社会与工程心理学研究室知识库

    本研究通过实地调研发现了现阶段远程医疗系统的图像呈现系统的界面设计中存在的问题，提出了“电脑屏幕上同时呈现图片的数量和尺寸对医生进行灰度医学图像搜索和诊断任务绩效和信息加工方式的影响”的问题，用模拟任务实验的方法考察了任务难度(图形间的尺寸变化)、电脑屏幕上每屏呈现图片的数量、电脑屏幕上每屏呈现图片的尺寸等因素对人完成类似医学影像诊断的灰度图形搜索和比较任务的绩效和信息加工策略的影响。结果显示:
    (1)不同的任务难度(目标图形和答案图形的尺寸差异)显著影响完成任务的正确率和反应时。即目标图形和答案图形尺寸差异小、比较难度大的任务，任务正确率低，反应时长;目标图形和答案图形尺寸差异大、比较难度小的任务，任务正确率高，反应时短。
    (2)图片呈现界面(每屏呈现图片的数量和每张图片的尺寸)显著影响完成图形搜索和比较任务的绩效和主观满意度。其中图片的数量的作用表现为:每屏呈现图片的数量增加，完成灰度图形搜索和比较任务的反应时减短，使用者满意度增加;每屏呈现图片的数量减少，完成
任务的反应时增长，使用者满意度降低。每屏呈现图片的数量对任务正确率没有显著影响。图片尺寸的作用表现为:呈现图片的尺寸较大，任务难度相对较低;呈现图片的尺寸较小，任务难度相对增大。但是只要尺寸差异的难度在一定的限度之内，图片呈现尺寸的变化对人的任务绩效没有显著影响。
    (3)每屏呈现图片的数量对完成任务时采取的信息加工策略有一定的影响，表现为多图片界面更有利于混合策略进行快速搜索。但这一结论还有待进一步研究的证实。
    (4)被试完成任务的负荷量决定了所使用界面呈现图片的数量和图片尺寸的最佳配比一一当任务负荷量与被试信息加工能力匹配或者有所冗余时，被试的任务绩效达到最佳且任务反应时相对恒定。任务负荷量由任务难度、呈现图片数量、被试采用的信息加工策略等共同决定。

    Based on the field investigation for the user interface design of the telemedicine systems currently used at the local hospitals, a question "How do the number of pictures and the picture size displayed on the software interface affect the doctors' image viewing and diagnosis performance and their information processing behavior on a desktop computer screen?" was raised. To answer it, two laboratory experiments, the experiment task of which was to simulate the doctors' task of image viewing and diagnosis on a PC screen, were conducted to explore how several factors including task difficulty (Size difference between target objects and answer objects), the number of pictures displayed on one screen, picture size, etc. affect people's performance and information processing on grey-scale objects searching and comparing. Results of the study showed that;
    (1) Task difficulty (Size difference between target objects and answer objects) demonstrated significant main effect on users' performance both on accuracy and reaction time. The smaller the size difference between target and answer objects, the higher the task difficulty, people perform slower and make more errors; while the bigger the size difference between target and answer objects, the lower the task difficulty, people perform faster with a higher accuracy rate.
    (2) Image display interface (the number of pictures displayed on one screen and the size of each displayed picture) affect significantly the users' task performance and satisfaction toward the interface.The more pictures displayed on one screen, the shorter the users' reaction time and the higher the users' satisfaction; the fewer pictures displayed on one screen, the longer users' reaction time and the
lower users' satisfaction. The number of pictures displayed on one screen has no significant effect to users' taske accuracy rate. The larger the picture size displayed, the lower task difficulty; while the smaller the pictuer size displayed, the higher the task difficulty. But if the size difference displayed on the screen is beyond human's visual limen on distiguishing objects' size difference, the displayed picture size has no significant effect on users' performance.
    (3) The number of pictures displayed on one screen has some effect on people's strategy of distributing their attentional resources. People seem to prefer random search strategy on the interface with many pictures displayed. But this conclusion still needs more specific research to confirm in future.
    (4) The user's workload while completing tasks on the screen decided the best interface on which the number of pictures displayed and the picture size were optimized for a best perfomace. If the workload is higher than or equal to user's information processing ability, the user make a best use of his or her information processing abilty and the performance is the best while the reaction time is relatively constant. The workload was decided by several factors including task difficulty, the number of pictures displayed, the search strategy and etc.