Usage, adherence and attrition: How new mothers engage with a nurse-moderated web-based intervention to support maternal and infant health. A 9-month observational study

Objectives To identify factors predicting use, adherence and attrition with a nurse-moderated web-based group intervention designed to support mothers of infants aged 0-6 months. Design 9-Month observational study. Setting Community maternal and child health service. Participants 240 mothers attending initial postnatal health checks at community clinics who were randomly assigned to the intervention arm of a pragmatic preference randomised trial (total randomised controlled trial, n=819; response rate=45%). Intervention In the first week (phase I), mothers were assisted with their first website login by a research assistant. In weeks 2-7 (phase II), mothers participated in the web-based intervention with an expectation of weekly logins. The web-based intervention was comparable to traditional face-to-face new mothers' groups. During weeks 8-26 (phase III), mothers participated in an extended programme at a frequency of their choosing. Primary outcome measures Number of logins and posted messages. Standard self-report measures assessed maternal demographic and psychosocial characteristics. Results In phase II, the median number of logins was 9 logins (IQR=1-25), and in phase III, it was 10 logins (IQR=0-39). Incident risk ratios from multivariable analyses indicated that compared to mothers with the lowest third of logins in phase I, those with the highest third had 6.43 times as many logins in phase II and 7.14 times in phase III. Fifty per cent of mothers logged-in at least once every 30 days for 147 days after phase I and 44% logged-in at least once in the last 30 days of the intervention. Frequency of logins during phase I was a stronger predictor of mothers' level of engagement with the intervention than their demographic and psychosocial characteristics. Conclusions Mothers' early use of web-based interventions could be employed to customise engagement protocols to the circumstances of individual mothers with the aim of improving adherence and reducing attrition with web-based interventions.