# Substantiation

> Substantiation is the evidentiary backing for a promotional claim — the demonstrable link between what a pharma material says and the data that supports it, verified during MLR review.

> **Substantiation** is the evidentiary backing for a claim: the demonstrable link between a statement in promotional material and data that actually supports it. In US promotional review, claims must be truthful, non-misleading, and supported by substantial evidence consistent with the approved label; verifying that link — claim by claim, passage by passage — is the medical reviewer's core job in [MLR review](/glossary/mlr-review/).

Substantiation failures are the dominant class of review findings, and they're rarely fabrications — they're *overreach*: the source reports 38%, the slide says 42%; the study ran 24 weeks, the copy implies durability; the population was adults, the imagery suggests broader use. Each is a claim whose wording wandered past its evidence.

Operationally, substantiation is managed through the [claims matrix](/glossary/claims-matrix/) (approved claim ↔ approved evidence) and demonstrated through [annotated references](/glossary/annotated-references/) (locator to the exact passage). The strictest working standard is *sourced-only* writing: no claim enters a deliverable unless its substantiating passage is already identified — which converts substantiation from a review-time investigation into a writing-time constraint.

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Source: https://medcom.claims/glossary/substantiation/ · Updated 2026-07-13 · © Mantir, Inc.