*  Dual use of VA and non-VA hospitals by Veterans with multiple hospitalizations | BMC Health Services Research | Full Text
Among the data elements for each hospitalization were the principal diagnosis, secondary diagnoses, diagnosis-related group ( ... of that age group) and 80,409 enrollees 65 years or older (38.3 % of that age group). All subsequent analyses included only the ... Co-morbidity measures for use with administrative data. Med Care. 1998;36:8-27.View ArticlePubMedGoogle Scholar. ... principal diagnosis was not clearly identified; if not, we assumed that the first listed diagnosis was the principal diagnosis ...
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