2.3.1. Saliva Sample Collection
’s mouth
The collection of saliva samples was completed by uniformly trained doctors or nurses in the hospital on the day the subjects were recruited or followed up. All saliva samples were collected between 9 a.m. and 11 a.m. A saliva sample was collected by inserting a cotton swab into the subject’s mouth and letting it rest on the floor of the mouth for 30 s. Immediately after collection, the swab filled with saliva was placed into the tube insert of a salivette collection device (Salivette Cortisol, code blue; 51.1534.500, Sarstedt, Sinnottstown Lane, Drinagh, Wexford, Ireland). Samples were centrifuged by the research nurse/assistant at 1000× 