Addressing knowledge and attitude barriers to lung cancer screening: Development and evaluation of web-based decision aid

•We developed a web-based decision aid for the general population (aged 40–79) to help them decide on lung cancer screening.•A pre–post comparison analysis showed that the decision aid improved knowledge and attitudes about lung cancer screening.•The decision aid did not significantly alter screening intentions. Low-dose computed tomography screening reduces lung cancer and overall mortality, but the participation rate remains low. The objective of this study was to develop a decision aid (DA) that addresses the overabundance of healthcare options and barriers to participation in lung cancer screening (LCS) among the general population aged 40–79 years in Korea. The DA was developed by following the International Patient Decision Aid Standards process. To evaluate the DA, participants aged 40–79 years were purposively sampled from four districts of the Seoul metropolitan area, with 25 individuals from each decade of the age range. Participants used the DA for LCS, and pre–post comparison was conducted. The primary outcome was a change in intention to undergo LCS after completing the DA. The secondary outcomes were changes in knowledge and attitude about LCS, decisional conflict, and the perceived usefulness of the DA. The DA prototype contained lung cancer risk assessment and decision-making components that addressed knowledge, risks, benefits, costs, and personal values. In a pilot study of 100 participants (mean age 59.0 [SD 11.1] years, 80 % male, 25 % of whom had undergone LCS), knowledge about LCS increased (mean [SD] score [out of 100] before vs. after: 68.3 [13.4] vs. 73.6 [18.0], p