Reliability of serum S100B measurement following mild traumatic brain injury: a comparison of assay measurements from two laboratories

: Grant L. Iverson, Jussi P. Posti , Juha Öhman , Kaj Blennow , Henrik Zetterberg, Teemu Miikka Luoto

Publisher: TAYLOR & FRANCIS LTD

: 2020

Brain Injury

: BRAIN INJURY

: 34

: 9

: 1237

: 1244

: 8

: 0269-9052

: 1362-301X

DOI: https://doi.org/10.1080/02699052.2020.1800092

Objective There is enormous research and clinical interest in blood-based biomarkers of mild traumatic brain injury (MTBI) sustained in sports, daily life, or military service. We examined the reliability of a commercially available assay for S100B used on the same samples by two different laboratories separated by 2 years in time. Methods and Procedures A cohort of 163 adult patients (head CT-scanned, n = 110) with mild head injury were enrolled from the emergency department (ED). All had Glasgow Coma Scale scores of 14 or 15 in the ED (94.4% = 15). The mean time between injury and venous blood sampling was 2.9 h (SD = 1.4; Range = 0.5-6.0 h). Serum S100B was measured at two independent centers using the same high throughput clinical assay (Elecsys S100B (R); Roche Diagnostics). Results The Spearman correlation between the two assays in the total sample (N = 163) was r = 0.93. A Wilcoxson Signed Ranks test indicated that the median scores for the values differed (Z = 2,082,p< .001, Cohen's d = 0.151, small effect size). The values obtained from the two laboratories were very similar for identifying traumatic intracranial abnormalities (sensitivity = 80.1% versus 85.7%). Conclusions The serum S100B results measured using the same assay in different laboratories yielded highly correlated and clinically similar, but clearly not identical, results.

Emergency Treatment, S100B protein, traumatic brain injuries