The report, called Re-evaluating media: What the evidence reveals about the true worth of media for brand advertisers, talked to 116 marketers and agency leaders to identify 12 key attributes for their media campaigns and then used 75 industry studies from the recent past to assess how different media performed against those criteria.
It found "a significant mismatch between industry perceptions and what the evidence says".
The evidence from the 75 industry studies showed TV and radio were best for brand-building on a range of attributes, followed by newspapers, magazines and out of home, and most digital media ranked lower.
This is at odds with marketing decision-makers' perception that online video and social media were second only to TV in importance for brand-building.
Morag Blazey, managing principal of Ebiquity, a media auditing and analytics firm, which advises hundreds of advertisers, said "alarm bells have been ringing for some time" about the effectiveness of digital media.
She added that Ebiquity’s "independent, impartial and robust re-evaluation of the value of media for brand-building" showed "it is time for the industry to re-balance their use of media to optimise advertising budgets".
Radio was particularly "undervalued", according to the report, because the evidence showed it was second in importance for brand-building and yet it ranked only sixth in terms of marketers’ and agency leaders’ perceptions.
Mark Barber, planning director at Radiocentre, the trade body for commercial radio, said: "Personal bias is impacting on [advertisers’] perceptions which impact on which media they’re using."
He said the report is important because it compared "individual media across a range of criteria" and brought all the data together in one place.
"In doing so, we hope that radio will rightfully be considered more often for brand-building campaigns," he explained.
Not bashing digital media
Barber stressed that Radiocentre was not looking to bash digital media channels. "They just need to up their game to demonstrate their effectiveness," he said.
Ebiquity echoed that point about a lack of evidence, saying: "There is little such research for online media and this is something we think the online industry should invest in."
Radiocentre reported earlier this week that commercial radio revenues in the UK hit a record £679.2m in 2017 but Barber said: "I think we’re still hugely undervalued by advertisers. Radio is only about 5.5% to 6% of UK display ad revenues when audio accounts for 18% of time spent with the medium."
Among the findings in the report are:
Targeting is the most important attribute for an advertiser’s media campaign. The evidence shows radio is the top medium for targeting and yet it is ranked among the lowest by perception.
Return on investment is highest for TV and radio but advertisers "overestimate the value of online and social video" for delivering ROI.
Interviewees placed online video and display top for transparent third-party audience measurement whereas "the evidence shows that traditional media comes out top and online video is bottom".
Perception and the evidence were broadly similar when it came to recognising that traditional media is best for triggering an emotional response.
The report runs to more than 30 pages and 12 of them are appendices with details of the evidence.
Barber maintained the analysis, which includes a qualitative weighting of marketers’ and agency leaders’ views as well as quantitative measures, is robust.
"I don’t think anyone’s produced anything like it, with the exception of the IPA’s The Long and The Short Of It."
Ebiquity’s work for Radiocentre follows last year’s study on "short-termism" by Enders Analysis for Magnetic, the trade body for magazines, which also looked at the whole media marketplace.
Enders warned the mix between long-term brand-building and short-term direct response had shifted from an ideal 50-50 balance to 40-60 as advertisers were shifting their spend away from traditional media into online media.
Broadcasters, publishers, OOH and other traditional media owners have been working increasingly collaboratively to assess the effectiveness of advertising as the Google-Facebook duopoly has been sucking up much of the digital growth.