Protocol of the Luebeck longitudinal investigation of SARS-CoV-2 infection (ELISA) study - a prospective population-based cohort study.

BACKGROUND: Considering the insufficiently controlled spread of new SARS-CoV-2 variants, partially low vaccination rates, and increased risk of a post-COVID syndrome, well-functioning, targeted intervention measures at local and national levels are urgently needed to contain the SARS-CoV-2 pandemic. Surveillance concepts (cross-sectional, cohorts, clusters) need to be carefully selected to monitor and assess incidence and prevalence at the population level. A critical methodological gap for identifying specific risks/dynamics for SARS-Cov-2 transmission and post-COVID-19-syndrome includes repetitive testing for past or present infection of a defined cohort with simultaneous assessment of symptoms, behavior, risk, and protective factors, as well as quality of life. METHODS: The ELISA-Study is a longitudinal, prospective surveillance study with a cohort approach launched in Luebeck in April 2020. The first part comprised regular PCR testing, antibody measurements, and a recurrent App-based questionnaire for a population-based cohort of 3000 inhabitants of Luebeck. The follow-up study protocol includes self-testing for antibodies and PCR testing for a subset of the participants, focusing on studying immunity after vaccination and/or infection and post-COVID-19 symptoms. DISCUSSION: The ELISA cohort and our follow-up study protocol will enable us to study the effects of a sharp increase of SARS-CoV-2 infections on seroprevalence of Anti-SARS-CoV-2 antibodies, post-COVID-19-symptoms, and possible medical, occupational, and behavioral risk factors. We will be able to monitor the pandemic continuously and discover potential sequelae of an infection long-term. Further examinations can be readily set up on an ad-hoc basis in the future. Our study protocol can be adapted to other regions and settings and is transferable to other infectious diseases. TRIAL REGISTRATION: DRKS.de, German Clinical Trials Register (DRKS), Identifier: DRKS00023418 , Registered on 28 October 2020.

Angiotensin II-mediated nondipping during sleep in healthy humans: effects on baroreflex function at subsequent daytime.

Blood pressure dipping at night is mediated by sleep-inherent, active downregulation of sympathetic vascular tone. Concomitantly, activity of the renin-angiotensin system is reduced, which might contribute to the beneficial effect of baroreflex downward resetting on daytime blood pressure homeostasis. To evaluate whether experimental nondipping mediated by angiotensin II during sleep would alter blood pressure and baroreflex function the next day in healthy humans, angiotensin-II or placebo (saline) was infused for a 7-h period at night, preventing blood pressure dipping in 11 sleeping normotensive individuals (5 males, balanced, crossover design). Baroreflex function was assessed about 1 h upon awakening and stop of infusion via microneurographic recordings of muscle sympathetic nerve activity (MSNA), showing that resting MSNA was significantly increased following angiotensin II nondipping compared with placebo (P = 0.029), whereas blood pressure and heart rate remained unchanged. Baroreflex sensitivity in response to vasoactive drug challenge was preserved, and neuroendocrine markers of fluid balance and electrolytes did not differ between conditions. Ambulatory blood pressure during subsequent daytime was not altered. Data were compared with analog experiments previously performed within the same subjects during awake daytime (ANCOVA). We conclude that angiotensin-II mediated nocturnal nondipping did not induce blood pressure elevation at subsequent daytime in healthy humans but was linked to increased vasoconstrictive sympathetic activity. This is in contrast to a prolonged increase in blood pressure in corresponding daytime experiments of the same individuals. Evidently, sleep strongly preserves normotensive blood pressure homeostasis in healthy humans.

Prolonged blood pressure elevation following continuous infusion of angiotensin II-a baroreflex study in healthy humans.

ANG II interacts with the sympathetic nervous system at central nervous blood pressure-regulating structures, including the baroreflex. It is unknown whether prolonged BP elevation mediated by high ANG II plasma levels could induce a persistent shift of the central nervous baroreflex setpoint, lasting beyond the short ANG II plasmatic half time of a few seconds, thereby consolidating elevated BP and/or increased SNA in healthy humans. In a blinded crossover design, ANG II or placebo (saline) was infused for a 6-h period in 12 resting normotensive students (6 males, 6 females) raising BP to borderline hypertensive levels. Between 60 and 120 min after the infusion period, muscle sympathetic nerve activity (MSNA) was assessed microneurographically and correlated with oscillometric BP measurements and heart rate at supine rest (baseline) and during pharmacologic baroreceptor challenge. Infusion of ANG II increased BP to borderline-hypertensive levels, as intended, whereas heart rate remained unaltered. At baroreflex assessment (i.e., 60-120 min after end of infusion period), systolic BP was significantly higher compared with placebo (Δ8.4 ± 3.1 mmHg; P < 0.05), whereas diastolic values were nearly equal between conditions. Baseline MSNA was neither decreased nor increased, and baroreflex sensitivity to vasoactive drug challenge was not altered. Our results show that elevation of ANG II plasma levels over 6 h was able to increase systolic, but not diastolic, BP far beyond blood-mediated ANG II effects. MSNA or heart rate did not counter-regulate this BP elevation, indicating that ANG II had sustainably reset the central nervous BP threshold of sympathetic baroreflex function to accept elevated BP input signals without counter-regulatory response.

[A curricular training of fourth year medical students in writing discharge summaries: the graduate view after two years]. / Curriculare Übung zum Verfassen von Arztbriefen im vierten Jahr des Medizinstudiums - Einschätzungen der Teilnehmer nach zwei Jahren.

BACKGROUND: Preparing high quality discharge summaries is difficult for first year residents. For 5 years we have been training fourth year students how to write discharge summaries. Our goal is to facilitate the students' start into clinical work. Moreover, we intend to provide the students with a scheme to better memorize patients' histories. Two years after the tutorial the graduates were asked to evaluate the tutorial and to comment on its learning effects. METHODS: A total of 1228 fourth year students wrote a discharge summary on a patient in whose care the specific student was involved during his or her training in internal medicine. All summaries were read, commented on and graded by a consultant. Two years after the tutorial 310 graduates were invited to complete an online survey on this tutorial. RESULTS: 106 (34%) of all invited graduates completed the survey. The opinions on the tutorial greatly differed. In principal the students agreed that the tutorial was an important part of medical training and helped to better structure patients' medical data. The majority of the surveyed graduates, however, were not convinced of its practical usefulness for daily work. The students with the poorer grading found their grade less appropriate than the students with the better grading. CONCLUSIONS: Though our main goal could not be achieved in the view of the graduates, the overall opinion was rather positive. Problems with this kind of tutorial lay in the enormous effort of correction and in the discouraging effect of grading on the students with difficulties in the task.

Question-writing as a learning tool for students--outcomes from curricular exams.

BACKGROUND: Writing exam questions can be a valuable learning tool. We asked students to construct multiple choice questions for curricular exams in Internal Medicine. The questions for the particular exams were chosen from a pool of at least 300 student-written questions. The uncorrected pool was accessible to all students. We studied the influence of this approach on the students' learning habits and their test results. We hypothesized that creating a pool of their own questions for the exams could encourage students to discuss the learning material. METHODS: All students had to pass 4 exams in 7 fields of Internal Medicine. Three exams were comprised of 20 questions, and we applied the new method in one of these exams. The fourth exam was comprised of 30 questions, 15 of which were chosen from a students' pool. After all exams had been completed we asked the students to fill in a web-based questionnaire on their learning habits and their views on the new approach. The test-results were compared to the results of the lecturers' questions that defined high and low performing students. RESULTS: A total of 102 students completed all four exams in a row, 68 of whom filled in the questionnaire. Low performing students achieved significantly better results in the students' questions. There was no difference in the number of constructed questions between both groups of students. The new method did not promote group work significantly. However, high performing students stated a stronger wish to be rewarded by good performance. CONCLUSIONS: Creating a curricular exam by choosing questions from a pool constructed by students did not influence the learning habits significantly and favored low performing students. Since the high performing students sought to be rewarded for their efforts, we do not consider the approach applied in our study to be appropriate.

One-year surveillance of SARS-CoV-2 transmission of the ELISA cohort: A model for population-based monitoring of infection risk.

With newly rising coronavirus disease 2019 (COVID-19) cases, important data gaps remain on (i) long-term dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates in fixed cohorts (ii) identification of risk factors, and (iii) establishment of effective surveillance strategies. By polymerase chain reaction and antibody testing of 1% of the local population and >90,000 app-based datasets, the present study surveilled a catchment area of 300,000 inhabitants from March 2020 to February 2021. Cohort (56% female; mean age, 45.6 years) retention was 75 to 98%. Increased risk for seropositivity was detected in several high-exposure groups, especially nurses. Unreported infections dropped from 92 to 29% during the study. "Contact to COVID-19-affected" was the strongest risk factor, whereas public transportation, having children in school, or tourism did not affect infection rates. With the first SARS-CoV-2 cohort study, we provide a transferable model for effective surveillance, enabling monitoring of reinfection rates and increased preparedness for future pandemics.

Effects of a rater training on rating accuracy in a physical examination skills assessment.

BACKGROUND: The accuracy and reproducibility of medical skills assessment is generally low. Rater training has little or no effect. Our knowledge in this field, however, relies on studies involving video ratings of overall clinical performances. We hypothesised that a rater training focussing on the frame of reference could improve accuracy in grading the curricular assessment of a highly standardised physical head-to-toe examination. METHODS: Twenty-one raters assessed the performance of 242 third-year medical students. Eleven raters had been randomly assigned to undergo a brief frame-of-reference training a few days before the assessment. 218 encounters were successfully recorded on video and re-assessed independently by three additional observers. Accuracy was defined as the concordance between the raters' grade and the median of the observers' grade. After the assessment, both students and raters filled in a questionnaire about their views on the assessment. RESULTS: Rater training did not have a measurable influence on accuracy. However, trained raters rated significantly more stringently than untrained raters, and their overall stringency was closer to the stringency of the observers. The questionnaire indicated a higher awareness of the halo effect in the trained raters group. Although the self-assessment of the students mirrored the assessment of the raters in both groups, the students assessed by trained raters felt more discontent with their grade. CONCLUSIONS: While training had some marginal effects, it failed to have an impact on the individual accuracy. These results in real-life encounters are consistent with previous studies on rater training using video assessments of clinical performances. The high degree of standardisation in this study was not suitable to harmonize the trained raters' grading. The data support the notion that the process of appraising medical performance is highly individual. A frame-of-reference training as applied does not effectively adjust the physicians' judgement on medical students in real-live assessments.

Differences between students and physicians in their entitlement towards procedural skills education--a needs assessment of skills training in internal medicine.

OBJECTIVE: Procedural skills education has a high priority for medical students. However, it is not clear what kind of skills they consider important and whether their perception differs from the physicians' view. METHODS: We conducted a survey on 26 skills in internal medicine among medical students and physicians. Ninety-five fourth year and 62 final year students along with 67 physicians working in medical departments participated in the survey. A similar but smaller survey was completed earlier before the implementation of a skills training at the faculty. RESULTS: Students generally preferred technically complex skills while, in contrast, physicians found "bed-side-skills" more important. The result was independent of the students' participation in the skills training or of the physicians' experience. A similar result was achieved in the smaller survey before the implementation of the skills training. CONCLUSION: Students and physicians significantly differ in their entitlement towards procedural skills education. This should be considered when educational strategies are being discussed.