Boffins have devised a formula for the perfect business presentation – and it should be no longer than 45 minutes.
Yawns and glazed eyes could become a thing of the past after the calculation took into account factors ranging from content to engagement.
Ed Gruwez, founder of presentation design company ‘To The Point At Work’, calculated that the quality of any presentation depends on the exact quantities of “cognitive load”, “message strength”, and “handle effect”.
The length of presentation plays a “crucial role” – ideally between 15 and 45 minutes – as does the relevance of content and the appropriateness of the slides or the type of interaction.
Relevance of content and the appropriateness are also critical, as are the slides or the type of interaction.
But too much or too little of any one component can lead to “presentation passivity” – where audiences switch-off and leave without absorbing any information.
The formula calculated by Gruwez – CEO of agency Ogilvy Internal Communications – is the culmination of more than two years of research and study.
In the formula, ‘E’ represents Presentation Effect, ‘RT’the Total Time, ‘KMS’ the Perceived Message Strength, ‘HE’the effect of ‘story handles’, ‘SA’ the Slide Design Appreciation, ‘MS’ the Message Synchronicity and ‘CLj’ the Cognitive Load of slides.
Gruwez, who in addition to organising presentation training events around the world is also a respected author published by FT Publishing, evaluated over 750 corporate presentations.
He also interviewed 273 employees from multi-national businesses including JP Morgan, KPMG, Coca Cola, Merck, Microsoft, Accenture, Volvo, and Astra Zeneca – across 21 countries.
He found that 45 per cent of presentations are “much too long”, and that in 47 per cent of cases, audiences learned “virtually nothing whatsoever”.
“The effect drops very quickly if a presentation is too long,” he said. “This ideal length depends on a number of other factors, such as the interest of the audience in the subject, the number of key messages and the number of ‘handles’ used in a presentation.
“But most presentations, when cut by half, will yield much more effect.
“As a general rule, depending on the number of key conclusions and the interest of the audience, the ideal presentation should last between 15 and 45 minutes.
“It’s often better to cut down drastically the length of the presentation and leave more time for discussion.”
Less than a quarter of all presentations produce a marked effect, despite employees spending an average of nine hours a week delivering, preparing, or sitting through them.
Probably the most striking conclusion of Gruwez’s research is that the fluency of the presenter is much less important than generally assumed.
Gruwez, whose new book ‘Presentation Thinking & Design: Create better presentations, quicker’ hits the shelves this week, admits that his research is still in its preliminary stages and that the equation may not withstand the scrutiny of the scientific community.
He said: “Much more research is needed in this field, but the basis of the formula seems to be correct – that is, presentations which do not balance the correct quantities of each ingredient will cause boredom, passivity and a general feeling among the audience that the presentation was a complete waste of time.”