There is a distinction that one learns about on the first day of a course in psychological research methods. It is the difference between internal and external validity. Internal validity is ...

The three-step process shown in Table 2 can be used to assess the validity of a study's findings and determine if they are relevant to readers' practices. The first step in establishing validity is to ...

Objective To produce a best evidence synthesis of the clinical effects of topical glyceryl trinitrate (GTN) in the treatment of tendinopathies. Design A systematic review of published randomised ...