Table 1.
Distributions of epidemiological and follow-up characteristics between current smokers and current non-smokers before and after matching
| Unmatched participants | Matched participants | |||||||
|---|---|---|---|---|---|---|---|---|
| Characteristics | Current smokers (N=20) n (%) | Current non-smokers (N=335) n (%) | SMD | p* | Current smokers (N=20) n (%) | Current non-smokers (N=60) n (%) | SMD | p* |
| Age (years) | ||||||||
| Mean ± SD | 34.40 ± 10.35 | 44.7 ± 13.28 | -0.87 | 0.016 | 34.40 ± 10.35 | 34.40 ± 9.62 | 0.00 | 0.719 |
| ≤35 | 13 (65.0) | 103 (30.7) | 0.73 | 0.002 | 13 (65.0) | 41 (68.3) | -0.07 | 0.783 |
| >35 | 7 (35.0) | 232 (69.3) | 7 (35.0) | 19 (31.7) | ||||
| Marital status | ||||||||
| Single, never married | 8 (40.0) | 46 (13.7) | 0.62 | 0.020 | 8 (40.0) | 24 (40.0) | 0.00 | 1.000 |
| Married without child | 0 | 21 (6.3) | -0.37 | 0 | 0 | |||
| Married with children | 11 (55.0) | 256 (76.4) | -0.46 | 11 (55.0) | 33 (55.0) | 0.00 | ||
| Divorced | 1 (5.0) | 12 (3.6) | 0.07 | 1 (5.0) | 3 (5.0) | 0.00 | ||
| Residence | ||||||||
| Rural | 8 (40.0) | 85 (25.4) | 0.32 | 0.148 | 8 (40.0) | 20 (33.3) | 0.14 | 0.588 |
| Urban | 12 (60.0) | 250 (74.6) | 12 (60.0) | 40 (66.7) | ||||
| Education level | ||||||||
| ≤High school | 9 (45.0) | 24 (7.2) | 0.95 | 0.000 | 9 (45.0) | 18 (30.0) | 0.31 | 0.431 |
| Some college/ vocational | 5 (25.0) | 217 (64.8) | -0.87 | 5 (25.0) | 16 (26.7) | -0.04 | ||
| ≥College | 6 (30.0) | 94 (28.0) | 0.04 | 6 (30.0) | 26 (43.3) | -0.28 | ||
| Sexual life during follow-up | ||||||||
| Active | 16 (80.0) | 213 (63.6) | 0.37 | 0.136 | 16 (80.0) | 48 (80.0) | 0.00 | 1.000 |
| Never | 4 (20.0) | 122 (36.4) | 4 (20.0) | 12 (20.0) | ||||
| HPV infection status | ||||||||
| Multiple | 13 (65.0) | 148 (44.2) | 0.43 | 0.069 | 13 (65.0) | 23 (38.3) | 0.55 | 0.038 |
| Single | 7 (35.0) | 187 (55.8) | 7 (35.0) | 37 (61.7) | ||||
| History of STD | ||||||||
| Yes | 4 (20.0) | 14 (4.2) | 0.50 | 0.009 | 4 (20.0) | 9 (15.0) | 0.13 | 0.861 |
| Never | 16 (80.0) | 321 (95.8) | 16 (80.0) | 51 (85.0) | ||||
| Age at first intercourse (years) | ||||||||
| ≤20 | 11 (55.0) | 96 (28.7) | 0.55 | 0.013 | 11 (55.0) | 26 (43.3) | 0.24 | 0.365 |
| >20 | 9 (45.0) | 239 (71.3) | 9 (45.0) | 34 (56.7) | ||||
| Number of lifetime sexual partners | ||||||||
| ≤3 | 13 (65.0) | 302 (90.1) | -0.63 | 0.002 | 13 (65.0) | 48 (80.0) | -0.34 | 0.288 |
| >3 | 7 (35.0) | 33 (9.9) | 7 (35.0) | 12 (20.0) | ||||
| HPV vaccination | ||||||||
| Has been vaccinated | 1 (5.0) | 34 (10.1) | -0.19 | 0.716 | 1 (5.0) | 10 (16.7) | -0.38 | 0.349 |
| Never | 19 (95.0) | 301 (89.9) | 19 (95.0) | 50 (83.3) | ||||
*
Categorical and continuous variables were analyzed by chi-squared test and t-test, respectively. Statistical significance at p<0.05.
HPV: human papillomavirus. STD: sexually transmitted diseases. SMD: standardized mean difference.