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The Jack Trial

Study Design

The World Health Organisation and the authors of a number of systematic reviews recognise that teenage boys have a vital yet neglected role in reducing teenage pregnancies and that there is a pressing need for educational interventions designed especially for them. The If I Were Jack intervention aims to increase the intention of both teenage boys and girls to avoid teenage pregnancy and promote positive sexual health by reducing the prevalence of unprotected sex. The intervention addresses gender inequalities in RSE provision by explicitly focusing on young men and teenage pregnancy. The proposed effectiveness trial will be a continuation of a programme of work. It builds upon the team’s successful feasibility trial, and their earlier Knowledge Translation Award from the ESRC (through which the intervention was initially developed), as well as a ‘translation study’ offering insights into generating an intervention that is culturally generalisable across the United Kingdom (UK).

Stage 1 was an NIHR funded feasibility Trial to test feasibility and acceptability of the intervention as well as pilot testing the trial methods.

See Results of Feasibility trial

Here is a brief summary (Published in Prevention Science)

The World Health Organisation advocates a direct focus on adolescent men in reducing adolescent pregnancy; however, no trials have been conducted. This trial (ISRCTN11632300; NCT02092480) determines whether a novel Relationship and Sexuality Educational intervention, If I Were Jack, is acceptable and feasible to implement in mixed sex UK classrooms. The intervention is a teacher-delivered intervention that emphasises male alongside female responsibility in preventing unintended pregnancies and is designed to prevent unprotected sex. The trial was a parallel-group cluster randomised controlled feasibility trial with embedded process and cost evaluation in eight secondary schools (unit of randomisation) among 831 pupils (mean age 14) in Northern Ireland, alongside a qualitative evaluation of transferability in ten schools in Scotland, Wales and England. The sampling strategy was a maximum variation quota sample designed to capture a range of school management types. Four schools were randomised to each arm and the control arm continued with usual practice. Study duration was 12 months (from November 2014), with follow-up 9 months post-baseline. Results demonstrated that the intervention was acceptable to schools, pupils and teachers, and could be feasibly implemented, cost-effectively, with minor enhancements. The between-group difference in incidence of unprotected sex (primary outcome at pupil level) of 1.3% (95% CI 0.5–2.2) by 9 months demonstrated a potential effect size consistent with those reported to have had meaningful impact on teenage pregnancy. The study responds to global health policy for a paradigm shift towards inclusion of men in the achievement of sexual and reproductive health goals in a practical way by demonstrating that a gender-sensitive as well as a gender transformative intervention targeting males to prevent teenage pregnancy is acceptable to adolescent men and women and implementable in formal education structures. If I Were Jack now merits further effectiveness testing.


Here is a lay summary (Published by NIHR)

Currently available educational approaches designed to lower unintended teenage pregnancy (UTP) focus primarily on girls.

This study aimed to trial a Relationship and Sexuality Education (RSE) teacher-delivered resource about young men and UTP called If I Were Jack in post-primary schools in Northern Ireland. The study assessed how acceptable and useful it was to teachers, pupils (male and female in mixed-sex classrooms) and parents in different types of schools and compared the findings obtained in four schools that used If I Were Jack with those in four schools that continued to use their usual approach to RSE. The study also aimed to pilot methods and to determine if it would be possible and worthwhile to conduct a large-scale UK-wide trial of the resource, which would determine if it might actually contribute to the reduction of teenage pregnancy rates.

If I Were Jack aims to help teenagers to imagine the situation of a teenage boy who has just discovered that his girlfriend has become unintentionally pregnant. It is designed to reduce UTP by encouraging teenagers to decrease sexual risk-taking behaviour that might result in unintended pregnancy either by delaying sexual intercourse or by consistently using contraception in sexual relationships.

If I Were Jack was acceptable to participating schools, pupils and parents and the study methods were suitable for collecting information from pupils. The findings also suggested that it would be possible to conduct a large-scale trial to examine the effectiveness of the resource in avoiding teenage pregnancy.



Stage 2 is an Effectiveness Trial throughout the whole of the UK (currently underway)

This is an NIHR-funded cluster randomised controlled trial (cRCT) in post-primary schools across the UK with embedded process and health economic evaluations. Sixty-six post-primary schools will participate, with schools as the unit of randomisation. Each participating pupil will be in the study for approximately 19 months and will be asked to complete a questionnaire two times – at baseline and 18 months later (12-14 months post intervention). The process evaluation will assess fidelity to implementation protocol and contextual factors associated with participation and effectiveness via semi-structured interviews with teachers, focus group discussions with pupils, a survey of parents (with potential follow-up focus group discussions), and observations of a sample of lessons. The economic evaluation will involve two components: (a) a cost-consequences analysis of trial data, and (b) a behaviour change-based decision model to evaluate the long term cost-effectiveness of the intervention.

See protocol of Trial

The aim of this trial is to assess the effectiveness of If I Were Jack in reducing unprotected sex and encouraging positive sexual health among young people.

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