Background: New “e-Cohort” study designs provide resource-effective methods for collecting participant data. It is unclear if implementing an e-cohort without direct, in-person participant contact can achieve successful participation rates. The FHS-HeH randomized pilot study compared two distinct implementation strategies for co-enrolling participants from the Framingham Heart Study (FHS) into the Health eHeart Study, a digital cohort with infrastructure for collecting mHealth data.
Methods: FHS participants who had an email address and smartphone were randomized to one of two approaches: remote vs. on-site support. In the remote arm, participants received an email containing an enrollment URL, and, upon enrollment, were sent four Bluetooth sensor devices. Participants in the on-site arm were invited to visit FHS and were provided in-person support for enrollment and connecting the devices.
Results: Compared to participants that declined, individuals that accepted an invitation to participate in our pilot study (n=101 remote, n=101 on-site) were more often women, highly educated, and younger (Figure 1). All on-site participants completed the consent, compared to 93% of the remote arm. Of participants who consented to participate, connection and initial use of devices was also higher in the on-site arm (100% connected the activity monitor, 94% the blood pressure cuff and scale, and 84% the electrocardiogram) compared to the remote arm (74%, 75%, 80%, and 42%). Roughly 75-78% of those that initially connected in both arms were still using the devices by the 3rd month and 58-60% were still participating by the 6th month.
Conclusions: Our pilot study demonstrated that deployment of mobile devices among middle-aged and older adults in the context of an on-site clinic visit was associated with higher initial rates of device use as compared to offering only remote support. Once connected, drop-off rates were similar in both groups.