Table 7

Example showing the eight combinations when we have two hierarchical quasi-identifiers where we disclose all of their levels

Combination ID

PROV_XXX

AGE_GROUP

GENDER_CODE

MRDx

CMG_CODE

DIAG_BLOCK

DIAG_CHAPTER

CCI_CODE

SHORT_CCI


2a

X

X

X

X

X


2b

X

X

X

X

X


2c

X

X

X

X

X


2d

X

X

X

X

X


2e

X

X

X

X

X


2f

X

X

X

X

X


2g

X

X

X

X

X


2h

X

X

X

X

X


Emam et al. BMC Medical Informatics and Decision Making 2011 11:53   doi:10.1186/1472-6947-11-53

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