Abstract
Operationally defined variables in psychological research. The purpose of this paper is to remark the importance to use operational definitions, sometimes forgotten in psychological research. Several approaches have emphasized the importance of operational definition, centering interest in two of more important variables in any experimental research: Independent Variable and Dependent Variable, but falling into basic oblivion: Extraneous Variables. Our proposition is to extend operational definition concept to Extraneous Variables, naming it as Control Operational Definition, and meaning it as: "conceptual and operative definition of a concrete Extraneous Variable, including the activities that researcher must do in order to obtain a more effective experimental or statistic control of extraneous variables in experiment".
