Originally Posted by mravg
That is the rate of sexual dysfunction in the placebo group. That does not mean that placebo caused it, it is just the baseline level!
… But you said that since wellbutrin and placebo had the same effect that means they both negatively impact sexual function and that is just wrong.
I agree that it could have been the baseline, except for one important point: the participants were selected for normal sexual function.
METHOD: Adult outpatients with moderate to severe DSM-IV-defined MDD and normal sexual functioning were randomly assigned
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The purpose of a placebo is to compare to a variable under study to see if that variable has an effect on a certain parameter.
Agreed.
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For example, in one Viagra trial, something like (an astounding) 25% of the placebo group reported an improvement in erections.
That is astounding.
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Now, that has nothing to do with the effectiveness of the sugar pill they took on erectile quality. It had to do with the psychology of taking a pill they thought might help with EQ. It was all psychological.
I agree. However, “all psychological” may minimize the importance of your brain.
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So, if the Viagra group also had a result of 25% of participants reporting a benefit, then the conclusion would be that Viagra doesn’t work, not that they both work!
Gotta disagree here. Clearly if there is a 25% improvement, than both interventions were 25% effective. You may be shocked to know this but there are many drugs that are statistically no better than placebo. Also many drugs are never compared to placebo.
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In other words, you could give a pill made out of any ineffective substance and reach that (25)% effectiveness level. To prove the drug works you need to show a statistically significant difference compared to placebo.
Again, many drugs only need to show a significant difference compared to another drug, not placebo. Frequently, drugs are approved that do not show a statistical difference from other drugs, but have other advantages… such as affording a new patent.
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That is the whole point of putting placebos into a trial in the first place.
You can not prescribe placebo, if you could people would have significant improvement for certain disorders, with minimal side effects. “Minimal”… yes actually placebos do have side effects, despite the fact that they are largely inert.
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You could measure sexual function in a group before taking Wellbutrin, and then again after taking it. Why aren’t studies done this way?
Some are done this way, it is called a crossing study or something.
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The placebo is added to the study because the “other factors” affect both the placebo and drug groups, so differences between those two groups can be attributed to the drug. Same as placebo means the drug doesn’t effect the parameter.
Yes it is added to examine effects of the other factors. And same as placebo does mean that the effect can not be proven to be due to the drug.