Characteristics Boys Girls Total
N % N % N %
Total 275 49.73 278 50.27 553 100.00
Chronological age (in years)            
15- 65 23.64 78 28.06 143 25.86
16- 87 31.64 90 32.37 177 32.01
17- 85 30.91 81 29.14 166 30.02
18- 38 13.82 29 10.43 67 12.12
Mean(SD) 16.37 (1.08) 16.24  (1.15) 16.31 (1.12)
School Grade            
Year One 146 53.09 154 55.4 300 54.25
Year Two 129 46.91 124 44.6 253 45.75
Parents’ marital status            
  Married 233 84.73 225 80.94 458 82.82
  Divorce or others 42 15.27 53 19.06 95 17.18
Father’s education            
  Primary school or less 58 21.09 66 23.74 124 22.42
  Middle school/technical secondary school 186 67.64 177 63.67 363 65.64
  Junior college/college and above 27 9.82 32 11.51 59 10.67
  Don’t know 4 1.45 3 1.08 7 1.27
Mother’s education            
  Primary school or less 84 30.55 91 32.73 175 31.65
  Middle school/technical secondary school 167 60.73 168 60.43 335 60.58
  Junior college/college and above 21 7.64 16 5.76 37 6.69
Don’t know 3 1.09 3 1.08 6 1.08
Family incomea            
  Below 999 RMB per month 54 19.85 58 20.86 112 20.25
  1000 to 1999 RMB per month 93 34.19 108 38.85 201 36.35
  2000 to 2999 RMB month 74 27.21 67 24.10 141 25.50
  Above 3000 RMB month 51 18.75 42 15.11 93 16.82
Intention to smoke**            
  Very unlikely 137 50.74 219 81.72 356 66.17
  Unlikely 44 16.30 19 7.09 63 11.71
  Likely 69 25.56 25 9.33 94 17.47
  Very likely 20 7.41 5 1.87 25 4.65
No. of Cigarettes smoked per daya **            
0 cigarette 141 55.29 248 92.88 389 74.52
1 cigarette 34 13.33 12 4.49 46 8.81
2 to 5 cigarettes 63 24.71 6 2.25 69 13.22
More than 5 cigarettes 17 6.67 1 0.37 18 3.45
Note: aFrequency not adding up to total due to missing data; gender difference, **: p < 0.01(χ2 test)
Table 1: Characteristics of the study sample.