Limitations
RECRUITMENT
This study had important limitations. First, the way in which patients were included in our recruitment campaign may be a source of selection bias. Despite Health eHeart’s broad eligibility criteria, UCSF patients with documented email addresses were also those with MyChart patient portal accounts, for which there are known baseline differences across patient populations. There are also inherent differences among patients who list English as their preferred language compared to those who do not. Second, recruitment was restricted to UCSF patients who are not representative of the regional or general population. It has also been reported that “university-led” studies have higher levels of participation [