Method Summary

Where do the numbers come from?

The UKOM-endorsed comScore approach to online audience measurement uses a combination of metered panel and website, app and video tag data, commonly known as a ‘hybrid’ approach.

Panels and Tagging – The Hybrid Measurement Approach

Panelists are recruited online, incentivised by either free software or cash payments.  People join the panels by providing demographic information (their own and their household’s), before downloading a piece of software (the meter) which tracks visits on their device(s) to websites and apps.  In the case of smartphones and tablets, the meter varies slightly by operating system but essentially the same principles of method are applied to measure browser and app usage across all devices.

With tagging the onus lies with the media owner to implement the appropriate tags for all their digital properties.  Different tags are required for websites, videos and apps.



This hybrid approach ensures that the limitations of any single approach are minimised.  For example, all media measurement panels struggle to capture out of home usage and, in the case of the internet, use of smaller or niche sites and channels ( the ‘long tail’) - but they do provide demographics.  Tagging, on the other hand, ensures that all-location use is represented but it cannot yet deliver audience demographic data.

Crucially, this combination of metered panels and tagging also allows the deduplication of visits by the same person from different browsers, devices and locations. Web analytics systems do not generally deduplicate many of these single user, multiple visits. This is a key step in the production of audience-level data.

From Data to Products

When all this data has been collected, a series of statistical functions is applied to produce monthly numbers for all properties’ unique visitors, page/video views and visit duration.  comScore calls this process Unified Digital Measurement (UDM).  Also integrated into this process are learnings from comScore’s census network, chiefly in the form of Census Informed Targeting (CIT).  CIT might be thought of as corrective weighting for usage of websites and apps, much in the same way that PAMCo’s Audience Measurement for Publishers (AMP) – previously the National Readership Survey (NRS) – is used for weighting panellist demographics.

Using this data, comScore produces a range of online audience measurement products, some of which are UKOM-approved: MMX measures desktop/laptop usage, VMX measures desktop/laptop video usage and MoMX measures smartphone and tablet usage. VMX Multi-Platform, launching in summer 2016, will expand online video measurement to mobile devices.

In comScore’s final UKOM-approved product MMX Multi-Platform (now official UKOM data of record), data from MMX, VMX and MoMX are combined to produce an unduplicated view of people’s usage across all main devices. Again, statistical functions informed by comScore’s census network (in this case a subset of it, known as the ‘Dynamic Panel’) are used to produce final monthly numbers.

If you require more details of these methodologies, please contact UKOM using the query form here.

Contact us

If you have any questions please get in touch and we will be more than happy to help.

© 2018 UKOM Ltd. No reuse without permission.