Formative evaluation in document design: validity of the plus-minus method for the pretesting of public information brochures.

The article provides empirical data on the validity of the plus-minus method for the pretesting of public information brochures. Six brochures were tested using the plus-minus method, and revised on the basis of the pretest results. A series of experiments comparing original and revised versions of the brochures showed that the reader problems detected were valuable ones: both the target readers appreciation of the brochures and the effectiveness of the brochures themselves showed a significant improvement. Another study in which experts judged the importance of the problems detected confirmed these findings, but also raised doubts about the extent to which individual revisers can reliably judge the importance of reader problems