur Qualittssicherung laboratoriumsmedizinischer Untersuchungen, especially Parts B1 to B3. 6 Concordance of measurands 6.1 General The development of POCT is
36、relatively complex and is only undertaken once a medical indication based on a laboratory method has been established for a measurand (e.g. glucose concentration in plasma or capillary blood). The specification of a measurand in the area of medical laboratory diagnostic testing depends significantly
37、 on the sample matrix and on the surrounding matrix in which the analyte (e.g. glucose) is examined. POCT and conventional medical laboratory methods are usually not identical. Therefore, and because POCT and medical laboratory methods are often used side-by-side, criteria for assessing the equivale
38、nce of POCT for the respective medical laboratory method shall be formulated in order to enable the medical decision. 6.2 Selection of sample types and sample numbers Samples within the meaning of this standard are native blood or anti-coagulated blood, urine and other body fluids of patients treate
39、d in the facility. The samples to be used for the method comparison shall be representative of the facility in terms of patients and indications. Samples in the normal area, grey area and pathological ranges shall be taken and analysed in the context of the local routine. The comparison measurements
40、 shall be carried out by those persons who work with the devices on a daily basis. To achieve a meaningful statistical evaluability of the results, an appropriate number of samples is to be used per value area. When comparing an analytical method implemented by the central laboratory or POCT, an add
41、itional blood sample (mostly capillary) is taken in many cases. NOTE If such a blood sample needs to be taken for the purpose of the method evaluation, where necessary the responsible ethics committee or other institution is to be informed. The respective applicable principles and rules of German me
42、dical products legislation shall be observed (see also 1, 2, 3, 4). The requirements for ethical behaviour according to DIN EN ISO 15189:2014-11, 4.1.1.3, shall be considered. DIN 58964:2015-09 8 6.3 Data analysis The following criteria for the quality of data as a prerequisite for further review ap
43、ply: the quality assurance in accordance with Section 5, d) is satisfied; the relevant concentration range is covered by a sufficient number of measurement pairs. NOTE A first analysis of the variation of the individual measurement pairs without reference to the medical evaluation can be done via a
44、Bland Altman plot 2. The result can support the interpretation of the concordance analysis (see 6.4). 6.4 Comparison of the methods and acceptance criteria 6.4.1 General Two diagnostic methods are medically concordant if the results lead to the same result interpretation and to the same therapeutic
45、consequence. Typical examples are: a) normal/not normal; b) underdosed/correct dosage/overdosed; c) action required? Yes/No. This concordance can only be mapped imperfectly with conventional methods of regression analysis. The assessment of axis intercept and slope is no guarantee that matching resu
46、lts will be found in the decision area. In addition, the measurement uncertainty components in laboratory and POCT methods are different. This concerns, for example, the partial steps of the preanalytics, the properties of the sample material and the expertise of the user. Therefore, concordance ana
47、lyses and error grids are better suited for the assessment of medical equivalence. 6.4.2 Concordance analyses The simplest form of concordance analysis is a four-field table (Table 1). Examples of measurement categories for which a four-field table can be an appropriate representation are results of
48、 pregnancy tests or pathogen detection. The quality of the match can be recorded and expressed using a number, the Kappa coefficient 6. The maximum possible value is 1 (complete match). Table 1 Four-field table M2 negative M2 positive M1 negative Yes No M1 positive No Yes Very often, the medical cla
49、ssification is based on a decision boundary (cut-off). Since both POCT (M1) and the laboratory method (M2) are subject to some inaccuracy, a grey area exists around this cut-off, in which the result is neither clearly negative nor clearly pathological. This situation can be illustrated with the help of a nine-field table (Table 2). An example is the D-dimer concentration for excluding diagnosis of a thromboembolic di
