Effectiveness of a chart prompt about immunizations in an urban health center

Strengths of this study include (1) it was a randomized, controlled trial with blinding of the investigators to the patients’ group status and (2) it was conducted in the real-life setting of health centers that serve underprivileged persons in the inner city. One of the limitations of the study is that nurse staffing became short midway through the project, and the prompt sheets were not prepared on some days. Thus, the results likely underestimate the magnitude of the true effect if the intervention had been perfectly staffed; however, the positive effect despite this problem shows the robustness of prompts. Because the study took place only in urban health centers in Pittsburgh, generalizability may be limited.

Another limitation is the length of time since the study was performed. However, national immunization statistics from 2000 (the most recent available data) show that only 76% of children in the United States between 19 and 35 months of age received all the immunizations recommended for children by 18 months of age.¹ This is a mere increase of 2 percentage points since 1995, the year in which this study was started. Since that time more vaccines have come into routine use, making it more difficult for children to be up to date on their immunizations. The health center sites used for this study still do not have computerized databases that allow for computer generation of vaccine reminders or recalls.

Because the greatest improvement was seen regarding immunizations given during the second year of life, when rates of age-appropriate immunizations tend to decrease, it might be reasonable to implement this type of an intervention focused on the age group of 12 to 24 months. This would allow limited resources to be concentrated on the population most likely to benefit.