According to the AMA Guides, apportionment is based on which factor?

• A. Causation
• B. Medical report of treating physician
• C. Pre-existing disability
• D. Informal rating

Answer: (A)

Apportionment, as described in the AMA Guides, is primarily concerned with identifying the extent to which different factors contribute to an individual’s disability or impairment. Causation serves as the foundational principle upon which apportionment is determined. This means that the focus is on the specific causes of the disability — whether they are related to a work injury, pre-existing conditions, or other factors.

In practical terms, when evaluating a case, the medical professionals will consider how much of the impairment or disability can be attributed to the work-related injury as opposed to other causes, such as pre-existing conditions. This assessment is crucial in ensuring that the benefits or compensations provided are fair and aligned with the actual cause of the impairment. Causation gives a clear framework to effectively attribute responsibility and determine the limits of compensation based on contributions from various factors.

Understanding the role of causation in apportionment is essential for both medical evaluations and legal implications regarding disability assessments. By focusing on causation, the AMA Guides ensure that evaluations reflect a more precise and equitable understanding of how different elements impact an individual's overall condition.