Importance Screening for lung cancer has the potential to reduce mortality, but in addition to
detecting aggressive tumors, screening will also detect indolent tumors that otherwise may
not cause clinical symptoms. These overdiagnosis cases represent an important potential
harm of screening because they incur additional cost, anxiety, and morbidity associated with
cancer treatment. Objective To estimate overdiagnosis in the National Lung Screening Trial
(NLST). Design, Setting, and Participants We used data from the NLST, a randomized trial …