JMIR Publications

ABSTRACT

Background:

Adherence to online behaviour change interventions is one of the main challenges impacting long-term efficacy. Better understanding of baseline user characteristics can improve design and fit.

Objective:

We aim to understand the impact of users’ characteristics and the first 24h usage patterns of a web-platform for weight loss on user engagement and weight loss in the long-term (6 months).

Methods:

Data from participants of the POEmaS randomised controlled trial, which compared a weight loss platform, platform plus coach and control, were analysed. Data included baseline behaviour and usage logs from initial 24h after platform access. Latent profile analysis (LPA) was used to identify classes and Kruskal-Wallis was used to test whether class membership was associated with long-term (24 weeks) adherence and weight loss.

Results:

Among 828 participants assigned to intervention arms, three classes were identified through LPA: Motivated Healthy (better baseline health habits, high 24h platform use), Indifferent Majority (balanced), Unhealthy Quitters (worse habits and low 24h platform use). Class membership was associated with long-term adherence (p<0.001), and Unhealthy Quitters had the lowest adherence. Weight loss was not associated with class membership (p=0.49), regardless of the intervention arm (platform or platform plus coach). However, Indifferent Majority users assigned to platform plus coach lost more weight than those assigned to platform only (p=0.02).

Conclusions:

Baseline questionnaires and usage data from the first 24h after login allowed distinguishing classes, which were associated with long term adherence. This suggests that this classification might be a useful guide to improve engagement and select interventions to individual users. Clinical Trial: ClinicalTrials.gov NCT03435445; https://clinicaltrials.gov/ct2/show/NCT03435445.