Table 3. Baseline characteristics of 2608 people who participated in the health survey but not the face-to-face follow-up survey by response status (mail or telephone), and odds ratios and 95% confidence intervals of telephone responses according to these characteristics.
| Baseline characteristics | Telephone survey (n = 548) |
Mail survey (n = 2060) |
Adjusted ORa | (95% CI) | |
| Female (vs male) | 260 | 1269 | 0.61 | (0.45–0.81) | |
| Age category | 40–44 | 110 | 231 | 2.28 | (1.57–3.32) |
| 45–49 | 92 | 274 | 1.63 | (1.12–2.37) | |
| 50–54 | 95 | 338 | 1.32 | (0.93–1.90) | |
| 55–59 | 105 | 401 | 1.23 | (0.87–1.72) | |
| 60–64 | 77 | 380 | 1.00 | (ref) | |
| 65–69 | 69 | 436 | 0.80 | (0.55–1.16) | |
| Education, years (≤12 vs >12) | 331 | 1245 | 1.21 | (0.97–1.50) | |
| Occupational class | High | 164 | 467 | 1.00 | (ref) |
| Medium | 153 | 578 | 0.82 | (0.62–1.08) | |
| Low | 103 | 297 | 1.09 | (0.79–1.51) | |
| None | 126 | 702 | 0.73 | (0.53–0.99) | |
| Drinking status | Never | 219 | 867 | 1.00 | (ref) |
| Former | 17 | 67 | 0.85 | (0.47–1.53) | |
| 0.1–22.9 g ethanol/day | 169 | 691 | 0.79 | (0.62–1.01) | |
| 23.0–45.9 g ethanolday | 74 | 224 | 0.75 | (0.53–1.07) | |
| ≥46 g ethanol/day | 68 | 209 | 0.66 | (0.45–0.96) | |
| Smoking status | Never | 260 | 1219 | 1.00 | (ref) |
| Former | 105 | 373 | 0.98 | (0.71–1.34) | |
| Current | 183 | 468 | 1.29 | (0.97–1.70) | |
| Quartiles of PAL | Q1 (<1.402) | 143 | 588 | 1.10 | (0.82–1.47) |
| Q2 (1.402–1.449) | 136 | 519 | 1.11 | (0.84–1.48) | |
| Q3 (1.450–1.505) | 127 | 451 | 1.19 | (0.89–1.60) | |
| Q4 (≥1.506) | 127 | 463 | 1.00 | (ref) | |
| Sleeping category (hours) | <6 | 71 | 272 | 1.00 | (072–1.39) |
| ≥6 to <7 | 211 | 680 | 1.15 | (0.91–1.46) | |
| ≥7 to <8 | 179 | 718 | 1.00 | (ref) | |
| ≥8 | 85 | 389 | 0.91 | (0.67–1.25) | |
| BMI category (kg/m2) | <18.5 | 16 | 130 | 0.52 | (0.29–0.90) |
| ≥18.5 to <25 | 344 | 1409 | 1.00 | (ref) | |
| ≥25 | 187 | 518 | 1.43 | (1.15–1.79) | |
| Percieved stress | High | 179 | 613 | 1.11 | (0.83–1.50) |
| Medium | 262 | 966 | 1.16 | (0.89–1.52) | |
| Low | 107 | 479 | 1.00 | (ref) | |
| Medical history (vs no history) | Hypertension | 104 | 455 | 0.68 | (0.43–1.07) |
| Diabetes | 47 | 138 | 1.66 | (0.89–3.13) | |
| Dyslipidemia | 111 | 395 | 1.15 | (0.85–1.57) | |
| Ischemic heart disease | 13 | 62 | 0.94 | (0.50–1.79) | |
| Stroke | 10 | 40 | 1.18 | (0.56–2.47) | |
| Cancer | 23 | 114 | 0.92 | (0.57–1.50) | |
| On medication (vs no medication) | Hypertension | 89 | 374 | 1.36 | (0.84–2.24) |
| Diabetes | 30 | 95 | 0.78 | (0.36–1.66) | |
| Dyslipidemia | 50 | 209 | 0.95 | (0.61–1.47) | |
| Anti-inflammatory drugs | 29 | 94 | 1.35 | (0.85–2.13) | |
| Constipation | 29 | 149 | 0.90 | (0.58–1.40) | |
| Sleeping disorder | 22 | 115 | 0.89 | (0.53–1.47) | |
BMI, body mass index; CI, confidence interval; OR, odds ratio; PAL, physical activity level, which was calculated as total daily energy expenditure divided by basal energy expenditure and classified into quartiles.
aAdjusted for all items listed in the table.