Disease staging: CliniCal anD CoDeD Criteria - HCUP

Preface
Since its initial development in the late sixties, Disease Staging has undergone
extensive review. The inclusion of criteria for additional diseases and periodic
adjustments of laboratory data and diagnostic code assignments have ensured the
timeliness, accuracy, and clinical relevance of Disease Staging.
Much of the initial development of Disease Staging was sponsored by the Office of
Planning, Evaluation, and Legislation, the evaluation component of the Health Services
Administration with the (then) Department of Health, Education and Welfare. The
Staging concept was used to develop medically meaningful clusters of patients in terms
of disease severity. Staging was also designed as a quality assurance tool for evaluating
ambulatory care by comparing levels of severity at the time of hospitalization for patients
receiving their health benefits from different government and private insurers.
Later development of Disease Staging was sponsored by the National Center for Health
Services Research (NCHSR), a branch of the Public Health Service. Under contract to
NCHSR, SysteMetrics (which is now part of The MEDSTAT Group) assembled a panel
of physicians to develop Disease Staging criteria for 400 high-incidence diseases.
Computer software was developed to apply Disease Staging criteria to automated
hospital discharge abstract data. This software was validated in re-abstracting studies
that compared manual and computer staging on a large sample of records. Results
showed a high level of agreement between stages assigned manually using the full
medical record and stages assigned by computer software operating on automated
discharge abstract data.
Since the completion of the NCHSR work in 1983, improvements include the clinical
modification of Staging criteria to reflect current clinical practice and the annual updating
of coded Staging criteria to reflect current coding conventions. The result is a more
complete and more precise system for defining disease severity. The Disease Staging
definitions thus reflect the severity of a disease at any given time and the clusters have
clinical significance in terms of prognosis and choice of therapy. Policy makers, health
care administrators, and researchers, both in the United States and other countries,
have applied Disease Staging in risk adjustment evaluations of health care efficiency
and effectiveness.
Three decades of work developing Disease Staging have allowed the writer to
appreciate the dedicated work of many, both in medicine and in other professions. The
contributions of colleagues in the development of the first four editions, as well as the
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