Table 1. Univariate analysis of demographic and clinical characteristics affecting the median PFS in stage IV NSCLC patients with EGFR-TKI therapy.

Characteristics		No. of cases	Median PFS (months, 95% CI)	P
Overall		94	11 (10.1–11.9)	-
Gender	Male	49	12 (10.39–13.61)	0.304
	Female	45	11 (9.26–12.74)
Age (years)	≤ 60	58	12 (11.07–12.93)	0.715
	> 60	36	10 (8.92–11.09)
Smoking status	No	73	11 (10.03–11.97)	0.427
	Yes	21	10 (9.18–10.82)
Pathologic type	Adenocarcinoma	86	11 (10.03–11.97)	0.713
	Non-adenocarcinoma	8	12 (9.23–11.77)
Brain metastasis	Yes	33	11 (9.92–12.08)	0.963
	No	61	11 (9.66–12.34)
Timing of targeted therapy	First line	28	15 (7.94–22.06)	0.04
	Second or higher line	66	11 (10.14–11.86)
ECOG score	0–1	54	12 (10.29–13.71)	0
	≥ 2	40	8 (6.5–9.5)
Type of EGFR mutation (64 cases)	19del	37	13 (10.05–15.95)	0.003
	21L858R	27	9 (7.53–10.47)