The Effects of Context on the Comprehension of Graphic Symbols

Abstract

When graphic symbols are used to convey warning information, these symbols must be evaluated for effectiveness prior to their use. In general, the ability of these symbols to convey their intended meaning has been determined in tests which provide no contextual information surrounding the symbols. In the present study, 75 university students were tested to determine their comprehension of twenty different symbols using various context conditions. Verbal context was provided in two forms: full context and partial context. Full context consisted of a two- sentence description of the setting in which the symbol would be presented. Partial context consisted of a more general, two-word description of the use context. The control condition presented the symbols without contextual information. Comprehension was higher when full context was provided with the symbols than when the symbols were presented in isolation. For some symbols, the full context condition resulted in higher comprehension than the partial context condition and the partial context condition resulted in higher comprehension than the no context condition. Comprehension accuracy was also affected by the subject's familiarity with the symbols. Comprehension was higher for symbols rated high in familiarity than for symbols rated lower in familiarity. On the basis of these findings, a recommendation was made that evaluations should provide some form of contextual information along with the symbols to allow a more realistic test of symbol comprehension.