Most of the ambulatory and stationary treated patients in winter resorts in Switzerland have head and extremity injuries that are mostly the result of ski/snowboard accidents (85%). An orthopedic dataset including trauma and non-trauma related diagnoses were used to evaluate to which extent these cases stress the overall hospital service utilization in such areas. We decided to include non-trauma (such as degenerative diagnosis) related diagnosis because the tourist population may as well contain (older) people with degenerative conditions. These tourists possibly will be at higher risk of having a winter condition related accident in winter sport than in flat land areas. An even better dataset would have included all hospitalized patients, but a dataset including all necessary variables was not available at the time of analysis.
Using the method of small area analysis, Switzerland can be divided into 85 orthopedic hospital service areas (HSAo), of which 24 can be defined as a winter sport area (WSA) based upon an accommodation pattern of the guest beds above 1000 meters altitude. Seventeen of the HSAo defined as WSA show a seasonal winter-summer pattern (SeH) in hospital admission rates, with single HSAo showing up to 7–9 times higher admission rates in the winter season than in the intermediate season. The remaining 7 WSA HSAo do not show a seasonal hospitalization pattern. Whereas WSA HSAo showing a seasonal admission pattern all contain large nationally and internationally recognized winter sport resorts, resorts in WSA HSAo without a seasonal hospitalization pattern are, with one exception, only nationally known. None of the HSAo with guest beds above 1000 meters that have a summer season accommodation pattern show a seasonal pattern in hospital admission rates.
HSAo defined as WSA differ in several ways: injuries of nonlocal residents can be treated locally, resulting in a seasonal pattern of hospital admissions; or, nonlocal residents can be treated outside their HSAo of injury because, for example, the necessary health service is not available there, thus leaving too few nonlocal residents treated locally to produce a seasonal pattern. In addition, more geographically isolated areas, such as found in Graubünden or Valais, have to treat their patients locally, whereas WSA HSAo adjacent to RegA HSAo may transfer emergency cases to those regular HSAo, where they dissolve in the mass. Also, larger, international ski resorts may produce more emergencies (when compared to smaller, more local resorts) that involve foreigners, who may be less easily transferred elsewhere.
As an alternative hypothesis, one may postulate that WSA HSAo that do not show a seasonal hospitalization pattern provide better injury prevention measures, resulting in fewer injuries during the winter than in SeH. Although this hypothesis cannot be verified with our data, it would be of great interest to investigate the link between admission rates and the number of people practicing leisure sports during a given period.
Nonlocal resident admissions in WSA, especially during the winter months, are significantly younger than admitted local residents and their average length of stay is shorter. This supports the hypothesis that winter leisure sport tourism causes the mean observed seasonal peak in hospital admission rates.
In general, emergency cases stress the health care system more in WSA than in RegA. With large admission fluctuations over the year, these cases require tremendous flexibility in resource planning in WSA (especially in SeH within WSA). As nonlocal residents are the main originators of the emergency admissions, in order to avoid an imbalance between demand and supply hospital bed and staff planning cannot be based on the local population size alone. The provision of enough beds in winter may mean a half empty hospital and suspension of staff during the intermediate season, which could have substantial financial and employment consequences for mountain regions with mostly lower than average population densities and job opportunities.
This study has some limitations. The definition of winter sport areas is based on accommodation nights in beds above 1000 meters altitude offered by hotels or guest houses for only one year (2003); no data for other years are available. In addition, accommodation in private condos and chalets was not taken into account. An alternative definition criterion could have been the number of ski lifts or length of downhill slopes. A database containing the exact number of ski lifts could not be compiled that suits this study, and the length of slopes was not taken into consideration because slopes may cross HSAo borders. As the correlation between guest bed accommodation and hospitalization rates is substantial and significant, and the defined area corresponds well with the location of known winter sport resorts, the definition of the winter sport area is considered appropriate.
We chose to analyze and average values of HSAo according to an external definition of winter sport and regular areas in order to prevent biases. Alternatively, HSAo could have been grouped and analyzed by individual hospitalization rate patterns (SeH and CoH). This would have increased the magnitude of the observed seasonal patterns in hospitalization rates, but would have excluded areas with known winter sport resorts from being analyzed as WSA. The chosen option allows the observation that not all WSA HSAo have hospitalization rates that show "winter sport" seasonality.
Calculated admission rates relate to the local HSAo population size, not the effective, temporary population size that varies by season. This might distort the results as HSAo with a low population size may have a greater relative tourist load than HSAo with higher population numbers (and vice versa), which would inflate the observed admission rates. To overcome this problem the admission index was calculated. However, this index becomes skewed when the monthly average is driven up by some extreme values for one or two (winter) months, as seen for some WSA HSAo. As Table 1 and Figure 2 show, the hospital admission index for nonlocal residents is below 1 during the summer in WSA and above 1 in RegA HSAo, although the admission rate numbers in WSA are still higher than in Reg HSAo. While these considerations are of great importance when it comes to hospital planning or injury prevention, the given evaluation does not resolve the debate on bed utilization and bed pressures.
Finally, no sex and age adjustments could be made for admission rates or length of stay because the necessary reference population for the corresponding months cannot be estimated.
The display of local and nonlocal resident admission rates in a geographic information system can be used to assist hospital planning and policymaking by highlighting areas where public health interventions can be applied. In emergency orthopedics, greater variability in bed use over the year is observed only in HSAo defined as winter sport areas. This variability is mainly caused by nonlocal residents and therefore high likely derives from tourism. The implications of our evaluation for hospital planning and health care resource allocation may be considerable. With its cantonally organized health care system , Switzerland shows great geographic and terrain-related utilization variations that make different demands upon health care not just between but within single cantons. To supply adequate hospital beds and staff throughout the year and at the same time operate cost-effectively, hospitals in HSAo located in winter sport areas may need larger subsidies.
The observation that most of the patients treated in winter resorts in Switzerland have ski/snowboard accidents  emphasizes the conclusion that ski/snowboard tourism places a high burden on the hospital organization of winter sport areas. Reducing the risk of ski/snowboard related injuries through adequate prevention programs therefore might be of great importance not only to the individual guest, but also to these regions as a whole.