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Double-blind An experimental procedure in which neither the subjects nor those collecting the data or making evaluations, observations, and providing feedback about the intervention or treatment know which individuals are in the control group and which are in the experimental group.
A non-medical example of such blinding would be an arrangement to test the claims of water diviners and dowsing.
Water pipes could be buried in the ground in the designated testing area and separated from each other at a distance sufficient, according to the dictates of those being tested, to preclude any “interference”. A randomly selected pipe – say one out of ten – could be activated during each trial, that is, set so that only one (or no) pipe had a water flow. Again, on the basis that the water pressure, depth at which the pipes are buried, the situation that any of the pipes may have water flowing on some occasions and not others, and so forth, are conditions which the participants attest do not prevent them from practicing their art.
No one present at the testing area – neither the dowsers and their supporters, nor any of the experimenters and their staff – will be allowed knowledge of the layout of the pipes, or which pipe or pipes may or may not be in operation on any given trial. Such withholding of information about the solution for each trial from all those present enables, in conjunction with the other elements of the experimental design, a fair test of the central claim that dowsers are able to “detect” hidden substances, in this example, water, by ruling out the possibility of “sensory leakage” or cueing as an explanation in the case that subjects were to produce a significant result. (see also: science, control group, experimental research, experimenter bias, randomized assignment, confound/confounding, variable, correlation). Back to: Glossary A-Z
Glossary of selected Judgement & Decision-making, Belief-related, and other Psychology terms A-Z » Labels:
double-blind, double blind, double blinding |