Just-in-Time Delivery of Cognitive Behavioral Therapy-Based Exercises: Single-Case Experimental Design With Random...

Area of Science:

• Digital Health
• Mental Health Technology
• Behavioral Science

Background:

• Just-in-time adaptive interventions (JITAIs) offer scalable and precise mental health support through automated, remote delivery.
• Smartphone apps can assess user psychological states and prompt timely behavioral engagement.
• JITAIs hold promise for precision health, but empirical evidence remains limited.

Purpose of the Study:

• To implement and evaluate a smartphone-based JITAI for daily stress management using cognitive behavioral therapy (CBT).
• To assess the feasibility and efficacy of the JITAI using a single-case experimental design.

Main Methods:

• Recruited 8 Japanese adults for a 28-day study with an AB phase design and multiple random baselines.
• Participants reported stress levels thrice daily via smartphone.
• A CBT-based intervention with 6 exercises was offered based on reported stress levels during the intervention phase.

Main Results:

• Approximately 70% of participants found the intervention useful.
• A statistically significant decrease in reported stress levels was observed post-intervention (P=.005).
• Significant acute reductions in momentary stress (Cohen dz=0.58) and depressive rumination (Cohen dz=1.17) were detected.

Conclusions:

• The mobile JITAI intervention was feasible and effective in reducing stress and rumination in the study sample.
• Limitations include a small, non-clinical sample, potentially limiting generalizability.
• Further research is needed to solidify conclusions on technical, technological, and clinical aspects of mobile mental health interventions.