JMIR Publications

ABSTRACT

Background:

Despite the growing number of mobile health (mHealth) interventions targeting childhood obesity, few studies have characterized user typologies derived from individuals’ patterns of interactions with specific app features (digital phenotypes).

Objective:

This study identified digital phenotypes among 214 parent-child dyads who used the Aim2Be mHealth app as part of a randomized control trial conducted in 2019-2020, and explored whether participants’ characteristics and health outcomes differed across phenotypes.

Methods:

Latent Class Analysis (LCA) was used to identify distinct parent and child phenotypes based on their use of the app’s behavioral, gamified and social features over 3 months. Multinomial logistic regression models assessed whether phenotypes differed by demographic characteristics. Covariate-adjusted mixed-effect models evaluated changes in body mass index z-scores (zBMI), diet, physical activity and screen time across phenotypes.

Results:

Among parents, 5 digital phenotypes were identified: Socially engaged (16%); Independently engaged (9%) (parents who used the behavioral or the social features of the app, respectively), Fully engaged (12%); Partially engaged (15%), and Unengaged (48%). Married parents were more likely to be Fully engaged as opposed to Independently engaged or Unengaged. Socially engaged parents were older than Fully engaged and Unengaged parents. LCA revealed 4 phenotypes among children: Fully engaged (15%); Partially engaged (28%); Dabblers (20%) and Unengaged (37%). Fully engaged children were younger than Dabblers and Unengaged children. Dabblers lived in higher income households compared to Fully and Partially engaged children. Fully engaged children were more likely to have Fully and Partially engaged parents than Unengaged children. Compared to Unengaged children, Fully and Partially engaged children decreased their total sugar and energy intakes. Partially engaged children also decreased their sugary beverage intake compared to Unengaged children. Similarly, children with Fully engaged parents decreased their zBMI whereas children with Unengaged parents increased their zBMI over time. Finally, children with Independently engaged parents decreased their calorie intake whereas children with Unengaged parents increased their caloric intake over time.

Conclusions:

Full parent-child engagement is critical for the success of mHealth interventions. Further research is needed to understand program design elements that can affect participants’ engagement to support behavior change. Clinical Trial: ClinicalTrials.gov (NCT03651284). Registered 29 August 2018, https://clinicaltrials.gov/ct2/show/NCT03651284.