Table 1

Participant characteristics by sex

General n=1257Men n=611Women n=646
Freq. (%)Freq. (%)Freq. (%)
Age (years)
 ≤12177 (14.6)103 (17.4)74 (12.0)*
 13303 (25.1)149 (25.2)154 (24.9)
 14270 (22.3)140 (23.7)130 (21.0)
 15303 (25.1)136 (23.0)167 (27.0)
 ≥16156 (12.9)63 (10.7)93 (15.1)
School grade
 Seventh grade407 (32.5)210 (34.5)197 (30.5)*
 Eighth grade263 (21.0)132 (21.7)131 (20.3)
 Ninth grade377 (30.1)185 (30.4)192 (29.8)
 First high school206 (16.4)81 (13.3)125 (19.4)
Smoked in the past 30 days?
 No994 (79.1)478 (78.2)516 (79.9)
 Yes263 (20.9)133 (21.8)130 (20.1)
Number of cigarettes per day
 ≤1 cigarette193 (73.4)91 (68.4)102 (78.5)
 2–5 cigarettes57 (21.7)32 (24.1)25 (19.2)
 6 or more cigarettes13 (4.9)10 (7.5)3 (2.3)
Smoking days over the past 30 days
 1–2 days134 (51)66 (49.6)68 (52.3)
 3–5 days52 (19.8)30 (22.6)22 (16.9)
 6–9 days29 (11.0)11 (8.3)18 (13.8)
 10–19 days19 (7.2)11 (8.3)8 (6.2)
 20–29 days12 (4.6)4 (3.0)8 (6.2)
 Daily17 (6.5)11 (8.3)6 (4.6)
  • Cuernavaca and Mexico City, 2011.