by unriggable on Mon Jul 30, 2007 11:27 pm
Angelican, the placebo effect is where you think you will be saved when in fact it doesn't help much. Study found on wikipedia:
"In post-World War II 1946, pharmaceutical chemicals were in short supply. One U.S. headache remedy manufacturer sold a drug that was comprised of three ingredients: a, b, and c. Chemical b was in short supply.
Jellinek was asked to test whether or not the headache drug's overall efficacy would be reduced if ingredient b was missing.
Jellinek set up a complex trial involving 199 subjects, all of whom suffered from "frequent headaches". (Originally there were 200 subjects, but one did not complete the trial.) The subjects were randomly divided into four test groups. He prepared four test drugs, involving various permutations of the three drug constituents, with a placebo as a scientific control. The structure of this trial is significant because, in those days, the only time placebos were ever used "was to express the efficacy or non-efficacy of a drug in terms of "how much better" the drug was than the "placebo". (Jellinek (1946), p.88. Note that the trial conducted by Austin Flint is an example of such a drug efficacy vs. placebo efficacy trial.) The four test drugs were identical in shape, size, colour and taste:
* Drug A: contained a, b, and c.
* Drug B: contained a and c.
* Drug C: contained a and b.
* Drug D: a 'simulator', contained "ordinary lactate".
Each time a subject had a headache, they took their group’s designated test drug, and recorded whether their headache had been relieved (or not). Although "some subjects had only three headaches in the course of a two-week period while others had up to ten attacks in the same period", the data showed a "great consistency" across all subjects (Jellinek, 1946, p.88). Every two weeks the groups’ drugs were changed; so that by the end of eight weeks, all groups had tested all the drugs.
The stipulated drug (i.e., A, B, C, or D) was taken as often as necessary over each two-week period, and the two week sequences were:
1. A, B, C, D
2. B, A, D, C
3. C, D, A, B
4. D, C, B, A.
Each group took a test remedy for two weeks. The trial lasted eight weeks, and by the end of the trial all groups had taken each test drug for two weeks (although each group had taken them in a different sequence). Over the entire population of 199 subjects, 120 of the subjects responded to the placebo, and 79 did not; i.e., there were 120 "subjects reacting to placebo" and 79 "subjects not reacting to placebo".[22]
At first glance there was no difference between the self-reported "success rates" of Drugs A, B, and C (84%, 80%, and 80% respectively) (the "success rate" of the simulating placebo Drug D was 52%); and, from this, it appeared that ingredient b was completely unnecessary.
However, in quite a remarkable way, the trial eventually did demonstrate that ingredient b did make a significant contribution to the remedy’s efficacy. Examining his data more closely, Jellinek discovered that there was a very significant difference in responses between the 120 placebo-responders and the 79 non-responders. The 79 non-responders' reports showed that if they were considered as an entirely separate group, there was a significant difference the "success rates" of Drugs A, B, and C: viz., 88%, 67%, and 77%, respectively. And because this significant difference in relief from the test drugs could only be attributed to the presence or absence of ingredient b, he concluded that ingredient b was essential (thus contradicting his initial conclusion, derived from the comparison between the "success rates" for all test subjects, that Drugs A, B, and C were equally efficacious)."
[quote="MR. Nate]What about the fact that Duke University has nearly complete copies from around 250? Which pope edited those?[/quote]
Did they read them? I'm sure they are different from today in many ways. It would be impossible for them to be identical.
