a way of deciding which product out of a number of competing products is the best or most popular, or how a new product compares with others. People are asked to try the different products and to say which ones they prefer, but they are not told the names of the products.
آزمایش کور, تست با روش کور, آزمون چشمبسته, تست کور, آزمایش مخفی, تست ناشناس