What is the significance level most commonly used in research studies?

The most commonly used significance level in research studies is 0.05. This significance level, also known as alpha, indicates a 5% risk of concluding that a difference exists when there is no actual difference (Type I error). Researchers frequently adopt this threshold because it balances the risks of false positives and false negatives, making it a suitable choice for many fields, including psychology, medicine, and social sciences.

Using 0.05 allows researchers to have a strong enough level of confidence in their findings while still being reasonably stringent. It has become a conventional standard, and many journals and academic fields endorse this significance level for hypothesis testing. By setting a significance level at 0.05, researchers can draw conclusions about their data while also ensuring that their findings are robust and less likely to be due to random chance.