At least six controlled studies show that cognitive behavior therapy can improve symptoms and lessen disability somewhat.
Also, he says, no randomly controlled studies have shown that either aspirin or other anti-inflammatory drugs reduce colon cancer deaths.
In fact, it was one of the placebo-controlled studies, begun in 1999, that resulted in Vioxx being pulled from the market.
The mean TTR for warfarin in ROCKET was 55%, compared to 63%-73% in other recent warfarin-controlled studies, according to the reviewers.
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These are the kinds of big, randomized, controlled studies that the U.S. Food and Drug Administration requires before a new drug is approved.
In recent years, two larger placebo-controlled studies have been published.
Many people enthusiastically tried the so-called Feingold Diet, but the enthusiasm waned as the years went on and "some very well-done randomized controlled studies" questioned Feingold's theory, says Deborah Pearson, Ph.
In one of the best-controlled studies, CpsC researchers in 1978 found that an expensive program that included handing out safety brochures to individual consumers had no effect on lawn mower injuries.
That research, however, typically didn't involve randomized, controlled studies.
Robert Langreth, who wrote the article on longevity (see p. 112), has a scientific frame of mind, which means that he puts faith in controlled studies and molecular biology and gives little credence to anecdotal evidence.
Genentech, in contrast, has insisted on large, controlled clinical studies that prove its drugs work beyond a reasonable doubt.
An analysis of neurological and psychiatric effects in placebo-controlled Chantix studies of 5, 000 patients will be presented at a medical meeting in Rome later this month.
In 2002 two controlled human studies stunned intensive care specialists by finding that cooling the body temperature 7 degrees helped prevent brain damage in patients whose hearts had stopped and been restarted after cardiac arrest.
University of Pittsburgh researchers conducted what certainly must rank as one of the largest scientifically controlled happy hour studies, enlisting 720 subjects for the project.
Medical research commonly employs three kinds of study designs: observational studies, randomized controlled trials (RCTs), and metaanalyses.
Animal studies showed that squalamine controlled infections of yellow fever, Eastern equine encephalitis virus, and murine cytomegalovirus.
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Claire Bombardier, the University of Toronto researcher who had conducted Merck's big ulcer study, criticized the new studies for not being placebo-controlled.
Twenty-one of the studies included in the review were randomized controlled trials, which are considered the gold standard for scientific research.
Results of methodologically rigorous studies are consistent with those obtained from randomised controlled trials, but sensitivity is particularly dependent on appropriately detailed recording and analysis of aspirin use.
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But randomized controlled clinical trials also are used to prove benefit in big drug studies.
Studies that were often double-blind and placebo-controlled.
Estrogen hormone replacement therapy seemed to have all sorts of benefits based on observational studies, but they vanished under the more rigorous lens of controlled clinical trials.
All of the studies ran for at least a year, and all were randomized controlled trials, the most rigorous type of study.
The FDA approval comes without a controlled clinical trial, which is usually required for a regulatory OK. But in studies, Velcade clearly helped a third of multiple myeloma patients who had failed two or more previous therapies--a stunning result in such a lethal disease.
Paxil CR and Paxil have not been directly compared with one another, but in studies comparing each to placebo, patients were less likely to stop taking the controlled-release version because of side effects.
In the accepted hierarchy of evidence generation, the results of a randomized, controlled clinical trial usually take precedence over other forms of evidence such as meta-analysis and observational studies.
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