Who are we reaching through the patient portal: engaging the already engaged?

A key assumption underlying the drive to increase patient use of a patient portal is that such use will increase patient engagement and activation. In this cross-sectional analysis we examine the question of who uses the patient portal, MyChart. Specifically, we examine the Patient Activation Measure (PAM) scores among patients receiving primary care in a large delivery system to assess how it relates to referrals to use the patient portal, as well as actual usage. A total of 16,357 patients are included in the analysis who had an office visit during a six-month period in 2010 and who had a PAM score in their EHR. The findings show that higher activated patients are more likely to be referred to the patient portal and among that group, the higher activated are more likely to actually use it. Policy and practice implications are discussed.