The study objective is to characterize how sleep deficiency influences youth's ability to engage with, implement, and benefit from pain self-management intervention. The investigators will recruit a cohort of 80 youth, ages 12 to 17 years, with chronic musculoskeletal, head, or abdominal pain into a single arm trial conducted at one site. Assessments will occur at baseline, immediately after intervention, and repeated at 3 months post-intervention. Mediators will be assessed at mid-treatment (4 weeks). All youth will receive an 8-week internet-delivered pain self-management intervention (WebMAP). Following the recommended Common Data Elements for self-management three self-management processes are measured including patient activation, pain self-efficacy, and self-management skills, and patient-reported outcomes of health (global health, fatigue) and pain (pain symptoms, pain-related disability). Positive and negative affect and executive function are assessed as potential mediators. Sleep deficiency is comprehensively assessed with subjective measures, daily sleep logs, and ambulatory actigraphy monitoring to measure disrupted sleep, amount of sleep, sleep quality, and insomnia symptoms.
