Friday, August 14, 2015

When Does Choosing a Treatment Matter?

In the United States, many provisions of the Affordable Care Act (also known as Obamacare) is the law of the land.  Opponents of the law have been concerned that it will ultimately reduce some people’s options for the care that they receive, even as it increases the number of people who are insured overall.  
The long-term implications of this law for health care are not at all clear, but there is an interesting question about the role of options in health care.  Does it matter if people have a choice among a set of treatment options?
This question was explored in a paper in the October, 2013 issue of the Journal of Personality and Social Psychology by Andrew Geers, Jason Rose, Stephanie Fowler, Heather Rasinski, Jill Brown, and Suzanne Helfer.  They were interested in whether the option to choose a treatment would influence people’s perception of pain and discomfort.
In one study, participants came to a lab set up to look like a medical testing facility.  Prior to the experiment, the participants had filled out a questionnaire measuring how much they like to have control over situations in their lives.  When they arrived at the experiment, they were told that they would be placing a hand in very cold water.  Then, they were shown two jars of creams.  One group was told that these creams were two different kinds of protection against the cold.  One cream was described as warming the hand to protect like a glove, while the other was described as blocking pain receptors.  A second group was told that the creams were different kinds of cleansers, one of which was organic and the other of which was made in the United States.  Half of the people in each group were allowed to choose which cream they wanted to have applied, while the other had a cream selected for them by the experimenter.  Then, they put their hand in the water for over a minute and then rated their discomfort.
The people who had no choice over the cream they got experienced slightly less pain when they were told the cream was a protector than when they were told it was a cleanser.  This finding is a classic placebo effect.  People who had a choice showed a different pattern. When people had a choice and like to have control over their lives, then they showed a large placebo effect.  Choosing a protecting cream led them to feel much less pain than choosing a cleansing cream.  People who do not desire control over their lives showed no difference in their perceived pain regardless of whether they were offered a choice between protecting creams and cleansing creams.
So, the placebo effect was most powerful for those people who desire control and were given a choice.
This finding was repeated in a second experiment involving a choice of colors that some people were told are soothing, where the pain was a loud noise.  In addition, a third experiment found that the desire for control could be manipulated by having people imagine situations in which they did not have control and wanted it or had control when they didn’t want it.  The same pattern was observed in both of these studies.  When people had a high desire for control, then choosing a treatment led to large placebo effects.  When they had a low desire for control, then choosing a treatment removed the placebo effect.
What does all of this mean?
Placebo effects are extremely powerful, particularly for pain relief.  So, it is valuable to know when the largest placebo effects will be observed.
Choice of treatments can be good, but it depends on how much people like to have control.  Those people who (either because of their personality or the situation) like to have control over their lives should be able to choose their treatments.  Those people who do not like to have control over their lives should have their treatments chosen for them. 
Finally, it is important to recognize that this study involved only placebos.  There were no active ingredients in any of the treatments given in this study.  It is not entirely clear what will happen when the treatments also involve actual drugs.