UK health experts have warned that people "aren't taking the right action at the right time" if they see someone with symptoms of a stroke.
The UK Stroke Association said that acting fast can make a big difference in the outcome for stroke patients.
Research from 2015 shows that almost a quarter of people mistakenly believe that you have to wait for two stroke symptoms before calling an ambulance.
The Australian based Stroke Foundation says people should call an ambulance immediately if someone shows facial weakness, arm weakness or speech problems.
"We know people recognise the signs of stroke but they aren't taking the right action at the right time. A stroke is a brain attack and acting fast makes a huge difference," Stroke Association chief executive Juliet Bouverie said.
"The quicker you act the more of the person you save," she said.
Stroke will affect one in six people worldwide and there are 26 million stroke sufferers globally according to the World Stroke Organisation.
"Stroke is one of the leading causes of death in the country, and the faster someone experiencing a stroke gets emergency treatment, the more chance that person has of surviving and avoiding serious disability," Public Health England's director for health and wellbeing professor Kevin Fenton said.
Stroke is also one of the biggest killers and causes of disability in Australia.
