CONCLUSIONS AND RELEVANCE: In this cross-sectional study of 684 propensity score-matched children, outpatient melatonin use was associated with a small reduction in REM sleep percentage and was not associated with differences in total sleep time, non-REM sleep stages, respiratory parameters, arousal architecture, or periodic limb movements. The REM association was attenuated when psychiatric diagnoses were added to the propensity model. Residual confounding cannot be excluded, and prospective…
