[Variations in referral to specialized medical centers of the Swiss disability insurance: role of the referring party].

The Commissions of the Swiss Disability Insurance (CDI), in order to evaluate the degree of disability which determines the right to benefits, can call upon Medical Observation Centers (MOCD) for a pluridisciplinary examination. The utilization rate of the MOCD, by the 28 CDI, varies by a factor of 1 to 50. The goal of this study is to identify the causes of this variation related to the differences in CDI practice. The CDI answered a mail survey. For analysis, they are allocated into 3 groups of equal size: Low, medium and high users of MOCD. There is no association between the use of the official and non-official criteria for referral to MOCD and utilization rate of the MOCD. The CDI have a false perception of their MOCD use; 40% of them underestimate it. Considering together the utilization rate of the substitutes and of the MOCD, variation still persists from 1 to 9 among the CDI. There is no difference in the reasons for non-referral to the MOCD according to the level of utilization. This study failed to identify the causes of the utilization differences of the MOCD by the CDI. Other factors should be examined.