Multivariate survey based logistic regression with helmet rental as outcome
| Predictor variable | Coefficient (log prevalence odds ratio) | Standard error of coefficient | Adjusted prevalence estimate* (95% confidence interval) |
|---|---|---|---|
| *For region, this is the estimated prevalence of helmet rental availability (in any capacity) for ski areas of size ⩽50 acres (referent category). For ski area size, this is the estimated prevalence of helmet rental availability (in any capacity) for resorts in the West (referent category). | |||
| Region | |||
| West (referent) | 1.0000 | – | 24.3 (16.6 to 34.1) |
| South | 0.2238 | 0.1690 | 28.7 (18.6 to 41.3) |
| Northeast | 0.6957 | 0.1798 | 39.2 (23.0 to 58.1) |
| Midwest | −0.7299 | 0.1947 | 13.4 (10.6 to 16.8) |
| Rocky Mountains | 0.2829 | 0.1505 | 29.9 (19.2 to 43.4) |
| Ski area size | |||
| ⩽50 acres (referent) | 1.0000 | – | 24.3 |
| (⩽20.2 hectares) | (16.6 to 34.1) | ||
| 51–150 acres | 0.5854 | 0.1724 | 36.6 |
| (20.6–60.7 hectares) | (22.0 to 54.2) | ||
| 151–500 acres | 1.5220 | 0.1891 | 59.5 |
| (61.1–202.3 hectares) | (23.7 to 68.6) | ||
| ⩾501 acres | 2.004 | 0.2151 | 70.4 |
| (⩾202.7 hectares) | (37.9 to 90.4) | ||