Comprehension and retention of safety pictorials

ideas (e.g. the passage of time). Indeed, some concepts may never be adequately communicated via sim ple pictorials. W olff and W ogalter (1993) and M agurno et al . (1994) describe a set of studies in which pharmaceutical pictorials were iteratively evaluated across a series of test and redesign cycles. Even after several iterations, pictorials of some concepts never reached the ANSI criteria of 85% correct com prehension. The dilem ma then becomes what to do when it is not possible (or practical) to design a readily understandable pictorial for a particular concept. One possibility is to train people on the meanings of various pictorials (Green and Pew 1978 , Cairney and Sless 1982). Effective training should not only facilitate understanding in the short term but should also ensure comprehension in the long term. In addition, a practical concern is that the training should be simple and brief to keep costs low in terms of resources, time and money. One training method that ®ts the above criteria is to simply expose individuals to pictorials with their associated written verbal descriptions. W ickens (1992) suggests that communicating via pictorial/text combinations facilitates inform ation proces- sing by prom oting ¯exibility, thereby enabling people to capitalize on the information extraction m ethod (spatial pictures or semantic language) that they process best. W ickens further believes that pictorials provide an overall context or `frame’ within which words can be used to ®ll in critical details of the pictured concept. W iseman et al . (1985) refer to this as processing elaboration. To W isem an et al . (1985) concept memory is enhanced by the combined processing of words and pictures, and m emory quality is im proved as the details of pictures and words synthesize. W hen combining text and pictorials, researchers have suggested that concept memory will be enhanced even further as additional detail is provided by the textual description (Paivio 1975 , D’Agostino et al . 1977). In general, greater textual detail provides ad ditional information that m ay not be readily apparent in either pictured concepts or less-detailed simple text. W hen applied to warnings, the greater detail may supply inform ation an d thus facilitate memory for critical concepts such as hazard severity, explicitness, or consequences. 532 M . S. W ogalter et al.