Randomized study of online vaccine reminders in adult primary care.

Online immunization reminders were implemented in an adult medicine setting in which all immunization history, vaccine ordering and charting were required online. Physicians were randomized to one of two arms in a cross-over design. Each arm was shown online recommendations for vaccines indicated by nationally accepted guidelines either during the first or during the second part of the study period. The main purpose of the study was to assess the impact of reminders on correct decisions related to prescribing vaccines. Online reminders had the following impact on physician behavior: 1) Physicians used the application almost 3 times as often when shown reminders. 2) Physicians in the reminder group were 27% less likely to order a vaccine in the reminder group (P- value 0.0005). 3) Compliance with guidelines was improved significantly for Tetanus and for Hepatitis B in several analyses. No such effects were found for Pneumoccocal, Measles, or Influenza vaccines.