To What Extent Are Main Accident-Insurer Cases Representative of All Significantly Injured? A Swiss Monocenter Perspective.

Background and Objectives.- Even though Switzerland has a compulsory insurance system, there is a lack of detailed information on the treatment and outcome following trauma. The objective of this evaluation was to examine to what extent cases insured by the largest accident-insurer (Suva) are representative of all significantly injured. Methods.- Trauma center analysis of all ≥16 year old trauma patients with a New Injury Severity Score (NISS) ≥8, comparing the characteristics of Suva- vs non-Suva cases (chi-square; univariate explained variance R2 ; multivariate logistic regression analysis, Nagelkerke R2 ). Results.- Over 7 years, 2233 trauma patients were treated at the hospital, of whom 29.4% were Suva-insured. Compared to non-Suva-insured, Suva cases were younger (41.6 vs 64.2, R2 = 0.23) and more often male (88.0% vs 59.4%; R2 = 0.08). In multivariate analysis, these two factors together explained 37.5% of the differences between groups. No other investigated factor explained more than 2%. If only those patients of obligatory working age were analyzed (n = 1264), Suva cases (50.6%) were more often male than non-Suva-insured (n = 562 [87.8%] vs n = 393 [63.0%], resp.; p<0.001, R2 = 0.08). In multivariate analysis, other factors taken together were only 2.6% of the variance. Conclusions.- Significantly injured patients in Switzerland may be considered comparable from a statistical point of view whether insured by the main accident-insurer or not, provided groups are adequately controlled for age and gender. Other differences appear to be only marginal. Respecting these limitations such data can justifiably be given as Swiss reference statistics and the relevant insurer outcome information used for international comparison.