title: Service evaluation of weight outcomes as a function of initial BMI in 34,271 adults referred to a primary care/commercial weight management partnership scheme.
abstract: BACKGROUND
  It is not clear if behaviour change programmes are more or less effective for weight management in people with high BMIs than for those who are moderately overweight. An earlier service evaluation reported on the rate and extent of weight loss in a primary care/commercial weight management organisation partnership scheme, in 34,271 patients were referred by their health care professionals to a UK commercial weight management organisation, Slimming World for 12 weekly sessions. This project updated that service evaluation by examining weight loss outcomes as a function of initial BMI in the same 34,271 patients.
  
  
  RESULTS
  Patients referred to the scheme (n = 34,271) were categorised by BMI groups <30 kg/m(2), 30-34.9 kg/m(2), 35-39.9 kg/m(2) and to ≥ 40 kg/m(2). Mean weight losses after 12 weekly sessions were 2.9, 3.6, 4.1, and 4.8 kg for each BMI category respectively. Regression analysis showed that after adjusting for age and gender, relative to the <30 kg/m(2) group, absolute weight losses were 0.8, 1.4 and 2.4 kg more for the 30-34.9 kg/m(2), 35-39.9 kg/m(2) and to ≥ 40 kg/m(2) groups, respectively (all p<0.001). Percent weight loss was similar in each BMI category: 3.7%, 4.0%, 4.0% and 3.9%, respectively (p<0.001).
  
  
  CONCLUSIONS
  This service evaluation demonstrates that 12 week referral to a commercial organisation is as effective for people with high BMIs as for those who are moderately overweight.
authors.affiliation: Nutrition and Research Department, Slimming World, Clover Nook Road, Somercotes, Alfreton, Derbyshire DE55 4RF, UK. james.stubbs@slimming-world.com
authors.forename: Richard James
authors.initials: RJ
authors.lastname: Stubbs
authors.forename: David Johnathan
authors.initials: DJ
authors.lastname: Brogelli
authors.forename: Jenny
authors.initials: J
authors.lastname: Barber
authors.forename: Carolyn
authors.initials: C
authors.lastname: Pallister
authors.forename: Stephen
authors.initials: S
authors.lastname: Whybrow
authors.forename: Amanda
authors.initials: A
authors.lastname: Avery
authors.forename: Jacquie
authors.initials: J
authors.lastname: Lavin
mesh_terms: D000328:Adult; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D015438:Health Behavior; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000628:therapy; D017063:Outcome Assessment, Health Care; D050177:Overweight / Q000628:therapy*; D011320:Primary Health Care / Q000379:methods; D012044:Regression Analysis; D016896:Treatment Outcome; D006113:United Kingdom; D015431:Weight Loss; D061217:Weight Reduction Programs / Q000379:methods*