Computed tomography screening: the international early lung cancer action program experience.

The International Early Lung Cancer Action Program (I-ELCAP) used a novel study design that provided quantitative information about annual CT screening for lung cancer. The results stimulated additional studies of lung cancer screening and ultimately led to the National Lung Screening Trial (NLST) being initiated in 2002, as the initial report in 1999 was sufficiently compelling to reawaken interest in screening for lung cancer. The authors think that the I-ELCAP and NLST "story" provides a strong argument for relevant agencies to consider alternative study designs for the public funding of studies aimed at evaluating the effectiveness of screening and other medical trials.