Increasing immunization rates among inner-city, African American children. A randomized trial of case management

Abstract

Context: Immunization rates in the inner city remain lower than in the general US population, but efforts to raise immunization levels in inner-city areas have been largely untested.

Objective: To assess the effectiveness of case management in raising immunization levels among infants of inner-city, African American families.

Design: Randomized controlled trial with follow-up through 1 year of life.

Setting: Low-income areas of inner-city Los Angeles, Calif.

Patients: A representative sample of 419 African American infants and their families.

Interventions: In-depth assessment by case managers before infants were 6 weeks of age, with home visits 2 weeks prior to when immunizations were scheduled and additional follow-up visits as needed.

Main outcome measures: Percentage of children with up-to-date immunizations at age 1 year, characteristics associated with improved immunization rates, and cost-effectiveness of case management intervention.

Results: A total of 365 newborns were followed up to age 1 year. Overall, the immunization completion for the case management group was 13.2 percentage points higher than the control group (63.8% vs 50.6%; P=.01). In a logistic model, the case management effect was limited to the 25% of the sample who reported 3 or fewer well-child visits (odds ratio, 3.43; 95% confidence interval, 1.26-9.35); for them, immunization levels increased by 28 percentage points. Although for the case management group intervention was not cost-effective ($12022 per additional child immunized), it was better ($4546) for the 25% of the sample identified retrospectively to have inadequate utilization of preventive health visits.

Conclusions: A case management intervention in the first year of life was effective but not cost-effective at raising immunization levels in inner-city, African American infants. The intervention was demonstrated to be particularly effective for subpopulations that do not access well-child care; however, currently there are no means to identify these groups prospectively. For case management to be a useful tool to raise immunizations levels among high-risk populations, better methods of tracking and targeting, such as immunization registries, need to be developed.