Table 1.
Demographic findings of study population by safety helmet groups.
| Characteristics | Total | Safety Helmet | No Safety Helmet | p-Value | |||
|---|---|---|---|---|---|---|---|
| N | % | n | % | n | % | ||
| Total | 1298 | 100.0 | 584 | 714 | |||
| Patient characteristics | |||||||
| Age, year | 0.578 | ||||||
| 18–29 | 77 | 5.9 | 35 | 6.0 | 42 | 5.9 | |
| 30–49 | 589 | 45.4 | 272 | 46.6 | 317 | 44.4 | |
| 50–64 | 548 | 42.2 | 245 | 42.0 | 303 | 42.4 | |
| 65 and over | 84 | 6.5 | 32 | 5.5 | 52 | 7.3 | |
| Median (IQR) | 49 (41–56) | 49 (41–55) | 49 (41–56) | 0.055 | |||
| Gender | <0.0001 | ||||||
| Male | 1207 | 93.0 | 569 | 97.4 | 638 | 89.4 | |
| Female | 91 | 7.0 | 15 | 2.6 | 76 | 10.6 | |
| Occupation | <0.0001 | ||||||
| Managers | 14 | 1.1 | 7 | 1.2 | 7 | 1.0 | |
| Professionals | 23 | 1.8 | 6 | 1.0 | 17 | 2.4 | |
| Technicians and associate professionals | 174 | 13.4 | 106 | 18.2 | 68 | 9.5 | |
| Clerical support workers | 22 | 1.7 | 4 | 0.7 | 18 | 2.5 | |
| Service and sales workers | 74 | 5.7 | 8 | 1.4 | 66 | 9.2 | |
| Skilled agricultural, forestry and fishery workers | 84 | 6.5 | 7 | 1.2 | 77 | 10.8 | |
| Craft and related trades workers | 378 | 29.1 | 211 | 36.1 | 167 | 23.4 | |
| Plant and machine operators and assemblers | 107 | 8.2 | 30 | 5.1 | 77 | 10.8 | |
| Elementary occupations | 387 | 29.8 | 195 | 33.4 | 192 | 26.9 | |
| Other | 35 | 2.7 | 10 | 1.7 | 25 | 3.5 | |
| Educational level | 0.001 | ||||||
| Middle school or below | 389 | 30.0 | 177 | 30.3 | 212 | 29.7 | |
| High school | 596 | 45.9 | 296 | 50.7 | 300 | 42.0 | |
| College or above | 179 | 13.8 | 70 | 12.0 | 109 | 15.3 | |
| Unknown | 134 | 10.3 | 41 | 7.0 | 93 | 13.0 | |
| Annual income, USD | 0.001 | ||||||
| 0–30,000 | 631 | 48.6 | 291 | 49.8 | 340 | 47.6 | |
| Over 30,000 | 324 | 25.0 | 169 | 28.9 | 155 | 21.7 | |
| Unknown | 343 | 26.4 | 124 | 21.2 | 219 | 30.7 | |
| Occupation and workplace information | |||||||
| Type of employment | <0.0001 | ||||||
| Contracted worker | 652 | 50.2 | 266 | 45.5 | 386 | 54.1 | |
| Daily worker | 573 | 44.1 | 296 | 50.7 | 277 | 38.8 | |
| Other | 73 | 5.6 | 22 | 3.8 | 51 | 7.1 | |
| Working type | <0.0001 | ||||||
| Lone work | 402 | 31.0 | 118 | 20.2 | 284 | 39.8 | |
| Cooperative work | 896 | 69.0 | 466 | 79.8 | 430 | 60.2 | |
| Safety education enrollment | <0.0001 | ||||||
| Yes | 680 | 52.4 | 429 | 73.5 | 251 | 35.2 | |
| No | 543 | 41.8 | 138 | 23.6 | 405 | 56.7 | |
| Unknown | 75 | 5.8 | 17 | 2.9 | 58 | 8.1 | |
| Construction-related work | <0.0001 | ||||||
| Yes | 383 | 29.5 | 254 | 43.5 | 129 | 18.1 | |
| Injury characteristics | |||||||
| Height of fall injury, meter | <0.0001 | ||||||
| 0–2 | 370 | 28.5 | 116 | 19.9 | 254 | 35.6 | |
| 2–4 | 595 | 45.8 | 275 | 47.1 | 320 | 44.8 | |
| 4–6 | 192 | 14.8 | 100 | 17.1 | 92 | 12.9 | |
| Over 6 | 141 | 10.9 | 93 | 8.2 | 48 | 6.7 | |
| Median (IQR) | 2.2 (1.5–4.0) | 3.0 (2.0–4.0) | 2.0 (1.5–3.0) | <0.0001 | |||
| Time of injury | <0.0001 | ||||||
| Scheduled job | 1200 | 92.4 | 550 | 94.2 | 650 | 91.0 | |
| Extended/holiday work | 70 | 5.4 | 33 | 5.7 | 37 | 5.2 | |
| Other | 28 | 2.2 | 1 | 0.2 | 27 | 3.8 | |
| Place of injury | <0.0001 | ||||||
| Industrial or construction area | 816 | 62.9 | 450 | 77.1 | 366 | 51.3 | |
| Farm or other place of primary production | 139 | 10.7 | 46 | 7.9 | 93 | 13.0 | |
| Transport area (road) | 70 | 5.4 | 20 | 3.4 | 50 | 7.0 | |
| Other public area | 166 | 12.8 | 26 | 4.5 | 140 | 19.6 | |
| Home and residential institution | 107 | 8.2 | 42 | 7.2 | 65 | 9.1 | |
| Cause of the incident | <0.0001 | ||||||
| Fall from step or ladder | 393 | 30.3 | 166 | 28.4 | 227 | 31.8 | |
| Fall from existing floor openings | 67 | 5.2 | 32 | 5.5 | 35 | 4.9 | |
| Fall from a stack of luggage or payload | 93 | 7.2 | 37 | 6.3 | 56 | 7.8 | |
| Fall from roof | 78 | 6.0 | 26 | 4.5 | 52 | 7.3 | |
| Fall from scaffolding or staging | 174 | 13.4 | 111 | 19.0 | 63 | 8.8 | |
| Fall from building girders or other structural steel | 210 | 16.2 | 142 | 24.3 | 68 | 9.5 | |
| Fall from nonmoving vehicle or machine equipment | 208 | 16.0 | 61 | 10.4 | 147 | 20.6 | |
| Other | 75 | 5.8 | 9 | 1.5 | 66 | 9.2 | |
| Clinical outcomes | |||||||
| Mode of transportation | 0.048 | ||||||
| EMS use | 888 | 68.4 | 416 | 71.2 | 472 | 66.1 | |
| Head injury | |||||||
| Head injury (S06.0–S06.9) | 174 | 13.4 | 67 | 11.5 | 107 | 15.0 | 0.065 |
| Intracranial injury (S06.1–S06.9) | 89 | 6.9 | 27 | 4.6 | 62 | 8.7 | 0.004 |
| Anatomical classification of injury | |||||||
| Head, face, neck | 597 | 46.0 | 236 | 40.4 | 361 | 50.6 | <0.0001 |
| Thorax | 285 | 22.0 | 132 | 22.6 | 153 | 21.4 | 0.611 |
| Abdomen | 325 | 25.0 | 164 | 28.1 | 161 | 22.5 | 0.022 |
| Extremity | 640 | 49.3 | 287 | 49.1 | 353 | 49.4 | 0.916 |
| External and other | 112 | 8.6 | 78 | 13.4 | 34 | 4.8 | <0.0001 |
| Multiple injury | 0.038 | ||||||
| More than 2 anatomical region | 513 | 39.5 | 249 | 42.6 | 264 | 37.0 | |
| Operation | 0.047 | ||||||
| Yes | 343 | 26.4 | 170 | 29.1 | 173 | 24.2 | |
| ED disposition | 0.008 | ||||||
| Discharge | 409 | 31.5 | 159 | 27.2 | 250 | 35.0 | |
| Transfer to other hospital | 131 | 10.1 | 70 | 12.0 | 61 | 8.5 | |
| Admission | 739 | 56.9 | 344 | 58.9 | 395 | 55.3 | |
| Death | 19 | 1.5 | 11 | 1.9 | 8 | 1.1 | |
| In-hospital mortality | |||||||
| Total | 39 | 3.0 | 18 | 3.1 | 21 | 2.9 | 0.882 |
| In ED | 19 | 1.5 | 11 | 1.9 | 8 | 1.1 | |
| In Ward or ICU | 20 | 2.7 | 7 | 2.0 | 13 | 3.3 | |
| Expected days away from work | 0.001 | ||||||
| Median (IQR) | 21 (7–42) | 28 (8–46) | 20 (5–40) | ||||
| Convalescence by insurance, week | <0.0001 | ||||||
| Median (IQR) | 6 (2–8) | 5 (2–8) | 6 (3–10) | ||||
IQR: interquartile range; EMS: emergency medical services; ED: emergency department; ICU: intensive care unit.