How are the underlying causes of death grouped in VistaPHw?
Due to the detailed nature of the ICD classification system, it is common to group ICD codes into more general categories for analysis and comparison purposes. VistaPHw uses the classification system provided by the National Center for Health Statistics (NCHS) in which causes of deaths for adults are grouped into 113 separate groups and deaths for infants into 130 groups. NCHS groupings are also used in the Washington State Center for Health Statistics publications.
