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The Intervention Design and Evaluation Group (IDEG)

Our vision is to be a world-leading centre of excellence for the development and evaluation of novel interventions to improve health and primary health care provision. We have a major focus on interventions to improve sexual and reproductive health. Disparities in health exist within and between countries. To promote equity in health and health care, our interventions are designed with input from users, specifically involving those at greatest need in the development process to ensure that interventions are accessible and relevant to them. We generate high quality evidence regarding the effectiveness and impact of interventions. We work in collaboration with service providers and policy makers to facilitate the implementation of effective interventions.

We conduct high quality research using mixed methods and inter-disciplinary approaches to understand health problems and health care use, generate and evaluate novel solutions, promote evidence informed implementation and make significant impacts on policy. We conduct randomised controlled trials to establish the effectiveness of interventions and mixed methods to explore the impact of interventions when implemented. We use established methods for designing health interventions working closely with users and drawing on relevant medical, psychological, social and educational knowledge and theory.

For further details of our approach please see our publications and projects.

Profiles List
Dr Sima Berendes


Research Fellow - Senior Trial Manager

Zahra Jamal

Trial Manager
IDEG Research2 columns
IDEG Research

The Safetxt trial is a randomised controlled trial funded by the NIHR Public Health Research led by Prof Cari Free. We developed the intervention with young people. The trial is designed to establish the effects of a safer sex mobile phone messaging intervention on STI infection at 12 months, among 6250 participant aged 16-24 in the UK. The trial fully recruited on time in Nov 2018 and is due to report during 2020.

Systematic reviews of randomised controlled trials of targeted client communication delivered by mobile phone for reproductive, maternal, newborn, child and adolescent health (RMNCAH). The work is a collaboration between Melissa Palmer and Cari Free at LSHTM, WHO, the Cochrane response team and the Cochrane Effective Practice and Organisation of Care Group. WHO funded the research, which is directly informing WHO guidance. Due to report in 2019.

Evaluating online Sexual and Reproductive Health Services: This is a collaboration between LSHTM and Kings College London funded by the Guys and St Thomas’ Charitable Trust via a grant to SH24. The work is jointly supervised by Prof Cari Free (LSHTM) and Dr Paula Baraitser (KCL) with PhD students based at LSHTM (Emma Wilson) and KCL (Sharmani Barnard and Emma Rezel). The work includes a randomised controlled trial evaluating the effect of promoting and offering online STI testing in the UK led by Emma Wilson. Additional studies are evaluating access among at risk groups; factors associated with use of online services and the implementation of online STI testing and oral contraception provision.

We are collaborating with Dr Chris Smith (Associate Professor, LSHTM and Nagasaki University), Elisa Oreglia (Lecturer in Global Digital Cultures, KCL) and Justin Watkins (Professor of South East Asian Languages, PSOAS) on an Arts and Humanities funded research project exploring womens’ contraception decisions and ways of seeking information. The project will lead to the development of an intervention to support reproductive health of women after medical abortion in Cambodia.

We are collaborating with Stirling University, Dundee University and Glasgow University on a project led by Queens University Belfast (Dr Michelle Mckinley): A NIHR HTA funded project for the development and pilot trial of a weight management intervention for pregnant women delivered by mobile phone.

Ona McCarthy, in collaboration with the Tajik Family Planning Association, the Palestinian Family Planning and Protection Association and the Organisation Centro de Investigación, Educación y Servicios, led the design and evaluation of interventions delivered by mobile phone to increase the acceptability of contraception among young people in Tajikistan, Bolivia and Palestine. The International Planned Parenthood Federation funded the work.

Systematic reviews of interventions delivered by mobile phone for the prevention of non-communicable disease: We have completed systematic reviews including 75 trials of interventions delivered by mobile phone targeting diet and physical activity, smoking cessation, alcohol reduction and medication adherence to prevent non-communicable disease.

Implementation & impact on policy
IDEG 2 columns Implementation & impact on policy
IDEG 2 columns Implementation & impact on policy

Smoking cessation support services delivered by text message

The txt2stop trial, was a single blind randomised controlled trial evaluating the effect of smoking cessation support delivered by text message on biochemically verified continuous abstinence at six months led by LSHTM in collaboration with the University of Auckland. Biochemically verified continuous abstinence at six months was significantly increased in the txt2stop group, with txt2stop proving successful in 10.7% of cases versus 4.9% in the control group.

The research directly resulted in a new smoking cessation support service in England delivered by text message. Following the publication of the paper in The Lancet in 2011, we worked with the Tobacco Control Marketing Team for the Department of Health (DH) in England to develop a new text messaging service. The service was made available free at the point of delivery from the NHS Stop Smoking website in January 2012. The evaluation demonstrated that quit rates in the service were similar or higher than those achieved in the txt2stop trial. The DH Senior Campaigns Manager states that the service 'continues to be a great success'. The service is available via the NHS smoke free website. Since 2012, between 63,000 and 90,000 people in England have used the service each year.

The World Health Organisation (WHO) and the International Telecommunications Union (ITU) have formed a partnership called the 'Be He@lthy, Be Mobile' initiative, which is supporting the implementation of SMS based smoking cessation support internationally. We are members of the informal WHO m-cessation group which developed the WHO and ITU publication 'A handbook on how to implement mTobaccoCessation'. In 2016, India launched a national smoking cessation support service delivered by text message and over 2 million people used the services in 2016. Costa Rica and the Philippines have developed similar programmes and Vietnam, Mongolia and Tunisia have started service development. Over 63 countries have expressed interest to WHO to roll out national services.

Informing policy on home use of misoprostol for medical abortion

Following publication of our systematic review, the WHO altered their guidance regarding home use of misoprostol following provision of mifepristone at the health-care facility and cite our review in 'WHO. Safe abortion: technical and policy guidance for health care systems 2011 p 65'. The RCOG Evidence based Clinical Guideline No 7 Nov 2011 'The Care of Women Requesting Induced Abortion' also cites our review.

Scientific Papers
Publications List
The effectiveness of smoking cessation, physical activity/diet and alcohol reduction interventions delivered by mobile phones for the prevention of non-communicable diseases: a systematic review of randomised controlled trials
Palmer M, Sutherland J, Barnard S, Wynne A, Rezel E, Doel A, Grigsby-Duffy L, Edwards S, Russell S, Hotopf E, Perel P, Free C
Plos One. January 5, 2018
A randomised controlled trial of an intervention delivered by app instant messaging to increase the acceptability of effective contraception among young people in Tajikistan
McCarthy OL, Ahamed I, Kulaeva F, Saibov S, Vandewiele M, Standaert S, Tokhirov R, Leurent B, Edwards P, Ahamed, Free C.
Reproductive Health. 2018;X(X); doi: Reproductive Health (2018) 15:28.
Development of an intervention delivered by mobile phone aimed at decreasing unintended pregnancy among young in three lower middle income countries
McCarthy OL, Wazwaz O, Osorio Calder V, Jado I, Saibov S, Stavridis A, López Gallardo J, Tokhirov R, Adada S, Huaynoca S, Makleff S, Vandewiele M, Standaert S, Free C.
BMC Public Health (2018) 18:576; doi:
An Intervention Delivered by App Instant Messaging to Increase Acceptability and Use of Effective Contraception Among Young Women in Bolivia: Protocol of a Randomized Controlled Trial
McCarthy OL, Osorio Calderon V, Makleff S, Huaynoca S, Leurent B, Edwards P, Lopez Gallardo J, Free C.
JMIR Res Protoc 2017;6(12):e252. URL: DOI: 10.2196/resprot.8679. PMID: 29254910. PMCID: 5748473
An intervention delivered by text message to increase the acceptability of effective contraception among young women in Palestine: study protocol for a randomised controlled trial
McCarthy OL, Wazwaz O, Jado I, Leurent B, Edwards P, Adada S, Stavridis A, Free Caroline
Trials. 2017;18(1):454. doi 10.1186/s13063-017-2191-1
Safetxt: a pilot randomised controlled trial of an intervention delivered by mobile phone to increase safer sex behaviours in young people
McCarthy OL, French RS, Baraitser P, Roberts I, Rathod SD, Devries K, Bailey JV, Edwards P, Wellings K, Michie S, Free C.
BMJ Open. 2016;6(12). doi: 10.1136/bmjopen-2016-013045
Can text messages increase safer sex behaviours in young people? Intervention development and pilot randomised controlled trial
Free C, McCarthy O, French RS, Wellings K, Michie S, Roberts I, Devries K, Rathod S, Bailey J, Syred J, Edwards P, Hart G, Palmer M, Baraitser P.
Health Technol Assess. 2016 Jul;20(57):1-82. doi: 10.3310/hta20570
Simple steps to develop trial follow-up procedures
McCarthy O, French R, Roberts I, Free C.
Trials. 2016 Jan 15;17:28. doi: 10.1186/s13063-016-1155-1.
Young people’s views and experiences of a mobile phone texting intervention to promote safer sex behaviour
French R, McCarthy O, Baraitser P, Wellings K, Bailey JV, Free C.
JMIR Mhealth Uhealth. 2016 Apr 15;4(2):e26. doi: 10.2196/mhealth.4302
Effect of a mobile phone-based intervention on post-abortion contraception: a randomized controlled trial in Cambodia
Smith C, Ngo TD, Gold J, Edwards P, Vannak U, Sokhey L, Machiyama K, Slaymaker E, Warnock R, McCarthy O, Free C.
Bull World Health Organ. 2015 Dec 1;93(12):842-50A. doi: 10.2471/BLT.15.160267. Epub 2015 Oct 15
Updates List Block
Updates List
New IDEG website

IDEG group is lauching its new website