Double blind placebo what?-A A +A
By Andy Uyboco
Thursday, August 29, 2013
MOST people have, at one time or another, encountered a friend or relative selling miracle cures. It may be something conventional like a tablet, juice, ointment or aromatic oil. It may also be something unheard of like a bracelet, a skin patch, magnets, or stickers. The seller will usually have a handful of written testimonials (with photos) or video footages “proving” the effectiveness of the product against cancer, goiter, asthma and a whole host of other diseases.
The question now is, how do you decide whether to believe them or not?
I have a confession to make. I used to be one of those selling such products when I was still based in Manila. I worked with a company which sold health products (pills and drinks). To be fair to the company however, they never marketed their products as cures but as nutritional supplements.
Some distributors, however, got it into their heads that they could sell the products better if they targeted them as cures for certain diseases. One such disease was a skin problem called psoriasis. The strategy worked for a time so we neophytes decided to mimic their style.
So, armed with testimonials and product brochures, I charged into the clinic of a dermatologist who claimed to be specialist of psoriasis. He listened to me for a few minutes, then said, “You know I’ve come across a lot of claims for curing psoriasis, but I will only trust your product if it has been proven in a double-blind, placebo-controlled test and published in a medical journal.”
In my mind I said, "What the hell is that?" But aloud, I only said, "Well sir, I'm sure our company has those. I'll ask for them and bring them back to you."
I asked the more senior people at our office if we had such documents and they said, "Yes, of course we do," but when I pressed and asked for the actual documents, nobody could produce them. So in the end I could only conclude that we didn't have them and I never went back to that doctor again.
But what is so important about a double-blind, placebo-controlled test? Well, I know a lot more about it than I did then so let’s start with what a placebo is -- a placebo is a treatment which has no actual medicinal value, but can seemingly cause a cure.
For example, a man goes to the doctor and complains of a headache. After a thorough examination, the doctor finds nothing wrong, but the patient insists that his head hurts. So the doctor gives the patient a pill, tells him to take it and to call him if the situation improves.
A few hours later, the patient calls and says that the pill worked perfectly and he is feeling quite energetic. He wants to know what that pill was. The doctor then reveals that it was just a sugar pill. The headache perhaps had some psychological cause and the belief that he was taking actual medicine “cured” the patient of it, or the belief caused the mind to release certain chemicals in the body which took care of the disease.
This is called the “placebo effect” and it is a common phenomenon in medicine. Quack doctors and faith healers use this to fool people into thinking they are cured. To protect against this, new drugs or treatments have to pass a double-blind, placebo-controlled test to verify that the drug can actually treat the disease instead of merely relying on the placebo effect.
I'll try to explain how it works in very simple terms. Let’s say, there’s a new drug for asthma called Asmalex. In order to test Asmalex, we find volunteers who have asthma who are willing to undergo the test. These volunteers are split into two groups A (experimental) and B (control). Group A will be given Asmalex and Group B will be given the placebo (sugar pills or cornstarch pills or any other useless pill).
The patients do not know whether they are given real medication or the placebo. That is the first “blind.” The second “blind” is that the ones administering the medicine do not know also whether they are giving the real thing or not -- hence the term “double-blind.”
This method ensures that there are no subconscious signals to make the patient believe whether he is taking the real thing or not, as that belief may affect the results.
After the test period is over, the data is collated and interpreted by a statistician -- and if the researchers want to make the results even more unbiased, they also do not reveal to the statistician which is the control group or the experimental group, thus introducing a third “blind,” and lending more credibility to the conclusion.
If statistics show that the experimental group’s result is significantly better than the placebo group, then the treatment is granted to have a therapeutic effect. The methodology and results are then published in a journal for other researchers to review for errors, or for replication and verification.
So I hope that adds to your knowledge and vocabulary for today, and if someone tries to sell you the latest cure-all, be sure to ask for the double-blind, placebo-controlled test. Oh, and if they do happen to produce one, make sure to read it thoroughly.
Just because they can produce some piece of paper does not necessarily make it legitimate.
Published in the Sun.Star Davao newspaper on August 30, 2013.