Australians are overwhelmingly positive - at least when it comes to their blood type.
That's according to a landmark study from Australian Red Cross Lifeblood senior researcher Dr Rena Hirani, published on Monday in the Medical Journal of Australia.
She looked at more than 1.3 million Australian blood samples from 2019, finding 85.9 per cent were positive blood types.
The most prevalent types were O+ (38.4 per cent) and A+ (32 per cent), while AB- was the least common at 0.5 per cent.
Dr Hirani also looked at data from 490,491 first-time blood donors. About 83.8 per cent had positive blood types, an increase from 81 per cent in 1993-94 when the last study was conducted.
Dr Hirani said the high levels of migration from South East Asia, China and India over the past 10 years was reflected in the data.
"Blood types are determined by your genetic background, much like your skin and hair colour," Dr Hirani told AAP.
"We've seen higher proportions of those blood groups in those countries that are coming into Australia.
"They are more likely to be RhD+ (Rhesus D blood group) so it's wonderful to see those communities reflected in our blood works."
Dr Hirani said the new Australian analysis was the most comprehensive of its kind, as the 1994 study only looked at blood donor data.
She said the new information would ensure Lifeblood's donor list could support a growing population.
"We're very lucky in Australia that generally we are meeting all of our blood requirements," Dr Hirani said. "But we want to continue to do so into the future.
"We need this information to make sure we can diversify the donor panel."
