Q-Ray? Is the Q for quack?

You probably have seen the infomercials promoting the Q-Ray ionized bracelets on cable TV. They claimed that their bracelets can relieve pain by balancing Ying and Yang. The concept of Ying and Yang is usually synonymous with the interaction of negative and positive ions resulting in a flow of energy that must not be impeded if one wishes to remain in good health.

However, a November 2002 study by Mayo Clinic of Jacksonville concluded that ionized bracelets were no better than duplicate non-ionized bracelets when it came to pain relief. The study was double-blind, randomized and placebo controlled which is standard practice for any medical trial that expects to be taken seriously by reputable scientists.

When one compares the infomercials to the medical study, one is perplexed how so many people could swear by the ionized bracelets when a medical study finds no justification for this conclusion. What does this say about the trustworthiness of testimonial evidence in evaluating medical claims? I believe that we can learn much from the controversy over ionized bracelets when we try to separate wheat of scientific facts from the chaff of myth and pseudoscience.

Is testimonial evidence reliable? No, for many reasons. First, testimonial evidence is tainted by selective thinking. Selective thinking is defined by the Skeptic Dictionary as the process whereby one selects out favorable evidence for remembrance and focus, while ignoring unfavorable evidence for a belief. For example, I might be thinking of someone when that person calls me. I may believe that I just had a psychic experience. However, it is likely that I have forgotten all the times that I was thinking of someone and the phone did not ring. People often associate two events with each other, i.e. wearing ionized bracelets and pain relief, which may or may not be related to each other.

Also, testimonials may be unreliable due to the placebo effect. The placebo effect is described by Scientific American Frontiers as "When people expect to feel better, they often do." The true nature (psychological versus physiological) of the placebo effect may be in dispute, but the placebo effect is real. That is why placebos were included in the Mayo Clinic study. If the study participants do not know whether they are wearing an ionized bracelet or a non-ionized bracelet that looks like the real bracelet(placebo), the placebo effect can be ruled out in explaining any pain relief.

Finally, testimonials may be unreliable due to communal reinforcement. In other words, if everyone else believes that this is good thing, who am I to suggest otherwise. The fact is that your beliefs very rarely emerge in isolation. Your beliefs are often reinforced or discouraged by other people in your social group. Therefore, your otherwise weak testimonial will gain strength as it is reinforced by other people in your social group who are true believers. Of course, if the other people will profit by your belief, they are true believers indeed!

The bottom line is that testimonial evidence is subjective and prone to error. It can be easily manipulated by others who have agendas of their own. I believe that the proper usage of testimonials and anecdotal evidence is to suggest the need for experimental validation of the claim, but it should not substitute for objective scientific evidence.