Risk factors for injuries during travel to and from work
| Factor | Injuries (n) | Person-years | Rate/100 person-years | Adjusted rate ratio4-150 (95% CI) |
| Age group (y): | ||||
| <20 | 305 | 7084 | 4.3 | 1.00 |
| 20–24 | 1206 | 35003 | 3.5 | 0.84 (0.74 to 0.95) |
| 25–29 | 1046 | 44958 | 2.3 | 0.65 (0.57 to 0.74) |
| 30–34 | 686 | 42197 | 1.6 | 0.53 (0.46 to 0.62) |
| 35–39 | 395 | 30358 | 1.3 | 0.44 (0.38 to 0.52) |
| 40–44 | 223 | 18438 | 1.2 | 0.40 (0.33 to 0.48) |
| ⩾45 | 220 | 16183 | 1.4 | 0.43 (0.35 to 0.51) |
| χ1 2 trend=244, p<0.0001 | ||||
| Duration of employment (y): | ||||
| <1 | 463 | 11281 | 4.1 | 1.00 |
| 1–1.9 | 474 | 11947 | 4.0 | 1.00 (0.88 to 1.14) |
| 2–4.9 | 1203 | 37394 | 3.2 | 0.89 (0.80 to 0.99) |
| 5–9.9 | 964 | 52528 | 1.8 | 0.62 (0.55 to 0.70) |
| 10–14.9 | 522 | 42853 | 1.2 | 0.48 (0.42 to 0.56) |
| ⩾15 | 455 | 38218 | 1.2 | 0.43 (0.38 to 0.50) |
| χ1 2 trend=286, p<0.0001 | ||||
| Calendar period: | ||||
| 1977–80 | 1948 | 49174 | 4.0 | 1.00 |
| 1981–84 | 947 | 51965 | 1.8 | 0.54 (0.49 to 0.59) |
| 1985–88 | 775 | 50526 | 1.5 | 0.51 (0.46 to 0.56) |
| 1989–92 | 411 | 42557 | 1.0 | 0.35 (0.31 to 0.39) |
| χ1 2 trend=435, p<0.0001 | ||||
| Total | 4081 | 194222 | 2.1 | |
↵4-150 Age group and duration of employment are adjusted for calendar period and calendar period is adjusted for duration of employment.