Establishing the reference change values (RCVs) and validating the delta check auto-verification in a clinical biochemistry laboratory

Aims: Establishing the reference change values (RCVs) and validating the delta check auto-verification in the hospital information system (HIS). Materials and Methods: This study was conducted in the Hospital Laboratory-Biochemistry. Fifty-one parameters were analyzed in three phases. Phase I : Delta check reference change values were established. Phase II : Delta check auto-verification was validated in the hospital information system. Phase III : Calculation of test requiring manual verification, true and false positive rates. Results: Out of all the test results, 1.35% failed the RCV-delta check thus requiring manual verification, and the remaining 98.65% were auto-verified. Only 0.12% test results were true positives indicating laboratory error, and 1.23% were false positives and were correlated clinically. Ten percent simulated data results and 0.37% actual patient results were not identified by the newly introduced HIS. Conclusions: RCV-delta check is a refined form of the delta checks used to analyze acceptable analytical and biological variation in laboratories. Majority of tests passed the RCV-delta check auto-verification, implying that very few test reports require manual verification. True positives can be detected in the laboratory. All HISs should be validated before implementing complete auto-verification.