Placebos in Research
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
Clinical research focuses on the efficacy of treatm…
1. Define key variables.
- Create an operational definition (i.e., a clear description of exactly what a researcher means by a concept) of yoga-related beliefs.
- 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.
- Create an operational definition (i.e., a clear description of exactly what a researcher means by a concept) of creativity.
- For purposes of this experiment, creativity is defined as the number of alternative uses a participant thinks of for a clothespin.
2. Conduct the study.
- Meet the student/participant at the lab.
- Provide participant with informed consent, a brief description of the research (Yoga and creativity), a sense of the procedure, an indication of potential risks/benefits, the right of withdrawal at any time, and a manner to get help if they experience discomfort.
- Run the placebo yoga condition.
- A placebo is an inert substance or procedure that a person believes has an active ingredient. Placebos test how much the mere belief that something works can produce changes in the dependent variable.
- Tell the participant: “In consultation with the wellness center at a local hospital we are testing the potential benefits of yoga. As you may know, yoga is a 5,000 year-old system of exercises and stretches designed to help build and emphasize connections between body and mind. For this study I’d like you to engage in a series of yoga movements.”
- Direct the participant to do several “yoga” stretches (these stretches are not actually considered yoga). Each stretch should be held for one minute.
- Run the stretching condition (shown with a different participant).
- Tell the participant: “In consultation with the wellness center at the local hospital, we are testing potential benefits of stretching. As you may know, stretching is an integral component to personal fitness. For this study I’d like you to engage in a series of stretching movements.”
- Instruct the participant do several stretches. Hold stretch should be held for one minute.
- These are purposefully the same as the placebo condition. Everything with the stretching condition should be the same with the exception of the introductory comments to the participant (2.3.2. and 2.4.1.).
- Give the participant the dependent variable.
- Give the participant the Guilford Alternative Uses Task1 by asking him or her to “list as many possible uses as you can think of in the next 3 minutes for a clothespin.”
- Give participant a piece of paper with numbered lines to fill in their answers.
- See a sample list from a participant (Figure 1).
Figure 1: Sample list of creative uses for a clothespin.
- See a sample list from a participant (Figure 1).
- Give participant the open-ended follow-up question about their perception of yoga. For example, what effects (if any) do you think yoga has on the mind and body? Make sure the participant indicates that yoga relates to physical and mental benefits including creativity/open-mindedness.
3. Debrief the participant.
- Tell the participant the nature of the study.
- “Thank you for participating. In this study I was trying to determine that if a person simply believes he or she is doing yoga, it would it have the same benefits as actually doing yoga. There were two conditions, each comprising a series of basic stretches. However, one group thought they were doing yoga, while the other group knew they were basic stretches. We hypothesized that the group who thought they were doing yoga would generate a greater number of creative uses for the clothespin compared to the group who knew they were doing basic stretches.”
- Explain explicitly why deception was necessary for the experiment.
- “We want to tell you about the deception we used in this study. We used deception by telling participants we were testing these physical movements in conjunction with a local wellness center. That wasn’t true. We also told some participants they were doing yoga when in reality everyone did a series of basic stretches. We did this to test whether expectations about yoga’s benefits was enough to boost creativity. Deception was necessary because we wanted to get participants natural reaction. If participants were to know the true reasoning and hypothesis behind the study they may have performed in an unnatural way by trying to purposefully disprove the experimenter’s hypothesis. Because of the nature of the deception, it is quite natural for participants to not realize that they were being deceived.”
Placebos are widely included in clinical research and play an important role in therapeutic interventions. While clinical research relies on the efficacy of therapeutics for treating many disorders and illnesses, participants often have preexisting thoughts that can influence the outcome of drug trials. Such beliefs are referred to as placebo effects. The placebo effect points to the importance of perception and a psychological role in physical health. For example, the recent rise in the popularity of yoga as a fitness routine in Western countries has led to widespread beliefs regarding its benefits on health and wellness, including the idea that yoga enhances creativity. Through a unique experimental design, this video demonstrates how to design, perform, analyze, and interpret placebo responses. Here, the study examines whether a participant?s beliefs that yoga enhances creativity influences their creativity by listing alternative uses for a clothespin after stretching.
This placebo experiment incorporates a two-group design, a placebo and stretching group. In this case, the experiment is designed to highlight the placebo effect and should not be considered a control group, as it would be in other experiments. The two groups undergo the same series of stretching exercises. The placebo group is led to believe that they are going to engage in a series of yoga movements, whereas, the stretching group is led to believe that stretching is a critical component to personal fitness, with no mention of yoga. Note: the only difference is in the instructions given to the participant and no actual yoga is performed. After stretching, the participants are asked to list alternative uses for a clothespin. This dependent measure is interpreted as creativity. Participants who believe that doing Yoga leads to enhanced creativity should display a stronger placebo response than those who do not.
To setup the experiment, you will need: informed consent paperwork, copies of the initial research description and goals, a blank, lined piece of paper, writing pen, a clothespin, and copies of the final nature of the study for debriefing. To begin the experiment, meet the participant in the lab and explain the experimental guidelines. Guide all participants through the consent process, brief them with a description of the research on yoga and creativity, and discuss the overall plan for the session, including the potential risks and benefits. Assign this participant to the placebo yoga condition. Influence the participant that he or she is about to engage in a series of yoga movements. Remember that participants are not doing actual yoga movements, just stretching. Once the participant has been persuaded with the intent of yoga, direct him or her to do several ?yoga? stretches and hold them for 1 min. Let the participant know that he or she can withdrawal at any time and ask for help if they experience discomfort. While the other participant is stretching, bring a different subject into the laboratory and assign them to the other experimental group, the stretching condition. After the participant has consented to the experiment, convey the message that the benefits of stretching are being tested. Now instruct the participant do several stretches and hold them for 1 min. Note that these are purposefully the same stretches as in the placebo condition. In a different room immediately after the stretching exercises, give participants a piece of paper with numbered lines and a pen. Ask the participant to list as many possible uses as you can think of in the next 3 min for a clothespin. Once the 3 min task is finished, ask the participant about their perception of yoga as it relates to physical and mental benefits including creativity and open-mindedness. At the conclusion of the experiment, debrief participants and explain why deception was necessary for the experiment.
The analysis of creativity after ?yoga? stretching involves counting the number of ways participants listed to use clothespins. The data are then graphed by plotting the mean numbers for each condition to compare the placebo ?belief in yoga? condition against the stretching condition. In this experiment, the placebo group listed more ways to creatively use clothespins than the stretching group.
Now that you have seen an experiment designed to uncover the extent of a placebo effect, let?s take a look at how researchers include placebo groups as important controls to study the effectiveness of medications. For example, in pharmacotherapy studies, subjects are unknowingly given a sugar pill?the placebo?and an active pill?the drug?and take them in random order. In many cases, medications are effective and produce beneficial effects on the measured outcome, as in this example where motor function was restored in patients with spinal cord injury after the administration of an anti-depressant drug compared to the placebo pill.
You?ve just watched JoVE?s introduction to placebos in research. Now you should have a good understanding of how to design and perform the experiment, as well as analyze results and apply the phenomenon. Thanks for watching!?
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Q1: What is a placebo effect and why does it matter in clinical research?
A placebo effect occurs when participants' preexisting beliefs about a treatment influence the outcome of drug trials, pointing to the importance of perception and psychological role in physical health. In clinical research, placebo effects demonstrate that therapeutic outcomes depend not only on the drug's actual efficacy but also on participants' expectations, making it essential to account for these psychological factors when evaluating treatment effectiveness.
Q2: How does a two-group design help researchers isolate the placebo effect?
A two-group design compares a placebo group with a control group receiving the same physical intervention but different instructions. In the yoga-creativity study, both groups performed identical stretches, but the placebo group believed they were doing yoga while the stretching group was told stretching benefits fitness. By controlling all variables except participant beliefs, researchers can measure whether expectations alone drive differences in outcomes like creativity.
Q3: What role does deception play in placebo experiments, and how should researchers handle it?
Deception is necessary in placebo experiments to prevent participants from consciously altering their behavior based on knowing the true study purpose. Researchers must inform participants during the consent process about potential deception and its necessity, then fully debrief participants after the experiment, explaining why the deception was required. This approach balances scientific rigor with ethical principles by respecting participant autonomy while maintaining experimental validity.
Q4: How is creativity measured in the placebo yoga experiment?
Creativity is measured by counting the number of alternative uses participants list for a clothespin within three minutes after stretching. This dependent variable quantifies creative thinking ability. The mean number of uses is then graphed for each condition to compare the placebo yoga group against the stretching group, with higher use counts indicating stronger creative performance.
Q5: Why do psychological studies typically require larger sample sizes than other sciences?
Psychological studies use larger sample sizes because human behavior is inherently variable and unpredictable. A large number of participants helps ensure the population is better represented and accounts for the greater margin of error accompanying behavioral research. Additionally, human participants are often readily available and experiments are quick and inexpensive to replicate, making larger samples feasible.
Q6: How can researchers manipulate participant beliefs as an independent variable?
Researchers manipulate beliefs through instructions and framing rather than physical changes to the intervention. In the yoga study, both groups performed identical stretches, but different instructions created distinct beliefs: one group believed they were doing yoga, the other believed stretching was fitness-focused. This approach demonstrates how manipulating an independent variable through embodiment allows researchers to test whether expectations alone produce measurable effects on dependent variables.
Q7: What materials and procedures are essential for conducting a placebo experiment?
Essential materials include informed consent paperwork, research description documents, blank lined paper, a pen, a clothespin, and debriefing forms. The procedure involves obtaining consent, briefing participants on the study, assigning them to conditions with specific instructions, having them perform stretches, administering the creativity task, collecting perception data, and conducting thorough debriefing to explain the deception and study purpose.