观察组(n = 50)控制组(n = 56)

n (%) n (%) statistic value P

25 (50)

32 (57.1)

x2 = 0.542

P = 0.462

25 (50)

24 (42.9)

年龄

62.34 ± 8.97

59.75 ± 9.81

t = 1.413

P = 0.161

有吸烟史

17 (34)

20 (35.7)

x2 = 0.034

P = 0.853

无吸烟史

33 (66)

36 (64.3)