Using Many-to-Many Relationships in Multidimensional SQL Server Analysis Services

In the health care world, claims are identified by many attributes. A frequently requested attribute is Diagnosis. These codes are used to identify types of claims and categorize claims for reporting and analytics. But once users request slicing by more than just the Primary Diagnosis, the one to many option is no longer valid. What can be done in Dimensional Modeling and Multidimensional Analysis Services to handle this request?