Final answer:
The 'reason rule' is the main rule in ICD coding which states that the primary diagnosis or reason for a patient's visit should be coded first. ICD codes are extensively used in the healthcare system, from guiding medical treatments and tests to assisting in billing and epidemiological statistics. These codes are typically found in medical laboratories and on health insurance claim forms.
Step-by-step explanation:
The correct answer to the question is b. reason rule. According to ICD coding conventions, the reason rule specifies that the main condition or chief complaint for which a patient seeks treatment should be recorded first. This is essential because it prioritizes the primary diagnosis during the encounter, which guides subsequent medical actions, including laboratory tests, treatments, and billing processes. For instance, when a patient is treated for a viral infection, the relevant ICD code for that specific virus is initially used to determine the appropriate laboratory tests and treatments.
ICD codes are integral to the healthcare system in numerous ways. Medical laboratories utilize these codes to identify the necessary tests for confirming a diagnosis. Additionally, health-care management systems employ ICD codes to ensure that all treatments and lab work are suitable for the diagnosis. Medical coders use ICD codes for assigning accurate procedure codes, while medical billers rely on them to process insurance claims. Lastly, ICD codes are used by vital-records keepers to note the cause of death on death certificates, and epidemiologists use them for calculating morbidity and mortality statistics.
Two common locations where one would likely find ICD codes include medical laboratories (where they are used to identify tests) and health insurance claim forms, where they are used to justify medical billing and reimbursement.