Residents' subjective mental workload during computerized prescription entry

To examine residents' subjective mental workload when they enter prescriptions in a computerized physician order entry (CPOE) system. Twenty-two residents completed six prescribing tasks in which two factors were manipulated: numerical input method and level of urgency. Data on demographic characteristics, familiarity with CPOE, and pretest performance were collected. The subjective mental workload was measured by the National Aeronautics and Space Administration-Task Load Index (NASA-TLX). Temporal demand (Mean = 34.48) contributed most to residents' workload on the CPOE task, followed by Performance (Mean = 29.23). No significant associations were found between workload and demographic characteristics, CPOE familiarity, or pretest CPOE performance (p's > .05). A 3 x 2 repeated-measures ANOVA yielded main effects of numerical input method [F (2, 19) = 88.358, p < .001, eta(2) = .900] and level of urgency [F (1, 21) = 169.654, p < .001, eta(2) = .890], and interaction of input method and urgency [F (2, 20) = 87.427, p < .001, eta(2) = .900]. Residents' major sources of workload during the CPOE prescription were temporal demand and performance. Prescriptions entered by the row of numbers exhibited the highest workload. Workload increased with higher level of urgency. It is necessary to emphasize the negative impact of subjective workload, especially in prescription task under urgent situation. Further researches focus on medical staff's workload are encouraged to ensure patient safety.