This section provides State-specific information on the original data files provided by the HCUP Partner organizations for the development of the HCUP outpatient databases. Information about the source of the original data files, the types of hospitals included in those files, the records excluded during HCUP processing, and other pertinent information to understand the composition of these files.

Overview of the SEDD

The State Emergency Department Databases (SEDD) include discharge information on emergency department (ED) encounters that do not result in an admission to the same facility (i.e., treated and released, transferred, or died). The SEDD contain ED encounters from most, if not all, hospital-owned EDs in participating States that are translated into a uniform format to facilitate multi-State comparisons and analyses. Information on ED visits that result in an admission to the same facility are included in the State Inpatient Databases (SID). To enumerate all ED visits, SEDD encounters should be combined with SID discharges that originate in the ED.

Selection of Records for Inclusion in the SEDD

Some participating HCUP Partners provide ED data to HCUP in a separate file. Others, however, provide a single outpatient file that includes both ED data and other nonemergency outpatient services. HCUP uses State-defined indicators of ambulatory surgery (AS) and ED records for inclusion in the State Ambulatory Surgery and Services Database (SASD) and SEDD. Records identified by the State as AS are included in the SASD. Records identified by the State as ED are included in the SEDD. Additionally, some States provide indicators of observation services (OS). If available, records with OS in combination with ED services would be included in the SEDD; OS records without ED services would be included in the SASD. Three HCUP data elements (STATE_AS for AS records, STATE_ED for ED records, and STATE_OS for observation services (OS) records) include information on the State-defined record type. They are set to a value of 1 if the State identifies the record as AS, ED, or OS respectively.

HCUP derives data elements during HCUP data processing to indicate evidence on the HCUP record of ED services or OS, per HCUP criteria. These two data elements (HCUP_ED for ED services and HCUP_OS for OS) are on the SASD and SEDD files as well as the SID. The availability of information identifying OS varies substantially across States and data years as it is dependent on the SEDD (as well as the SASD and SID) including the necessary underlying data, such as revenue center codes.

All ED records provided by the specific State are placed in the SEDD (HCUP data element STATE_ED=1 based on State-specific criteria). 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. Descriptions of State-specific criteria can be found in the File Composition documentation available below.

Beginning with the recreated, version 2, 2003 data and data year 2004, some ED records will be included in BOTH the SASD and SEDD. If the HCUP Partner has indicated that the record is an AS record, but there is evidence of ED services on the HCUP records (i.e., ED charges or revenue codes), then the record is placed in both the SASD and SEDD. In the SEDD, these records will have STATE_AS = 1, HCUP_ED > 0. In both the SASD and SEDD, these records with have the same value for the HCUP variable KEY.

In the first version of data year 2003, the allocation of records into the SASD and SEDD was handled differently. HCUP applied uniform criteria based on information available on the HCUP file for the selection of AS records for the SASD and ED records for the SEDD.

For the SASD, the criteria for identifying ambulatory surgery records included the following:

• Presence of at least one ICD-9-CM or CPT-4 procedure in the following ranges:
• ICD-9-CM procedure codes 00.50-86.99 or 88.40-88.59 CPT-4 procedure codes 10040-69999, 70496, 70498, 70544-70549, 71275, 71555, 72159, 72191, 72198, 73206, 73225, 73580, 73706, 73725, 74175, 74185, 75600-75790, 75893-75898, 75952-75954, 75992-75996, 78445, 92287, 92975, 92992-92993, 93501-93581.
• Length of stay of 0 or 1 days, if this information is available.

For the SEDD, the criteria for identifying ED records varied across States because of the differing availability of necessary data elements. We used one or more of the following three criteria:

• A revenue center code in the range 450-459, indicating ED charges; or
• A CPT procedure code in the range 99281-99285, indicating an ED visit; or
• A positive emergency room charge, if revenue center codes are not available

If a record fits both the AS and ED criteria, the record was included in the SASD with an indication of ED services (HCUP variable EDflag > 0) with one exception. If a data source provides only ED data to HCUP, then the combination AS/ED records were placed in the SEDD file with an indication of AS services (HCUP variable ASflag > 0).

For all States, records that fit neither the AS nor ED screen were excluded from the SASD and SEDD. Records excluded from the SASD and SEDD were placed in the State Unused Files (STUF). It became apparent in evaluating the records excluded from the SASD and SEDD that in some cases the HCUP Partners had more information available to them and, therefore, were better able to identify AS and ED records.

If the data elements EDflag or ASflag are on the 2003 data file, then the HCUP file had records excluded and placed in the STUF file. If the data elements HCUP_AS, HCUP_ED, or HCUP_OS are on the 2003 file, then records were not excluded and placed in the STUF file.

Prior to data year 2003, HCUP Partners were asked to provide HCUP with separate ambulatory surgery (AS) and emergency department (ED) source files, if possible, and a combined outpatient file with records flagged by type, as an alternative. Records identified as AS were included in the SASD. Records identified as ED were included in the SEDD. Investigation of these data files revealed that different data sources often defined AS and ED records slightly differently. In addition, a number of the AS and ED source files included other types of outpatient records such as chemotherapy, mammograms, and observation stays.

For a description of the file composition for one or multiple states, check the corresponding boxes below and then click the "View File Composition" button.