This post really follows my previous one (http://tinyurl.com/d6qo5wl ) about asking people to imagine receiving genetic test feedback for weight gain susceptibility and investigating their anticipated reactions. These types of studies are very valuable when not very much is known about a topic, because they provide us with hints about people’s reactions. However, they can only get us so far. At some point, we have to take the leap and expose people to the ‘real’ condition we want to test – in this case, whether receiving personal genetic test feedback in addition to generic weight gain prevention advice will motivate people more to prevent unhealthy weight gain than receiving only generic weight gain prevention advice.
This type of question can be best investigated in an experiment involving two groups, one group that receives the ‘intervention’, and one that is the ‘control’ group. Participants are randomly (by chance) put into either group. We decided to give the ‘control’ group a leaflet with seven memorable tips for weight gain prevention, adapted from a leaflet that has been shown to help people lose weight. The other group – the ‘intervention’ group – also receives the leaflet, as well as their personal genetic test result for weight gain susceptibility. This means both groups receive exactly the same information, the only difference is that the intervention group will know if they are genetically predisposed to weight gain. This allows us to say whether differences between the groups in their motivation to prevent weight gain are due to receiving the genetic test result.
We decided to use approximately 800 first-year university students in this experiment, because the chance of already being overweight at that age is low, but starting university is linked with weight gain (just think of all the late nights, pizza- and kebab feasts!). One month after the intervention, we will send questionnaires to both groups asking about their motivation to prevent weight gain as well as questions about what they have done if they were trying, and whether they followed any of the tips outlined in the leaflet
This is going to be the first study investigating the effects of genetic testing for weight gain susceptibility and will be completed by September 2013. We hope that our findings contribute to the debate about whether genetic test feedback could be used to help motivate healthy lifestyle behaviours.