Table 4.

Impact of Erlotinib versus Gefitinib on 1‐year progression‐free survival and 1‐year overall survival in the whole cohort, epidermal growth factor receptor‐tyrosine kinase inhibitor (EGFR‐TKI) responder, and three different subgroups by multivariate Cox proportional hazards regression analysis with inverse propensity score weighting adjustment

Erlotinib vs. Gefitinib	1‐year progression‐free survival			1‐year overall survival
	HR	95% CI	P value	HR	95% CI	P value
Whole cohort (n = 7222)	1.15	1.09–1.21	<0.001	1.10	1.03–1.18	0.003
EGFR‐TKI respondera , c(n = 4939)	1.11	1.03–1.17	0.006	1.08	0.98–1.18	0.122
Adherent populationb (n = 4079)	1.09	1.02–1.16	0.010	1.08	1.02–1.16	0.030
Adenocarcinomac (n = 2478)	1.35	1.24–1.47	<0.001	1.89	1.62–2.19	<0.001
Second‐line, adenocarcinomac (n = 1181)	1.39	1.22–1.59	<0.001	1.87	1.47–2.37	<0.001

Multivariate Cox regression adjusted for gender, age, disease severity (operation, cachexia, increased intracranial pressure, duration of hospitalization [days], and transfusion), comorbidities (chronic obstructive pulmonary disease, diabetes mellitus, chronic kidney disease, tuberculosis, liver cirrhosis, autoimmune disease, transplantation, AIDS, and other malignancies), EGFR‐TKI responder, and low income.

^aPatients who received epidermal growth factor receptor‐tyrosine kinase inhibitors (EGFR‐TKIs) for more than 90 days.

^bPatients with a medication possession ratio of EGFR‐TKIs ≥ 1.

^cPatients who previously received pemetrexed.