Thursday, 1 March 2012

A Scale to Measure the Influence of Demand Characteristics in Research Situations

Demand characteristics are cues in a researcher's design, materials, or procedure that allow their research participants to guess their hypotheses. They are a problem because, if participants become aware of the research hypotheses, then they may respond in a way that they believe will confirm the hypotheses in order to be "good" participants and not "ruin" the research (Orne, 1962). These unnatural responses can compromise the ecological validity of the research. In other words, participants do what they think they're supposed to do and not what they would normally do.

To measure the potential influence of demand characteristics, my colleagues and I have created a simple, 4-item scale that measures participants' Perceived Awareness of the Research Hypothesis (PARH; Rubin, Paolini, & Crisp, 2010). The PARH scale is a quick and convenient method for measuring the potential influence of demand characteristics in research situations. An example item is "I knew what the researchers were investigating in this research." Responses are made on a 7-point scale (1 = strongly disagree,7 = strongly agree)