Differences in usage and engagement rates of an online physical activity intervention among subgroups of adults aged 50 years and older in a practical setting

BACKGROUND: Reach, use and effects of digital health interventions (DHIs) vary greatly among subpopulations, with lower usage rates and effects among groups with low socioeconomic status (SES) and chronic diseases. However, reaching these groups and improving their DHI use is crucial since they could benefit the most from improving their health and lifestyle. The aim of this study was to provide insight into usage and engagement rates of an online physical activity (PA) intervention among adults aged 50 years and older with a focus on differences between educational level (low vs. middle vs. high) and chronic disease (with vs. without) subgroups.

METHODS: A field study was performed where 400 adults aged 50 years and older received access to the AcTive-Plus intervention consisting of an activity tracker and three online tailored PA advisory sessions, which provide among others feedback on current PA behavior and personal suggestions for increasing PA. The concepts attrition, intervention use, motivation (five-point scale), appropriateness (ten-point scale) and engagement (Twente Engagement with Ehealth Technologies Scale, maximum score of 15) were assessed via software log data and online questionnaires. Chi-squares and Analyses of covariance were performed to test for differences between educational level and chronic disease subgroups with regard to the mentioned concepts ( P  ≤ .05).

RESULTS: Participants were categorized into low (≤ intermediate general secondary education) ( N  = 148), middle ( N  = 147) and high (≥ higher vocational education) ( N  = 105) education and into chronic disease ( N  = 200) and no chronic disease ( N  = 200) subgroups. Attrition from inclusion to baseline was 35%. Of the baseline-completers, respectively 60%, 42% and 72% completed advisory session 1, 2 and 3. Intervention motivation (advisory sessions mean = 3.6, standard deviation = 0.8; activity tracker M = 3.9, SD = 1.0), fit (M = 6.8, SD = 1.8) and engagement (M = 11.1–11.3, SD = 2.5–2.8) for the total study population were relatively high. No differences were found between subgroups on attrition, intervention use, motivation, appropriateness and engagement. With regard to intervention use, the middle education group (69%) was more likely (χ 2  = 9.606, P  = .048) to complete advisory session 1 than the low education group (51%).

CONCLUSIONS: There are indications that AcTive-Plus is accepted by adults aged 50 years and older with different educational backgrounds and health status when implemented in practice. However, the relatively high enrolment attrition rates and exploratory nature of the study need to be taken into account. The specific attention paid to low education and chronic disease groups during intervention development, optimization and recruitment is considered an important contributor for these exploratory findings. Therefore, DHI researchers and practitioners are recommended to involve these subgroups during intervention development, evaluation and implementation.

CLINICAL TRIAL NUMBER: Not applicable.

SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-025-25866-4.