Characteristics of included studies for direct meta-analysis.

a<p>Exon of EGFR mutation means either exon 19 deletion or exon 21 L858R mutation.</p>b<p>HR_19/21 of TKI represents HR_{19 exon deletion/exon 21 L858R mutation} in TKI therapy cohort.</p>c<p>We considered time to progression (TTP) as PFS in studies of Asahina H and Jackman DM.</p>d<p>We considered <i>P</i>-value as 0.05 in Lu RL's study to calculate the HR_19/21 of TKI for PFS and its 95% CI.</p><p>Abbreviations: CI = confidence interval; EGFR = epidermal growth factor receptor; HR = Hazard ratio; NA = not available; PFS = progression-free survival; TKI = tyrosine kinase inhibitor.</p><p>Characteristics of included studies for direct meta-analysis.