Comprehending product warning information: age-related effects and the roles of memory, inferencing, and knowledge

Two experiments were conducted to determine if age affects comprehension for explicit and implied warning information and, if so, to reveal the nature of such effects. Experiment 1 measured younger (18-23 years) and older (65-75 years) adults' comprehension for real-world warnings via a verification test presented immediately after reading the warnings or after a delay. In Experiment 2, younger (18-22 years) and older (64-76 years) participants also read fabricated warnings that were inconsistent with real-world knowledge. In both experiments, older adults frequently failed to infer the correct hazard and safety information. The older adults also had trouble understanding warning information even when it was explicitly stated (when no inferences were required), especially when memory demands were high and product-specific knowledge could not be used. That many of the older adults did not understand commonly used product warnings indicates that the wording on many household products is not conducive to being understood by everyone who uses them. Actual or potential applications of this research include the recommendation that designers of product labels, warnings, and instructions should consider minimizing memory load and maximizing opportunities for knowledge application when designing consumer warnings.