MedicalStat

## Calculate Power and Sample Size

Alpha (α) is the significance level, often 0.05 (5 %). It is the same as the risk of making a Type 1 error (rejecting a true null hypothesis).

Beta (β) is often 0.20 (20 %). It is the same as the risk of making a Type 2 error (accepting a false null hypothesis).

1 - β is the power of the study and is often 1 - 0.20 = 0.80 (80 %).

The power of a study is the probability of rejecting a false null hypothesis.

Decimals: