ICD-9-CM (International Classification of Diseases, 9th edition, Clinical Modifications) is a set of codes used by physicians, hospitals, and allied health workers to indicate diagnosis for all patient encounters. The ICD-9-CM is the HIPAA transaction code set for diagnosis coding.
The current edition in the United States for morbidity classification, ICD-9-CM, has been in use since 1979. The original intent for the diagnosis codes was for epidemiological and not billing functions, although in the US, the codes are used by payers for billing and reimbursement purposes.
ICD-9 diagnosis codes consist of 3-5 numeric characters representing illnesses and conditions, and alpha-numeric E codes, describing external causes of injuries, poisonings, and adverse effects; and V codes describe factors influencing health status and contact with health services.
On January 16, 2009, the Department of Health and Human Services released the HIPAA Administrative Simplification: Modifications to Medical Data Code Set Standards to Adopt ICD-10-CM and ICD-10-PCS Final Rule (CMS-0013-F).
ICD-9-CM is running out of codes. Hundreds of new diagnosis codes are submitted by medical societies, quality monitoring organizations and others annually. ICD-10-CM will allow not only for more codes but also for greater specificity and thus better epidemiological tracking. This will allow providers to better identify certain patients with specific conditions that will benefit from tailored disease management programs, e.g. diabetes, hypertension, asthma.
The ICD-10-CM codes are very different from those currently used in ICD-9-CM. All codes in ICD-10-CM are alpha-numeric. There may be up to seven alpha-numeric characters, requiring billing software program changes to accommodate the additional digits, as well as extensive coder training. There will be little change in what the physician documents in the medical record; it is how the information is “translated” into ICD coding that will change. ICD-10-CM codes will be able to provide more in depth information about the patient’s condition that can be more easily captured in an electronic medical record. Physician (HCFA 1500) and hospital (UB-04) billing forms have been updated to accommodate the changes.