## 4 Discussion
### Individual Factors  
A lower age (OR 0.966) was associated with a decreasing risk of falling by 3% when adjusted for other factors although the simple analysis found a lower mean age in skiers with falls (Table 1). This result of the multiple analysis (Table 2) seems to be in contrast to the earlier results by [PERSON] et al. [6] and [PERSON] et al. [7] who, however, also included child and adolescent skiers and snowboarders (Range: 6-80 years) while we only asked adult skiers >17 years (Range: 18-80 years). In addition, the snowboard population is generally younger than the skier population and younger people are more prone to use fun or snow parks where they can jump over a variety of man-made features potentially increasing risk of falling [21]. In addition, aging is associated with a progressive loss of neuromuscular function [22; 23] which in general is an important function in keeping balance and in steering and turning skis on slopes.  
Results of the logistic regression analysis revealed that a high fitness level (OR 0.251) decreased the risk of falling by 75%. A higher fitness level might also be associated with younger age [22; 23] and therefore could prevent falls. It is widely recommended that proper conditioning prior to the skiing season would be beneficial for injury prevention as increased muscular strength would help to splint the joints during a fall [24].  
The proportion of less skilled skiers in the univariate comparison was higher in skiers with falls compared to those without a fall (50 vs. 13%). The result of the logistic regression also revealed a lower skill level associated with about a 2.8-fold elevated risk for falling  
\begin{table}
\begin{tabular}{c c c c c c c} \hline
**Risk Factor** & **Coefficient** & **Standard Error** & **df** & \(p\) & **Odds Ratio** & **95\% CI** \\ \hline Age & \(-\)0.035 & 0.008 & 1 & \(<\)0.001 & 0.966 & 0.951–0.981 \\ fitness level & & & & & & \\ Very good/good & \(-\)1.380 & 0.412 & 1 & 0.001 & 0.251 & 0.112–0.564 \\ Skill level & & & & & & \\ Less skilled & 1.024 & 0.260 & 1 & \(<\)0.001 & 2.785 & 1.672–4.638 \\ Preferred skiing speed & & & & & & \\ Moderate & \(-\)0.833 & 0.341 & 1 & 0.014 & 0.435 & 0.223–0.848 \\ Relativized ski length (\%) & \(-\)0.104 & 0.030 & 1 & 0.001 & 0.901 & 0.850–0.956 \\ Sidecut radius (m) & 0.088 & 0.043 & 1 & 0.041 & 1.092 & 1.004–1.188 \\ Snow condition & & & & & & \\ Fresh snow & \(-\)0.982 & 0.477 & 1 & 0.039 & 0.375 & 0.147–0.954 \\ Snow condition & & & & & & \\ Grippy & \(-\)0.797 & 0.249 & 1 & 0.001 & 0.451 & 0.277–0.735 \\ Slope difficulty & & & & & & \\ Easy & 1.095 & 0.415 & 1 & 0.008 & 2.991 & 1.325–6.748 \\ Intercept & 13.081 & 3.767 & 1 & 0.001 & 479,772.284 & \\ \hline \end{tabular} Nagelkerkes R-Square = 0.287, classification table—overall percentage = 88.4%.  
\end{table}
Table 2: Significant results of adjusted odds ratios of individual, equipment-related and environmental factors associated with risk of falls.  
(OR 2.785). Well in accordance, [PERSON] et al. [6] and [PERSON] et al. [7] reported lower skiing skills as predictive for falls. In general, a lower skill level seems to be also associated with a higher overall injury risk in recreational alpine skiing [25; 26].  
Results of the regression analysis revealed for the factor'moderate speed' an odds ratio of 0.435 which corresponds to a decreased risk for falling by about 56%. One can assume that a moderate skiing speed is connected to the individual skill level of the skier for not skiing beyond individual boundaries.