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1 From the Division of Health Promotion Sciences, University of Arizona, College of Public Health, Tucson; the Department of Family and Community Medicine and the Division of Academic Resources, University of Arizona, College of Medicine, Tucson; Pima Community College, Tucson; and the Kaiser Center for Health Research, Portland, OR.
2 Supported in part by a grant (R25-CA53495) from the National Cancer Institute. 3 Address reprint requests to DL Taren, University of Arizona, College of Public Health, Box 245163, Tucson, AZ 85724. E-mail: taren{at}u.arizona.edu.
ABSTRACT
Background: Ninety-eight percent of medical schools report nutrition as a component of medical education. However, most schools do not have an identifiable nutrition curriculum. Medical schools that do include nutrition have not evaluated its effect on clinical skills.
Objective: The objective was to determine the efficacy of an integrated undergraduate medical curriculum to increase the quantity of nutrition instruction and to advance nutrition clinical skills demonstrated by medical students.
Design: A quasiexperimental design was constructed to determine whether an integrated nutrition curriculum increased the performance on nutrition-oriented clinical examinations of medical school classes that received 1, 2, or 3 y of the curriculum. The evaluation of the curriculum focused on 3 areas: 1) hours of nutrition instruction, 2) the application of nutrition within a clinical setting, and 3) perceptions about the nutrition curriculum. The Objective Structured Clinical Examination (OSCE) nutrition score was compared between graduating classes by use of analysis of variance. Data from the American Association of Medical Colleges were analyzed to determine the change in the proportion of students who reported that the amount of time devoted to nutrition was adequate.
Results: The implementation of the integrated nutrition curriculum resulted in a doubling of the total hours of required instruction in the medical curriculum (35 compared with 75 h). The mean (±1 SEM) OSCE nutrition score significantly improved after the implementation of the curriculum (41.7 ± 0.9% compared with 50.6 ± 1.1%) and the percentage of students who reported that the amount of nutrition taught during medical school was inadequate decreased (68.4% compared with 11.5%).
Conclusion: Medical students improved their clinical nutrition practice skills through participation in an integrated nutrition curriculum.
Key Words: Medical education • nutrition education • curriculum evaluation • medical school curriculum
INTRODUCTION
Nutrition training for medical students is identified as an important part of medical education by several organizations, including the American Society for Clinical Nutrition (ASCN), the American Medical Student Association (AMSA), and the National Academy of Sciences (NAS) (1–3). However, many medical schools do not provide 25 h of nutrition education, which is the minimum recommended by the NAS in 1985 (3). The NAS Council on Medical Education (4) recently reported that, although 98% of US medical schools offered at least one educational experience in nutrition in 1996–1997, comprehensive education in this area appears to be infrequent. Furthermore, 62.6% of 1994 graduates from US medical schools reported that they received an inadequate amount of nutrition education during their undergraduate training (5). This situation is an international issue and European educators have published similar concerns about the inadequacy of medical-nutrition education (6). In addition, outcome-based research on the amount, quality, and effectiveness of nutrition education is limited.
There is a long history of a concerted effort to include more nutrition education in the curricula of medical schools (7–10). These efforts have had variable success, and nutrition is continually being addressed as an area in need of an applicable model (11–13). Several organizations have recommended nutritional competencies for graduating medical students (1, 2, 14). For example, preventive and therapeutic nutrition competencies were published in 1983 (15), and the ASCN recommended 26 essential topics and 14 additional nutrition-related topics for the medical school curriculum (1). In 1996 the AMSA approved 92 nutrition topics within biochemistry, physiology, pathophysiology, nutrition assessment, diet and prevention, nutrition and disease, and nutrition therapy (2).
The National Cancer Institute (NCI) R25 training program has supported the development of nutrition education programs in medical schools. This support has allowed medical schools to create nutrition materials and to use a variety of channels to deliver nutrition information to medical students. These projects have included the creation of new nutrition courses, interactive multimedia educational materials, and clerkship nutrition handbooks. The current study was conducted to evaluate the integrated nutrition education program developed at the University of Arizona (UA) College of Medicine (COM).
SUBJECTS AND METHODS
Subjects
The nutrition curriculum described in this report was implemented at the UA COM. The project was initiated in 1993 and fully implemented in 1997. Less than 100 students were enrolled in each graduating class. Enrollment was on average 51% men and 49% women. The ethnic composition of the average class was 67% white, 10% Hispanic, 11% Asian, 3% African American, and 9% other. The mean age of the students was 24 y (range: 18–45 y).
Methods
The methodology for the development and implementation of the integrated nutrition curriculum at the UA COM was previously published (16). The curriculum did not comprise a single nutrition course but rather integrated nutrition content in required courses throughout the 4 y of the undergraduate medical studies. The focus of the methodology described here is the evaluation of the nutrition curriculum.
Nutrition curriculum
To determine changes in total hours of nutrition content, we performed an analysis in each course to identify the nutrition content before and after the development and implementation of the nutrition curriculum. Briefly, each course syllabus, including all 7 basic science courses and 5 required clerkship lectures, was reviewed for potential nutrition content. A nutrition professional attended all course presentations in which potentially nutrition-related content was presented and recorded the time dedicated to nutrition-specific content. Next, a meeting was held with the 16 faculty members teaching the content to more explicitly define the nutrition objectives and to determine the potential and the process for expanding the nutrition content. Last, the new or revised nutrition content was integrated into the course materials and instruction. As the curriculum was being developed, we tracked the new nutrition content for annual reports to the National Institutes of Health and to the UA COM curriculum committee. This comprehensive and integrated approach allowed the nutrition component of the curriculum to be taught throughout all 4 y of medical education. The number of hours that nutrition content was taught in each class was calculated after the integrated approach was implemented. The hours were then compared with the baseline number of hours of nutrition content in each course.
To determine the recent nutrition content, the course directors were contacted by telephone and were interviewed about their perception of current content and specifically asked about previously introduced curriculum. On the basis of these interviews, a summary of the current content was developed. The results of this review were verified independently through an interview with the research team that had just completed a review of course content as part of a project to integrate a cancer prevention curriculum into the UA COM.
Evaluation outcome measures
Evaluation of the nutrition curriculum project entailed 3 primary outcomes. The first evaluation included an inventory of the nutrition topics included throughout medical training before and after development of the integrated nutrition curriculum. The second evaluation technique measured applied skills in the area of nutrition with use of the Objective Structured Clinical Examination (OSCE). The third evaluation method used the postgraduation questionnaire for student evaluation of curriculum nutrition content and adequacy thereof conducted by the American Association of Medical Colleges (AAMC).
The complete curriculum was implemented during the spring of 1993. This implementation allowed us to use a quasiexperimental design to evaluate the curriculum by comparing different graduating classes that were exposed to various amounts of the curriculum. The graduating classes of 1994 (CL94) and 1995 (CL95) were exposed to a minimal amount of the integrated nutrition curriculum, primarily during their clinical practice education. These graduating students were compared with the classes of 1997 and 1998 (CL97 and CL98), who received the nutrition curriculum as an integrated component of both their basic science training and their clinical practice training.
Objective Structured Clinical Examination
The OSCE has been widely used in medical education to evaluate clinical skills among medical students and practitioners (17–20). This evaluation tool has a multistation format that uses standardized, trained patients to evaluate the performance of a wide range of clinical skills. The OSCE is administered to UA medical students at the beginning of their 4th year of medical school. The final nutrition OSCE score available for this evaluation was conducted in the summer of 1997 for CL98. The examination is required, and students must pass the examination to receive a passing status for medical school. The examination consists of 16 clinical stations through which the student rotates. Each station is timed. Selected station interactions are video or audio recorded to maintain continuous quality improvement standards. The overall mean OSCE scores at the UA COM have been stable over the past 5 y, ranging from 61% to 64%.
Historically, only an overall OSCE score for all items on the examination was calculated. With the development of the nutrition curriculum and the desire to use the examination to evaluate applied nutrition skills came the need to identify specific nutrition items for testing and scoring. Nutrition items were identified through independent reviews of all items by 3 independent clinicians—a physician, a registered dietitian, and a nutrition researcher. If all 3 professionals identified an item as nutrition, it was included in the computation of the overall nutrition score. If consensus was not achieved on an item, it was not included. Students were not aware at any time that a nutrition score for their performance would be calculated.
The OSCE nutrition scores were determined for 5 consecutive graduating classes (CL94, CL95, CL96, CL97, and CL98). Overall clinical performance on the nutrition items is expressed as the percentage of all possible points.
Medical School Graduation Questionnaire
The AAMC administers the Medical School Graduation Questionnaire each fall (5). The 37-item questionnaire is completed by graduating students during their final semester of medical school and is returned to the AAMC for scoring. All results are tabulated and distributed to the participating schools. Of interest to us was the student response to the question, "Do you believe that the time devoted to your instruction in nutrition was inadequate, appropriate, or excessive?" Historically, most medical students at the UA and nationally reported that the amount of instruction in nutrition was inadequate. We were interested to see whether the nutrition curriculum implemented at the UA would result in a more favorable response. In other words, would exposure to the curriculum result in either a reduced percentage of students reporting that inadequate time was devoted to instruction in nutrition or an increased percentage of students reporting that appropriate time was devoted to instruction in nutrition? This component of the evaluation was essential for determining whether medical students could identify nutrition content as such, especially in the context of an integrated curriculum. These changes were then compared with the responses to similar questions on the AAMC questionnaire.
Statistical analysis
Three general questions were asked to evaluate the nutrition curriculum: 1) What was the net change in total hours of nutrition content? 2) Did performance on the OSCE nutrition items improve in relation to exposure to the nutrition curriculum? 3) Did the medical students' perception of nutrition education change in response to the integrated nutrition curriculum? To address the first question, the statistical analysis included a comparison of the total hours of nutrition-related curriculum content before and after implementation of the nutrition curriculum as well as course-specific comparisons of nutrition content at baseline and after curriculum implementation.
Performance on the OSCE was the second focus for outcome analysis. The question asked was, "Do students apply learned nutrition knowledge in a clinical setting?" We addressed this question by using the nutrition subscale of the OSCE. We first determined whether the nutrition OSCE scores were improving over time. A one-way ANOVA and orthogonal contrasts were conducted among the students of CL95, CL96, CL97, and CL98. If the ANOVA was significant, we then compared CL94 and CL95 with CL96, CL97, and CL98. We also determined if there was a difference between CL96 and CL97-CL98 or between CL96, CL97, and CL98. All statistical analysis for this research was conducted with use of SPSS 9.0 statistical software (SPSS Inc, Chicago).
The third research question asked was, "Do students perceive that adequate nutrition instruction is available over the course of their medical education?" We addressed this question by comparing the percentage of change in response to nutrition-specific curriculum questions from the AAMC graduation questionnaire by year, including responses from the 1994 (before curriculum), 1995, 1996, and 1997 (total exposure to nutrition curriculum) questionnaires.
RESULTS
Nutrition content
The nutrition content in the medical curriculum before and after the integrated nutrition curriculum was implemented is illustrated in Table 1. At the start of the integrated nutrition curriculum in 1992, there were 35 h of required nutrition instruction during the 4 y of medical education. From 1993 to 1997, 75 h of required nutrition instruction existed. In addition, evaluation of the nutrition content topics showed that initially 9 of the 40 nutrition topics recommended as essential were included in the curriculum in 1992 (1). By 1996, 37 of the essential 40 items and 20 additional topics were included in medical student instruction (Table 2). Courses with the most significant increases in nutrition content included social and behavioral sciences, biochemistry, and preparation for clinical medicine.
View this table:
TABLE 1.. Hours of nutrition curriculum content by course at baseline and after the development and implementation of the integrated nutrition curriculum at the University of Arizona College of Medicine
View this table:
TABLE 2.. Nutrition topics recommended to be included in a medical school curriculum1
OSCE nutrition scores
One-way ANOVA indicated that the mean nutrition OSCE scores were significantly different between the medical school classes (P < 0.001). The mean (±SEM) nutrition OSCE scores were significantly greater (P < 0.05) for CL96 (50.8 ± 0.8), CL97 (51.0 ± 0.9), and CL98 (50.6 ± 1.1) than for CL94 (41.7 ± 0.9) and CL95 (41.8 ± 0.8). The increase in the nutrition OSCE score occurred while the overall OSCE score remained stable (61–64%). OSCE nutrition scores were nearly identical for students regardless of sex, undergraduate nutrition education, or selection of primary care or non-primary-care residency.
Medical School Graduation Questionnaire
More than 90% of UA students and >84% of all US medical school students completed the AAMC graduation questionnaire between 1994 and 1997. In 1994, 68.4% of the UA students and 62.6% of the students from all other US medical schools reported that the time devoted to nutrition was inadequate (Table 3). In 1997 fewer UA students (11.5%) thought that the amount of nutrition instruction was inadequate compared with the national percentage (37.2%). After 3 consecutive years of the integrated nutrition education curriculum, the percentage of UA students who believed that they had received an appropriate amount of nutrition education (74.7%) was higher than the national percentage (60.3%). This change was a greater improvement than that for similar areas that students scored as part of the AAMC, including basic medical sciences, clinical sciences, health promotion and disease prevention, and primary care (Table 3). A slightly higher percentage of the class of 1997 (12.5%) than the class of 1994 (3.8%) thought that nutrition was taught in excess at the UA; there was no significant difference in this measure between 1994 and 1997 for students in all US medical schools.
View this table:
TABLE 3.. Percentage of graduating students who considered that they received an inadequate or an appropriate amount of education in selected topics from the University of Arizona (UA) and all other US medical schools (USA)1
DISCUSSION
Our evaluation of the nutrition education program indicated that the integrated curriculum was a successful and time-efficient model for inclusion of multidisciplinary information into undergraduate medical training. Students educated by this approach could apply their knowledge, giving them advanced clinical skills, and could identify integrated topics as specific to the multidisciplinary curriculum area. This process for integrating nutrition into the medical curriculum was so effective that this approach was also used to integrate cancer prevention education into the medical curriculum and is being strongly considered to integrate other topics, such as geriatrics and education about death and dying.
This approach to medical-nutrition education resulted in a significant increase in nutrition education as measured by total hours of nutrition content, performance on nutrition-specific items included in a comprehensive examination of clinical skills, and student-reported perception of the adequacy of nutrition education in their medical school program. The approach provided an opportunity to distribute nutrition throughout the curriculum and may be a viable option for medical schools that are unable to establish a nutrition course because of time, financial, or personnel limitations. This nutrition program introduced a clinical orientation to basic science course materials and provided repeated exposure to nutrition information that enhanced clinical integration. This approach allowed for the inclusion of a variety of nutrition topics as recommended by the ASCN and the AMSA (1).
Clear limitations to the integrated nutrition curriculum need to be considered when initiating this approach to nutrition instruction. First, each nutrition topic area must be integrated into current curriculum. Second, students may have difficulty separating nutrition knowledge from general course content. To reduce this possibility, a nutrition orientation was developed for the students. The orientation was given at the onset of medical school and explained the integrated approach to nutrition education. A logo was also developed and was attached to all the nutrition content integrated into courses. A final limitation to the integrated approach is the reliance on faculty interest. The faculty members are not mandated to include nutrition in the course objectives, nor are they required to teach nutrition. Fortunately, the faculty members of the UA supported the nutrition curriculum and we were able to include at least some nutrition educational objectives in every course. The vice president for Health Sciences at the UA COM has now designated a permanent part-time faculty position to coordinate the nutrition program.
Recent reports on the nutrition education of medical students indicate that an increasing number of medical schools are working toward the provision of focused nutrition content (4, 21). A recent report of the AMA Council on Medical Education (4) cited that medical schools on average spend 27 h over the course of a 4-y medical education to teach the biochemical basis of nutrition, nutrition assessment, and clinical dietetics (4). On the basis of the available research, the UA COM, even before the implementation of this program, supported the inclusion of nutrition, albeit limited in scope.
An important aspect of the evaluation was how students were able to use their knowledge and skills in a clinical setting as assessed by the OSCE. Earlier research showed the effectiveness of the OSCE in evaluating the translation of knowledge and skills gained during medical education to future clinical practice (17, 18). The percentage of patients that receive nutrition counseling within physician offices is increasing, and nutrition counseling was shown to be a component of medical care in as many as 60% of physicians' offices (22). However, the quality of this counseling is unknown and the quantity is rather limited. Nutrition counseling in physician offices is frequently reported to be <5 min per patient (23–25). No differences were reported in OSCE performance between students who selected primary care or non-primary-care residencies even though the literature suggests that primary care physicians are more skilled in nutrition (26, 27). The OSCE scores indicated that students were able to identify, probe, and follow-up on nutrition issues within the clinical time that was allowed for each patient station. The OSCE measured the students' ability to identify patients and medical conditions that would benefit from nutrition intervention for disease prevention and therapy and to make appropriate, clear, and concise nutrition prescriptions and referrals.
The OSCE scores were higher for students who were exposed to an expanded nutrition curriculum throughout their medical education than for students whose exposure was minimal during their basic science education. Thus, the inclusion of nutrition instruction relative to the provision of medical care in a clinical setting was essential to developing the nutrition knowledge and skills needed to perform well on this examination.
Results from the AAMC graduation questionnaires indicated that the percentage of students who reported receiving an inadequate amount of instruction in nutrition decreased between 1994 and 1997. Of interest, the demonstrated change in perception of nutrition instruction was not associated with reported changes in perception of the adequacy or inadequacy of other content areas of the medical curriculum, implying that the nutrition instruction did not have a negative effect on other areas of the medical curriculum.
One avenue that still needs to be taken to increase the amount and appropriateness of nutrition in medical schools is to have these topics take a prominent place on national board examinations. The testing of nutrition knowledge as part of the US Medical Licensing Examination remains focused on nutritional deficiencies and does not appropriately address current issues in preventive and clinical nutrition (28). Three areas of nutrition now warrant special attention on national boards: 1) chronic disease prevention and control, 2) nutrition for persons at high risk of chronic diseases, and 3) nutrition during pregnancy and lactation.
In conclusion, the nutrition curriculum at the UA focused on nutrition intervention for disease prevention and therapy. It provided students with the knowledge and skills needed to make appropriate, clear, and concise nutrition prescriptions and referrals. Our experience provides additional insight into the development of new approaches to nutrition instruction in medical education. Other medical-nutrition curricula have taken on several formats, but outcome data are limited in terms of our ability to determine which formats may be best for educating medical students and more exportable between schools of medicine. This study attempted to advance the area of medical education by measuring a set of outcomes in the context of the development and implementation of an integrated nutrition curriculum in medical school education.
ACKNOWLEDGMENTS
We thank C Michael Brooks, Maurice Shils, Sachiko St Jeor, and Johanna Dwyer, who provided valuable consultation in the evaluation of the nutrition curriculum, and James Dalen and Jay Smith at the University of Arizona College of Medicine for providing the necessary administrative support to develop the nutrition curriculum.
REFERENCES