Discharge quarter (DQTR) is derived from either the month of the discharge date or the supplied discharge quarter. If both of those fields are invalid or missing, DQTR is set to zero. For these cases, a temporary discharge quarter = 3 was used for the DRG grouper and ICD-9-CM verification routines because these algorithms require a valid discharge quarter.

For HCUP inpatient data only, a temporary discharge quarter = 3 was used for the DRG grouper and ICD-9-CM verification routines when the discharge quarter was missing or invalid because these algorithms require a valid discharge quarter.