Search results for "Observer Variation"
showing 10 items of 156 documents
Automatic algorithm for monitoring systolic pressure variation and difference in pulse pressure.
2009
BACKGROUND: Difference in pulse pressure (dPP) reliably predicts fluid responsiveness in patients. We have developed a respiratory variation (RV) monitoring device (RV monitor), which continuously records both airway pressure and arterial blood pressure (ABP). We compared the RV monitor measurements with manual dPP measurements. METHODS: ABP and airway pressure (PAW) from 24 patients were recorded. Data were fed to the RV monitor to calculate dPP and systolic pressure variation in two different ways: (a) considering both ABP and PAW (RV algorithm) and (b) ABP only (RV(slim) algorithm). Additionally, ABP and PAW were recorded intraoperatively in 10-min intervals for later calculation of dPP …
Improvement of inter-rater reliability of PANSS items and subscales by a standardized rater training.
1998
The present evaluation focused on the inter-rater reliability of single items and subscales of the Positive and Negative Syndrome Scale (PANSS) before and after a standardized rater training. The results of two independent studies comprising n=23 (study I) and n=12 (study II) psychiatrists and videotaped interviews with schizophrenic patients were analysed. Chance-corrected coefficients of rating agreement with expert standards (weighted kappa) were computed for single items and subscales of the PANSS. The results clearly demonstrate the importance of rater trainings. After three training sessions, 90% of the PANSS items reached an acceptable level of reliability (kappa(w)>0.40) in both eva…
Transpalpebral tonometry: reliability and comparison with Goldmann applanation tonometry and palpation in healthy volunteers
2005
Background/aim: TGDc-01 is a new, portable, transpalpebral tonometry device. The aim of this study was to evaluate the reproducibility of this method, including intraobserver and interobserver deviations, and to compare the results with those of Goldmann applanation tonometry and palpation of intraocular pressure (IOP). Methods: A total of 40 eyes of 20 healthy volunteers were included. Two independent parallel observers (1 and 2) performed three replicate measurements per eye, respectively, both using TGDc01 tonometry, one observer (3) performed three replicate measurements using Goldmann applanation tonometry, and one observer (4) measured the IOP via palpation. Intraindividual deviations…
Improved T2* assessment in liver iron overload by magnetic resonance imaging.
2009
In the clinical MRI practice, it is common to assess liver iron overload by T2* multi-echo gradient-echo images. However, there is no full consensus about the best image analysis approach for the T2* measurements. The currently used methods involve manual drawing of a region of interest (ROI) within MR images of the liver. Evaluation of a representative liver T2* value is done by fitting an appropriate model to the signal decay within the ROIs vs. the echo time. The resulting T2* value may depend on both ROI placement and choice of the signal decay model. The aim of this study was to understand how the choice of the analysis methodology may affect the accuracy of T2* measurements. A softwar…
Multislice multiecho T2* cardiovascular magnetic resonance for detection of the heterogeneous distribution of myocardial iron overload.
2006
Purpose To assess the tissue iron concentration of the left ventricle (LV) using a multislice, multiecho T2* MR technique and a segmental analysis. Materials and Methods T2* multiecho MRI was performed in 53 thalassemia major patients. Three short-axis views of the LV were obtained and analyzed with custom-written software. The myocardium was automatically segmented into 12 segments. The T2* value on each segment as well as the global T2* value were calculated. Cine dynamic images were also obtained to evaluate biventricular function parameters by quantitative analysis. Results For the T2* global value, the coefficient of variation (CoV) for intra-/interobserver and interstudy reproducibili…
Transthoracic three-dimensional echocardiographic volumetry of distorted left ventricles using rotational scanning
1997
The purpose of this study was to evaluate the relation of transthoracic three- and two-dimensional echocardiographic left ventricular volumetry to cineventriculographic volumetry. Twenty-five patients with distorted left ventricles were included in the study. To demonstrate the impact of acquiring data by rotational scanning, we performed three- and two-dimensional echocardiography in 36 latex ventricles with data acquisition in different areas of the ultrasound sectors. Interobserver and intraobserver variability were calculated to test for reproducibility. The three-dimensional imaging system consisted of a rotation motor device, a transthoracic 2.5 MHz transducer, a conventional ultrasou…
The effects of an amine fluoride/stannous fluoride and an antimicrobial host protein mouthrinse on supragingival plaque regrowth.
2004
BACKGROUND: Chlorhexidine (CHX)-containing mouthrinses are recommended as adjuncts to mechanical oral hygiene. The problem associated with side effects, however, has stimulated the search for alternative antiplaque agents. The aim of this study was to investigate the plaque inhibitory effects of two mouthrinses containing amine fluoride/stannous fluoride (ASF) and antimicrobial host proteins (lactoperoxidase, lysozyme and lactoferrin; LLL), respectively. METHODS: The study was an observer-masked, randomized 4x4 Latin square cross-over design balanced for carryover effects, involving 12 healthy volunteers in a 4-day plaque regrowth model. A 0.12% CHX mouthrinse and a saline solution served a…
Reliability of measuring the fat content of the lumbar vertebral marrow and paraspinal muscles using MRI mDIXON-quant sequence
2018
PURPOSE We aimed to assess the reliability of measuring the fat content of the lumbar vertebral marrow and the paraspinal muscles using magnetic resonance imaging (MRI) mDIXON-Quant sequence. METHODS Thirty-one healthy volunteers were included. All participants underwent liver mDIXON-Quant imaging on a 3.0 T Philips MRI scanner by observer A. Within two weeks, observer B repeated the scan. After the examination, each observer independently measured the fat content of the third lumbar vertebra (L3), and the psoas (PS), erector spinae (ES), and multifidus (MF) muscles on central L3 axial images. After two weeks, each observer repeated the same measurements. They were blinded to their previous…
The Calgary Depression Rating Scale for Schizophrenia: development and interrater reliability of a German version (CDSS-G)
1999
A German version of the Calgary Depression Rating Scale for Schizophrenia (CDSS-G) approved by the author of the original scale is presented comprising a semi-structured interview for 9 items to sensitively and specifically assess depression in schizophrenia and related disorders. The process of translation is outlined and the finally derived CDSS-G was investigated with respect to interrater reliability in three studies. To keep comparability with the CDSS source version a standard procedure was used. Two trained raters jointly assessed ten schizophrenic patients (study I). In a second study, videotapes with the CDSS-G were presented to clinically inexperienced raters (study II, N = 14/15)…
Standardized rater training for the Hamilton Depression Rating Scale (HAMD-17) in psychiatric novices.
2003
Abstract Background: Despite the long and widespread use of the Hamilton Depression Rating Scale (HAMD), standardized reliability studies in inexperienced raters are not available. Methods: Rater training was carried using three videotaped interviews with depressed patients in 21 psychiatric novices who had negligible previous experience with the HAMD. Chance-corrected coefficients of rating agreement with expert standards (weighted κ , ICC) were computed for single items and the total score of the HAMD. Results: The results demonstrate sufficiently high interrater reliability ( κ >0.60) for most of the HAMD items and the total score (ICC=0.57–0.73). Three standardized HAMD training session…