When the US Preventive Services Task Force (USPSTF) and the American College of Obstetricians and Gynecologists (ACOG) changed their recommendation for breast cancer and cervical cancer screening from every year to every three years, many doctors and patients were reluctant to follow the new guidelines.

They shared stories and personal experiences that seemed to conflict with this advice, urging their friends and colleagues to keep getting screened every year.

Why do people ignore evidence-based recommendations in favour of personal stories, and can they be persuaded to listen to evidence instead?

New findings from a preregistered study suggest that asking people to set up a long-term screening schedule may help them follow evidence based recommendations, rather than personal stories.

The results appear in the journal Social Psychological and Personality Science.

"Even though many people think that it's probably a good idea to follow evidence-based guidelines when making medical decisions, our human minds sometimes have a hard time weighing these guidelines as much as we should--especially when we hear a vivid anecdote," says lead author Alison Ledgerwood (University of California, Davis). "In this study, we tried to leverage the idea that people are better at relying on general guidelines--rather than vivid, specific stories--when they focus on the future."

In their study, 224 women between the ages of 21 and 55 were asked to imagine they have a gynecological appointment coming up the in the next week. The participants were randomly assigned to one of two groups.

The first group was simply asked whether they'd do a screening at their upcoming appointment.

The second group was given an intervention that asked them to decide on a screening schedule for the next ten years.

Both groups were provided with USPSTF's recommendation for their age group as well as a personal anecdote about screening.

In the first group, only 31.6% of the women made a decision that reflected USPSTF's evidence-based recommendations.

But in the second group, when participants were asked to choose a screening schedule for the next 10 years, 62.6% of women made a decision that reflected the evidence-based recommendations.

In other words, asking participants to focus on the future approximately doubled the number of people who followed the USPSTF guidelines.

While in the studies women saw both evidence-based information and a personal story that contradicted the evidence, in the real world, they might or might not encounter both of those pieces of information.

Ledgerwood and her colleagues would like to see a field study to test these results in real-world scenarios.

They would also like to see if the results would replicate if participants were presented with just the guidelines, without a conflicting anecdote.

If the results of future studies produce similar results, then they would point the way to an intervention that could be both easily implemented and effective for promoting evidence-based recommendations.

Source: Society for Personality and Social Psychology