Clinician Variation in Ordering and Completion of Low-Dose Computed Tomography for Lung Cancer Screening in a Safety-Net Medical System

Background: Less than 5% of eligible individuals in the United States undergo lung cancer screening. Variation in clinicians’ participation in lung cancer screening has not been determined. Patients and Methods: We studied medical providers who ordered ≥ 1 low-dose computed tomography (LDCT) for lung cancer screening from February 2017 through February 2019 in an integrated safety-net healthcare system. We analyzed associations between provider characteristics and LDCT orders and completion using chi-square, Fisher exact, and Student t tests, as well as ANOVA and multinomial logistic regression. Results: Among an estimated 194 adult primary care physicians, 144 (74%) ordered at least 1 LDCT, as did 39 specialists. These 183 medical providers ordered 1594 LDCT (median, 4; interquartile range, 2-9). In univariate and multivariate models, family practice providers (P < .001) and providers aged ≥ 50 years (P = .03) ordered more LDCT than did other clinicians. Across providers, the median proportion of ordered LDCT that were completed was 67%. The total or preceding number of LDCT ordered by a clinician was not associated with the likelihood of LDCT completion. Conclusion: In an integrated safety-net healthcare system, most adult primary care providers order LDCT. The number of LDCT ordered varies widely among clinicians, and a substantial proportion of ordered LDCT are not completed.