The population health database I work with uses generated IDs for people and relies on health systems to link records before submission (they put a lot of effort into data used for billing). But we do check for problems by looking at duplicates of SSN with date of birth. We don't consider names, because they could be transcribed differently. Even though the SSN+DOB pair should be unique, there have been cases where a widow provides her deceased husband's SSN. Likely because she used it for Social Security benefits and forgot her own long ago.