LONDON – Return on investment (ROI) is the holy grail metric for justifying any marketing spend. But whilst surveys can show whether ad campaigns lift brand awareness amongst consumers, proving whether those consumers actually go on to buy anything as a result is trickier – especially in the emerging world of video ad formats.

This is set to change, however, according to video ad tech vendor Videology‘s international product manager Catherine Hallam.

“We’ve had great success in the US with linking not just online purchasing from VOD exposure but offline purchase,” Hallam said during this video interview at Beet.TV’s recent London Video Ad Strategy Summit.

Following a campaign with Kantar, Hallam reports a 47 percent jump in unit sales of a razor brand advertised with online video – a consequence that, previously, may not have been evident. “You can justify VOD for not just branding but also start to prove that it is impacting customers’ journeys in store as well.”

Disclosure: This Beet.TV event was hosted by GroupM and sponsored by Videology.