Double-blind trails

Cases of allergenic hypersensitivity caused by food additives are rather rare (0.03%-0.23% of population) (Wuthrich 1993) and difficult to diagnose (Spergel and Fiedler 2005). The prevalence rate of food-additive-induced asthma exacerbations obtained by using double-blind, placebo-controlled trails is about 5% (23%-67% of asthmatics believe that food additives exacerbate their asthma) (Bush and Montalbano 2008). One of the reasons why it is difficult to diagnose the exact effect of food additives is the fact that ingredients which appear in food products in very... 

Sushma, S., Dasarathy, S., Tandon, R.K., Jain, S., Gupta,S., Bhist, M.S. Sodium benzoate in the treatment of acute hepatic encephalopathy a double-blind randomized trail Hepatology 1992 16 138—144... 

Cohen, M. Wolfe, R. Mai, T. Lewis, D. A randomized, double-blind, placebo-controlled trail of a topical cream containing glucosamine sulfate, chondroitin sulfate, and camphor for osteoarthritis of the knee. J. Rheumatol. 2003, 30 (3), 523-528. 

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