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1.
OBJECTIVES: A recent review of problem-based learning's effect on knowledge and clinical skills updated findings reported in 1993. The author argues that effect sizes (ES) seen with PBL have not lived up to expectations (0.8-1.0) and the theoretical basis for PBL, contextual learning theory, is weak. The purposes of this study were to analyse what constitutes reasonable ES in terms of the impacts on individuals and published reports, and to elaborate upon various theories pertaining to PBL. DESIGN: Normal theory is used to demonstrate what various ESs would mean for individual change and a large meta-analysis of over 10 000 studies is referred to in identifying typical ESs. Additional theories bearing upon PBL are presented. RESULTS: Effect sizes of 0.8-1.0 would require some students to move from the bottom quartile to the top half of the class or more. The average ES reported in the literature was 0.50 and many commonly used and accepted medical procedures and therapies are based upon studies with ESs below 0.50. CONCLUSIONS: Effect sizes of 0.8-1.0 are an unreasonable expectation from PBL because, firstly, the degree of changes that would be required of individuals would be excessive, secondly, leading up to medical school, students are groomed and selected for success in a traditional curriculum, expecting them to do better in a PBL curriculum than a traditional curriculum is an unreasonable expectation, and, thirdly, the average study reported in the literature and many commonly used and accepted medical procedures and therapies are based upon studies having lesser ESs. Information-processing theory, Cooperative learning, Self-determination theory and Control theory are suggested as providing better theoretical support for PBL than Contextual learning theory. Even if knowledge acquisition and clinical skills are not improved by PBL, the enhanced work environment for students and faculty that has been consistently found with PBL is a worthwhile goal.  相似文献
2.
国外医疗救助政策比较   总被引:6,自引:0,他引:6  
通过分析国家医疗保险、社会医疗保险、商业医疗保险、储蓄医疗保险四种筹资体系下英国、德国、美国、新加坡四个发达国家医疗救助的具体政策,总结出各国医疗救助政策在强调政府责任、聚焦弱势人群、定位低层次、严格管理程序等政策制定、执行上的共同特点,以期为我国医疗救助的更好开展提供借鉴。  相似文献
3.
Prevalence and Trends in Overweight in Mexican-American Adults and Children   总被引:4,自引:0,他引:4  
Overweight and obesity have been increasing in many countries. Our objective is to describe the trends in overweight and obesity occurring in the Mexican-American population in the United States. Data on measured height and weight for Mexican Americans come from the following surveys: the Hispanic Health and Nutrition Examination Survey (HHANES, 1982–84), the Third National Health and Nutrition Examination Survey (NHANES III, 1988–94), and NHANES 1999–2002. In 1999–2002, 73% of Mexican-American adults were overweight and 33% were obese. Obesity increased between NHANES III and NHANES 1999–2002, from 24% to 27% for men and from 35% to 38% for women. Increases were also seen for children and adolescents. The Mexican-American population in the United States, both children and adults, is showing trends in overweight and obesity over time that are similar to those seen in other segments of the U.S. population and indeed in many countries  相似文献
4.
美国卫生费用持续上涨的原因及控制措施   总被引:4,自引:0,他引:4  
目前美国的卫生费用基数庞大,1998年占GDP的14%,造成卫生经费持续上涨的原因除通货膨胀外,还与以下因素有关;第三方付费的方式、不完善的市场、新技术的应用、人口老龄化,卫生保健模式、多方付费系统,庞大的管理费用、防卫性医疗、浪费等,在美国控制医疗费用的措施包括政府行为和市场竞争机制两方面,比如;资源配置许可制度、对外国医科毕业生的限制政策、采用DRG付费方式、管理型保健医疗等。  相似文献
5.
Despite a lack of face validity, there continues to be heavy reliance on objective paper-and-pencil measures of clinical competence. Among these measures, the most common item formats are patient management problems (PMPs) and three types of multiple choice questions (MCQs): one-best-answer (A-types); matching questions (M-types); and multiple true/false questions (X-types). The purpose of this study is to compare the reliability, validity and efficiency of these item formats with particular focus on whether MCQs and PMPs measure different aspects of clinical competence. Analyses revealed reliabilities of 0.72 or better for all item formats; the MCQ formats were most reliable. Similarly, efficiency analyses (reliability per unit of testing time) demonstrated the superiority of MCQs. Evidence for validity obtained through correlations of both programme directors' ratings and criterion group membership with item format scores also favoured MCQs. More important, however, is whether MCQs and PMPs measure the same or different aspects of clinical competence. Regression analyses of the scores on the validity measures (programme directors' ratings and criterion group membership) indicated that MCQs and PMPs seem to be measuring predominantly the same thing. MCQs contribute a small unique variance component over and above PMPs, while PMPs make the smallest unique contribution. As a whole, these results indicate that MCQs are more efficient, reliable and valid than PMPs.  相似文献
6.
INTRODUCTION: The results of the United States Medical Licensing Examination Step 1 and 2 examinations are reported for students enrolled in a problem-based and traditional lecture-based curricula over a seven-year period at a single institution. There were no statistically significant differences in mean scores on either examination over the seven year period as a whole. There were statistically significant main effects noted by cohort year and curricular track for both the Step 1 and 2 examinations. These results support the general, long-term effectiveness of problem-based learning with respect to basic and clinical science knowledge acquisition. CONTEXT: This paper reports the United States Medical Licensing Examination Step 1 and Step 2 results for students enrolled in a problem-based and traditional lecture-based learning curricula over the seven-year period (1992-98) in order to evaluate the adequacy of each curriculum in supporting students learning of the basic and clinical sciences. METHODS: Six hundred and eighty-nine students who took the United States Medical Licensing Examination Step 1 and 540 students who took Step 2 for the first time over the seven-year period were included in the analyses. T-test analyses were utilized to compare students' Step 1 and Step 2 performance by curriculum groups. RESULTS: United States Medical Licensing Examination Step 1 scores over the seven-year period were 214 for Traditional Curriculum students and 208 for Parallel Curriculum students (t-value = 1.32, P=0.21). Mean Step 2 scores over the seven-year period were 208 for Traditional Curriculum students and 206 for Parallel Curriculum students (t-value=1.08, P=0.30). Statistically significant main effects were noted by cohort year and curricular track for both the Step 1 and Step 2 examinations. CONCLUSION: The totality of experience in both groups, although differing by curricular type, may be similar enough that the comparable scores are what should be expected. These results should be reassuring to curricular planners and faculty that problem-based learning can provide students with the knowledge needed for the subsequent phases of their medical education.  相似文献
7.
AIMS: Obesity and physical inactivity are known to be risk factors for many chronic diseases including hypertension, coronary artery disease, diabetes, and cancer. We sought to explore the association between an indicator of transportation data (Vehicle Miles of Travel, VMT) at the county level as it relates to obesity and physical inactivity in California. METHODS: Data from the California Health Interview Survey 2001 (CHIS 2001), the US 2000 Census, and the California Department of Transportation were merged to examine ecological correlations between vehicle miles of travel, population density, commute time, and county indicators of obesity and physical inactivity. Obesity was measured by body mass index (BMI). Physical inactivity was based on self-reported behaviors including walking, bicycling, and moderate to vigorous activity. The unit of analysis was the county. Thirty-three counties in California with population size greater than 100,000 persons per county were retained in the analyses. RESULTS: CHIS 2001 statewide obesity prevalence ranged from 11.2% to 28.5% by county. Physical inactivity ranged from 13.4% to 35.7%. Daily vehicle miles of travel ranged from 3.3 million to 183.8 million per county. By rank bivariate correlation, obesity and physical inactivity were significantly associated (p<0.01). Furthermore, by rank analysis of variance, the highest mean rank obesity was associated with the highest rank of VMT (p<0.01). Similar rank patterns were observed between obesity and physical inactivity and commute time. Associations between VMT and physical inactivity were examined but failed to reach statistical significance. CONCLUSION: This analysis adds to the growing evidence supporting the association between VMT (a measure of automobile transportation) and obesity. An urban design characterized by over dependence on motorized transportation may be related to adverse health effects.  相似文献
8.
Evidence-based medicine is the application of scientific evidence to clinical practice. This article discusses the difficulties of applying global evidence ("average effects" measured as population means) to local problems (individual patients or groups who might depart from the population average). It argues that the benefit or harm of most treatments in clinical trials can be misleading and fail to reveal the potentially complex mixture of substantial benefits for some, little benefit for many, and harm for a few. Heterogeneity of treatment effects reflects patient diversity in risk of disease, responsiveness to treatment, vulnerability to adverse effects, and utility for different outcomes. Recognizing these factors, researchers can design studies that better characterize who will benefit from medical treatments, and clinicians and policymakers can make better use of the results.  相似文献
9.
The health of the California region bordering Mexico   总被引:3,自引:0,他引:3  
Healthy Border (HB) 2010 is the health promotion and disease prevention agenda through the year 2010 of the United States-Mexico Border Health Commission (BHC). On the United States side, it draws from the Healthy People (HP) 2010 objectives, identifying those most important and relevant for the border. The BHC has harmonized the list of objectives from both countries into a set of 19 that will be monitored and addressed in a collaborative manner. HB provides a framework for describing the border region's health and comparing with others. For this report, available data were collected for the HB indicators for San Diego and Imperial counties, and for California. Data on Latino populations were considered a proxy for Mexican-Americans and people of Mexican origin in California, because more specific data are not available. Results are presented on the 14 indicators for which the data were most complete. Those of most concern include access to health care and tuberculosis in both counties, plus motor vehicle crash injury deaths and asthma hospitalizations in Imperial. These issues should be given priority attention. Conversely, the region's and Latinos' experience with breast cancer mortality and infant mortality is favorable. Recommendations include binational collaborations in assessing and improving the health of our border communities.  相似文献
10.
美国电子健康档案发展策略及启示   总被引:3,自引:0,他引:3  
美国是电子健康档案建设的先行者,经过40余年的发展,取得了显著进展,并在电子健康档案的组织建设、标准制定、资金筹集、隐私与安全保护、利益相关者协调方面积累了丰富的经验。主要论述了美国电子健康档案的发展历程及具体策略,以期为我国电子健康档案建设提供借鉴。  相似文献
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