Ona McCarthy


Research Fellow


Keppel Street
United Kingdom

+44 (0)20 7927 2581

I am an epidemiologist in the Department of Population Health. I completed my BA at the University of Massachusetts (2001) where I studied Sociology and Psychology and MSc in Epidemiology at LSHTM (2005). I joined LSHTM in March of 2013.


Faculty of Epidemiology and Population Health
Department of Population Health


Maternal, Adolescent, Reproductive & Child Health (MARCH)


I teach on the Basic Epidemiology and Design & Analysis of Epidemiological Studies MSc modules and on the Introductory Course in Epidemiology and Medical Statistics and Adolescent Health in Low and Middle Income Countries short courses. I am a personal tutor on the Reproductive and Sexual Health Research MSc.


My research interests include developing and evaluating interventions to improve sexual and reproductive health.

Research Area
Complex interventions
Public health
Sexual health
Adolescent health
Behaviour change
Mixed methods
Randomised controlled trials
Reproductive health
Disease and Health Conditions
Sexually transmitted infection
United Kingdom
Arab World
Europe & Central Asia (developing only)
Euro area
Latin America & Caribbean (developing only)

Selected Publications

Simple steps to develop trial follow-up procedures.
McCarthy, O. ; French, R.S. ; Roberts, I. ; Free, C. ;
Young People's Views and Experiences of a Mobile Phone Texting Intervention to Promote Safer Sex Behavior.
French, R.S. ; McCarthy, O. ; Baraitser, P. ; Wellings, K. ; Bailey, J.V. ; Free, C. ;
JMIR Mhealth Uhealth
Can text messages increase safer sex behaviours in young people? Intervention development and pilot randomised controlled trial.
Free, C. ; McCarthy, O. ; French, R.S. ; 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
Safetxt: a pilot randomised controlled trial of an intervention delivered by mobile phone to increase safer sex behaviours in young people.
McCarthy, O.L. ; French, R.S. ; Baraitser, P. ; Roberts, I. ; Rathod, S.D. ; Devries, K. ; Bailey, J.V. ; Edwards, P. ; Wellings, K. ; Michie, S. ; Free, C. ;
BMJ Open
Effect of a mobile phone-based intervention on post-abortion contraception: a randomized controlled trial in Cambodia.
Smith, C. ; Ngo, T.D. ; Gold, J. ; Edwards, P. ; Vannak, U. ; Sokhey, L. ; Machiyama, K. ; Slaymaker, E. ; Warnock, R. ; McCarthy, O. ; Free, C. ;
Bull World Health Organ
The Sexunzipped trial: optimizing the design of online randomized controlled trials.
Bailey, J.V. ; Pavlou, M. ; Copas, A. ; McCarthy, O. ; Carswell, K. ; Rait, G. ; Hart, G. ; Nazareth, I. ; Free, C. ; French, R. ; Murray, E. ;
J Med Internet Res
What young people want from a sexual health website: design and development of sexunzipped.
McCarthy, O. ; Carswell, K. ; Murray, E. ; Free, C. ; Stevenson, F. ; Bailey, J.V. ;
J Med Internet Res
See all Ona McCarthy's Publications