Medical Review Fundamentals and Regulatory Framework
The reviewer's legal operating environment
A medical reviewer sits at the intersection of clinical judgment and administrative law. Core concepts include the distinction between coverage (is the service a benefit?) and medical necessity (is it clinically justified?), the hierarchy of authority (statute, regulation, sub-regulatory guidance such as manuals and local coverage determinations, then internal policy), and the roles of CMS, Medicare Administrative Contractors, the OIG, and state regulators. Understand the difference between Medicare Advantage and traditional Medicare, the function of the National Coverage Determination and Local Coverage Determination, and why commercial plans follow plan documents and state insurance law rather than CMS manuals.
Documentation standards and reviewer authority
Know the elements of a valid order, the meaning of a signed and dated physician certification for home health and hospice, and the principle that reviewers may not create documentation or infer clinical findings. Reviewers determine whether documentation supports a claim; they do not supply missing facts.
Traps to watch
Questions love to blur the source of authority. A commercial plan citing an LCD as binding is a classic distractor. Another trap is confusing the reviewer's authority with the treating physician's: the reviewer judges sufficiency, not preference. Watch for items that imply retroactive policy application or that treat internal guidelines as law.
Rule of thumb
When unsure which standard applies, ask: who pays, and under what contract? Medicare fee-for-service follows coverage determinations; Medicare Advantage follows the plan's coverage criteria plus general Medicare coverage; commercial follows the benefit plan; Medicaid follows the state plan and waivers. That single question resolves most framework items.