caa a22 4500 605465975 CHVBK 20210128100305.0 cr unu---uuuuu 210128e20151001xx s 000 0 eng 10.1007/s00769-015-1174-8 doi (NATIONALLICENCE)springer-10.1007/s00769-015-1174-8 Qualitative PT data analysis with easy-to-interpret scores [Elektronische Daten] [Steffen Uhlig, Christian Bläul, Kirstin Frost, Susann Sgorzaly, Bertrand Colson, Kirsten Simon] Numerical values called L-scores, with properties similar to those of z-scores, can be calculated for proficiency tests involving qualitative test methods. These scores do not require the use of replicates and are defined in such a way as to reflect both the Level of Competence of the Laboratory (LCL) and the Level of Difficulty of the Task (LDT). On the basis of the "logit” statistical model, the parameters corresponding to the LCL and the LDT values are determined via maximum likelihood estimation. With p denoting the corrected binary response, the model can be interpreted as $$\ln \left( {p/\left( {1 - p} \right)} \right) = LCL - LDT.$$ ln p / 1 - p = L C L - L D T . The estimated parameters are then the quantities used to compute the L-scores for the participating laboratories. In the case of the laboratory-specific L-scores across tasks, the score for a particular laboratory can be computed as the deviation of the individual LCL from the average LCL relative to the standard error. The interpretation of the L-scores is slightly different from that of z-scores If |L|≤2, the competence of the participant is not significantly different from the average competence. If L>2, the competence is significantly higher, while if L<−2, the competence is significantly lower. Springer-Verlag Berlin Heidelberg, 2015 Qualitative test method nationallicence Proficiency test (PT) nationallicence Binary data nationallicence Rate of detection ( ROD ) nationallicence Probability of detection (POD) nationallicence z -score nationallicence L -score nationallicence Logit model nationallicence Uhlig Steffen QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut Bläul Christian QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut Frost Kirstin QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut Sgorzaly Susann QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut Colson Bertrand QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut Simon Kirsten QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut Accreditation and Quality Assurance Springer Berlin Heidelberg 20/5(2015-10-01), 347-353 0949-1775 20:5<347 2015 20 769 https://doi.org/10.1007/s00769-015-1174-8 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00769-015-1174-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Uhlig Steffen QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut NATIONALLICENCE 700 1- Bläul Christian QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut NATIONALLICENCE 700 1- Frost Kirstin QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut NATIONALLICENCE 700 1- Sgorzaly Susann QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut NATIONALLICENCE 700 1- Colson Bertrand QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut NATIONALLICENCE 700 1- Simon Kirsten QuoData GmbH, Prellerstr. 14, 01309, Dresden, Germany aut NATIONALLICENCE 773 0- Accreditation and Quality Assurance Springer Berlin Heidelberg 20/5(2015-10-01), 347-353 0949-1775 20:5<347 2015 20 769