Effect of Incidental Findings Information on Lung Cancer Screening Intent: a Randomized Controlled Trial

Abstract

Background: The Centers for Medicare & Medicaid Services requires decision aid use for lung cancer screening (LCS) shared decision-making. However, it does not require information about incidental findings, a potential harm of screening.

Objective: To assess the effect of incidental findings information in an LCS decision aid on screening intent as well as knowledge and valuing of screening benefits and harms.

Design: Randomized controlled trial conducted online between July 16, 2020, and August 22, 2020.

Participants: Adults 55-80 years, eligible for LCS.

Intervention: LCS video decision aid including information on incidental findings or a control video decision aid.

Main measures: Intent to undergo LCS; knowledge regarding the benefit and harms of LCS using six knowledge questions; and valuing of six benefits and harms using rating (1-5 scale, 5 most important) and ranking (ranked 1-6) exercises.

Key results: Of 427 eligible individuals approached, 348 (83.1%) completed the study (173 intervention, 175 control). Mean age was 64.5 years, 48.6% were male, 73.0% white, 76.3% with less than a college degree, and 64.1% with income < $50,000. There was no difference between the intervention and controls in percentage intending to pursue screening (70/173, 40.5% vs 73/175, 41.7%, diff 1.2%, 95% CI - 9.1 to 11.5%, p = 0.81). Intervention participants had a higher percentage of correct answers for the incidental findings knowledge than controls (164/173, 94.8% vs 129/175, 73.7%, 95% CI - 28.4 to - 13.8%, p < 0.01). Incidental findings had the fifth highest mean importance rating (4.0 ± 1.1) and the third highest mean ranking (3.6 ± 1.5). There was no difference in mean rating or ranking of incidental findings between intervention and control groups (rating 4.0 vs 3.9, diff 0.1, 95% CI - 0.2, 0.3, p = 0.51; ranking 3.6 vs 3.6, diff 0.02, 95% CI - 0.3, 0.3, p = 0.89).

Conclusions: Incidental findings information in a LCS decision aid did not affect LCS intent, but it resulted in more informed individuals regarding these findings. In formulating screening preferences, incidental findings were less important than other benefits and harms.

Trial registration: ClinicalTrials.gov identifier: NCT04432753.

Keywords: Cancer screening; Decision aids; Lung cancer; Primary care; Shared decision-making.