Calculation of indirect reference intervals of plasma lipase activity of adults from existing laboratory data based on the Reference Limit Estimator integrated in the OPUS::L information system

Abstract

Objectives: Most laboratories have difficulties to determine their own reference intervals for the diagnostic evaluation of patient results by direct methods. Therefore, data is often just taken from the literature or package inserts of the analytical tests. Methods: The section on Reference Limits of the German Society for Clinical Chemistry and Laboratory Medicine (DGKL) firstuploaded the Reference Limit Estimator (RLE) as an R-program with MS Excel-interface on the DGKL home page and now this tool is implemented in the commercial Laboratory Information System OPUS::L (OSM AG Essen, Germany). We used this OPUS::L "Population specific Reference Limits"tool online with our laboratory database. First calculations were done using the example of lipase. Results: The manufacturer's original reference interval for lipase 12-53 U/L (adults) was changed to age dependent upper reference limits of <41 U/L (<20 years), <60 U/L (20- 80 years) and <70 U/L (>80 years). Conclusions: By means of the OPUS::L "Population specific Reference Limits"tool we were able to establish our laborarotry specific reference interval for plasma lipase activity. The new reference limits helped to solve an old problem of implausible low elevated lipase values.