Impact of resident feedback on immunization outcomes.

OBJECTIVE To investigate the effect on immunization levels of retrospective written feedback to residents regarding missed immunization opportunities. DESIGN Randomized trial with control group. SETTING Pediatric resident continuity clinic in an urban hospital-based primary care clinic. PARTICIPANTS Thirty-two postgraduate level 2 and postgraduate level 3 pediatric residents. INTERVENTION Monthly retrospective written feedback mailed to residents detailing their missed immunization opportunities and appointment failure rates over a 12-month period beginning in February 1997. MAIN OUTCOME MEASURES The immunization level of 2-year-old children in the resident clinic was the main outcome of interest. Secondary outcomes included missed immunization opportunity rates and appointment failure rates. RESULTS Postintervention immunization levels were 71.4% (95% confidence limits [CLs]: 63.2%, 78.7%) for patients from the intervention group and 68.5% (95% CLs: 60.8%, 75.4%) for patients from the control group. The immunization level for patients of both groups who had fewer than 2 visits during the second year of life was 47.2% (95% CLs: 38.2%, 56.3%). This compares with an immunization level of 78.1% (95% CLs: 66.0%, 87.5%) for patients from both groups who had 2 visits during the second year of life, and with an immunization level of 88.2% (95% CLs: 81.0%, 93.4%) for patients of both groups who had more than 2 visits during the second year of life (P<.001). CONCLUSIONS In this setting, written retrospective feedback to residents was an ineffective strategy for improving immunization levels. Adequate follow-up during the second year of life is critical in achieving high immunization levels.