Table 4:

Comparison of smoking characteristics of cases over and under 65 yr old

Variable	Mean ± Standard deviation	P
Age of Initiation to Smoking (yr)
60–64 age	18.85±5.91	0.002
65 age ≥	20.42±8.21
Smoking amount (Pack-year)
60–64 age	47.51±24.30	0.007
65 age ≥	52.08±25.81
Fagerstrom Nicotine Addiction Score
60–64 age	6.32±2.21	0.007
65 age ≥	5.90±2.40