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Doctor Referral of Overweight People to a Low-Energy Treatment (DROPLET) in primary care using total diet replacement products: a protocol for a randomised controlled trial
  1. Susan A Jebb,
  2. Nerys M Astbury,
  3. Sarah Tearne,
  4. Alecia Nickless,
  5. Paul Aveyard
  1. Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford UK
  1. Correspondence to Dr Nerys M Astbury; nerys.astbury{at}


Introduction The global prevalence of obesity has risen significantly in recent decades. There is a pressing need to identify effective interventions to treat established obesity that can be delivered at scale. The aim of the Doctor Referral of Overweight People to a Low-Energy Treatment (DROPLET) study is to determine the clinical effectiveness, feasibility and acceptability of referral to a low-energy total diet replacement programme compared with usual weight management interventions in primary care.

Methods and analysis The DROPLET trial is a randomised controlled trial comparing a low-energy total diet replacement programme with usual weight management interventions delivered in primary care. Eligible patients will be recruited through primary care registers and randomised to receive a behavioural support programme delivered by their practice nurse or a referral to a commercial provider offering an initial 810 kcal/d low-energy total diet replacement programme for 8 weeks, followed by gradual food reintroduction, along with weekly behavioural support for 24 weeks. The primary outcome is weight change at 12 months. The secondary outcomes are weight change at 3 and 6 months, the proportion of participants achieving 5% and 10% weight loss at 12 months, and change in fat mass, haemoglobin A1c, low-density lipoprotein cholesterol and systolic and diastolic blood pressure at 12 months. Data will be analysed on the basis of intention to treat. Qualitative interviews on a subsample of patients and healthcare providers will assess their experiences of the weight loss programmes and identify factors affecting acceptability and adherence.

Ethics and dissemination This study has been reviewed and approved by the National Health ServiceHealth Research Authority (HRA)Research Ethics Committee (Ref: SC/15/0337). The trial findings will be disseminated to academic and health professionals through presentations at meetings and peer-reviewed journals and to the public through the media. If the intervention is effective, the results will be communicated to policymakers and commissioners of weight management services.

Trial registration number ISRCTN75092026.

  • obesity
  • diet
  • weight loss
  • primary care

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  • Contributors SAJ and PA designed the study and secured the funding. NMA and ST helped to develop the protocol. NMA is the trial manger and AN is the trial statistician.

  • Funding This research is funded by research grants from Cambridge Weight Plan Ltdand NIHR Collaboration forLeadership in Applied Health Research and Care (CLAHRC) Oxford at Oxford HealthNHS Foundation to the University of Oxford. The sponsor of the trial isthe University of Oxford. The protocol was initiated and designed by the investigators who have nopersonal financial relationships with the Cambridge Weight Plan Ltd. Although Cambridge Weight Plan were consultedand commented on the protocol, the final decisions lay with the investigators.There are no restrictions on publication of results arising from this study andthe contract between the funder and the University ensures that the fundingbody will have no input into the decisions regarding publication.

  • Competing interests SAJ and PA have led publicly funded trials in which the weight management intervention was provided free of charge by other commercial companies. They receive no personal financial benefits from these trials. NMA, ST and AN have no competing interests. Cambridge Weight Plan, as the funder of this trial, is also the manufacturer of the nutritional products used in the trial and provided the products used in the trial free of charge to the participants.

  • Ethics approval NHS Research Ethics Committee (South Central Oxford B Committee).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement For access to the data set, a formal request should be sent to theDROPLET study group. The request will only be considered when the principalresults of the study have been published.

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