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‘23 and ½ h’ goes viral: top 10 learnings about making a health message that people give to one another
  1. Michael F Evans
  1. Correspondence to Michael F Evans, Family Medicine and Public Health, University of Toronto/Health Design Lab Scientist, Li Ka Shing Knowledge Institute, Staff Physician, St Michael's Hospital, Toronto, Canada; mfe5{at}

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In my day job as a Family Physician, I often wonder, ‘Is this bacterial or viral?’ In my other job, where I try to innovate on how to engage patients in more meaningful ways, my question is slightly different: ‘How can we make this viral instead of bacterial?’

A Healthy Virus

‘23 ½ hours: what is the single most important thing you can do for your health?’1 (referred to as ‘23.5’ below and figure 1) is a video I posted on YouTube in December 2011. My objective in making the video was twofold: 1) to experiment in creating a new way of engaging patients about their health and 2) to answer what is the most important thing we can do for our health? I am a family doctor, not a sports medicine expert, so I was intrigued that my answer is exercise. I was intrigued as activity is something I ask my patients about but it is not something I have systematically assessed and counselled upon in my practice in the same way as other clinical problems such as blood pressure or cholesterol.

Like any good virus, my primary objective was spread. At the time of writing (22 February 2012) 23.5 has had 2 million people sit down and view it, has averaged about 25 000 views a day, generated over 1000 comments and has been ‘liked’ by over 16 000 people (and ‘disliked’ by 190). It has already been translated by the ‘community’ into Spanish and …

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  • Competing interests None.

  • Provenance and peer review Not commissioned; externally peer reviewed.