Interobserver Assessments Research Articles

P2.01-047 Intra- and Inter-Observer Reproducibility Study of PD-L1 Biomarker in Non-Small Cell Lung Cancer (NSCLC) - The DREAM STUDY

PD-L1 expression in NSCLC correlates with increased response to pembrolizumab, supporting its role as a predictive biomarker but the reproducibility of pathologists’ scoring of PD-L1 requires further investigation. The primary objective of the DREAM study was to assess the reproducibility of scoring PD-L1 staining by evaluating intra- and inter-observer reproducibility for the assessment of PD-L1 expression in NSCLC. The secondary objective was to assess the impact of training on reproducibility. The study was a blinded, pathologist reproducibility study of scoring PD-L1 expression in NSCLC cases stained with PD-L1 22C3 pharmDx™ kit using the Dako Automated Link 48 Platform. Two pathologists previously trained and certified by Dako scored 789 specimens to form the gold standard. From these specimens 60 were randomly selected to evaluate a 1% cut-point and 60 for a 50% cut-point. Both sample sets were designed to include 50% positive/negative specimens and 20-30 close to each cut-point. Ten pathologists were randomly assigned to two subgroups. Subgroup 1 analyzed all samples on two consecutive days. Subgroup 2 performed the same assessments, except they received a one hour training session prior to the second assessment. The overall percent agreement (OPA) for the analysis of the intra-observer reproducibility was 89.7% (95% CI: 85.7; 92.6) for the 1% cut-point sample set and 91.3% (95% CI: 87.6; 94.0) for the 50% cut-point. The OPAs for inter-observer reproducibility of all ten pathologists were 84.2% (95% CI: 82.8; 85.5) and 81.9% (95% CI: 80.4; 83.3) for the 1% and 50% cut-point sample sets, respectively. There was substantial agreement at both the 1% cut-point (prevalence-adjusted bias-adjusted kappa 0.68 (95% CI: 0.65; 0.71)) and the 50% cut-point (prevalence-adjusted bias-adjusted kappa 0.64 (95% CI: 0.61; 0.67)). Training was found to have no or very little impact on the inter- or intra-observer reproducibility in subgroup 2. The OPAs for the inter-observer reproducibility assessments were 82.0% and 82.3% for the first and second assessments of the 1% cut-point sample set, respectively, and 78.3% and 81.7% for the first and second assessments of the 50% cut-point sample set, respectively. The exploratory analyses showed that the sensitivity and specificity of the pathologists assessments, compared with the gold standard assessment, were 84.3% and 91.3%, respectively, for the 1% cut-point and 56.3% and 94.0%, respectively, for the 50% cut-point. There is high intra-observer reproducibility and substantial inter-observer agreement in pathologists’ assessment of PD-L1 expression in NSCLC at 1% and 50% cut-points.

P086: Accuracy of the Ottawa Ankle Rules when applied by allied health providers in a pediatric emergency department

Introduction: The Ottawa Ankle Rules (OAR) are a clinical decision tool used to minimize unnecessary radiographs in ankle and foot injuries. The OAR has been shown to be a reliable rule to exclude fractures in children over 5 years of age. However, there is limited data to support its use by other health care workers in children. Our objective was to determine the sensitivity and specificity of the OAR, to detect clinically significant fractures, when applied by allied health providers (AHPs). Methods: Children aged 5 to 17 years presenting with an acute ankle or foot injury were enrolled. Patients assessed by a physician prior to an AHP, presenting for reassessment or >24 hours after the injury, having open, penetrating or neurovascular injury, or multiple injuries were excluded. Patients with metabolic bone disease, a previous x-ray, or the inability to communicate or ambulate before the injury were also excluded. Baseline data on x-ray use was collected in a convenience sample of 100 patients. AHPs then completed an OAR learning module. Then in phase 2, AHPs applied the OAR to a convenience sample of 186 patients. Both AHPs and physicians performed inter-observer assessments. Results: When AHP’s applied the ankle portion of the OAR, the sensitivity was 88% (95% CI 46.7-99.3) and the specificity was 32.5% (95% CI 24.5-41.6) for clinically significant fractures. When AHP’s applied the foot portion of the OAR, the sensitivity was 87.5% (95% CI 46.7-99.3) and the specificity was 15.6% (95% CI 7.0-30.1) for clinically significant fractures. In total, 2 clinically significant fractures (1 foot fracture and 1 ankle fracture) were missed by AHP’s. Inter-observer agreement was κ=0.24 for the ankle rule and κ=0.32 for the foot rule. The missed ankle fracture had a positive OAR when performed by a physician as an inter-observer assessment. The missed foot fracture was a distal metatarsal fracture that was outside of the “foot zone” as defined by the OAR. Conclusion: The sensitivity of the OAR when applied by AHP’s was very good. Both clinically significant fractures that were missed by AHP’s would likely have been picked up by a physician assessment. More training and practice using the OAR would likely improve AHP’s inter-observer reliability. Our data suggest the OAR may be a useful tool for AHP’s to apply as a screening tool prior to physician assessment.

Validación de un programa electrónico de historia clínica que orienta el estudio de la apendicitis aguda en pediatría

AntecedentsThe use of electronic medical record software for the diagnosis of the acute appendicitis has not been reported in our media. ObjectiveTo validate the use of medical record software, designed by the authors, that guides the management of patients with abdominal pain with suspected acute appendicitis. MethodologyA prospective, longitudinal and observational study was performed in the Emergency Service of the Hospital Erasmo Meoz, between 30 May 2013, and May 2014, on patients between 5 and 14 years old, who came to the paediatric emergency department with acute abdominal pain and the general doctor suspected acute appendicitis.Appendicitis was defined as the presence of a positive cytology report. Interobserver assessments were performed, and the sensitivity, specificity and the positive and negative value. ResultsOf 130 patients, 30 were excluded due to faulty inclusion criteria. The calculated kappa coefficient was 0.7 (95% confidence interval: 0.43-0.76). The cut-off points with the highest sensitivity were 1 and 2 (98.63% [95% CI; 92.6-99.7]), but with a specificity of 0% (95% CI; 0.0-12.4). The highest specificity was found between 9 and 10 (100% [95% CI; 43.8 - 100])), being the same for the lowest sensitivity (4.11% [CI 95%1.4-11.4]). By historic report, 100% of the operated patients had acute appendicitis. ConclusionsThe development of the electronic medical record software provides a valuable tool in the diagnostic process of a patient with pain, as it classifies patients with and without appendicitis.

Evaluation of a Web-Based Food Record for Children Using Direct Unobtrusive Lunch Observations: A Validation Study.

BackgroundHigh-quality, Web-based dietary assessment tools for children are needed to reduce cost and improve user-friendliness when studying children’s dietary practices.ObjectiveTo evaluate the first Web-based dietary assessment tool for children in Norway, the Web-based Food Record (WebFR), by comparing children’s true school lunch intake with recordings in the WebFR, using direct unobtrusive observation as the reference method.MethodsA total of 117 children, 8-9 years, from Bærum, Norway, were recruited from September to December 2013. Children completed 4 days of recordings in the WebFR, with parental assistance, and were observed during school lunch in the same period by 3 observers. Interobserver reliability assessments were satisfactory. Match, omission, and intrusion rates were calculated to assess the quality of the recordings in the WebFR for different food categories, and for all foods combined. Logistic regression analyses were used to investigate whether body mass index (BMI), parental educational level, parental ethnicity or family structure were associated with having a “low match rate” (≤70%).ResultsBread and milk were recorded with less bias than spreads, fruits, and vegetables. Mean (SD) for match, omission, and intrusion rates for all foods combined were 73% (27%), 27% (27%), and 19% (26%), respectively. Match rates were statistically significantly associated with parental educational level (low education 52% [32%] versus high 77% [24%], P=.008) and parental ethnicity (non-Norwegian 57% [28%] versus others 75% [26%], P=.04). Only parental ethnicity remained statistically significant in the logistic regression model, showing an adjusted odds ratio of 6.9 and a 95% confidence interval between 1.3 and 36.4.ConclusionsCompared with other similar studies, our results indicate that the WebFR is in line with, or better than most of other similar tools, yet enhancements could further improve the WebFR.

Evaluation of cephalometric landmark identification on CBCT multiplanar and 3D reconstructions

To evaluate the reliability of three-dimensional (3D) landmark identification in cone-beam computed tomography (CBCT) using two different visualization techniques. Twelve CBCT images were randomly selected. Three observers independently repeated three times the identification of 30 landmarks using 3D reconstructions and 28 landmarks using multiplanar views. The values of the coordinates X, Y, and Z of each point were obtained and the intraclass correlation coefficient (ICC) was calculated. The ICC of the 3D visualization was rated >0.90 in 67.76% and 45.56%, and ≤0.45 in 13.33% and 14.46% of the intraobserver and interobserver assessments, respectively. The ICC of the multiplanar visualization was rated >0.90 in 82.16% and 78.56% and ≤0.45 in only 16.7% and 8.33% of the intraobserver and interobserver assessments, respectively. An individual landmark classification was done according to ICC values. The frequency of highly reliable values was greater for multiplanar than 3D reconstructions. Overall, lower reliability was found for points on the condyle and higher reliability for those on the midsagittal plane. Depending on the anatomic region, the observer must choose the most reliable type of image visualization.

Development of a Standard Protocol for the Harmonic Analysis of Radial Pulse Wave and Assessing Its Reliability in Healthy Humans.

This study was aimed to establish a standard protocol and to quantitatively assess the reliability of harmonic analysis of the radial pulse wave measured by a harmonic wave analyzer (TD01C system). Both intraobserver and interobserver assessments were conducted to investigate whether the values of harmonics are stable in successive measurements. An intraclass correlation coefficient (ICC) and a Bland–Altman plot were used for this purpose. For the reliability assessments of the intraobserver and the interobserver, 22 subjects (mean age 45 ± 14 years; 14 males and 8 females) were enrolled. The first eleven harmonics of the radial pulse wave presented excellent repeatability (n}{}text {ICCs}>0.9n and n}{}text {p}<0.001n) for the intraobserver assessment and high reproducibility (ICCs range from 0.83 to 0.96 and n}{}text {p}<0.001n) for the interobserver assessment. The Bland–Altman plot indicated that more than 90% of harmonic values fell within two standard deviations of the mean difference. Thus, we concluded that the harmonic analysis of the radial pulse wave using the TD01C system is a feasible and reliable method to assess a hemodynamic characteristic in clinical trial.

Abstract 4961: Longitudinal bioluminescence imaging of primary versus abdominal metastatic tumor growth in orthotopic pancreatic tumor models in NOD/SCIDγ(-/-) mice

Abstract Pancreatic ductal adenocarcinoma (PDAC) has a very poor prognosis and is currently the fourth leading cause of cancer death in the United States. The lethal nature of PDAC is strongly associated with metastases to distant organs. The purpose of the present study was to develop and validate noninvasive bioluminescence imaging methods for differentially monitoring the kinetics of primary and abdominal metastatic tumor growth in mouse orthotopic models of pancreatic cancer. A semiautomated maximum entropy segmentation method was implemented for the primary tumor region-of-interest (ROI), and a rule-based method for manually drawing an ROI for the abdominal metastatic region also was developed. The two ROI methods were first validated by having two observers independently construct ROIs for the tumors of animals implanted orthotopically with Panc-1 cells, and the results compared with the number of mesenteric lymph node metastatic nodules counted upon necropsy. The findings were extended to orthotopic tumors of the more metastatic MIA PaCa-2 and AsPC-1 cells where different groups of animals were implanted with different numbers of cells. When the data were expressed as the total photon flux (Ph/sec) in the ROIs for the primary tumor and metastases, the total flux within the metastasis ROI was larger in magnitude than the total flux from the primary tumor ROI, at times by as much as several orders of magnitude. However, when the data were expressed as the average flux density (Ph/sec*mm2) within the ROIs, the density of the flux within the smaller primary tumor ROI was larger in magnitude than the density of the flux from the larger metastasis ROI, by as much as several orders of magnitude. Interobserver assessments for total flux and flux density from ROIs for both the primary tumors and metastatic region were highly concordant, with correlation coefficients of r &amp;gt; 0.98, coefficients of variation of ≤ 0.02, and limits of agreement within &amp;lt;5%. Further, there were statistically significant differences in the growth kinetics of AsPC-1 and MIA PaCa-2 orthotopic tumors when mice were implanted with different numbers of cells for each cell line. The present results demonstrated that the segmentation methods were highly reliable, reproducible and robust, and allowed statistically significant discrimination in the growth kinetics of primary and abdominal metastatic tumors of different cell lines implanted with different cell numbers. Thus, primary tumors and abdominal metastatic foci in orthotopic pancreatic cancer models can be reliably monitored separately and noninvasively over time with bioluminescence imaging. The novel segmentation methods reported here will facilitate investigations of the biology of primary and metastatic tumor growth, as well as the effects of novel treatments, over time, in individual animals. Citation Format: Harlan E. Shannon, Melissa L. Fishel, Jingwu Xie, Dongsheng Gu, Brian P. McCarthy, Amanda A. Riley, Anthony L. Sinn, Jayne M. Silver, Mark R. Kelley, Helmut Hanenberg, Murray Korc, Karen E. Pollok, Paul R. Territo. Longitudinal bioluminescence imaging of primary versus abdominal metastatic tumor growth in orthotopic pancreatic tumor models in NOD/SCIDγ(-/-) mice. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4961. doi:10.1158/1538-7445.AM2014-4961

Vaginal microcirculation: Non-invasive anatomical examination of the micro-vessel architecture, tortuosity and capillary density.

To describe the vaginal microcirculatory architecture and capillary density parameters using sidestream dark-field imaging (SDFI), and determine feasibility and reliability of this method. In nine healthy female volunteers SDFI measurements were performed at two different time points in the luteal phase of the menstrual cycle. Non-invasive tissue micro-angioarchitecture and vaginal capillary density measurements were assessed independently by two observers. Agreement was expressed with mean differences between the measurements of both observers and the limits of agreement. Inter- and intra-observer agreement was quantified with the intra-class correlation coefficient (ICC). Vaginal microcirculatory assessment with the SDFI device was easy in use, painless and well accepted by the participants. Morphologically, the vaginal microcirculation revealed an array of single hairpin-shaped capillary loops distributed homogeneously across an imaged tissue segment. The intra-observer assessment of the capillary density measurements (comparing two measurement time points of one observer) showed good agreement with an ICC ranging from 0.62 to 0.85. The inter-observer assessments of the capillary density measurements (comparing assessments of two observers at one time point) revealed very good agreement, with small differences between observers and an ICC of more than 0.9. This is the first report on both microcirculatory architecture and quantitative microcirculatory parameters of the vagina with the use of SDFI. Micro-vessels of the vagina show a recognizable pattern in our study population of young, healthy women. SDFI gives a reproducible assessment of the vaginal microcirculation offering the researcher a wide field of applications.

The use of the lumbosacral enlargement as an intrinsic imaging biomarker: feasibility of grey matter and white matter cross-sectional area measurements using MRI at 3T.

Histopathological studies have demonstrated the involvement of spinal cord grey matter (GM) and white matter (WM) in several diseases and recent research has suggested the use of magnetic resonance imaging (MRI) as a promising tool for in vivo assessment of the upper spinal cord. However, many neurological conditions would benefit from quantitative assessment of tissue integrity at different levels and relatively little work has been done, mainly due to technical challenges associated with imaging the lower spinal cord. In this study, the value of the lumbosacral enlargement (LSE) as an intrinsic imaging biomarker was determined by exploring the feasibility of obtaining within it reliable GM and WM cross-sectional area (CSA) measurements by means of a commercially available MRI system at 3 tesla (T). 10 healthy volunteers (mean age 27.5 years, 6 female) gave written informed consent and high resolution images of the LSE were acquired and analysed using an optimised MRI acquisition and analysis protocol. GM and WM mean CSA measurements were obtained from a 15 mm section at the level of the LSE and the reproducibility of the measurements was determined by means of scan-rescan, intra- and inter-observer assessments. Mean (±SD) LSE cross-sectional area (LSE-CSA) was 62.3 (±4.1) mm2 and mean (±SD) LSE grey matter cross-sectional area (LSE-GM-CSA) was 19.8 (±3.3) mm2. The mean scan-rescan, intra- and inter-observer % coefficient of variation (COV) for measuring the LSE-CSA were 2%, 2% and 2.5%, respectively and for measuring the LSE-GM-CSA were 7.8%, 8% and 8.6%, respectively. This study has shown that the LSE can be used reliably as an intrinsic imaging biomarker. The method presented here can be potentially extended to study the LSE in the diseased state and could provide a solid foundation for subsequent multi-parametric MRI investigations.

USING MODIFIED VISUAL‐INSPECTION CRITERIA TO INTERPRET FUNCTIONAL ANALYSIS OUTCOMES

The development of functional analysis (FA) methodologies allows the identification of the reinforcers that maintain problem behavior and improved intervention efficacy in the form of function-based treatments. Despite the profound impact of FA on clinical practice and research, questions still remain about the methods by which clinicians and researchers interpret FA graphs. In the current study, 141 FA data sets were evaluated using the structured visual-inspection criteria developed by Hagopian et al. (1997). However, the criteria were modified for FAs of varying lengths. Interobserver agreement assessments revealed high agreement coefficients across expert judges, postdoctoral reviewers, master's-level reviewers, and postbaccalaureate reviewers. Once the validity of the modified visual-inspection procedures was established, the utility of those procedures was examined by using them to categorize the maintaining reinforcement contingency related to problem behavior for all 141 data sets and for the 101 participants who contributed to the 141 data sets.

Clinical Decision Rules to Improve the Detection of Adverse Drug Events in Emergency Department Patients

Adverse drug events (ADEs) are unintended and harmful consequences of medication use. They are associated with high health resource use and cost. Yet, high levels of inaccuracy exist in their identification in clinical practice, with over one-third remaining unidentified in the emergency department (ED). The study objective was to derive clinical decision rules (CDRs) that are sensitive for the detection of ADEs, allowing their systematic identification early in a patient's hospital course. This was a prospective observational cohort study carried out in two Canadian tertiary care hospitals. Participants were adults presenting to the ED having ingested at least one prescription or over-the-counter medication within 2 weeks. Nurses and physicians evaluated patients for standardized clinical findings. A second evaluator performed interobserver assessments of predictor variables in a subset of patients. Pharmacists, who were blinded to the predictor variables, evaluated all patients for ADEs. An independent committee reviewed and adjudicated cases where the ADE assessment was uncertain or the pharmacist's diagnosis differed from the physician's working diagnosis. The primary outcome was an ADE that required a change in medical therapy, diagnostic testing, consultation, or hospital admission. CDRs were derived using kappa coefficients, chi-square statistics, and recursive partitioning. Among 1,591 patients, 131 (8.2%, 95% confidence interval [CI] = 7.0% to 9.7%) were diagnosed with the primary outcome. The following variables were associated with ADEs and were used to derive two CDRs: 1) presence of comorbid conditions, 2) antibiotic use within 7 days, 3) medication changes within 28 days, 4) age ≥ 80 years, 5) arrival by ambulance, 6) triage acuity, 7) recent hospital admission, 8) renal failure, and 9) use of three or more prescription medications. The more sensitive rule had a sensitivity of 96.7% (95% CI = 91.8% to 98.6%) and required 40.8% (95% CI = 37.7% to 42.9%) of patients to have medication review. The more specific rule had a sensitivity 90.8% (95% CI = 81.4% to 95.7%) and required 28.3% of patients to proceed to medication review. The authors derived CDRs that identified patients with ADEs with high sensitivity. These rules may improve the identification of ADEs early in a patient's hospital course while limiting the number of patients requiring a detailed medication review.

Hip Range of Motion in Children

Abnormal range of motion (ROM) is a common sign of pathology in the pediatric hip, yet there are little data in the literature defining what the normal hip ROM is in children. The purpose of this study was to establish normative values for hip ROM in children of varying ages. We performed an Institutional Review Board approved, prospective study of otherwise healthy patients receiving fracture care at our institution. Inclusion criteria were boys and girls aged 2 to 17, who were being treated for an isolated upper extremity injury and who had no underlying musculoskeletal condition, history of lower extremity injury, or other systemic diagnosis. All patients were evaluated with a standard measurement technique using the same double-long-armed goniometer. Supine abduction, adduction, and hip flexion were measured with care taken to stabilize the pelvis. Internal and external rotation in flexion were assessed with both the hip and knee flexed to 90 degrees. In the prone position, hip extension was recorded as was internal and external rotation in extension. Left and right measurements were averaged to produce a single data point for each index. On the basis of a power analysis (to detect a minimal detectable difference of 6 degrees), 2 separate cohorts of 23 patients were randomly selected for the assessment of intraobserver and interobserver reliability. We measured 504 hips in 252 pediatric patients, including 163 boys and 89 girls. We found a decreasing trend in ROM for almost all indices with advancing age, although this decline was less apparent among girls. Intraobserver reliability demonstrated excellent agreement (intra class correlation coefficient>0.81) for all indices. Interobserver assessments revealed excellent agreement for abduction, external rotation in flexion, internal rotation in extension, and external rotation in extension. Substantial agreement (intra class correlation coefficient, 0.61 to 0.8) was found for adduction, flexion, extension, and internal rotation in flexion. Normative values for hip ROM in children of varying ages have been established with acceptable intraobserver and interobserver reliability. Level II (Diagnostic).

10 Clinical Decision Rules to Improve the Detection of Adverse Drug Events in Emergency Department Patients

10 Clinical Decision Rules to Improve the Detection of Adverse Drug Events in Emergency Department Patients

544 COMPARING THE VALIDITY AND REPRODUCIBILITY OF THREE RENAL TUMOR SCORING SYSTEMS: C-INDEX VS P.A.D.U.A. VS R.E.N.A.L.

INTRODUCTION AND OBJECTIVES: C–INDEX, P.A.D.U.A., and R.E.N.A.L. Nephrometry were proposed as standardized scoring systems (SS) to quantify anatomical elements of kidney tumors. The objective of this study was to compare reproducibility and validity of these SS. METHODS: Interobserver reliability was assessed in 50 subjects by weighted kappa. Two residents and one fellow reviewed this subset of patients. Predictive validity was assessed in 100 patients reviewed by one fellow, using Spearman correlations to examine relationships between SS and variables of interest. RESULTS: The interobserver correlations for the C-Index was 0.84 and for P.A.D.U.A. was 0.81, for R.E.N.A.L. was 0.92 demonstrating excellent reliability. The correlations between the three tumor rating systems were: C-Index and P.A.D.U.A. p 0.0001; C-Index and R.E.N.A.L. p 0.0001; P.A.D.U.A. and R.E.N.A.L. p 0.0001. Correlations with actual tumor size were significant for each of the SS (C-Index p 0.0001; P.A.D.U.A. p 0.0002; R.E.N.A.L. p 0.006). There were no significant correlations with any of the SS and the presence of intraoperative and postoperative complications, operative time or blood loss. There were no significant correlations with length of hospitalization for P.A.D.U.A. or R.E.N.A.L. However, longer hospital stay was significantly associated with lower C-Index scores (p 0.04). All three SS were significantly correlated with duration of warm ischemia (C-Index p 0.0001; P.A.D.U.A. p 0.02; R.E.N.A.L. p 0.001) and % change in creatinine comparing preoperative to postoperative laboratory assessment (C-Index p 0.0009; P.A.D.U.A. p 0.0003; R.E.N.A.L. p 0.001). CONCLUSIONS: All three scoring systems represent novel methods of quantitative describing renal tumors in a standardized manner with reproducible interobserver assessments. All SS analyzed were predictors of warm ischemia time, % change in creatinine, and tumor size. They did not, however, correlate with any other perioperative parameters investigated. At this time, these SS provide a common language for describing renal tumors but their prognostic value is yet to be fully elucidated.

Multicentre prospective validation of use of the Canadian C-Spine Rule by triage nurses in the emergency department

The Canadian C-Spine Rule for imaging of the cervical spine was developed for use by physicians. We believe that nurses in the emergency department could use this rule to clinically clear the cervical spine. We prospectively evaluated the accuracy, reliability and acceptability of the Canadian C-Spine Rule when used by nurses. We conducted this three-year prospective cohort study in six Canadian emergency departments. The study involved adult trauma patients who were alert and whose condition was stable. We provided two hours of training to 191 triage nurses. The nurses then assessed patients using the Canadian C-Spine Rule, including determination of neck tenderness and range of motion, reapplied immobilization and completed a data form. Of the 3633 study patients, 42 (1.2%) had clinically important injuries of the cervical spine. The kappa value for interobserver assessments of 498 patients with the Canadian C-Spine Rule was 0.78. We calculated sensitivity of 100.0% (95% confidence interval [CI] 91.0%-100.0%) and specificity of 43.4% (95% CI 42.0%-45.0%) for the Canadian C-Spine Rule as interpreted by the investigators. The nurses classified patients with a sensitivity of 90.2% (95% CI 76.0%-95.0%) and a specificity of 43.9% (95% CI 42.0%-46.0%). Early in the study, nurses failed to identify four cases of injury, despite the presence of clear high-risk factors. None of these patients suffered sequelae, and after retraining there were no further missed cases. We estimated that for 40.7% of patients, the cervical spine could be cleared clinically by nurses. Nurses reported discomfort in applying the Canadian C-Spine Rule in only 4.8% of cases. Use of the Canadian C-Spine Rule by nurses was accurate, reliable and clinically acceptable. Widespread implementation by nurses throughout Canada and elsewhere would diminish patient discomfort and improve patient flow in overcrowded emergency departments.

Prospective Validation of the Pediatric Appendicitis Score in a Canadian Pediatric Emergency Department

Clinical scoring systems attempt to improve the diagnostic accuracy of pediatric appendicitis. The Pediatric Appendicitis Score (PAS) was the first score created specifically for children and showed excellent performance in the derivation study when administered by pediatric surgeons. The objective was to validate the score in a nonreferred population by emergency physicians (EPs). A convenience sample of children, 4-18 years old presenting to a pediatric emergency department (ED) with abdominal pain of less than 3 days' duration and in whom the treating physician suspected appendicitis, was prospectively evaluated. Children who were nonverbal, had a previous appendectomy, or had chronic abdominal pathology were excluded. Score components (right lower quadrant and hop tenderness, anorexia, pyrexia, emesis, pain migration, leukocytosis, and neutrophilia) were collected on standardized forms by EPs who were blinded to the scoring system. Interobserver assessments were completed when possible. Appendicitis was defined as appendectomy with positive histology. Outcomes were ascertained by review of the pathology reports from the surgery specimens for children undergoing surgery and by telephone follow-up for children who were discharged home. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) were calculated. The overall performance of the score was assessed by a receiver operator characteristic (ROC) curve. Of the enrolled children who met inclusion criteria (n = 246), 83 (34%) had pathology-proven appendicitis. Using the single cut-point suggested in the derivation study (PAS 5) resulted in an unacceptably high number of false positives (37.6%). The score's performance improved when two cut-points were used. When children with a PAS of <or=4 were discharged home without further investigations, the sensitivity was 97.6% with a NPV of 97.7%. When a PAS of >or=8 determined the need for appendectomy, the score's specificity was 95.1% with a PPV of 85.2%. Using this strategy, the negative appendectomy rate would have been 8.8%, the missed appendicitis rate would have been 2.4%, and 41% of imaging investigations would have been avoided. The PAS is a useful tool in the evaluation of children with possible appendicitis. Scores of <or=4 help rule out appendicitis, while scores of >or=8 help predict appendicitis. Patients with a PAS of 5-7 may need further radiologic evaluation.

Harmonization process and reliability assessment of anthropometric measurements in a multicenter study in adolescents

To describe the standardization process and reliability of anthropometric and bioelectrical impedance analysis (BIA) measurements. We examined both intra- and interobserver errors for skinfolds, circumferences and BIA. For the intraobserver error assessment, first of all, 202 adolescents in the pilot study (110 boys, 92 girls, aged 13.64+/-0.78 years) were assessed. For the second intraobserver and interobserver assessments, 10 adolescents were studied (5 boys and 5 girls). The pilot study's intraobserver technical errors of measurement (TEMs) were between 0.12 and 2.9 mm for skinfold thicknesses, and between 0.13 and 1.75 cm for circumferences. Intraobserver reliability for skinfold thicknesses was greater than 69.44% and beyond 78.43% for circumferences. The final workshop's intraobserver TEMs for skinfold thicknesses and circumferences were smaller than 1; for BIA resistance TEMs were smaller than 0.1 Omega and for reactance they were smaller than 0.2 Omega. Intraobserver reliability values were greater than 95, 97, 99 and 97% for skinfold thicknesses, circumferences, BIA resistance and reactance, respectively. Interobserver TEMs for skinfold thicknesses and circumferences ranged from 1 to 2 mm; for BIA they were 1.16 and 1.26 Omega for resistance and reactance, respectively. Interobserver reliability for skinfold thicknesses and circumferences were greater than 90%, and for BIA resistance and reactance they were greater than 90%. After the results of the pilot study, it was necessary to optimize the quality of the anthropometric measurements before the final survey. Significant improvements were observed in the intraobserver reliabilities for all measurements, with interobserver reliabilities being higher than 90% for most of the measurements.The Healthy Lifestyle in Europe by Nutrition in Adolescence Study aims to describe total body fat percentage and anthropometric indices of body fat distribution in European adolescents.

Observer reliability of three-dimensional cephalometric landmark identification on cone-beam computerized tomography

To evaluate reliability in 3-dimensional (3D) landmark identification using cone-beam computerized tomography (CBCT). Twelve presurgery CBCTs were randomly selected from 159 orthognathic surgery patients. Three observers independently repeated 3 times the identification of 30 landmarks in the sagittal, coronal, and axial slices. A mixed-effects analysis of variance model estimated the intraclass correlations (ICC) and assessed systematic bias. The ICC was >0.9 for 86% of intraobserver assessments and 66% of interobserver assessments. Only 1% of intraobserver and 3% of interobserver coefficients were <0.45. The systematic difference among observers was greater in X and Z than in Y dimensions, but the maximum mean difference was quite small. Overall, the intra- and interobserver reliability was excellent. Three-dimensional landmark identification using CBCT can offer consistent and reproducible data if a protocol for operator training and calibration is followed. This is particularly important for landmarks not easily specified in all 3 planes of space.

Comparison of the reproducibility of quantitative cardiac left ventricular assessments in healthy volunteers using different MRI scanners: A multicenter simulation

To derive reproducibility assessments of ejection fraction (EF) and left ventricular mass (LVM) from short-axis cardiac MR images acquired at single and multiple time-points on different 1.5T scanner models. Images of 15 healthy volunteers were acquired twice using a Magnetom Avanto scanner (Siemens, Erlangen, Germany) and once using a Signa Excite scanner (General Electric, Milwaukee, WI, USA) over four months, and analyzed using ARGUS and MASS Analysis+ software, respectively. Two physicists independently segmented the myocardial borders in order to derive intra- and interobserver assessments of EF and LVM for single and multiple time-points on the same and different scanners. For EF, the coefficient of repeatability (CoR) increased as different observers, multiple time-points, and different scanners were introduced. The CoR ranged from 2.8% (intraobserver measurements, single time-point, same scanner) to 10.0% (interobserver measurements, different time-points, different scanners). For LVM, intraobserver CoR parameters were consistently smaller than interobserver values. The CoR ranged from 7.8 g (intraobserver measurements, single time-point, same scanner) to 39.5 g (interobserver measurements, different time-points, different scanners). Reproducible EF data can be obtained at single or multiple time-points using different scanners. However, LVM is notably susceptible to interobserver variation, and this should be carefully considered if similar evaluations are planned as part of multicenter or longitudinal investigations.

Assessing normal pulse wave velocity in the proximal pulmonary arteries using transit time: A feasibility, repeatability, and observer reproducibility study by cardiovascular magnetic resonance

To calculate pulse wave velocity (PWV) in the proximal pulmonary arteries (PAs) by cardiovascular magnetic resonance (CMR) using the transit-time method, and address respiratory variation, repeatability, and observer reproducibility. A 1.9-msec interleaved phase velocity sequence was repeated three times consecutively in 10 normal subjects. Pulse wave (PW) arrival times (ATs) were determined for the main and branch PAs. The PWV was calculated by dividing the path length traveled by the difference in ATs. Respiratory variation was considered by comparing acquisitions with and without respiratory gating. For navigated data the mean PWVs for the left PA (LPA) and right PA (RPA) were 2.09 +/- 0.64 m/second and 2.33 +/- 0.44 m/second, respectively. For non-navigated data the mean PWVs for the LPA and RPA were 2.14 +/- 0.41 m/second and 2.31 +/- 0.49 m/second, respectively. No statistically significant difference was found between respiratory non-navigated data and navigated data. Repeated on-table measurements were consistent (LPA non-navigated P = 0.95, RPA non-navigated P = 0.91, LPA navigated P = 0.96, RPA navigated P = 0.51). The coefficients of variation (CVs) were 12.2% and 12.5% for intra- and interobserver assessments, respectively. One can measure PWV in the proximal PAs using transit-time in a reproducible manner without respiratory gating.