Is Halo plus usual care (usual STI prevention information provided by STI testing websites) effective and cost-effective in reducing STI positivity amongst 16 24-year-olds at 12 months in comparison to usual care only?

To determine whether adding Halo to usual care reduces chlamydia positivity at 12 months.

1. to determine whether adding Halo to usual care reduces gonorrhoea positivity at 12 months
2. to determine whether adding Halo to usual care reduces repeat infections or (cumulative) incidence of chlamydia or gonorrhoea
3. to determine whether adding Halo to usual care increases the frequency of correct and consistent condom use during vaginal and/or anal sexual intercourse
4. to examine whether STI and behavioural outcomes differ by subgroup (ethnicity, sexual orientation, and deprivation)
5. to determine whether the effect of Halo on STI outcomes is mediated by changes in the targeted behaviour and behavioural determinants
6. to determine whether adding Halo to usual care is cost-effective and analyse impacts on equity
7. to describe the level and patterns of engagement with Halo, and to identify whether patterns of engagement differ by subgroup (ethnicity, sexual orientation, and deprivation)
8. to determine whether STI and behavioural outcomes differ by patterns of engagement with Halo

Design: A two-arm parallel group randomised controlled trial (RCT) of Halo plus usual care compared to usual care only, with nested process evaluation. Participants will be randomised into one of two parallel groups (1:1 allocation). We will collect health economic data to compare the resource costs and cost effectiveness of delivering Halo compared to usual care.

Setting: Participants will be recruited from STI self-sampling websites.

Participants: A minimum of 3,576 participants (aged 16-24 years) will be recruited over 18 months.

Measures:

• month 0: online survey, STI test result
• month 3: online survey, STI test kit
• month 6: online survey
• month 12: online survey, STI test kit.

A Study Within A Trial (SWAT) will test the effectiveness and cost-effectiveness of offering choice of gift voucher incentive for increasing participant recruitment and retention rates in the Halo Trial.

The Halo SWAT objectives are:

1. to evaluate the effectiveness of offering potential participants a choice of gift vouchers from different retailers (intervention group) compared to not offering a choice of gift vouchers (control group) for increasing participant recruitment rates in the Halo Trial
2. to evaluate the effectiveness of offering participants a choice of gift vouchers from different retailers (intervention group) compared to not offering a choice of gift voucher (control group) for improving retention rates in the Halo Trial
3. to evaluate the cost-effectiveness of the voucher choice strategy on participant recruitment and retention rates.

Implement SWATs (sponsored by the University of York and funded by the NIHR; Advanced Fellowship, ref: NIHR302256) is collaborating with the Halo trial team to provide support for this SWAT, as part of its coordinated SWATs programme.

The nested process evaluation will estimate future levels of Halo uptake and use. For this, up to 300 users of web-based STI self-sampling services will be given access to Halo for three months (outside the confines of the RCT) and usage tracked using data analytics. In order to understand different patterns of engagement with Halo and young people's perceptions on whether Halo has had an impact on their condom use, up to 30 participants will be sampled from users of the process evaluation. Semi-structured interviews will be recorded and transcribed prior to reflexive thematic analysis.

We will assess the readiness and ability of web-based STI self-sampling providers to implement Halo using an implementation tool designed for e-health interventions (e-HIT).

Should Halo be established as cost-effective, an in-person implementation stakeholder meeting will be held to reflect on current commissioning and service delivery, discuss current implementation issues, and generate a road map for implementation. Potential impact includes reduced STI positivity, improved sexual health and quality of life, reduced costs of STI treatment, and reduced health inequality. We have a robust plan for project dissemination including multi-media communication with stakeholders, academics and the public.

• November 2024- June 2025: study set up; website optimisation and set up; ethical approval
• July 2025-December 2027: recruitment begins; data collection
• July 2027-December 2027: nested process evaluation
• January 2028-July 2028: analysis; stakeholder impact mapping
• August 2028-October 2028: report writing and dissemination.

Public involvement is ‘an active partnership between patients, carers and members of the public with researchers that influences and shapes research’ (NIHR).

Young people, who are affected by research, have a right to have a say in how it is done. There are benefits to involvement for both research and young people, in providing opportunities to influence research that is relevant to their lives and those of their peers. Young people provide different perspectives, can help ensure research is relevant to their peers, and improve the design and conduct of health research.

More information:

• NIHR involving children and young people as advisors in research
• Brady, L-M et al. (2023). “We know that our voices are valued, and that people are actually going to listen”: co‑producing an evaluation of a young people’s research advisory group. Research Involvement and Engagement, 9 (11)
• Enabling the meaningful participation of children and young people globally: The Lundy Model

The involvement of young people is central to the Halo project and includes:

• Two young co-investigators (Kanika and Tia), who were involved in the application for funding, sit on the trial management group and work with the team to plan and support the young people’s advisory group (YPAG).
• The project YPAG: 12 young people aged 16-24, with a range of diverse experience and backgrounds, who meet regularly throughout the project to provide advice and input to the research team.
• Two members of the young people's advisory group sitting on the trial steering committee.

The work of the YPAG includes:

• contributing to the development of recruitment and data collection materials
• reviewing and refining methods to ensure that they are accessible, inclusive and age-appropriate
• supporting data analysis
• input into design of the project website
• contributing to reporting and dissemination (e.g. newsletter articles and blog posts, co-authoring publications, co-producing creative outputs and co-presenting at conferences and events)

If you’re interested in finding out more about the YPAG, or are interested in joining, please contact halo@herts.ac.uk