| Background variable | Hazard ratio (95% CI) for cruciate ligament injury | |||
| Boys | Girls | |||
| Urbanisation level of residence | ||||
| Capital area (Helsinki and adjoining towns) | 1 | 1 | ||
| Large town (population >100 000) | 1.0 (0.5 to 2.0) | 0.7 (0.2 to 1.8) | ||
| Small town | 1.1 (0.7 to 1.9) | 0.7 (0.4 to 1.4) | ||
| Village | 0.9 (0.5 to 1.5) | 0.5 (0.2 to 1.0) | ||
| Sparsely populated rural municipality | 0.7 (0.4 to 1.3) | 0.5 (0.2 to 1.3) | ||
| Education of father or other parent/guardian | ||||
| High | 1 | 1 | ||
| Middle | 1.0 (0.6 to 1.7) | 1.4 (0.7 to 2.7) | ||
| Low | 0.9 (0.6 to 1.4) | 0.7 (0.4 to 1.3) | ||
| Family composition | ||||
| Nuclear (both parents were adolescent’s own) | 1 | 1 | ||
| Non-nuclear | 1.3 (0.9 to 1.8) | 0.9 (0.5 to 1.5) | ||
| Perceived health status | ||||
| Excellent | 1 | 1 | ||
| Good | 0.6 (0.5 to 0.8) | 0.6 (0.4 to 1.0) | ||
| Poor | 0.4 (0.3 to 0.7) | 0.5 (0.2 to 0.9) | ||
| Chronic disease or disability | ||||
| No | 1 | 1 | ||
| Yes | 1.0 (0.6 to 1.7) | 1.4 (0.7 to 2.7) | ||
| Number of stress symptoms weekly | ||||
| 0 | 1 | 1 | ||
| 1 | 1.3 (1.0 to 1.9) | 1.0 (0.6 to 1.8) | ||
| 2 | 0.9 (0.5 to 1.4) | 0.6 (0.3 to 1.2) | ||
| 3+ | 0.8 (0.5 to 1.3) | 1.0 (0.6 to 1.8) | ||
| Overweight | ||||
| No | 1 | 1 | ||
| Yes | 1.1 (0.8 to 1.7) | 1.5 (0.8 to 3.1) | ||
| Smoking | ||||
| Not daily | 1 | 1 | ||
| Daily | 0.9 (0.7 to 1.3) | 0.6 (0.3 to 1.2) | ||
| Drinking style | ||||
| Abstinence | 1 | 1 | ||
| Occasional drinking | 0.7 (0.5 to 1.0) | 1.5 (0.7 to 3.4) | ||
| Recurrent drinking | 0.8 (0.6 to 1.1) | 1.7 (0.8 to 3.7) | ||
| Recurring drunkenness | 0.6 (0.4 to 1.0) | 1.5 (0.6 to 3.7) | ||
| Frequency of participation in sports clubs | ||||
| Never | 1 | 1 | ||
| 2–3 times a week or less | 2.1 (1.5 to 3.0) | 2.1 (1.2 to 3.6) | ||
| 4–5 times a week or more | 4.1 (3.2 to 6.4) | 11.5 (6.7 to 19.8) | ||
| Frequency of other physical activity | ||||
| Never | 1 | 1 | ||
| 2–3 times a week or less | 1.8 (0.7 to 4.9) | 0.9 (0.2 to 3.5) | ||
| 4–5 times a week or more | 2.2 (0.8 to 6.0) | 1.5 (0.4 to 6.3) | ||
| Timing of puberty | ||||
| Early | 1 | 1 | ||
| Normal | 1.1 (0.8 to 1.5) | 1.3 (0.7 to 2.7) | ||
| Late | 0.9 (0.6 to 1.3) | 1.4 (0.6 to 3.2) | ||
*Estimated by separate Cox regression models.
The hazard ratios are age-adjusted.