I’ve written before about the risks of debunking myths, as shown by the case of vaccinations, as repeating a myth even when followed up by a list of facts to show its mythical status can make the myth stronger, not weaker:
In a study on perceptions of flu shots, he found correcting myths had the opposite of the desired effect on the most vaccine-skeptical among us. In another study on the measles, mumps, rubella vaccine, he found that myth-busting actually increased some parents’ wariness about the shot.
This ‘backfire effect’ is still novel territory for solid research, but as the British Psychological Society has reported there are some preliminary conclusions that can be drawn from the evidence so far:
It is likely we should avoid restating myths wherever possible and when we must restate myths, we should try to precede the myth with a warning that misleading information is coming up. This can help prevent myths from growing in our minds through mere familiarity.
When we debunk myths we should also try to offer an alternative explanation for false beliefs, to fill the gap left by misinformation.
We should also try to keep our explanations brief, which can help counter the imbalance that often occurs between simple, memorable myths and the more complicated reality.
Those three pieces of advice – don’t repeat the myth, provide an alternative story and keep explanations brief are also very applicable to political argument – such as when Liberal Democrats criticise Labour’s new tuition fees policy, where this points to an approach such as ‘Labour’s tuition fees policy only helps people like their own MPs or bankers – people on wages well above the average. The poorest students, who we should be helping, don’t get helped by Labour’.
UPDATE 2020: However, see what the research is now saying about the backfire effect.