Seniors' preferences for cancer screening and medication use based on absolute risk reduction

This study was conducted to determine the influence of patient perceptions of absolute risk on choices for cancer screening and use of medications to prevent heart attack, stroke, and hip fracture.

At the end of routine office visits, we surveyed all eligible consecutive patients who visited four geriatricians in a Denver practice between November 8, 1993, and February 9, 1994.

We saw a total of 675 outpatients during the study period and completed the interview with 409 patients (75% female, mean age 81, 78% Caucasian). We found a strong correlation between (i) increased probability of detecting cancer and greater preference for cancer screening tests (p <.001) and (ii) increased probability of preventing disease (heart attack, stroke, or hip fracture) and greater preference for preventive medication (p <.0001). There was notable variability in seniors' preferences for a given therapy at each absolute risk threshold. For example, 15% of seniors did not think that highly effective, inexpensive medications to prevent heart attacks were worthwhile for them. At the other end of the spectrum, 22% of seniors felt that low-yield, costly medications to prevent heart attacks were worthwhile.

Seniors readily understand the probability of benefit expressed in terms of absolute risk reduction. Furthermore, probability of benefit strongly influences seniors' preferences for cancer screening and preventive medication use. Finally, there is variety in the thresholds of prevention at which individuals are willing to accept preventive treatment. The probability of benefit is an essential and useful element for seniors to make informed decisions about routine health services.