A Systematic Review of the Effectiveness, Content, and Usage Patterns of Mobile Mental Health Interventions on Smartphone Platforms for Anxiety Symptoms

"This systematic review aims to examine the content, usage pattern and efficacy of mobile mental health interventions in reducing anxiety symptoms. A search of 10 electronic databases returned 44 408 studies in total and 27 studies met the inclusion criteria, including 4460 participants in total. The rate of attrition was 27% (SD = 22) among the participants who initiated the app use. The rate of significant reductions in measures of anxiety symptoms was 87% from within-subjects pretest to posttest assessments, yet this rate dropped to 46% when compared to a waitlist/control group. A vast majority of the studies used cognitive and/or behavioral interventions (N = 26, 96%), a few studies included professional support (N = 11, 41%), a structured form of delivering the interventions (N = 8, 30%) or tailored it to users’ needs (N = 6, 22%). Few studies reported the actual time spent on the app per week (N = 4, M = 63.76, SD = 62.17). The mobile mental health interventions were effective in reducing anxiety symptoms, yet this effectiveness eroded compared to control groups. There is a need to develop consistent ways of reporting the usage patterns and testing evidence-based interventions other than cognitive behavioral treatments."