The Interactive Advertising Bureau has opened its Cross-Channel Measurement Decision Guide for public comment through November 4, and it proposes that a measurement conversation begin with the budget decision at hand rather than with whichever report arrived first.
IAB released the guide on October 20 as a Project Eidos deliverable. Its release describes a decision-first approach to selecting, interpreting and applying evidence from marketing mix modeling, incrementality testing and attribution, “including when their findings appear to tell conflicting stories.” The comment window runs 15 days, from October 20 to November 4, which matters for any team that plans to ask for changes.
What IAB published
The guide has three connected parts, according to IAB’s announcement. The Decision Guide sets out a sequence that runs from business outcome to decision, measurement question, measurement approach, evidence, interpretation and action. The Decision Navigator applies that sequence to common decisions, such as allocating budget across channels or assessing whether an investment is creating incremental value. The Measurement Reference Library collects existing metric definitions and supporting context so readers can interpret the evidence the first two parts rely on.
The guide is written for marketers, agency teams and measurement partners. IAB is asking commenters three things: whether the guide reflects real-world measurement decisions, whether its method-fit and interpretation guidance holds up when results conflict, and whether its scenarios are realistic enough for day-to-day planning.
The case IAB chose to test
David Cohen, CEO of IAB, framed the problem in the release: “Measurement only works if the industry trusts the answers it produces, and right now, MMM, incrementality, and attribution can each tell a different story about the same campaign.” He added that the guide does not ask marketers to pick a winner among the methods.
Matt Shapo, Senior Director, Measurement at IAB, named the scenario he wants commenters to stress: a channel reports a strong attributed ROAS that an incrementality test does not back up. That is a familiar planning-meeting standoff. Two reports disagree, each owner defends their own, and the budget decision waits. A decision-first sequence gives the room a fixed order of questions: what is being decided, what question that decision needs answered, and which method is built to answer it.
Shapo said of the guide: “We built this to be used, not just read.” Cohen called the guide “exactly the kind of foundational work Project Eidos was built to do.” The release also cites a range of 60% to 75% saying advanced measurement falls short on dimensions such as rigor, timeliness, trust and efficiency.
Measurement is also a contract question
The guide follows another IAB measurement document by about a month. On September 22, IAB released the Measurement Services Addendum v1.0 for public comment, a standard contractual framework for companies that provide, purchase or use measurement, verification, attribution and analytics services. That comment period closed on October 22. Cohen said in that release that “the legal frameworks supporting those relationships have often been shaped one agreement at a time.”
Read together, the two documents cover both ends of a measurement relationship. The addendum covers what a buyer and a provider agree to in writing. The decision guide covers what a marketer does with the numbers that come back.
Where it meets recent MarTech coverage
Several recent stories on this site show the problem the guide addresses. In ChatGPT Ads Measurement Has Two Routes, and One Sale Can Count Twice, a browser pixel and a server-side API both report conversions, and matching event IDs are what keep one sale from being counted twice. Google’s Data Strength Uplift metric, covered in Google Adds Data Strength Uplift Metric and Extends Data Manager to DV360 and GA, reports conversion gains from an advertiser’s own data setup. Each is a number produced inside a platform’s own reporting. A team that holds an incrementality result for the same spend has two figures to reconcile, which is the situation the guide’s interpretation guidance addresses.
What it means for the marketing leader
The guide is a draft, and its value to a marketing team depends on whether the sequence survives contact with a real budget meeting. Three uses are available before the window closes.
First, take one decision already on the calendar for the next quarter, such as moving spend between two channels, and write it out in IAB’s order: outcome, decision, measurement question, approach, evidence, interpretation, action. Where the chain breaks, that is the missing piece of evidence.
Second, find a live conflict between two methods in your own reporting. If a platform’s attributed return and a holdout result disagree, bring that case to the guide. Shapo asked for exactly this kind of scenario.
Third, check how your measurement vendor contracts treat the questions the addendum raises. Our earlier opinion piece, Ask Marketing Analytics Vendors for Lead Time Before Explanations, made the case for writing a figure for alert lead time into the vendor contract. The addendum is a template for that conversation, even though its comment period has ended.
In our reading, the guide will be judged on how it handles conflicting results. A sequence that works when the methods agree needs little help. Guidance on what a team does when MMM, incrementality and attribution disagree is the part worth reading closely, and the part where practitioner comments will matter most before November 4.
IAB’s announcement links to the guide and to the comment submission.
Source: IAB
