THE CONTRIBUTION OF MISSED OPPORTUNITIES TO CHILDHOOD UNDERIMMUNIZATION IN BALTIMORE

Objective. To determine the community-wide incidence of missed opportu nities to vaccinate, to describe the clinical settings in which they o ccur, and to estimate the impact of missed opportunities on immunizati on coverage. Design and Methods. We abstracted outpatient medical reco rds from a random, community-based sample of 2-year-old children whose residence was inner-city Baltimore. The date of each vaccine and the date, diagnoses, and temperature at each visit were collected for 502 children at 98 different provider sites. Main Outcome Measures. Missed opportunities to vaccinate and up-to-date vaccination status. Results . By 24 months of age, 75% of the children had at least one missed opp ortunity and only 55% were up-to-date for the 4:3:1 series. Missed opp ortunities occurred at more than one third of eligible visits for each vaccine, including >20% of preventive care visits. Diagnoses commonly associated with missed opportunities were ''well child,'' otitis medi a, upper respiratory infection, gastroenteritis, skin infection, and r esolving illness. if no missed opportunities had occurred, 73% of the children would have been up-to-date by 24 months.Conclusions. Missed o pportunities occurred commonly at providers serving inner-city childre n in Baltimore and represent a major factor in underimmunization. Redu ction of missed opportunities by accurate screening at all visits and adherence to the contraindication guidelines is a provider-based, low- cost method to increase immunization coverage.