CMAJ OPEN

According to the World Health Organization, school-aged children and youth (aged 5–19 years) whose weight is greater than the 85th centile are over-weight, and those whose weight is above the 97th centile are obese; younger children (aged 2–5 years) must be over the 97th centile to be considered overweight and more than the 99.9th centile to be considered obese.1 A recent Canadian Health Measures Survey (2009–2011) reported obesity prevalence among 5- to 17-year-olds at 11.7%, with an addi-tional 19.8 % classified as overweight.2 In the United States, obesity prevalence among 2- to 19-year-olds (2009–2010) was reported at 16.9%, with another 14.9 % considered over-weight.3 Obesity that begins in childhood usually persists into adulthood4 and is associated with adverse outcomes including metabolic, cardiovascular, musculoskeletal, neurologic, gas-trointestinal, respiratory and psychosocial disturbances.5–10 The predicted increase in childhood obesity has intensified the urgency of improving treatment approaches for the pediatric population. Treatment of childhood and adolescent obesity is an active area of research, and a number of systematic reviews have been published recently.11–17 Comprehensive behav-ioural interventions including changes in diet, physical activ-ity and lifestyles involving individual patients or families are Treatment of overweight and obesity in children and youth: a systematic review and meta-analysi