Hypotheses 2x2 Table of study hypotheses Null hypothesis (H0) login to view 2 more bullets Alternative hypothesis (H1) login to view 2 more bullets Type I Error (False Positive) Stating there is an association when none exits login to view 1 more bullet α = probability of type I error p = probability that results as or more extreme than those of the study would be observed if the null hypothesis were true login to view 1 more bullet Type II Error (False Negative) Stating there is no effect when an effect exists login to view 1 more bullet β = probability of type II error Power (True Positive) Probability of correctly rejecting null hypothesis login to view 1 more bullet Power depends on login to view 4 more bullets True Negative Probability of correctly accepting null hypothesis Confidence Interval Range of values associated with a confidence level indicating the likelihood that the true population value of a parameter falls within that range login to view 2 more bullets Confidence interval is calculated from statistics generated from the studied data Smaller confidence intervals suggest better precision of the data Larger confidence intervals suggest less precision of the data If confidence intervals of 2 groups overlap, there is no statistically significant difference A Priori Versus Post Hoc Analysis A priori comparisons login to view 2 more bullets Post hoc analysis login to view 5 more bullets