Final answer:
The WHO, CMS, AHA, and NCHS are the key organizations that help maintain and update the ICD-9-CM, ensuring its accuracy for disease classification, healthcare management, and epidemiological tracking.
Step-by-step explanation:
The organizations involved in maintaining the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) include the World Health Organization (WHO), which is responsible for the creation and international dissemination of the various editions of the ICD, including oversight and updates. The Centers for Medicare and Medicaid Services (CMS) are involved particularly in the United States for adapting the ICD to ensure it meets the needs of the healthcare reimbursement system. The American Hospital Association (AHA) assists with fielding concerns and queries related to ICD codes from healthcare institutions. Finally, the National Center for Health Statistics (NCHS) plays a role in statistical analysis and epidemiological tracking using ICD codes, which are critical for understanding morbidity and mortality trends. These organizations collaborate to ensure that the ICD remains an up-to-date and effective tool for healthcare classification, billing, and epidemiological studies.