Using digital technology to support people living with obesity

ISRCTN ISRCTN89168871
DOI https://doi.org/10.1186/ISRCTN89168871
IRAS number 355370
Secondary identifying numbers PH648124, NIHR208100, CPMS 69222
Submission date
06/08/2025
Registration date
04/09/2025
Last edited
04/09/2025
Recruitment status
Recruiting
Overall study status
Ongoing
Condition category
Nutritional, Metabolic, Endocrine
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
Obesity affects over a quarter of the UK population and can lead to serious health issues. NHS Specialist Weight Management Services (WMS) offer treatments including lifestyle advice, psychological support, and medications, but access and availability vary by region. Although around 4 million people could be eligible for NHS Specialist WMS annually, capacity is limited to 35,000, severely limiting overall access for those who need it. While digital technology has started to be used in WMS, more evidence is needed to confirm its long-term effectiveness, acceptability, and cost-effectiveness. This study explores the use of Gro Health W8Buddy, a digital platform and app providing remote Specialist WMS. It aims to determine the long-term health benefits of the remote WMS pathway Gro Health W8Buddy compared to standard NHS WMS delivered in hospitals, and to improve patients' access to services.

Who can participate?
Adult patients with obesity class 2 and at least 1 medical complication (e.g., prediabetes, type 2 diabetes) or patients with obesity class 3 (BMI ≥40 kg/m²), without complication.

What does the study involve?
The study is a real-world evaluation with observational data collection. Study participants will be recruited from four NHS specialist WMS who will choose either the standard NHS WMS or the digital pathway Gro Health W8Buddy. The study will measure and analyse health outcomes, including weight loss, time taken to be treated and cost-effectiveness, at 18 and 24 months. It will gather experiential data from patients and healthcare professionals through surveys, observation, and interviews.
The study is structured around four distinct work packages, each employing a unique research methodology. The digital intervention has been co-created with NHS staff and patients and is backed by research. This research methodology has been shaped by PPI input from all four NHS sites. The study methods enable Real World Evidence to be generated by allowing participants to choose their pathway and will therefore provide credible evidence for further roll-out of digital technology in weight management services across the UK. Allocation is, by design, not randomly allocated, which may lead to more participants in digital care or vice versa.

What are the possible benefits and risks of participating?
No benefits and risks given at registration

Where is the study run from?
University of Warwick, UK

When is the study starting and how long is it expected to run for?
November 2024 to October 2027

Who is funding the study?
National Institute for Health and Care Research (NIHR) (UK)

Who is the main contact?
Dr Petra Hanson, Petra.hanson.1@warwick.ac.uk

Contact information

Dr Petra Hanson
Scientific

Warwick Medical School
University of Warwick
Coventry
CV4 7AL
United Kingdom

Phone +44 (0)2476966581
Email Petra.hanson.1@warwick.ac.uk
Dr Thomas Barber
Principal Investigator

Warwick Medical School
University of Warwick
Coventry
CV4 7AL
United Kingdom

Phone +44 (0)2476966581
Email t.barber@warwick.ac.uk
Dr Jonathan Hazlehurst
Principal Investigator

University Hospitals Birmingham
Mindelsohn Way
Birmingham
B15 2GW
United Kingdom

Phone +44 (0)2476966581
Email jonathan.hazlehurst3@uhb.nhs.uk
Dr Akhila Mallipedhi
Principal Investigator

Hywel Dda Health Board
1 Penlan Road
Carmarthen
SA31 1DS
United Kingdom

Phone +44 (0)2476966581
Email akhila.mallipedhi@wales.nhs.uk
Mr Richard Green
Public

UHCW
CLifford Bridge Road
Coventry
CV2 2DX
United Kingdom

Phone +44 (0)2476966581
Email Richard.Green@uhcw.nhs.uk
Miss Manreet Thind
Scientific

UHCW
Clifford Bridge Road
Coventry
CV2 2DX
United Kingdom

Phone +44 (0)2476966581
Email Manreet.Thind@uhcw.nhs.uk
Dr Anjali Zalin
Principal Investigator

NHS Bedfordshire, Luton and Milton Keynes, The Mall
Luton
LU1 2LJ
United Kingdom

Email anjali.zalin3@nhs.net
Prof Amy Grove
Scientific

University of Birmingham, Park House, Edgbaston Park Road
Birmingham
B15 2RT
United Kingdom

Email a.l.grove@bham.ac.uk

Study information

Study designMulti-centre prospective observational cohort study
Primary study designObservational
Secondary study designCohort study
Study setting(s)Hospital
Study typeTreatment
Participant information sheet Not available in web format, please use the contact details to request a participant information sheet
Scientific titleLong-term health and economic impact of using digital tool Gro Health W8Buddy to support people accessing specialist weight management services
Study acronymW8Buddy Study
Study objectivesTo determine changes in body weight after 18 months of using either (i) a fully digital weight management program (remote digital pathway Gro Health W8Buddy) or (ii) site-specific delivered weight management programs incorporating face-to-face and/or virtual group sessions (standard care). Both programmes will deliver weight loss medication in line with usual medication provision as determined in local services.
Ethics approval(s)

Approved 14/07/2025, Leicester South REC (3 Piccadilly Place, London Road, Manchester, M1 3BN, United Kingdom; +44 (0)2071048193; leicestersouth.rec@hra.nhs.uk), ref: 25/EM/0147

Health condition(s) or problem(s) studiedClass 2 obesity (BMI ≥35 kg/m²) with at least one medical complication (e.g., prediabetes, type 2 diabetes [T2DM]); or patients with obesity class 3 (BMI ≥40 kg/m2), without any complications.
InterventionW8Buddy is a virtual specialist WMS pathway. It is accessed through a digital behavioural change platform called the Gro Health app. Participants will either use (i) a fully digital weight management program (remote digital pathway Gro Health W8Buddy) or (ii) site-specific delivered weight management programs incorporating face-to-face and/or virtual group sessions (standard care). Both are 18-month programmes that will deliver weight loss medication in line with usual medication provision as determined in local services.

This is a multi-site prospective comparative observational cohort study with embedded cost-effectiveness analysis and process evaluation, comprising four work packages (WP) to assess the following:
1. Set up, Patient and Public Involvement and Engagement (PPIE) & Stakeholder engagement
2. Clinical impact
3. Health economic impact
4. Process evaluation

The W8Buddy app provides personalised WMS to support patients in achieving their self-selected health goals and support weight loss with real-time remote monitoring. The digitally enabled WMS service at UHCW uses W8Buddy and augments traditionally delivered NHS care. The key features of W8Buddy include provision of one-to-one services by a medically qualified obesity specialist (specialist dietitian, psychologist and a GP with a special interest in weight management), clinical support via a multi-disciplinary team (MDT), group work (e.g. education modules, virtual sessions) and behaviour change activities, plus signposting to local and national services. The digital pathway is delivered through app contents, in-app chat, video teleconferencing and telephone. Prescribing is led by a Clinical Pharmacist who has an appointment with the patient during Week 1. There are then monthly medication reviews for the first 6 months and then every 12 weeks. Medication tracking is supported in the W8Buddy application. Side effects can be logged through the W8Buddy application and are discussed at the medication reviews that take place. Individualised support will be offered to those people who do not have access to a digital device, as appropriate to their needs.
Intervention typeBehavioural
Primary outcome measureBody weight measured using specialist scales provided as part of the digital pathway or specialist scales used in NHS sites as part of standard of care at baseline and months 6, 12, 18 and 24, with reporting at month 18
Secondary outcome measures1. Cost-effectiveness of W8Buddy measured using validated tools recommended by a health economist at baseline and months 6, 12, 18 and 24, with reporting at month 18
2. The Impact of W8Buddy on multiple long-term conditions associated with obesity, measured using mixed methods approaches including surveys and interviews at baseline and months 6, 12, 18 and 24, with reporting at month 18
3. Implementation and use of W8Buddy within Weight Management Services (WMS), measured using mixed methods approaches including surveys and interviews at baseline and months 6, 12, 18 and 24, with reporting at month 18
4. Manual for safe incorporation of a digital pathway delivering weight loss medication into existing WMS across the UK, created using mixed methods approaches, including surveys and interviews throughout the duration of the study
5. Recommendations for how we can optimise the existing infrastructure of WMS to improve ongoing RWE generation, created using mixed methods approaches, including surveys and interviews throughout the duration of the study
Overall study start date01/11/2024
Completion date31/10/2027

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
Upper age limit100 Years
SexBoth
Target number of participants450
Key inclusion criteria1. Adults aged 18 years and above
2. Class 2 obesity (BMI ≥35 kg/m²) with at least one medical complication (e.g., prediabetes, type 2 diabetes [T2DM]); or patients with obesity class 3 (BMI ≥40 kg/m²), without any complications.
Key exclusion criteria1. Pregnant or breastfeeding
2. Type 1 diabetes mellitus
3. End-stage renal disease (eGFR <15, receiving renal replacement therapy)
4. Active or untreated alcohol or drug dependency
5. Decompensated liver disease
6. History of anorexia, undergoing treatment or awaiting treatment for DSM-V classified eating disorder
7. Severe mental health disease, including acute mental health crisis or self-harm in the last 12 months
8. Unstable mental health disease, including unstable personality disorder, schizophrenia and bipolar disorder
9. Unwilling or unable to commit to participation across the length of the research study
10. Patients targeting bariatric surgery within the length of the research study
11. Participating in another weight management research intervention
12. Participating in the diabetes remission program
Date of first enrolment01/09/2025
Date of final enrolment28/02/2026

Locations

Countries of recruitment

  • England
  • United Kingdom
  • Wales

Study participating centres

University Hospitals Coventry and Warwickshire NHS Trust
Walsgrave General Hospital
Clifford Bridge Road
Coventry
CV2 2DX
United Kingdom
University Hospitals Birmingham NHS Foundation Trust - Oxford Covid19 Trials
Queen Elizabeth Hospital
Edgbaston
Birmingham
B15 2TH
United Kingdom
Bedfordshire Hospitals NHS Foundation Trust
Lewsey Road
Luton
LU4 0DZ
United Kingdom
Hywel Dda Uhb, Prince Philip Hospital
Bryngwyn Mawr, Dafen
Llanelli
SA14 8QF
United Kingdom

Sponsor information

University of Warwick
University/education

University of Warwick
Coventry
CV4 7AL
England
United Kingdom

Phone +44 (0)2476575386
Email Sponsorship@warwick.ac.uk
Website https://warwick.ac.uk/
ROR logo "ROR" https://ror.org/01a77tt86

Funders

Funder type

Government

National Institute for Health and Care Research
Government organisation / National government
Alternative name(s)
National Institute for Health Research, NIHR Research, NIHRresearch, NIHR - National Institute for Health Research, NIHR (The National Institute for Health and Care Research), NIHR
Location
United Kingdom

Results and Publications

Intention to publish date31/12/2027
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryData sharing statement to be made available at a later date
Publication and dissemination planStudy results will be disseminated to all study participants in the form of regular updates via website, email or telephone should they opt for that form of communication.
IPD sharing planThe data sharing plans for the current study are unknown and will be made available at a later date.

Editorial Notes

06/08/2025: Study's existence confirmed by National Institute for Health and Care Research (NIHR) (UK).