BackgroundThe transition to adulthood is a unique developmental period characterized by numerous personal and social role changes and increased opportunities for alcohol consumption. Using alcohol to cope with anxiety symptoms is commonly reported, and young people with anxiety are at a greater risk of hazardous alcohol use and progression to alcohol use disorder. Anxiety and alcohol use tend to fuel each other in an exacerbating feed-forward cycle, leading to difficult-to-treat chronic problems. The peak in onset of anxiety and alcohol disorders suggests this developmental window represents a promising opportunity for early intervention before these problems become entrenched.ObjectiveThis study aims to evaluate the efficacy of the Inroads program, a therapist-supported, internet-delivered early intervention for young adults that targets alcohol use, anxiety symptoms, and the interconnections between these problems.MethodsA randomized controlled trial will be conducted nationally among young Australians (aged 17-24 years) who experience anxiety symptoms and drink alcohol at hazardous or harmful levels. Participants will be individually randomized on a 1:1 basis to receive the Inroads intervention or assessment plus alcohol guidelines. Participants randomized to the Inroads intervention will receive access to 5 Web-based cognitive behavioral therapy (CBT) modules and weekly therapist support via email and/or phone. The primary outcome assessment will be 8 weeks post baseline, with follow-up assessment 6 months post baseline to determine the sustainability of the intervention effects. Primary outcomes will be the total number of standard drinks consumed in the past month (assessed by the Timeline Follow-Back procedure), severity of alcohol-related harms (assessed by the Brief Young Adult Alcohol Consequences Questionnaire), and anxiety symptoms across multiple disorders (assessed by the Generalized Anxiety Disorder-7). Secondary outcomes will include alcohol outcome expectancies; functional impairment and quality of life; and symptoms of social anxiety, anxious arousal, and depression. Results will be analyzed by intention-to-treat using multilevel mixed effects analysis for repeated measures.ResultsThe study is funded from 2017 to 2020 by Australian Rotary Health. Recruitment is expected to be complete by late-2018, with the 6-month follow-ups to be completed by mid-2019. Results are expected to be published in 2020.ConclusionsThe study will be the first to evaluate the benefits of a youth-focused early intervention that simultaneously targets anxiety and hazardous alcohol use. By explicitly addressing the interconnections between anxiety and alcohol use and enhancing CBT coping skills, the Inroads program has the potential to interrupt the trajectory toward co-occurring anxiety and alcohol use disorders. The Web-based format of the program combined with minimal therapist support means that if effective, the program could be widely disseminated to reach young people who are not currently able or willing to access face-to-face treatment.Trial RegistrationAustralian New Zealand Clinical Trials Registry ACTRN12617001609347; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372748&isReview=true (Archived by WebCite at http://www.webcitation.org/77Au19jmf)International Registered Report Identifier (IRRID)DERR1-10.2196/12370