JMIR Publications

ABSTRACT

Background:

Digital media technology has made screen time more available across multiple contexts, but our understanding of the unique ways children and families use digital media has lagged behind the rapid adoption of this technology.

Objective:

The purpose of this study was to evaluate the feasibility of an intensive longitudinal data collection protocol to objectively measure digital media use, physical activity, sleep, sedentary behavior, and social/emotional context among caregiver-child dyads. This paper also describes the preliminary convergent validity of Ecological Momentary Assessment (EMA) measures and describes preliminary agreement between caregiver self-reported mobile phone use and mobile phone use collected from passive mobile sensing.

Methods:

Caregiver-child dyads were recruited to complete a 30-day protocol. Within the 30-day period caregivers completed 7 days of EMA to measure child behavior problems and caregiver stress. Caregivers and children wore an Axivity AX3 accelerometer to assess physical activity, sedentary behavior, and sleep. Mobile phone usage was assessed via passive mobile sensing; We used Chronicle for Android users and screen shots of iOS screen time metrics for iOS users. Participants were invited to complete a second, 14-day protocol approximately 3-12 months after their first assessment. We used Pearson correlations to examine preliminary convergent validity between validated questionnaire measures of stress and child behavior and EMA items. Root mean square errors (RMSE) were computed to examine the preliminary agreement between caregiver self-reported mobile phone use and objective phone use.

Results:

Of the 110 consented participants, 105 completed all study protocols (95% retention rate). Compliance was defined a priori as completing ≥70% of protocol tasks. There were high rates of protocol compliance for passive mobile sensing for both Android (97%) and iOS (98%) participants. EMA compliance was high (99%), but fewer caregivers and children met compliance (≥21 valid days) for accelerometry (60% & 42%, respectively). Average objective daily mobile phone use was 383.4 minutes (SD = 157.0) for Android participants and 354.7 (SD =137.6) for iOS users. Agreement with caregiver self-reported mobile phone use was poor; RMSE was 157.1, and 81.4 for Android and iOS users, respectively. Among families who completed the first assessment, 91 re-enrolled to complete the protocol a second time an average of 7 months later (86% retention rate).

Conclusions:

It is feasible to collect intensive longitudinal data on objective digital media use, simultaneously with accelerometry and EMA among an economically and racially diverse sample of families with preschool-aged children. The generally high levels of compliance and retention of the study sample are encouraging signs that these methods of intensive longitudinal data can be completed in a longitudinal cohort study. The lack of agreement between self-reported and objectively measured mobile phone use highlights the need for additional research using objective methods to measure digital media use.