Effects of a Digital Mental Health Intervention on Perceived Stress and Rumination in Adolescents Aged 13 to 17 Years: Randomized Controlled Trial
Authors: Boucher Eliane M , Ward Haley , Miles Cynthia J , Henry Robert D , Stoeckl Sarah Elizabeth 
Published: February 2024

Background
Although adolescents report high levels of stress, they report engaging in few stress management techniques. Consequently, developing effective and targeted programs to help address this transdiagnostic risk factor in adolescence is particularly important. Most stress management programs for adolescents are delivered within schools, and the evidence for these programs is mixed, suggesting a need for alternative options for stress management among adolescents.

Objective
The aim of the study is to test the short-term effects of a self-guided digital mental health intervention (DMHI) designed for adolescents on perceived stress and rumination (ie, brooding).

Methods
This was a 12-week, 2-arm decentralized randomized controlled trial of adolescents aged 13 to 17 years who presented with elevated levels of perceived stress and brooding. Participants were randomly assigned to engage with a self-guided DMHI (Happify for Teens) or to a waitlist control. Participants assigned to the intervention group were given access to the program for 12 weeks. Happify for Teens consists of various evidence-based activities drawn from therapeutic modalities such as cognitive behavioral therapy, positive psychology, and mindfulness, which are then organized into several programs targeting specific areas of concern (eg, Stress Buster 101). Participants in the waitlist control received access to this product for 12 weeks upon completing the study. Participants in both groups completed measures of perceived stress, brooding, optimism, sleep disturbance, and loneliness at baseline, 4 weeks, 8 weeks, and 12 weeks. Changes in outcomes between the intervention and waitlist control groups were assessed using repeated-measures multilevel models.

Results
Of the 303 participants included in data analyses, 132 were assigned to the intervention and 171 to the waitlist. There were significantly greater improvements in the intervention condition for perceived stress (intervention: B=–1.50; 95% CI –1.82 to –1.19; P<.001 and control: B=–0.09; 95% CI –0.44 to 0.26; P=.61), brooding (intervention: B=–0.84; 95% CI –1.00 to –0.68; P<.001 and control: B=–0.30; 95% CI –0.47 to –0.12; P=.001), and loneliness (intervention: B=–0.96; 95% CI –1.2 to –0.73; P<.001 and control: B=–0.38; 95% CI: –0.64 to –0.12; P=.005) over the 12-week study period. Changes in optimism and sleep disturbance were not significantly different across groups (Ps≥.096).

Conclusions
Happify for Teens was effective at reducing perceived stress, rumination, and loneliness among adolescents over 12 weeks when compared to a waitlist control group. Our data reveal the potential benefits of DMHIs for adolescents, which may present a more scalable, destigmatized, and cost-effective alternative to school-based programs.

Trial Registration
ClinicalTrials.gov NCT04567888; https://clinicaltrials.gov/ct2/show/NCT04567888

International Registered Report Identifier (IRRID)
RR2-10.2196/25545