The reported age was not used when AGE could not be calculated because Arizona supplied age at discharge.

Beginning with 2005, source AGE is no longer supplied.

Only the calculated age could be used to assign AGE because Arkansas did not supply age in years.

In all years, California assigned the date of birth to admission date when the admission date was not reported and the discharge had a principal diagnosis indicating a newborn (defined as DX1 equal to V3x.0x). This caused the calculated age to be 0 days.

Prior to 1995, California reported ages at discharge. Only the calculated age was used to assign AGE.

Beginning in 1995, California reported ages at admission. When AGE could not be calculated from dates, the reported age was assigned.

Central Distributor only - because of confidentiality restrictions, age in years (AGE) is suppressed or offset by a few years on some records.

Beginning in data year 2014, the reported age was used to assign AGE. Age could not be calculated because the date of birth (DOB) provided by Colorado does not include the day of birth. Only birth month and year are provided. The day of birth was set to 15 for all records.

Beginning with 1998, the Colorado supplied age at admission was used to assign AGE when the age could not be calculated.

From 1994-1997, Colorado supplied age at admission. For consistency with earlier years of the SASD, however, only the calculated age was used to assign the HCUP variable AGE.

From 1988-1993, Colorado did not supply age at admission. Only the calculated age could be used to assign the HCUP variable age.

Beginning in 2004, Florida provides DOB and ADATE for all discharges.

In 1997, patient age could not be calculated from dates since Florida did not report admission or birth dates. During HCUP processing, the reported age was used to assign AGE. From 1998 to 2001, Florida supplied admission date and date of birth for patients less than 11 years old. For patients over 10 years old, the reported age in years was used to assign AGE. Beginning in 2002, Florida reported age for all discharges, but did not provide admission date and date of birth.

AGE may differ by one year from the actual age. When only the year of birth is available, Iowa assigns the day and month of birth to '01', which may cause the age calculated from birth date to be one year less than the actual age.

Beginning in 2013, the supplied age in years is used when the data element cannot be calculated.

Prior to October 1998, ages greater than 100 years should be interpreted with caution. Age is calculated using the birth and admission date, but only a two-digit year for date of birth (DOB) was provided by the data source. An additional indicator variable provided by the data source, the "Century Birth date," indicates whether the age of the patient was greater or less than 100 years. HCUP experience has shown that this indicator was often not set when it should have been. Thus, if the century indicator specified 1800 or the birth date occurred after the admit date, the century for the date of birth was set to 1800. If the birth date is erroneously after the admit date, this rule causes the age in years (AGE) to be incorrectly greater than 100. If the age does not agree with neonatal or maternal diagnoses and/or procedures, the age is set to inconsistent (.C).

Beginning in October 1998, Massachusetts provides a four-digit birth year. The birth century indicator and the admission date are not used to modify the date of birth.

Prior to 2001, age could not be calculated because Michigan did not report admission and birth dates. Beginning with the 2001 data, Michigan provided complete dates and AGE could be calculated.

For discharges less than 90 years old, if the age could not be calculated from dates, then the reported age was used to assign AGE. For discharges that are 90 or older, only the calculated age could be used to assign AGE because Nevada sets age in years to 90 for all discharges age 90 and above.

Beginning in 2009 AGE was provided. In 2008, Age was calculated during the HCUP processing.

Prior to 1994, New Jersey reports age as a two-digit code with a maximum of 99 and provides a birth century indicator. Beginning in 1994, New Jersey provides a four-digit birth year. If age could not be calculated (ADATE or DOB missing or invalid) then age was assigned as follows:

Beginning with the 2008 data, the HCUP data element AGE is missing (.) for AIDS/HIV patients. New York identifies AIDS/HIV records by ICD-9-CM diagnosis code, DRG, or MS-DRG:

• An admitting, principal or any secondary diagnosis of "042", "043", "044", "7958", "27910", "27919", "2793", "1363", "79571", "07951", "07952", "07953", "V017" or "V08".
• A DRG of 488 through 490 (prior to October 2007) or MS-DRG of 700 through 716 (beginning in October 2007).

Please note that the admitting diagnosis is not retained in the HCUP databases prior to 2012.

In the 1988-1997 HCUP New York databases, AGE could not be calculated because New York did not report full admission and birth dates. During HCUP processing, only the reported age in years could be used to assign AGE.

Oregon reports age at discharge. During HCUP processing, reported age was not used when patient age (AGE) could not be calculated from dates. Beginning in 2007, reported age was used if the calculated age was missing.

Prior to 2004, the reported age was not used when AGE could not be calculated because Utah supplied age at discharge. Beginning in 2004, Utah supplied the age at admission which was used during HCUP processing.

Beginning with the 2015 data, the HCUP data element AGE is set to missing (.) in the Central Distributor SID for records involving substance abuse or HIV infection. This was done at the request of the Utah Partner organization.

Availability of Reported Age

During HCUP processing of 1988-1992 discharges, the reported age was not used when AGE could not be calculated because Washington reported age at discharge. The appropriate edit check for consistency of reported and calculated ages could not be performed.

Beginning with 1993 discharges, Washington reported age at time of admission, consistent with the HCUP definition of AGE. Therefore, if the patient's age could not be calculated from dates, the reported age was assigned to AGE.

Ages Greater Than 99 Years

For 1988-1992 discharges, due to the coding of date of birth, no patient ages are greater than 99 years. Only a two-digit year for date of birth (DOB) was provided by the data source.

• If DOB is greater than admission date (ADATE), the birth century was assigned as 18 (e.g., if ADATE = 01/02/88 and DOB = 01/03/88, then the birth year was set to 1888 and the calculated age was 99).
• If DOB is less than or equal to ADATE, the birth century was assigned as 19 (e.g., if ADATE = 01/02/88 and DOB = 01/01/88, then the birth year was set to 1988 and the calculated age in years was 0).

For 1993-1996 discharges, the birth century was assigned as 1800 if the reported age was at least 100 or the reported date of birth was after the admission date. Birth century was assigned as 1900 for all other record. The age range is not truncated at 99.

In 1997, the reported age was no longer used to indicate ages over 100. This is consistent with the coding of AGE in other states. The coding of AGE in 1997 is the same as specified for 1988-1992.

Beginning in 1998, Washington provided a four-digit birth year with the century. If the reported date of birth was greater than the admission date, then the original date of birth remains unchanged and the age at admission (AGE and AGEDAY) was set to inconsistent (.C).

Beginning in 2005, Wisconsin no longer codes ages greater than 96 to 96. Prior to 2005, an error during HCUP processing of 1989-1992 discharges caused age in years (AGE) and date of birth (DOB) to be set to missing (.) for all patients born in the year 1900. Beginning with 1993 discharges, AGE and DOB were processed correctly.

From 1989-1994, only the calculated age could be used to assign AGE because Wisconsin did not supply age in years. The appropriate edit check for consistency of reported and calculated ages could not be performed.

For 1995 discharges, the source supplied an age in years which was used if the age could not be calculated from date of birth and admission date.

Beginning in 1996, only the calculated age could be used to assign AGE because Wisconsin had truncated ages over 96 years to age 96.