The effectiveness of assessment and referral on immunization coverage in the special supplemental nutrition program for women, infants, and children.

Background: The use of immunization assessment and referral (A/R) in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) has been shown to produce dramatic improvements in vaccination coverage when coupled with parental incentive; however, data are lacking to support the use of A/R alone.

Objective: To determine the effectiveness of A/R in increasing immunization coverage among WIC participants.

Design: Participating WIC centers were assigned to1 of 3 interventions that delivered A/R of varying frequency or a control group.