Demand characteristics and research into drug use

Abstract

Health research makes frequent use of verbal reports; and such reports are usually assumed to be the surface indicants of measurable entities such as attitudes, beliefs, intentions, etc. which reside inside the person. It is our assertion that verbal reports themselves are motivated and variable; they are functional and context-dependent and their meaning and significance are localised. Consequently discourse cannot be treated as if it were fixed and categorical data to be retrieved from memory by asking questions that appear objective or disinterested. A method is postulated, using a social perception analogy with signal detection (SD) theory. The method allows for the assessment of subject criterion, and permits an examination of signal-strength in terms of the researcher's motivation. Data are evaluated in terms of their “robustness”, a measure which derives from the variability of response in different contexts, and under different elicitation procedures. The method requires few assumptions to be made about the “truth” or “falsity” of verbal reports. It focuses on the types of social activities that are performed by utterances and thus on the contextual variability revealed by asking questions in different situations and in different ways. This procedure does not presume a direct correspondence between verbal reports and mental representations.