Inconsistencies in findings from the early lung cancer action project studies of lung cancer screening.

Long-standing guidelines against screening high-risk individuals for lung cancer may change following the publication of the randomized National Lung Screening Trial (NLST), which shows a benefit of computed tomography compared with chest x-ray screening. Guideline panels will likely also seek additional information from nonrandomized studies of computed tomography screening, such as the Early Lung Cancer Action Project (ELCAP). However, for the ELCAP findings to be incorporated into new guidelines, some inconsistencies in the published data should first be resolved. Specifically, some of the reports from ELCAP appear to contradict others in terms of important endpoints, and several findings from ELCAP appear to be statistically improbable or outliers when compared with analyses and studies by other research groups. Clarification of both internal and external inconsistencies is a prerequisite for evaluation of the body of work published by ELCAP investigators.