Definitions
Article 2
For the purposes of this Regulation, the following definitions apply: (1) ‘true positive’ means a specimen known to be positive for the target marker and correctly classified by the device; (2) ‘false negative’ means a specimen known to be positive for the target marker and misclassified by the device; (3) ‘false positive’ means a specimen known to be negative for the target marker and misclassified by the device; (4) ‘the limit of detection’ (‘LOD’) means the smallest amount of the target marker that can be detected; (5) ‘nucleic acid amplification techniques’ (‘NAT’) means methods of detection and/or quantification of nucleic acids by either amplification of a target sequence, by amplification of a signal or by hybridisation; (6) ‘NAT system’ means the combination of devices used for extraction, amplification and detection of nucleic acids; (7) ‘rapid test’ means a qualitative or semi-quantitative in vitro diagnostic medical device, used singly or in a small series, which involves non-automated procedures (except the reading of results) and has been designed to give a fast result; (8) ‘robustness’ means the capacity of an analytical procedure to remain unaffected by small but deliberate variations in method parameters and provides an indication of its reliability during normal usage; (9) ‘cross-reactivity’ means the ability of non-target analytes or markers to cause false positive results in an assay because of similarity, e.g. the ability of non-specific antibodies binding to a test antigen of an antibody assay, or the ability of non-target nucleic acids to be reactive in a NAT assay; (10) ‘interference’ means the ability of unrelated substances to affect the results in an assay; (11) ‘whole system failure rate’ means the frequency of failures when the entire process is performed as prescribed by the manufacturer; (12) ‘first-line assay’ means a device used to detect a marker or analyte, and the use of which may be followed by the use of a confirmatory assay; devices intended solely to be used to monitor a previously determined marker or analyte are not considered first-line assays; (13) ‘confirmatory assay’ means a device used for the confirmation of a reactive result from a first line assay; (14) ‘supplemental assay’ means a device that is used to provide further information for the interpretation of the test result of another assay; (15) ‘virus typing device’ means a device used for typing with already known positive samples, not used for primary diagnosis of infection or for screening; (16) ‘95 % positive cut-off value’ means the analyte concentration where 95 % of test runs give positive results following serial dilutions of an international reference material, where available, e.g. a World Health Organisation (WHO) International Standard or reference material calibrated against the WHO International Standard.