Nodule Characteristics, Clinical Risk Factors, and Radiologist Experience as Predictors of Positive Baseline LDCT...

Background/Objectives: Early detection of lung cancer through low-dose computed tomography (LDCT) significantly improves patient outcomes. Identifying predictors of positive baseline LDCT findings can optimize screening programs and cost-effectiveness, particularly in regional settings. Methods: We conducted a retrospective analysis of baseline LDCT screenings performed in 2024 at three sites in Vojvodina, Serbia. Eligible participants were adults aged 50-74 years with a significant smoking history. Lung nodules were evaluated using the Lung-RADS system. Sociodemographic, clinical, and nodule-related variables, as well as radiologist experience (>10 vs. <10 years), were assessed. Multivariable logistic regression identified independent predictors of positive LDCT outcomes (Lung-RADS 3, 4A, 4B, 4X). Results: Overall, 17.6% (613/3479) of participants had positive baseline LDCT findings. Multivariable analysis showed that nodule type (semi-solid: OR = 4.01, 95% CI: 1.46-11.01; solid: OR = 8.86, 95% CI: 4.53-17.32), nodule morphology (smooth: OR = 0.42, 95% CI: 0.22-0.81; perifissural: OR = 0.16, 95% CI: 0.08-0.33; endobronchial: OR = 47.99, 95% CI: 12.35-186.58), nodule diameter (OR = 1.83 per mm, 95% CI: 1.71-1.96), presence of COPD (OR = 1.95, 95% CI: 1.23-3.08), age (OR = 1.02 per year, 95% CI: 1.00-1.04), and radiologist <10 years working experience (OR = 1.47, 95% CI: 1.23-3.08) were independent predictors of positivity. Conclusions: Baseline LDCT positivity is influenced by nodule characteristics, patient sociodemographic and clinical factors, and radiologist experience. These findings can inform targeted screening strategies in high-risk populations.