Table 1. Association Between Independent Variables and Current and Ever Tobacco Smoking Habits in the Univariate Model: The CASPIAN-IV Study.
| Variables | Current Smoker | Ever Smoker | ||||
|---|---|---|---|---|---|---|
| Yes, % (95% CI) | No, % (95% CI) | P Value | Yes, % (95% CI) | No, % (95% CI) | P Value | |
| Age, y a | 15.55 (15.28, 15.82) | 12.39 (12.33, 12.45) | < 0.001 | 15.14 (14.94, 15.34) | 12.3 (12.25, 12.36) | < 0.001 |
| Sex | < 0.001 | < 0.001 | ||||
| Boys | 3.49 (2.91, 4.18) | 96.51 (95.82, 97.09) | 7.48 (6.54, 8.54) | 92.52(91.46, 93.46) | ||
| Girls | 1.66(1.32, 2.08) | 98.34 (97.92, 98.68) | 4.19(3.6, 4.87) | 95.81(95.13, 96.4) | ||
| Residence | < 0.001 | < 0.001 | ||||
| Urban | 3.01 (2.58, 3.52) | 96.99 (96.48, 97.43) | 6.54 (5.84, 7.31) | 93.46 (92.69, 94.16) | ||
| Rural | 1.28 (0.9, 1.80) | 98.73 (98.2, 99.1) | 3.76 (2.94, 4.8) | 96.24 (95.2, 97.06) | ||
| Type of school | 0.16 | 0.18 | ||||
| Governmental | 2.5 (2.14, 2.92) | 97.5 (97.08, 97.86) | 5.75 (5.15, 6.4) | 94.25 (93.6, 94.85) | ||
| Nonprofit | 3.37 (2.32, 4.87) | 96.64 (95.13, 97.68) | 7.16 (5.29, 9.62) | 92.84 (90.38, 94.71) | ||
| Mother’s educational level | 0.15 | 0.1 | ||||
| Illiterate | 3.00 (2.28, 3.93) | 97 (96.07, 97.72) | 5.73 (4.70, 6.96) | 94.27 (93.04, 95.3) | ||
| High school | 2.57 (2.18, 3.03) | 97.43 (96.97, 97.82) | 6.06 (5.41, 6.77) | 93.94 (93.23, 94.59) | ||
| Academic | 1.8 (1.16, 2.78) | 98.2 (97.22, 98.84) | 4.37 (3.29, 5.78) | 95.63 (94.22, 96.71) | ||
| Father’s educational level | 0.004 | 0.004 | ||||
| Illiterate | 2.52 (1.76, 3.6) | 97.48 (96.41, 98.25) | 6.53 (5.3, 8.02) | 93.47 (91.98, 94.7) | ||
| High school | 2.8 (2.40, 3.26) | 97.2 (96.74, 97.6) | 6.07 (5.43, 6.78) | 93.93 (93.23, 94.57) | ||
| Academic | 1.42 (0.98, 2.06) | 98.58 (97.94, 99.02) | 4.1 (3.21, 5.22) | 95.9 (94.78, 96.79) | ||
| Maternal occupational status | 0.07 | 0.235 | ||||
| Housekeeper | 2.6 (2.23, 3.03) | 97.4 (96.98, 97.77) | 5.92 (5.32, 6.58) | 94.08 (93.42, 94.68) | ||
| Worker | 1.7 (1.08, 2.67) | 98.3 (97.33, 98.92) | 4.62 (3.47, 6.14) | 95.38 (93.86, 96.53) | ||
| Others | 3.67 (2.24, 5.96) | 96.33 (94.04, 97.76) | 6.11 (4.13, 8.97) | 93.89 (91.03, 95.88) | ||
| Father’s occupational status | 0.02 | 0.067 | ||||
| Unemployed | 2.28 (1.39, 3.74) | 97.72 (96.26, 98.61) | 5.48 (3.94, 7.57) | 94.52 (92.43, 96.06) | ||
| Worker | 2.32 (1.93, 2.79) | 97.68 (97.21, 98.07) | 5.24 (4.61, 5.94) | 94.76 (94.06, 95.39) | ||
| Farmer | 1.86 (1.25, 2.77) | 98.14 (97.23, 98.75) | 6.07 (4.71, 7.8) | 93.93 (92.2, 95.29) | ||
| Self-employed | 3.06 (2.54, 3.69) | 96.94 (96.31, 97.46) | 6.46 (5.63, 7.40) | 93.54 (92.6, 94.37) | ||
| Living with parents | 0.19 | 0.003 | ||||
| None | 2.19 (0.826, 5.66) | 97.81 (94.34, 99.17) | 6.01 (3.36, 10.54) | 93.99 (89.46, 96.64) | ||
| One parent | 3.61 (2.41, 5.38) | 96.39 (94.62, 97.59) | 9.03 (6.94, 11.67) | 90.97 (88.33, 93.06) | ||
| Both parents | 2.54 (2.19, 2.94) | 97.46 (97.06, 97.81) | 5.7 (5.13, 6.33) | 94.3 (93.67, 94.87) | ||
| Family size | 0.15 | 0.774 | ||||
| ≤ 4 | 2.39 (1.99, 2.86) | 97.61 (97.14, 98.01) | 5.78 (5.10, 6.56) | 94.22 (93.47, 94.9) | ||
| > 4 | 2.79 (2.33, 3.33) | 97.21 (96.67, 97.67) | 5.9 (5.19, 6.71) | 94.1 (93.29, 94.81) | ||
| Days spent with friends per week | < 0.001 | < 0.001 | ||||
| No days | 1.66 (1.32, 2.08) | 98.34 (97.92, 98.68) | 4.27 (3.66, 4.97) | 95.73 (95.03, 96.34) | ||
| 1 - 3 days | 2.83 (2.33, 3.42) | 97.17 (96.58, 97.67) | 6.41 (5.64, 7.27) | 93.59 (92.73, 94.36) | ||
| >3 days | 4.48 (3.58, 5.59) | 95.52 (94.41, 96.42) | 8.82 (7.47, 10.37) | 91.18 (89.63, 92.53) | ||
| Hookah smoking by father | < 0.001 | <0.001 | ||||
| Yes | 8.12 (6.51, 10.1) | 91.88 (89.9, 93.49) | 12.74 (10.65, 15.17) | 87.26 (84.83, 89.35) | ||
| No | 2.14 (1.81, 2.52) | 97.86 (97.48, 98.19) | 5.31 (4.75, 5.92) | 94.69 (94.08, 95.25) | ||
| Hookah smoking by mother | < 0.001 | < 0.001 | ||||
| Yes | 5.73 (4.01, 8.12) | 94.27 (91.88, 95.99) | 10.17 (7.812, 13.13) | 89.83 (86.87, 92.19) | ||
| No | 2.45 (2.118, 2.86) | 97.55 (97.14, 97.89) | 5.68 (5.11, 6.32) | 94.32 (93.68, 94.89) | ||
| Hookah smoking by sister(s) or brother(s) | < 0.001 | < 0.001 | ||||
| Yes | 13.73 (11.09, 16.88) | 86.27 (83.12, 88.91) | 23.77 (20.11, 27.86) | 76.23 (72.14, 79.89) | ||
| No | 2.11 (1.8, 2.47) | 97.89 (97.53, 98.2) | 5.1 (4.58, 5.67) | 94.9 (94.33, 95.42) | ||
| Cigarette smoking by father | < 0.001 | < 0.001 | ||||
| Yes | 4.24 (3.51, 5.11) | 95.76 (94.89, 96.49) | 8.2 (5.31, 6.51) | 91.8 (90.56, 92.89) | ||
| No | 2.08 (1.76, 2.47) | 97.92 (97.53, 98.24) | 5.14 (4.59, 5.76) | 94.86 (94.24, 95.41) | ||
| Cigarette smoking by mother | 0.10 | 0.003 | ||||
| Yes | 5.71 (2.153, 14.3) | 94.29 (85.7, 97.85) | 14.29 (7.866, 24.55) | 85.71 (75.45, 92.13) | ||
| No | 2.59 (2.24, 3.0) | 97.41 (97, 97.76) | 5.84 (5.27, 6.48) | 94.16 (93.52, 94.73) | ||
| Cigarette smoking by sister(s) or brother(s) | 0.009 | < 0.001 | ||||
| Yes | 5.47 (3.07, 9.57) | 94.53 (90.43, 96.93) | 12.94 (9.06, 18.14) | 87.06 (81.86, 90.94) | ||
| No | 2.56 (2.21, 2.96) | 97.44 (97.04, 97.79) | 5.78 (5.21, 6.41) | 94.22 (93.59, 94.79) | ||
| Passive cigarette smoke exposure | < 0.001 | < 0.001 | ||||
| Yes | 8.34 (7.36, 9.43) | 91.66 (90.57, 92.64) | 8.34 (7.36, 9.43) | 91.66 (90.57, 92.64) | ||
| No | 4.58 (4.04, 5.18) | 95.42 (94.82, 95.96) | 4.58 (4.04, 5.18) | 95.42 (94.82, 95.96) | ||
| Physical activity | 0.02 | < 0.001 | ||||
| Mild | 3.16 (2.59, 3.86) | 96.84 (96.14, 97.41) | 7.42 (6.44, 8.54) | 92.58 (91.46, 93.56) | ||
| Moderate | 2.2 (1.76, 2.75) | 97.8 (97.25, 98.24) | 4.97 (4.23, 5.86) | 95.03 (94.17, 95.77) | ||
| Vigorous | 2.47 (1.97, 3.09) | 97.53 (96.91, 98.03) | 5.3 (4.49, 6.26) | 94.7 (93.74, 95.52) | ||
| Screen time | < 0.001 | < 0.001 | ||||
| > 2 hours/day | 1.93 (1.64, 2.27) | 98.07 (97.73, 98.37) | 10.63 (9.209, 12.23) | 89.37 (87.77, 90.79) | ||
| < 2 hours/day | 5.53 (4.553, 6.71) | 94.47 (93.29, 95.45) | 4.79 (4.29, 5.35) | 95.21 (94.65, 95.71) | ||
| Birth order a | 2.27 (2.15, 2.39) | 2.07 (2.05, 2.09) | < 0.001 | 2.18 (2.10, 2.26) | 2.07 (2.05, 2.09) | 0.005 |
| Sleeping hours/day a | 8.7 5(8.56, 8.94) | 9.02 (9.0, 9.05) | < 0.001 | 8.80 (8.68, 8.91) | 9.03 (9.0, 9.06) | < 0.001 |
aAre presented as the mean (95% CI).