Biomarkers Determination of the Nurse in Various Work Environments.

W e read with respect the manuscript by Arnetz et al investigating the potential association between work environment, serum dehydroepiandrosteronesulphate (DHEA-S) and interleukin-6 (IL6), and patient care outcomes. Their study demonstrated the DHEA-S and/or IL-6 as biomarkers of nurse stress and patient outcome. However, we have some comments on the biomarker determination. Firstly, some descriptions that make confusion should be clarified. In Section ‘‘study procedure,’’ blood samples were frozen and stored at –80 8C after collection, we guess the samples kept for further analysis should be serum rather than blood. In Tables 2 and 3, the results of DHEA-S and IL-6 were listed without unit. In Section