Autonomous Motivation Trajectory Following Adoption of a Team-Based Gamification App Among Adults With Diabetes:...

Autonomous motivation, grounded in self-determination theory, is important for sustaining diabetes self-care behaviors. Although mobile health interventions, gamification, and peer support are increasingly used to enhance motivation in diabetes care, evidence on how motivation evolves over time remains limited. Specifically, it is unclear whether motivational change follows a linear pattern or a nonlinear trajectory, such as an initial increase followed by a subsequent decline. Clarifying these temporal patterns is critical for informing the design of adaptive diabetes self-care interventions.

The objective of this study was to characterize the 1-year developmental trajectory of autonomous motivation following the real-world introduction of a commercially available team-based gamification app.

This prospective, single-arm longitudinal study involved adults with diabetes (predominantly type 2) recruited from outpatient clinics in Japan. Participants were instructed to use a team-based gamification app designed to promote desirable habits through peer support and social comparison for at least 7 days. The primary outcome, autonomous motivation, was assessed using the Treatment Self-Regulation Questionnaire-Autonomous Motivation subscale (TSRQ-AM; score range 7-49) at baseline, 6 weeks, 6 months, and 1 year. Secondary measures included hemoglobin A_1c (HbA_1c), body weight, triglycerides, and psychological scales (eg, Self-Efficacy Scale for Diabetes Self-Care, Summary of Diabetes Self-Care Activities, Problem Areas in Diabetes scale, and World Health Organization-Five Well-Being Index). To analyze the trajectory, we used linear mixed-effects models with random intercepts for participants. The final model included fixed effects for time (as both linear and quadratic terms), age, sex, employment status, family structure, baseline BMI, and baseline HbA_1c.

Of 32 consenting participants, 29 (90.6%) were included in the primary analysis; clinical data at 1 year were available for 26 (81.3%) participants. In exploratory analyses, mean TSRQ-AM scores increased from baseline (37.4, SD 7.9) to 6 months (39.5, SD 7.4; Cohen d=0.47). Over the 1-year period, body weight decreased significantly (b=-0.39; P=.01), whereas HbA_1c (P=.40) and triglycerides (P=.14) showed no significant changes. The TSRQ-AM score showed a significant nonlinear change over time. A model including a quadratic time term fit significantly better than a linear-only model (χ²₁=4.1; P=.04), with a significant quadratic effect (b=-7.26; P=.045), indicating an inverted U-shaped trajectory peaking at 6 months. Higher baseline BMI was associated with lower TSRQ-AM scores (b=-1.00; P=.001).

This formative study provides preliminary evidence of a nonlinear, 1-year trajectory of autonomous motivation following the introduction of a team-based app. The observed curvilinear pattern suggests that autonomous motivation during the intervention may peak at around 6 months, underscoring the importance of adaptive intervention designs to maintain engagement over time. The accompanying reduction in body weight suggests potential physiological relevance that warrants further investigation in controlled studies.

UMIN Clinical Trials Registry UMIN000044874; https://tinyurl.com/59bzb68k.