mography use, with an estimated intervention effect of 18.9 percent (95-percent confidence interval [CI]: 10.4-27.4; 14 studies). These studies all used multiple types of interventions; the majority involved some form of person-to-person contact in addition to access-enhancing strategies, such as mobile vans, transportation to appointments, facilitated appointments, and vouchers for low-cost or free mammograms. A recent report by Segura et al. (2001) supports this conclusion. The authors found that for low-income women in Spain, the combination of a personal letter of invitation and direct contact with women in their homes by a trained woman of similar age was most effective in motivating women to get mammograms.
The magnitude of the impact of individual-directed interventions in health care settings was nearly identical to that of access-enhancing strategies, with an estimated effect of 17.6 percent (95-percent CI: 11.6-24.0; 15 studies) (see Table 4-1). Individual-directed efforts in community settings yielded effects of 6.8 percent (95 percent CI: 1.8-11.8; 13 studies), whereas effect sizes for community education, media campaigns, and social network were 9.7 percent, 5.9 percent, and 5.8 percent based on 14, 6, and 7 studies, respectively.
The use of multiple intervention types was effective, with intervention effects averaging 13.3 percent overall (95-percent CI: 8.6-18.0; 26 studies). With the exception of social network interventions, the estimated intervention effects were significantly greater than zero for all of the groupings. However, each grouping exhibited significant heterogeneity. The most effective combination of intervention types appears to be access-enhancing interventions combined with individual-directed interventions. These studies had an estimated combined intervention effect of 26.9 (95-percent CI: 9.9-43.9; 9 studies). The next largest effect was for the 5 studies combining access-enhancing and system-directed interventions; their effects were 19.4 (95-percent CI: 8.2-30.6). Caution should be used in interpreting these results because the number of studies available to examine pairs of combinations was quite small.