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Does anyone know who carried out the first true double blind trial and thus invented the methodology?
Noel jackson. LIFE.Newcastle
Is there no controversy or questioning of the validity of blinded studies? What about human subjects being able to guess if they were in the active drug group, and that affecting the results? This is a big enough issue that the statistics of some studies are recalculated or seriously questioned... There must be some criticisms of blinded studies..? --159.178.248.49 (talk) 13:18, 15 March 2010 (UTC)Reply
I agree. I intend to make a project of this issue and how it relates to the Active placebo effect, as even a small error in blinding can trigger a statistically significant result in a large enough study. This topic needs more attention. Wikiman2718 (talk) 08:25, 19 April 2019 (UTC)Reply
For the risk of being laughed at. Is there any proof that mice experiments are not influenced by placebo effect. I can imagine the lab staff talking to the doomed mice "here you buggers, eat this, you will all die soon anyhow." and to the lucky mice "look over to you neighbors, they're gonna die soon, you are the lucky ones". And maybe the mice understand ? If not word for word, but maybe body language.
Is double blind method being used with mice experiments ?
-- Paparodo, dec 13th 2006 —The preceding unsigned comment was added by 217.10.60.85 (talk) 11:46, 13 December 2006 (UTC).Reply
Does anyone know if there was a double-blind study where BOTH groups were given a placebo, but both were told that one group was getting a med and one was not? Did anyone measure what is the % of success of placebo group that is always reported by a placebo group in a double-blind study.
What I am looking for is a percent of success reported from the placebo group?
Was there such study?
Can someone post that?
Thanks.
Atessitore05 13:50, 13 December 2006 (UTC)Reply
If BOTH groups were given placebo, the result should be 1:1 for both groups with an error within a statistical expectation...
The placebo group is group with no real treatment applied - so the possible success of this "treatment" is caused by placebo effect - either people do feel like the "treatment" helps them even if it does not help (important only if results are interpreted based on subjective reports - usual in psychology) or the believe that the treatment should help them really does help them (assuming psychological setup can really affect course of the studied disease). It is also possible the placebo effect does not apply and there is standard course on the placebo group...
Measuring of the placebo effect itself is not important in studies testing drugs etc.
The importancy of the blinded placebo group in a study is that placebo effect applies to both groups - to the so called placebo group and to the really treated group.
Getting results, you can "decrease" possible placebo effect (does not matter how big it really is) from both groups getting "0" on placebo group and real added effect of the treatment on the really treated group. Sometimes you get "0" within statistical tolerance on both (means the studied treatment has no added effect).
So if you create two placebo groups and will give them purple starch pills to help them from migraine, you will get results like: it helped 20% of the group for both...
Then, if you give one of the group real purple ibuprofenum pill, you will get 20% on placebo group and 65% on ibuprofenum group giving you information ibuprofenum helps to at least 45% of the group (simply said ;)
Comparing two placebo groups, however, makes sense for balancing small groups, where inadmissibly high statisticall error is too probable.
E.g. if you have group of 12 people as a statistical set and you divide it into two groups with 6 people, a placebo-placebo test could easily return something like 15% vs. 25% of positive results, though we definitely do expect equal results. This gives an important information about unbalances sets. In such case you can either exchange people in sets and try again or you have to count with higher statistical error. You could get 60% of positive results if the first group got the real treatment and 70% of positive results if the second group got it.
However, real researches work with serious statistical analysis and with big enough statistical sets, and with calculated expected errors producing reliability intervals etc...
Also in real huge researches there is no time and money allocated for testing groups in placebo-placebo mode first. It is understandable if we know we can expect 1:1 result.
--213.160.184.124 (talk) 10:10, 16 June 2009 (UTC)Reply
I'd like clarification on the definition of a double blind study. What if there is an ignorant experimenter, but no subject at all? For instance, suppose we give three weapons to a ballistics expert and ask him which one fired a given bullet? Would that be a double blind test, even though there is only one person (the experimenter) unaware of the correct answer? —The preceding unsigned comment was added by 68.6.94.12 (talk) 16:33, 31 March 2007 (UTC).Reply
Is anyone against merging it here? For that matter, why not just have an article on blinding in general that covers all forms? Richard001 05:31, 24 April 2007 (UTC)Reply
when an experimenter tells the subject that something is X but then switches X with Y in order to observe the existence of the subject's bias? does it have a name? --AnY FOUR! 04:46, 4 August 2007 (UTC)Reply
I'm an ex-subjective audio reviewer (Stereophile) who's had terrible arguments with Arny Krueger, et al, about problems with controlled testing -- namely, that listening under controlled conditions is not the same as listening casually (which is how we actually listen to music). This point -- that controlling the test conditions can also alter them -- needs discussion. WilliamSommerwerck (talk) 14:57, 15 February 2008 (UTC)Reply
Blinding is far from ubiquitous in the scientific method. It is relatively rare in chemistry, physics, geology, meteorology, astronomy, and forensic science. It is even relatively rare in many areas of biology and medicine. I recently reviewed a number of grant proposals related to traumatic brain injury; less than 10% included blinding in their proposed methods. Michael Courtney (talk) 11:45, 1 April 2008 (UTC)Reply
I think the reference:
"Male circumcision 'cuts' HIV risk" ... Retrieved on 2009-05-18.
is not related to blind experiment at all.
1. All the males knew about their circumcision and were equally informed about safe sexual behavior...
2. The experiment was a social behavior study with no intervention from the researcher's side concerning participants' conditions.
I agree male social behavior can be seen as a kind of blind activity if not under a supervision in general ;), but hey, in blind experiment we have to actively make a difference and at the same time we do hide the difference to participants or even researchers to avoid bias...
Even if researchers performed circumcision on half of the group it would not have been a blind experiment.
(btw. I do not think the experiment is correct concerning possible corellation between circumcision and safe sexual behavior - it is pretty logical to assume that people comming from society where it is usual to perform circumcision - i.e. society taking care about "these issues" - will take more care... If a father sends his boy to a tribal medicine man for circumcision, he will more probably also teach him how to avoid HIV)
I would rather remove all the note concerning ethical troubles. The note is valid for experiments in general - once we know the result and it can safely help we should use it for wide public if possible. Does not matter whether it is a blind experiment or not...
--213.160.184.124 (talk) 11:44, 16 June 2009 (UTC)Reply
The lead of the article mention triple-blind experiments and says that more will be discussed later in the article, but triple-blind experiments are never mentioned again in the article. Can somebody add information about what a triple-blind experiment is? --Bando26 (talk) 06:20, 30 August 2009 (UTC)Reply
I believe this is "double blind," and not "double-blind." The latter refers to the adjectival form only, as, by WordNet, "a test procedure in which the identity of those receiving the intervention is concealed from both the administrators and the subjects until after the test is completed; designed to reduce or eliminate bias in the results." —Preceding unsigned comment added by Twipley (talk • contribs) 23:59, 3 November 2009 (UTC)Reply
Recently I have seen sites question the claims of pharma companies that their nicotine replacements products(patches, gums, etc) double the chance of quitting. These claims are all based on double blind studies, but critics argue that the control group of these studies were inproperly blinded.
The problem is that a smoker is intimately familiar with the effects on nicotine and will know if they have been administered a dose or a placebo. In some tests undisclosed amounts of nicotine has been added to the placebos, which could have an adverse effect on quitting. Here is a study that calls for researchers to follow up on how the test subjects perceived the treatment. 141.16.91.106 (talk) 16:23, 29 April 2011 (UTC)Reply
This same technique is used in elections and IT (crypto particularly), perhaps the uses section could be expanded to include those.
I'd suggest that blind experiments are one application of a more general technique. — Preceding unsigned comment added by 77.86.117.208 (talk) 09:50, 8 August 2018 (UTC)Reply