Classification of Diseases

1. Classification of Diseases Two related classification systems • International Classification of Diseases, Ninth Revision (ICD-9) • used to code & classify mortality data from death certificates • Developed and revised by the World Health Organization (WHO) • International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) • used to code & classify morbidity data from inpatient & outpatient records • Developed by the Health Care Financing Administration (HCFA) • Used in the U.S.

2. ICD-9-CM • Statistical classification system that arranges diseases and injuries into groups according to established criteria • Purpose • classification of mortality & morbidity information for statistical purposes • indexing of medical records by disease and operation • data storage and retrieval

3. ICD-9-CM • “Clinical” used to emphasize the modification’s intent…to classify morbidity data for indexing of medical records and other health care statistics • Numeric codes with descriptions • Annual updates published by Health Care Financing Administration (HCFA) • Medicare Catastrophic Coverage Act passed in 1988 required use of ICD-9 codes on Medicare Part B claim forms…other third party payers followed suit

4. ICD-9-CM • Volume 1 -- Numeric listing of diagnosis codes and descriptions • Volume 2 -- Alphabetical listing of diagnoses with codes and descriptions • A revision -- ICD-10-CM is in the works • Learn more about ICD-9-CM at the National Center for Health Statistics web site

5. Current Procedural Terminology (CPT) Codes • Classification of medical services and procedures • Purpose: to provide a uniform language that accurately describes medical, surgical, and diagnostic services • Provides reliable communication nationwide among providers, patients, and third parties

6. CPT Codes • Developed by the American Medical Association in 1966 • Annual updates made by CPT Panel of the AMA • Each procedure/service has 5 digit code • CPT codes must must be supported by diagnostic codes (ICD-9-CM) • Learn more about CPT codes at the AMA web site

7. Jointly developed by AMA and HCFA Components of documentation history exam complexity of medical decision-making counseling time Level of Service CPT Codes Different CPT codes based on: new vs. established patient Type of history, exam, and decision-making Documentation Guidelines for Evaluation and Management Services

8. Documentation Guidelines • CPT and ICD-9-CM codes must be supported by documentation • To learn more about the Documentation Guidelines go to the HCFA web site • For a history of the documentation guidelines and to view a draft of new guidelines click on “Status Report” at the HCFA web site

9. Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM IV) • Purpose: to provide clear descriptions of diagnostic categories to enable clinicians and investigators to diagnose, communicate about, study and treat people with various mental disorders • Learn more about DSM IV at the American Psychiatric Association web site