5 Tips for the Novice Medical Coder

Medical coding is an important part of the medical billing process. Although diagnosis coding is just one piece of a coders job, it is one of the most critical factors of coding because it represents the patient's illness, disease, injury, condition, or symptoms that are affecting the patient's health.

Someone new to medical coding or considering a career in medical coding can review the following brief overview of diagnosis (ICD) coding.


Determining the Correct Diagnosis Code

Charges on a medical bill.
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To determine the correct diagnosis codes (ICD), medical coders should use both Volumes 1 and 2 in tandem. Volume 1 is the tabular list of diseases which covers specific diseases and conditions. Volume 2 is the alphabetic list of diseases which provides information necessary to identify particular conditions.

  • Always begin with Volume 2 which describes the condition
  • Use Volume 1 for additional guidance such as the use of additional digits, additional codes, and/or alternative codes
  • Use additional codes when the diagnosis code is insufficient on its own
  • List the underlying disease first and then secondary diagnosis
  • Pay attention to symbols and instructional notes
  • Some codes are only appropriate for patients of a certain age or gender

The Reasons for Using Diagnosis Codes

Insurance reimbursement is the number one reason diagnosis codes are used. Diagnosis codes are essential in getting medical claims accurately paid. Payments for hospital inpatient visits are mainly based on diseases and conditions, which help make up DRG (Diagnosis Related Groups).

In addition, diagnosis codes indicate medical necessity or reason why a patient received the type of care they receive whether it is an x-ray, lab, office visit, or surgery. Insurance payers especially Medicare will deny claims that don't indicate the medical necessity of the patient's visit.

There are other uses for diagnosis codes:

  • To document or report the quality of patient care.
  • To provide accurate communication by using a national classification system that is understood across payers and providers.
  • To report data that is used for a variety of research studies such as diseases, drugs, procedures or trends in health care.
  • To make important administrative decisions such as marketing, staffing, budgeting, and purchasing

The 5 Step Process for Medical Coding

  1. Review the medical documentation reported by the physician, nurse, technician, and/or other clinical staff.
  2. Identify the medical conditions that need to be coded.
  3. Identify the main terms for each condition.
  4. Search for the main term in Volume 2, the alphabetic index
  5. Use the code that was located using Volume 2 and verify it using Volume 1, the tabular list, and apply the appropriate guidelines.

The Classificiation of Diseases and Injuries

There are 17 different classifications of diseases and injuries for main terms and sub-terms of diagnosis that range in number from 001 to 999.

  1. Infectious and Parasitic Diseases
  2. Neoplasms 
  3. Endocrine, Nutritional and Metabolic Diseases, and Immunity Disorders
  4. Diseases of the Blood and Blood-Forming Organs 
  5. Mental Disorders
  6. Diseases of the Nervous System and Sense Organs
  7. Diseases of the Circulatory System
  8. Diseases of the Respiratory System
  9. Diseases of the Digestive System
  10. Diseases of the Genitourinary System
  11. Complications of Pregnancy, Childbirth, and the Puerperium
  12. Diseases of the Skin and Subcutaneous Tissue
  13. Diseases of the Musculoskeletal System and Connective Tissue
  14. Congenital Anomalies 
  15. Certain Conditions Originating in the Perinatal Period
  16. Symptoms, Signs, and Ill-defined Conditions
  17. Injury and Poisoning

In addition to these, there are 2 types of supplemental codes.

  1. V Codes: Supplementary Classification of Factors Influencing Health Status and Contact with Health Services
  2. E Codes: Supplementary Classification of External Causes of Injury and Poisoning

Where to Go for Help

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