National Hospital Discharge Survey--Revision

Current NHDS The National Hospital Discharge Survey (NHDS) has been conducted continuously by the National Center for Health Statistics, CDC, since 1965. It is the principal source of data on inpatient utilization of short-stay, non-Federal hospitals and is the principal annual source of nationally representative estimates on the characteristics of discharges, the lengths of stay, diagnoses, surgical and non-surgical procedures, and the patterns of use of care in hospitals in various regions of the country. It is the benchmark against which special programmatic data sources are measured. The data items collected are the basic core of the variables contained in the Uniform Hospital Discharge Data Set (UHDDS) in addition to several variables (admission source and type, admitting diagnosis and present on admission indicators) which are identical to those needed for billing of inpatient services for Medicare patients. In the current survey, data are obtained in one of three ways: Abstracted by hospital staff; abstracted by Bureau of the Census Staff under an interagency agreement; and provided in electronic format. Due to budgetary constraints, the number of hospitals and the number of discharges for the 2008 and 2009 NHDS data collections will decrease by approximately 50% from previous years.

Proposed Revision

Although the current NHDS is still fulfilling its intended functions, it is based on concepts from the health care delivery system, as well as the hospital and patient universes, of previous decades. It has become clear that a redesign of the NHDS that provides greater depth of information is necessary.

• In 2008, a sample of 30 hospitals will be selected for a pretest. These hospitals will not be a probability sample, but instead will be intentionally selected to include hospitals of differing size, location and other characteristics related to their service and patient clientele.
• In 2010, a redesigned NHDS will be implemented and will consist of a completely new sample of approximately 240 hospitals. The redesigned NHDS will use a modified two stage design. The first stage sampling will be hospitals. The second stage of sampling will be discharges. A stratified, random sample of 120 discharges is targeted within each hospital. In the redesigned survey all data will be abstracted by trained health care staff under contract. All data will be obtained from hospital records and charts and computer systems.

The current data items will be collected with significant additional details. Patient level data items to be collected include:

• personal identifiers such as social security number (last 4 digits), name and medical record number;
• clinical laboratory results such as hematocrit and white blood cell count; and
• financial billing and record data.

The survey includes detailed questions for three modules:

• Acute myocardial infarction;
• infectious disease; and
• end of life issues.

Facility level data items include demographic information, clinical capabilities, and financial information.