double(-)blind, a.
Applied to a test or experiment conducted by one person on another in which information about the test that may lead to bias in the results is concealed from both the tester and the subject until after the test is made; orig. used of tests for determining the efficacy of drugs.
Quots. 1937, 1948 both refer to a double-blind test.
| [1937 Jrnl. Amer. Med. Assoc. 26 June 2178/2 The data consisted of the patients' judgments regarding changes in pain. These data were secured in a manner relatively free of bias by the use of the ‘blind test’. 1948 Amer. Heart Jrnl. XXXVI. 529 The study was conducted by the ‘blind’ method. The materials for injection..were unknown to the observer as well as to the subject.] 1950 Amer. Jrnl. Med. IX. 146/1 The ‘internal-evaluation’ was made by skilled questioning under conditions of the ‘double blind test’ in which neither the physician nor the patient knew at the time whether the evaluation related to the placebo or khellin. 1954 Proc. R. Soc. Med. XLVII. 197 The only safe way to obtain unbiased opinions from either of them [sc. doctor or patient] is to make them express their opinions without knowing whether the patient received an active drug or not. This is known in America as a double blind test. 1961 Lancet 19 Aug. 423/1 Statistics and certain concepts, such as double-blind trials, are on everyone's mind to-day. 1968 [see extra-sensory a.]. 1970 Sci. Amer. Mar. 62/3 To demonstrate that no cheating was involved, the experiment was repeated on a double-blind basis: neither the investigator nor the subject knew what the dot pattern contained in advance. 1971 Nature 12 Mar. 113/2 It should be noted that this study was not double blind and hence is subject to observer bias. |
b. ellipt. or as n.
| 1960 J. R. Wilson Double Blind i. 12 In an ordinary blind trial the patient does not know which substance he is receiving... There may be reasons why this information is better withheld even from the doctor himself. This is known as a double blind. 1960 N.Y. Times 14 Aug. 77/3 After the first few cases of improvement with griseofulvin therapy were noted, a research method known as the ‘double blind’ was used. 1961 Spectator 3 Feb. 165/1 The well designed trial avoids this unconscious conspiracy by a system known as the double-blind. |