Brief problem-solving questions in medical school examinations: is it necessary for students to explain their answers?

OBJECTIVE: To compare outcomes when answers to objective type problem-solving questions are marked with and without consideration of students' explanations of their answers. DESIGN: Students answered six multiple-part problem-solving questions on the final examination for a course in clinical biochemistry. Each part required a choice from a list, a number or a few words, plus an explanation or justification. Scores were determined independently for the answers alone and for the answers plus explanations. The outcomes of the two marking methods were compared. SETTING: Department of Pathology, University of Otago Medical School, Dunedin, New Zealand. SUBJECTS: Final year preclinical medical students. RESULTS: Marks were slightly higher for answers alone than for answers plus explanations (overall mean, 82.1%; standard deviation, 9.8% vs. 77.1%; 9.3%; P < 0.001 by paired t-test). There was a very high correlation between scores derived from the two methods (r=0. 87). Consideration of the answers alone (without explanations) was about as good as answers plus explanations in identifying students who performed at different levels overall on the examination and in identifying the weakest students. CONCLUSIONS: The data suggest that when students arrived at the correct answers, their information and reasons were usually correct and that answers alone discriminate adequately among students with different levels of knowledge and ability. By dispensing with the requirement for explanations, we would be able to ask more questions and mark objectively, so competent students should not be disadvantaged by the lack of opportunity to explain their reasoning.

Curriculum reform at the University of Otago Medical School.

The University of Otago Medical School, the older of the two medical schools in New Zealand, identified during the 1980s many of the same problems with its undergraduate curriculum as were reported in the United States, Canada, and the United Kingdom. An early, overly ambitious attempt to introduce a full problem-based learning curriculum at Otago failed; however, many piecemeal changes that embodied some of the principles of problem-based learning were successfully implemented. Subsequently, as desire for more coordinated and substantive change grew, Otago's faculty used what they had learned from their first effort to successfully introduce a modular systems-based preclinical curriculum in 1997. The authors describe the features of the new curriculum and discuss two components (a systems-integration course and a large-scale program of computerized in-course testing) that are particularly innovative. The new curriculum is already achieving one of its main goals (increasing the perceived relevance of preclinical teaching) and other outcomes are being evaluated.

Pilot studies of in-course assessment for a revised medical curriculum: I. Paper-based, whole class.

PURPOSE: To test a paper-based method of in-course assessment for a modular, systems-oriented medical curriculum at the University of Otago Medical School. METHOD: In 1996, 193 students took paper-based quizzes on the first four topics of a course in clinical biochemistry. A score of 75% was required for passing, but students could retake quizzes. The subsequent test on these four topics was constructed from questions used in previous years. The next four topics were taught without quizzes. The test on these topics was again constructed from questions used in past years. The authors examined the performances on the quizzes and tests and sought the students' opinions about the program. RESULTS: 72.0-95.3% of the students passed the quizzes the first time and 94.8-99.5% passed by the second version. Performance on the subsequent test items was higher than [corrected] when the items had been used previously; so was performance on three of the four questions for the next four topics, none of which had been accompanied by quizzes. Students valued the quizzes as a stimulus to study and as feedback. They preferred the segment of the course with the quizzes to the segment without them. CONCLUSION: This method of in-course assessment was easy to administer and highly acceptable to the students. Performance on the quizzes was more than satisfactory and a passing score of 75% was reasonable. Such quizzes appeared to be able to replace a test that required explanation of answers while increasing the numbers of questions that could be asked and decreasing the marking time.

Pilot studies of in-course assessment for a revised medical curriculum: II. Computer-based, individual.

PURPOSE: To test a computer-based method of in-course assessment for a modular, systems-oriented medical curriculum at the University of Otago Medical School. METHOD: For the in-course assessment in anatomic pathology, 193 students completed five biweekly (i.e., every two weeks), criterion-referenced, computer-based quizzes incorporating many digitized photographs and a variety of question formats. The students signed up to take quizzes at any of ten available times during each quiz week. A score of 70% was required for passing each quiz, but the students could retake quizzes up to two more times in alternative versions. The students' opinions about biweekly testing and computer-based testing were sought. RESULTS: All 193 students satisfactorily completed the assessment program, with no significant problems with hardware, software, or administration during the more than 1,000 computer-based quizzes. The students valued the bi-weekly quizzes as a stimulus for study and for feedback. They strongly supported computer-based quizzes, identifying a variety of benefits in their responses to the questionnaire. The staff found that development of visually rich quizzes was greatly facilitated by the use of computers. CONCLUSION: The study confirmed the feasibility of using regular, computer-based quizzes for in-course assessment of a large medical school class and demonstrated assessments of a kind that would be difficult to achieve by means other than with computers.

Management of dislocated nuclear fragments after phacoemulsification.

We examined 13 patients referred for management of dislocated lens fragments after phacoemulsification. Ocular findings included corneal decompensation, glaucoma, inflammation, and retinal tears and detachments. Eleven of the 13 patients underwent vitrectomy with removal of lens fragments. Surgical indications included the presence of large lens fragments, uncontrolled glaucoma, persistent and severe inflammation, and retinal detachment. Better visual acuity was observed in patients who had smaller lens fragments or when vitrectomy was delayed to allow medical treatment of intraocular inflammation and glaucoma. The results indicate that nucleus dislocation during phacoemulsification is an important visual complication, with seven of the 13 patients having a final visual acuity of 20/80 or less.

Management of macular puckers associated with retinal angiomas.

Monocular visual loss in four patients was caused by epiretinal macular membranes associated with peripheral retinal capillary angiomas or angioma-like lesions. Three patients had solitary vascular lesions and one had two discrete vascular lesions. All patients were in good health, with no evidence of the von Hippel-Lindau syndrome. In three patients, spontaneous peeling of the macular membranes and visual improvement occurred 2 to 6 months after obliteration of the angioma-like lesions with cryotherapy (two patients), or cryotherapy combined with argon laser (one patient). The fourth patient underwent a vitrectomy 8 months after the macular pucker had failed to respond to treatment of the vascular lesion.

Peripheral retinal neovascularization in birdshot retinochoroidopathy.

A 69-year-old black woman had ocular findings consistent with birdshot retinochoroidopathy; these included cream-colored depigmented spots at the level of the retinal pigment epithelium and vitreitis. She also had peripheral retinal neovascularization with localized vitreous hemorrhage. There were no laboratory or systemic findings consistent with other disease entities.