| An estimated 7,000 people per year die in the U.S. as a result of medication errors (AHRQ, 2000a). Nearly 30% of patients receiving home healthcare services have potential medication problems (Meredith, Feldman, Frey, et al., 2001). Computer systems have been implemented in healthcare to improve clinical decision-making. The effectiveness of the computer in promoting patient safety is dependent on the usability of the system for clinicians. The purpose of this study was to evaluate the usability of an existing home healthcare computer system used by nurses. The medication order entry task was selected for this study due to the critical need for safety in the performance of the task. Concepts and methods from nursing informatics and Human-Computer Interaction research were used to observe and analyze the task exchange. The nurse-computer interaction was examined to identify: (1) the components of the computer interface used by the nurses, (2) the usability characteristics of the interface components, and (3) the outcomes of the task performed.; The study consisted of two phases. Phase I entailed a task analysis which identified the clinical and operational elements of medication order entry. In Phase II, 14 nurses performed the medication order entry tasks as specified by two task scenarios. Data were collected through the use of audio taped talk-alouds, digital screen tracking software, and observations. The task exchange data were examined for indicators of usability: (a) accuracy, (b) patient safety, and (c) efficiency.; Usability difficulties resulted in an error frequency rate of 59% for entering the medication orders. The computerized patient safety features of Adverse Interaction Checking and Patient Teaching Guides were virtually unused due to the lack of depth and breadth of content of these modules. Repeated searches for the right medication compromised the efficiency of the task by adding and average of 33 extra steps and two extra minutes to enter one medication. |
