Development and validation of a registry-based definition of eosinophilic esophagitis in Denmark

PubMed Central

Dellon, Evan S; Erichsen, Rune; Pedersen, Lars; Shaheen, Nicholas J; Baron, John A; Sørensen, Henrik T; Vyberg, Mogens

2013-01-01

AIM: To develop and validate a case definition of eosinophilic esophagitis (EoE) in the linked Danish health registries. METHODS: For case definition development, we queried the Danish medical registries from 2006-2007 to identify candidate cases of EoE in Northern Denmark. All International Classification of Diseases-10 (ICD-10) and prescription codes were obtained, and archived pathology slides were obtained and re-reviewed to determine case status. We used an iterative process to select inclusion/exclusion codes, refine the case definition, and optimize sensitivity and specificity. We then re-queried the registries from 2008-2009 to yield a validation set. The case definition algorithm was applied, and sensitivity and specificity were calculated. RESULTS: Of the 51 and 49 candidate cases identified in both the development and validation sets, 21 and 24 had EoE, respectively. Characteristics of EoE cases in the development set [mean age 35 years; 76% male; 86% dysphagia; 103 eosinophils per high-power field (eos/hpf)] were similar to those in the validation set (mean age 42 years; 83% male; 67% dysphagia; 77 eos/hpf). Re-review of archived slides confirmed that the pathology coding for esophageal eosinophilia was correct in greater than 90% of cases. Two registry-based case algorithms based on pathology, ICD-10, and pharmacy codes were successfully generated in the development set, one that was sensitive (90%) and one that was specific (97%). When these algorithms were applied to the validation set, they remained sensitive (88%) and specific (96%). CONCLUSION: Two registry-based definitions, one highly sensitive and one highly specific, were developed and validated for the linked Danish national health databases, making future population-based studies feasible. PMID:23382628

Development and validation of an epidemiologic case definition of epilepsy for use with routinely collected Australian health data.

PubMed

Tan, Michael; Wilson, Ian; Braganza, Vanessa; Ignatiadis, Sophia; Boston, Ray; Sundararajan, Vijaya; Cook, Mark J; D'Souza, Wendyl J

2015-10-01

We report the diagnostic validity of a selection algorithm for identifying epilepsy cases. Retrospective validation study of International Classification of Diseases 10th Revision Australian Modification (ICD-10AM)-coded hospital records and pharmaceutical data sampled from 300 consecutive potential epilepsy-coded cases and 300 randomly chosen cases without epilepsy from 3/7/2012 to 10/7/2013. Two epilepsy specialists independently validated the diagnosis of epilepsy. A multivariable logistic regression model was fitted to identify the optimum coding algorithm for epilepsy and was internally validated. One hundred fifty-eight out of three hundred (52.6%) epilepsy-coded records and 0/300 (0%) nonepilepsy records were confirmed to have epilepsy. The kappa for interrater agreement was 0.89 (95% CI=0.81-0.97). The model utilizing epilepsy (G40), status epilepticus (G41) and ≥1 antiepileptic drug (AED) conferred the highest positive predictive value of 81.4% (95% CI=73.1-87.9) and a specificity of 99.9% (95% CI=99.9-100.0). The area under the receiver operating curve was 0.90 (95% CI=0.88-0.93). When combined with pharmaceutical data, the precision of case identification for epilepsy data linkage design was considerably improved and could provide considerable potential for efficient and reasonably accurate case ascertainment in epidemiological studies. Copyright © 2015 Elsevier Inc. All rights reserved.

A National Study of the Validity and Utility of the Comprehensive Assessment of School Environment (CASE) Survey

ERIC Educational Resources Information Center

McGuffey, Amy R.

2016-01-01

A healthy school climate is necessary for improvement. The purpose of this study was to evaluate the construct validity and usability of the Comprehensive Assessment of School Environment (CASE) as it was purportedly realigned to the three dimensions of the Breaking Ranks Framework developed by the National Association of Secondary School…

A Case Study: Follow-Up Assessment of Facilitated Communication.

ERIC Educational Resources Information Center

Simon, Elliott W.; And Others

1996-01-01

This study of an adolescent with multiple disabilities, including moderate mental retardation, who was reported to engage in validated facilitated communication (FC) found he did not engage in validated FC; performance was equivalent whether food or nonfood reinforcers were used; and the Picture Exchange Communication System was a valid and…

Preliminary Development and Validation of the Mindful Student Questionnaire

ERIC Educational Resources Information Center

Renshaw, Tyler L.

2017-01-01

Research validating mindfulness-based interventions with youths and in schools is growing, yet research validating measures of youths' mindfulness in schools has received far less empirical attention. The present study makes the case for and reports on the preliminary development and validation of a new, 15-item, multidimensional, self-report…

Validation of a Case Definition for Pediatric Brain Injury Using Administrative Data.

PubMed

McChesney-Corbeil, Jane; Barlow, Karen; Quan, Hude; Chen, Guanmin; Wiebe, Samuel; Jette, Nathalie

2017-03-01

Health administrative data are a common population-based data source for traumatic brain injury (TBI) surveillance and research; however, before using these data for surveillance, it is important to develop a validated case definition. The objective of this study was to identify the optimal International Classification of Disease , edition 10 (ICD-10), case definition to ascertain children with TBI in emergency room (ER) or hospital administrative data. We tested multiple case definitions. Children who visited the ER were identified from the Regional Emergency Department Information System at Alberta Children's Hospital. Secondary data were collected for children with trauma, musculoskeletal, or central nervous system complaints who visited the ER between October 5, 2005, and June 6, 2007. TBI status was determined based on chart review. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each case definition. Of 6639 patients, 1343 had a TBI. The best case definition was, "1 hospital or 1 ER encounter coded with an ICD-10 code for TBI in 1 year" (sensitivity 69.8% [95% confidence interval (CI), 67.3-72.2], specificity 96.7% [95% CI, 96.2-97.2], PPV 84.2% [95% CI 82.0-86.3], NPV 92.7% [95% CI, 92.0-93.3]). The nonspecific code S09.9 identified >80% of TBI cases in our study. The optimal ICD-10-based case definition for pediatric TBI in this study is valid and should be considered for future pediatric TBI surveillance studies. However, external validation is recommended before use in other jurisdictions, particularly because it is plausible that a larger proportion of patients in our cohort had milder injuries.

Validity Evidence and Scoring Guidelines for Standardized Patient Encounters and Patient Notes From a Multisite Study of Clinical Performance Examinations in Seven Medical Schools.

PubMed

Park, Yoon Soo; Hyderi, Abbas; Heine, Nancy; May, Win; Nevins, Andrew; Lee, Ming; Bordage, Georges; Yudkowsky, Rachel

2017-11-01

To examine validity evidence of local graduation competency examination scores from seven medical schools using shared cases and to provide rater training protocols and guidelines for scoring patient notes (PNs). Between May and August 2016, clinical cases were developed, shared, and administered across seven medical schools (990 students participated). Raters were calibrated using training protocols, and guidelines were developed collaboratively across sites to standardize scoring. Data included scores from standardized patient encounters for history taking, physical examination, and PNs. Descriptive statistics were used to examine scores from the different assessment components. Generalizability studies (G-studies) using variance components were conducted to estimate reliability for composite scores. Validity evidence was collected for response process (rater perception), internal structure (variance components, reliability), relations to other variables (interassessment correlations), and consequences (composite score). Student performance varied by case and task. In the PNs, justification of differential diagnosis was the most discriminating task. G-studies showed that schools accounted for less than 1% of total variance; however, for the PNs, there were differences in scores for varying cases and tasks across schools, indicating a school effect. Composite score reliability was maximized when the PN was weighted between 30% and 40%. Raters preferred using case-specific scoring guidelines with clear point-scoring systems. This multisite study presents validity evidence for PN scores based on scoring rubric and case-specific scoring guidelines that offer rigor and feedback for learners. Variability in PN scores across participating sites may signal different approaches to teaching clinical reasoning among medical schools.

Development and validation of a melanoma risk score based on pooled data from 16 case-control studies

PubMed Central

Davies, John R; Chang, Yu-mei; Bishop, D Timothy; Armstrong, Bruce K; Bataille, Veronique; Bergman, Wilma; Berwick, Marianne; Bracci, Paige M; Elwood, J Mark; Ernstoff, Marc S; Green, Adele; Gruis, Nelleke A; Holly, Elizabeth A; Ingvar, Christian; Kanetsky, Peter A; Karagas, Margaret R; Lee, Tim K; Le Marchand, Loïc; Mackie, Rona M; Olsson, Håkan; Østerlind, Anne; Rebbeck, Timothy R; Reich, Kristian; Sasieni, Peter; Siskind, Victor; Swerdlow, Anthony J; Titus, Linda; Zens, Michael S; Ziegler, Andreas; Gallagher, Richard P.; Barrett, Jennifer H; Newton-Bishop, Julia

2015-01-01

Background We report the development of a cutaneous melanoma risk algorithm based upon 7 factors; hair colour, skin type, family history, freckling, nevus count, number of large nevi and history of sunburn, intended to form the basis of a self-assessment webtool for the general public. Methods Predicted odds of melanoma were estimated by analysing a pooled dataset from 16 case-control studies using logistic random coefficients models. Risk categories were defined based on the distribution of the predicted odds in the controls from these studies. Imputation was used to estimate missing data in the pooled datasets. The 30th, 60th and 90th centiles were used to distribute individuals into four risk groups for their age, sex and geographic location. Cross-validation was used to test the robustness of the thresholds for each group by leaving out each study one by one. Performance of the model was assessed in an independent UK case-control study dataset. Results Cross-validation confirmed the robustness of the threshold estimates. Cases and controls were well discriminated in the independent dataset (area under the curve 0.75, 95% CI 0.73-0.78). 29% of cases were in the highest risk group compared with 7% of controls, and 43% of controls were in the lowest risk group compared with 13% of cases. Conclusion We have identified a composite score representing an estimate of relative risk and successfully validated this score in an independent dataset. Impact This score may be a useful tool to inform members of the public about their melanoma risk. PMID:25713022

Structured learning for robotic surgery utilizing a proficiency score: a pilot study.

PubMed

Hung, Andrew J; Bottyan, Thomas; Clifford, Thomas G; Serang, Sarfaraz; Nakhoda, Zein K; Shah, Swar H; Yokoi, Hana; Aron, Monish; Gill, Inderbir S

2017-01-01

We evaluated feasibility and benefit of implementing structured learning in a robotics program. Furthermore, we assessed validity of a proficiency assessment tool for stepwise graduation. Teaching cases included robotic radical prostatectomy and partial nephrectomy. Procedure steps were categorized: basic, intermediate, and advanced. An assessment tool ["proficiency score" (PS)] was developed to evaluate ability to safely and autonomously complete a step. Graduation required a passing PS (PS ≥ 3) on three consecutive attempts. PS and validated global evaluative assessment of robotic skills (GEARS) were evaluated for completed steps. Linear regression was utilized to determine postgraduate year/PS relationship (construct validity). Spearman's rank correlation coefficient measured correlation between PS and GEARS evaluations (concurrent validity). Intraclass correlation (ICC) evaluated PS agreement between evaluator classes. Twenty-one robotic trainees participated within the pilot program, completing a median of 14 (2-69) cases each. Twenty-three study evaluators scored 14 (1-60) cases. Over 4 months, 229/294 (78 %) cases were designated "teaching" cases. Residents completed 91 % of possible evaluations; faculty completed 78 %. Verbal and quantitative feedback received by trainees increased significantly (p = 0.002, p < 0.001, respectively). Average PS increased with PGY (post-graduate year) for basic and intermediate steps (regression slopes: 0.402 (p < 0.0001), 0.323 (p < 0.0001), respectively) (construct validation). Overall, PS correlated highly with GEARS (ρ = 0.81, p < 0.0001) (concurrent validity). ICC was 0.77 (95 % CI 0.61-0.88) for resident evaluations. Structured learning can be implemented in an academic robotic program with high levels of trainee and evaluator participation, encouraging both quantitative and verbal feedback. A proficiency assessment tool developed for step-specific proficiency has construct and concurrent validity.

Validation of 2D flood models with insurance claims

NASA Astrophysics Data System (ADS)

Zischg, Andreas Paul; Mosimann, Markus; Bernet, Daniel Benjamin; Röthlisberger, Veronika

2018-02-01

Flood impact modelling requires reliable models for the simulation of flood processes. In recent years, flood inundation models have been remarkably improved and widely used for flood hazard simulation, flood exposure and loss analyses. In this study, we validate a 2D inundation model for the purpose of flood exposure analysis at the river reach scale. We validate the BASEMENT simulation model with insurance claims using conventional validation metrics. The flood model is established on the basis of available topographic data in a high spatial resolution for four test cases. The validation metrics were calculated with two different datasets; a dataset of event documentations reporting flooded areas and a dataset of insurance claims. The model fit relating to insurance claims is in three out of four test cases slightly lower than the model fit computed on the basis of the observed inundation areas. This comparison between two independent validation data sets suggests that validation metrics using insurance claims can be compared to conventional validation data, such as the flooded area. However, a validation on the basis of insurance claims might be more conservative in cases where model errors are more pronounced in areas with a high density of values at risk.

Empirical validation of an agent-based model of wood markets in Switzerland

PubMed Central

Hilty, Lorenz M.; Lemm, Renato; Thees, Oliver

2018-01-01

We present an agent-based model of wood markets and show our efforts to validate this model using empirical data from different sources, including interviews, workshops, experiments, and official statistics. Own surveys closed gaps where data was not available. Our approach to model validation used a variety of techniques, including the replication of historical production amounts, prices, and survey results, as well as a historical case study of a large sawmill entering the market and becoming insolvent only a few years later. Validating the model using this case provided additional insights, showing how the model can be used to simulate scenarios of resource availability and resource allocation. We conclude that the outcome of the rigorous validation qualifies the model to simulate scenarios concerning resource availability and allocation in our study region. PMID:29351300

Towards a full integration of optimization and validation phases: An analytical-quality-by-design approach.

PubMed

Hubert, C; Houari, S; Rozet, E; Lebrun, P; Hubert, Ph

2015-05-22

When using an analytical method, defining an analytical target profile (ATP) focused on quantitative performance represents a key input, and this will drive the method development process. In this context, two case studies were selected in order to demonstrate the potential of a quality-by-design (QbD) strategy when applied to two specific phases of the method lifecycle: the pre-validation study and the validation step. The first case study focused on the improvement of a liquid chromatography (LC) coupled to mass spectrometry (MS) stability-indicating method by the means of the QbD concept. The design of experiments (DoE) conducted during the optimization step (i.e. determination of the qualitative design space (DS)) was performed a posteriori. Additional experiments were performed in order to simultaneously conduct the pre-validation study to assist in defining the DoE to be conducted during the formal validation step. This predicted protocol was compared to the one used during the formal validation. A second case study based on the LC/MS-MS determination of glucosamine and galactosamine in human plasma was considered in order to illustrate an innovative strategy allowing the QbD methodology to be incorporated during the validation phase. An operational space, defined by the qualitative DS, was considered during the validation process rather than a specific set of working conditions as conventionally performed. Results of all the validation parameters conventionally studied were compared to those obtained with this innovative approach for glucosamine and galactosamine. Using this strategy, qualitative and quantitative information were obtained. Consequently, an analyst using this approach would be able to select with great confidence several working conditions within the operational space rather than a given condition for the routine use of the method. This innovative strategy combines both a learning process and a thorough assessment of the risk involved. Copyright © 2015 Elsevier B.V. All rights reserved.

Design and validity of a clinic-based case-control study on the molecular epidemiology of lymphoma

PubMed Central

Cerhan, James R; Fredericksen, Zachary S; Wang, Alice H; Habermann, Thomas M; Kay, Neil E; Macon, William R; Cunningham, Julie M; Shanafelt, Tait D; Ansell, Stephen M; Call, Timothy G; Witzig, Thomas E; Slager, Susan L; Liebow, Mark

2011-01-01

We present the design features and implementation of a clinic-based case-control study on the molecular epidemiology of lymphoma conducted at the Mayo Clinic (Rochester, Minnesota, USA), and then assess the internal and external validity of the study. Cases were newly diagnosed lymphoma patients from Minnesota, Iowa and Wisconsin seen at Mayo and controls were patients from the same region without lymphoma who had a pre-scheduled general medical examination, frequency matched on age, sex and residence. Overall response rates were 67% for cases and 70% for controls; response rates were lower for cases and controls over age 70 years, cases with more aggressive disease, and controls from the local area, although absolute differences were modest. Cases and controls were well-balanced on age, sex, and residence characteristics. Demographic and disease characteristics of NHL cases were similar to population-based cancer registry data. Control distributions were similar to population-based data on lifestyle factors and minor allele frequencies of over 500 SNPs, although smoking rates were slightly lower. Associations with NHL in the Mayo study for smoking, alcohol use, family history of lymphoma, autoimmune disease, asthma, eczema, body mass index, and single nucleotide polymorphisms in TNF (rs1800629), LTA (rs909253), and IL10 (rs1800896) were at a magnitude consistent with estimates from pooled studies in InterLymph, with history of any allergy the only directly discordant result in the Mayo study. These data suggest that this study should have strong internal and external validity. This framework may be useful to others who are designing a similar study. PMID:21686124

Analysis of case-only studies accounting for genotyping error.

PubMed

Cheng, K F

2007-03-01

The case-only design provides one approach to assess possible interactions between genetic and environmental factors. It has been shown that if these factors are conditionally independent, then a case-only analysis is not only valid but also very efficient. However, a drawback of the case-only approach is that its conclusions may be biased by genotyping errors. In this paper, our main aim is to propose a method for analysis of case-only studies when these errors occur. We show that the bias can be adjusted through the use of internal validation data, which are obtained by genotyping some sampled individuals twice. Our analysis is based on a simple and yet highly efficient conditional likelihood approach. Simulation studies considered in this paper confirm that the new method has acceptable performance under genotyping errors.

A STUDY ON A COOPERATIVE RELATIONSHIP TO THE IMPROVEMENT OF THE REGIONAL FIRE FIGHTING VALIDITY -Case Study in Bangkok, Thailand-

NASA Astrophysics Data System (ADS)

Sripramai, Keerati; Oikawa, Yasushi; Watanabe, Hiroshi; Katada, Toshitaka

Generally, in order to improve some regional fire fighting validity, indispensable strategies are not only a reinforcement of the governmental fire fighting ability, but also a strengthening of the cooperative relationship between governmental and non-governmental fire fighting ability. However, for practical purposes, the effective strategy should be different depending on the actual situationin the subject area. So, in this study, we grasp the actual state and background of the problems that need to be solved for the improvement of the regional fire fighting validity in Bangkok as a case study, and examine the appropriate solution focusing on the relationship between official and voluntary fire fighting. Through some practicable activities such as interviews, investigati ons, and making the regional fire fighting validity map, it became clear that the problems of uncooperative relationship and the lack of trust between stakeholders should be solved first and foremost.

The Chinese version of the cognitive, affective, and somatic empathy scale for children: Validation, gender invariance and associated factors.

PubMed

Liu, Jianghong; Qiao, Xin; Dong, Fanghong; Raine, Adrian

2018-01-01

Empathy is hypothesized to have several components, including affective, cognitive, and somatic contributors. The only validated, self-report measure to date that assesses all three forms of empathy is the Cognitive, Affective, and Somatic Empathy Scale (CASES), but no current study has reported the psychometric properties of this scale outside of the initial U.S. sample. This study reports the first psychometric analysis of a non-English translation of the CASES. Confirmatory factor analysis was used to assess the factor structure of CASES as well as its associations with callous-unemotional traits in 860 male and female children (mean age 11.54± .64 years) from the China Jintan Child Cohort Study. Analyses supported a three-factor model of cognitive, affective, and somatic empathy, with satisfactory fit indices consistent with the psychometric properties of the English version of CASES. Construct validity was established by three findings. First, females scored significantly higher in empathy than males. Second, lower scores of empathy were associated with lower IQ. Third, children with lower empathy also showed more callous-unemotional attributes. We established for the first time cross-cultural validity for Cognitive, Affective, and Somatic Empathy Scale (CASES). Our Chinese data supports the use of this new instrument in non-Western samples, and affirms the utility of this instrument for a comprehensive assessment of empathy in children.

Experiences Using Formal Methods for Requirements Modeling

NASA Technical Reports Server (NTRS)

Easterbrook, Steve; Lutz, Robyn; Covington, Rick; Kelly, John; Ampo, Yoko; Hamilton, David

1996-01-01

This paper describes three cases studies in the lightweight application of formal methods to requirements modeling for spacecraft fault protection systems. The case studies differ from previously reported applications of formal methods in that formal methods were applied very early in the requirements engineering process, to validate the evolving requirements. The results were fed back into the projects, to improve the informal specifications. For each case study, we describe what methods were applied, how they were applied, how much effort was involved, and what the findings were. In all three cases, the formal modeling provided a cost effective enhancement of the existing verification and validation processes. We conclude that the benefits gained from early modeling of unstable requirements more than outweigh the effort needed to maintain multiple representations.

Groundwater Model Validation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmed E. Hassan

2006-01-24

Models have an inherent uncertainty. The difficulty in fully characterizing the subsurface environment makes uncertainty an integral component of groundwater flow and transport models, which dictates the need for continuous monitoring and improvement. Building and sustaining confidence in closure decisions and monitoring networks based on models of subsurface conditions require developing confidence in the models through an iterative process. The definition of model validation is postulated as a confidence building and long-term iterative process (Hassan, 2004a). Model validation should be viewed as a process not an end result. Following Hassan (2004b), an approach is proposed for the validation process ofmore » stochastic groundwater models. The approach is briefly summarized herein and detailed analyses of acceptance criteria for stochastic realizations and of using validation data to reduce input parameter uncertainty are presented and applied to two case studies. During the validation process for stochastic models, a question arises as to the sufficiency of the number of acceptable model realizations (in terms of conformity with validation data). Using a hierarchical approach to make this determination is proposed. This approach is based on computing five measures or metrics and following a decision tree to determine if a sufficient number of realizations attain satisfactory scores regarding how they represent the field data used for calibration (old) and used for validation (new). The first two of these measures are applied to hypothetical scenarios using the first case study and assuming field data consistent with the model or significantly different from the model results. In both cases it is shown how the two measures would lead to the appropriate decision about the model performance. Standard statistical tests are used to evaluate these measures with the results indicating they are appropriate measures for evaluating model realizations. The use of validation data to constrain model input parameters is shown for the second case study using a Bayesian approach known as Markov Chain Monte Carlo. The approach shows a great potential to be helpful in the validation process and in incorporating prior knowledge with new field data to derive posterior distributions for both model input and output.« less

CFD Validation Experiment of a Mach 2.5 Axisymmetric Shock-Wave/Boundary-Layer Interaction

NASA Technical Reports Server (NTRS)

Davis, David O.

2015-01-01

Experimental investigations of specific flow phenomena, e.g., Shock Wave Boundary-Layer Interactions (SWBLI), provide great insight to the flow behavior but often lack the necessary details to be useful as CFD validation experiments. Reasons include: 1.Undefined boundary conditions Inconsistent results 2.Undocumented 3D effects (CL only measurements) 3.Lack of uncertainty analysis While there are a number of good subsonic experimental investigations that are sufficiently documented to be considered test cases for CFD and turbulence model validation, the number of supersonic and hypersonic cases is much less. This was highlighted by Settles and Dodsons [1] comprehensive review of available supersonic and hypersonic experimental studies. In all, several hundred studies were considered for their database.Of these, over a hundred were subjected to rigorous acceptance criteria. Based on their criteria, only 19 (12 supersonic, 7 hypersonic) were considered of sufficient quality to be used for validation purposes. Aeschliman and Oberkampf [2] recognized the need to develop a specific methodology for experimental studies intended specifically for validation purposes.

Feasibility study for remote assessment of cognitive function in multiple sclerosis.

PubMed

George, Michaela F; Holingue, Calliope B; Briggs, Farren B S; Shao, Xiaorong; Bellesis, Kalliope H; Whitmer, Rachel A; Schaefer, Catherine; Benedict, Ralph Hb; Barcellos, Lisa F

2016-01-01

Cognitive impairment is common in multiple sclerosis (MS), and affects employment and quality of life. Large studies are needed to identify risk factors for cognitive decline. Currently, a MS-validated remote assessment for cognitive function does not exist. Studies to determine feasibility of large remote cognitive function investigations in MS have not been published. To determine whether MS patients would participate in remote cognitive studies. We utilized the Modified Telephone Interview for Cognitive Status (TICS-M), a previously validated phone assessment for cognitive function in healthy elderly populations to detect mild cognitive impairment. We identified factors that influenced participation rates. We investigated the relationship between MS risk factors and TICS-M score in cases, and score differences between cases and control individuals. The TICS-M was administered to MS cases and controls. Linear and logistic regression models were utilized. 11.5% of eligible study participants did not participate in cognitive testing. MS cases, females and individuals with lower educational status were more likely to refuse (p<0.001). Cases who did complete testing did not differ in terms of perceived cognitive deficit compared to cases that did participate. More severe disease, smoking, and being male were associated with a lower TICS-M score among cases (p<0.001). The TICS-M score was significantly lower in cases compared to controls (p=0.007). Our results demonstrate convincingly that a remotely administered cognitive assessment is quite feasible for conducting large epidemiologic studies in MS, and lay the much needed foundation for future work that will utilize MS-validated cognitive measures.

Feasibility study for remote assessment of cognitive function in multiple sclerosis

PubMed Central

George, Michaela F.; Holingue, Calliope B.; Briggs, Farren B.S.; Shao, Xiaorong; Bellesis, Kalliope H.; Whitmer, Rachel A.; Schaefer, Catherine; Benedict, Ralph HB; Barcellos, Lisa F.

2017-01-01

Background Cognitive impairment is common in multiple sclerosis (MS), and affects employment and quality of life. Large studies are needed to identify risk factors for cognitive decline. Currently, a MS-validated remote assessment for cognitive function does not exist. Studies to determine feasibility of large remote cognitive function investigations in MS have not been published. Objective To determine whether MS patients would participate in remote cognitive studies. We utilized the Modified Telephone Interview for Cognitive Status (TICS-M), a previously validated phone assessment for cognitive function in healthy elderly populations to detect mild cognitive impairment. We identified factors that influenced participation rates. We investigated the relationship between MS risk factors and TICS-M score in cases, and score differences between cases and control individuals. Methods The TICS-M was administered to MS cases and controls. Linear and logistic regression models were utilized. Results 11.5% of eligible study participants did not participate in cognitive testing. MS cases, females and individuals with lower educational status were more likely to refuse (p<0.001). Cases who did complete testing did not differ in terms of perceived cognitive deficit compared to cases that did participate. More severe disease, smoking, and being male were associated with a lower TICS-M score among cases (p<0.001). The TICS-M score was significantly lower in cases compared to controls (p=0.007). Conclusions Our results demonstrate convincingly that a remotely administered cognitive assessment is quite feasible for conducting large epidemiologic studies in MS, and lay the much needed foundation for future work that will utilize MS-validated cognitive measures. PMID:28255581

Measuring stakeholder participation in evaluation: an empirical validation of the Participatory Evaluation Measurement Instrument (PEMI).

PubMed

Daigneault, Pierre-Marc; Jacob, Steve; Tremblay, Joël

2012-08-01

Stakeholder participation is an important trend in the field of program evaluation. Although a few measurement instruments have been proposed, they either have not been empirically validated or do not cover the full content of the concept. This study consists of a first empirical validation of a measurement instrument that fully covers the content of participation, namely the Participatory Evaluation Measurement Instrument (PEMI). It specifically examines (1) the intercoder reliability of scores derived by two research assistants on published evaluation cases; (2) the convergence between the scores of coders and those of key respondents (i.e., authors); and (3) the convergence between the authors' scores on the PEMI and the Evaluation Involvement Scale (EIS). A purposive sample of 40 cases drawn from the evaluation literature was used to assess reliability. One author per case in this sample was then invited to participate in a survey; 25 fully usable questionnaires were received. Stakeholder participation was measured on nominal and ordinal scales. Cohen's κ, the intraclass correlation coefficient, and Spearman's ρ were used to assess reliability and convergence. Reliability results ranged from fair to excellent. Convergence between coders' and authors' scores ranged from poor to good. Scores derived from the PEMI and the EIS were moderately associated. Evidence from this study is strong in the case of intercoder reliability and ranges from weak to strong in the case of convergent validation. Globally, this suggests that the PEMI can produce scores that are both reliable and valid.

Simulation model calibration and validation : phase II : development of implementation handbook and short course.

DOT National Transportation Integrated Search

2006-01-01

A previous study developed a procedure for microscopic simulation model calibration and validation and evaluated the procedure via two relatively simple case studies using three microscopic simulation models. Results showed that default parameters we...

Repetitive deliberate fires: Development and validation of a methodology to detect series.

PubMed

Bruenisholz, Eva; Delémont, Olivier; Ribaux, Olivier; Wilson-Wilde, Linzi

2017-08-01

The detection of repetitive deliberate fire events is challenging and still often ineffective due to a case-by-case approach. A previous study provided a critical review of the situation and analysis of the main challenges. This study suggested that the intelligence process, integrating forensic data, could be a valid framework to provide a follow-up and systematic analysis provided it is adapted to the specificities of repetitive deliberate fires. In this current manuscript, a specific methodology to detect deliberate fires series, i.e. set by the same perpetrators, is presented and validated. It is based on case profiles relying on specific elements previously identified. The method was validated using a dataset of approximately 8000 deliberate fire events collected over 12 years in a Swiss state. Twenty possible series were detected, including 6 of 9 known series. These results are very promising and lead the way to a systematic implementation of this methodology in an intelligence framework, whilst demonstrating the need and benefit of increasing the collection of forensic specific information to strengthen the value of links between cases. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Validation of the GreenLight™ Simulator and development of a training curriculum for photoselective vaporisation of the prostate.

PubMed

Aydin, Abdullatif; Muir, Gordon H; Graziano, Manuela E; Khan, Muhammad Shamim; Dasgupta, Prokar; Ahmed, Kamran

2015-06-01

To assess face, content and construct validity, and feasibility and acceptability of the GreenLight™ Simulator as a training tool for photoselective vaporisation of the prostate (PVP), and to establish learning curves and develop an evidence-based training curriculum. This prospective, observational and comparative study, recruited novice (25 participants), intermediate (14) and expert-level urologists (seven) from the UK and Europe at the 28th European Association of Urological Surgeons Annual Meeting 2013. A group of novices (12 participants) performed 10 sessions of subtask training modules followed by a long operative case, whereas a second group (13) performed five sessions of a given case module. Intermediate and expert groups performed all training modules once, followed by one operative case. The outcome measures for learning curves and construct validity were time to task, coagulation time, vaporisation time, average sweep speed, average laser distance, blood loss, operative errors, and instrument cost. Face and content validity, feasibility and acceptability were addressed through a quantitative survey. Construct validity was demonstrated in two of five training modules (P = 0.038; P = 0.018) and in a considerable number of case metrics (P = 0.034). Learning curves were seen in all five training modules (P < 0.001) and significant reduction in case operative time (P < 0.001) and error (P = 0.017) were seen. An evidence-based training curriculum, to help trainees acquire transferable skills, was produced using the results. This study has shown the GreenLight Simulator to be a valid and useful training tool for PVP. It is hoped that by using the training curriculum for the GreenLight Simulator, novice trainees can acquire skills and knowledge to a predetermined level of proficiency. © 2014 The Authors. BJU International © 2014 BJU International.

Quantifying the foodscape: A systematic review and meta-analysis of the validity of commercially available business data.

PubMed

Lebel, Alexandre; Daepp, Madeleine I G; Block, Jason P; Walker, Renée; Lalonde, Benoît; Kestens, Yan; Subramanian, S V

2017-01-01

This paper reviews studies of the validity of commercially available business (CAB) data on food establishments ("the foodscape"), offering a meta-analysis of characteristics associated with CAB quality and a case study evaluating the performance of commonly-used validity indicators describing the foodscape. Existing validation studies report a broad range in CAB data quality, although most studies conclude that CAB quality is "moderate" to "substantial". We conclude that current studies may underestimate the quality of CAB data. We recommend that future validation studies use density-adjusted and exposure measures to offer a more meaningful characterization of the relationship of data error with spatial exposure.

Quantifying the foodscape: A systematic review and meta-analysis of the validity of commercially available business data

PubMed Central

Lebel, Alexandre; Daepp, Madeleine I. G.; Block, Jason P.; Walker, Renée; Lalonde, Benoît; Kestens, Yan; Subramanian, S. V.

2017-01-01

This paper reviews studies of the validity of commercially available business (CAB) data on food establishments (“the foodscape”), offering a meta-analysis of characteristics associated with CAB quality and a case study evaluating the performance of commonly-used validity indicators describing the foodscape. Existing validation studies report a broad range in CAB data quality, although most studies conclude that CAB quality is “moderate” to “substantial”. We conclude that current studies may underestimate the quality of CAB data. We recommend that future validation studies use density-adjusted and exposure measures to offer a more meaningful characterization of the relationship of data error with spatial exposure. PMID:28358819

Predictive value of autoantibody testing for validating self-reported diagnoses of rheumatoid arthritis in the Women's Health Initiative.

PubMed

Walitt, Brian; Mackey, Rachel; Kuller, Lewis; Deane, Kevin D; Robinson, William; Holers, V Michael; Chang, Yue-Fang; Moreland, Larry

2013-05-01

Rheumatoid arthritis (RA) research using large databases is limited by insufficient case validity. Of 161,808 postmenopausal women in the Women's Health Initiative, 15,691 (10.2%) reported having RA, far higher than the expected 1% population prevalence. Since chart review for confirmation of an RA diagnosis is impractical in large cohort studies, the current study (2009-2011) tested the ability of baseline serum measurements of rheumatoid factor and anti-cyclic citrullinated peptide antibodies, second-generation assay (anti-CCP2), to identify physician-validated RA among the chart-review study participants with self-reported RA (n = 286). Anti-CCP2 positivity had the highest positive predictive value (PPV) (80.0%), and rheumatoid factor positivity the lowest (44.6%). Together, use of disease-modifying antirheumatic drugs and anti-CCP2 positivity increased PPV to 100% but excluded all seronegative cases (approximately 15% of all RA cases). Case definitions inclusive of seronegative cases had PPVs between 59.6% and 63.6%. False-negative results were minimized in these test definitions, as evidenced by negative predictive values of approximately 90%. Serological measurements, particularly measurement of anti-CCP2, improved the test characteristics of RA case definitions in the Women's Health Initiative.

Validity of a PCR assay in CSF for the diagnosis of neurocysticercosis.

PubMed

Carpio, Arturo; Campoverde, Alfredo; Romo, Matthew L; García, Lorena; Piedra, Luis M; Pacurucu, Mónica; López, Nelson; Aguilar, Jenner; López, Sebastian; Vintimilla, Luis C; Toral, Ana M; Peña-Tapia, Pablo

2017-03-01

To prospectively evaluate the validity of a PCR assay in CSF for the diagnosis of neurocysticercosis (NC). We conducted a multicenter, prospective case-control study, recruiting participants from 5 hospitals in Cuenca, Ecuador, from January 2015 to February 2016. Cases fulfilled validated diagnostic criteria for NC. For each case, a neurosurgical patient who did not fulfill the diagnostic criteria for NC was selected as a control. CT and MRI, as well as a CSF sample, were collected from both cases and controls. The diagnostic criteria to identify cases were used as a reference standard. Overall, 36 case and 36 control participants were enrolled. PCR had a sensitivity of 72.2% (95% confidence interval [CI] 54.8%-85.8%) and a specificity of 100.0% (95% CI 90.3%-100.0%). For parenchymal NC, PCR had a sensitivity of 42.9% (95% CI 17.7%-71.1%), and for extraparenchymal NC, PCR had a sensitivity of 90.9% (95% CI 70.8%-98.9%). This study demonstrated the usefulness of this PCR assay in CSF for the diagnosis of NC. PCR may be particularly helpful for diagnosing extraparenchymal NC when neuroimaging techniques have failed. This study provides Class III evidence that CSF PCR can accurately identify patients with extraparenchymal NC.

Validation of a computer case definition for sudden cardiac death in opioid users.

PubMed

Kawai, Vivian K; Murray, Katherine T; Stein, C Michael; Cooper, William O; Graham, David J; Hall, Kathi; Ray, Wayne A

2012-08-31

To facilitate the use of automated databases for studies of sudden cardiac death, we previously developed a computerized case definition that had a positive predictive value between 86% and 88%. However, the definition has not been specifically validated for prescription opioid users, for whom out-of-hospital overdose deaths may be difficult to distinguish from sudden cardiac death. We assembled a cohort of persons 30-74 years of age prescribed propoxyphene or hydrocodone who had no life-threatening non-cardiovascular illness, diagnosed drug abuse, residence in a nursing home in the past year, or hospital stay within the past 30 days. Medical records were sought for a sample of 140 cohort deaths within 30 days of a prescription fill meeting the computer case definition. Of the 140 sampled deaths, 81 were adjudicated; 73 (90%) were sudden cardiac deaths. Two deaths had possible opioid overdose; after removing these two the positive predictive value was 88%. These findings are consistent with our previous validation studies and suggest the computer case definition of sudden cardiac death is a useful tool for pharmacoepidemiologic studies of opioid analgesics.

Analysis of 2000 cases treated with gamma knife surgery: validating eligibility criteria for a prospective multi-institutional study of stereotactic radiosurgery alone for treatment of patients with 1-10 brain metastases (JLGK0901) in Japan

PubMed Central

Higuchi, Yoshinori; Nagano, Osamu; Sato, Yasunori; Yamamoto, Masaaki; Ono, Junichi; Saeki, Naokatsu; Miyakawa, Akifumi; Hirai, Tatsuo

2012-01-01

Objective The Japan Leksell Gamma Knife (JLGK) Society has conducted a prospective multi-institute study (JLGK0901, UNIN000001812) for selected patients in order to prove the effectiveness of stereotactic radiosurgery (SRS) alone using the gamma knife (GK) for 1-10 brain lesions. Herein, we verify the validity of 5 major patient selection criteria for the JLGK0901 trial. Materials and Methods Between 1998 and 2010, 2246 consecutive cases with 10352 brain metastases treated with GK were analyzed to determine the validity of the following 5 major JLGK0901 criteria; 1) 1-10 brain lesions, 2) less than 10 cm3 volume of the largest tumor, 3) no more than 15 cm3 total tumor volume, 4) no cerebrospinal fluid (CSF) dissemination, 5) Karnofsky performance status (KPS) score ≥70. Results For cases with >10 brain metastases, salvage treatments for new lesions were needed more frequently. The tumor control rate for lesions larger than 10 cm3 was significantly lower than that of tumors <10 cm3. Overall, neurological and qualitative survivals (OS, NS, QS) of cases with >15 cm3 total tumor volume or positive magnetic resonance imaging findings of CSF were significantly poorer. Outcomes in cases with KPS <70 were significantly poorer in terms of OS. Conclusion Our retrospective results of 2246 GK-treated cases verified the validity of the 5 major JLGK0901 criteria. The inclusion criteria for the JLGK0901 study are appearently good indications for SRS. PMID:29296339

MicroRNA expression in benign breast tissue and risk of subsequent invasive breast cancer.

PubMed

Rohan, Thomas; Ye, Kenny; Wang, Yihong; Glass, Andrew G; Ginsberg, Mindy; Loudig, Olivier

2018-01-01

MicroRNAs are endogenous, small non-coding RNAs that control gene expression by directing their target mRNAs for degradation and/or posttranscriptional repression. Abnormal expression of microRNAs is thought to contribute to the development and progression of cancer. A history of benign breast disease (BBD) is associated with increased risk of subsequent breast cancer. However, no large-scale study has examined the association between microRNA expression in BBD tissue and risk of subsequent invasive breast cancer (IBC). We conducted discovery and validation case-control studies nested in a cohort of 15,395 women diagnosed with BBD in a large health plan between 1971 and 2006 and followed to mid-2015. Cases were women with BBD who developed subsequent IBC; controls were matched 1:1 to cases on age, age at diagnosis of BBD, and duration of plan membership. The discovery stage (316 case-control pairs) entailed use of the Illumina MicroRNA Expression Profiling Assay (in duplicate) to identify breast cancer-associated microRNAs. MicroRNAs identified at this stage were ranked by the strength of the correlation between Illumina array and quantitative PCR results for 15 case-control pairs. The top ranked 14 microRNAs entered the validation stage (165 case-control pairs) which was conducted using quantitative PCR (in triplicate). In both stages, linear regression was used to evaluate the association between the mean expression level of each microRNA (response variable) and case-control status (independent variable); paired t-tests were also used in the validation stage. None of the 14 validation stage microRNAs was associated with breast cancer risk. The results of this study suggest that microRNA expression in benign breast tissue does not influence the risk of subsequent IBC.

MicroRNA expression in benign breast tissue and risk of subsequent invasive breast cancer

PubMed Central

Ye, Kenny; Wang, Yihong; Ginsberg, Mindy; Loudig, Olivier

2018-01-01

MicroRNAs are endogenous, small non-coding RNAs that control gene expression by directing their target mRNAs for degradation and/or posttranscriptional repression. Abnormal expression of microRNAs is thought to contribute to the development and progression of cancer. A history of benign breast disease (BBD) is associated with increased risk of subsequent breast cancer. However, no large-scale study has examined the association between microRNA expression in BBD tissue and risk of subsequent invasive breast cancer (IBC). We conducted discovery and validation case-control studies nested in a cohort of 15,395 women diagnosed with BBD in a large health plan between 1971 and 2006 and followed to mid-2015. Cases were women with BBD who developed subsequent IBC; controls were matched 1:1 to cases on age, age at diagnosis of BBD, and duration of plan membership. The discovery stage (316 case-control pairs) entailed use of the Illumina MicroRNA Expression Profiling Assay (in duplicate) to identify breast cancer-associated microRNAs. MicroRNAs identified at this stage were ranked by the strength of the correlation between Illumina array and quantitative PCR results for 15 case-control pairs. The top ranked 14 microRNAs entered the validation stage (165 case-control pairs) which was conducted using quantitative PCR (in triplicate). In both stages, linear regression was used to evaluate the association between the mean expression level of each microRNA (response variable) and case-control status (independent variable); paired t-tests were also used in the validation stage. None of the 14 validation stage microRNAs was associated with breast cancer risk. The results of this study suggest that microRNA expression in benign breast tissue does not influence the risk of subsequent IBC. PMID:29432432

The validation index: a new metric for validation of segmentation algorithms using two or more expert outlines with application to radiotherapy planning.

PubMed

Juneja, Prabhjot; Evans, Philp M; Harris, Emma J

2013-08-01

Validation is required to ensure automated segmentation algorithms are suitable for radiotherapy target definition. In the absence of true segmentation, algorithmic segmentation is validated against expert outlining of the region of interest. Multiple experts are used to overcome inter-expert variability. Several approaches have been studied in the literature, but the most appropriate approach to combine the information from multiple expert outlines, to give a single metric for validation, is unclear. None consider a metric that can be tailored to case-specific requirements in radiotherapy planning. Validation index (VI), a new validation metric which uses experts' level of agreement was developed. A control parameter was introduced for the validation of segmentations required for different radiotherapy scenarios: for targets close to organs-at-risk and for difficult to discern targets, where large variation between experts is expected. VI was evaluated using two simulated idealized cases and data from two clinical studies. VI was compared with the commonly used Dice similarity coefficient (DSCpair - wise) and found to be more sensitive than the DSCpair - wise to the changes in agreement between experts. VI was shown to be adaptable to specific radiotherapy planning scenarios.

Experiences Using Lightweight Formal Methods for Requirements Modeling

NASA Technical Reports Server (NTRS)

Easterbrook, Steve; Lutz, Robyn; Covington, Rick; Kelly, John; Ampo, Yoko; Hamilton, David

1997-01-01

This paper describes three case studies in the lightweight application of formal methods to requirements modeling for spacecraft fault protection systems. The case studies differ from previously reported applications of formal methods in that formal methods were applied very early in the requirements engineering process, to validate the evolving requirements. The results were fed back into the projects, to improve the informal specifications. For each case study, we describe what methods were applied, how they were applied, how much effort was involved, and what the findings were. In all three cases, formal methods enhanced the existing verification and validation processes, by testing key properties of the evolving requirements, and helping to identify weaknesses. We conclude that the benefits gained from early modeling of unstable requirements more than outweigh the effort needed to maintain multiple representations.

A Framework for Mixing Methods in Quantitative Measurement Development, Validation, and Revision: A Case Study

ERIC Educational Resources Information Center

Luyt, Russell

2012-01-01

A framework for quantitative measurement development, validation, and revision that incorporates both qualitative and quantitative methods is introduced. It extends and adapts Adcock and Collier's work, and thus, facilitates understanding of quantitative measurement development, validation, and revision as an integrated and cyclical set of…

Code-based Diagnostic Algorithms for Idiopathic Pulmonary Fibrosis. Case Validation and Improvement.

PubMed

Ley, Brett; Urbania, Thomas; Husson, Gail; Vittinghoff, Eric; Brush, David R; Eisner, Mark D; Iribarren, Carlos; Collard, Harold R

2017-06-01

Population-based studies of idiopathic pulmonary fibrosis (IPF) in the United States have been limited by reliance on diagnostic code-based algorithms that lack clinical validation. To validate a well-accepted International Classification of Diseases, Ninth Revision, code-based algorithm for IPF using patient-level information and to develop a modified algorithm for IPF with enhanced predictive value. The traditional IPF algorithm was used to identify potential cases of IPF in the Kaiser Permanente Northern California adult population from 2000 to 2014. Incidence and prevalence were determined overall and by age, sex, and race/ethnicity. A validation subset of cases (n = 150) underwent expert medical record and chest computed tomography review. A modified IPF algorithm was then derived and validated to optimize positive predictive value. From 2000 to 2014, the traditional IPF algorithm identified 2,608 cases among 5,389,627 at-risk adults in the Kaiser Permanente Northern California population. Annual incidence was 6.8/100,000 person-years (95% confidence interval [CI], 6.1-7.7) and was higher in patients with older age, male sex, and white race. The positive predictive value of the IPF algorithm was only 42.2% (95% CI, 30.6 to 54.6%); sensitivity was 55.6% (95% CI, 21.2 to 86.3%). The corrected incidence was estimated at 5.6/100,000 person-years (95% CI, 2.6-10.3). A modified IPF algorithm had improved positive predictive value but reduced sensitivity compared with the traditional algorithm. A well-accepted International Classification of Diseases, Ninth Revision, code-based IPF algorithm performs poorly, falsely classifying many non-IPF cases as IPF and missing a substantial proportion of IPF cases. A modification of the IPF algorithm may be useful for future population-based studies of IPF.

The Chinese version of the Child and Adolescent Scale of Environment (CASE-C): validity and reliability for children with disabilities in Taiwan.

PubMed

Kang, Lin-Ju; Yen, Chia-Feng; Bedell, Gary; Simeonsson, Rune J; Liou, Tsan-Hon; Chi, Wen-Chou; Liu, Shu-Wen; Liao, Hua-Fang; Hwang, Ai-Wen

2015-03-01

Measurement of children's participation and environmental factors is a key component of the assessment in the new Disability Evaluation System (DES) in Taiwan. The Child and Adolescent Scale of Environment (CASE) was translated into Traditional Chinese (CASE-C) and used for assessing environmental factors affecting the participation of children and youth with disabilities in the DES. The aim of this study was to validate the CASE-C. Participants were 614 children and youth aged 6.0-17.9 years with disabilities, with the largest condition group comprised of children with intellectual disability (61%). Internal structure, internal consistency, test-retest reliability, convergent validity, and discriminant (known group) validity were examined using exploratory factor analyses, Cronbach's α coefficient, intra-class correlation coefficients (ICC), correlation analyses, and univariate ANOVAs. A three-factor structure (Family/Community Resources, Assistance/Attitude Supports, and Physical Design Access) of the CASE-C was produced with 38% variance explained. The CASE-C had adequate internal consistency (Cronbach's α=.74-.86) and test-retest reliability (ICCs=.73-.90). Children and youth with disabilities who had higher levels of severity of impairment encountered more environmental barriers and those experiencing more environmental problems also had greater restrictions in participation. The CASE-C scores were found to distinguish children on the basis of disability condition and impairment severity, but not on the basis of age or sex. The CASE-C is valid for assessing environmental problems experienced by children and youth with disabilities in Taiwan. Copyright © 2014 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lundstrom, Blake; Chakraborty, Sudipta; Lauss, Georg

This paper presents a concise description of state-of-the-art real-time simulation-based testing methods and demonstrates how they can be used independently and/or in combination as an integrated development and validation approach for smart grid DERs and systems. A three-part case study demonstrating the application of this integrated approach at the different stages of development and validation of a system-integrated smart photovoltaic (PV) inverter is also presented. Laboratory testing results and perspectives from two international research laboratories are included in the case study.

Combining Advanced Turbulent Mixing and Combustion Models with Advanced Multi-Phase CFD Code to Simulate Detonation and Post-Detonation Bio-Agent Mixing and Destruction

DTIC Science & Technology

2017-10-01

perturbations in the energetic material to study their effects on the blast wave formation. The last case also makes use of the same PBX, however, the...configuration, Case A: Spore cloud located on the top of the charge at an angle 45 degree, Case B: Spore cloud located at an angle 45 degree from the charge...theoretical validation. The first is the Sedov case where the pressure decay and blast wave front are validated based on analytical solutions. In this test

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rearden, Bradley T; Marshall, William BJ J

In the course of criticality code validation, outlier cases are frequently encountered. Historically, the causes of these unexpected results could be diagnosed only through comparison with other similar cases or through the known presence of a unique component of the critical experiment. The sensitivity and uncertainty (S/U) analysis tools available in the SCALE 6.1 code system provide a much broader range of options to examine underlying causes of outlier cases. This paper presents some case studies performed as a part of the recent validation of the KENO codes in SCALE 6.1 using S/U tools to examine potential causes of biases.

Complexity, Representation and Practice: Case Study as Method and Methodology

ERIC Educational Resources Information Center

Miles, Rebecca

2015-01-01

While case study is considered a common approach to examining specific and particular examples in research disciplines such as law, medicine and psychology, in the social sciences case study is often treated as a lesser, flawed or undemanding methodology which is less valid, reliable or theoretically rigorous than other methodologies. Building on…

Face and construct validation of a next generation virtual reality (Gen2-VR) surgical simulator.

PubMed

Sankaranarayanan, Ganesh; Li, Baichun; Manser, Kelly; Jones, Stephanie B; Jones, Daniel B; Schwaitzberg, Steven; Cao, Caroline G L; De, Suvranu

2016-03-01

Surgical performance is affected by distractors and interruptions to surgical workflow that exist in the operating room. However, traditional surgical simulators are used to train surgeons in a skills laboratory that does not recreate these conditions. To overcome this limitation, we have developed a novel, immersive virtual reality (Gen2-VR) system to train surgeons in these environments. This study was to establish face and construct validity of our system. The study was a within-subjects design, with subjects repeating a virtual peg transfer task under three different conditions: Case I: traditional VR; Case II: Gen2-VR with no distractions and Case III: Gen2-VR with distractions and interruptions. In Case III, to simulate the effects of distractions and interruptions, music was played intermittently, the camera lens was fogged for 10 s and tools malfunctioned for 15 s at random points in time during the simulation. At the completion of the study subjects filled in a 5-point Likert scale feedback questionnaire. A total of sixteen subjects participated in this study. Friedman test showed significant difference in scores between the three conditions (p < 0.0001). Post hoc analysis using Wilcoxon signed-rank tests with Bonferroni correction further showed that all the three conditions were significantly different from each other (Case I, Case II, p < 0.0001), (Case I, Case III, p < 0.0001) and (Case II, Case III, p = 0.009). Subjects rated that fog (mean 4.18) and tool malfunction (median 4.56) significantly hindered their performance. The results showed that Gen2-VR simulator has both face and construct validity and that it can accurately and realistically present distractions and interruptions in a simulated OR, in spite of limitations of the current HMD hardware technology.

Face and Construct Validation of a Next Generation Virtual Reality (Gen2-VR©) Surgical Simulator

PubMed Central

Sankaranarayanan, Ganesh; Li, Baichun; Manser, Kelly; Jones, Stephanie B.; Jones, Daniel B.; Schwaitzberg, Steven; Cao, Caroline G. L.; De, Suvranu

2015-01-01

Introduction Surgical performance is affected by distractors and interruptions to surgical workflow that exist in the operating room. However, traditional surgical simulators are used to train surgeons in a skills lab that does not recreate these conditions. To overcome this limitation, we have developed a novel, immersive virtual reality (Gen2-VR©) system to train surgeons in these environments. This study was to establish face and construct validity of our system. Methods and Procedures The study was a within-subjects design, with subjects repeating a virtual peg transfer task under three different conditions: CASE I: traditional VR; CASE II: Gen2-VR© with no distractions and CASE III: Gen2-VR© with distractions and interruptions.. In Case III, to simulate the effects of distractions and interruptions, music was played intermittently, the camera lens was fogged for 10 seconds and tools malfunctioned for 15 seconds at random points in time during the simulation. At the completion of the study subjects filled in a 5-point Likert scale feedback questionnaire. A total of sixteen subjects participated in this study. Results Friedman test showed significant difference in scores between the three conditions (p < 0.0001). Post hoc analysis using Wilcoxon Signed Rank tests with Bonferroni correction further showed that all the three conditions were significantly different from each other (Case I, Case II, p < 0.001), (Case I, Case III, p < 0.001) and (Case II, Case III, p = 0.009). Subjects rated that fog (mean= 4.18) and tool malfunction (median = 4.56) significantly hindered their performance. Conclusion The results showed that Gen2-VR© simulator has both face and construct validity and it can accurately and realistically present distractions and interruptions in a simulated OR, in spite of limitations of the current HMD hardware technology. PMID:26092010

Validation of the trait anxiety scale for state-trait anxiety inventory in suicide victims and living controls of Chinese rural youths.

PubMed

Zhang, Jie; Gao, Qi

2012-01-01

This study evaluated the validation of STAI Trait-Anxiety Scale in suicide cases and community living controls in rural China. The participants were 392 suicides and 416 controls. Cronbach's Alpha was computed to evaluate the internal consistency. The Spearman Correlation Coefficient between Trait-Anxiety Scale and other instrument was calculated to evaluate the external validity, and the Exploratory Factor Analysis was used to evaluate the construct validity. The results showed the Cronbach's Alpha was .891 and .787 respectively in case and control groups. Most of the correlations between instruments were significant. We found 2 factors in cases and 3 factors in controls. We could cautiously infer that the Trait Anxiety Scale was an adequate tool to measure trait anxiety through proxy data in suicide victims and living controls in rural China.

The Clinical Interview Schedule-Revised (CIS-R)-Malay Version, Clinical Validation.

PubMed

Subramaniam, Kavitha; Krishnaswamy, Saroja; Jemain, Abdul Aziz; Hamid, Abdul; Patel, Vikram

2006-01-01

Use of instruments or questionnaires in different cultural settings without proper validation can result in inaccurate results. Issues like reliability, validity, feasibility and acceptability should be considered in the use of an instrument. The study aims to determine the usefulness of the CIS-R Malay version in detecting common mental health problems specifically to establish the validity. The CIS-R instrument (PROQSY* format) was translated through the back translation process into Malay. Inter rater reliability was established for raters who were medical students. Cases and controls for the study were psychiatric in patients, out patient and relatives or friends accompanying the patients to the clinic or visiting the inpatients. The Malay version of CIS-R was administered to all cases and controls. All cases and controls involved in the study were rated by psychiatrists for psychiatric morbidity using the SCID as a guideline. Specificity and sensitivity of the CIS-R to the assessment by the psychiatrist were determined. The Malay version of CIS-R showed 100% sensitivity and 96.15% specificity at a cut off score of 9. The CIS-R can be a useful instrument for clinical and research use in the Malaysian population for diagnosing common mental disorders like depression and anxiety.

A scoring system for ascertainment of incident stroke; the Risk Index Score (RISc).

PubMed

Kass-Hout, T A; Moyé, L A; Smith, M A; Morgenstern, L B

2006-01-01

The main objective of this study was to develop and validate a computer-based statistical algorithm that could be translated into a simple scoring system in order to ascertain incident stroke cases using hospital admission medical records data. The Risk Index Score (RISc) algorithm was developed using data collected prospectively by the Brain Attack Surveillance in Corpus Christi (BASIC) project, 2000. The validity of RISc was evaluated by estimating the concordance of scoring system stroke ascertainment to stroke ascertainment by physician and/or abstractor review of hospital admission records. RISc was developed on 1718 randomly selected patients (training set) and then statistically validated on an independent sample of 858 patients (validation set). A multivariable logistic model was used to develop RISc and subsequently evaluated by goodness-of-fit and receiver operating characteristic (ROC) analyses. The higher the value of RISc, the higher the patient's risk of potential stroke. The study showed RISc was well calibrated and discriminated those who had potential stroke from those that did not on initial screening. In this study we developed and validated a rapid, easy, efficient, and accurate method to ascertain incident stroke cases from routine hospital admission records for epidemiologic investigations. Validation of this scoring system was achieved statistically; however, clinical validation in a community hospital setting is warranted.

Exploring a Framework for Consequential Validity for Performance-Based Assessments

ERIC Educational Resources Information Center

Kim, Su Jung

2017-01-01

This study explores a new comprehensive framework for understanding elements of validity, specifically for performance assessments that are administered within specific and dynamic contexts. The adoption of edTPA is a good empirical case for examining the concept of consequential validity because this assessment has been implemented at the state…

eLearning to facilitate the education and implementation of the Chelsea Critical Care Physical Assessment: a novel measure of function in critical illness

PubMed Central

Corner, Evelyn J; Handy, Jonathan M; Brett, Stephen J

2016-01-01

Objective To evaluate the efficacy of eLearning in the widespread standardised teaching, distribution and implementation of the Chelsea Critical Care Physical Assessment (CPAx) tool—a validated tool to assess physical function in critically ill patients. Design Prospective educational study. An eLearning module was developed through a conceptual framework, using the four-stage technique for skills teaching to teach clinicians how to use the CPAx. Example and test video case studies of CPAx assessments were embedded within the module. The CPAx scores for the test case studies and demographic data were recorded in a secure area of the website. Data were analysed for inter-rater reliability using intraclass correlation coefficients (ICCs) to see if an eLearning educational package facilitated consistent use of the tool. A utility and content validity questionnaire was distributed after 1 year to eLearning module registrants (n=971). This was to evaluate uptake of the CPAx in clinical practice and content validity of the CPAx from the perspective of clinical users. Setting The module was distributed for use via professional forums (n=2) and direct contacts (n=95). Participants Critical care clinicians. Primary outcome measure ICC of the test case studies. Results Between July and October 2014, 421 candidates from 15 countries registered for the eLearning module. The ICC for case one was 0.996 (95% CI 0.990 to 0.999; n=207). The ICC for case two was 0.988 (0.996 to 1.000; n=184). The CPAx has a strong total scale content validity index (s-CVI) of 0.94 and is well used. Conclusions eLearning is a useful and reliable way of teaching psychomotor skills, such as the CPAx. The CPAx is a well-used measure with high content validity rated by clinicians. PMID:27067895

eLearning to facilitate the education and implementation of the Chelsea Critical Care Physical Assessment: a novel measure of function in critical illness.

PubMed

Corner, Evelyn J; Handy, Jonathan M; Brett, Stephen J

2016-04-11

To evaluate the efficacy of eLearning in the widespread standardised teaching, distribution and implementation of the Chelsea Critical Care Physical Assessment (CPAx) tool-a validated tool to assess physical function in critically ill patients. Prospective educational study. An eLearning module was developed through a conceptual framework, using the four-stage technique for skills teaching to teach clinicians how to use the CPAx. Example and test video case studies of CPAx assessments were embedded within the module. The CPAx scores for the test case studies and demographic data were recorded in a secure area of the website. Data were analysed for inter-rater reliability using intraclass correlation coefficients (ICCs) to see if an eLearning educational package facilitated consistent use of the tool. A utility and content validity questionnaire was distributed after 1 year to eLearning module registrants (n=971). This was to evaluate uptake of the CPAx in clinical practice and content validity of the CPAx from the perspective of clinical users. The module was distributed for use via professional forums (n=2) and direct contacts (n=95). Critical care clinicians. ICC of the test case studies. Between July and October 2014, 421 candidates from 15 countries registered for the eLearning module. The ICC for case one was 0.996 (95% CI 0.990 to 0.999; n=207). The ICC for case two was 0.988 (0.996 to 1.000; n=184). The CPAx has a strong total scale content validity index (s-CVI) of 0.94 and is well used. eLearning is a useful and reliable way of teaching psychomotor skills, such as the CPAx. The CPAx is a well-used measure with high content validity rated by clinicians. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Agent-Based vs. Equation-based Epidemiological Models:A Model Selection Case Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sukumar, Sreenivas R; Nutaro, James J

This paper is motivated by the need to design model validation strategies for epidemiological disease-spread models. We consider both agent-based and equation-based models of pandemic disease spread and study the nuances and complexities one has to consider from the perspective of model validation. For this purpose, we instantiate an equation based model and an agent based model of the 1918 Spanish flu and we leverage data published in the literature for our case- study. We present our observations from the perspective of each implementation and discuss the application of model-selection criteria to compare the risk in choosing one modeling paradigmmore » to another. We conclude with a discussion of our experience and document future ideas for a model validation framework.« less

[Influence of trigeminal nerve lesion on facial growth: study of two cases of Goldenhar syndrome].

PubMed

Darris, Pierre; Treil, Jacques; Marchal-Sixou, Christine; Baron, Pascal

2015-06-01

This cases report confirms the hypothesis that embryonic and maxillofacial growth are influenced by the peripheral nervous system, including the trigeminal nerve (V). So, it's interesting to use the stigma of the trigeminal nerve as landmarks to analyze the maxillofacial volume and understand its growth. The aim of this study is to evaluate the validity of the three-dimensional cephalometric analysis of Treil based on trigeminal landmarks. The first case is a caucasian female child with Goldenhar syndrome. The second case is a caucasian male adult affected by the same syndrome. In both cases, brain MRI showed an unilateral trigeminal nerve lesion, ipsilateral to the facial dysmorphia. The results of this radiological study tend to prove the primary role of the trigeminal nerve in craniofacial growth. These cases demonstrate the validity of the theory of Moss. They are one of anatomo-functional justifications of the three-dimensional cephalometric biometry of Treil based on trigeminal nerve landmarks. © EDP Sciences, SFODF, 2015.

Numerical Analysis Study of Sarawak Barrage River Bed Erosion and Scouring by Using Smooth Particle Hydrodynamic (SPH)

NASA Astrophysics Data System (ADS)

Zainol, M. R. R. M. A.; Kamaruddin, M. A.; Zawawi, M. H.; Wahab, K. A.

2017-11-01

Smooth Particle Hydrodynamic is the three-dimensional (3D) model. In this research work, three cases and one validation have been simulate using DualSPHysics. Study area of this research work was at Sarawak Barrage. The cases have different water level at the downstream. This study actually to simulate riverbed erosion and scouring properties by using multi-phases cases which use sand as sediment and water. The velocity and the scouring profile have been recorded as the result and shown in the result chapter. The result of the validation is acceptable where the scouring profile and the velocity were slightly different between laboratory experiment and simulation. Hence, it can be concluded that the simulation by using SPH can be used as the alternative to simulate the real cases.

Towards a conceptual framework demonstrating the effectiveness of audiovisual patient descriptions (patient video cases): a review of the current literature

PubMed Central

2012-01-01

Background Technological advances have enabled the widespread use of video cases via web-streaming and online download as an educational medium. The use of real subjects to demonstrate acute pathology should aid the education of health care professionals. However, the methodology by which this effect may be tested is not clear. Methods We undertook a literature review of major databases, found relevant articles relevant to using patient video cases as educational interventions, extracted the methodologies used and assessed these methods for internal and construct validity. Results A review of 2532 abstracts revealed 23 studies meeting the inclusion criteria and a final review of 18 of relevance. Medical students were the most commonly studied group (10 articles) with a spread of learner satisfaction, knowledge and behaviour tested. Only two of the studies fulfilled defined criteria on achieving internal and construct validity. The heterogeneity of articles meant it was not possible to perform any meta-analysis. Conclusions Previous studies have not well classified which facet of training or educational outcome the study is aiming to explore and had poor internal and construct validity. Future research should aim to validate a particular outcome measure, preferably by reproducing previous work rather than adopting new methods. In particular cognitive processing enhancement, demonstrated in a number of the medical student studies, should be tested at a postgraduate level. PMID:23256787

Long-Term Impact of Valid Case Criterion on Capturing Population-Level Growth under Item Response Theory Equating. Research Report. ETS RR-17-17

ERIC Educational Resources Information Center

Deng, Weiling; Monfils, Lora

2017-01-01

Using simulated data, this study examined the impact of different levels of stringency of the valid case inclusion criterion on item response theory (IRT)-based true score equating over 5 years in the context of K-12 assessment when growth in student achievement is expected. Findings indicate that the use of the most stringent inclusion criterion…

[DNA prints instead of plantar prints in neonatal identification].

PubMed

Rodríguez-Alarcón Gómez, J; Martińez de Pancorbo Gómez, M; Santillana Ferrer, L; Castro Espido, A; Melchor Maros, J C; Linares Uribe, M A; Fernández-Llebrez del Rey, L; Aranguren Dúo, G

1996-06-22

To check the possible usefulness in studying DNA in dried blood spots taken on filter paper blotters for newborn identification. It set out to establish: 1. The validity of the method for analysis; 2. The validity of all stored samples (such as those kept in clinical records); 3. Guarantee of non-intrusion in the genetic code; 4. Acceptable price and execution time. Forty (40) anonymous 13-year-old samples of 20 subjects (2 per subject) were studied. DNA was extracted using Chelex resin and the STR ("small tandem repeat") of microsatellite DNA was studies using the "polimerase chain reaction method" (PCR). Three non coding DNA loci (CSF1PO, TPOX and THO1) were analyzed by Multiplex amplification. It was possible to type 39 samples, making it possible to match the 20 cases (one by exclusion). The complete procedure yielded the results within 24 hours in all cases. The estimated final cost was found to be a fifth of that conventional maternity/paternity tests. The study carried out made matching possible in all 20 cases (directly in 19 cases). It was not necessary to study DNA coding areas. The validity of the method for analyzing samples stored for 13 years without any special care was also demonstrated. The technic was fast, producing the results within 24 hours, and at reasonable cost.

Validity of a PCR assay in CSF for the diagnosis of neurocysticercosis

PubMed Central

Campoverde, Alfredo; Romo, Matthew L.; García, Lorena; Piedra, Luis M.; Pacurucu, Mónica; López, Nelson; Aguilar, Jenner; López, Sebastian; Vintimilla, Luis C.; Toral, Ana M.; Peña-Tapia, Pablo

2017-01-01

Objective: To prospectively evaluate the validity of a PCR assay in CSF for the diagnosis of neurocysticercosis (NC). Methods: We conducted a multicenter, prospective case-control study, recruiting participants from 5 hospitals in Cuenca, Ecuador, from January 2015 to February 2016. Cases fulfilled validated diagnostic criteria for NC. For each case, a neurosurgical patient who did not fulfill the diagnostic criteria for NC was selected as a control. CT and MRI, as well as a CSF sample, were collected from both cases and controls. The diagnostic criteria to identify cases were used as a reference standard. Results: Overall, 36 case and 36 control participants were enrolled. PCR had a sensitivity of 72.2% (95% confidence interval [CI] 54.8%–85.8%) and a specificity of 100.0% (95% CI 90.3%–100.0%). For parenchymal NC, PCR had a sensitivity of 42.9% (95% CI 17.7%–71.1%), and for extraparenchymal NC, PCR had a sensitivity of 90.9% (95% CI 70.8%–98.9%). Conclusions: This study demonstrated the usefulness of this PCR assay in CSF for the diagnosis of NC. PCR may be particularly helpful for diagnosing extraparenchymal NC when neuroimaging techniques have failed. Classification of evidence: This study provides Class III evidence that CSF PCR can accurately identify patients with extraparenchymal NC. PMID:28105460

A Comparative Study of Adolescent Risk Assessment Instruments: Predictive and Incremental Validity

ERIC Educational Resources Information Center

Welsh, Jennifer L.; Schmidt, Fred; McKinnon, Lauren; Chattha, H. K.; Meyers, Joanna R.

2008-01-01

Promising new adolescent risk assessment tools are being incorporated into clinical practice but currently possess limited evidence of predictive validity regarding their individual and/or combined use in risk assessments. The current study compares three structured adolescent risk instruments, Youth Level of Service/Case Management Inventory…

A case of misdiagnosis of mild cognitive impairment: The utility of symptom validity testing in an outpatient memory clinic.

PubMed

Roor, Jeroen J; Dandachi-FitzGerald, Brechje; Ponds, Rudolf W H M

2016-01-01

Noncredible symptom reports hinder the diagnostic process. This fact is especially the case for medical conditions that rely on subjective report of symptoms instead of objective measures. Mild cognitive impairment (MCI) primarily relies on subjective report, which makes it potentially susceptible to erroneous diagnosis. In this case report, we describe a 59-year-old female patient diagnosed with MCI 10 years previously. The patient was referred to the neurology department for reexamination by her general practitioner because of cognitive complaints and persistent fatigue. This case study used information from the medical file, a new magnetic resonance imaging brain scan, and neuropsychological assessment. Current neuropsychological assessment, including symptom validity tests, clearly indicated noncredible test performance, thereby invalidating the obtained neuropsychological test data. We conclude that a blind spot for noncredible symptom reports existed in the previous diagnostic assessments. This case highlights the usefulness of formal symptom validity testing in the diagnostic assessment of MCI.

Validation of a computer case definition for sudden cardiac death in opioid users

PubMed Central

2012-01-01

Background To facilitate the use of automated databases for studies of sudden cardiac death, we previously developed a computerized case definition that had a positive predictive value between 86% and 88%. However, the definition has not been specifically validated for prescription opioid users, for whom out-of-hospital overdose deaths may be difficult to distinguish from sudden cardiac death. Findings We assembled a cohort of persons 30-74 years of age prescribed propoxyphene or hydrocodone who had no life-threatening non-cardiovascular illness, diagnosed drug abuse, residence in a nursing home in the past year, or hospital stay within the past 30 days. Medical records were sought for a sample of 140 cohort deaths within 30 days of a prescription fill meeting the computer case definition. Of the 140 sampled deaths, 81 were adjudicated; 73 (90%) were sudden cardiac deaths. Two deaths had possible opioid overdose; after removing these two the positive predictive value was 88%. Conclusions These findings are consistent with our previous validation studies and suggest the computer case definition of sudden cardiac death is a useful tool for pharmacoepidemiologic studies of opioid analgesics. PMID:22938531

A comparison of the validity of GHQ-12 and CHQ-12 in Chinese primary care patients in Manchester.

PubMed

Pan, P C; Goldberg, D P

1990-11-01

The present study compares the efficacy of the GHQ-12 and the Chinese Health Questionnaire (CHQ-12) in Cantonese speaking Chinese primary-care patients living in Greater Manchester, using relative operating characteristic (ROC) analysis. We did not find that the Chinese version offered any advantage over the conventional version of the GHQ in this population. Stepwise discriminant analysis however confirmed the value of individual items in the former pertaining to specific somatic symptoms and interpersonal relationships in differentiating cases from non-cases. Information biases, arising from the lack of a reliability study on the second-stage case identifying interview and the unique linguistic characteristics of the Chinese language may have affected the overall validity indices of the questionnaires. The study also examines the effects of using different criteria to define a case, and shows that with increasing levels of severity, there is an improvement in the diagnostic performance of the two questionnaires as reflected by areas under ROC curves and traditional validity indices. Possible explanations of these findings are discussed. The scoring method proposed by Goodchild & Duncan-Jones (1985) when used on these questionnaires had no demonstrable advantage over the conventional scoring method.

A computer case definition for sudden cardiac death.

PubMed

Chung, Cecilia P; Murray, Katherine T; Stein, C Michael; Hall, Kathi; Ray, Wayne A

2010-06-01

To facilitate studies of medications and sudden cardiac death, we developed and validated a computer case definition for these deaths. The study of community dwelling Tennessee Medicaid enrollees 30-74 years of age utilized a linked database with Medicaid inpatient/outpatient files, state death certificate files, and a state 'all-payers' hospital discharge file. The computerized case definition was developed from a retrospective cohort study of sudden cardiac deaths occurring between 1990 and 1993. Medical records for 926 potential cases had been adjudicated for this study to determine if they met the clinical definition for sudden cardiac death occurring in the community and were likely to be due to ventricular tachyarrhythmias. The computerized case definition included deaths with (1) no evidence of a terminal hospital admission/nursing home stay in any of the data sources; (2) an underlying cause of death code consistent with sudden cardiac death; and (3) no terminal procedures inconsistent with unresuscitated cardiac arrest. This definition was validated in an independent sample of 174 adjudicated deaths occurring between 1994 and 2005. The positive predictive value of the computer case definition was 86.0% in the development sample and 86.8% in the validation sample. The positive predictive value did not vary materially for deaths coded according to the ICO-9 (1994-1998, positive predictive value = 85.1%) or ICD-10 (1999-2005, 87.4%) systems. A computerized Medicaid database, linked with death certificate files and a state hospital discharge database, can be used for a computer case definition of sudden cardiac death. Copyright (c) 2009 John Wiley & Sons, Ltd.

Validation of Skills, Knowledge and Experience in Lifelong Learning in Europe

ERIC Educational Resources Information Center

Ogunleye, James

2012-01-01

The paper examines systems of validation of skills and experience as well as the main methods/tools currently used for validating skills and knowledge in lifelong learning. The paper uses mixed methods--a case study research and content analysis of European Union policy documents and frameworks--as a basis for this research. The selection of the…

Alternative Vocabularies in the Test Validity Literature

ERIC Educational Resources Information Center

Markus, Keith A.

2016-01-01

Justification of testing practice involves moving from one state of knowledge about the test to another. Theories of test validity can (a) focus on the beginning of the process, (b) focus on the end, or (c) encompass the entire process. Analyses of four case studies test and illustrate three claims: (a) restrictions on validity entail a supplement…

Validity and reliability of chronic tic disorder and obsessive-compulsive disorder diagnoses in the Swedish National Patient Register.

PubMed

Rück, Christian; Larsson, K Johan; Lind, Kristina; Perez-Vigil, Ana; Isomura, Kayoko; Sariaslan, Amir; Lichtenstein, Paul; Mataix-Cols, David

2015-06-22

The usefulness of cases diagnosed in administrative registers for research purposes is dependent on diagnostic validity. This study aimed to investigate the validity and inter-rater reliability of recorded diagnoses of tic disorders and obsessive-compulsive disorder (OCD) in the Swedish National Patient Register (NPR). Chart review of randomly selected register cases and controls. 100 tic disorder cases and 100 OCD cases were randomly selected from the NPR based on codes from the International Classification of Diseases (ICD) 8th, 9th and 10th editions, together with 50 epilepsy and 50 depression control cases. The obtained psychiatric records were blindly assessed by 2 senior psychiatrists according to the criteria of the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) and ICD-10. Positive predictive value (PPV; cases diagnosed correctly divided by the sum of true positives and false positives). Between 1969 and 2009, the NPR included 7286 tic disorder and 24,757 OCD cases. The vast majority (91.3% of tic cases and 80.1% of OCD cases) are coded with the most recent ICD version (ICD-10). For tic disorders, the PPV was high across all ICD versions (PPV=89% in ICD-8, 86% in ICD-9 and 97% in ICD-10). For OCD, only ICD-10 codes had high validity (PPV=91-96%). None of the epilepsy or depression control cases were wrongly diagnosed as having tic disorders or OCD, respectively. Inter-rater reliability was outstanding for both tic disorders (κ=1) and OCD (κ=0.98). The validity and reliability of ICD codes for tic disorders and OCD in the Swedish NPR is generally high. We propose simple algorithms to further increase the confidence in the validity of these codes for epidemiological research. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Optimal selection of markers for validation or replication from genome-wide association studies.

PubMed

Greenwood, Celia M T; Rangrej, Jagadish; Sun, Lei

2007-07-01

With reductions in genotyping costs and the fast pace of improvements in genotyping technology, it is not uncommon for the individuals in a single study to undergo genotyping using several different platforms, where each platform may contain different numbers of markers selected via different criteria. For example, a set of cases and controls may be genotyped at markers in a small set of carefully selected candidate genes, and shortly thereafter, the same cases and controls may be used for a genome-wide single nucleotide polymorphism (SNP) association study. After such initial investigations, often, a subset of "interesting" markers is selected for validation or replication. Specifically, by validation, we refer to the investigation of associations between the selected subset of markers and the disease in independent data. However, it is not obvious how to choose the best set of markers for this validation. There may be a prior expectation that some sets of genotyping data are more likely to contain real associations. For example, it may be more likely for markers in plausible candidate genes to show disease associations than markers in a genome-wide scan. Hence, it would be desirable to select proportionally more markers from the candidate gene set. When a fixed number of markers are selected for validation, we propose an approach for identifying an optimal marker-selection configuration by basing the approach on minimizing the stratified false discovery rate. We illustrate this approach using a case-control study of colorectal cancer from Ontario, Canada, and we show that this approach leads to substantial reductions in the estimated false discovery rates in the Ontario dataset for the selected markers, as well as reductions in the expected false discovery rates for the proposed validation dataset. Copyright 2007 Wiley-Liss, Inc.

Can jurors recognize missing control groups, confounds, and experimenter bias in psychological science?

PubMed

McAuliff, Bradley D; Kovera, Margaret Bull; Nunez, Gabriel

2009-06-01

This study examined the ability of jury-eligible community members (N = 248) to detect internal validity threats in psychological science presented during a trial. Participants read a case summary in which an expert testified about a study that varied in internal validity (valid, missing control group, confound, and experimenter bias) and ecological validity (high, low). Ratings of expert evidence quality and expert credibility were higher for the valid versus missing control group versions only. Internal validity did not influence verdict or ratings of plaintiff credibility and no differences emerged as a function of ecological validity. Expert evidence quality, expert credibility, and plaintiff credibility were positively correlated with verdict. Implications for the scientific reasoning literature and for trials containing psychological science are discussed.

Validation of self-reported start year of mobile phone use in a Swedish case-control study on radiofrequency fields and acoustic neuroma risk.

PubMed

Pettersson, David; Bottai, Matteo; Mathiesen, Tiit; Prochazka, Michaela; Feychting, Maria

2015-01-01

The possible effect of radiofrequency exposure from mobile phones on tumor risk has been studied since the late 1990s. Yet, empirical information about recall of the start of mobile phone use among adult cases and controls has never been reported. Limited knowledge about recall errors hampers interpretations of the epidemiological evidence. We used network operator data to validate the self-reported start year of mobile phone use in a case-control study of mobile phone use and acoustic neuroma risk. The answers of 96 (29%) cases and 111 (22%) controls could be included in the validation. The larger proportion of cases reflects a more complete and detailed reporting of subscription history. Misclassification was substantial, with large random errors, small systematic errors, and no significant differences between cases and controls. The average difference between self-reported and operator start year was -0.62 (95% confidence interval: -1.42, 0.17) years for cases and -0.71 (-1.50, 0.07) years for controls, standard deviations were 3.92 and 4.17 years, respectively. Agreement between self-reported and operator-recorded data categorized into short, intermediate and long-term use was moderate (kappa statistic: 0.42). Should an association exist, dilution of risk estimates and distortion of exposure-response patterns for time since first mobile phone use could result from the large random errors in self-reported start year. Retrospective collection of operator data likely leads to a selection of "good reporters", with a higher proportion of cases. Thus, differential recall cannot be entirely excluded.

Validation Test Report For The CRWMS Analysis and Logistics Visually Interactive Model Calvin Version 3.0, 10074-Vtr-3.0-00

DOE Office of Scientific and Technical Information (OSTI.GOV)

S. Gillespie

2000-07-27

This report describes the tests performed to validate the CRWMS ''Analysis and Logistics Visually Interactive'' Model (CALVIN) Version 3.0 (V3.0) computer code (STN: 10074-3.0-00). To validate the code, a series of test cases was developed in the CALVIN V3.0 Validation Test Plan (CRWMS M&O 1999a) that exercises the principal calculation models and options of CALVIN V3.0. Twenty-five test cases were developed: 18 logistics test cases and 7 cost test cases. These cases test the features of CALVIN in a sequential manner, so that the validation of each test case is used to demonstrate the accuracy of the input to subsequentmore » calculations. Where necessary, the test cases utilize reduced-size data tables to make the hand calculations used to verify the results more tractable, while still adequately testing the code's capabilities. Acceptance criteria, were established for the logistics and cost test cases in the Validation Test Plan (CRWMS M&O 1999a). The Logistics test cases were developed to test the following CALVIN calculation models: Spent nuclear fuel (SNF) and reactivity calculations; Options for altering reactor life; Adjustment of commercial SNF (CSNF) acceptance rates for fiscal year calculations and mid-year acceptance start; Fuel selection, transportation cask loading, and shipping to the Monitored Geologic Repository (MGR); Transportation cask shipping to and storage at an Interim Storage Facility (ISF); Reactor pool allocation options; and Disposal options at the MGR. Two types of cost test cases were developed: cases to validate the detailed transportation costs, and cases to validate the costs associated with the Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M&O) and Regional Servicing Contractors (RSCs). For each test case, values calculated using Microsoft Excel 97 worksheets were compared to CALVIN V3.0 scenarios with the same input data and assumptions. All of the test case results compare with the CALVIN V3.0 results within the bounds of the acceptance criteria. Therefore, it is concluded that the CALVIN V3.0 calculation models and options tested in this report are validated.« less

A verification library for multibody simulation software

NASA Technical Reports Server (NTRS)

Kim, Sung-Soo; Haug, Edward J.; Frisch, Harold P.

1989-01-01

A multibody dynamics verification library, that maintains and manages test and validation data is proposed, based on RRC Robot arm and CASE backhoe validation and a comparitive study of DADS, DISCOS, and CONTOPS that are existing public domain and commercial multibody dynamic simulation programs. Using simple representative problems, simulation results from each program are cross checked, and the validation results are presented. Functionalities of the verification library are defined, in order to automate validation procedure.

Assessing clinical competency in the health sciences

NASA Astrophysics Data System (ADS)

Panzarella, Karen Joanne

To test the success of integrated curricula in schools of health sciences, meaningful measurements of student performance are required to assess clinical competency. This research project analyzed a new performance assessment tool, the Integrated Standardized Patient Examination (ISPE), for assessing clinical competency: specifically, to assess Doctor of Physical Therapy (DPT) students' clinical competence as the ability to integrate basic science knowledge with clinical communication skills. Thirty-four DPT students performed two ISPE cases, one of a patient who sustained a stroke and the other a patient with a herniated lumbar disc. Cases were portrayed by standardized patients (SPs) in a simulated clinical setting. Each case was scored by an expert evaluator in the exam room and then by one investigator and the students themselves via videotape. The SPs scored each student on an overall encounter rubric. Written feedback was obtained from all participants in the study. Acceptable reliability was demonstrated via inter-rater agreement as well as inter-rater correlations on items that used a dichotomous scale, whereas the items requiring the use of the 4-point rubric were somewhat less reliable. For the entire scale both cases had a significant correlation between the Expert-Investigator pair of raters, for the CVA case r = .547, p < .05 and for the HD case r = .700, p < .01. The SPs scored students higher than the other raters. Students' self-assessments were most closely aligned with the investigator. Effects were apparent due to case. Content validity was gathered in the process of developing cases and patient scenarios that were used in this study. Construct validity was obtained from the survey results analyzed from the experts and students. Future studies should examine the effect of rater training upon the reliability. Criterion or predictive validity could be further studied by comparing students' performances on the ISPE with other independent estimates of students' competence. The unique integration questions of the ISPE were judged to have good content validity from experts and students, suggestive that integration, a most crucial element of clinical competence, while done in the mind of the student, can be practiced, learned and assessed.

The development and testing of a skin tear risk assessment tool.

PubMed

Newall, Nelly; Lewin, Gill F; Bulsara, Max K; Carville, Keryln J; Leslie, Gavin D; Roberts, Pam A

2017-02-01

The aim of the present study is to develop a reliable and valid skin tear risk assessment tool. The six characteristics identified in a previous case control study as constituting the best risk model for skin tear development were used to construct a risk assessment tool. The ability of the tool to predict skin tear development was then tested in a prospective study. Between August 2012 and September 2013, 1466 tertiary hospital patients were assessed at admission and followed up for 10 days to see if they developed a skin tear. The predictive validity of the tool was assessed using receiver operating characteristic (ROC) analysis. When the tool was found not to have performed as well as hoped, secondary analyses were performed to determine whether a potentially better performing risk model could be identified. The tool was found to have high sensitivity but low specificity and therefore have inadequate predictive validity. Secondary analysis of the combined data from this and the previous case control study identified an alternative better performing risk model. The tool developed and tested in this study was found to have inadequate predictive validity. The predictive validity of an alternative, more parsimonious model now needs to be tested. © 2015 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Initial Development and Validation of the Youth Internalizing Problems Screener

ERIC Educational Resources Information Center

Renshaw, Tyler L.; Cook, Clayton R.

2018-01-01

The present studies report on the initial development and validation of the Youth Internalizing Problems Screener (YIPS), which is a 10-item self-report rating scale for assessing general internalizing problems and identifying depression and anxiety caseness within the context of school mental health screening. Results from Study 1 (N = 177)…

Development and validation of an administrative case definition for inflammatory bowel diseases

PubMed Central

Rezaie, Ali; Quan, Hude; Fedorak, Richard N; Panaccione, Remo; Hilsden, Robert J

2012-01-01

BACKGROUND: A population-based database of inflammatory bowel disease (IBD) patients is invaluable to explore and monitor the epidemiology and outcome of the disease. In this context, an accurate and validated population-based case definition for IBD becomes critical for researchers and health care providers. METHODS: IBD and non-IBD individuals were identified through an endoscopy database in a western Canadian health region (Calgary Health Region, Calgary, Alberta). Subsequently, using a novel algorithm, a series of case definitions were developed to capture IBD cases in the administrative databases. In the second stage of the study, the criteria were validated in the Capital Health Region (Edmonton, Alberta). RESULTS: A total of 150 IBD case definitions were developed using 1399 IBD patients and 15,439 controls in the development phase. In the validation phase, 318,382 endoscopic procedures were searched and 5201 IBD patients were identified. After consideration of sensitivity, specificity and temporal stability of each validated case definition, a diagnosis of IBD was assigned to individuals who experienced at least two hospitalizations or had four physician claims, or two medical contacts in the Ambulatory Care Classification System database with an IBD diagnostic code within a two-year period (specificity 99.8%; sensitivity 83.4%; positive predictive value 97.4%; negative predictive value 98.5%). An alternative case definition was developed for regions without access to the Ambulatory Care Classification System database. A novel scoring system was developed that detected Crohn disease and ulcerative colitis patients with a specificity of >99% and a sensitivity of 99.1% and 86.3%, respectively. CONCLUSION: Through a robust methodology, a reproducible set of criteria to capture IBD patients through administrative databases was developed. The methodology may be used to develop similar administrative definitions for chronic diseases. PMID:23061064

Factor Validity of the Motivated Strategies for Learning Questionnaire (MSLQ) in Asynchronous Online Learning Environments (AOLE)

ERIC Educational Resources Information Center

Cho, Moon-Heum; Summers, Jessica

2012-01-01

The purpose of this study was to investigate the factor validity of the Motivated Strategies for Learning Questionnaire (MSLQ) in asynchronous online learning environments. In order to check the factor validity, confirmatory factor analysis (CFA) was conducted with 193 cases. Using CFA, it was found that the original measurement model fit for…

Proposed epidemiological case definition for serious skin infection in children.

PubMed

O'Sullivan, Cathryn E; Baker, Michael G

2010-04-01

Researching the rising incidence of serious skin infections in children is limited by the lack of a consistent and valid case definition. We aimed to develop and evaluate a good quality case definition, for use in future research and surveillance of these infections. We tested the validity of the existing case definition, and then of 11 proposed alternative definitions, by assessing their screening performance when applied to a population of paediatric skin infection cases identified by a chart review of 4 years of admissions to a New Zealand hospital. Previous studies have largely used definitions based on the International Classification of Diseases skin infection subchapter. This definition is highly specific (100%) but poorly sensitive (61%); it fails to capture skin infections of atypical anatomical sites, those secondary to primary skin disease and trauma, and those recorded as additional diagnoses. Including these groups produced a new case definition with 98.9% sensitivity and 98.8% specificity. Previous analyses of serious skin infection in children have underestimated the true burden of disease. Using this proposed broader case definition should allow future researchers to produce more valid and comparable estimates of the true burden of these important and increasing infections.

A multisite validation of whole slide imaging for primary diagnosis using standardized data collection and analysis.

PubMed

Wack, Katy; Drogowski, Laura; Treloar, Murray; Evans, Andrew; Ho, Jonhan; Parwani, Anil; Montalto, Michael C

2016-01-01

Text-based reporting and manual arbitration for whole slide imaging (WSI) validation studies are labor intensive and do not allow for consistent, scalable, and repeatable data collection or analysis. The objective of this study was to establish a method of data capture and analysis using standardized codified checklists and predetermined synoptic discordance tables and to use these methods in a pilot multisite validation study. Fifteen case report form checklists were generated from the College of American Pathology cancer protocols. Prior to data collection, all hypothetical pairwise comparisons were generated, and a level of harm was determined for each possible discordance. Four sites with four pathologists each generated 264 independent reads of 33 cases. Preestablished discordance tables were applied to determine site by site and pooled accuracy, intrareader/intramodality, and interreader intramodality error rates. Over 10,000 hypothetical pairwise comparisons were evaluated and assigned harm in discordance tables. The average difference in error rates between WSI and glass, as compared to ground truth, was 0.75% with a lower bound of 3.23% (95% confidence interval). Major discordances occurred on challenging cases, regardless of modality. The average inter-reader agreement across sites for glass was 76.5% (weighted kappa of 0.68) and for digital it was 79.1% (weighted kappa of 0.72). These results demonstrate the feasibility and utility of employing standardized synoptic checklists and predetermined discordance tables to gather consistent, comprehensive diagnostic data for WSI validation studies. This method of data capture and analysis can be applied in large-scale multisite WSI validations.

Reliability and validity: Part II.

PubMed

Davis, Debora Winders

2004-01-01

Determining measurement reliability and validity involves complex processes. There is usually room for argument about most instruments. It is important that the researcher clearly describes the processes upon which she made the decision to use a particular instrument, and presents the evidence available showing that the instrument is reliable and valid for the current purposes. In some cases, the researcher may need to conduct pilot studies to obtain evidence upon which to decide whether the instrument is valid for a new population or a different setting. In all cases, the researcher must present a clear and complete explanation for the choices, she has made regarding reliability and validity. The consumer must then judge the degree to which the researcher has provided adequate and theoretically sound rationale. Although I have tried to touch on most of the important concepts related to measurement reliability and validity, it is beyond the scope of this column to be exhaustive. There are textbooks devoted entirely to specific measurement issues if readers require more in-depth knowledge.

Analysis of risk factors for schizophrenia with two different case definitions: a nationwide register-based external validation study.

PubMed

Sørensen, Holger J; Larsen, Janne T; Mors, Ole; Nordentoft, Merete; Mortensen, Preben B; Petersen, Liselotte

2015-03-01

Different case definitions of schizophrenia have been used in register based research. However, no previous study has externally validated two different case definitions of schizophrenia against a wide range of risk factors for schizophrenia. We investigated hazard ratios (HRs) for a wide range of risk factors for ICD-10 DCR schizophrenia using a nationwide Danish sample of 2,772,144 residents born in 1955-1997. We compared one contact only (OCO) (the case definition of schizophrenia used in Danish register based studies) with two or more contacts (TMC) (a case definition of at least 2 inpatient contacts with schizophrenia). During the follow-up, the OCO definition included 15,074 and the TMC 7562 cases; i.e. half as many. The TMC case definition appeared to select for a worse illness course. A wide range of risk factors were uniformly associated with both case definitions and only slightly higher risk estimates were found for the TMC definition. Choosing at least 2 inpatient contacts with schizophrenia (TMC) instead of the currently used case definition would result in almost similar risk estimates for many well-established risk factors. However, this would also introduce selection and include considerably fewer cases and reduce power of e.g. genetic studies based on register-diagnosed cases only. Copyright © 2015 Elsevier B.V. All rights reserved.

Criterion validity and clinical usefulness of Attention Deficit Hyperactivity Disorder Rating Scale IV in attention deficit hyperactivity disorder (ADHD) as a function of method and age.

PubMed

López-Villalobos, José A; Andrés-De Llano, Jesús; López-Sánchez, María V; Rodríguez-Molinero, Luis; Garrido-Redondo, Mercedes; Sacristán-Martín, Ana M; Martínez-Rivera, María T; Alberola-López, Susana

2017-02-01

The aim of this research is to analyze Attention Deficit Hyperactivity Disorder Rating Scales IV (ADHD RS-IV) criteria validity and its clinical usefulness for the assessment of Attention Deficit Hyperactivity Disorder (ADHD) as a function of assessment method and age. A sample was obtained from an epidemiological study (n = 1095, 6-16 years). Clinical cases of ADHD  (ADHD-CL) were selected by dimensional ADHD RS-IV and later by clinical interview (DSM-IV). ADHD-CL cases were compared with four categorical results of ADHD RS-IV provided by parents (CATPA), teachers (CATPR), either parents or teachers (CATPAOPR) and both parents and teachers (CATPA&PR). Criterion validity and clinical usefulness of the answer modalities to ADHD RS-IV were studied. ADHD-CL rate was 6.9% in childhood, 6.2% in preadolescence and 6.9% in adolescence. Alternative methods to the clinical interview led to increased numbers of ADHD cases in all age groups analyzed, in the following sequence: CATPAOPR> CATPRO> CATPA> CATPA&PR> ADHD-CL. CATPA&PR was the procedure with the greatest validity, specificity and clinical usefulness in all three age groups, particularly in the childhood. Isolated use of ADHD RS-IV leads to an increase in ADHD cases compared to clinical interview, and varies depending on the procedure used.

A computable phenotype for asthma case identification in adult and pediatric patients: External validation in the Chicago Area Patient-Outcomes Research Network (CAPriCORN).

PubMed

Afshar, Majid; Press, Valerie G; Robison, Rachel G; Kho, Abel N; Bandi, Sindhura; Biswas, Ashvini; Avila, Pedro C; Kumar, Harsha Vardhan Madan; Yu, Byung; Naureckas, Edward T; Nyenhuis, Sharmilee M; Codispoti, Christopher D

2017-10-13

Comprehensive, rapid, and accurate identification of patients with asthma for clinical care and engagement in research efforts is needed. The original development and validation of a computable phenotype for asthma case identification occurred at a single institution in Chicago and demonstrated excellent test characteristics. However, its application in a diverse payer mix, across different health systems and multiple electronic health record vendors, and in both children and adults was not examined. The objective of this study is to externally validate the computable phenotype across diverse Chicago institutions to accurately identify pediatric and adult patients with asthma. A cohort of 900 asthma and control patients was identified from the electronic health record between January 1, 2012 and November 30, 2014. Two physicians at each site independently reviewed the patient chart to annotate cases. The inter-observer reliability between the physician reviewers had a κ-coefficient of 0.95 (95% CI 0.93-0.97). The accuracy, sensitivity, specificity, negative predictive value, and positive predictive value of the computable phenotype were all above 94% in the full cohort. The excellent positive and negative predictive values in this multi-center external validation study establish a useful tool to identify asthma cases in in the electronic health record for research and care. This computable phenotype could be used in large-scale comparative-effectiveness trials.

Development and validation of a scoring index to predict the presence of lesions in capsule endoscopy in patients with suspected Crohn's disease of the small bowel: a Spanish multicenter study.

PubMed

Egea-Valenzuela, Juan; González Suárez, Begoña; Sierra Bernal, Cristian; Juanmartiñena Fernández, José Francisco; Luján-Sanchís, Marisol; San Juan Acosta, Mileidis; Martínez Andrés, Blanca; Pons Beltrán, Vicente; Sastre Lozano, Violeta; Carretero Ribón, Cristina; de Vera Almenar, Félix; Sánchez Cuenca, Joaquín; Alberca de Las Parras, Fernando; Rodríguez de Miguel, Cristina; Valle Muñoz, Julio; Férnandez-Urién Sainz, Ignacio; Torres González, Carolina; Borque Barrera, Pilar; Pérez-Cuadrado Robles, Enrique; Alonso Lázaro, Noelia; Martínez García, Pilar; Prieto de Frías, César; Carballo Álvarez, Fernando

2018-05-01

Capsule endoscopy (CE) is the first-line investigation in cases of suspected Crohn's disease (CD) of the small bowel, but the factors associated with a higher diagnostic yield remain unclear. Our aim is to develop and validate a scoring index to assess the risk of the patients in this setting on the basis of biomarkers. Data on fecal calprotectin, C-reactive protein, and other biomarkers from a population of 124 patients with suspected CD of the small bowel studied by CE and included in a PhD study were used to build a scoring index. This was first used on this population (internal validation process) and after that on a different set of patients from a multicenter study (external validation process). An index was designed in which every biomarker is assigned a score. Three risk groups have been established (low, intermediate, and high). In the internal validation analysis (124 individuals), patients had a 10, 46.5, and 81% probability of showing inflammatory lesions in CE in the low-risk, intermediate-risk, and high-risk groups, respectively. In the external validation analysis, including 410 patients from 12 Spanish hospitals, this probability was 15.8, 49.7, and 80.6% for the low-risk, intermediate-risk, and high-risk groups, respectively. Results from the internal validation process show that the scoring index is coherent, and results from the external validation process confirm its reliability. This index can be a useful tool for selecting patients before CE studies in cases of suspected CD of the small bowel.

Violent Crime in Post-Civil War Guatemala: Causes and Policy Implications

DTIC Science & Technology

2015-03-01

on field research and case studies in Honduras, Bolivia, and Argentina. Bailey’s Security Trap theory is comprehensive in nature and derived from... research question. The second phase uses empirical data and comparative case studies to validate or challenge selected arguments that potentially...Contextual relevancy, historical inference, Tools: Empirics and case conclusions empirical data studies Figme2. Sample Research Methodology E

Does case misclassification threaten the validity of studies investigating the relationship between neck manipulation and vertebral artery dissection stroke? Yes.

PubMed

Paulus, Jessica K; Thaler, David E

2016-01-01

For patients and health care providers who are considering spinal manipulative therapy of the neck, it is crucial to establish if it is a trigger for cervical artery dissection and/or stroke, and if it is, the magnitude of the risk. We discuss the biological plausibility of how neck manipulation could cause cervical artery dissection. We also discuss how case misclassification threatens the validity of influential published studies that have investigated the relationship between neck manipulation and dissection. Our position is supported by the fact that the largest epidemiologic studies of neck manipulation safety with respect to neurological outcomes have relied on International Classification of Diseases-9 codes for case identification. However, the application of these codes in prior studies failed to identify dissections (rather than strokes in general) and so conclusions from those studies are invalid. There are several methodological challenges to understanding the association between neck manipulation and vertebral artery dissection. Addressing these issues is critical because even a modest association between neck manipulation and cervical artery dissection could translate into a significant number of avoidable dissections given the widespread use of neck manipulation by providers from various backgrounds. We believe that valid case classification, accurate measurement of manipulative procedures, and addressing reverse causation bias should be top priorities for future research.

Validation of the 'United Registries for Clinical Assessment and Research' [UR-CARE], a European Online Registry for Clinical Care and Research in Inflammatory Bowel Disease.

PubMed

Burisch, Johan; Gisbert, Javier P; Siegmund, Britta; Bettenworth, Dominik; Thomsen, Sandra Bohn; Cleynen, Isabelle; Cremer, Anneline; Ding, Nik John Sheng; Furfaro, Federica; Galanopoulos, Michail; Grunert, Philip Christian; Hanzel, Jurij; Ivanovski, Tamara Knezevic; Krustins, Eduards; Noor, Nurulamin; O'Morain, Neil; Rodríguez-Lago, Iago; Scharl, Michael; Tua, Julia; Uzzan, Mathieu; Ali Yassin, Nuha; Baert, Filip; Langholz, Ebbe

2018-04-27

The 'United Registries for Clinical Assessment and Research' [UR-CARE] database is an initiative of the European Crohn's and Colitis Organisation [ECCO] to facilitate daily patient care and research studies in inflammatory bowel disease [IBD]. Herein, we sought to validate the database by using fictional case histories of patients with IBD that were to be entered by observers of varying experience in IBD. Nineteen observers entered five patient case histories into the database. After 6 weeks, all observers entered the same case histories again. For each case history, 20 key variables were selected to calculate the accuracy for each observer. We assumed that the database was such that ≥ 90% of the entered data would be correct. The overall proportion of correctly entered data was calculated using a beta-binomial regression model to account for inter-observer variation and compared to the expected level of validity. Re-test reliability was assessed using McNemar's test. For all case histories, the overall proportion of correctly entered items and their confidence intervals included the target of 90% (Case 1: 92% [88-94%]; Case 2: 87% [83-91%]; Case 3: 93% [90-95%]; Case 4: 97% [94-99%]; Case 5: 91% [87-93%]). These numbers did not differ significantly from those found 6 weeks later [NcNemar's test p > 0.05]. The UR-CARE database appears to be feasible, valid and reliable as a tool and easy to use regardless of prior user experience and level of clinical IBD experience. UR-CARE has the potential to enhance future European collaborations regarding clinical research in IBD.

Model-based methods for case definitions from administrative health data: application to rheumatoid arthritis

PubMed Central

Kroeker, Kristine; Widdifield, Jessica; Muthukumarana, Saman; Jiang, Depeng; Lix, Lisa M

2017-01-01

Objective This research proposes a model-based method to facilitate the selection of disease case definitions from validation studies for administrative health data. The method is demonstrated for a rheumatoid arthritis (RA) validation study. Study design and setting Data were from 148 definitions to ascertain cases of RA in hospital, physician and prescription medication administrative data. We considered: (A) separate univariate models for sensitivity and specificity, (B) univariate model for Youden’s summary index and (C) bivariate (ie, joint) mixed-effects model for sensitivity and specificity. Model covariates included the number of diagnoses in physician, hospital and emergency department records, physician diagnosis observation time, duration of time between physician diagnoses and number of RA-related prescription medication records. Results The most common case definition attributes were: 1+ hospital diagnosis (65%), 2+ physician diagnoses (43%), 1+ specialist physician diagnosis (51%) and 2+ years of physician diagnosis observation time (27%). Statistically significant improvements in sensitivity and/or specificity for separate univariate models were associated with (all p values <0.01): 2+ and 3+ physician diagnoses, unlimited physician diagnosis observation time, 1+ specialist physician diagnosis and 1+ RA-related prescription medication records (65+ years only). The bivariate model produced similar results. Youden’s index was associated with these same case definition criteria, except for the length of the physician diagnosis observation time. Conclusion A model-based method provides valuable empirical evidence to aid in selecting a definition(s) for ascertaining diagnosed disease cases from administrative health data. The choice between univariate and bivariate models depends on the goals of the validation study and number of case definitions. PMID:28645978

Assessing Procedural Competence: Validity Considerations.

PubMed

Pugh, Debra M; Wood, Timothy J; Boulet, John R

2015-10-01

Simulation-based medical education (SBME) offers opportunities for trainees to learn how to perform procedures and to be assessed in a safe environment. However, SBME research studies often lack robust evidence to support the validity of the interpretation of the results obtained from tools used to assess trainees' skills. The purpose of this paper is to describe how a validity framework can be applied when reporting and interpreting the results of a simulation-based assessment of skills related to performing procedures. The authors discuss various sources of validity evidence because they relate to SBME. A case study is presented.

Evaluating physician performance at individualizing care: a pilot study tracking contextual errors in medical decision making.

PubMed

Weiner, Saul J; Schwartz, Alan; Yudkowsky, Rachel; Schiff, Gordon D; Weaver, Frances M; Goldberg, Julie; Weiss, Kevin B

2007-01-01

Clinical decision making requires 2 distinct cognitive skills: the ability to classify patients' conditions into diagnostic and management categories that permit the application of research evidence and the ability to individualize or-more specifically-to contextualize care for patients whose circumstances and needs require variation from the standard approach to care. The purpose of this study was to develop and test a methodology for measuring physicians' performance at contextualizing care and compare it to their performance at planning biomedically appropriate care. First, the authors drafted 3 cases, each with 4 variations, 3 of which are embedded with biomedical and/or contextual information that is essential to planning care. Once the cases were validated as instruments for assessing physician performance, 54 internal medicine residents were then presented with opportunities to make these preidentified biomedical or contextual errors, and data were collected on information elicitation and error making. The case validation process was successful in that, in the final iteration, the physicians who received the contextual variant of cases proposed an alternate plan of care to those who received the baseline variant 100% of the time. The subsequent piloting of these validated cases unmasked previously unmeasured differences in physician performance at contextualizing care. The findings, which reflect the performance characteristics of the study population, are presented. This pilot study demonstrates a methodology for measuring physician performance at contextualizing care and illustrates the contribution of such information to an overall assessment of physician practice.

Validation of the Italian Version of the Caregiver Abuse Screen among Family Caregivers of Older People with Alzheimer's Disease.

PubMed

Melchiorre, Maria Gabriella; Di Rosa, Mirko; Barbabella, Francesco; Barbini, Norma; Lattanzio, Fabrizia; Chiatti, Carlos

2017-01-01

Introduction . Elder abuse is often a hidden phenomenon and, in many cases, screening practices are difficult to implement among older people with dementia. The Caregiver Abuse Screen (CASE) is a useful tool which is administered to family caregivers for detecting their potential abusive behavior. Objectives . To validate the Italian version of the CASE tool in the context of family caregiving of older people with Alzheimer's disease (AD) and to identify risk factors for elder abuse in Italy. Methods . The CASE test was administered to 438 caregivers, recruited in the Up-Tech study. Validity and reliability were evaluated using Spearman's correlation coefficients, principal-component analysis, and Cronbach's alphas. The association between the CASE and other variables potentially associated with elder abuse was also analyzed. Results . The factor analysis suggested the presence of a single factor, with a strong internal consistency (Cronbach's alpha = 0.86). CASE score was strongly correlated with well-known risk factors of abuse. At multivariate level, main factors associated with CASE total score were caregiver burden and AD-related behavioral disturbances. Conclusions . The Italian version of the CASE is a reliable and consistent screening tool for tackling the risk of being or becoming perpetrators of abuse by family caregivers of people with AD.

Validation of the Italian Version of the Caregiver Abuse Screen among Family Caregivers of Older People with Alzheimer's Disease

PubMed Central

Di Rosa, Mirko; Barbabella, Francesco; Barbini, Norma; Chiatti, Carlos

2017-01-01

Introduction. Elder abuse is often a hidden phenomenon and, in many cases, screening practices are difficult to implement among older people with dementia. The Caregiver Abuse Screen (CASE) is a useful tool which is administered to family caregivers for detecting their potential abusive behavior. Objectives. To validate the Italian version of the CASE tool in the context of family caregiving of older people with Alzheimer's disease (AD) and to identify risk factors for elder abuse in Italy. Methods. The CASE test was administered to 438 caregivers, recruited in the Up-Tech study. Validity and reliability were evaluated using Spearman's correlation coefficients, principal-component analysis, and Cronbach's alphas. The association between the CASE and other variables potentially associated with elder abuse was also analyzed. Results. The factor analysis suggested the presence of a single factor, with a strong internal consistency (Cronbach's alpha = 0.86). CASE score was strongly correlated with well-known risk factors of abuse. At multivariate level, main factors associated with CASE total score were caregiver burden and AD-related behavioral disturbances. Conclusions. The Italian version of the CASE is a reliable and consistent screening tool for tackling the risk of being or becoming perpetrators of abuse by family caregivers of people with AD. PMID:28265571

Updating the OMERACT filter: implications of filter 2.0 to select outcome instruments through assessment of "truth": content, face, and construct validity.

PubMed

Tugwell, Peter; Boers, Maarten; D'Agostino, Maria-Antonietta; Beaton, Dorcas; Boonen, Annelies; Bingham, Clifton O; Choy, Ernest; Conaghan, Philip G; Dougados, Maxime; Duarte, Catia; Furst, Daniel E; Guillemin, Francis; Gossec, Laure; Heiberg, Turid; van der Heijde, Désirée M; Hewlett, Sarah; Kirwan, John R; Kvien, Tore K; Landewé, Robert B; Mease, Philip J; Østergaard, Mikkel; Simon, Lee; Singh, Jasvinder A; Strand, Vibeke; Wells, George

2014-05-01

The Outcome Measures in Rheumatology (OMERACT) Filter provides guidelines for the development and validation of outcome measures for use in clinical research. The "Truth" section of the OMERACT Filter requires that criteria be met to demonstrate that the outcome instrument meets the criteria for content, face, and construct validity. Discussion groups critically reviewed a variety of ways in which case studies of current OMERACT Working Groups complied with the Truth component of the Filter and what issues remained to be resolved. The case studies showed that there is broad agreement on criteria for meeting the Truth criteria through demonstration of content, face, and construct validity; however, several issues were identified that the Filter Working Group will need to address. These issues will require resolution to reach consensus on how Truth will be assessed for the proposed Filter 2.0 framework, for instruments to be endorsed by OMERACT.

Predictive validity of the Biomedical Admissions Test: an evaluation and case study.

PubMed

McManus, I C; Ferguson, Eamonn; Wakeford, Richard; Powis, David; James, David

2011-01-01

There has been an increase in the use of pre-admission selection tests for medicine. Such tests need to show good psychometric properties. Here, we use a paper by Emery and Bell [2009. The predictive validity of the Biomedical Admissions Test for pre-clinical examination performance. Med Educ 43:557-564] as a case study to evaluate and comment on the reporting of psychometric data in the field of medical student selection (and the comments apply to many papers in the field). We highlight pitfalls when reliability data are not presented, how simple zero-order associations can lead to inaccurate conclusions about the predictive validity of a test, and how biases need to be explored and reported. We show with BMAT that it is the knowledge part of the test which does all the predictive work. We show that without evidence of incremental validity it is difficult to assess the value of any selection tests for medicine.

Better cancer biomarker discovery through better study design.

PubMed

Rundle, Andrew; Ahsan, Habibul; Vineis, Paolo

2012-12-01

High-throughput laboratory technologies coupled with sophisticated bioinformatics algorithms have tremendous potential for discovering novel biomarkers, or profiles of biomarkers, that could serve as predictors of disease risk, response to treatment or prognosis. We discuss methodological issues in wedding high-throughput approaches for biomarker discovery with the case-control study designs typically used in biomarker discovery studies, especially focusing on nested case-control designs. We review principles for nested case-control study design in relation to biomarker discovery studies and describe how the efficiency of biomarker discovery can be effected by study design choices. We develop a simulated prostate cancer cohort data set and a series of biomarker discovery case-control studies nested within the cohort to illustrate how study design choices can influence biomarker discovery process. Common elements of nested case-control design, incidence density sampling and matching of controls to cases are not typically factored correctly into biomarker discovery analyses, inducing bias in the discovery process. We illustrate how incidence density sampling and matching of controls to cases reduce the apparent specificity of truly valid biomarkers 'discovered' in a nested case-control study. We also propose and demonstrate a new case-control matching protocol, we call 'antimatching', that improves the efficiency of biomarker discovery studies. For a valid, but as yet undiscovered, biomarker(s) disjunctions between correctly designed epidemiologic studies and the practice of biomarker discovery reduce the likelihood that true biomarker(s) will be discovered and increases the false-positive discovery rate. © 2012 The Authors. European Journal of Clinical Investigation © 2012 Stichting European Society for Clinical Investigation Journal Foundation.

The risk of acute liver injury associated with the use of antibiotics--evaluating robustness of results in the pharmacoepidemiological research on outcomes of therapeutics by a European consortium (PROTECT) project.

PubMed

Udo, Renate; Tcherny-Lessenot, Stéphanie; Brauer, Ruth; Dolin, Paul; Irvine, David; Wang, Yunxun; Auclert, Laurent; Juhaeri, Juhaeri; Kurz, Xavier; Abenhaim, Lucien; Grimaldi, Lamiae; De Bruin, Marie L

2016-03-01

To examine the robustness of findings of case-control studies on the association between acute liver injury (ALI) and antibiotic use in the following different situations: (i) Replication of a protocol in different databases, with different data types, as well as replication in the same database, but performed by a different research team. (ii) Varying algorithms to identify cases, with and without manual case validation. (iii) Different exposure windows for time at risk. Five case-control studies in four different databases were performed with a common study protocol as starting point to harmonize study outcome definitions, exposure definitions and statistical analyses. All five studies showed an increased risk of ALI associated with antibiotic use ranging from OR 2.6 (95% CI 1.3-5.4) to 7.7 (95% CI 2.0-29.3). Comparable trends could be observed in the five studies: (i) without manual validation the use of the narrowest definition for ALI showed higher risk estimates, (ii) narrow and broad algorithm definitions followed by manual validation of cases resulted in similar risk estimates, and (iii) the use of a larger window (30 days vs 14 days) to define time at risk led to a decrease in risk estimates. Reproduction of a study using a predefined protocol in different database settings is feasible, although assumptions had to be made and amendments in the protocol were inevitable. Despite differences, the strength of association was comparable between the studies. In addition, the impact of varying outcome definitions and time windows showed similar trends within the data sources. Copyright © 2015 John Wiley & Sons, Ltd.

Validation of asthma recording in electronic health records: protocol for a systematic review.

PubMed

Nissen, Francis; Quint, Jennifer K; Wilkinson, Samantha; Mullerova, Hana; Smeeth, Liam; Douglas, Ian J

2017-05-29

Asthma is a common, heterogeneous disease with significant morbidity and mortality worldwide. It can be difficult to define in epidemiological studies using electronic health records as the diagnosis is based on non-specific respiratory symptoms and spirometry, neither of which are routinely registered. Electronic health records can nonetheless be valuable to study the epidemiology, management, healthcare use and control of asthma. For health databases to be useful sources of information, asthma diagnoses should ideally be validated. The primary objectives are to provide an overview of the methods used to validate asthma diagnoses in electronic health records and summarise the results of the validation studies. EMBASE and MEDLINE will be systematically searched for appropriate search terms. The searches will cover all studies in these databases up to October 2016 with no start date and will yield studies that have validated algorithms or codes for the diagnosis of asthma in electronic health records. At least one test validation measure (sensitivity, specificity, positive predictive value, negative predictive value or other) is necessary for inclusion. In addition, we require the validated algorithms to be compared with an external golden standard, such as a manual review, a questionnaire or an independent second database. We will summarise key data including author, year of publication, country, time period, date, data source, population, case characteristics, clinical events, algorithms, gold standard and validation statistics in a uniform table. This study is a synthesis of previously published studies and, therefore, no ethical approval is required. The results will be submitted to a peer-reviewed journal for publication. Results from this systematic review can be used to study outcome research on asthma and can be used to identify case definitions for asthma. CRD42016041798. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Validation and utilization of a TFE3 break-apart FISH assay for Xp11.2 translocation renal cell carcinoma and alveolar soft part sarcoma.

PubMed

Pradhan, Dinesh; Roy, Somak; Quiroga-Garza, Gabriela; Cieply, Kathleen; Mahaffey, Alyssa L; Bastacky, Sheldon; Dhir, Rajiv; Parwani, Anil V

2015-09-29

Xp11.2 or TFE3 translocation renal cell carcinomas (RCC) and alveolar soft part sarcoma (ASPS) are characterized by chromosome translocations involving the Xp11.2 breakpoint resulting in transcription factor TFE3 gene fusions. The most common translocations documented in TFE3 RCCs are t(X;1) (p11.2;q21) and t(X;17) (p11.2;q25) which leads to fusion of TFE3 gene on Xp11.2 with PRCC or ASPL respectively. TFE3 immunohistochemistry (IHC) has been inconsistent over time due to background staining problems in part related to fixation issues. Karyotyping to detect TFE3 gene rearrangement requires typically unavailable fresh tissue. Reverse transcriptase-polymerase chain reaction (RT-PCR) is generally very challenging due to degradation of RNA in archival material. The study objective was to develop and validate a TFE3 break-apart fluorescence in situ hybridization (FISH) assay to confirm Xp11 translocation RCCs and ASPS. Representative sections of formalin-fixed paraffin-embedded tissue blocks were selected in 40 possible cases. Approximately 60 tumor cells were analyzed in the targeted region. The validation of TFE3 FISH was done with 11 negative and two positive cases. Cut off for a positive result was validated as >7.15 % positive nuclei with any pattern of break-apart signals. FISH evaluation was done blinded of the immunohistochemical or karyotype data. Three out of forty cases were positive for the TFE3 break-apart signals by FISH. The negative cases were reported as clear cell RCC with papillary features (10), clear cell RCC with sarcomatoid areas (2), Papillary RCC with clear cell areas (9), Chromophobe RCC (2), RCC, unclassified type (3) and renal medullary carcinoma (1). 3 of the negative cases were consultation cases for renal tumor with unknown histology. Seven negative cases were soft tissue tumor suspicious for ASPS. Our study validates the utility of TFE3 break-apart FISH on formalin-fixed paraffin-embedded tissue sections for diagnosis and confirmation of Xp11.2 translocation RCCs and ASPS.

Simulation verification techniques study: Simulation performance validation techniques document. [for the space shuttle system

NASA Technical Reports Server (NTRS)

Duncan, L. M.; Reddell, J. P.; Schoonmaker, P. B.

1975-01-01

Techniques and support software for the efficient performance of simulation validation are discussed. Overall validation software structure, the performance of validation at various levels of simulation integration, guidelines for check case formulation, methods for real time acquisition and formatting of data from an all up operational simulator, and methods and criteria for comparison and evaluation of simulation data are included. Vehicle subsystems modules, module integration, special test requirements, and reference data formats are also described.

Generalisability of vaccine effectiveness estimates: an analysis of cases included in a postlicensure evaluation of 13-valent pneumococcal conjugate vaccine in the USA

PubMed Central

Link-Gelles, Ruth; Westreich, Daniel; Aiello, Allison E; Shang, Nong; Weber, David J; Rosen, Jennifer B; Motala, Tasneem; Mascola, Laurene; Eason, Jeffery; Scherzinger, Karen; Holtzman, Corinne; Reingold, Arthur L; Barnes, Meghan; Petit, Susan; Farley, Monica M; Harrison, Lee H; Zansky, Shelley; Thomas, Ann; Schaffner, William; McGee, Lesley; Whitney, Cynthia G; Moore, Matthew R

2017-01-01

Objectives External validity, or generalisability, is the measure of how well results from a study pertain to individuals in the target population. We assessed generalisability, with respect to socioeconomic status, of estimates from a matched case–control study of 13-valent pneumococcal conjugate vaccine effectiveness for the prevention of invasive pneumococcal disease in children in the USA. Design Matched case–control study. Setting Thirteen active surveillance sites for invasive pneumococcal disease in the USA. Participants Cases were identified from active surveillance and controls were age and zip code matched. Outcome measures Socioeconomic status was assessed at the individual level via parent interview (for enrolled individuals only) and birth certificate data (for both enrolled and unenrolled individuals) and at the neighbourhood level by geocoding to the census tract (for both enrolled and unenrolled individuals). Prediction models were used to determine if socioeconomic status was associated with enrolment. Results We enrolled 54.6% of 1211 eligible cases and found a trend toward enrolled cases being more affluent than unenrolled cases. Enrolled cases were slightly more likely to have private insurance at birth (p=0.08) and have mothers with at least some college education (p<0.01). Enrolled cases also tended to come from more affluent census tracts. Despite these differences, our best predictive model for enrolment yielded a concordance statistic of only 0.703, indicating mediocre predictive value. Variables retained in the final model were assessed for effect measure modification, and none were found to be significant modifiers of vaccine effectiveness. Conclusions We conclude that although enrolled cases are somewhat more affluent than unenrolled cases, our estimates are externally valid with respect to socioeconomic status. Our analysis provides evidence that this study design can yield valid estimates and the assessing generalisability of observational data is feasible, even when unenrolled individuals cannot be contacted. PMID:28851801

Meta- and statistical analysis of single-case intervention research data: quantitative gifts and a wish list.

PubMed

Kratochwill, Thomas R; Levin, Joel R

2014-04-01

In this commentary, we add to the spirit of the articles appearing in the special series devoted to meta- and statistical analysis of single-case intervention-design data. Following a brief discussion of historical factors leading to our initial involvement in statistical analysis of such data, we discuss: (a) the value added by including statistical-analysis recommendations in the What Works Clearinghouse Standards for single-case intervention designs; (b) the importance of visual analysis in single-case intervention research, along with the distinctive role that could be played by single-case effect-size measures; and (c) the elevated internal validity and statistical-conclusion validity afforded by the incorporation of various forms of randomization into basic single-case design structures. For the future, we envision more widespread application of quantitative analyses, as critical adjuncts to visual analysis, in both primary single-case intervention research studies and literature reviews in the behavioral, educational, and health sciences. Copyright © 2014 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Validation of an improved abnormality insertion method for medical image perception investigations

NASA Astrophysics Data System (ADS)

Madsen, Mark T.; Durst, Gregory R.; Caldwell, Robert T.; Schartz, Kevin M.; Thompson, Brad H.; Berbaum, Kevin S.

2009-02-01

The ability to insert abnormalities in clinical tomographic images makes image perception studies with medical images practical. We describe a new insertion technique and its experimental validation that uses complementary image masks to select an abnormality from a library and place it at a desired location. The method was validated using a 4-alternative forced-choice experiment. For each case, four quadrants were simultaneously displayed consisting of 5 consecutive frames of a chest CT with a pulmonary nodule. One quadrant was unaltered, while the other 3 had the nodule from the unaltered quadrant artificially inserted. 26 different sets were generated and repeated with order scrambling for a total of 52 cases. The cases were viewed by radiology staff and residents who ranked each quadrant by realistic appearance. On average, the observers were able to correctly identify the unaltered quadrant in 42% of cases, and identify the unaltered quadrant both times it appeared in 25% of cases. Consensus, defined by a majority of readers, correctly identified the unaltered quadrant in only 29% of 52 cases. For repeats, the consensus observer successfully identified the unaltered quadrant only once. We conclude that the insertion method can be used to reliably place abnormalities in perception experiments.

Validation of Student and Parent Reported Data on the Basic Grant Application Form, 1978-79 Comprehensive Validation Guide. Procedural Manual for: Validation of Cases Referred by Institutions; Validation of Cases Referred by the Office of Education; Recovery of Overpayments.

ERIC Educational Resources Information Center

Smith, Karen; And Others

Procedures for validating data reported by students and parents on an application for Basic Educational Opportunity Grants were developed in 1978 for the U.S. Office of Education (OE). Validation activities include: validation of flagged Student Eligibility Reports (SERs) for students whose schools are part of the Alternate Disbursement System;…

Do placebo based validation standards mimic real batch products behaviour? Case studies.

PubMed

Bouabidi, A; Talbi, M; Bouklouze, A; El Karbane, M; Bourichi, H; El Guezzar, M; Ziemons, E; Hubert, Ph; Rozet, E

2011-06-01

Analytical methods validation is a mandatory step to evaluate the ability of developed methods to provide accurate results for their routine application. Validation usually involves validation standards or quality control samples that are prepared in placebo or reconstituted matrix made of a mixture of all the ingredients composing the drug product except the active substance or the analyte under investigation. However, one of the main concerns that can be made with this approach is that it may lack an important source of variability that come from the manufacturing process. The question that remains at the end of the validation step is about the transferability of the quantitative performance from validation standards to real authentic drug product samples. In this work, this topic is investigated through three case studies. Three analytical methods were validated using the commonly spiked placebo validation standards at several concentration levels as well as using samples coming from authentic batch samples (tablets and syrups). The results showed that, depending on the type of response function used as calibration curve, there were various degrees of differences in the results accuracy obtained with the two types of samples. Nonetheless the use of spiked placebo validation standards was showed to mimic relatively well the quantitative behaviour of the analytical methods with authentic batch samples. Adding these authentic batch samples into the validation design may help the analyst to select and confirm the most fit for purpose calibration curve and thus increase the accuracy and reliability of the results generated by the method in routine application. Copyright © 2011 Elsevier B.V. All rights reserved.

Computational Acoustic Beamforming for Noise Source Identification for Small Wind Turbines.

PubMed

Ma, Ping; Lien, Fue-Sang; Yee, Eugene

2017-01-01

This paper develops a computational acoustic beamforming (CAB) methodology for identification of sources of small wind turbine noise. This methodology is validated using the case of the NACA 0012 airfoil trailing edge noise. For this validation case, the predicted acoustic maps were in excellent conformance with the results of the measurements obtained from the acoustic beamforming experiment. Following this validation study, the CAB methodology was applied to the identification of noise sources generated by a commercial small wind turbine. The simulated acoustic maps revealed that the blade tower interaction and the wind turbine nacelle were the two primary mechanisms for sound generation for this small wind turbine at frequencies between 100 and 630 Hz.

School-Based Asthma Case Finding: The Arkansas Experience

ERIC Educational Resources Information Center

Vargas, Perla A.; Magee, James S.; Bushmiaer, Margo; Simpson, Pippa M.; Jones, Craig A.; Feild, Charles R.; Jones, Stacie M.

2006-01-01

This population-based case-finding study sought to determine asthma prevalence and characterize disease severity and burden among school-aged children in the Little Rock School District. Asthma cases were identified by validated algorithm and parental report of asthma diagnosis. The overall response rate was low. Among schools with greater than…

Applying Case-Based Method in Designing Self-Directed Online Instruction: A Formative Research Study

ERIC Educational Resources Information Center

Luo, Heng; Koszalka, Tiffany A.; Arnone, Marilyn P.; Choi, Ikseon

2018-01-01

This study investigated the case-based method (CBM) instructional-design theory and its application in designing self-directed online instruction. The purpose of this study was to validate and refine the theory for a self-directed online instruction context. Guided by formative research methodology, this study first developed an online tutorial…

The medline UK filter: development and validation of a geographic search filter to retrieve research about the UK from OVID medline.

PubMed

Ayiku, Lynda; Levay, Paul; Hudson, Tom; Craven, Jenny; Barrett, Elizabeth; Finnegan, Amy; Adams, Rachel

2017-07-13

A validated geographic search filter for the retrieval of research about the United Kingdom (UK) from bibliographic databases had not previously been published. To develop and validate a geographic search filter to retrieve research about the UK from OVID medline with high recall and precision. Three gold standard sets of references were generated using the relative recall method. The sets contained references to studies about the UK which had informed National Institute for Health and Care Excellence (NICE) guidance. The first and second sets were used to develop and refine the medline UK filter. The third set was used to validate the filter. Recall, precision and number-needed-to-read (NNR) were calculated using a case study. The validated medline UK filter demonstrated 87.6% relative recall against the third gold standard set. In the case study, the medline UK filter demonstrated 100% recall, 11.4% precision and a NNR of nine. A validated geographic search filter to retrieve research about the UK with high recall and precision has been developed. The medline UK filter can be applied to systematic literature searches in OVID medline for topics with a UK focus. © 2017 Crown copyright. Health Information and Libraries Journal © 2017 Health Libraries GroupThis article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

Hovering Dual-Spin Vehicle Groundwork for Bias Momentum Sizing Validation Experiment

NASA Technical Reports Server (NTRS)

Rothhaar, Paul M.; Moerder, Daniel D.; Lim, Kyong B.

2008-01-01

Angular bias momentum offers significant stability augmentation for hovering flight vehicles. The reliance of the vehicle on thrust vectoring for agility and disturbance rejection is greatly reduced with significant levels of stored angular momentum in the system. A methodical procedure for bias momentum sizing has been developed in previous studies. This current study provides groundwork for experimental validation of that method using an experimental vehicle called the Dual-Spin Test Device, a thrust-levitated platform. Using measured data the vehicle's thrust vectoring units are modeled and a gust environment is designed and characterized. Control design is discussed. Preliminary experimental results of the vehicle constrained to three rotational degrees of freedom are compared to simulation for a case containing no bias momentum to validate the simulation. A simulation of a bias momentum dominant case is presented.

Approaches to Assessment in CLIL Classrooms: Two Case Studies

ERIC Educational Resources Information Center

O'Dwyer, Fergus; de Boer, Mark

2015-01-01

This article presents two case studies that show how learner involvement and collaboration in assessment are valid pedagogic tools to encourage learner reflection and engagement, particularly where a very traditional approach to language learning is the norm. The authors, who teach in universities in Japan, discuss different but related approaches…

How School Librarians Can Contribute to the Personal Growth of Students with Disabilities.

ERIC Educational Resources Information Center

Murray, Janet

2000-01-01

Discusses building self-esteem and confidence of disabled students through school library programs, based on Australian case studies. Topics include validity and reliability of case studies; the influence of teacher attitudes on student attitudes toward the disabled; physical accessibility; information literacy; information technology use; and…

The Psychometric Properties of Classroom Response System Data: A Case Study

ERIC Educational Resources Information Center

Kortemeyer, Gerd

2016-01-01

Classroom response systems (often referred to as "clickers") have slowly gained adoption over the recent decade; however, critics frequently doubt their pedagogical value starting with the validity of the gathered responses: There is concern that students simply "click" random answers. This case study looks at different…

Impact of random and systematic recall errors and selection bias in case--control studies on mobile phone use and brain tumors in adolescents (CEFALO study).

PubMed

Aydin, Denis; Feychting, Maria; Schüz, Joachim; Andersen, Tina Veje; Poulsen, Aslak Harbo; Prochazka, Michaela; Klaeboe, Lars; Kuehni, Claudia E; Tynes, Tore; Röösli, Martin

2011-07-01

Whether the use of mobile phones is a risk factor for brain tumors in adolescents is currently being studied. Case--control studies investigating this possible relationship are prone to recall error and selection bias. We assessed the potential impact of random and systematic recall error and selection bias on odds ratios (ORs) by performing simulations based on real data from an ongoing case--control study of mobile phones and brain tumor risk in children and adolescents (CEFALO study). Simulations were conducted for two mobile phone exposure categories: regular and heavy use. Our choice of levels of recall error was guided by a validation study that compared objective network operator data with the self-reported amount of mobile phone use in CEFALO. In our validation study, cases overestimated their number of calls by 9% on average and controls by 34%. Cases also overestimated their duration of calls by 52% on average and controls by 163%. The participation rates in CEFALO were 83% for cases and 71% for controls. In a variety of scenarios, the combined impact of recall error and selection bias on the estimated ORs was complex. These simulations are useful for the interpretation of previous case-control studies on brain tumor and mobile phone use in adults as well as for the interpretation of future studies on adolescents. Copyright © 2011 Wiley-Liss, Inc.

Digital pathology for the primary diagnosis of breast histopathological specimens: an innovative validation and concordance study on digital pathology validation and training.

PubMed

Williams, Bethany Jill; Hanby, Andrew; Millican-Slater, Rebecca; Nijhawan, Anju; Verghese, Eldo; Treanor, Darren

2018-03-01

To train and individually validate a group of breast pathologists in specialty-specific digital primary diagnosis by using a novel protocol endorsed by the Royal College of Pathologists' new guideline for digital pathology. The protocol allows early exposure to live digital reporting, in a risk-mitigated environment, and focuses on patient safety and professional development. Three specialty breast pathologists completed training in the use of a digital microscopy system, and were exposed to a training set of 20 challenging cases, designed to help them identify personal digital diagnostic pitfalls. Following this, the three pathologists viewed a total of 694 live, entire breast cases. All primary diagnoses were made on digital slides, with immediate glass slide review and reconciliation before final case sign-out. There was complete clinical concordance between the glass and digital impression of the case in 98.8% of cases. Only 1.2% of cases had a clinically significant difference in diagnosis/prognosis on glass and digital slide reads. All pathologists elected to continue using the digital microscope as the standard for breast histopathology specimens, with deferral to glass for a limited number of clinical/histological scenarios as a safety net. Individual training and validation for digital primary diagnosis allows pathologists to develop competence and confidence in their digital diagnostic skills, and aids safe and responsible transition from the light microscope to the digital microscope. © 2017 John Wiley & Sons Ltd.

[Development and testing of a preparedness and response capacity questionnaire in public health emergency for Chinese provincial and municipal governments].

PubMed

Hu, Guo-Qing; Rao, Ke-Qin; Sun, Zhen-Qiu

2008-12-01

To develop a capacity questionnaire in public health emergency for Chinese local governments. Literature reviews, conceptual modelling, stake-holder analysis, focus group, interview, and Delphi technique were employed together to develop the questionnaire. Classical test theory and case study were used to assess the reliability and validity. (1) A 2-dimension conceptual model was built. A preparedness and response capacity questionnaire in public health emergency with 10 dimensions and 204 items, was developed. (2) Reliability and validity results. Internal consistency: except for dimension 3 and 8, the Cronbach's alpha coefficient of other dimensions was higher than 0.60. The alpha coefficients of dimension 3 and dimension 8 were 0.59 and 0.39 respectively; Content validity: the questionnaire was recognized by the investigatees; Construct validity: the Spearman correlation coefficients among the 10 dimensions fluctuated around 0.50, ranging from 0.26 to 0.75 (P<0.05); Discrimination validity: comparisons of 10 dimensions among 4 provinces did not show statistical significance using One-way analysis of variance (P>0.05). Criterion-related validity: case study showed significant difference among the 10 dimensions in Beijing between February 2003 (before SARS event) and November 2005 (after SARS event). The preparedness and response capacity questionnaire in public health emergency is a reliable and valid tool, which can be used in all provinces and municipalities in China.

I Spy with My Little Eye: Jurors' Detection of Internal Validity Threats in Expert Evidence

PubMed Central

McAuliff, Bradley D.; Duckworth, Tejah D.

2010-01-01

This experiment examined whether jury-eligible community members (N = 223) were able to detect internally invalid psychological science presented at trial. Participants read a simulated child sexual abuse case in which the defense expert described a study he had conducted on witness memory and suggestibility. We varied the study's internal validity (valid, missing control group, confound, and experimenter bias) and publication status (published, unpublished). Expert evidence quality ratings were higher for the valid versus missing control group version only. Publication increased ratings of defendant guilt when the study was missing a control group. Variations in internal validity did not influence perceptions of child victim credibility or police interview quality. Participants' limited detection of internal validity threats underscores the need to examine the effectiveness of traditional legal safeguards against junk science in court and improve the scientific reasoning ability of lay people and legal professionals. PMID:20162342

Real-time Raman spectroscopy for automatic in vivo skin cancer detection: an independent validation.

PubMed

Zhao, Jianhua; Lui, Harvey; Kalia, Sunil; Zeng, Haishan

2015-11-01

In a recent study, we have demonstrated that real-time Raman spectroscopy could be used for skin cancer diagnosis. As a translational study, the objective of this study is to validate previous findings through a completely independent clinical test. In total, 645 confirmed cases were included in the analysis, including a cohort of 518 cases from a previous study, and an independent cohort of 127 new cases. Multi-variant statistical data analyses including principal component with general discriminant analysis (PC-GDA) and partial least squares (PLS) were used separately for lesion classification, which generated similar results. When the previous cohort (n = 518) was used as training and the new cohort (n = 127) was used as testing, the area under the receiver operating characteristic curve (ROC AUC) was found to be 0.889 (95 % CI 0.834-0.944; PLS); when the two cohorts were combined, the ROC AUC was 0.894 (95 % CI 0.870-0.918; PLS) with the narrowest confidence intervals. Both analyses were comparable to the previous findings, where the ROC AUC was 0.896 (95 % CI 0.846-0.946; PLS). The independent study validates that real-time Raman spectroscopy could be used for automatic in vivo skin cancer diagnosis with good accuracy.

A systematic review of validated methods to capture myopericarditis using administrative or claims data.

PubMed

Idowu, Rachel T; Carnahan, Ryan; Sathe, Nila A; McPheeters, Melissa L

2013-12-30

To identify algorithms that can capture incident cases of myocarditis and pericarditis in administrative and claims databases; these algorithms can eventually be used to identify cardiac inflammatory adverse events following vaccine administration. We searched MEDLINE from 1991 to September 2012 using controlled vocabulary and key terms related to myocarditis. We also searched the reference lists of included studies. Two investigators independently assessed the full text of studies against pre-determined inclusion criteria. Two reviewers independently extracted data regarding participant and algorithm characteristics as well as study conduct. Nine publications (including one study reported in two publications) met criteria for inclusion. Two studies performed medical record review in order to confirm that these coding algorithms actually captured patients with the disease of interest. One of these studies identified five potential cases, none of which were confirmed as acute myocarditis upon review. The other study, which employed a search algorithm based on diagnostic surveillance (using ICD-9 codes 420.90, 420.99, 422.90, 422.91 and 429.0) and sentinel reporting, identified 59 clinically confirmed cases of myopericarditis among 492,671 United States military service personnel who received smallpox vaccine between 2002 and 2003. Neither study provided algorithm validation statistics (positive predictive value, sensitivity, or specificity). A validated search algorithm is currently unavailable for identifying incident cases of pericarditis or myocarditis. Several authors have published unvalidated ICD-9-based search algorithms that appear to capture myocarditis events occurring in the context of other underlying cardiac or autoimmune conditions. Copyright © 2013. Published by Elsevier Ltd.

Establishing the Validity of Recovery from Stuttering without Formal Treatment.

ERIC Educational Resources Information Center

Finn, Patrick

1996-01-01

This study examined a validation procedure combining self-reports with independent verification to identify cases of recovery from stuttering without formal treatment. A Speech Behavior Checklist was administered to 42 individuals familiar with recovered subjects' past speech. Analysis of subjects' descriptions of their past stuttering was…

Flexible Programmes in Higher Professional Education: Expert Validation of a Flexible Educational Model

ERIC Educational Resources Information Center

Schellekens, Ad; Paas, Fred; Verbraeck, Alexander; van Merrienboer, Jeroen J. G.

2010-01-01

In a preceding case study, a process-focused demand-driven approach for organising flexible educational programmes in higher professional education (HPE) was developed. Operations management and instructional design contributed to designing a flexible educational model by means of discrete-event simulation. Educational experts validated the model…

An empirical assessment of validation practices for molecular classifiers

PubMed Central

Castaldi, Peter J.; Dahabreh, Issa J.

2011-01-01

Proposed molecular classifiers may be overfit to idiosyncrasies of noisy genomic and proteomic data. Cross-validation methods are often used to obtain estimates of classification accuracy, but both simulations and case studies suggest that, when inappropriate methods are used, bias may ensue. Bias can be bypassed and generalizability can be tested by external (independent) validation. We evaluated 35 studies that have reported on external validation of a molecular classifier. We extracted information on study design and methodological features, and compared the performance of molecular classifiers in internal cross-validation versus external validation for 28 studies where both had been performed. We demonstrate that the majority of studies pursued cross-validation practices that are likely to overestimate classifier performance. Most studies were markedly underpowered to detect a 20% decrease in sensitivity or specificity between internal cross-validation and external validation [median power was 36% (IQR, 21–61%) and 29% (IQR, 15–65%), respectively]. The median reported classification performance for sensitivity and specificity was 94% and 98%, respectively, in cross-validation and 88% and 81% for independent validation. The relative diagnostic odds ratio was 3.26 (95% CI 2.04–5.21) for cross-validation versus independent validation. Finally, we reviewed all studies (n = 758) which cited those in our study sample, and identified only one instance of additional subsequent independent validation of these classifiers. In conclusion, these results document that many cross-validation practices employed in the literature are potentially biased and genuine progress in this field will require adoption of routine external validation of molecular classifiers, preferably in much larger studies than in current practice. PMID:21300697

Validation of Student and Parent Reported Data on the Basic Grant Application Form: Institution/OE Referral Study, Pre-Established and ACT Criteria Study, Overpayment Recovery. Final Report, Volume 2.

ERIC Educational Resources Information Center

Walters, Pamela Barnhouse; And Others

The validity of information provided in applications to the Basic Educational Opportunity Grant (BEOG) program was studied, along with procedures used in recovering overpayments. The objective was to investigate misreporting and misuse of the BEOG program. A 1977-1978 study reviewed cases referred to the U.S. Office of Education by educational…

The Validity of the Comparative Interrupted Time Series Design for Evaluating the Effect of School-Level Interventions.

PubMed

Jacob, Robin; Somers, Marie-Andree; Zhu, Pei; Bloom, Howard

2016-06-01

In this article, we examine whether a well-executed comparative interrupted time series (CITS) design can produce valid inferences about the effectiveness of a school-level intervention. This article also explores the trade-off between bias reduction and precision loss across different methods of selecting comparison groups for the CITS design and assesses whether choosing matched comparison schools based only on preintervention test scores is sufficient to produce internally valid impact estimates. We conduct a validation study of the CITS design based on the federal Reading First program as implemented in one state using results from a regression discontinuity design as a causal benchmark. Our results contribute to the growing base of evidence regarding the validity of nonexperimental designs. We demonstrate that the CITS design can, in our example, produce internally valid estimates of program impacts when multiple years of preintervention outcome data (test scores in the present case) are available and when a set of reasonable criteria are used to select comparison organizations (schools in the present case). © The Author(s) 2016.

Further Validation of a CFD Code for Calculating the Performance of Two-Stage Light Gas Guns

NASA Technical Reports Server (NTRS)

Bogdanoff, David W.

2017-01-01

Earlier validations of a higher-order Godunov code for modeling the performance of two-stage light gas guns are reviewed. These validation comparisons were made between code predictions and experimental data from the NASA Ames 1.5" and 0.28" guns and covered muzzle velocities of 6.5 to 7.2 km/s. In the present report, five more series of code validation comparisons involving experimental data from the Ames 0.22" (1.28" pump tube diameter), 0.28", 0.50", 1.00" and 1.50" guns are presented. The total muzzle velocity range of the validation data presented herein is 3 to 11.3 km/s. The agreement between the experimental data and CFD results is judged to be very good. Muzzle velocities were predicted within 0.35 km/s for 74% of the cases studied with maximum differences being 0.5 km/s and for 4 out of 50 cases, 0.5 - 0.7 km/s.

Design Characteristics Influence Performance of Clinical Prediction Rules in Validation: A Meta-Epidemiological Study

PubMed Central

Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda

2016-01-01

Background Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules’ performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Methods Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. Results A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2–4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Conclusion Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved. PMID:26730980

Design Characteristics Influence Performance of Clinical Prediction Rules in Validation: A Meta-Epidemiological Study.

PubMed

Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda

2016-01-01

Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules' performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2-4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved.

Helping Crisis Managers Protect Reputational Assets: Initial Tests of the Situational Crisis Communication Theory.

ERIC Educational Resources Information Center

Coombs, W. Timothy; Holladay, Sherry J.

2002-01-01

Explains a comprehensive, prescriptive, situational approach for responding to crises and protecting organizational reputation: the situational crisis communication theory (SCCT). Notes undergraduate students read two crisis case studies from a set of 13 cases and responded to questions following the case. Validates a key assumption in SCCT and…

The statistical validity of nursing home survey findings.

PubMed

Woolley, Douglas C

2011-11-01

The Medicare nursing home survey is a high-stakes process whose findings greatly affect nursing homes, their current and potential residents, and the communities they serve. Therefore, survey findings must achieve high validity. This study looked at the validity of one key assessment made during a nursing home survey: the observation of the rate of errors in administration of medications to residents (med-pass). Statistical analysis of the case under study and of alternative hypothetical cases. A skilled nursing home affiliated with a local medical school. The nursing home administrators and the medical director. Observational study. The probability that state nursing home surveyors make a Type I or Type II error in observing med-pass error rates, based on the current case and on a series of postulated med-pass error rates. In the common situation such as our case, where med-pass errors occur at slightly above a 5% rate after 50 observations, and therefore trigger a citation, the chance that the true rate remains above 5% after a large number of observations is just above 50%. If the true med-pass error rate were as high as 10%, and the survey team wished to achieve 75% accuracy in determining that a citation was appropriate, they would have to make more than 200 med-pass observations. In the more common situation where med pass errors are closer to 5%, the team would have to observe more than 2000 med-passes to achieve even a modest 75% accuracy in their determinations. In settings where error rates are low, large numbers of observations of an activity must be made to reach acceptable validity of estimates for the true rates of errors. In observing key nursing home functions with current methodology, the State Medicare nursing home survey process does not adhere to well-known principles of valid error determination. Alternate approaches in survey methodology are discussed. Copyright © 2011 American Medical Directors Association. Published by Elsevier Inc. All rights reserved.

Issues and challenges of involving users in medical device development.

PubMed

Bridgelal Ram, Mala; Grocott, Patricia R; Weir, Heather C M

2008-03-01

User engagement has become a central tenet of health-care policy. This paper reports on a case study in progress that highlights user engagement in the research process in relation to medical device development. To work with a specific group of medical device users to uncover unmet needs, translating these into design concepts, novel technologies and products. To validate a knowledge transfer model that may be replicated for a range of medical device applications and user groups. In depth qualitative case study to elicit and analyse user needs. The focus is on identifying design concepts for medical device applications from unmet needs, and validating these in an iterative feedback loop to the users. The case study has highlighted three interrelated challenges: ensuring unmet needs drive new design concepts and technology development; managing user expectations and managing the research process. Despite the challenges, active participation of users is crucial to developing usable and clinically effective devices.

Teaching neurophysiology, neuropharmacology, and experimental design using animal models of psychiatric and neurological disorders.

PubMed

Morsink, Maarten C; Dukers, Danny F

2009-03-01

Animal models have been widely used for studying the physiology and pharmacology of psychiatric and neurological diseases. The concepts of face, construct, and predictive validity are used as indicators to estimate the extent to which the animal model mimics the disease. Currently, we used these three concepts to design a theoretical assignment to integrate the teaching of neurophysiology, neuropharmacology, and experimental design. For this purpose, seven case studies were developed in which animal models for several psychiatric and neurological diseases were described and in which neuroactive drugs used to treat or study these diseases were introduced. Groups of undergraduate students were assigned to one of these case studies and asked to give a classroom presentation in which 1) the disease and underlying pathophysiology are described, 2) face and construct validity of the animal model are discussed, and 3) a pharmacological experiment with the associated neuroactive drug to assess predictive validity is presented. After evaluation of the presentations, we found that the students had gained considerable insight into disease phenomenology, its underlying neurophysiology, and the mechanism of action of the neuroactive drug. Moreover, the assignment was very useful in the teaching of experimental design, allowing an in-depth discussion of experimental control groups and the prediction of outcomes in these groups if the animal model were to display predictive validity. Finally, the highly positive responses in the student evaluation forms indicated that the assignment was of great interest to the students. Hence, the currently developed case studies constitute a very useful tool for teaching neurophysiology, neuropharmacology, and experimental design.

The 2014 Sandia Verification and Validation Challenge: Problem statement

DOE PAGES

Hu, Kenneth; Orient, George

2016-01-18

This paper presents a case study in utilizing information from experiments, models, and verification and validation (V&V) to support a decision. It consists of a simple system with data and models provided, plus a safety requirement to assess. The goal is to pose a problem that is flexible enough to allow challengers to demonstrate a variety of approaches, but constrained enough to focus attention on a theme. This was accomplished by providing a good deal of background information in addition to the data, models, and code, but directing the participants' activities with specific deliverables. In this challenge, the theme ismore » how to gather and present evidence about the quality of model predictions, in order to support a decision. This case study formed the basis of the 2014 Sandia V&V Challenge Workshop and this resulting special edition of the ASME Journal of Verification, Validation, and Uncertainty Quantification.« less

Computational Acoustic Beamforming for Noise Source Identification for Small Wind Turbines

PubMed Central

Lien, Fue-Sang

2017-01-01

This paper develops a computational acoustic beamforming (CAB) methodology for identification of sources of small wind turbine noise. This methodology is validated using the case of the NACA 0012 airfoil trailing edge noise. For this validation case, the predicted acoustic maps were in excellent conformance with the results of the measurements obtained from the acoustic beamforming experiment. Following this validation study, the CAB methodology was applied to the identification of noise sources generated by a commercial small wind turbine. The simulated acoustic maps revealed that the blade tower interaction and the wind turbine nacelle were the two primary mechanisms for sound generation for this small wind turbine at frequencies between 100 and 630 Hz. PMID:28378012

[Validation of SHI Claims Data Exemplified by Gender-specific Diagnoses].

PubMed

Hartmann, J; Weidmann, C; Biehle, R

2016-10-01

Aim: Use of statutory health insurance (SHI) data in health services research is increasing steadily and questions of validity are gaining importance. Using gender-specific diagnosis as an example, the aim of this study was to estimate the prevalence of implausible diagnosis and demonstrate an internal validation strategy. Method: The analysis is based on the SHI data from Baden-Württemberg for 2012. Subject of validation are gender-specific outpatient diagnoses that mismatch with the gender of the insured. To uncover this implausibility, it is necessary to clarify whether the diagnosis or the gender is wrong. The validation criteria used were the presence of further gender-specific diagnoses, the presence of gender-specific settlement items, the specialization of the physician in charge and the gender assignment of the first name of the insured. To review the quality of the validation, it was verified if the gender was changed during the following year. Results: Around 5.1% of all diagnoses were gender-specific and there was a mismatch between diagnosis and gender in 0.04% of these cases. All validation criteria were useful to sort out implausibility, whereas the last one was the most effective. Only 14% remained unsolved. From the total of 1 145 insured with implausible gender-specific diagnoses, one year later 128 had a new gender (in the data). 119 of these cases were rightly classified as insured with wrong gender and 9 cases were in the unsolved group. This confirms that the validation works well. Conclusion: Implausibility in SHI data is relatively small and can be solved with appropriate validation criteria. When validating SHI data, it is advisable to question all data used critically, to use multiple validation criteria instead of just one and to abandon the idea that reality and the associated data conform to standardized norms. Keeping these aspects in mind, analysis of SHI data is a good starting point for research in health services. © Georg Thieme Verlag KG Stuttgart · New York.

A Synthesis Model of Sustainable Market Orientation: Conceptualization, Measurement, and Influence on Academic Accreditation--A Case Study of Egyptian-Accredited Faculties

ERIC Educational Resources Information Center

Abou-Warda, Sherein H.

2014-01-01

Higher education institutions are increasingly concerned about accreditation. Although sustainable market orientation (SMO) bears on academic accreditation, to date, no study has developed a valid scale of SMO or assessed its influence on accreditation. The purpose of this paper is to construct and validate an SMO scale that was developed in…

DNA Commission of the International Society for Forensic Genetics: Recommendations on the validation of software programs performing biostatistical calculations for forensic genetics applications.

PubMed

Coble, M D; Buckleton, J; Butler, J M; Egeland, T; Fimmers, R; Gill, P; Gusmão, L; Guttman, B; Krawczak, M; Morling, N; Parson, W; Pinto, N; Schneider, P M; Sherry, S T; Willuweit, S; Prinz, M

2016-11-01

The use of biostatistical software programs to assist in data interpretation and calculate likelihood ratios is essential to forensic geneticists and part of the daily case work flow for both kinship and DNA identification laboratories. Previous recommendations issued by the DNA Commission of the International Society for Forensic Genetics (ISFG) covered the application of bio-statistical evaluations for STR typing results in identification and kinship cases, and this is now being expanded to provide best practices regarding validation and verification of the software required for these calculations. With larger multiplexes, more complex mixtures, and increasing requests for extended family testing, laboratories are relying more than ever on specific software solutions and sufficient validation, training and extensive documentation are of upmost importance. Here, we present recommendations for the minimum requirements to validate bio-statistical software to be used in forensic genetics. We distinguish between developmental validation and the responsibilities of the software developer or provider, and the internal validation studies to be performed by the end user. Recommendations for the software provider address, for example, the documentation of the underlying models used by the software, validation data expectations, version control, implementation and training support, as well as continuity and user notifications. For the internal validations the recommendations include: creating a validation plan, requirements for the range of samples to be tested, Standard Operating Procedure development, and internal laboratory training and education. To ensure that all laboratories have access to a wide range of samples for validation and training purposes the ISFG DNA commission encourages collaborative studies and public repositories of STR typing results. Published by Elsevier Ireland Ltd.

Evaluation of a surveillance case definition for anogenital warts, Kaiser Permanente northwest.

PubMed

Naleway, Allison L; Weinmann, Sheila; Crane, Brad; Gee, Julianne; Markowitz, Lauri E; Dunne, Eileen F

2014-08-01

Most studies of anogenital wart (AGW) epidemiology have used large clinical or administrative databases and unconfirmed case definitions based on combinations of diagnosis and procedure codes. We developed and validated an AGW case definition using a combination of diagnosis codes and other information available in the electronic medical record (provider type, laboratory testing). We calculated the positive predictive value (PPV) of this case definition compared with manual medical record review in a random sample of 250 cases. Using this case definition, we calculated the annual age- and sex-stratified prevalence of AGW among individuals 11 through 30 years of age from 2000 through 2005. We identified 2730 individuals who met the case definition. The PPV of the case definition was 82%, and the average annual prevalence was 4.16 per 1000. Prevalence of AGW was higher in females compared with males in every age group, with the exception of the 27- to 30-year-olds. Among females, prevalence peaked in the 19- to 22-year-olds, and among males, the peak was observed in 23- to 26-year-olds. The case definition developed in this study is the first to be validated with medical record review and has a good PPV for the detection of AGW. The prevalence rates observed in this study were higher than other published rates, but the age- and sex-specific patterns observed were consistent with previous reports.

Detecting depression among adolescents in Santiago, Chile: sex differences.

PubMed

Araya, Ricardo; Montero-Marin, Jesus; Barroilhet, Sergio; Fritsch, Rosemarie; Gaete, Jorge; Montgomery, Alan

2013-04-23

Depression among adolescents is common but most cases go undetected. Brief questionnaires offer an opportunity to identify probable cases but properly validated cut-off points are often unavailable, especially in non-western countries. Sex differences in the prevalence of depression become marked in adolescence and this needs to be accounted when establishing cut-off points. This study involved adolescents attending secondary state schools in Santiago, Chile. We compared the self-reported Beck Depression Inventory-II with a psychiatric interview to ascertain diagnosis. General psychometric features were estimated before establishing the criterion validity of the BDI-II. The BDI-II showed good psychometric properties with good internal consistency, a clear unidimensional factorial structure, and good capacity to discriminate between cases and non-cases of depression. Optimal cut-off points to establish caseness for depression were much higher for girls than boys. Sex discrepancies were primarily explained by differences in scores among those with depression rather than among those without depression. It is essential to validate scales with the populations intended to be used with. Sex differences are often ignored when applying cut-off points, leading to substantial misclassification. Early detection of depression is essential if we think that early intervention is a clinically important goal.

FAST Model Calibration and Validation of the OC5-DeepCwind Floating Offshore Wind System Against Wave Tank Test Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wendt, Fabian F; Robertson, Amy N; Jonkman, Jason

During the course of the Offshore Code Comparison Collaboration, Continued, with Correlation (OC5) project, which focused on the validation of numerical methods through comparison against tank test data, the authors created a numerical FAST model of the 1:50-scale DeepCwind semisubmersible system that was tested at the Maritime Research Institute Netherlands ocean basin in 2013. This paper discusses several model calibration studies that were conducted to identify model adjustments that improve the agreement between the numerical simulations and the experimental test data. These calibration studies cover wind-field-specific parameters (coherence, turbulence), hydrodynamic and aerodynamic modeling approaches, as well as rotor model (blade-pitchmore » and blade-mass imbalances) and tower model (structural tower damping coefficient) adjustments. These calibration studies were conducted based on relatively simple calibration load cases (wave only/wind only). The agreement between the final FAST model and experimental measurements is then assessed based on more-complex combined wind and wave validation cases.« less

Development and Validation of the Minnesota Borderline Personality Disorder Scale

ERIC Educational Resources Information Center

Bornovalova, Marina A.; Hicks, Brian M.; Patrick, Christopher J.; Iacono, William G.; McGue, Matt

2011-01-01

Although large epidemiological data sets can inform research on the etiology and development of borderline personality disorder (BPD), they rarely include BPD measures. In some cases, however, proxy measures can be constructed using instruments already in these data sets. In this study, the authors developed and validated a self-report measure of…

Co-Occurrence of ADHD and High IQ: A Case Series Empirical Study

ERIC Educational Resources Information Center

Cordeiro, Mara L.; Farias, Antonio C.; Cunha, Alexandre; Benko, Cassia R.; Farias, Lucilene G.; Costa, Maria T.; Martins, Leandra F.; McCracken, James T.

2011-01-01

Objective: The validity of a diagnosis of ADHD in children with a high intelligence quotient (IQ) remains controversial. Using a multidisciplinary approach, rigorous diagnostic criteria, and worldwide-validated psychometric instruments, we identified a group of children attending public schools in southern Brazil for co-occurrence of high IQ and…

Validation of in situ networks via field sampling: case study in the South Fork Experimental Watershed

USDA-ARS?s Scientific Manuscript database

The calibration and validation of soil moisture remote sensing products is complicated by the logistics of installing a soil moisture network for a long term period in an active landscape. Therefore, these stations are located along field boundaries or in non-representative sites with regards to so...

Framework to parameterize and validate APEX to support deployment of the nutrient tracking tool

USDA-ARS?s Scientific Manuscript database

Guidelines have been developed to parameterize and validate the Agricultural Policy Environmental eXtender (APEX) to support the Nutrient Tracking Tool (NTT). This follow-up paper presents 1) a case study to illustrate how the developed guidelines are applied in a headwater watershed located in cent...

Developing a Time Series Predictive Model for Dengue in Zhongshan, China Based on Weather and Guangzhou Dengue Surveillance Data.

PubMed

Zhang, Yingtao; Wang, Tao; Liu, Kangkang; Xia, Yao; Lu, Yi; Jing, Qinlong; Yang, Zhicong; Hu, Wenbiao; Lu, Jiahai

2016-02-01

Dengue is a re-emerging infectious disease of humans, rapidly growing from endemic areas to dengue-free regions due to favorable conditions. In recent decades, Guangzhou has again suffered from several big outbreaks of dengue; as have its neighboring cities. This study aims to examine the impact of dengue epidemics in Guangzhou, China, and to develop a predictive model for Zhongshan based on local weather conditions and Guangzhou dengue surveillance information. We obtained weekly dengue case data from 1st January, 2005 to 31st December, 2014 for Guangzhou and Zhongshan city from the Chinese National Disease Surveillance Reporting System. Meteorological data was collected from the Zhongshan Weather Bureau and demographic data was collected from the Zhongshan Statistical Bureau. A negative binomial regression model with a log link function was used to analyze the relationship between weekly dengue cases in Guangzhou and Zhongshan, controlling for meteorological factors. Cross-correlation functions were applied to identify the time lags of the effect of each weather factor on weekly dengue cases. Models were validated using receiver operating characteristic (ROC) curves and k-fold cross-validation. Our results showed that weekly dengue cases in Zhongshan were significantly associated with dengue cases in Guangzhou after the treatment of a 5 weeks prior moving average (Relative Risk (RR) = 2.016, 95% Confidence Interval (CI): 1.845-2.203), controlling for weather factors including minimum temperature, relative humidity, and rainfall. ROC curve analysis indicated our forecasting model performed well at different prediction thresholds, with 0.969 area under the receiver operating characteristic curve (AUC) for a threshold of 3 cases per week, 0.957 AUC for a threshold of 2 cases per week, and 0.938 AUC for a threshold of 1 case per week. Models established during k-fold cross-validation also had considerable AUC (average 0.938-0.967). The sensitivity and specificity obtained from k-fold cross-validation was 78.83% and 92.48% respectively, with a forecasting threshold of 3 cases per week; 91.17% and 91.39%, with a threshold of 2 cases; and 85.16% and 87.25% with a threshold of 1 case. The out-of-sample prediction for the epidemics in 2014 also showed satisfactory performance. Our study findings suggest that the occurrence of dengue outbreaks in Guangzhou could impact dengue outbreaks in Zhongshan under suitable weather conditions. Future studies should focus on developing integrated early warning systems for dengue transmission including local weather and human movement.

Validation of Serum Markers for the Early Detection of Hepatocellular Carcinoma — EDRN Public Portal

Cancer.gov

Using the guidelines for cancer biomarker validation suggested by Pepe et al. (23), we propose to perform a Phase 2 study of DCP for the detection of early stage HCC. In this proposal, we plan to perform a larger case-control study to compare the sensitivity and specificity of DCP and AFP alone and in combination in differentiating patients with all stages of HCC and more importantly those with early HCC from patients with cirrhosis. We plan to enroll consecutive patients with HCC seen at 7 centers in the United States. Controls are frequency matched to cases (all center combined) using the following criteria: age (±10 years), gender (+10%) and etiology of liver disease (viral vs non-viral (+5%). Within each participating institution, there will be an equal number (+20%) of cases and controls.

A Mixed-Method Analysis of Reports on 100 Cases of Improper Prescribing of Controlled Substances

PubMed Central

DuBois, James M.; Chibnall, John T.; Anderson, Emily E.; Eggers, Michelle; Baldwin, Kari; Vasher, Meghan

2017-01-01

Improper prescribing of controlled substances contributes to opioid addictions and deaths by overdose. Studies conducted to-date have largely lacked a theoretical framework and ignored the interaction of individual with environmental factors. We conducted a mixed-method analysis of published reports on 100 cases that occurred in the United States. An average of 17 reports (e.g., from medical boards) per case were coded for 38 dichotomous variables describing the physician, setting, patients, and investigation. A theory on how the case occurred was developed for each case. Explanatory typologies were developed and then validated through hierarchical cluster analysis. Most cases involved physicians who were male (88%), >40 years old (90%), non-board certified (63%), and in small private practices (97%); 54% of cases reported facts about the physician indicative of self-centered personality traits. Three explanatory typologies were validated. Increasing oversight provided by peers and trainees may help prevent improper prescribing of controlled substances. PMID:28663601

The validity of proxy-based data on loneliness in suicide research: a case-control psychological autopsy study in rural China.

PubMed

Niu, Lu; Jia, Cunxian; Ma, Zhenyu; Wang, Guojun; Yu, Zhenjun; Zhou, Liang

2018-05-01

There is a lack of evidence for the role of loneliness on suicide using psychological autopsy method, and the validity of proxy informants' reports on loneliness is not well established. This study aimed to investigate the validity of proxy respondent reports on loneliness, and the reliability and validity of the University of California Los Angeles Loneliness Scale-6 (ULS-6) as used in psychological autopsy method with rural elderly people in China. Two hundred forty-two suicide cases and 242 normal community controls were selected, and the psychological autopsy method was utilized to collect information. Data from proxy respondents of the living controls were compared with data reported by the targets (gold standards). Subject-proxy concordance for ULS-6 was fair (ICC = 0.447) in the living controls. The suicide cases were more likely to have a higher score of ULS-6 than the living controls. Additionally, our data supported that ULS-6 had adequate psychometric properties in both suicide and control groups: factor analyses yielded one-factor component solution; Cronbach's alpha (both > 0.90) demonstrated excellent internal consistency; the Spearman correlation analysis indicated that the ULS-6 score was positively correlated with depression; and negatively correlated with QOL and social support. Results support proxy-based data on loneliness in research of suicide in older adults in rural China, and the ULS-6 is a psychometrically sound instrument for measuring loneliness in psychological autopsy studies.

Primary central nervous system lymphoma and glioblastoma differentiation based on conventional magnetic resonance imaging by high-throughput SIFT features.

PubMed

Chen, Yinsheng; Li, Zeju; Wu, Guoqing; Yu, Jinhua; Wang, Yuanyuan; Lv, Xiaofei; Ju, Xue; Chen, Zhongping

2018-07-01

Due to the totally different therapeutic regimens needed for primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM), accurate differentiation of the two diseases by noninvasive imaging techniques is important for clinical decision-making. Thirty cases of PCNSL and 66 cases of GBM with conventional T1-contrast magnetic resonance imaging (MRI) were analyzed in this study. Convolutional neural networks was used to segment tumor automatically. A modified scale invariant feature transform (SIFT) method was utilized to extract three-dimensional local voxel arrangement information from segmented tumors. Fisher vector was proposed to normalize the dimension of SIFT features. An improved genetic algorithm (GA) was used to extract SIFT features with PCNSL and GBM discrimination ability. The data-set was divided into a cross-validation cohort and an independent validation cohort by the ratio of 2:1. Support vector machine with the leave-one-out cross-validation based on 20 cases of PCNSL and 44 cases of GBM was employed to build and validate the differentiation model. Among 16,384 high-throughput features, 1356 features show significant differences between PCNSL and GBM with p < 0.05 and 420 features with p < 0.001. A total of 496 features were finally chosen by improved GA algorithm. The proposed method produces PCNSL vs. GBM differentiation with an area under the curve (AUC) curve of 99.1% (98.2%), accuracy 95.3% (90.6%), sensitivity 85.0% (80.0%) and specificity 100% (95.5%) on the cross-validation cohort (and independent validation cohort). Since the local voxel arrangement characterization provided by SIFT features, proposed method produced more competitive PCNSL and GBM differentiation performance by using conventional MRI than methods based on advanced MRI.

Implementation of Network Leader Sponsored Supply Chain Management Systems: A Case Study of Supplier IT Business Value

ERIC Educational Resources Information Center

Miller, Mark S.

2010-01-01

This qualitative multiple-case study was conducted to explore and understand how the implementation of required relationship-specific supply chain management system (SCMS) dictated by the network leader within a supplier network affects a supplier organization. The study, on a very broad sense, attempted to research the current validity of how the…

Does a Claims Diagnosis of Autism Mean a True Case?

ERIC Educational Resources Information Center

Burke, James P.; Jain, Anjali; Yang, Wenya; Kelly, Jonathan P.; Kaiser, Marygrace; Becker, Laura; Lawer, Lindsay; Newschaffer, Craig J.

2014-01-01

The purpose of this study was to validate autism spectrum disorder cases identified through claims-based case identification algorithms against a clinical review of medical charts. Charts were reviewed for 432 children who fell into one of the three following groups: (a) more than or equal to two claims with an autism spectrum disorder diagnosis…

Development and validation of surgical training tool: cystectomy assessment and surgical evaluation (CASE) for robot-assisted radical cystectomy for men.

PubMed

Hussein, Ahmed A; Sexton, Kevin J; May, Paul R; Meng, Maxwell V; Hosseini, Abolfazl; Eun, Daniel D; Daneshmand, Siamak; Bochner, Bernard H; Peabody, James O; Abaza, Ronney; Skinner, Eila C; Hautmann, Richard E; Guru, Khurshid A

2018-04-13

We aimed to develop a structured scoring tool: cystectomy assessment and surgical evaluation (CASE) that objectively measures and quantifies performance during robot-assisted radical cystectomy (RARC) for men. A multinational 10-surgeon expert panel collaborated towards development and validation of CASE. The critical steps of RARC in men were deconstructed into nine key domains, each assessed by five anchors. Content validation was done utilizing the Delphi methodology. Each anchor was assessed in terms of context, score concordance, and clarity. The content validity index (CVI) was calculated for each aspect. A CVI ≥ 0.75 represented consensus, and this statement was removed from the next round. This process was repeated until consensus was achieved for all statements. CASE was used to assess de-identified videos of RARC to determine reliability and construct validity. Linearly weighted percent agreement was used to assess inter-rater reliability (IRR). A logit model for odds ratio (OR) was used to assess construct validation. The expert panel reached consensus on CASE after four rounds. The final eight domains of the CASE included: pelvic lymph node dissection, development of the peri-ureteral space, lateral pelvic space, anterior rectal space, control of the vascular pedicle, anterior vesical space, control of the dorsal venous complex, and apical dissection. IRR > 0.6 was achieved for all eight domains. Experts outperformed trainees across all domains. We developed and validated a reliable structured, procedure-specific tool for objective evaluation of surgical performance during RARC. CASE may help differentiate novice from expert performances.

From patient care to research: a validation study examining the factors contributing to data quality in a primary care electronic medical record database.

PubMed

Coleman, Nathan; Halas, Gayle; Peeler, William; Casaclang, Natalie; Williamson, Tyler; Katz, Alan

2015-02-05

Electronic Medical Records (EMRs) are increasingly used in the provision of primary care and have been compiled into databases which can be utilized for surveillance, research and informing practice. The primary purpose of these records is for the provision of individual patient care; validation and examination of underlying limitations is crucial for use for research and data quality improvement. This study examines and describes the validity of chronic disease case definition algorithms and factors affecting data quality in a primary care EMR database. A retrospective chart audit of an age stratified random sample was used to validate and examine diagnostic algorithms applied to EMR data from the Manitoba Primary Care Research Network (MaPCReN), part of the Canadian Primary Care Sentinel Surveillance Network (CPCSSN). The presence of diabetes, hypertension, depression, osteoarthritis and chronic obstructive pulmonary disease (COPD) was determined by review of the medical record and compared to algorithm identified cases to identify discrepancies and describe the underlying contributing factors. The algorithm for diabetes had high sensitivity, specificity and positive predictive value (PPV) with all scores being over 90%. Specificities of the algorithms were greater than 90% for all conditions except for hypertension at 79.2%. The largest deficits in algorithm performance included poor PPV for COPD at 36.7% and limited sensitivity for COPD, depression and osteoarthritis at 72.0%, 73.3% and 63.2% respectively. Main sources of discrepancy included missing coding, alternative coding, inappropriate diagnosis detection based on medications used for alternate indications, inappropriate exclusion due to comorbidity and loss of data. Comparison to medical chart review shows that at MaPCReN the CPCSSN case finding algorithms are valid with a few limitations. This study provides the basis for the validated data to be utilized for research and informs users of its limitations. Analysis of underlying discrepancies provides the ability to improve algorithm performance and facilitate improved data quality.

Validation of a research case definition of Gulf War illness in the 1991 US military population.

PubMed

Iannacchione, Vincent G; Dever, Jill A; Bann, Carla M; Considine, Kathleen A; Creel, Darryl; Carson, Christopher P; Best, Heather; Haley, Robert W

2011-01-01

A case definition of Gulf War illness with 3 primary variants, previously developed by factor analysis of symptoms in a US Navy construction battalion and validated in clinic veterans, identified ill veterans with objective abnormalities of brain function. This study tests prestated hypotheses of its external validity. A stratified probability sample (n = 8,020), selected from a sampling frame of the 3.5 million Gulf War era US military veterans, completed a computer-assisted telephone interview survey. Application of the prior factor weights to the subjects' responses generated the case definition. The structural equation model of the case definition fit both random halves of the population sample well (root mean-square error of approximation = 0.015). The overall case definition was 3.87 times (95% confidence interval, 2.61-5.74) more prevalent in the deployed than the deployable nondeployed veterans: 3.33 (1.10-10.10) for syndrome variant 1; 5.11 (2.43-10.75) for variant 2, and 4.25 (2.33-7.74) for variant 3. Functional status on SF-12 was greatly reduced (effect sizes, 1.0-2.0) in veterans meeting the overall and variant case definitions. The factor case definition applies to the full Gulf War veteran population and has good characteristics for research. Copyright © 2011 S. Karger AG, Basel.

Validating agent oriented methodology (AOM) for netlogo modelling and simulation

NASA Astrophysics Data System (ADS)

WaiShiang, Cheah; Nissom, Shane; YeeWai, Sim; Sharbini, Hamizan

2017-10-01

AOM (Agent Oriented Modeling) is a comprehensive and unified agent methodology for agent oriented software development. AOM methodology was proposed to aid developers with the introduction of technique, terminology, notation and guideline during agent systems development. Although AOM methodology is claimed to be capable of developing a complex real world system, its potential is yet to be realized and recognized by the mainstream software community and the adoption of AOM is still at its infancy. Among the reason is that there are not much case studies or success story of AOM. This paper presents two case studies on the adoption of AOM for individual based modelling and simulation. It demonstrate how the AOM is useful for epidemiology study and ecological study. Hence, it further validate the AOM in a qualitative manner.

Development and validation of a protocol for optimizing the use of paraffin blocks in molecular epidemiological studies: The example from the HPV-AHEAD study.

PubMed

Mena, Marisa; Lloveras, Belen; Tous, Sara; Bogers, Johannes; Maffini, Fausto; Gangane, Nitin; Kumar, Rekha Vijay; Somanathan, Thara; Lucas, Eric; Anantharaman, Devasena; Gheit, Tarik; Castellsagué, Xavier; Pawlita, Michael; de Sanjosé, Silvia; Alemany, Laia; Tommasino, Massimo

2017-01-01

Worldwide use of formalin-fixed paraffin-embedded blocks (FFPE) is extensive in diagnosis and research. Yet, there is a lack of optimized/standardized protocols to process the blocks and verify the quality and presence of the targeted tissue. In the context of an international study on head and neck cancer (HNC)-HPV-AHEAD, a standardized protocol for optimizing the use of FFPEs in molecular epidemiology was developed and validated. First, a protocol for sectioning the FFPE was developed to prevent cross-contamination and distributed between participating centers. Before processing blocks, all sectioning centers underwent a quality control to guarantee a satisfactory training process. The first and last sections of the FFPEs were used for histopathological assessment. A consensus histopathology evaluation form was developed by an international panel of pathologists and evaluated for four indicators in a pilot analysis in order to validate it: 1) presence/type of tumor tissue, 2) identification of other tissue components that could affect the molecular diagnosis and 3) quality of the tissue. No HPV DNA was found in sections from empty FFPE generated in any histology laboratories of HPV-AHEAD consortium and all centers passed quality assurance for processing after quality control. The pilot analysis to validate the histopathology form included 355 HNC cases. The form was filled by six pathologists and each case was randomly assigned to two of them. Most samples (86%) were considered satisfactory. Presence of >50% of invasive carcinoma was observed in all sections of 66% of cases. Substantial necrosis (>50%) was present in <2% of samples. The concordance for the indicators targeted to validate the histopathology form was very high (kappa > 0.85) between first and last sections and fair to high between pathologists (kappa/pabak 0.21-0.72). The protocol allowed to correctly process without signs of contamination all FFPE of the study. The histopathology evaluation of the cases assured the presence of the targeted tissue, identified the presence of other tissues that could disturb the molecular diagnosis and allowed the assessment of tissue quality.

Five Data Validation Cases

ERIC Educational Resources Information Center

Simkin, Mark G.

2008-01-01

Data-validation routines enable computer applications to test data to ensure their accuracy, completeness, and conformance to industry or proprietary standards. This paper presents five programming cases that require students to validate five different types of data: (1) simple user data entries, (2) UPC codes, (3) passwords, (4) ISBN numbers, and…

Validation of two case definitions to identify pressure ulcers using hospital administrative data

PubMed Central

Ho, Chester; Jiang, Jason; Eastwood, Cathy A; Wong, Holly; Weaver, Brittany; Quan, Hude

2017-01-01

Objective Pressure ulcer development is a quality of care indicator, as pressure ulcers are potentially preventable. Yet pressure ulcer is a leading cause of morbidity, discomfort and additional healthcare costs for inpatients. Methods are lacking for accurate surveillance of pressure ulcer in hospitals to track occurrences and evaluate care improvement strategies. The main study aim was to validate hospital discharge abstract database (DAD) in recording pressure ulcers against nursing consult reports, and to calculate prevalence of pressure ulcers in Alberta, Canada in DAD. We hypothesised that a more inclusive case definition for pressure ulcers would enhance validity of cases identified in administrative data for research and quality improvement purposes. Setting A cohort of patients with pressure ulcers were identified from enterostomal (ET) nursing consult documents at a large university hospital in 2011. Participants There were 1217 patients with pressure ulcers in ET nursing documentation that were linked to a corresponding record in DAD to validate DAD for correct and accurate identification of pressure ulcer occurrence, using two case definitions for pressure ulcer. Results Using pressure ulcer definition 1 (7 codes), prevalence was 1.4%, and using definition 2 (29 codes), prevalence was 4.2% after adjusting for misclassifications. The results were lower than expected. Definition 1 sensitivity was 27.7% and specificity was 98.8%, while definition 2 sensitivity was 32.8% and specificity was 95.9%. Pressure ulcer in both DAD and ET consultation increased with age, number of comorbidities and length of stay. Conclusion DAD underestimate pressure ulcer prevalence. Since various codes are used to record pressure ulcers in DAD, the case definition with more codes captures more pressure ulcer cases, and may be useful for monitoring facility trends. However, low sensitivity suggests that this data source may not be accurate for determining overall prevalence, and should be cautiously compared with other prevalence studies. PMID:28851785

Persian adaptation of a questionnaire of environmental risk factors in multiple sclerosis (EnvIMS-Q).

PubMed

Sahraian, Mohammad Ali; Naghshineh, Hoda; Shati, Mohsen; Jahromi, Soodeh Razeghi; Rezaei, Niloofar

2016-11-01

It seems that gene-environment interaction play most important role in Multiple Sclerosis development. Increasing the incidence and prevalence of MS during the recent decades in the low prevalence area such as Iran is explained better by environment factors. Environmental Risk Factors in Multiple Sclerosis (the 'EnvIMS-Q') is a 6-page self-administered questionnaire for case control studies. the objectives of study are validation and adaptation of the EnvIMS-Q' then development of a Persian version for case control studies in Persian population. This questionnaire translated literally and in culturally relevant form, then content validation process was done by three groups' experts. According to giving rating to each item, each section and the whole instrument, we calculated their content validation indexes and also added some new questions and a new section to EnvIMS-Q. Finally, we analyzed repeatability of the answers within a 4 weeks interval. Relevancy and clarity indexes of all items were more than 80%. Scale relevancy index equaled 99% and scale clarity index equaled 97%. Repeatability of most items was acceptable. the use of standardized validated questionnaires will assist the researchers to perform local studies on the role of environmental factors on the basis of reliable data. Copyright © 2016 Elsevier B.V. All rights reserved.

A Framework for Testing Scientific Software: A Case Study of Testing Amsterdam Discrete Dipole Approximation Software

NASA Astrophysics Data System (ADS)

Shao, Hongbing

Software testing with scientific software systems often suffers from test oracle problem, i.e., lack of test oracles. Amsterdam discrete dipole approximation code (ADDA) is a scientific software system that can be used to simulate light scattering of scatterers of various types. Testing of ADDA suffers from "test oracle problem". In this thesis work, I established a testing framework to test scientific software systems and evaluated this framework using ADDA as a case study. To test ADDA, I first used CMMIE code as the pseudo oracle to test ADDA in simulating light scattering of a homogeneous sphere scatterer. Comparable results were obtained between ADDA and CMMIE code. This validated ADDA for use with homogeneous sphere scatterers. Then I used experimental result obtained for light scattering of a homogeneous sphere to validate use of ADDA with sphere scatterers. ADDA produced light scattering simulation comparable to the experimentally measured result. This further validated the use of ADDA for simulating light scattering of sphere scatterers. Then I used metamorphic testing to generate test cases covering scatterers of various geometries, orientations, homogeneity or non-homogeneity. ADDA was tested under each of these test cases and all tests passed. The use of statistical analysis together with metamorphic testing is discussed as a future direction. In short, using ADDA as a case study, I established a testing framework, including use of pseudo oracles, experimental results and the metamorphic testing techniques to test scientific software systems that suffer from test oracle problems. Each of these techniques is necessary and contributes to the testing of the software under test.

Care Case Managers' Job Satisfaction: a first contribution to the Italian validation of the Job Satisfaction Scale.

PubMed

Foà, Chiara; Bertinelli, Simona; Boschini, Anna; Fragnelli, Maria; Svichkar, Valentina; Tempone, Maria Rosaria; Sarli, Leopoldo; Giovanna Artioli, Giovanna

2016-05-26

Background and aims of the work: From the analysis of the Italian literature emerges a lack of studies both about the work satisfaction of Case Care Manager Nurses (CCMN) and on their role in the sanitary context. This research aims to fill this gap through a first Italian validation of the Job Satisfaction Scale (JSS). An Italian translation of JSS was provided by three independent judges. To verify the convergent validity of the scale the McCloskey Mueller Satisfaction Scale were used. A measure of the Organizational Wellbeing in the Operating Unit was used in order to verify the concurrent validity. A Professional Self-Efficacy evaluation allowed to verify the discriminant validity. Two open questions examined the role description and the difficulties met at work by the CCMN. The questionnaire was published on the Italian Association of Case Manager and in several Italian Professional Associations of Nurses, Sanitary Assistants and Pediatric nurses (IPASVI). 86 people (70 women) answered the questionnaire; 34 of which were Nurses and 52 CCMN. The convergent, the discriminant and the concurrent validity of the scale were proved. The participants were more satisfied with the quality and the kind of their job, and with the supervision and the colleagues, and less satisfied with the contingent recognitions, the marginal benefits, the promotions and with working and salary conditions. No relevant differences were found between Nurses and CCMN, but in authonomy, responsibility and professional opportunities the CCMN were more satisfied. This study aimed to offer a first validation contribution of the JSS Scale. Unfortunately the number of participants did not allow to testify a confirmatory factor analysis of the scale. Thus this work should be further improved. Finally, the data highlighted the need to investigate on the recognition of CCMN, since its absence is often the cause of a job dissatisfaction.

Effects of Older Brother-Younger Sister Incest: A Study of the Dynamics of 17 Cases.

ERIC Educational Resources Information Center

Laviola, Marisa

1992-01-01

This study of 17 cases of incest between siblings found the women commonly experienced mistrust of men and women, chronic low or negative self-esteem, sexual response difficulties, and intrusive thoughts of the incest. Individual therapy, talking with supportive family and friends, and validating themselves as victims were seen as helpful.…

Using natural language processing for identification of herpes zoster ophthalmicus cases to support population-based study.

PubMed

Zheng, Chengyi; Luo, Yi; Mercado, Cheryl; Sy, Lina; Jacobsen, Steven J; Ackerson, Brad; Lewin, Bruno; Tseng, Hung Fu

2018-06-19

Diagnosis codes are inadequate for accurately identifying herpes zoster ophthalmicus (HZO). There is significant lack of population-based studies on HZO due to the high expense of manual review of medical records. To assess whether HZO can be identified from the clinical notes using natural language processing (NLP). To investigate the epidemiology of HZO among HZ population based on the developed approach. A retrospective cohort analysis. A total of 49,914 southern California residents aged over 18 years, who had a new diagnosis of HZ. An NLP-based algorithm was developed and validated with the manually curated validation dataset (n=461). The algorithm was applied on over 1 million clinical notes associated with the study population. HZO versus non-HZO cases were compared by age, sex, race, and comorbidities. We measured the accuracy of NLP algorithm. NLP algorithm achieved 95.6% sensitivity and 99.3% specificity. Compared to the diagnosis codes, NLP identified significant more HZO cases among HZ population (13.9% versus 1.7%). Compared to the non-HZO group, the HZO group was older, had more males, had more Whites, and had more outpatient visits. We developed and validated an automatic method to identify HZO cases with high accuracy. As one of the largest studies on HZO, our finding emphasizes the importance of preventing HZ in the elderly population. This method can be a valuable tool to support population-based studies and clinical care of HZO in the era of big data. This article is protected by copyright. All rights reserved.

Directed Design of Experiments for Validating Probability of Detection Capability of a Testing System

NASA Technical Reports Server (NTRS)

Generazio, Edward R. (Inventor)

2012-01-01

A method of validating a probability of detection (POD) testing system using directed design of experiments (DOE) includes recording an input data set of observed hit and miss or analog data for sample components as a function of size of a flaw in the components. The method also includes processing the input data set to generate an output data set having an optimal class width, assigning a case number to the output data set, and generating validation instructions based on the assigned case number. An apparatus includes a host machine for receiving the input data set from the testing system and an algorithm for executing DOE to validate the test system. The algorithm applies DOE to the input data set to determine a data set having an optimal class width, assigns a case number to that data set, and generates validation instructions based on the case number.

Analytic Validation of Immunohistochemical Assays: A Comparison of Laboratory Practices Before and After Introduction of an Evidence-Based Guideline.

PubMed

Fitzgibbons, Patrick L; Goldsmith, Jeffrey D; Souers, Rhona J; Fatheree, Lisa A; Volmar, Keith E; Stuart, Lauren N; Nowak, Jan A; Astles, J Rex; Nakhleh, Raouf E

2017-09-01

- Laboratories must demonstrate analytic validity before any test can be used clinically, but studies have shown inconsistent practices in immunohistochemical assay validation. - To assess changes in immunohistochemistry analytic validation practices after publication of an evidence-based laboratory practice guideline. - A survey on current immunohistochemistry assay validation practices and on the awareness and adoption of a recently published guideline was sent to subscribers enrolled in one of 3 relevant College of American Pathologists proficiency testing programs and to additional nonsubscribing laboratories that perform immunohistochemical testing. The results were compared with an earlier survey of validation practices. - Analysis was based on responses from 1085 laboratories that perform immunohistochemical staining. Of 1057 responses, 65.4% (691) were aware of the guideline recommendations before this survey was sent and 79.9% (550 of 688) of those have already adopted some or all of the recommendations. Compared with the 2010 survey, a significant number of laboratories now have written validation procedures for both predictive and nonpredictive marker assays and specifications for the minimum numbers of cases needed for validation. There was also significant improvement in compliance with validation requirements, with 99% (100 of 102) having validated their most recently introduced predictive marker assay, compared with 74.9% (326 of 435) in 2010. The difficulty in finding validation cases for rare antigens and resource limitations were cited as the biggest challenges in implementing the guideline. - Dissemination of the 2014 evidence-based guideline validation practices had a positive impact on laboratory performance; some or all of the recommendations have been adopted by nearly 80% of respondents.

Advanced Risk Reduction Tool (ARRT) Special Case Study Report: Science and Engineering Technical Assessments (SETA) Program

NASA Technical Reports Server (NTRS)

Kirsch, Paul J.; Hayes, Jane; Zelinski, Lillian

2000-01-01

This special case study report presents the Science and Engineering Technical Assessments (SETA) team's findings for exploring the correlation between the underlying models of Advanced Risk Reduction Tool (ARRT) relative to how it identifies, estimates, and integrates Independent Verification & Validation (IV&V) activities. The special case study was conducted under the provisions of SETA Contract Task Order (CTO) 15 and the approved technical approach documented in the CTO-15 Modification #1 Task Project Plan.

Valid statistical inference methods for a case-control study with missing data.

PubMed

Tian, Guo-Liang; Zhang, Chi; Jiang, Xuejun

2018-04-01

The main objective of this paper is to derive the valid sampling distribution of the observed counts in a case-control study with missing data under the assumption of missing at random by employing the conditional sampling method and the mechanism augmentation method. The proposed sampling distribution, called the case-control sampling distribution, can be used to calculate the standard errors of the maximum likelihood estimates of parameters via the Fisher information matrix and to generate independent samples for constructing small-sample bootstrap confidence intervals. Theoretical comparisons of the new case-control sampling distribution with two existing sampling distributions exhibit a large difference. Simulations are conducted to investigate the influence of the three different sampling distributions on statistical inferences. One finding is that the conclusion by the Wald test for testing independency under the two existing sampling distributions could be completely different (even contradictory) from the Wald test for testing the equality of the success probabilities in control/case groups under the proposed distribution. A real cervical cancer data set is used to illustrate the proposed statistical methods.

Identification of patients at high risk for Clostridium difficile infection: development and validation of a risk prediction model in hospitalized patients treated with antibiotics.

PubMed

van Werkhoven, C H; van der Tempel, J; Jajou, R; Thijsen, S F T; Diepersloot, R J A; Bonten, M J M; Postma, D F; Oosterheert, J J

2015-08-01

To develop and validate a prediction model for Clostridium difficile infection (CDI) in hospitalized patients treated with systemic antibiotics, we performed a case-cohort study in a tertiary (derivation) and secondary care hospital (validation). Cases had a positive Clostridium test and were treated with systemic antibiotics before suspicion of CDI. Controls were randomly selected from hospitalized patients treated with systemic antibiotics. Potential predictors were selected from the literature. Logistic regression was used to derive the model. Discrimination and calibration of the model were tested in internal and external validation. A total of 180 cases and 330 controls were included for derivation. Age >65 years, recent hospitalization, CDI history, malignancy, chronic renal failure, use of immunosuppressants, receipt of antibiotics before admission, nonsurgical admission, admission to the intensive care unit, gastric tube feeding, treatment with cephalosporins and presence of an underlying infection were independent predictors of CDI. The area under the receiver operating characteristic curve of the model in the derivation cohort was 0.84 (95% confidence interval 0.80-0.87), and was reduced to 0.81 after internal validation. In external validation, consisting of 97 cases and 417 controls, the model area under the curve was 0.81 (95% confidence interval 0.77-0.85) and model calibration was adequate (Brier score 0.004). A simplified risk score was derived. Using a cutoff of 7 points, the positive predictive value, sensitivity and specificity were 1.0%, 72% and 73%, respectively. In conclusion, a risk prediction model was developed and validated, with good discrimination and calibration, that can be used to target preventive interventions in patients with increased risk of CDI. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

The Borderline Syndrome Index: a validation study using the personality assessment schedule.

PubMed

Marlowe, M J; O'Neill-Byrne, K; Lowe-Ponsford, F; Watson, J P

1996-01-01

This study examines the validity and screening properties of the Borderline Syndrome Index--BSI (developed in the USA) for categories of the Personality Assessment Schedule--PAS (developed in the UK). Patients were recruited by case control sampling. Chance corrected agreement between instruments and screening properties of the BSI were calculated. The BSI proved a moderately sensitive but non-specific screen. Questionnaire scores were highly correlated with symptom measures. The results do not support the validity of the BSI or its use as a screening instrument. BSI scores may be distorted by current symptoms.

Classification of case-II waters using hyperspectral (HICO) data over North Indian Ocean

NASA Astrophysics Data System (ADS)

Srinivasa Rao, N.; Ramarao, E. P.; Srinivas, K.; Deka, P. C.

2016-05-01

State of the art Ocean color algorithms are proven for retrieving the ocean constituents (chlorophyll-a, CDOM and Suspended Sediments) in case-I waters. However, these algorithms could not perform well at case-II waters because of the optical complexity. Hyperspectral data is found to be promising to classify the case-II waters. The aim of this study is to propose the spectral bands for future Ocean color sensors to classify the case-II waters. Study has been performed with Rrs's of HICO at estuaries of the river Indus and GBM of North Indian Ocean. Appropriate field samples are not available to validate and propose empirical models to retrieve concentrations. The sensor HICO is not currently operational to plan validation exercise. Aqua MODIS data at case-I and Case-II waters are used as complementary to in- situ. Analysis of Spectral reflectance curves suggests the band ratios of Rrs 484 nm and Rrs 581 nm, Rrs 490 nm and Rrs 426 nm to classify the Chlorophyll -a and CDOM respectively. Rrs 610 nm gives the best scope for suspended sediment retrieval. The work suggests the need for ocean color sensors with central wavelength's of 426, 484, 490, 581 and 610 nm to estimate the concentrations of Chl-a, Suspended Sediments and CDOM in case-II waters.

Real-world use of the risk-need-responsivity model and the level of service/case management inventory with community-supervised offenders.

PubMed

Dyck, Heather L; Campbell, Mary Ann; Wershler, Julie L

2018-06-01

The risk-need-responsivity model (RNR; Bonta & Andrews, 2017) has become a leading approach for effective offender case management, but field tests of this model are still required. The present study first assessed the predictive validity of the RNR-informed Level of Service/Case Management Inventory (LS/CMI; Andrews, Bonta, & Wormith, 2004) with a sample of Atlantic Canadian male and female community-supervised provincial offenders (N = 136). Next, the case management plans prepared from these LS/CMI results were analyzed for adherence to the principles of risk, need, and responsivity. As expected, the LS/CMI was a strong predictor of general recidivism for both males (area under the curve = .75, 95% confidence interval [.66, .85]), and especially females (area under the curve = .94, 95% confidence interval [.84, 1.00]), over an average 3.42-year follow-up period. The LS/CMI was predictive of time to recidivism, with lower risk cases taking longer to reoffend than higher risk cases. Despite the robust predictive validity of the LS/CMI, case management plans developed by probation officers generally reflected poor adherence to the RNR principles. These findings highlight the need for better training on how to transfer risk appraisal information from valid risk tools to case plans to better meet the best-practice principles of risk, need, and responsivity for criminal behavior risk reduction. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Validation of administrative case ascertainment algorithms for chronic childhood arthritis in Manitoba, Canada.

PubMed

Shiff, Natalie Jane; Oen, Kiem; Rabbani, Rasheda; Lix, Lisa M

2017-09-01

We validated case ascertainment algorithms for juvenile idiopathic arthritis (JIA) in the provincial health administrative databases of Manitoba, Canada. A population-based pediatric rheumatology clinical database from April 1st 1980 to March 31st 2012 was used to test case definitions in individuals diagnosed at ≤15 years of age. The case definitions varied the number of diagnosis codes (1, 2, or 3), time frame (1, 2 or 3 years), time between diagnoses (ever, >1 day, or ≥8 weeks), and physician specialty. Positive predictive value (PPV), sensitivity, and specificity with 95% confidence intervals (CIs) are reported. A case definition of 1 hospitalization or ≥2 diagnoses in 2 years by any provider ≥8 weeks apart using diagnosis codes for rheumatoid arthritis and ankylosing spondylitis produced a sensitivity of 89.2% (95% CI 86.8, 91.6), specificity of 86.3% (95% CI 83.0, 89.6), and PPV of 90.6% (95% CI 88.3, 92.9) when seronegative enthesopathy and arthropathy (SEA) was excluded as JIA; and sensitivity of 88.2% (95% CI 85.7, 90.7), specificity of 90.4% (95% CI 87.5, 93.3), and PPV of 93.9% (95% CI 92.0, 95.8) when SEA was included as JIA. This study validates case ascertainment algorithms for JIA in Canadian administrative health data using diagnosis codes for both rheumatoid arthritis (RA) and ankylosing spondylitis, to better reflect current JIA classification than codes for RA alone. Researchers will be able to use these results to define cohorts for population-based studies.

Developing a Brief Cross-Culturally Validated Screening Tool for Externalizing Disorders in Children

ERIC Educational Resources Information Center

Zwirs, Barbara W. C.; Burger, Huibert; Schulpen, Tom W. J.; Buitelaar, Jan K.

2008-01-01

The study aims at developing and validating a brief, easy-to-use screening instrument for teachers to predict externalizing disorders in children and recommending them for timely referral. The scores are compared between Dutch and non-Dutch immigrant children and a significant amount of cases for externalizing disorders were identified but sex and…

Transitioning from Software Requirements Models to Design Models

NASA Technical Reports Server (NTRS)

Lowry, Michael (Technical Monitor); Whittle, Jon

2003-01-01

Summary: 1. Proof-of-concept of state machine synthesis from scenarios - CTAS case study. 2. CTAS team wants to use the syntheses algorithm to validate trajectory generation. 3. Extending synthesis algorithm towards requirements validation: (a) scenario relationships' (b) methodology for generalizing/refining scenarios, and (c) interaction patterns to control synthesis. 4. Initial ideas tested on conflict detection scenarios.

Program Validation: Four Case Studies. A Brief Report on Four Projects and Their Experiences Before the Joint Dissemination Review Panel.

ERIC Educational Resources Information Center

Taylor, Nancy, Ed.

In an effort to clearly illustrate the most effective approach when seeking Joint Dissemination Review Panel (JDRP) validation, this report describes four different educational programs. A program involving prekindergarten special students, and a project entailing a systems approach for disadvantaged elementary school students, were awarded…

Students' and Teacher's Experiences of the Validity and Reliability of Assessment in a Bioscience Course

ERIC Educational Resources Information Center

Räisänen, Milla; Tuononen, Tarja; Postareff, Liisa; Hailikari, Telle; Virtanen, Viivi

2016-01-01

This case study explores the assessment of students' learning outcomes in a second-year lecture course in biosciences. The aim is to deeply explore the teacher's and the students' experiences of the validity and reliability of assessment and to compare those perspectives. The data were collected through stimulated recall interviews. The results…

Validation of the SCOFF questionnaire for screening of eating disorders among Mexican university students.

PubMed

Sanchez-Armass, Omar; Raffaelli, Marcela; Andrade, Flavia Cristina Drumond; Wiley, Angela R; Noyola, Aida Nacielli Morales; Arguelles, Alejandra Cepeda; Aradillas-Garcia, Celia

2017-03-01

To evaluate the criterion validity and diagnostic utility of the SCOFF, a brief eating disorder (ED) screening instrument, in a Mexican sample. The study was conducted in two phases in 2012. Phase I involved the administration of self-report measures [the SCOFF and the Eating Disorder Inventory-2, (EDI-2)] to 1057 students aged 17-56 years (M age = 21.0, SD = 3.4; 67 % female) from three colleges at the Universidad Autónoma de San Luis Potosí, Mexico. In Phase II, a random subsample of these students (n = 104) participated in the eating disorder examination, a structured interview that yields ED diagnoses. Analyses were conducted to evaluate the SCOFF's criterion validity by examining (a) correlations between scores on the SCOFF and the EDI-2 and (b) the SCOFF's ability to differentiate diagnosed ED cases and non-cases. EDI-2 subscales showed high correlations with the SCOFF scores proving initial evidence of criterion validity. A score of two points on the SCOFF optimized the sensitivity (78 %) and specificity (84 %). With this cutoff, the SCOFF correctly classified over half the cases (PPV = 58 %) and screened out the majority of non-cases (NPV = 93 %) providing further evidence of criterion validity. Analyses were repeated separately for men and women, yielding gender-specific information on the SCOFF's performance. Taken as a whole, results indicated that the SCOFF can be a useful tool for identifying Mexican university students who are at risk of eating disorders.

Autoantibodies to MUC1 glycopeptides cannot be used as a screening assay for early detection of breast, ovarian, lung or pancreatic cancer

PubMed Central

Burford, B; Gentry-Maharaj, A; Graham, R; Allen, D; Pedersen, J W; Nudelman, A S; Blixt, O; Fourkala, E O; Bueti, D; Dawnay, A; Ford, J; Desai, R; David, L; Trinder, P; Acres, B; Schwientek, T; Gammerman, A; Reis, C A; Silva, L; Osório, H; Hallett, R; Wandall, H H; Mandel, U; Hollingsworth, M A; Jacobs, I; Fentiman, I; Clausen, H; Taylor-Papadimitriou, J; Menon, U; Burchell, J M

2013-01-01

Background: Autoantibodies have been detected in sera before diagnosis of cancer leading to interest in their potential as screening/early detection biomarkers. As we have found autoantibodies to MUC1 glycopeptides to be elevated in early-stage breast cancer patients, in this study we analysed these autoantibodies in large population cohorts of sera taken before cancer diagnosis. Methods: Serum samples from women who subsequently developed breast cancer, and aged-matched controls, were identified from UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) and Guernsey serum banks to formed discovery and validation sets. These were screened on a microarray platform of 60mer MUC1 glycopeptides and recombinant MUC1 containing 16 tandem repeats. Additional case–control sets comprised of women who subsequently developed ovarian, pancreatic and lung cancer were also screened on the arrays. Results: In the discovery (273 cases, 273 controls) and the two validation sets (UKCTOCS 426 cases, 426 controls; Guernsey 303 cases and 606 controls), no differences were found in autoantibody reactivity to MUC1 tandem repeat peptide or glycoforms between cases and controls. Furthermore, no differences were observed between ovarian, pancreatic and lung cancer cases and controls. Conclusion: This robust, validated study shows autoantibodies to MUC1 peptide or glycopeptides cannot be used for breast, ovarian, lung or pancreatic cancer screening. This has significant implications for research on the use of MUC1 in cancer detection. PMID:23652307

Fatigue after stroke: the development and evaluation of a case definition.

PubMed

Lynch, Joanna; Mead, Gillian; Greig, Carolyn; Young, Archie; Lewis, Susan; Sharpe, Michael

2007-11-01

While fatigue after stroke is a common problem, it has no generally accepted definition. Our aim was to develop a case definition for post-stroke fatigue and to test its psychometric properties. A case definition with face validity and an associated structured interview was constructed. After initial piloting, the feasibility, reliability (test-retest and inter-rater) and concurrent validity (in relation to four fatigue severity scales) were determined in 55 patients with stroke. All participating patients provided satisfactory answers to all the case definition probe questions demonstrating its feasibility For test-retest reliability, kappa was 0.78 (95% CI, 0.57-0.94, P<.01) and for inter-rater reliability kappa was 0.80 (95% CI, 0.62-0.99, P<.01). Patients fulfilling the case definition also had substantially higher fatigue scores on four fatigue severity scales (P<.001) indicating concurrent validity. The proposed case definition is feasible to administer and reliable in practice, and there is evidence of concurrent validity. It requires further evaluation in different settings.

Relationships between the decoupled and coupled transfer functions: Theoretical studies and experimental validation

NASA Astrophysics Data System (ADS)

Wang, Zengwei; Zhu, Ping; Liu, Zhao

2018-01-01

A generalized method for predicting the decoupled transfer functions based on in-situ transfer functions is proposed. The method allows predicting the decoupled transfer functions using coupled transfer functions, without disassembling the system. Two ways to derive relationships between the decoupled and coupled transfer functions are presented. Issues related to immeasurability of coupled transfer functions are also discussed. The proposed method is validated by numerical and experimental case studies.

42 CFR 488.330 - Certification of compliance or noncompliance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... State survey agency may be followed by a Federal validation survey. (A) The State certifies the..., it is final, except in the case of a complaint or validation survey conducted by CMS, or CMS review... finding of noncompliance takes precedence over that of compliance. (ii) In the case of a validation survey...

42 CFR 488.330 - Certification of compliance or noncompliance.

Code of Federal Regulations, 2012 CFR

2012-10-01

... State survey agency may be followed by a Federal validation survey. (A) The State certifies the..., it is final, except in the case of a complaint or validation survey conducted by CMS, or CMS review... finding of noncompliance takes precedence over that of compliance. (ii) In the case of a validation survey...

42 CFR 488.330 - Certification of compliance or noncompliance.

Code of Federal Regulations, 2011 CFR

2011-10-01

... State survey agency may be followed by a Federal validation survey. (A) The State certifies the..., it is final, except in the case of a complaint or validation survey conducted by CMS, or CMS review... finding of noncompliance takes precedence over that of compliance. (ii) In the case of a validation survey...

42 CFR 488.330 - Certification of compliance or noncompliance.

Code of Federal Regulations, 2013 CFR

2013-10-01

... State survey agency may be followed by a Federal validation survey. (A) The State certifies the..., it is final, except in the case of a complaint or validation survey conducted by CMS, or CMS review... finding of noncompliance takes precedence over that of compliance. (ii) In the case of a validation survey...

42 CFR 488.330 - Certification of compliance or noncompliance.

Code of Federal Regulations, 2014 CFR

2014-10-01

... State survey agency may be followed by a Federal validation survey. (A) The State certifies the..., it is final, except in the case of a complaint or validation survey conducted by CMS, or CMS review... finding of noncompliance takes precedence over that of compliance. (ii) In the case of a validation survey...

Case managers' expectations about employment for people with psychiatric disabilities.

PubMed

Abraham, Kristen M; Stein, Catherine H

2009-01-01

The importance of employment in lives of people with psychiatric disabilities is well documented. Yet, the role of case managers in facilitating or inhibiting employment opportunities for consumers is only beginning to be understood. This study examined the psychometric properties of a newly developed self-report measure designed to assess case managers' employment-related expectations of consumers. Psychometric properties of a 24-item self-report measure, Expectations for the Employability of People with Serious Mental Illness (EESMI), were examined using a sample of 107 case managers. EESMI items tap individual and social systems factors related to employment for people with psychiatric disabilities. Construct validity was assessed by relationships between EESMI scores and scores on measures of general expectations and opinions of people with serious mental illness, case manager burnout, and social desirability. EESMI consists of three empirically derived subscales with good internal consistency. Case managers' scores on EESMI correlated positively with scores on general expectations and opinions about people with mental illness scales and were generally unrelated to social desirability scores. EESMI scores were positively related to case managers' perceptions of the employability of consumers on their caseloads. EESMI is a psychometrically sound measure of mental health professionals' employment-related expectations of consumers. Reliable and valid assessment is basic to the study of mental health professionals' role in increasing employment opportunities for people with psychiatric disabilities. Study limitations and directions for future research are discussed.

A design of experiments approach to validation sampling for logistic regression modeling with error-prone medical records.

PubMed

Ouyang, Liwen; Apley, Daniel W; Mehrotra, Sanjay

2016-04-01

Electronic medical record (EMR) databases offer significant potential for developing clinical hypotheses and identifying disease risk associations by fitting statistical models that capture the relationship between a binary response variable and a set of predictor variables that represent clinical, phenotypical, and demographic data for the patient. However, EMR response data may be error prone for a variety of reasons. Performing a manual chart review to validate data accuracy is time consuming, which limits the number of chart reviews in a large database. The authors' objective is to develop a new design-of-experiments-based systematic chart validation and review (DSCVR) approach that is more powerful than the random validation sampling used in existing approaches. The DSCVR approach judiciously and efficiently selects the cases to validate (i.e., validate whether the response values are correct for those cases) for maximum information content, based only on their predictor variable values. The final predictive model will be fit using only the validation sample, ignoring the remainder of the unvalidated and unreliable error-prone data. A Fisher information based D-optimality criterion is used, and an algorithm for optimizing it is developed. The authors' method is tested in a simulation comparison that is based on a sudden cardiac arrest case study with 23 041 patients' records. This DSCVR approach, using the Fisher information based D-optimality criterion, results in a fitted model with much better predictive performance, as measured by the receiver operating characteristic curve and the accuracy in predicting whether a patient will experience the event, than a model fitted using a random validation sample. The simulation comparisons demonstrate that this DSCVR approach can produce predictive models that are significantly better than those produced from random validation sampling, especially when the event rate is low. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

From Marginalized to Validated: An In-Depth Case Study of an Asian American, Native American and Pacific Islander Serving Institution

ERIC Educational Resources Information Center

Nguyen, Thai-Huy; Nguyen, Mike Hoa; Nguyen, Bach Mai Dolly; Gasman, Marybeth; Conrad, Clifton

2018-01-01

This article highlights the capacity of an Asian American, Native American and Pacific Islander Institution (AANAPISI) to serve as an institutional convertor--by addressing challenges commonly associated with marginalized students--for low-income, Asian American and Pacific Islander students entering college. Through an in-depth case study, we…

A Pedagogical Trebuchet: A Case Study in Experimental History and History Pedagogy

ERIC Educational Resources Information Center

Brice, Lee L.; Catania, Steven

2012-01-01

A common problem history teachers face regardless of their field of specialization is how to help students find answers to the most difficult historical questions, those for which the sources are unavailable or inaccessible, and teach them to do so in a methodologically valid manner. This article presents a case study which shows how a project in…

An Insider Perspective on Implementing the Harvard Case Study Method in Business Teaching

ERIC Educational Resources Information Center

Rebeiz, Karim S.

2011-01-01

This paper provides practical guidance on the implementation of the CSM (case study method) using the HBS (Harvard Business School) model. The analysis is based on the first-hand experience of the author as a user and implementer of this mode of instruction. The results are further validated with surveys given to MBA (Master of Business…

Game Coaching System Design and Development: A Retrospective Case Study of FPS Trainer

ERIC Educational Resources Information Center

Tan, Wee Hoe

2013-01-01

This paper is a retrospective case study of a game-based learning (GBL) researcher who cooperated with a professional gamer and a team of game developers to design and develop a coaching system for First-Person Shooter (FPS) players. The GBL researcher intended to verify the ecological validity of a model of cooperation; the developers wanted to…

Risk prediction in the community: A systematic review of case-finding instruments that predict adverse healthcare outcomes in community-dwelling older adults.

PubMed

O'Caoimh, Rónán; Cornally, Nicola; Weathers, Elizabeth; O'Sullivan, Ronan; Fitzgerald, Carol; Orfila, Francesc; Clarnette, Roger; Paúl, Constança; Molloy, D William

2015-09-01

Few case-finding instruments are available to community healthcare professionals. This review aims to identify short, valid instruments that detect older community-dwellers risk of four adverse outcomes: hospitalisation, functional-decline, institutionalisation and death. Data sources included PubMed and the Cochrane library. Data on outcome measures, patient and instrument characteristics, and trial quality (using the Quality In Prognosis Studies [QUIPS] tool), were double-extracted for derivation-validation studies in community-dwelling older adults (>50 years). Forty-six publications, representing 23 unique instruments, were included. Only five were externally validated. Mean patient age range was 64.2-84.6 years. Most instruments n=18, (78%) were derived in North America from secondary analysis of survey data. The majority n=12, (52%), measured more than one outcome with hospitalisation and the Probability of Repeated Admission score the most studied outcome and instrument respectively. All instruments incorporated multiple predictors. Activities of daily living n=16, (70%), was included most often. Accuracy varied according to instruments and outcomes; area under the curve of 0.60-0.73 for hospitalisation, 0.63-0.78 for functional decline, 0.70-0.74 for institutionalisation and 0.56-0.82 for death. The QUIPS tool showed that 5/23 instruments had low potential for bias across all domains. This review highlights the present need to develop short, reliable, valid instruments to case-find older adults at risk in the community. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

A comparison of single- and multi-site calibration and validation: a case study of SWAT in the Miyun Reservoir watershed, China

NASA Astrophysics Data System (ADS)

Bai, Jianwen; Shen, Zhenyao; Yan, Tiezhu

2017-09-01

An essential task in evaluating global water resource and pollution problems is to obtain the optimum set of parameters in hydrological models through calibration and validation. For a large-scale watershed, single-site calibration and validation may ignore spatial heterogeneity and may not meet the needs of the entire watershed. The goal of this study is to apply a multi-site calibration and validation of the Soil andWater Assessment Tool (SWAT), using the observed flow data at three monitoring sites within the Baihe watershed of the Miyun Reservoir watershed, China. Our results indicate that the multi-site calibration parameter values are more reasonable than those obtained from single-site calibrations. These results are mainly due to significant differences in the topographic factors over the large-scale area, human activities and climate variability. The multi-site method involves the division of the large watershed into smaller watersheds, and applying the calibrated parameters of the multi-site calibration to the entire watershed. It was anticipated that this case study could provide experience of multi-site calibration in a large-scale basin, and provide a good foundation for the simulation of other pollutants in followup work in the Miyun Reservoir watershed and other similar large areas.

Validation of a track repeating algorithm for intensity modulated proton therapy: clinical cases study

NASA Astrophysics Data System (ADS)

Yepes, Pablo P.; Eley, John G.; Liu, Amy; Mirkovic, Dragan; Randeniya, Sharmalee; Titt, Uwe; Mohan, Radhe

2016-04-01

Monte Carlo (MC) methods are acknowledged as the most accurate technique to calculate dose distributions. However, due its lengthy calculation times, they are difficult to utilize in the clinic or for large retrospective studies. Track-repeating algorithms, based on MC-generated particle track data in water, accelerate dose calculations substantially, while essentially preserving the accuracy of MC. In this study, we present the validation of an efficient dose calculation algorithm for intensity modulated proton therapy, the fast dose calculator (FDC), based on a track-repeating technique. We validated the FDC algorithm for 23 patients, which included 7 brain, 6 head-and-neck, 5 lung, 1 spine, 1 pelvis and 3 prostate cases. For validation, we compared FDC-generated dose distributions with those from a full-fledged Monte Carlo based on GEANT4 (G4). We compared dose-volume-histograms, 3D-gamma-indices and analyzed a series of dosimetric indices. More than 99% of the voxels in the voxelized phantoms describing the patients have a gamma-index smaller than unity for the 2%/2 mm criteria. In addition the difference relative to the prescribed dose between the dosimetric indices calculated with FDC and G4 is less than 1%. FDC reduces the calculation times from 5 ms per proton to around 5 μs.

Facilitating Case Studies in Massage Therapy Clinical Education

PubMed Central

Baskwill, Amanda

2013-01-01

The integration of evidence into reflective health care practice has been on the rise in recent years and is a phenomenon that has affected all health care professions, including massage therapy. Clinical case studies are a research design that follows one patient or subject, making the studies ideal for use in clinical practice. They are valuable for communicating information from clinical practice to the broader community. Case studies have face validity that may be more valuable to individual practitioners than homogeneous randomized controlled trials, as the practitioner may recognize a complex patient in the case report. At Humber College, Student Massage Therapists (SMTs) create, conduct, and communicate results of a clinical case study prior to graduation. This article describes the process and experience. PMID:23730397

Second-Order Factor Analysis as a Validity Assessment Tool: A Case Study Example Involving Perceptions of Stereotypic Love.

ERIC Educational Resources Information Center

Borrello, Gloria M.; Thompson, Bruce

The calculation of second-order results in the validity assessment of measures and some useful interpretation aids are presented. First-order and second-order results give different and informative pictures of data dynamics. Several aspects of good practice in interpretation of second-order results are presented using data from 487 subjects…

Construct Validity and Reliability of the Tolerance Scale among Iranian College Students

ERIC Educational Resources Information Center

Ersanli, Ercümend; Mameghani, Shiva Saeighi

2016-01-01

In the present study, the Tolerance Scale developed by Ersanli (2014) was adapted to the Iranian culture, and its validity and reliability were investigated in the case of Iranian college students. The participants consisted of 552 Iranian college students (62% male, M = 20.84, S.D.: 1.53) selected using the convenience sampling method. The sample…

Content Validity of Game-Based Assessment: Case Study of a Serious Game for ICT Managers in Training

ERIC Educational Resources Information Center

Hummel, Hans G. K.; Joosten-ten Brinke, Desirée; Nadolski, Rob J.; Baartman, Liesbeth K. J.

2017-01-01

Serious games foster the acquisition of complex problem-solving skills. Assessment of such skills should be in line with instruction, and within a serious game environment its content validity should equal face-to-face assessment. Research on assessment in serious gaming has remained rather scarce. This article shows how assessment can be…

A reliability and validity study of the Palliative Performance Scale

PubMed Central

Ho, Francis; Lau, Francis; Downing, Michael G; Lesperance, Mary

2008-01-01

Background The Palliative Performance Scale (PPS) was first introduced in1996 as a new tool for measurement of performance status in palliative care. PPS has been used in many countries and has been translated into other languages. Methods This study evaluated the reliability and validity of PPS. A web-based, case scenarios study with a test-retest format was used to determine reliability. Fifty-three participants were recruited and randomly divided into two groups, each evaluating 11 cases at two time points. The validity study was based on the content validation of 15 palliative care experts conducted over telephone interviews, with discussion on five themes: PPS as clinical assessment tool, the usefulness of PPS, PPS scores affecting decision making, the problems in using PPS, and the adequacy of PPS instruction. Results The intraclass correlation coefficients for absolute agreement were 0.959 and 0.964 for Group 1, at Time-1 and Time-2; 0.951 and 0.931 for Group 2, at Time-1 and Time-2 respectively. Results showed that the participants were consistent in their scoring over the two times, with a mean Cohen's kappa of 0.67 for Group 1 and 0.71 for Group 2. In the validity study, all experts agreed that PPS is a valuable clinical assessment tool in palliative care. Many of them have already incorporated PPS as part of their practice standard. Conclusion The results of the reliability study demonstrated that PPS is a reliable tool. The validity study found that most experts did not feel a need to further modify PPS and, only two experts requested that some performance status measures be defined more clearly. Areas of PPS use include prognostication, disease monitoring, care planning, hospital resource allocation, clinical teaching and research. PPS is also a good communication tool between palliative care workers. PMID:18680590

Validation of verbal autopsy methods using hospital medical records: a case study in Vietnam.

PubMed

Tran, Hong Thi; Nguyen, Hoa Phuong; Walker, Sue M; Hill, Peter S; Rao, Chalapati

2018-05-18

Information on causes of death (COD) is crucial for measuring the health outcomes of populations and progress towards the Sustainable Development Goals. In many countries such as Vietnam where the civil registration and vital statistics (CRVS) system is dysfunctional, information on vital events will continue to rely on verbal autopsy (VA) methods. This study assesses the validity of VA methods used in Vietnam, and provides recommendations on methods for implementing VA validation studies in Vietnam. This validation study was conducted on a sample of 670 deaths from a recent VA study in Quang Ninh province. The study covered 116 cases from this sample, which met three inclusion criteria: a) the death occurred within 30 days of discharge after last hospitalisation, and b) medical records (MRs) for the deceased were available from respective hospitals, and c) the medical record mentioned that the patient was terminally ill at discharge. For each death, the underlying cause of death (UCOD) identified from MRs was compared to the UCOD from VA. The validity of VA diagnoses for major causes of death was measured using sensitivity, specificity and positive predictive value (PPV). The sensitivity of VA was at least 75% in identifying some leading CODs such as stroke, road traffic accidents and several site-specific cancers. However, sensitivity was less than 50% for other important causes including ischemic heart disease, chronic obstructive pulmonary diseases, and diabetes. Overall, there was 57% agreement between UCOD from VA and MR, which increased to 76% when multiple causes from VA were compared to UCOD from MR. Our findings suggest that VA is a valid method to ascertain UCOD in contexts such as Vietnam. Furthermore, within cultural contexts in which patients prefer to die at home instead of a healthcare facility, using the available MRs as the gold standard may be meaningful to the extent that recall bias from the interval between last hospital discharge and death can be minimized. Therefore, future studies should evaluate validity of MRs as a gold standard for VA studies in contexts similar to the Vietnamese context.

FAST Model Calibration and Validation of the OC5- DeepCwind Floating Offshore Wind System Against Wave Tank Test Data: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wendt, Fabian F; Robertson, Amy N; Jonkman, Jason

During the course of the Offshore Code Comparison Collaboration, Continued, with Correlation (OC5) project, which focused on the validation of numerical methods through comparison against tank test data, the authors created a numerical FAST model of the 1:50-scale DeepCwind semisubmersible system that was tested at the Maritime Research Institute Netherlands ocean basin in 2013. This paper discusses several model calibration studies that were conducted to identify model adjustments that improve the agreement between the numerical simulations and the experimental test data. These calibration studies cover wind-field-specific parameters (coherence, turbulence), hydrodynamic and aerodynamic modeling approaches, as well as rotor model (blade-pitchmore » and blade-mass imbalances) and tower model (structural tower damping coefficient) adjustments. These calibration studies were conducted based on relatively simple calibration load cases (wave only/wind only). The agreement between the final FAST model and experimental measurements is then assessed based on more-complex combined wind and wave validation cases.« less

Retrospective Validation of a Surveillance System for Unexplained Illness and Death: New Haven County, Connecticut

PubMed Central

Kluger, Michael D.; Sofair, Andre N.; Heye, Constance J.; Meek, James I.; Sodhi, Rajesh K.; Hadler, James L.

2001-01-01

Objectives. This study investigated retrospective validation of a prospective surveillance system for unexplained illness and death due to possibly infectious causes. Methods. A computerized search of hospital discharge data identified patients with potential unexplained illness and death due to possibly infectious causes. Medical records for such patients were reviewed for satisfaction of study criteria. Cases identified retrospectively were combined with prospectively identified cases to form a reference population against which sensitivity could be measured. Results. Retrospective validation was 41% sensitive, whereas prospective surveillance was 73% sensitive. The annual incidence of unexplained illness and death due to possibly infectious causes during 1995 and 1996 in the study county was conservatively estimated to range from 2.7 to 6.2 per 100 000 residents aged 1 to 49 years. Conclusions. Active prospective surveillance for unexplained illness and death due to possibly infectious causes is more sensitive than retrospective surveillance conducted through a published list of indicator codes. However, retrospective surveillance can be a feasible and much less labor-intensive alternative to active prospective surveillance when the latter is not possible or desired. PMID:11499106

The use of administrative health care databases to identify patients with rheumatoid arthritis

PubMed Central

Hanly, John G; Thompson, Kara; Skedgel, Chris

2015-01-01

Objective To validate and compare the decision rules to identify rheumatoid arthritis (RA) in administrative databases. Methods A study was performed using administrative health care data from a population of 1 million people who had access to universal health care. Information was available on hospital discharge abstracts and physician billings. RA cases in health administrative databases were matched 1:4 by age and sex to randomly selected controls without inflammatory arthritis. Seven case definitions were applied to identify RA cases in the health administrative data, and their performance was compared with the diagnosis by a rheumatologist. The validation study was conducted on a sample of individuals with administrative data who received a rheumatologist consultation at the Arthritis Center of Nova Scotia. Results We identified 535 RA cases and 2,140 non-RA, noninflammatory arthritis controls. Using the rheumatologist’s diagnosis as the gold standard, the overall accuracy of the case definitions for RA cases varied between 68.9% and 82.9% with a kappa statistic between 0.26 and 0.53. The sensitivity and specificity varied from 20.7% to 94.8% and 62.5% to 98.5%, respectively. In a reference population of 1 million, the estimated annual number of incident cases of RA was between 176 and 1,610 and the annual number of prevalent cases was between 1,384 and 5,722. Conclusion The accuracy of case definitions for the identification of RA cases from rheumatology clinics using administrative health care databases is variable when compared to a rheumatologist’s assessment. This should be considered when comparing results across studies. This variability may also be used as an advantage in different study designs, depending on the relative importance of sensitivity and specificity for identifying the population of interest to the research question. PMID:27790047

Reliability, Validity, and Usability of Data Extraction Programs for Single-Case Research Designs.

PubMed

Moeyaert, Mariola; Maggin, Daniel; Verkuilen, Jay

2016-11-01

Single-case experimental designs (SCEDs) have been increasingly used in recent years to inform the development and validation of effective interventions in the behavioral sciences. An important aspect of this work has been the extension of meta-analytic and other statistical innovations to SCED data. Standard practice within SCED methods is to display data graphically, which requires subsequent users to extract the data, either manually or using data extraction programs. Previous research has examined issues of reliability and validity of data extraction programs in the past, but typically at an aggregate level. Little is known, however, about the coding of individual data points. We focused on four different software programs that can be used for this purpose (i.e., Ungraph, DataThief, WebPlotDigitizer, and XYit), and examined the reliability of numeric coding, the validity compared with real data, and overall program usability. This study indicates that the reliability and validity of the retrieved data are independent of the specific software program, but are dependent on the individual single-case study graphs. Differences were found in program usability in terms of user friendliness, data retrieval time, and license costs. Ungraph and WebPlotDigitizer received the highest usability scores. DataThief was perceived as unacceptable and the time needed to retrieve the data was double that of the other three programs. WebPlotDigitizer was the only program free to use. As a consequence, WebPlotDigitizer turned out to be the best option in terms of usability, time to retrieve the data, and costs, although the usability scores of Ungraph were also strong. © The Author(s) 2016.

Development and Validation of a Novel Robotic Procedure Specific Simulation Platform: Partial Nephrectomy.

PubMed

Hung, Andrew J; Shah, Swar H; Dalag, Leonard; Shin, Daniel; Gill, Inderbir S

2015-08-01

We developed a novel procedure specific simulation platform for robotic partial nephrectomy. In this study we prospectively evaluate its face, content, construct and concurrent validity. This hybrid platform features augmented reality and virtual reality. Augmented reality involves 3-dimensional robotic partial nephrectomy surgical videos overlaid with virtual instruments to teach surgical anatomy, technical skills and operative steps. Advanced technical skills are assessed with an embedded full virtual reality renorrhaphy task. Participants were classified as novice (no surgical training, 15), intermediate (less than 100 robotic cases, 13) or expert (100 or more robotic cases, 14) and prospectively assessed. Cohort performance was compared with the Kruskal-Wallis test (construct validity). Post-study questionnaire was used to assess the realism of simulation (face validity) and usefulness for training (content validity). Concurrent validity evaluated correlation between virtual reality renorrhaphy task and a live porcine robotic partial nephrectomy performance (Spearman's analysis). Experts rated the augmented reality content as realistic (median 8/10) and helpful for resident/fellow training (8.0-8.2/10). Experts rated the platform highly for teaching anatomy (9/10) and operative steps (8.5/10) but moderately for technical skills (7.5/10). Experts and intermediates outperformed novices (construct validity) in efficiency (p=0.0002) and accuracy (p=0.002). For virtual reality renorrhaphy, experts outperformed intermediates on GEARS metrics (p=0.002). Virtual reality renorrhaphy and in vivo porcine robotic partial nephrectomy performance correlated significantly (r=0.8, p <0.0001) (concurrent validity). This augmented reality simulation platform displayed face, content and construct validity. Performance in the procedure specific virtual reality task correlated highly with a porcine model (concurrent validity). Future efforts will integrate procedure specific virtual reality tasks and their global assessment. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Validation of Robotic Surgery Simulator (RoSS).

PubMed

Kesavadas, Thenkurussi; Stegemann, Andrew; Sathyaseelan, Gughan; Chowriappa, Ashirwad; Srimathveeravalli, Govindarajan; Seixas-Mikelus, Stéfanie; Chandrasekhar, Rameella; Wilding, Gregory; Guru, Khurshid

2011-01-01

Recent growth of daVinci Robotic Surgical System as a minimally invasive surgery tool has led to a call for better training of future surgeons. In this paper, a new virtual reality simulator, called RoSS is presented. Initial results from two studies - face and content validity, are very encouraging. 90% of the cohort of expert robotic surgeons felt that the simulator was excellent or somewhat close to the touch and feel of the daVinci console. Content validity of the simulator received 90% approval in some cases. These studies demonstrate that RoSS has the potential of becoming an important training tool for the daVinci surgical robot.

The obsessive compulsive drinking scale is a valid measure of alcohol craving in young adults.

PubMed

Connor, Jason P; Feeney, Gerald F X; Jack, Alyssa; Young, Ross McD

2010-12-01

Alcohol craving is associated with greater alcohol-related problems and less favorable treatment prognosis. The Obsessive Compulsive Drinking Scale (OCDS) is the most widely used alcohol craving instrument. The OCDS has been validated in adults with alcohol use disorders (AUDs), which typically emerge in early adulthood. This study examines the validity of the OCDS in a nonclinical sample of young adults. Three hundred and nine college students (mean age of 21.8 years, SD = 4.6 years) completed the OCDS, Alcohol Use Disorders Identification Test (AUDIT), and measures of alcohol consumption. Subjects were randomly allocated to 2 samples. Construct validity was examined via exploratory factor analysis (n = 155) and confirmatory factor analysis (n = 154). Concurrent validity was assessed using the AUDIT and measures of alcohol consumption. A second, alcohol-dependent sample (mean age 42 years, SD 12 years) from a previously published study (n = 370) was used to assess discriminant validity. A unique young adult OCDS factor structure was validated, consisting of Interference/Control, Frequency of Obsessions, Alcohol Consumption and Resisting Obsessions/Compulsions. The young adult 4-factor structure was significantly associated with the AUDIT and alcohol consumption. The 4 factor OCDS successfully classified nonclinical subjects in 96.9% of cases and the older alcohol-dependent patients in 83.7% of cases. Although the OCDS was able to classify college nonproblem drinkers (AUDIT <13, n = 224) with 83.2% accuracy, it was no better than chance (49.4%) in classifying potential college problem drinkers (AUDIT score ≥13, n = 85). Using the 4-factor structure, the OCDS is a valid measure of alcohol craving in young adult populations. In this nonclinical set of students, the OCDS classified nonproblem drinkers well but not problem drinkers. Studies need to further examine the utility of the OCDS in young people with alcohol misuse. Copyright © 2010 by the Research Society on Alcoholism.

A validational study of the Ironson-Woods Spirituality/Religiousness Index in Nigerian adolescents.

PubMed

Otakpor, Alex N; Akanni, Oluyemi O

2015-01-01

The mental health impact of spirituality/religiousness is widely recognised and studied in Western countries, but less so in developing nations, partly because of lack of valid instruments for such studies. The objective of the study was to determine the convergent validity of the Ironson-Woods Spirituality/Religiousness Index (IWSRI) in school attending Nigerian adolescents, and any relationship between spirituality/religiousness and mental health status. The 25-item IWSRI, the "Age Universal" Religious Orientation Scale (ROS) and the 28-item General Health Questionnaire (GHQ) were administered to 300 randomly selected final year senior secondary students, aged 16 to 19 years, in Benin City. Responses were analysed using SPSS version 16 to determine the internal consistency for reliability, and correlation scores for convergent validity, of the IWSRI. Cronbach's alpha for the total IWSRI scale was 0.91; and for each of the two spirituality and two religiousness subscales of the IWSRI, these were quite high as well. The correlation of IWSRI with ROS intrinsic (r=0.47, p=0.00) and extrinsic personal religiosity (r=0.22, p=0.00) were significant. There was a significant difference in the IWSRI mean scores of GHQ cases and non-cases (t=4.30, p=0.00). IWSRI has acceptable psychometric properties, and therefore applicable in measuring spirituality and religiousness in Nigerian adolescents.

Development and Validation of a Simple Risk Score for Undiagnosed Type 2 Diabetes in a Resource-Constrained Setting

PubMed Central

Gilman, Robert H.; Sanchez-Abanto, Jose R.; Study Group, CRONICAS Cohort

2016-01-01

Objective. To develop and validate a risk score for detecting cases of undiagnosed diabetes in a resource-constrained country. Methods. Two population-based studies in Peruvian population aged ≥35 years were used in the analysis: the ENINBSC survey (n = 2,472) and the CRONICAS Cohort Study (n = 2,945). Fasting plasma glucose ≥7.0 mmol/L was used to diagnose diabetes in both studies. Coefficients for risk score were derived from the ENINBSC data and then the performance was validated using both baseline and follow-up data of the CRONICAS Cohort Study. Results. The prevalence of undiagnosed diabetes was 2.0% in the ENINBSC survey and 2.9% in the CRONICAS Cohort Study. Predictors of undiagnosed diabetes were age, diabetes in first-degree relatives, and waist circumference. Score values ranged from 0 to 4, with an optimal cutoff ≥2 and had a moderate performance when applied in the CRONICAS baseline data (AUC = 0.68; 95% CI: 0.62–0.73; sensitivity 70%; specificity 59%). When predicting incident cases, the AUC was 0.66 (95% CI: 0.61–0.71), with a sensitivity of 69% and specificity of 59%. Conclusions. A simple nonblood based risk score based on age, diabetes in first-degree relatives, and waist circumference can be used as a simple screening tool for undiagnosed and incident cases of diabetes in Peru. PMID:27689096

A systematic literature review of US definitions, scoring systems and validity according to the OMERACT filter for tendon lesion in RA and other inflammatory joint diseases.

PubMed

Alcalde, María; D'Agostino, Maria Antonietta; Bruyn, George A W; Möller, Ingrid; Iagnocco, Annamaria; Wakefield, Richard J; Naredo, Esperanza

2012-07-01

To present the published data concerning the US assessment of tendon lesions as well as the US metric properties investigated in inflammatory arthritis. A systematic literature search of PubMed, Embase and the Cochrane Library was performed. Selection criteria were original articles in the English language reporting US, Doppler, tenosynovitis and other tendon lesions in patients with RA and other inflammatory arthritis. Data extraction focused on the definition and quantification of US-detected tenosynovitis and other tendon abnormalities and the metric properties of US according to the OMERACT filter for evaluating the above tendon lesions. Thirty-three of 192 identified articles were included in the review. Most articles were case series (42%) or case-control (33%) studies describing hand and/or foot tenosynovitis in RA patients. The majority of older articles used only B-mode, whereas the most recent studies have incorporated Doppler mode. Definition of tenosynovitis or other tendon lesion was provided in 70% of the evaluated studies. Most of the studies (61%) used a binary score for evaluating tendon abnormalities. Concerning the OMERACT filter, 24 (73%) articles dealt with construct validity. The comparator most commonly used was clinical assessment and MRI. There were few studies assessing criterion validity. Some studies evaluated reliability (36%), responsiveness (21%) and feasibility (12%). US seems a promising tool for evaluating inflammatory tendon lesions. However, further validation is necessary for implementation in clinical practice and trials.

Validating an artificial intelligence human proximity operations system with test cases

NASA Astrophysics Data System (ADS)

Huber, Justin; Straub, Jeremy

2013-05-01

An artificial intelligence-controlled robot (AICR) operating in close proximity to humans poses risk to these humans. Validating the performance of an AICR is an ill posed problem, due to the complexity introduced by the erratic (noncomputer) actors. In order to prove the AICR's usefulness, test cases must be generated to simulate the actions of these actors. This paper discusses AICR's performance validation in the context of a common human activity, moving through a crowded corridor, using test cases created by an AI use case producer. This test is a two-dimensional simplification relevant to autonomous UAV navigation in the national airspace.

Comparative study of control selection in a national population-based case-control study: Estimating risk of smoking on cancer deaths in Chinese men.

PubMed

Jiang, Jingmei; Liu, Boqi; Nasca, Philip C; Han, Wei; Zou, Xiaonong; Zeng, Xianjia; Tian, Xiaobing; Wu, Yanping; Zhao, Ping; Li, Junyao

2009-10-28

To assess the validation of a novel control selection design by comparing the consistency between the new design and a routine design in a large case-control study that was incorporated into a nationwide mortality survey in China. A nationwide mortality study was conducted during 1989-1991. Surviving spouses or other relatives of all adults who died during 1986-1988 provided detailed information about their own as well as the deceased person's smoking history. In this study, 130,079 males who died of various smoking-related cancers at age 35 or over were taken as cases, while 103,248 male surviving spouses (same age range with cases) of women who died during the same period and 49,331 males who died from causes other than those related to smoking were used as control group 1 and control group 2, respectively. Consistency in the results when comparing cases with each of the control groups was assessed. Consistency in the results was observed in the analyses using different control groups although cancer deaths varied with region and age. Equivalence could be ascertained using a 15% criterion in most cancer deaths which had high death rates in urban areas, but they were uncertain for most cancers in rural areas irrespective of whether the hypothesis testing showed significant differences or not. Sex-matched living spouse control design as an alternative control selection for a case-control study is valid and feasible, and the basic principles of the equivalence study are also supported by epidemiological survey data.

Iridology: A systematic review.

PubMed

Ernst, E

1999-02-01

Iridologists claim to be able to diagnose medical conditions through abnormalities of pigmentation in the iris. This technique is popular in many countries. Therefore it is relevant to ask whether it is valid. To systematically review all interpretable tests of the validity of iridology as a diagnostic tool. DATA SOURCE AND EXTRACTION: Three independent literature searches were performed to identify all blinded tests. Data were extracted in a predefined, standardized fashion. Four case control studies were found. The majority of these investigations suggests that iridology is not a valid diagnostic method. The validity of iridology as a diagnostic tool is not supported by scientific evaluations. Patients and therapists should be discouraged from using this method.

Expanded Awareness of Student Performance: A Case Study in Applied Ethnographic Monitoring in a Bilingual Classroom. Sociolinguistic Working Paper Number 60.

ERIC Educational Resources Information Center

Carrasco, Robert L.

The case study of the use of a classroom observation technique to evaluate the abilities and performance of a bilingual kindergarten student previously assessed as a low achiever is described. There are three objectives: to show the validity of the ethnographic monitoring technique, to show the value of teachers as collaborating researchers, and…

To Produce Conjectures and to Prove Them within a Dynamic Geometry Environment: A Case Study

ERIC Educational Resources Information Center

Furinghetti, Fulvia; Paola, Domingo

2003-01-01

This paper analyses a case study of a pair of students working together, who were asked to produce conjectures and to validate them within the dynamic geometry environment Cabri. Our aim is to scrutinize the students' reasoning, how the gap from perception to theory is filled, how Cabri influences the reasoning. We have singled out a sequence of…

Validation of the CORB75 (confusion, oxygen saturation, respiratory rate, blood pressure, and age ≥ 75 years) as a simpler pneumonia severity rule.

PubMed

Ochoa-Gondar, O; Vila-Corcoles, A; Rodriguez-Blanco, T; Hospital, I; Salsench, E; Ansa, X; Saun, N

2014-04-01

This study compares the ability of two simpler severity rules (classical CRB65 vs. proposed CORB75) in predicting short-term mortality in elderly patients with community-acquired pneumonia (CAP). A population-based study was undertaken involving 610 patients ≥ 65 years old with radiographically confirmed CAP diagnosed between 2008 and 2011 in Tarragona, Spain (350 cases in the derivation cohort, 260 cases in the validation cohort). Severity rules were calculated at the time of diagnosis, and 30-day mortality was considered as the dependent variable. The area under the receiver operating characteristic curves (AUC) was used to compare the discriminative power of the severity rules. Eighty deaths (46 in the derivation and 34 in the validation cohorts) were observed, which gives a mortality rate of 13.1 % (15.6 % for hospitalized and 3.3 % for outpatient cases). After multivariable analyses, besides CRB (confusion, respiration rate ≥ 30/min, systolic blood pressure <90 mmHg or diastolic ≤ 60 mmHg), peripheral oxygen saturation (≤ 90 %) and age ≥ 75 years appeared to be associated with increasing 30-day mortality in the derivation cohort. The model showed adequate calibration for the derivation and validation cohorts. A modified CORB75 scoring system (similar to the classical CRB65, but adding oxygen saturation and increasing the age to 75 years) was constructed. The AUC statistics for predicting mortality in the derivation and validation cohorts were 0.79 and 0.82, respectively. In the derivation cohort, a CORB75 score ≥ 2 showed 78.3 % sensitivity and 65.5 % specificity for mortality (in the validation cohort, these were 82.4 and 71.7 %, respectively). The proposed CORB75 scoring system has good discriminative power in predicting short-term mortality among elderly people with CAP, which supports its use for severity assessment of these patients in primary care.

Creation and Initial Validation of the International Dysphagia Diet Standardisation Initiative Functional Diet Scale

PubMed Central

Steele, Catriona M.; Namasivayam-MacDonald, Ashwini M.; Guida, Brittany T.; Cichero, Julie A.; Duivestein, Janice; MRSc; Hanson, Ben; Lam, Peter; Riquelme, Luis F.

2018-01-01

Objective To assess consensual validity, interrater reliability, and criterion validity of the International Dysphagia Diet Standardisation Initiative Functional Diet Scale, a new functional outcome scale intended to capture the severity of oropharyngeal dysphagia, as represented by the degree of diet texture restriction recommended for the patient. Design Participants assigned International Dysphagia Diet Standardisation Initiative Functional Diet Scale scores to 16 clinical cases. Consensual validity was measured against reference scores determined by an author reference panel. Interrater reliability was measured overall and across quartile subsets of the dataset. Criterion validity was evaluated versus Functional Oral Intake Scale (FOIS) scores assigned by survey respondents to the same case scenarios. Feedback was requested regarding ease and likelihood of use. Setting Web-based survey. Participants Respondents (NZ170) from 29 countries. Interventions Not applicable. Main Outcome Measures Consensual validity (percent agreement and Kendall t), criterion validity (Spearman rank correlation), and interrater reliability (Kendall concordance and intraclass coefficients). Results The International Dysphagia Diet Standardisation Initiative Functional Diet Scale showed strong consensual validity, criterion validity, and interrater reliability. Scenarios involving liquid-only diets, transition from nonoral feeding, or trial diet advances in therapy showed the poorest consensus, indicating a need for clear instructions on how to score these situations. The International Dysphagia Diet Standardisation Initiative Functional Diet Scale showed greater sensitivity than the FOIS to specific changes in diet. Most (>70%) respondents indicated enthusiasm for implementing the International Dysphagia Diet Standardisation Initiative Functional Diet Scale. Conclusions This initial validation study suggests that the International Dysphagia Diet Standardisation Initiative Functional Diet Scale has strong consensual and criterion validity and can be used reliably by clinicians to capture diet texture restriction and progression in people with dysphagia. PMID:29428348

Creation and Initial Validation of the International Dysphagia Diet Standardisation Initiative Functional Diet Scale.

PubMed

Steele, Catriona M; Namasivayam-MacDonald, Ashwini M; Guida, Brittany T; Cichero, Julie A; Duivestein, Janice; Hanson, Ben; Lam, Peter; Riquelme, Luis F

2018-05-01

To assess consensual validity, interrater reliability, and criterion validity of the International Dysphagia Diet Standardisation Initiative Functional Diet Scale, a new functional outcome scale intended to capture the severity of oropharyngeal dysphagia, as represented by the degree of diet texture restriction recommended for the patient. Participants assigned International Dysphagia Diet Standardisation Initiative Functional Diet Scale scores to 16 clinical cases. Consensual validity was measured against reference scores determined by an author reference panel. Interrater reliability was measured overall and across quartile subsets of the dataset. Criterion validity was evaluated versus Functional Oral Intake Scale (FOIS) scores assigned by survey respondents to the same case scenarios. Feedback was requested regarding ease and likelihood of use. Web-based survey. Respondents (N=170) from 29 countries. Not applicable. Consensual validity (percent agreement and Kendall τ), criterion validity (Spearman rank correlation), and interrater reliability (Kendall concordance and intraclass coefficients). The International Dysphagia Diet Standardisation Initiative Functional Diet Scale showed strong consensual validity, criterion validity, and interrater reliability. Scenarios involving liquid-only diets, transition from nonoral feeding, or trial diet advances in therapy showed the poorest consensus, indicating a need for clear instructions on how to score these situations. The International Dysphagia Diet Standardisation Initiative Functional Diet Scale showed greater sensitivity than the FOIS to specific changes in diet. Most (>70%) respondents indicated enthusiasm for implementing the International Dysphagia Diet Standardisation Initiative Functional Diet Scale. This initial validation study suggests that the International Dysphagia Diet Standardisation Initiative Functional Diet Scale has strong consensual and criterion validity and can be used reliably by clinicians to capture diet texture restriction and progression in people with dysphagia. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Designing and validation of a yoga-based intervention for schizophrenia.

PubMed

Govindaraj, Ramajayam; Varambally, Shivarama; Sharma, Manjunath; Gangadhar, Bangalore Nanjundaiah

2016-06-01

Schizophrenia is a chronic mental illness which causes significant distress and dysfunction. Yoga has been found to be effective as an add-on therapy in schizophrenia. Modules of yoga used in previous studies were based on individual researcher's experience. This study aimed to develop and validate a specific generic yoga-based intervention module for patients with schizophrenia. The study was conducted at NIMHANS Integrated Centre for Yoga (NICY). A yoga module was designed based on traditional and contemporary yoga literature as well as published studies. The yoga module along with three case vignettes of adult patients with schizophrenia was sent to 10 yoga experts for their validation. Experts (n = 10) gave their opinion on the usefulness of a yoga module for patients with schizophrenia with some modifications. In total, 87% (13 of 15 items) of the items in the initial module were retained, with modification in the remainder as suggested by the experts. A specific yoga-based module for schizophrenia was designed and validated by experts. Further studies are needed to confirm efficacy and clinical utility of the module. Additional clinical validation is suggested.

Assessing Competence in Collaborative Case Conceptualization: Development and Preliminary Psychometric Properties of the Collaborative Case Conceptualization Rating Scale (CCC-RS).

PubMed

Kuyken, Willem; Beshai, Shadi; Dudley, Robert; Abel, Anna; Görg, Nora; Gower, Philip; McManus, Freda; Padesky, Christine A

2016-03-01

Case conceptualization is assumed to be an important element in cognitive-behavioural therapy (CBT) because it describes and explains clients' presentations in ways that inform intervention. However, we do not have a good measure of competence in CBT case conceptualization that can be used to guide training and elucidate mechanisms. The current study addresses this gap by describing the development and preliminary psychometric properties of the Collaborative Case Conceptualization - Rating Scale (CCC-RS; Padesky et al., 2011). The CCC-RS was developed in accordance with the model posited by Kuyken et al. (2009). Data for this study (N = 40) were derived from a larger trial (Wiles et al., 2013) with adults suffering from resistant depression. Internal consistency and inter-rater reliability were calculated. Further, and as a partial test of the scale's validity, Pearson's correlation coefficients were obtained for scores on the CCC-RS and key scales from the Cognitive Therapy Scale - Revised (CTS-R; Blackburn et al., 2001). The CCC-RS showed excellent internal consistency (α = .94), split-half (.82) and inter-rater reliabilities (ICC =.84). Total scores on the CCC-RS were significantly correlated with scores on the CTS-R (r = .54, p < .01). Moreover, the Collaboration subscale of the CCC-RS was significantly correlated (r = .44) with its counterpart of the CTS-R in a theoretically predictable manner. These preliminary results indicate that the CCC-RS is a reliable measure with adequate face, content and convergent validity. Further research is needed to replicate and extend the current findings to other facets of validity.

Validity of the coding for herpes simplex encephalitis in the Danish National Patient Registry.

PubMed

Jørgensen, Laura Krogh; Dalgaard, Lars Skov; Østergaard, Lars Jørgen; Andersen, Nanna Skaarup; Nørgaard, Mette; Mogensen, Trine Hyrup

2016-01-01

Large health care databases are a valuable source of infectious disease epidemiology if diagnoses are valid. The aim of this study was to investigate the accuracy of the recorded diagnosis coding of herpes simplex encephalitis (HSE) in the Danish National Patient Registry (DNPR). The DNPR was used to identify all hospitalized patients, aged ≥15 years, with a first-time diagnosis of HSE according to the International Classification of Diseases, tenth revision (ICD-10), from 2004 to 2014. To validate the coding of HSE, we collected data from the Danish Microbiology Database, from departments of clinical microbiology, and from patient medical records. Cases were classified as confirmed, probable, or no evidence of HSE. We estimated the positive predictive value (PPV) of the HSE diagnosis coding stratified by diagnosis type, study period, and department type. Furthermore, we estimated the proportion of HSE cases coded with nonspecific ICD-10 codes of viral encephalitis and also the sensitivity of the HSE diagnosis coding. We were able to validate 398 (94.3%) of the 422 HSE diagnoses identified via the DNPR. Hereof, 202 (50.8%) were classified as confirmed cases and 29 (7.3%) as probable cases providing an overall PPV of 58.0% (95% confidence interval [CI]: 53.0-62.9). For "Encephalitis due to herpes simplex virus" (ICD-10 code B00.4), the PPV was 56.6% (95% CI: 51.1-62.0). Similarly, the PPV for "Meningoencephalitis due to herpes simplex virus" (ICD-10 code B00.4A) was 56.8% (95% CI: 39.5-72.9). "Herpes viral encephalitis" (ICD-10 code G05.1E) had a PPV of 75.9% (95% CI: 56.5-89.7), thereby representing the highest PPV. The estimated sensitivity was 95.5%. The PPVs of the ICD-10 diagnosis coding for adult HSE in the DNPR were relatively low. Hence, the DNPR should be used with caution when studying patients with encephalitis caused by herpes simplex virus.

International genome-wide meta-analysis identifies new primary biliary cirrhosis risk loci and targetable pathogenic pathways.

PubMed

Cordell, Heather J; Han, Younghun; Mells, George F; Li, Yafang; Hirschfield, Gideon M; Greene, Casey S; Xie, Gang; Juran, Brian D; Zhu, Dakai; Qian, David C; Floyd, James A B; Morley, Katherine I; Prati, Daniele; Lleo, Ana; Cusi, Daniele; Gershwin, M Eric; Anderson, Carl A; Lazaridis, Konstantinos N; Invernizzi, Pietro; Seldin, Michael F; Sandford, Richard N; Amos, Christopher I; Siminovitch, Katherine A

2015-09-22

Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 × 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist.

Scrutinizing A Survey-Based Measure of Science and Mathematics Teacher Knowledge: Relationship to Observations of Teaching Practice

ERIC Educational Resources Information Center

Talbot, Robert M., III

2017-01-01

There is a clear need for valid and reliable instrumentation that measures teacher knowledge. However, the process of investigating and making a case for instrument validity is not a simple undertaking; rather, it is a complex endeavor. This paper presents the empirical case of one aspect of such an instrument validation effort. The particular…

A risk-model for hospital mortality among patients with severe sepsis or septic shock based on German national administrative claims data

PubMed Central

Fleischmann-Struzek, Carolin; Rüddel, Hendrik; Reinhart, Konrad; Thomas-Rüddel, Daniel O.

2018-01-01

Background Sepsis is a major cause of preventable deaths in hospitals. Feasible and valid methods for comparing quality of sepsis care between hospitals are needed. The aim of this study was to develop a risk-adjustment model suitable for comparing sepsis-related mortality between German hospitals. Methods We developed a risk-model using national German claims data. Since these data are available with a time-lag of 1.5 years only, the stability of the model across time was investigated. The model was derived from inpatient cases with severe sepsis or septic shock treated in 2013 using logistic regression with backward selection and generalized estimating equations to correct for clustering. It was validated among cases treated in 2015. Finally, the model development was repeated in 2015. To investigate secular changes, the risk-adjusted trajectory of mortality across the years 2010–2015 was analyzed. Results The 2013 deviation sample consisted of 113,750 cases; the 2015 validation sample consisted of 134,851 cases. The model developed in 2013 showed good validity regarding discrimination (AUC = 0.74), calibration (observed mortality in 1st and 10th risk-decile: 11%-78%), and fit (R2 = 0.16). Validity remained stable when the model was applied to 2015 (AUC = 0.74, 1st and 10th risk-decile: 10%-77%, R2 = 0.17). There was no indication of overfitting of the model. The final model developed in year 2015 contained 40 risk-factors. Between 2010 and 2015 hospital mortality in sepsis decreased from 48% to 42%. Adjusted for risk-factors the trajectory of decrease was still significant. Conclusions The risk-model shows good predictive validity and stability across time. The model is suitable to be used as an external algorithm for comparing risk-adjusted sepsis mortality among German hospitals or regions based on administrative claims data, but secular changes need to be taken into account when interpreting risk-adjusted mortality. PMID:29558486

A risk-model for hospital mortality among patients with severe sepsis or septic shock based on German national administrative claims data.

PubMed

Schwarzkopf, Daniel; Fleischmann-Struzek, Carolin; Rüddel, Hendrik; Reinhart, Konrad; Thomas-Rüddel, Daniel O

2018-01-01

Sepsis is a major cause of preventable deaths in hospitals. Feasible and valid methods for comparing quality of sepsis care between hospitals are needed. The aim of this study was to develop a risk-adjustment model suitable for comparing sepsis-related mortality between German hospitals. We developed a risk-model using national German claims data. Since these data are available with a time-lag of 1.5 years only, the stability of the model across time was investigated. The model was derived from inpatient cases with severe sepsis or septic shock treated in 2013 using logistic regression with backward selection and generalized estimating equations to correct for clustering. It was validated among cases treated in 2015. Finally, the model development was repeated in 2015. To investigate secular changes, the risk-adjusted trajectory of mortality across the years 2010-2015 was analyzed. The 2013 deviation sample consisted of 113,750 cases; the 2015 validation sample consisted of 134,851 cases. The model developed in 2013 showed good validity regarding discrimination (AUC = 0.74), calibration (observed mortality in 1st and 10th risk-decile: 11%-78%), and fit (R2 = 0.16). Validity remained stable when the model was applied to 2015 (AUC = 0.74, 1st and 10th risk-decile: 10%-77%, R2 = 0.17). There was no indication of overfitting of the model. The final model developed in year 2015 contained 40 risk-factors. Between 2010 and 2015 hospital mortality in sepsis decreased from 48% to 42%. Adjusted for risk-factors the trajectory of decrease was still significant. The risk-model shows good predictive validity and stability across time. The model is suitable to be used as an external algorithm for comparing risk-adjusted sepsis mortality among German hospitals or regions based on administrative claims data, but secular changes need to be taken into account when interpreting risk-adjusted mortality.

Development, Sensibility, and Validity of a Systemic Autoimmune Rheumatic Disease Case Ascertainment Tool.

PubMed

Armstrong, Susan M; Wither, Joan E; Borowoy, Alan M; Landolt-Marticorena, Carolina; Davis, Aileen M; Johnson, Sindhu R

2017-01-01

Case ascertainment through self-report is a convenient but often inaccurate method to collect information. The purposes of this study were to develop, assess the sensibility, and validate a tool to identify cases of systemic autoimmune rheumatic diseases (SARD) in the outpatient setting. The SARD tool was administered to subjects sampled from specialty clinics. Determinants of sensibility - comprehensibility, feasibility, validity, and acceptability - were evaluated using a numeric rating scale from 1-7. Comprehensibility was evaluated using the Flesch Reading Ease and the Flesch-Kincaid Grade Level. Self-reported diagnoses were validated against medical records using Cohen's κ statistic. There were 141 participants [systemic lupus erythematosus (SLE), systemic sclerosis (SSc), rheumatoid arthritis, Sjögren syndrome (SS), inflammatory myositis (polymyositis/dermatomyositis; PM/DM), and controls] who completed the questionnaire. The Flesch Reading Ease score was 77.1 and the Flesch-Kincaid Grade Level was 4.4. Respondents endorsed (mean ± SD) comprehensibility (6.12 ± 0.92), feasibility (5.94 ± 0.81), validity (5.35 ± 1.10), and acceptability (3.10 ± 2.03). The SARD tool had a sensitivity of 0.91 (95% CI 0.88-0.94) and a specificity of 0.99 (95% CI 0.96-1.00). The agreement between the SARD tool and medical record was κ = 0.82 (95% CI 0.77-0.88). Subgroup analysis by SARD found κ coefficients for SLE to be κ = 0.88 (95% CI 0.79-0.97), SSc κ = 1.0 (95% CI 1.0-1.0), PM/DM κ = 0.72 (95% CI 0.49-0.95), and SS κ = 0.85 (95% CI 0.71-0.99). The screening questions had sensitivity ranging from 0.96 to 1.0 and specificity ranging from 0.88 to 1.0. This SARD case ascertainment tool has demonstrable sensibility and validity. The use of both screening and confirmatory questions confers added accuracy.

Optimal control model predictions of system performance and attention allocation and their experimental validation in a display design study

NASA Technical Reports Server (NTRS)

Johannsen, G.; Govindaraj, T.

1980-01-01

The influence of different types of predictor displays in a longitudinal vertical takeoff and landing (VTOL) hover task is analyzed in a theoretical study. Several cases with differing amounts of predictive and rate information are compared. The optimal control model of the human operator is used to estimate human and system performance in terms of root-mean-square (rms) values and to compute optimized attention allocation. The only part of the model which is varied to predict these data is the observation matrix. Typical cases are selected for a subsequent experimental validation. The rms values as well as eye-movement data are recorded. The results agree favorably with those of the theoretical study in terms of relative differences. Better matching is achieved by revised model input data.

School Asthma Screening and Case Management: Attendance and Learning Outcomes

ERIC Educational Resources Information Center

Moricca, Michelle L.; Grasska, Merry A.; BMarthaler, Marcia; Morphew, Tricia; Weismuller, Penny C.; Galant, Stanley P.

2013-01-01

Asthma is related to school absenteeism and underperformance in elementary students. This pilot study assessed whether school nurse case management (CM) in children identified with asthma impacts academic performance and school absenteeism in one school. A validated questionnaire was used to identify children at risk for asthma and CM was provided…

What Works Clearinghouse Standards and Generalization of Single-Case Design Evidence

ERIC Educational Resources Information Center

Hitchcock, John H.; Kratochwill, Thomas R.; Chezan, Laura C.

2015-01-01

A recent review of existing rubrics designed to help researchers evaluate the internal and external validity of single-case design (SCD) studies found that the various options yield consistent results when examining causal arguments. The authors of the review, however, noted considerable differences across the rubrics when addressing the…

The Reliability and Validity of the Thoracolumbar Injury Classification System in Pediatric Spine Trauma.

PubMed

Savage, Jason W; Moore, Timothy A; Arnold, Paul M; Thakur, Nikhil; Hsu, Wellington K; Patel, Alpesh A; McCarthy, Kathryn; Schroeder, Gregory D; Vaccaro, Alexander R; Dimar, John R; Anderson, Paul A

2015-09-15

The thoracolumbar injury classification system (TLICS) was evaluated in 20 consecutive pediatric spine trauma cases. The purpose of this study was to determine the reliability and validity of the TLICS in pediatric spine trauma. The TLICS was developed to improve the categorization and management of thoracolumbar trauma. TLICS has been shown to have good reliability and validity in the adult population. The clinical and radiographical findings of 20 pediatric thoracolumbar fractures were prospectively presented to 20 surgeons with disparate levels of training and experience with spinal trauma. These injuries were consecutively scored using the TLICS. Cohen unweighted κ coefficients and Spearman rank order correlation values were calculated for the key parameters (injury morphology, status of posterior ligamentous complex, neurological status, TLICS total score, and proposed management) to assess the inter-rater reliabilities. Five surgeons scored the same cases 3 months later to assess the intra-rater reliability. The actual management of each case was then compared with the treatment recommended by the TLICS algorithm to assess validity. The inter-rater κ statistics of all subgroups (injury morphology, status of the posterior ligamentous complex, neurological status, TLICS total score, and proposed treatment) were within the range of moderate to substantial reproducibility (0.524-0.958). All subgroups had excellent intra-rater reliability (0.748-1.000). The various indices for validity were calculated (80.3% correct, 0.836 sensitivity, 0.785 specificity, 0.676 positive predictive value, 0.899 negative predictive value). Overall, TLICS demonstrated good validity. The TLICS has good reliability and validity when used in the pediatric population. The inter-rater reliability of predicting management and indices for validity are lower than those in adults with thoracolumbar fractures, which is likely due to differences in the way children are treated for certain types of injuries. TLICS can be used to reliably categorize thoracolumbar injuries in the pediatric population; however, modifications may be needed to better guide treatment in this specific patient population. 4.

Systematic review of validated case definitions for diabetes in ICD-9-coded and ICD-10-coded data in adult populations.

PubMed

Khokhar, Bushra; Jette, Nathalie; Metcalfe, Amy; Cunningham, Ceara Tess; Quan, Hude; Kaplan, Gilaad G; Butalia, Sonia; Rabi, Doreen

2016-08-05

With steady increases in 'big data' and data analytics over the past two decades, administrative health databases have become more accessible and are now used regularly for diabetes surveillance. The objective of this study is to systematically review validated International Classification of Diseases (ICD)-based case definitions for diabetes in the adult population. Electronic databases, MEDLINE and Embase, were searched for validation studies where an administrative case definition (using ICD codes) for diabetes in adults was validated against a reference and statistical measures of the performance reported. The search yielded 2895 abstracts, and of the 193 potentially relevant studies, 16 met criteria. Diabetes definition for adults varied by data source, including physician claims (sensitivity ranged from 26.9% to 97%, specificity ranged from 94.3% to 99.4%, positive predictive value (PPV) ranged from 71.4% to 96.2%, negative predictive value (NPV) ranged from 95% to 99.6% and κ ranged from 0.8 to 0.9), hospital discharge data (sensitivity ranged from 59.1% to 92.6%, specificity ranged from 95.5% to 99%, PPV ranged from 62.5% to 96%, NPV ranged from 90.8% to 99% and κ ranged from 0.6 to 0.9) and a combination of both (sensitivity ranged from 57% to 95.6%, specificity ranged from 88% to 98.5%, PPV ranged from 54% to 80%, NPV ranged from 98% to 99.6% and κ ranged from 0.7 to 0.8). Overall, administrative health databases are useful for undertaking diabetes surveillance, but an awareness of the variation in performance being affected by case definition is essential. The performance characteristics of these case definitions depend on the variations in the definition of primary diagnosis in ICD-coded discharge data and/or the methodology adopted by the healthcare facility to extract information from patient records. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Studying the neurobiology of human social interaction: Making the case for ecological validity.

PubMed

Hogenelst, Koen; Schoevers, Robert A; aan het Rot, Marije

2015-01-01

With this commentary we make the case for an increased focus on the ecological validity of the measures used to assess aspects of human social functioning. Impairments in social functioning are seen in many types of psychopathology, negatively affecting the lives of psychiatric patients and those around them. Yet the neurobiology underlying abnormal social interaction remains unclear. As an example of human social neuroscience research with relevance to biological psychiatry and clinical psychopharmacology, this commentary discusses published experimental studies involving manipulation of the human brain serotonin system that included assessments of social behavior. To date, these studies have mostly been laboratory-based and included computer tasks, observations by others, or single-administration self-report measures. Most laboratory measures used so far inform about the role of serotonin in aspects of social interaction, but the relevance for real-life interaction is often unclear. Few studies have used naturalistic assessments in real life. We suggest several laboratory methods with high ecological validity as well as ecological momentary assessment, which involves intensive repeated measures in naturalistic settings. In sum, this commentary intends to stimulate experimental research on the neurobiology of human social interaction as it occurs in real life.

French Validation of the Multidimensional Attitude Scale toward Persons with Disabilities (MAS): The Case of Attitudes toward Autism and Their Moderating Factors

ERIC Educational Resources Information Center

Dachez, Julie; Ndobo, Andre; Ameline, Anaïs

2015-01-01

This research investigates the renewed interest in autism, the stigmatization of persons with autism and the need to better measure such stigmatization. Two studies were thus conducted on 101 and 104 participants in order to validate the French version of the Multidimensional Attitude Scale toward persons with disabilities, and examine the…

Developing Instruments to Assess and Compare the Quality of Engineering Education: The Case of China and Russia

ERIC Educational Resources Information Center

Kardanova, Elena; Loyalka, Prashant; Chirikov, Igor; Liu, Lydia; Li, Guirong; Wang, Huan; Enchikova, Ekaterina; Shi, Henry; Johnson, Natalie

2016-01-01

Relatively little is known about differences in the quality of engineering education within and across countries because of the lack of valid instruments that allow for the assessment and comparison of engineering students' skill gains. The purpose of our study is to develop and validate instruments that can be used to compare student skill gains…

Challenging evidence-based decision-making: a hypothetical case study about return to work.

PubMed

Aas, Randi W; Alexanderson, Kristina

2012-03-01

A hypothetical case study about return to work was used to explore the process of translating research into practice. The method involved constructing a case study derived from the characteristics of a typical, sick-listed employee with non-specific low back pain in Norway. Next, the five-step evidence-based process, including the Patient, Intervention, Co-Interventions and Outcome framework (PICO), was applied to the case study. An inductive analysis produced 10 technical and more fundamental challenges to incorporate research into intervention decisions for an individual with comorbidity. A more dynamic, interactive approach to the evidence-based practice process is proposed. It is recommended that this plus the 10 challenges are validated with real life cases, as the hypothetical case study may not be replicable. Copyright © 2011 John Wiley & Sons, Ltd.

Validating Remotely Sensed Land Surface Evapotranspiration Based on Multi-scale Field Measurements

NASA Astrophysics Data System (ADS)

Jia, Z.; Liu, S.; Ziwei, X.; Liang, S.

2012-12-01

The land surface evapotranspiration plays an important role in the surface energy balance and the water cycle. There have been significant technical and theoretical advances in our knowledge of evapotranspiration over the past two decades. Acquisition of the temporally and spatially continuous distribution of evapotranspiration using remote sensing technology has attracted the widespread attention of researchers and managers. However, remote sensing technology still has many uncertainties coming from model mechanism, model inputs, parameterization schemes, and scaling issue in the regional estimation. Achieving remotely sensed evapotranspiration (RS_ET) with confident certainty is required but difficult. As a result, it is indispensable to develop the validation methods to quantitatively assess the accuracy and error sources of the regional RS_ET estimations. This study proposes an innovative validation method based on multi-scale evapotranspiration acquired from field measurements, with the validation results including the accuracy assessment, error source analysis, and uncertainty analysis of the validation process. It is a potentially useful approach to evaluate the accuracy and analyze the spatio-temporal properties of RS_ET at both the basin and local scales, and is appropriate to validate RS_ET in diverse resolutions at different time-scales. An independent RS_ET validation using this method was presented over the Hai River Basin, China in 2002-2009 as a case study. Validation at the basin scale showed good agreements between the 1 km annual RS_ET and the validation data such as the water balanced evapotranspiration, MODIS evapotranspiration products, precipitation, and landuse types. Validation at the local scale also had good results for monthly, daily RS_ET at 30 m and 1 km resolutions, comparing to the multi-scale evapotranspiration measurements from the EC and LAS, respectively, with the footprint model over three typical landscapes. Although some validation experiments demonstrated that the models yield accurate estimates at flux measurement sites, the question remains whether they are performing well over the broader landscape. Moreover, a large number of RS_ET products have been released in recent years. Thus, we also pay attention to the cross-validation method of RS_ET derived from multi-source models. "The Multi-scale Observation Experiment on Evapotranspiration over Heterogeneous Land Surfaces: Flux Observation Matrix" campaign is carried out at the middle reaches of the Heihe River Basin, China in 2012. Flux measurements from an observation matrix composed of 22 EC and 4 LAS are acquired to investigate the cross-validation of multi-source models over different landscapes. In this case, six remote sensing models, including the empirical statistical model, the one-source and two-source models, the Penman-Monteith equation based model, the Priestley-Taylor equation based model, and the complementary relationship based model, are used to perform an intercomparison. All the results from the two cases of RS_ET validation showed that the proposed validation methods are reasonable and feasible.

Social validity in single-case research: A systematic literature review of prevalence and application.

PubMed

Snodgrass, Melinda R; Chung, Moon Y; Meadan, Hedda; Halle, James W

2018-03-01

Single-case research (SCR) has been a valuable methodology in special education research. Montrose Wolf (1978), an early pioneer in single-case methodology, coined the term "social validity" to refer to the social importance of the goals selected, the acceptability of procedures employed, and the effectiveness of the outcomes produced in applied investigations. Since 1978, many contributors to SCR have included social validity as a feature of their articles and several authors have examined the prevalence and role of social validity in SCR. We systematically reviewed all SCR published in six highly-ranked special education journals from 2005 to 2016 to establish the prevalence of social validity assessments and to evaluate their scientific rigor. We found relatively low, but stable prevalence with only 28 publications addressing all three factors of the social validity construct (i.e., goals, procedures, outcomes). We conducted an in-depth analysis of the scientific rigor of these 28 publications. Social validity remains an understudied construct in SCR, and the scientific rigor of social validity assessments is often lacking. Implications and future directions are discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Single case studies as a means for developing psychological theories.

PubMed

Skvortsov, Anatoliy; Romashchuk, Alexander

2015-12-01

The Socratic function of single case studies (SCSs) is described in its relation to the problem of scientific theory development. Contrary to the traditional point of view, the single case study is not a demonstration or verification of theoretical concepts, but a method of their generation and opportunity for analysis of their interrelations. Considering the case study from the perspective of the Socratic function brings to light important conclusions about the ecological validity of theory development. The essential features of the Socratic function are illustrated using the example of the famous Romantic Essays of Alexandr Luria. © 2015 The Institute of Psychology, Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

High wavenumber Raman spectroscopy in the characterization of urinary metabolites of normal subjects, oral premalignant and malignant patients

NASA Astrophysics Data System (ADS)

Brindha, Elumalai; Rajasekaran, Ramu; Aruna, Prakasarao; Koteeswaran, Dornadula; Ganesan, Singaravelu

2017-01-01

Urine has emerged as one of the diagnostically potential bio fluids, as it has many metabolites. As the concentration and the physiochemical properties of the urinary metabolites may vary under pathological transformation, Raman spectroscopic characterization of urine has been exploited as a significant tool in identifying several diseased conditions, including cancers. In the present study, an attempt was made to study the high wavenumber (HWVN) Raman spectroscopic characterization of urine samples of normal subjects, oral premalignant and malignant patients. It is concluded that the urinary metabolites flavoproteins, tryptophan and phenylalanine are responsible for the observed spectral variations between the normal and abnormal groups. Principal component analysis-based linear discriminant analysis was carried out to verify the diagnostic potentiality of the present technique. The discriminant analysis performed across normal and oral premalignant subjects classifies 95.6% of the original and 94.9% of the cross-validated grouped cases correctly. In the second analysis performed across normal and oral malignant groups, the accuracy of the original and cross-validated grouped cases was 96.4% and 92.1% respectively. Similarly, the third analysis performed across three groups, normal, oral premalignant and malignant groups, classifies 93.3% and 91.2% of the original and cross-validated grouped cases correctly.

Performance of Case-Based Reasoning Retrieval Using Classification Based on Associations versus Jcolibri and FreeCBR: A Further Validation Study

NASA Astrophysics Data System (ADS)

Aljuboori, Ahmed S.; Coenen, Frans; Nsaif, Mohammed; Parsons, David J.

2018-05-01

Case-Based Reasoning (CBR) plays a major role in expert system research. However, a critical problem can be met when a CBR system retrieves incorrect cases. Class Association Rules (CARs) have been utilized to offer a potential solution in a previous work. The aim of this paper was to perform further validation of Case-Based Reasoning using a Classification based on Association Rules (CBRAR) to enhance the performance of Similarity Based Retrieval (SBR). The CBRAR strategy uses a classed frequent pattern tree algorithm (FP-CAR) in order to disambiguate wrongly retrieved cases in CBR. The research reported in this paper makes contributions to both fields of CBR and Association Rules Mining (ARM) in that full target cases can be extracted from the FP-CAR algorithm without invoking P-trees and union operations. The dataset used in this paper provided more efficient results when the SBR retrieves unrelated answers. The accuracy of the proposed CBRAR system outperforms the results obtained by existing CBR tools such as Jcolibri and FreeCBR.

Approaches to ascertaining comorbidity information: validation of routine hospital episode data with clinician-based case note review.

PubMed

Soo, Martin; Robertson, Lynn M; Ali, Tariq; Clark, Laura E; Fluck, Nicholas; Johnston, Marjorie; Marks, Angharad; Prescott, Gordon J; Smith, William Cairns S; Black, Corri

2014-04-21

In clinical practice, research, and increasingly health surveillance, planning and costing, there is a need for high quality information to determine comorbidity information about patients. Electronic, routinely collected healthcare data is capturing increasing amounts of clinical information as part of routine care. The aim of this study was to assess the validity of routine hospital administrative data to determine comorbidity, as compared with clinician-based case note review, in a large cohort of patients with chronic kidney disease. A validation study using record linkage. Routine hospital administrative data were compared with clinician-based case note review comorbidity data in a cohort of 3219 patients with chronic kidney disease. To assess agreement, we calculated prevalence, kappa statistic, sensitivity, specificity, positive predictive value and negative predictive value. Subgroup analyses were also performed. Median age at index date was 76.3 years, 44% were male, 67% had stage 3 chronic kidney disease and 31% had at least three comorbidities. For most comorbidities, we found a higher prevalence recorded from case notes compared with administrative data. The best agreement was found for cerebrovascular disease (κ = 0.80) ischaemic heart disease (κ = 0.63) and diabetes (κ = 0.65). Hypertension, peripheral vascular disease and dementia showed only fair agreement (κ = 0.28, 0.39, 0.38 respectively) and smoking status was found to be poorly recorded in administrative data. The patterns of prevalence across subgroups were as expected and for most comorbidities, agreement between case note and administrative data was similar. Agreement was less, however, in older ages and for those with three or more comorbidities for some conditions. This study demonstrates that hospital administrative comorbidity data compared moderately well with case note review data for cerebrovascular disease, ischaemic heart disease and diabetes, however there was significant under-recording of some other comorbid conditions, and particularly common risk factors.

On the validity of the use of a localized approximation for helical beams. I. Formal aspects

NASA Astrophysics Data System (ADS)

Gouesbet, Gérard; André Ambrosio, Leonardo

2018-03-01

The description of an electromagnetic beam for use in light scattering theories may be carried out by using an expansion over vector spherical wave functions with expansion coefficients expressed in terms of Beam Shape Coefficients (BSCs). A celebrated method to evaluate these BSCs has been the use of localized approximations (with several existing variants). We recently established that the use of any existing localized approximation is of limited validity in the case of Bessel and Mathieu beams. In the present paper, we address a warning against the use of any existing localized approximation in the case of helical beams. More specifically, we demonstrate that a procedure used to validate any existing localized approximation fails in the case of helical beams. Numerical computations in a companion paper will confirm that existing localized approximations are of limited validity in the case of helical beams.

Adaptation and validation of a Spanish-language version of the Frontotemporal Dementia Rating Scale (FTD-FRS).

PubMed

Turró-Garriga, O; Hermoso Contreras, C; Olives Cladera, J; Mioshi, E; Pelegrín Valero, C; Olivera Pueyo, J; Garre-Olmo, J; Sánchez-Valle, R

2017-06-01

The Frontotemporal Dementia Rating Scale (FTD-FRS) is a tool designed to aid with clinical staging and assessment of the progression of frontotemporal dementia (FTD-FRS). Present a multicentre adaptation and validation study of a Spanish version of the FRS. The adapted version was created using 2 translation-back translation processes (English to Spanish, Spanish to English) and verified by the scale's original authors. We validated the adapted version in a sample of consecutive patients diagnosed with FTD. The procedure included evaluating internal consistency, testing unidimensionality with the Rasch model, analysing construct validity and discriminant validity, and calculating the degree of agreement between the Clinical Dementia Rating scale (CDR) and FTD-FRS for FTD cases. The study included 60 patients with DFT. The mean score on the FRS was 12.1 points (SD=6.5; range, 2-25) with inter-group differences (F=120.3; df=3; P<.001). Cronbach's alpha was 0.897 and principal component analysis of residuals delivered an acceptable eigenvalue for 5 contrasts (1.6-2.7) and 36.1% raw variance. FRS was correlated with the Mini-mental State Examination (r=0.572; P<.001) and functional capacity (DAD; r=0.790; P<.001). FTD-FRS also showed a significant correlation with CDR (r=-0.641; P<.001), but we did observe variability in the severity levels; cases appeared to be less severe according to the CDR than when measured with the FTD-FRS (kappa=0.055). This process of validating the Spanish translation of the FTD-FRS yielded satisfactory results for validity and unidimensionality (severity) in the assessment of patients with FTD. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

DSMC Simulations of Hypersonic Flows and Comparison With Experiments

NASA Technical Reports Server (NTRS)

Moss, James N.; Bird, Graeme A.; Markelov, Gennady N.

2004-01-01

This paper presents computational results obtained with the direct simulation Monte Carlo (DSMC) method for several biconic test cases in which shock interactions and flow separation-reattachment are key features of the flow. Recent ground-based experiments have been performed for several biconic configurations, and surface heating rate and pressure measurements have been proposed for code validation studies. The present focus is to expand on the current validating activities for a relatively new DSMC code called DS2V that Bird (second author) has developed. Comparisons with experiments and other computations help clarify the agreement currently being achieved between computations and experiments and to identify the range of measurement variability of the proposed validation data when benchmarked with respect to the current computations. For the test cases with significant vibrational nonequilibrium, the effect of the vibrational energy surface accommodation on heating and other quantities is demonstrated.

Sterilization validation for medical devices at IRASM microbiological laboratory—Practical approaches

NASA Astrophysics Data System (ADS)

Trandafir, Laura; Alexandru, Mioara; Constantin, Mihai; Ioniţă, Anca; Zorilă, Florina; Moise, Valentin

2012-09-01

EN ISO 11137 established regulations for setting or substantiating the dose for achieving the desired sterility assurance level. The validation studies can be designed in particular for different types of products. Each product needs distinct protocols for bioburden determination and sterility testing. The Microbiological Laboratory from Irradiation Processing Center (IRASM) deals with different types of products, mainly for the VDmax25 method. When it comes to microbiological evaluation the most challenging was cotton gauze. A special situation for establishing the sterilization validation method appears in cases of cotton packed in large quantities. The VDmax25 method cannot be applied for items with average bioburden more than 1000 CFU/pack, irrespective of the weight of the package. This is a method limitation and implies increased costs for the manufacturer when choosing other methods. For microbiological tests, culture condition should be selected in both cases of the bioburden and sterility testing. Details about choosing criteria are given.

Validity of breast, lung and colorectal cancer diagnoses in administrative databases: a systematic review protocol.

PubMed

Abraha, Iosief; Giovannini, Gianni; Serraino, Diego; Fusco, Mario; Montedori, Alessandro

2016-03-18

Breast, lung and colorectal cancers constitute the most common cancers worldwide and their epidemiology, related health outcomes and quality indicators can be studied using administrative healthcare databases. To constitute a reliable source for research, administrative healthcare databases need to be validated. The aim of this protocol is to perform the first systematic review of studies reporting the validation of International Classification of Diseases 9th and 10th revision codes to identify breast, lung and colorectal cancer diagnoses in administrative healthcare databases. This review protocol has been developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocol (PRISMA-P) 2015 statement. We will search the following databases: MEDLINE, EMBASE, Web of Science and the Cochrane Library, using appropriate search strategies. We will include validation studies that used administrative data to identify breast, lung and colorectal cancer diagnoses or studies that evaluated the validity of breast, lung and colorectal cancer codes in administrative data. The following inclusion criteria will be used: (1) the presence of a reference standard case definition for the disease of interest; (2) the presence of at least one test measure (eg, sensitivity, positive predictive values, etc) and (3) the use of data source from an administrative database. Pairs of reviewers will independently abstract data using standardised forms and will assess quality using a checklist based on the Standards for Reporting of Diagnostic accuracy (STARD) criteria. Ethics approval is not required. We will submit results of this study to a peer-reviewed journal for publication. The results will serve as a guide to identify appropriate case definitions and algorithms of breast, lung and colorectal cancers for researchers involved in validating administrative healthcare databases as well as for outcome research on these conditions that used administrative healthcare databases. CRD42015026881. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

38 CFR 1.17 - Evaluation of studies relating to health effects of radiation exposure.

Code of Federal Regulations, 2012 CFR

2012-07-01

... health effects of radiation exposure. (a) From time to time, the Secretary shall publish evaluations of... paragraph a valid study is one which: (i) Has adequately described the study design and methods of data... studies affecting epidemiological assessments including case series, correlational studies and studies...

38 CFR 1.17 - Evaluation of studies relating to health effects of radiation exposure.

Code of Federal Regulations, 2013 CFR

2013-07-01

... health effects of radiation exposure. (a) From time to time, the Secretary shall publish evaluations of... paragraph a valid study is one which: (i) Has adequately described the study design and methods of data... studies affecting epidemiological assessments including case series, correlational studies and studies...

38 CFR 1.17 - Evaluation of studies relating to health effects of radiation exposure.

Code of Federal Regulations, 2014 CFR

2014-07-01

... health effects of radiation exposure. (a) From time to time, the Secretary shall publish evaluations of... paragraph a valid study is one which: (i) Has adequately described the study design and methods of data... studies affecting epidemiological assessments including case series, correlational studies and studies...

38 CFR 1.17 - Evaluation of studies relating to health effects of radiation exposure.

Code of Federal Regulations, 2010 CFR

2010-07-01

... health effects of radiation exposure. (a) From time to time, the Secretary shall publish evaluations of... paragraph a valid study is one which: (i) Has adequately described the study design and methods of data... studies affecting epidemiological assessments including case series, correlational studies and studies...

38 CFR 1.17 - Evaluation of studies relating to health effects of radiation exposure.

Code of Federal Regulations, 2011 CFR

2011-07-01

... health effects of radiation exposure. (a) From time to time, the Secretary shall publish evaluations of... paragraph a valid study is one which: (i) Has adequately described the study design and methods of data... studies affecting epidemiological assessments including case series, correlational studies and studies...

Number of organ dysfunctions predicts mortality in emergency department patients with suspected infection: a multicenter validation study.

PubMed

Jessen, Marie K; Skibsted, Simon; Shapiro, Nathan I

2017-06-01

The aim of this study was to validate the association between number of organ dysfunctions and mortality in emergency department (ED) patients with suspected infection. This study was conducted at two medical care center EDs. The internal validation set was a prospective cohort study conducted in Boston, USA. The external validation set was a retrospective case-control study conducted in Aarhus, Denmark. The study included adult patients (>18 years) with clinically suspected infection. Laboratory results and clinical data were used to assess organ dysfunctions. Inhospital mortality was the outcome measure. Multivariate logistic regression was used to determine the independent mortality odds for number and types of organ dysfunctions. We enrolled 4952 (internal) and 483 (external) patients. The mortality rate significantly increased with increasing number of organ dysfunctions: internal validation: 0 organ dysfunctions: 0.5% mortality, 1: 3.6%, 2: 9.5%, 3: 17%, and 4 or more: 37%; external validation: 2.2, 6.7, 17, 41, and 57% mortality (both P<0.001 for trend). Age-adjusted and comorbidity-adjusted number of organ dysfunctions remained an independent predictor. The effect of specific types of organ dysfunction on mortality was most pronounced for hematologic [odds ratio (OR) 3.3 (95% confidence interval (CI) 2.0-5.4)], metabolic [OR 3.3 (95% CI 2.4-4.6); internal validation], and cardiovascular dysfunctions [OR 14 (95% CI 3.7-50); external validation]. The number of organ dysfunctions predicts sepsis mortality.

Validity threats: overcoming interference with proposed interpretations of assessment data.

PubMed

Downing, Steven M; Haladyna, Thomas M

2004-03-01

Factors that interfere with the ability to interpret assessment scores or ratings in the proposed manner threaten validity. To be interpreted in a meaningful manner, all assessments in medical education require sound, scientific evidence of validity. The purpose of this essay is to discuss 2 major threats to validity: construct under-representation (CU) and construct-irrelevant variance (CIV). Examples of each type of threat for written, performance and clinical performance examinations are provided. The CU threat to validity refers to undersampling the content domain. Using too few items, cases or clinical performance observations to adequately generalise to the domain represents CU. Variables that systematically (rather than randomly) interfere with the ability to meaningfully interpret scores or ratings represent CIV. Issues such as flawed test items written at inappropriate reading levels or statistically biased questions represent CIV in written tests. For performance examinations, such as standardised patient examinations, flawed cases or cases that are too difficult for student ability contribute CIV to the assessment. For clinical performance data, systematic rater error, such as halo or central tendency error, represents CIV. The term face validity is rejected as representative of any type of legitimate validity evidence, although the fact that the appearance of the assessment may be an important characteristic other than validity is acknowledged. There are multiple threats to validity in all types of assessment in medical education. Methods to eliminate or control validity threats are suggested.

Implementing the undergraduate mini-CEX: a tailored approach at Southampton University.

PubMed

Hill, Faith; Kendall, Kathleen; Galbraith, Kevin; Crossley, Jim

2009-04-01

The mini-clinical evaluation exercise (mini-CEX) is widely used in the UK to assess clinical competence, but there is little evidence regarding its implementation in the undergraduate setting. This study aimed to estimate the validity and reliability of the undergraduate mini-CEX and discuss the challenges involved in its implementation. A total of 3499 mini-CEX forms were completed. Validity was assessed by estimating associations between mini-CEX score and a number of external variables, examining the internal structure of the instrument, checking competency domain response rates and profiles against expectations, and by qualitative evaluation of stakeholder interviews. Reliability was evaluated by overall reliability coefficient (R), estimation of the standard error of measurement (SEM), and from stakeholders' perceptions. Variance component analysis examined the contribution of relevant factors to students' scores. Validity was threatened by various confounding variables, including: examiner status; case complexity; attachment specialty; patient gender, and case focus. Factor analysis suggested that competency domains reflect a single latent variable. Maximum reliability can be achieved by aggregating scores over 15 encounters (R = 0.73; 95% confidence interval [CI] +/- 0.28 based on a 6-point assessment scale). Examiner stringency contributed 29% of score variation and student attachment aptitude 13%. Stakeholder interviews revealed staff development needs but the majority perceived the mini-CEX as more reliable and valid than the previous long case. The mini-CEX has good overall utility for assessing aspects of the clinical encounter in an undergraduate setting. Strengths include fidelity, wide sampling, perceived validity, and formative observation and feedback. Reliability is limited by variable examiner stringency, and validity by confounding variables, but these should be viewed within the context of overall assessment strategies.

Reliable and valid assessment of point-of-care ultrasonography.

PubMed

Todsen, Tobias; Tolsgaard, Martin Grønnebæk; Olsen, Beth Härstedt; Henriksen, Birthe Merete; Hillingsø, Jens Georg; Konge, Lars; Jensen, Morten Lind; Ringsted, Charlotte

2015-02-01

To explore the reliability and validity of the Objective Structured Assessment of Ultrasound Skills (OSAUS) scale for point-of-care ultrasonography (POC US) performance. POC US is increasingly used by clinicians and is an essential part of the management of acute surgical conditions. However, the quality of performance is highly operator-dependent. Therefore, reliable and valid assessment of trainees' ultrasonography competence is needed to ensure patient safety. Twenty-four physicians, representing novices, intermediates, and experts in POC US, scanned 4 different surgical patient cases in a controlled set-up. All ultrasound examinations were video-recorded and assessed by 2 blinded radiologists using OSAUS. Reliability was examined using generalizability theory. Construct validity was examined by comparing performance scores between the groups and by correlating physicians' OSAUS scores with diagnostic accuracy. The generalizability coefficient was high (0.81) and a D-study demonstrated that 1 assessor and 5 cases would result in similar reliability. The construct validity of the OSAUS scale was supported by a significant difference in the mean scores between the novice group (17.0; SD 8.4) and the intermediate group (30.0; SD 10.1), P = 0.007, as well as between the intermediate group and the expert group (72.9; SD 4.4), P = 0.04, and by a high correlation between OSAUS scores and diagnostic accuracy (Spearman ρ correlation coefficient = 0.76; P < 0.001). This study demonstrates high reliability as well as evidence of construct validity of the OSAUS scale for assessment of POC US competence. Hence, the OSAUS scale may be suitable for both in-training as well as end-of-training assessment.

Financial decision-making abilities and financial exploitation in older African Americans: Preliminary validity evidence for the Lichtenberg Financial Decision Rating Scale (LFDRS).

PubMed

Lichtenberg, Peter A; Ficker, Lisa J; Rahman-Filipiak, Annalise

2016-01-01

This study examines preliminary evidence for the Lichtenberg Financial Decision Rating Scale (LFDRS), a new person-centered approach to assessing capacity to make financial decisions, and its relationship to self-reported cases of financial exploitation in 69 older African Americans. More than one third of individuals reporting financial exploitation also had questionable decisional abilities. Overall, decisional ability score and current decision total were significantly associated with cognitive screening test and financial ability scores, demonstrating good criterion validity. Study findings suggest that impaired decisional abilities may render older adults more vulnerable to financial exploitation, and that the LFDRS is a valid tool.

A Case Study for Probabilistic Methods Validation (MSFC Center Director's Discretionary Fund, Project No. 94-26)

NASA Technical Reports Server (NTRS)

Price J. M.; Ortega, R.

1998-01-01

Probabilistic method is not a universally accepted approach for the design and analysis of aerospace structures. The validity of this approach must be demonstrated to encourage its acceptance as it viable design and analysis tool to estimate structural reliability. The objective of this Study is to develop a well characterized finite population of similar aerospace structures that can be used to (1) validate probabilistic codes, (2) demonstrate the basic principles behind probabilistic methods, (3) formulate general guidelines for characterization of material drivers (such as elastic modulus) when limited data is available, and (4) investigate how the drivers affect the results of sensitivity analysis at the component/failure mode level.

A machine learning approach to triaging patients with chronic obstructive pulmonary disease

PubMed Central

Qirko, Klajdi; Smith, Ted; Corcoran, Ethan; Wysham, Nicholas G.; Bazaz, Gaurav; Kappel, George; Gerber, Anthony N.

2017-01-01

COPD patients are burdened with a daily risk of acute exacerbation and loss of control, which could be mitigated by effective, on-demand decision support tools. In this study, we present a machine learning-based strategy for early detection of exacerbations and subsequent triage. Our application uses physician opinion in a statistically and clinically comprehensive set of patient cases to train a supervised prediction algorithm. The accuracy of the model is assessed against a panel of physicians each triaging identical cases in a representative patient validation set. Our results show that algorithm accuracy and safety indicators surpass all individual pulmonologists in both identifying exacerbations and predicting the consensus triage in a 101 case validation set. The algorithm is also the top performer in sensitivity, specificity, and ppv when predicting a patient’s need for emergency care. PMID:29166411

Psychometric instrumentation: reliability and validity of instruments used for clinical practice, evidence-based practice projects and research studies.

PubMed

Mayo, Ann M

2015-01-01

It is important for CNSs and other APNs to consider the reliability and validity of instruments chosen for clinical practice, evidence-based practice projects, or research studies. Psychometric testing uses specific research methods to evaluate the amount of error associated with any particular instrument. Reliability estimates explain more about how well the instrument is designed, whereas validity estimates explain more about scores that are produced by the instrument. An instrument may be architecturally sound overall (reliable), but the same instrument may not be valid. For example, if a specific group does not understand certain well-constructed items, then the instrument does not produce valid scores when used with that group. Many instrument developers may conduct reliability testing only once, yet continue validity testing in different populations over many years. All CNSs should be advocating for the use of reliable instruments that produce valid results. Clinical nurse specialists may find themselves in situations where reliability and validity estimates for some instruments that are being utilized are unknown. In such cases, CNSs should engage key stakeholders to sponsor nursing researchers to pursue this most important work.

The Science Manager's Guide to Case Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Branch, Kristi M.; Peffers, Melissa S.; Ruegg, Rosalie T.

2001-09-24

This guide takes the science manager through the steps of planning, implementing, validating, communicating, and using case studies. It outlines the major methods of analysis, describing their relative merits and applicability while providing relevant examples and sources of additional information. Well-designed case studies can provide a combination of rich qualitative and quantitative information, offering valuable insights into the nature, outputs, and longer-term impacts of the research. An objective, systematic, and credible approach to the evaluation of U.S. Department of Energy Office of Science programs adds value to the research process and is the subject of this guide.

Validity of Criteria-Based Content Analysis (CBCA) at Trial in Free-Narrative Interviews

ERIC Educational Resources Information Center

Roma, Paolo; San Martini, Pietro; Sabatello, Ugo; Tatarelli, Roberto; Ferracuti, Stefano

2011-01-01

Objective: The reliability of child witness testimony in sexual abuse cases is often controversial, and few tools are available. Criteria-Based Content Analysis (CBCA) is a widely used instrument for evaluating psychological credibility in cases of suspected child sexual abuse. Only few studies have evaluated CBCA scores in children suspected of…

A Case for Item-Level Indexing: The Kenneth Burke Papers at The Pennsylvania State University

ERIC Educational Resources Information Center

Sabre, Jeannette Mercer; Hamburger, Susan

2008-01-01

In light of numerous discussions about whether to follow Mark Greene and Dennis Meissner's suggestions to process lightly and broadly, valid reasons remain for continuing traditional practices for many literary correspondence collections. In this case study, the authors use the Kenneth Burke Papers in the Special Collections Library, Pennsylvania…

Three-Level Analysis of Single-Case Experimental Data: Empirical Validation

ERIC Educational Resources Information Center

Moeyaert, Mariola; Ugille, Maaike; Ferron, John M.; Beretvas, S. Natasha; Van den Noortgate, Wim

2014-01-01

One approach for combining single-case data involves use of multilevel modeling. In this article, the authors use a Monte Carlo simulation study to inform applied researchers under which realistic conditions the three-level model is appropriate. The authors vary the value of the immediate treatment effect and the treatment's effect on the time…

An Analysis of Allegations of Sexual Abuse in a Multi-Victim Day-Care Center Case.

ERIC Educational Resources Information Center

Bybee, Deborah; Mowbray, Carol T.

1993-01-01

This study applied criteria from Statement Validity Analysis (SVA) protocols to aggregate record review data of alleged sexual abuse of over 100 children in a day-care center. The use of SVA criteria supported the veritability of allegations in this case, with the data analysis reflecting consistency, logical structure, and spontaneity of…

Can species distribution models really predict the expansion of invasive species?

PubMed

Barbet-Massin, Morgane; Rome, Quentin; Villemant, Claire; Courchamp, Franck

2018-01-01

Predictive studies are of paramount importance for biological invasions, one of the biggest threats for biodiversity. To help and better prioritize management strategies, species distribution models (SDMs) are often used to predict the potential invasive range of introduced species. Yet, SDMs have been regularly criticized, due to several strong limitations, such as violating the equilibrium assumption during the invasion process. Unfortunately, validation studies-with independent data-are too scarce to assess the predictive accuracy of SDMs in invasion biology. Yet, biological invasions allow to test SDMs usefulness, by retrospectively assessing whether they would have accurately predicted the latest ranges of invasion. Here, we assess the predictive accuracy of SDMs in predicting the expansion of invasive species. We used temporal occurrence data for the Asian hornet Vespa velutina nigrithorax, a species native to China that is invading Europe with a very fast rate. Specifically, we compared occurrence data from the last stage of invasion (independent validation points) to the climate suitability distribution predicted from models calibrated with data from the early stage of invasion. Despite the invasive species not being at equilibrium yet, the predicted climate suitability of validation points was high. SDMs can thus adequately predict the spread of V. v. nigrithorax, which appears to be-at least partially-climatically driven. In the case of V. v. nigrithorax, SDMs predictive accuracy was slightly but significantly better when models were calibrated with invasive data only, excluding native data. Although more validation studies for other invasion cases are needed to generalize our results, our findings are an important step towards validating the use of SDMs in invasion biology.

Does expert opinion match the operational definition of the Lupus Low Disease Activity State (LLDAS)? A case-based construct validity study.

PubMed

Golder, Vera; Huq, Molla; Franklyn, Kate; Calderone, Alicia; Lateef, Aisha; Lau, Chak Sing; Lee, Alfred Lok Hang; Navarra, Sandra Teresa V; Godfrey, Timothy; Oon, Shereen; Hoi, Alberta Yik Bun; Morand, Eric Francis; Nikpour, Mandana

2017-06-01

To evaluate the construct validity of the Lupus Low Disease Activity State (LLDAS), a treatment target in systemic lupus erythematosus (SLE). Fifty SLE case summaries based on real patients were prepared and assessed independently for meeting the operational definition of LLDAS. Fifty international rheumatologists with expertise in SLE, but with no prior involvement in the LLDAS project, responded to a survey in which they were asked to categorize the disease activity state of each case as remission, low, moderate, or high. Agreement between expert opinion and LLDAS was assessed using Cohen's kappa. Overall agreement between expert opinion and the operational definition of LLDAS was 77.96% (95% CI: 76.34-79.58%), with a Cohen's kappa of 0.57 (95% CI: 0.55-0.61). Of the cases (22 of 50) that fulfilled the operational definition of LLDAS, only 5.34% (59 of 22 × 50) of responses classified the cases as moderate/high activity. Of the cases that did not fulfill the operational definition of LLDAS (28 of 50), 35.14% (492 of 28 × 50) of responses classified the cases as remission/low activity. Common reasons for discordance were assignment to remission/low activity of cases with higher corticosteroid doses than defined in LLDAS (prednisolone ≤ 7.5mg) or with SLEDAI-2K >4 due to serological activity (high anti-dsDNA antibody and/or low complement). LLDAS has good construct validity with high overall agreement between the operational definition of LLDAS and expert opinion. Discordance of results suggests that the operational definition of LLDAS is more stringent than expert opinion at defining a low disease activity state. Copyright © 2017 Elsevier Inc. All rights reserved.

Advanced information processing system: Fault injection study and results

NASA Technical Reports Server (NTRS)

Burkhardt, Laura F.; Masotto, Thomas K.; Lala, Jaynarayan H.

1992-01-01

The objective of the AIPS program is to achieve a validated fault tolerant distributed computer system. The goals of the AIPS fault injection study were: (1) to present the fault injection study components addressing the AIPS validation objective; (2) to obtain feedback for fault removal from the design implementation; (3) to obtain statistical data regarding fault detection, isolation, and reconfiguration responses; and (4) to obtain data regarding the effects of faults on system performance. The parameters are described that must be varied to create a comprehensive set of fault injection tests, the subset of test cases selected, the test case measurements, and the test case execution. Both pin level hardware faults using a hardware fault injector and software injected memory mutations were used to test the system. An overview is provided of the hardware fault injector and the associated software used to carry out the experiments. Detailed specifications are given of fault and test results for the I/O Network and the AIPS Fault Tolerant Processor, respectively. The results are summarized and conclusions are given.

Ethical issues in engineering models: an operations researcher's reflections.

PubMed

Kleijnen, J

2011-09-01

This article starts with an overview of the author's personal involvement--as an Operations Research consultant--in several engineering case-studies that may raise ethical questions; e.g., case-studies on nuclear waste, water management, sustainable ecology, military tactics, and animal welfare. All these case studies employ computer simulation models. In general, models are meant to solve practical problems, which may have ethical implications for the various stakeholders; namely, the modelers, the clients, and the public at large. The article further presents an overview of codes of ethics in a variety of disciples. It discusses the role of mathematical models, focusing on the validation of these models' assumptions. Documentation of these model assumptions needs special attention. Some ethical norms and values may be quantified through the model's multiple performance measures, which might be optimized. The uncertainty about the validity of the model leads to risk or uncertainty analysis and to a search for robust models. Ethical questions may be pressing in military models, including war games. However, computer games and the related experimental economics may also provide a special tool to study ethical issues. Finally, the article briefly discusses whistleblowing. Its many references to publications and websites enable further study of ethical issues in modeling.

Validation of the da Vinci Surgical Skill Simulator across three surgical disciplines: A pilot study

PubMed Central

Alzahrani, Tarek; Haddad, Richard; Alkhayal, Abdullah; Delisle, Josée; Drudi, Laura; Gotlieb, Walter; Fraser, Shannon; Bergman, Simon; Bladou, Frank; Andonian, Sero; Anidjar, Maurice

2013-01-01

Objective: In this paper, we evaluate face, content and construct validity of the da Vinci Surgical Skills Simulator (dVSSS) across 3 surgical disciplines. Methods: In total, 48 participants from urology, gynecology and general surgery participated in the study as novices (0 robotic cases performed), intermediates (1–74) or experts (≥75). Each participant completed 9 tasks (Peg board level 2, match board level 2, needle targeting, ring and rail level 2, dots and needles level 1, suture sponge level 2, energy dissection level 1, ring walk level 3 and tubes). The Mimic Technologies software scored each task from 0 (worst) to 100 (best) using several predetermined metrics. Face and content validity were evaluated by a questionnaire administered after task completion. Wilcoxon test was used to perform pair wise comparisons. Results: The expert group comprised of 6 attending surgeons. The intermediate group included 4 attending surgeons, 3 fellows and 5 residents. The novices included 1 attending surgeon, 1 fellow, 13 residents, 13 medical students and 2 research assistants. The median number of robotic cases performed by experts and intermediates were 250 and 9, respectively. The median overall realistic score (face validity) was 8/10. Experts rated the usefulness of the simulator as a training tool for residents (content validity) as 8.5/10. For construct validity, experts outperformed novices in all 9 tasks (p < 0.05). Intermediates outperformed novices in 7 of 9 tasks (p < 0.05); there were no significant differences in the energy dissection and ring walk tasks. Finally, experts scored significantly better than intermediates in only 3 of 9 tasks (matchboard, dots and needles and energy dissection) (p < 0.05). Conclusions: This study confirms the face, content and construct validities of the dVSSS across urology, gynecology and general surgery. Larger sample size and more complex tasks are needed to further differentiate intermediates from experts. PMID:23914275

Avoiding Treatment Interruptions: What Role Do Australian Community Pharmacists Play?

PubMed Central

Abukres, Salem Hasn; Hoti, Kreshnik; Hughes, Jeffery David

2016-01-01

Objective To explore the reported practice of Australian community pharmacists when dealing with medication supply requests in absence of a valid prescription. Methods Self-administered questionnaire was posted to 1490 randomly selected community pharmacies across all Australian states and territories. This sample was estimated to be a 20% of all Australian community pharmacies. Results Three hundred eighty five pharmacists participated in the study (response rate achieved was 27.9% (there were 111 undelivered questionnaires). Respondents indicated that they were more likely to provide medications to regular customers without a valid prescription compared to non-regular customers (p<0.0001). However, supply was also influenced by the type of prescription and the medication requested. In the case of type of prescription (Standard, Authority or Private) this relates to the complexity/probability of obtaining a valid prescription from the prescriber at a later date (i.e. supply with an anticipated prescription). Decisions to supply and/or not supply related to medication type were more complex. For some cases, including medication with potential for abuse, the practice and/or the method of supply varied significantly according to age and gender of the pharmacist, and pharmacy location (p<0.05). Conclusions Although being a regular customer does not guarantee a supply, results of this study reinforce the importance for patients having a regular pharmacy, where pharmacists were more likely to continue medication supply in cases of patients presenting without a valid prescription. We would suggest, more flexible legislation should be implemented to allow pharmacists to continue supplying of medication when obtaining a prescription is not practical. PMID:27170997

Evaluating acute medical admissions through emergency departments in Hong Kong: can one adjust for case-mix variation?

PubMed

Rainer, T H; Sollich, P; Piotrowski, T; Coolen, A C C; Cheng, B; Graham, C A

2012-12-01

Healthcare systems are under pressure to efficiently and safely reduce acute care admissions to hospital. There is a need to develop a standardised system for assessing emergency department performance which takes into account case-mix variation. The objective of this study was to derive and validate a standardised tool for assessing variations in medical admissions through emergency departments in Hong Kong. Retrospective study of patients attending emergency departments of 14 acute hospitals in Hong Kong. Data were retrieved from a centralised administrative database. Of 2,531,225 patients who attended emergency departments between 1 January 2001 and 31 December 2003, 780,444 (30.8%) were admitted to medical wards. A model derived from 2001 data shows well-calibrated admission probabilities, with an area under the receiver operating characteristic curve for probability of admission of 90.3 (95% CI ±0.11). The areas under the receiver operating characteristic curves for 2002 and 2003 validation sets were 89.9 (95% CI ±0.11) and 89.0 (95% CI ±0.12), respectively. With an averaged benchmark, reductions in medical admissions of up to 19% could be achieved, while under the most optimistic assumption, reductions of up 36% could be achieved. A tool for benchmarking hospital medical admissions and minimising case-mix variation has been derived and validated in Hong Kong, but it requires further validation in other healthcare systems given the wide variations in admission thresholds internationally. This may be used as one potential method to evaluate the performance of emergency departments against a common standard.

Positive predictive value of a case definition for diabetes mellitus using automated administrative health data in children and youth exposed to antipsychotic drugs or control medications: a Tennessee Medicaid study.

PubMed

Bobo, William V; Cooper, William O; Stein, C Michael; Olfson, Mark; Mounsey, Jackie; Daugherty, James; Ray, Wayne A

2012-08-24

We developed and validated an automated database case definition for diabetes in children and youth to facilitate pharmacoepidemiologic investigations of medications and the risk of diabetes. The present study was part of an in-progress retrospective cohort study of antipsychotics and diabetes in Tennessee Medicaid enrollees aged 6-24 years. Diabetes was identified from diabetes-related medical care encounters: hospitalizations, outpatient visits, and filled prescriptions. The definition required either a primary inpatient diagnosis or at least two other encounters of different types, most commonly an outpatient diagnosis with a prescription. Type 1 diabetes was defined by insulin prescriptions with at most one oral hypoglycemic prescription; other cases were considered type 2 diabetes. The definition was validated for cohort members in the 15 county region geographically proximate to the investigators. Medical records were reviewed and adjudicated for cases that met the automated database definition as well as for a sample of persons with other diabetes-related medical care encounters. The study included 64 cases that met the automated database definition. Records were adjudicated for 46 (71.9%), of which 41 (89.1%) met clinical criteria for newly diagnosed diabetes. The positive predictive value for type 1 diabetes was 80.0%. For type 2 and unspecified diabetes combined, the positive predictive value was 83.9%. The estimated sensitivity of the definition, based on adjudication for a sample of 30 cases not meeting the automated database definition, was 64.8%. These results suggest that the automated database case definition for diabetes may be useful for pharmacoepidemiologic studies of medications and diabetes.

Positive predictive value of a case definition for diabetes mellitus using automated administrative health data in children and youth exposed to antipsychotic drugs or control medications: a Tennessee Medicaid study

PubMed Central

2012-01-01

Background We developed and validated an automated database case definition for diabetes in children and youth to facilitate pharmacoepidemiologic investigations of medications and the risk of diabetes. Methods The present study was part of an in-progress retrospective cohort study of antipsychotics and diabetes in Tennessee Medicaid enrollees aged 6–24 years. Diabetes was identified from diabetes-related medical care encounters: hospitalizations, outpatient visits, and filled prescriptions. The definition required either a primary inpatient diagnosis or at least two other encounters of different types, most commonly an outpatient diagnosis with a prescription. Type 1 diabetes was defined by insulin prescriptions with at most one oral hypoglycemic prescription; other cases were considered type 2 diabetes. The definition was validated for cohort members in the 15 county region geographically proximate to the investigators. Medical records were reviewed and adjudicated for cases that met the automated database definition as well as for a sample of persons with other diabetes-related medical care encounters. Results The study included 64 cases that met the automated database definition. Records were adjudicated for 46 (71.9%), of which 41 (89.1%) met clinical criteria for newly diagnosed diabetes. The positive predictive value for type 1 diabetes was 80.0%. For type 2 and unspecified diabetes combined, the positive predictive value was 83.9%. The estimated sensitivity of the definition, based on adjudication for a sample of 30 cases not meeting the automated database definition, was 64.8%. Conclusion These results suggest that the automated database case definition for diabetes may be useful for pharmacoepidemiologic studies of medications and diabetes. PMID:22920280

Screening for Psychological Inflexibility: Initial Validation of the Avoidance and Fusion Questionnaire for Youth as a School Mental Health Screener

ERIC Educational Resources Information Center

Renshaw, Tyler L.

2017-01-01

The present study reports on the initial validation of the eight-item version of the Avoidance and Fusion Questionnaire for Youth (AFQ-Y8) as a school mental health screener for identifying clinical-level depression and anxiety caseness within a sample of urban high school students (N = 219). Results indicated that responses to the AFQ-Y8 yielded…

The Validation of a Case-Based, Cumulative Assessment and Progressions Examination

PubMed Central

Coker, Adeola O.; Copeland, Jeffrey T.; Gottlieb, Helmut B.; Horlen, Cheryl; Smith, Helen E.; Urteaga, Elizabeth M.; Ramsinghani, Sushma; Zertuche, Alejandra; Maize, David

2016-01-01

Objective. To assess content and criterion validity, as well as reliability of an internally developed, case-based, cumulative, high-stakes third-year Annual Student Assessment and Progression Examination (P3 ASAP Exam). Methods. Content validity was assessed through the writing-reviewing process. Criterion validity was assessed by comparing student scores on the P3 ASAP Exam with the nationally validated Pharmacy Curriculum Outcomes Assessment (PCOA). Reliability was assessed with psychometric analysis comparing student performance over four years. Results. The P3 ASAP Exam showed content validity through representation of didactic courses and professional outcomes. Similar scores on the P3 ASAP Exam and PCOA with Pearson correlation coefficient established criterion validity. Consistent student performance using Kuder-Richardson coefficient (KR-20) since 2012 reflected reliability of the examination. Conclusion. Pharmacy schools can implement internally developed, high-stakes, cumulative progression examinations that are valid and reliable using a robust writing-reviewing process and psychometric analyses. PMID:26941435

Control of a Vanadium Redox Battery and supercapacitor using a Three-Level Neutral Point Clamped converter

NASA Astrophysics Data System (ADS)

Etxeberria, A.; Vechiu, I.; Baudoin, S.; Camblong, H.; Kreckelbergh, S.

2014-02-01

The increasing use of distributed generators, which are mainly based on renewable sources, can create several issues in the operation of the electric grid. The microgrid is being analysed as a solution to the integration in the grid of the renewable sources at a high penetration level in a controlled way. The storage systems play a vital role in order to keep the energy and power balance of the microgrid. Due to the technical limitations of the currently available storage systems, it is necessary to use more than one storage technology to satisfy the requirements of the microgrid application. This work validates in simulations and experimentally the use of a Three-Level Neutral Point Clamped converter to control the power flow of a hybrid storage system formed by a SuperCapacitor and a Vanadium Redox Battery. The operation of the system is validated in two case studies in the experimental platform installed in ESTIA. The experimental results prove the validity of the proposed system as well as the designed control algorithm. The good agreement among experimental and simulation results also validates the simulation model, that can therefore be used to analyse the operation of the system in different case studies.

Non-invasive fetal sex determination by maternal plasma sequencing and application in X-linked disorder counseling.

PubMed

Pan, Xiaoyu; Zhang, Chunlei; Li, Xuchao; Chen, Shengpei; Ge, Huijuan; Zhang, Yanyan; Chen, Fang; Jiang, Hui; Jiang, Fuman; Zhang, Hongyun; Wang, Wei; Zhang, Xiuqing

2014-12-01

To develop a fetal sex determination method based on maternal plasma sequencing (MPS), assess its performance and potential use in X-linked disorder counseling. 900 cases of MPS data from a previous study were reviewed, in which 100 and 800 cases were used as training and validation set, respectively. The percentage of uniquely mapped sequencing reads on Y chromosome was calculated and used to classify male and female cases. Eight pregnant women who are carriers of Duchenne muscular dystrophy (DMD) mutations were recruited, whose plasma were subjected to multiplex sequencing and fetal sex determination analysis. In the training set, a sensitivity of 96% and false positive rate of 0% for male cases detection were reached in our method. The blinded validation results showed 421 in 423 male cases and 374 in 377 female cases were successfully identified, revealing sensitivity and specificity of 99.53% and 99.20% for fetal sex determination, at as early as 12 gestational weeks. Fetal sex for all eight DMD genetic counseling cases were correctly identified, which were confirmed by amniocentesis. Based on MPS, high accuracy of non-invasive fetal sex determination can be achieved. This method can potentially be used for prenatal genetic counseling.

PolarWindsII_DAWN_DC8_1

Atmospheric Science Data Center

2018-04-18

... Layer Winds Surface Winds Upper Level Winds Wind Profiles LIDAR Calibration/Validation Order Data:  ... Model Barrier Flow Case Study DAWN Coherent Wind Profiling Flights DAWN Overview and Preliminary Flight Results ...

Validation of software for calculating the likelihood ratio for parentage and kinship.

PubMed

Drábek, J

2009-03-01

Although the likelihood ratio is a well-known statistical technique, commercial off-the-shelf (COTS) software products for its calculation are not sufficiently validated to suit general requirements for the competence of testing and calibration laboratories (EN/ISO/IEC 17025:2005 norm) per se. The software in question can be considered critical as it directly weighs the forensic evidence allowing judges to decide on guilt or innocence or to identify person or kin (i.e.: in mass fatalities). For these reasons, accredited laboratories shall validate likelihood ratio software in accordance with the above norm. To validate software for calculating the likelihood ratio in parentage/kinship scenarios I assessed available vendors, chose two programs (Paternity Index and familias) for testing, and finally validated them using tests derived from elaboration of the available guidelines for the field of forensics, biomedicine, and software engineering. MS Excel calculation using known likelihood ratio formulas or peer-reviewed results of difficult paternity cases were used as a reference. Using seven testing cases, it was found that both programs satisfied the requirements for basic paternity cases. However, only a combination of two software programs fulfills the criteria needed for our purpose in the whole spectrum of functions under validation with the exceptions of providing algebraic formulas in cases of mutation and/or silent allele.

Development and validation of the Neonatal Mortality Score-9 Mexico to predict mortality in critically ill neonates.

PubMed

Márquez-González, Horacio; Jiménez-Báez, María Valeria; Muñoz-Ramírez, C Mireya; Yáñez-Gutiérrez, Lucelli; Huelgas-Plaza, Ana C; Almeida-Gutiérrez, Eduardo; Villa-Romero, Antonio Rafael

2015-06-01

Prognostic scales or scores are useful for physicians who work in neonatal intensive care units. There are several validated neonatal scores but they are mostly applicable to low birth weight infants. The aim of this study was to develop and validate a mortality prognostic score in newborn infants, that would include new prognostic outcome measures. The study was conducted in a mother and child hospital in the city of Mexico, part of the Instituto Mexicano del Seguro Social (Mexican Institute of Social Security). In the first phase of the study, a nested case-control study was designed (newborn infants admitted on the basis of severity criteria during the first day of life), in which a scale was identified and developed with gradual parameters of cumulative score consisting of nine independent outcome measures to predict death, as follows: weight, metabolic acidemia, lactate, PaO2/FiO2, p(A-a) O2, A/a, platelets and serum glucose.Validation was performed in a matched prospective cohort, using 7-day mortality as an endpoint. The initial cohort consisted of 424 newborn infants. Twenty-two cases and 132 controls were selected; and 9 outcome measures were identified, making up the scale named neonatal mortality score-9 Mexico. The validation cohort consisted of 227 newborn infants. Forty-four (19%) deaths were recorded, with an area under the curve (AUC) of 0.92. With a score between 16 and 18, an 85 (11-102) hazard ratio, 99% specificity, 71% positive predictive value and 90% negative predictive value were reported. Conclusions .The proposed scale is a reliable tool to predict severity in newborn infants.

Brief Report: Independent Validation of Autism Spectrum Disorder Case Status in the Utah Autism and Developmental Disabilities Monitoring (ADDM) Network Site

ERIC Educational Resources Information Center

Bakian, Amanda V.; Bilder, Deborah A.; Carbone, Paul S.; Hunt, Tyler D.; Petersen, Brent; Rice, Catherine E.

2015-01-01

An independent validation was conducted of the Utah Autism and Developmental Disabilities Monitoring Network's (UT-ADDM) classification of children with autism spectrum disorder (ASD). UT-ADDM final case status (n = 90) was compared with final case status as determined by independent external expert reviewers (EERs). Inter-rater reliability…

Modeling the Dynamic Interrelations between Mobility, Utility, and Land Asking Price

NASA Astrophysics Data System (ADS)

Hidayat, E.; Rudiarto, I.; Siegert, F.; Vries, W. D.

2018-02-01

Limited and insufficient information about the dynamic interrelation among mobility, utility, and land price is the main reason to conduct this research. Several studies, with several approaches, and several variables have been conducted so far in order to model the land price. However, most of these models appear to generate primarily static land prices. Thus, a research is required to compare, design, and validate different models which calculate and/or compare the inter-relational changes of mobility, utility, and land price. The applied method is a combination of analysis of literature review, expert interview, and statistical analysis. The result is newly improved mathematical model which have been validated and is suitable for the case study location. This improved model consists of 12 appropriate variables. This model can be implemented in the Salatiga city as the case study location in order to arrange better land use planning to mitigate the uncontrolled urban growth.

A review of published research on adult dissociative identity disorder: 2000-2010.

PubMed

Boysen, Guy A; VanBergen, Alexandra

2013-01-01

The purpose of this study was to assess the scientific and etiological status of dissociative identity disorder (DID) by examining cases published from 2000 to 2010. In terms of scientific status, DID is a small but ongoing field of study. The review yielded 21 case studies and 80 empirical studies, presenting data on 1171 new cases of DID. A mean of 9 articles, each containing a mean of 17 new cases of DID, emerged each year. In terms of etiological status, many of the central criticisms of the disorder's validity remain unaddressed. Most cases of DID emerged from a small number of countries and clinicians. In addition, documented cases occurring outside treatment were almost nonexistent. Finally, people simulating DID in the laboratory were mostly indistinguishable from individuals with DID. Overall, DID is still a topic of study, but the research lacks the productivity and focus needed to resolve ongoing controversies surrounding the disorder.

Second-Moment RANS Model Verification and Validation Using the Turbulence Modeling Resource Website (Invited)

NASA Technical Reports Server (NTRS)

Eisfeld, Bernhard; Rumsey, Chris; Togiti, Vamshi

2015-01-01

The implementation of the SSG/LRR-omega differential Reynolds stress model into the NASA flow solvers CFL3D and FUN3D and the DLR flow solver TAU is verified by studying the grid convergence of the solution of three different test cases from the Turbulence Modeling Resource Website. The model's predictive capabilities are assessed based on four basic and four extended validation cases also provided on this website, involving attached and separated boundary layer flows, effects of streamline curvature and secondary flow. Simulation results are compared against experimental data and predictions by the eddy-viscosity models of Spalart-Allmaras (SA) and Menter's Shear Stress Transport (SST).

Validation of Sea levels from coastal altimetry waveform retracking expert system: a case study around the Prince William Sound in Alaska

NASA Astrophysics Data System (ADS)

Idris, N. H.; Deng, X.; Idris, N. H.

2017-05-01

This paper presents the validation of Coastal Altimetry Waveform Retracking Expert System (CAWRES), a novel method to optimize the Jason satellite altimetric sea levels from multiple retracking solutions. The validation is conducted over the region of Prince William Sound in Alaska, USA, where altimetric waveforms are perturbed by emerged land and sea states. Validation is performed in twofold. First, comparison with existing retrackers (i.e. MLE4 and Ice) from the Sensor Geophysical Data Records (SGDR), and second, comparison with in-situ tide gauge data. From the first validation assessment, in general, CAWRES outperforms the MLE4 and Ice retrackers. In 4 out of 6 cases, the value of improvement percentage (standard deviation of difference) is higher (lower) than those of the SGDR retrackers. CAWRES also presents the best performance in producing valid observations, and has the lowest noise when compared to the SGDR retrackers. From the second assessment with tide gauge, CAWRES retracked sea level anomalies (SLAs) are consistent with those of the tide gauge. The accuracy of CAWRES retracked SLAs is slightly better than those of the MLE4. However, the performance of Ice retracker is better than those of CAWRES and MLE4, suggesting the empirical-based retracker is more effective. The results demonstrate that the CAWRES would have potential to be applied to coastal regions elsewhere.

Neuropathic pain phenotyping by international consensus (NeuroPPIC) for genetic studies: a NeuPSIG systematic review, Delphi survey, and expert panel recommendations

PubMed Central

van Hecke, Oliver; Kamerman, Peter R.; Attal, Nadine; Baron, Ralf; Bjornsdottir, Gyda; Bennett, David L.H.; Bennett, Michael I.; Bouhassira, Didier; Diatchenko, Luda; Freeman, Roy; Freynhagen, Rainer; Haanpää, Maija; Jensen, Troels S.; Raja, Srinivasa N.; Rice, Andrew S.C.; Seltzer, Ze'ev; Thorgeirsson, Thorgeir E.; Yarnitsky, David; Smith, Blair H.

2015-01-01

Abstract For genetic research to contribute more fully to furthering our knowledge of neuropathic pain, we require an agreed, valid, and feasible approach to phenotyping, to allow collaboration and replication in samples of sufficient size. Results from genetic studies on neuropathic pain have been inconsistent and have met with replication difficulties, in part because of differences in phenotypes used for case ascertainment. Because there is no consensus on the nature of these phenotypes, nor on the methods of collecting them, this study aimed to provide guidelines on collecting and reporting phenotypes in cases and controls for genetic studies. Consensus was achieved through a staged approach: (1) systematic literature review to identify all neuropathic pain phenotypes used in previous genetic studies; (2) Delphi survey to identify the most useful neuropathic pain phenotypes and their validity and feasibility; and (3) meeting of experts to reach consensus on the optimal phenotype(s) to be collected from patients with neuropathic pain for genetic studies. A basic “entry level” set of phenotypes was identified for any genetic study of neuropathic pain. This set identifies cases of “possible” neuropathic pain, and controls, and includes: (1) a validated symptom-based questionnaire to determine whether any pain is likely to be neuropathic; (2) body chart or checklist to identify whether the area of pain distribution is neuroanatomically logical; and (3) details of pain history (intensity, duration, any formal diagnosis). This NeuroPPIC “entry level” set of phenotypes can be expanded by more extensive and specific measures, as determined by scientific requirements and resource availability. PMID:26469320

Measuring quality of life in dyspeptic patients: development and validation of a new specific health status questionnaire: final report from the Italian QPD project involving 4000 patients.

PubMed

Bamfi, F; Olivieri, A; Arpinelli, F; De Carli, G; Recchia, G; Gandolfi, L; Norberto, L; Pacini, F; Surrenti, C; Irvine, S H; Apolone, G

1999-03-01

Despite the fact that gastrointestinal disorders represent one of the most common reasons for medical consultations, formal assessment of patients' health-related quality of life (HRQOL) has been carried out only in a few studies, and in most cases generic questionnaires have been adopted. Because the specific issue of living with dyspeptic problems has been addressed in very few cases and no questionnaire has been shown to be appropriate for the Italian setting, a prospective project was launched to develop a specific HRQOL questionnaire for dyspepsia sufferers tailored to Italian patients but also appropriate in other cultural settings. The project consisted in a 3-yr, three-phase survey, in which different versions of the quality of life in peptic disease questionnaire (QPD) were developed through expert and patient focus groups and empiric field studies and then administered to patients recruited in five multicenter studies. Standard psychometric techniques were used to evaluate the validity, reliability, responsiveness, and patient acceptability of the QPD. Three different versions of the QPD questionnaire were self-administered to more than 4000 patients. The final 30-item version, measuring three health concepts related to dyspeptic disease (anxiety induced by pain, social restriction, symptom perception), fulfilled the recommended psychometric criteria in terms of reliability and validity, correlated with health concepts measured with a well-known independent generic HRQOL instrument (the SF-36 Health Survey questionnaire) and was relatively invariant to diagnosis and sociodemographic variables; it also correlated with a measure of gastric pain frequency and was able to detect meaningful differences over time. Although further validation studies in different cultural and linguistic settings are mandatory before any firm conclusions can be drawn regarding the cross-cultural validity of the QPD, the data obtained provide evidence of the psychometric validity and robustness of the questionnaire when used in a fairly large, well-characterized population of Italian dyspeptic patients.

NCI-FDA Interagency Oncology Task Force Workshop Provides Guidance for Analytical Validation of Protein-based Multiplex Assays | Office of Cancer Clinical Proteomics Research

Cancer.gov

An NCI-FDA Interagency Oncology Task Force (IOTF) Molecular Diagnostics Workshop was held on October 30, 2008 in Cambridge, MA, to discuss requirements for analytical validation of protein-based multiplex technologies in the context of its intended use. This workshop developed through NCI's Clinical Proteomic Technologies for Cancer initiative and the FDA focused on technology-specific analytical validation processes to be addressed prior to use in clinical settings. In making this workshop unique, a case study approach was used to discuss issues related to

Incidence of auto-immune pemphigus in the Midi-Pyrénées region in 2002-2006.

PubMed

Thomas, M; Paul, C; Berard, E; Fortenfant, F; Mazereeuw-Hautier, J; Livideanu, C; Viraben, R; Meyer, N

2010-01-01

Auto-immune pemphigus is an organ-specific immune disorder due to pathogenic auto-antibodies. Both genetic and environmental factors have been associated with the occurrence of auto-immune pemphigus. Little is known about the epidemiology of auto-immune pemphigus in western Europe. To evaluate the incidence of auto-immune pemphigus in south-western France (namely the Midi-Pyrénées region) in a 5-year period between 2002 and 2006. We performed a retrospective study of the annual incidence of auto-immune pemphigus diagnosed in the Midi-Pyrénées region, between January 1, 2002, and December 31, 2006. Possible cases of pemphigus were initially selected using skin direct immunofluorescence (DIF) databases from all laboratories in the Midi-Pyrénées region. Systematic validation of all cases was performed by two of the authors (N.M., M.T.). To qualify as a case of auto-immune pemphigus, patients had to fulfil the following criteria: history of clinical signs of pemphigus as assessed by a dermatologist and a positive DIF. To be included in the study, validated cases of auto-immune pemphigus had to fulfil the following criteria: the date of first positive skin DIF between January 1, 2002, and December 31, 2006, and patient living in the Midi-Pyrénées region at the time of the first positive skin DIF. Between 2002 and 2006, 91 patients with positive DIF were identified. Fifty-four patients with positive DIF did not meet the validation criteria for the study. Thirty-seven cases were included in the analysis. The crude annual mean incidence of auto-immune pemphigus between 2002 and 2006 was 2.7 cases/10(6) inhabitants/year (95% CI: 1.87-3.69). The world-population-standardized annual mean incidence of auto-immune pemphigus was 1.55 (95% CI: 0.99-2.11). We report a 1.55/10(6) inhabitants/year world-population-standardized incidence of auto-immune pemphigus in the south-west of France. A nationwide epidemiological study of pemphigus should be performed in France.

A novel approach for medical research on lymphomas

PubMed Central

Conte, Cécile; Palmaro, Aurore; Grosclaude, Pascale; Daubisse-Marliac, Laetitia; Despas, Fabien; Lapeyre-Mestre, Maryse

2018-01-01

Abstract The use of claims database to study lymphomas in real-life conditions is a crucial issue in the future. In this way, it is essential to develop validated algorithms for the identification of lymphomas in these databases. The aim of this study was to assess the validity of diagnosis codes in the French health insurance database to identify incident cases of lymphomas according to results of a regional cancer registry, as the gold standard. Between 2010 and 2013, incident lymphomas were identified in hospital data through 2 algorithms of selection. The results of the identification process and characteristics of incident lymphomas cases were compared with data from the Tarn Cancer Registry. Each algorithm's performance was assessed by estimating sensitivity, predictive positive value, specificity (SPE), and negative predictive value. During the period, the registry recorded 476 incident cases of lymphomas, of which 52 were Hodgkin lymphomas and 424 non-Hodgkin lymphomas. For corresponding area and period, algorithm 1 provides a number of incident cases close to the Registry, whereas algorithm 2 overestimated the number of incident cases by approximately 30%. Both algorithms were highly specific (SPE = 99.9%) but moderately sensitive. The comparative analysis illustrates that similar distribution and characteristics are observed in both sources. Given these findings, the use of claims database can be consider as a pertinent and powerful tool to conduct medico-economic or pharmacoepidemiological studies in lymphomas. PMID:29480830

ME 5620 Fracture Mechanics in Engineering Design. Case Study Project

DTIC Science & Technology

2011-04-03

14 UNCLASSIFIED References 1 . A First Course in the Finite Element Method, 4th edition, by D.L. Logan, Thomson Engineering, 2006. 2. Altair ...collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources...currently valid OMB control number. 1 . REPORT DATE 03 APR 2011 2. REPORT TYPE N/A 3. DATES COVERED - 4. TITLE AND SUBTITLE Case Study

Application of the Analog Method to Modelling Heat Waves: A Case Study with Power Transformers

DTIC Science & Technology

2017-04-21

UNCLASSIFIED Massachusetts Institute of Technology Lincoln Laboratory APPLICATION OF THE ANALOG METHOD TO MODELLING HEAT WAVES: A CASE STUDY WITH...18 2 Calibration and validation statistics with the use of five atmospheric vari- ables to construct analogue diagnostics for JJA of transformer T2...electrical grid as a series of nodes (transformers) and edges (transmission lines) so that basic mathematical anal- ysis can be performed. The mathematics

Validation of key indicators in cattle farms at high risk of animal welfare problems: a qualitative case-control study.

PubMed

Kelly, P C; More, S J; Blake, M; Higgins, I; Clegg, T; Hanlon, A

2013-03-23

The objective of this study was to validate four key farmer performance indicators (KFPI), identified in a previous study, as indicators of on-farm cattle welfare incidents in Ireland, through comparison of the distribution of these KPFIs in the national herd (n=109,925) and in case herds (n=18), where welfare incidents were previously studied. The KFPIs identified were late registrations, and exits from the herd by on-farm burial, by moves to knackeries and by moves to 'herd unknown'. Data were extracted from two Department of Agriculture, Food and the Marine databases for the national herd and the case herds. All four KFPIs differed significantly between the case herds and the national herd, and one further KFPI was identified, namely moves to factories. The data for these KFPIs are routinely stored on national databases, which were established in order to comply with Regulation (EC) 1760/2000. Based on the results obtained in this study, it may be possible in the future to use routine data capture to improve strategy towards on-farm animal welfare. At this point, however, based on calculated specificities and sensitivities, none of these five KFPIs, at the cut-offs investigated and using several combinations, are able to distinguish herds with and without on-farm animal welfare problems at an accuracy suitable for routine national use in Ireland.

Verification and Validation in a Rapid Software Development Process

NASA Technical Reports Server (NTRS)

Callahan, John R.; Easterbrook, Steve M.

1997-01-01

The high cost of software production is driving development organizations to adopt more automated design and analysis methods such as rapid prototyping, computer-aided software engineering (CASE) tools, and high-level code generators. Even developers of safety-critical software system have adopted many of these new methods while striving to achieve high levels Of quality and reliability. While these new methods may enhance productivity and quality in many cases, we examine some of the risks involved in the use of new methods in safety-critical contexts. We examine a case study involving the use of a CASE tool that automatically generates code from high-level system designs. We show that while high-level testing on the system structure is highly desirable, significant risks exist in the automatically generated code and in re-validating releases of the generated code after subsequent design changes. We identify these risks and suggest process improvements that retain the advantages of rapid, automated development methods within the quality and reliability contexts of safety-critical projects.

A methodology to estimate representativeness of LAI station observation for validation: a case study with Chinese Ecosystem Research Network (CERN) in situ data

NASA Astrophysics Data System (ADS)

Xu, Baodong; Li, Jing; Liu, Qinhuo; Zeng, Yelu; Yin, Gaofei

2014-11-01

Leaf Area Index (LAI) is known as a key vegetation biophysical variable. To effectively use remote sensing LAI products in various disciplines, it is critical to understand the accuracy of them. The common method for the validation of LAI products is firstly establish the empirical relationship between the field data and high-resolution imagery, to derive LAI maps, then aggregate high-resolution LAI maps to match moderate-resolution LAI products. This method is just suited for the small region, and its frequencies of measurement are limited. Therefore, the continuous observing LAI datasets from ground station network are important for the validation of multi-temporal LAI products. However, due to the scale mismatch between the point observation in the ground station and the pixel observation, the direct comparison will bring the scale error. Thus it is needed to evaluate the representativeness of ground station measurement within pixel scale of products for the reasonable validation. In this paper, a case study with Chinese Ecosystem Research Network (CERN) in situ data was taken to introduce a methodology to estimate representativeness of LAI station observation for validating LAI products. We first analyzed the indicators to evaluate the observation representativeness, and then graded the station measurement data. Finally, the LAI measurement data which can represent the pixel scale was used to validate the MODIS, GLASS and GEOV1 LAI products. The result shows that the best agreement is reached between the GLASS and GEOV1, while the lowest uncertainty is achieved by GEOV1 followed by GLASS and MODIS. We conclude that the ground station measurement data can validate multi-temporal LAI products objectively based on the evaluation indicators of station observation representativeness, which can also improve the reliability for the validation of remote sensing products.

Remote Sensing of Water Quality in Multipurpose Reservoirs: Case Study Applications in Indonesia, Mexico, and Uruguay

NASA Astrophysics Data System (ADS)

Miralles-Wilhelm, F.; Serrat-Capdevila, A.; Rodriguez, D.

2017-12-01

This research is focused on development of remote sensing methods to assess surface water pollution issues, particularly in multipurpose reservoirs. Three case study applications are presented to comparatively analyze remote sensing techniquesforo detection of nutrient related pollution, i.e., Nitrogen, Phosphorus, Chlorophyll, as this is a major water quality issue that has been identified in terms of pollution of major water sources around the country. This assessment will contribute to a better understanding of options for nutrient remote sensing capabilities and needs and assist water agencies in identifying the appropriate remote sensing tools and devise an application strategy to provide information needed to support decision-making regarding the targeting and monitoring of nutrient pollution prevention and mitigation measures. A detailed review of the water quality data available from ground based measurements was conducted in order to determine their suitability for a case study application of remote sensing. In the first case study, the Valle de Bravo reservoir in Mexico City reservoir offers a larger database of water quality which may be used to better calibrate and validate the algorithms required to obtain water quality data from remote sensing raw data. In the second case study application, the relatively data scarce Lake Toba in Indonesia can be useful to illustrate the value added of remote sensing data in locations where water quality data is deficient or inexistent. The third case study in the Paso Severino reservoir in Uruguay offers a combination of data scarcity and persistent development of harmful algae blooms. Landsat-TM data was obteined for the 3 study sites and algorithms for three key water quality parameters that are related to nutrient pollution: Chlorophyll-a, Total Nitrogen, and Total Phosphorus were calibrated and validated at the study sites. The three case study applications were developed into capacity building/training workshops for water resources students, applied scientists, practitioners, reservoir and water quality managers, and other interested stakeholders.

Population versus hospital controls for case-control studies on cancers in Chinese hospitals

PubMed Central

2011-01-01

Background Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. Methods We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. Results The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively. Conclusions The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting. PMID:22171783

Population versus hospital controls for case-control studies on cancers in Chinese hospitals.

PubMed

Li, Lin; Zhang, Min; Holman, D'Arcy

2011-12-15

Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting. We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses. The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively. The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting.

The validity of tooth grinding measures: etiology of pain dysfunction syndrome revisited.

PubMed

Marbach, J J; Raphael, K G; Dohrenwend, B P; Lennon, M C

1990-03-01

The current study explores the proposition that a treating clinician's etiologic model influences patients' reports of tooth grinding, the validity of, and subsequent research findings relying on these measures. The investigation compares self-reports of tooth grinding and related clinical variables for 151 cases of temporomandibular pain and dysfunction syndrome (TMPDS) treated by a clinician who does not explicitly support the grinding theory of the etiology of TMPDS, and 139 healthy controls. Cases were no more likely than well controls to report ever-grinding, but were actually significantly less likely than well controls to report current grinding. They were also significantly more likely to report that a dentist had told them they ground. Findings suggest that studies using self-report, clinician-report of tooth grinding (or both) are methodologically inadequate for addressing the relationship between tooth grinding and TMPDS.

A Conceptual Framework for Decision-making Support in Uncertainty- and Risk-based Diagnosis of Rare Clinical Cases by Specialist Physicians.

PubMed

Santos, Adriano A; Moura, J Antão B; de Araújo, Joseana Macêdo Fechine Régis

2015-01-01

Mitigating uncertainty and risks faced by specialist physicians in analysis of rare clinical cases is something desired by anyone who needs health services. The number of clinical cases never seen by these experts, with little documentation, may introduce errors in decision-making. Such errors negatively affect well-being of patients, increase procedure costs, rework, health insurance premiums, and impair the reputation of specialists and medical systems involved. In this context, IT and Clinical Decision Support Systems (CDSS) play a fundamental role, supporting decision-making process, making it more efficient and effective, reducing a number of avoidable medical errors and enhancing quality of treatment given to patients. An investigation has been initiated to look into characteristics and solution requirements of this problem, model it, propose a general solution in terms of a conceptual risk-based, automated framework to support rare-case medical diagnostics and validate it by means of case studies. A preliminary validation study of the proposed framework has been carried out by interviews conducted with experts who are practicing professionals, academics, and researchers in health care. This paper summarizes the investigation and its positive results. These results motivate continuation of research towards development of the conceptual framework and of a software tool that implements the proposed model.

BrainCheck - a very brief tool to detect incipient cognitive decline: optimized case-finding combining patient- and informant-based data.

PubMed

Ehrensperger, Michael M; Taylor, Kirsten I; Berres, Manfred; Foldi, Nancy S; Dellenbach, Myriam; Bopp, Irene; Gold, Gabriel; von Gunten, Armin; Inglin, Daniel; Müri, René; Rüegger, Brigitte; Kressig, Reto W; Monsch, Andreas U

2014-01-01

Optimal identification of subtle cognitive impairment in the primary care setting requires a very brief tool combining (a) patients' subjective impairments, (b) cognitive testing, and (c) information from informants. The present study developed a new, very quick and easily administered case-finding tool combining these assessments ('BrainCheck') and tested the feasibility and validity of this instrument in two independent studies. We developed a case-finding tool comprised of patient-directed (a) questions about memory and depression and (b) clock drawing, and (c) the informant-directed 7-item version of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). Feasibility study: 52 general practitioners rated the feasibility and acceptance of the patient-directed tool. Validation study: An independent group of 288 Memory Clinic patients (mean ± SD age = 76.6 ± 7.9, education = 12.0 ± 2.6; 53.8% female) with diagnoses of mild cognitive impairment (n = 80), probable Alzheimer's disease (n = 185), or major depression (n = 23) and 126 demographically matched, cognitively healthy volunteer participants (age = 75.2 ± 8.8, education = 12.5 ± 2.7; 40% female) partook. All patient and healthy control participants were administered the patient-directed tool, and informants of 113 patient and 70 healthy control participants completed the very short IQCODE. Feasibility study: General practitioners rated the patient-directed tool as highly feasible and acceptable. Validation study: A Classification and Regression Tree analysis generated an algorithm to categorize patient-directed data which resulted in a correct classification rate (CCR) of 81.2% (sensitivity = 83.0%, specificity = 79.4%). Critically, the CCR of the combined patient- and informant-directed instruments (BrainCheck) reached nearly 90% (that is 89.4%; sensitivity = 97.4%, specificity = 81.6%). A new and very brief instrument for general practitioners, 'BrainCheck', combined three sources of information deemed critical for effective case-finding (that is, patients' subject impairments, cognitive testing, informant information) and resulted in a nearly 90% CCR. Thus, it provides a very efficient and valid tool to aid general practitioners in deciding whether patients with suspected cognitive impairments should be further evaluated or not ('watchful waiting').

Does case misclassification threaten the validity of studies investigating the relationship between neck manipulation and vertebral artery dissection stroke? No.

PubMed

Murphy, Donald R; Schneider, Michael J; Perle, Stephen M; Bise, Christopher G; Timko, Michael; Haas, Mitchell

2016-01-01

The purported relationship between cervical manipulative therapy (CMT) and stroke related to vertebral artery dissection (VAD) has been debated for several decades. A large number of publications, from case reports to case-control studies, have investigated this relationship. A recent article suggested that case misclassification in the case-control studies on this topic resulted in biased odds ratios in those studies. Given its rarity, the best epidemiologic research design for investigating the relationship between CMT and VAD is the case-control study. The addition of a case-crossover aspect further strengthens the scientific rigor of such studies by reducing bias. The most recent studies investigating the relationship between CMT and VAD indicate that the relationship is not causal. In fact, a comparable relationship between vertebral artery-related stroke and visits to a primary care physician has been observed. The statistical association between visits to chiropractors and VAD can best be explained as resulting from a patient with early manifestation of VAD (neck pain with or without headache) seeking the services of a chiropractor for relief of this pain. Sometime after the visit the patient experiences VAD-related stroke that would have occurred regardless of the care received. This explanation has been challenged by a recent article putting forth the argument that case misclassification is likely to have biased the odds ratios of the case-control studies that have investigated the association between CMT and vertebral artery related stroke. The challenge particularly focused on one of the case-control studies, which had concluded that the association between CMT and vertebral artery related stroke was not causal. It was suggested by the authors of the recent article that misclassification led to an underestimation of risk. We argue that the information presented in that article does not support the authors' claim for a variety of reasons, including the fact that the assumptions upon which their analysis is based lack substantiation and the fact that any possible misclassification would not have changed the conclusion of the study in question. Current evidence does not support the notion that misclassification threatens the validity of recent case-control studies investigating the relationship between CMT and VAD. Hence, the recent re-analysis cannot refute the conclusion from previous studies that CMT is not a cause of VAD.

Group Sequential Testing of the Predictive Accuracy of a Continuous Biomarker with Unknown Prevalence

PubMed Central

Koopmeiners, Joseph S.; Feng, Ziding

2015-01-01

Group sequential testing procedures have been proposed as an approach to conserving resources in biomarker validation studies. Previously, Koopmeiners and Feng (2011) derived the asymptotic properties of the sequential empirical positive predictive value (PPV) and negative predictive value curves, which summarize the predictive accuracy of a continuous marker, under case-control sampling. A limitation of their approach is that the prevalence can not be estimated from a case-control study and must be assumed known. In this manuscript, we consider group sequential testing of the predictive accuracy of a continuous biomarker with unknown prevalence. First, we develop asymptotic theory for the sequential empirical PPV and NPV curves when the prevalence must be estimated, rather than assumed known in a case-control study. We then discuss how our results can be combined with standard group sequential methods to develop group sequential testing procedures and bias-adjusted estimators for the PPV and NPV curve. The small sample properties of the proposed group sequential testing procedures and estimators are evaluated by simulation and we illustrate our approach in the context of a study to validate a novel biomarker for prostate cancer. PMID:26537180

A Metric-Based Validation Process to Assess the Realism of Synthetic Power Grids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Birchfield, Adam; Schweitzer, Eran; Athari, Mir

Public power system test cases that are of high quality benefit the power systems research community with expanded resources for testing, demonstrating, and cross-validating new innovations. Building synthetic grid models for this purpose is a relatively new problem, for which a challenge is to show that created cases are sufficiently realistic. This paper puts forth a validation process based on a set of metrics observed from actual power system cases. These metrics follow the structure, proportions, and parameters of key power system elements, which can be used in assessing and validating the quality of synthetic power grids. Though wide diversitymore » exists in the characteristics of power systems, the paper focuses on an initial set of common quantitative metrics to capture the distribution of typical values from real power systems. The process is applied to two new public test cases, which are shown to meet the criteria specified in the metrics of this paper.« less

Radiant Energy Measurements from a Scaled Jet Engine Axisymmetric Exhaust Nozzle for a Baseline Code Validation Case

NASA Technical Reports Server (NTRS)

Baumeister, Joseph F.

1994-01-01

A non-flowing, electrically heated test rig was developed to verify computer codes that calculate radiant energy propagation from nozzle geometries that represent aircraft propulsion nozzle systems. Since there are a variety of analysis tools used to evaluate thermal radiation propagation from partially enclosed nozzle surfaces, an experimental benchmark test case was developed for code comparison. This paper briefly describes the nozzle test rig and the developed analytical nozzle geometry used to compare the experimental and predicted thermal radiation results. A major objective of this effort was to make available the experimental results and the analytical model in a format to facilitate conversion to existing computer code formats. For code validation purposes this nozzle geometry represents one validation case for one set of analysis conditions. Since each computer code has advantages and disadvantages based on scope, requirements, and desired accuracy, the usefulness of this single nozzle baseline validation case can be limited for some code comparisons.

A Metric-Based Validation Process to Assess the Realism of Synthetic Power Grids

DOE PAGES

Birchfield, Adam; Schweitzer, Eran; Athari, Mir; ...

2017-08-19

Public power system test cases that are of high quality benefit the power systems research community with expanded resources for testing, demonstrating, and cross-validating new innovations. Building synthetic grid models for this purpose is a relatively new problem, for which a challenge is to show that created cases are sufficiently realistic. This paper puts forth a validation process based on a set of metrics observed from actual power system cases. These metrics follow the structure, proportions, and parameters of key power system elements, which can be used in assessing and validating the quality of synthetic power grids. Though wide diversitymore » exists in the characteristics of power systems, the paper focuses on an initial set of common quantitative metrics to capture the distribution of typical values from real power systems. The process is applied to two new public test cases, which are shown to meet the criteria specified in the metrics of this paper.« less

Validity of Heart Failure Diagnoses in Administrative Databases: A Systematic Review and Meta-Analysis

PubMed Central

McCormick, Natalie; Lacaille, Diane; Bhole, Vidula; Avina-Zubieta, J. Antonio

2014-01-01

Objective Heart failure (HF) is an important covariate and outcome in studies of elderly populations and cardiovascular disease cohorts, among others. Administrative data is increasingly being used for long-term clinical research in these populations. We aimed to conduct the first systematic review and meta-analysis of studies reporting on the validity of diagnostic codes for identifying HF in administrative data. Methods MEDLINE and EMBASE were searched (inception to November 2010) for studies: (a) Using administrative data to identify HF; or (b) Evaluating the validity of HF codes in administrative data; and (c) Reporting validation statistics (sensitivity, specificity, positive predictive value [PPV], negative predictive value, or Kappa scores) for HF, or data sufficient for their calculation. Additional articles were located by hand search (up to February 2011) of original papers. Data were extracted by two independent reviewers; article quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. Using a random-effects model, pooled sensitivity and specificity values were produced, along with estimates of the positive (LR+) and negative (LR−) likelihood ratios, and diagnostic odds ratios (DOR = LR+/LR−) of HF codes. Results Nineteen studies published from1999–2009 were included in the qualitative review. Specificity was ≥95% in all studies and PPV was ≥87% in the majority, but sensitivity was lower (≥69% in ≥50% of studies). In a meta-analysis of the 11 studies reporting sensitivity and specificity values, the pooled sensitivity was 75.3% (95% CI: 74.7–75.9) and specificity was 96.8% (95% CI: 96.8–96.9). The pooled LR+ was 51.9 (20.5–131.6), the LR− was 0.27 (0.20–0.37), and the DOR was 186.5 (96.8–359.2). Conclusions While most HF diagnoses in administrative databases do correspond to true HF cases, about one-quarter of HF cases are not captured. The use of broader search parameters, along with laboratory and prescription medication data, may help identify more cases. PMID:25126761

Recruiting Hispanic women for a population-based study: validity of surname search and characteristics of nonparticipants.

PubMed

Sweeney, Carol; Edwards, Sandra L; Baumgartner, Kathy B; Herrick, Jennifer S; Palmer, Leslie E; Murtaugh, Maureen A; Stroup, Antoinette; Slattery, Martha L

2007-11-15

Conducting research on the health of Hispanic populations in the United States entails challenges of identifying individuals who are Hispanic and obtaining good study participation. In this report, identification of Hispanics using a surname search and ethnicity information collected by cancer registries was validated, compared with self-report, for breast cancer cases and controls in Utah and New Mexico. Factors influencing participation by Hispanics in a study interview in 2000-2005 were evaluated. The positive predictive value of identification as Hispanic by cancer registry records and surname search was 82.3% for cases and 73.2% for controls. Hispanics who were correctly classified differed from those who were misclassified, reporting lower language acculturation and educational attainment. Older age was positively associated with success in contacting Hispanic controls (p(trend) < 0.0001) but negatively associated with cooperation with the interview (p(trend) < 0.0001). Community characteristics described by US Census data, including income, education, and urban/rural residence, did not significantly influence participation by Hispanic cases or controls. The authors conclude that a surname search efficiently identifies Hispanics, although individuals identified using this method are not completely representative. Recruitment of Hispanic cases and controls does not appear to be affected by selection bias related to community characteristics.

Evaluation of surveillance case definition in the diagnosis of leptospirosis, using the Microscopic Agglutination Test: a validation study.

PubMed

Dassanayake, Dinesh L B; Wimalaratna, Harith; Agampodi, Suneth B; Liyanapathirana, Veranja C; Piyarathna, Thibbotumunuwe A C L; Goonapienuwala, Bimba L

2009-04-22

Leptospirosis is endemic in both urban and rural areas of Sri Lanka and there had been many out breaks in the recent past. This study was aimed at validating the leptospirosis surveillance case definition, using the Microscopic Agglutination Test (MAT). The study population consisted of patients with undiagnosed acute febrile illness who were admitted to the medical wards of the Teaching Hospital Kandy, from 1st July 2007 to 31st July 2008. The subjects were screened to diagnose leptospirosis according to the leptospirosis case definition. MAT was performed on blood samples taken from each patient on the 7th day of fever. Leptospirosis case definition was evaluated in regard to sensitivity, specificity and predictive values, using a MAT titre >or= 1:800 for confirming leptospirosis. A total of 123 patients were initially recruited of which 73 had clinical features compatible with the surveillance case definition. Out of the 73 only 57 had a positive MAT result (true positives) leaving 16 as false positives. Out of the 50 who didn't have clinical features compatible with the case definition 45 had a negative MAT as well (true negatives), therefore 5 were false negatives. Total number of MAT positives was 62 out of 123. According to these results the test sensitivity was 91.94%, specificity 73.77%, positive predictive value and negative predictive values were 78.08% and 90% respectively. Diagnostic accuracy of the test was 82.93%. This study confirms that the surveillance case definition has a very high sensitivity and negative predictive value with an average specificity in diagnosing leptospirosis, based on a MAT titre of >or= 1: 800.

Evaluation of PDA Technical Report No 33. Statistical Testing Recommendations for a Rapid Microbiological Method Case Study.

PubMed

Murphy, Thomas; Schwedock, Julie; Nguyen, Kham; Mills, Anna; Jones, David

2015-01-01

New recommendations for the validation of rapid microbiological methods have been included in the revised Technical Report 33 release from the PDA. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This case study applies those statistical methods to accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological methods system being evaluated for water bioburden testing. Results presented demonstrate that the statistical methods described in the PDA Technical Report 33 chapter can all be successfully applied to the rapid microbiological method data sets and gave the same interpretation for equivalence to the standard method. The rapid microbiological method was in general able to pass the requirements of PDA Technical Report 33, though the study shows that there can be occasional outlying results and that caution should be used when applying statistical methods to low average colony-forming unit values. Prior to use in a quality-controlled environment, any new method or technology has to be shown to work as designed by the manufacturer for the purpose required. For new rapid microbiological methods that detect and enumerate contaminating microorganisms, additional recommendations have been provided in the revised PDA Technical Report No. 33. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This paper applies those statistical methods to analyze accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological method system being validated for water bioburden testing. The case study demonstrates that the statistical methods described in the PDA Technical Report No. 33 chapter can be successfully applied to rapid microbiological method data sets and give the same comparability results for similarity or difference as the standard method. © PDA, Inc. 2015.

Face, content, and construct validity of four, inanimate training exercises using the da Vinci ® Si surgical system configured with Single-Site ™ instrumentation.

PubMed

Jarc, Anthony M; Curet, Myriam

2015-08-01

Validated training exercises are essential tools for surgeons as they develop technical skills to use robot-assisted minimally invasive surgical systems. The purpose of this study was to show face, content, and construct validity of four, inanimate training exercises using the da Vinci (®) Si surgical system configured with Single-Site (™) instrumentation. New (N = 21) and experienced (N = 6) surgeons participated in the study. New surgeons (11 Gynecology [GYN] and 10 General Surgery [GEN]) had not completed any da Vinci Single-Site cases but may have completed multiport cases using the da Vinci system. They participated in this study prior to attending a certification course focused on da Vinci Single-Site instrumentation. Experienced surgeons (5 GYN and 1 GEN) had completed at least 25 da Vinci Single-Site cases. The surgeons completed four inanimate training exercises and then rated them with a questionnaire. Raw metrics and overall normalized scores were computed using both video recordings and kinematic data collected from the surgical system. The experienced surgeons significantly outperformed new surgeons for many raw metrics and the overall normalized scores derived from video review (p < 0.05). Only one exercise did not achieve a significant difference between new and experienced surgeons (p = 0.08) when calculating an overall normalized score using both video and advanced metrics derived from kinematic data. Both new and experienced surgeons rated the training exercises as appearing, to train and measure technical skills used during da Vinci Single-Site surgery and actually testing the technical skills used during da Vinci Single-Site surgery. In summary, the four training exercises showed face, content, and construct validity. Improved overall scores could be developed using additional metrics not included in this study. The results suggest that the training exercises could be used in an overall training curriculum aimed at developing proficiency in technical skills for surgeons new to da Vinci Single-Site instrumentation.

Diagnosis and Medication Overload? A Nurse Review of the Psychiatric Histories of Older Youth in Treatment Foster Care

ERIC Educational Resources Information Center

Narendorf, Sarah Carter; Bertram, Julie; McMillen, J. Curtis

2011-01-01

Prior research has raised concern about the appropriateness of psychotropic medication use and the validity of psychiatric diagnosing for youth in child welfare but has lacked in-depth case information. This study reports results from a psychiatric nurse review conducted with eight youth entering a foster care intervention using case records and…

Under-reporting of tuberculosis in Praia, Cape Verde, from 2006 to 2012.

PubMed

Furtado da Luz, E; Braga, J U

2018-03-01

According to World Health Organization (WHO) estimates, the under-reporting rate for tuberculosis (TB) in Cape Verde between 2006 and 2012 was 49%. However, the WHO recognises the challenges associated with this estimation process and recommends implementing other methods, such as record linkage, to combat TB under-reporting. To estimate and analyse under-reporting of cases by TB surveillance health units and to evaluate TB cases retrieved from other TB diagnostic sources in Praia, Cape Verde, from 2006 to 2012. This cross-sectional study evaluated under-reporting using the following data: 1) the under-reporting index from TB reporting health units (RHUs), where the number of validated TB cases from RHUs was compared with data from the National Programme for the Fight against Tuberculosis and Leprosy (NPFTL); and 2) the under-reporting index among overall data sources, or a comparison of the number of all validated TB cases from all sources with NPFTL data. The TB under-reporting rate was 40% in Praia during the study period, and results were influenced by laboratory findings. The TB under-reporting rate was very similar to the rate estimated by the WHO. TB surveillance must be improved to reduce under-reporting.

"It was only harmless banter!" The development and preliminary validation of the moral disengagement in sexual harassment scale.

PubMed

Page, Thomas E; Pina, Afroditi; Giner-Sorolla, Roger

2016-01-01

Sexual harassment represents aggressive behavior that is often enacted instrumentally, in response to a threatened sense of masculinity and male identity. To date, however, theoretical attention to the social cognitive processes that regulate workplace harassment is scant. This article presents the development and preliminary validation of the Moral Disengagement in Sexual Harassment Scale (MDiSH); a self-report measure of moral disengagement in the context of hostile work environment harassment. Three studies (total n = 797) document the excellent psychometric properties of this new scale. Male U.K. university students (Study 1: n = 322) and U.S. working males (Studies 2 and 3: n = 475) completed the MDiSH and an array of measures for construct validation. The MDiSH exhibited positive correlations with sexual harassment myth acceptance, male gender identification, and hostile sexism. In Study 3, participants were exposed to a fictitious case of hostile work environment harassment. The MDiSH attenuated moral judgment, negative emotions (guilt, shame, and anger), sympathy, and endorsement of prosocial behavioral intentions (support for restitution) associated with the harassment case. Conversely, the MDiSH increased positive affect (happiness) about the harassment and attribution of blame to the female complainant. Implications for practice and future research avenues are discussed. © 2015 Wiley Periodicals, Inc.

A model of scientific attitudes assessment by observation in physics learning based scientific approach: case study of dynamic fluid topic in high school

NASA Astrophysics Data System (ADS)

Yusliana Ekawati, Elvin

2017-01-01

This study aimed to produce a model of scientific attitude assessment in terms of the observations for physics learning based scientific approach (case study of dynamic fluid topic in high school). Development of instruments in this study adaptation of the Plomp model, the procedure includes the initial investigation, design, construction, testing, evaluation and revision. The test is done in Surakarta, so that the data obtained are analyzed using Aiken formula to determine the validity of the content of the instrument, Cronbach’s alpha to determine the reliability of the instrument, and construct validity using confirmatory factor analysis with LISREL 8.50 program. The results of this research were conceptual models, instruments and guidelines on scientific attitudes assessment by observation. The construct assessment instruments include components of curiosity, objectivity, suspended judgment, open-mindedness, honesty and perseverance. The construct validity of instruments has been qualified (rated load factor > 0.3). The reliability of the model is quite good with the Alpha value 0.899 (> 0.7). The test showed that the model fits the theoretical models are supported by empirical data, namely p-value 0.315 (≥ 0.05), RMSEA 0.027 (≤ 0.08)

Serum proteomic profiling of major depressive disorder

PubMed Central

Bot, M; Chan, M K; Jansen, R; Lamers, F; Vogelzangs, N; Steiner, J; Leweke, F M; Rothermundt, M; Cooper, J; Bahn, S; Penninx, B W J H

2015-01-01

Much has still to be learned about the molecular mechanisms of depression. This study aims to gain insight into contributing mechanisms by identifying serum proteins related to major depressive disorder (MDD) in a large psychiatric cohort study. Our sample consisted of 1589 participants of the Netherlands Study of Depression and Anxiety, comprising 687 individuals with current MDD (cMDD), 482 individuals with remitted MDD (rMDD) and 420 controls. We studied the relationship between MDD status and the levels of 171 serum proteins detected on a multi-analyte profiling platform using adjusted linear regression models. Pooled analyses of two independent validation cohorts (totaling 78 MDD cases and 156 controls) was carried out to validate our top markers. Twenty-eight analytes differed significantly between cMDD cases and controls (P<0.05), whereas 10 partly overlapping markers differed significantly between rMDD cases and controls. Antidepressant medication use and comorbid anxiety status did not substantially impact on these findings. Sixteen of the cMDD-related markers had been assayed in the pooled validation cohorts, of which seven were associated with MDD. The analytes prominently associated with cMDD related to diverse cell communication and signal transduction processes (pancreatic polypeptide, macrophage migration inhibitory factor, ENRAGE, interleukin-1 receptor antagonist and tenascin-C), immune response (growth-regulated alpha protein) and protein metabolism (von Willebrand factor). Several proteins were implicated in depression. Changes were more prominent in cMDD, suggesting that molecular alterations in serum are associated with acute depression symptomatology. These findings may help to establish serum-based biomarkers of depression and could improve our understanding of its pathophysiology. PMID:26171980

A nonlinear self-similar solution to barotropic flow over rapidly varying topography

NASA Astrophysics Data System (ADS)

Ibanez, Ruy; Kuehl, Joseph

2016-11-01

Beginning from the Shallow Water Equations (SWE), a nonlinear self-similar analytic solution is derived for barotropic flow over rapidly varying topography. We study conditions relevant to the ocean slope where the flow is dominated by Earth's rotation and topography. Attention is paid to the northern Gulf of Mexico slope with application to pollutant dispersion and the Norwegian Coastal Current which sheds eddies into the Lofoten Basin that are believe to influence deep water formation. The solution is found to extend the topographic β-plume solution (Kuehl 2014, GRL) in two ways: 1) The solution is valid for intensifying jets. 2) The influence of nonlinear advection is included. The SWE are scaled to the case of a topographically controlled jet, then solved by introducing a similarity variable η = Cxy . The nonlinear solution, valid for topographies h =h0 - αxy3 , takes the form of the Lambert W Function for velocity. The linear solution, valid for topographies h =h0 - αxyγ , takes the form of the Error Function for transport. Kuehl's results considered the case - 1 <= γ < 1 which admits expanding jets, while the new result consider the case γ < - 1 which admits intensifying jets.

The SAFE-T assessment tool: derivation and validation of a web-based application for point-of-care evaluation of gastroenterology fellow performance in colonoscopy.

PubMed

Kumar, Navin L; Kugener, Guillaume; Perencevich, Molly L; Saltzman, John R

2018-01-01

Attending assessment is a critical part of endoscopic education for gastroenterology fellows. The aim of this study was to develop and validate a concise assessment tool to evaluate real-time fellow performance in colonoscopy administered via a web-based application. The Skill Assessment in Fellow Endoscopy Training (SAFE-T) tool was derived as a novel 5-question evaluation tool that captures both summative and formative feedback adapted into a web-based application. A prospective study of 15 gastroenterology fellows (5 fellows each from years 1 to 3 of training) was performed using the SAFE-T tool. An independent reviewer evaluated a subset of these procedures and completed the SAFE-T tool and Mayo Colonoscopy Skills Assessment Tool (MCSAT) for reliability testing. Twenty-six faculty completed 350 SAFE-T evaluations of the 15 fellows in the study. The mean SAFE-T overall score (year 1, 2.00; year 2, 3.84; year 3, 4.28) differentiated each sequential fellow year of training (P < .0001). The mean SAFE-T overall score decreased with increasing case complexity score, with straightforward cases compared with average cases (4.07 vs 3.50, P < .0001), and average cases compared with challenging cases (3.50 vs 3.08, P = .0134). In dual-observed procedures, the SAFE-T tool showed excellent inter-rater reliability with a kappa agreement statistic of 0.898 (P < .0001). Correlation of the SAFE-T overall score with the MCSAT overall hands-on and individual motor scores was excellent (each r > 0.90, P < .0001). We developed and validated the SAFE-T assessment tool, a concise and web-based means of assessing real-time gastroenterology fellow performance in colonoscopy. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

The 10/66 Dementia Research Group's fully operationalised DSM-IV dementia computerized diagnostic algorithm, compared with the 10/66 dementia algorithm and a clinician diagnosis: a population validation study

PubMed Central

Prince, Martin J; de Rodriguez, Juan Llibre; Noriega, L; Lopez, A; Acosta, Daisy; Albanese, Emiliano; Arizaga, Raul; Copeland, John RM; Dewey, Michael; Ferri, Cleusa P; Guerra, Mariella; Huang, Yueqin; Jacob, KS; Krishnamoorthy, ES; McKeigue, Paul; Sousa, Renata; Stewart, Robert J; Salas, Aquiles; Sosa, Ana Luisa; Uwakwa, Richard

2008-01-01

Background The criterion for dementia implicit in DSM-IV is widely used in research but not fully operationalised. The 10/66 Dementia Research Group sought to do this using assessments from their one phase dementia diagnostic research interview, and to validate the resulting algorithm in a population-based study in Cuba. Methods The criterion was operationalised as a computerised algorithm, applying clinical principles, based upon the 10/66 cognitive tests, clinical interview and informant reports; the Community Screening Instrument for Dementia, the CERAD 10 word list learning and animal naming tests, the Geriatric Mental State, and the History and Aetiology Schedule – Dementia Diagnosis and Subtype. This was validated in Cuba against a local clinician DSM-IV diagnosis and the 10/66 dementia diagnosis (originally calibrated probabilistically against clinician DSM-IV diagnoses in the 10/66 pilot study). Results The DSM-IV sub-criteria were plausibly distributed among clinically diagnosed dementia cases and controls. The clinician diagnoses agreed better with 10/66 dementia diagnosis than with the more conservative computerized DSM-IV algorithm. The DSM-IV algorithm was particularly likely to miss less severe dementia cases. Those with a 10/66 dementia diagnosis who did not meet the DSM-IV criterion were less cognitively and functionally impaired compared with the DSMIV confirmed cases, but still grossly impaired compared with those free of dementia. Conclusion The DSM-IV criterion, strictly applied, defines a narrow category of unambiguous dementia characterized by marked impairment. It may be specific but incompletely sensitive to clinically relevant cases. The 10/66 dementia diagnosis defines a broader category that may be more sensitive, identifying genuine cases beyond those defined by our DSM-IV algorithm, with relevance to the estimation of the population burden of this disorder. PMID:18577205

Assessing the generalizability of randomized trial results to target populations.

PubMed

Stuart, Elizabeth A; Bradshaw, Catherine P; Leaf, Philip J

2015-04-01

Recent years have seen increasing interest in and attention to evidence-based practices, where the "evidence" generally comes from well-conducted randomized trials. However, while those trials yield accurate estimates of the effect of the intervention for the participants in the trial (known as "internal validity"), they do not always yield relevant information about the effects in a particular target population (known as "external validity"). This may be due to a lack of specification of a target population when designing the trial, difficulties recruiting a sample that is representative of a prespecified target population, or to interest in considering a target population somewhat different from the population directly targeted by the trial. This paper first provides an overview of existing design and analysis methods for assessing and enhancing the ability of a randomized trial to estimate treatment effects in a target population. It then provides a case study using one particular method, which weights the subjects in a randomized trial to match the population on a set of observed characteristics. The case study uses data from a randomized trial of school-wide positive behavioral interventions and supports (PBIS); our interest is in generalizing the results to the state of Maryland. In the case of PBIS, after weighting, estimated effects in the target population were similar to those observed in the randomized trial. The paper illustrates that statistical methods can be used to assess and enhance the external validity of randomized trials, making the results more applicable to policy and clinical questions. However, there are also many open research questions; future research should focus on questions of treatment effect heterogeneity and further developing these methods for enhancing external validity. Researchers should think carefully about the external validity of randomized trials and be cautious about extrapolating results to specific populations unless they are confident of the similarity between the trial sample and that target population.

Validation of X1 motorcycle model in industrial plant layout by using WITNESSTM simulation software

NASA Astrophysics Data System (ADS)

Hamzas, M. F. M. A.; Bareduan, S. A.; Zakaria, M. Z.; Tan, W. J.; Zairi, S.

2017-09-01

This paper demonstrates a case study on simulation, modelling and analysis for X1 Motorcycles Model. In this research, a motorcycle assembly plant has been selected as a main place of research study. Simulation techniques by using Witness software were applied to evaluate the performance of the existing manufacturing system. The main objective is to validate the data and find out the significant impact on the overall performance of the system for future improvement. The process of validation starts when the layout of the assembly line was identified. All components are evaluated to validate whether the data is significance for future improvement. Machine and labor statistics are among the parameters that were evaluated for process improvement. Average total cycle time for given workstations is used as criterion for comparison of possible variants. From the simulation process, the data used are appropriate and meet the criteria for two-sided assembly line problems.

Measuring violence risk and outcomes among Mexican American adolescent females.

PubMed

Cervantes, Richard C; Duenas, Norma; Valdez, Avelardo; Kaplan, Charles

2006-01-01

Central to the development of culturally competent violence prevention programs for Hispanic youth is the development of psychometrically sound violence risk and outcome measures for this population. A study was conducted to determine the psychometric properties of two commonly used violence measures, in this case for Mexican American adolescent females. The Conflict Tactics Scales (CTS2) and the Past Feelings and Acts of Violence Scale (PFAV) were analyzed to examine their interitem reliability, criterion validity, and discriminant validity. A sample of 150 low-risk and 150 high-risk adolescent females was studied. Discriminant validity was indicated by the perpetrator negotiation scale and by the victim psychological aggression and sexual coercion scales of the CTS2 and the PFAV. Analysis indicates that the CTS2 scales and the PFAV demonstrate adequate reliability, whereas strong criterion validity was evidenced by eight of the CTS2 scales and the PFAV.

Operating room clinicians' ratings of workload: a vignette simulation study.

PubMed

Wallston, Kenneth A; Slagle, Jason M; Speroff, Ted; Nwosu, Sam; Crimin, Kimberly; Feurer, Irene D; Boettcher, Brent; Weinger, Matthew B

2014-06-01

Increased clinician workload is associated with medical errors and patient harm. The Quality and Workload Assessment Tool (QWAT) measures anticipated (pre-case) and perceived (post-case) clinical workload during actual surgical procedures using ratings of individual and team case difficulty from every operating room (OR) team member. The purpose of this study was to examine the QWAT ratings of OR clinicians who were not present in the OR but who read vignettes compiled from actual case documentation to assess interrater reliability and agreement with ratings made by clinicians involved in the actual cases. Thirty-six OR clinicians (13 anesthesia providers, 11 surgeons, and 12 nurses) used the QWAT to rate 6 cases varying from easy to moderately difficult based on actual ratings made by clinicians involved with the cases. Cases were presented and rated in random order. Before rating anticipated individual and team difficulty, the raters read prepared clinical vignettes containing case synopses and much of the same written case information that was available to the actual clinicians before the onset of each case. Then, before rating perceived individual and team difficulty, they read part 2 of the vignette consisting of detailed role-specific intraoperative data regarding the anesthetic and surgical course, unusual events, and other relevant contextual factors. Surgeons had higher interrater reliability on the QWAT than did OR nurses or anesthesia providers. For the anticipated individual and team workload ratings, there were no statistically significant differences between the actual ratings and the ratings obtained from the vignettes. There were differences for the 3 provider types in perceived individual workload for the median difficulty cases and in the perceived team workload for the median and more difficult cases. The case difficulty items on the QWAT seem to be sufficiently reliable and valid to be used in other studies of anticipated and perceived clinical workload of surgeons. Perhaps because of the limitations of the clinical documentation shown to anesthesia providers and OR nurses in the current vignette study, more evidence needs to be gathered to demonstrate the criterion-related validity of the QWAT difficulty items for assessing the workload of nonsurgeon OR clinicians.

Description of a Website Resource for Turbulence Modeling Verification and Validation

NASA Technical Reports Server (NTRS)

Rumsey, Christopher L.; Smith, Brian R.; Huang, George P.

2010-01-01

The activities of the Turbulence Model Benchmarking Working Group - which is a subcommittee of the American Institute of Aeronautics and Astronautics (AIAA) Fluid Dynamics Technical Committee - are described. The group s main purpose is to establish a web-based repository for Reynolds-averaged Navier-Stokes turbulence model documentation, including verification and validation cases. This turbulence modeling resource has been established based on feedback from a survey on what is needed to achieve consistency and repeatability in turbulence model implementation and usage, and to document and disseminate information on new turbulence models or improvements to existing models. The various components of the website are described in detail: description of turbulence models, turbulence model readiness rating system, verification cases, validation cases, validation databases, and turbulence manufactured solutions. An outline of future plans of the working group is also provided.

Molecular markers of carcinogenesis for risk stratification of individuals with colorectal polyps: a case-control study.

PubMed

Gupta, Samir; Sun, Han; Yi, Sang; Storm, Joy; Xiao, Guanghua; Balasubramanian, Bijal A; Zhang, Song; Ashfaq, Raheela; Rockey, Don C

2014-10-01

Risk stratification using number, size, and histology of colorectal adenomas is currently suboptimal for identifying patients at increased risk for future colorectal cancer. We hypothesized that molecular markers of carcinogenesis in adenomas, measured via immunohistochemistry, may help identify high-risk patients. To test this hypothesis, we conducted a retrospective, 1:1 matched case-control study (n = 216; 46% female) in which cases were patients with colorectal cancer and synchronous adenoma and controls were patients with adenoma but no colorectal cancer at baseline or within 5 years of follow-up. In phase I of analyses, we compared expression of molecular markers of carcinogenesis in case and control adenomas, blind to case status. In phase II of analyses, patients were randomly divided into independent training and validation groups to develop a model for predicting case status. We found that seven markers [p53, p21, Cox-2, β-catenin (BCAT), DNA-dependent protein kinase (DNApkcs), survivin, and O6-methylguanine-DNA methyltransferase (MGMT)] were significantly associated with case status on unadjusted analyses, as well as analyses adjusted for age and advanced adenoma status (P < 0.01 for at least one marker component). When applied to the validation set, a predictive model using these seven markers showed substantial accuracy for identifying cases [area under the receiver operation characteristic curve (AUC), 0.83; 95% confidence interval (CI), 0.74-0.92]. A parsimonious model using three markers performed similarly to the seven-marker model (AUC, 0.84). In summary, we found that molecular markers of carcinogenesis distinguished adenomas from patients with and without colorectal cancer. Furthermore, we speculate that prospective studies using molecular markers to identify individuals with polyps at risk for future neoplasia are warranted. ©2014 American Association for Cancer Research.

On the validity of the Arrhenius equation for electron attachment rate coefficients.

PubMed

Fabrikant, Ilya I; Hotop, Hartmut

2008-03-28

The validity of the Arrhenius equation for dissociative electron attachment rate coefficients is investigated. A general analysis allows us to obtain estimates of the upper temperature bound for the range of validity of the Arrhenius equation in the endothermic case and both lower and upper bounds in the exothermic case with a reaction barrier. The results of the general discussion are illustrated by numerical examples whereby the rate coefficient, as a function of temperature for dissociative electron attachment, is calculated using the resonance R-matrix theory. In the endothermic case, the activation energy in the Arrhenius equation is close to the threshold energy, whereas in the case of exothermic reactions with an intermediate barrier, the activation energy is found to be substantially lower than the barrier height.

The validity and reliability of diagnoses of work-related mental ill-health.

PubMed

O'Neill, E; McNamee, R; Agius, R; Gittins, M; Hussey, L; Turner, S

2008-11-01

To establish the reliability and validity of work-related mental ill-health diagnoses. A UK-based surveillance scheme for work-related ill-health involving occupational physicians (OPs) reporting suggests that mental ill-health incidence is increasing by around 13% per year, with anxiety, depression and "other work-related stress" being the most common diagnoses. There have been no studies of the validity and reliability of such diagnoses. Given the existence of a large network of psychiatrists (PSYs) also involved in surveillance of work-related ill-health, an opportunity arose to measure the concurrent validity and reliability of work-related mental ill-health diagnoses. 100 anonymised summaries of cases previously reported by OPs or PSYs were collected; each was sent to 5 PSYs and 5 OPs, who assigned a diagnosis and judged whether the case was work-related. Concurrent validity of the ill-health aspect of the diagnoses, and of the opinion as to work-relatedness, was assessed by comparing the overall classifications of cases by OPs and PSYs. Reliability of the diagnostic classification was measured by kappa matrices. Diagnostic proportions for PSYs and OPs demonstrated good agreement for anxiety, depression, anxiety plus depression and "stress" (11%, 34%, 27%, 14%) and (14%, 30%, 27%, 17%), respectively. In both groups, kappa coefficients were high for a psychotic diagnosis (0.78, 95% CI: 0.74 to 0.83), but not as high for anxiety (0.27, 95% CI: 0.23 to 0.32), depression (0.34, 95% CI: 0.29 to 0.38) and "stress" (0.15, 95% CI: 0.10 to 0.19). The odds ratio of classifying a case as work-related among PSYs compared to OPs was 2.39 (95% CI: 1.68 to 3.38), p<0.001. The overall agreement between OPs and PSYs on mental ill-health diagnoses suggests that OP diagnoses are valid for epidemiological purposes. However, the within-group reliability of the diagnosis "stress" is low. Given differences in judgements about work-relatedness, further research is needed to investigate this aspect of a diagnosis.

Finite-difference method Stokes solver (FDMSS) for 3D pore geometries: Software development, validation and case studies

NASA Astrophysics Data System (ADS)

Gerke, Kirill M.; Vasilyev, Roman V.; Khirevich, Siarhei; Collins, Daniel; Karsanina, Marina V.; Sizonenko, Timofey O.; Korost, Dmitry V.; Lamontagne, Sébastien; Mallants, Dirk

2018-05-01

Permeability is one of the fundamental properties of porous media and is required for large-scale Darcian fluid flow and mass transport models. Whilst permeability can be measured directly at a range of scales, there are increasing opportunities to evaluate permeability from pore-scale fluid flow simulations. We introduce the free software Finite-Difference Method Stokes Solver (FDMSS) that solves Stokes equation using a finite-difference method (FDM) directly on voxelized 3D pore geometries (i.e. without meshing). Based on explicit convergence studies, validation on sphere packings with analytically known permeabilities, and comparison against lattice-Boltzmann and other published FDM studies, we conclude that FDMSS provides a computationally efficient and accurate basis for single-phase pore-scale flow simulations. By implementing an efficient parallelization and code optimization scheme, permeability inferences can now be made from 3D images of up to 109 voxels using modern desktop computers. Case studies demonstrate the broad applicability of the FDMSS software for both natural and artificial porous media.

Circular instead of hierarchical: methodological principles for the evaluation of complex interventions

PubMed Central

Walach, Harald; Falkenberg, Torkel; Fønnebø, Vinjar; Lewith, George; Jonas, Wayne B

2006-01-01

Background The reasoning behind evaluating medical interventions is that a hierarchy of methods exists which successively produce improved and therefore more rigorous evidence based medicine upon which to make clinical decisions. At the foundation of this hierarchy are case studies, retrospective and prospective case series, followed by cohort studies with historical and concomitant non-randomized controls. Open-label randomized controlled studies (RCTs), and finally blinded, placebo-controlled RCTs, which offer most internal validity are considered the most reliable evidence. Rigorous RCTs remove bias. Evidence from RCTs forms the basis of meta-analyses and systematic reviews. This hierarchy, founded on a pharmacological model of therapy, is generalized to other interventions which may be complex and non-pharmacological (healing, acupuncture and surgery). Discussion The hierarchical model is valid for limited questions of efficacy, for instance for regulatory purposes and newly devised products and pharmacological preparations. It is inadequate for the evaluation of complex interventions such as physiotherapy, surgery and complementary and alternative medicine (CAM). This has to do with the essential tension between internal validity (rigor and the removal of bias) and external validity (generalizability). Summary Instead of an Evidence Hierarchy, we propose a Circular Model. This would imply a multiplicity of methods, using different designs, counterbalancing their individual strengths and weaknesses to arrive at pragmatic but equally rigorous evidence which would provide significant assistance in clinical and health systems innovation. Such evidence would better inform national health care technology assessment agencies and promote evidence based health reform. PMID:16796762

An Analytical Study on an Orthodontic Index: Index of Complexity, Outcome and Need (ICON)

PubMed Central

Torkan, Sepide; Pakshir, Hamid Reza; Fattahi, Hamid Reza; Oshagh, Morteza; Momeni Danaei, Shahla; Salehi, Parisa; Hedayati, Zohreh

2015-01-01

Statement of the Problem The validity of the Index of Complexity, Outcome and Need (ICON) which is an orthodontic index developed and introduced in 2000 should be studied in different ethnic groups. Purpose The aim of this study was to perform an analysis on the ICON and to verify whether this index is valid for assessing both the need and complexity of orthodontic treatment in Iran. Materials and Method Five orthodontists were asked to score pre-treatment diagnostic records of 100 patients with a uniform distribution of different types of malocclusions determined by Dental Health Component of the Index of Treatment Need. A calibrated examiner also assessed the need for orthodontic treatment and complexity of the cases based on the ICON index as well as the Index of Orthodontic Treatment Need (IOTN). 10 days later, 25% of the cases were re-scored by the panel of experts and the calibrated orthodontist. Results The weighted kappa revealed the inter-examiner reliability of the experts to be 0.63 and 0.51 for the need and complexity components, respectively. ROC curve was used to assess the validity of the index. A new cut-off point was adjusted at 35 in lieu of 43 as the suggested cut-off point. This cut-off point showed the highest level of sensitivity and specificity in our society for orthodontic treatment need (0.77 and 0.78, respectively), but it failed to define definite ranges for the complexity of treatment. Conclusion ICON is a valid index in assessing the need for treatment in Iran when the cut-off point is adjusted to 35. As for complexity of treatment, the index is not validated for our society. It seems that ICON is a well-suited substitute for the IOTN index. PMID:26331142

Validity of the coding for herpes simplex encephalitis in the Danish National Patient Registry

PubMed Central

Jørgensen, Laura Krogh; Dalgaard, Lars Skov; Østergaard, Lars Jørgen; Andersen, Nanna Skaarup; Nørgaard, Mette; Mogensen, Trine Hyrup

2016-01-01

Background Large health care databases are a valuable source of infectious disease epidemiology if diagnoses are valid. The aim of this study was to investigate the accuracy of the recorded diagnosis coding of herpes simplex encephalitis (HSE) in the Danish National Patient Registry (DNPR). Methods The DNPR was used to identify all hospitalized patients, aged ≥15 years, with a first-time diagnosis of HSE according to the International Classification of Diseases, tenth revision (ICD-10), from 2004 to 2014. To validate the coding of HSE, we collected data from the Danish Microbiology Database, from departments of clinical microbiology, and from patient medical records. Cases were classified as confirmed, probable, or no evidence of HSE. We estimated the positive predictive value (PPV) of the HSE diagnosis coding stratified by diagnosis type, study period, and department type. Furthermore, we estimated the proportion of HSE cases coded with nonspecific ICD-10 codes of viral encephalitis and also the sensitivity of the HSE diagnosis coding. Results We were able to validate 398 (94.3%) of the 422 HSE diagnoses identified via the DNPR. Hereof, 202 (50.8%) were classified as confirmed cases and 29 (7.3%) as probable cases providing an overall PPV of 58.0% (95% confidence interval [CI]: 53.0–62.9). For “Encephalitis due to herpes simplex virus” (ICD-10 code B00.4), the PPV was 56.6% (95% CI: 51.1–62.0). Similarly, the PPV for “Meningoencephalitis due to herpes simplex virus” (ICD-10 code B00.4A) was 56.8% (95% CI: 39.5–72.9). “Herpes viral encephalitis” (ICD-10 code G05.1E) had a PPV of 75.9% (95% CI: 56.5–89.7), thereby representing the highest PPV. The estimated sensitivity was 95.5%. Conclusion The PPVs of the ICD-10 diagnosis coding for adult HSE in the DNPR were relatively low. Hence, the DNPR should be used with caution when studying patients with encephalitis caused by herpes simplex virus. PMID:27330328

A Framework for Text Mining in Scientometric Study: A Case Study in Biomedicine Publications

NASA Astrophysics Data System (ADS)

Silalahi, V. M. M.; Hardiyati, R.; Nadhiroh, I. M.; Handayani, T.; Rahmaida, R.; Amelia, M.

2018-04-01

The data of Indonesians research publications in the domain of biomedicine has been collected to be text mined for the purpose of a scientometric study. The goal is to build a predictive model that provides a classification of research publications on the potency for downstreaming. The model is based on the drug development processes adapted from the literatures. An effort is described to build the conceptual model and the development of a corpus on the research publications in the domain of Indonesian biomedicine. Then an investigation is conducted relating to the problems associated with building a corpus and validating the model. Based on our experience, a framework is proposed to manage the scientometric study based on text mining. Our method shows the effectiveness of conducting a scientometric study based on text mining in order to get a valid classification model. This valid model is mainly supported by the iterative and close interactions with the domain experts starting from identifying the issues, building a conceptual model, to the labelling, validation and results interpretation.

External Validation of a Case-Mix Adjustment Model for the Standardized Reporting of 30-Day Stroke Mortality Rates in China.

PubMed

Yu, Ping; Pan, Yuesong; Wang, Yongjun; Wang, Xianwei; Liu, Liping; Ji, Ruijun; Meng, Xia; Jing, Jing; Tong, Xu; Guo, Li; Wang, Yilong

2016-01-01

A case-mix adjustment model has been developed and externally validated, demonstrating promise. However, the model has not been thoroughly tested among populations in China. In our study, we evaluated the performance of the model in Chinese patients with acute stroke. The case-mix adjustment model A includes items on age, presence of atrial fibrillation on admission, National Institutes of Health Stroke Severity Scale (NIHSS) score on admission, and stroke type. Model B is similar to Model A but includes only the consciousness component of the NIHSS score. Both model A and B were evaluated to predict 30-day mortality rates in 13,948 patients with acute stroke from the China National Stroke Registry. The discrimination of the models was quantified by c-statistic. Calibration was assessed using Pearson's correlation coefficient. The c-statistic of model A in our external validation cohort was 0.80 (95% confidence interval, 0.79-0.82), and the c-statistic of model B was 0.82 (95% confidence interval, 0.81-0.84). Excellent calibration was reported in the two models with Pearson's correlation coefficient (0.892 for model A, p<0.001; 0.927 for model B, p = 0.008). The case-mix adjustment model could be used to effectively predict 30-day mortality rates in Chinese patients with acute stroke.

TH-A-19A-11: Validation of GPU-Based Monte Carlo Code (gPMC) Versus Fully Implemented Monte Carlo Code (TOPAS) for Proton Radiation Therapy: Clinical Cases Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giantsoudi, D; Schuemann, J; Dowdell, S

Purpose: For proton radiation therapy, Monte Carlo simulation (MCS) methods are recognized as the gold-standard dose calculation approach. Although previously unrealistic due to limitations in available computing power, GPU-based applications allow MCS of proton treatment fields to be performed in routine clinical use, on time scales comparable to that of conventional pencil-beam algorithms. This study focuses on validating the results of our GPU-based code (gPMC) versus fully implemented proton therapy based MCS code (TOPAS) for clinical patient cases. Methods: Two treatment sites were selected to provide clinical cases for this study: head-and-neck cases due to anatomical geometrical complexity (air cavitiesmore » and density heterogeneities), making dose calculation very challenging, and prostate cases due to higher proton energies used and close proximity of the treatment target to sensitive organs at risk. Both gPMC and TOPAS methods were used to calculate 3-dimensional dose distributions for all patients in this study. Comparisons were performed based on target coverage indices (mean dose, V90 and D90) and gamma index distributions for 2% of the prescription dose and 2mm. Results: For seven out of eight studied cases, mean target dose, V90 and D90 differed less than 2% between TOPAS and gPMC dose distributions. Gamma index analysis for all prostate patients resulted in passing rate of more than 99% of voxels in the target. Four out of five head-neck-cases showed passing rate of gamma index for the target of more than 99%, the fifth having a gamma index passing rate of 93%. Conclusion: Our current work showed excellent agreement between our GPU-based MCS code and fully implemented proton therapy based MC code for a group of dosimetrically challenging patient cases.« less

Assessment of bachelor's theses in a nursing degree with a rubrics system: Development and validation study.

PubMed

González-Chordá, Víctor M; Mena-Tudela, Desirée; Salas-Medina, Pablo; Cervera-Gasch, Agueda; Orts-Cortés, Isabel; Maciá-Soler, Loreto

2016-02-01

Writing a bachelor thesis (BT) is the last step to obtain a nursing degree. In order to perform an effective assessment of a nursing BT, certain reliable and valid tools are required. To develop and validate a 3-rubric system (drafting process, dissertation, and viva) to assess final year nursing students' BT. A multi-disciplinary study of content validity and psychometric properties. The study was carried out between December 2014 and July 2015. Nursing Degree at Universitat Jaume I. Spain. Eleven experts (9 nursing professors and 2 education professors from 6 different universities) took part in the development and content validity stages. Fifty-two theses presented during the 2014-2015 academic year were included by consecutive sampling of cases in order to study the psychometric properties. First, a group of experts was created to validate the content of the assessment system based on three rubrics (drafting process, dissertation, and viva). Subsequently, a reliability and validity study of the rubrics was carried out on the 52 theses presented during the 2014-2015 academic year. The BT drafting process rubric has 8 criteria (S-CVI=0.93; α=0.837; ICC=0.614), the dissertation rubric has 7 criteria (S-CVI=0.9; α=0.893; ICC=0.74), and the viva rubric has 4 criteria (S-CVI=0.86; α=8.16; ICC=0.895). A nursing BT assessment system based on three rubrics (drafting process, dissertation, and viva) has been validated. This system may be transferred to other nursing degrees or degrees from other academic areas. It is necessary to continue with the validation process taking into account factors that may affect the results obtained. Copyright © 2015 Elsevier Ltd. All rights reserved.

Yang-Baxter deformations of W2,4 × T1,1 and the associated T-dual models

NASA Astrophysics Data System (ADS)

Sakamoto, Jun-ichi; Yoshida, Kentaroh

2017-08-01

Recently, for principal chiral models and symmetric coset sigma models, Hoare and Tseytlin proposed an interesting conjecture that the Yang-Baxter deformations with the homogeneous classical Yang-Baxter equation are equivalent to non-abelian T-dualities with topological terms. It is significant to examine this conjecture for non-symmetric (i.e., non-integrable) cases. Such an example is the W2,4 ×T 1 , 1 background. In this note, we study Yang-Baxter deformations of type IIB string theory defined on W2,4 ×T 1 , 1 and the associated T-dual models, and show that this conjecture is valid even for this case. Our result indicates that the conjecture would be valid beyond integrability.

Validity test and its consistency in the construction of patient loyalty model

NASA Astrophysics Data System (ADS)

Yanuar, Ferra

2016-04-01

The main objective of this present study is to demonstrate the estimation of validity values and its consistency based on structural equation model. The method of estimation was then implemented to an empirical data in case of the construction the patient loyalty model. In the hypothesis model, service quality, patient satisfaction and patient loyalty were determined simultaneously, each factor were measured by any indicator variables. The respondents involved in this study were the patients who ever got healthcare at Puskesmas in Padang, West Sumatera. All 394 respondents who had complete information were included in the analysis. This study found that each construct; service quality, patient satisfaction and patient loyalty were valid. It means that all hypothesized indicator variables were significant to measure their corresponding latent variable. Service quality is the most measured by tangible, patient satisfaction is the most mesured by satisfied on service and patient loyalty is the most measured by good service quality. Meanwhile in structural equation, this study found that patient loyalty was affected by patient satisfaction positively and directly. Service quality affected patient loyalty indirectly with patient satisfaction as mediator variable between both latent variables. Both structural equations were also valid. This study also proved that validity values which obtained here were also consistence based on simulation study using bootstrap approach.

Validation of sentinel lymph node biopsy in breast cancer women N1-N2 with complete axillary response after neoadjuvant chemotherapy. Multicentre study in Tarragona.

PubMed

Carrera, D; de la Flor, M; Galera, J; Amillano, K; Gomez, M; Izquierdo, V; Aguilar, E; López, S; Martínez, M; Martínez, S; Serra, J M; Pérez, M; Martin, L

2016-01-01

The aim of our study was to evaluate sentinel lymph node biopsy as a diagnostic test for assessing the presence of residual metastatic axillary lymph nodes after neoadjuvant chemotherapy, replacing the need for a lymphadenectomy in negative selective lymph node biopsy patients. A multicentre, diagnostic validation study was conducted in the province of Tarragona, on women with T1-T3, N1-N2 breast cancer, who presented with a complete axillary response after neoadjuvant chemotherapy. Study procedures consisted of performing an selective lymph node biopsy followed by lymphadenectomy. A total of 53 women were included in the study. Surgical detection rate was 90.5% (no sentinel node found in 5 patients). Histopathological analysis of the lymphadenectomy showed complete disease regression of axillary nodes in 35.4% (17/48) of the patients, and residual axillary node involvement in 64.6% (31/48) of them. In lymphadenectomy positive patients, 28 had a positive selective lymph node biopsy (true positive), while 3 had a negative selective lymph node biopsy (false negative). Of the 28 true selective lymph node biopsy positives, the sentinel node was the only positive node in 10 cases. All lymphadenectomy negative cases were selective lymph node biopsy negative. These data yield a sensitivity of 93.5%, a false negative rate of 9.7%, and a global test efficiency of 93.7%. Selective lymph node biopsy after chemotherapy in patients with a complete axillary response provides valid and reliable information regarding axillary status after neoadjuvant treatment, and might prevent lymphadenectomy in cases with negative selective lymph node biopsy. Copyright © 2016 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

Assessment of Some Atomization Models Used in Spray Calculations

NASA Technical Reports Server (NTRS)

Raju, M. S.; Bulzin, Dan

2011-01-01

The paper presents the results from a validation study undertaken as a part of the NASA s fundamental aeronautics initiative on high altitude emissions in order to assess the accuracy of several atomization models used in both non-superheat and superheat spray calculations. As a part of this investigation we have undertaken the validation based on four different cases to investigate the spray characteristics of (1) a flashing jet generated by the sudden release of pressurized R134A from cylindrical nozzle, (2) a liquid jet atomizing in a subsonic cross flow, (3) a Parker-Hannifin pressure swirl atomizer, and (4) a single-element Lean Direct Injector (LDI) combustor experiment. These cases were chosen because of their importance in some aerospace applications. The validation is based on some 3D and axisymmetric calculations involving both reacting and non-reacting sprays. In general, the predicted results provide reasonable agreement for both mean droplet sizes (D32) and average droplet velocities but mostly underestimate the droplets sizes in the inner radial region of a cylindrical jet.

A diagnostic model for chronic hypersensitivity pneumonitis

PubMed Central

Johannson, Kerri A; Elicker, Brett M; Vittinghoff, Eric; Assayag, Deborah; de Boer, Kaïssa; Golden, Jeffrey A; Jones, Kirk D; King, Talmadge E; Koth, Laura L; Lee, Joyce S; Ley, Brett; Wolters, Paul J; Collard, Harold R

2017-01-01

The objective of this study was to develop a diagnostic model that allows for a highly specific diagnosis of chronic hypersensitivity pneumonitis using clinical and radiological variables alone. Chronic hypersensitivity pneumonitis and other interstitial lung disease cases were retrospectively identified from a longitudinal database. High-resolution CT scans were blindly scored for radiographic features (eg, ground-glass opacity, mosaic perfusion) as well as the radiologist’s diagnostic impression. Candidate models were developed then evaluated using clinical and radiographic variables and assessed by the cross-validated C-statistic. Forty-four chronic hypersensitivity pneumonitis and eighty other interstitial lung disease cases were identified. Two models were selected based on their statistical performance, clinical applicability and face validity. Key model variables included age, down feather and/or bird exposure, radiographic presence of ground-glass opacity and mosaic perfusion and moderate or high confidence in the radiographic impression of chronic hypersensitivity pneumonitis. Models were internally validated with good performance, and cut-off values were established that resulted in high specificity for a diagnosis of chronic hypersensitivity pneumonitis. PMID:27245779

Supportive decision making at the point of care: refinement of a case-based reasoning application for use in nursing practice.

PubMed

DI Pietro, Tammie L; Doran, Diane M; McArthur, Gregory

2010-01-01

Variations in nursing care have been observed, affecting patient outcomes and quality of care. Case-based reasoners that benchmark for patient indicators can reduce variation through decision support. This study evaluated and validated a case-based reasoning application to establish benchmarks for nursing-sensitive patient outcomes of pain, fatigue, and toilet use, using patient characteristic variables for generating similar cases. Three graduate nursing students participated. Each ranked 25 patient cases using demographics of age, sex, diagnosis, and comorbidities against 10 patients from a database. Participant judgments of case similarity were compared with the case-based reasoning system. Feature weights for each indicator were adjusted to make the case-based reasoning system's similarity ranking correspond more closely to participant judgment. Small differences were noted between initial weights and weights generated from participants. For example, initial weight for comorbidities was 0.35, whereas weights generated by participants for pain, fatigue, and toilet use were 0.49, 0.42, and 0.48, respectively. For the same outcomes, the initial weight for sex was 0.15, but weights generated by the participants were 0.025, 0.002, and 0.000, respectively. Refinement of the case-based reasoning tool established valid benchmarks for patient outcomes in relation to participants and assisted in point-of-care decision making.

Are Validity and Reliability "Relevant" in Qualitative Evaluation Research?

ERIC Educational Resources Information Center

Goodwin, Laura D.; Goodwin, William L.

1984-01-01

The views of prominant qualitative methodologists on the appropriateness of validity and reliability estimation for the measurement strategies employed in qualitative evaluations are summarized. A case is made for the relevance of validity and reliability estimation. Definitions of validity and reliability for qualitative measurement are presented…

Multilingual Validation of the Questionnaire for Verifying Stroke-Free Status in West Africa

PubMed Central

Sarfo, Fred; Gebregziabher, Mulugeta; Ovbiagele, Bruce; Akinyemi, Rufus; Owolabi, Lukman; Obiako, Reginald; Akpa, Onoja; Armstrong, Kevin; Akpalu, Albert; Adamu, Sheila; Obese, Vida; Boa-Antwi, Nana; Appiah, Lambert; Arulogun, Oyedunni; Mensah, Yaw; Adeoye, Abiodun; Tosin, Aridegbe; Adeleye, Osimhiarherhuo; Tabi-Ajayi, Eric; Phillip, Ibinaiye; Sani, Abubakar; Isah, Suleiman; Tabari, Nasir; Mande, Aliyu; Agunloye, Atinuke; Ogbole, Godwin; Akinyemi, Joshua; Laryea, Ruth; Melikam, Sylvia; Uvere, Ezinne; Adekunle, Gregory; Kehinde, Salaam; Azuh, Paschal; Dambatta, Abdul; Ishaq, Naser; Saulson, Raelle; Arnett, Donna; Tiwari, Hemnant; Jenkins, Carolyn; Lackland, Dan; Owolabi, Mayowa

2015-01-01

Background and Purpose The Questionnaire for Verifying Stroke-free Status (QVSFS), a method for verifying stroke-free status in participants of clinical, epidemiological and genetic studies, has not been validated in low-income settings where populations have limited knowledge of stroke symptoms. We aimed to validate QVSFS in 3 languages-Yoruba, Hausa and Akan- for ascertainment of stroke-free status of control subjects enrolled in an ongoing stroke epidemiological study in West Africa. Methods Data were collected using a cross-sectional study design where 384 participants were consecutively recruited from neurology and general medicine clinics of 5 tertiary referral hospitals in Nigeria and Ghana. Ascertainment of stroke status was by neurologists using structured neurological examination, review of case records and neuro-imaging (Gold standard). Relative performance of QVSFS without and with pictures of stroke symptoms (pictograms) was assessed using sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results The overall median age of the study participants was 54 years and 48.4% were males. Of 165 stroke cases identified by Gold standard, 98% were determined to have had stroke while of 219 without stroke 87% were determined to be stroke-free by QVSFS. NPV of the QVSFS across the 3 languages was 0.97 (range, 0.93 – 1.00), sensitivity, specificity and PPV were 0.98, 0.82 and 0.80 respectively. Agreement between the questionnaire with and without the pictogram was excellent/strong with Cohen’s k=0.92. Conclusions QVSFS is a valid tool for verifying stroke-free status across culturally diverse populations in West Africa. PMID:26578660

Multilingual Validation of the Questionnaire for Verifying Stroke-Free Status in West Africa.

PubMed

Sarfo, Fred; Gebregziabher, Mulugeta; Ovbiagele, Bruce; Akinyemi, Rufus; Owolabi, Lukman; Obiako, Reginald; Akpa, Onoja; Armstrong, Kevin; Akpalu, Albert; Adamu, Sheila; Obese, Vida; Boa-Antwi, Nana; Appiah, Lambert; Arulogun, Oyedunni; Mensah, Yaw; Adeoye, Abiodun; Tosin, Aridegbe; Adeleye, Osimhiarherhuo; Tabi-Ajayi, Eric; Phillip, Ibinaiye; Sani, Abubakar; Isah, Suleiman; Tabari, Nasir; Mande, Aliyu; Agunloye, Atinuke; Ogbole, Godwin; Akinyemi, Joshua; Laryea, Ruth; Melikam, Sylvia; Uvere, Ezinne; Adekunle, Gregory; Kehinde, Salaam; Azuh, Paschal; Dambatta, Abdul; Ishaq, Naser; Saulson, Raelle; Arnett, Donna; Tiwari, Hemnant; Jenkins, Carolyn; Lackland, Dan; Owolabi, Mayowa

2016-01-01

The Questionnaire for Verifying Stroke-Free Status (QVSFS), a method for verifying stroke-free status in participants of clinical, epidemiological, and genetic studies, has not been validated in low-income settings where populations have limited knowledge of stroke symptoms. We aimed to validate QVSFS in 3 languages, Yoruba, Hausa and Akan, for ascertainment of stroke-free status of control subjects enrolled in an on-going stroke epidemiological study in West Africa. Data were collected using a cross-sectional study design where 384 participants were consecutively recruited from neurology and general medicine clinics of 5 tertiary referral hospitals in Nigeria and Ghana. Ascertainment of stroke status was by neurologists using structured neurological examination, review of case records, and neuroimaging (gold standard). Relative performance of QVSFS without and with pictures of stroke symptoms (pictograms) was assessed using sensitivity, specificity, positive predictive value, and negative predictive value. The overall median age of the study participants was 54 years and 48.4% were males. Of 165 stroke cases identified by gold standard, 98% were determined to have had stroke, whereas of 219 without stroke 87% were determined to be stroke-free by QVSFS. Negative predictive value of the QVSFS across the 3 languages was 0.97 (range, 0.93-1.00), sensitivity, specificity, and positive predictive value were 0.98, 0.82, and 0.80, respectively. Agreement between the questionnaire with and without the pictogram was excellent/strong with Cohen k=0.92. QVSFS is a valid tool for verifying stroke-free status across culturally diverse populations in West Africa. © 2015 American Heart Association, Inc.

Advancing Our Understanding of the Etiologies and Mutational Landscapes of Basal-Like, Luminal A, and Luminal B Breast Cancers

DTIC Science & Technology

2014-10-01

supervision, the study coordinator, Ms. Taylor, will oversee the training of the study’s field and random digit dialing (RDD) interviewers. To support this...cases can be distinguished from each other. All triple-negative cases will be evaluated for EGFR and cytokeratin 5/6 using IHC so basal-like cases...be validated by PCR amplification of the identified exons in tumor and matched normal DNA followed by PCR cleanup using Agencourt Ampure XP reagents

Military Justice Study Guide

DTIC Science & Technology

1990-07-01

Intrusions for valid medical purposes 4-20 G. Inspections and inventories 4-21 1. General considerations 4-21 2. Inspections 4-21 3. Inventories 4-23...4-25 4. Valid medical purpose 4-25 5. Fitness-for-duty testing 4-26 a. Command-directPd testing 4-26 b. Aftercare and surveillance testing 4-26 c...that the convening authority assign a medical , scientific or other expert to assist in the preparation of the defense case. Once assigned, the expert

A Global Lake Ecological Observatory Network (GLEON) for synthesising high-frequency sensor data for validation of deterministic ecological models

USGS Publications Warehouse

David, Hamilton P; Carey, Cayelan C.; Arvola, Lauri; Arzberger, Peter; Brewer, Carol A.; Cole, Jon J; Gaiser, Evelyn; Hanson, Paul C.; Ibelings, Bas W; Jennings, Eleanor; Kratz, Tim K; Lin, Fang-Pang; McBride, Christopher G.; de Motta Marques, David; Muraoka, Kohji; Nishri, Ami; Qin, Boqiang; Read, Jordan S.; Rose, Kevin C.; Ryder, Elizabeth; Weathers, Kathleen C.; Zhu, Guangwei; Trolle, Dennis; Brookes, Justin D

2014-01-01

A Global Lake Ecological Observatory Network (GLEON; www.gleon.org) has formed to provide a coordinated response to the need for scientific understanding of lake processes, utilising technological advances available from autonomous sensors. The organisation embraces a grassroots approach to engage researchers from varying disciplines, sites spanning geographic and ecological gradients, and novel sensor and cyberinfrastructure to synthesise high-frequency lake data at scales ranging from local to global. The high-frequency data provide a platform to rigorously validate process- based ecological models because model simulation time steps are better aligned with sensor measurements than with lower-frequency, manual samples. Two case studies from Trout Bog, Wisconsin, USA, and Lake Rotoehu, North Island, New Zealand, are presented to demonstrate that in the past, ecological model outputs (e.g., temperature, chlorophyll) have been relatively poorly validated based on a limited number of directly comparable measurements, both in time and space. The case studies demonstrate some of the difficulties of mapping sensor measurements directly to model state variable outputs as well as the opportunities to use deviations between sensor measurements and model simulations to better inform process understanding. Well-validated ecological models provide a mechanism to extrapolate high-frequency sensor data in space and time, thereby potentially creating a fully 3-dimensional simulation of key variables of interest.

Empirical evaluation demonstrated importance of validating biomarkers for early detection of cancer in screening settings to limit the number of false-positive findings.

PubMed

Chen, Hongda; Knebel, Phillip; Brenner, Hermann

2016-07-01

Search for biomarkers for early detection of cancer is a very active area of research, but most studies are done in clinical rather than screening settings. We aimed to empirically evaluate the role of study setting for early detection marker identification and validation. A panel of 92 candidate cancer protein markers was measured in 35 clinically identified colorectal cancer patients and 35 colorectal cancer patients identified at screening colonoscopy. For each case group, we selected 38 controls without colorectal neoplasms at screening colonoscopy. Single-, two- and three-marker combinations discriminating cases and controls were identified in each setting and subsequently validated in the alternative setting. In all scenarios, a higher number of predictive biomarkers were initially detected in the clinical setting, but a substantially lower proportion of identified biomarkers could subsequently be confirmed in the screening setting. Confirmation rates were 50.0%, 84.5%, and 74.2% for one-, two-, and three-marker algorithms identified in the screening setting and were 42.9%, 18.6%, and 25.7% for algorithms identified in the clinical setting. Validation of early detection markers of cancer in a true screening setting is important to limit the number of false-positive findings. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Design and Technical Validation of a Telemedicine Service for Rural Healthcare in Ecuador.

PubMed

Vasquez-Cevallos, Leonel A; Bobokova, Jana; González-Granda, Patricia V; Iniesta, José M; Gómez, Enrique J; Hernando, M Elena

2017-12-12

Telemedicine is becoming increasingly important in Ecuador, especially in areas such as rural primary healthcare and medical education. Rural telemedicine programs in the country need to be strengthened by means of a technological platform adapted to local surroundings and offering advantages such as access to specialized care, continuing education, and so on, combined with modest investment requirements. This present article presents the design of a Telemedicine Platform (TMP) for rural healthcare services in Ecuador and a preliminary technical validation with medical students and teachers. An initial field study was designed to capture the requirements of the TMP. In a second phase, the TMP was validated in an academic environment along three consecutive academic courses. Assessment was by means of user polls and analyzing user interactions as registered automatically by the platform. The TMP was developed using Web-based technology and open code software. One hundred twenty-four students and 6 specialized faculty members participated in the study, conducting a total of 262 teleconsultations of clinical cases and 226 responses, respectively. The validation results show that the TMP is a useful communication tool for the documentation and discussion of clinical cases. Moreover, its usage may be recommended as a teaching methodology, to strengthen the skills of medical undergraduates. The results indicate that implementing the system in rural healthcare services in Ecuador would be feasible.

Advanced forensic validation for human spermatozoa identification using SPERM HY-LITER™ Express with quantitative image analysis.

PubMed

Takamura, Ayari; Watanabe, Ken; Akutsu, Tomoko

2017-07-01

Identification of human semen is indispensable for the investigation of sexual assaults. Fluorescence staining methods using commercial kits, such as the series of SPERM HY-LITER™ kits, have been useful to detect human sperm via strong fluorescence. These kits have been examined from various forensic aspects. However, because of a lack of evaluation methods, these studies did not provide objective, or quantitative, descriptions of the results nor clear criteria for the decisions reached. In addition, the variety of validations was considerably limited. In this study, we conducted more advanced validations of SPERM HY-LITER™ Express using our established image analysis method. Use of this method enabled objective and specific identification of fluorescent sperm's spots and quantitative comparisons of the sperm detection performance under complex experimental conditions. For body fluid mixtures, we examined interference with the fluorescence staining from other body fluid components. Effects of sample decomposition were simulated in high humidity and high temperature conditions. Semen with quite low sperm concentrations, such as azoospermia and oligospermia samples, represented the most challenging cases in application of the kit. Finally, the tolerance of the kit against various acidic and basic environments was analyzed. The validations herein provide useful information for the practical applications of the SPERM HY-LITER™ Express kit, which were previously unobtainable. Moreover, the versatility of our image analysis method toward various complex cases was demonstrated.

Development and validation of case-finding algorithms for the identification of patients with anti-neutrophil cytoplasmic antibody-associated vasculitis in large healthcare administrative databases.

PubMed

Sreih, Antoine G; Annapureddy, Narender; Springer, Jason; Casey, George; Byram, Kevin; Cruz, Andy; Estephan, Maya; Frangiosa, Vince; George, Michael D; Liu, Mei; Parker, Adam; Sangani, Sapna; Sharim, Rebecca; Merkel, Peter A

2016-12-01

The aim of this study was to develop and validate case-finding algorithms for granulomatosis with polyangiitis (Wegener's, GPA), microscopic polyangiitis (MPA), and eosinophilic GPA (Churg-Strauss, EGPA). Two hundred fifty patients per disease were randomly selected from two large healthcare systems using the International Classification of Diseases version 9 (ICD9) codes for GPA/EGPA (446.4) and MPA (446.0). Sixteen case-finding algorithms were constructed using a combination of ICD9 code, encounter type (inpatient or outpatient), physician specialty, use of immunosuppressive medications, and the anti-neutrophil cytoplasmic antibody type. Algorithms with the highest average positive predictive value (PPV) were validated in a third healthcare system. An algorithm excluding patients with eosinophilia or asthma and including the encounter type and physician specialty had the highest PPV for GPA (92.4%). An algorithm including patients with eosinophilia and asthma and the physician specialty had the highest PPV for EGPA (100%). An algorithm including patients with one of the diagnoses (alveolar hemorrhage, interstitial lung disease, glomerulonephritis, and acute or chronic kidney disease), encounter type, physician specialty, and immunosuppressive medications had the highest PPV for MPA (76.2%). When validated in a third healthcare system, these algorithms had high PPV (85.9% for GPA, 85.7% for EGPA, and 61.5% for MPA). Adding the anti-neutrophil cytoplasmic antibody type increased the PPV to 94.4%, 100%, and 81.2% for GPA, EGPA, and MPA, respectively. Case-finding algorithms accurately identify patients with GPA, EGPA, and MPA in administrative databases. These algorithms can be used to assemble population-based cohorts and facilitate future research in epidemiology, drug safety, and comparative effectiveness. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The reticulin algorithm for adrenocortical tumor diagnosis: a multicentric validation study on 245 unpublished cases.

PubMed

Duregon, Eleonora; Fassina, Ambrogio; Volante, Marco; Nesi, Gabriella; Santi, Raffaella; Gatti, Gaia; Cappellesso, Rocco; Dalino Ciaramella, Paolo; Ventura, Laura; Gambacorta, Marcello; Dei Tos, Angelo Paolo; Loli, Paola; Mannelli, Massimo; Mantero, Franco; Berruti, Alfredo; Terzolo, Massimo; Papotti, Mauro

2013-09-01

The pathologic diagnosis of adrenocortical carcinoma (ACC) still needs to be improved, because the renowned Weiss Score (WS) system has a poor reproducibility of some parameters and is difficult to apply in borderline cases and in ACC variants. The "reticulin algorithm" (RA) defines malignancy through an altered reticulin framework associated with 1 of the 3 following parameter: necrosis, high mitotic rate, and vascular invasion. This study aimed at validating the interobserver reproducibility of reticulin stain evaluation in an unpublished series of 245 adrenocortical tumors (61 adenomas and 184 carcinomas) from 5 Italian centers, classified according to the WS. Eight pathologists reviewed all reticulin-stained slides. After training, a second round of evaluation on discordant cases was performed 10 weeks later. The RA reclassified 67 cases (27%) as adenomas, including 44 with no reticulin alterations and 23 with an altered reticulin framework but lacking the subsequent parameters of the triad. The other 178 cases (73%) were carcinomas according to the above-mentioned criteria. A complete (8/8 pathologists) interobserver agreement was reached in 75% of cases (κ=0.702), irrespective of case derivation, pathologists' experience, and histologic variants, and was further improved when only those cases with high WS and clinically malignant behavior were considered. After the training, the overall agreement increased to 86%. We conclude that reticulin staining is a reliable technique and an easy-to-interpret system in adrenocortical tumors; moreover, it has a high interobserver reproducibility, which supports the notion of using such a method in the proposed 2-step RA approach for ACC diagnosis.

Validity of ICD-9-CM codes for breast, lung and colorectal cancers in three Italian administrative healthcare databases: a diagnostic accuracy study protocol.

PubMed

Abraha, Iosief; Serraino, Diego; Giovannini, Gianni; Stracci, Fabrizio; Casucci, Paola; Alessandrini, Giuliana; Bidoli, Ettore; Chiari, Rita; Cirocchi, Roberto; De Giorgi, Marcello; Franchini, David; Vitale, Maria Francesca; Fusco, Mario; Montedori, Alessandro

2016-03-25

Administrative healthcare databases are useful tools to study healthcare outcomes and to monitor the health status of a population. Patients with cancer can be identified through disease-specific codes, prescriptions and physician claims, but prior validation is required to achieve an accurate case definition. The objective of this protocol is to assess the accuracy of International Classification of Diseases Ninth Revision-Clinical Modification (ICD-9-CM) codes for breast, lung and colorectal cancers in identifying patients diagnosed with the relative disease in three Italian administrative databases. Data from the administrative databases of Umbria Region (910,000 residents), Local Health Unit 3 of Napoli (1,170,000 residents) and Friuli--Venezia Giulia Region (1,227,000 residents) will be considered. In each administrative database, patients with the first occurrence of diagnosis of breast, lung or colorectal cancer between 2012 and 2014 will be identified using the following groups of ICD-9-CM codes in primary position: (1) 233.0 and (2) 174.x for breast cancer; (3) 162.x for lung cancer; (4) 153.x for colon cancer and (5) 154.0-154.1 and 154.8 for rectal cancer. Only incident cases will be considered, that is, excluding cases that have the same diagnosis in the 5 years (2007-2011) before the period of interest. A random sample of cases and non-cases will be selected from each administrative database and the corresponding medical charts will be assessed for validation by pairs of trained, independent reviewers. Case ascertainment within the medical charts will be based on (1) the presence of a primary nodular lesion in the breast, lung or colon-rectum, documented with imaging or endoscopy and (2) a cytological or histological documentation of cancer from a primary or metastatic site. Sensitivity and specificity with 95% CIs will be calculated. Study results will be disseminated widely through peer-reviewed publications and presentations at national and international conferences. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

SeaWiFS Technical Report Series. Volume 41; Case Studies for SeaWiFS Calibration and Validation

NASA Technical Reports Server (NTRS)

Yeh, Eueng-nan; Barnes, Robert A.; Darzi, Michael; Kumar, Lakshmi; Early, Edward A.; Johnson, B. Carol; Mueller, James L.; Trees, Charles C.

1997-01-01

This document provides brief reports, or case studies, on a number of investigations sponsored by the Calibration and Validation Team (CVT) within the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Project. Chapter I describes the calibration and characterization of the GSFC sphere, which was used in the recent recalibration of the SeaWiFS instrument. Chapter 2 presents a revision of the diffuse attenuation coefficient, K(490), algorithm based on the SeaWiFS wavelengths. Chapter 3 provides an implementation scheme for an algorithm to remove out-of-band radiance when using a sensor calibration based on a finite width (truncated) spectral response function, e.g., between the 1% transmission points. Chapter 4 describes the implementation schemes for the stray light quality flag (local area coverage [LAC] and global area coverage [GAC]) and the LAC stray light correction.

A multisensor approach to sea ice classification for the validation of DMSP-SSM/I passive microwave derived sea ice products

NASA Technical Reports Server (NTRS)

Steffen, K.; Schweiger, A. J.

1990-01-01

The validation of sea ice products derived from the Special Sensor Microwave Imager (SSM/I) on board a DMSP platform is examined using data from the Landsat MSS and NOAA-AVHRR sensors. Image processing techniques for retrieving ice concentrations from each type of imagery are developed and results are intercompared to determine the ice parameter retrieval accuracy of the SSM/I NASA-Team algorithm. For case studies in the Beaufort Sea and East Greenland Sea, average retrieval errors of the SSM/I algorithm are between 1.7 percent for spring conditions and 4.3 percent during freeze up in comparison with Landsat derived ice concentrations. For a case study in the East Greenland Sea, SSM/I derived ice concentration in comparison with AVHRR imagery display a mean error of 9.6 percent.

Variation between Hospitals with Regard to Diagnostic Practice, Coding Accuracy, and Case-Mix. A Retrospective Validation Study of Administrative Data versus Medical Records for Estimating 30-Day Mortality after Hip Fracture.

PubMed

Helgeland, Jon; Kristoffersen, Doris Tove; Skyrud, Katrine Damgaard; Lindman, Anja Schou

2016-01-01

The purpose of this study was to assess the validity of patient administrative data (PAS) for calculating 30-day mortality after hip fracture as a quality indicator, by a retrospective study of medical records. We used PAS data from all Norwegian hospitals (2005-2009), merged with vital status from the National Registry, to calculate 30-day case-mix adjusted mortality for each hospital (n = 51). We used stratified sampling to establish a representative sample of both hospitals and cases. The hospitals were stratified according to high, low and medium mortality of which 4, 3, and 5 hospitals were sampled, respectively. Within hospitals, cases were sampled stratified according to year of admission, age, length of stay, and vital 30-day status (alive/dead). The final study sample included 1043 cases from 11 hospitals. Clinical information was abstracted from the medical records. Diagnostic and clinical information from the medical records and PAS were used to define definite and probable hip fracture. We used logistic regression analysis in order to estimate systematic between-hospital variation in unmeasured confounding. Finally, to study the consequences of unmeasured confounding for identifying mortality outlier hospitals, a sensitivity analysis was performed. The estimated overall positive predictive value was 95.9% for definite and 99.7% for definite or probable hip fracture, with no statistically significant differences between hospitals. The standard deviation of the additional, systematic hospital bias in mortality estimates was 0.044 on the logistic scale. The effect of unmeasured confounding on outlier detection was small to moderate, noticeable only for large hospital volumes. This study showed that PAS data are adequate for identifying cases of hip fracture, and the effect of unmeasured case mix variation was small. In conclusion, PAS data are adequate for calculating 30-day mortality after hip-fracture as a quality indicator in Norway.

Computational assessment of hemodynamics-based diagnostic tools using a database of virtual subjects: Application to three case studies.

PubMed

Willemet, Marie; Vennin, Samuel; Alastruey, Jordi

2016-12-08

Many physiological indexes and algorithms based on pulse wave analysis have been suggested in order to better assess cardiovascular function. Because these tools are often computed from in-vivo hemodynamic measurements, their validation is time-consuming, challenging, and biased by measurement errors. Recently, a new methodology has been suggested to assess theoretically these computed tools: a database of virtual subjects generated using numerical 1D-0D modeling of arterial hemodynamics. The generated set of simulations encloses a wide selection of healthy cases that could be encountered in a clinical study. We applied this new methodology to three different case studies that demonstrate the potential of our new tool, and illustrated each of them with a clinically relevant example: (i) we assessed the accuracy of indexes estimating pulse wave velocity; (ii) we validated and refined an algorithm that computes central blood pressure; and (iii) we investigated theoretical mechanisms behind the augmentation index. Our database of virtual subjects is a new tool to assist the clinician: it provides insight into the physical mechanisms underlying the correlations observed in clinical practice. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Can species distribution models really predict the expansion of invasive species?

PubMed Central

Rome, Quentin; Villemant, Claire; Courchamp, Franck

2018-01-01

Predictive studies are of paramount importance for biological invasions, one of the biggest threats for biodiversity. To help and better prioritize management strategies, species distribution models (SDMs) are often used to predict the potential invasive range of introduced species. Yet, SDMs have been regularly criticized, due to several strong limitations, such as violating the equilibrium assumption during the invasion process. Unfortunately, validation studies–with independent data–are too scarce to assess the predictive accuracy of SDMs in invasion biology. Yet, biological invasions allow to test SDMs usefulness, by retrospectively assessing whether they would have accurately predicted the latest ranges of invasion. Here, we assess the predictive accuracy of SDMs in predicting the expansion of invasive species. We used temporal occurrence data for the Asian hornet Vespa velutina nigrithorax, a species native to China that is invading Europe with a very fast rate. Specifically, we compared occurrence data from the last stage of invasion (independent validation points) to the climate suitability distribution predicted from models calibrated with data from the early stage of invasion. Despite the invasive species not being at equilibrium yet, the predicted climate suitability of validation points was high. SDMs can thus adequately predict the spread of V. v. nigrithorax, which appears to be—at least partially–climatically driven. In the case of V. v. nigrithorax, SDMs predictive accuracy was slightly but significantly better when models were calibrated with invasive data only, excluding native data. Although more validation studies for other invasion cases are needed to generalize our results, our findings are an important step towards validating the use of SDMs in invasion biology. PMID:29509789

Developing and validating a model to predict the success of an IHCS implementation: the Readiness for Implementation Model.

PubMed

Wen, Kuang-Yi; Gustafson, David H; Hawkins, Robert P; Brennan, Patricia F; Dinauer, Susan; Johnson, Pauley R; Siegler, Tracy

2010-01-01

To develop and validate the Readiness for Implementation Model (RIM). This model predicts a healthcare organization's potential for success in implementing an interactive health communication system (IHCS). The model consists of seven weighted factors, with each factor containing five to seven elements. Two decision-analytic approaches, self-explicated and conjoint analysis, were used to measure the weights of the RIM with a sample of 410 experts. The RIM model with weights was then validated in a prospective study of 25 IHCS implementation cases. Orthogonal main effects design was used to develop 700 conjoint-analysis profiles, which varied on seven factors. Each of the 410 experts rated the importance and desirability of the factors and their levels, as well as a set of 10 different profiles. For the prospective 25-case validation, three time-repeated measures of the RIM scores were collected for comparison with the implementation outcomes. Two of the seven factors, 'organizational motivation' and 'meeting user needs,' were found to be most important in predicting implementation readiness. No statistically significant difference was found in the predictive validity of the two approaches (self-explicated and conjoint analysis). The RIM was a better predictor for the 1-year implementation outcome than the half-year outcome. The expert sample, the order of the survey tasks, the additive model, and basing the RIM cut-off score on experience are possible limitations of the study. The RIM needs to be empirically evaluated in institutions adopting IHCS and sustaining the system in the long term.

Validation of Case Finding Algorithms for Hepatocellular Cancer from Administrative Data and Electronic Health Records using Natural Language Processing

PubMed Central

Sada, Yvonne; Hou, Jason; Richardson, Peter; El-Serag, Hashem; Davila, Jessica

2013-01-01

Background Accurate identification of hepatocellular cancer (HCC) cases from automated data is needed for efficient and valid quality improvement initiatives and research. We validated HCC ICD-9 codes, and evaluated whether natural language processing (NLP) by the Automated Retrieval Console (ARC) for document classification improves HCC identification. Methods We identified a cohort of patients with ICD-9 codes for HCC during 2005–2010 from Veterans Affairs administrative data. Pathology and radiology reports were reviewed to confirm HCC. The positive predictive value (PPV), sensitivity, and specificity of ICD-9 codes were calculated. A split validation study of pathology and radiology reports was performed to develop and validate ARC algorithms. Reports were manually classified as diagnostic of HCC or not. ARC generated document classification algorithms using the Clinical Text Analysis and Knowledge Extraction System. ARC performance was compared to manual classification. PPV, sensitivity, and specificity of ARC were calculated. Results 1138 patients with HCC were identified by ICD-9 codes. Based on manual review, 773 had HCC. The HCC ICD-9 code algorithm had a PPV of 0.67, sensitivity of 0.95, and specificity of 0.93. For a random subset of 619 patients, we identified 471 pathology reports for 323 patients and 943 radiology reports for 557 patients. The pathology ARC algorithm had PPV of 0.96, sensitivity of 0.96, and specificity of 0.97. The radiology ARC algorithm had PPV of 0.75, sensitivity of 0.94, and specificity of 0.68. Conclusion A combined approach of ICD-9 codes and NLP of pathology and radiology reports improves HCC case identification in automated data. PMID:23929403

Validation of Case Finding Algorithms for Hepatocellular Cancer From Administrative Data and Electronic Health Records Using Natural Language Processing.

PubMed

Sada, Yvonne; Hou, Jason; Richardson, Peter; El-Serag, Hashem; Davila, Jessica

2016-02-01

Accurate identification of hepatocellular cancer (HCC) cases from automated data is needed for efficient and valid quality improvement initiatives and research. We validated HCC International Classification of Diseases, 9th Revision (ICD-9) codes, and evaluated whether natural language processing by the Automated Retrieval Console (ARC) for document classification improves HCC identification. We identified a cohort of patients with ICD-9 codes for HCC during 2005-2010 from Veterans Affairs administrative data. Pathology and radiology reports were reviewed to confirm HCC. The positive predictive value (PPV), sensitivity, and specificity of ICD-9 codes were calculated. A split validation study of pathology and radiology reports was performed to develop and validate ARC algorithms. Reports were manually classified as diagnostic of HCC or not. ARC generated document classification algorithms using the Clinical Text Analysis and Knowledge Extraction System. ARC performance was compared with manual classification. PPV, sensitivity, and specificity of ARC were calculated. A total of 1138 patients with HCC were identified by ICD-9 codes. On the basis of manual review, 773 had HCC. The HCC ICD-9 code algorithm had a PPV of 0.67, sensitivity of 0.95, and specificity of 0.93. For a random subset of 619 patients, we identified 471 pathology reports for 323 patients and 943 radiology reports for 557 patients. The pathology ARC algorithm had PPV of 0.96, sensitivity of 0.96, and specificity of 0.97. The radiology ARC algorithm had PPV of 0.75, sensitivity of 0.94, and specificity of 0.68. A combined approach of ICD-9 codes and natural language processing of pathology and radiology reports improves HCC case identification in automated data.

Early estimates of SEER cancer incidence, 2014.

PubMed

Lewis, Denise Riedel; Chen, Huann-Sheng; Cockburn, Myles G; Wu, Xiao-Cheng; Stroup, Antoinette M; Midthune, Douglas N; Zou, Zhaohui; Krapcho, Martin F; Miller, Daniel G; Feuer, Eric J

2017-07-01

Cancer incidence rates and trends for cases diagnosed through 2014 using data reported to the Surveillance, Epidemiology, and End Results (SEER) program in February 2016 and a validation of rates and trends for cases diagnosed through 2013 and submitted in February 2015 using the November 2015 submission are reported. New cancer sites include the pancreas, kidney and renal pelvis, corpus and uterus, and childhood cancer sites for ages birth to 19 years inclusive. A new reporting delay model is presented for these estimates for more consistent results with the model used for the usual November SEER submissions, adjusting for the large case undercount in the February submission. Joinpoint regression methodology was used to assess trends. Delay-adjusted rates and trends were checked for validity between the February 2016 and November 2016 submissions. Validation revealed that the delay model provides similar estimates of eventual counts using either February or November submission data. Trends declined through 2014 for prostate and colon and rectum cancer for males and females, male and female lung cancer, and cervical cancer. Thyroid cancer and liver and intrahepatic bile duct cancer increased. Pancreas (male and female) and corpus and uterus cancer demonstrated a modest increase. Slight increases occurred for male kidney and renal pelvis, and for all childhood cancer sites for ages birth to 19 years. Evaluating early cancer data submissions, adjusted for reporting delay, produces timely and valid incidence rates and trends. The results of the current study support using delay-adjusted February submission data for valid incidence rate and trend estimates over several data cycles. Cancer 2017;123:2524-34. © 2017 American Cancer Society. © 2017 American Cancer Society. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

Statistical Validation of Image Segmentation Quality Based on a Spatial Overlap Index1

PubMed Central

Zou, Kelly H.; Warfield, Simon K.; Bharatha, Aditya; Tempany, Clare M.C.; Kaus, Michael R.; Haker, Steven J.; Wells, William M.; Jolesz, Ferenc A.; Kikinis, Ron

2005-01-01

Rationale and Objectives To examine a statistical validation method based on the spatial overlap between two sets of segmentations of the same anatomy. Materials and Methods The Dice similarity coefficient (DSC) was used as a statistical validation metric to evaluate the performance of both the reproducibility of manual segmentations and the spatial overlap accuracy of automated probabilistic fractional segmentation of MR images, illustrated on two clinical examples. Example 1: 10 consecutive cases of prostate brachytherapy patients underwent both preoperative 1.5T and intraoperative 0.5T MR imaging. For each case, 5 repeated manual segmentations of the prostate peripheral zone were performed separately on preoperative and on intraoperative images. Example 2: A semi-automated probabilistic fractional segmentation algorithm was applied to MR imaging of 9 cases with 3 types of brain tumors. DSC values were computed and logit-transformed values were compared in the mean with the analysis of variance (ANOVA). Results Example 1: The mean DSCs of 0.883 (range, 0.876–0.893) with 1.5T preoperative MRI and 0.838 (range, 0.819–0.852) with 0.5T intraoperative MRI (P < .001) were within and at the margin of the range of good reproducibility, respectively. Example 2: Wide ranges of DSC were observed in brain tumor segmentations: Meningiomas (0.519–0.893), astrocytomas (0.487–0.972), and other mixed gliomas (0.490–0.899). Conclusion The DSC value is a simple and useful summary measure of spatial overlap, which can be applied to studies of reproducibility and accuracy in image segmentation. We observed generally satisfactory but variable validation results in two clinical applications. This metric may be adapted for similar validation tasks. PMID:14974593

Cross-cultural adaptation and validation of the sino-nasal outcome test (SNOT-22) for Spanish-speaking patients.

PubMed

de los Santos, Gonzalo; Reyes, Pablo; del Castillo, Raúl; Fragola, Claudio; Royuela, Ana

2015-11-01

Our objective was to perform translation, cross-cultural adaptation and validation of the sino-nasal outcome test 22 (SNOT-22) to Spanish language. SNOT-22 was translated, back translated, and a pretest trial was performed. The study included 119 individuals divided into 60 cases, who met diagnostic criteria for chronic rhinosinusitis according to the European Position Paper on Rhinosinusitis 2012; and 59 controls, who reported no sino-nasal disease. Internal consistency was evaluated with Cronbach's alpha test, reproducibility with Kappa coefficient, reliability with intraclass correlation coefficient (ICC), validity with Mann-Whitney U test and responsiveness with Wilcoxon test. In cases, Cronbach's alpha was 0.91 both before and after treatment, as for controls, it was 0.90 at their first test assessment and 0.88 at 3 weeks. Kappa coefficient was calculated for each item, with an average score of 0.69. ICC was also performed for each item, with a score of 0.87 in the overall score and an average among all items of 0.71. Median score for cases was 47, and 2 for controls, finding the difference to be highly significant (Mann-Whitney U test, p < 0.001). Clinical changes were observed among treated patients, with a median score of 47 and 13.5 before and after treatment, respectively (Wilcoxon test, p < 0.001). The effect size resulted in 0.14 in treated patients whose status at 3 weeks was unvarying; 1.03 in those who were better and 1.89 for much better group. All controls were unvarying with an effect size of 0.05. The Spanish version of the SNOT-22 has the internal consistency, reliability, reproducibility, validity and responsiveness necessary to be a valid instrument to be used in clinical practice.

Face and construct validity of a computer-based virtual reality simulator for ERCP.

PubMed

Bittner, James G; Mellinger, John D; Imam, Toufic; Schade, Robert R; Macfadyen, Bruce V

2010-02-01

Currently, little evidence supports computer-based simulation for ERCP training. To determine face and construct validity of a computer-based simulator for ERCP and assess its perceived utility as a training tool. Novice and expert endoscopists completed 2 simulated ERCP cases by using the GI Mentor II. Virtual Education and Surgical Simulation Laboratory, Medical College of Georgia. Outcomes included times to complete the procedure, reach the papilla, and use fluoroscopy; attempts to cannulate the papilla, pancreatic duct, and common bile duct; and number of contrast injections and complications. Subjects assessed simulator graphics, procedural accuracy, difficulty, haptics, overall realism, and training potential. Only when performance data from cases A and B were combined did the GI Mentor II differentiate novices and experts based on times to complete the procedure, reach the papilla, and use fluoroscopy. Across skill levels, overall opinions were similar regarding graphics (moderately realistic), accuracy (similar to clinical ERCP), difficulty (similar to clinical ERCP), overall realism (moderately realistic), and haptics. Most participants (92%) claimed that the simulator has definite training potential or should be required for training. Small sample size, single institution. The GI Mentor II demonstrated construct validity for ERCP based on select metrics. Most subjects thought that the simulated graphics, procedural accuracy, and overall realism exhibit face validity. Subjects deemed it a useful training tool. Study repetition involving more participants and cases may help confirm results and establish the simulator's ability to differentiate skill levels based on ERCP-specific metrics.

Measurement of COPD Severity Using a Survey-Based Score

PubMed Central

Omachi, Theodore A.; Katz, Patricia P.; Yelin, Edward H.; Iribarren, Carlos; Blanc, Paul D.

2010-01-01

Background: A comprehensive survey-based COPD severity score has usefulness for epidemiologic and health outcomes research. We previously developed and validated the survey-based COPD Severity Score without using lung function or other physiologic measurements. In this study, we aimed to further validate the severity score in a different COPD cohort and using a combination of patient-reported and objective physiologic measurements. Methods: Using data from the Function, Living, Outcomes, and Work cohort study of COPD, we evaluated the concurrent and predictive validity of the COPD Severity Score among 1,202 subjects. The survey instrument is a 35-point score based on symptoms, medication and oxygen use, and prior hospitalization or intubation for COPD. Subjects were systemically assessed using structured telephone survey, spirometry, and 6-min walk testing. Results: We found evidence to support concurrent validity of the score. Higher COPD Severity Score values were associated with poorer FEV1 (r = −0.38), FEV1% predicted (r = −0.40), Body mass, Obstruction, Dyspnea, Exercise Index (r = 0.57), and distance walked in 6 min (r = −0.43) (P < .0001 in all cases). Greater COPD severity was also related to poorer generic physical health status (r = −0.49) and disease-specific health-related quality of life (r = 0.57) (P < .0001). The score also demonstrated predictive validity. It was also associated with a greater prospective risk of acute exacerbation of COPD defined as ED visits (hazard ratio [HR], 1.31; 95% CI, 1.24-1.39), hospitalizations (HR, 1.59; 95% CI, 1.44-1.75), and either measure of hospital-based care for COPD (HR, 1.34; 95% CI, 1.26-1.41) (P < .0001 in all cases). Conclusion: The COPD Severity Score is a valid survey-based measure of disease-specific severity, both in terms of concurrent and predictive validity. The score is a psychometrically sound instrument for use in epidemiologic and outcomes research in COPD. PMID:20040611

Ecological periodic tables for benthic macrofaunal usage of estuarine habitats : Insights from a case study in Tillamook bay, Oregon, USA

EPA Science Inventory

This study validates the ecological relevance of estuarine habitat types to the benthic macrofaunal community and, together with previous similar studies, suggests they can serve as elements in ecological periodic tables of benthic macrofaunal usage in the bioregion. We compared...

Students' Perspectives on E-Portfolio Development and Implementation: A Case Study in Taiwanese Higher Education

ERIC Educational Resources Information Center

Hsieh, Pei-Hsuan; Lee, Chun-I; Chen, Wei-Fan

2015-01-01

This study explores students' perceptions related to the implementation of e-portfolios in the context of Taiwanese higher education. Thirty Taiwanese university students were interviewed, and data analysis includes 14 interviewees' e-portfolios and responses to 281 valid surveys from non-interviewed students. The study presents students'…

All-sky photogrammetry techniques to georeference a cloud field

NASA Astrophysics Data System (ADS)

Crispel, Pierre; Roberts, Gregory

2018-01-01

In this study, we present a novel method of identifying and geolocalizing cloud field elements from a portable all-sky camera stereo network based on the ground and oriented towards zenith. The methodology is mainly based on stereophotogrammetry which is a 3-D reconstruction technique based on triangulation from corresponding stereo pixels in rectified images. In cases where clouds are horizontally separated, identifying individual positions is performed with segmentation techniques based on hue filtering and contour detection algorithms. Macroscopic cloud field characteristics such as cloud layer base heights and velocity fields are also deduced. In addition, the methodology is fitted to the context of measurement campaigns which impose simplicity of implementation, auto-calibration, and portability. Camera internal geometry models are achieved a priori in the laboratory and validated to ensure a certain accuracy in the peripheral parts of the all-sky image. Then, stereophotogrammetry with dense 3-D reconstruction is applied with cameras spaced 150 m apart for two validation cases. The first validation case is carried out with cumulus clouds having a cloud base height at 1500 m a.g.l. The second validation case is carried out with two cloud layers: a cumulus fractus layer with a base height at 1000 m a.g.l. and an altocumulus stratiformis layer with a base height of 2300 m a.g.l. Velocity fields at cloud base are computed by tracking image rectangular patterns through successive shots. The height uncertainty is estimated by comparison with a Vaisala CL31 ceilometer located on the site. The uncertainty on the horizontal coordinates and on the velocity field are theoretically quantified by using the experimental uncertainties of the cloud base height and camera orientation. In the first cumulus case, segmentation of the image is performed to identify individuals clouds in the cloud field and determine the horizontal positions of the cloud centers.

Beyond Corroboration: Strengthening Model Validation by Looking for Unexpected Patterns

PubMed Central

Chérel, Guillaume; Cottineau, Clémentine; Reuillon, Romain

2015-01-01

Models of emergent phenomena are designed to provide an explanation to global-scale phenomena from local-scale processes. Model validation is commonly done by verifying that the model is able to reproduce the patterns to be explained. We argue that robust validation must not only be based on corroboration, but also on attempting to falsify the model, i.e. making sure that the model behaves soundly for any reasonable input and parameter values. We propose an open-ended evolutionary method based on Novelty Search to look for the diverse patterns a model can produce. The Pattern Space Exploration method was tested on a model of collective motion and compared to three common a priori sampling experiment designs. The method successfully discovered all known qualitatively different kinds of collective motion, and performed much better than the a priori sampling methods. The method was then applied to a case study of city system dynamics to explore the model’s predicted values of city hierarchisation and population growth. This case study showed that the method can provide insights on potential predictive scenarios as well as falsifiers of the model when the simulated dynamics are highly unrealistic. PMID:26368917

Predicting child maltreatment: A meta-analysis of the predictive validity of risk assessment instruments.

PubMed

van der Put, Claudia E; Assink, Mark; Boekhout van Solinge, Noëlle F

2017-11-01

Risk assessment is crucial in preventing child maltreatment since it can identify high-risk cases in need of child protection intervention. Despite widespread use of risk assessment instruments in child welfare, it is unknown how well these instruments predict maltreatment and what instrument characteristics are associated with higher levels of predictive validity. Therefore, a multilevel meta-analysis was conducted to examine the predictive accuracy of (characteristics of) risk assessment instruments. A literature search yielded 30 independent studies (N=87,329) examining the predictive validity of 27 different risk assessment instruments. From these studies, 67 effect sizes could be extracted. Overall, a medium significant effect was found (AUC=0.681), indicating a moderate predictive accuracy. Moderator analyses revealed that onset of maltreatment can be better predicted than recurrence of maltreatment, which is a promising finding for early detection and prevention of child maltreatment. In addition, actuarial instruments were found to outperform clinical instruments. To bring risk and needs assessment in child welfare to a higher level, actuarial instruments should be further developed and strengthened by distinguishing risk assessment from needs assessment and by integrating risk assessment with case management. Copyright © 2017 Elsevier Ltd. All rights reserved.

Combating Terrorism: A Case Study of Nigeria Against Boko Haram Terrorist Group

DTIC Science & Technology

2014-06-13

RESPONSIBLE PERSON a. REPORT b. ABSTRACT c. THIS PAGE 19b. PHONE NUMBER (include area code) (U) (U) (U) (U) 135 Standard Form 298 (Rev. 8-98...penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number . PLEASE DO NOT RETURN...2014 4. TITLE AND SUBTITLE Combating Terrorism: A Case Study of Nigeria Against Boko Haram Terrorist Group 5a. CONTRACT NUMBER 5b. GRANT

Comments on: blood product transfusion in emergency department patients: a case control study of practice patterns and impact on outcome.

PubMed

Karami, Manoochehr; Khazaei, Salman

2017-12-06

Clinical decision makings according studies result require the valid and correct data collection, andanalysis. However, there are some common methodological and statistical issues which may ignore by authors. In individual matched case- control design bias arising from the unconditional analysis instead of conditional analysis. Using an unconditional logistic for matched data causes the imposition of a large number of nuisance parameters which may result in seriously biased estimates.

A Human Proximity Operations System test case validation approach

NASA Astrophysics Data System (ADS)

Huber, Justin; Straub, Jeremy

A Human Proximity Operations System (HPOS) poses numerous risks in a real world environment. These risks range from mundane tasks such as avoiding walls and fixed obstacles to the critical need to keep people and processes safe in the context of the HPOS's situation-specific decision making. Validating the performance of an HPOS, which must operate in a real-world environment, is an ill posed problem due to the complexity that is introduced by erratic (non-computer) actors. In order to prove the HPOS's usefulness, test cases must be generated to simulate possible actions of these actors, so the HPOS can be shown to be able perform safely in environments where it will be operated. The HPOS must demonstrate its ability to be as safe as a human, across a wide range of foreseeable circumstances. This paper evaluates the use of test cases to validate HPOS performance and utility. It considers an HPOS's safe performance in the context of a common human activity, moving through a crowded corridor, and extrapolates (based on this) to the suitability of using test cases for AI validation in other areas of prospective application.

Meta-analysis of screening and case finding tools for depression in cancer: evidence based recommendations for clinical practice on behalf of the Depression in Cancer Care consensus group.

PubMed

Mitchell, Alex J; Meader, Nick; Davies, Evan; Clover, Kerrie; Carter, Gregory L; Loscalzo, Matthew J; Linden, Wolfgang; Grassi, Luigi; Johansen, Christoffer; Carlson, Linda E; Zabora, James

2012-10-01

To examine the validity of screening and case-finding tools used in the identification of depression as defined by an ICD10/DSM-IV criterion standard. We identified 63 studies involving 19 tools (in 33 publications) designed to help clinicians identify depression in cancer settings. We used a standardized rating system. We excluded 11 tools without at least two independent studies, leaving 8 tools for comparison. Across all cancer stages there were 56 diagnostic validity studies (n=10,009). For case-finding, one stem question, two stem questions and the BDI-II all had level 2 evidence (2a, 2b and 2c respectively) and given their better acceptability we gave the stem questions a grade B recommendation. For screening, two stem questions had level 1b evidence (with high acceptability) and the BDI-II had level 2c evidence. For every 100 people screened in advanced cancer, the two questions would accurately detect 18 cases, while missing only 1 and correctly reassure 74 with 7 falsely identified. For every 100 people screened in non-palliative settings the BDI-II would accurately detect 17 cases, missing 2 and correctly re-assure 70, with 11 falsely identified as cases. The main cautions are the reliance on DSM-IV definitions of major depression, the large number of small studies and the paucity of data for many tools in specific settings. Although no single tool could be offered unqualified support, several tools are likely to improve upon unassisted clinical recognition. In clinical practice, all tools should form part of an integrated approach involving further follow-up, clinical assessment and evidence based therapy. Copyright © 2012 Elsevier B.V. All rights reserved.

Validation of ICD-9 Codes for Stable Miscarriage in the Emergency Department.

PubMed

Quinley, Kelly E; Falck, Ailsa; Kallan, Michael J; Datner, Elizabeth M; Carr, Brendan G; Schreiber, Courtney A

2015-07-01

International Classification of Disease, Ninth Revision (ICD-9) diagnosis codes have not been validated for identifying cases of missed abortion where a pregnancy is no longer viable but the cervical os remains closed. Our goal was to assess whether ICD-9 code "632" for missed abortion has high sensitivity and positive predictive value (PPV) in identifying patients in the emergency department (ED) with cases of stable early pregnancy failure (EPF). We studied females ages 13-50 years presenting to the ED of an urban academic medical center. We approached our analysis from two perspectives, evaluating both the sensitivity and PPV of ICD-9 code "632" in identifying patients with stable EPF. All patients with chief complaints "pregnant and bleeding" or "pregnant and cramping" over a 12-month period were identified. We randomly reviewed two months of patient visits and calculated the sensitivity of ICD-9 code "632" for true cases of stable miscarriage. To establish the PPV of ICD-9 code "632" for capturing missed abortions, we identified patients whose visits from the same time period were assigned ICD-9 code "632," and identified those with actual cases of stable EPF. We reviewed 310 patient records (17.6% of 1,762 sampled). Thirteen of 31 patient records assigned ICD-9 code for missed abortion correctly identified cases of stable EPF (sensitivity=41.9%), and 140 of the 142 patients without EPF were not assigned the ICD-9 code "632"(specificity=98.6%). Of the 52 eligible patients identified by ICD-9 code "632," 39 cases met the criteria for stable EPF (PPV=75.0%). ICD-9 code "632" has low sensitivity for identifying stable EPF, but its high specificity and moderately high PPV are valuable for studying cases of stable EPF in epidemiologic studies using administrative data.

Multimodal Navigation in Endoscopic Transsphenoidal Resection of Pituitary Tumors using Image-based Vascular and Cranial Nerve Segmentation: A Prospective Validation Study

PubMed Central

Dolati, Parviz; Eichberg, Daniel; Golby, Alexandra; Zamani, Amir; Laws, Edward

2016-01-01

Introduction Transsphenoidal surgery (TSS) is a well-known approach for the treatment of pituitary tumors. However, lateral misdirection and vascular damage, intraoperative CSF leakage, and optic nerve and vascular injuries are all well-known complications, and the risk of adverse events is more likely in less experienced hands. This prospective study was conducted to validate the accuracy of image-based segmentation in localization of neurovascular structures during TSS. Methods Twenty-five patients with pituitary tumors underwent preoperative 3TMRI, which included thin-sectioned 3D space T2, 3D Time of Flight and MPRAGE sequences. Images were reviewed by an expert independent neuroradiologist. Imaging sequences were loaded in BrainLab iPlanNet (16/25 cases) or Stryker (9/25 cases) image guidance platforms for segmentation and pre-operative planning. After patient registration into the neuronavigation system and subsequent surgical exposure, each segmented neural or vascular element was validated by manual placement of the navigation probe on or as close as possible to the target. The audible pulsations of the bilateral ICA were confirmed using a micro-Doppler probe. Results Pre-operative segmentation of the ICA and cavernous sinus matched with the intra-operative endoscopic and micro-Doppler findings in all cases (Dice Similarity Coefficient =1). This information reassured the surgeons with regard to the lateral extent of bone removal at the sellar floor and the limits of lateral exploration. Excellent correspondence between image-based segmentation and the endoscopic view was also evident at the surface of the tumor and at the tumor-normal gland interfaces. This assisted in preventing unnecessary removal of the normal pituitary gland. Image-guidance assisted the surgeons in localizing the optic nerve and chiasm in 64% of the cases and the diaphragma sella in 52% of cases, which helped to determine the limits of upward exploration and to decrease the risk of CSF leakage. The accuracy of the measurements was 1.20 + 0.21 mm (mean +/−SD). Conclusion Image-based pre-operative vascular and neural element segmentation, especially with 3D reconstruction, is highly informative preoperatively and potentially could assist less experienced neurosurgeons in preventing vascular and neural injury during TSS. Additionally, the accuracy found in this study is comparable to previously reported neuronavigation measurements. This novel preliminary study is encouraging for future prospective intraoperative validation with larger numbers of patients. PMID:27302558

Evaluation of the confusion matrix method in the validation of an automated system for measuring feeding behaviour of cattle.

PubMed

Ruuska, Salla; Hämäläinen, Wilhelmiina; Kajava, Sari; Mughal, Mikaela; Matilainen, Pekka; Mononen, Jaakko

2018-03-01

The aim of the present study was to evaluate empirically confusion matrices in device validation. We compared the confusion matrix method to linear regression and error indices in the validation of a device measuring feeding behaviour of dairy cattle. In addition, we studied how to extract additional information on classification errors with confusion probabilities. The data consisted of 12 h behaviour measurements from five dairy cows; feeding and other behaviour were detected simultaneously with a device and from video recordings. The resulting 216 000 pairs of classifications were used to construct confusion matrices and calculate performance measures. In addition, hourly durations of each behaviour were calculated and the accuracy of measurements was evaluated with linear regression and error indices. All three validation methods agreed when the behaviour was detected very accurately or inaccurately. Otherwise, in the intermediate cases, the confusion matrix method and error indices produced relatively concordant results, but the linear regression method often disagreed with them. Our study supports the use of confusion matrix analysis in validation since it is robust to any data distribution and type of relationship, it makes a stringent evaluation of validity, and it offers extra information on the type and sources of errors. Copyright © 2018 Elsevier B.V. All rights reserved.

Hospitalized stroke surveillance in the community of Durango, Mexico: the brain attack surveillance in Durango study.

PubMed

Cantu-Brito, Carlos; Majersik, Jennifer J; Sánchez, Brisa N; Ruano, Angel; Quiñones, Gerardo; Arzola, José; Morgenstern, Lewis B

2010-05-01

Vascular conditions are becoming the greatest cause of morbidity and mortality in developing countries. Few studies exist in Latin America. We aimed to perform a rigorous stroke surveillance study in Durango, Mexico. Active and passive surveillance were used to identify all patients with potential stroke presenting to Durango Municipality hospitals from August 2007 to July 2008. Exclusion criteria were subjects younger than 25 years old, stroke attributable to head trauma, and non-Durango Municipality residents. Brain Attack Surveillance in Durango-trained neurologists validated cases as stroke using source documentation. Stroke hospitalization rates were defined to include patients examined in the emergency department or admitted to the hospital. Abstractors identified 435 potential cases; 309 (71%) were validated as stroke. Of the validated stroke cases, the median age was 71 and 49% were female. Subtypes were 61.5% ischemic stroke, 20.7% intracerebral hemorrhage, 7.4% subarachnoid hemorrhage, and 10.4% undetermined. Overall initial NIHSS was a median of 11 (interquartile range, 7-17); in-hospital mortality was 39%. When adjusted to the world population, the age-adjusted hospitalization rate of first-ever stroke was 118.2 per 100 000; rates by type were: ischemic stroke, 69.1 (95% CI, 57.5-80.7); intracerebral hemorrhage, 26.7 (95% CI, 19.6-33.8); subarachnoid hemorrhage, 9.5 (95% CI, 5.3-13.8); and unknown, 12.3 (95% CI, 7.4-17.3). Of 190 patients with validated ischemic stroke, 44.2% received lipid testing and 7.4% received carotid imaging and echocardiography; 1.1% received tissue plasminogen activator. To our knowledge, this is the first estimate of stroke hospitalization rates in a Mexican community and it provides information important for design of interventions to prevent and treat stroke. This information is critical to reduce Mexico's stroke burden.

Ethical leadership: meta-analytic evidence of criterion-related and incremental validity.

PubMed

Ng, Thomas W H; Feldman, Daniel C

2015-05-01

This study examines the criterion-related and incremental validity of ethical leadership (EL) with meta-analytic data. Across 101 samples published over the last 15 years (N = 29,620), we observed that EL demonstrated acceptable criterion-related validity with variables that tap followers' job attitudes, job performance, and evaluations of their leaders. Further, followers' trust in the leader mediated the relationships of EL with job attitudes and performance. In terms of incremental validity, we found that EL significantly, albeit weakly in some cases, predicted task performance, citizenship behavior, and counterproductive work behavior-even after controlling for the effects of such variables as transformational leadership, use of contingent rewards, management by exception, interactional fairness, and destructive leadership. The article concludes with a discussion of ways to strengthen the incremental validity of EL. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Effectiveness of brief VR treatment for PTSD in war-fighters: a case study.

PubMed

Miyahira, Sarah D; Folen, Raymond A; Hoffman, Hunter G; Garcia-Palacios, Azucena; Schaper, Kim M

2010-01-01

War-fighters exposed to combat are at high risk for developing posttraumatic stress disorder (PTSD), a complex and challenging condition to treat. Cognitive behavioral therapies (CBT) have been empirically validated as effective treatments for PTSD resulting from sexual assault, vehicular accidents, and disasters. Exposure, imaginal or in vivo, to the traumatic event is a central component of successful CBT treatment. Early studies indicate that CBT with brief virtual reality exposure (VRE) is beneficial in treating PTSD. The case study examined the effectiveness of brief VRE in treating combat-related PTSD.

Evaluating the validity of clinical codes to identify cataract and glaucoma in the UK Clinical Practice Research Datalink.

PubMed

Kang, Elizabeth M; Pinheiro, Simone P; Hammad, Tarek A; Abou-Ali, Adel

2015-01-01

The aim of this study is to determine (i) the positive predictive value (PPV) of an algorithm using clinical codes to identify incident glaucoma and cataract events in the Clinical Practice Research Datalink (CPRD) and (ii) the ability to capture the correct timing of these clinical events. A total of 21,339 and 5349 potential cataract and glaucoma cases, respectively, were identified in CPRD between 1 January 1990 and 31 December 2010. Questionnaires were sent to the general practitioners (GP) of 1169 (5.5%) cataract and 1163 (21.7%) glaucoma cases for validation. GPs were asked to verify the diagnosis and the timing of the diagnosis and to provide other supporting information. A total of 986 (84.3%) valid cataract questionnaires and 863 (74.2%) glaucoma questionnaires were completed. 92.1% and 92.4% of these used information beyond EMR to verify the diagnosis. Cataract and glaucoma diagnoses were confirmed in the large majority of the cases. The PPV (95% CI) of the cataract and glaucoma Read code algorithm were 92.0% (90.3-93.7%) and 84.1% (81.7-86.6%), respectively. However, timing of diagnosis was incorrect for a substantial proportion of the cases (20.3% and 32.8% of the cataract and glaucoma cases, respectively) among whom 30.4% and 49.2% had discrepancies in diagnosis timing greater than 1 year. High PPV suggests that the algorithms based on the clinical Read codes are sufficient to identify the cataract and glaucoma cases in CPRD. However, these codes alone may not be able to accurately identify the timing of the diagnosis of these eye disorders. Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

Validation of a GPU-based Monte Carlo code (gPMC) for proton radiation therapy: clinical cases study.

PubMed

Giantsoudi, Drosoula; Schuemann, Jan; Jia, Xun; Dowdell, Stephen; Jiang, Steve; Paganetti, Harald

2015-03-21

Monte Carlo (MC) methods are recognized as the gold-standard for dose calculation, however they have not replaced analytical methods up to now due to their lengthy calculation times. GPU-based applications allow MC dose calculations to be performed on time scales comparable to conventional analytical algorithms. This study focuses on validating our GPU-based MC code for proton dose calculation (gPMC) using an experimentally validated multi-purpose MC code (TOPAS) and compare their performance for clinical patient cases. Clinical cases from five treatment sites were selected covering the full range from very homogeneous patient geometries (liver) to patients with high geometrical complexity (air cavities and density heterogeneities in head-and-neck and lung patients) and from short beam range (breast) to large beam range (prostate). Both gPMC and TOPAS were used to calculate 3D dose distributions for all patients. Comparisons were performed based on target coverage indices (mean dose, V95, D98, D50, D02) and gamma index distributions. Dosimetric indices differed less than 2% between TOPAS and gPMC dose distributions for most cases. Gamma index analysis with 1%/1 mm criterion resulted in a passing rate of more than 94% of all patient voxels receiving more than 10% of the mean target dose, for all patients except for prostate cases. Although clinically insignificant, gPMC resulted in systematic underestimation of target dose for prostate cases by 1-2% compared to TOPAS. Correspondingly the gamma index analysis with 1%/1 mm criterion failed for most beams for this site, while for 2%/1 mm criterion passing rates of more than 94.6% of all patient voxels were observed. For the same initial number of simulated particles, calculation time for a single beam for a typical head and neck patient plan decreased from 4 CPU hours per million particles (2.8-2.9 GHz Intel X5600) for TOPAS to 2.4 s per million particles (NVIDIA TESLA C2075) for gPMC. Excellent agreement was demonstrated between our fast GPU-based MC code (gPMC) and a previously extensively validated multi-purpose MC code (TOPAS) for a comprehensive set of clinical patient cases. This shows that MC dose calculations in proton therapy can be performed on time scales comparable to analytical algorithms with accuracy comparable to state-of-the-art CPU-based MC codes.

Measuring Primary Students' Graph Interpretation Skills Via a Performance Assessment: A case study in instrument development

NASA Astrophysics Data System (ADS)

Peterman, Karen; Cranston, Kayla A.; Pryor, Marie; Kermish-Allen, Ruth

2015-11-01

This case study was conducted within the context of a place-based education project that was implemented with primary school students in the USA. The authors and participating teachers created a performance assessment of standards-aligned tasks to examine 6-10-year-old students' graph interpretation skills as part of an exploratory research project. Fifty-five students participated in a performance assessment interview at the beginning and end of a place-based investigation. Two forms of the assessment were created and counterbalanced within class at pre and post. In situ scoring was conducted such that responses were scored as correct versus incorrect during the assessment's administration. Criterion validity analysis demonstrated an age-level progression in student scores. Tests of discriminant validity showed that the instrument detected variability in interpretation skills across each of three graph types (line, bar, dot plot). Convergent validity was established by correlating in situ scores with those from the Graph Interpretation Scoring Rubric. Students' proficiency with interpreting different types of graphs matched expectations based on age and the standards-based progression of graphs across primary school grades. The assessment tasks were also effective at detecting pre-post gains in students' interpretation of line graphs and dot plots after the place-based project. The results of the case study are discussed in relation to the common challenges associated with performance assessment. Implications are presented in relation to the need for authentic and performance-based instructional and assessment tasks to respond to the Common Core State Standards and the Next Generation Science Standards.

Consistency, Verification, and Validation of Turbulence Models for Reynolds-Averaged Navier-Stokes Applications

NASA Technical Reports Server (NTRS)

Rumsey, Christopher L.

2009-01-01

In current practice, it is often difficult to draw firm conclusions about turbulence model accuracy when performing multi-code CFD studies ostensibly using the same model because of inconsistencies in model formulation or implementation in different codes. This paper describes an effort to improve the consistency, verification, and validation of turbulence models within the aerospace community through a website database of verification and validation cases. Some of the variants of two widely-used turbulence models are described, and two independent computer codes (one structured and one unstructured) are used in conjunction with two specific versions of these models to demonstrate consistency with grid refinement for several representative problems. Naming conventions, implementation consistency, and thorough grid resolution studies are key factors necessary for success.

Results and current status of the NPARC alliance validation effort

NASA Technical Reports Server (NTRS)

Towne, Charles E.; Jones, Ralph R.

1996-01-01

The NPARC Alliance is a partnership between the NASA Lewis Research Center (LeRC) and the USAF Arnold Engineering Development Center (AEDC) dedicated to the establishment of a national CFD capability, centered on the NPARC Navier-Stokes computer program. The three main tasks of the Alliance are user support, code development, and validation. The present paper is a status report on the validation effort. It describes the validation approach being taken by the Alliance. Representative results are presented for laminar and turbulent flat plate boundary layers, a supersonic axisymmetric jet, and a glancing shock/turbulent boundary layer interaction. Cases scheduled to be run in the future are also listed. The archive of validation cases is described, including information on how to access it via the Internet.

Making transit-oriented development work in low-income Latino neighborhoods : a comparative case study of Boyle Heights, Los Angeles and Logan Heights, San Diego.

DOT National Transportation Integrated Search

2016-12-01

This research project is a continuation of a previous NITC-funded study. The first study compared the MacArthur Park TOD in Los Angeles to the : Fruitvale Village TOD in Oakland. The findings from this new study further validate the key findings from...

A Study of Sustainable Assessment Theory in Higher Education Tutorials

ERIC Educational Resources Information Center

Beck, Robert J.; Skinner, William F.; Schwabrow, Lynsey A.

2013-01-01

A study of sustainable assessment theory in nine tutorial courses at four colleges demonstrated that three long-term learning outcomes improved: Independence, Intellectual Maturity and Creativity. Eight of 10 traits associated with these outcomes were validated through internal reliability, faculty and student rubrics, and faculty case studies…

Validation of intensive care unit-acquired infection surveillance in the Italian SPIN-UTI network.

PubMed

Masia, M D; Barchitta, M; Liperi, G; Cantù, A P; Alliata, E; Auxilia, F; Torregrossa, V; Mura, I; Agodi, A

2010-10-01

Validity is one of the most critical factors concerning surveillance of nosocomial infections (NIs). This article describes the first validation study of the Italian Nosocomial Infections Surveillance in Intensive Care Units (ICUs) project (SPIN-UTI) surveillance data. The objective was to validate infection data and thus to determine the sensitivity, specificity, and positive and negative predictive values of NI data reported on patients in the ICUs participating in the SPIN-UTI network. A validation study was performed at the end of the surveillance period. All medical records including all clinical and laboratory data were reviewed retrospectively by the trained physicians of the validation team and a positive predictive value (PPV), a negative predictive value (NPV), sensitivity and specificity were calculated. Eight ICUs (16.3%) were randomly chosen from all 49 SPIN-UTI ICUs for the validation study. In total, the validation team reviewed 832 patient charts (27.3% of the SPIN-UTI patients). The PPV was 83.5% and the NPV was 97.3%. The overall sensitivity was 82.3% and overall specificity was 97.2%. Over- and under-reporting of NIs were related to misinterpretation of the case definitions and deviations from the protocol despite previous training and instructions. The results of this study are useful to identify methodological problems within a surveillance system and have been used to plan retraining for surveillance personnel and to design and implement the second phase of the SPIN-UTI project. Copyright 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

Formal Methods for Verification and Validation of Partial Specifications: A Case Study

NASA Technical Reports Server (NTRS)

Easterbrook, Steve; Callahan, John

1997-01-01

This paper describes our work exploring the suitability of formal specification methods for independent verification and validation (IV&V) of software specifications for large, safety critical systems. An IV&V contractor often has to perform rapid analysis on incomplete specifications, with no control over how those specifications are represented. Lightweight formal methods show significant promise in this context, as they offer a way of uncovering major errors, without the burden of full proofs of correctness. We describe a case study of the use of partial formal models for V&V of the requirements for Fault Detection Isolation and Recovery on the space station. We conclude that the insights gained from formalizing a specification are valuable, and it is the process of formalization, rather than the end product that is important. It was only necessary to build enough of the formal model to test the properties in which we were interested. Maintenance of fidelity between multiple representations of the same requirements (as they evolve) is still a problem, and deserves further study.

Sensitivity of self-reported opioid use in case-control studies: Healthy individuals versus hospitalized patients.

PubMed

Rashidian, Hamideh; Hadji, Maryam; Marzban, Maryam; Gholipour, Mahin; Rahimi-Movaghar, Afarin; Kamangar, Farin; Malekzadeh, Reza; Weiderpass, Elisabete; Rezaianzadeh, Abbas; Moradi, Abdolvahab; Babhadi-Ashar, Nima; Ghiasvand, Reza; Khavari-Daneshvar, Hossein; Haghdoost, Ali Akbar; Zendehdel, Kazem

2017-01-01

Several case-control studies have shown associations between the risk of different cancers and self-reported opium use. Inquiring into relatively sensitive issues, such as the history of drug use, is usually prone to information bias. However, in order to justify the findings of these types of studies, we have to quantify the level of such a negative bias. In current study, we aimed to evaluate sensitivity of self-reported opioid use and suggest suitable types of control groups for case-control studies on opioid use and the risk of cancer. In order to compare the validity of the self-reported opioid use, we cross-validated the response of two groups of subjects 1) 178 hospitalized patients and 2) 186 healthy individuals with the results of their tests using urine rapid drug screen (URDS) and thin layer chromatography (TLC). The questioners were asked by trained interviewers to maximize the validity of responses; healthy individuals were selected from the companions of patients in hospitals. Self-reported regular opioid use was 36.5% in hospitalized patients 19.3% in healthy individuals (p-value> 0.001).The reported frequencies of opioid use in the past 72 hours were 21.4% and 11.8% in hospitalized patients and healthy individuals respectively. Comparing their responses with the results of urine tests showed a sensitivity of 77% and 69% among hospitalized patients and healthy individuals for self-reports (p-value = 0.4). Having corrected based on the mentioned sensitivities; the frequency of opioid regular use was 47% and 28% in hospitalized patients and healthy individuals, respectively. Regular opioid use among hospitalized patients was significantly higher than in healthy individuals (p-value> 0.001). Our findings showed that the level of opioid use under-reporting in hospitalized patients and healthy individuals was considerable but comparable. In addition, the frequency of regular opioid use among hospitalized patients was significantly higher than that in the general population. Altogether, it seems that, without corrections for these differences and biases, the results of many studies including case-control studies on opioid use might distort findings substantially.

Sensitivity of self-reported opioid use in case-control studies: Healthy individuals versus hospitalized patients

PubMed Central

Rashidian, Hamideh; Hadji, Maryam; Marzban, Maryam; Gholipour, Mahin; Rahimi-Movaghar, Afarin; Kamangar, Farin; Malekzadeh, Reza; Weiderpass, Elisabete; Rezaianzadeh, Abbas; Moradi, Abdolvahab; Babhadi-Ashar, Nima; Ghiasvand, Reza; Khavari-Daneshvar, Hossein; Haghdoost, Ali Akbar; Zendehdel, Kazem

2017-01-01

Background Several case-control studies have shown associations between the risk of different cancers and self-reported opium use. Inquiring into relatively sensitive issues, such as the history of drug use, is usually prone to information bias. However, in order to justify the findings of these types of studies, we have to quantify the level of such a negative bias. In current study, we aimed to evaluate sensitivity of self-reported opioid use and suggest suitable types of control groups for case-control studies on opioid use and the risk of cancer. Methods In order to compare the validity of the self-reported opioid use, we cross-validated the response of two groups of subjects 1) 178 hospitalized patients and 2) 186 healthy individuals with the results of their tests using urine rapid drug screen (URDS) and thin layer chromatography (TLC). The questioners were asked by trained interviewers to maximize the validity of responses; healthy individuals were selected from the companions of patients in hospitals. Results Self-reported regular opioid use was 36.5% in hospitalized patients 19.3% in healthy individuals (p-value> 0.001).The reported frequencies of opioid use in the past 72 hours were 21.4% and 11.8% in hospitalized patients and healthy individuals respectively. Comparing their responses with the results of urine tests showed a sensitivity of 77% and 69% among hospitalized patients and healthy individuals for self-reports (p-value = 0.4). Having corrected based on the mentioned sensitivities; the frequency of opioid regular use was 47% and 28% in hospitalized patients and healthy individuals, respectively. Regular opioid use among hospitalized patients was significantly higher than in healthy individuals (p-value> 0.001). Conclusion Our findings showed that the level of opioid use under-reporting in hospitalized patients and healthy individuals was considerable but comparable. In addition, the frequency of regular opioid use among hospitalized patients was significantly higher than that in the general population. Altogether, it seems that, without corrections for these differences and biases, the results of many studies including case-control studies on opioid use might distort findings substantially. PMID:28854228

Sherlock Holmes and child psychopathology assessment approaches: the case of the false-positive.

PubMed

Jensen, P S; Watanabe, H

1999-02-01

To explore the relative value of various methods of assessing childhood psychopathology, the authors compared 4 groups of children: those who met criteria for one or more DSM diagnoses and scored high on parent symptom checklists, those who met psychopathology criteria on either one of these two assessment approaches alone, and those who met no psychopathology assessment criterion. Parents of 201 children completed the Child Behavior Checklist (CBCL), after which children and parents were administered the Diagnostic Interview Schedule for Children (version 2.1). Children and parents also completed other survey measures and symptom report inventories. The 4 groups of children were compared against "external validators" to examine the merits of "false-positive" and "false-negative" cases. True-positive cases (those that met DSM criteria and scored high on the CBCL) differed significantly from the true-negative cases on most external validators. "False-positive" and "false-negative" cases had intermediate levels of most risk factors and external validators. "False-positive" cases were not normal per se because they scored significantly above the true-negative group on a number of risk factors and external validators. A similar but less marked pattern was noted for "false-negatives." Findings call into question whether cases with high symptom checklist scores despite no formal diagnoses should be considered "false-positive." Pending the availability of robust markers for mental illness, researchers and clinicians must resist the tendency to reify diagnostic categories or to engage in arcane debates about the superiority of one assessment approach over another.

Integrated Land - Use , Transportation and Environmental Modeling : Validation Case Studies

DOT National Transportation Integrated Search

2010-08-01

For decades the transportation-planning research community has acknowledged the interactions between the evolution of our transportation systems and our land-use, and the need to unify the practices of land-use forecasting and travel-demand modeling ...

Automatic detection of hemorrhagic pericardial effusion on PMCT using deep learning - a feasibility study.

PubMed

Ebert, Lars C; Heimer, Jakob; Schweitzer, Wolf; Sieberth, Till; Leipner, Anja; Thali, Michael; Ampanozi, Garyfalia

2017-12-01

Post mortem computed tomography (PMCT) can be used as a triage tool to better identify cases with a possibly non-natural cause of death, especially when high caseloads make it impossible to perform autopsies on all cases. Substantial data can be generated by modern medical scanners, especially in a forensic setting where the entire body is documented at high resolution. A solution for the resulting issues could be the use of deep learning techniques for automatic analysis of radiological images. In this article, we wanted to test the feasibility of such methods for forensic imaging by hypothesizing that deep learning methods can detect and segment a hemopericardium in PMCT. For deep learning image analysis software, we used the ViDi Suite 2.0. We retrospectively selected 28 cases with, and 24 cases without, hemopericardium. Based on these data, we trained two separate deep learning networks. The first one classified images into hemopericardium/not hemopericardium, and the second one segmented the blood content. We randomly selected 50% of the data for training and 50% for validation. This process was repeated 20 times. The best performing classification network classified all cases of hemopericardium from the validation images correctly with only a few false positives. The best performing segmentation network would tend to underestimate the amount of blood in the pericardium, which is the case for most networks. This is the first study that shows that deep learning has potential for automated image analysis of radiological images in forensic medicine.

A trace map comparison algorithm for the discrete fracture network models of rock masses

NASA Astrophysics Data System (ADS)

Han, Shuai; Wang, Gang; Li, Mingchao

2018-06-01

Discrete fracture networks (DFN) are widely used to build refined geological models. However, validating whether a refined model can match to reality is a crucial problem, concerning whether the model can be used for analysis. The current validation methods include numerical validation and graphical validation. However, the graphical validation, aiming at estimating the similarity between a simulated trace map and the real trace map by visual observation, is subjective. In this paper, an algorithm for the graphical validation of DFN is set up. Four main indicators, including total gray, gray grade curve, characteristic direction and gray density distribution curve, are presented to assess the similarity between two trace maps. A modified Radon transform and loop cosine similarity are presented based on Radon transform and cosine similarity respectively. Besides, how to use Bézier curve to reduce the edge effect is described. Finally, a case study shows that the new algorithm can effectively distinguish which simulated trace map is more similar to the real trace map.

Grid workflow validation using ontology-based tacit knowledge: A case study for quantitative remote sensing applications

NASA Astrophysics Data System (ADS)

Liu, Jia; Liu, Longli; Xue, Yong; Dong, Jing; Hu, Yingcui; Hill, Richard; Guang, Jie; Li, Chi

2017-01-01

Workflow for remote sensing quantitative retrieval is the ;bridge; between Grid services and Grid-enabled application of remote sensing quantitative retrieval. Workflow averts low-level implementation details of the Grid and hence enables users to focus on higher levels of application. The workflow for remote sensing quantitative retrieval plays an important role in remote sensing Grid and Cloud computing services, which can support the modelling, construction and implementation of large-scale complicated applications of remote sensing science. The validation of workflow is important in order to support the large-scale sophisticated scientific computation processes with enhanced performance and to minimize potential waste of time and resources. To research the semantic correctness of user-defined workflows, in this paper, we propose a workflow validation method based on tacit knowledge research in the remote sensing domain. We first discuss the remote sensing model and metadata. Through detailed analysis, we then discuss the method of extracting the domain tacit knowledge and expressing the knowledge with ontology. Additionally, we construct the domain ontology with Protégé. Through our experimental study, we verify the validity of this method in two ways, namely data source consistency error validation and parameters matching error validation.

The influence of validity criteria on Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) test-retest reliability among high school athletes.

PubMed

Brett, Benjamin L; Solomon, Gary S

2017-04-01

Research findings to date on the stability of Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) Composite scores have been inconsistent, requiring further investigation. The use of test validity criteria across these studies also has been inconsistent. Using multiple measures of stability, we examined test-retest reliability of repeated ImPACT baseline assessments in high school athletes across various validity criteria reported in previous studies. A total of 1146 high school athletes completed baseline cognitive testing using the online ImPACT test battery at two time periods of approximately two-year intervals. No participant sustained a concussion between assessments. Five forms of validity criteria used in previous test-retest studies were applied to the data, and differences in reliability were compared. Intraclass correlation coefficients (ICCs) ranged in composite scores from .47 (95% confidence interval, CI [.38, .54]) to .83 (95% CI [.81, .85]) and showed little change across a two-year interval for all five sets of validity criteria. Regression based methods (RBMs) examining the test-retest stability demonstrated a lack of significant change in composite scores across the two-year interval for all forms of validity criteria, with no cases falling outside the expected range of 90% confidence intervals. The application of more stringent validity criteria does not alter test-retest reliability, nor does it account for some of the variation observed across previously performed studies. As such, use of the ImPACT manual validity criteria should be utilized in the determination of test validity and in the individualized approach to concussion management. Potential future efforts to improve test-retest reliability are discussed.

Outcomes of Moral Case Deliberation - the development of an evaluation instrument for clinical ethics support (the Euro-MCD)

PubMed Central

2014-01-01

Background Clinical ethics support, in particular Moral Case Deliberation, aims to support health care providers to manage ethically difficult situations. However, there is a lack of evaluation instruments regarding outcomes of clinical ethics support in general and regarding Moral Case Deliberation (MCD) in particular. There also is a lack of clarity and consensuses regarding which MCD outcomes are beneficial. In addition, MCD outcomes might be context-sensitive. Against this background, there is a need for a standardised but flexible outcome evaluation instrument. The aim of this study was to develop a multi-contextual evaluation instrument measuring health care providers’ experiences and perceived importance of outcomes of Moral Case Deliberation. Methods A multi-item instrument for assessing outcomes of Moral Case Deliberation (MCD) was constructed through an iterative process, founded on a literature review and modified through a multistep review by ethicists and health care providers. The instrument measures perceived importance of outcomes before and after MCD, as well as experienced outcomes during MCD and in daily work. A purposeful sample of 86 European participants contributed to a Delphi panel and content validity testing. The Delphi panel (n = 13), consisting of ethicists and ethics researchers, participated in three Delphi-rounds. Health care providers (n = 73) participated in the content validity testing through ‘think-aloud’ interviews and a method using Content Validity Index. Results The development process resulted in the European Moral Case Deliberation Outcomes Instrument (Euro-MCD), which consists of two sections, one to be completed before a participant’s first MCD and the other after completing multiple MCDs. The instrument contains a few open-ended questions and 26 specific items with a corresponding rating/response scale representing various MCD outcomes. The items were categorised into the following six domains: Enhanced emotional support, Enhanced collaboration, Improved moral reflexivity, Improved moral attitude, Improvement on organizational level and Concrete results. Conclusions A tentative instrument has been developed that seems to cover main outcomes of Moral Case Deliberation. The next step will be to test the Euro-MCD in a field study. PMID:24712735

Outcomes of moral case deliberation--the development of an evaluation instrument for clinical ethics support (the Euro-MCD).

PubMed

Svantesson, Mia; Karlsson, Jan; Boitte, Pierre; Schildman, Jan; Dauwerse, Linda; Widdershoven, Guy; Pedersen, Reidar; Huisman, Martijn; Molewijk, Bert

2014-04-08

Clinical ethics support, in particular Moral Case Deliberation, aims to support health care providers to manage ethically difficult situations. However, there is a lack of evaluation instruments regarding outcomes of clinical ethics support in general and regarding Moral Case Deliberation (MCD) in particular. There also is a lack of clarity and consensuses regarding which MCD outcomes are beneficial. In addition, MCD outcomes might be context-sensitive. Against this background, there is a need for a standardised but flexible outcome evaluation instrument. The aim of this study was to develop a multi-contextual evaluation instrument measuring health care providers' experiences and perceived importance of outcomes of Moral Case Deliberation. A multi-item instrument for assessing outcomes of Moral Case Deliberation (MCD) was constructed through an iterative process, founded on a literature review and modified through a multistep review by ethicists and health care providers. The instrument measures perceived importance of outcomes before and after MCD, as well as experienced outcomes during MCD and in daily work. A purposeful sample of 86 European participants contributed to a Delphi panel and content validity testing. The Delphi panel (n = 13), consisting of ethicists and ethics researchers, participated in three Delphi-rounds. Health care providers (n = 73) participated in the content validity testing through 'think-aloud' interviews and a method using Content Validity Index. The development process resulted in the European Moral Case Deliberation Outcomes Instrument (Euro-MCD), which consists of two sections, one to be completed before a participant's first MCD and the other after completing multiple MCDs. The instrument contains a few open-ended questions and 26 specific items with a corresponding rating/response scale representing various MCD outcomes. The items were categorised into the following six domains: Enhanced emotional support, Enhanced collaboration, Improved moral reflexivity, Improved moral attitude, Improvement on organizational level and Concrete results. A tentative instrument has been developed that seems to cover main outcomes of Moral Case Deliberation. The next step will be to test the Euro-MCD in a field study.

Validation of Satellite-Based Objective Overshooting Cloud-Top Detection Methods Using CloudSat Cloud Profiling Radar Observations

NASA Technical Reports Server (NTRS)

Bedka, Kristopher M.; Dworak, Richard; Brunner, Jason; Feltz, Wayne

2012-01-01

Two satellite infrared-based overshooting convective cloud-top (OT) detection methods have recently been described in the literature: 1) the 11-mm infrared window channel texture (IRW texture) method, which uses IRW channel brightness temperature (BT) spatial gradients and thresholds, and 2) the water vapor minus IRW BT difference (WV-IRW BTD). While both methods show good performance in published case study examples, it is important to quantitatively validate these methods relative to overshooting top events across the globe. Unfortunately, no overshooting top database currently exists that could be used in such study. This study examines National Aeronautics and Space Administration CloudSat Cloud Profiling Radar data to develop an OT detection validation database that is used to evaluate the IRW-texture and WV-IRW BTD OT detection methods. CloudSat data were manually examined over a 1.5-yr period to identify cases in which the cloud top penetrates above the tropopause height defined by a numerical weather prediction model and the surrounding cirrus anvil cloud top, producing 111 confirmed overshooting top events. When applied to Moderate Resolution Imaging Spectroradiometer (MODIS)-based Geostationary Operational Environmental Satellite-R Series (GOES-R) Advanced Baseline Imager proxy data, the IRW-texture (WV-IRW BTD) method offered a 76% (96%) probability of OT detection (POD) and 16% (81%) false-alarm ratio. Case study examples show that WV-IRW BTD.0 K identifies much of the deep convective cloud top, while the IRW-texture method focuses only on regions with a spatial scale near that of commonly observed OTs. The POD decreases by 20% when IRW-texture is applied to current geostationary imager data, highlighting the importance of imager spatial resolution for observing and detecting OT regions.

GIMDA: Graphlet interaction-based MiRNA-disease association prediction.

PubMed

Chen, Xing; Guan, Na-Na; Li, Jian-Qiang; Yan, Gui-Ying

2018-03-01

MicroRNAs (miRNAs) have been confirmed to be closely related to various human complex diseases by many experimental studies. It is necessary and valuable to develop powerful and effective computational models to predict potential associations between miRNAs and diseases. In this work, we presented a prediction model of Graphlet Interaction for MiRNA-Disease Association prediction (GIMDA) by integrating the disease semantic similarity, miRNA functional similarity, Gaussian interaction profile kernel similarity and the experimentally confirmed miRNA-disease associations. The related score of a miRNA to a disease was calculated by measuring the graphlet interactions between two miRNAs or two diseases. The novelty of GIMDA lies in that we used graphlet interaction to analyse the complex relationships between two nodes in a graph. The AUCs of GIMDA in global and local leave-one-out cross-validation (LOOCV) turned out to be 0.9006 and 0.8455, respectively. The average result of five-fold cross-validation reached to 0.8927 ± 0.0012. In case study for colon neoplasms, kidney neoplasms and prostate neoplasms based on the database of HMDD V2.0, 45, 45, 41 of the top 50 potential miRNAs predicted by GIMDA were validated by dbDEMC and miR2Disease. Additionally, in the case study of new diseases without any known associated miRNAs and the case study of predicting potential miRNA-disease associations using HMDD V1.0, there were also high percentages of top 50 miRNAs verified by the experimental literatures. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Simultaneous LC-MS/MS determination of JWH-210, RCS-4, ∆(9)-tetrahydrocannabinol, and their main metabolites in pig and human serum, whole blood, and urine for comparing pharmacokinetic data.

PubMed

Schaefer, Nadine; Kettner, Mattias; Laschke, Matthias W; Schlote, Julia; Peters, Benjamin; Bregel, Dietmar; Menger, Michael D; Maurer, Hans H; Ewald, Andreas H; Schmidt, Peter H

2015-05-01

A series of new synthetic cannabinoids (SC) has been consumed without any toxicological testing. For example, pharmacokinetic data have to be collected from forensic toxicological case work and/or animal studies. To develop a corresponding model for assessing such data, samples of controlled pig studies with two selected SC (JWH-210, RCS-4) and, as reference, ∆(9)-tetrahydrocannabinol (THC) should be analyzed as well as those of human cases. Therefore, a method for determination of JWH-210, RCS-4, THC, and their main metabolites in pig and human serum, whole blood, and urine samples is presented. Specimens were analyzed by liquid-chromatography tandem mass spectrometry and multiple-reaction monitoring with three transitions per compound. Full validation was carried out for the pig specimens and cross-validation for the human specimens concerning precision and bias. For the pig studies, the limits of detection were between 0.05 and 0.50 ng/mL in serum and whole blood and between 0.05 and 1.0 ng/mL in urine, the lower limits of quantification between 0.25 and 1.0 ng/mL in serum and 0.50 and 2.0 ng/mL in whole blood and urine, and the intra- and interday precision values lower than 15% and bias values within ±15%. The applicability was tested with samples taken from a pharmacokinetic pilot study with pigs following intravenous administration of a mixture of 200 μg/kg body mass dose each of JWH-210, RCS-4, and THC. The cross-validation data for human serum, whole blood, and urine showed that this approach should also be suitable for human specimens, e.g., of clinical or forensic cases.

Generator Dynamic Model Validation and Parameter Calibration Using Phasor Measurements at the Point of Connection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Zhenyu; Du, Pengwei; Kosterev, Dmitry

2013-05-01

Disturbance data recorded by phasor measurement units (PMU) offers opportunities to improve the integrity of dynamic models. However, manually tuning parameters through play-back events demands significant efforts and engineering experiences. In this paper, a calibration method using the extended Kalman filter (EKF) technique is proposed. The formulation of EKF with parameter calibration is discussed. Case studies are presented to demonstrate its validity. The proposed calibration method is cost-effective, complementary to traditional equipment testing for improving dynamic model quality.

Validation of the NCC Code for Staged Transverse Injection and Computations for a RBCC Combustor

NASA Technical Reports Server (NTRS)

Ajmani, Kumud; Liu, Nan-Suey

2005-01-01

The NCC code was validated for a case involving staged transverse injection into Mach 2 flow behind a rearward facing step. Comparisons with experimental data and with solutions from the FPVortex code was then used to perform computations to study fuel-air mixing for the combustor of a candidate rocket based combined cycle engine geometry. Comparisons with a one-dimensional analysis and a three-dimensional code (VULCAN) were performed to assess the qualitative and quantitative performance of the NCC solver.

Near-Infrared Spectroscopy to Reduce Prophylactic Fasciotomies for and Missed Cases of Acute Compartment Syndrome in Soldiers Injured in OEF/OIF

DTIC Science & Technology

2014-10-01

validate the accuracy and reliability of a specific NIRS sensor (Equanox, Nonin , Inc, Plymouth, MN) in diagnosing acute compartment syndrome in...clinical studies (the Nonin EquanoxTM 7600 oximeter) is for monitoring regional tissue oxygenation. This device has been validated and is currently...between Nonin , Inc and J+M Shuler – Completed in Year 2 4b: Begin reduction to practice process – Completed in Period 4. The process of reducing to

Face and Content Validity of the MacArthur Competence Assessment Tool for the Treatment of Iranian Patients.

PubMed

Saber, Ali; Tabatabaei, Seyed Mahmoud; Akasheh, Godarz; Sehat, Mojtaba; Zanjani, Zahra; Larijani, Bagher

2017-01-01

There is not a valid Persian tool for measuring the decision-making competency of patients. The aim of this study is to evaluate the face and content validity of the MacArthur Competence Assessment Tool for the treatment of Iranian Persian-speaking patients. To assess the validity of the Persian version of the tool, a self-administrated questionnaire was designed. The Lawshe method was also used for assessing each item. Content validity ratio (CVR) and content validity index (CVI) were used to assess the content validity quantitatively. According to the experts' judgment, questions with a CVR ≥0.62 and CVR <0.62 were maintainable and unmaintainable, respectively. The questions were designed in a manner to achieve the desirable result (CVR ≥0.62). The CVI scale (S-CVI) and CVI (S-CVI/Ave) were 0.94 (higher than 0.79). Thus, the content validity was confirmed. Since capacity assessments are usually based on physician's subjective judgment, they are likely to bias and therefore, with this suitably validated tool, we can improve judgment of physicians and health-care providers in out- and in-patient cases.

Multireader multicase reader studies with binary agreement data: simulation, analysis, validation, and sizing.

PubMed

Chen, Weijie; Wunderlich, Adam; Petrick, Nicholas; Gallas, Brandon D

2014-10-01

We treat multireader multicase (MRMC) reader studies for which a reader's diagnostic assessment is converted to binary agreement (1: agree with the truth state, 0: disagree with the truth state). We present a mathematical model for simulating binary MRMC data with a desired correlation structure across readers, cases, and two modalities, assuming the expected probability of agreement is equal for the two modalities ([Formula: see text]). This model can be used to validate the coverage probabilities of 95% confidence intervals (of [Formula: see text], [Formula: see text], or [Formula: see text] when [Formula: see text]), validate the type I error of a superiority hypothesis test, and size a noninferiority hypothesis test (which assumes [Formula: see text]). To illustrate the utility of our simulation model, we adapt the Obuchowski-Rockette-Hillis (ORH) method for the analysis of MRMC binary agreement data. Moreover, we use our simulation model to validate the ORH method for binary data and to illustrate sizing in a noninferiority setting. Our software package is publicly available on the Google code project hosting site for use in simulation, analysis, validation, and sizing of MRMC reader studies with binary agreement data.

Multireader multicase reader studies with binary agreement data: simulation, analysis, validation, and sizing

PubMed Central

Chen, Weijie; Wunderlich, Adam; Petrick, Nicholas; Gallas, Brandon D.

2014-01-01

Abstract. We treat multireader multicase (MRMC) reader studies for which a reader’s diagnostic assessment is converted to binary agreement (1: agree with the truth state, 0: disagree with the truth state). We present a mathematical model for simulating binary MRMC data with a desired correlation structure across readers, cases, and two modalities, assuming the expected probability of agreement is equal for the two modalities (P1=P2). This model can be used to validate the coverage probabilities of 95% confidence intervals (of P1, P2, or P1−P2 when P1−P2=0), validate the type I error of a superiority hypothesis test, and size a noninferiority hypothesis test (which assumes P1=P2). To illustrate the utility of our simulation model, we adapt the Obuchowski–Rockette–Hillis (ORH) method for the analysis of MRMC binary agreement data. Moreover, we use our simulation model to validate the ORH method for binary data and to illustrate sizing in a noninferiority setting. Our software package is publicly available on the Google code project hosting site for use in simulation, analysis, validation, and sizing of MRMC reader studies with binary agreement data. PMID:26158051

Zig-zag tape influence in NREL Phase VI wind turbine

NASA Astrophysics Data System (ADS)

Gomez-Iradi, Sugoi; Munduate, Xabier

2014-06-01

Two bladed 10 metre diameter wind turbine was tested in the 24.4m × 36.6m NASA-Ames wind tunnel (Phase VI). These experiments have been extensively used for validation purposes for CFD and other engineering tools. The free transition case (S), has been, and is, the most employed one for validation purposes, and consist in a 3° pitch case with a rotational speed of 72rpm upwind configuration with and without yaw misalignment. However, there is another less visited case (M) where identical configuration was tested but with the inclusion of a zig-zag tape. This was called transition fixed sequence. This paper shows the differences between the free and the fix transition cases, that should be more appropriate for comparison with fully turbulent simulations. Steady k-ω SST fully turbulent computations performed with WMB CFD method are compared with the experiments showing, better predictions in the attached flow region when it is compared with the transition fixed experiments. This work wants to prove the utility of M case (transition fixed) and show its differences respect the S case (free transition) for validation purposes.

External validation of Vascular Study Group of New England risk predictive model of mortality after elective abdominal aorta aneurysm repair in the Vascular Quality Initiative and comparison against established models.

PubMed

Eslami, Mohammad H; Rybin, Denis V; Doros, Gheorghe; Siracuse, Jeffrey J; Farber, Alik

2018-01-01

The purpose of this study is to externally validate a recently reported Vascular Study Group of New England (VSGNE) risk predictive model of postoperative mortality after elective abdominal aortic aneurysm (AAA) repair and to compare its predictive ability across different patients' risk categories and against the established risk predictive models using the Vascular Quality Initiative (VQI) AAA sample. The VQI AAA database (2010-2015) was queried for patients who underwent elective AAA repair. The VSGNE cases were excluded from the VQI sample. The external validation of a recently published VSGNE AAA risk predictive model, which includes only preoperative variables (age, gender, history of coronary artery disease, chronic obstructive pulmonary disease, cerebrovascular disease, creatinine levels, and aneurysm size) and planned type of repair, was performed using the VQI elective AAA repair sample. The predictive value of the model was assessed via the C-statistic. Hosmer-Lemeshow method was used to assess calibration and goodness of fit. This model was then compared with the Medicare, Vascular Governance Northwest model, and Glasgow Aneurysm Score for predicting mortality in VQI sample. The Vuong test was performed to compare the model fit between the models. Model discrimination was assessed in different risk group VQI quintiles. Data from 4431 cases from the VSGNE sample with the overall mortality rate of 1.4% was used to develop the model. The internally validated VSGNE model showed a very high discriminating ability in predicting mortality (C = 0.822) and good model fit (Hosmer-Lemeshow P = .309) among the VSGNE elective AAA repair sample. External validation on 16,989 VQI cases with an overall 0.9% mortality rate showed very robust predictive ability of mortality (C = 0.802). Vuong tests yielded a significant fit difference favoring the VSGNE over then Medicare model (C = 0.780), Vascular Governance Northwest (0.774), and Glasgow Aneurysm Score (0.639). Across the 5 risk quintiles, the VSGNE model predicted observed mortality significantly with great accuracy. This simple VSGNE AAA risk predictive model showed very high discriminative ability in predicting mortality after elective AAA repair among a large external independent sample of AAA cases performed by a diverse array of physicians nationwide. The risk score based on this simple VSGNE model can reliably stratify patients according to their risk of mortality after elective AAA repair better than other established models. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Forecasting the Incidence of Dementia and Dementia-Related Outpatient Visits With Google Trends: Evidence From Taiwan.

PubMed

Wang, Ho-Wei; Chen, Duan-Rung; Yu, Hsiao-Wei; Chen, Ya-Mei

2015-11-19

Google Trends has demonstrated the capability to both monitor and predict epidemic outbreaks. The connection between Internet searches for dementia information and dementia incidence and dementia-related outpatient visits remains unknown. This study aimed to determine whether Google Trends could provide insight into trends in dementia incidence and related outpatient visits in Taiwan. We investigated and validated the local search terms that would be the best predictors of new dementia cases and outpatient visits. We further evaluated the nowcasting (ie, forecasting the present) and forecasting effects of Google Trends search trends for new dementia cases and outpatient visits. The long-term goal is to develop a surveillance system to help early detection and interventions for dementia in Taiwan. This study collected (1) dementia data from Taiwan's National Health Insurance Research Database and (2) local Internet search data from Google Trends, both from January 2009 to December 2011. We investigated and validated search terms that would be the best predictors of new dementia cases and outpatient visits. We then evaluated both the nowcasting and the forecasting effects of Google Trends search trends through cross-correlation analysis of the dementia incidence and outpatient visit data with the Google Trends data. The search term "dementia + Alzheimer's disease" demonstrated a 3-month lead effect for new dementia cases and a 6-month lead effect for outpatient visits (r=.503, P=.002; r=.431, P=.009, respectively). When gender was included in the analysis, the search term "dementia" showed 6-month predictive power for new female dementia cases (r=.520, P=.001), but only a nowcasting effect for male cases (r=.430, P=.009). The search term "neurology" demonstrated a 3-month leading effect for new dementia cases (r=.433, P=.008), for new male dementia cases (r=.434, P=.008), and for outpatient visits (r=.613, P<.001). Google Trends established a plausible relationship between search terms and new dementia cases and dementia-related outpatient visits in Taiwan. This data may allow the health care system in Taiwan to prepare for upcoming outpatient and dementia screening visits. In addition, the validated search term results can be used to provide caregivers with caregiving-related health, skills, and social welfare information by embedding dementia-related search keywords in relevant online articles.

Forecasting the Incidence of Dementia and Dementia-Related Outpatient Visits With Google Trends: Evidence From Taiwan

PubMed Central

2015-01-01

Background Google Trends has demonstrated the capability to both monitor and predict epidemic outbreaks. The connection between Internet searches for dementia information and dementia incidence and dementia-related outpatient visits remains unknown. Objective This study aimed to determine whether Google Trends could provide insight into trends in dementia incidence and related outpatient visits in Taiwan. We investigated and validated the local search terms that would be the best predictors of new dementia cases and outpatient visits. We further evaluated the nowcasting (ie, forecasting the present) and forecasting effects of Google Trends search trends for new dementia cases and outpatient visits. The long-term goal is to develop a surveillance system to help early detection and interventions for dementia in Taiwan. Methods This study collected (1) dementia data from Taiwan’s National Health Insurance Research Database and (2) local Internet search data from Google Trends, both from January 2009 to December 2011. We investigated and validated search terms that would be the best predictors of new dementia cases and outpatient visits. We then evaluated both the nowcasting and the forecasting effects of Google Trends search trends through cross-correlation analysis of the dementia incidence and outpatient visit data with the Google Trends data. Results The search term “dementia + Alzheimer’s disease” demonstrated a 3-month lead effect for new dementia cases and a 6-month lead effect for outpatient visits (r=.503, P=.002; r=.431, P=.009, respectively). When gender was included in the analysis, the search term “dementia” showed 6-month predictive power for new female dementia cases (r=.520, P=.001), but only a nowcasting effect for male cases (r=.430, P=.009). The search term “neurology” demonstrated a 3-month leading effect for new dementia cases (r=.433, P=.008), for new male dementia cases (r=.434, P=.008), and for outpatient visits (r=.613, P<.001). Conclusions Google Trends established a plausible relationship between search terms and new dementia cases and dementia-related outpatient visits in Taiwan. This data may allow the health care system in Taiwan to prepare for upcoming outpatient and dementia screening visits. In addition, the validated search term results can be used to provide caregivers with caregiving-related health, skills, and social welfare information by embedding dementia-related search keywords in relevant online articles. PMID:26586281

Analytic Validation of Immunohistochemistry Assays: New Benchmark Data From a Survey of 1085 Laboratories.

PubMed

Stuart, Lauren N; Volmar, Keith E; Nowak, Jan A; Fatheree, Lisa A; Souers, Rhona J; Fitzgibbons, Patrick L; Goldsmith, Jeffrey D; Astles, J Rex; Nakhleh, Raouf E

2017-09-01

- A cooperative agreement between the College of American Pathologists (CAP) and the United States Centers for Disease Control and Prevention was undertaken to measure laboratories' awareness and implementation of an evidence-based laboratory practice guideline (LPG) on immunohistochemical (IHC) validation practices published in 2014. - To establish new benchmark data on IHC laboratory practices. - A 2015 survey on IHC assay validation practices was sent to laboratories subscribed to specific CAP proficiency testing programs and to additional nonsubscribing laboratories that perform IHC testing. Specific questions were designed to capture laboratory practices not addressed in a 2010 survey. - The analysis was based on responses from 1085 laboratories that perform IHC staining. Ninety-six percent (809 of 844) always documented validation of IHC assays. Sixty percent (648 of 1078) had separate procedures for predictive and nonpredictive markers, 42.7% (220 of 515) had procedures for laboratory-developed tests, 50% (349 of 697) had procedures for testing cytologic specimens, and 46.2% (363 of 785) had procedures for testing decalcified specimens. Minimum case numbers were specified by 85.9% (720 of 838) of laboratories for nonpredictive markers and 76% (584 of 768) for predictive markers. Median concordance requirements were 95% for both types. For initial validation, 75.4% (538 of 714) of laboratories adopted the 20-case minimum for nonpredictive markers and 45.9% (266 of 579) adopted the 40-case minimum for predictive markers as outlined in the 2014 LPG. The most common method for validation was correlation with morphology and expected results. Laboratories also reported which assay changes necessitated revalidation and their minimum case requirements. - Benchmark data on current IHC validation practices and procedures may help laboratories understand the issues and influence further refinement of LPG recommendations.

The Use of CASES-97 Observations to Assess and Parameterize the Impact of Land-Surface Heterogeneity on Area-Average Surface Heat Fluxes for Large-Scale Coupled Atmosphere-Hydrology Models

NASA Technical Reports Server (NTRS)

Chen, Fei; Yates, David; LeMone, Margaret

2001-01-01

To understand the effects of land-surface heterogeneity and the interactions between the land-surface and the planetary boundary layer at different scales, we develop a multiscale data set. This data set, based on the Cooperative Atmosphere-Surface Exchange Study (CASES97) observations, includes atmospheric, surface, and sub-surface observations obtained from a dense observation network covering a large region on the order of 100 km. We use this data set to drive three land-surface models (LSMs) to generate multi-scale (with three resolutions of 1, 5, and 10 kilometers) gridded surface heat flux maps for the CASES area. Upon validating these flux maps with measurements from surface station and aircraft, we utilize them to investigate several approaches for estimating the area-integrated surface heat flux for the CASES97 domain of 71x74 square kilometers, which is crucial for land surface model development/validation and area water and energy budget studies. This research is aimed at understanding the relative contribution of random turbulence versus organized mesoscale circulations to the area-integrated surface flux at the scale of 100 kilometers, and identifying the most important effective parameters for characterizing the subgrid-scale variability for large-scale atmosphere-hydrology models.

A case definition and photographic screening tool for the facial phenotype of fetal alcohol syndrome.

PubMed

Astley, S J; Clarren, S K

1996-07-01

The purpose of this study was to demonstrate that a quantitative, multivariate case definition of the fetal alcohol syndrome (FAS) facial phenotype could be derived from photographs of individuals with FAS and to demonstrate how this case definition and photographic approach could be used to develop efficient, accurate, and precise screening tools, diagnostic aids, and possibly surveillance tools. Frontal facial photographs of 42 subjects (from birth to 27 years of age) with FAS were matched to 84 subjects without FAS. The study population was randomly divided in half. Group 1 was used to identify the facial features that best differentiated individuals with and without FAS. Group 2 was used for cross validation. In group 1, stepwise discriminant analysis identified three facial features (reduced palpebral fissure length/inner canthal distance ratio, smooth philtrum, and thin upper lip) as the cluster of features that differentiated individuals with and without FAS in groups 1 and 2 with 100% accuracy. Sensitivity and specificity were unaffected by race, gender, and age. The phenotypic case definition derived from photographs accurately distinguished between individuals with and without FAS, demonstrating the potential of this approach for developing screening, diagnostic, and surveillance tools. Further evaluation of the validity and generalizability of this method will be needed.

Response of Ocean Circulation to Different Wind Forcing in Puerto Rico and US Virgin Islands

NASA Astrophysics Data System (ADS)

Solano, Miguel; Garcia, Edgardo; Leonardi, Stafano; Canals, Miguel; Capella, Jorge

2013-11-01

The response of the ocean circulation to various wind forcing products has been studied using the Regional Ocean Modeling System. The computational domain includes the main islands of Puerto Rico, Saint John and Saint Thomas, located on the continental shelf dividing the Caribbean Sea and the Atlantic Ocean. Data for wind forcing is provided by an anemometer located in a moored buoy, the Coupled Ocean-Atmosphere Mesoscale Prediction System (COAMPS) model and the National Digital Forecast Database (NDFD). Hindcast simulations have been validated using hydrographic data at different locations in the area of study. Three cases are compared to quantify the impact of high resolution wind forcing on the ocean circulation and the vertical structure of salinity, temperature and velocity. In the first case a constant wind velocity field is used to force the model as measured by an anemometer on top of a buoy. In the second case, a forcing field provided by the Navy's COAMPS model is used and in the third case, winds are taken from NDFD in collaboration with the National Centers for Environmental Prediction. Validated results of ocean currents against data from Acoustic Doppler Current Profilers at different locations show better agreement using high resolution wind data as expected. Thanks to CariCOOS and NOAA.

Should Controls With Respiratory Symptoms Be Excluded From Case-Control Studies of Pneumonia Etiology? Reflections From the PERCH Study

PubMed Central

Hammitt, Laura L.; Deloria Knoll, Maria; Baggett, Henry C.; Brooks, W. Abdullah; Howie, Stephen R. C.; Kotloff, Karen L.; Levine, Orin S.; Madhi, Shabir A.; Murdoch, David R.; Scott, J. Anthony G.; Thea, Donald M.; Driscoll, Amanda J.; Karron, Ruth A.; Park, Daniel E.; Prosperi, Christine; Zeger, Scott L.; O’Brien, Katherine L.; Feikin, Daniel R.; O’Brien, Katherine L.; Levine, Orin S.; Knoll, Maria Deloria; Feikin, Daniel R.; DeLuca, Andrea N.; Driscoll, Amanda J.; Fu, Wei; Hammitt, Laura L.; Higdon, Melissa M.; Kagucia, E. Wangeci; Karron, Ruth A.; Li, Mengying; Park, Daniel E.; Prosperi, Christine; Wu, Zhenke; Zeger, Scott L.; Watson, Nora L.; Crawley, Jane; Murdoch, David R.; Brooks, W. Abdullah; Endtz, Hubert P.; Zaman, Khalequ; Goswami, Doli; Hossain, Lokman; Jahan, Yasmin; Ashraf, Hasan; Howie, Stephen R. C.; Ebruke, Bernard E.; Antonio, Martin; McLellan, Jessica; Machuka, Eunice; Shamsul, Arifin; Zaman, Syed M.A.; Mackenzie, Grant; Scott, J. Anthony G.; Awori, Juliet O.; Morpeth, Susan C.; Kamau, Alice; Kazungu, Sidi; Kotloff, Karen L.; Tapia, Milagritos D.; Sow, Samba O.; Sylla, Mamadou; Tamboura, Boubou; Onwuchekwa, Uma; Kourouma, Nana; Toure, Aliou; Madhi, Shabir A.; Moore, David P.; Adrian, Peter V.; Baillie, Vicky L.; Kuwanda, Locadiah; Mudau, Azwifarwi; Groome, Michelle J.; Baggett, Henry C.; Thamthitiwat, Somsak; Maloney, Susan A.; Bunthi, Charatdao; Rhodes, Julia; Sawatwong, Pongpun; Akarasewi, Pasakorn; Thea, Donald M.; Mwananyanda, Lawrence; Chipeta, James; Seidenberg, Phil; Mwansa, James; wa Somwe, Somwe; Kwenda, Geoffrey

2017-01-01

Abstract Many pneumonia etiology case-control studies exclude controls with respiratory illness from enrollment or analyses. Herein we argue that selecting controls regardless of respiratory symptoms provides the least biased estimates of pneumonia etiology. We review 3 reasons investigators may choose to exclude controls with respiratory symptoms in light of epidemiologic principles of control selection and present data from the Pneumonia Etiology Research for Child Health (PERCH) study where relevant to assess their validity. We conclude that exclusion of controls with respiratory symptoms will result in biased estimates of etiology. Randomly selected community controls, with or without respiratory symptoms, as long as they do not meet the criteria for case-defining pneumonia, are most representative of the general population from which cases arose and the least subject to selection bias. PMID:28575354

SU-E-T-131: Artificial Neural Networks Applied to Overall Survival Prediction for Patients with Periampullary Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gong, Y; Yu, J; Yeung, V

Purpose: Artificial neural networks (ANN) can be used to discover complex relations within datasets to help with medical decision making. This study aimed to develop an ANN method to predict two-year overall survival of patients with peri-ampullary cancer (PAC) following resection. Methods: Data were collected from 334 patients with PAC following resection treated in our institutional pancreatic tumor registry between 2006 and 2012. The dataset contains 14 variables including age, gender, T-stage, tumor differentiation, positive-lymph-node ratio, positive resection margins, chemotherapy, radiation therapy, and tumor histology.After censoring for two-year survival analysis, 309 patients were left, of which 44 patients (∼15%) weremore » randomly selected to form testing set. The remaining 265 cases were randomly divided into training set (211 cases, ∼80% of 265) and validation set (54 cases, ∼20% of 265) for 20 times to build 20 ANN models. Each ANN has one hidden layer with 5 units. The 20 ANN models were ranked according to their concordance index (c-index) of prediction on validation sets. To further improve prediction, the top 10% of ANN models were selected, and their outputs averaged for prediction on testing set. Results: By random division, 44 cases in testing set and the remaining 265 cases have approximately equal two-year survival rates, 36.4% and 35.5% respectively. The 20 ANN models, which were trained and validated on the 265 cases, yielded mean c-indexes as 0.59 and 0.63 on validation sets and the testing set, respectively. C-index was 0.72 when the two best ANN models (top 10%) were used in prediction on testing set. The c-index of Cox regression analysis was 0.63. Conclusion: ANN improved survival prediction for patients with PAC. More patient data and further analysis of additional factors may be needed for a more robust model, which will help guide physicians in providing optimal post-operative care. This project was supported by PA CURE Grant.« less

Development and validation of a case definition for epilepsy for use with administrative health data.

PubMed

Reid, Aylin Y; St Germaine-Smith, Christine; Liu, Mingfu; Sadiq, Shahnaz; Quan, Hude; Wiebe, Samuel; Faris, Peter; Dean, Stafford; Jetté, Nathalie

2012-12-01

The objective of this study was to develop and validate coding algorithms for epilepsy using ICD-coded inpatient claims, physician claims, and emergency room (ER) visits. 720/2049 charts from 2003 and 1533/3252 charts from 2006 were randomly selected for review from 13 neurologists' practices as the "gold standard" for diagnosis. Epilepsy status in each chart was determined by 2 trained physicians. The optimal algorithm to identify epilepsy cases was developed by linking the reviewed charts with three administrative databases (ICD 9 and 10 data from 2000 to 2008) including hospital discharges, ER visits and physician claims in a Canadian health region. Accepting chart review data as the gold standard, we calculated sensitivity, specificity, positive, and negative predictive value for each ICD-9 and ICD-10 administrative data algorithm (case definitions). Of 18 algorithms assessed, the most accurate algorithm to identify epilepsy cases was "2 physician claims or 1 hospitalization in 2 years coded" (ICD-9 345 or G40/G41) and the most sensitive algorithm was "1 physician clam or 1 hospitalization or 1 ER visit in 2 years." Accurate and sensitive case definitions are available for research requiring the identification of epilepsy cases in administrative health data. Copyright © 2012 Elsevier B.V. All rights reserved.

Conflicting Discourses in Qualitative Research: The Search for Divergent Data within Cases

ERIC Educational Resources Information Center

Antin, Tamar M. J.; Constantine, Norman A.; Hunt, Geoffrey

2015-01-01

The search for disconfirming evidence, or negative cases, is often considered a valuable strategy for assessing the credibility or validity of qualitative research claims. This article draws on a multimethod qualitative research project to illustrate how a search for disconfirming evidence evolved from a check on the validity of findings to a…

Updating Risk Prediction Tools: A Case Study in Prostate Cancer

PubMed Central

Ankerst, Donna P.; Koniarski, Tim; Liang, Yuanyuan; Leach, Robin J.; Feng, Ziding; Sanda, Martin G.; Partin, Alan W.; Chan, Daniel W; Kagan, Jacob; Sokoll, Lori; Wei, John T; Thompson, Ian M.

2013-01-01

Online risk prediction tools for common cancers are now easily accessible and widely used by patients and doctors for informed decision-making concerning screening and diagnosis. A practical problem is as cancer research moves forward and new biomarkers and risk factors are discovered, there is a need to update the risk algorithms to include them. Typically the new markers and risk factors cannot be retrospectively measured on the same study participants used to develop the original prediction tool, necessitating the merging of a separate study of different participants, which may be much smaller in sample size and of a different design. Validation of the updated tool on a third independent data set is warranted before the updated tool can go online. This article reports on the application of Bayes rule for updating risk prediction tools to include a set of biomarkers measured in an external study to the original study used to develop the risk prediction tool. The procedure is illustrated in the context of updating the online Prostate Cancer Prevention Trial Risk Calculator to incorporate the new markers %freePSA and [−2]proPSA measured on an external case control study performed in Texas, U.S.. Recent state-of-the art methods in validation of risk prediction tools and evaluation of the improvement of updated to original tools are implemented using an external validation set provided by the U.S. Early Detection Research Network. PMID:22095849

Updating risk prediction tools: a case study in prostate cancer.

PubMed

Ankerst, Donna P; Koniarski, Tim; Liang, Yuanyuan; Leach, Robin J; Feng, Ziding; Sanda, Martin G; Partin, Alan W; Chan, Daniel W; Kagan, Jacob; Sokoll, Lori; Wei, John T; Thompson, Ian M

2012-01-01

Online risk prediction tools for common cancers are now easily accessible and widely used by patients and doctors for informed decision-making concerning screening and diagnosis. A practical problem is as cancer research moves forward and new biomarkers and risk factors are discovered, there is a need to update the risk algorithms to include them. Typically, the new markers and risk factors cannot be retrospectively measured on the same study participants used to develop the original prediction tool, necessitating the merging of a separate study of different participants, which may be much smaller in sample size and of a different design. Validation of the updated tool on a third independent data set is warranted before the updated tool can go online. This article reports on the application of Bayes rule for updating risk prediction tools to include a set of biomarkers measured in an external study to the original study used to develop the risk prediction tool. The procedure is illustrated in the context of updating the online Prostate Cancer Prevention Trial Risk Calculator to incorporate the new markers %freePSA and [-2]proPSA measured on an external case-control study performed in Texas, U.S.. Recent state-of-the art methods in validation of risk prediction tools and evaluation of the improvement of updated to original tools are implemented using an external validation set provided by the U.S. Early Detection Research Network. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The 'relics of Joan of Arc': a forensic multidisciplinary analysis.

PubMed

Charlier, P; Poupon, J; Eb, A; De Mazancourt, P; Gilbert, T; Huynh-Charlier, I; Loublier, Y; Verhille, A M; Moulheirat, C; Patou-Mathis, M; Robbiola, L; Montagut, R; Masson, F; Etcheberry, A; Brun, L; Willerslev, E; de la Grandmaison, G Lorin; Durigon, M

2010-01-30

Archaeological remains can provide concrete cases, making it possible to develop, refine or validate medico-legal techniques. In the case of the so-called 'Joan of Arc's relics' (a group of bone and archaeological remains known as the 'Bottle of Chinon'), 14 specialists analysed the samples such as a cadaver X of carbonised aspect: forensic anthropologist, medical examiners, pathologists, geneticists, radiologist, biochemists, palynologists, zoologist and archaeologist. Materials, methods and results of this study are presented here. This study aims to offer an exploitable methodology for the modern medico-legal cases of small quantities of human bones of carbonised aspect. 2009 Elsevier Ireland Ltd. All rights reserved.

Summary of EASM Turbulence Models in CFL3D With Validation Test Cases

NASA Technical Reports Server (NTRS)

Rumsey, Christopher L.; Gatski, Thomas B.

2003-01-01

This paper summarizes the Explicit Algebraic Stress Model in k-omega form (EASM-ko) and in k-epsilon form (EASM-ke) in the Reynolds-averaged Navier-Stokes code CFL3D. These models have been actively used over the last several years in CFL3D, and have undergone some minor modifications during that time. Details of the equations and method for coding the latest versions of the models are given, and numerous validation cases are presented. This paper serves as a validation archive for these models.

The Coach-Athlete Relationship Questionnaire (CART-Q): development and initial validation.

PubMed

Jowett, Sophia; Ntoumanis, Nikos

2004-08-01

The purpose of the present study was to develop and validate a self-report instrument that measures the nature of the coach-athlete relationship. Jowett et al.'s (Jowett & Meek, 2000; Jowett, in press) qualitative case studies and relevant literature were used to generate items for an instrument that measures affective, cognitive, and behavioral aspects of the coach-athlete relationship. Two studies were carried out in an attempt to assess content, predictive, and construct validity, as well as internal consistency, of the Coach-Athlete Relationship Questionnaire (CART-Q), using two independent British samples. Principal component analysis and confirmatory factor analysis were used to reduce the number of items, identify principal components, and confirm the latent structure of the CART-Q. Results supported the multidimensional nature of the coach-athlete relationship. The latent structure of the CART-Q was underlined by the latent variables of coaches' and athletes' Closeness (emotions), Commitment (cognitions), and Complementarity (behaviors).

A biopsychosocial vignette for case conceptualization in dementia (VIG-Dem): development and pilot study.

PubMed

Spector, Aimee; Hebditch, Molly; Stoner, Charlotte R; Gibbor, Luke

2016-09-01

The ability to identify biological, social, and psychological issues for people with dementia is an important skill for healthcare professionals. Therefore, valid and reliable measures are needed to assess this ability. This study involves the development of a vignette style measure to capture the extent to which health professionals use "Biopsychosocial" thinking in dementia care (VIG-Dem), based on the framework of the model developed by Spector and Orrell (2010). The development process consisted of Phase 1: Developing and refining the vignettes; Phase 2: Field testing (N = 9), and Phase 3: A pilot study to assess reliability and validity (N = 131). The VIG-Dem, consisting of two vignettes with open-ended questions and a standardized scoring scheme, was developed. Evidence for the good inter-rater reliability, convergent validity, and test-retest reliability were established. The VIG-Dem has good psychometric properties and may provide a useful tool in dementia care research and practice.

Validity of peptic ulcer disease and upper gastrointestinal bleeding diagnoses in administrative databases: a systematic review protocol.

PubMed

Montedori, Alessandro; Abraha, Iosief; Chiatti, Carlos; Cozzolino, Francesco; Orso, Massimiliano; Luchetta, Maria Laura; Rimland, Joseph M; Ambrosio, Giuseppe

2016-09-15

Administrative healthcare databases are useful to investigate the epidemiology, health outcomes, quality indicators and healthcare utilisation concerning peptic ulcers and gastrointestinal bleeding, but the databases need to be validated in order to be a reliable source for research. The aim of this protocol is to perform the first systematic review of studies reporting the validation of International Classification of Diseases, 9th Revision and 10th version (ICD-9 and ICD-10) codes for peptic ulcer and upper gastrointestinal bleeding diagnoses. MEDLINE, EMBASE, Web of Science and the Cochrane Library databases will be searched, using appropriate search strategies. We will include validation studies that used administrative data to identify peptic ulcer disease and upper gastrointestinal bleeding diagnoses or studies that evaluated the validity of peptic ulcer and upper gastrointestinal bleeding codes in administrative data. The following inclusion criteria will be used: (a) the presence of a reference standard case definition for the diseases of interest; (b) the presence of at least one test measure (eg, sensitivity, etc) and (c) the use of an administrative database as a source of data. Pairs of reviewers will independently abstract data using standardised forms and will evaluate quality using the checklist of the Standards for Reporting of Diagnostic Accuracy (STARD) criteria. This systematic review protocol has been produced in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol (PRISMA-P) 2015 statement. Ethics approval is not required given that this is a protocol for a systematic review. We will submit results of this study to a peer-reviewed journal for publication. The results will serve as a guide for researchers validating administrative healthcare databases to determine appropriate case definitions for peptic ulcer disease and upper gastrointestinal bleeding, as well as to perform outcome research using administrative healthcare databases of these conditions. CRD42015029216. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Diagnostic performance of major depression disorder case-finding instruments used among mothers of young children in the United States: A systematic review.

PubMed

Owora, Arthur H; Carabin, Hélène; Reese, Jessica; Garwe, Tabitha

2016-09-01

Growing recognition of the interrelated negative outcomes associated with major depression disorder (MDD) among mothers and their children has led to renewed public health interest in the early identification and treatment of maternal MDD. Healthcare providers, however, remain unsure of the validity of existing case-finding instruments. We conducted a systematic review to identify the most valid maternal MDD case-finding instrument used in the United States. We identified articles reporting the sensitivity and specificity of MDD case-finding instruments based on Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) by systematically searching through three electronic bibliographic databases, PubMed, PsycINFO, and EMBASE, from 1994 to 2014. Study eligibility and quality were evaluated using the Standards for the Reporting of Diagnostic Accuracy studies and Quality Assessment of Diagnostic Accuracy Studies guidelines respectively. Overall, we retrieved 996 unduplicated articles and selected 74 for full-text review. Of these, 14 articles examining 21 different instruments were included in the systematic review. The 10 item Edinburgh Postnatal Depression Scale and Postpartum Depression Screening Scale had the most stable (lowest variation) and highest diagnostic performance during the antepartum and postpartum periods (sensitivity range: 0.63-0.94 and 0.67-0.95; specificity range: 0.83-0.98 and 0.68-0.97 respectively). Greater variation in diagnostic performance was observed among studies with higher MDD prevalence. Factors that explain greater variation in instrument diagnostic performance in study populations with higher MDD prevalence were not examined. Findings suggest that the diagnostic performance of maternal MDD case-finding instruments is peripartum period-specific. Published by Elsevier B.V.

Derivation and external validation of a case mix model for the standardized reporting of 30-day stroke mortality rates.

PubMed

Bray, Benjamin D; Campbell, James; Cloud, Geoffrey C; Hoffman, Alex; James, Martin; Tyrrell, Pippa J; Wolfe, Charles D A; Rudd, Anthony G

2014-11-01

Case mix adjustment is required to allow valid comparison of outcomes across care providers. However, there is a lack of externally validated models suitable for use in unselected stroke admissions. We therefore aimed to develop and externally validate prediction models to enable comparison of 30-day post-stroke mortality outcomes using routine clinical data. Models were derived (n=9000 patients) and internally validated (n=18 169 patients) using data from the Sentinel Stroke National Audit Program, the national register of acute stroke in England and Wales. External validation (n=1470 patients) was performed in the South London Stroke Register, a population-based longitudinal study. Models were fitted using general estimating equations. Discrimination and calibration were assessed using receiver operating characteristic curve analysis and correlation plots. Two final models were derived. Model A included age (<60, 60-69, 70-79, 80-89, and ≥90 years), National Institutes of Health Stroke Severity Score (NIHSS) on admission, presence of atrial fibrillation on admission, and stroke type (ischemic versus primary intracerebral hemorrhage). Model B was similar but included only the consciousness component of the NIHSS in place of the full NIHSS. Both models showed excellent discrimination and calibration in internal and external validation. The c-statistics in external validation were 0.87 (95% confidence interval, 0.84-0.89) and 0.86 (95% confidence interval, 0.83-0.89) for models A and B, respectively. We have derived and externally validated 2 models to predict mortality in unselected patients with acute stroke using commonly collected clinical variables. In settings where the ability to record the full NIHSS on admission is limited, the level of consciousness component of the NIHSS provides a good approximation of the full NIHSS for mortality prediction. © 2014 American Heart Association, Inc.

[Clinical decision making: Fostering critical thinking in the nursing diagnostic process through case studies].

PubMed

Müller-Staub, Maria; Stuker-Studer, Ursula

2006-10-01

Case studies, based on actual patients' situations, provide a method of clinical decision making to foster critical thinking in nurses. This paper describes the method and process of group case studies applied in continuous education settings. This method bases on Balints' case supervision and was further developed and combined with the nursing diagnostic process. A case study contains different phases: Pre-phase, selection phase, case delineation and case work. The case provider narratively tells the situation of a patient. This allows the group to analyze and cluster signs and symptoms, to state nursing diagnoses and to derive nursing interventions. Results of the case study are validated by applying the theoretical background and critical appraisal of the case provider. Learning effects of the case studies were evaluated by means of qualitative questionnaires and analyzed according to Mayring. Findings revealed the following categories: a) Patients' problems are perceived in a patient centred way, accurate nursing diagnoses are stated and effective nursing interventions implemented. b) Professional nursing tasks are more purposefully perceived and named more precise. c) Professional nursing relationship, communication and respectful behaviour with patients were perceived in differentiated ways. The theoretical framework is described in the paper "Clinical decision making and critical thinking in the nursing diagnostic process". (Müller-Staub, 2006).

The effects of recall errors and of selection bias in epidemiologic studies of mobile phone use and cancer risk.

PubMed

Vrijheid, Martine; Deltour, Isabelle; Krewski, Daniel; Sanchez, Marie; Cardis, Elisabeth

2006-07-01

This paper examines the effects of systematic and random errors in recall and of selection bias in case-control studies of mobile phone use and cancer. These sensitivity analyses are based on Monte-Carlo computer simulations and were carried out within the INTERPHONE Study, an international collaborative case-control study in 13 countries. Recall error scenarios simulated plausible values of random and systematic, non-differential and differential recall errors in amount of mobile phone use reported by study subjects. Plausible values for the recall error were obtained from validation studies. Selection bias scenarios assumed varying selection probabilities for cases and controls, mobile phone users, and non-users. Where possible these selection probabilities were based on existing information from non-respondents in INTERPHONE. Simulations used exposure distributions based on existing INTERPHONE data and assumed varying levels of the true risk of brain cancer related to mobile phone use. Results suggest that random recall errors of plausible levels can lead to a large underestimation in the risk of brain cancer associated with mobile phone use. Random errors were found to have larger impact than plausible systematic errors. Differential errors in recall had very little additional impact in the presence of large random errors. Selection bias resulting from underselection of unexposed controls led to J-shaped exposure-response patterns, with risk apparently decreasing at low to moderate exposure levels. The present results, in conjunction with those of the validation studies conducted within the INTERPHONE study, will play an important role in the interpretation of existing and future case-control studies of mobile phone use and cancer risk, including the INTERPHONE study.

Case Study: OpenSSL 2012 Validation

DTIC Science & Technology

2013-08-01

there are probably millions of users who are impacted directly, and hundreds of millions who are indirectly affected. Cryptographic libraries are...UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESSES 8. PERFORMING ORGANIZATION REPORT NUMBER D-4991 H13 -001174 Institute for Defense

Finding the Balance: Jan Kagarice, a Case Study of a Master Trombone Teacher

ERIC Educational Resources Information Center

Marston, Karen Lynn

2011-01-01

The purpose of this study was to investigate and document the pedagogical techniques practiced by Jan Kagarice, Adjunct Professor of Trombone at the University of North Texas. Given that the study of master teachers has been identified as a valid method for defining effective teaching (Duke & Simmons, 2006), the intended outcome was to…

Remote sensing and GIS-based landslide hazard analysis and cross-validation using multivariate logistic regression model on three test areas in Malaysia

NASA Astrophysics Data System (ADS)

Pradhan, Biswajeet

2010-05-01

This paper presents the results of the cross-validation of a multivariate logistic regression model using remote sensing data and GIS for landslide hazard analysis on the Penang, Cameron, and Selangor areas in Malaysia. Landslide locations in the study areas were identified by interpreting aerial photographs and satellite images, supported by field surveys. SPOT 5 and Landsat TM satellite imagery were used to map landcover and vegetation index, respectively. Maps of topography, soil type, lineaments and land cover were constructed from the spatial datasets. Ten factors which influence landslide occurrence, i.e., slope, aspect, curvature, distance from drainage, lithology, distance from lineaments, soil type, landcover, rainfall precipitation, and normalized difference vegetation index (ndvi), were extracted from the spatial database and the logistic regression coefficient of each factor was computed. Then the landslide hazard was analysed using the multivariate logistic regression coefficients derived not only from the data for the respective area but also using the logistic regression coefficients calculated from each of the other two areas (nine hazard maps in all) as a cross-validation of the model. For verification of the model, the results of the analyses were then compared with the field-verified landslide locations. Among the three cases of the application of logistic regression coefficient in the same study area, the case of Selangor based on the Selangor logistic regression coefficients showed the highest accuracy (94%), where as Penang based on the Penang coefficients showed the lowest accuracy (86%). Similarly, among the six cases from the cross application of logistic regression coefficient in other two areas, the case of Selangor based on logistic coefficient of Cameron showed highest (90%) prediction accuracy where as the case of Penang based on the Selangor logistic regression coefficients showed the lowest accuracy (79%). Qualitatively, the cross application model yields reasonable results which can be used for preliminary landslide hazard mapping.

External Validation of a Case-Mix Adjustment Model for the Standardized Reporting of 30-Day Stroke Mortality Rates in China

PubMed Central

Yu, Ping; Pan, Yuesong; Wang, Yongjun; Wang, Xianwei; Liu, Liping; Ji, Ruijun; Meng, Xia; Jing, Jing; Tong, Xu; Guo, Li; Wang, Yilong

2016-01-01

Background and Purpose A case-mix adjustment model has been developed and externally validated, demonstrating promise. However, the model has not been thoroughly tested among populations in China. In our study, we evaluated the performance of the model in Chinese patients with acute stroke. Methods The case-mix adjustment model A includes items on age, presence of atrial fibrillation on admission, National Institutes of Health Stroke Severity Scale (NIHSS) score on admission, and stroke type. Model B is similar to Model A but includes only the consciousness component of the NIHSS score. Both model A and B were evaluated to predict 30-day mortality rates in 13,948 patients with acute stroke from the China National Stroke Registry. The discrimination of the models was quantified by c-statistic. Calibration was assessed using Pearson’s correlation coefficient. Results The c-statistic of model A in our external validation cohort was 0.80 (95% confidence interval, 0.79–0.82), and the c-statistic of model B was 0.82 (95% confidence interval, 0.81–0.84). Excellent calibration was reported in the two models with Pearson’s correlation coefficient (0.892 for model A, p<0.001; 0.927 for model B, p = 0.008). Conclusions The case-mix adjustment model could be used to effectively predict 30-day mortality rates in Chinese patients with acute stroke. PMID:27846282

Improving Public Reporting and Data Validation for Complex Surgical Site Infections After Coronary Artery Bypass Graft Surgery and Hip Arthroplasty

PubMed Central

Calderwood, Michael S.; Kleinman, Ken; Murphy, Michael V.; Platt, Richard; Huang, Susan S.

2014-01-01

Background  Deep and organ/space surgical site infections (D/OS SSI) cause significant morbidity, mortality, and costs. Rates are publicly reported and increasingly used as quality metrics affecting hospital payment. Lack of standardized surveillance methods threaten the accuracy of reported data and decrease confidence in comparisons based upon these data. Methods  We analyzed data from national validation studies that used Medicare claims to trigger chart review for SSI confirmation after coronary artery bypass graft surgery (CABG) and hip arthroplasty. We evaluated code performance (sensitivity and positive predictive value) to select diagnosis codes that best identified D/OS SSI. Codes were analyzed individually and in combination. Results  Analysis included 143 patients with D/OS SSI after CABG and 175 patients with D/OS SSI after hip arthroplasty. For CABG, 9 International Classification of Diseases, 9th Revision (ICD-9) diagnosis codes identified 92% of D/OS SSI, with 1 D/OS SSI identified for every 4 cases with a diagnosis code. For hip arthroplasty, 6 ICD-9 diagnosis codes identified 99% of D/OS SSI, with 1 D/OS SSI identified for every 2 cases with a diagnosis code. Conclusions  This standardized and efficient approach for identifying D/OS SSI can be used by hospitals to improve case detection and public reporting. This method can also be used to identify potential D/OS SSI cases for review during hospital audits for data validation. PMID:25734174

The importance of establishing reliability and validity of assessment instruments for mental health problems: An example from Somali children and adolescents living in three refugee camps in Ethiopia

PubMed Central

Hall, Brian J.; Puffer, Eve; Murray, Laura K.; Ismael, Abdulkadir; Bass, Judith K.; Sim, Amanda; Bolton, Paul A.

2014-01-01

Assessing mental health problems cross-culturally for children exposed to war and violence presents a number of unique challenges. One of the most important issues is the lack of validated symptom measures to assess these problems. The present study sought to evaluate the psychometric properties of two measures to assess mental health problems: the Achenbach Youth Self-Report and the Child Posttraumatic Stress Disorder Symptom Scale. We conducted a validity study in three refugee camps in Eastern Ethiopia in the outskirts of Jijiga, the capital of the Somali region. A total of 147 child and caregiver pairs were assessed, and scores obtained were submitted to rigorous psychometric evaluation. Excellent internal consistency reliability was obtained for symptom measures for children and their caregivers. Validation of study instruments based on local case definitions was obtained for the caregivers but not consistently for the children. Sensitivity and specificity of study measures were generally low, indicating that these scales would not perform adequately as screening instruments. Combined test-retest and inter-rater reliability was low for all scales. This study illustrates the need for validation and testing of existing measures cross-culturally. Methodological implications for future cross-cultural research studies in low- and middle-income countries are discussed. PMID:24955147

Assessment of Functional Rhinoplasty with Spreader Grafting Using Acoustic Rhinomanometry and Validated Outcome Measurements

PubMed Central

Paul, Marek A.; Kamali, Parisa; Chen, Austin D.; Ibrahim, Ahmed M. S.; Wu, Winona; Becherer, Babette E.; Medin, Caroline

2018-01-01

Background: Rhinoplasty is 1 of the most common aesthetic and reconstructive plastic surgical procedures performed within the United States. Yet, data on functional reconstructive open and closed rhinoplasty procedures with or without spreader graft placement are not definitive as only a few studies have examined both validated measurable objective and subjective outcomes of spreader grafting during rhinoplasty. The aim of this study was to utilize previously validated measures to assess objective, functional outcomes in patients who underwent open and closed rhinoplasty with spreader grafting. Methods: We performed a retrospective review of consecutive rhinoplasty patients. Patients with internal nasal valve insufficiency who underwent an open and closed approach rhinoplasty between 2007 and 2016 were studied. The Cottle test and Nasal Obstruction Symptom Evaluation survey was used to assess nasal obstruction. Patient-reported symptoms were recorded. Acoustic rhinometry was performed pre- and postoperatively. Average minimal cross-sectional area of the nose was measured. Results: One hundred seventy-eight patients were reviewed over a period of 8 years. Thirty-eight patients were included in this study. Of those, 30 patients underwent closed rhinoplasty and 8 open rhinoplasty. Mean age was 36.9 ± 18.4 years. The average cross-sectional area in closed and open rhinoplasty patients increased significantly (P = 0.019). There was a functional improvement in all presented cases using the Nasal Obstruction Symptom Evaluation scale evaluation. Conclusions: Closed rhinoplasty with spreader grafting may play a significant role in the treatment of nasal valve collapse. A closed approach rhinoplasty including spreader grafting is a viable option in select cases with objective and validated functional improvement. PMID:29707440

Multimodal Navigation in Endoscopic Transsphenoidal Resection of Pituitary Tumors Using Image-Based Vascular and Cranial Nerve Segmentation: A Prospective Validation Study.

PubMed

Dolati, Parviz; Eichberg, Daniel; Golby, Alexandra; Zamani, Amir; Laws, Edward

2016-11-01

Transsphenoidal surgery (TSS) is the most common approach for the treatment of pituitary tumors. However, misdirection, vascular damage, intraoperative cerebrospinal fluid leakage, and optic nerve injuries are all well-known complications, and the risk of adverse events is more likely in less-experienced hands. This prospective study was conducted to validate the accuracy of image-based segmentation coupled with neuronavigation in localizing neurovascular structures during TSS. Twenty-five patients with a pituitary tumor underwent preoperative 3-T magnetic resonance imaging (MRI), and MRI images loaded into the navigation platform were used for segmentation and preoperative planning. After patient registration and subsequent surgical exposure, each segmented neural or vascular element was validated by manual placement of the navigation probe or Doppler probe on or as close as possible to the target. Preoperative segmentation of the internal carotid artery and cavernous sinus matched with the intraoperative endoscopic and micro-Doppler findings in all cases. Excellent correspondence between image-based segmentation and the endoscopic view was also evident at the surface of the tumor and at the tumor-normal gland interfaces. Image guidance assisted the surgeons in localizing the optic nerve and chiasm in 64% of cases. The mean accuracy of the measurements was 1.20 ± 0.21 mm. Image-based preoperative vascular and neural element segmentation, especially with 3-dimensional reconstruction, is highly informative preoperatively and potentially could assist less-experienced neurosurgeons in preventing vascular and neural injury during TSS. In addition, the accuracy found in this study is comparable to previously reported neuronavigation measurements. This preliminary study is encouraging for future prospective intraoperative validation with larger numbers of patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Development of an Evaporation Sub-model and Simulation of Multiple Droplet Impingement in Volume of Fluid Method

NASA Astrophysics Data System (ADS)

Potham, Sathya Prasad

Droplet collision and impingement on a substrate are widely observed phenomenon in many applications like spray injection of Internal Combustion Engines, spray cooling, spray painting and atomizers used in propulsion applications. Existing Lagrangian models do not provide a comprehensive picture of the outcome of these events and may involve model constants requiring experimental data for validation. Physics based models like Volume of Fluid (VOF) method involve no parametric tuning and are more accurate. The aim of this thesis is to extend the basic VOF method with an evaporation sub-model and implement in an open source Computational Fluid Dynamics (CFD) software, OpenFOAM. The new model is applied to numerically study the evaporation of spherical n-heptane droplets impinging on a hot wall at atmospheric pressure and a temperature above the Leidenfrost temperature. An additional vapor phase is introduced apart from the liquid and gas phases to understand the mixing and diffusion of vapor and gas phases. The evaporation model is validated quantitatively and qualitatively with fundamental problems having analytical solutions and published results. The effect of droplet number and arrangement on evaporation is studied by three cases with one (Case 1), two (Case 2) and four (Case 3) droplets impinging on hot wall in film boiling regime at a fixed temperature of wall and a constant non-dimensional distance between droplets. Droplet lift and spread, surface temperature, heat transfer, and evaporation rate are examined. It was observed that more liquid mass evaporated in Case 1 compared to the other cases. Droplet levitation begins early in Case 1 and very high levitation observed was partially due to contraction of its shape from elongated to a more circular form. Average surface temperature was also considerably reduced in Case 1 due to high droplet levitation.

Review of the Reported Measures of Clinical Validity and Clinical Utility as Arguments for the Implementation of Pharmacogenetic Testing: A Case Study of Statin-Induced Muscle Toxicity.

PubMed

Jansen, Marleen E; Rigter, T; Rodenburg, W; Fleur, T M C; Houwink, E J F; Weda, M; Cornel, Martina C

2017-01-01

Advances from pharmacogenetics (PGx) have not been implemented into health care to the expected extent. One gap that will be addressed in this study is a lack of reporting on clinical validity and clinical utility of PGx-tests. A systematic review of current reporting in scientific literature was conducted on publications addressing PGx in the context of statins and muscle toxicity. Eighty-nine publications were included and information was selected on reported measures of effect, arguments, and accompanying conclusions. Most authors report associations to quantify the relationship between a genetic variation an outcome, such as adverse drug responses. Conclusions on the implementation of a PGx-test are generally based on these associations, without explicit mention of other measures relevant to evaluate the test's clinical validity and clinical utility. To gain insight in the clinical impact and select useful tests, additional outcomes are needed to estimate the clinical validity and utility, such as cost-effectiveness.

Under-coding of secondary conditions in coded hospital health data: Impact of co-existing conditions, death status and number of codes in a record.

PubMed

Peng, Mingkai; Southern, Danielle A; Williamson, Tyler; Quan, Hude

2017-12-01

This study examined the coding validity of hypertension, diabetes, obesity and depression related to the presence of their co-existing conditions, death status and the number of diagnosis codes in hospital discharge abstract database. We randomly selected 4007 discharge abstract database records from four teaching hospitals in Alberta, Canada and reviewed their charts to extract 31 conditions listed in Charlson and Elixhauser comorbidity indices. Conditions associated with the four study conditions were identified through multivariable logistic regression. Coding validity (i.e. sensitivity, positive predictive value) of the four conditions was related to the presence of their associated conditions. Sensitivity increased with increasing number of diagnosis code. Impact of death on coding validity is minimal. Coding validity of conditions is closely related to its clinical importance and complexity of patients' case mix. We recommend mandatory coding of certain secondary diagnosis to meet the need of health research based on administrative health data.

Validation of an algorithm to identify children with biopsy-proven celiac disease from within health administrative data: An assessment of health services utilization patterns in Ontario, Canada

PubMed Central

Chan, Jason; Mack, David R.; Manuel, Douglas G.; Mojaverian, Nassim; de Nanassy, Joseph

2017-01-01

Importance Celiac disease (CD) is a common pediatric illness, and awareness of gluten-related disorders including CD is growing. Health administrative data represents a unique opportunity to conduct population-based surveillance of this chronic condition and assess the impact of caring for children with CD on the health system. Objective The objective of the study was to validate an algorithm based on health administrative data diagnostic codes to accurately identify children with biopsy-proven CD. We also evaluated trends over time in the use of health services related to CD by children in Ontario, Canada. Study design and setting We conducted a retrospective cohort study and validation study of population-based health administrative data in Ontario, Canada. All cases of biopsy-proven CD diagnosed 2005–2011 in Ottawa were identified through chart review from a large pediatric health care center, and linked to the Ontario health administrative data to serve as positive reference standard. All other children living within Ottawa served as the negative reference standard. Case-identifying algorithms based on outpatient physician visits with associated ICD-9 code for CD plus endoscopy billing code were constructed and tested. Sensitivity, specificity, PPV and NPV were tested for each algorithm (with 95% CI). Poisson regression, adjusting for sex and age at diagnosis, was used to explore the trend in outpatient visits associated with a CD diagnostic code from 1995–2011. Results The best algorithm to identify CD consisted of an endoscopy billing claim follow by 1 or more adult or pediatric gastroenterologist encounters after the endoscopic procedure. The sensitivity, specificity, PPV, and NPV for the algorithm were: 70.4% (95% CI 61.1–78.4%), >99.9% (95% CI >99.9->99.9%), 53.3% (95% CI 45.1–61.4%) and >99.9% (95% CI >99.9->99.9%) respectively. It identified 1289 suspected CD cases from Ontario-wide administrative data. There was a 9% annual increase in the use of this combination of CD-associated diagnostic codes in physician billing data (RR 1.09, 95% CI 1.07–1.10, P<0.001). Conclusions With its current structure and variables Ontario health administrative data is not suitable in identifying incident pediatric CD cases. The tested algorithms suffer from poor sensitivity and/or poor PPV, which increase the risk of case misclassification that could lead to biased estimation of CD incidence rate. This study reinforced the importance of validating the codes used to identify cohorts or outcomes when conducting research using health administrative data. PMID:28662204

Validation of Networks Derived from Snowball Sampling of Municipal Science Education Actors

ERIC Educational Resources Information Center

von der Fehr, Ane; Sølberg, Jan; Bruun, Jesper

2018-01-01

Social network analysis (SNA) has been used in many educational studies in the past decade, but what these studies have in common is that the populations in question in most cases are defined and known to the researchers studying the networks. Snowball sampling is an SNA methodology most often used to study hidden populations, for example, groups…

Optimal SVM parameter selection for non-separable and unbalanced datasets.

PubMed

Jiang, Peng; Missoum, Samy; Chen, Zhao

2014-10-01

This article presents a study of three validation metrics used for the selection of optimal parameters of a support vector machine (SVM) classifier in the case of non-separable and unbalanced datasets. This situation is often encountered when the data is obtained experimentally or clinically. The three metrics selected in this work are the area under the ROC curve (AUC), accuracy, and balanced accuracy. These validation metrics are tested using computational data only, which enables the creation of fully separable sets of data. This way, non-separable datasets, representative of a real-world problem, can be created by projection onto a lower dimensional sub-space. The knowledge of the separable dataset, unknown in real-world problems, provides a reference to compare the three validation metrics using a quantity referred to as the "weighted likelihood". As an application example, the study investigates a classification model for hip fracture prediction. The data is obtained from a parameterized finite element model of a femur. The performance of the various validation metrics is studied for several levels of separability, ratios of unbalance, and training set sizes.

Evaluation of the psychometric properties of the PROMIS Cancer Fatigue Short Form with cancer patients.

PubMed

Cessna, Julie M; Jim, Heather S L; Sutton, Steven K; Asvat, Yasmin; Small, Brent J; Salsman, John M; Zachariah, Babu; Fishman, Mayer; Field, Teresa; Fernandez, Hugo; Perez, Lia; Jacobsen, Paul B

2016-02-01

Fatigue is common among cancer patients and adversely impacts quality of life. As such, it is important to measure fatigue accurately in a way that is not burdensome to patients. The 7-item Patient Reported Outcome Measurement Information System (PROMIS) Cancer Fatigue Short Form scale was recently developed using item response theory (IRT). The current study evaluated the psychometric properties of this scale in two samples of cancer patients using classical test theory (CTT). Two samples were used: 121 men with prostate cancer and 136 patients scheduled to undergo hematopoietic cell transplantation (HCT) for hematologic cancer. All participants completed the PROMIS Cancer Fatigue Short Form as well as validated measures of fatigue, vitality, and depression. HCT patients also completed measures of anxiety, perceived stress, and a clinical interview designed to identify cases of cancer-related fatigue. PROMIS Cancer Fatigue Short Form items loaded on a single factor (CFI=0.948) and the scale demonstrated good internal consistency reliability in both samples (Cronbach's alphas>0.86). Correlations with psychosocial measures were significant (p values<.0001) and in the expected direction, offering evidence for convergent and concurrent validity. PROMIS Fatigue scores were significantly higher in patients who met case definition criteria for cancer-related fatigue (p<.0001), demonstrating criterion validity. The current study provides evidence that the PROMIS Cancer Fatigue Short Form is a reliable and valid measure of fatigue in cancer patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of the Psychometric Properties of the PROMIS Cancer Fatigue Short Form with Cancer Patients

PubMed Central

Cessna, Julie M.; Jim, Heather S.L.; Sutton, Steven K.; Asvat, Yasmin; Small, Brent J.; Salsman, John M.; Zachariah, Babu; Fishman, Mayer; Field, Teresa; Fernandez, Hugo; Perez, Lia; Jacobsen, Paul B.

2016-01-01

Objective Fatigue is common among cancer patients and adversely impacts quality of life. As such, it is important to measure fatigue accurately in a way that is not burdensome to patients. The 7-item Patient Reported Outcome Measurement Information System (PROMIS) Cancer Fatigue Short Form scale was recently developed using item response theory (IRT). The current study evaluated the psychometric properties of this scale in two samples of cancer patients using classical test theory (CTT). Methods Two samples were used: 121 men with prostate cancer and 136 patients scheduled to undergo hematopoietic cell transplantation (HCT) for hematologic cancer. All participants completed the PROMIS Cancer Fatigue Short Form as well as validated measures of fatigue, vitality, and depression. HCT patients also completed measures of anxiety, perceived stress, and a clinical interview designed to identify cases of cancer -related fatigue. Results PROMIS Cancer Fatigue Short Form items loaded on a single factor (CFI = 0.948) and the scale demonstrated good internal consistency reliability in both samples (Cronbach’s alphas > 0.86). Correlations with psychosocial measures were significant (p-values < .0001) and in the expected direction, offering evidence for convergent and concurrent validity. PROMIS Fatigue scores were significantly higher in patients who met case definition criteria for cancer-related fatigue (p < .0001), demonstrating criterion validity. Conclusion The current study provides evidence that the PROMIS Cancer Fatigue Short Form is a reliable and valid measure of fatigue in cancer patients. PMID:26800633

Reliability and Validity of Instruments for Assessing Perinatal Depression in African Settings: Systematic Review and Meta-Analysis

PubMed Central

Tsai, Alexander C.; Scott, Jennifer A.; Hung, Kristin J.; Zhu, Jennifer Q.; Matthews, Lynn T.; Psaros, Christina; Tomlinson, Mark

2013-01-01

Background A major barrier to improving perinatal mental health in Africa is the lack of locally validated tools for identifying probable cases of perinatal depression or for measuring changes in depression symptom severity. We systematically reviewed the evidence on the reliability and validity of instruments to assess perinatal depression in African settings. Methods and Findings Of 1,027 records identified through searching 7 electronic databases, we reviewed 126 full-text reports. We included 25 unique studies, which were disseminated in 26 journal articles and 1 doctoral dissertation. These enrolled 12,544 women living in nine different North and sub-Saharan African countries. Only three studies (12%) used instruments developed specifically for use in a given cultural setting. Most studies provided evidence of criterion-related validity (20 [80%]) or reliability (15 [60%]), while fewer studies provided evidence of construct validity, content validity, or internal structure. The Edinburgh postnatal depression scale (EPDS), assessed in 16 studies (64%), was the most frequently used instrument in our sample. Ten studies estimated the internal consistency of the EPDS (median estimated coefficient alpha, 0.84; interquartile range, 0.71-0.87). For the 14 studies that estimated sensitivity and specificity for the EPDS, we constructed 2 x 2 tables for each cut-off score. Using a bivariate random-effects model, we estimated a pooled sensitivity of 0.94 (95% confidence interval [CI], 0.68-0.99) and a pooled specificity of 0.77 (95% CI, 0.59-0.88) at a cut-off score of ≥9, with higher cut-off scores yielding greater specificity at the cost of lower sensitivity. Conclusions The EPDS can reliably and validly measure perinatal depression symptom severity or screen for probable postnatal depression in African countries, but more validation studies on other instruments are needed. In addition, more qualitative research is needed to adequately characterize local understandings of perinatal depression-like syndromes in different African contexts. PMID:24340036

Expectation-Based Efficiency and Quality Improvements in Research Administration: Multi-Institutional Case Studies

ERIC Educational Resources Information Center

Saha, Dhanonjoy C.; Ahmed, Abrar; Hanumandla, Shailaja

2011-01-01

Conventional wisdom may support the presumed notion that higher expectations increase efficiency and improve quality. However, this claim may only be validated when workers are equipped with appropriate tools, training, and a conducive work environment. This study implements various interventions, observes outcomes, and analyzes data collected in…

On-Line Representation of a Clinical Case and the Development of Expertise.

ERIC Educational Resources Information Center

Boshuizen, Henny P. A.; And Others

Designed to examine the structural differences in the representation of medical problems in subjects with varying degrees of medical expertise, this study uses an online, thinking-aloud technique to investigate the validity of Feltovich and Barrows' model of expert medical knowledge and illness scripts. Study methodology involved asking one…

Development of a cardiovascular risk score for use in low- and middle-income countries

USDA-ARS?s Scientific Manuscript database

Summary measures of cardiovascular risk have long been used in public health, but few include nutritional predictors despite extensive evidence linking diet and heart disease. Study objectives were to develop and validate a novel risk score in a case-control study of myocardial infarction (MI) condu...

Students' Perceptions of Their ICT-Based College English Course in China: A Case Study

ERIC Educational Resources Information Center

Zinan, Wen; Sai, George Teoh Boon

2017-01-01

This study investigated foreign language students' perceptions about their Information and Communication Technology (ICT)-based College English Course (CEC) in China. The research used a five-point Likert-scale questionnaire based on Simsek (2008). A factor analysis confirmed the construct validity of the questionnaire and 6 factors were…

Behavioral Monitoring of Sexual Offenders Against Children in Virtual Risk Situations: A Feasibility Study.

PubMed

Fromberger, Peter; Meyer, Sabrina; Jordan, Kirsten; Müller, Jürgen L

2018-01-01

The decision about unsupervised privileges for sexual offenders against children (SOC) is one of the most difficult decisions for practitioners in forensic high-security hospitals. Facing the possible consequences of the decision for the society, a valid and reliable risk management of SOCs is essential. Some risk management approaches provide frameworks for the construction of relevant future risk situations. Due to ethical reasons, it is not possible to evaluate the validity of constructed risk situations in reality. The aim of the study was to test if behavioral monitoring of SOCs in high-immersive virtual risk situations provides additional information for risk management. Six SOCs and seven non-offender controls (NOC) walked through three virtual risk situations, confronting the participant with a virtual child character. The participant had to choose between predefined answers representing approach or avoidance behavior. Frequency of chosen answers were analyzed in regards to knowledge of the participants about coping skills and coping skills focused during therapy. SOCs and NOCs behavior differed only in one risk scenario. Furthermore, SOCs showed in 89% of all cases a behavior not corresponding to their own belief about adequate behavior in comparable risk situations. In 62% of all cases, SOCs behaved not corresponding to coping skills they stated that therapists focused on during therapy. In 50% of all cases, SOCs behaved in correspondence to coping skills therapists stated that they focused on during therapy. Therapists predicted the behavior of SOCs in virtual risk situations incorrect in 25% of all cases. Thus, virtual risk scenarios provide the possibility for practitioners to monitor the behavior of SOCs and to test their decisions on unsupervised privileges without endangering the community. This may provide additional information for therapy progress. Further studies are necessary to evaluate the predictive and ecological validity of behavioral monitoring in virtual risk situations for real life situations.

Behavioral Monitoring of Sexual Offenders Against Children in Virtual Risk Situations: A Feasibility Study

PubMed Central

Fromberger, Peter; Meyer, Sabrina; Jordan, Kirsten; Müller, Jürgen L.

2018-01-01

The decision about unsupervised privileges for sexual offenders against children (SOC) is one of the most difficult decisions for practitioners in forensic high-security hospitals. Facing the possible consequences of the decision for the society, a valid and reliable risk management of SOCs is essential. Some risk management approaches provide frameworks for the construction of relevant future risk situations. Due to ethical reasons, it is not possible to evaluate the validity of constructed risk situations in reality. The aim of the study was to test if behavioral monitoring of SOCs in high-immersive virtual risk situations provides additional information for risk management. Six SOCs and seven non-offender controls (NOC) walked through three virtual risk situations, confronting the participant with a virtual child character. The participant had to choose between predefined answers representing approach or avoidance behavior. Frequency of chosen answers were analyzed in regards to knowledge of the participants about coping skills and coping skills focused during therapy. SOCs and NOCs behavior differed only in one risk scenario. Furthermore, SOCs showed in 89% of all cases a behavior not corresponding to their own belief about adequate behavior in comparable risk situations. In 62% of all cases, SOCs behaved not corresponding to coping skills they stated that therapists focused on during therapy. In 50% of all cases, SOCs behaved in correspondence to coping skills therapists stated that they focused on during therapy. Therapists predicted the behavior of SOCs in virtual risk situations incorrect in 25% of all cases. Thus, virtual risk scenarios provide the possibility for practitioners to monitor the behavior of SOCs and to test their decisions on unsupervised privileges without endangering the community. This may provide additional information for therapy progress. Further studies are necessary to evaluate the predictive and ecological validity of behavioral monitoring in virtual risk situations for real life situations. PMID:29559934

A validation study of a clinical prediction rule for screening asymptomatic chlamydia and gonorrhoea infections among heterosexuals in British Columbia.

PubMed

Falasinnu, Titilola; Gilbert, Mark; Gustafson, Paul; Shoveller, Jean

2016-02-01

One component of effective sexually transmitted infections (STIs) control is ensuring those at highest risk of STIs have access to clinical services because terminating transmission in this group will prevent most future cases. Here, we describe the results of a validation study of a clinical prediction rule for identifying individuals at increased risk for chlamydia and gonorrhoea infection derived in Vancouver, British Columbia (BC), against a population of asymptomatic patients attending sexual health clinics in other geographical settings in BC. We examined electronic records (2000-2012) from clinic visits at seven sexual health clinics in geographical locations outside Vancouver. The model's calibration and discrimination were examined by the area under the receiver operating characteristic curve (AUC) and the Hosmer-Lemeshow (H-L) statistic, respectively. We also examined the sensitivity and proportion of patients that would need to be screened at different cut-offs of the risk score. The prevalence of infection was 5.3% (n=10 425) in the geographical validation population. The prediction rule showed good performance in this population (AUC, 0.69; H-L p=0.26). Possible risk scores ranged from -2 to 27. We identified a risk score cut-off point of ≥8 that detected cases with a sensitivity of 86% by screening 63% of the geographical validation population. The prediction rule showed good generalisability in STI clinics outside of Vancouver with improved discriminative performance compared with temporal validation. The prediction rule has the potential for augmenting triaging services in STI clinics and enhancing targeted testing in population-based screening programmes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

‘‘Time after time’’: A Quali-T method for assessing music's impact on well-being

PubMed Central

2013-01-01

This article considers the question of how to produce ecologically valid assessments of music's role as a health technology. To address this question, I consider critically some of the standard quantitative instruments used to assess well-being and quality of life. I suggest that these instruments do not lend themselves well to the production of ecologically valid assessments and understandings for two reasons: (1) the process of data elicitation is removed from everyday meanings and practices and therefore risks producing data that is an artifact of the situation in which it is elicited (2) standard, quantitative instruments are not neutral but are rather discursive texts that are inevitably imbued with a politics of expertise and an image of the health care client. For these reasons, I suggest that we consider the question of how to develop ecologically valid, client-centered assessment measures. To that end, I introduce a third critique of the standard quantitative instruments, namely that they are associated with, and promote, an ontology of wellness/illness that downplays the temporally variable and situationally emergent nature of both wellness/illness and musical interventions themselves. As an alternative mode of assessment, I suggest that we reconsider the value of singular case studies and I describe a set of principles that can assist researchers to produce ecologically valid assessments. To this end I introduce the concept of the musical event as a more ecologically valid means for illuminating the specific mechanisms by which music aids well-being. I suggest that the case study approach is temporally sensitive, that it lends itself to an emergent ontology of wellness/illness, and that it is client-centered (and can also be user-led). PMID:23930990

Comparative assessment of three standardized robotic surgery training methods.

PubMed

Hung, Andrew J; Jayaratna, Isuru S; Teruya, Kara; Desai, Mihir M; Gill, Inderbir S; Goh, Alvin C

2013-10-01

To evaluate three standardized robotic surgery training methods, inanimate, virtual reality and in vivo, for their construct validity. To explore the concept of cross-method validity, where the relative performance of each method is compared. Robotic surgical skills were prospectively assessed in 49 participating surgeons who were classified as follows: 'novice/trainee': urology residents, previous experience <30 cases (n = 38) and 'experts': faculty surgeons, previous experience ≥30 cases (n = 11). Three standardized, validated training methods were used: (i) structured inanimate tasks; (ii) virtual reality exercises on the da Vinci Skills Simulator (Intuitive Surgical, Sunnyvale, CA, USA); and (iii) a standardized robotic surgical task in a live porcine model with performance graded by the Global Evaluative Assessment of Robotic Skills (GEARS) tool. A Kruskal-Wallis test was used to evaluate performance differences between novices and experts (construct validity). Spearman's correlation coefficient (ρ) was used to measure the association of performance across inanimate, simulation and in vivo methods (cross-method validity). Novice and expert surgeons had previously performed a median (range) of 0 (0-20) and 300 (30-2000) robotic cases, respectively (P < 0.001). Construct validity: experts consistently outperformed residents with all three methods (P < 0.001). Cross-method validity: overall performance of inanimate tasks significantly correlated with virtual reality robotic performance (ρ = -0.7, P < 0.001) and in vivo robotic performance based on GEARS (ρ = -0.8, P < 0.0001). Virtual reality performance and in vivo tissue performance were also found to be strongly correlated (ρ = 0.6, P < 0.001). We propose the novel concept of cross-method validity, which may provide a method of evaluating the relative value of various forms of skills education and assessment. We externally confirmed the construct validity of each featured training tool. © 2013 BJU International.

Construction and validation of forms: systematization of the care of people under hemodialysis.

PubMed

Arreguy-Sena, Cristina; Marques, Tais de Oliveira; Souza, Luciene Carnevale de; Alvarenga-Martins, Nathália; Krempser, Paula; Braga, Luciene Muniz; Parreira, Pedro Miguel Dos Santos Dinis

2018-01-01

create and validate forms to subsidize the systematization of nursing care with people on hemodialysis. institutional case study to support the systematization of assistance from the construction of forms for data collection, diagnoses, interventions and nursing results, using cross-mapping, Risner's reasoning, Neuman's theory, taxonomies of diagnoses, interventions and nursing results with application in clinical practice and validation by focal group with specialist nurses. 18 people on hemodialysis and 7 nurses participated. Consensus content of form matter with specialist nurses in the area (Crombach 0.86). The papers captured 43 diagnoses, 26 interventions and 78 nursing results depicting human responses in their singularities. the validated forms fill a gap by enabling the capture of human responses from people on hemodialysis and by subsidizing the planning of nursing care on a scientific basis.

Monitoring and validation of decentralised water and wastewater systems for increased uptake.

PubMed

Sharma, A K; Cook, S; Chong, M N

2013-01-01

Decentralised water and wastewater systems are being implemented to meet growing demand for municipal services either in combination with centralised systems or as standalone systems. In Australia, there has been increased investment in decentralised water and wastewater systems in response to the capacity constraints of existing centralised systems, an extended period of below average rainfall, uncertainly in traditional water sources due to potential climate change impacts, and the need to reduce the environmental impact of urban development. The implementation of decentralised water systems as a mainstream practice at different development scales is impeded by the knowledge gaps on their actual performance in a range of development types and settings. As the wide-spread uptake of these approaches in modern cities is relatively new compared to centralised approaches, there is limited information available on their planning, design, implementation, reliability and robustness. This paper presents a number of case studies where monitoring studies are under way to validate the performance of decentralised water and wastewater systems. The results from these case studies show the yield and reliability of these decentralised systems, as well as the associated energy demand and ecological footprint. The outputs from these case studies, and other monitoring studies, are important in improving decentralised system design guidelines and developing industry wide management norms for the operation and maintenance of decentralised systems.

Validating a benchmarking tool for audit of early outcomes after operations for head and neck cancer.

PubMed

Tighe, D; Sassoon, I; McGurk, M

2017-04-01

INTRODUCTION In 2013 all UK surgical specialties, with the exception of head and neck surgery, published outcome data adjusted for case mix for indicator operations. This paper reports a pilot study to validate a previously published risk adjustment score on patients from separate UK cancer centres. METHODS A case note audit was performed of 1,075 patients undergoing 1,218 operations for head and neck squamous cell carcinoma under general anaesthesia in 4 surgical centres. A logistic regression equation predicting for all complications, previously validated internally at sites A-C, was tested on a fourth external validation sample (site D, 172 operations) using receiver operating characteristic curves, Hosmer-Lemeshow goodness of fit analysis and Brier scores. RESULTS Thirty-day complication rates varied widely (34-51%) between the centres. The predictive score allowed imperfect risk adjustment (area under the curve: 0.70), with Hosmer-Lemeshow analysis suggesting good calibration. The Brier score changed from 0.19 for sites A-C to 0.23 when site D was also included, suggesting poor accuracy overall. CONCLUSIONS Marked differences in operative risk and patient case mix captured by the risk adjustment score do not explain all the differences in observed outcomes. Further investigation with different methods is recommended to improve modelling of risk. Morbidity is common, and usually has a major impact on patient recovery, ward occupancy, hospital finances and patient perception of quality of care. We hope comparative audit will highlight good performance and challenge underperformance where it exists.

Validation of classification algorithms for childhood diabetes identified from administrative data.

PubMed

Vanderloo, Saskia E; Johnson, Jeffrey A; Reimer, Kim; McCrea, Patrick; Nuernberger, Kimberly; Krueger, Hans; Aydede, Sema K; Collet, Jean-Paul; Amed, Shazhan

2012-05-01

Type 1 diabetes is the most common form of diabetes among children; however, the proportion of cases of childhood type 2 diabetes is increasing. In Canada, the National Diabetes Surveillance System (NDSS) uses administrative health data to describe trends in the epidemiology of diabetes, but does not specify diabetes type. The objective of this study was to validate algorithms to classify diabetes type in children <20 yr identified using the NDSS methodology. We applied the NDSS case definition to children living in British Columbia between 1 April 1996 and 31 March 2007. Through an iterative process, four potential classification algorithms were developed based on demographic characteristics and drug-utilization patterns. Each algorithm was then validated against a gold standard clinical database. Algorithms based primarily on an age rule (i.e., age <10 at diagnosis categorized type 1 diabetes) were most sensitive in the identification of type 1 diabetes; algorithms with restrictions on drug utilization (i.e., no prescriptions for insulin ± glucose monitoring strips categorized type 2 diabetes) were most sensitive for identifying type 2 diabetes. One algorithm was identified as having the optimal balance of sensitivity (Sn) and specificity (Sp) for the identification of both type 1 (Sn: 98.6%; Sp: 78.2%; PPV: 97.8%) and type 2 diabetes (Sn: 83.2%; Sp: 97.5%; PPV: 73.7%). Demographic characteristics in combination with drug-utilization patterns can be used to differentiate diabetes type among cases of pediatric diabetes identified within administrative health databases. Validation of similar algorithms in other regions is warranted. © 2011 John Wiley & Sons A/S.

Validating a benchmarking tool for audit of early outcomes after operations for head and neck cancer

PubMed Central

Sassoon, I; McGurk, M

2017-01-01

INTRODUCTION In 2013 all UK surgical specialties, with the exception of head and neck surgery, published outcome data adjusted for case mix for indicator operations. This paper reports a pilot study to validate a previously published risk adjustment score on patients from separate UK cancer centres. METHODS A case note audit was performed of 1,075 patients undergoing 1,218 operations for head and neck squamous cell carcinoma under general anaesthesia in 4 surgical centres. A logistic regression equation predicting for all complications, previously validated internally at sites A–C, was tested on a fourth external validation sample (site D, 172 operations) using receiver operating characteristic curves, Hosmer–Lemeshow goodness of fit analysis and Brier scores. RESULTS Thirty-day complication rates varied widely (34–51%) between the centres. The predictive score allowed imperfect risk adjustment (area under the curve: 0.70), with Hosmer–Lemeshow analysis suggesting good calibration. The Brier score changed from 0.19 for sites A–C to 0.23 when site D was also included, suggesting poor accuracy overall. CONCLUSIONS Marked differences in operative risk and patient case mix captured by the risk adjustment score do not explain all the differences in observed outcomes. Further investigation with different methods is recommended to improve modelling of risk. Morbidity is common, and usually has a major impact on patient recovery, ward occupancy, hospital finances and patient perception of quality of care. We hope comparative audit will highlight good performance and challenge underperformance where it exists. PMID:27917662

The impact of intra-operative interruptions on surgeons' perceived workload: an observational study in elective general and orthopedic surgery.

PubMed

Weigl, Matthias; Antoniadis, Sophia; Chiapponi, Costanza; Bruns, Christiane; Sevdalis, Nick

2015-01-01

Surgeons' intra-operative workload is critical for effective and safe surgical performance. Detrimental conditions in the operating room (OR) environment may add to perceived workload and jeopardize surgical performance and outcomes. This study aims to evaluate the impact of different intra-operative workflow interruptions on surgeons' capacity to manage their workload safely and efficiently. This was an observational study of intra-operative interruptions and self-rated workload in two surgical specialties (general, orthopedic/trauma surgery). Intra-operative interruptions were assessed via expert observation using a well-validated observation tool. Surgeons, nurses, and anesthesiologists assessed their intra-operative workload directly after case completion based on three items of the validated Surgery Task Load Index (mental demand, situational stress, distraction). A total of 56 elective cases (35 open, 21 laparoscopic) with 94 workload ratings were included. Mean intra-operative duration was 1 h 37 min. Intra-operative interruptions were on average observed 9.78 times per hour. People who entered/exited the OR (30.6 %) as well as telephone-/beeper-related disruptions (23.6 %) occurred most often. Equipment and OR environment-related interruptions were associated with highest interference with team functioning particularly in laparoscopic procedures. After identifying task and procedural influences, partial correlational analyses revealed that case-irrelevant communications were negatively associated with surgeons' mental fatigue and situational stress, whereas surgeons' reported distraction was increased by case-irrelevant communication and procedural disruptions. OR nurses' and anesthesiologists' perceived workload was also related to intra-operative interruption events. Our study documents the unique contribution of different interruptions on surgeons' workload; whereas case-irrelevant communications may be beneficial for mental fatigue and stress in routine cases, procedural interruptions and case-irrelevant communication may contribute to surgeons' mental focus deteriorating. Well-designed OR environments, surgical leadership, and awareness can help to control unnecessary interruptions for effective and safe surgical care.

Validation of a Syndromic Case Definition for Detecting Emergency Department Visits Potentially Related to Marijuana.

PubMed

DeYoung, Kathryn; Chen, Yushiuan; Beum, Robert; Askenazi, Michele; Zimmerman, Cali; Davidson, Arthur J

Reliable methods are needed to monitor the public health impact of changing laws and perceptions about marijuana. Structured and free-text emergency department (ED) visit data offer an opportunity to monitor the impact of these changes in near-real time. Our objectives were to (1) generate and validate a syndromic case definition for ED visits potentially related to marijuana and (2) describe a method for doing so that was less resource intensive than traditional methods. We developed a syndromic case definition for ED visits potentially related to marijuana, applied it to BioSense 2.0 data from 15 hospitals in the Denver, Colorado, metropolitan area for the period September through October 2015, and manually reviewed each case to determine true positives and false positives. We used the number of visits identified by and the positive predictive value (PPV) for each search term and field to refine the definition for the second round of validation on data from February through March 2016. Of 126 646 ED visits during the first period, terms in 524 ED visit records matched ≥1 search term in the initial case definition (PPV, 92.7%). Of 140 932 ED visits during the second period, terms in 698 ED visit records matched ≥1 search term in the revised case definition (PPV, 95.7%). After another revision, the final case definition contained 6 keywords for marijuana or derivatives and 5 diagnosis codes for cannabis use, abuse, dependence, poisoning, and lung disease. Our syndromic case definition and validation method for ED visits potentially related to marijuana could be used by other public health jurisdictions to monitor local trends and for other emerging concerns.

Development and validation of risk prediction equations to estimate future risk of blindness and lower limb amputation in patients with diabetes: cohort study

PubMed Central

Coupland, Carol

2015-01-01

Study question Is it possible to develop and externally validate risk prediction equations to estimate the 10 year risk of blindness and lower limb amputation in patients with diabetes aged 25-84 years? Methods This was a prospective cohort study using routinely collected data from general practices in England contributing to the QResearch and Clinical Practice Research Datalink (CPRD) databases during the study period 1998-2014. The equations were developed using 763 QResearch practices (n=454 575 patients with diabetes) and validated in 254 different QResearch practices (n=142 419) and 357 CPRD practices (n=206 050). Cox proportional hazards models were used to derive separate risk equations for blindness and amputation in men and women that could be evaluated at 10 years. Measures of calibration and discrimination were calculated in the two validation cohorts. Study answer and limitations Risk prediction equations to quantify absolute risk of blindness and amputation in men and women with diabetes have been developed and externally validated. In the QResearch derivation cohort, 4822 new cases of lower limb amputation and 8063 new cases of blindness occurred during follow-up. The risk equations were well calibrated in both validation cohorts. Discrimination was good in men in the external CPRD cohort for amputation (D statistic 1.69, Harrell’s C statistic 0.77) and blindness (D statistic 1.40, Harrell’s C statistic 0.73), with similar results in women and in the QResearch validation cohort. The algorithms are based on variables that patients are likely to know or that are routinely recorded in general practice computer systems. They can be used to identify patients at high risk for prevention or further assessment. Limitations include lack of formally adjudicated outcomes, information bias, and missing data. What this study adds Patients with type 1 or type 2 diabetes are at increased risk of blindness and amputation but generally do not have accurate assessments of the magnitude of their individual risks. The new algorithms calculate the absolute risk of developing these complications over a 10 year period in patients with diabetes, taking account of their individual risk factors. Funding, competing interests, data sharing JH-C is co-director of QResearch, a not for profit organisation which is a joint partnership between the University of Nottingham and Egton Medical Information Systems, and is also a paid director of ClinRisk Ltd. CC is a paid consultant statistician for ClinRisk Ltd. PMID:26560308

Assessing the validity of using serious game technology to analyze physician decision making.

PubMed

Mohan, Deepika; Angus, Derek C; Ricketts, Daniel; Farris, Coreen; Fischhoff, Baruch; Rosengart, Matthew R; Yealy, Donald M; Barnato, Amber E

2014-01-01

Physician non-compliance with clinical practice guidelines remains a critical barrier to high quality care. Serious games (using gaming technology for serious purposes) have emerged as a method of studying physician decision making. However, little is known about their validity. We created a serious game and evaluated its construct validity. We used the decision context of trauma triage in the Emergency Department of non-trauma centers, given widely accepted guidelines that recommend the transfer of severely injured patients to trauma centers. We designed cases with the premise that the representativeness heuristic influences triage (i.e. physicians make transfer decisions based on archetypes of severely injured patients rather than guidelines). We randomized a convenience sample of emergency medicine physicians to a control or cognitive load arm, and compared performance (disposition decisions, number of orders entered, time spent per case). We hypothesized that cognitive load would increase the use of heuristics, increasing the transfer of representative cases and decreasing the transfer of non-representative cases. We recruited 209 physicians, of whom 168 (79%) began and 142 (68%) completed the task. Physicians transferred 31% of severely injured patients during the game, consistent with rates of transfer for severely injured patients in practice. They entered the same average number of orders in both arms (control (C): 10.9 [SD 4.8] vs. cognitive load (CL):10.7 [SD 5.6], p = 0.74), despite spending less time per case in the control arm (C: 9.7 [SD 7.1] vs. CL: 11.7 [SD 6.7] minutes, p<0.01). Physicians were equally likely to transfer representative cases in the two arms (C: 45% vs. CL: 34%, p = 0.20), but were more likely to transfer non-representative cases in the control arm (C: 38% vs. CL: 26%, p = 0.03). We found that physicians made decisions consistent with actual practice, that we could manipulate cognitive load, and that load increased the use of heuristics, as predicted by cognitive theory.

The Electromagnetic Field for a PEC Wedge Over a Grounded Dielectric Slab: 1. Formulation and Validation

NASA Astrophysics Data System (ADS)

Daniele, Vito G.; Lombardi, Guido; Zich, Rodolfo S.

2017-12-01

Complex scattering problems are often made by composite structures where wedges and penetrable substrates may interact at near field. In this paper (Part 1) together with its companion paper (Part 2) we study the canonical problem constituted of a Perfectly Electrically Conducting (PEC) wedge lying on a grounded dielectric slab with a comprehensive mathematical model based on the application of the Generalized Wiener-Hopf Technique (GWHT) with the help of equivalent circuital representations for linear homogenous regions (angular and layered regions). The proposed procedure is valid for the general case, and the papers focus on E-polarization. The solution is obtained using analytical and semianalytical approaches that reduce the Wiener-Hopf factorization to integral equations. Several numerical test cases validate the proposed method. The scope of Part 1 is to present the method and its validation applied to the problem. The companion paper Part 2 focuses on the properties of the solution, and it presents physical and engineering insights as Geometrical Theory of Diffraction (GTD)/Uniform Theory of Diffraction(UTD) coefficients, total far fields, modal fields, and excitation of surface and leaky waves for different kinds of source. The structure is of interest in antenna technologies and electromagnetic compatibility (tip on a substrate with guiding and antenna properties).

The lack of selection bias in a snowball sampled case-control study on drug abuse.

PubMed

Lopes, C S; Rodrigues, L C; Sichieri, R

1996-12-01

Friend controls in matched case-control studies can be a potential source of bias based on the assumption that friends are more likely to share exposure factors. This study evaluates the role of selection bias in a case-control study that used the snowball sampling method based on friendship for the selection of cases and controls. The cases selected fro the study were drug abusers located in the community. Exposure was defined by the presence of at least one psychiatric diagnosis. Psychiatric and drug abuse/dependence diagnoses were made according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R) criteria. Cases and controls were matched on sex, age and friendship. The measurement of selection bias was made through the comparison of the proportion of exposed controls selected by exposed cases (p1) with the proportion of exposed controls selected by unexposed cases (p2). If p1 = p2 then, selection bias should not occur. The observed distribution of the 185 matched pairs having at least one psychiatric disorder showed a p1 value of 0.52 and a p2 value of 0.51, indicating no selection bias in this study. Our findings support the idea that the use of friend controls can produce a valid basis for a case-control study.

The validity of upper-limb neurodynamic tests for detecting peripheral neuropathic pain.

PubMed

Nee, Robert J; Jull, Gwendolen A; Vicenzino, Bill; Coppieters, Michel W

2012-05-01

The validity of upper-limb neurodynamic tests (ULNTs) for detecting peripheral neuropathic pain (PNP) was assessed by reviewing the evidence on plausibility, the definition of a positive test, reliability, and concurrent validity. Evidence was identified by a structured search for peer-reviewed articles published in English before May 2011. The quality of concurrent validity studies was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool, where appropriate. Biomechanical and experimental pain data support the plausibility of ULNTs. Evidence suggests that a positive ULNT should at least partially reproduce the patient's symptoms and that structural differentiation should change these symptoms. Data indicate that this definition of a positive ULNT is reliable when used clinically. Limited evidence suggests that the median nerve test, but not the radial nerve test, helps determine whether a patient has cervical radiculopathy. The median nerve test does not help diagnose carpal tunnel syndrome. These findings should be interpreted cautiously, because diagnostic accuracy might have been distorted by the investigators' definitions of a positive ULNT. Furthermore, patients with PNP who presented with increased nerve mechanosensitivity rather than conduction loss might have been incorrectly classified by electrophysiological reference standards as not having PNP. The only evidence for concurrent validity of the ulnar nerve test was a case study on cubital tunnel syndrome. We recommend that researchers develop more comprehensive reference standards for PNP to accurately assess the concurrent validity of ULNTs and continue investigating the predictive validity of ULNTs for prognosis or treatment response.

IMPROVING EMISSIONS ESTIMATES WITH COMPUTATIONAL INTELLIGENCE, DATABASE EXPANSION, AND COMPREHENSIVE VALIDATION

EPA Science Inventory

The report discusses an EPA investigation of techniques to improve methods for estimating volatile organic compound (VOC) emissions from area sources. Using the automobile refinishing industry for a detailed area source case study, an emission estimation method is being developed...

BurnCase 3D software validation study: Burn size measurement accuracy and inter-rater reliability.

PubMed

Parvizi, Daryousch; Giretzlehner, Michael; Wurzer, Paul; Klein, Limor Dinur; Shoham, Yaron; Bohanon, Fredrick J; Haller, Herbert L; Tuca, Alexandru; Branski, Ludwik K; Lumenta, David B; Herndon, David N; Kamolz, Lars-P

2016-03-01

The aim of this study was to compare the accuracy of burn size estimation using the computer-assisted software BurnCase 3D (RISC Software GmbH, Hagenberg, Austria) with that using a 2D scan, considered to be the actual burn size. Thirty artificial burn areas were pre planned and prepared on three mannequins (one child, one female, and one male). Five trained physicians (raters) were asked to assess the size of all wound areas using BurnCase 3D software. The results were then compared with the real wound areas, as determined by 2D planimetry imaging. To examine inter-rater reliability, we performed an intraclass correlation analysis with a 95% confidence interval. The mean wound area estimations of the five raters using BurnCase 3D were in total 20.7±0.9% for the child, 27.2±1.5% for the female and 16.5±0.1% for the male mannequin. Our analysis showed relative overestimations of 0.4%, 2.8% and 1.5% for the child, female and male mannequins respectively, compared to the 2D scan. The intraclass correlation between the single raters for mean percentage of the artificial burn areas was 98.6%. There was also a high intraclass correlation between the single raters and the 2D Scan visible. BurnCase 3D is a valid and reliable tool for the determination of total body surface area burned in standard models. Further clinical studies including different pediatric and overweight adult mannequins are warranted. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Application of validity theory and methodology to patient-reported outcome measures (PROMs): building an argument for validity.

PubMed

Hawkins, Melanie; Elsworth, Gerald R; Osborne, Richard H

2018-07-01

Data from subjective patient-reported outcome measures (PROMs) are now being used in the health sector to make or support decisions about individuals, groups and populations. Contemporary validity theorists define validity not as a statistical property of the test but as the extent to which empirical evidence supports the interpretation of test scores for an intended use. However, validity testing theory and methodology are rarely evident in the PROM validation literature. Application of this theory and methodology would provide structure for comprehensive validation planning to support improved PROM development and sound arguments for the validity of PROM score interpretation and use in each new context. This paper proposes the application of contemporary validity theory and methodology to PROM validity testing. The validity testing principles will be applied to a hypothetical case study with a focus on the interpretation and use of scores from a translated PROM that measures health literacy (the Health Literacy Questionnaire or HLQ). Although robust psychometric properties of a PROM are a pre-condition to its use, a PROM's validity lies in the sound argument that a network of empirical evidence supports the intended interpretation and use of PROM scores for decision making in a particular context. The health sector is yet to apply contemporary theory and methodology to PROM development and validation. The theoretical and methodological processes in this paper are offered as an advancement of the theory and practice of PROM validity testing in the health sector.

Diagnostic validity of early-onset obsessive-compulsive disorder in the Danish Psychiatric Central Register: findings from a cohort sample

PubMed Central

Powell, Shelagh; Koch, Susanne V; Crowley, James J; Matthiesen, Manuel; Grice, Dorothy E; Thomsen, Per H; Parner, E

2017-01-01

Objectives Employing national registers for research purposes depends on a high diagnostic validity. The aim of the present study was to examine the diagnostic validity of recorded diagnoses of early-onset obsessive-compulsive disorder (OCD) in the Danish Psychiatric Central Register (DPCR). Design Review of patient journals selected randomly through the DPCR. Method One hundred cases of OCD were randomly selected from DPCR. Using a predefined coding scheme based on the Children’s Yale Brown Obsessive Compulsive Scale (CYBOCS), experienced research nurse or child and adolescent psychiatrists assessed each journal to determine the presence/absence of OCD diagnostic criteria. The detailed assessments were reviewed by two senior child and adolescent psychiatrists to determine if diagnostic criteria were met. Primary outcome measurements Positive predictive value (PPV) was used as the primary outcome measurement. Results A total of 3462 children/adolescents received an OCD diagnosis as the main diagnosis between 1 January 1995 and 31 December 2015. The average age at diagnosis was 13.21±2.89 years. The most frequent registered OCD subcode was the combined diagnosis DF42.2. Of the 100 cases we examined, 35 had at least one registered comorbidity. For OCD, the PPV was good (PPV 0.85). Excluding journals with insufficient information, the PPV was 0.96. For the subcode F42.2 the PPV was 0.77. The inter-rater reliability was 0.94. The presence of the CYBOCS in the journal significantly increased the PPV for the OCD diagnosis altogether and for the subcode DF42.2. Conclusion The validity and reliability of International Classification of Disease 10th revision codes for OCD in the DPCR is generally high. The subcodes for predominant obsessions/predominant compulsions are less certain and should be used with caution. The results apply for both children and adolescents and for both older and more recent cases. Altogether, the study suggests that there is a high validity of the OCD diagnosis in the Danish National Registers. PMID:28928194

Validity of a family-centered approach for assessing infants' social-emotional wellbeing and their developmental context: a prospective cohort study.

PubMed

Hielkema, Margriet; De Winter, Andrea F; Reijneveld, Sijmen A

2017-06-15

Family-centered care seems promising in preventive pediatrics, but evidence is lacking as to whether this type of care is also valid as a means to identify risks to infants' social-emotional development. We aimed to examine the validity of such a family-centered approach. We conducted a prospective cohort study. During routine well-child visits (2-15 months), Preventive Child Healthcare (PCH) professionals used a family-centered approach, assessing domains as parents' competence, role of the partner, social support, barriers within the care-giving context, and child's wellbeing for 2976 children as protective, indistinct or a risk. If, based on the overall assessment (the families were labeled as "cases", N = 87), an intervention was considered necessary, parents filled in validated questionnaires covering the aforementioned domains. These questionnaires served as gold standards. For each case, two controls, matched by child-age and gender, also filled in questionnaires (N = 172). We compared PCH professionals' assessments with the parent-reported gold standards. Moreover, we evaluated which domain mostly contributed to the overall assessment. Spearman's rank correlation coefficients between PCH professionals' assessments and gold standards were overall reasonable (Spearman's rho 0.17-0.39) except for the domain barriers within the care-giving context. Scores on gold standards were significantly higher when PCH assessments were rated as "at risk" (overall and per domain).We found reasonable to excellent agreement regarding the absence of risk factors (negative agreement rate: 0.40-0.98), but lower agreement regarding the presence of risk factors (positive agreement rate: 0.00-0.67). An "at risk" assessment for the domain Barriers or life events within the care-giving context contributed most to being overall at risk, i.e. a case, odds ratio 100.1, 95%-confidence interval: 22.6 - infinity. Findings partially support the convergent validity of a family-centered approach in well-child care to assess infants' social-emotional wellbeing and their developmental context. Agreement was reasonable to excellent regarding protective factors, but lower regarding risk factors. Netherlands Trialregister, NTR2681. Date of registration: 05-01-2011, URL: http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2681 .

Testing expert systems

NASA Technical Reports Server (NTRS)

Chang, C. L.; Stachowitz, R. A.

1988-01-01

Software quality is of primary concern in all large-scale expert system development efforts. Building appropriate validation and test tools for ensuring software reliability of expert systems is therefore required. The Expert Systems Validation Associate (EVA) is a validation system under development at the Lockheed Artificial Intelligence Center. EVA provides a wide range of validation and test tools to check correctness, consistency, and completeness of an expert system. Testing a major function of EVA. It means executing an expert system with test cases with the intent of finding errors. In this paper, we describe many different types of testing such as function-based testing, structure-based testing, and data-based testing. We describe how appropriate test cases may be selected in order to perform good and thorough testing of an expert system.

Nursing diagnosis of grieving: content validity in perinatal loss situations.

PubMed

Paloma-Castro, Olga; Romero-Sánchez, José Manuel; Paramio-Cuevas, Juan Carlos; Pastor-Montero, Sonia María; Castro-Yuste, Cristina; Frandsen, Anna J; Albar-Marín, María Jesús; Bas-Sarmiento, Pilar; Moreno-Corral, Luis Javier

2014-06-01

To validate the content of the NANDA-I nursing diagnosis of grieving in situations of perinatal loss. Using the Fehring's model, 208 Spanish experts were asked to assess the adequacy of the defining characteristics and other manifestations identified in the literature for cases of perinatal loss. The content validity index was 0.867. Twelve of the 18 defining characteristics were validated, seven as major and five as minor. From the manifestations proposed, "empty inside" was considered as major. The nursing diagnosis of grieving fits in content to the cases of perinatal loss according to experts. The results have provided evidence to support the use of the diagnosis in care plans for said clinical situation. © 2013 NANDA International.

Application of Text Information Extraction System for Real-Time Cancer Case Identification in an Integrated Healthcare Organization.

PubMed

Xie, Fagen; Lee, Janet; Munoz-Plaza, Corrine E; Hahn, Erin E; Chen, Wansu

2017-01-01

Surgical pathology reports (SPR) contain rich clinical diagnosis information. The text information extraction system (TIES) is an end-to-end application leveraging natural language processing technologies and focused on the processing of pathology and/or radiology reports. We deployed the TIES system and integrated SPRs into the TIES system on a daily basis at Kaiser Permanente Southern California. The breast cancer cases diagnosed in December 2013 from the Cancer Registry (CANREG) were used to validate the performance of the TIES system. The National Cancer Institute Metathesaurus (NCIM) concept terms and codes to describe breast cancer were identified through the Unified Medical Language System Terminology Service (UTS) application. The identified NCIM codes were used to search for the coded SPRs in the back-end datastore directly. The identified cases were then compared with the breast cancer patients pulled from CANREG. A total of 437 breast cancer concept terms and 14 combinations of "breast"and "cancer" terms were identified from the UTS application. A total of 249 breast cancer cases diagnosed in December 2013 was pulled from CANREG. Out of these 249 cases, 241 were successfully identified by the TIES system from a total of 457 reports. The TIES system also identified an additional 277 cases that were not part of the validation sample. Out of the 277 cases, 11% were determined as highly likely to be cases after manual examinations, and 86% were in CANREG but were diagnosed in months other than December of 2013. The study demonstrated that the TIES system can effectively identify potential breast cancer cases in our care setting. Identified potential cases can be easily confirmed by reviewing the corresponding annotated reports through the front-end visualization interface. The TIES system is a great tool for identifying potential various cancer cases in a timely manner and on a regular basis in support of clinical research studies.

Response rates in case-control studies of cancer by era of fieldwork and by characteristics of study design.

PubMed

Xu, Mengting; Richardson, Lesley; Campbell, Sally; Pintos, Javier; Siemiatycki, Jack

2018-04-09

The purpose of this study was to describe time trends in response rates in case-control studies of cancer and identify study design factors that influence response rate. We reviewed 370 case-control studies of cancer published in 12 journals during indicator years in each of the last four decades. We estimated time trends of response rates and reasons for nonresponse in each of the following types of study subjects: cases, medical source controls, and population controls. We also estimated response rates according to characteristics of study context. Median response rates among cases and population controls were between 75% and 80% in the 1970s. Between 1971 and 2010, study response rates declined by 0.31% per year for cases and 0.78% for population controls. Only a minority of studies reported reasons for nonparticipation; subject refusal was the most common reported reason. Studies conducted in North America had lower median response rates than studies conducted in Europe. In-person and telephone interviews elicited higher response rates than mail questionnaires. Response rates from case-control studies of cancer have declined, and this could threaten the validity of results derived from these studies. Copyright © 2018 Elsevier Inc. All rights reserved.

Validation of a patient-level medication regimen complexity index as a possible tool to identify patients for medication therapy management intervention.

PubMed

Hirsch, Jan D; Metz, Kelli R; Hosokawa, Patrick W; Libby, Anne M

2014-08-01

The Medication Regimen Complexity Index (MRCI) is a 65-item instrument that can be used to quantify medication regimen complexity at the patient level, capturing all prescribed and over-the-counter medications. Although the MRCI has been used in several studies, the narrow scope of the initial validation limits application at a population or clinical practice level. To conduct a MRCI validation pertinent to the desired clinical use to identify patients for medication therapy management interventions. An expert panel of clinical pharmacists ranked medication regimen complexity for two samples of cases: a single-disease cohort (diabetes mellitus) and a multiple-disease cohort (diabetes mellitus, hypertension, human immunodeficiency virus infection, geriatric depression). Cases for expert panel review were selected from 400 ambulatory clinic patients, and each case description included data that were available via claims or electronic medical records (EMRs). Construct validity was assessed using patient-level MRCI scores, medication count, and additional patient data. Concordance was evaluated using weighted κ agreement statistic, and correlations were determined using Spearman rank-order correlation coefficient (ρ) or Kendall τ. Moderate to good concordance between patient-level MRCI scores and expert medication regimen complexity ranking was observed (claims data, consensus ranking: single-disease cohort 0.55, multiple disease cohort 0.63). In contrast, only fair to moderate concordance was observed for medication count (single-disease cohort 0.33, multiple-disease cohort 0.48). Adding more-detailed administration directions from EMR data did not improve concordance. MRCI convergent validity was supported by strong correlations with medication count (all cohorts 0.90) and moderate correlations with morbidity measures (e.g., all cohorts; number of comorbidities 0.46, Chronic Disease Score 0.46). Nonsignificant correlation of MRCI scores with age and gender (all cohorts 0.08 and 0.06, respectively) supported MRCI divergent validity. This study used cross-sectional, retrospective patient data for a small number of patients and clinical pharmacists from only two universities; therefore, results may have limited generalizability. The patient-level MRCI is a valid tool for assessing medication regimen complexity that can be applied by using data commonly found in claims and EMR databases and could be useful to identify patients who may benefit from medication therapy management. © 2014 The Authors Pharmacotherapy published by Wiley Periodicals, Inc. on behalf of Pharmacotherapy Publications, Inc.

Scientific Inquiry Competency Perception Scale (The Case of Kazak Post-Graduate Students) Reliability and Validity Study

ERIC Educational Resources Information Center

Gelisli, Yücel; Beisenbayeva, Lyazzat

2017-01-01

The purpose of the current study is to develop a reliable scale to be used to determine the scientific inquiry competency perception of post-graduate students engaged in post-graduate studies in the field of educational sciences and teacher education in Kazakhstan. The study employed the descriptive method. Within the context of the study, a scale…

[An instrument for assessing clinical aptitude in cervicovaginitis in the family medicine practice].

PubMed

Arrieta-Pérez, Raúl Tomás; Lona-Calixto, Beatriz

2011-01-01

the cervicovaginitis is one of the first twelve causes on demand at primary care medicine thus the family physician must be able to identify and treat it. The objective was to validate a constructed instrument for measuring the clinical aptitude on cervicovaginitis. cross-sectional, descriptive, prolective study was carried out. An instrument with five clinical cases was done. It has seven indicators, whose answers were true, false and I do not know. The validity content was done by three family physicians and a Gynecologist, with experience in education. The trustworthiness was determined by means of the test of Kuder-Richardson formula 20 with the results obtained in a pilot test in 50 family medicine residents. the instrument was constituted by five clinical cases with 140 Items distributed in seven indicators with 20 items for each indicator and a total of 70 true answers and 70 false answers; seven categories for the degree of clinical aptitude settled down. The trustworthiness of the instrument was 0.81. the instrument is valid and reliable to identify the clinical aptitude of the family physician on cervicovaginitis.

Predictive Model for Particle Residence Time Distributions in Riser Reactors. Part 1: Model Development and Validation

DOE PAGES

Foust, Thomas D.; Ziegler, Jack L.; Pannala, Sreekanth; ...

2017-02-28

Here in this computational study, we model the mixing of biomass pyrolysis vapor with solid catalyst in circulating riser reactors with a focus on the determination of solid catalyst residence time distributions (RTDs). A comprehensive set of 2D and 3D simulations were conducted for a pilot-scale riser using the Eulerian-Eulerian two-fluid modeling framework with and without sub-grid-scale models for the gas-solids interaction. A validation test case was also simulated and compared to experiments, showing agreement in the pressure gradient and RTD mean and spread. For simulation cases, it was found that for accurate RTD prediction, the Johnson and Jackson partialmore » slip solids boundary condition was required for all models and a sub-grid model is useful so that ultra high resolutions grids that are very computationally intensive are not required. Finally, we discovered a 2/3 scaling relation for the RTD mean and spread when comparing resolved 2D simulations to validated unresolved 3D sub-grid-scale model simulations.« less

Laboratory compliance with the American Society of Clinical Oncology/College of American Pathologists human epidermal growth factor receptor 2 testing guidelines: a 3-year comparison of validation procedures.

PubMed

Dyhdalo, Kathryn S; Fitzgibbons, Patrick L; Goldsmith, Jeffery D; Souers, Rhona J; Nakhleh, Raouf E

2014-07-01

The American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) published guidelines in 2007 regarding testing accuracy, interpretation, and reporting of results for HER2 studies. A 2008 survey identified areas needing improved compliance. To reassess laboratory response to those guidelines following a full accreditation cycle for an updated snapshot of laboratory practices regarding ASCO/CAP guidelines. In 2011, a survey was distributed with the HER2 immunohistochemistry (IHC) proficiency testing program identical to the 2008 survey. Of the 1150 surveys sent, 977 (85.0%) were returned, comparable to the original survey response in 2008 (757 of 907; 83.5%). New participants submitted 124 of 977 (12.7%) surveys. The median laboratory accession rate was 14,788 cases with 211 HER2 tests performed annually. Testing was validated with fluorescence in situ hybridization in 49.1% (443 of 902) of the laboratories; 26.3% (224 of 853) of the laboratories used another IHC assay. The median number of cases to validate fluorescence in situ hybridization (n = 40) and IHC (n = 27) was similar to those in 2008. Ninety-five percent concordance with fluorescence in situ hybridization was achieved by 76.5% (254 of 332) of laboratories for IHC(-) findings and 70.4% (233 of 331) for IHC(+) cases. Ninety-five percent concordance with another IHC assay was achieved by 71.1% (118 of 168) of the laboratories for negative findings and 69.6% (112 of 161) of the laboratories for positive cases. The proportion of laboratories interpreting HER2 IHC using ASCO/CAP guidelines (86.6% [798 of 921] in 2011; 83.8% [605 of 722] in 2008) remains similar. Although fixation time improvements have been made, assay validation deficiencies still exist. The results of this survey were shared within the CAP, including the Laboratory Accreditation Program and the ASCO/CAP panel revising the HER2 guidelines published in October 2013. The Laboratory Accreditation Program checklist was changed to strengthen HER2 validation practices.