Safetxt: A randomised controlled trial of an intervention delivered by mobile phone messaging to reduce sexually transmitted infections (STI) by increasing sexual health precaution behaviours in young people

Objective: To establish the effectiveness of a safer sex intervention delivered by mobile phone messaging on STI infection at one year. To establish the effect of the intervention on partner notification, condom use and STI testing at one month & one year. To explore which components of the intervention are effective. To establish the costs and cost-effectiveness of the intervention. Design: A randomised controlled trial. Setting: The intervention is delivered by mobile phone messaging to participants in the community. Participants are recruited from services testing for STI across the UK. Strategy for reviewing the literature: We searched MEDLINE, EMBASE, Global health, Web of Science, PsycINFO and the Cochrane library. (Jan 1990- Nov 2014) to identify trials of mobile phone based support to increase safer sex behaviours and reduce STI. Target population: People aged 16-24 diagnosed with gonorrhoea, chlamydia or non-specific urethritis (NSU) in the last month. Recruitment and randomisation procedures: We will provide trial information, confirm eligibility and obtain consent by post, email or on the trial website. The researcher or participant will enter base-line data. A web-based link to an independent randomisation service will allocate the participants to receive the safer sex intervention or to a control group (see trial flow chart). The system will automatically generate text messages according to the allocation. Intervention: A safer sex intervention designed to reduce STIs by increasing correct treatment of STI, partner notification, condom use and STI testing before unprotected sex with a new partner. The intervention is delivered over 12 months from an automated IT system based at the trial co-ordinating centre. Comparator: A monthly text message checking contact details. Measurement of costs and outcome: The primary outcome at one year is chlamydia or gonorrhoea infection using NAAT tests. Secondary outcomes at one month & one year: safer sex behaviours (partner notification, condom use and testing for STI before unprotected sex with a new partner) and the theoretical constructs linked to the effects of intervention components (behaviour change techniques). We will collect one year data on STI infection by postal testing/ clinic data. We will collect self-reported data by post, text message, email or phone and partner attendance for treatment by clinic data. Costs of intervention delivery will be collected for economic modelling. Project timetable: Months 1-4 Trial set up Months 5-37 Recruitment Months 6-50 Follow up Months 51-54 Data analysis & writing up Sample size: Because the intervention can be delivered to large numbers of people at low cost, even a modest reduction in STI would deliver public health benefit. The trial has been designed to detect a reduction in incidence of STI of 3.4%. If the real difference in STI at 12 months is 17% vs 13.6% (RR 0.8) then there is a 90% chance that a trial with 6250 patients would achieve p = 0.05, even allowing for 20% loss to follow up. Expertise in the team: Members have strong expertise in sexual health, behaviour change, health promotion, mobile phone based interventions, sexual diversity and equality, conducting large randomised controlled trials, systematic reviews, health economics, statistics and epidemiology.