Demand characteristics: What are they REALLY?

Travis DixonInternal Assessment (IB), Research Methodology, Teaching Ideas

While there's more to understanding psychology than knowing dictionary definitions of terms, they are important building blocks.

I was reading another research methods chapter in a new psychology textbook the other day and despite it’s excellent content in research methodology, it still (I think) mis-defined demand characteristics. 

The most common definition of demand characteristics out there goes something like, “demand characteristics are when participants are aware of the aim of the research and change their behaviour in a way to fit what the researcher expects.” I see this in so many textbooks.

I think this common definition has some essential concepts that are highly relevant to demand characteristics, but by itself it’s a limited and misguided definition. It has the “demand” part of the term, but it’s missing the all important “characteristics.”

Demand characteristics are not an effect, they are parts of a study that can cause an effect. More specifically, they are “…cues in the experimental setting that allow subjects to infer how they are expected to behave.” (Weber and Cook, 1972).  The cues  in the study (i.e. its characteristics) lead participants to formulate an idea of what they think they’re expected (or demanded) to do, and it’s from these cues that they become aware of the researcher’s expectations and change their behaviour accordingly. But of course the cues alone wouldn’t be that significant in discussing threats to internal validity, so there has to be some sort of effect on behaviour which is where the alteration in behaviour is also important in the definition.

So my own definition of demand characteristics used in IB Psychology: A Student’s Guide is: “aspects of a study that might give participants a clue about how they are expected to act. This could confound the results of a study.”

For a more complex version, you can refer to Orne’s definition, in whose work demand characteristics originated (source):  “the totality of cues and mutual expectations which inhere in a social context…which serve to influence the behaviour and/or self-reported experience of the research receiver” (Orne, 1959, 2000).

Except for calling participants “research receivers,” this is a good definition that provides both pieces of demand characteristics: the cues in the study and the effect on behaviour.

Is “demand characteristics” over-taught?

I used to introduce demand characteristics in my early research units but then realized that it was just another term to add to an already terminology laden unit. I then also began to wonder when students would ever independently apply their knowledge of demand characteristics to a study. I’ve argued in another post why I don’t focus on internal validity early in my course and only really for the IA and demand characteristics are a prime example. Are students really going to read the procedures of studies so carefully and in such depth that they’ll be able to identify potential demand characteristics? I doubt it.

What is far more likely is that they’ll rely on understanding someone else’s (e.g. a textbook author’s) evaluation and explanation of demand characteristics in a study and then use this in their own evaluations. But is repeating someone else’s evaluative point critical thinking? Not to me it’s not. I think genuine critical thinking is independent and unrehearsed, which is why I prefer to drip-feed evaluative concepts throughout the course in critical thinking extensions rather than dumping them all in students’ laps in the first two weeks.

My approach to critical thinking is best explained in my theory of surface to deep learning – Trav’s Triad.

I’m not saying it’s not an important concept. It’s arguably just as important as any other related to internal validity and I do try to teach this when students are working on their IAs. But personally, I’d rather encourage my students to spend their efforts mastering understanding and application of studies, followed by mastering the application of concepts related to external validity in evaluating research before they move on to things like demand characteristics.

ORNE M. T. (1959). The nature of hypnosis: artifact and essence. Journal of abnormal psychology58(3), 277–299.
Orne MT, Whitehouse WG. Kazdin AE, editor. Demand characteristics. 2000. pp. 469–470. editor. Encyclopaedia of Psychology. Washington, D.C.: American Psychological Association and Oxford University Press.

Weber, S. J., & Cook, T. D. (1972). Subject effects in laboratory research: An examination of subject roles, demand characteristics, and valid inference. Psychological Bulletin, 77(4), 273–295.