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Placebos in Research

Overview

Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University

Clinical research focuses on the efficacy of treatments for addressing disorders and illnesses. A challenge with this type of research is that participants often have pre-existing beliefs about the treatment, particularly expectations that the treatment will work.

Though it has been practiced around the world for centuries, yoga is a relatively recent fitness craze in the United States with a wide range of alleged benefits, including the belief that it improves one’s creativity. However, it is not always clear whether yoga is actually creating the benefits, like improved creativity, or the yoga practitioner’s expectations are really the cause.

This video demonstrates a two-group design that examines whether a person who believes he or she is doing yoga (but in reality is not) experiences similar benefits to a person who actually does yoga. Specifically, this study looks at whether there is a placebo effect such that merely believing you are doing yoga benefits creativity. 

Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to ensure that the population under study is better represented and the margin of error accompanied by studying human behavior is sufficiently accounted for. Further, human participants for research like this are often readily available and the experiment is quick and inexpensive to replicate. In this video we demonstrate this experiment using just one participant. However, as represented in the results, we used a total of 80 (40 for each condition) participants to reach the experiment’s conclusions.

Procedure

1. Define key variables.

  1. Create an operational definition (i.e., a clear description of exactly what a researcher means by a concept) of yoga-related beliefs.
    1. For the purposes of this experiment, a yoga-related belief is the activation of a participant’s preconceived notions about yoga and its potential benefits that will be manipulated by having the participant do a series of basic stretches that he or she is told is yoga.
  2. Create an operational definition (<

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Results

80 participants were used (40 per condition in a different instance of this study conducted by the researchers). This large number of participants helps to ensure that the results reflect accurate mean numbers. If this research were conducted using just one or two participants, it is likely that the results would have been much different and not reflective of the greater population. The numbers reported reflect the mean number of creative uses for a clothespin participants in each condition listed (Figure 2

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Application and Summary

The use of placebo conditions is particularly common in studies where researchers want to test a medication’s effectiveness. 

For example, DelBello and colleagues2 conducted a study of over 300 adolescents diagnosed with major depressive disorder. Researchers randomly assigned participants to either wear a patch (the selegiline transdermal system [STS] or EMSAM®) or to wear a placebo for 12 weeks. Compared to baseline measurement taken at week 1, both the treatment a

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References
  1. Guilford, J.P. The Nature of Human Intelligence. New York: McGraw Hill (1967).
  2. DelBello, M. P., Hochadel, T. J., Portland, K., Azzaro, A. J., Katic, A., Khan, A., & Emslie, G. A double-blind, placebo-controlled study of selegiline transdermal system in depressed adolescents. Journal of Child and Adolescent Psychopharmacology. 24 (6), 311-317. doi:10.1089/cap.2013.0138 (2014).
  3. Del Re, A. C., Maisel, N., Blodgett, J. C., Wilbourne, P., & Finney, J. W. Placebo group improvement in trials of pharmacotherapies for alcohol use disorders: A multivariate meta-analysis examining change over time. Journal of Clinical Psychopharmacology. 33(5), 649-657. doi:10.1097/JCP.0b013e3182983e73 (2013).
Tags
PlacebosClinical ResearchTherapeutic InterventionsDrug TrialsPlacebo EffectsPerceptionPsychological RolePhysical HealthYogaFitness RoutineBeliefsHealth And WellnessCreativity EnhancementExperimental DesignPerform AnalysisInterpret Placebo ResponsesParticipant BeliefsTwo group DesignPlacebo GroupStretching Group

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0:00

Overview

1:16

Experimental Design

2:23

Running the Experiment

4:44

Representative Results

5:14

Applications

6:36

Summary

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