Source Files

Beginning in July, 2007, the Maryland Health Services Cost Review Commission (HSCRC) provides their emergency department (ED) data in a unified outpatient file that also includes ambulatory surgery (AS) data. Prior to July 2007, Maryland retained their ED data in an "Ambulatory Care" data set that in addition AS data, also included clinic and labor & delivery records that did not result in an admission to the hospital.

HSCRC includes an encounter type indicator on their source files that is based on a hierarchical assignment as follows:

• Clinic services (value 01)
• Emergency services (value 02)
• Labor and delivery (value 03)
• Outpatient surgery (value 04)
• All other outpatient (value 05)
• Greenbaum Cancer Center (value 80) (valid from 2007-2011)
• University of Maryland Medical Center Shock Trauma (81) (valid from 2007-2011)

Because of the hierarchical assignment of encounter type, the ED data file would include records for patients treated in the ED, and then treated and released from observation care.

Selection of Records for Inclusion in the SEDD

HSCRC provides HCUP with one outpatient file in which ED records are included with records for other nonemergent outpatient services. All records identified by HSCRC as ED are included in the SEDD (HCUP data element STATE_ED=1 based on encounter type).

Additionally, any other records with evidence of ED services that are flagged by the variable HCUP_ED (i.e., HCUP_ED>0) during HCUP processing are included in the SEDD. If a record in the SASD also has evidence of ED services based on the HCUP criteria (HCUP data element HCUP_ED not equal to 0), then the SASD record is also included in the SEDD. These records will have the same value for the HCUP data element KEY.

SEDD records with evidence of other types of outpatient service, such as outpatient surgery can be identified by the data element OPService.

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

HSCRC provides HCUP with ED data from all licensed hospital-owned EDs in the State. This includes stand-alone (satellite) EDs operating under an acute hospital's main campus license.

A comparison of the number of hospitals included in the SEDD and the number of hospitals reported in the AHA Annual Survey is available starting in data year 2010.

Hospital-owned EDs do not always report data for a full calendar year. Some open or close during the year; others have technical problems that prevent them from reporting data for all months in a year.

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 SEDD. Prior to 2016 data, these records were excluded. Beginning in 2010, records with a designation of "admitted as an inpatient" are retained in the SEDD, even though this rarely occurs. Prior to 2010, records with a designation of "admitted as an inpatient" were excluded from the files.

Additional SEDD Notes

As of July 17, 2019, skinny files containing the patient's ZIP Code (HCUP data element ZIP) are available for the Central Distributor SEDD for data years 2008 through 2017. Users can link the year-specific skinny ZIP Code files to the same year Core file by using data elements YEAR and KEY. Starting in data year 2018, the data element ZIP is stored on the Core file.

HSCRC has warned that the record type indicator in their source data may not always be correct because some hospitals switched the meanings of the data element in some quarters. Analysts are advised to check the revenue codes for emergency department services (REVCDn in the range 450-459) before using the data when this distinction is important.

Charge File for the Maryland SEDD (prior to 2006). Maryland provided summarized charge detail in which charge information is summed within the revenue center. This type of Charges file includes one record per discharge abstract. Each record contains three corresponding arrays with the following information: revenue center (REVCDn), total charge for the revenue center (CHGn), and total units of service for the revenue center (UNITn). For example, if a patient had 5 laboratory tests, REVCD1 would include the revenue code for laboratory, CHG1 would include the total charge for the 5 tests, and UNIT1 would be 5. Beginning in 2006, Maryland provides REVCHGn (and no longer provides CHGn), which includes information about detailed charges associated with the identified revenue centers (REVCDn) and the units of service (UNITn).

2001 SEDD. The data supplied to HCUP came in two files, each with a different format. Data for January to June were in one format, and data for July to December were in an expanded format. The July to December file contained data elements that were not provided for the first half of the year.

1999 SEDD. Sixteen hospitals did not provide all of their emergency department records to the State during varying periods in the latter half of the year. There is no clear pattern to the shortfall, but it is roughly an 18 percent decrease for August through December.