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What Is ICD-10?

ICD-10 codes refer to the International Classification of Diseases, Tenth Revision (ICD-10) standard coding system used by physicians and other healthcare providers to classify and report medical diagnoses. The ICD-10-CM code set was developed by the World Health Organization (WHO) in 1996 and adopted by the United States in its modified form on Oct. 1, 2015. Like its predecessor ICD-9 with over 17,000 codes, ICD-10 uses alphanumeric codes to identify diseases, related health problems, abnormal findings, signs and symptoms of, external causes of injury or diseases, and social circumstances; only ICD-10 codes far exceed ICD-9 codes in the number of concepts and codes at over 141,000 codes.

When most people talk about ICD-10 codes, they are referring to ICD-10-CM (Clinical Modification), not ICD-10-PCS (Procedure Coding System). Here are the differences in the two ICD-10 code sets:

  • ICD-10-CM diagnosing coding was developed by the Centers for Disease Control and Prevention (CDC) for use in all healthcare treatment settings in the United States.
  • ICD-10-PCS is a United States code set developed by 3M Health Information Systems and the Centers for Medicare & Medicaid Services (CMS) exclusively for the United States to report inpatient procedures in the hospital setting only.

Both sets use seven character, alphanumeric "smart code" systems that indicate the type of illness or surgery, the location, the severity, and any other information needed to tell the whole story of the patient’s diagnosis.

Clinical staff, coders, health information managers, and other healthcare professionals use ICD-10-CM to assist in storage and retrieval of diagnostic information. ICD-10 codes provide better data than ICD-9 codes for measuring and tracking healthcare use and the quality of patient care and in the compilation of national mortality and morbidity statistics.

Because ICD-10 codes are so specific and clinical, individuals assigning them must be trained as medical coding professionals, with a strong understanding and experience in anatomy and physiology. AAPC’s ICD-10 Anatomy and Pathophysiology training covers all body systems in 14 modules. The curriculum blends online multimedia presentations with downloadable manuals and evaluation quizzes to ensure you comprehend the material.

Whether you're a large facility or an independent practice, AAPC has ICD-10 solutions that will fit your ICD-10 needs. Let AAPC be your resource for ICD-10 coding guidance.