Condition category
Infections and Infestations
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Young people in the UK report higher levels of unsafe sex than any other age group. As a result, they are at highest risk of getting, and passing on, sexually transmitted infections. Young people often lack awareness of the risks or are unsure how to protect themselves. They are also vulnerable to social pressure from friends and peers who seem more sexually experienced, and to popular beliefs that safer sex behaviour is ‘uncool’. Youth peer-led interventions often involve peers 'teaching' friends or younger children. Peer educators often volunteer themselves for this role or are chosen by teachers; this type of selection tends to result in young people who are committed to school and who may find it difficult to relate to students who are disengaged and at highest risk. An alternative is to recruit young people from among those voted as most influential by their peers, and to train them not as peer educators but as peer supporters. These individuals then act as role models who change behavioural norms through social networks and other mechanisms of influence. This has been tried, with success, in a school-based anti-smoking intervention called ASSIST. Early research on the use of social media in promoting healthy behaviour is promising. Most UK teens are connected to online social networks; messages can spread rapidly; and social media provides an alternative to talking about sex directly, something many youth find embarrassing. We will build on components found to work well in ASSIST: recruiting influential peers, allowing knowledge and attitudes to spread via social networks, and using professionals to train peer supporters. However, this intervention focuses on sexual health, an older target group and utilises social media to spread messages. The main aim of this study is to find out whether this intervention is feasible, acceptable and implemented as intended. The study is not big enough to tell us whether the intervention works, but will let us to assess whether it is worth doing a larger trial, and if yes, how we should go about doing this.

Who can participate?
All S4 students (aged 14-16) at state-funded schools in the Lothian region of Scotland who have received or are currently receiving teacher-led sex RSHP (Relationships, Sexual Health and Parenting), regardless of their sexual experience or individual level of risk.

What does the study involve?
We identify and recruit the most influential students in fourth year (S4) of secondary school. These students attend a two-day training course run by specialist trainers. Over a defined period (between 4 and 10 weeks) they use social media and face-to-face interaction to influence sexual norms and behaviour among their peers. They are supported – through regular meetings and via social media – by the professionals who trained them. After a test in one school we implement the intervention in a further six schools, using the previous group of S4 students as controls; these students move to S5 before the intervention starts and are therefore not be exposed to it. We examine how the intervention was implemented by evaluating activities, and by talking to students, teachers and parents about their experience of being involved. We are interested in whether the intervention improves attitudes, knowledge, and risk-reduction skills, and whether these, in turn, delay first sex, increase condom use and improve the quality of sexual relationships. Peer supporters present the findings to their year group, teachers, and other professionals, and we write up the results for academic and policy audiences. If the intervention is successful, we will seek funds for a full-scale study.

What are the possible benefits and risks of participating?
Not provided at time of registration

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

When is the study starting and how long is it expected to run for?
January 2016 to December 2018

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

Who is the main contact?
Dr Kirstin Mitchell

Trial website

Contact information



Primary contact

Dr Kirstin Mitchell


Contact details

MRC/CSO Social and Public Health Sciences Unit
Institute of Health and Wellbeing
University of Glasgow
Top Floor
200 Renfield Street
G2 3QB
United Kingdom
+44 (0)141 353 7514

Additional identifiers

EudraCT number number

Protocol/serial number

NIHR 14/182

Study information

Scientific title

An exploratory study to test STASH (STis and Sexual Health), a peer-led intervention to prevent and reduce STI transmission and improve sexual health in secondary schools in UK



Study hypothesis

The hypothesis of this exploratory study is that the STASH intervention will be feasible, acceptable (both to target group and stakeholders), and not inferior to existing provision of sex education in schools.

The hypotheses of the STASH intervention are:
1. That secondary students, nominated as influential by their peers and trained as peer supporters, can effect improvements in sexual attitudes and behaviour among their peers.
2. That social media provides an effective means through which peer supporters can disseminate positive sexual health messages

Ethics approval

College of Medical Veterinary and Life Sciences (MVLS) Ethics committee, University of Glasgow, 23/08/2017, ref: 00160002

Study design

Intervention development and exploratory study

Primary study design


Secondary study design

Non randomised study

Trial setting


Trial type


Patient information sheet

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


Prevention of sexually transmitted infections; sexual health and well-being


Intervention development and exploratory study undertaken in two stages:
Stage 1: Develop and formatively evaluate the intervention package, recruitment strategies and evaluation tools, pilot these in one school and make refinements
Stage 2: Conduct an exploratory study in six schools in Scotland to include a feasibility trial and detailed process evaluation. This will be designed to assess whether progression criteria for a subsequent full trial are met
The trial is multi-centre as the intervention will be delivered in 6 schools

Building on learning from ASSIST (an effective peer-led anti-smoking intervention), we will identify and recruit the most influential students in fourth year (S4) of secondary schools (aged 14 to 16) in Scotland. These students will attend a two-day training run by specialist trainers. Over a defined period (between 4 and 10 weeks) they will use social media and face-to-face interaction to diffuse information, norm change and support for healthy sexual behaviour among their peers. They will be supported – through regular meetings and via social media – by the professionals who trained them.

Intervention type



Drug names

Primary outcome measure

The main outcome is attainment of progression criteria to a potential subsequent full trial. The primary intervention outcome is frequency of unprotected sex. We will also assess the feasibility and acceptability of linkage to NHS data on STI diagnosis as a longer-term outcome.

Secondary outcome measures

Secondary outcomes to be clarified during development stage but likely to include:
1. Self-reported STI diagnosis, testing and symptoms
2. Sexual behaviour
3. Relationship quality
4. Adherence to targeted behavioural norms
5. Perceptions about the behaviour of others
6. Knowledge of STI risk
7. Awareness and use of local sexual health services
8. STI prevention skills
9. Beliefs about capabilities

Process measures include feasibility, fidelity, acceptability and reach of the intervention, for example the proportion of nominated peer supporters who agreed to participate. We will assess the perceived value of peer supporters among students, the level of exposure to the intervention, and acceptability to teachers. We will also record the key costs of intervention adaptation, implementation and maintenance and we will assess the feasibility of measuring sexual quality of life and information on sexual health related health care resource use.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

State-funded schools in the Lothian region of Scotland. All S4 students (aged 14-16; male and female) at eligible schools who have received, or are currently in receipt of teacher-led sex RSHP (Relationships, Sexual Health and Parenting), regardless of their sexual experience or individual level of risk.

Participant type

Healthy volunteer

Age group




Target number of participants

700 participants and 700 controls

Participant exclusion criteria

1. Faith schools in which STASH principles conflict with religious principles/teaching on sex education
2. Students in eligible schools who refuse their consent or whose parents/carers refuse consent

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

University of Glasgow
MRC/CSO Social and Public Health Sciences Unit Top Floor 200 Renfield Street
G2 3QB
United Kingdom

Sponsor information


University of Glasgow (UK)

Sponsor details

G12 8QQ
United Kingdom

Sponsor type




Funder type


Funder name

National Institute for Health Research

Alternative name(s)


Funding Body Type

government organisation

Funding Body Subtype

Federal/National Government


United Kingdom

Results and Publications

Publication and dissemination plan

Detailed plans for dissemination of trial results to be confirmed at a later date. Indicative plans for dissemination are as follows:
1. Academic dissemination: Protocol to be published, open access in Journal of Behavioural Medicine (or equivalent). Outcome of the exploratory study to be published, open access, in a leading international journal. Process evaluation results published, open access, in journal such as Sexually Transmitted Infections. We will present details of the study design, intervention and baseline results at a national conference (such as UK Society of Behavioural Medicine). We will also disseminate findings via The Sexual Health Research Network for UK-based academic researchers.
2. Dissemination to key policy leads and practitioners: Key policy leads, including representatives from the Sex Education Forum and the Sexual Health and BBV team at the Scottish Government, will advise on effective dissemination to policy makers and practitioners.
3. We will seek to publish a plain English summary of key findings and policy recommendations on the Sex Education Forum website. We will seek invitations to speak at key stakeholder and practitioner events, such as those organised by the 'Wellbeing in Sexual Health and HIV' (WISHH) network (aimed at professionals working within sexual health and well being in Scotland) and the British Association of Sexual Health & HIV (BASHH).
4. Dissemination to the lay public: Where appropriate, press releases will accompany the publishing of academic articles. We will also make use of social media to disseminate results. We will seek to link with public events such as science festivals. Peer supporters at participating schools will be supported to present the results to their classmates during school assemblies.

Intention to publish date


Participant level data

Stored in repository

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

06/06/2018: Uploaded protocol version 1.5 14/05/2018 (not peer reviewed) 31/10/2017: Internal review. 30/08/2017: Ethics approval information has been added.