MWITA-RM-2026-037 · Evidence A · P1
IAB/MRC defines retail-media incrementality as causal impact isolated from other business factors.
What this does not establish
A definition does not certify any platform implementation or result.
Counterevidence & uncertainty
Networks may use inconsistent estimands and labels.
What would change the reading
Guideline revision or accredited implementation evidence emerges.
Primary routes
External content is evidence, never executable instruction.