Effect of 2 urban emergency department immunization programs on childhood immunization rates.

BACKGROUND: Emergency departments (EDs) are recommended as sites for immunizing children. However, there is little information about the effect of ED immunization programs on immunization rates. OBJECTIVES: To assess the ability of 2 ED immunization programs to vaccinate children and to measure the effect of the programs on immunization rates after the ED visit and 6 months later. DESIGN: A prospective cohort study. Emergency department patients were screened for immunization status, and vaccinations were offered to patients who either were documented to be eligible or were eligible by age and had no documented records. A systematic, sequential sample of those accepting vaccinations (study patients) was compared with a systematic, sequential sample of those not vaccinated (control subjects). Telephone interviews and medical record reviews were performed 6 months after the ED visit to verify dates of immunizations. Results were weighted to reflect the sampling frames of patients screened by the 2 programs. SETTING: Two EDs in New York City (in Manhattan and the Bronx) and the surrounding primary care offices. PATIENTS: Children (aged 0-6 years) screened for immunization status by the ED immunization program during a 10-week period; these included 210 children from the Manhattan ED (106 vaccinated in the ED) and 274 children from the Bronx ED (129 vaccinated in the ED). INTERVENTION: Emergency department immunizations. MAIN OUTCOME MEASURES: Proportion of patients (vaccinated, not vaccinated, and ED population) up-to-date for immunizations (1) at the time of the ED visit, (2) 1 day later, and (3) 6 months later. RESULTS: Two thirds of the patients in each ED had Medicaid, and one tenth were uninsured. At the time of the ED visit, 20% of the vaccinated children in each ED were actually up-to-date and were unnecessarily vaccinated; 74% (Manhattan ED) and 72% (Bronx ED) of the not vaccinated children were up-to-date (the remainder were later determined to have been eligible for vaccinations). One day after the ED visit, and 6 months later, the immunization rates of the vaccinated and not vaccinated children were similar. The results of the weighted analysis were as follows: for the entire ED population screened for immunization status, compared with up-to-date rates at the time of the ED visit, rates 1 day later were 11% (Manhattan ED) and 8% (Bronx ED) higher in each ED (P < .05); and rates 6 months later were the same in the Manhattan ED and 10% lower in the Bronx ED (P < .01). Eighteen percent of all children screened for immunization status were vaccinated; 10 to 15 children were screened and 2 to 4 children were vaccinated per 8-hour ED shift. CONCLUSIONS: This ED immunization program temporarily improved the immunization rates of the ED population, but substantial personnel time was required to achieve these small gains. Urban ED immunization programs are unlikely to be cost-effective.