Power of study can be increased by

Power of a Test: – Is probability of rejecting a Null hypothesis when a predetermined clinically significant difference is indeed present – Measures the ability to demonstrate an association, when one really exists – Power of a statistical test: 1 – b ( 1 – probability of Type II error) – Power of a statistical test is complimentary to b (probability of Type II error) – Power of a statistical test is a numeric representation of: Sensitivity – Power of a statistical test can be increased by: 1. Increasing the no. of subjects in a trial (sample size) 2. Reducing b (probability of Type II error) 3. Increasing sensitivity – Power of a statistical test is also used for calculation of sample size for a study