Table 1.

Demographic characteristics of case-control study population

Characteristics	Controls	Cases	p-value
1. Age	n = 407	n = 407
Median age	60.8	60.8
Range	30 – 84	30 – 78
2. Gender, n, (%)	n = 407, (%)	n = 407, (%)
Male	302, (74.2)	303, (74.5)	0.94
Female	105, (25.8)	104, (25.6)
3. Smoking status, n, (%)	n = 309, (%)	n = 396, (%)
Non-smoker	162, (52.4)	108, (27.3)	<0.0001
Smoker	147, (47.6)	288, (72.7)
4. Drinking status, n, (%)	n = 224, (%)	n = 310, (%)
Non-drinker	78, (34.8)	118, (38.1)	0.44
Drinker	146, (65.2)	192, (61.9)
5. Histological cell type, n, (%)		N = 388, (%)
Adenocarcinoma		157, (40.5)
Squamous cell		123, (31.7)
Small cell		79, (20.4)
Other carcinomaa		29, (7.5)

^a Large cell, mixed cell carcinomas or undifferentiated carcinoma