Physiatry Practice Management Resources

ICD-9-CM codes are used to indicate why a CPT procedure or service was performed. This diagnosis code is as important as the procedure code because the diagnosis must support the procedure or else the claim will be denied. Most third-party payors have claims "edits" or automatic denial/review commands within their computer software to review claims for CPT to ICD-9-CM coding accuracy.

In March 1994, HCFA published the ICD-9 coding and reporting requirements in the Federal Register. The ICD-9-CM is a three-volume set of codes. Volumes 1 and 2 contain diagnosis codes and symptoms and are used primarily for physician billing. Volume 3 is used for skilled nursing facility and hospital billing. Physicians must use the ICD-9-CM codes listed in categories 001.0 - V82.9.

Key Steps

To improve the accuracy of your ICD-9 coding, you need to select the correct code, assign a diagnosis code and report the code you select. It is also good practice to establish strong business processes to regulate your ongoing coding.

Select the Correct ICD-9 Code

The following steps were adapted from HCFA's ICD-9 coding and reporting requirements:

1. Physicians must use ICD-9 CM codes that are listed in categories 001.0 - V82.9.

2. Select and report the ICD-9-CM code for the diagnosis, condition, problem or symptom that is documented in the medical record as the primary reason for the encounter. List any additional codes that describe any coexisting conditions. Never add to or subtract from statements made by the provider. If necessary, request additional records to clarify conditions. To select the most appropriate code from the ICD-9-CM Code Book, perform the following steps:

• Look up the main term in the alphabetic index (Volume 2) and scan the sub-term entries as appropriate. Do not code from the alphabetic index without verifying the accuracy of the code (i.e., 4th and/or 5th digit) in the tabular list.
• Locate the ICD code in the numerically arranged tabular list (Volume 1).
• Observe the punctuation, footnotes, cross-references, color-coded prompts and other symbols indicated in the book.
• To determine the appropriateness of the code selection, read all instructional material:
  • "Includes" and "excludes" codes.
  • "See", "see also", and "see category" cross-references.
  • "Use additional code" and "code fist underlying disease" instructions.
  • "Code also" and "omit code" notes.
  • Fourth and fifth digit requirements.
  • CC exclusions.
  • Confirm and report the correct code.

• When filing claims, all ICD-9 codes should be reported in box 21 of the HCFA 1500 claim form.
• Enter up to 4 codes in priority order (e.g., primary condition, secondary condition). When coding multiple diagnoses, first list the primary diagnosis, condition, problem or other reason for the medical service or procedure. This is the diagnosis that receives the most attention during the visit. Then follow with any other diagnoses that you are managing or are contributory.
• Make sure that the procedure/service code (CPT-4) matches the diagnosis code (ICD-9).
  • For example, a patient comes into the office for routine diabetes monitoring and also complains of chest pain. You perform an EKG during the visit, but the claim form only lists the ICD-9 for diabetes. It is likely that the insurer will not pay for the EKG because the claim form did not support that it was medically necessary. The ICD-9 code for chest pain should also be listed to support the EKG procedure.
  • Relate the date of services and procedures performed to the primary diagnosis. To do this, enter the diagnosis code from box 21 into box 24e. Enter only one code per line in box 24e. If two or more diagnoses are required for a procedure code (e.g., pap smears), you may only reference one of the diagnosis codes in item 21. Multiple codes in box 24e will make the claim unprocessable.
  
  

• Make sure that your medical billing staff is trained, understands medical terminology, and knows how to use the ICD-9 and CPT references.
• Develop a list of the most commonly used ICD-9 codes within your practice. Keep it handy for the billing person and be sure to update it annually.
• It is important to select codes as close to the time of care as possible so that the encounter is fresh in the clinician's mind.
• Make sure that a clinician is available to explain diagnoses, answer questions, and review ICD-9 coding with the responsible billing person.
• If you are using a billing service, routinely audit the service and require performance guarantees to be sure they are reporting ICD-9 codes correctly.
• Track and review claims denials. Identify instances when incorrect coding is the reason for the denial and address improvements with staff and physicians.

• For outpatient services, select codes that identify the acute conditions of an emergency situation such as coma, loss of consciousness, hemorrhage, etc.
• When coding inpatient services, list what the conditions are "due to" (e.g., coma, due to subdural hemorrhage).
• When coding multiple injuries, always sequence the most severe first.
• Identify causes of infection as secondary codes (e.g., E coli 041.1).
• Do not use unlisted codes unless there is not enough definitive information to make a code selection.
• Distinguish between acute and chronic conditions when possible.
• Routinely revise superbills and charge tickets to include up-to-date ICD-9 codes.
• Regardless of who does the coding in your practice, the physician who signs the claim form is legally responsible for the codes selected and submitted to payors.
• Keep in mind that haphazard or incorrect coding can lead to allegations of fraud.
• If no definitive diagnosis is determined, code the patient's signs and/or symptoms instead of using "rule out" statements.

Sources
First Coast Service Options Inc. Medifest 2000 Participant Handbook. ICD-9 Coding for Beginners, 1999.
St. Anthony's. ICD-9-CM Code Book. Volumes 1,2,3. Reston, VA: St. Anthony Publishing, 2000.

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