The influence of cost-effectiveness information on physicians' cancer screening recommendations

Physicians are increasingly faced with choices in which one screening strategy is both more effective and more expensive than another. One way to make such choices is to examine the cost-effectiveness of the more costly strategy over the less costly one. However, little is known about how cost-effectiveness information influences physicians' screening decisions. We surveyed 900 primary care US physicians, and presented each with a hypothetical cancer-screening scenario. We created three familiar screening scenarios, involving cervical, colon, and breast cancer. We also created three unfamiliar screening scenarios. Physicians were randomized to receive one of nine questionnaires, each containing one screening scenario. Three questionnaires posed one of the familiar screening scenarios without cost-effectiveness information, three posed one of the familiar scenarios with cost-effectiveness information, and three posed one of the unfamiliar scenarios with cost-effectiveness information. The cost-effectiveness information for familiar scenarios was drawn from the medical literature. The cost-effectiveness information for unfamiliar scenarios was fabricated to match that of a corresponding familiar scenario. In all questionnaires, physicians were asked what screening alternative they would recommend. A total of 560 physicians responded (65%). For familiar scenarios, providing cost-effectiveness information had at most a small influence on physicians' screening recommendations; it reduced the proportion of physicians recommending annual Pap smears (p=0.003), but did not significantly alter the aggressiveness of colon cancer and breast cancer screening (both p's<0.1). For all three unfamiliar scenarios, physicians were significantly less likely to recommend expensive screening strategies than in corresponding familiar scenarios (all p's<0.001). Physicians' written explanations revealed a number of factors that moderated the influence of cost-effectiveness information on their screening recommendations. Providing physicians with cost-effectiveness information had only a moderate influence on their screening recommendations for cervical, colon, and breast cancer. Significantly, fewer physicians recommended aggressive screening for unfamiliar cancers than for familiar ones, despite similar cost-effectiveness. Physicians are relatively reluctant to abandon common screening strategies, even when they learn that they are expensive, and are hesitant to adopt unfamiliar screening strategies, even when they learn that they are inexpensive.