Manipulation Checks in Experimental Research


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Clinical Trials		< back		8 of 13		next >

Clinical trials or "clinical experiments" also need manipulation checks to make sure that the program or intervention was done properly. These are almost always incorporated directly into the study as it may be difficult for participants to remember specific aspects of the study design during the debriefing.

		Manipulation checks can be quite sophisticated. Some drug trials use pill bottles with a microchip in the cap that records how many times the bottle has been opened. This has been shown to be a better measure of medication compliance than the participant's self-report. Education programs with information posted on the Internet can use "counters" to determine how many times the participant accesses the site, what is read, and how much time is spent reading the material. These methods may be beyond the reach of most researchers. Let's look at a manipulation check used in a program evaluation.