Table 1. The baseline data of enrolled patients.

Characteristics	Traditional aspirator	New aspirator	P
Sex			0.878
Male	133	118
Female	117	136
Age (year), median [range]	64.26 [37–83]	63.53 [34–82]	0.372
Pathological pattern			0.704
Adenocarcinoma	136	147
Squamous cell carcinomas	105	95
Others	9	12
Tumor location			0.501
Right superior lobe	36	54
Right middle lobe	11	17
Right inferior lobe	76	62
Left superior lobe	56	58
Left inferior lobe	71	63
Number of harvested lymph nodes
No. 2/4R	5.70	5.97	0.578
No. 7R	3.83	3.72	0.393
No. 7L	3.64	3.78	0.311