Objective To quantify the effects of a series of text messages (safetxt) delivered in the community on incidence of chlamydia and gonorrhoea reinfection at one year in people aged 16-24 years. Design Parallel group randomised controlled trial. Setting 92 sexual health clinics in the United Kingdom. Participants People aged 16-24 years with a diagnosis of, or treatment for, chlamydia, gonorrhoea, or non-specific urethritis in the past two weeks who owned a mobile phone. Interventions 3123 participants assigned to the safetxt intervention received a series of text messages to improve sex behaviours: four texts daily for days 1-3, one or two daily for days 4-28, two or three weekly for month 2, and 2-5 monthly for months 3-12. 3125 control participants received a monthly text message for one year asking for any change to postal or email address. It was hypothesised that safetxt would reduce the risk of chlamydia and gonorrhoea reinfection at one year by improving three key safer sex behaviours: partner notification at one month, condom use, and sexually transmitted infection testing before unprotected sex with a new partner. Care providers and outcome assessors were blind to allocation. Main outcome measures The primary outcome was the cumulative incidence of chlamydia or gonorrhoea reinfection at one year, assessed by nucleic acid amplification tests. Safety outcomes were self-reported road traffic incidents and partner violence. All analyses were by intention to treat. Results 6248 of 20 476 people assessed for eligibility between 1 April 2016 and 23 November 2018 were randomised. Primary outcome data were available for 4675/6248 (74.8%). At one year, the cumulative incidence of chlamydia or gonorrhoea reinfection was 22.2% (693/3123) in the safetxt arm versus 20.3% (633/3125) in the control arm (odds ratio 1.13, 95% confidence interval 0.98 to 1.31). The number needed to harm was 64 (95% confidence interval number needed to benefit 334 to ∞ to number needed to harm 24) The risk of road traffic incidents and partner violence was similar between the groups. Conclusions The safetxt intervention did not reduce chlamydia and gonorrhoea reinfections at one year in people aged 16-24 years. More reinfections occurred in the safetxt group. The results highlight the need for rigorous evaluation of health communication interventions. Trial registration ISRCTN registry [ISRCTN64390461][1]. After publication of the primary and secondary analyses detailed in the statistical analysis plan, individual deidentified patient data, including a data dictionary, will be made available via our data sharing portal FreeBIRD website indefinitely. The trial protocol, statistical analysis plan, and trial publications will be freely available online. [1]: /external-ref?link_type=ISRCTN&access_num=ISRCTN64390461

中文翻译：

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通过短信 (safetxt) 提供的行为干预对 16-24 岁人群性传播再感染的有效性：随机对照试验


目的 量化社区中发送的一系列短信 (safetxt) 对 16-24 岁人群一年内衣原体和淋病再感染发生率的影响。设计平行组随机对照试验。在英国设立92个性健康诊所。参与者 年龄在 16-24 岁之间、在过去两周内诊断出衣原体、淋病或非特异性尿道炎或接受过治疗、拥有手机的人士。干预措施 分配到 safetxt 干预措施的 3123 名参与者收到了一系列改善性行为的短信：第 1-3 天每天 4 条短信，第 4-28 天每天 1 到 2 条，第 2 个月每周 2 到 3 条，第 2 到 5 个月每周 2 到 3 条。第 3-12 个月每月一次。 3125 名对照参与者在一年内每月收到一条短信，要求更改邮政或电子邮件地址。据推测，safetxt 将通过改善三个关键的安全性行为来降低一年后衣原体和淋病再次感染的风险：一个月时通知伴侣、使用安全套以及在与新伴侣发生无保护性行为之前进行性传播感染检测。护理提供者和结果评估者对分配视而不见。主要结果指标 主要结果是一年内衣原体或淋病再感染的累积发生率，通过核酸扩增测试进行评估。安全结果是自我报告的道路交通事故和伴侣暴力。所有分析均按意向治疗进行。结果 2016年4月1日至2018年11月23日期间，对20476名接受资格评估的人中的6248人进行了随机分组。 4675/6248 例 (74.8%) 的主要结果数据可用。一年时，safetxt 组中衣原体或淋病再感染的累积发生率为 22.2% (693/3123)，而安全组为 20%。对照组为 3% (633/3125)（优势比 1.13，95% 置信区间 0.98 至 1.31）。造成伤害所需的人数为 64（受益所需的 95% 置信区间数为 334 到造成伤害所需的人数 24）。各组之间道路交通事故和伴侣暴力的风险相似。结论 safetxt 干预措施并未减少 16-24 岁人群一年内衣原体和淋病的再感染。 safetxt 组中发生了更多的再感染。结果凸显了对健康传播干预措施进行严格评估的必要性。试用注册 ISRCTN 注册表 [ISRCTN64390461][1]。在统计分析计划中详细介绍的主要和次要分析发布后，将通过我们的数据共享门户 FreeBIRD 网站无限期地提供个人身份识别的患者数据，包括数据字典。试验方案、统计分析计划和试验出版物将在网上免费提供。 [1]：/外部引用？link_type=ISRCTN&access_num=ISRCTN64390461