Efficacy of smartphone-based behavioral activation, assertiveness training, and problem-solving therapy for parenting stress in parents raising autistic children: a multicenter, randomized, open-label, parallel-group trial

Parents of autistic children often experience high levels of stress and depressive symptoms. Although cognitive behavioral therapy (CBT) is effective in alleviating depression and reducing stress, its delivery requires trained personnel and considerable time, limiting accessibility. Smartphone applications may provide a feasible alternative. This study evaluated the efficacy of smartphone-delivered behavioral activation, assertiveness training, and problem-solving therapy in improving depressive symptoms and reducing stress among parents of autistic children. This was an individually randomized, parallel-group, multicenter trial. Eligible participants were parents aged 24 to < 60 years caring for biological children aged 6 to < 16 years diagnosed with autism by child psychiatrists. Participants were randomly assigned (1:1) to a smartphone-based intervention or a control group that received psychoeducation only. Both groups continued treatment as usual. The intervention consisted of an 8-week smartphone application program delivering behavioral activation, assertiveness training, and problem-solving therapy. The primary endpoint was the Patient Health Questionnaire-9 (PHQ-9) score at Week 8. Secondary outcomes included Generalized Anxiety Disorder-7 (GAD-7) scores at Weeks 4 and 8, Cognitive Behavioral Therapy Skills Scale scores, presenteeism assessed with the Health and Work Performance Questionnaire (HPQ) at Week 8, and app usage. A total of 63 parents were randomized to the intervention group (n = 31) or control group (n = 32). Changes in PHQ-9 scores from baseline to Week 8 did not differ significantly between groups. No significant between-group differences were observed for GAD-7, CBT Skills, or HPQ presenteeism at Week 8. The smartphone-based intervention did not demonstrate additional benefits over psychoeducation alone in reducing depressive symptoms. Although symptoms improved in both groups, no significant between-group differences were observed, and the findings should be interpreted cautiously given the limited statistical power. This study was retrospectively registered in UMINCTR (ID UMIN000052319) on October 1, 2023.