Condition category
Not Applicable
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
Being physically active is good for children’s health. Few adolescent girls are active enough to get these health benefits and teenage girls face lots of barriers to being physically active. Research shows that most school-based programs to increase adolescents' physical activity do not work, but few high quality studies have been tried in the UK. As children move into adolescence, friends’ opinions and activity levels become influential on their beliefs about, and levels of, physical activity. If we can harness the power of peer-influences to have a positive impact on adolescent girls’ activity, then this could be a new way to inspire girls to be active. We know that peer-led anti-smoking projects can reduce teen smoking rates. In these projects, adolescents nominate peers (who they see as influential and they respect) to be ‘peer-supporters’. These peer supporters then attend out-of-school training about smoking and return to school for 10 weeks and informally encourage their peers not to smoke. In this study we want to adapt this idea to develop a project to train girls to influence their friends’ physical activity. Before conducting large studies it is important to carefully craft the programme by including girls in its development. This helps to test whether girls find it acceptable and whether they engage well enough in our research to make a larger study worthwhile.

Who can participate?
Year 8 girls in participating schools.

What does the study involve?
We will develop and test whether it is possible to run a school-based peer-led physical activity project for 12-13 year old girls. We will develop the project by speaking with adolescent girls about how they would design the training and the wording they use. The project will follow similar processes to the smoking cessation study. Peer supporters will be trained by experts in physical activity and youth work. We will practice the project in one school to find any problems and then do a larger test of the project in six schools. Four schools will be chosen at random to run the peer-training project and two schools will be “comparison schools” and will not do the peer-training. Year 8 girls in all six schools will be asked to provide information at three times: before the schools are chosen to be project or comparison schools, straight after the 10-week project, and 1 year after the first measurements. We are mainly interested in finding out whether we can recruit girls into the project and whether the data collection, peer-nomination and training, and 10-week informal discussion periods are successful. We will measure the girls’ activity levels using activity monitors and their motivation for being active using questionnaires. We will do interviews and group discussions with peer-supporters, pupils, parents, and trainers to find out what was successful and what could be changed in future.

What are the possible benefits and risks of participating?
The benefits of participation for peer-supporters include an increased awareness of physical activity and the health benefits of being more active, improved teamwork, communication, empathy and problem solving skills, and a potential increase in physical activity levels due to the ideas and knowledge gained during the training and intervention period. The benefits of participation for Year 8 girls who are not peer-supporters include being encouraged to be more active from their peers, greater exposure to new ideas about how to incorporate physical activity into their day-to-day life, and the potential health benefits this holds. Schools benefit by having a number of their pupils attending a training course which may increase their skills, confidence and leadership abilities. Additionally, physical activity levels throughout the Year 8 female cohort may be increased. The potential risks to participants are minimal. Peer-supporters may face instances of bullying/teasing, but we will ensure reporting procedures are in place to minimise such instances and effectively deal with any that do arise. Non-peer-supporters may feel pressured to be active, but the training that peer-supporters receives will cover empathy and effective communication.

Where is the study run from?
University of Bristol (UK)

When is the study starting and how long is it expected to run for?
April 2015 to July 2017

Who is funding the study?
National Institute for Health Research (Public Health Research Programme) (UK)

Who is the main contact?
Dr Mark Edwards

Trial website

Contact information



Primary contact

Dr Mark Edwards


Contact details

Centre for Exercise
Nutrition and Health Sciences
School for Policy Studies
University of Bristol
8 Priory Road
United Kingdom
+44 (0)117 331 1011

Additional identifiers

EudraCT number number

Protocol/serial number

PHR 13/90/16

Study information

Scientific title

Development and feasibility cluster randomised controlled trial evaluation of a Peer-Led physical Activity iNtervention for Adolescent girls (PLAN-A)



Study hypothesis

The study is a feasibility trial and as such no hypotheses are made with regards to the effectiveness of the intervention, as that will not be formally tested. The basic working hypothesis of a potential future definitive trial would be that participation in the PLAN-A intervention will increase the physical activity of Year 8 girls.

More details can be found at:

Ethics approval

1. Phase 1: School for Policy Studies Ethics Committee, University of Bristol, 24/02/2015, ref: SPSREC14-15.A10
2. Phase 2: School for Policy Studies Ethics Committee, University of Bristol, 13/08/2015, ref: SPSREC14-15.A27

Study design

Feasibility cluster randomised controlled trial with schools as the unit of randomisation

Primary study design


Secondary study design

Cluster randomised trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details to request a patient information sheet


Physical activity


Four schools will be chosen at random to run the peer-training project and two schools will be comparison schools and will not do the peer-training.

1. Peer-nomination:
Peer-supporters will be identified by peer nomination in which consenting Year 8 girls will identify, by questionnaire, the female peers they perceive to be influential. The highest scoring 18% (those with most nominations) will be invited to be peer-supporters, with the aim of ensuring that ≥15% take on this role
2. Peer-supporter training:
Peer-supporters will attend a two-day course to develop the skills, knowledge and confidence to promote physical activity amongst their peers. Training will be held off-site and led by external peer-supporter educators who themselves will have attended a 3-day training programme. The peer-supporter training will be informed by our developmental work with Year 8 girls, will be interactive and address issues central to girls’ PA, including: PA benefits, active choices, developing an active identity, being active with friends, sedentary behaviour, communicating with confidence, empathy and supporting motivation. The content will be grounded in self-determination theory to build the girls’ perceived autonomy, competence and sense of social support, both for being a peer-supporter and to promote physical activity. Peer-supporters will be encouraged to keep these concepts in mind when having conversations with their peers.
3. 10-week informal health message peer-diffusion component:
Peer-supporters will informally promote messages about increasing physical activity amongst their peers for 10 weeks. At the mid-point of the intervention peer-supporters will attend a 1 day off-site top-up session to revisit core messages, share successes and collaboratively resolve problems.

Year 8 girls in all six schools will be asked to provide information at three times: before the schools are chosen to be project or comparison schools, straight after the 10-week project, and 1 year after the first measurements.

Intervention type



Drug names

Primary outcome measure

1. Recruitment and retention rates of peer-supporters and non-peer supporter Year 8 girls (measured between September 2015 - March 2016, approximately)
2. Data provision rates, in order to estimate questionnaire and accelerometer provision rates for a full trial (measured between September 2015 and November 2016)
3. Acceptability of the training and intervention to stakeholders (peer-supporters, pupils, parents, peer-educators and schools) (measured post-intervention, between March-May 2016, approximately)
4. Feasibility of gathering the permissions needed to conduct data linkage to long-term outcomes (between September 2015-December 2017)
5. Feasibility of collecting information needed to conduct a cost-effectiveness analysis of the intervention (measured throughout the intervention period, approximately January-April 2016)

Secondary outcome measures

1. Accelerometer-determined daily minutes of moderate-to-vigorous physical activity. This is the likely primary outcome in a definitive trial
2. Self-reported mode of travel to school (active vs passive)
3. Self-reported leisure-based sedentary behaviour
4. Self-esteem, health-related quality of life and potential mediators of the intervention (such as self-determined physical activity motivation and peer-norms) will be assessed

All secondary outcomes will be measured at three time points: September 2016 - November 2015; March-April 2016; September-November 2016

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Year 8 girls in participating schools

Participant type


Age group




Target number of participants


Participant exclusion criteria

No participant exclusion criteria

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

University of Bristol
Centre for Exercise, Nutrition and Health Sciences School for Policy Studies 8 Priory Road
United Kingdom

Sponsor information


University of Bristol (UK)

Sponsor details

Research and Enterprise Development
3rd Floor
Senate House
Tyndall Avenue
United Kingdom
+44 (0)117 928 8676

Sponsor type




Funder type


Funder name

Public Health Research Programme

Alternative name(s)

NIHR Public Health Research Programme, PHR

Funding Body Type

government organisation

Funding Body Subtype

National government


United Kingdom

Results and Publications

Publication and dissemination plan

We plan to publish a study protocol paper and the results of the main feasibility trial and process evaluation in one or two papers, as appropriate. Any other publications will be dependent on the results of the feasibility study.

Depending on the results of the study, the intervention may be trialled on a larger scale and could, depending on results of a definitive trial, be disseminated widely. Results will be shared with all stakeholders.

In line with the NIHR research contract, anonymised data from this study will be made available to other researchers. This will be done using the University of Bristol’s Research Data Repository.

Intention to publish date

Participant level data

Stored in repository

Basic results (scientific)

Publication list

2016 protocol in:
2016 protocol update in:
2018 results in:

Publication citations

Additional files

Editorial Notes

11/06/2018: Publication reference added. 07/12/2016: Publication reference added. 24/03/2016: Ethics approval information added. 20/01/2016: Publication reference added.