Engineering topological states in atom-based semiconductor quantum dots.

The realization of controllable fermionic quantum systems via quantum simulation is instrumental for exploring many of the most intriguing effects in condensed-matter physics1-3. Semiconductor quantum dots are particularly promising for quantum simulation as they can be engineered to achieve strong quantum correlations. However, although simulation of the Fermi-Hubbard model4 and Nagaoka ferromagnetism5 have been reported before, the simplest one-dimensional model of strongly correlated topological matter, the many-body Su-Schrieffer-Heeger (SSH) model6-11, has so far remained elusive-mostly owing to the challenge of precisely engineering long-range interactions between electrons to reproduce the chosen Hamiltonian. Here we show that for precision-placed atoms in silicon with strong Coulomb confinement, we can engineer a minimum of six all-epitaxial in-plane gates to tune the energy levels across a linear array of ten quantum dots to realize both the trivial and the topological phases of the many-body SSH model. The strong on-site energies (about 25 millielectronvolts) and the ability to engineer gates with subnanometre precision in a unique staggered design allow us to tune the ratio between intercell and intracell electron transport to observe clear signatures of a topological phase with two conductance peaks at quarter-filling, compared with the ten conductance peaks of the trivial phase. The demonstration of the SSH model in a fermionic system isomorphic to qubits showcases our highly controllable quantum system and its usefulness for future simulations of strongly interacting electrons.

Controversial beliefs about diabetes and its care.

OBJECTIVE: The purpose of this study was to identify specific beliefs that differentiate health-care professionals whose attitudes toward diabetes agreed most strongly with a group of national diabetes experts from those whose attitudes disagreed most strongly. RESEARCH DESIGN AND METHODS: The sample for this study included 271 physicians, 834 nurses, and 546 dietitians who completed a Diabetes Attitudes Survey. The sample included specialists in diabetes care and nonspecialists. Controversial beliefs about diabetes and its care were determined by comparing the beliefs of the 10% of the sample whose attitudes were most concordant (with the national panel) with the beliefs of the 10% of the sample whose attitudes were the most discordant. Ten beliefs met the criteria for being defined as controversial. RESULTS: The most controversial beliefs concerned whether the patient or the physician should be the primary decision maker in diabetes care, the meaning of patient noncompliance, and the seriousness of non-insulin-dependent diabetes mellitus. The 10% of the sample with the most discordant attitudes contained a disproportionately large number of physicians, nonspecialists in diabetes, and health-care professionals who had been in practice longer than the other members of the sample. CONCLUSIONS: This study identifies some important differences in beliefs between younger health-care professionals who specialize in diabetes and older nonspecialists. Such beliefs should be addressed in continuing education programs with the aim being to foster the widespread adoption of a contemporary approach to diabetes care.

Development of diabetes attitude scale for health-care professionals.

This article describes the development of a diabetes attitude scale (DAS) that was designed to measure the attitudes of health-care professionals (HCPs). The DAS was developed through the efforts of a national panel of diabetes experts. The panel developed a 60-item scale that was pilot tested and reduced to a 50-item scale. The 50-item scale was then mailed to a national sample of HCPs with an interest in diabetes. The surveys were returned by 633 nurses, 322 dietitians, 116 physicians, and 67 others totaling 1138 returns (a return rate of 54%). The returned surveys were analyzed, and a 31-item DAS composed of 8 subscales resulted. Evidence for the reliability and validity of the 31-item DAS along with the instrument itself are included in this study.

Influencing the attitudes of medical students toward diabetes. Results of a controlled study.

OBJECTIVE: To determine the effect of two educational interventions on the diabetes-related attitudes of medical students. RESEARCH DESIGN AND METHODS: We studied 67 junior and senior medical students who were participating in the University of Michigan Medical School's Family Practice elective clerkship. Students were assigned to one of two interventions. The first was a 1-wk living-with-diabetes behavioral simulation that involved injections, blood glucose monitoring, diet, exercise, and record keeping. The second intervention involved reading an autobiography about living with diabetes and viewing a videotape about the psychosocial impact of diabetes. RESULTS: No differential impact was found between the two interventions. However, both interventions were followed by a modest positive change in the attitudes of the medical students (which were very positive to begin with) toward the importance of patient autonomy and the value of the team approach to diabetes care. The attitude gains persisted at follow-up for patient autonomy but returned to baseline for team care. CONCLUSIONS: This study suggests that these two educational interventions resulted in modest increases in the already positive attitudes of medical students toward the importance of patient autonomy and team care in diabetes. However, because the study did not include a group that received no treatment, we cannot be certain on this point. The attitude gain related to team care did not persist at follow-up. These findings are consistent with classical attitude research, which suggests that attitudes are sensitive to influences such as these interventions, but that attitude changes may not persist when those influences are changed or withdrawn. We were not able to find a differential impact between the two interventions and suspect that the general nature of the DAS used as the dependent measure may not have been sensitive enough to capture such a differential impact.

Cancer pain assessment and management by housestaff.

Pain control for cancer patients is a significant problem in health care, and lack of expertise by clinicians in assessing and managing cancer pain is an important cause of inadequate pain management. This study was designed to use performance-based testing to evaluate the skills of resident physicians in assessing and managing the severe chronic pain of a cancer patient. Thirty-three resident physicians (PGY 1-6) were presented with the same standardized severe cancer pain patient and asked to complete a detailed pain assessment. The residents then completed questions related to management of the cancer pain patient. In the cancer pain assessment, residents did well in assessing pain onset (70%), temporal pattern of pain (64%), and pain location (73%). However, only 33% and 45% physicians adequately assessed the pain description and pain intensity, respectively, and assessment of pain-relieving factors, previous pain history, and psychosocial history was done poorly or not at all by 70%, 88%, and 94% of residents. Only 58% of the residents were judged to be competent in this clinical cancer pain assessment. In the cancer pain management section, opioid analgesic therapy was prescribed by 98% of residents, and 91% used the oral route. However, only 18% of prescriptions were for regular use and 88% of residents did not provide analgesics for breakthrough pain. A significant number of graduated physicians were judged to be not competent in the assessment and management of the severe pain of a standardized cancer patient. Opioids and NSAIDs were the analgesics of choice; however, most were prescribed on a PRN basis only. Co-analgesics were rarely prescribed. Few physicians managed persistent, severe cancer pain according to the WHO guideline of increasing the opioid dose. The lack of significant difference in scores between junior and senior residents suggest that adequate cancer pain management is not being effectively taught in postgraduate training programs.

Informed consent for bone marrow transplantation: identification of relevant information by referring physicians.

Two hundred Michigan hematologists-oncologists were sent a 34-item questionnaire designed to assess what patients should know at the time of giving consent to bone marrow transplant (BMT). Sixty-three (32%) responded to a single mailing and rated items on a 8-point scale, varying from 0 = no need to know to 7 = appreciation of consequences essential. The mean rating across items was 5.2, indicating that all items were important. Statistically, the items separated into three groups: (1) above average importance - 13 items; (2) average importance - 9 items; (3) below average importance - 12 items. Items of above average importance included the rationale for BMT and the collective risks and benefits of the process, including the patient's well-being post-transplant. Informed consent documents did not include 5/13 items of above average importance, yet 12/21 items of average and below average importance were included. Fourteen demographic variables were correlated with each item and none were significant, indicating that the ratings represent a broad consensus in the referring physician community as to what a patient should understand before consenting to BMT. The vast majority of referring physicians agreed that patients usually have an adequate understanding of BMT at the time of giving informed consent and that a fully informed patient is more likely to adhere to the treatment regimen.

Assessing senior residents' knowledge and performance: an integrated evaluation program.

BACKGROUND: Surgical residents have traditionally been evaluated by ward evaluations and multiple-choice testing; overall resident performance has seldom been objectively evaluated. We developed a comprehensive evaluation program for senior residents. The purpose of this study was to determine whether the several different assessment methods included in this program provide similar information about senior residents' clinical knowledge and performance. METHODS: Sixteen senior general surgery residents were evaluated by subjective faculty ward evaluations, a structured oral examination, the American Board of Surgery In-Training Examination, and an objective structured clinical examination (OSCE). The OSCE was divided into two parts: part A required the resident to obtain a directed history or to perform a physical examination; part B required the resident to answer questions about the patient seen in part A. RESULTS: The various evaluation methods differed in their estimates of clinical competence (ward evaluations rated residents highest; the OSCE, lowest). The American Board of Surgery In-Training Examination correlated with both the structured oral examination and OSCE part B, indicating that all are adequate measures of knowledge. Neither the total OSCE score nor OSCE part A correlated with other measures, but the fact that both are highly reliable suggests that they evaluate different clinical skills. Faculty ward evaluations are inflated and do not correlate with other measures. CONCLUSIONS: We conclude that developing a comprehensive program for evaluating resident competence is desirable and feasible.

Use of an Objective Structured Clinical Examination (OSCE) to measure improvement in clinical competence during the surgical internship.

BACKGROUND: Traditional ward ratings and multiple-choice tests do not reliably assess clinical competence. This study determined the reliability of the Objective Structured Clinical Examination (OSCE) and its sensitivity in detecting the performance gains and deficits in surgical interns. METHODS: A comprehensive 35-station OSCE was administered to 23 incoming interns and seven outgoing interns. The OSCE comprised 17 two-part clinical problems, relying primarily on actual or simulated patients. The reliability of the examination was assessed by coefficient alpha. Significant differences in performance between the two intern groups, between parts A and B, and among the 17 problems were determined by a three-way ANOVA: OSCE performance was also correlated with National Board of Medical Examiners Part II scores. RESULTS: The reliabilities of part A, part B, and parts A and B combined were 0.72, 0.70, and 0.82, respectively. Overall, the outgoing interns performed significantly better than the incoming interns: 58% +/- 1% mean OSCE score versus 47% +/- 1% (p = 0.0001). The 17 clinical problems differed significantly in difficulty; major performance deficits were seen in both groups of trainees. The correlation of OSCE scores with National Board of Medical Examiners Part II scores was not significant (r = 0.11, p = 0.633). CONCLUSIONS: We conclude that the OSCE is an innovative, reliable tool for evaluating resident competence. Although outgoing interns performed better than did incoming interns, the OSCE scores clearly indicated major performance deficits in all interns.

Defining the surgical personality: a preliminary study.

Noting that noncognitive factors may be more predictive of success in a medical career than is intellectual ability or cognitive performance, we undertook a study to determine whether a surgical personality exists and to delineate the temperament and personality traits that contribute to its definition. The Krug Adult Personality Inventory, the Strelau Temperament Inventory, and Barclay's adjective checklist were administered to 110 physicians, 35 in a "controllable lifestyle" specialty, 28 in primary care, and 47 in surgery or a surgery subspecialty. In addition, participants completed a stress inventory. Results showed that surgeons form a distinct and homogeneous group based on temperament and personality traits. We suggest that noncognitive factors can be of use to medical educators in the selection, counseling, training, and evaluation of medical personnel.

Assessing residents' clinical performance: cumulative results of a four-year study with the Objective Structured Clinical Examination.

BACKGROUND: The Objective Structural Clinical Examination (OSCE) is an objective method for assessing clinical skills and can be used to identify deficits in clinical skill. During the past 5 years, we have administered 4 OSCEs to all general surgery residents and interns. METHODS: Two OSCEs (1993 and 1994) were used as broad-based examinations of the core areas of general surgery; subsequent OSCEs (1995 and 1997) were used as needs assessments. For each year, the reliability of the entire examination was calculated with Cronbach's alpha. A reliability-based minimal competence score (MCS) was defined as the mean performance (in percent) minus the standard error of measurement for each group in 1997 (interns, junior residents, and senior residents). RESULTS: The reliability of each OSCE was acceptable, ranging from 0.63 to 0.91. The MCS during the 4-year period ranged from 45% to 65%. In 1997, 4 interns, 2 junior residents, and 2 senior residents scored below their group's MCS. MCS for the groups increased across training levels in developmental fashion (P < .05). CONCLUSIONS: Given the relatively stable findings observed, we conclude (1) the OSCE can be used to identify group and individual differences reliably in clinical skills, and (2) we continue to use this method to develop appropriate curricular remediation for deficits in both individuals and groups.

Improving residents' clinical skills with the structured clinical instruction module for breast cancer: results of a multiinstitutional study. Breast Cancer Education Working Group.

BACKGROUND: The purpose of this study was to determine, in a multiinstitutional setting, the effectiveness of the structured clinical instruction module (SCIM) as an instructional format for surgical residents. METHODS: The breast cancer SCIM is an abbreviated (3-hour) clinical skills course that places residents in realistic clinical settings. The curriculum encompasses all aspects of breast cancer patient assessment. The SCIM was administered to 137 residents at five institutions. Sixty-six faculty members and 52 patients participated. All participants were surveyed with multiitem questionnaires. The residents were also asked to perform a self-assessment of their skills before and after the SCIM. RESULTS: The SCIM was delivered at all institutions without difficulty. All participants rated the SCIM highly (from "above average" to "outstanding"). Mean ratings (on a 5-point scale) for the overall effectiveness of the SCIM as an educational format follow: [table: see text] The pretest mean (on a 5-point scale) on the self-assessment was 2.46 ("less than competent"); the posttest mean was 3.54 ("more than competent") (p < 0.0001). CONCLUSIONS: Residents are acutely aware of their deficiencies in understanding breast cancer. The SCIM is a standardized, reproducible, portable, and effective educational vehicle.

Cancer pain education among family physicians.

This study used performance-based testing (objective structured clinical evaluation, OSCE) to evaluate the skills of family physicians in assessing and managing the severe pain of a cancer patient, and evaluated a new method of education about the management of cancer pain. Twenty-four primary care physicians completed a detailed pain assessment of the same standardized cancer pain patient (Part A). A proctor observed the interviews and rated the physicians on a variety of pre-determined items believed to be important for pain assessment. The physicians were then allowed 5 min to answer management questions about the patient's cancer pain (Part B). After reviewing each physician's performance on Parts A and B, the proctor provided immediate feedback and instruction (Part C) on basic principles of cancer pain assessment and management. On average, the primary care physicians asked 52% (+/-4.5%) of the indicated questions of a detailed pain assessment. Performance was poorest in asking about previous pain history, temporal pattern of pain, and pain intensity. Performance on the pain assessment was best for eliciting pain location and pain-relieving factors. Primary care physicians obtained mean scores of 36% (+/-3%) on Part B of the OSCE. Although opioid therapy was frequently prescribed, only 42% of prescriptions were for regular administration. Performance on Parts A and B correlated poorly with years in practice, and older physicians tended to perform a less detailed pain assessment than their younger colleagues. Most physicians enjoyed participating in this instructional formal and believed that the proctor feedback increased the educational value of the module. The results of our study suggest that many family physicians may be inadequate in their clinical assessment and management of cancer pain. Our study supports the need for continuing education in cancer pain management, regardless of years in practice. Further study should evaluate the effects of different educational programs on clinical practice in patient care.

Evaluation of clinical instructors by third-year medical students.

Third-year medical students used 12 descriptive items to evaluate the teaching skills of first-year residents, senior medical residents, preceptors (internal medicine fellows), and attending physicians. Intraclass correlations showed that the students were able to judge their instructors reliably. Further analyses were then carried out to determine whether students differentially evaluated the four instructor groups. Three of the descriptive items that related to overall evaluations, as well as the mean rating of all items, indicated no group differences. However, when the groups were compared on specific teaching characteristics (by means of a multiple-group discriminant function analysis), systematic differences were found. The first function differentiated the groups in terms of the cognitive and experiential characteristics of the instructors, with attending physicians being rated the highest and first-year residents the lowest. In contrast, the third function separated the groups in terms of interpersonal skills; on this function, the senior medical residents were rated the highest and preceptors the lowest. It is concluded that students make sophisticated judgments in evaluating their clinical teachers.

Knowledge gain in a problem-based surgery clerkship.

PURPOSE: To determine the magnitude of students' knowledge gain in a problem-based surgery clerkship and to identify the relationship of this gain to measures of clinical performance. METHOD: Third-year students in a problem-based surgery clerkship at the University of Kentucky College of Medicine in 1990-91 were evaluated by a comprehensive set of objective measures: surgery subject examinations of the National Board of Medical Examiners (NBME) given as pretest and posttest to assess knowledge gain, two multiple-choice quizzes, a modified-essay examination, a standardized-patient examination, and an objective structured clinical examination (OSCE). The students were also evaluated by faculty tutors and preceptors and by their peers. NBME data were available for 66 students, and data were available on the other measures for 42 students. Statistical analysis involved two-way analysis of variance, single group t-test, Pearson correlations, and partial correlations. RESULTS: The students' knowledge gain was statistically significant. The posttest mean score did not differ significantly from the national candidate mean of 500. All but two of the other knowledge and performance measures (the preceptor and tutor evaluations) correlated significantly with the knowledge gain score. The highest correlations were for peer evaluations, the standardized-patient examination, and the modified-essay examination. The overall reliability of the eight measures of student knowledge and performance was .81; deleting any measure, except the preceptor evaluation, lowered the reliability below the benchmark of .80. CONCLUSION: The results suggest that a highly significant knowledge gain occurred during the problem-based clerkship and that this gain in knowledge was closely related to improved clinical performance.

Developing students' cognitive skills in a problem-based surgery clerkship.

In 1989-90, 57 students in a new program for the third-year surgery clerkship at the University of Kentucky College of Medicine participated either in a control group (22 students) receiving a traditional method of instruction (Socratic instruction, SI) or in an experimental group (35 students) taking part in problem-based learning (PBL) sessions. The two groups' performances on six evaluative instruments designed to test either their factual knowledge or their knowledge application (i.e., clinical problem-solving skills) were compared. The measures of factual knowledge were associated with higher scores for the SI group on two quizzes; scores were not significantly different on another quiz and on a cumulative final examination. The measures of knowledge application (administered at the end of the clerkship) were associated with higher scores for the PBL group: scores were significantly higher on a modified essay examination and approached significance on a standardized-patient examination. The authors conclude that their results (1) have important similarities to those of previous research suggesting that a PBL format is essentially equivalent to a traditional curricular format in improving students' factual knowledge and (2) support the hypothesis that PBL is superior in improving clinical problem-solving skills.

Stability of medical specialty selection at the University of Kentucky.

In the fall of 1989, all graduates of a 30-year-old medical college were surveyed by questionnaire concerning their motivations for their original selections of specialties, motivations for changing their specialties when such changes had occurred, and factors involved in their current choices of specialties. The 723 respondents were grouped by specialty response into one of three groups (primary care plus medicine and pediatrics subspecialties; surgery; or controllable lifestyle), and responses were statistically analyzed. The most important factors influencing initial specialty selection were perceived match of personality and specialty; technology and methodology characteristic of the specialty; and time for family activities, in that order. The ratings of the 175 respondents who stated that they had changed specialties indicated that time for avocational pursuits and time for family activities were the most important reasons for change. The reasons for selecting a different specialty varied. This study's findings suggest that a student's likelihood of making an inappropriate specialty choice may be reduced by a broad undergraduate medical education with realistic experiences in clinical activity. Students' lack of awareness of the lifestyle of a particular specialty may be a significant factor in the flow of physicians from noncontrollable lifestyle specialty areas. Those who counsel medical students need to be aware of the increasing importance of controllable lifestyle features, changing attitudes, faculty role-modeling, and mentors as strong influences on students' choices of specialties.

The characteristics of early diagnostic hypotheses generated by physicians (experts) and students (novices) at one medical school.

How hypotheses generated at the outset of a physician-patient encounter influence the physician's diagnostic reasoning has received relatively little attention in the literature. Yet, this activity modulates the efficiency and accuracy of the diagnostic process. The authors proposed the theory that physicians (experts) would generate less specific initial diagnostic hypotheses than would students (novices). In 1988 and 1989, the hypotheses generated by 32 practicing physicians and 39 third-year medical students at one medical school were analyzed for number, specificity, and breadth (i.e., range) of diagnoses, and for differences between those generated by the physicians and by the students. The hypotheses were formulated on the basis of the initially available data--chief complaint and its duration, and basic demographic descriptions--from patients in three clinical scenarios. Compared with the physicians, the students generated significantly more hypotheses and significantly more specific hypotheses. There was no significant difference between the groups in the breadths of the hypotheses they selected, that is, the numbers of broad categories of diagnosis covered by individuals' hypotheses.

Changes in the patterns of specialties selected by high and low academic performers before and after 1980.

BACKGROUND: The goal of this study was to examine whether recently observed changes in the distribution of medical school graduates' choices are linked to level of academic achievement, graduation year, or both. METHOD: The authors studied the specialty selections made by two groups of graduates of the University of Kentucky College of Medicine: 319 who were elected to Alpha Omega Alpha and 276 who ranked academically in the bottom 10% of their classes. They also divided the groups into two time frames: 1964-1979 and 1980-1991. Two-way factorial analyses of variance compared the distributions of specialty selections according to time frame and to academic group. RESULTS: Significantly higher percentages of students in the low-achievement group selected primary care specialties (F = 14.76, p < .001), and this difference between the academic groups increased in recent years: 67% versus 41% in 1980-1991 compared with 53% versus 46% in 1964-1979. CONCLUSIONS: The specialty options most readily available to academically low-achieving medical school graduates are narrowing. Low achievers may be funneled into primary care simply because they cannot compete for other specialties. The authors recommend that: (1) recruitment and selection into primary care specialties should be made only after each candidate has been assessed over a broad range of cognitive and noncognitive factors and (2) academically low-ranking graduates should not end up in primary care specialties simply because no other specialty options are available to them.

The reliability of six faculty members in identifying important OSCE items.

PURPOSE: To measure the agreement among faculty members about the importance of items on a checklist used to grade an objective structured clinical examination (OSCE) station. METHODS: Six faculty members rated the importance of 47 items for an OSCE station in which students took the history of a patient with sore throat and hoarseness. RESULTS: Of the 47 items, the raters independently identified 15 items as very important. The reliability of each individual rater was fair (averaged value of alpha = .63.) The reliability of the mean rating of the six raters was high (alpha = .91). CONCLUSIONS: The results strongly suggest that when a group of faculty members cooperatively identifies the important items to be included in an OSCE checklist, the reliability of the checklist is superior to one created by a single author.

Demographic, educational, and psychosocial factors influencing the choices of primary care and academic medical careers.

PURPOSE: To identify demographic, psychosocial, and educational variables that differentiate physicians who have chosen careers in primary care from those who have chosen academic medicine. METHOD: Questionnaires were distributed in the spring of 1992 to 704 physicians (546 in primary care practices and 143 in academic medicine) who had graduated from the University of Kentucky College of Medicine, 1964-1991. Mann-Whitney U tests and analyses of variance were used for statistical comparisons. RESULTS: A total of 336 physicians responded: 246 in primary care and 90 in academic medicine. The primary care physicians tended to come from smaller cities than did the academic physicians (p < .0001). The primary care physicians also had made their career choices earlier than did the academic physicians (p < .0001). For the academic physicians, long-term participation in research, intellectual stimulation, content of specialty, and influence of a mentor or role model were significantly more important factors than they were for the primary care physicians, for whom length of training, direct patient contact, and threats of malpractice suits were significantly more important. CONCLUSION: The results corroborate the findings of previous studies that suggest that career-choice factors are influenced by admission procedures and curricular structures. The number of graduates choosing careers in either primary care or academic medicine may be increased by increasing their experiences in those fields. Medical schools may be able to use demographic, psychosocial, and curricular factors to fulfill their particular primary mandates, whether they be producing physicians in primary care or in academic medicine.