This study assessed efficacy of three reminder types (EUCRs, ATRs, and ELRs) on repeat mammography adherence for women with previous mammograms who were due for their next screening. Interventions produced adherence proportions ranging from 72% to 76%. These rates reflect an absolute increase of nearly 18% when compared to pre-intervention rates of repeat mammography adherence. Findings confirm previous research documenting the effectiveness of reminders on mammography use,14,19,32
but they extend these findings to include ATRs.
Comparisons of the three reminders suggest that ATRs are the most effective strategy to increase repeat mammography adherence for women with recent mammograms. Rates of repeat mammography adherence for women in the ATR group were higher (an absolute difference of 4.5%) than for those who received EUCRs containing similar content. This finding was stable across key sample characteristics including race, education, and work status. Of the three reminders, ATRs also cost the least, at an estimated $0.35 per intended recipient.
There are several potential explanations for why ATRs yielded higher rates of repeat mammography adherence compared to EUCRs. The ATRs may have reached a larger proportion of intended recipients than printed reminders, although it was not possible to test this hypothesis. Multiple attempts (an average of three) were made to deliver automated messages, whereas only one printed reminder was sent (unless returned as undeliverable). One clear advantage of ATRs is that the number can be automatically redialed if the message is not delivered successfully, which could have resulted in greater delivery success. Further analyses provided by the ATR vendor showed that they successfully delivered calls for 1168 (86.2%) participants. Although the delivery success rate for study printed materials is not known, it is possible that not all women received them or read them in their entirety. It is also possible that participants viewed ATRs as an appealing and credible channel of communication about mammography. Research suggests that recorded health messages typically are viewed as credible,47,48
especially when characteristics of recipients, such as gender, are matched to those of message senders.49
Although this study did not assess message credibility and appeal, future studies on ATRs might benefit by including these measures.
Effects for ELRs were similar to those for EUCRs (74.5% and 71.8% adherence, respectively). There are several possible reasons the differences were slight. Core content was very similar across reminders. All reminders provided dates of women’s previous mammograms, noted the benefits of mammography, and stated recommended mammography guidelines and health plan coverage. The ELRs were enhanced in that they included theory-guided information on breast cancer severity and susceptibility, as well as mammography facility names and telephone numbers. The ELRs also differed from EUCRs in appearance. Despite these differences, the fundamental message conveyed in these two reminders was essentially the same, and this may have been sufficient to influence behavior. Also, ELRs contained more pages and text than EUCRs, thus requiring more effort from participants. Women may not have read ELR booklets in their entirety. The study design did not permit us to disaggregate the impact of each of these elements to determine why differences between ELRs and EUCRs were slight.
Other study variables were associated with repeat mammography adherence. Women who were adherent to repeat mammography prior to study enrollment were much more likely to respond to reminders compared to those who were non-adherent to repeat mammography prior to study enrollment (86.8% and 58.5%, respectively). This finding is consistent with other mammography studies showing that past screening behaviors strongly predict future mammography use.50–53
Also consistent with previous research is the finding that black women, those who reported financial hardship, and those in poorer health were less likely to have repeat mammograms.6,50,54,55
More intense intervention efforts probably will be needed for these groups. Findings also showed that women in their forties were less likely to be adherent to repeat mammography compared to women aged 50–75 years. Differences in health insurance coverage may explain this finding. At the time of PRISM intervention, the SHP covered mammograms every year for women aged ≥50 years, and every other year for women in their forties. The SHP now has extended annual coverage of mammograms to women aged ≥35 years. Lingering confusion over screening guidelines for women in their forties may also have contributed to this finding.56
The current study focused on repeat mammography for insured women with recent mammograms. Although effective for this study population, ATRs are not an appropriate intervention for women without access to health care or those who have never had mammograms. Also, findings cannot be generalized to minority women other than black women because there were too few ethnic and racial minority women in the sample to analyze their data. The delivery success rate and efficacy of ATRs for racial/ethnic minorities other than black women and/or non-English speakers are not known.
This research should be viewed within the larger context of PRISM, which seeks to find the minimal intervention needed for sustained annual-interval mammography use. These analyses did not address two important questions: (1) Are reminders efficacious over time if delivered regularly?; (2) What is the incremental effect of more intensive intervention—tailored printed materials and telephone counseling—for women who became delayed? Future PRISM research will seek to answer these questions. Also, although study interventions promoted annual mammography, efficacy is not likely to differ substantially for other screening intervals (e.g., biennial screening), although outcomes might be slightly larger with longer screening intervals. It is hypothesized that findings would be very similar if disseminated within a health plan or organization with similar mammography coverage. Researchers designed interventions with potential dissemination as a major consideration and conducted research within a defined population of health plan members.