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An error in "Blind and Double-Blind Techniques" (LETTERS 209:1908, 1969) showed the incorrect date of 1957 in the text, for the citation of Hampson et al. It is shown correctly in the list of references as 1954.
CORRECTION. JAMA. 1969;210(7):1284. doi:10.1001/jama.1969.03160330084030