Most texts (e.g., Straus, Richardson, Glasziou, & Haynes, 2005) on evidence-based practice (EBP) focus solely on EBP metrics (e.g., sensitivity, specificity, positive likelihood ratio, etc.) for the critiquing of tests. However, it is also important for EBP practitioners to consider traditional or classic measures such as reliability and validity. These measures quantify the worth of tests by determining their accuracy and the consistency. By identifying tests that exhibit strong reliability and validity, clinicians can identify tests that are candidates for use in their own clinical context with their own clients (Tickle-Degnen, 2002). Moreover, as will be addressed in future tutorials, selected classic measures can be used to validate the use of tests for various purposes. This tutorial will address three classic measures of validity, reliability, and standard error of measurement.