The average Australian spends more than five hours watching YouTube every month.
With such high viewership, it's no surprise that interest groups are reaching out with YouTube to try to change people's behaviour, including well known campaigns such as Beyond Blue's Man Therapy and Tourism Australia's Best Jobs in the World. But how successful are they?
It's well established that television and movies can influence audience behaviour. For example, medical dramas can increase the number of people signing up for organ donation and encourage women to get breast cancer screenings, while movies that feature smoking increase the number of teenagers taking up smoking.
There's even a Hollywood charity dedicated to using television and films for promoting public health messages. However, YouTube videos are much shorter than television shows or movies, meaning that people have less time to become involved and persuaded to change their behaviour.
In our study we looked at whether a single viewing of a YouYube video could influence a person's behaviour a month later. More specifically, we looked at whether watching a 50-second YouTube clip could encourage pet fish owners to regularly clean out their aquariums.
Why pet fish? In many behavioural studies results can be biased by outside influences. If we studied exercise or smoking the participants would have been exposed to similar advertising campaigns elsewhere and might be tempted to lie about their behaviour to feel better about themselves. We were fairly confident that fish owners wouldn't come across any other videos on cleaning fish tanks.
Fish are also the forgotten family pet. Just like cats and dogs, fish are intelligent, long-lived and can feel pain, but you would never flush your dead cat down a toilet or win puppies at carnivals.
With 1.5 billion pet fish sold globally every year, it's time we started taking better care of them and regularly cleaning out an aquarium is one of the most effective ways to keep your fish healthy.
Nearly 200 fish owners took part in our online experiment. After answering a few short questions about keeping fish and how often they cleaned their tank, they were randomly assigned to one of three groups.
Two of the groups were shown different videos designed to improve their tank cleaning habits, either a sad video about pets dying or a funny video of fish pooing. The remaining control group were shown no video at all.
One month later, they were asked again how often they cleaned their tanks and what they remembered about the video.
What they remembered
Initially, it looked as if watching the YouTube video made no difference to their behaviour. About a third of people cleaned their tank more often after the experiment, a third less often and a third stayed the same.
However, a closer examination revealed that the results were slightly more complex. People who watched a video but did not improve were already doing the right thing and cleaning out their aquariums regularly.
So, rather then being unaffected by the video, they simply didn't have room for improvement. But for the one-quarter of respondents who agreed they needed to improve, the videos made a big difference.
The group of owners who said they needed to improve but did not see either YouTube video actually got worse over the following month. Half cleaned their tank the same number of times and the other half cleaned their tank less often. None of the participants in this group improved their habits.
By comparison, 60% of fish owners who intended to improve and watched a YouTube video started cleaning out their tanks more often. Only 6% cleaned their tank less after watching the video.
Make 'em laugh to remember
When it comes to remembering the message, comedy appears to beat tragedy, with 88% of people who saw the funny video recalling it after one month compared to 60% who recalled the sad video.
Our results suggest that YouTube videos can affect a person's behaviour, if only by reinforcing what you already intended to do. For example, a YouTube video encouraging people to quit smoking won't help people who don't smoke, and won't stop determined smokers. But it could help people who were thinking about quitting to start taking action.
So for people thinking of making a YouTube video there is some evidence to suggest that a funny video will be remembered better, which is possibly why Melbourne's Metro Trains Dumb Ways to Die was a YouTube hit despite dealing with a serious topic.
Our results, while promising, represent a small sample and may not apply to all topics or all groups of people. YouTube is an important feature of modern life and more research needs to be done to determine its full potential to influence our behaviour.
Explore further: PSY and Ylvis top YouTube 2013 video hit list
More information: This is an edited version of Miriam Sullivan's presentation "Can we change behaviour using YouTube?", delivered today at the Australian Science Communicators national conference in Brisbane.