ICD-9 Coding

Code to the Highest Degree of Specificity to Avoid Denials

Clinicians who must select ICD-9-CM diagnosis codes should use codes that provide the highest degree of accuracy and completeness, or the greatest specificity. That usually means providing an ICD-9-CM code carried to the 5 ^th digit. The Centers for Medicare and Medicaid Services (CMS) require all Medicare practitioners (as do most private payers) to use ICD-9-CM diagnosis codes with the highest specificity as requested by the Health Insurance Portability and Accountability Act (HIPAA). For example, clinicians using code 784.6 (symbolic dysfunction) to describe language/cognitive impairments of an organic nature may have this code rejected. Because this code category has 5 ^th digit subclassifications, the most appropriate subclassifications should be selected. This might be 784.60 (symbolic dysfunction, unspecified), 784.61 (alexia and dyslexia) or 784.69 (other; acalculia, agnosia, agraphia, apraxia). Code 784.69 is intended to include multiple diagnoses, some of which may differ significantly, according to David Berglund, MD, MPH, at the National Center for Health Statistics/Centers for Disease Control, but it provides the highest level of specificity in that category and therefore should be used instead of 784.6. Keep in mind that 784.60, 784.61, and 784.69 are subclassifications of 784.6, so when you use those codes, you are not excluding 784.6.

Following the specificity rule, therefore, assign 3 digit codes when there are no 4 digit codes within the category. (So far, only one 3-digit code relevant for ASHA members has been found, 931-foreign body in ear.) Assign 4 digit codes if there is no 5 ^th digit subclassification for that category. Assign the 5 ^th digit subclassification code for those categories where it exits.

Providers should also be aware that codes marked NOS (not otherwise specified) or "unspecified" indicate that there is insufficient information in the medical record to assign a more specific code. NEC (not elsewhere classifiable) means that ICD-9-CM does not have a code that describes the condition.