1.Relationship between item difficulty and discrimination indices in true/false-type multiple choice questions of a para-clinical multidisciplinary paper.
Si-Mui SIM ; Raja Isaiah RASIAH
Annals of the Academy of Medicine, Singapore 2006;35(2):67-71
INTRODUCTIONThis paper reports the relationship between the difficulty level and the discrimination power of true/false-type multiple-choice questions (MCQs) in a multidisciplinary paper for the para-clinical year of an undergraduate medical programme.
MATERIALS AND METHODSMCQ items in papers taken from Year II Parts A, B and C examinations for Sessions 2001/02, and Part B examinations for 2002/03 and 2003/04, were analysed to obtain their difficulty indices and discrimination indices. Each paper consisted of 250 true/false items (50 questions of 5 items each) on topics drawn from different disciplines. The questions were first constructed and vetted by the individual departments before being submitted to a central committee, where the final selection of the MCQs was made, based purely on the academic judgement of the committee.
RESULTSThere was a wide distribution of item difficulty indices in all the MCQ papers analysed. Furthermore, the relationship between the difficulty index (P) and discrimination index (D) of the MCQ items in a paper was not linear, but more dome-shaped. Maximal discrimination (D = 51% to 71%) occurred with moderately easy/difficult items (P = 40% to 74%). On average, about 38% of the MCQ items in each paper were "very easy" (P > or =75%), while about 9% were "very difficult" (P <25%). About two-thirds of these very easy/difficult items had "very poor" or even negative discrimination (D < or =20%).
CONCLUSIONSMCQ items that demonstrate good discriminating potential tend to be moderately difficult items, and the moderately-to-very difficult items are more likely to show negative discrimination. There is a need to evaluate the effectiveness of our MCQ items.
Adult ; Choice Behavior ; Education, Medical, Undergraduate ; Educational Measurement ; methods ; Humans
2.A simple instrument for the assessment of student performance in problem-based learning tutorials.
Si-Mui SIM ; Nor Mohd Adnan AZILA ; Lay-Hoong LIAN ; Christina P L TAN ; Nget-Hong TAN
Annals of the Academy of Medicine, Singapore 2006;35(9):634-641
INTRODUCTIONA process-oriented instrument was developed for the summative assessment of student performance during problem-based learning (PBL) tutorials. This study evaluated (1) the acceptability of the instrument by tutors and (2) the consistency of assessment scores by different raters.
MATERIALS AND METHODSA survey of the tutors who had used the instrument was conducted to determine whether the assessment instrument or form was user-friendly. The 4 competencies assessed, using a 5-point rating scale, were (1) participation and communication skills, (2) cooperation or team-building skills, (3) comprehension or reasoning skills and (4) knowledge or information-gathering skills. Tutors were given a set of criteria guidelines for scoring the students' performance in these 4 competencies. Tutors were not attached to a particular PBL group, but took turns to facilitate different groups on different case or problem discussions. Assessment scores for one cohort of undergraduate medical students in their respective PBL groups in Year I (2003/2004) and Year II (2004/2005) were analysed. The consistency of scores was analysed using intraclass correlation.
RESULTSThe majority of the tutors surveyed expressed no difficulty in using the instrument and agreed that it helped them assess the students fairly. Analysis of the scores obtained for the above cohort indicated that the different raters were relatively consistent in their assessment of student performance, despite a small number consistently showing either "strict" or "indiscriminate" rating practice.
CONCLUSIONThe instrument designed for the assessment of student performance in the PBL tutorial classroom setting is user-friendly and is reliable when used judiciously with the criteria guidelines provided.
Education, Medical ; methods ; standards ; Educational Measurement ; methods ; Humans ; Problem-Based Learning ; standards ; Retrospective Studies ; Students, Medical ; Surveys and Questionnaires ; standards