Patient access to an electronic health record with secure messaging: impact on primary care utilization.

OBJECTIVE To determine whether patient access to secure patient-physician messaging affects annual adult primary care office visit and documented telephone contact rates. STUDY DESIGN Retrospective cohort and matched-control studies with pre-post analysis. METHODS The cohort study sample included 4686 adult members of Kaiser Permanente Northwest (KPNW) who had been registered KP HealthConnect Online users longer than 13 months and had used at least 1 feature. The matched-control study sample included 3201 randomly selected controls matched by age/sex, selected chronic conditions, and primary care physician to 3201 registered users. We calculated the difference in primary care office visit and documented telephone contact rates in the pre- and post-periods (defined, respectively, as 3-14 months before and 2-13 months after registration for KP HealthConnect Online). Paired t tests were used to assess significance. RESULTS Annual office visit rates decreased by 0.23 (-9.7%) visits per member in the cohort study. Annual office visit rates for users in the matched-control study decreased by 0.25 (-10.3%); the corresponding decrease for the controls was 0.08 (-3.7%). This 0.17 (-6.7%) reduction was significant (P < .003). Annual documented telephone contact rates for users in the matched-control design increased by 0.32 (16.2%) contacts per member; the corresponding rate for the control group was 0.52 (29.9%). This 0.20 (13.7%) difference was significant (P < .01). CONCLUSION Patient access to the secure messaging feature of KP HealthConnect Online was associated with decreased rates of primary care office visits and telephone contacts.