"One of the things that is important in understanding how advertising works, is to separate the consumer relationship with the medium from the consumer relationship with advertising in the medium. And very often people look at time spent as a leading indicator of advertising engagement, or advertising wantedness," Ellen Oppenheim, CMO of the Magazine Publishers of America told MediaDailyNews, explaining why the MPA's new "Ad Value Per Minute" analysis is a relevant measure for advertisers and agencies to use when planning and buying media.

Raw time spent analyses, she said, are about consumer usage of "the medium, not the advertising" within them. To get at the relative value of time spent with advertising in the major media, the MPA factored a well-regarded analysis conducted by a respected third party, ad impact scores created by consulting firm Deloitte ("State of the Media Democracy" Study, 2008), and incorporated it into a new "Time/Ad Impact Ratio" for the major consumer media.

On that basis, magazines index with more than twice the impact of TV, online or radio, and are actually considerably higher than printed newspapers too (see table below).

Oppenheim said other impact scores could be substituted with the Deloitte data, and it would show similar patterns of stronger relative advertising impact of magazines.

She acknowledged that the studies are all surveys based on consumer perceptions about media, and not necessarily behavior, and therefore are not a "gold standard.

"No one is suggesting this is a currency," she said, adding that the analysis nonetheless is a good way of factoring raw time-spent analyses of media. One that is receiving considerable attention in recent weeks, is a highly regarded study conducted by Ball State University for the Nielsen-funded Council for Research Excellence. That study, which directly observed how consumers use media, initially reported findings only on the major "screen-based" media, such as TV, online, mobile, and gaming platforms. But the findings are sparking a new round of interest in advertising circles about the relative value of time spent with all media, especially as the industry struggles through an economic recession and prepares for another upfront television sales season.