Number and rate (%) of always wearing helmet among respondents who regularly use motorcycles from the 2001 and 2009 Taiwan National Health Interview Surveys
| 2001 | 2009 | p Value | |||||
|---|---|---|---|---|---|---|---|
| n | % | 95% CI | n | % | 95% CI | ||
| Total | 14 801 | 91.9 | (91.5 to 92.4) | 15 748 | 88.8 | (88.4 to 89.3) | <0.0001 |
| Sex | |||||||
| Male | 7439 | 91.5 | (90.9 to 92.1) | 7291 | 87.0 | (86.3 to 87.7) | <0.0001 |
| Female | 7362 | 92.4 | (91.8 to 93.0) | 8457 | 90.7 | (90.1 to 91.3) | <0.0001 |
| Age group (years) | |||||||
| 12–17 | 1534 | 83.9 | (82.2 to 85.6) | 1593 | 75.9 | (74.1 to 77.7) | <0.0001 |
| 18–24 | 2535 | 92.7 | (91.7 to 93.7) | 2287 | 92.1 | (91.1 to 93.2) | <0.0064 |
| 25–44 | 6691 | 93.4 | (92.8 to 93.9) | 6772 | 90.2 | (89.5 to 90.9) | <0.0001 |
| 45–64 | 4041 | 92.5 | (91.7 to 93.3) | 5096 | 90.0 | (89.2 to 90.7) | <0.0001 |
| Urbanisation level | |||||||
| Rural | 4057 | 83.7 | (82.6 to 84.7) | 3724 | 81.2 | (80.1 to 82.4) | 0.0028 |
| Suburban | 2698 | 93.6 | (92.7 to 94.5) | 2724 | 88.3 | (87.2 to 89.4) | <0.0001 |
| Urban | 4069 | 96.6 | (96.0 to 97.1) | 4187 | 93.0 | (92.2 to 93.7) | <0.0001 |
| Metropolitan | 3764 | 95.7 | (95.0 to 96.3) | 5096 | 90.5 | (89.7 to 91.3) | <0.0001 |
| SII | 0.036 | (0.033 to 0.040) | 0.027 | (0.022 to 0.031) | 0.2527 | ||
| RII | 1.732 | (1.633 to 1.836) | 1.328 | (1.267 to 1.392) | <0.0001 | ||
| Education level | |||||||
| Primary or lower | 2887 | 89.7 | (88.6 to 90.7) | 1899 | 85.7 | (84.2 to 87.1) | <0.0001 |
| Secondary | 3020 | 89.2 | (88.2 to 90.3) | 2641 | 82.5 | (81.2 to 83.8) | <0.0001 |
| High school | 5261 | 92.3 | (91.7 to 93.0) | 5425 | 88.9 | (88.1 to 89.7) | <0.0001 |
| College or higher | 3627 | 95.6 | (95.0 to 96.3) | 5777 | 92.7 | (92.0 to 93.3) | <0.0001 |
| SII | 0.019 | (0.015 to 0.024) | 0.033 | (0.027 to 0.039) | 0.0004 | ||
| RII | 1.344 | (1.253 to 1.441) | 1.403 | (1.325 to 1.486) | 0.1204 | ||
| Household monthly income (NT dollars) | |||||||
| <=29 999 | 2590 | 87.6 | (86.4 to 88.8) | 2918 | 85.8 | (84.6 to 87.0) | 0.0008 |
| 30 000–49 999 | 3563 | 91.9 | (91.0 to 92.7) | 3382 | 90.2 | (89.2 to 91.1) | <0.0001 |
| 50 000–69 999 | 3380 | 92.8 | (91.9 to 93.6) | 2819 | 89.6 | (88.5 to 90.6) | <0.0001 |
| 70 000–99 999 | 2758 | 94.2 | (93.3 to 95.0) | 2240 | 90.8 | (89.7 to 92.0) | <0.0001 |
| >=100 000 | 2383 | 93.8 | (92.9 to 94.8) | 2115 | 90.2 | (89.0 to 91.4) | <0.0001 |
| SII | 0.007 | (0.003 to 0.010) | −0.002 | (−0.006 to 0.002) | 0.0027 | ||
| RII | 1.095 | (1.045 to 1.147) | 0.987 | (0.946 to 1.028) | 0.0004 | ||
SII=slope index of inequality (similar to linear coefficient) according to linear regression model.
RII=relative index of inequality (similar to OR) according to logistic regression model.