Reference intervals data mining: no longer a probability paper method.

OBJECTIVES: To describe the application of a data-mining statistical algorithm for calculation of clinical laboratory tests reference intervals. METHODS: Reference intervals for eight different analytes and different age and sex groups (a total of 11 separate reference intervals) for tests that are unlikely to be ordered during routine screening of disease-free populations were calculated using the modified algorithm for data mining of test results stored in the laboratory database and compared with published peer-reviewed studies that used direct sampling. The selection of analytes was based on the predefined criteria that include comparability of analytical methods with a statistically significant number of observations. RESULTS: Of the 11 calculated reference intervals, having upper and lower limits for each, 21 of 22 reference interval limits were not statistically different from the reference studies. CONCLUSIONS: The presented statistical algorithm is shown to be an accurate and practical tool for reference interval calculations.