Objective: To investigate whether a reported rise in vaccination coverage in Georgia public clinics during the period 1988 through 1994 was artifactual or real and, if real, to determine the extent to which the rise could be associated with a program of measurement and feedback.
Design: Examination of data from Georgia public clinics, doses-administered records, and National Health Interview Surveys.
Setting/participants: Children attending Georgia public clinics.
Intervention: Measurement of vaccination coverage and feedback to providers.
Main outcome measure: Vaccination coverage rates.
Results: For the period 1988 through 1994, 136 004 Georgia public clinic vaccination records for children 21 to 23 months of age were reviewed. Median series-completion rates at public clinics rose from 53% to 89%, while indexes of under-vaccination fell: missed opportunities for simultaneous vaccination (6% to 0%), lost contact for more than 12 months (14% to 1%), and first vaccination more than 1 month late (19% to 8%). According to the independent doses-administered database, the proportion of children starting the primary series very late (> or =12 months old) fell from 14% to 6%, and the series-completion index rose from 64% to 83%, suggesting that improvements could not be wholly ascribed to better clinic record keeping. In 1988, vaccination coverage of children 24 months of age in the National Health Interview Survey (NHIS) was 53%, identical to median public clinic coverage in Georgia; in 1993, NHIS coverage was 60%, while median public clinic coverage in Georgia was 90%, suggesting that the rise in coverage in Georgia public clinics exceeded national trends. Patterns within the coverage changes suggest an association with the process of measurement and feedback.
Conclusions: A marked increase in vaccination coverage occurred in Georgia public clinics associated with a program of annual measurement and feedback.