| The impact of perceived workload on performance was examined in this study using a simulated quality control task designed to mimic prescription checking in a pharmacy. Seventy-eight participants checked 80 fictional orders to determine if the correct item, amount and label information was present. Participants were separated into a low (26 to 30%) and a high (34 to 38%) signal probability group to determine if task characteristics moderate the workload-performance relationship. Performance was defined using a sensitivity index (percentage of correctly detected errors) and a specificity index (percentage of correctly-judged non-errors). Also, perceptions of effort, frustration and mental demand were measured twice (mid-task and post-task). Results indicated that only perceptions of effort were reliably related to performance, but only in the initial stages of the task and primarily in the low probability condition. Also, workload tended to increase as the task progressed for both experimental groups, contrary to expectations. |
