Cardiothoracic ratio in postmortem computed tomography: reliability and threshold for the diagnosis of cardiomegaly

The aim of this study was to evaluate the reliability of the cardiothoracic ratio (CTR) in postmortem computed tomography (PMCT) and to assess a CTR threshold for the diagnosis of cardiomegaly based on the weight of the heart at autopsy. PMCT data of 170 deceased human adults were retrospectively evaluated by two blinded radiologists. The CTR was measured on axial computed tomography images and the actual cardiac weight was weighed at autopsy. Inter-rater reliability, sensitivity, and specificity were calculated. Receiver operating characteristic curves were calculated to assess enlarged heart weight by CTR. The autopsy definition of cardiomegaly was based on normal values of the Zeek method (within a range of both, one or two SD) and the Smith method (within the given range). Intra-class correlation coefficients demonstrated excellent agreements (0.983) regarding CTR measurements. In 105/170 (62 %) cases the CTR in PMCT was >0.5, indicating enlarged heart weight, according to clinical references. The mean heart weight measured in autopsy was 405 ± 105 g. As a result, 114/170 (67 %) cases were interpreted as having enlarged heart weights according to the normal values of Zeek within one SD, while 97/170 (57 %) were within two SD. 100/170 (59 %) were assessed as enlarged according to Smith's normal values. The sensitivity/specificity of the 0.5 cut-off of the CTR for the diagnosis of enlarged heart weight was 78/71 % (Zeek one SD), 74/55 % (Zeek two SD), and 76/59 % (Smith), respectively. The discriminative power between normal heart weight and cardiomegaly was 79, 73, and 74 % for the Zeek (1SD/2SD) and Smith methods respectively. Changing the CTR threshold to 0.57 resulted in a minimum specificity of 95 % for all three definitions of cardiomegaly. With a CTR threshold of 0.57, cardiomegaly can be identified with a very high specificity. This may be useful if PMCT is used by forensic pathologists as a screening tool for medico-legal autopsies.

Intra-session test-retest reliability of pelvic floor muscle electromyography during running

INTRODUCTION AND HYPOTHESIS The prevalence of female stress urinary incontinence is high, and young adults are also affected, including athletes, especially those involved in "high-impact" sports. To date there have been almost no studies testing pelvic floor muscle (PFM) activity during dynamic functional whole body movements. The aim of this study was the description and reliability test of PFM activity and time variables during running. METHODS A prospective cross-sectional study including ten healthy female subjects was designed with the focus on the intra-session test-retest reliability of PFM activity and time variables during running derived from electromyography (EMG) and accelerometry. RESULTS Thirteen variables were identified based on ten steps of each subject: Six EMG variables showed good reliability (ICC 0.906-0.942) and seven time variables did not show good reliability (ICC 0.113-0.731). Time variables (e.g. time difference between heel strike and maximal acceleration of vaginal accelerator) showed low reliability. However, relevant PFM EMG variables during running (e.g., pre-activation, minimal and maximal activity) could be identified and showed good reliability. CONCLUSION Further adaptations regarding measurement methods should be tested to gain better control of the kinetics and kinematics of the EMG probe and accelerometers. To our knowledge this is the first study to test the reliability of PFM activity and time variables during dynamic functional whole body movements. More knowledge of PFM activity and time variables may help to provide a deeper insight into physical strain with high force impacts and important functional reflexive contraction patterns of PFM to maintain or to restore continence.

Precipitation isoscape of high reliefs: interpolation scheme designed and tested for monthly resolved precipitation oxygen isotope records of an Alpine domain

Stable oxygen isotope composition of atmospheric precipitation (δ18Op) was scrutinized from 39 stations distributed over Switzerland and its border zone. Monthly amount-weighted δ18Op values averaged over the 1995–2000 period showed the expected strong linear altitude dependence (−0.15 to −0.22‰ per 100 m) only during the summer season (May–September). Steeper gradients (~ −0.56 to −0.60‰ per 100 m) were observed for winter months over a low elevation belt, while hardly any altitudinal difference was seen for high elevation stations. This dichotomous pattern could be explained by the characteristically shallower vertical atmospheric mixing height during winter season and provides empirical evidence for recently simulated effects of stratified atmospheric flow on orographic precipitation isotopic ratios. This helps explain "anomalous" deflected altitudinal water isotope profiles reported from many other high relief regions. Grids and isotope distribution maps of the monthly δ18Op have been calculated over the study region for 1995–1996. The adopted interpolation method took into account both the variable mixing heights and the seasonal difference in the isotopic lapse rate and combined them with residual kriging. The presented data set allows a point estimation of δ18Op with monthly resolution. According to the test calculations executed on subsets, this biannual data set can be extended back to 1992 with maintained fidelity and, with a reduced station subset, even back to 1983 at the expense of faded reliability of the derived δ18Op estimates, mainly in the eastern part of Switzerland. Before 1983, reliable results can only be expected for the Swiss Plateau since important stations representing eastern and south-western Switzerland were not yet in operation.

Functional connectivity in BOLD and CBF data: similarity and reliability of resting brain networks

Resting-state functional connectivity (FC) fMRI (rs-fcMRI) offers an appealing approach to mapping the brain's intrinsic functional organization. Blood oxygen level dependent (BOLD) and arterial spin labeling (ASL) are the two main rs-fcMRI approaches to assess alterations in brain networks associated with individual differences, behavior and psychopathology. While the BOLD signal is stronger with a higher temporal resolution, ASL provides quantitative, direct measures of the physiology and metabolism of specific networks. This study systematically investigated the similarity and reliability of resting brain networks (RBNs) in BOLD and ASL. A 2×2×2 factorial design was employed where each subject underwent repeated BOLD and ASL rs-fcMRI scans on two occasions on two MRI scanners respectively. Both independent and joint FC analyses revealed common RBNs in ASL and BOLD rs-fcMRI with a moderate to high level of spatial overlap, verified by Dice Similarity Coefficients. Test-retest analyses indicated more reliable spatial network patterns in BOLD (average modal Intraclass Correlation Coefficients: 0.905±0.033 between-sessions; 0.885±0.052 between-scanners) than ASL (0.545±0.048; 0.575±0.059). Nevertheless, ASL provided highly reproducible (0.955±0.021; 0.970±0.011) network-specific CBF measurements. Moreover, we observed positive correlations between regional CBF and FC in core areas of all RBNs indicating a relationship between network connectivity and its baseline metabolism. Taken together, the combination of ASL and BOLD rs-fcMRI provides a powerful tool for characterizing the spatiotemporal and quantitative properties of RBNs. These findings pave the way for future BOLD and ASL rs-fcMRI studies in clinical populations that are carried out across time and scanners.

University and school students' motivation for effortful thinking: Factor structure, reliability, and validity of the German Need for Cognition Scale

Need for cognition (NFC) reflects a relatively stable trait regarding the degree to which one enjoys and engages in cognitive endeavors. We examined whether the previously demonstrated one-dimensional structure of the German NFC Scale could be replicated in three samples of undergraduates and secondary school students. Moreover, we investigated the test-retest reliability of the German NFC Scale, which has not yet been tested. Further, we investigated whether the scale would be valid in a sample of secondary school students. Multigroup confirmatory factor analyses established the one-dimensional factor structure of the long form as well as the short form of the German NFC Scale for undergraduates (N = 559), students of academic track secondary schools (German Gymnasium; N = 555), and students of vocational track secondary schools (German Realschule; N = 486). The scale proved to have a high test-retest reliability in a university student sample (N = 43). For secondary school students, we again found a high test-retest reliability (N = 157), and also found the scale to be valid (N = 181).

Quality Control for SP Performance Regarding Patient Portrayal in a High-Stakes OSCE

Introduction Since the quality of patient portrayal of standardized patients (SPs) during an Objective Structured Clinical Exam (OSCE) has a major impact on the reliability and validity of the exam, quality control should be initiated. Literature about quality control of SP’s performance focuses on feedback [1, 2] or completion of checklists [3, 4]. Since we did not find a published instrument meeting our needs for the assessment of patient portrayal, we developed such an instrument after being inspired by others [5] and used it in our high-stakes exam. Methods SP trainers from all five Swiss medical faculties collected and prioritized quality criteria for patient portrayal. Items were revised with the partners twice, based on experiences during OSCEs. The final instrument contains 14 criteria for acting (i.e. adequate verbal and non-verbal expression) and standardization (i.e. verbatim delivery of the first sentence). All partners used the instrument during a high-stakes OSCE. Both, SPs and trainers were introduced to the instrument. The tool was used in training (more than 100 observations) and during the exam (more than 250 observations). FAIR_OSCE The list of items to assess the quality of the simulation by SPs was primarily developed and used to provide formative feedback to the SPs in order to help them to improve their performance. It was therefore named “Feedbackstruckture for the Assessment of Interactive Role play in Objective Structured Clinical Exams (FAIR_OSCE). It was also used to assess the quality of patient portrayal during the exam. The results were calculated for each of the five faculties individually. Formative evaluation was given to the five faculties with individual feedback without revealing results of other faculties other than overall results. Results High quality of patient portrayal during the exam was documented. More than 90% of SP performances were rated to be completely correct or sufficient. An increase in quality of performance between training and exam was noted. In example the rate of completely correct reaction in medical tests increased from 88% to 95%. 95% completely correct reactions together with 4% sufficient reactions add up to 99% of the reactions meeting the requirements of the exam. SP educators using the instrument reported an augmentation of SPs performance induced by the use of the instrument. Disadvantages mentioned were high concentration needed to explicitly observe all criteria and cumbersome handling of the paper-based forms. Conclusion We were able to document a very high quality of SP performance in our exam. The data also indicate that our training is effective. We believe that the high concentration needed using the instrument is well invested, considering the observed augmentation of performance. The development of an iPad based application for the form is planned to address the cumbersome handling of the paper.

German Total Ankle Replacement Register of the German Foot and Ankle Society (D. A. F.) - presentation of design and reliability of the data as well as first results

INTRODUCTION Even though arthroplasty of the ankle joint is considered to be an established procedure, only about 1,300 endoprostheses are implanted in Germany annually. Arthrodeses of the ankle joint are performed almost three times more often. This may be due to the availability of the procedure - more than twice as many providers perform arthrodesis - as well as the postulated high frequency of revision procedures of arthroplasties in the literature. In those publications, however, there is often no clear differentiation between revision surgery with exchange of components, subsequent interventions due to complications and subsequent surgery not associated with complications. The German Orthopaedic Foot and Ankle Association's (D. A. F.) registry for total ankle replacement collects data pertaining to perioperative complications as well as cause, nature and extent of the subsequent interventions, and postoperative patient satisfaction. MATERIAL AND METHODS The D. A. F.'s total ankle replacement register is a nation-wide, voluntary registry. After giving written informed consent, the patients can be added to the database by participating providers. Data are collected during hospital stay for surgical treatment, during routine follow-up inspections and in the context of revision surgery. The information can be submitted in paper-based or online formats. The survey instruments are available as minimum data sets or scientific questionnaires which include patient-reported outcome measures (PROMs). The pseudonymous clinical data are collected and evaluated at the Institute for Evaluative Research in Medicine, University of Bern/Switzerland (IEFM). The patient-related data remain on the register's module server in North Rhine-Westphalia, Germany. The registry's methodology as well as the results of the revisions and patient satisfaction for 115 patients with a two year follow-up period are presented. Statistical analyses are performed with SAS™ (Version 9.4, SAS Institute, Inc., Cary, NC, USA). RESULTS About 2½ years after the register was launched there are 621 datasets on primary implantations, 1,427 on follow-ups and 121 records on re-operation available. 49 % of the patients received their implants due to post-traumatic osteoarthritis, 27 % because of a primary osteoarthritis and 15 % of patients suffered from a rheumatic disease. More than 90 % of the primary interventions proceeded without complications. Subsequent interventions were recorded for 84 patients, which corresponds to a rate of 13.5 % with respect to the primary implantations. It should be noted that these secondary procedures also include two-stage procedures not due to a complication. "True revisions" are interventions with exchange of components due to mechanical complications and/or infection and were present in 7.6 % of patients. 415 of the patients commented on their satisfaction with the operative result during the last follow-up: 89.9 % of patients evaluate their outcome as excellent or good, 9.4 % as moderate and only 0.7 % (3 patients) as poor. In these three cases a component loosening or symptomatic USG osteoarthritis was present. Two-year follow-up data using the American Orthopedic Foot and Ankle Society Ankle and Hindfoot Scale (AOFAS-AHS) are already available for 115 patients. The median AOFAS-AHS score increased from 33 points preoperatively to more than 80 points three to six months postoperatively. This increase remained nearly constant over the entire two-year follow-up period. CONCLUSION Covering less than 10 % of the approximately 240 providers in Germany and approximately 12 % of the annually implanted total ankle-replacements, the D. A. F.-register is still far from being seen as a national registry. Nevertheless, geographical coverage and inclusion of "high-" (more than 100 total ankle replacements a year) and "low-volume surgeons" (less than 5 total ankle replacements a year) make the register representative for Germany. The registry data show that the number of subsequent interventions and in particular the "true revision" procedures are markedly lower than the 20 % often postulated in the literature. In addition, a high level of patient satisfaction over the short and medium term is recorded. From the perspective of the authors, these results indicate that total ankle arthroplasty - given a correct indication and appropriate selection of patients - is not inferior to an ankle arthrodesis concerning patients' satisfaction and function. First valid survival rates can be expected about 10 years after the register's start.

Intra-Rater and Inter-Rater Reliability of a Medical Record Abstraction Study on Transition of Care after Childhood Cancer.

BACKGROUND The abstraction of data from medical records is a widespread practice in epidemiological research. However, studies using this means of data collection rarely report reliability. Within the Transition after Childhood Cancer Study (TaCC) which is based on a medical record abstraction, we conducted a second independent abstraction of data with the aim to assess a) intra-rater reliability of one rater at two time points; b) the possible learning effects between these two time points compared to a gold-standard; and c) inter-rater reliability. METHOD Within the TaCC study we conducted a systematic medical record abstraction in the 9 Swiss clinics with pediatric oncology wards. In a second phase we selected a subsample of medical records in 3 clinics to conduct a second independent abstraction. We then assessed intra-rater reliability at two time points, the learning effect over time (comparing each rater at two time-points with a gold-standard) and the inter-rater reliability of a selected number of variables. We calculated percentage agreement and Cohen's kappa. FINDINGS For the assessment of the intra-rater reliability we included 154 records (80 for rater 1; 74 for rater 2). For the inter-rater reliability we could include 70 records. Intra-rater reliability was substantial to excellent (Cohen's kappa 0-6-0.8) with an observed percentage agreement of 75%-95%. In all variables learning effects were observed. Inter-rater reliability was substantial to excellent (Cohen's kappa 0.70-0.83) with high agreement ranging from 86% to 100%. CONCLUSIONS Our study showed that data abstracted from medical records are reliable. Investigating intra-rater and inter-rater reliability can give confidence to draw conclusions from the abstracted data and increase data quality by minimizing systematic errors.

High-precision confocal reflection measurement for two dimensional refractive index mapping of optical fibers

We introduce a new fiber-optical approach for reflection based refractive index mapping. Our approach leads to improved stability and reliability over existing free-space confocal instruments and significantly cuts alignment efforts and reduces the number of components needed. Other than properly cleaved fiber end-faces, this setup requires no additional sample preparation. The instrument is calibrated by means of a set of samples with known refractive indices. The index steps of commercially available fibers are measured accurately down to < 10⁻³. The precision limit of the instrument is currently of the order of 10⁻⁴.

Pelvic floor muscle electromyography during different running speeds: an exploratory and reliability study.

PURPOSE Stress urinary incontinence (SUI) affects women of all ages including young athletes, especially those involved in high-impact sports. To date, hardly any studies are available testing pelvic floor muscles (PFM) during sports activities. The aim of this study was the description and reliability test of six PFM electromyography (EMG) variables during three different running speeds. The secondary objective was to evaluate whether there was a speed-dependent difference between the PFM activity variables. METHODS This trial was designed as an exploratory and reliability study including ten young healthy female subjects to characterize PFM pre-activity and reflex activity during running at 7, 9 and 11 km/h. Six variables for each running speed, averaged over ten steps per subject, were presented descriptively, tested regarding their reliability (Friedman, ICC, SEM, MD) and speed difference (Friedman). RESULTS PFM EMG variables varied between 67.6 and 106.1 %EMG, showed no systematic error and were low for SEM and MD using the single value model. Applying the average model over ten steps, ICC (3,k) were >0.75 and SEM and MD about 50 % lower than for the single value model. Activity was found to be highest in 11 km/h. CONCLUSION EMG variables showed excellent ICC and very low SEM and MD. Further studies should investigate inter-session reliability and PFM reactivity patterns of SUI patients using the average over ten steps for each variable as it showed very high ICC and very low SEM and MD. Subsequently, longer running distances and other high-impact sports disciplines could be studied.

A systematic evaluation of the Zr-in-rutile thermometer in ultra-high temperature (UHT) rocks

The Zr-in-rutile geothermometer is potentially a widely applicable tool to estimate peak metamorphic temperatures in rocks from diverse geological settings. In order to evaluate its usefulness and reliability to record and preserve high temperatures in granulite facies rocks, rutile from UHT rocks was investigated to assess different mechanisms of Zr (re-)distribution following cooling from high temperature. Granulite facies paragneisses from the lowermost part of the Ivrea Zone, Italy, incorporated as thin sheets into the extensive basaltic body of the Mafic Complex were selected for this study. The results show that Zr-in-rutile thermometry, if properly applied, is well suited to identify and study UHT terranes as it preserves a record of temperatures up to 1190 °C, although the thermometer is susceptible to partial post-peak metamorphic resetting by Zr diffusion. Texturally homogeneous rutile grains preserve Zr concentrations corresponding to temperatures of prograde rutile growth. Diverse rutile textures and relationships between some rutile host grains and included or adjacent Zr-bearing phases bear testimony to varying mechanisms of partial redistribution and resetting of Zr in rutile during cooling and link Zr-in-rutile temperatures to different steps of the metamorphic evolution. Rutile grains that equilibrated their Zr concentrations at temperatures above 1070 °C (i.e. 1.1 wt% Zr) could not retain all Zr in the rutile structure during cooling and exsolved baddeleyite (ZrO2). By subsequent reaction of baddeleyite exsolution lamellae with SiO2, zircon needles formed before the system finally closed at 650–700 °C without significant net loss of Zr from the whole host rutile grain. By reintegration of zircon exsolution needles, peak metamorphic temperatures of up to 1190 °C are derived for the studied rocks, which demonstrates the suitability of this solution thermometer to record UHT conditions and also confirms the extraordinary geological setting of the lowermost part of the Ivrea Zone.