Nielsen’s Four-Screen Ad Deduplication methodology will allow media buyers to better compare YouTube’s reach to linear TV advertising buys.

The methodology will be available on Nielsen Total Ad Ratings, before being a key part of Nielsen’s forthcoming cross-media measurement platform Nielsen One.

The latest announcement will see Nielsen add CTV to existing computer, mobile and linear TV deduplication to Total Ad Ratings to help media buyers delineate linear television and CTV inventory.

YouTube accounts for greater than 50% of ad-supported streaming watch time on CTVs among people aged 18 and over in the US, according to Nielsen Streaming Platform Ratings.

Kim Gilberti, senior vice-president, product management, at Nielsen, said: “Four-screen measurement is a critical step toward Nielsen One, as it provides the comparability necessary to produce a trusted, deduplicated number across platforms that enables clients to better understand reach, manage frequency and verify the audiences of their media buys.

“As consumer engagement across platforms continues to converge, digital measurement must provide continuous and comparable metrics across all channels.”

Debbie Weinstein, vice-president, global advertiser solutions, at Google and YouTube, said: “In a converged world, customers need a complete picture of their ad spend across all screens.

“Nielsen enabling advertisers to compare YouTube’s reach across mobile, desktop and now CTV to TV is a tremendous step towards their vision for Nielsen One, and we look forward to their continued efforts to bring cross media measurement to the industry.”