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Selected AbstractsAn Independent Evaluation of Four Quantitative Emergency Department Crowding ScalesACADEMIC EMERGENCY MEDICINE, Issue 11 2006Spencer S. Jones MStat Background Emergency department (ED) overcrowding has become a frequent topic of investigation. Despite a significant body of research, there is no standard definition or measurement of ED crowding. Four quantitative scales for ED crowding have been proposed in the literature: the Real-time Emergency Analysis of Demand Indicators (READI), the Emergency Department Work Index (EDWIN), the National Emergency Department Overcrowding Study (NEDOCS) scale, and the Emergency Department Crowding Scale (EDCS). These four scales have yet to be independently evaluated and compared. Objectives The goals of this study were to formally compare four existing quantitative ED crowding scales by measuring their ability to detect instances of perceived ED crowding and to determine whether any of these scales provide a generalizable solution for measuring ED crowding. Methods Data were collected at two-hour intervals over 135 consecutive sampling instances. Physician and nurse agreement was assessed using weighted , statistics. The crowding scales were compared via correlation statistics and their ability to predict perceived instances of ED crowding. Sensitivity, specificity, and positive predictive values were calculated at site-specific cut points and at the recommended thresholds. Results All four of the crowding scales were significantly correlated, but their predictive abilities varied widely. NEDOCS had the highest area under the receiver operating characteristic curve (AROC) (0.92), while EDCS had the lowest (0.64). The recommended thresholds for the crowding scales were rarely exceeded; therefore, the scales were adjusted to site-specific cut points. At a site-specific cut point of 37.19, NEDOCS had the highest sensitivity (0.81), specificity (0.87), and positive predictive value (0.62). Conclusions At the study site, the suggested thresholds of the published crowding scales did not agree with providers' perceptions of ED crowding. Even after adjusting the scales to site-specific thresholds, a relatively low prevalence of ED crowding resulted in unacceptably low positive predictive values for each scale. These results indicate that these crowding scales lack scalability and do not perform as designed in EDs where crowding is not the norm. However, two of the crowding scales, EDWIN and NEDOCS, and one of the READI subscales, bed ratio, yielded good predictive power (AROC >0.80) of perceived ED crowding, suggesting that they could be used effectively after a period of site-specific calibration at EDs where crowding is a frequent occurrence. [source] Screening for diabetes in Indigenous populations using glycated haemoglobin: sensitivity, specificity, post-test likelihood and risk of diseaseDIABETIC MEDICINE, Issue 7 2005K. G. Rowley Abstract Aims Screening for diabetes using glycated haemoglobin (HbA1c) offers potential advantages over fasting glucose or oral glucose tolerance testing. Current recommendations advise against the use of HbA1c for screening but test properties may vary systematically across populations, according to the diabetes prevalence and risk. We aimed to: (i) characterize the properties of test cut-offs of HbA1c for diagnosis of diabetes relative to a diagnosis based on a fasting plasma glucose concentration of 7.0 mmol/l for high-risk Indigenous populations; and (ii) examine test properties across a range of diabetes prevalence from 5 to 30%. Methods Data were collected from Aboriginal and Torres Strait Islander communities in Australia and a Canadian First Nations community (diabetes prevalence 12,22%) in the course of diabetes diagnostic and risk factor screening programmes (n = 431). Screening test properties were analyzed for the range of HbA1c observed (3,12.9%). Results In separate and pooled analyses, a HbA1c cut point of 7.0% proved the optimal limit for classifying diabetes, with summary analysis results of sensitivity = 73 (56,86)%, specificity = 98 (96,99)%, overall agreement (Youden's index) = 0.71, and positive predictive value (for an overall prevalence of 18%) = 88%. For diabetes prevalence from 5 to 30% the post-test likelihood of having diabetes given HbA1c = 7.0% (positive predictive value) ranged from 62.7 to 93.2%; for HbA1c < 7.0%, the post-test likelihood of having diabetes ranged from 4.5 to 27.7%. Conclusions The results converge with research on the likelihood of diabetes complications in supporting a HbA1c cut-off of 7.0% in screening for diabetes in epidemiological research. Glycated haemoglobin has potential utility in screening for diabetes in high-risk populations. [source] Imputation of SF-12 Health Scores for Respondents with Partially Missing DataHEALTH SERVICES RESEARCH, Issue 3 2005Honghu Liu Objective. To create an efficient imputation algorithm for imputing the SF-12 physical component summary (PCS) and mental component summary (MCS) scores when patients have one to eleven SF-12 items missing. Study Setting. Primary data collection was performed between 1996 and 1998. Study Design. Multi-pattern regression was conducted to impute the scores using only available SF-12 items (simple model), and then supplemented by demographics, smoking status and comorbidity (enhanced model) to increase the accuracy. A cut point of missing SF-12 items was determined for using the simple or the enhanced model. The algorithm was validated through simulation. Data Collection. Thirty-thousand-three-hundred and eight patients from 63 physician groups were surveyed for a quality of care study in 1996, which collected the SF-12 and other information. The patients were classified as "chronic" patients if they reported that they had diabetes, heart disease, asthma/chronic obstructive pulmonary disease, or low back pain. A follow-up survey was conducted in 1998. Principal Findings. Thirty-one percent of the patients missed at least one SF-12 item. Means of variance of prediction and standard errors of the mean imputed scores increased with the number of missing SF-12 items. Correlations between the observed and the imputed scores derived from the enhanced models were consistently higher than those derived from the simple model and the increments were significant for patients with ,6 missing SF-12 items (p<.03). Conclusion. Missing SF-12 items are prevalent and lead to reduced analytical power. Regression-based multi-pattern imputation using the available SF-12 items is efficient and can produce good estimates of the scores. The enhancement from the additional patient information can significantly improve the accuracy of the imputed scores for patients with ,6 items missing, leading to estimated scores that are as accurate as that of patients with <6 missing items. [source] The development and initial validation of the Terminally Ill Grief or Depression Scale (TIGDS)INTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 4 2005Vyjeyanthi S. Periyakoil Abstract Patients often experience ,preparatory-grief' as they cope with the dying process. Some may be depressed. The Terminally Ill Grief or Depression Scale (TIGDS), comprising grief and depression sub-scales, is a new self-report measure designed to differentiate between preparatory-grief and depression in adult inpatients. The initial 100-item inventory was assembled based on literature review, interviews with clinicians and dying patients and then shortened to 42 items based on consensus expert opinion. Validity and reliability were tested in a sample of 55 terminally ill adults. The consensus clinical opinion was used as the gold standard to differentiate between preparatory grief and depression. The intra-class correlation coefficient was high (it was calculated to estimate the test-retest reliability for the 47 patients who had completed the TIGDS twice , retest was administered 2 to 7 days after the initial test), ranging from 0.86 (grief) to 0.97 (depression). The validity of TIGDS was assessed using a receiver operating characteristic curve analysis, comparing the first test with the clinical criterion. The first and only variable and cut-point was the depression score (chi-square = 18.4,p < 0.001, cut point = 3). The sensitivity of the TIGDS was 0.727 and specificity was 0.886 for the depression = 3 cutoff score. The construct validity of the TIGDS was tested by comparing with the Hospital Anxiety and Depression Scale (HADS). The TIGDS depression subscale showed strong convergent validity and the TIGDS grief subscale showed strong discriminant validity with the HADS total score. Copyright © 2005 John Wiley & Sons, Ltd. [source] Status versus growth: The distributional effects of school accountability policiesJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 3 2010Helen F. Ladd Although the federal No Child Left Behind program judges the effectiveness of schools based on their students' achievement status, many policy analysts argue that schools should be measured, instead, by their students' achievement growth. Using a 10-year student-level panel data set from North Carolina, we examine how school-specific pressure associated with status and growth approaches to school accountability affect student achievement at different points in the prior-year achievement distribution. Achievement gains for students below the proficiency cut point emerge in schools failing either type of accountability standard, with the effects clearer for math than for reading. In contrast to prior research highlighting the possibility of educational triage, we find little or no evidence that failing schools in North Carolina ignore the students far below proficiency under either approach. Importantly, we find that the status, but not the growth, approach reduces the reading achievement of higher performing students. Our analysis suggests that the distributional effects of accountability pressure depend not only on the type of pressure for which schools are held accountable (status or growth), but also the tested subject. © 2010 by the Association for Public Policy Analysis and Management. [source] Screening for Alcohol Problems in the U.S.ALCOHOLISM, Issue 11 2002Ethnicity, General Population: Comparison of the CAGE, RAPS, RAPS4-QF by Gender, Service Utilization Background The purpose of this study was to compare the performance (sensitivity and specificity) of two brief screening instruments, CAGE and the Rapid Alcohol Problems Screen 4 (RAPS4), against ICD-10 and DSM-IV criteria for alcohol dependence and abuse in a representative sample of the U.S. adult household population by gender, ethnicity, and service utilization (emergency room and primary care) in the last year. Methods Data are from the Alcohol Research Group's 2000 National Alcohol Survey (n= 7612), which is a computer-assisted telephone interview survey of the U.S. general population 18 and over in all 50 U.S. states and the District of Columbia. Results Sensitivity of the RAPS4 (0.86) was better than the CAGE (0.67) given similar specificity (0.95 vs. 0.98) and outperformed the CAGE for alcohol dependence across all gender, ethnic, and service utilization groups, except among blacks and Hispanics. The RAPS4 also performed equally well for females and males (0.88 vs. 0.85), whereas sensitivity of the CAGE was lower for females. Although sensitivity of the RAPS4 was better than the CAGE for alcohol abuse, sensitivity was low for both (0.56 and 0.36, respectively). When quantity-frequency (QF) questions (drinking five or more drinks on at least one occasion during the last year and drinking as often as once a month during the last year) were added to the RAPS4, the RAPS4-QF performed significantly better for alcohol abuse and outperformed the CAGE at a cut point of one across all gender, ethnic, and service utilization groups. The RAPS4-QF appeared to be most sensitive for alcohol abuse among both males and females reporting emergency room use (0.90). Conclusions The data suggest that the RAPS4 outperforms the CAGE in this general population sample. The addition of a QF question to the RAPS4 improves performance in relation to sensitivity for alcohol abuse, and the RAPS4 and RAPS4-QF may be the instruments of choice in brief screening for alcohol use disorders. Additional research is needed to further explore these issues. [source] Coronary Flow Reserve by Transthoracic Echocardiography Predicts Epicardial Intimal Thickening in Cardiac Allograft VasculopathyAMERICAN JOURNAL OF TRANSPLANTATION, Issue 7 2010F. Tona Cardiac allograft vasculopathy (CAV) is the leading cause of morbidity and mortality in heart transplantation (HT). We sought to investigate the role of coronary flow reserve (CFR) by contrast-enhanced transthoracic echocardiography (CE-TTE) in CAV diagnosis. CAV was defined as maximal intimal thickness (MIT) assessed by intravascular ultrasound (IVUS) ,0.5 mm. CFR was assessed in the left anterior descending coronary artery in 22 HT recipients at 6 ± 4 years post-HT. CAV was diagnosed in 10 patients (group A), 12 had normal coronaries (group B). The mean MIT was 0.7 ± 0.1 mm (range 0.03,1.8). MIT was higher in group A (1.16 ± 0.3 mm vs. 0.34 ± 0.07 mm, p < 0.0001). CFR was 3.1 ± 0.8 in all patients and lower in group A (2.5 ± 0.6 vs. 3.7 ± 0.3, p < 0.0001). CFR was inversely related with MIT (r =,0.774, p < 0.0001). A cut point of ,2.9, identified as optimal by receiver operating characteristics analysis was 100% specific and 80% sensitive (PPV = 100%, NPV = 89%, Accuracy = 91%). CFR assessment by CE-TTE is a novel noninvasive diagnostic tool in the detection of CAV defined as MIT ,0.5 mm. CFR by CE-TTE may reduce the need for routine IVUS in HT. [source] Coronary Flow Reserve by Contrast-Enhanced Echocardiography: A New Noninvasive Diagnostic Tool for Cardiac Allograft VasculopathyAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5p1 2006F. Tona Noninvasive tests have proven unsatisfactory in cardiac allograft vasculopathy (CAV) diagnosis. We assessed coronary flow reserve (CFR) by contrast-enhanced transthoracic echocardiography (CE-TTE) in heart transplantation (HT). CFR was assessed in the left anterior descending coronary artery in 73 HT recipients (59 male, aged 50 ± 12 years at HT), at 8 ± 4.5 years post-HT. CFR measurements were taken blindly from coronary angiographies. CFR cut points were the standard value of ,2 and those defined by receiver operating characteristics (ROC) curve analysis. CFR was lower in patients with CAV (2.3 ± 0.7 vs. 3.2 ± 0.5, p < 0.0001). The ,2 cut point was 100% specific and 38% sensitive. The ,2.7 cut point, optimal by ROC analysis, was 87% specific and 82% sensitive. Accuracy rose from 71% with the standard ,2 cut point to 85% with the optimal cut point of ,2.7. CFR by CE-TTE may offer promise as a novel, easily repeatable and accurate noninvasive tool in CAV detection. However, further longitudinal studies in larger patient cohorts are warranted before widespread adoption can be advocated. [source] Separation of product associating E. coli host cell proteins OppA and DppA from recombinant apolipoprotein A-IMilano in an industrial HIC unit operationBIOTECHNOLOGY PROGRESS, Issue 2 2009Alan K. Hunter Abstract We have shown how product associating E. coli host cell proteins (HCPs) OppA and DppA can be substantially separated from apolipoprotein A-IMilano (apo A-IM) using Butyl Sepharose hydrophobic interaction chromatography (HIC). This work illustrates the complex problems that frequently arise during development and scale-up of biopharmaceutical manufacturing processes. Product association of the HCPs is confirmed using co-immunoprecipitation and Western blotting techniques. Two-dimensional gel electrophoresis and mass spectrometry techniques are used to confirm the identity of OppA and DppA. In this example, clearance of these difficult to separate HCPs decreased significantly when the process was scaled to a 1.4 m diameter column. Laboratory-scale experimentation and trouble shooting identified several key parameters that could be further optimized to improve HCP clearance. The key parameters included resin loading, peak cut point on the ascending side, wash volume, and wash salt concentration. By implementing all of the process improvements that were identified, it was possible to obtain adequate HCP clearance so as to meet the final specification. Although it remains speculative, it is believed that viscosity effects may have contributed to the lower HCP clearance observed early in the manufacturing campaign. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Cumulative Dose of Hypertension Predicts Outcome in Intracranial Hemorrhage Better Than American Heart Association GuidelinesACADEMIC EMERGENCY MEDICINE, Issue 8 2007Christopher W. Barton MD BackgroundHypertension is common after intracranial hemorrhage (ICH) and may be associated with higher mortality and adverse neurologic outcome. The American Heart Association recommends that blood pressure be maintained at a mean arterial pressure (MAP) less than 130 mm Hg to prevent secondary brain injury. ObjectivesTo prospectively evaluate whether a new method of assessing hypertension in ICH more accurately identifies patients at risk for adverse outcomes. MethodsThe authors prospectively studied all patients presenting to two University of California, San Francisco hospitals with acute ICH from June 1, 2001, to May 31, 2004. Factors related to acute hospitalization were recorded in a database, including all charted vital signs for the first 15 days. Patients were followed up for one year, with their modified Rankin Scale (mRS) score at 12 months as primary outcome. Hypertension dose was determined as the area under the curve between patient MAP and a cut point of 110 mm Hg while in the emergency department (ED). The dose was adjusted for time spent in the ED (dose/timeed [d/ted]). Hypertension dose was divided into four categories (none, and progressive tertiles). Multivariate logistic regression was used to calculate the odds ratio for adverse mRS by tertiles of d/ted. ResultsA total of 237 subjects with an ED average (±SD) length of stay of 3.42 (±3.7) hours were enrolled. In a multivariate logistic regression model controlling for the effects of age, volume of hemorrhage, presence of intraventricular hemorrhage, race, and preexisting hypertension, there was a 4.7- and 6.1-fold greater likelihood of an adverse neurologic outcome (by mRS) at one and 12 months, respectively, in the highest d/ted tertile relative to the referent group without hypertension. ConclusionsHypertension after acute ICH is associated with adverse neurologic outcome. The dose of hypertension may more accurately identify patients at risk for adverse outcomes than the American Heart Association guidelines and may lead to better outcomes if treated when identified in this manner. [source] Development of a Brief Mental Health Screen for Intimate Partner Violence Victims in the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 3 2007Debra Houry MD Background: Emergency physicians routinely treat victims of intimate partner violence (IPV) and patients with mental health symptoms, although these issues may be missed without routine screening. In addition, research has demonstrated a strong association between IPV victimization and mental health symptoms. Objectives: To develop a brief mental health screen that could be used feasibly in an emergency department to screen IPV victims for depressive symptoms, posttraumatic stress disorder (PTSD) symptoms, and suicidal ideation. Methods: The authors conducted a pretest/posttest validation study of female IPV victims to determine what questions from the Beck Depression Inventory II, Posttraumatic Stress Diagnostic Scale, and Beck Scale for Suicide Ideation would predict moderate to severe levels of depressive symptoms, PTSD symptoms, and suicidal ideation. A principal components factor analysis was conducted to determine which questions would be used in the brief mental health screen. Scatter plots were then created to determine a cut point. Results: Scores on the brief mental health screen ranged from 0 to 8. A cutoff score of 4 was used, which resulted in positive predictive values of 96% for the brief mental health screen for depression, 84% for PTSD symptoms, and 54% for suicidal ideation. In particular, four questions about sadness, experiencing a traumatic event, the desire to live, and the desire to commit suicide were associated with moderate to severe mental health symptoms in IPV victims. Conclusions: The brief mental health screen provides a tool that could be used in an emergency department setting and predicted those IPV victims with moderate to severe mental health symptoms. Using this tool can assist emergency physicians in recognizing at-risk patients and referring these IPV victims to mental health services. [source] An Independent Evaluation of Four Quantitative Emergency Department Crowding ScalesACADEMIC EMERGENCY MEDICINE, Issue 11 2006Spencer S. Jones MStat Background Emergency department (ED) overcrowding has become a frequent topic of investigation. Despite a significant body of research, there is no standard definition or measurement of ED crowding. Four quantitative scales for ED crowding have been proposed in the literature: the Real-time Emergency Analysis of Demand Indicators (READI), the Emergency Department Work Index (EDWIN), the National Emergency Department Overcrowding Study (NEDOCS) scale, and the Emergency Department Crowding Scale (EDCS). These four scales have yet to be independently evaluated and compared. Objectives The goals of this study were to formally compare four existing quantitative ED crowding scales by measuring their ability to detect instances of perceived ED crowding and to determine whether any of these scales provide a generalizable solution for measuring ED crowding. Methods Data were collected at two-hour intervals over 135 consecutive sampling instances. Physician and nurse agreement was assessed using weighted , statistics. The crowding scales were compared via correlation statistics and their ability to predict perceived instances of ED crowding. Sensitivity, specificity, and positive predictive values were calculated at site-specific cut points and at the recommended thresholds. Results All four of the crowding scales were significantly correlated, but their predictive abilities varied widely. NEDOCS had the highest area under the receiver operating characteristic curve (AROC) (0.92), while EDCS had the lowest (0.64). The recommended thresholds for the crowding scales were rarely exceeded; therefore, the scales were adjusted to site-specific cut points. At a site-specific cut point of 37.19, NEDOCS had the highest sensitivity (0.81), specificity (0.87), and positive predictive value (0.62). Conclusions At the study site, the suggested thresholds of the published crowding scales did not agree with providers' perceptions of ED crowding. Even after adjusting the scales to site-specific thresholds, a relatively low prevalence of ED crowding resulted in unacceptably low positive predictive values for each scale. These results indicate that these crowding scales lack scalability and do not perform as designed in EDs where crowding is not the norm. However, two of the crowding scales, EDWIN and NEDOCS, and one of the READI subscales, bed ratio, yielded good predictive power (AROC >0.80) of perceived ED crowding, suggesting that they could be used effectively after a period of site-specific calibration at EDs where crowding is a frequent occurrence. [source] Identification of second trimester screen positive pregnancies at increased risk for congenital heart defectsPRENATAL DIAGNOSIS, Issue 6 2009Laura L. Jelliffe-Pawlowski Abstract Objective To examine whether second trimester biomarkers could be used to identify screen positive pregnancies at increased risk for congenital heart defects (CHDs) and measure the effect of using different biomarker cut points on the detection of CHDs and on the performance of predictive models. Methods Included were 19,402 pregnancies without chromosomal defects, which were screen positive for Down syndrome or other birth defects based on maternal serum measurements of alpha-fetoprotein (AFP), human chorionic gonadotrophin (hCG), and unconjugated estriol (uE3). Logistic regression models were built that compared biomarkers for CHD cases compared to controls. Results CHD cases were more likely to be screen positive for trisomy-18, to have a nuchal fold (NF) , 5 mm, and/or to have an hCG multiple of the median (MoM) , 95th percentile in models that considered screen positive grouping. In models that did not consider screen positive grouping, cases were more likely to have a NF , 5 mm, an AFP MoM ,10th percentile, an hCG MoM ,25th percentile, and/or an hCG MoM , 75th percentile. Conclusion Along with NF, second trimester maternal serum biomarkers may be useful indicators for fetal and newborn evaluation for CHDs in screen positive pregnancies without identified chromosomal defects. Copyright © 2009 John Wiley & Sons, Ltd. [source] Coronary Flow Reserve by Contrast-Enhanced Echocardiography: A New Noninvasive Diagnostic Tool for Cardiac Allograft VasculopathyAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5p1 2006F. Tona Noninvasive tests have proven unsatisfactory in cardiac allograft vasculopathy (CAV) diagnosis. We assessed coronary flow reserve (CFR) by contrast-enhanced transthoracic echocardiography (CE-TTE) in heart transplantation (HT). CFR was assessed in the left anterior descending coronary artery in 73 HT recipients (59 male, aged 50 ± 12 years at HT), at 8 ± 4.5 years post-HT. CFR measurements were taken blindly from coronary angiographies. CFR cut points were the standard value of ,2 and those defined by receiver operating characteristics (ROC) curve analysis. CFR was lower in patients with CAV (2.3 ± 0.7 vs. 3.2 ± 0.5, p < 0.0001). The ,2 cut point was 100% specific and 38% sensitive. The ,2.7 cut point, optimal by ROC analysis, was 87% specific and 82% sensitive. Accuracy rose from 71% with the standard ,2 cut point to 85% with the optimal cut point of ,2.7. CFR by CE-TTE may offer promise as a novel, easily repeatable and accurate noninvasive tool in CAV detection. However, further longitudinal studies in larger patient cohorts are warranted before widespread adoption can be advocated. [source] Cerebrospinal fluid biomarker signature in Alzheimer's disease neuroimaging initiative subjects,ANNALS OF NEUROLOGY, Issue 4 2009Leslie M. Shaw PhD Objective Develop a cerebrospinal fluid biomarker signature for mild Alzheimer's disease (AD) in Alzheimer's Disease Neuroimaging Initiative (ADNI) subjects. Methods Amyloid-, 1 to 42 peptide (A,1,42), total tau (t-tau), and tau phosphorylated at the threonine 181 were measured in (1) cerebrospinal fluid (CSF) samples obtained during baseline evaluation of 100 mild AD, 196 mild cognitive impairment, and 114 elderly cognitively normal (NC) subjects in ADNI; and (2) independent 56 autopsy-confirmed AD cases and 52 age-matched elderly NCs using a multiplex immunoassay. Detection of an AD CSF profile for t-tau and A,1,42 in ADNI subjects was achieved using receiver operating characteristic cut points and logistic regression models derived from the autopsy-confirmed CSF data. Results CSF A,1,42 was the most sensitive biomarker for AD in the autopsy cohort of CSF samples: receiver operating characteristic area under the curve of 0.913 and sensitivity for AD detection of 96.4%. In the ADNI cohort, a logistic regression model for A,1,42, t-tau, and APO,4 allele count provided the best assessment delineation of mild AD. An AD-like baseline CSF profile for t-tau/A,1,42 was detected in 33 of 37 ADNI mild cognitive impairment subjects who converted to probable AD during the first year of the study. Interpretation The CSF biomarker signature of AD defined by A,1,42 and t-tau in the autopsy-confirmed AD cohort and confirmed in the cohort followed in ADNI for 12 months detects mild AD in a large, multisite, prospective clinical investigation, and this signature appears to predict conversion from mild cognitive impairment to AD. Ann Neurol 2009 [source] The Measurement of the QT and QTc on the Neonatal and Infant Electrocardiogram: A Comprehensive Reliability AssessmentANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2009B.S., Robert M. Gow M.B. Background: An electrocardiogram has been proposed to screen for prolonged QT interval that may predispose infants to sudden death in the first year of life. Understanding the reliability of QT interval measurement will inform the design of a screening program. Methods: Three pediatric cardiologists measured the QT/RR intervals on 60 infant electrocardiograms (median age 46 days), from leads II, V5 and V6 on three separate occasions, 7 days apart, according to a standard protocol. The QTc was corrected by Bazett's (QTcB), Fridericia's (QTCFrid), and Hodges' (QTcH) formulae. Intraobserver and interobserver reliability were assessed by intraclass correlation coefficients (ICC), limits of agreement and repeatability coefficients for single, average of two and average of three measures. Agreement for QTc prolongation (> 440 msec) was assessed by kappa coefficients. Results: QT interval intraobserver ICC was 0.86 and repeatability coefficient was 25.9 msec; interobserver ICC increased from 0.88 for single observations to 0.94 for the average of 3 measurements and repeatability coefficients decreased from 22.5 to 16.7 msec. For QTcB, intraobserver ICC was 0.67, and repeatability was 39.6 msec. Best interobserver reliability for QTcB was for the average of three measurements (ICC 0.83, reproducibility coefficient 25.8 msec), with further improvement for QTcH (ICC 0.92, reproducibility coefficient 16.69 msec). Maximum interobserver kappa for prolonged QTc was 0.77. Misclassification around specific cut points occurs because of the repeatability coefficients. Conclusions: Uncorrected QT measures are more reliable than QTcB and QTCFrid. An average of three independent measures provides the most reliable QT and QTc measurements, with QTcH better than QTcB. [source] Serum levels of vitamin D, sunlight exposure, and knee cartilage loss in older adults: The Tasmanian older adult cohort studyARTHRITIS & RHEUMATISM, Issue 5 2009Changhai Ding Objective To determine the associations between serum levels of vitamin D, sunlight exposure, and knee cartilage loss cross-sectionally and longitudinally in older adults. Methods A total of 880 randomly selected subjects (mean age 61 years [range 51,79 years], 50% women) were studied at baseline, and 353 of these subjects were studied 2.9 years later. Serum levels of 25-hydroxyvitamin D (25[OH]D) were assessed by radioimmunoassay, and sunlight exposure was assessed by questionnaire. T1-weighted fat-suppressed magnetic resonance imaging (MRI) of the right knee was performed to determine knee cartilage volume and defects. Knee radiographic osteoarthritis (OA) and knee pain were also assessed. Results The mean 25(OH)D serum level was 52.8 nmoles/liter at baseline (range 13,119 nmoles/liter). Winter sunlight exposure and serum 25(OH)D level were both positively associated with medial and lateral tibial cartilage volume, and a serum 25(OH)D level <50 nmoles/liter was associated with increased medial tibiofemoral joint space narrowing (all P < 0.05). Longitudinally, baseline serum 25(OH)D level predicted change in both medial and lateral tibial cartilage volume (, = +0.04% per annum per nmole/liter for both; P < 0.05), and change in serum 25(OH)D level was positively associated with change in medial tibial cartilage volume. These associations were consistent in subjects with radiographic OA and knee pain and/or in women, but not in men or in subjects without radiographic OA or knee pain. Conclusion Sunlight exposure and serum 25(OH)D levels are both associated with decreased knee cartilage loss (assessed by radiograph or MRI). This is best observed using the whole range of 25(OH)D levels rather than predefined cut points and implies that achieving vitamin D sufficiency may prevent and/or retard cartilage loss in knee OA. [source] Derivation of a Triage Algorithm for Chest Radiography of Community-acquired Pneumonia Patients in the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 1 2008Demetrios N. Kyriacou MD Abstract Background:, Community-acquired pneumonia (CAP) accounts for 1.5 million emergency department (ED) patient visits in the United States each year. Objectives:, To derive an algorithm for the ED triage setting that facilitates rapid and accurate ordering of chest radiography (CXR) for CAP. Methods:, The authors conducted an ED-based retrospective matched case,control study using 100 radiographic confirmed CAP cases and 100 radiographic confirmed influenzalike illness (ILI) controls. Sensitivities and specificities of characteristics assessed in the triage setting were measured to discriminate CAP from ILI. The authors then used classification tree analysis to derive an algorithm that maximizes sensitivity and specificity for detecting patients with CAP in the ED triage setting. Results:, Temperature greater than 100.4°F (likelihood ratio = 4.39, 95% confidence interval [CI] = 2.04 to 9.45), heart rate greater than 110 beats/minute (likelihood ratio = 3.59, 95% CI = 1.82 to 7.10), and pulse oximetry less than 96% (likelihood ratio = 2.36, 95% CI = 1.32 to 4.20) were the strongest predictors of CAP. However, no single characteristic was adequately sensitive and specific to accurately discriminate CAP from ILI. A three-step algorithm (using optimum cut points for elevated temperature, tachycardia, and hypoxemia on room air pulse oximetry) was derived that is 70.8% sensitive (95% CI = 60.7% to 79.7%) and 79.1% specific (95% CI = 69.3% to 86.9%). Conclusions:, No single characteristic adequately discriminates CAP from ILI, but a derived clinical algorithm may detect most radiographic confirmed CAP patients in the triage setting. Prospective assessment of this algorithm will be needed to determine its effects on the care of ED patients with suspected pneumonia. 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