The researchers believe the tool could be used as an initial screening tool, prioritising potential dementia patients for further tests like brain scans.

They could also highlight effective preventative measures people can take while it's still possible, such as reducing alcohol intake, stopping smoking, and losing weight.

Previous studies suggest up to 40% of dementia cases could be prevented through such action.

"It's well known dementia risk, onset, and prevalence vary by race, ethnicity and socioeconomic status," he said.

"Therefore, we need to evaluate it across more diverse groups of people both within and beyond the UK."

The risk score also doesn't represent a "definitive outcome", the researchers stressed.

Associate professor Sana Suri said the importance of each risk factor varies and some can be treated.

"While over age and APOE confer the greatest risk, modifiable factors such as diabetes, depression, and high blood pressure also have a key role," she added.

Prof Suri said someone with all three conditions will be roughly three times more likely to develop dementia than someone of the same age who doesn't have any.

The findings have been published in the BMJ Mental Health journal.