Short term Biological Variation of Differential Count in Healthy Subjects in a South Asian Population

Abstract

ABSTRACTIntroductionEstimates of Within-Subject and between subject biological variation in South Asia are sorely lacking. Therefore, we attempted to estimate the short-term estimates of the same for Differential Counts (DC).MethodsThe study was conducted on twenty eight healthy volunteers (15 males and 13 females). After morning collection of blood in K3-EDTA vials analysis was conducted in triplicate on the Sysmex XN-1000 analyzer for six consecutive days. The Within subject, between subject and analytical coefficient of variation of the DC was calculated from the results by nested repeated measures ANOVA after outlier exclusion. The Reference change values (RCV) were also calculated.ResultsThe within-subject variation for Eosinophil Count in our group from South Asia was greater than the published European and American studies. The between-subject variation in monocytes and basophils were also increased. Males and females showed similar biological variation for DC. The Within-subject variation of other parameters (Neutrophils, Lymphocytes, Monocytes and Basophils) were similar or showed only mild differences to the published studies.ConclusionThe markedly different within-subject variation for Eosinophil counts suggest that the RCV for DC in South Asians need to be different from the published data in order to have clinical relevance. The Within-subject variation values of the other parameters seem transportable from the published European and American studies, but small differences found mean that further regional estimates need to be found for robust evidence of the same.