School of Health Information Sciences, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
Int J Med Inform. 2010 Jul;79(7):501-6. doi: 10.1016/j.ijmedinf.2010.04.001. Epub 2010 May 7.
Many Electronic Health Record (EHR) systems fail to provide user-friendly interfaces due to the lack of systematic consideration of human-centered computing issues. Such interfaces can be improved to provide easy to use, easy to learn, and error-resistant EHR systems to the users.
To evaluate the usability of an EHR system and suggest areas of improvement in the user interface.
The user interface of the AHLTA (Armed Forces Health Longitudinal Technology Application) was analyzed using the Cognitive Task Analysis (CTA) method called GOMS (Goals, Operators, Methods, and Selection rules) and an associated technique called KLM (Keystroke Level Model). The GOMS method was used to evaluate the AHLTA user interface by classifying each step of a given task into Mental (Internal) or Physical (External) operators. This analysis was performed by two analysts independently and the inter-rater reliability was computed to verify the reliability of the GOMS method. Further evaluation was performed using KLM to estimate the execution time required to perform the given task through application of its standard set of operators.
The results are based on the analysis of 14 prototypical tasks performed by AHLTA users. The results show that on average a user needs to go through 106 steps to complete a task. To perform all 14 tasks, they would spend about 22 min (independent of system response time) for data entry, of which 11 min are spent on more effortful mental operators. The inter-rater reliability analysis performed for all 14 tasks was 0.8 (kappa), indicating good reliability of the method.
This paper empirically reveals and identifies the following finding related to the performance of AHLTA: (1) large number of average total steps to complete common tasks, (2) high average execution time and (3) large percentage of mental operators. The user interface can be improved by reducing (a) the total number of steps and (b) the percentage of mental effort, required for the tasks.
许多电子健康记录（EHR）系统由于缺乏对以人为中心的计算问题的系统考虑，无法提供用户友好的界面。可以改进这些界面，为用户提供易于使用、易于学习且不易出错的 EHR 系统。
评估 EHR 系统的可用性，并提出用户界面的改进领域。
使用认知任务分析（CTA）方法（称为 GOMS[目标、操作、方法和选择规则]）和相关技术（称为 KLM[击键级别模型]）分析 AHLTA（武装部队健康纵向技术应用程序）的用户界面。使用 GOMS 方法通过将给定任务的每一步分类为心理（内部）或物理（外部）操作来评估 AHLTA 用户界面。这项分析由两名分析师独立进行，并计算了组内相关系数以验证 GOMS 方法的可靠性。进一步的评估使用 KLM 通过应用其标准操作集来估计执行给定任务所需的执行时间。
结果基于对 14 个由 AHLTA 用户执行的原型任务的分析。结果表明，平均而言，用户需要经过 106 步才能完成一项任务。要执行所有 14 项任务，他们将花费大约 22 分钟（与系统响应时间无关）用于数据输入，其中 11 分钟用于更费力的心理操作。对所有 14 项任务进行的组内相关系数分析为 0.8（kappa），表明该方法具有良好的可靠性。
本文通过实证揭示并确定了与 AHLTA 性能相关的以下发现：（1）完成常见任务的平均总步骤数较多，（2）平均执行时间较高，（3）心理操作比例较大。可以通过减少（a）完成任务所需的总步骤数和（b）心理工作量来改进用户界面。
