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Project Title

The JACK Trial:

A phase III effectiveness multi-centre cluster randomised controlled trial of a relationship and sexuality education intervention targeted especially to young males to reduce unintended teenage pregnancy and promote positive sexual health.


Research Focus:

Maternal and Child Health 

Funder & Dates

National Institute of Health Research 2017 -2021

Principal Investigator or Primary Supervisor (if PhD project)

Professor Maria Lohan

Co-Investigators or additional supervisors

Maria Lohan,1 Áine Aventin,1 Mike Clarke,2 Lisa Maguire,1 Rachel Hunter,3 Cliona McDowell,4 Lisa McDaid,5 Honor Young,6 Jamie White,6 Adam Fletcher,6 Rebecca French,7 Chris Bonell,7 Julia Bailey,7 Liam O’Hare8


1. School of Nursing and Midwifery, Queen’s University Belfast, Belfast, UK

2. Centre for Public Health, Queen’s University Belfast, Belfast, UK

3. Research Department of Primary Care and Population Health, University College London, London, UK

4. Northern Ireland Clinical Trials Unit, Belfast, UK

5. MRC/CSO Social & Public Health Sciences Unit, University of Glasgow, Glasgow, UK

6. School of Social Sciences, Cardiff University, Cardiff, UK

7. Department of Social and Environmental Health Research, London School of Hygiene and Tropical Medicine, London, UK

8. School of Social Sciences, Education and Social Work, Queen’s University Belfast, Belfast, UK


Research Fellow(s) or PhD Student

Dr Susan Lagdon (Project Manager) & Dr Theresa McShane (Research Fellow)

Name & Institution of Collaborators

As above

Name of External Partner Organisations

Public Health Agency Northern Ireland, DHPSS, NI; Council for Curriculum Authority NI; Public Health Wales; NHS Scotland; Education Scotland; Sex Education Forum England;

Description of Project:

Aim; Methods; Expected Outcomes


Background: Teenage pregnancy remains a worldwide health concern, and is an outcome of, and contributor to, health inequalities. The need for gender-sensitive interventions targeted to males to address teenage pregnancy has been highlighted as a global health need by the World Health Organisation and identified in systematic reviews of relationship and sexuality education (RSE).


Aim: This study aims to test the effectiveness in reducing unprotected heterosexual teenage sex of an interactive film-based RSE intervention offered to males and females aged 14 years in schools which draws explicit attention to the role of males in preventing an unintended pregnancy.


Methods and analysis: A phase III effectiveness cluster randomised controlled trial with embedded process and economic evaluation. If I Were Jack encompasses a culturally sensitive interactive film, classroom materials, a teacher-trainer session, and parent animations and will be delivered in place of usual RSE. Control schools will not receive the intervention and will continue to deliver usual RSE. Participants will be unblinded to allocation due to the pragmatic nature of the setting. Schools are the unit of randomisation stratified per country and by socio-economic status, with 1:1 concealed allocation. We aim to recruit 66 UK schools (24 Northern Ireland; 14 England, Scotland, Wales) and 7904 pupils. A questionnaire will be administered at baseline and at 12-14 month follow-up. The primary outcome is a surrogate measure associated with unintended teenage pregnancy: had unprotected sex. Secondary outcomes include knowledge, attitudes, skills and intentions relating to avoiding teenage pregnancy in addition to frequency of engagement in sexual intercourse, contraception use, and diagnosis of sexually transmitted infections.

Ethics and dissemination Ethical approval was obtained from a Research Ethics Committee, Queen’s University Belfast. Results will be published in peer-reviewed journals and disseminated to stakeholders. Funding is from the National Institute for Health Research.

Trial registration ISRCTN: 99459996; Pre-results

Image(s) for Website:




Links/URLs to external pages, e.g., study webpage, reports, publications etc.

Any other relevant information

Lohan, M., Aventin, A., Clarke, M., Curran, R., Maguire, L., Hunter, R., ... O'Hare, L. (2018). JACK trial protocol: a phase III multicentre cluster randomised controlled trial of a school-based relationship and sexuality education intervention focusing on young male perspectives. BMJ Open, 8, [022128]. DOI:


Lohan, M., Aventin, A., Clarke, M., Curran, R., McDowell, C., Agus, A., ... Young, H. (2018). Can teenage men be targeted to prevent teenage pregnancy? A feasibility cluster randomised controlled intervention trial in schools. Prevention Science, 1-12. DOI: 10.1007/s11121-018-0928-z