To Prompt or Not to Prompt? A Microrandomized Trial of Time-Varying Push Notifications to Increase Proximal Engagement With a Mobile Health App

Abstract

BackgroundMobile health (mHealth) apps provide an opportunity for easy, just-in-time access to health promotion and self-management support. However, poor user engagement with these apps remains a significant unresolved challenge.ObjectiveThis study aimed to assess the effect of sending versus not sending a push notification containing a contextually tailored health message on proximal engagement, measured here as self-monitoring via the app. Secondary aims were to examine whether this effect varies by the number of weeks enrolled in the program or by weekday versus weekend. An exploratory aim was to describe how the effect on proximal engagement differs between weekday versus weekend by the time of day.MethodsThe study analyzes the causal effects of push notifications on proximal engagement in 1255 users of a commercial workplace well-being intervention app over 89 days. The app employs a microrandomized trial (MRT) design to send push notifications. At 1 of 6 times per day (8:30 am, 12:30 pm, 5:30 pm, 6:30 pm, 7:30 pm, and 8:30 pm; selected randomly), available users were randomized with equal probability to be sent or not sent a push notification containing a tailored health message. The primary outcome of interest was whether the user self-monitored behaviors and feelings at some time during the next 24 hours via the app. A generalization of log-linear regression analysis, adapted for use with data arising from an MRT, was used to examine the effect of sending a push notification versus not sending a push notification on the probability of engagement over the next 24 hours.ResultsUsers were estimated to be 3.9% more likely to engage with the app in the next 24 hours when a tailored health message was sent versus when it was not sent (risk ratio 1.039; 95% CI 1.01 to 1.08; P<.05). The effect of sending the message attenuated over the course of the study, but this effect was not statistically significant (P=.84). The effect of sending the message was greater on weekends than on weekdays, but the difference between these effects was not statistically significant (P=.18). When sent a tailored health message on weekends, the users were 8.7% more likely to engage with the app (95% CI 1.01 to 1.17), whereas on weekdays, the users were 2.5% more likely to engage with the app (95% CI 0.98 to 1.07). The effect of sending a tailored health message was greatest at 12:30 pm on weekends, when the users were 11.8% more likely to engage (90% CI 1.02 to 1.13).ConclusionsSending a push notification containing a tailored health message was associated with greater engagement in an mHealth app. Results suggested that users are more likely to engage with the app within 24 hours when push notifications are sent at mid-day on weekends.

Occurrence of and Reasons for “Missing Events” in Mobile Dietary Assessments: Results From Three Event-Based Ecological Momentary Assessment Studies

“…Prompts such as push notifications can now utilize individuals’ contexts to determine the most opportune times to send prompts [ 62 ]. Interruptibility research has emerged within the field of human-computer interactions, along with text-messaging interventions in psychology and public health [ 63 ]. However, current findings from experimental studies indicate that although prompts may encourage greater exposure to message or intervention contents without deterring engagement, they do not always enhance their use [ 63 , 64 ].…”

“…Interruptibility research has emerged within the field of human-computer interactions, along with text-messaging interventions in psychology and public health [ 63 ]. However, current findings from experimental studies indicate that although prompts may encourage greater exposure to message or intervention contents without deterring engagement, they do not always enhance their use [ 63 , 64 ]. Morrison et al compared intelligent notifications, daily notifications within predefined time frames, and occasional notifications within predefined time frames in a stress management intervention and found generally low response rates but a small-to-medium effect on viewed and actioned notifications for the first two compared with occasional notifications.…”

Engagement with a Web-Based Health Promotion Intervention among Vocational School Students: A Secondary User and Usage Analysis

“…The low number of users for whom repeated engagement could be observed confirms this. Research suggests that periodic reminders and tailored prompts to use (web-based) health interventions can have a positive impact on engagement [77][78][79], especially if they are additionally combined with personal contact [80]; neither of these components was used in the present study. The optimal frequency still needs to be investigated [77,81], because a high frequency can also lead to "fatigue" and thus to ignoring [7].…”

Impact of a brief psychoeducational intervention for reducing alcohol use and related harm in school leavers

“…A key component of the RI intervention was introducing young people to Ray's Night Out app; however, few young people downloaded or used the app. This is a common problem in eMental Health research, as even if young people download an app (which was difficult in the school settings, as phones were banned in class), less than 20% will use the app more than once . Moreover, the Red Frogs facilitators had prior experience presenting SI, and the lack of fidelity checks meant that there was no way to determine if all SI/SR components were presented at seminars, or whether the presentation style was comparable between the SI and RI.…”