Shorter form ads can at least match the performance of 15-second commercials on various important metrics for brands, according to a paper published in the Journal of Advertising Research (JAR).

The analysis was written by Duane Varan (from research firm MediaScience) and Magda Nenycz-Thiel, Rachel Kennedy and Steven Bellman (from The Ehrenberg-Bass Institute for Marketing Science, a unit of the School of Marketing at the University of South Australia).

Eleven ads were used across three studies that involved 722 participants, with seven- 15-, 30- and 60-second variants of the same commercials being tested for brand recall, ad liking, brand attitude and biometric measures.

“In the current research, seven-second advertisements were just as effective as 15-second advertisements (i.e., twice their length), with unaided brand recall as the measure of effectiveness,” the authors wrote.

“Seven-second advertisements delivered 60 percent of a 30-second advertisement’s brand recall, even though they were less than a quarter of the length.”

The results of the three studies also showed that short advertisements can “deliver effectiveness efficiently, because advertisement length has diminishing returns”.

In line with what is termed a “template theory of memory”, they suggested that “most of the effect of advertisement length on advertisement awareness is delivered by the first five seconds of exposure”.

Their study, entitled The effects of commercial length on advertising impact: What short advertisements can and cannot deliver, provided further insights for marketers.

One example: commercial length registered a “diminishing-returns effect” on advertisement liking, although this impact was “smaller and harder to detect” than other outcomes.

The biometric indicators employed in the research also confirmed that longer ads “were better at taking viewers on an emotional journey with more ups and downs”, as measured by smiling activity and skin conductance.

Another strategic learning involved the use of seven- or 15-second ads as “reminders” of longer ads that run for 30 or 60 seconds.

And the study replicated previous analysis in finding that “seven-second advertisements were as effective as 15-second advertisements as reminders of longer advertisements”.

Sourced from Journal of Advertising Research; additional content by WARC staff