“…Gaultney et al study, using SLEEP-50 questionnaire that surveyed 1845 students enrolled in Introductory Psychology labs at a large state university in the United States, showed that insomnia was one of the most reported disorders (12%) [ 16 ]. Piro et al study, using the same questionnaire, conducted on a smaller cohort, 316 students from medical colleges (medicine, nursing, dentistry, pharmacy, anesthesia, and medical laboratory sciences) at the public University of Duhok-Iraq, found that RLS was the most prevalent type of sleep disorder, affecting 30.7% of students, followed by insomnia (25.0%), CRD (19.6%), affective disorder (14.5%), and sleep apnea (13.6%) [ 28 ]. This variation in the prevalence rate of different sleep disorders could be attributed to the different studied cohorts, and different methods and designs used in the studies.…”