Promoting mental health using a mobile Health application in adolescents with a chronic somatic illness: A randomised waitlist controlled trial (preprint)

Abstract

Background: Over 17% of children in the Netherlands live with a chronic illness. They are at risk of developing mental health problems, affecting quality of life and health outcomes. This study evaluates a preventive, transdiagnostic mobile health intervention, the Grow It! app, aiming to enhance overall well-being by creating emotional insight and reflection, whilst encouraging the use of adaptive coping strategies.
Methods: Using a randomised waitlist controlled design, adolescents aged 10–18 years with a chronic somatic illness were recruited through a university medical hospital and randomised to a waitlist control group or an intervention group that used the Grow It! app. Follow-up assessments were conducted immediately after the four-week intervention period and three months later. After the final follow-up, the waitlist control group also used the Grow It! app and completed questionnaires immediately after and three months later. Primary outcome measures were symptoms of anxiety and depression. Data were analysed with linear mixed models on an intention-to-treat basis.
Findings: Between August 2021 and September 2023, 208 participants were enrolled (M_age=13.96, SD=2.20, 57.69% female), with 105 randomised to the Grow It! intervention group and 103 to the waitlist control group. At the overall group level, symptoms of anxiety (χ²(3, 497.01)=2.08, p=.1021) and depression (χ^²(3, 497.01)=0.71, p=.5459) remained stable over time, indicating no significant change across the full sample. However, among adolescents who used the Grow It! app, adolescents with elevated anxiety/depressive at baseline demonstrated the greatest benefit, showing larger symptom reductions than those who initially reported low symptom levels.
Interpretation: These findings suggest that the Grow It! app may offer meaningful benefits for adolescents with a chronic somatic illness experiencing elevated mood and anxiety symptoms, highlighting its potential value as a preventive and supportive tool in paediatric healthcare.
Funding: Sophia Foundation, NWA-ORC eHealth Junior consortium & PROTECt ME Convergence