Table 1 Overview of participating skiers and non-participating controls. Individuals in the dataset divided into gender, age group, year of inclusion, family status, education level, occupational level and Charlson index. Charlson index reflects estimated survival rate in each group [45]
Variable | N | Controls | Skiers | Total | P value |
|---|---|---|---|---|---|
N = 197,684 | N = 197,685 | N = 395,369 | |||
Gender | |||||
 Woman | 395,369 | 74,899 (37.9%) | 74,897 (37.9%) | 149,796 (37.9%) | 0.9911 |
Age | 395,369 | 36.0 (29.0–46.0) | 36.0 (29.0–46.0) | 36.0 (29.0–46.0) | 0.3622 |
 Age group: | |||||
  20–30 | 395,369 | 63,238 (32.0%) | 63,238 (32.0%) | 126,476 (32.0%) | 1.001 |
  30–40 |  | 58,246 (29.5%) | 58,246 (29.5%) | 116,492 (29.5%) |  |
  40–50 |  | 45,957 (23.2%) | 45,958 (23.2%) | 91,915(23.2%) |  |
  50–100 |  | 30,243 (15.3%) | 30,243 (15.3%) | 60,486 (15.3%) |  |
Year | 395,369 | 2001 (1996–2006) | 2001 (1996–2006) | 2001 (1996–2006) | 1.002 |
 Year group: | |||||
  1991–2000 | 384,601 | 89,517 (46.6%) | 89,518 (46.6%) | 179,035 (46.6%) |  |
  2001–2005 |  | 51,752 (26.9%) | 51,752 (26.9%) | 103,504 (26.9%) |  |
  2006–2010 |  | 51,031 (26.5%) | 51,031 (26.5%) | 102,062 (26.5%) |  |
Family status: | |||||
 Cohabiter | 384,573 | 108,629 (56.5%) | 115,757 (60.2%) | 224,386 (58,3%) | < 0.0011* |
Educational level | |||||
 Primary school | 392,048 | 34,806 (17.9%) | 14,538 (7.4%) | 49,344 (12.6%) | < 0.0011* |
  High school |  | 99,936 (51.3%) | 76,635 (38.8%) | 176,571 (45.0%) |  |
  University |  | 59,986 (30.8%) | 106,147 (53.8%) | 166,133 (42.4%) |  |
Occupation level | |||||
 Employed | 378,596 | 142,020 (75.5%) | 162,849 (85.5%) | 304,869 (80.5%) | < 0.0011* |
 Unemployed |  | 43,811 (23.3%) | 25,662 (13.5%) | 69,473 (18.4%) |  |
 Retired |  | 2225 (1.2%) | 2029 (1.1%) | 4254 (1.1%) |  |
Charlson index | |||||
 0 | 2,407,956 | 112,182 (91.7%) | 111,061 (93.8%) | 223,243 (92.7%) | < 0.0011* |
 1 |  | 9030 (7.4%) | 7018 (5.9%) | 16,048 (6.7%) |  |
 2 |  | 839 (0.7%) | 322 (0.3%) | 1161 (0.5%) |  |
 3 |  | 197 (0.2%) | 53 (0.0%) | 250 (0.1%) |  |
 4 |  | 43 (0.0%) | 4 (0.0%) | 47 (0.0%) |  |
 5 |  | 19 (0.0%) | 2 (0.0%) | 21 (0.0%) |  |
 6 |  | 17 (0.0%) | 4 (0.0%) | 21 (0.0%) |  |
 7 |  | 2 (0.0%) | 0 (0.0%) | 2 (0.0%) |  |
 8 |  | 3 (0.0%) | 0 (0.0%) | 3 (0.0%) |  |
 9 |  | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) |  |