Study Setting
We conducted a cohort analysis of all invited UCSF patients to identify predictors of enrollment. Data were extracted from the UCSF EHR system (Epic Systems Corporation) between September 2019 and December 2019, for sociodemographic, clinical diagnoses, health care use, and insurance coverage information at the time of the patient’s email invitation date. We limited the analysis to contacted patients, defined as those sent an email via Mailchimp that was not rejected by the patient’s email server.