Difference In Mean Rank Research Articles

Study skills and strategies of the medical students among medical colleges in Mysore district, Karnataka, India

Background: Study skills are discrete techniques that can be learned, usually in a short time, and applied to all or most fields of study. The approach students choose appears to be a central factor in determining both the quality and quantity of their learning. Learning styles influence the maintenance of information and the depth of understanding. Methods: A prospective interventional study was conducted among the medical students of phase-II, phase-III part-I and part II studying in government and private medical colleges. The data regarding socio-demographic characteristics like age, sex, religion, total family income, locality, phase of MBBS Course, state in India from which the student came and the learning skills were collected on a self-administered pre tested structured questionnaire, which will also include Study Skills Inventory tool. Paired t test for academic performance before and after intervention, Mann Whitney test for difference in mean ranks in study skill scores between Government and private colleges, spearman correlation for academic skills and study skill scores were applied. Results: The note-taking skills, memory skills and time management skills of private medical college students and their academic performance were correlated significantly. There was a significant improvement in the academic performance of private medical college students by 3.01 and government medical college students by 3.69 after the intervention. Conclusions: There was a significant improvement in the academic performance of both private and government medical college students after the intervention.

Effect of Cobb angle and BMI on scoliosis surgery recovery in adolescent idiopathic scoliosis patients

Aims and Objectives: To assess the effect of Cobb angle and body mass index (BMI) on surgery recovery outcomes in Adolescent Idiopathic Scoliosis (AIS) patients.Materials and Methods: A retrospective study of 79 Adolescent Idiopathic Scoliosis patients who underwent corrective operations, at King Khaled University Hospital, Riyadh, Saudi Arabia was carried out in 2014. The patients were divided according into Cobb’s angle (mild, moderate and severe) and as per weight (healthy weight and overweight). Data of preoperative, intra-operative and postoperative information as well as measures of daily-living activities were collected.Results: The mean age of 79 patients (70females) was 16.6 years. Cobb angle assessment was mild in 41 (51.9%), moderate in 24(30.4%) and 14(17.7%) were severe. Mean surgery and recovery time of patients is statistically significantly different in relation to severity of Cobb’s angle (mild, moderate and severe). There is highly statistically significant difference in mean ranks of days taken for different measures of daily living in relation to severity of Cobb’s angle. The mean values of body mass index have significantly reduced after surgery, when compared with mean values at before surgery. The mean surgery time was statistically significantly higher in over weight patients (5.33 hours).Conclusions: The results show an effect of severity of Cobb angle on recovery measures of patients with AIS, but no effect of BMI. BMI was corrected in these patients after surgery. Prospective studies are required to assess clinical outcomes of post-operative surgery, satisfaction of patients towards their body image and quality of life.Asian Journal of Medical Sciences Vol.7(2) 2015 28-33

Nosocomial hepatitis C virus transmission from tampering with injectable anesthetic opioids.

The extent of provider-to-patient hepatitis C virus (HCV) transmission from diversion, self-injection, and substitution ("tampering") of anesthetic opioids is unknown. To quantify the contribution of opioid tampering to nosocomial HCV outbreaks, data from health care-related HCV outbreaks occurring in developed countries from 1990 to 2012 were collated, grouped, and compared. Tampering was associated with 17% (8 of 46) of outbreaks, but 53% (438 of 833) of cases. Of the tampering outbreaks, six (75%) involved fentanyl, five (63%) occurred in the United States, and one each in Australia, Israel, and Spain. Case counts ranged from 5 to 275 in the tampering outbreaks (mean, 54.8; median, 25), and 1-99 in the nontampering outbreaks (mean, 10.4; median, 5); between them, the difference in mean ranks of counts was significant (P < 0.01). To estimate HCV transmission risks from tampering, risk-assessment models were constructed, and these risks compared with those from surgery. HCV transmission risk from exposure to an opioid preparation tampered by a provider of unknown HCV infection status who is a person who injects drugs (PWID; 0.62%; standard error [SE] = 0.38%) exceeds 16,757 times the risk from surgery by a surgeon of unknown HCV infection status (0.000037%; SE = 0.000029%) and 135 times by an HCV-infected surgeon (0.0046%; SE = 0.0033%). To pose a 50% patient transmission risk, an infected surgeon may take 30 years, compared to <1 year for a PWID tamperer, and weeks or days for a PWID tamperer who intensifies access to opioids. Disproportionately, many cases of HCV infection from nosocomial outbreaks were attributable to provider tampering of anesthetic opioids. Transmission risk from tampering is substantially higher than from surgery.

Hands-free image capture, data tagging and transfer using Google Glass: a pilot study for improved wound care management.

Chronic wounds, including pressure ulcers, compromise the health of 6.5 million Americans and pose an annual estimated burden of $25 billion to the U.S. health care system. When treating chronic wounds, clinicians must use meticulous documentation to determine wound severity and to monitor healing progress over time. Yet, current wound documentation practices using digital photography are often cumbersome and labor intensive. The process of transferring photos into Electronic Medical Records (EMRs) requires many steps and can take several days. Newer smartphone and tablet-based solutions, such as Epic Haiku, have reduced EMR upload time. However, issues still exist involving patient positioning, image-capture technique, and patient identification. In this paper, we present the development and assessment of the SnapCap System for chronic wound photography. Through leveraging the sensor capabilities of Google Glass, SnapCap enables hands-free digital image capture, and the tagging and transfer of images to a patient’s EMR. In a pilot study with wound care nurses at Stanford Hospital (n=16), we (i) examined feature preferences for hands-free digital image capture and documentation, and (ii) compared SnapCap to the state of the art in digital wound care photography, the Epic Haiku application. We used the Wilcoxon Signed-ranks test to evaluate differences in mean ranks between preference options. Preferred hands-free navigation features include barcode scanning for patient identification, Z(15) = -3.873, p < 0.001, r = 0.71, and double-blinking to take photographs, Z(13) = -3.606, p < 0.001, r = 0.71. In the comparison between SnapCap and Epic Haiku, the SnapCap System was preferred for sterile image-capture technique, Z(16) = -3.873, p < 0.001, r = 0.68. Responses were divided with respect to image quality and overall ease of use. The study’s results have contributed to the future implementation of new features aimed at enhancing mobile hands-free digital photography for chronic wound care.

Construct validity of the Simbionix bronch mentor simulator for essential bronchoscopic skills.

Although simulation-based bronchoscopy has been shown to be an effective training modality, formal assessment should still be performed as new technology emerges. We sought to validate a simulator in essential bronchoscopic tasks, and survey perceptions of bronchoscopists on simulation. A cohort study at 2 medical centers used 3 groups to assess construct validity of the Simbionix Bronchoscopy Simulator: 7 first-year fellows with <10 bronchoscopies each (novice), 6 pulmonologists with 200 to 1000 bronchoscopies each (experienced), and 7 pulmonologists with >1000 bronchoscopies each (expert). Participants were tested in 4 tasks (1: scope manipulation, 2: guided anatomic navigation, 3: airway anatomy, and 4: lymph node anatomy). Participants were scored and surveyed on their impressions of simulation. The means and Kruskal-Wallis test among groups were compared by task item (P<0.05). There were statistically significant differences in mean ranks among groups for tasks 1 and 3. For task 1, final score, time, mid-lumen time, and wall hits were discriminative (P=0.006, 0.006, 0.012, and 0.014, respectively). For task 3, time, bronchial segments identified, bronchial segments incorrectly identified, and bronchial segments skipped were discriminative (P=0.04, 0.012, 0.013, and 0.013, respectively). There was no statistically significant difference for task 2 and task 4. All participants agreed that simulation training is helpful and should be incorporated into bronchoscopic training. The simulator demonstrated validity in differentiating skill in scope manipulation and airway anatomy, but did not discriminate skill levels in anatomic orientation or identification of lymph nodes. Bronchoscopy simulation was viewed as helpful by all levels and should be considered before performance on patients.

Comparison of Paper- and Web-Based Dietary Records: A Pilot Study

Background/Aims: Paper-based dietary records (Paper-DR) can be replaced by web-based dietary records (Web-DR) in both epidemiological studies and clinical practice to reduce the time and logistic burden. We aimed to compare Paper-DR and Web-DR. Methods: We compared the matching of different food items (n = 1,103) from Paper-DR and Web-DR for energy and 48 nutrients among 16 pregnant volunteers, with DR for the same individuals matched for the same 4 days. Paper-DR were coded into the web-based version (referred to as Paper-Web-DR) independently by the same research dietitian. The Wilcoxon signed-rank test comparing mean rank differences, Spearman's ρ to measure associations and Bland-Altman limits of agreement to evaluate the level of agreement between the two dietary methods across the range of parameters were used. Volunteers also completed an evaluation questionnaire regarding the user acceptability of Paper-DR and Web-DR. Results: A high correlation between Paper-DR and Web-DR was noted. There were statistically insignificant differences among 45 nutrients, except for free sugars (p < 0.001), α-linolenic acid (p = 0.041), folate (p = 0.036) and pantothenic acid (p = 0.023). Volunteers found the Paper-DR equally time-consuming as the Web-DR. The majority of the volunteers (75%) preferred the Web-DR. Conclusions: Paper-DR and Web-DR were comparable across a range of nutritional parameters, with a few exceptions. The Web-DR was more convenient for the majority and has substantial logistic and cost advantages.

Marital Status, Religiosity, And Experience As A Predictor Of Ethical Awareness Among Accounting Professionals

Many corporations and their accountants have taken ethics for granted. This oversight has led to the closing of companies such as Enron and WorldCom. Accountants are placed in positions of having to render ethical decisions daily, and when they lose sight of ethical values, the dissolution of corporations can occur. The goal in this quantitative research is to investigate the relationship between the independent variables of marital status, religiosity, and years of work experience and the dependent variable of ethical decision-making. Eighty-three members of the Michigan Association of Certified Public Accountants (MACPA) completed an internet-delivered survey on ethical dilemmas. Because they were contacted through the MACPA weekly E-newsletter, the respondents were those members who chose to accept the weekly electronic newsletter and who read it. The 83 participant responses were saved within Survey Monkey and extracted by the authors. A nonparametric Kruskal-Wallis test examined differences in mean rank order of ethical decision-making scores among the marital status groupings and revealed no significant differences in mean ranks (?2 (4, N=83) = 3.810, p = .432) or among the years of work experience (?2 (5, N = 83) = 7.768, p = .170). Based on results of the tests, the hypothesis that there is no relationship between ethical decision-making and marital status and between ethical decision-making and years of work experience cannot be rejected. A Spearman correlation analysis revealed no significant association (rho = -0.084, p = 0.226, n = 83) between ethical decision-making and religiosity. Based on the results of these and related tests, the hypothesis that there is no relationship between ethical decision-making and religiosity could not be rejected. The results from this study have added to the limited literature on ethical decision-making and three variables of marital status, religiosity, and years of work experience. The authors recommendation for future research is to conduct studies within different professional organizations and with additional variables including gender, sexual orientation, age, and self-assessments. Also, given the small response size of this study, a larger, more representative sample size would give the study more credibility.

Construct Validity of the Simbionix Bronch Mentor Simulator for Essential Bronchoscopic Skills

BACKGROUND Although simulation-based bronchoscopy has been shown to be an effective training modality, formal assessment should still be performed as new technology emerges. We sought to validate a simulator in essential bronchoscopic tasks, and survey perceptions of bronchoscopists on simulation. METHODS A cohort study at 2 medical centers used 3 groups to assess construct validity of the Simbionix Bronchoscopy Simulator: 7 first-year fellows with 1000 bronchoscopies each (expert). Participants were tested in 4 tasks (1: scope manipulation, 2: guided anatomic navigation, 3: airway anatomy, and 4: lymph node anatomy). Participants were scored and surveyed on their impressions of simulation. The means and Kruskal-Wallis test among groups were compared by task item (P<0.05). RESULTS There were statistically significant differences in mean ranks among groups for tasks 1 and 3. For task 1, final score, time, mid-lumen time, and wall hits were discriminative (P=0.006, 0.006, 0.012, and 0.014, respectively). For task 3, time, bronchial segments identified, bronchial segments incorrectly identified, and bronchial segments skipped were discriminative (P=0.04, 0.012, 0.013, and 0.013, respectively). There was no statistically significant difference for task 2 and task 4. All participants agreed that simulation training is helpful and should be incorporated into bronchoscopic training. CONCLUSIONS The simulator demonstrated validity in differentiating skill in scope manipulation and airway anatomy, but did not discriminate skill levels in anatomic orientation or identification of lymph nodes. Bronchoscopy simulation was viewed as helpful by all levels and should be considered before performance on patients.

Prolonged Survival of E.Coli but Not Staphylococcus Aureus in Monocytes From Patients With Crohn's Disease

Introduction A primary macrophage defect has been proposed to play a role in Crohn9s disease (CD) pathogenesis.1 In CD, Escherichia coli persist within lamina propria macrophages and peripheral blood monocytes are unable to effectively kill E coli in vitro.23 It is uncertain whether this abnormal bacterial handling by monocytes and macrophages in CD is limited to certain strains of E coli or whether a broader bacterial killing defect exists. The aim of this study was to compare intracellular survival of E coli with Staphylococcus aureus (not a usual resident of gut flora) within CD-derived and control monocytes. Methods Peripheral blood was taken from eight healthy controls and nine CD patients. CD distribution was ileal (n=1) and ileocolonic (n=8). Three CD patients were on thiopurines. Monocyte isolation was performed by iodixanol barrier flotation. Monocytes were challenged with a CD-derived strain of E coli and methicillin sensitive Staphylococcus aureus (MSSA). After 1 h incubation, the gentamicin protection assay was performed. Monocytes were lysed to release internalized bacteria after further incubation for 1 and 4 h. Cell lysates were plated on agar and incubated for 24 h at 37°C. Colony forming units (CFU) were counted after both 1 and 4h incubation. The CFU counts at these time points allowed relative replication to be determined. Results Viable CD-derived E coli were cultured from cell lysates at 1 and 4 h from 9/9 CD patients, and in 3/8 HC9s (mean increase CFUs from 1 to 4 h: CD +394%, HC −7%). Viable S aureus was cultured in cell lysates at 1 and 4 h respectively from 1/9 and 0/9 CD patients and 0/8 healthy controls at both time points. The difference in the number of CFU9s present for each subject at 1 and 4 h was calculated and there was a statistically significant difference in mean rank of (CFU (4 h) – CFU (1 h)) between CD and HC9s for E coli but not for staph aureus (Mann–Whitney U test). Conclusion Within CD-derived peripheral monocytes, intracellular survival is prolonged for E coli but not for S aureus , illustrating that impairment of killing by monocytes in CD is restricted to particular bacteria. This is consistent with the clinical observation that CD primarily affects the gut which has an extensive but specific microbiome, rather than causing systemic immunodeficiency characterised by infections in other systems.

Aspirations and wellbeing in Romanian and US undergraduates

Updating cross-cultural research of the past decade on the relationship between life aspirations and wellbeing, we compared Romanian (N=69) and US (N=64) undergraduates on the contribution of the importance and likelihood of attaining intrinsic and extrinsic aspirations to psychological maladjustment and life satisfaction, and on the qualitative meaning they assign to financial success. Similarly to prior studies, we found that extrinsic and intrinsic aspirations tended to be either negatively or positively correlated with life satisfaction, respectively; however, wealth predicted life satisfaction for Romanian students. Unlike previous research, we found generally negative relationships between intrinsic aspirations and psychological maladjustment. Although there were no differences between Romanian and US undergraduates on extrinsic and intrinsic orientation, on the overall importance of attaining aspirations, or on specific extrinsic and intrinsic aspirations, Romanian students expressed weaker expectations of fulfilling intrinsic aspirations than did US students. Finally, the groups produced similar rankings of aspirations and assigned similar meaning to financial success. The results favored a social cognitive rather than a self-determination model of psychological wellbeing in that expectations for attaining aspirations were more often predictive of life satisfaction than were their content. We interpret these findings and their convergence and departure from earlier research in terms of political economic, demographic, and cultural factors. We encourage future cross-cultural investigations of the social construction of aspirations, subsidiation of seemingly contradictory aspirations to each other, and cognitive and ecological mediation of the complex relationship of aspirations to psychological functioning.

Prolonged survival of E coli but not Staphylococcus aureus in monocytes from patients with Crohn's disease

IntroductionA primary macrophage defect has been proposed to play a role in Crohn's disease (CD) pathogenesis.1 In CD, Escherichia coli persist within lamina propria macrophages and peripheral blood monocytes are...

Use of Ordinal Outcomes in Vascular Prevention Trials

Background and Purpose— Vascular prevention trials mostly count “yes/no” (binary) outcome events, eg, stroke/no stroke. Analysis of ordered categorical vascular events (eg, fatal stroke/nonfatal stroke/no stroke) is clinically relevant and could be more powerful statistically. Although this is not a novel idea in the statistical community, ordinal outcomes have not been applied to stroke prevention trials in the past. Methods— Summary data on stroke, myocardial infarction, combined vascular events, and bleeding were obtained by treatment group from published vascular prevention trials. Data were analyzed using 10 statistical approaches which allow comparison of 2 ordinal or binary treatment groups. The results for each statistical test for each trial were then compared using Friedman 2-way analysis of variance with multiple comparison procedures. Results— Across 85 trials (335 305 subjects) the test results differed substantially so that approaches which used the ordinal nature of stroke events (fatal/nonfatal/no stroke) were more efficient than those which combined the data to form 2 groups ( P &lt;0.0001). The most efficient tests were bootstrapping the difference in mean rank, Mann–Whitney U test, and ordinal logistic regression; 4- and 5-level data were more efficient still. Similar findings were obtained for myocardial infarction, combined vascular outcomes, and bleeding. The findings were consistent across different types, designs and sizes of trial, and for the different types of intervention. Conclusions— When analyzing vascular events from prevention trials, statistical tests which use ordered categorical data are more efficient and are more likely to yield reliable results than binary tests. This approach gives additional information on treatment effects by severity of event and will allow trials to be smaller.

Genetic variation in arctic populations of timothy (Phleum pratense L.): II. Phenotypic stability of seed production

Rognli, O.A. 1987. Genetic variation in arctic populations of timothy (Phleum pratense L.). II. Phenotypic stability of seed production. —Hereditas 207: 75–94. Lund, Sweden. ISSN 0018–0661. Received November 10, 1986 The present paper is concerned with phenotypic stability of seed production of four North Norwegian timothy populations. In clonal experiments conducted at 69°N. 63.S°N, and 60°N latitude in Norway. the genotype × location interaction was the most important interaction effect. Individual genotypic stability reactions were studied by ecovalence (or stability variance), and mean rank difference. Pattern analysis was used to investigate the form of the individual genotypic reactions. Large differences in stability were found among genotypes. Only 11.5% of the genotypes contributed significantly to the interaction sum of squares. Elimination of very unstable genotypes could therefore be a strategy of population improvement. rather than selecting stable genotypes. Correlation between ecovalence and mean rank difference depended upon the yield level, being low for high yielding genotypes. Ecovalence and average seed yield were positively correlated, but high yielding and stable genotypes could be found. Stability rankings were sufficiently consistent over years to justify a single year test of stability. Pattern analysis (FASTCLUS) was performed on the individual genotypic within-location residuals. Structure of cluster groups revealed specific genotypic and population adaptations, assessed according to the ecovalence concept. Canonical discriminant analysis (CANDISC) was used to aid visual interpretation of group differences.

The Role of Parental Consent in Adolescent Substance Use Research

Purpose The objective of our study was to assess the effects of requiring parental consent upon study participation and self-reported substance-related problems among 14–18-year-olds. Methods This was a secondary analysis of combined data from two similar studies of adolescent substance use that recruited participants from the same adolescent clinic at Children’s Hospital Boston. Study 1 waived parental consent, whereas Study 2 required parental consent. The combined dataset included demographic characteristics and Car, Relax, Alone, Forget, Friends, Trouble (CRAFFT) study screening test responses. The CRAFFT is an orally administered screen that yields a score from 0–6 and that has been shown to be a valid and reliable measure of risk for substance-related problems. Results The participation refusal rate in Study 1, where consent was waived, was 19.7% (132 of 670 eligible individuals) and in Study 2 (243 of 411 eligible individuals), where consent was required, it was 59.1% ( p < .0001). Participants did not differ significantly with respect to gender and age but did differ by self-identified race/ethnicity between the two studies. Because the CRAFFT score distributions were highly skewed, we used the nonparametric Mann-Whitney U test for differences in mean rank. The mean rank in Study 1 was significantly higher than in Study 2 (mean rank 362 vs. 325, p = .02). After controlling for age, gender, and race/ethnicity, the adjusted proportional odds ratio for a one-point increase in CRAFFT score was 1.47 (CI 1.03, 2.10) for Study 1 compared with Study 2. Conclusions The research requirement of parental consent may result in substantial self-selection bias towards a lower risk sample.

Can We Improve the Statistical Analysis of Stroke Trials?

Most large acute stroke trials have been neutral. Functional outcome is usually analyzed using a yes or no answer, eg, death or dependency versus independence. We assessed which statistical approaches are most efficient in analyzing outcomes from stroke trials. Individual patient data from acute, rehabilitation and stroke unit trials studying the effects of interventions which alter functional outcome were assessed. Outcomes included modified Rankin Scale, Barthel Index, and "3 questions". Data were analyzed using a variety of approaches which compare 2 treatment groups. The results for each statistical test for each trial were then compared. Data from 55 datasets were obtained (47 trials, 54,173 patients). The test results differed substantially so that approaches which use the ordered nature of functional outcome data (ordinal logistic regression, t test, robust ranks test, bootstrapping the difference in mean rank) were more efficient statistically than those which collapse the data into 2 groups (chi(2); ANOVA, P<0.001). The findings were consistent across different types and sizes of trial and for the different measures of functional outcome. When analyzing functional outcome from stroke trials, statistical tests which use the original ordered data are more efficient and more likely to yield reliable results. Suitable approaches included ordinal logistic regression, t test, and robust ranks test.

Tests for balanced incomplete block ranked data with ties

We consider balanced incomplete block data when ties occur and propose new statistics for testing (a) differences in mean ranks, (b) differences in distributions of ranks, (c) differences in nonlinear effects of ranks and (d) linear contrasts. A sensory evaluation example where the data are ranks is given.

The Impact of Silhouette Randomization on the Results of Figure Rating Scales

This study was designed to examine the impact of silhouette randomization on the responses to rating scales developed to rate the perceived current and ideal body shape, as well as body dissatisfaction. Seventy students (30 men and 40 women), ages 18 to 43 (M ± SD = 22.1 ± 5.7) years, completed the Stunkard, Sorensen, and Schulsinger (1983) Figure Rating Scale twice, approximately 2 weeks apart in a randomized, counterbalanced order. On one occasion, the traditional scale was completed, and another scale with a randomized set of silhouettes was completed. Results indicated a significant relationship between the traditionally and randomly presented scales for perceived current and ideal body shapes and for body dissatisfaction (all p < .01). Wilcoxon signed-ranks test revealed no significant mean rank difference between the two scales for perceived current and ideal body shapes and body dissatisfaction (all p > .05). Randomization of figures does not appear to have an impact on results from the Figure Rating Scale, and the sequentially presented scale appears to be appropriate for body image assessment.

Medical Students' Motivations to Volunteer: An Examination of the Nature of Gender Differences

A sample of medical students was surveyed using the Volunteer Functions Inventory, an instrument that assesses the importance of 6 possible motives to volunteer that range from altruistic and humanitarian concern for others to more self-interested, career-related motives. Researchers in the past have described mean differences and rank differences for gender. Profile analysis was conducted to assess the relative importance of each motive by gender. Women rated all motives higher than did men. The relative ranking of the importance of the motives was similar for both genders. Contrary to previous studies, women rated instrumental motives at least as high as did men. Both genders rated altruistic motives highly. The results of this study may be used to inform a training curriculum or advertising campaign aimed at increasing volunteer efforts.

Foliar resistance to late blight in potato clones evaluated in national trials in 1997

Changes in the oomycetePhytophthora infestans in the United States and other parts of the world pose a significant threat to potato production. A continual evaluation of potato clones for resistance to late blight is necessary to identify clones with resistance and to monitor the stability of resistance in light of the emergence of new and more aggressive strains of this pathogen. Twentytwo potato clones (10 cultivars and 12 selections) were evaluated in 1997 for late blight resistance at seven U.S. locations. Seven late blight differentials (R1R2R3R4, R1R2R4, R1R3R4 R3, R8 R10, and Rmulti) were also included in the test at five of these locations. The US-8 strain of P.infestans was present at all locations. Percent infected foliage was recorded at approximately weekly intervals following the onset of disease. Area under the disease progress curve (AUDPC) was calculated. The nonparametric stability statistics mean absolute rank differences (Si(1)) and variances of the ranks (Si(2)) were used to analyze phenotypic stability. Although neither of these statistics was significant for individual clones, both of these statistics were significant when summed over clones, indicating the importance of genotype × environment interactions on the rankings of these clones across locations. The most late blight-resistant and susceptible clones were the most stable; clones in the intermediate ranges were most subject to rank changes due to genotype × environment interactions. The most late blight-resistant clones were AWN86514-2, B0692-4, B0718-3, and B0767-2. The most susceptible clones were B0811-13, B1004-8, Nor-Donna, and Krantz. AUDPC was very low for the late blight differentials R8 and Rmulti, moderately low for R10 and very high for the remaining differentials. This study is important in characterizing the reaction of potato clones to new strains of P.infestans.

Does clinical exposure affect medical student examination performance?

Background: Traditionally important components of the surgical clerkship curriculum include lectures, small-group sessions, readings, clinical exposure, and testing. Time constraints require compromise among all these elements. At our institution, clinical exposure of medical students varies according to their team assignments. They differ primarily in exposure to such topics as trauma, inflammatory bowel disease (IBD), and vascular surgery. Purpose: The goal of this study was to quantify the influence of clinical exposure on medical student education, testing whether it influences examination performance. Methods: At the beginning of the clerkship, students were given a written multiple-choice examination covering these three topics. They completed two 4-week blocks on surgery services in various settings. At the end of the clerkship, they were reexamined. Differences between pretest and posttest overall mean rank were analyzed using the Wilcoxon signed ranks test. Differences in improvement based on clinical exposure were analyzed using the Mann-Whitney U test. Results: Statistically significant improvement was seen in overall examination performance, as well as in each of the subsections. However, these improvements could not be accounted for by clinical exposure. There was no statistically significant difference in mean rank in improvement based on clinical exposure to vascular, IBD, or trauma. Conclusions: Student examination scores improved over the course of the clerkship. No improvement could be attributed to greater clinical exposure to a topic.