A new online tool which claims to predict an individual's likelihood of death with 80% accuracy has been launched.

The test, for people aged between 40 and 70, uses a number of questions to judge their risk of dying in the next five years.

It is based on research into half a million people carried out by two Swedish scientists, using more than 600 lifestyle variables to assess what can best predict mortality risk.

They narrowed it down to 13 lifestyle questions for men and 11 for women, with the researchers claiming it is 80% accurate.

Take the test www.ubble.co.uk/ 

The researchers also found that self-assessment of health proved to be the most accurate indicator of how likely men were to die, whereas previous cancer diagnoses were the most accurate for women.

A habit of smoking was found to be the best way to judge whether someone will die, once disease and serious disease or disorder were excluded.

Dr Erik Ingelsson, who was involved in the study, said: "The fact that the score can be measured online in a brief questionnaire, without any need for lab tests or physical examination, is an exciting development.

"Of course, the score has a degree of uncertainty and shouldn't be seen as a deterministic prediction.

"For most people, a high risk of dying in the next five years can be reduced by increased physical activity, smoking cessation and a healthy diet."

It is hoped the test will help raise awareness among the public about their health, as well as aiding doctors and being used as a guide for public health policy.

Once users have finished the questionnaire, they are presented with a so-called Ubble age based on their answers.

A lower age than their own indicates good health: a higher one, less so.

Users also receive a risk of death expressed as a percentage.

This indicates how many people out of 100 of the same age and with similar answers will die within the next five years.

Dr Ingelsson added: "In general, if your Ubble age is higher than your actual age, it could raise concerns and provide some incentive for lifestyle change.

"Each question is representative of something - the number of cars owned by someone is most likely a proxy for their social-economic group.

"Walking fast would not decrease your risk of dying, but if you are walking slowly it could be a predictor of bad health - such as heart disease."

The data for the project came from the UK Biobank, an online database of 500,000 people and their health conditions.

A total of 498,103 participants in that database were used for the study, which began in 2007.

More than 8,500 people had died by the time a follow-up was done in 2012.

Conclusions were drawn by comparing the risk profile of those who died with those who did not.