Types of Ambulatory Surgery and Other Outpatient Services Collected by the Partner

The District of Columbia Hospital Association (DCHA) collects data on ambulatory surgery and other outpatient services. The types of services collected are based on the following Uniform Billing Form (UB-04) bill types: ambulatory surgery center (bill type 83x), hospital outpatient (bill type 13x), and critical access hospital (bill type 85x). The collected outpatient data include ambulatory surgery, emergency department visits, and observation stays.

Outpatient Data File Provided to HCUP by the Partner

Starting in data year 2021, DCHA provides HCUP with a combined outpatient file including records for ambulatory surgery, emergency department (ED), Fast Track ED, observation stays, outpatient clinic, imaging, pathology, and lab. Prior to 2021, the file provided to HCUP was limited to ambulatory surgery and ED records including Fast Track ED.

Excluded from the source data provided to HCUP are records for freestanding ED visits, ambulatory surgery from freestanding clinics, and prior to data year 2021 observation stays after an ED visit, and observation stays without ED services.

Through September 30, 2015, ambulatory surgery records were defined based on at least one of the following criteria:

1. ICD-9-CM ranges included codes 00.50-86.99 (excluded were procedure codes in the range 88.4-88.59),
2. CPT procedures codes indicating surgery (yearly updates can be downloaded from Centers for Medicare and Medicaid Services (CMS) and generally include 10121-69930, G0105, G0121, and G0260),
3. Presence of at least one revenue center code in the following range 036x (operating room services), 037x (anesthesia), or 049x (ambulatory surgical care), or
4. Presence of a UB04 bill type of 83 indicating outpatient services. A new definition of ambulatory surgery beginning October 1, 2015 with the transition to ICD-10-CM/PCS is not available.

Selection of Records for Inclusion in the SASD

All records identified by DCHA as ambulatory surgery are included in the SASD (STATE_AS=1 based on type of treatment code "3"). Any other nonemergent outpatient records (STATE_ED not equal to 1) also are included in the SASD.

Additionally, any records in the SASD that also have evidence of emergency department services based on the HCUP criteria (HCUP data element HCUP_ED > 0), are also included in the HCUP State Emergency Department Databases (SEDD). These records will have the same value for the HCUP data element KEY.

Types of Facilities Included in the Files Provided to HCUP by the Partner

DCHA collects data on ambulatory surgery and other outpatient services performed in hospital-owned facilities. DCHA does not collect data from ambulatory surgery facilities that are not owned by a hospital.

Identification of Hospital-Owned Ambulatory Surgery and Other Types of Outpatient Facilities in the SASD

The designation of a facility as hospital-owned is specific to its financial relationship with a hospital that provides inpatient care and not related to its physical location. Hospital-owned ambulatory surgery and other outpatient care facilities may be contained within the hospital, physically attached to the hospital, or located in a different geographic area. The designation as hospital-owned means that HCUP can identify that the hospital is billing for this service.

Starting in data year 2018, the HCUP data element HOSPITAL_OWNED can be used to identify hospital-owned facilities with ambulatory surgery and possibly other outpatient care data in the SASD. A facility is considered hospital-owned (HOSPITAL_OWNED = 1) if any one of the following is true:

• The facility is listed in the American Hospital Association (AHA) Annual Survey Database^TM.
• The facility is not listed in the AHA database, but the facility provides inpatient discharge data to HCUP.
• Documentation provided by the data source clearly indicates that the facility is hospital-owned.

If the facility in the SASD does not meet any of the above criteria, it is marked as not being owned by a hospital (HOSPITAL_OWNED = 0). Not all hospitals report to the AHA, so there is a possibility that some facilities marked with HOSPITAL_OWNED=0 are hospital-owned.

From data year 1998-2018, the HCUP data element was called FREESTANDING. A facility is considered hospital-owned (FREESTANDING = 0) if any one of the following is true:

• The facility is listed in the American Hospital Association (AHA) Annual Survey Database^TM.
• The facility is not listed in the AHA database, but the facility provides inpatient discharge data to HCUP.
• Documentation provided by the data source clearly indicates that the facility is hospital-owned.

If the facility in the SASD does not meet any of the above criteria, it is marked as not being owned by a hospital (FREESTANDING = 1). Not all hospitals report to the AHA, so there is a possibility that some facilities marked with FREESTANDING=1 are hospital-owned.

Exclusion of Records During HCUP Data Processing

Beginning with 2016 data, records with a discharge disposition of "still a patient" are retained in the HCUP SASD. Prior to 2016 data, these records were excluded.

Beginning in 2010, records with a designation of "admitted as an inpatient" are retained in the SASD, even though this rarely occurs. Prior to 2010, records with a designation of "admitted as an inpatient" were excluded from the files.