Exploring the evidence base for Tier 3 specialist weight management interventions for children aged 2-18 years in the UK: a rapid systematic review.

Background: The impact of specialist weight management services (Tier 3) for children with severe and complex obesity in the UK is unclear. This review aims to examine the impact of child Tier 3 services in the UK, exploring service characteristics and implications for practice.

Methods: Rapid systematic review of any study examining specialist weight management interventions in any UK setting including children (2-18 years) with a body mass index >99.6th centile or >98th centile with comorbidity.

Results: Twelve studies (five RCTs and seven uncontrolled) were included in a variety of settings. Study quality was moderate or low and mean baseline body mass index z-score ranged from 2.7 to 3.6 units. Study samples were small and children were predominantly older (10-14 years), female and white. Multidisciplinary team composition and eligibility criteria varied; dropout ranged from 5 to 43%. Improvements in zBMI over 1-24 months ranged from -0.13 to -0.41 units.

Conclusions: Specialist weight management interventions for children with severe obesity demonstrated a reduction in zBMI, across a variety of UK settings. Studies were heterogeneous in content and thus conclusions on service design cannot be drawn. There is a paucity of evidence for Tier 3 services for children, and further research is required.