Healthcare Cost and Utilization Project
HCUP-3 Research Note

Clinical Classifications for Health Policy Research: Hospital Inpatient Statistics, 1995


This Research Note provides descriptive statistics for U.S. hospital inpatient stays in 1995 using the Healthcare Cost and Utilization Project Nationwide Inpatient Sample. National estimates are provided for all discharges by principal diagnosis and by principal procedure. Statistics are presented on the number of discharges, mean length of stay, mean charges, charges in quartiles, percent who died in the hospital, percent male, and mean age. Diagnoses and procedures are categorized using the Clinical Classifications for Health Policy Research (CCHPR), a system for collapsing diagnosis and procedure codes into clinically meaningful categories.

Key information from the Research Note is summarized here. Select to access the full text of Clinical Classifications for Health Policy Research: Hospital Inpatient Statistics, 1995. Print versions of the HCUP-3 Research Note (AHCPR Publication No. 98-0049) are available from the AHCPR Publications Clearinghouse (P.O. Box 8547, Silver Spring, MD 20907, Telephone 800-358-9295).

By Anne Elixhauser, Ph.D., MEDTAP International; Claudia A. Steiner, M.D., M.P.H., Agency for Health Care Policy and Research; Charlotte A. Whittington, B.A., Social and Scientific Systems; and Eileen McCarthy, B.A., National Center for Health Statistics.

Today's unprecedented volume and pace of change in the health care system requires a new information paradigm in which evidence-based, standardized databases and the tools for using them are available to State and local users in a timely, meaningful format. Health care managers and other decisionmakers need user-friendly data and tools that will help them assess the effects of health care program and policy choices; accurately measure outcomes, community access to care, utilization, and costs; and guide future health care policymaking that will maintain both high quality of care and good value for the health care dollar.

The Agency for Health Care Policy and Research (AHCPR) has developed an array of health care decisionmaking and research tools that may be used by program managers, researchers, and others at the State and local levels. The Healthcare Cost and Utilization Project (HCUP) Clinical Classifications for Health Policy Research (CCHPR) tool, which is the subject of this Research Note, is the latest one to be released. This version of the CCHPR includes all ICD-9-CM coding changes through September 1998.

The CCHPR software program aggregates ICD-9-CM codes, about 12,000 diagnosis codes and 3,500 procedure codes in total, into a smaller number of clinically meaningful, relatively homogenous clusters. ICD-9-CM codes are the standard codes used in all institutionally based records (e.g., hospitals, outpatient surgery centers) and in insurance claims data. CCHPR can be applied to all ICD-9-CM data from 1980 to date, with simple adjustments needed for data prior to 1993. CCHPR, a "clinical grouper," makes ICD-9-CM data more amenable to clinically focused statistical analyses. In studying hysterectomies, for example, if clinically focused researchers were to work only with ICD-9-CM coded data, they would need to search for six ICD-9-CM codes to reign in all hysterectomies. If these same researchers were to use ICD-9-CM coded data grouped into DRGs, the data would mask clinically relevant data, such as the number of oophorectomies that were performed as part of the hysterectomy. By using CCHPR, researchers can easily identify hysterectomies as well as oophorectomies.

Other types of questions that CCHPR may be used to address include the following:

CCHPR categories can be employed in many types of projects analyzing data on diagnoses and procedures, such as identifying populations for disease- or procedure-specific studies; providing statistical information (such as length of stay) about relatively specific conditions; defining comorbidities; and cross-classifying procedures by diagnoses to provide insight into the variety of procedures performed for particular diagnoses.

CCHPR users include insurers and managed care organizations that want to examine claims experience in a clinically meaningful way, State data organizations or hospitals that want to develop clinically based utilization profiles, and pharmaceutical and device manufacturers that want to assess unmet clinical needs.

More Information

More information on CCHPR and other AHCPR tools and data for policymakers and researchers is available online. We invite you to write to the address below to tell us how you are using CCHPR and to share your comments on how CCHPR might be improved to better meet your research and decisionmaking needs.

Irene Fraser, Ph.D.
Director, Center for Organization and Delivery Studies
Agency for Health Care Policy and Research
2101 East Jefferson Street, Suite 605
Rockville, MD 20852

Current as of January 1999

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Internet Citation:

Clinical Classifications for Health Policy Research: Hospital Inpatient Statistics, 1995. HCUP-3 Research Note, Summary. Agency for Health Care Policy and Research, Rockville, MD.

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