In making the switch to ICD-10, many practices may rely on various online “mapping” tools, including the Centers for Medicare & Medicaid Services’ (CMS’) General Equivalence Mappings.
You can type current ICD-9 code into the tool, and it will tell you the corresponding ICD-10 code.
However, conversion is not that simple. Here's an example.
The ICD-9 code for acute serous otitis media is 381.01. If you type this code into many mapping tools, they will tell you the corresponding ICD-10 code is H65.00: acute serous otitis media, unspecified ear.
ICD-10, however, is famously specific. You’ll need to code if it is the right ear, left ear, or bilateral, and if it’s a recurrent condition (right, left, or bilateral).
In fact, only 5 percent of ICD-9 codes have an exact 1:1 mapping relationship with ICD-10. The rest have a 1:2, 1:3, or even 1:4+ relationship. Conversely, there may be multiple ICD-9 codes for a single ICD-10 code. In addition, ICD-10 has new codes with no ICD-9 equivalent.
For these reasons, coding experts say it’s more efficient and accurate to code from the medical record documentation than to use a code convertor. These mapping tools, many of which are free like the CMS GEMs tool, can be a good starting point, but only the physician’s documentation can provide the specificity needed. In addition, relying on documentation means you will always be able to justify code selection and avoid rejected claims.
Be sure to book mark the TMA ICD-10 webpage, for news, education, and links to resources.
Reviewed Dec. 15, 2014
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