TY  - JOUR
AU  - Bell, Imogen
AU  - Arnold, Chelsea
AU  - Gilbertson, Tamsyn
AU  - D’Alfonso, Simon
AU  - Castagnini, Emily
AU  - Chen, Nicola
AU  - Nicholas, Jennifer
AU  - O’Sullivan, Shaunagh
AU  - Valentine, Lee
AU  - Alvarez-Jimenez, Mario
PY  - 2023
DA  - 2023/12/13
TI  - A Personalized, Transdiagnostic Smartphone Intervention (Mello) Targeting Repetitive Negative Thinking in Young People With Depression and Anxiety: Pilot Randomized Controlled Trial
JO  - J Med Internet Res
SP  - e47860
VL  - 25
KW  - repetitive negative thinking
KW  - rumination
KW  - anxiety
KW  - depression
KW  - mobile app
KW  - just-in-time adaptive interventions
KW  - youth mental health
KW  - adolescent
KW  - mobile phone
AB  - Background: Repetitive negative thinking (RNT) is a key transdiagnostic mechanism underpinning depression and anxiety. Using “just-in-time adaptive interventions” via smartphones may disrupt RNT in real time, providing targeted and personalized intervention. Objective: This pilot randomized controlled trial evaluates the feasibility, acceptability, and preliminary clinical outcomes and mechanisms of Mello—a fully automated, personalized, transdiagnostic, and mechanistic smartphone intervention targeting RNT in young people with depression and anxiety. Methods: Participants with heightened depression, anxiety, and RNT were recruited via social media and randomized to receive Mello or a nonactive control over a 6-week intervention period. Assessments were completed via Zoom sessions at baseline and at 3 and 6 weeks after baseline. Results: The findings supported feasibility and acceptability, with high rates of recruitment (N=55), uptake (55/64, 86% of eligible participants), and retention (52/55, 95% at 6 weeks). Engagement was high, with 90% (26/29) and 59% (17/29) of the participants in the Mello condition still using the app during the third and sixth weeks, respectively. Greater reductions in depression (Cohen d=0.50), anxiety (Cohen d=0.61), and RNT (Cohen d=0.87) were observed for Mello users versus controls. Mediation analyses suggested that changes in depression and anxiety were accounted for by changes in RNT. Conclusions: The results indicate that mechanistic, targeted, and real-time technology-based solutions may provide scalable and effective interventions that advance the treatment of youth mental ill health. Trial Registration: Australian New Zealand Clinical Trials Registry ACTRN12621001701819; http://tinyurl.com/4d3jfj9f 
SN  - 1438-8871
UR  - https://www.jmir.org/2023/1/e47860
UR  - https://doi.org/10.2196/47860
UR  - http://www.ncbi.nlm.nih.gov/pubmed/38090786
DO  - 10.2196/47860
ID  - info:doi/10.2196/47860
ER  -