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N V Vu

Publications and source records attributed to N V Vu.

11 recordsLinked to original sources
PubMed1992

Six years of comprehensive, clinical, performance-based assessment using standardized patients at the Southern Illinois University School of Medicine.

By the end of 1990-91, the Southern Illinois University School of Medicine had had six years of experience with comprehensive, performance-based examinations of senior medical students' levels of clinical competence; this report assesses the psychometric aspects of the six examinations given during that period. The examinations were aimed at determining the students' readiness for postgraduate training. Compared with other clinical performance-based assessments that use standardized patients (SPs), these examinations had two important and unique features: (1) the examinations assessed a comprehensive range of clinical skills and reasoning; and (2) they approximated the challenges of real clinical practice wherein a practitioner's skills need to be orchestrated and prioritized in order to meet the challenges of the case encountered. Each year, the performance-based assessment given was an intensive clinical examination requiring each student to work up 13 to 18 SP problems over a three-day period. To administer an examination to an entire class of students took three weeks. Because all students after the first year of administration (1986) were required to pass these examinations, the fairness of test design and scoring and the setting of performance standards for the examinations became important issues for the faculty. The results, accumulated over six years and based on a total of 6,804 student-patient encounters involving 405 students, indicate that this kind of clinical performance-based examination can discriminate a wide range of students' clinical performances. The results provide evidence for the examinations' test security, content validity, construct validity, and reliability.

Clinical Clerkship↗
PubMed1992

Screening test length for sequential testing with a standardized-patient examination: a receiver operating characteristic (ROC) analysis.

The feasibility of using sequential testing (i.e., using a screening test) to reduce the length and expense of a performance-based examination with standardized-patient cases was demonstrated previously. In the present study, quantitative criteria rather than practical considerations were used to determine optimal values for the length of the screening test (i.e., number of cases) and the location of the screening pass-fail cutoff (i.e., its relation to the mean of the pass levels for the different cases). Data were derived from five classes of senior students at the Southern Illinois University School of Medicine, 1987-1991. Specifically, receiver operating characteristic (ROC) curves were plotted for screening tests of varying lengths, with the points on each ROC curve corresponding to different pass-fail cutoffs on the screening test. The results showed that good accuracy can be attained with a screening test that is only one-third the length of the full examination and that the cutoff for this screen should be set slightly above the mean of the case pass levels to maximize sensitivity and specificity. The authors conclude that their study demonstrates the value of an ROC analysis in evaluating the psychometric properties of a screening test in sequential testing.

Clinical Clerkship↗
PubMed1992

Standardized (simulated) patients' accuracy in recording clinical performance check-list items.

In large-scale performance-based assessment of medical professionals' clinical competence, simulated patients (standardized patients-SPs) are used not only to simulate case problems but also to record on check-list the examinees' clinical performance during their encounter with the SPs. The purposes of this study were to determine the SPs' overall accuracy in recording check-list items, and whether their accuracy was affected by the various characteristics of the check-list, and by the different times during a day and the different days within the examination when the recordings were obtained. Results showed that the SPs' accuracy in recording check-list items was good to very good and was affected by the length of the check-list, as well as by the type and the clarity of the check-list item. It was further found that the SPs' accuracy was consistent and did not vary over the course of a one-day or a 15-day examination.

Clinical Competence↗
PubMed1991

Test security in examinations that use standardized-patient cases at one medical school.

The use of performance-based examinations consisting of standardized-patient (SP) cases has increased greatly in recent years. These examinations are typically long and thus require the presentation of the same SP cases to several consecutive examinee groups. Consequently, concerns have arisen about the potential for violations of test security whereby students who were tested early in the examination period pass on information to students tested later. These concerns are addressed using data from the SP-based examinations administered to five classes (1986-1990) of senior medical students at Southern Illinois University School of Medicine. Because of the length of the examinations, each class was randomly divided into five groups and the examination was administered to one group at a time, requiring three days of testing time per group and three weeks of testing time per class. The results showed no consistent, systematic changes in case means across the five groups tested at different times throughout the examination period, and thus provide no evidence of serious, widespread violations of test security.

Education, Medical↗
PubMed1991

Effects of using two or more standardized patients to simulate the same case on case means and case failure rates.

The effects of using two or more standardized patients (multiple SPs) to simulate the same case in a performance-based examination were studied at the case level by comparing case means and case failure rates for multiple SPs simulating the same case, using data from the classes of 1988, 1989, and 1990 at the Southern Illinois University School of Medicine. For total scores and scores on the students' written answers, the effects on means and failure rates were negligible and could be explained as due to sampling error. For scores on the checklists completed by the SPs, there were more significant differences than would be expected by chance alone, even though the number of significant differences was relatively small. The results demonstrate a need for caution in the interpretation of scores obtained from a case checklist completed by multiple SPs, particularly in regard to making pass-fail decisions.

Achievement↗
PubMed1991

Reliability and efficiency of components of clinical competence assessed with five performance-based examinations using standardized patients.

The present study was conducted to provide in-depth information on the reliabilities of measures of the separate components of clinical competence (e.g. data collection, test interpretation, diagnosis, etc.) assessed by a performance-based examination consisting of standardized-patient cases administered to five classes of senior medical students at Southern Illinois University School of Medicine. In general, the reliabilities of the competencies as they were actually measured on the examination (using the number of cases on which each competency was actually measured) were small, with 54% less than 0.30 and 75% less than 0.40. For generalizability coefficients pooled across the five classes and projected to a common number of k = 10 cases, two of the nine competencies had reliabilities in the 40s, a third was close to 0.40, and the remaining six were in the low 20s. The number of cases needed for the competencies to achieve the recommended reliability of 0.80 ranged from 45 to 170 cases, with six of the nine competencies requiring over 100 cases to reach the 0.80 level. The low reliabilities of these measures of the components of clinical competence raise serious questions about using the scores as indicators of student performance.

Clinical Clerkship↗
PubMed1988

The use of performance-based assessment scores and traditional measures in predicting first-year residency performance.

The purpose of this study is to examine the relationship between students' performance on a performance-based clinical examination and their subsequent performance during the first year of residency. Additionally, its purpose is to further examine the relationship between the performance-based clinical examination and existing measures of clinical competence (clerkship ratings, and NBME Part I and II scores).

Clinical Clerkship↗