An example of a domain generalization hierarchy for the diagnosis information. In this example we can see that at the lowest level (level 1) this variable is disclosed with the most detail: the actual ICD-10 most responsible diagnosis. This can be generalized into the CMG_CODE (panel a), which is not a simple generalization from MRDx, but also considers other information about the acute admission (level 2). The MRDx value can also be generalized to a three character code DIAG3 (panel b), which is a direct generalization in the ICD-10 hierarchy. The diagnosis can be further generalized to the ICD-10 block (level 3), and then the chapter (level 4).
Emam et al. BMC Medical Informatics and Decision Making 2011 11:53 doi:10.1186/1472-6947-11-53