Measures of quality are vital to any systematic study. Such measures, tests, orinstruments exist for all fields. Finding the correct instrument for a study isimportant since the nature of the instrument determines the validity of thestudy. This in turn leads investigators to examine existing studies with the intent toadapt them to a current work, retest their validity with changing times, populations,or conditions, or to establish a newly-designed study within a field and its existingtests and measures.
NOTE: Most of the works that a researcher uses to find appropriate tests areindices that do not contain the tests. Most test literature is protected by copyright andavailable for purchase from the publisher.In some cases, the author is also thepublisher.