University of Louisiana at Monroe College of Pharmacy, Monroe, LA, USA.
Am J Pharm Educ. 2013 May 13;77(4):71. doi: 10.5688/ajpe77471.
To determine the effect of 3 variations in test item format on item statistics and student performance.
Fifteen pairs of directly comparable test questions were written to adhere to (standard scale) or deviate from (nonstandard scale) 3 specific item-writing guidelines. Differences in item difficulty and discrimination were measured between the 2 scales as a whole and for each guideline individually. Student performance was also compared between the 2 scales.
The nonstandard scale was 12.7 points more difficult than the standard scale (p=0.03). The guideline to avoid "none of the above" was the only 1 of the 3 guidelines to demonstrate significance. Students scored 53.6% and 41.3% (p<0.001) of total points on the standard and nonstandard scales, respectively.
Nonstandard test items were more difficult for students to answer correctly than the standard test items, provided no enhanced ability to discriminate between higher- and lower-performing students, and resulted in poorer student performance. Item-writing guidelines should be considered during test construction.
确定测试项目格式的 3 种变化对项目统计数据和学生表现的影响。
编写了 15 对直接可比的测试问题，以符合（标准量表）或偏离（非标准量表）3 项具体的项目编写准则。在整体和每项准则中，分别测量了 2 个量表之间的项目难度和区分度的差异。还比较了 2 个量表之间的学生表现。
非标准量表比标准量表难 12.7 分（p=0.03）。避免“以上皆非”的准则是 3 个准则中唯一表现出显著差异的准则。学生在标准和非标准量表上的总分数分别为 53.6%和 41.3%（p<0.001）。
与标准测试项目相比，非标准测试项目更难让学生正确回答，而且无法增强区分高、低表现学生的能力，导致学生表现较差。在进行测试构建时应考虑项目编写准则。
