Effects of a computer-based calculation aid and visual cues on task performance of medication dose calculation being interrupted

Abstract

Interrupting medication dose calculation represents a significant threat to patient safety, as it is likely to increase risk of calculation errors and time to do the task. A computer-based, step-by-step calculation aid and visual cues can be promising tools for mitigating negative impacts of interruptions; however, their effectiveness should be fully investigated. Two experiments were conducted in this present study. Experiment 1 (N=60) examined whether the use of a computer-based, step-by-step calculation aid in situations where there were and were no interruptions would help reduce errors (defined as the medication dose being calculated incorrectly) and task completion time (defined as the amount of time spent on medication dose calculation). Experiment 1 was based on a 2 × 2 mixed factorial design, with calculation aid as a between-subject factor (levels: with-calculation aid and without-calculation aid) and interruption as a within-subject factor (levels: presence of interruptions and absence of interruptions). The primary dependent variables of Experiment 1 were error rate and task completion time. Experiment 2 (N = 54) examined whether the use of visual cues in situations with interruptions could improve task performance and assist task resumption. Experiment 2 was based on a within-subject repeated measures design, with visual cues as a within-subject independent variable (levels: no-cue, spatial-cue, and content-cue). The primary dependent variables of experiment 2 were error rate and task completion time, and the secondary dependent variables were resumption error rate and resumption lag. This study examined a medication dose calculation task that required the determination of the administration rate (in µg/kg/min) of intravenous (IV) medications for a pediatric patient using a computer. The administration rate could be calculated using a computing mechanism that involved mathematical computations and unit conversions. Despite that no statistically significant decrease in error rates were observed in both experiments, the results of Experiment 1 showed that the use of the computer-based, step-by-step calculation aid significantly reduced task completion time in situations where there were and were no interruptions. The results of Experiment 2 showed that visual cues significantly reduced resumption error rates and resumption lag when compared with the situation where there was no-cue. The computer-based, step-by-step calculation aid and visual cues have the potential to mitigate the time cost induced by interruptions. However, their effects on error rate need further investigation. The calculation aid can be implemented in a computer-based order entry system as means of independent checking of medication dose, and its effects in improving medication safety should be further investigated in clinical settings.