Table 2.

Composition ratio and clinical data of patients with different pathological types in the training and validation sets.

Set	Number of cases	Age (years)	Sex		Smoking	Clinical staging				Tumor maximum diameter (cm)	Pathological type
			M	F		I	II	III	IV		Small cell lung cancer	Squamous cell carcinoma	Adenocarcinoma	Large cell lung cancer
Training set	327	62.2 ± 9.60	232	95	223	12	112	95	108	4.77 ± 2.42	141	70	70	46
Validation set	141	61.5 ± 9.33	108	33	97	6	45	46	44	4.80 ± 2.53	61	30	30	20
t or χ2		0.730	1.581*		0.016	0.766*				0.114			0.003*
p-value		0.466	0.209		0.898	0.858				0.909			1

^*χ²-value (continuous variables were analyzed by the t-test and categorical variables were analyzed by the chi-square test).