JMIR Publications

ABSTRACT

Background:

Excessive screen time in early childhood is a global public health concern, yet fewer than one-third of young children meet recommended guidelines. Parental screen behavior is among the strongest modifiable determinants of child screen time, and parent-focused mobile health (mHealth) interventions are a promising but understudied approach. Whether app-recorded parenting behaviors relate to the magnitude of child screen time reduction has rarely been examined.

Objective:

This study examined whether the Watch Me app, an mHealth parent-training platform, was associated with a greater short-term reduction in child screen time over 7 days than an active comparison condition (psychoeducation plus diary-only self-monitoring). Exploratory analyses examined app-recorded parenting behaviors and day-level parent–child screen time associations.

Methods:

In this two-arm pilot randomized controlled trial, 61 community-recruited parent–child dyads (parents aged 28–47 years; children 3–7 years) were randomly allocated to an intervention group (Watch Me app) or a comparison group receiving psychoeducation plus diary-only app self-monitoring. The intervention was self-administered: after a single standardized onboarding session, no ongoing coaching or push reminders were provided, and parents completed in-app daily diary entries during the 7-day intervention period. The primary outcome was child screen time change (min/day), parent-reported via the in-app daily diary. Within-group change was assessed with the Wilcoxon signed-rank test and between-group differences with the Mann–Whitney U test and analysis of covariance (ANCOVA) adjusting for baseline child screen time (primary analysis). Exploratory Spearman correlations examined day-specific parent–child screen time associations across dyads and correlations between app-recorded parenting behaviors and child screen time change.

Results:

Of 61 allocated dyads, 55 provided sufficient post-intervention diary data for the complete-case analysis (intervention n=31, comparison n=24). After baseline adjustment, the intervention group showed a greater reduction in child screen time than the comparison group (ANCOVA β=21.31 min/day; 95% CI 6.45 to 36.17; P=.006; R²=.419). Within-group reduction was significant in the intervention group (−21.8 min/day; Wilcoxon r=.53, P=.003) but not the comparison group (P=.354). Exploratory analyses showed day-specific parent–child screen time associations across dyads on days 4 to 6 (peak day 5; Spearman ρ=.57, P=.001) and an association between greater narration-with-praise implementation and greater child screen time reduction (ρ=−.43, P=.039, n=23).

Conclusions:

In this pilot randomized controlled trial, the Watch Me app was associated with a greater short-term reduction in child screen time over 7 days than psychoeducation plus diary-only self-monitoring. Exploratory analyses identified day-level parent–child coupling and narration-with-praise implementation as candidate process variables rather than established mechanisms. These findings provide preliminary effect-size estimates and require confirmation in an adequately powered, prospectively specified study. Clinical Trial: UMIN Clinical Trials Registry UMIN000061851; https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000070769