Selcuk Matyar1, Ozlem Goruroglu Ozturk2, Esin Ziyanoglu Karacor2, Sedefgul Yuzbasioglu Ariyurek3, Gulhan Sahin2, Filiz Kibar4, Akgun Yaman4, Tamer Inal2. 1. Central Laboratory, Medical Faculty, Balcali Hospital, Cukurova University, Adana, Turkey. selcukmatyar@yahoo.com. 2. Department of Clinical Biochemistry, Medical Faculty, Cukurova University, Adana, Turkey. 3. Central Laboratory, Medical Faculty, Balcali Hospital, Cukurova University, Adana, Turkey. 4. Department of Clinical Microbiology, Medical Faculty, Cukurova University, Adana, Turkey.
Abstract
BACKGROUND: Neuron-specific enolase (NSE) is a recognized biomarker for the assessment of cerebral injury in neurological disorders. This study aims to report a definitive assessment of the biological variation (BV) components of this biomarker, including within-subject BV (CVI), between-subject BV (CVG), index of individuality (II), and reference change value (RCV), in a cohort of Turkish participants using an experimental protocol. METHODS: Six blood specimens were collected from each of the 13 apparently healthy volunteers (seven women, six men; ranging in age from 23 to 36) on the same day, every 2 weeks for 2 months. Serum specimens were stored at -20°C until analysis. Neuron-specific enolase levels were evaluated in serum samples using an electrochemiluminescence (ECLIA) immunoassay kit with a Roche Cobas e 411 auto-analyser. ANOVA test was used to calculate the variations. RESULTS: The CVI and CVG for NSE were 21.5% and 28.8%, respectively. Analytical variation (CVA) was calculated as 10.2%. Additionally, II and RCV were calculated as 0.74 and 66% (95% confident interval, CI), respectively. CONCLUSION: As the performance index (PI) was found to be less than 2 (PI = 0.95), it is concluded that the NSE measurements have a desirable performance for analytical imprecision. Since the II was found to be less than 1 (II: 0.74), the reference values will be of little use. Thus, RCV would provide better information for deciding whether a significant change has occurred.
BACKGROUND:Neuron-specific enolase (NSE) is a recognized biomarker for the assessment of cerebral injury in neurological disorders. This study aims to report a definitive assessment of the biological variation (BV) components of this biomarker, including within-subject BV (CVI), between-subject BV (CVG), index of individuality (II), and reference change value (RCV), in a cohort of Turkish participants using an experimental protocol. METHODS: Six blood specimens were collected from each of the 13 apparently healthy volunteers (seven women, six men; ranging in age from 23 to 36) on the same day, every 2 weeks for 2 months. Serum specimens were stored at -20°C until analysis. Neuron-specific enolase levels were evaluated in serum samples using an electrochemiluminescence (ECLIA) immunoassay kit with a Roche Cobas e 411 auto-analyser. ANOVA test was used to calculate the variations. RESULTS: The CVI and CVG for NSE were 21.5% and 28.8%, respectively. Analytical variation (CVA) was calculated as 10.2%. Additionally, II and RCV were calculated as 0.74 and 66% (95% confident interval, CI), respectively. CONCLUSION: As the performance index (PI) was found to be less than 2 (PI = 0.95), it is concluded that the NSE measurements have a desirable performance for analytical imprecision. Since the II was found to be less than 1 (II: 0.74), the reference values will be of little use. Thus, RCV would provide better information for deciding whether a significant change has occurred.
Authors: William A Bartlett; Federica Braga; Anna Carobene; Abdurrahman Coşkun; Richard Prusa; Pilar Fernandez-Calle; Thomas Røraas; Neils Jonker; Sverre Sandberg Journal: Clin Chem Lab Med Date: 2015-05 Impact factor: 3.694
Authors: Frank Martin Schmidt; Roland Mergl; Barbara Stach; Ina Jahn; Hermann-Josef Gertz; Peter Schönknecht Journal: Neurosci Lett Date: 2014-04-16 Impact factor: 3.046