Measurement
Part of A method for measuring and reporting short form video performance that avoids vanity metrics
When to switch short form video attribution methods
Compare short form video attribution methods for English marketing teams: platform, last click, blended and incrementality testing, plus a before and after table.
What to take away
- The Data (Use and Access) Act 2025 reshapes how consent signals move through ad platforms, so models built on third-party cookies alone need a review.
- Platform-reported views and clicks suit creative testing but overstate conversions against finance records.
- Last click undercounts vertical video, because viewers watch, leave and return later through search or direct.
- Blended measurement and incrementality tests give boards the defensible number, at the cost of speed.
- Pick the method by decision, not by toolcreative choice, budget shift and board reporting each need different evidence.
Why attribution changed recently
Consent and data rules now shape what a pixel can record. The Data (Use and Access) Act 2025 sits alongside UK GDPR and widens the Information Commissioner's Office remit over personal data in marketing. Where tracking depends on signals that no longer arrive, conversion counts quietly fall.
Short form video rarely converts in one sitting. A viewer watches a vertical clip on a phone, closes the app, and buys hours later on a laptop. Attribution methods differ mainly in how they treat that gap.
The four methods compared
Platform attribution
Each platform reports views, clicks and conversions inside its own ads manager. It is fast, free and useful for comparing two edits of the same clip. It is also self-interested, counting any conversion it can associate with an impression.
Four attribution methods compared
Platform
- Speed
- Fast
- Cost
- Free
- Best for
- Creative tests
- Main flaw
- Self-interested
Last click
- Speed
- Fast
- Cost
- Cheap
- Best for
- Simple reports
- Main flaw
- Undervalues upper funnel
Blended
- Speed
- Slow
- Cost
- Moderate
- Best for
- Budget setting
- Main flaw
- Useless per campaign
Incrementality
- Speed
- Slowest
- Cost
- Expensive
- Best for
- Causal answers
- Main flaw
- Needs volume
Last click
Your analytics tool credits the final touch before conversion. That is cheap and easy to explain, but it undervalues upper-funnel vertical video, because most buyers see several clips before they act.
Blended measurement
You compare total marketing spend against total sales over a period, then subtract what other channels explain. It is honest at company level and useless for judging one campaign, so use it for budget setting rather than creative decisions.
Incrementality testing
You hold spend back in matched regions or audience groups and measure the difference. That is the closest thing to a causal answer, though it needs volume, patience and a clean control group.
The short form video measurement and reporting guide 2027 sets out how to combine these into one reporting pack instead of arguing for a single winner.
Before and after: what a method switch looks like
The table shows a fictional brand moving from platform-only reporting to blended plus incrementality testing. Figures are illustrative, not benchmarks.
Method switch: before and after
Before (platform only)
- Reported conversions
- 1,200
- Cost per acquisition
- £18
- Attributed revenue
- £96,000
- Board confidence
- Low
- Decision supported
- Creative testing
After (blended plus test)
- Reported conversions
- 780
- Cost per acquisition
- £31
- Attributed revenue
- £74,000
- Board confidence
- Higher
- Decision supported
- Budget shift
Before (platform only)
- Reported conversions
- 1,200
- Cost per acquisition
- £18
- Attributed revenue
- £96,000
- Board confidence
- Low
- Decision supported
- Creative testing
After (blended plus test)
- Reported conversions
- 780
- Cost per acquisition
- £31
- Attributed revenue
- £74,000
- Board confidence
- Higher
- Decision supported
- Budget shift
Nothing about the campaign changed. The method did. Reported conversions fell by about a third because the platform was claiming credit for sales that would have happened anyway.
The size of that gap matters. Video budgets sit inside the digital economy that the ONS digital economy statistics describe through e-commerce and IT activity.
How to choose between them
Start with the decision in front of you. Choosing between two hooks needs only platform data. Deciding whether to move £20,000 a quarter from paid search into vertical video needs a test with a control group.
Match the method to the size of the spend. A team paying £400 a month cannot run a statistically useful incrementality test, and should not pretend otherwise. Blended reporting plus platform creative data is the realistic option.
Check consent and data flows before you trust any number. The ICO's direct marketing checklist covers consent, suppression and record keeping, which decide whether your tracking is lawful at all.
Agree the reporting rhythm: monthly blended figures with quarterly tests suit most teams, while weekly platform dashboards are for operators, not the board pack. Document the choice and date every figure you publish, as the short form video benchmark research in England advises for market data.
Common questions
Which method is most accurate?
Incrementality testing, run properly with a control group. It measures sales you would not have made without the spend, which is what most budgets are really asking.
Can I use platform data for board reporting?
Only with a caveat. Platform numbers help with creative direction but overstate conversions, so pair them with blended revenue from your finance system.
How long should an incrementality test run?
Long enough to cover a full buying cycle and gather enough conversions for the result to mean something. For most teams that is several weeks, not several days.
Does the Data (Use and Access) Act 2025 change my tracking?
It changes the framework around personal data and enforcement, so review consent flows and record keeping before relying on any attribution output. Take advice from your own legal advisers.
