Department of Public Health and Community Service.
Department of Psychology, Montclair State University.
Psychol Assess. 2018 Feb;30(2):204-219. doi: 10.1037/pas0000470. Epub 2017 Mar 16.
The countdown method is a well-known approach to reducing the average length of screening instruments that are presented by computer. In the countdown method, testing is terminated once the result of the screener ("positive" or "negative") has been unambiguously determined from prior answers. Previous research has examined whether presenting dichotomously scored items in order from "least to most frequently endorsed" or "most to least frequently endorsed" is more efficient when the countdown method is used. The current study describes the Mean Score procedure, an extension of the above item ordering procedures to polytomously scored items, and evaluates its efficiency relative to the distribution of other possible item orderings in 2 real-data simulations. Both simulations involve item responses to the Posttraumatic Stress Disorder (PTSD) Checklist for DSM-5 (PCL-5). In the first simulation, items were scored polytomously, and a single cutoff point was used to determine the screening result. In the second simulation, items were converted to dichotomous scores, as well as categorized into 4 clusters; a positive result for the entire assessment was obtained if and only if a positive result was obtained for each cluster. The latter simulation also investigated the effect of reordering the clusters themselves on the efficiency of the countdown method. Results indicated that the Mean Score procedure does not necessarily produce the optimal ordering, but tends to assemble an efficient item ordering relative to the distribution of possible orderings. In the second simulation, reordering the clusters themselves affected efficiency. Future research directions are suggested. (PsycINFO Database Record
倒数计时法是一种众所周知的方法，用于减少通过计算机呈现的筛选工具的平均长度。在倒数计时法中，一旦根据先前的答案明确确定了筛选器的结果（“阳性”或“阴性”），测试就会终止。先前的研究已经检验了当使用倒数计时法时，按“最不常被认可到最常被认可”或“最常被认可到最不常被认可”的顺序呈现二分评分项目是否更有效。本研究描述了平均分程序，这是对上述项目排序程序的扩展，适用于多分评分项目，并在 2 个真实数据模拟中评估其相对于其他可能的项目排序分布的效率。这两个模拟都涉及到对 PTSD 检查表（PCL-5）的项目反应。在第一个模拟中，项目被多分评分，使用单一的截止点来确定筛选结果。在第二个模拟中，项目被转换为二分评分，并且分为 4 个簇；如果每个簇都获得阳性结果，则整个评估获得阳性结果。后一个模拟还研究了重新排列簇本身对倒数计时法效率的影响。结果表明，平均分程序不一定产生最佳排序，但相对于可能的排序分布，倾向于组合有效的项目排序。在第二个模拟中，重新排列簇本身会影响效率。建议了未来的研究方向。
