Variation in 1(3S) and 2(2S) rejections incidence in internal quality control program on using 20 reading mean and SD of different periods

Abstract

Objectives: Objective of the study is to measure dispersion of 1(3S) and 2(2S) rejection incidence in six month period using mean and SD derived from 20 readings of different periods of internal quality control program. Material and Method: Data collected from LIS were analyzed in computerized spreadsheet. For various 20 reading slots, mean and SD were calculated. They were used to find 1(3S) and 2(2S) rejection incidences for each set of mean and SD. Result and Discussion: By using 20 reading SD and mean of different period, Incidence of 1(3S) rejection varied from 0-17 percent for ALT, 0-4 percent for ALB, 0-38 percent for GLC, 0-4 percent for TBIL, 0-2 percent for DBIL, 0-10 percent for CR, 0-40 percent for Na, 0-61 percent for K, 0-21 percent for URE, 0-16 percent for TP. Incidence of 2(2S) rejection varied from 0-16 percent for ALT, 0-9 percent for ALB, 0-19 percent for GLC, 0-2 percent for TBIL, 0-2 percent for DBIL, 0-6 percent for CR, 0-17 percent for Na, 0-25 percent for K, 0-11 percent for URE, 0-15 percent for TP. Conclusion: Use of 20 data points for calculation of SD and Mean for new lot of QC sera, as suggested by CLSI C24-A2 results in wide variation in 2(2S) and 1(3S) rejection incidences. New SD and mean should be calculated as soon as larger data set is available.