ArticleBobon DP.
Acta Psychiatr Belg. 1978 Jul-Aug;78(4):635-45.
Before the development of audiovisual techniques, it was impossible to avoid two time-related biases in drug evaluation: rating on different occasions, i.e. in different mood states as regards the rater (the so-called time-gap); knowledge by the rater of the sequence of his ratings. In order to make a time-blind evaluation possible, the author has worked out the following steps: tape-recording of the interviews, standardization of the interview, elimination of questions endangering a time-blind analysis, evaluation of the different interviews of the same patient on different rating sessions. The author summarizes his first three drug trials analyzed according to the time-blind procedure, and concludes that this procedure is a definite progress regarding the validity of drug research.