Associations between sociodemographic, sampling and health factors and various salivary cortisol indicators in a large sample without psychopathology

Sociodemographic variables (sex, age), sampling factors (awakening time, working day, sampling month, sleep duration) and health indicators (smoking, physical activity, cardiovascular disease) were shown to influence different features of salivary cortisol levels. Smoking had the most consistent effect on all cortisol variables. These factors should be considered in psychoneuroendocrinology research.