Which weight-loss programmes are as effective as Weight Watchers(R)?: non-inferiority analysis

Br J Gen Pract. 2014 Mar;64(620):e128-36. doi: 10.3399/bjgp14X677491.


Background: Three randomised controlled trials have provided strong evidence that Weight Watchers(®) is an effective weight-loss programme but there is insufficient evidence to determine whether three other weight-loss programmes are also effective.

Aim: To examine whether other group-based weight-loss programmes were not inferior to Weight Watchers.

Design and setting: A prospective cohort study using a non-inferiority analysis of 3290 adults referred through primary care. METHOD Participants who met the eligibility criteria for primary care obesity management treatment chose a free programme (Weight Watchers, Rosemary Conley Diet and Fitness Clubs, Slimming World or a NHS group programme) lasting 3 months; they were weighed at 3 months (programme end) and self-reported their weight at 12 months.

Results: At 3 months, weight loss achieved through Rosemary Conley and Slimming World was not inferior to Weight Watchers. The NHS group programme was inferior. At 12 months Slimming World and Rosemary Conley were not inferior to Weight Watchers, although participants using Slimming World lost significantly more weight than those using Weight Watchers. Data on the NHS group programme were inconclusive.

Conclusion: In the short term all commercial weight-loss programmes appear to result in similar weight loss but the NHS alternative appears to produce less weight loss. At 12 months Slimming World led to greater weight loss but the differences between commercial programmes was small and of minor clinical importance.

Keywords: obesity; primary health care; weight loss; weight reduction programmes.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cohort Studies
  • Diet, Reducing* / methods
  • Exercise*
  • Health Promotion
  • Humans
  • Obesity / epidemiology
  • Obesity / prevention & control*
  • Obesity / psychology
  • Patient Acceptance of Health Care / psychology
  • Patient Acceptance of Health Care / statistics & numerical data*
  • Patient Satisfaction
  • Primary Health Care*
  • Program Evaluation
  • Prospective Studies
  • Treatment Outcome
  • United Kingdom
  • Weight Loss*
  • Weight Reduction Programs* / methods