“…The questionnaire (which is presented in Supplementary file 1, available online) comprised two parts: 1) eight questions, adopted from other questionnaires, 27,28 that include details about melatonin dosages, usage patterns (time and frequency), duration of treatment, reason for stopping or continuing treatment, side effects, and source of the medicine; and 2) eight questions that were designed to assess the child's sleep and general daily functioning and behavior, on a scale of 1 to 5 (1 -major negative effect; 2 -minor negative effect; 3 -no effect; 4 -minor positive effect; and 5 -major positive effect), as described previously. [27][28][29] Sociodemographic, behavioral, and clinical data about participating children were obtained from the ANCAN database. Clinical variables included the Autism Diagnostic Observation Schedule™, Second Edition (ADOS®-2) 30 comparison score, the DSM-5 ASD severity levels, the preschool language scale, fourth edition (PLS4) total score, 31 a cognitive score based on either the Bayley Scales of Infant and Toddler Development-third edition (Bayley-III) 32 or the Wechsler Preschool and Primary Scale of Intelligence-version three (WPPSI-III), 33 The General Adaptive Composite (GAC) score of the Adaptive Behavior Assessment System-II (ABAS-II) 34 , and data about the child's sleep quality based on the Children's Sleep Habits Questionnaire (CSHQ).…”