Insurance carriers often deny claims for not being coded to the highest level of specificity. As many billers are not coders they often don’t understand what has gone wrong or how to fix it.
If a service line is denied for this reason they are saying that the diagnosis code needs to be more specific. Some diagnosis codes are only three or four digits but many are five digits. The diagnosis must be coded to the absolute highest level for that code, meaning the most number of digits for the code being used.
For example, the diagnosis for hypertension begins with 401. However if you submit a cliam with the diagnosis 401 it will be denied. The code 401 requires a 4th digit. 401.0 is malignant essential hypertension. 401.1 is benign essential hypertension. 401.9 is unspecified essential hypertension. So to bill a claim with a diagnosis of hypertension it must be either 401.0, 401.1, or 401.9.
Another example of a diagnosis needing to be billed to a higher level of specificity would be diabetes. 250.0 indicates diabetes however you neeed a 5th digit to specify what type of diabetes. 250.00 is diabetes mellitus type two, 250.01 is diabetes mellitus type one (juvenile type), and 250.02 is diabetes mellitus type one uncontrolled and so on.
As you can see in the above example just putting 250.0 does not indicate specifically what the problem is. Without the fifth digit the claim is lacking enough information to be processed and therefore will be denied.
If you are unsure if the diagnosis is coded to the highest level of specificity you can look it up in an ICD9 code book or on the web. There are several websites with current ICD9 codes available. They will indicate if the code is coded to the highest level.
Some practice management systems have scrubbers that will catch under coded diagnosis and give you a warning. Sometimes the biller may recognize a truncated diagnosis (or a diagnosis requiring an additional digit.)
In either case the biller should go back to the coder or provider and ask them to be more specific with the diagnosis code so the claim can be resubmitted.