Clinical chemistry reference intervals in clinically validated healthy individuals: A large single-center study.

BACKGROUND: Accurate reference intervals (RIs) for laboratory test results are essential in clinical practice. To enhance clinical decision-making, refined RIs are needed. Therefore a single-center study was performed with extensively evaluated healthy participants, measuring a large set of biochemical markers. METHODS: In this descriptive, quantitative, a priori direct sampling, single-center study, a total of 18,701 determinations were collected from 8380 healthy adults aged 18 years and older. Age- and sex-specific RIs were established for 36 biochemical assays. RESULTS: Serum concentrations of several biochemical assays remained relatively constant across the adult age range and were similar between sexes (e.g., total calcium, chloride and sodium). Other biochemical assays (e.g., alanine-amino transferase, triglycerides) showed differences, indicating the influence of factors such as age and sex on the observed results. CONCLUSIONS: For the first time in Europe, we established age- and sex-specific RIs for 36 biochemical assays using data from extensively clinically validated healthy participants.