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A randomized trial of the effectiveness of computer-generated telephone messages in increasing immunization visits
R W Linkins1, E F Dini, G Watson
1National Immunization Program, Centers for Disease Control and Prevention, Georgia Division of Public Health, Atlanta.
Insights
Computer-generated telephone reminders significantly increased preschool immunization visits, especially for children overdue for key vaccines. This simple intervention proves effective in boosting vaccination rates for essential childhood immunizations.
Area of Science:
- Public Health
- Preventive Medicine
- Health Communication
Background:
- Preschool immunization visits are crucial for child health.
- Low immunization rates for certain vaccines pose a public health challenge.
- Effective strategies are needed to improve vaccine uptake.
Purpose of the Study:
- To evaluate the efficacy of automated telephone messages in enhancing preschool immunization appointments.
- To determine if computer-generated reminders and recalls improve vaccination visit rates.
Main Methods:
- A randomized controlled trial was conducted across 14 counties in Georgia.
- 8002 children under two years old, with existing contact information, were enrolled.
- Participants were randomized to receive or not receive computer-generated telephone reminders/recalls for immunizations.
Main Results:
- Children receiving messages had higher immunization visit rates (36.3%) compared to the control group (28.4%).
- Actual message delivery led to a 41.1% immunization visit rate.
- Recall messages were more effective than reminder messages, particularly for children overdue for DTaP and MMR vaccines.
Conclusions:
- Computer-generated telephone reminders and recalls are a simple and effective method to increase preschool immunization visits.
- This strategy is particularly beneficial for improving rates of vaccines with historically lower coverage.
Objective:
To assess the effectiveness of computer-generated telephone reminder and recall messages in increasing preschool immunization visits.
Design:
Randomized, controlled trial.
Setting:
Fourteen counties in urban and rural Georgia.
Study Participants:
Children (N = 8002) who were younger than 2 years; had telephone numbers listed in preexisting computerized immunization databases; and were due or late for immunization(s) during the 4-month enrollment period.
Intervention:
Households of children were randomized to receive or not receive a general or vaccine-specific computer-generated telephone reminder or recall message the day before the child was due, or immediately after randomization if the child was late.
Main Outcome Measure:
The rates of immunization visits during the 30-day follow-up period.
Results:
Of the 4636 children whose households were randomized to receive a message, 1684 (36.3%) visited the health department within 30 days compared with 955 (28.4%) of the 3366 children whose households were not contacted (risk ratio [RR] = 1.28; 95% confidence interval [CI] = 1.20 to 1.37; P < .01). Immunization visits were more frequent (41.1%) among the 3257 children whose households actually received the message (RR = 1.45; 95% CI = 1.36 to 1.56; P < .01). Improvement in immunization visits was similar for general and specific messages, greater for recall than reminder messages, and greatest for children who were late for the third dose of the diphtheria-tetanus-pertussis vaccine and the measles-mumps-rubella vaccine.
Conclusion:
These data suggest a simple and effective way to increase preschool immunization visits, particularly for vaccines associated with the lowest immunization rates.
