Screening for disease.

Screening for disease has become a major activity over the last few decades, and the potential for future growth is almost boundless. However, the necessity for and effectiveness of screening has often been overstated with misused survival statistics. Nevertheless, screening with certain radiologic tests may provide modest benefits at acceptable costs under certain conditions. The challenge for the future is to better identify the tests, populations, and other conditions under which screening is appropriate. Various quantitative techniques for eliciting patient preferences 76 and analyzing benefits, harms, and costs over time 77-80 may help us meet this challenge.