Known as the β-score, this method of measuring media memorisation indicates how many people remember a message after the first exposure.
The score shows that media, and not only the message, have a different level of memorisation. An overview of all media shows that cinema has the highest score (75%), followed by much lower scores for TV (17%), newspapers & magazines (10%) and posters (6%).
A separate study on the various types of mail shows a very interesting comparison: addressed (with name and address) mail scores 61% and door drops 27%.
The β-score is part of media-planning as it provides data about the wear-out of a campaign. In other word, how long should a campaign run. Using media with a high β-score will prolong the effect of a campaign. And these media will optimise the overall effectiveness of a campaign as this example shows.