Commutability of Lombardy Region EQA Control Materials for Enzymes, Calcium, and Creatinine

This dataset contains raw, replicate-level measurements generated in a multicenter study assessing the commutability of External Quality Assessment (EQA) control materials across routine clinical chemistry platforms. No post-processing, outlier removal, bias calculations, uncertainty propagation, or commutability classifications are included here; all values are as reported by the participating instruments in the single analytical run per site. Study design (for data context) Setting: Ten routine clinical laboratories participating in the Lombardy Regional EQA program. Analytes (measurands): ALP, ALT, AST, CK, LDH, CHE, creatinine, calcium. Specimens: Three lyophilized control materials (CM-1/CM-2/CM-3) and fifteen human serum pools. Each site performed one analytical run. CMs were measured in six replicates; pools in three replicates. Routine calibration and IQC preceded each run