Epidemiology of chronic pain in children and adolescents: a protocol for a systematic review update.

Introduction Chronic pain, defined as persistent or recurring pain or pain lasting longer than 3 months, is a common childhood problem and can profoundly impact children’s physical, psychological and social functioning. The last comprehensive systematic review estimating the prevalence of chronic pain in children and adolescents was published in 2011. Since then, the literature on paediatric chronic pain has grown substantially. This manuscript outlines a protocol for an updated systematic review to provide updated estimates of the prevalence of various forms of chronic pain in children and adolescence. The review will also examine the relationship between sociodemographic and psychosocial factors related to chronic pain prevalence. Methods and analysis This review will follow Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We will search EMBASE, PubMed, CINAHL and PsycINFO for observational studies published in English between 2009 and 2020 reporting population-based estimates of chronic non-disease-related pain prevalence in children or adolescents (age ≤19 years). Two independent reviewers will screen the titles and abstracts retrieved from the search based on predefined eligibility criteria. The full texts of relevant studies will then be assessed by two reviewers. Studies meeting inclusion criteria will be categorised according to the type of pain investigated: headache only, abdominal pain only, back pain only, musculoskeletal pain, combined pain, general pain and other pain. Data will be extracted using customised forms and studies will be assessed for risk of bias using a 10-item tool developed by Hoy et al (2012). A narrative synthesis will summarise the prevalence estimates of paediatric chronic pain and associated sociodemographic and psychosocial correlates. Meta-analyses and meta-regressions will be performed if the data permit. Ethics and dissemination Ethical approval is not required. Findings will be disseminated through publication in an academic journal, presentations at conferences and in various media. PROSPERO registration number CRD42020198690.