CO 9 and CO 10 Denial Code

CO 9 Denial Code – The diagnosis code is inconsistent with the patient’s age:

Insurance will deny the claim with CO 9 denial code – The diagnosis code is inconsistent with the patient’s age, when the diagnosis code is not compatible with the patient’s age.

CO 10 Denial Code – The diagnosis code is inconsistent with the patient’s gender:

Insurance will deny the claim with CO 10 denial code – The diagnosis code is inconsistent with the patient’s gender, when the diagnosis code is not compatible with the patient’s gender.

Let us consider below examples to understand the CO 9 denial code:

Scenario 1:

Let us assume Mike (41 year old) has done is BMI.

Body Mass Index (BMI) ICD 10 diagnosis codes Z68 series and they are coded correctly based on the patient’s age.

They have expanded Z68 series diagnosis codes into adult and pediatric BMI categories and this will be coded, based on patient’s age.

Answer: ICD 10 diagnosis code is Z68.41 (Body Mass Index 40.0-44.9 adult).

Suppose if they have coded the claim with Z68.45 diagnosis code (Body Mass Index 70 or greater adult), claim will be denied with CO 9 Denial Code – The diagnosis code is inconsistent with the patient’s age. Because patient’s age is 41 and the diagnosis code Z68.45 is for age 70 or greater adult. Correct diagnosis code Z68.41.

Scenario 2:

Let us assume health examinations done for newborn baby (26 days old).

Encounter for newborn, infant and child health examinations, Z00 series diagnosis code coded correctly based on child’s age.

Answer: ICD 10 diagnosis code – Z00.111 (Health exam for newborn, under 8-28 days old).

Suppose if they have coded the claim with Z00.110 diagnosis code (Health exam for newborn, under 8 days old), claim will be denied with CO 9 Denial Code – The diagnosis code is inconsistent with the patient’s age.

Now let us see examples for CO 10 denial code:

Scenario 1:

Let us assume a female patient is diagnosed with tuberculosis of Cervix and provider performed the services. How the diagnosis codes are reported?

As we know certain diagnosis codes are there for females and some of them for males only

So the above example the correct ICD 10 diagnosis code is A18.16 – Tuberculosis of Cervix which is for females only.

Suppose if the claim billed with an incorrect diagnosis code A18.14 – Tuberculosis of Prostate which is for males only, then the claim will be denied with CO 10 denial code – The diagnosis code is inconsistent with the patient’s gender.

With the above example we come to conclusion that coding team should be very careful while coding the claims in order to avoid the above denials.

When claim denied with CO 9 or CO 10 denial code, need to ask the following questions with rep for solutions:

• Get receive and denial date of the claim.
• If the denial Code is CO 9 verify which diagnosis code is inconsistent with patient’s age and if the denial code is CO 10 verify which diagnosis code is inconsistent with patient’s gender?.
• Check with coding team for correct diagnosis code which is consistent with patient’s age or Patient’s gender. (If the coding team suggests correct diagnosis code, then update and resubmit the claim as corrected claim).