Trials double blind

Pyridoxine is used in morning sickness. Its mechanism of action remains unclear and several reviews of the use of pyridoxine have failed to find conclusive evidence of effectiveness. A recent double blind trial found pyridoxine to be of benefit in reducing nausea only. Some clinicians use pyridoxine as the first drug on the basis that it is the least likely to be toxic to the foetus. 

Haddad AL, Matos LF, Brunstein F, et al (2003) A clinical, prospective, randomized, double-blind trial comparing skin whitening complex with hydroqui-none vs. placebo in the treatment of melasma. Int J Dermatol 42 153-156... 

The first proper double blind trial of embryonic implants in 40 PD patients (20 undergoing just surgery without any implant), has shown no improvement in patients over 60 years but some clinical benefit (fewer symptoms between levodopa dosing) in those below that age. Unfortunately some of these responders eventually developed dyskinesias, a sign of too much dopamine, and further implants were halted until the technique has been re-evaluated, see Freed, CR et al. N EnglJ Med 2001, 344 710-719. 

The aim of our project was to study phloem as a source of fiber and polyphenols, and to develop a method to improve its taste without losing the potentially bioactive polyphenols. In addition, we wanted to investigate the bioavailability, cholesterolemic and antioxidative effects and safety of phloem and its phytonutrients in humans in a randomised double-blind trial. 

Buerger s disease plus arteriosclerosis obliterans (double blind trial) ... 

Why are side effects important Imagine that you have been recruited for a clinical trial of an antidepressant medication. As part of the required informed-consent procedure, you are told that you may be given a placebo instead of the active medication, but because this is a double-blind trial, you will not be told which you are getting until the study is over. You are told that... 

Grabowski J., Rhoades H., Silverman P et al. Risperidone for the treatment of cocaine dependence randomized, double-blind trial. J. Clin. Psychopharmacol. 20 305, 2000. 

Maurer M, Henn V, Dittrich A and Hofmann A (1990). Delta-9-THC shows antispastic and analgesic effects in a single-case double-blind trial. European Archives of Psychiatry and Clinical Neuroscience, 240, 1-4. 

R, Runzi M, Kron M, Kahl S, Kraus D, Jung N, Maier L, Malfertheiner P, Goebell H, Beger HG German Antibiotics in Severe Acute Pancreatitis Study Group Prophylactic antibiotic treatment in patients with predicted severe acute pancreatitis A placebo-con-trolled, double-blind trial. Gastroenterology 2004 126 997-1004. 

Alvisi A, D Ambrosi A, Onofri W, Catellani M, Palazzini E Treatment of secretory diarrhoeas. A double-blind trial of the effectiveness of rifaximin (L 105) and neomycin. Clin Trials J 1984 21 215-223. 

Solotof JI, Gudmand Hoyer E, Kreg B, Kris-tensen E, Wolff HR A double blind trial of wheat bran on symptoms of irritable bowel syndrome. Lancet 1976 i 270-272. 

Pharmacokinetic studies in patients yielded an estimated product half-life of approximately 20 days (11-50 days range) and the product clearance was found to be variable according to body weight, gender and tumour burden. Safety and efficacy were established by three randomized, controlled trials. The first study was a randomized double-blind trial involving 813 patients. The primary end-point measured was overall survival, which was extended from a median of 15.6 months to 20.3 months. 

Herrman, W. M., Horowski, R., Dannehl, K., Kramer, U., and Lurati, K. (1977) Clinical effectiveness of lisuride hydrogen maleate A double-blind trial versus methysergide. Headache, 17 54-60. 

Another practice is to blind the trial, which means that the subjects are not privy to whether they receive the placebo or drug. In some trials, even the investigator is unaware of whether the subject is in the control or active group. This is called a double-blind trial. The rationale is to ehminate the possibihty of bias affecting the trial results. 

Official Title Effect of EGb 761 on the Ratio of the Isoforms of the Protein Precursor of Beta Amyloid Platelets on Patients With Mild to Moderate Alzheimer s Disease. A Phase II, Randomized, Double-Blind Trial, on Parallel Groups Versus Placebo Primary Outcome Measures Effect of EGb 761 on the ratio of the isoform of the protein precursor of beta amyloid platelets Secondary Outcome Measures Efficacy of EGb 761 on the cognitive functions and safety of EGb 761 at a dosage of 240 mg per day Total Enrollment 40 Study Start July 2005... 

Marshall, B. J., Goodwin, C. S., Warren, J. R., et al. (1988) Prospective double-blind trial of duodenal ulcer relapse after eradication of Campylobacter pylori. Lancet. 2, 1437-1442. 

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