Table 3.

Effect of lung screening by LDCT on lung cancer–related mortality in the two study populations of the National Lung Screening Trial (NLST) determined by the center's distribution of sex.

Cohort	Estimated effect [HR (95% CI)]	Generalized/transported effect [HR (95% CI)] from the estimated effect in the trial sample using inverse-odds weighting approacha,b
Trial sample: 23 centers with females ≥40%	0.82 (0.71–0.94)	—
Target population: 10 centers with females <40%	0.90 (0.72–1.09)	0.89 (0.71–1.08)
Total NLST	0.84 (0.76–0.95)	0.84 (0.72–0.99)

Abbreviations: ACRIN, American College of Radiology Imaging Network; LSS, Lung Screening Study.

^aRobust 95% CIs were estimated by repeating the analyses on 200 bootstrapped samples.

^bThe estimated effect in the original cohort was transported/generalized to the target cohort controlling for age, sex, race/ethnicity, education, marital status, smoking, BMI, and the recruitment arm of NLST (LSS or ACRIN).