其他摘要：Background The aim of using distracters in multiple-choice questions (MCQs) is to distract those who don't know the correct answer of the question. The MCQs must be designed in a way that the students who have reached the pre-determined educational objectives, have a better chance in finding the correc1 answer than those who have not. Therefore, a question has an appropriate efficacy when more /ow-grade students are attracted to the distracters than high-grade students. Purpose Considering the important role of distracters in differentiating between low and high-grade students, this research studies the distracters in the multiple-choice tests (MCTs) given in Mashad Medical School in the first semester of 1001-2002. Method In this descriptive study, the data of 21 MCTs performed in one semester were collected and recorded by Optical Mark Reader (OMR). From 128-1 questions, 6-12 MCQ ques1io11s were sampled randomly, and the numbers of low and high-grade students choosing the distracters were compared and analyzed using SPSS software. Results The efficacy of 45.9% of distracters was ''relatively weak" to "extremely weak", with "relatively weak", "weak", "very weak" and "extremely weak" distractors having a prevalence of 11.4%, 10%, 15.1% and 9.4% respectively. Extremely weak distracters were those that had a negative impact. Which means the high-grade students were more attracted than the low-grades. Of the MCQs. -12.7% had one. and one third of the questions had two weak distracters. Among all 6- questions. only 15.1% had three good distracters. Conclusion Our study showed that more than half of he distracters had a weak quality. So we suggested that before performing a test, the experts ' opinion about the designed questions should be obtained and considered to minimize the technical problems of the questions.
关键词：multiple-choice test; distracter. Test analysis
