The maturation threat can operate when biological or psychological changes occur within subjects and these changes may account in part or in total for effects discerned in the study. For example, a ...

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 ...

Experimental mortality Description of data analysis for study dropouts, or use of intention-to-treat analysis or appropriate statistical analysis Demographics and clinical outcomes tables: statistical ...