The public's perception of the plausibility of dementia risk factors is not influenced by scientific evidence

Background/Aim: The public know little about risk factors for dementia. The aim of this study was to explore belief structures underlying how plausible risk factors for dementia appear to the general public. Methods: Two thousand members of the Australian public were surveyed by telephone on their beliefs regarding dementia risk factors. Factor analysis was performed on 17 modifiable behaviours that were rated by participants as increasing, not changing or decreasing the risk of dementia. Results: Three factors were obtained - Health and Lifestyle, Activity, and Nutrition. Items loading on the Health and Lifestyle factor were management of cardiovascular risk factors, drinking more water, reducing stress, coffee and tea, and alcohol intake. Items loading on the Activity factor were mental, physical and social activity and getting out and about more. Items loading on the Nutrition factor were eating foods high in omega-3 fatty acids, antioxidants and estrogen, using non-aluminium cookware and taking vitamin and nutritional supplements. Factors were characterised by similarity of items, rather than level of scientific evidence of an association with dementia. Factor scale scores differed according to sociodemographic characteristics. Conclusions: The public do not process dementia risk factor information based on level of scientific evidence.