Provider Chart Audits and Outreach to Parents: Impact in Improving Childhood Immunization Coverage and Immunization Information System Completeness

Background:
Immunization information systems (IIS) can identify children not up-to-date (NUTD) for immunizations. These children can then receive targetted interventions to promote immunization.

Objectives:
Examine impact of provider chart audits and parental outreach in improving immunization coverage among children NUTD for immunizations in Philadelphia's IIS.

Methods:
We identified 10-month old children born November 2003 - October 2004 and NUTD for age-appropriate immunizations using Philadelphia's IIS. Immunization rates at 10, 13, 19 months were compared before and after contact with providers and parents.

Results:
Of 5,610 children NUTD in the IIS at 10 months, provider chart audits confirmed that 3,612 (64%) were actually up-to-date (UTD); the majority of these (2,203) received additional age-appropriate immunizations and were also UTD at 19 months. Of 1,998 (36%) children truly NUTD at 10 months, half received immunizations overdue at 10 months by 13 months following parental outreach via telephone, postcards and home visits. Only 23% of children truly NUTD at 10 months were UTD at 19 months.

Conclusions:
Provider chart audits improved IIS data completeness. Providers must improve timely submission of information to the IIS so health department effort is not spent seeking already-administered immunizations. Among children truly NUTD at 10 months, parental outreach likely contributed to half receiving overdue immunizations by 13 months. However, most were again NUTD at 19 months, indicating that outreach efforts for children NUTD at 10 months should be continued through 19 months. Furthermore, in spite of outreach, about half of children NUTD at 10 months were not brought UTD by 13 or 19 months. New strategies should be developed to ensure that these children receive recommended vaccinations.