I am reviewing studies that assessed stress. The most commonly used tool is the perceived stress scale. I am attempting to interpret the data which is reported as a mean score. I haven't found any studies that have cut off scores related to levels/intensity of stress. I have read internet articles where scores are interpreted in terms of intensity e.g. but they don't give the research behind the cut off score, see below
http://podcast.uctv.tv/webdocuments/COHEN-PERCEIVED-STRESS-Scale.pdf
http://christianfamilysolutions.org/sites/default/files/resources/files/Perceived%20Stress%20Scale.pdf
http://iti.vgtu.lt/ceneast/Media/Default/Documents/5th%20Meeting/P1-2_Lina%20Bartkiene_Stress%20scale%20presentation.pdf
I would be grateful if somebody could guide me to research that validates cut off scores for each level/intensity of stress.
Thank
Lloyd