Abstract
INTRODUCTION: Youth suicidal ideation and behaviour is concerning due to its widespread prevalence, morbidity and potentially fatal consequences. Digital mental health interventions have been found to improve access to low-cost and high-quality support for a range of mental health issues, yet there are few digital interventions available for suicide prevention in young people. In addition, no studies have examined how digital engagement strategies may impact the engagement and efficacy of digital interventions in suicide prevention. The current protocol describes a three-arm parallel randomised controlled trial. A therapeutic smartphone application ('LifeBuoy'; intervention condition) will be tested against a condition that consists of the LifeBuoy application plus access to a digital engagement strategy ('LifeBuoy+engagement'; intervention condition) to determine whether the addition of the digital strategy improves app engagement metrics. To establish the efficacy of the LifeBuoy application, both of these intervention conditions will be tested against an attention-matched control condition (a placebo app). METHODS AND ANALYSIS: 669 young Australians aged 17-24 years who have experienced suicidal ideation in the past 30 days will be recruited by Facebook advertisement. The primary outcomes will be suicidal ideation severity and level of app engagement. Primary analyses will use an intention-to-treat approach and compare changes from baseline to 30-day, 60-day and 120-day follow-up time points relative to the control group using mixed-effect modelling. A subset of participants in the intervention groups will be interviewed on their experience with the app and engagement strategy. Qualitative data will be analysed using an inductive approach, independent of a theoretical confirmative method to identify the group themes. ETHICS AND DISSEMINATION: The study has been approved by the University of New South Wales Human Research Ethics Committee (HC210400). The results of the trial will be disseminated via peer-reviewed publications in scientific journals and conferences. TRIAL REGISTRATION NUMBER: ACTRN12621001247864.