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Outcomes and costs of primary care surveillance and intervention for overweight or obese children: the LEAP 2 randomised controlled trial

BMJ 2009; 339 doi: (Published 03 September 2009) Cite this as: BMJ 2009;339:b3308
  1. Melissa Wake, paediatrician1,
  2. Louise A Baur, professor2,
  3. Bibi Gerner, research officer1,
  4. Kay Gibbons, head of Nutrition and Food Services1,
  5. Lisa Gold, health economist4,
  6. Jane Gunn, professor3,
  7. Penny Levickis, research assistant1,
  8. Zoë McCallum, paediatrician1,
  9. Geraldine Naughton, director5,
  10. Lena Sanci, research fellow3,
  11. Obioha C Ukoumunne, statistician1
  1. 1Royal Children’s Hospital, Murdoch Childrens Research Institute and University of Melbourne, Parkville, Vic 3052, Australia
  2. 2Discipline of Paediatrics and Child Health, University of Sydney and the Children’s Hospital at Westmead, Westmead, NSW 2145, Sydney, Australia
  3. 3Department of General Practice, University of Melbourne
  4. 4Health Economics Unit, School of Health and Social Development, Deakin University, Burwood, Vic 3125, Australia
  5. 5Centre of Physical Activity Across the Lifespan, School of Exercise Science, Australian Catholic University, Strathfield NSW 2135, Australia
  1. Correspondence to: M Wake, Centre for Community Child Health, Royal Children’s Hospital, Flemington Rd, Parkville, Vic 3052, Australia melissa.wake{at}
  • Accepted 14 April 2009


Objective To determine whether ascertainment of childhood obesity by surveillance followed by structured secondary prevention in primary care improved outcomes in overweight or mildly obese children.

Design Randomised controlled trial nested within a baseline cross sectional survey of body mass index (BMI). Randomisation and outcomes measurement, but not participants, were blinded to group assignment.

Setting 45 family practices (66 general practitioners) in Melbourne, Australia.

Participants 3958 children visiting their general practitioner in May 2005-July 2006 were surveyed for BMI. Of these, 258 children aged 5 years 0 months up to their 10th birthday who were overweight or obese by International Obesity Taskforce criteria were randomised to intervention (n=139) or control (n=119) groups. Children who were very obese (UK BMI z score ≥3.0) were excluded.

Intervention Four standard consultations over 12 weeks targeting change in nutrition, physical activity, and sedentary behaviour, supported by purpose designed family materials.

Main outcomes measures Primary measure was BMI at 6 and 12 months after randomisation. Secondary measures were mean activity count/min by 7-day accelerometry, nutrition score from 4-day abbreviated food frequency diary, and child health related quality of life. Differences were adjusted for socioeconomic status, age, sex, and baseline BMI.

Results Of 781 eligible children, 258 (33%) entered the trial; attrition was 3.1% at 6 months and 6.2% at 12 months. Adjusted mean differences (intervention − control) at 6 and 12 months were, for BMI, −0.12 (95% CI −0.40 to 0.15, P=0.4) and −0.11 (−0.45 to 0.22, P=0.5); for physical activity in counts/min, 24 (−4 to 52, P=0.09) and 11 (−26 to 49, P=0.6); and, for nutrition score, 0.2 (−0.03 to 0.4, P=0.1) and 0.1 (−0.1 to 0.4, P=0.2). There was no evidence of harm to the child. Costs to the healthcare system were significantly higher in the intervention arm.

Conclusions Primary care screening followed by brief counselling did not improve BMI, physical activity, or nutrition in overweight or mildly obese 5-10 year olds, and it would be very costly if universally implemented. These findings are at odds with national policies in countries including the US, UK, and Australia.

Trial registration ISRCTN 52511065 (


  • Contributors: The project was initiated and supervised by MW, JG, LAB, ZM, and KG, who also obtained its funding. All authors contributed to developing the protocols and reviewing, editing, and approving the final version of the paper. The trial was implemented by MW, ZM, and BG, who oversaw all stages. BG and PL carried out recruitment and data collection, with other field workers. LS, Colin Riess, and Helen Cahill contributed medical education planning, implementation, and expertise. Lucy Rogers and Rachel Barratt contributed to recruitment, retention, and data collection from families and general practitioners. OCU conducted the analyses, with the exception of the economic analysis, which was performed by LG. MW and BG wrote the paper, with critical input from the other authors. MW is the guarantor. We thank Colin Riess, Helen Cahill, Lucy Rogers, and Rachel Barratt for their contributions to the project.

  • Funding: This study was funded by the Australian National Health and Medical Research Council (NH&MRC) Project Grant 334309. MW is supported by NH&MRC Career Development Award 284556; LG by NH&MRC Capacity Building Grant 425855; and OCU by NH&MRC Capacity Building Grant 436914. The researchers were independent of the funders.

  • Competing interests: None declared.

  • Ethical approval: The project was approved by the Royal Children’s Hospital Ethics in Human Research Committee (EHRC 25006).

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