Supplementary Material for: Effectiveness of an Internet-Based Self-Help Intervention versus Public Mental Health Advice to Reduce Worry during the COVID-19 Pandemic: A Pragmatic, Parallel-Group, Randomized Controlled Trial

Introduction: The mental health burden for the general population due to the COVID-19 pandemic has been highlighted. Evidence on effective, easily accessible public health interventions to reduce worry, a major transdiagnostic risk-factor for, e.g., anxiety and depression, is scarce. Objective: In a pragmatic randomized controlled trial, we aimed to assess whether an internet cognitive-behavioral self-help intervention could reduce worry more than public mental health advice in the general population. Methods: Eligible internet users above the age of 18 were recruited from the German general population and randomly assigned, to either get.calm-move.on (GCMO), a 10-day unguided, internet-based self-help intervention, or mental health advice waiting group (MHA-W, receiving officially endorsed mental health recommendations). The primary outcome was level of worry, using the Penn State Worry Questionnaire (PSWQ), 2 weeks after randomization. Baseline assessment and 2-month and 6-month follow-ups were conducted. The trial was registered at the German Clinical Trials Registry (DRKS00021153). Results: Between April 7, 2020 and December 11, 2020, we randomly assigned 351 individuals to receive either GCMO (n = 175) or MHA-W (n = 176). Participants receiving GCMO (PSWQ = 46.6; change –10.3) reported significantly less worrying at post-intervention (F1,219 = 12.9; p d = 0.38) than MHA-W controls (PSWQ = 51.6; change –5.1). Improvements were also seen on most secondary outcomes, including symptoms of anxiety and depression, general well-being, resiliency, and emotion regulation skills. Improvements made from baseline were stable until the 6-month follow-up. Conclusions: This internet-based self-help intervention providing cognitive-behavioral techniques to cope with the threatening pandemic situation is effective in reducing worry in the general population and should complement existing and potentially effective mental health recommendations.引言：新冠疫情给普通人群带来的精神健康负担已受到广泛关注。目前针对可有效缓解过度担忧——焦虑、抑郁等多种精神障碍的跨诊断风险因素——且易于获取的公共卫生干预措施的相关证据仍较为匮乏。 研究目的：本项务实型随机对照试验旨在评估，一款互联网认知行为自助干预（internet cognitive-behavioral self-help intervention）是否比公共精神健康指导方案更能有效降低普通人群的过度担忧水平。 研究方法：本研究从德国普通人群中招募符合入组条件的18岁以上互联网用户，将其随机分配至两个组别：其一为get.calm-move.on（GCMO），即一款为期10天的非指导式互联网自助干预项目；其二为精神健康指导等候组（MHA-W），受试者将获取官方认可的精神健康推荐方案。本研究的主要结局指标为随机分组2周后采用宾夕法尼亚洲担忧问卷（Penn State Worry Questionnaire, PSWQ）评估的担忧水平。此外，还开展了基线评估以及随访2个月、6个月的追踪测评。本试验已在德国临床试验注册平台（German Clinical Trials Registry, DRKS00021153）完成注册。 研究结果：2020年4月7日至2020年12月11日期间，本研究共随机纳入351名受试者，其中GCMO组175例，MHA-W组176例。干预后评估显示，GCMO组受试者的担忧水平（宾夕法尼亚洲担忧问卷得分46.6分，较基线变化量为-10.3）显著低于MHA-W对照组（得分51.6分，较基线变化量为-5.1；F(1,219)=12.9；效应量d=0.38）。此外，多数次要结局指标也呈现出显著改善，包括焦虑与抑郁症状、总体幸福感、心理弹性以及情绪调节能力。从基线至6个月随访期，受试者的症状改善效果始终保持稳定。 研究结论：这款基于互联网的、提供认知行为应对技巧以应对疫情威胁性情境的自助干预项目，可有效降低普通人群的过度担忧水平，可作为现有精神健康推荐方案的有效补充。