Characteristics of 138 559 male vehicle mechanics and 1 385 590 matched male comparison workers
| Characteristics | Vehicle mechanics (n=1 38 559) | Comparators (n=1 385 590) |
| Age at cohort entry, n (%) | ||
| 10–20 years | 43 125 (31) | 428 763 (31) |
| 20–29 years | 44 769 (32) | 451 411 (33) |
| 30–39 years | 22 612 (16) | 224 091 (16) |
| 40–49 years | 13 168 (10) | 132 791 (10) |
| 50–59 years | 8881 (6) | 88 623 (6) |
| 60+ years | 6004 (4) | 59 911 (4) |
| Median age (quartiles) at study entry, years | 25 (19–37) | 24 (19–37) |
| Calendar year of first registration* as a vehicle mechanic or comparison employee, n (%) | ||
| Nationwide census November 1970 | 21 102 (15) | 211 020 (15) |
| 1980–1985 | 19 373 (14) | 193 730 (14) |
| 1986–1995 | 42 079 (30) | 420 790 (30) |
| 1996–2005 | 34 433 (25) | 344 330 (25) |
| 2006–2012 | 21 572 (16) | 215 720 (16) |
| Median follow-up time (quartiles), years | 20 (11–28) | 19 (10–28) |
| Maximum follow-up time, years | 45 | 45 |
*Calendar year periods after 1980 had different labour market registration systems. See text.