Establishment of reference intervals for the salivary cortisol circadian cycle, by electrochemiluminescence (ECLIA), in healthy adults.

•Salivary cortisol analyzed with ECLIA remains a sensitive and accessible method to evaluate the cortisol cycle on an outpatient basis.•Reference intervals for salivary cortisol are not comparable across first and second-generation Roche Cobas CortisolR assays.•The second-generation assay has a better correlation with LC-MSMS and a better analytical performance (accuracy and precision)®.