Nature-based activities to support mental ill health
| ISRCTN | ISRCTN12900725 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN12900725 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Integrated Research Application System (IRAS) | 330630 |
| Protocol serial number | CPMS 57053, Grant Code: NIHR208091 |
| Sponsor | University of Exeter |
| Funder | National Institute for Health and Care Research |
- Submission date
- 20/06/2025
- Registration date
- 04/07/2025
- Last edited
- 04/07/2025
- Recruitment status
- Recruiting
- Overall study status
- Ongoing
- Condition category
- Mental and Behavioural Disorders
Plain English summary of protocol
Background and study aims
There is increasing evidence that taking part in activities in nature, such as gardening or conservation, has positive impacts on people’s health and well-being. These types of activities can be offered to people through social prescribing, where people can be referred to community activities as part of their treatment. Although there are a large number of nature-based social prescribing projects, few have been evaluated using the most robust methods. Healthcare commissioners are increasingly seeking high-quality evidence of the effectiveness of nature-based activities. Randomised controlled trials (RCTs) are widely accepted as the most reliable way to demonstrate effectiveness. This type of evaluation will support more confident decision-making around funding and help ensure that people with mental health needs are referred to the most appropriate interventions for them.
This study will be a pilot RCT. Before undertaking a full trial, it is important to ensure the plans for that research are feasible, appropriate and acceptable, so that the outcomes of the RCT will be meaningful. A pilot allows us to test the proposed research processes (for example, that we are able to recruit enough people and that the questionnaires used to measure impact are appropriate). We will collect quantitative data on impacts and speak to participants and the nature-activity providers to understand what works well and what could be improved. The pilot will recruit people to the study and randomise them to receive a 6-week nature-based activity or to a comparison group. Changes in their mental health, wellbeing, loneliness and health services use will be compared between these two groups. The comparison group will then also be offered the chance to take part in nature-based activities.
The outcome of the study will be a detailed plan for a future RCT which will assess the effectiveness and cost-effectiveness of nature-based activities for people with mental ill-health.
Who can participate?
Adults aged 18 years and over with mild to moderate depression and/or anxiety who live within travelling distance of the activity sites
What does the study involve?
Adults living with mild to moderate depression and/or anxiety will be invited to join the study via targeted emails or texts from their GPS, referrals from link workers who work with the activity providers, social media advertisements, or they may hear about the study informally via friends and family. Participants will be randomly allocated to either the intervention group or the wait-list control group. Once randomised, the participants will be asked to fill in a set of baseline questions on their mental health, wellbeing, loneliness and health service use, and on their personal characteristics. The intervention group will take part in a 3-hour session of nature-based activities once a week for 6 weeks. All participants will then be asked to fill in the same questions asked at baseline when the activities end, and then again 6 weeks later. Once all the data has been collected, the wait list control group will be able to take part in the nature-based activities. Participants will also be invited to take part in focus groups to help us understand their experiences.
What are the possible benefits and risks of participating?
Participants in both groups will receive a 6-week nature-based programme of activities (an approximately 3-hour session once a week) designed to help manage mild to moderate depression and/or anxiety.
Potential risks of the study may include distress linked to reflection on the issues raised by the data collection tools. All activities will take place outdoors, and there may be inclement weather and minor injuries related to walking and the use of gardening equipment. Participants may enjoy and feel benefit from the nature-based activities they do in the intervention, and not want these to end after the research study.
Where is the study run from?
European Centre for Environment and Human Health, University of Exeter, Faculty of Health and Life Sciences (UK)
When is the study starting and how long is it expected to run for?
October 2024 to March 2026
Who is funding the study?
National Institute for Health and Care Research (NIHR) (UK)
Who is the main contact?
1. Prof. Ruth Garside, R.Garside@exeter.ac.uk
2. Dr Rebecca Lovell, r.lovell@exeter.ac.uk
Contact information
Principal investigator
ECEHH
Faculty of Health and Life Sciences
Peter Lanyon Building
Penryn
TR10 8RD
United Kingdom
 ORCID ID |
0000-0003-1649-4773 |
|---|---|
| Phone | +44 (0)1872 258148 |
| R.Garside@exeter.ac.uk |
Scientific
ECEHH
Faculty of Health and Life Sciences
Peter Lanyon Building
Penryn
TR10 8RD
United Kingdom
| ORCID ID |
0000-0002-6962-0350 |
|---|---|
| Phone | +44 (0)1872 258148 |
| r.lovell@exeter.ac.uk |
Scientific
NIHR ARC South-West Peninsula (PenARC)
Faculty of Health
University of Plymouth
Plymouth
PL4 8AA
United Kingdom
| ORCID ID |
0000-0001-5674-8673 |
|---|---|
| Phone | +44 (0)1752 764260 |
| kerryn.husk@plymouth.ac.uk |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Randomized; Both; Design type: Treatment, Complex Intervention, Other, Qualitative |
| Secondary study design | Randomised controlled trial |
| Study type | Participant information sheet |
| Scientific title | Nature on prescription to support mental ill health (GREENGAGE): a pilot randomised controlled trial and process evaluation |
| Study acronym | GREENGAGE |
| Study objectives | Primary study hypothesis: The mild to moderate depression and/or anxiety of people receiving nature-based therapeutic activities improves to a greater degree than a control group not receiving the activities. Study feasibility and testing hypotheses: 1. The study recruitment strategies and enrolment procedures are acceptable and feasible 2. The intervention is acceptable to participants and delivery organisations 3. The process of recruitment is feasible 4. The process of allocation to intervention or waitlist control group is acceptable and feasible 4. Retention of the control group (waitlist) is sufficient 5. Adherence to and fidelity of trial procedures are sufficient |
| Ethics approval(s) |
Approved 27/05/2025, Wales REC7 (Health and Care Research Wales, Castlebridge 4, 15-19 Cowbridge Road East, Cardiff, CF11 9AB, United Kingdom; +44 (0)2922 941107, +44 (0)2922 940968; Wales.REC7@wales.nhs.uk), ref: 25/WA/0125 |
| Health condition(s) or problem(s) studied | Mental health |
| Intervention | The participation process for individuals will be: 1. Reading the project PIS. 2. Opportunity to discuss the project with the research team. 3. Initial suitability for location and timing of nature-based activities. 4. Completion of the screening tool to determine eligibility. 5. Completion of the consent form 6. Completion of the baseline questionnaires (T0) for all participants (Participant characteristics; Mental health and wellbeing measures; Health service use questionnaire). 7. Random allocation to either the intervention group (nature-based activities) or the control group (usual care, wait list). 8. Those allocated to the intervention group will participate in a 6-week programme of nature-based activities. An initial optional induction session prior to the first group session will also be available. 9. Completion of questionnaires for all participants (6 weeks post-intervention start [T1] and 12 weeks post [T2]): (Mental health and wellbeing measures; Loneliness measure; Health service use questionnaire). 10. Participation in a focus group discussion about their experience of the pilot trial (optional). 11. Those allocated to the control group will be offered the opportunity to take part in a 6-week programme of nature-based activities after the follow-up period. |
| Intervention type | Behavioural |
| Primary outcome measure(s) |
1. Anxiety is measured using the Generalised Anxiety Score scale (GAD-7) at T0 (baseline), T1 (end of intervention), and T2 (6-week follow-up). |
| Key secondary outcome measure(s) |
1. Mental wellbeing is measured using the short Warwick-Edinburgh Mental Wellbeing Scale (sWEMWBS) at T0 (baseline), T1 (end of intervention), T2 (6-week follow-up) |
| Completion date | 31/03/2026 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Sex | All |
| Target sample size at registration | 84 |
| Key inclusion criteria | 1. People aged 18 years and over 2. People with mild to moderate depression and/or anxiety assessed by scores of 10-19 on the Patient Health Questionnaire (PHQ-9) and/or 5-14 on the Generalised Anxiety Disorder assessment (GAD-7) 3. Ability to give informed consent to written information sheets and consent forms 4. Participants may be on any current treatment for mild to moderate depression and/or anxiety, or none |
| Key exclusion criteria | 1. People with severe depression and/or anxiety (as assessed by scores of 20 or more on the PHQ-9 and/or 15 or more on GAD-7) 2. People unable to understand written and verbal instructions in English 3. Those with serious physical impairment that would prevent participation in even adapted nature-based activities (such as walking, gardening, pond dipping) 4. Actively suicidal or psychotic (as assessed by the mood screener – see later details) Participants will need to have a good understanding of English to participate given that the intervention instructions, including safety instructions related to specific activities or tool use, will be given in English by the nature-based providers on the day. As these are small VCSE groups, it is not possible for staff to accommodate other languages. |
| Date of first enrolment | 16/06/2025 |
| Date of final enrolment | 31/01/2026 |
Locations
Countries of recruitment
- United Kingdom
- England
Study participating centres
Exeter
EX4 4PY
United Kingdom
Barrack Road
Exeter
EX2 5DW
United Kingdom
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|---|
| IPD sharing plan summary | Not expected to be made available |
| IPD sharing plan | The datasets generated during and/or analysed during the current study are not expected to be made available due to the small scale of the study and the risk of deanonymisation of the data. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
| Protocol file | version 3 | 02/07/2025 | 02/07/2025 | No | No |
| Study website | Study website | 11/11/2025 | 11/11/2025 | No | Yes |
Additional files
- 47530_PROTOCOL_V3_02Jul25.pdf
- Protocol file
Editorial Notes
20/06/2025: Study's existence confirmed by the NIHR.
