Effectiveness of telephone reminders and home visits to improve measles, mumps and rubella immunization coverage rates in children

BACKGROUND: In the Saskatoon Health Region (SHR), Canada, 67.4% of children are fully immunized for measles, mumps and rubella (MMR) at 24 months of age, with 43.7% of low-income children fully immunized. METHODS: Parents of children who were behind in MMR immunizations were contacted to determine knowledge, beliefs toward and barriers to immunization. The effectiveness of a telephone reminder system in improving immunization rates in a health region compared with a control health region was determined. Finally, the effectiveness of telephone reminders versus telephone reminders combined with home visits in improving child immunization coverage rates in low-income neighbourhoods was compared. RESULTS: The survey was completed by 629 parents (69% response rate). Surprisingly, 81.8% were not aware that their child was behind in immunizations. In the SHR, the MMR immunization coverage increased from 67.4% to 74% in the first year of intervention (Rate Ratio= 1.10; 95% CI 1.08 to 1.12). All four neighbourhood groupings (three urban by income and one rural) had relative increases ranging from 9% to 11%. The control health region observed an immunization coverage increase from 66.5% to 69.2% in the first year (Rate Ratio= 1.04; 95% CI 1.01 to 1.07). The three low-income neighbourhoods with telephone reminders had an immunization coverage rate of 48.7% (95% CI 39.5% to 57.8%). The three low-income neighbourhoods that received a telephone reminder and home visit had an immunization coverage rate of 60.5% (95% CI 52.5% to 68.6%). CONCLUSIONS: Telephone reminder systems have benefit in increasing child immunization coverage rates.