Kumar, Y Kiran; Mehta, Shashi Bhushan; Ramachandra, Manjunath
2017-01-01
The purpose of this work is to provide some validation methods for evaluating the hemodynamic assessment of Cerebral Arteriovenous Malformation (CAVM). This article emphasizes the importance of validating noninvasive measurements for CAVM patients, which are designed using lumped models for complex vessel structure. The validation of the hemodynamics assessment is based on invasive clinical measurements and cross-validation techniques with the Philips proprietary validated software's Qflow and 2D Perfursion. The modeling results are validated for 30 CAVM patients for 150 vessel locations. Mean flow, diameter, and pressure were compared between modeling results and with clinical/cross validation measurements, using an independent two-tailed Student t test. Exponential regression analysis was used to assess the relationship between blood flow, vessel diameter, and pressure between them. Univariate analysis is used to assess the relationship between vessel diameter, vessel cross-sectional area, AVM volume, AVM pressure, and AVM flow results were performed with linear or exponential regression. Modeling results were compared with clinical measurements from vessel locations of cerebral regions. Also, the model is cross validated with Philips proprietary validated software's Qflow and 2D Perfursion. Our results shows that modeling results and clinical results are nearly matching with a small deviation. In this article, we have validated our modeling results with clinical measurements. The new approach for cross-validation is proposed by demonstrating the accuracy of our results with a validated product in a clinical environment.
Double Cross-Validation in Multiple Regression: A Method of Estimating the Stability of Results.
ERIC Educational Resources Information Center
Rowell, R. Kevin
In multiple regression analysis, where resulting predictive equation effectiveness is subject to shrinkage, it is especially important to evaluate result replicability. Double cross-validation is an empirical method by which an estimate of invariance or stability can be obtained from research data. A procedure for double cross-validation is…
Cross-validation pitfalls when selecting and assessing regression and classification models.
Krstajic, Damjan; Buturovic, Ljubomir J; Leahy, David E; Thomas, Simon
2014-03-29
We address the problem of selecting and assessing classification and regression models using cross-validation. Current state-of-the-art methods can yield models with high variance, rendering them unsuitable for a number of practical applications including QSAR. In this paper we describe and evaluate best practices which improve reliability and increase confidence in selected models. A key operational component of the proposed methods is cloud computing which enables routine use of previously infeasible approaches. We describe in detail an algorithm for repeated grid-search V-fold cross-validation for parameter tuning in classification and regression, and we define a repeated nested cross-validation algorithm for model assessment. As regards variable selection and parameter tuning we define two algorithms (repeated grid-search cross-validation and double cross-validation), and provide arguments for using the repeated grid-search in the general case. We show results of our algorithms on seven QSAR datasets. The variation of the prediction performance, which is the result of choosing different splits of the dataset in V-fold cross-validation, needs to be taken into account when selecting and assessing classification and regression models. We demonstrate the importance of repeating cross-validation when selecting an optimal model, as well as the importance of repeating nested cross-validation when assessing a prediction error.
Cross-Validation of easyCBM Reading Cut Scores in Washington: 2009-2010. Technical Report #1109
ERIC Educational Resources Information Center
Irvin, P. Shawn; Park, Bitnara Jasmine; Anderson, Daniel; Alonzo, Julie; Tindal, Gerald
2011-01-01
This technical report presents results from a cross-validation study designed to identify optimal cut scores when using easyCBM[R] reading tests in Washington state. The cross-validation study analyzes data from the 2009-2010 academic year for easyCBM[R] reading measures. A sample of approximately 900 students per grade, randomly split into two…
Cross-Validation of the Africentrism Scale.
ERIC Educational Resources Information Center
Kwate, Naa Oyo A.
2003-01-01
Cross-validated the Africentrism Scale, investigating the relationship between Africentrism and demographic variables in a diverse sample of individuals of African descent. Results indicated that the scale demonstrated solid internal consistency and convergent validity. Age and education related to Africentrism, with younger and less educated…
Cross-Validation of easyCBM Reading Cut Scores in Oregon: 2009-2010. Technical Report #1108
ERIC Educational Resources Information Center
Park, Bitnara Jasmine; Irvin, P. Shawn; Anderson, Daniel; Alonzo, Julie; Tindal, Gerald
2011-01-01
This technical report presents results from a cross-validation study designed to identify optimal cut scores when using easyCBM[R] reading tests in Oregon. The cross-validation study analyzes data from the 2009-2010 academic year for easyCBM[R] reading measures. A sample of approximately 2,000 students per grade, randomly split into two groups of…
An empirical assessment of validation practices for molecular classifiers
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
Korjus, Kristjan; Hebart, Martin N.; Vicente, Raul
2016-01-01
Supervised machine learning methods typically require splitting data into multiple chunks for training, validating, and finally testing classifiers. For finding the best parameters of a classifier, training and validation are usually carried out with cross-validation. This is followed by application of the classifier with optimized parameters to a separate test set for estimating the classifier’s generalization performance. With limited data, this separation of test data creates a difficult trade-off between having more statistical power in estimating generalization performance versus choosing better parameters and fitting a better model. We propose a novel approach that we term “Cross-validation and cross-testing” improving this trade-off by re-using test data without biasing classifier performance. The novel approach is validated using simulated data and electrophysiological recordings in humans and rodents. The results demonstrate that the approach has a higher probability of discovering significant results than the standard approach of cross-validation and testing, while maintaining the nominal alpha level. In contrast to nested cross-validation, which is maximally efficient in re-using data, the proposed approach additionally maintains the interpretability of individual parameters. Taken together, we suggest an addition to currently used machine learning approaches which may be particularly useful in cases where model weights do not require interpretation, but parameters do. PMID:27564393
Korjus, Kristjan; Hebart, Martin N; Vicente, Raul
2016-01-01
Supervised machine learning methods typically require splitting data into multiple chunks for training, validating, and finally testing classifiers. For finding the best parameters of a classifier, training and validation are usually carried out with cross-validation. This is followed by application of the classifier with optimized parameters to a separate test set for estimating the classifier's generalization performance. With limited data, this separation of test data creates a difficult trade-off between having more statistical power in estimating generalization performance versus choosing better parameters and fitting a better model. We propose a novel approach that we term "Cross-validation and cross-testing" improving this trade-off by re-using test data without biasing classifier performance. The novel approach is validated using simulated data and electrophysiological recordings in humans and rodents. The results demonstrate that the approach has a higher probability of discovering significant results than the standard approach of cross-validation and testing, while maintaining the nominal alpha level. In contrast to nested cross-validation, which is maximally efficient in re-using data, the proposed approach additionally maintains the interpretability of individual parameters. Taken together, we suggest an addition to currently used machine learning approaches which may be particularly useful in cases where model weights do not require interpretation, but parameters do.
LeDell, Erin; Petersen, Maya; van der Laan, Mark
In binary classification problems, the area under the ROC curve (AUC) is commonly used to evaluate the performance of a prediction model. Often, it is combined with cross-validation in order to assess how the results will generalize to an independent data set. In order to evaluate the quality of an estimate for cross-validated AUC, we obtain an estimate of its variance. For massive data sets, the process of generating a single performance estimate can be computationally expensive. Additionally, when using a complex prediction method, the process of cross-validating a predictive model on even a relatively small data set can still require a large amount of computation time. Thus, in many practical settings, the bootstrap is a computationally intractable approach to variance estimation. As an alternative to the bootstrap, we demonstrate a computationally efficient influence curve based approach to obtaining a variance estimate for cross-validated AUC.
Petersen, Maya; van der Laan, Mark
2015-01-01
In binary classification problems, the area under the ROC curve (AUC) is commonly used to evaluate the performance of a prediction model. Often, it is combined with cross-validation in order to assess how the results will generalize to an independent data set. In order to evaluate the quality of an estimate for cross-validated AUC, we obtain an estimate of its variance. For massive data sets, the process of generating a single performance estimate can be computationally expensive. Additionally, when using a complex prediction method, the process of cross-validating a predictive model on even a relatively small data set can still require a large amount of computation time. Thus, in many practical settings, the bootstrap is a computationally intractable approach to variance estimation. As an alternative to the bootstrap, we demonstrate a computationally efficient influence curve based approach to obtaining a variance estimate for cross-validated AUC. PMID:26279737
A cross-validation package driving Netica with python
Fienen, Michael N.; Plant, Nathaniel G.
2014-01-01
Bayesian networks (BNs) are powerful tools for probabilistically simulating natural systems and emulating process models. Cross validation is a technique to avoid overfitting resulting from overly complex BNs. Overfitting reduces predictive skill. Cross-validation for BNs is known but rarely implemented due partly to a lack of software tools designed to work with available BN packages. CVNetica is open-source, written in Python, and extends the Netica software package to perform cross-validation and read, rebuild, and learn BNs from data. Insights gained from cross-validation and implications on prediction versus description are illustrated with: a data-driven oceanographic application; and a model-emulation application. These examples show that overfitting occurs when BNs become more complex than allowed by supporting data and overfitting incurs computational costs as well as causing a reduction in prediction skill. CVNetica evaluates overfitting using several complexity metrics (we used level of discretization) and its impact on performance metrics (we used skill).
Piette, Elizabeth R; Moore, Jason H
2018-01-01
Machine learning methods and conventions are increasingly employed for the analysis of large, complex biomedical data sets, including genome-wide association studies (GWAS). Reproducibility of machine learning analyses of GWAS can be hampered by biological and statistical factors, particularly so for the investigation of non-additive genetic interactions. Application of traditional cross validation to a GWAS data set may result in poor consistency between the training and testing data set splits due to an imbalance of the interaction genotypes relative to the data as a whole. We propose a new cross validation method, proportional instance cross validation (PICV), that preserves the original distribution of an independent variable when splitting the data set into training and testing partitions. We apply PICV to simulated GWAS data with epistatic interactions of varying minor allele frequencies and prevalences and compare performance to that of a traditional cross validation procedure in which individuals are randomly allocated to training and testing partitions. Sensitivity and positive predictive value are significantly improved across all tested scenarios for PICV compared to traditional cross validation. We also apply PICV to GWAS data from a study of primary open-angle glaucoma to investigate a previously-reported interaction, which fails to significantly replicate; PICV however improves the consistency of testing and training results. Application of traditional machine learning procedures to biomedical data may require modifications to better suit intrinsic characteristics of the data, such as the potential for highly imbalanced genotype distributions in the case of epistasis detection. The reproducibility of genetic interaction findings can be improved by considering this variable imbalance in cross validation implementation, such as with PICV. This approach may be extended to problems in other domains in which imbalanced variable distributions are a concern.
Cross-Validation of Survival Bump Hunting by Recursive Peeling Methods.
Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J Sunil
2014-08-01
We introduce a survival/risk bump hunting framework to build a bump hunting model with a possibly censored time-to-event type of response and to validate model estimates. First, we describe the use of adequate survival peeling criteria to build a survival/risk bump hunting model based on recursive peeling methods. Our method called "Patient Recursive Survival Peeling" is a rule-induction method that makes use of specific peeling criteria such as hazard ratio or log-rank statistics. Second, to validate our model estimates and improve survival prediction accuracy, we describe a resampling-based validation technique specifically designed for the joint task of decision rule making by recursive peeling (i.e. decision-box) and survival estimation. This alternative technique, called "combined" cross-validation is done by combining test samples over the cross-validation loops, a design allowing for bump hunting by recursive peeling in a survival setting. We provide empirical results showing the importance of cross-validation and replication.
Cross-Validation of Survival Bump Hunting by Recursive Peeling Methods
Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J. Sunil
2015-01-01
We introduce a survival/risk bump hunting framework to build a bump hunting model with a possibly censored time-to-event type of response and to validate model estimates. First, we describe the use of adequate survival peeling criteria to build a survival/risk bump hunting model based on recursive peeling methods. Our method called “Patient Recursive Survival Peeling” is a rule-induction method that makes use of specific peeling criteria such as hazard ratio or log-rank statistics. Second, to validate our model estimates and improve survival prediction accuracy, we describe a resampling-based validation technique specifically designed for the joint task of decision rule making by recursive peeling (i.e. decision-box) and survival estimation. This alternative technique, called “combined” cross-validation is done by combining test samples over the cross-validation loops, a design allowing for bump hunting by recursive peeling in a survival setting. We provide empirical results showing the importance of cross-validation and replication. PMID:26997922
Zhang, Yin-Ping; Wei, Huan-Huan; Wang, Wen; Xia, Ru-Yi; Zhou, Xiao-Ling; Porr, Caroline; Lammi, Mikko
2016-04-01
The Osteoporosis Assessment Questionnaire Short Version (OPAQ-SV) was cross-culturally adapted to measure health-related quality of life in Chinese osteoporotic fracture females and then validated in China for its psychometric properties. Cross-cultural adaptation, including translation of the original OPAQ-SV into Mandarin Chinese language, was performed according to published guidelines. Validation of the newly cross-culturally adapted OPAQ-SV was conducted by sampling 234 Chinese osteoporotic fracture females and also a control group of 235 Chinese osteoporotic females without fractures, producing robust content, construct, and discriminant validation results. Major categories of reliability were also met: the Cronbach alpha coefficient was 0.975, indicating good internal consistency; the test-retest reliability was 0.80; and principal component analysis resulted in a 6-factor structure explaining 75.847 % of the total variance. Further, the Comparative Fit Index result was 0.922 following the modified model confirmatory factor analysis, and the chi-squared test was 1.98. The root mean squared error of approximation was 0.078. Moreover, significant differences were revealed between females with fractures and those without fractures across all domains (p < 0.001). Overall, the newly cross-culturally adapted OPAQ-SV appears to possess adequate validity and reliability and may be utilized in clinical trials to assess the health-related quality of life in Chinese osteoporotic fracture females.
Cross-validation to select Bayesian hierarchical models in phylogenetics.
Duchêne, Sebastián; Duchêne, David A; Di Giallonardo, Francesca; Eden, John-Sebastian; Geoghegan, Jemma L; Holt, Kathryn E; Ho, Simon Y W; Holmes, Edward C
2016-05-26
Recent developments in Bayesian phylogenetic models have increased the range of inferences that can be drawn from molecular sequence data. Accordingly, model selection has become an important component of phylogenetic analysis. Methods of model selection generally consider the likelihood of the data under the model in question. In the context of Bayesian phylogenetics, the most common approach involves estimating the marginal likelihood, which is typically done by integrating the likelihood across model parameters, weighted by the prior. Although this method is accurate, it is sensitive to the presence of improper priors. We explored an alternative approach based on cross-validation that is widely used in evolutionary analysis. This involves comparing models according to their predictive performance. We analysed simulated data and a range of viral and bacterial data sets using a cross-validation approach to compare a variety of molecular clock and demographic models. Our results show that cross-validation can be effective in distinguishing between strict- and relaxed-clock models and in identifying demographic models that allow growth in population size over time. In most of our empirical data analyses, the model selected using cross-validation was able to match that selected using marginal-likelihood estimation. The accuracy of cross-validation appears to improve with longer sequence data, particularly when distinguishing between relaxed-clock models. Cross-validation is a useful method for Bayesian phylogenetic model selection. This method can be readily implemented even when considering complex models where selecting an appropriate prior for all parameters may be difficult.
Vanderploeg, Rodney D; Cooper, Douglas B; Belanger, Heather G; Donnell, Alison J; Kennedy, Jan E; Hopewell, Clifford A; Scott, Steven G
2014-01-01
To develop and cross-validate internal validity scales for the Neurobehavioral Symptom Inventory (NSI). Four existing data sets were used: (1) outpatient clinical traumatic brain injury (TBI)/neurorehabilitation database from a military site (n = 403), (2) National Department of Veterans Affairs TBI evaluation database (n = 48 175), (3) Florida National Guard nonclinical TBI survey database (n = 3098), and (4) a cross-validation outpatient clinical TBI/neurorehabilitation database combined across 2 military medical centers (n = 206). Secondary analysis of existing cohort data to develop (study 1) and cross-validate (study 2) internal validity scales for the NSI. The NSI, Mild Brain Injury Atypical Symptoms, and Personality Assessment Inventory scores. Study 1: Three NSI validity scales were developed, composed of 5 unusual items (Negative Impression Management [NIM5]), 6 low-frequency items (LOW6), and the combination of 10 nonoverlapping items (Validity-10). Cut scores maximizing sensitivity and specificity on these measures were determined, using a Mild Brain Injury Atypical Symptoms score of 8 or more as the criterion for invalidity. Study 2: The same validity scale cut scores again resulted in the highest classification accuracy and optimal balance between sensitivity and specificity in the cross-validation sample, using a Personality Assessment Inventory Negative Impression Management scale with a T score of 75 or higher as the criterion for invalidity. The NSI is widely used in the Department of Defense and Veterans Affairs as a symptom-severity assessment following TBI, but is subject to symptom overreporting or exaggeration. This study developed embedded NSI validity scales to facilitate the detection of invalid response styles. The NSI Validity-10 scale appears to hold considerable promise for validity assessment when the NSI is used as a population-screening tool.
Lam, Simon C
2014-05-01
To perform detailed psychometric testing of the compliance with standard precautions scale (CSPS) in measuring compliance with standard precautions of clinical nurses and to conduct cross-cultural pilot testing and assess the relevance of the CSPS on an international platform. A cross-sectional and correlational design with repeated measures. Nursing students from a local registered nurse training university, nurses from different hospitals in Hong Kong, and experts in an international conference. The psychometric properties of the CSPS were evaluated via internal consistency, 2-week and 3-month test-retest reliability, concurrent validation, and construct validation. The cross-cultural pilot testing and relevance check was examined by experts on infection control from various developed and developing regions. Among 453 participants, 193 were nursing students, 165 were enrolled nurses, and 95 were registered nurses. The results showed that the CSPS had satisfactory reliability (Cronbach α = 0.73; intraclass correlation coefficient, 0.79 for 2-week test-retest and 0.74 for 3-month test-retest) and validity (optimum correlation with criterion measure; r = 0.76, P < .001; satisfactory results on known-group method and hypothesis testing). A total of 19 experts from 16 countries assured that most of the CSPS findings were relevant and globally applicable. The CSPS demonstrated satisfactory results on the basis of the standard international criteria on psychometric testing, which ascertained the reliability and validity of this instrument in measuring the compliance of clinical nurses with standard precautions. The cross-cultural pilot testing further reinforced the instrument's relevance and applicability in most developed and developing regions.
Sisic, Nedim; Jelicic, Mario; Pehar, Miran; Spasic, Miodrag; Sekulic, Damir
2016-01-01
In basketball, anthropometric status is an important factor when identifying and selecting talents, while agility is one of the most vital motor performances. The aim of this investigation was to evaluate the influence of anthropometric variables and power capacities on different preplanned agility performances. The participants were 92 high-level, junior-age basketball players (16-17 years of age; 187.6±8.72 cm in body height, 78.40±12.26 kg in body mass), randomly divided into a validation and cross-validation subsample. The predictors set consisted of 16 anthropometric variables, three tests of power-capacities (Sargent-jump, broad-jump and medicine-ball-throw) as predictors. The criteria were three tests of agility: a T-Shape-Test; a Zig-Zag-Test, and a test of running with a 180-degree turn (T180). Forward stepwise multiple regressions were calculated for validation subsamples and then cross-validated. Cross validation included correlations between observed and predicted scores, dependent samples t-test between predicted and observed scores; and Bland Altman graphics. Analysis of the variance identified centres being advanced in most of the anthropometric indices, and medicine-ball-throw (all at P<0.05); with no significant between-position-differences for other studied motor performances. Multiple regression models originally calculated for the validation subsample were then cross-validated, and confirmed for Zig-zag-Test (R of 0.71 and 0.72 for the validation and cross-validation subsample, respectively). Anthropometrics were not strongly related to agility performance, but leg length is found to be negatively associated with performance in basketball-specific agility. Power capacities are confirmed to be an important factor in agility. The results highlighted the importance of sport-specific tests when studying pre-planned agility performance in basketball. The improvement in power capacities will probably result in an improvement in agility in basketball athletes, while anthropometric indices should be used in order to identify those athletes who can achieve superior agility performance.
Guidelines To Validate Control of Cross-Contamination during Washing of Fresh-Cut Leafy Vegetables.
Gombas, D; Luo, Y; Brennan, J; Shergill, G; Petran, R; Walsh, R; Hau, H; Khurana, K; Zomorodi, B; Rosen, J; Varley, R; Deng, K
2017-02-01
The U.S. Food and Drug Administration requires food processors to implement and validate processes that will result in significantly minimizing or preventing the occurrence of hazards that are reasonably foreseeable in food production. During production of fresh-cut leafy vegetables, microbial contamination that may be present on the product can spread throughout the production batch when the product is washed, thus increasing the risk of illnesses. The use of antimicrobials in the wash water is a critical step in preventing such water-mediated cross-contamination; however, many factors can affect antimicrobial efficacy in the production of fresh-cut leafy vegetables, and the procedures for validating this key preventive control have not been articulated. Producers may consider three options for validating antimicrobial washing as a preventive control for cross-contamination. Option 1 involves the use of a surrogate for the microbial hazard and the demonstration that cross-contamination is prevented by the antimicrobial wash. Option 2 involves the use of antimicrobial sensors and the demonstration that a critical antimicrobial level is maintained during worst-case operating conditions. Option 3 validates the placement of the sensors in the processing equipment with the demonstration that a critical antimicrobial level is maintained at all locations, regardless of operating conditions. These validation options developed for fresh-cut leafy vegetables may serve as examples for validating processes that prevent cross-contamination during washing of other fresh produce commodities.
Accelerating cross-validation with total variation and its application to super-resolution imaging
NASA Astrophysics Data System (ADS)
Obuchi, Tomoyuki; Ikeda, Shiro; Akiyama, Kazunori; Kabashima, Yoshiyuki
2017-12-01
We develop an approximation formula for the cross-validation error (CVE) of a sparse linear regression penalized by ℓ_1-norm and total variation terms, which is based on a perturbative expansion utilizing the largeness of both the data dimensionality and the model. The developed formula allows us to reduce the necessary computational cost of the CVE evaluation significantly. The practicality of the formula is tested through application to simulated black-hole image reconstruction on the event-horizon scale with super resolution. The results demonstrate that our approximation reproduces the CVE values obtained via literally conducted cross-validation with reasonably good precision.
Comprehensive Assessment of Emotional Disturbance: A Cross-Validation Approach
ERIC Educational Resources Information Center
Fisher, Emily S.; Doyon, Katie E.; Saldana, Enrique; Allen, Megan Redding
2007-01-01
Assessing a student for emotional disturbance is a serious and complex task given the stigma of the label and the ambiguities of the federal definition. One way that school psychologists can be more confident in their assessment results is to cross validate data from different sources using the RIOT approach (Review, Interview, Observe, Test).…
Methodology and issues of integral experiments selection for nuclear data validation
NASA Astrophysics Data System (ADS)
Tatiana, Ivanova; Ivanov, Evgeny; Hill, Ian
2017-09-01
Nuclear data validation involves a large suite of Integral Experiments (IEs) for criticality, reactor physics and dosimetry applications. [1] Often benchmarks are taken from international Handbooks. [2, 3] Depending on the application, IEs have different degrees of usefulness in validation, and usually the use of a single benchmark is not advised; indeed, it may lead to erroneous interpretation and results. [1] This work aims at quantifying the importance of benchmarks used in application dependent cross section validation. The approach is based on well-known General Linear Least Squared Method (GLLSM) extended to establish biases and uncertainties for given cross sections (within a given energy interval). The statistical treatment results in a vector of weighting factors for the integral benchmarks. These factors characterize the value added by a benchmark for nuclear data validation for the given application. The methodology is illustrated by one example, selecting benchmarks for 239Pu cross section validation. The studies were performed in the framework of Subgroup 39 (Methods and approaches to provide feedback from nuclear and covariance data adjustment for improvement of nuclear data files) established at the Working Party on International Nuclear Data Evaluation Cooperation (WPEC) of the Nuclear Science Committee under the Nuclear Energy Agency (NEA/OECD).
Lohrer, Heinz; Nauck, Tanja
2009-01-01
Background Achilles tendinopathy is the predominant overuse injury in runners. To further investigate this overload injury in transverse and longitudinal studies a valid, responsive and reliable outcome measure is demanded. Most questionnaires have been developed for English-speaking populations. This is also true for the VISA-A score, so far representing the only valid, reliable, and disease specific questionnaire for Achilles tendinopathy. To internationally compare research results, to perform multinational studies or to exclude bias originating from subpopulations speaking different languages within one country an equivalent instrument is demanded in different languages. The aim of this study was therefore to cross-cultural adapt and validate the VISA-A questionnaire for German-speaking Achilles tendinopathy patients. Methods According to the "guidelines for the process of cross-cultural adaptation of self-report measures" the VISA-A score was cross-culturally adapted into German (VISA-A-G) using six steps: Translation, synthesis, back translation, expert committee review, pretesting (n = 77), and appraisal of the adaptation process by an advisory committee determining the adequacy of the cross-cultural adaptation. The resulting VISA-A-G was then subjected to an analysis of reliability, validity, and internal consistency in 30 Achilles tendinopathy patients and 79 asymptomatic people. Concurrent validity was tested against a generic tendon grading system (Percy and Conochie) and against a classification system for the effect of pain on athletic performance (Curwin and Stanish). Results The "advisory committee" determined the VISA-A-G questionnaire as been translated "acceptable". The VISA-A-G questionnaire showed moderate to excellent test-retest reliability (ICC = 0.60 to 0.97). Concurrent validity showed good coherence when correlated with the grading system of Curwin and Stanish (rho = -0.95) and for the Percy and Conochie grade of severity (rho 0.95). Internal consistency (Cronbach's alpha) for the total VISA-A-G scores of the patients was calculated to be 0.737. Conclusion The VISA-A questionnaire was successfully cross-cultural adapted and validated for use in German speaking populations. The psychometric properties of the VISA-A-G questionnaire are similar to those of the original English version. It therefore can be recommended as a sufficiently robust tool for future measuring clinical severity of Achilles tendinopathy in German speaking patients. PMID:19878572
Validity of Hansen-Roach cross sections in low-enriched uranium systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Busch, R.D.; O'Dell, R.D.
Within the nuclear criticality safety community, the Hansen-Roach 16 group cross section set has been the standard'' for use in k{sub eff} calculations over the past 30 years. Yet even with its widespread acceptance, there are still questions about its validity and adequacy, about the proper procedure for calculating the potential scattering cross section, {sigma}{sub p}, for uranium and plutonium, and about the concept of resonance self shielding and its impact on cross sections. This paper attempts to address these questions. It provides a brief background on the Hansen-Roach cross sections. Next is presented a review of resonances in crossmore » sections, self shielding of these resonances, and the use of {sigma}{sub p} to characterize resonance self shielding. Three prescriptions for calculating {sigma}{sub p} are given. Finally, results of several calculations of k{sub eff} on low-enriched uranium systems are provided to confirm the validity of the Hansen-Roach cross sections when applied to such systems.« less
A New Symptom Model for Autism Cross-Validated in an Independent Sample
ERIC Educational Resources Information Center
Boomsma, A.; Van Lang, N. D. J.; De Jonge, M. V.; De Bildt, A. A.; Van Engeland, H.; Minderaa, R. B.
2008-01-01
Background: Results from several studies indicated that a symptom model other than the DSM triad might better describe symptom domains of autism. The present study focused on a) investigating the stability of a new symptom model for autism by cross-validating it in an independent sample and b) examining the invariance of the model regarding three…
Zometa, Carlos S; Dedrick, Robert; Knox, Michael D; Westhoff, Wayne; Siri, Rodrigo Simán; Debaldo, Ann
2007-06-01
An instrument developed in the United States by the Centers for Disease Control and Prevention to assess HIV/AIDS knowledge and four attitudinal dimensions (Peer Pressure, Abstinence, Drug Use, and Threat of HIV Infection) and an instrument developed by Basen-Engquist et al. (1999) to measure abstinence and condom use were translated, cross-culturally adapted, and validated for use with Spanish-speaking high school students in El Salvador. A back-translation of the English version was cross-culturally adapted using two different review panels and pilot-tested with Salvadorian students. An expert panel established content validity, and confirmatory factor analysis provided support for construct validity. Results indicated that the methodology was successful in cross-culturally adapting the instrument developed by the Centers for Disease Control and Prevention and the instrument developed by Basen-Engquist et al. The psychometric properties of the knowledge section were acceptable and there was partial support for the four-factor attitudinal model underlying the CDC instrument and the two-factor model underlying the Basen-Engquist et al. instrument. Additional studies with Spanish-speaking populations (either in the United States or Latin America) are needed to evaluate the generalizability of the present results.
NASA Astrophysics Data System (ADS)
Mundava, C.; Helmholz, P.; Schut, A. G. T.; Corner, R.; McAtee, B.; Lamb, D. W.
2014-09-01
The objective of this paper is to test the relationships between Above Ground Biomass (AGB) and remotely sensed vegetation indices for AGB assessments in the Kimberley area in Western Australia. For 19 different sites, vegetation indices were derived from eight Landsat ETM+ scenes over a period of two years (2011-2013). The sites were divided into three groups (Open plains, Bunch grasses and Spinifex) based on similarities in dominant vegetation types. Dry and green biomass fractions were measured at these sites. Single and multiple regression relationships between vegetation indices and green and total AGB were calibrated and validated using a "leave site out" cross validation. Four tests were compared: (1) relationships between AGB and vegetation indices combining all sites; (2) separate relationships per site group; (3) multiple regressions including selected vegetation indices per site group; and (4) as in 3 but including rainfall and elevation data. Results indicate that relationships based on single vegetation indices are moderately accurate for green biomass in wide open plains covered with annual grasses. The cross-validation results for green AGB improved for a combination of indices for the Open plains and Bunch grasses sites, but not for Spinifex sites. When rainfall and elevation data are included, cross validation improved slightly with a Q2 of 0.49-0.72 for Open plains and Bunch grasses sites respectively. Cross validation results for total AGB were moderately accurate (Q2 of 0.41) for Open plains but weak or absent for other site groups despite good calibration results, indicating strong influence of site-specific factors.
NASA Astrophysics Data System (ADS)
Kitterød, Nils-Otto
2017-08-01
Unconsolidated sediment cover thickness (D) above bedrock was estimated by using a publicly available well database from Norway, GRANADA. General challenges associated with such databases typically involve clustering and bias. However, if information about the horizontal distance to the nearest bedrock outcrop (L) is included, does the spatial estimation of D improve? This idea was tested by comparing two cross-validation results: ordinary kriging (OK) where L was disregarded; and co-kriging (CK) where cross-covariance between D and L was included. The analysis showed only minor differences between OK and CK with respect to differences between estimation and true values. However, the CK results gave in general less estimation variance compared to the OK results. All observations were declustered and transformed to standard normal probability density functions before estimation and back-transformed for the cross-validation analysis. The semivariogram analysis gave correlation lengths for D and L of approx. 10 and 6 km. These correlations reduce the estimation variance in the cross-validation analysis because more than 50 % of the data material had two or more observations within a radius of 5 km. The small-scale variance of D, however, was about 50 % of the total variance, which gave an accuracy of less than 60 % for most of the cross-validation cases. Despite the noisy character of the observations, the analysis demonstrated that L can be used as secondary information to reduce the estimation variance of D.
Maters, Gemma A.; Sanderman, Robbert; Kim, Aimee Y.; Coyne, James C.
2013-01-01
Objective The Hospital Anxiety and Depression Scale (HADS) is widely used to screen for anxiety and depression. A large literature is citable in support of its validity, but difficulties are increasingly being identified, such as inexplicably discrepant optimal cutpoints and inconsistent factor-structures. This article examines whether these problems could be due to the construction of the HADS that poses difficulties for translation and cross-cultural use. Methods Authors’ awareness of difficulties translating the HADS were identified by examining 20% of studies using the HADS, obtained by a systematic literature search in Pubmed and PsycINFO in May 2012. Reports of use of translations and validation studies were recorded for papers from non-English speaking countries. Narrative and systematic reviews were examined for how authors dealt with different translations. Results Of 417 papers from non-English speaking countries, only 45% indicated whether a translation was used. Studies validating translations were cited in 54%. Seventeen reviews, incorporating data from diverse translated versions, were examined. Only seven mentioned issues of language and culture, and none indicated insurmountable problems in integrating results from different translations. Conclusion Initial decisions concerning item content and response options likely leave the HADS difficult to translate, but we failed to find an acknowledgment of problems in articles involving its translation and cross-cultural use. Investigators’ lack of awareness of these issues can lead to anomalous results and difficulties in interpretation and integration of these results. Reviews tend to overlook these issues and most reviews indiscriminately integrate results from studies performed in different countries. Cross-culturally valid, but literally translated versions of the HADS may not be attainable, and specific cutpoints may not be valid across cultures and language. Claims about rates of anxiety and depression based on integrating cross-cultural data or using the same cutpoint across languages and culture should be subject to critical scrutiny. PMID:23976969
PCA as a practical indicator of OPLS-DA model reliability.
Worley, Bradley; Powers, Robert
Principal Component Analysis (PCA) and Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) are powerful statistical modeling tools that provide insights into separations between experimental groups based on high-dimensional spectral measurements from NMR, MS or other analytical instrumentation. However, when used without validation, these tools may lead investigators to statistically unreliable conclusions. This danger is especially real for Partial Least Squares (PLS) and OPLS, which aggressively force separations between experimental groups. As a result, OPLS-DA is often used as an alternative method when PCA fails to expose group separation, but this practice is highly dangerous. Without rigorous validation, OPLS-DA can easily yield statistically unreliable group separation. A Monte Carlo analysis of PCA group separations and OPLS-DA cross-validation metrics was performed on NMR datasets with statistically significant separations in scores-space. A linearly increasing amount of Gaussian noise was added to each data matrix followed by the construction and validation of PCA and OPLS-DA models. With increasing added noise, the PCA scores-space distance between groups rapidly decreased and the OPLS-DA cross-validation statistics simultaneously deteriorated. A decrease in correlation between the estimated loadings (added noise) and the true (original) loadings was also observed. While the validity of the OPLS-DA model diminished with increasing added noise, the group separation in scores-space remained basically unaffected. Supported by the results of Monte Carlo analyses of PCA group separations and OPLS-DA cross-validation metrics, we provide practical guidelines and cross-validatory recommendations for reliable inference from PCA and OPLS-DA models.
Photodetachment cross sections of negative ions - The range of validity of the Wigner threshold law
NASA Technical Reports Server (NTRS)
Farley, John W.
1989-01-01
The threshold behavior of the photodetachment cross section of negative ions as a function of photon frequency is usually described by the Wigner law. This paper reports the results of a model calculation using the zero-core-contribution (ZCC) approximation. Theoretical expressions for the leading correction to the Wigner law are developed, giving the range of validity of the Wigner law and the expected accuracy. The results are relevant to extraction of electron affinities from experimental photodetachment data.
The Cross-Cultural Loss Scale: development and psychometric evaluation.
Wang, Kenneth T; Wei, Meifen; Zhao, Ran; Chuang, Chih-Chun; Li, Feihan
2015-03-01
The Cross-Cultural Loss Scale (CCLS), a measure of loss associated with crossing national boundaries, was developed across 2 samples of international students. With Sample 1 (N = 262), exploratory factor analyses were used to select the 14 CCLS items and to determine 3 factors: Belonging-Competency (α = .87), National Privileges (α = .68), and Access to Home Familiarity (α = .72). With Sample 2, confirmatory factor analyses (N = 256) cross-validated the 3-factor oblique model as well as a bifactor model. Cronbach alphas of CCLS subscale scores in Sample 2 ranged from .73 to .87. The validity of the CCLS scores was supported by its associations with related variables in the expected directions. Perceived cross-cultural losses were positively associated with negative affect, migration grief and loss, and discrimination and were negatively associated with life satisfaction, positive affect, general self-efficacy, and social connection with mainstream society. Moreover, the CCLS total and 2 subscale scores added significant incremental variance in predicting subjective well-being over and above related constructs. The results indicated measurement invariance and validity equivalency for the CCLS scores between men and women. The overall results from these 2 samples support CCLS as a psychometrically strong measure. 2015 APA, all rights reserved
Maters, Gemma A; Sanderman, Robbert; Kim, Aimee Y; Coyne, James C
2013-01-01
The Hospital Anxiety and Depression Scale (HADS) is widely used to screen for anxiety and depression. A large literature is citable in support of its validity, but difficulties are increasingly being identified, such as inexplicably discrepant optimal cutpoints and inconsistent factor-structures. This article examines whether these problems could be due to the construction of the HADS that poses difficulties for translation and cross-cultural use. Authors' awareness of difficulties translating the HADS were identified by examining 20% of studies using the HADS, obtained by a systematic literature search in Pubmed and PsycINFO in May 2012. Reports of use of translations and validation studies were recorded for papers from non-English speaking countries. Narrative and systematic reviews were examined for how authors dealt with different translations. Of 417 papers from non-English speaking countries, only 45% indicated whether a translation was used. Studies validating translations were cited in 54%. Seventeen reviews, incorporating data from diverse translated versions, were examined. Only seven mentioned issues of language and culture, and none indicated insurmountable problems in integrating results from different translations. Initial decisions concerning item content and response options likely leave the HADS difficult to translate, but we failed to find an acknowledgment of problems in articles involving its translation and cross-cultural use. Investigators' lack of awareness of these issues can lead to anomalous results and difficulties in interpretation and integration of these results. Reviews tend to overlook these issues and most reviews indiscriminately integrate results from studies performed in different countries. Cross-culturally valid, but literally translated versions of the HADS may not be attainable, and specific cutpoints may not be valid across cultures and language. Claims about rates of anxiety and depression based on integrating cross-cultural data or using the same cutpoint across languages and culture should be subject to critical scrutiny.
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.
Glassmire, David M; Toofanian Ross, Parnian; Kinney, Dominique I; Nitch, Stephen R
2016-06-01
Two studies were conducted to identify and cross-validate cutoff scores on the Wechsler Adult Intelligence Scale-Fourth Edition Digit Span-based embedded performance validity (PV) measures for individuals with schizophrenia spectrum disorders. In Study 1, normative scores were identified on Digit Span-embedded PV measures among a sample of patients (n = 84) with schizophrenia spectrum diagnoses who had no known incentive to perform poorly and who put forth valid effort on external PV tests. Previously identified cutoff scores resulted in unacceptable false positive rates and lower cutoff scores were adopted to maintain specificity levels ≥90%. In Study 2, the revised cutoff scores were cross-validated within a sample of schizophrenia spectrum patients (n = 96) committed as incompetent to stand trial. Performance on Digit Span PV measures was significantly related to Full Scale IQ in both studies, indicating the need to consider the intellectual functioning of examinees with psychotic spectrum disorders when interpreting scores on Digit Span PV measures. © The Author(s) 2015.
ERIC Educational Resources Information Center
Anderson, Daniel; Alonzo, Julie; Tindal, Gerald
2011-01-01
In this technical report, we document the results of a cross-validation study designed to identify optimal cut-scores for the use of the easyCBM[R] mathematics test in the state of Washington. A large sample, randomly split into two groups of roughly equal size, was used for this study. Students' performance classification on the Washington state…
A Cross-Validation of easyCBM[R] Mathematics Cut Scores in Oregon: 2009-2010. Technical Report #1104
ERIC Educational Resources Information Center
Anderson, Daniel; Alonzo, Julie; Tindal, Gerald
2011-01-01
In this technical report, we document the results of a cross-validation study designed to identify optimal cut-scores for the use of the easyCBM[R] mathematics test in Oregon. A large sample, randomly split into two groups of roughly equal size, was used for this study. Students' performance classification on the Oregon state test was used as the…
Cross-cultural adaptation of instruments assessing breastfeeding determinants: a multi-step approach
2014-01-01
Background Cross-cultural adaptation is a necessary process to effectively use existing instruments in other cultural and language settings. The process of cross-culturally adapting, including translation, of existing instruments is considered a critical set to establishing a meaningful instrument for use in another setting. Using a multi-step approach is considered best practice in achieving cultural and semantic equivalence of the adapted version. We aimed to ensure the content validity of our instruments in the cultural context of KwaZulu-Natal, South Africa. Methods The Iowa Infant Feeding Attitudes Scale, Breastfeeding Self-Efficacy Scale-Short Form and additional items comprise our consolidated instrument, which was cross-culturally adapted utilizing a multi-step approach during August 2012. Cross-cultural adaptation was achieved through steps to maintain content validity and attain semantic equivalence in the target version. Specifically, Lynn’s recommendation to apply an item-level content validity index score was followed. The revised instrument was translated and back-translated. To ensure semantic equivalence, Brislin’s back-translation approach was utilized followed by the committee review to address any discrepancies that emerged from translation. Results Our consolidated instrument was adapted to be culturally relevant and translated to yield more reliable and valid results for use in our larger research study to measure infant feeding determinants effectively in our target cultural context. Conclusions Undertaking rigorous steps to effectively ensure cross-cultural adaptation increases our confidence that the conclusions we make based on our self-report instrument(s) will be stronger. In this way, our aim to achieve strong cross-cultural adaptation of our consolidated instruments was achieved while also providing a clear framework for other researchers choosing to utilize existing instruments for work in other cultural, geographic and population settings. PMID:25285151
Ko, Young-Mi; Park, Won-Beom; Lim, Jae-Young
2010-03-15
Validation of a translated, culturally adapted questionnaire. We developed a Korean version of the Chronic Pain Coping Inventory-42 (CPCI-42) by performing a cross-cultural adaptation, and evaluated its reliability and validity. The CPCI is widely used and validated instruments for measuring coping strategies in chronic pain. However, no validated and culturally adapted version was available in Asian countries. We assessed 142 patients with chronic low back pain using the CPCI-42 and measures of physical disability, pain, and quality of life. Results for 93 of the 142 patients exhibited test-retest reliability. The interval time of collecting retest data varied from 2 weeks to 1 month. Criterion validity was evaluated using correlations between the CPCI-42 and the Oswestry Disability Index, the Brief Pain Inventory, and the Short Form 36-item Health Survey (version 2.0). Construct validity was computed using exploratory factor analysis. The Korean version of the CPCI-42 had a high internal consistency (Cronbach's alpha >0.70) with the exception of results for task persistence and relaxation. Illness-focused coping (guarding, resting, asking for assistance) and other-focused coping (seeking social support) were most significantly correlated with Oswestry Disability Index, Brief Pain Inventory, and Short Form 36-item Health Survey, respectively. Outcomes for task persistence were contrary to other subscales in wellness-focused coping. Construct validity by factor analysis produced similar results to the original CPCI subscale. However, several factors showed cross-loading in 8 factor solutions. Despite linguistic and cultural differences, the Korean version of the CPCI-42 is overall a meaningful tool, and produces results sufficiently similar to the original CPCI-42.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Xiaolin; Ye, Li; Wang, Xiaoxiang
2012-12-15
Several recent reports suggested that hydroxylated polybrominated diphenyl ethers (HO-PBDEs) may disturb thyroid hormone homeostasis. To illuminate the structural features for thyroid hormone activity of HO-PBDEs and the binding mode between HO-PBDEs and thyroid hormone receptor (TR), the hormone activity of a series of HO-PBDEs to thyroid receptors β was studied based on the combination of 3D-QSAR, molecular docking, and molecular dynamics (MD) methods. The ligand- and receptor-based 3D-QSAR models were obtained using Comparative Molecular Similarity Index Analysis (CoMSIA) method. The optimum CoMSIA model with region focusing yielded satisfactory statistical results: leave-one-out cross-validation correlation coefficient (q{sup 2}) was 0.571 andmore » non-cross-validation correlation coefficient (r{sup 2}) was 0.951. Furthermore, the results of internal validation such as bootstrapping, leave-many-out cross-validation, and progressive scrambling as well as external validation indicated the rationality and good predictive ability of the best model. In addition, molecular docking elucidated the conformations of compounds and key amino acid residues at the docking pocket, MD simulation further determined the binding process and validated the rationality of docking results. -- Highlights: ► The thyroid hormone activities of HO-PBDEs were studied by 3D-QSAR. ► The binding modes between HO-PBDEs and TRβ were explored. ► 3D-QSAR, molecular docking, and molecular dynamics (MD) methods were performed.« less
Pat, Lucio; Ali, Bassam; Guerrero, Armando; Córdova, Atl V.; Garduza, José P.
2016-01-01
Attenuated total reflectance-Fourier transform infrared spectrometry and chemometrics model was used for determination of physicochemical properties (pH, redox potential, free acidity, electrical conductivity, moisture, total soluble solids (TSS), ash, and HMF) in honey samples. The reference values of 189 honey samples of different botanical origin were determined using Association Official Analytical Chemists, (AOAC), 1990; Codex Alimentarius, 2001, International Honey Commission, 2002, methods. Multivariate calibration models were built using partial least squares (PLS) for the measurands studied. The developed models were validated using cross-validation and external validation; several statistical parameters were obtained to determine the robustness of the calibration models: (PCs) optimum number of components principal, (SECV) standard error of cross-validation, (R 2 cal) coefficient of determination of cross-validation, (SEP) standard error of validation, and (R 2 val) coefficient of determination for external validation and coefficient of variation (CV). The prediction accuracy for pH, redox potential, electrical conductivity, moisture, TSS, and ash was good, while for free acidity and HMF it was poor. The results demonstrate that attenuated total reflectance-Fourier transform infrared spectrometry is a valuable, rapid, and nondestructive tool for the quantification of physicochemical properties of honey. PMID:28070445
Lohrer, Heinz; Nauck, Tanja
2009-10-30
Achilles tendinopathy is the predominant overuse injury in runners. To further investigate this overload injury in transverse and longitudinal studies a valid, responsive and reliable outcome measure is demanded. Most questionnaires have been developed for English-speaking populations. This is also true for the VISA-A score, so far representing the only valid, reliable, and disease specific questionnaire for Achilles tendinopathy. To internationally compare research results, to perform multinational studies or to exclude bias originating from subpopulations speaking different languages within one country an equivalent instrument is demanded in different languages. The aim of this study was therefore to cross-cultural adapt and validate the VISA-A questionnaire for German-speaking Achilles tendinopathy patients. According to the "guidelines for the process of cross-cultural adaptation of self-report measures" the VISA-A score was cross-culturally adapted into German (VISA-A-G) using six steps: Translation, synthesis, back translation, expert committee review, pretesting (n = 77), and appraisal of the adaptation process by an advisory committee determining the adequacy of the cross-cultural adaptation. The resulting VISA-A-G was then subjected to an analysis of reliability, validity, and internal consistency in 30 Achilles tendinopathy patients and 79 asymptomatic people. Concurrent validity was tested against a generic tendon grading system (Percy and Conochie) and against a classification system for the effect of pain on athletic performance (Curwin and Stanish). The "advisory committee" determined the VISA-A-G questionnaire as been translated "acceptable". The VISA-A-G questionnaire showed moderate to excellent test-retest reliability (ICC = 0.60 to 0.97). Concurrent validity showed good coherence when correlated with the grading system of Curwin and Stanish (rho = -0.95) and for the Percy and Conochie grade of severity (rho 0.95). Internal consistency (Cronbach's alpha) for the total VISA-A-G scores of the patients was calculated to be 0.737. The VISA-A questionnaire was successfully cross-cultural adapted and validated for use in German speaking populations. The psychometric properties of the VISA-A-G questionnaire are similar to those of the original English version. It therefore can be recommended as a sufficiently robust tool for future measuring clinical severity of Achilles tendinopathy in German speaking patients.
Cross-validation of an employee safety climate model in Malaysia.
Bahari, Siti Fatimah; Clarke, Sharon
2013-06-01
Whilst substantial research has investigated the nature of safety climate, and its importance as a leading indicator of organisational safety, much of this research has been conducted with Western industrial samples. The current study focuses on the cross-validation of a safety climate model in the non-Western industrial context of Malaysian manufacturing. The first-order factorial validity of Cheyne et al.'s (1998) [Cheyne, A., Cox, S., Oliver, A., Tomas, J.M., 1998. Modelling safety climate in the prediction of levels of safety activity. Work and Stress, 12(3), 255-271] model was tested, using confirmatory factor analysis, in a Malaysian sample. Results showed that the model fit indices were below accepted levels, indicating that the original Cheyne et al. (1998) safety climate model was not supported. An alternative three-factor model was developed using exploratory factor analysis. Although these findings are not consistent with previously reported cross-validation studies, we argue that previous studies have focused on validation across Western samples, and that the current study demonstrates the need to take account of cultural factors in the development of safety climate models intended for use in non-Western contexts. The results have important implications for the transferability of existing safety climate models across cultures (for example, in global organisations) and highlight the need for future research to examine cross-cultural issues in relation to safety climate. Copyright © 2013 National Safety Council and Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Pescarini, M.; Sinitsa, V.; Orsi, R.; Frisoni, M.
2013-03-01
This paper presents a synthesis of the ENEA-Bologna Nuclear Data Group programme dedicated to generate and validate group-wise cross section libraries for shielding and radiation damage deterministic calculations in nuclear fission reactors, following the data processing methodology recommended in the ANSI/ANS-6.1.2-1999 (R2009) American Standard. The VITJEFF311.BOLIB and VITENDF70.BOLIB finegroup coupled n-γ (199 n + 42 γ - VITAMIN-B6 structure) multi-purpose cross section libraries, based on the Bondarenko method for neutron resonance self-shielding and respectively on JEFF-3.1.1 and ENDF/B-VII.0 evaluated nuclear data, were produced in AMPX format using the NJOY-99.259 and the ENEA-Bologna 2007 Revision of the SCAMPI nuclear data processing systems. Two derived broad-group coupled n-γ (47 n + 20 γ - BUGLE-96 structure) working cross section libraries in FIDO-ANISN format for LWR shielding and pressure vessel dosimetry calculations, named BUGJEFF311.BOLIB and BUGENDF70.BOLIB, were generated by the revised version of SCAMPI, through problem-dependent cross section collapsing and self-shielding from the cited fine-group libraries. The validation results on the criticality safety benchmark experiments for the fine-group libraries and the preliminary validation results for the broad-group working libraries on the PCA-Replica and VENUS-3 engineering neutron shielding benchmark experiments are reported in synthesis.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chapman, Bryan Scott; Gough, Sean T.
This report documents a validation of the MCNP6 Version 1.0 computer code on the high performance computing platform Moonlight, for operations at Los Alamos National Laboratory (LANL) that involve plutonium metals, oxides, and solutions. The validation is conducted using the ENDF/B-VII.1 continuous energy group cross section library at room temperature. The results are for use by nuclear criticality safety personnel in performing analysis and evaluation of various facility activities involving plutonium materials.
How to test validity in orthodontic research: a mixed dentition analysis example.
Donatelli, Richard E; Lee, Shin-Jae
2015-02-01
The data used to test the validity of a prediction method should be different from the data used to generate the prediction model. In this study, we explored whether an independent data set is mandatory for testing the validity of a new prediction method and how validity can be tested without independent new data. Several validation methods were compared in an example using the data from a mixed dentition analysis with a regression model. The validation errors of real mixed dentition analysis data and simulation data were analyzed for increasingly large data sets. The validation results of both the real and the simulation studies demonstrated that the leave-1-out cross-validation method had the smallest errors. The largest errors occurred in the traditional simple validation method. The differences between the validation methods diminished as the sample size increased. The leave-1-out cross-validation method seems to be an optimal validation method for improving the prediction accuracy in a data set with limited sample sizes. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
Sobański, Jerzy A; Klasa, Katarzyna; Rutkowski, Krzysztof; Dembińska, Edyta; Müldner-Nieckowski, Łukasz; Cyranka, Katarzyna
2013-01-01
Assessment of reliability, cross-validity and usefulness in everyday clinical practice of two related tools: Social Avoidance and Distress Scale (SAD) and Fear of Negative Evaluation Scale (FNE). Analysis of tests results of 453 females and 172 males diagnosed in the years 2008-2010 in the Outpatient Clinic for Neurotic and Behavioral Disorders of the Cracow University Hospital, including, inter alia, results of the questionnaires SAD and FNE. The scales have been, with the consent of their authors (R. Friend) and the copyright holder (APA), translated into Polish and back-translated. Subjects also completed the symptom checklist KO '0'(n = 512), and neurotic personality questionnaire KON-2006 (n = 505), as well as the NEO-PI-R personality inventory (n = 46). The reliability and cross-validity coefficients of Polish versions were assessed in the patient population and their results were compared with those of the group of 75 medical students. The translation was verified by retranslation. The reliability coefficients of Polish version of the SAD and FNE scales turned out to be high--Cronbach's alpha coefficient was 0.94 for both scales, Guttman's split-half reliability coefficient 0.93. Correlations with symptom checklist KO '0 'and neurotic personality questionnaire KON-2006, as well as with the NEO -PI-R personality inventory were significant and indicate a good cross-validity of the analyzed tools. The average results in the patient population for both scales were significantly higher than the results in the preliminary control group of medical students. Polish versions of SAD and FNE questionnaires, like their other translations from English, proved to be reliable and have a high cross-validity with other original Polish tools used in the diagnosis of neurotic disorders, which allows to recommend them to be used in further studies, also in comparing healthy persons with those suffering from a variety of neurotic disorders.
NASA Astrophysics Data System (ADS)
Cánovas-García, Fulgencio; Alonso-Sarría, Francisco; Gomariz-Castillo, Francisco; Oñate-Valdivieso, Fernando
2017-06-01
Random forest is a classification technique widely used in remote sensing. One of its advantages is that it produces an estimation of classification accuracy based on the so called out-of-bag cross-validation method. It is usually assumed that such estimation is not biased and may be used instead of validation based on an external data-set or a cross-validation external to the algorithm. In this paper we show that this is not necessarily the case when classifying remote sensing imagery using training areas with several pixels or objects. According to our results, out-of-bag cross-validation clearly overestimates accuracy, both overall and per class. The reason is that, in a training patch, pixels or objects are not independent (from a statistical point of view) of each other; however, they are split by bootstrapping into in-bag and out-of-bag as if they were really independent. We believe that putting whole patch, rather than pixels/objects, in one or the other set would produce a less biased out-of-bag cross-validation. To deal with the problem, we propose a modification of the random forest algorithm to split training patches instead of the pixels (or objects) that compose them. This modified algorithm does not overestimate accuracy and has no lower predictive capability than the original. When its results are validated with an external data-set, the accuracy is not different from that obtained with the original algorithm. We analysed three remote sensing images with different classification approaches (pixel and object based); in the three cases reported, the modification we propose produces a less biased accuracy estimation.
Multinational Validation of the Spanish Bracken Basic Concept Scale for Cross-Cultural Assessments.
ERIC Educational Resources Information Center
Bracken, Bruce A.; And Others
1990-01-01
Investigated construct validity of the Spanish translation of the Bracken Basic Concept Scale (BBCS) in Latino children (n=293) including monolingual Spanish-speaking children from Puerto Rico and Venezuela and Spanish-dominant bilingual Latino children from Texas. Results provided support for construct validity of the Spanish version of the…
Bayesian cross-entropy methodology for optimal design of validation experiments
NASA Astrophysics Data System (ADS)
Jiang, X.; Mahadevan, S.
2006-07-01
An important concern in the design of validation experiments is how to incorporate the mathematical model in the design in order to allow conclusive comparisons of model prediction with experimental output in model assessment. The classical experimental design methods are more suitable for phenomena discovery and may result in a subjective, expensive, time-consuming and ineffective design that may adversely impact these comparisons. In this paper, an integrated Bayesian cross-entropy methodology is proposed to perform the optimal design of validation experiments incorporating the computational model. The expected cross entropy, an information-theoretic distance between the distributions of model prediction and experimental observation, is defined as a utility function to measure the similarity of two distributions. A simulated annealing algorithm is used to find optimal values of input variables through minimizing or maximizing the expected cross entropy. The measured data after testing with the optimum input values are used to update the distribution of the experimental output using Bayes theorem. The procedure is repeated to adaptively design the required number of experiments for model assessment, each time ensuring that the experiment provides effective comparison for validation. The methodology is illustrated for the optimal design of validation experiments for a three-leg bolted joint structure and a composite helicopter rotor hub component.
Kim, Seong-Hyeon; Goodman, Grace M; Toruno, Joseph A; Sherry, Alissa R; Kim, Hee Kyung
2015-10-01
We investigated the cross-cultural factorial validity of the three Higher-Order (H-O) scales in the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF) among a sample of North Korean female refugees (N = 2,732). Given the importance of the H-O scales in the overall structure of the MMPI-2-RF scales and in interpretation, we were interested in exploring their cross-cultural validity. We conducted an exploratory factor analysis (EFA) on the nine Restructured Clinical (RC) scale raw scores and fitted and compared one- to three-factor models. The three-factor model, akin to the model in Tellegen and Ben-Porath, demonstrated the best fit to the data. Furthermore, the pattern matrices of loadings across the current sample and the U.S. samples were comparable despite some differences, such as the RC2 scale's salient, negative loading on a factor analogous to the Behavioral/Externalizing Dysfunction scale. We also investigated the unique psychological characteristics of the refugees, possibly resulting from the arduous, perilous journeys out of North Korea taken by this group of female refugees and discussed the results of EFA in light of those singular psychological traits and experiences. Overall, the three H-O scales of the Korean MMPI-2-RF evidenced reasonable cross-cultural factorial validity among the sample of North Korean female refugees. © The Author(s) 2014.
Development of estrogen receptor beta binding prediction model using large sets of chemicals.
Sakkiah, Sugunadevi; Selvaraj, Chandrabose; Gong, Ping; Zhang, Chaoyang; Tong, Weida; Hong, Huixiao
2017-11-03
We developed an ER β binding prediction model to facilitate identification of chemicals specifically bind ER β or ER α together with our previously developed ER α binding model. Decision Forest was used to train ER β binding prediction model based on a large set of compounds obtained from EADB. Model performance was estimated through 1000 iterations of 5-fold cross validations. Prediction confidence was analyzed using predictions from the cross validations. Informative chemical features for ER β binding were identified through analysis of the frequency data of chemical descriptors used in the models in the 5-fold cross validations. 1000 permutations were conducted to assess the chance correlation. The average accuracy of 5-fold cross validations was 93.14% with a standard deviation of 0.64%. Prediction confidence analysis indicated that the higher the prediction confidence the more accurate the predictions. Permutation testing results revealed that the prediction model is unlikely generated by chance. Eighteen informative descriptors were identified to be important to ER β binding prediction. Application of the prediction model to the data from ToxCast project yielded very high sensitivity of 90-92%. Our results demonstrated ER β binding of chemicals could be accurately predicted using the developed model. Coupling with our previously developed ER α prediction model, this model could be expected to facilitate drug development through identification of chemicals that specifically bind ER β or ER α .
Measuring and Validating Neutron Capture Cross Sections Using a Lead Slowing-Down Spectrometer
NASA Astrophysics Data System (ADS)
Thompson, Nicholas
Accurate nuclear data is essential for the modeling, design, and operation of nuclear systems. In this work, the Rensselaer Polytechnic Institute (RPI) Lead Slowing-Down Spectrometer (LSDS) at the Gaerttner Linear Accelerator Center (LINAC) was used to measure neutron capture cross sections and validate capture cross sections in cross section libraries. The RPI LINAC was used to create a fast burst of neutrons in the center of the LSDS, a large cube of high purity lead. A sample and YAP:Ce scintillator were placed in the LSDS, and as neutrons lost energy through scattering interactions with the lead, the scintillator detected capture gammas resulting from neutron capture events in the sample. Samples of silver, gold, cobalt, iron, indium, molybdenum, niobium, nickel, tin, tantalum, and zirconium were measured. Data was collected as a function of time after neutron pulse, or slowing-down time, which is correlated to average neutron energy. An analog and a digital data acquisition system collected data simultaneously, allowing for collection of pulse shape information as well as timing. Collection of digital data allowed for pulse shape analysis after the experiment. This data was then analyzed and compared to Monte Carlo simulations to validate the accuracy of neutron capture cross section libraries. These measurements represent the first time that neutron capture cross sections have been measured using an LSDS in the United States, and the first time tools such as coincidence measurements and pulse height weighting have been applied to measurements of neutron capture cross sections using an LSDS. Significant differences between measurement results and simulation results were found in multiple materials, and some errors in nuclear data libraries have already been identified due to these measurements.
Mind your crossings: Mining GIS imagery for crosswalk localization.
Ahmetovic, Dragan; Manduchi, Roberto; Coughlan, James M; Mascetti, Sergio
2017-04-01
For blind travelers, finding crosswalks and remaining within their borders while traversing them is a crucial part of any trip involving street crossings. While standard Orientation & Mobility (O&M) techniques allow blind travelers to safely negotiate street crossings, additional information about crosswalks and other important features at intersections would be helpful in many situations, resulting in greater safety and/or comfort during independent travel. For instance, in planning a trip a blind pedestrian may wish to be informed of the presence of all marked crossings near a desired route. We have conducted a survey of several O&M experts from the United States and Italy to determine the role that crosswalks play in travel by blind pedestrians. The results show stark differences between survey respondents from the U.S. compared with Italy: the former group emphasized the importance of following standard O&M techniques at all legal crossings (marked or unmarked), while the latter group strongly recommended crossing at marked crossings whenever possible. These contrasting opinions reflect differences in the traffic regulations of the two countries and highlight the diversity of needs that travelers in different regions may have. To address the challenges faced by blind pedestrians in negotiating street crossings, we devised a computer vision-based technique that mines existing spatial image databases for discovery of zebra crosswalks in urban settings. Our algorithm first searches for zebra crosswalks in satellite images; all candidates thus found are validated against spatially registered Google Street View images. This cascaded approach enables fast and reliable discovery and localization of zebra crosswalks in large image datasets. While fully automatic, our algorithm can be improved by a final crowdsourcing validation. To this end, we developed a Pedestrian Crossing Human Validation (PCHV) web service, which supports crowdsourcing to rule out false positives and identify false negatives.
Mind your crossings: Mining GIS imagery for crosswalk localization
Ahmetovic, Dragan; Manduchi, Roberto; Coughlan, James M.; Mascetti, Sergio
2017-01-01
For blind travelers, finding crosswalks and remaining within their borders while traversing them is a crucial part of any trip involving street crossings. While standard Orientation & Mobility (O&M) techniques allow blind travelers to safely negotiate street crossings, additional information about crosswalks and other important features at intersections would be helpful in many situations, resulting in greater safety and/or comfort during independent travel. For instance, in planning a trip a blind pedestrian may wish to be informed of the presence of all marked crossings near a desired route. We have conducted a survey of several O&M experts from the United States and Italy to determine the role that crosswalks play in travel by blind pedestrians. The results show stark differences between survey respondents from the U.S. compared with Italy: the former group emphasized the importance of following standard O&M techniques at all legal crossings (marked or unmarked), while the latter group strongly recommended crossing at marked crossings whenever possible. These contrasting opinions reflect differences in the traffic regulations of the two countries and highlight the diversity of needs that travelers in different regions may have. To address the challenges faced by blind pedestrians in negotiating street crossings, we devised a computer vision-based technique that mines existing spatial image databases for discovery of zebra crosswalks in urban settings. Our algorithm first searches for zebra crosswalks in satellite images; all candidates thus found are validated against spatially registered Google Street View images. This cascaded approach enables fast and reliable discovery and localization of zebra crosswalks in large image datasets. While fully automatic, our algorithm can be improved by a final crowdsourcing validation. To this end, we developed a Pedestrian Crossing Human Validation (PCHV) web service, which supports crowdsourcing to rule out false positives and identify false negatives. PMID:28757907
Sattler, Tine; Sekulic, Damir; Spasic, Miodrag; Osmankac, Nedzad; Vicente João, Paulo; Dervisevic, Edvin; Hadzic, Vedran
2016-01-01
Previous investigations noted potential importance of isokinetic strength in rapid muscular performances, such as jumping. This study aimed to identify the influence of isokinetic-knee-strength on specific jumping performance in volleyball. The secondary aim of the study was to evaluate reliability and validity of the two volleyball-specific jumping tests. The sample comprised 67 female (21.96±3.79 years; 68.26±8.52 kg; 174.43±6.85 cm) and 99 male (23.62±5.27 years; 84.83±10.37 kg; 189.01±7.21 cm) high- volleyball players who competed in 1st and 2nd National Division. Subjects were randomly divided into validation (N.=55 and 33 for males and females, respectively) and cross-validation subsamples (N.=54 and 34 for males and females, respectively). Set of predictors included isokinetic tests, to evaluate the eccentric and concentric strength capacities of the knee extensors, and flexors for dominant and non-dominant leg. The main outcome measure for the isokinetic testing was peak torque (PT) which was later normalized for body mass and expressed as PT/Kg. Block-jump and spike-jump performances were measured over three trials, and observed as criteria. Forward stepwise multiple regressions were calculated for validation subsamples and then cross-validated. Cross validation included correlations between and t-test differences between observed and predicted scores; and Bland Altman graphics. Jumping tests were found to be reliable (spike jump: ICC of 0.79 and 0.86; block-jump: ICC of 0.86 and 0.90; for males and females, respectively), and their validity was confirmed by significant t-test differences between 1st vs. 2nd division players. Isokinetic variables were found to be significant predictors of jumping performance in females, but not among males. In females, the isokinetic-knee measures were shown to be stronger and more valid predictors of the block-jump (42% and 64% of the explained variance for validation and cross-validation subsample, respectively) than that of the spike-jump (39% and 34% of the explained variance for validation and cross-validation subsample, respectively). Differences between prediction models calculated for males and females are mostly explained by gender-specific biomechanics of jumping. Study defined importance of knee-isokinetic-strength in volleyball jumping performance in female athletes. Further studies should evaluate association between ankle-isokinetic-strength and volleyball-specific jumping performances. Results reinforce the need for the cross-validation of the prediction-models in sport and exercise sciences.
Validation of tungsten cross sections in the neutron energy region up to 100 keV
NASA Astrophysics Data System (ADS)
Pigni, Marco T.; Žerovnik, Gašper; Leal, Luiz. C.; Trkov, Andrej
2017-09-01
Following a series of recent cross section evaluations on tungsten isotopes performed at Oak Ridge National Laboratory (ORNL), this paper presents the validation work carried out to test the performance of the evaluated cross sections based on lead-slowing-down (LSD) benchmarks conducted in Grenoble. ORNL completed the resonance parameter evaluation of four tungsten isotopes - 182,183,184,186W - in August 2014 and submitted it as an ENDF-compatible file to be part of the next release of the ENDF/B-VIII.0 nuclear data library. The evaluations were performed with support from the US Nuclear Criticality Safety Program in an effort to provide improved tungsten cross section and covariance data for criticality safety sensitivity analyses. The validation analysis based on the LSD benchmarks showed an improved agreement with the experimental response when the ORNL tungsten evaluations were included in the ENDF/B-VII.1 library. Comparison with the results obtained with the JEFF-3.2 nuclear data library are also discussed.
Cross validation issues in multiobjective clustering
Brusco, Michael J.; Steinley, Douglas
2018-01-01
The implementation of multiobjective programming methods in combinatorial data analysis is an emergent area of study with a variety of pragmatic applications in the behavioural sciences. Most notably, multiobjective programming provides a tool for analysts to model trade offs among competing criteria in clustering, seriation, and unidimensional scaling tasks. Although multiobjective programming has considerable promise, the technique can produce numerically appealing results that lack empirical validity. With this issue in mind, the purpose of this paper is to briefly review viable areas of application for multiobjective programming and, more importantly, to outline the importance of cross-validation when using this method in cluster analysis. PMID:19055857
Efficient strategies for leave-one-out cross validation for genomic best linear unbiased prediction.
Cheng, Hao; Garrick, Dorian J; Fernando, Rohan L
2017-01-01
A random multiple-regression model that simultaneously fit all allele substitution effects for additive markers or haplotypes as uncorrelated random effects was proposed for Best Linear Unbiased Prediction, using whole-genome data. Leave-one-out cross validation can be used to quantify the predictive ability of a statistical model. Naive application of Leave-one-out cross validation is computationally intensive because the training and validation analyses need to be repeated n times, once for each observation. Efficient Leave-one-out cross validation strategies are presented here, requiring little more effort than a single analysis. Efficient Leave-one-out cross validation strategies is 786 times faster than the naive application for a simulated dataset with 1,000 observations and 10,000 markers and 99 times faster with 1,000 observations and 100 markers. These efficiencies relative to the naive approach using the same model will increase with increases in the number of observations. Efficient Leave-one-out cross validation strategies are presented here, requiring little more effort than a single analysis.
Bernhard, Gerda; Knibbe, Ronald A.; von Wolff, Alessa; Dingoyan, Demet; Schulz, Holger; Mösko, Mike
2015-01-01
Background Cultural competence of healthcare professionals (HCPs) is recognized as a strategy to reduce cultural disparities in healthcare. However, standardised, valid and reliable instruments to assess HCPs’ cultural competence are notably lacking. The present study aims to 1) identify the core components of cultural competence from a healthcare perspective, 2) to develop a self-report instrument to assess cultural competence of HCPs and 3) to evaluate the psychometric properties of the new instrument. Methods The conceptual model and initial item pool, which were applied to the cross-cultural competence instrument for the healthcare profession (CCCHP), were derived from an expert survey (n = 23), interviews with HCPs (n = 12), and a broad narrative review on assessment instruments and conceptual models of cultural competence. The item pool was reduced systematically, which resulted in a 59-item instrument. A sample of 336 psychologists, in advanced psychotherapeutic training, and 409 medical students participated, in order to evaluate the construct validity and reliability of the CCCHP. Results Construct validity was supported by principal component analysis, which led to a 32-item six-component solution with 50% of the total variance explained. The different dimensions of HCPs’ cultural competence are: Cross-Cultural Motivation/Curiosity, Cross-Cultural Attitudes, Cross-Cultural Skills, Cross-Cultural Knowledge/Awareness and Cross-Cultural Emotions/Empathy. For the total instrument, the internal consistency reliability was .87 and the dimension’s Cronbach’s α ranged from .54 to .84. The discriminating power of the CCCHP was indicated by statistically significant mean differences in CCCHP subscale scores between predefined groups. Conclusions The 32-item CCCHP exhibits acceptable psychometric properties, particularly content and construct validity to examine HCPs’ cultural competence. The CCCHP with its five dimensions offers a comprehensive assessment of HCPs’ cultural competence, and has the ability to distinguish between groups that are expected to differ in cultural competence. This instrument can foster professional development through systematic self-assessment and thus contributes to improve the quality of patient care. PMID:26641876
ERIC Educational Resources Information Center
Schmidt, Silke; Power, Mick
2006-01-01
Recent projects on international instrument development have produced a wide array of health indicators that may be used for cross-cultural field-testing, however more information on their cross-cultural performance in relation to health determinants is necessary. The current study approaches one step for international conceptual validation by…
Wang, Wenyi; Kim, Marlene T.; Sedykh, Alexander
2015-01-01
Purpose Experimental Blood–Brain Barrier (BBB) permeability models for drug molecules are expensive and time-consuming. As alternative methods, several traditional Quantitative Structure-Activity Relationship (QSAR) models have been developed previously. In this study, we aimed to improve the predictivity of traditional QSAR BBB permeability models by employing relevant public bio-assay data in the modeling process. Methods We compiled a BBB permeability database consisting of 439 unique compounds from various resources. The database was split into a modeling set of 341 compounds and a validation set of 98 compounds. Consensus QSAR modeling workflow was employed on the modeling set to develop various QSAR models. A five-fold cross-validation approach was used to validate the developed models, and the resulting models were used to predict the external validation set compounds. Furthermore, we used previously published membrane transporter models to generate relevant transporter profiles for target compounds. The transporter profiles were used as additional biological descriptors to develop hybrid QSAR BBB models. Results The consensus QSAR models have R2=0.638 for fivefold cross-validation and R2=0.504 for external validation. The consensus model developed by pooling chemical and transporter descriptors showed better predictivity (R2=0.646 for five-fold cross-validation and R2=0.526 for external validation). Moreover, several external bio-assays that correlate with BBB permeability were identified using our automatic profiling tool. Conclusions The BBB permeability models developed in this study can be useful for early evaluation of new compounds (e.g., new drug candidates). The combination of chemical and biological descriptors shows a promising direction to improve the current traditional QSAR models. PMID:25862462
Avelino, Patrick Roberto; Magalhães, Lívia Castro; Faria-Fortini, Iza; Basílio, Marluce Lopes; Menezes, Kênia Kiefer Parreiras; Teixeira-Salmela, Luci Fuscaldi
2018-06-01
The purpose of this study was to evaluate the cross-cultural validity of the Brazilian version of the ABILOCO questionnaire for stroke subjects. Cross-cultural adaptation of the original English version of the ABILOCO to the Brazilian-Portuguese language followed standardized procedures. The adapted version was administered to 136 stroke subjects and its measurement properties were assessed using Rash analysis. Cross-cultural validity was based on cultural invariance analyses. Goodness-of-fit analysis revealed one misfitting item. The principal component analysis of the residuals showed that the first dimension explained 45% of the variance in locomotion ability; however, the eigenvalue was 1.92. The ABILOCO-Brazil divided the sample into two levels of ability and the items into about seven levels of difficulty. The item-person map showed some ceiling effect. Cultural invariance analyses revealed that although there were differences in the item calibrations between the ABILOCO-original and ABILOCO-Brazil, they did not impact the measures of locomotion ability. The ABILOCO-Brazil demonstrated satisfactory measurement properties to be used within both clinical and research contexts in Brazil, as well cross-cultural validity to be used in international/multicentric studies. However, the presence of ceiling effect suggests that it may not be appropriate for the assessment of individuals with high levels of locomotion ability. Implications for rehabilitation Self-report measures of locomotion ability are clinically important, since they describe the abilities of the individuals within real life contexts. The ABILOCO questionnaire, specific for stroke survivors, demonstrated satisfactory measurement properties, but may not be most appropriate to assess individuals with high levels of locomotion ability The results of the cross-cultural validity showed that the ABILOCO-Original and the ABILOCO-Brazil calibrations may be used interchangeable.
Kerlinger's Criterial Referents Theory Revisited.
ERIC Educational Resources Information Center
Zak, Itai; Birenbaum, Menucha
1980-01-01
Kerlinger's criterial referents theory of attitudes was tested cross-culturally by administering an education attitude referents summated-rating scale to 713 individuals in Israel. The response pattern to criterial and noncriterial referents was examined. Results indicated empirical cross-cultural validity of theory, but questioned measuring…
Cross-Cultural Applicability of the Montreal Cognitive Assessment (MoCA): A Systematic Review.
O'Driscoll, Ciarán; Shaikh, Madiha
2017-01-01
The Montreal Cognitive Assessment (MoCA) is widely used to screen for mild cognitive impairment (MCI). While there are many available versions, the cross-cultural validity of the assessment has not been explored sufficiently. We aimed to interrogate the validity of the MoCA in a cross-cultural context: in differentiating MCI from normal controls (NC); and identifying cut-offs and adjustments for age and education where possible. This review sourced a wide range of studies including case-control studies. In addition, we report findings for differentiating dementias from NC and MCI from dementias, however, these were not considered to be an appropriate use of the MoCA. The subject of the review assumes heterogeneity and therefore meta-analyses was not conducted. Quality ratings, forest plots of validated studies (sensitivity and specificity) with covariates (suggested cut-offs, age, education and country), and summary receiver operating characteristic curve are presented. The results showed a wide range in suggested cutoffs for MCI cross-culturally, with variability in levels of sensitivity and specificity ranging from low to high. Poor methodological rigor appears to have affected reported accuracy and validity of the MoCA. The review highlights the necessity for cross-cultural considerations when using the MoCA, and recognizing it as a screen and not a diagnostic tool. Appropriate cutoffs and point adjustments for education are suggested.
Blagus, Rok; Lusa, Lara
2015-11-04
Prediction models are used in clinical research to develop rules that can be used to accurately predict the outcome of the patients based on some of their characteristics. They represent a valuable tool in the decision making process of clinicians and health policy makers, as they enable them to estimate the probability that patients have or will develop a disease, will respond to a treatment, or that their disease will recur. The interest devoted to prediction models in the biomedical community has been growing in the last few years. Often the data used to develop the prediction models are class-imbalanced as only few patients experience the event (and therefore belong to minority class). Prediction models developed using class-imbalanced data tend to achieve sub-optimal predictive accuracy in the minority class. This problem can be diminished by using sampling techniques aimed at balancing the class distribution. These techniques include under- and oversampling, where a fraction of the majority class samples are retained in the analysis or new samples from the minority class are generated. The correct assessment of how the prediction model is likely to perform on independent data is of crucial importance; in the absence of an independent data set, cross-validation is normally used. While the importance of correct cross-validation is well documented in the biomedical literature, the challenges posed by the joint use of sampling techniques and cross-validation have not been addressed. We show that care must be taken to ensure that cross-validation is performed correctly on sampled data, and that the risk of overestimating the predictive accuracy is greater when oversampling techniques are used. Examples based on the re-analysis of real datasets and simulation studies are provided. We identify some results from the biomedical literature where the incorrect cross-validation was performed, where we expect that the performance of oversampling techniques was heavily overestimated.
Dewitt, James; Capistrant, Benjamin; Kohli, Nidhi; Mitteldorf, Darryl; Merengwa, Enyinnaya; West, William
2018-01-01
Background While deduplication and cross-validation protocols have been recommended for large Web-based studies, protocols for survey response validation of smaller studies have not been published. Objective This paper reports the challenges of survey validation inherent in a small Web-based health survey research. Methods The subject population was North American, gay and bisexual, prostate cancer survivors, who represent an under-researched, hidden, difficult-to-recruit, minority-within-a-minority population. In 2015-2016, advertising on a large Web-based cancer survivor support network, using email and social media, yielded 478 completed surveys. Results Our manual deduplication and cross-validation protocol identified 289 survey submissions (289/478, 60.4%) as likely spam, most stemming from advertising on social media. The basic components of this deduplication and validation protocol are detailed. An unexpected challenge encountered was invalid survey responses evolving across the study period. This necessitated the static detection protocol be augmented with a dynamic one. Conclusions Five recommendations for validation of Web-based samples, especially with smaller difficult-to-recruit populations, are detailed. PMID:29691203
ERIC Educational Resources Information Center
Song, Ji Hoon; Kim, Jin Yong; Chermack, Thomas J.; Yang; Baiyin
2008-01-01
The primary purpose of this research was to adapt the Dimensions of Learning Organization Questionnaire (DLOQ) from Watkins and Marsick (1993, 1996) and examine its validity and reliability in a Korean context. Results indicate that the DLOQ produces valid and reliable scores of learning organization characteristics in a Korean cultural context.…
Mapping the Diagnosis Axis of an Interface Terminology to the NANDA International Taxonomy
Juvé Udina, Maria-Eulàlia; Gonzalez Samartino, Maribel; Matud Calvo, Cristina
2012-01-01
Background. Nursing terminologies are designed to support nursing practice but, as with any other clinical tool, they should be evaluated. Cross-mapping is a formal method for examining the validity of the existing controlled vocabularies. Objectives. The study aims to assess the inclusiveness and expressiveness of the nursing diagnosis axis of a newly implemented interface terminology by cross-mapping with the NANDA-I taxonomy. Design/Methods. The study applied a descriptive design, using a cross-sectional, bidirectional mapping strategy. The sample included 728 concepts from both vocabularies. Concept cross-mapping was carried out to identify one-to-one, negative, and hierarchical connections. The analysis was conducted using descriptive statistics. Results. Agreement of the raters' mapping achieved 97%. More than 60% of the nursing diagnosis concepts in the NANDA-I taxonomy were mapped to concepts in the diagnosis axis of the new interface terminology; 71.1% were reversely mapped. Conclusions. Main results for outcome measures suggest that the diagnosis axis of this interface terminology meets the validity criterion of cross-mapping when mapped from and to the NANDA-I taxonomy. PMID:22830046
Mapping the Diagnosis Axis of an Interface Terminology to the NANDA International Taxonomy.
Juvé Udina, Maria-Eulàlia; Gonzalez Samartino, Maribel; Matud Calvo, Cristina
2012-01-01
Background. Nursing terminologies are designed to support nursing practice but, as with any other clinical tool, they should be evaluated. Cross-mapping is a formal method for examining the validity of the existing controlled vocabularies. Objectives. The study aims to assess the inclusiveness and expressiveness of the nursing diagnosis axis of a newly implemented interface terminology by cross-mapping with the NANDA-I taxonomy. Design/Methods. The study applied a descriptive design, using a cross-sectional, bidirectional mapping strategy. The sample included 728 concepts from both vocabularies. Concept cross-mapping was carried out to identify one-to-one, negative, and hierarchical connections. The analysis was conducted using descriptive statistics. Results. Agreement of the raters' mapping achieved 97%. More than 60% of the nursing diagnosis concepts in the NANDA-I taxonomy were mapped to concepts in the diagnosis axis of the new interface terminology; 71.1% were reversely mapped. Conclusions. Main results for outcome measures suggest that the diagnosis axis of this interface terminology meets the validity criterion of cross-mapping when mapped from and to the NANDA-I taxonomy.
Translation, cross-cultural adaptation and validation of the Diabetes Empowerment Scale – Short Form
Chaves, Fernanda Figueredo; Reis, Ilka Afonso; Pagano, Adriana Silvina; Torres, Heloísa de Carvalho
2017-01-01
ABSTRACT OBJECTIVE To translate, cross-culturally adapt and validate the Diabetes Empowerment Scale – Short Form for assessment of psychosocial self-efficacy in diabetes care within the Brazilian cultural context. METHODS Assessment of the instrument’s conceptual equivalence, as well as its translation and cross-cultural adaptation were performed following international standards. The Expert Committee’s assessment of the translated version was conducted through a web questionnaire developed and applied via the web tool e-Surv. The cross-culturally adapted version was used for the pre-test, which was carried out via phone call in a group of eleven health care service users diagnosed with type 2 diabetes mellitus. The pre-test results were examined by a group of experts, composed by health care consultants, applied linguists and statisticians, aiming at an adequate version of the instrument, which was subsequently used for test and retest in a sample of 100 users diagnosed with type 2 diabetes mellitus via phone call, their answers being recorded by the web tool e-Surv. Internal consistency and reproducibility of analysis were carried out within the statistical programming environment R. RESULTS Face and content validity were attained and the Brazilian Portuguese version, entitled Escala de Autoeficácia em Diabetes – Versão Curta, was established. The scale had acceptable internal consistency with Cronbach’s alpha of 0.634 (95%CI 0.494– 0.737), while the correlation of the total score in the two periods was considered moderate (0.47). The intraclass correlation coefficient was 0.50. CONCLUSIONS The translated and cross-culturally adapted version of the instrument to spoken Brazilian Portuguese was considered valid and reliable to be used for assessment within the Brazilian population diagnosed with type 2 diabetes mellitus. The use of a web tool (e-Surv) for recording the Expert Committee responses as well as the responses in the validation tests proved to be a reliable, safe and innovative method. PMID:28355337
The development and cross-validation of an MMPI typology of murderers.
Holcomb, W R; Adams, N A; Ponder, H M
1985-06-01
A sample of 80 male offenders charged with premeditated murder were divided into five personality types using MMPI scores. A hierarchical clustering procedure was used with a subsequent internal cross-validation analysis using a second sample of 80 premeditated murderers. A Discriminant Analysis resulted in a 96.25% correct classification of subjects from the second sample into the five types. Clinical data from a mental status interview schedule supported the external validity of these types. There were significant differences among the five types in hallucinations, disorientation, hostility, depression, and paranoid thinking. Both similarities and differences of the present typology with prior research was discussed. Additional research questions were suggested.
Design and Implementation of a Smart Home System Using Multisensor Data Fusion Technology.
Hsu, Yu-Liang; Chou, Po-Huan; Chang, Hsing-Cheng; Lin, Shyan-Lung; Yang, Shih-Chin; Su, Heng-Yi; Chang, Chih-Chien; Cheng, Yuan-Sheng; Kuo, Yu-Chen
2017-07-15
This paper aims to develop a multisensor data fusion technology-based smart home system by integrating wearable intelligent technology, artificial intelligence, and sensor fusion technology. We have developed the following three systems to create an intelligent smart home environment: (1) a wearable motion sensing device to be placed on residents' wrists and its corresponding 3D gesture recognition algorithm to implement a convenient automated household appliance control system; (2) a wearable motion sensing device mounted on a resident's feet and its indoor positioning algorithm to realize an effective indoor pedestrian navigation system for smart energy management; (3) a multisensor circuit module and an intelligent fire detection and alarm algorithm to realize a home safety and fire detection system. In addition, an intelligent monitoring interface is developed to provide in real-time information about the smart home system, such as environmental temperatures, CO concentrations, communicative environmental alarms, household appliance status, human motion signals, and the results of gesture recognition and indoor positioning. Furthermore, an experimental testbed for validating the effectiveness and feasibility of the smart home system was built and verified experimentally. The results showed that the 3D gesture recognition algorithm could achieve recognition rates for automated household appliance control of 92.0%, 94.8%, 95.3%, and 87.7% by the 2-fold cross-validation, 5-fold cross-validation, 10-fold cross-validation, and leave-one-subject-out cross-validation strategies. For indoor positioning and smart energy management, the distance accuracy and positioning accuracy were around 0.22% and 3.36% of the total traveled distance in the indoor environment. For home safety and fire detection, the classification rate achieved 98.81% accuracy for determining the conditions of the indoor living environment.
Design and Implementation of a Smart Home System Using Multisensor Data Fusion Technology
Chou, Po-Huan; Chang, Hsing-Cheng; Lin, Shyan-Lung; Yang, Shih-Chin; Su, Heng-Yi; Chang, Chih-Chien; Cheng, Yuan-Sheng; Kuo, Yu-Chen
2017-01-01
This paper aims to develop a multisensor data fusion technology-based smart home system by integrating wearable intelligent technology, artificial intelligence, and sensor fusion technology. We have developed the following three systems to create an intelligent smart home environment: (1) a wearable motion sensing device to be placed on residents’ wrists and its corresponding 3D gesture recognition algorithm to implement a convenient automated household appliance control system; (2) a wearable motion sensing device mounted on a resident’s feet and its indoor positioning algorithm to realize an effective indoor pedestrian navigation system for smart energy management; (3) a multisensor circuit module and an intelligent fire detection and alarm algorithm to realize a home safety and fire detection system. In addition, an intelligent monitoring interface is developed to provide in real-time information about the smart home system, such as environmental temperatures, CO concentrations, communicative environmental alarms, household appliance status, human motion signals, and the results of gesture recognition and indoor positioning. Furthermore, an experimental testbed for validating the effectiveness and feasibility of the smart home system was built and verified experimentally. The results showed that the 3D gesture recognition algorithm could achieve recognition rates for automated household appliance control of 92.0%, 94.8%, 95.3%, and 87.7% by the 2-fold cross-validation, 5-fold cross-validation, 10-fold cross-validation, and leave-one-subject-out cross-validation strategies. For indoor positioning and smart energy management, the distance accuracy and positioning accuracy were around 0.22% and 3.36% of the total traveled distance in the indoor environment. For home safety and fire detection, the classification rate achieved 98.81% accuracy for determining the conditions of the indoor living environment. PMID:28714884
2012-01-01
Background The purpose of this study was to examine the internal consistency, test-retest reliability, construct validity and predictive validity of a new German self-report instrument to assess the influence of social support and the physical environment on physical activity in adolescents. Methods Based on theoretical consideration, the short scales on social support and physical environment were developed and cross-validated in two independent study samples of 9 to 17 year-old girls and boys. The longitudinal sample of Study I (n = 196) was recruited from a German comprehensive school, and subjects in this study completed the questionnaire twice with a between-test interval of seven days. Cronbach’s alphas were computed to determine the internal consistency of the factors. Test-retest reliability of the latent factors was assessed using intra-class coefficients. Factorial validity of the scales was assessed using principle components analysis. Construct validity was determined using a cross-validation technique by performing confirmatory factor analysis with the independent nationwide cross-sectional sample of Study II (n = 430). Correlations between factors and three measures of physical activity (objectively measured moderate-to-vigorous physical activity (MVPA), self-reported habitual MVPA and self-reported recent MVPA) were calculated to determine the predictive validity of the instrument. Results Construct validity of the social support scale (two factors: parental support and peer support) and the physical environment scale (four factors: convenience, public recreation facilities, safety and private sport providers) was shown. Both scales had moderate test-retest reliability. The factors of the social support scale also had good internal consistency and predictive validity. Internal consistency and predictive validity of the physical environment scale were low to acceptable. Conclusions The results of this study indicate moderate to good reliability and construct validity of the social support scale and physical environment scale. Predictive validity was only confirmed for the social support scale but not for the physical environment scale. Hence, it remains unclear if a person’s physical environment has a direct or an indirect effect on physical activity behavior or a moderation function. PMID:22928865
Waples, Robin S
2010-07-01
Recognition of the importance of cross-validation ('any technique or instance of assessing how the results of a statistical analysis will generalize to an independent dataset'; Wiktionary, en.wiktionary.org) is one reason that the U.S. Securities and Exchange Commission requires all investment products to carry some variation of the disclaimer, 'Past performance is no guarantee of future results.' Even a cursory examination of financial behaviour, however, demonstrates that this warning is regularly ignored, even by those who understand what an independent dataset is. In the natural sciences, an analogue to predicting future returns for an investment strategy is predicting power of a particular algorithm to perform with new data. Once again, the key to developing an unbiased assessment of future performance is through testing with independent data--that is, data that were in no way involved in developing the method in the first place. A 'gold-standard' approach to cross-validation is to divide the data into two parts, one used to develop the algorithm, the other used to test its performance. Because this approach substantially reduces the sample size that can be used in constructing the algorithm, researchers often try other variations of cross-validation to accomplish the same ends. As illustrated by Anderson in this issue of Molecular Ecology Resources, however, not all attempts at cross-validation produce the desired result. Anderson used simulated data to evaluate performance of several software programs designed to identify subsets of loci that can be effective for assigning individuals to population of origin based on multilocus genetic data. Such programs are likely to become increasingly popular as researchers seek ways to streamline routine analyses by focusing on small sets of loci that contain most of the desired signal. Anderson found that although some of the programs made an attempt at cross-validation, all failed to meet the 'gold standard' of using truly independent data and therefore produced overly optimistic assessments of power of the selected set of loci--a phenomenon known as 'high grading bias.'
NASA Astrophysics Data System (ADS)
Fix, A.; Ehret, G.; Flentje, H.; Poberaj, G.; Gottwald, M.; Finkenzeller, H.; Bremer, H.; Bruns, M.; Burrows, J. P.; Kleinböhl, A.; Küllmann, H.; Kuttippurath, J.; Richter, A.; Wang, P.; Heue, K.-P.; Platt, U.; Wagner, T.
2004-12-01
For the first time three different remote sensing instruments - a sub-millimeter radiometer, a differential optical absorption spectrometer in the UV-visible spectral range, and a lidar - were deployed aboard DLR's meteorological research aircraft Falcon 20 to validate a large number of SCIAMACHY level 2 and off-line data products such as O3, NO2, N2O, BrO, OClO, H2O, aerosols, and clouds. Within two main validation campaigns of the SCIA-VALUE mission (SCIAMACHY VALidation and Utilization Experiment) extended latitudinal cross-sections stretching from polar regions to the tropics as well as longitudinal cross sections at polar latitudes at about 70° N and the equator have been generated. This contribution gives an overview over the campaigns performed and reports on the observation strategy for achieving the validation goals. We also emphasize the synergetic use of the novel set of aircraft instrumentation and the usefulness of this innovative suite of remote sensing instruments for satellite validation.
NASA Astrophysics Data System (ADS)
Fix, A.; Ehret, G.; Flentje, H.; Poberaj, G.; Gottwald, M.; Finkenzeller, H.; Bremer, H.; Bruns, M.; Burrows, J. P.; Kleinböhl, A.; Küllmann, H.; Kuttippurath, J.; Richter, A.; Wang, P.; Heue, K.-P.; Platt, U.; Pundt, I.; Wagner, T.
2005-05-01
For the first time three different remote sensing instruments - a sub-millimeter radiometer, a differential optical absorption spectrometer in the UV-visible spectral range, and a lidar - were deployed aboard DLR's meteorological research aircraft Falcon 20 to validate a large number of SCIAMACHY level 2 and off-line data products such as O3, NO2, N2O, BrO, OClO, H2O, aerosols, and clouds. Within two validation campaigns of the SCIA-VALUE mission (SCIAMACHY VALidation and Utilization Experiment) extended latitudinal cross-sections stretching from polar regions to the tropics as well as longitudinal cross sections at polar latitudes at about 70° N and the equator were generated. This contribution gives an overview over the campaigns performed and reports on the observation strategy for achieving the validation goals. We also emphasize the synergetic use of the novel set of aircraft instrumentation and the usefulness of this innovative suite of remote sensing instruments for satellite validation.
Validation of Cross Sections for Monte Carlo Simulation of the Photoelectric Effect
NASA Astrophysics Data System (ADS)
Han, Min Cheol; Kim, Han Sung; Pia, Maria Grazia; Basaglia, Tullio; Batič, Matej; Hoff, Gabriela; Kim, Chan Hyeong; Saracco, Paolo
2016-04-01
Several total and partial photoionization cross section calculations, based on both theoretical and empirical approaches, are quantitatively evaluated with statistical analyses using a large collection of experimental data retrieved from the literature to identify the state of the art for modeling the photoelectric effect in Monte Carlo particle transport. Some of the examined cross section models are available in general purpose Monte Carlo systems, while others have been implemented and subjected to validation tests for the first time to estimate whether they could improve the accuracy of particle transport codes. The validation process identifies Scofield's 1973 non-relativistic calculations, tabulated in the Evaluated Photon Data Library (EPDL), as the one best reproducing experimental measurements of total cross sections. Specialized total cross section models, some of which derive from more recent calculations, do not provide significant improvements. Scofield's non-relativistic calculations are not surpassed regarding the compatibility with experiment of K and L shell photoionization cross sections either, although in a few test cases Ebel's parameterization produces more accurate results close to absorption edges. Modifications to Biggs and Lighthill's parameterization implemented in Geant4 significantly reduce the accuracy of total cross sections at low energies with respect to its original formulation. The scarcity of suitable experimental data hinders a similar extensive analysis for the simulation of the photoelectron angular distribution, which is limited to a qualitative appraisal.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mbah, Chamberlain, E-mail: chamberlain.mbah@ugent.be; Department of Mathematical Modeling, Statistics, and Bioinformatics, Faculty of Bioscience Engineering, Ghent University, Ghent; Thierens, Hubert
Purpose: To identify the main causes underlying the failure of prediction models for radiation therapy toxicity to replicate. Methods and Materials: Data were used from two German cohorts, Individual Radiation Sensitivity (ISE) (n=418) and Mammary Carcinoma Risk Factor Investigation (MARIE) (n=409), of breast cancer patients with similar characteristics and radiation therapy treatments. The toxicity endpoint chosen was telangiectasia. The LASSO (least absolute shrinkage and selection operator) logistic regression method was used to build a predictive model for a dichotomized endpoint (Radiation Therapy Oncology Group/European Organization for the Research and Treatment of Cancer score 0, 1, or ≥2). Internal areas undermore » the receiver operating characteristic curve (inAUCs) were calculated by a naïve approach whereby the training data (ISE) were also used for calculating the AUC. Cross-validation was also applied to calculate the AUC within the same cohort, a second type of inAUC. Internal AUCs from cross-validation were calculated within ISE and MARIE separately. Models trained on one dataset (ISE) were applied to a test dataset (MARIE) and AUCs calculated (exAUCs). Results: Internal AUCs from the naïve approach were generally larger than inAUCs from cross-validation owing to overfitting the training data. Internal AUCs from cross-validation were also generally larger than the exAUCs, reflecting heterogeneity in the predictors between cohorts. The best models with largest inAUCs from cross-validation within both cohorts had a number of common predictors: hypertension, normalized total boost, and presence of estrogen receptors. Surprisingly, the effect (coefficient in the prediction model) of hypertension on telangiectasia incidence was positive in ISE and negative in MARIE. Other predictors were also not common between the 2 cohorts, illustrating that overcoming overfitting does not solve the problem of replication failure of prediction models completely. Conclusions: Overfitting and cohort heterogeneity are the 2 main causes of replication failure of prediction models across cohorts. Cross-validation and similar techniques (eg, bootstrapping) cope with overfitting, but the development of validated predictive models for radiation therapy toxicity requires strategies that deal with cohort heterogeneity.« less
ERIC Educational Resources Information Center
Acar, Tu¨lin
2014-01-01
In literature, it has been observed that many enhanced criteria are limited by factor analysis techniques. Besides examinations of statistical structure and/or psychological structure, such validity studies as cross validation and classification-sequencing studies should be performed frequently. The purpose of this study is to examine cross…
Mills, Tamara L; Holm, Margo B; Schmeler, Mark
2007-01-01
The purpose of this study was to establish the test-retest reliability and content validity of an outcomes tool designed to measure the effectiveness of seating-mobility interventions on the functional performance of individuals who use wheelchairs or scooters as their primary seating-mobility device. The instrument, Functioning Everyday With a Wheelchair (FEW), is a questionnaire designed to measure perceived user function related to wheelchair/scooter use. Using consumer-generated items, FEW Beta Version 1.0 was developed and test-retest reliability was established. Cross-validation of FEW Beta Version 1.0 was then carried out with five samples of seating-mobility users to establish content validity. Based on the content validity study, FEW Version 2.0 was developed and administered to seating-mobility consumers to examine its test-retest reliability. FEW Beta Version 1.0 yielded an intraclass correlation coefficient (ICC) Model (3,k) of .92, p < .001, and the content validity results revealed that FEW Beta Version 1.0 captured 55% of seating-mobility goals reported by consumers across five samples. FEW Version 2.0 yielded ICC(3,k) = .86, p < .001, and captured 98.5% of consumers' seating-mobility goals. The cross-validation study identified new categories of seating-mobility goals for inclusion in FEW Version 2.0, and the content validity of FEW Version 2.0 was confirmed. FEW Beta Version 1.0 and FEW Version 2.0 were highly stable in their measurement of participants' seating-mobility goals over a 1-week interval.
Castillo-Tandazo, Wilson; Flores-Fortty, Adolfo; Feraud, Lourdes; Tettamanti, Daniel
2013-01-01
Purpose To translate, cross-culturally adapt, and validate the Questionnaire for Diabetes-Related Foot Disease (Q-DFD), originally created and validated in Australia, for its use in Spanish-speaking patients with diabetes mellitus. Patients and methods The translation and cross-cultural adaptation were based on international guidelines. The Spanish version of the survey was applied to a community-based (sample A) and a hospital clinic-based sample (samples B and C). Samples A and B were used to determine criterion and construct validity comparing the survey findings with clinical evaluation and medical records, respectively; while sample C was used to determine intra- and inter-rater reliability. Results After completing the rigorous translation process, only four items were considered problematic and required a new translation. In total, 127 patients were included in the validation study: 76 to determine criterion and construct validity and 41 to establish intra- and inter-rater reliability. For an overall diagnosis of diabetes-related foot disease, a substantial level of agreement was obtained when we compared the Q-DFD with the clinical assessment (kappa 0.77, sensitivity 80.4%, specificity 91.5%, positive likelihood ratio [LR+] 9.46, negative likelihood ratio [LR−] 0.21); while an almost perfect level of agreement was obtained when it was compared with medical records (kappa 0.88, sensitivity 87%, specificity 97%, LR+ 29.0, LR− 0.13). Survey reliability showed substantial levels of agreement, with kappa scores of 0.63 and 0.73 for intra- and inter-rater reliability, respectively. Conclusion The translated and cross-culturally adapted Q-DFD showed good psychometric properties (validity, reproducibility, and reliability) that allow its use in Spanish-speaking diabetic populations. PMID:24039434
2017-01-01
Objective To perform a translation and cross-cultural adaptation of the Cardiac Rehabilitation Barriers Scale (CRBS) for use in Korea, followed by psychometric validation. The CRBS was developed to assess patients' perception of the degree to which patient, provider and health system-level barriers affect their cardiac rehabilitation (CR) participation. Methods The CRBS consists of 21 items (barriers to adherence) rated on a 5-point Likert scale. The first phase was to translate and cross-culturally adapt the CRBS to the Korean language. After back-translation, both versions were reviewed by a committee. The face validity was assessed in a sample of Korean patients (n=53) with history of acute myocardial infarction that did not participate in CR through semi-structured interviews. The second phase was to assess the construct and criterion validity of the Korean translation as well as internal reliability, through administration of the translated version in 104 patients, principle component analysis with varimax rotation and cross-referencing against CR use, respectively. Results The length, readability, and clarity of the questionnaire were rated well, demonstrating face validity. Analysis revealed a six-factor solution, demonstrating construct validity. Cronbach's alpha was greater than 0.65. Barriers rated highest included not knowing about CR and not being contacted by a program. The mean CRBS score was significantly higher among non-attendees (2.71±0.26) than CR attendees (2.51±0.18) (p<0.01). Conclusion The Korean version of CRBS has demonstrated face, content and criterion validity, suggesting it may be useful for assessing barriers to CR utilization in Korea. PMID:29201826
Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J. Sunil
2015-01-01
PRIMsrc is a novel implementation of a non-parametric bump hunting procedure, based on the Patient Rule Induction Method (PRIM), offering a unified treatment of outcome variables, including censored time-to-event (Survival), continuous (Regression) and discrete (Classification) responses. To fit the model, it uses a recursive peeling procedure with specific peeling criteria and stopping rules depending on the response. To validate the model, it provides an objective function based on prediction-error or other specific statistic, as well as two alternative cross-validation techniques, adapted to the task of decision-rule making and estimation in the three types of settings. PRIMsrc comes as an open source R package, including at this point: (i) a main function for fitting a Survival Bump Hunting model with various options allowing cross-validated model selection to control model size (#covariates) and model complexity (#peeling steps) and generation of cross-validated end-point estimates; (ii) parallel computing; (iii) various S3-generic and specific plotting functions for data visualization, diagnostic, prediction, summary and display of results. It is available on CRAN and GitHub. PMID:26798326
Cross-Validating Chinese Language Mental Health Recovery Measures in Hong Kong
ERIC Educational Resources Information Center
Bola, John; Chan, Tiffany Hill Ching; Chen, Eric HY; Ng, Roger
2016-01-01
Objectives: Promoting recovery in mental health services is hampered by a shortage of reliable and valid measures, particularly in Hong Kong. We seek to cross validate two Chinese language measures of recovery and one of recovery-promoting environments. Method: A cross-sectional survey of people recovering from early episode psychosis (n = 121)…
Ávila, Christiane Wahast; Riegel, Barbara; Pokorski, Simoni Chiarelli; Camey, Suzi; Silveira, Luana Claudia Jacoby; Rabelo-Silva, Eneida Rejane
2013-01-01
Objective. To adapt and evaluate the psychometric properties of the Brazilian version of the SCHFI v 6.2. Methods. With the approval of the original author, we conducted a complete cross-cultural adaptation of the instrument (translation, synthesis, back translation, synthesis of back translation, expert committee review, and pretesting). The adapted version was named Brazilian version of the self-care of heart failure index v 6.2. The psychometric properties assessed were face validity and content validity (by expert committee review), construct validity (convergent validity and confirmatory factor analysis), and reliability. Results. Face validity and content validity were indicative of semantic, idiomatic, experimental, and conceptual equivalence. Convergent validity was demonstrated by a significant though moderate correlation (r = −0.51) on comparison with equivalent question scores of the previously validated Brazilian European heart failure self-care behavior scale. Confirmatory factor analysis supported the original three-factor model as having the best fit, although similar results were obtained for inadequate fit indices. The reliability of the instrument, as expressed by Cronbach's alpha, was 0.40, 0.82, and 0.93 for the self-care maintenance, self-care management, and self-care confidence scales, respectively. Conclusion. The SCHFI v 6.2 was successfully adapted for use in Brazil. Nevertheless, further studies should be carried out to improve its psychometric properties. PMID:24163765
Tannure, Meire Chucre; Salgado, Patrícia de Oliveira; Chianca, Tânia Couto Machado
2014-01-01
This descriptive study aimed at elaborating nursing diagnostic labels according to ICNP®; conducting a cross-mapping between the diagnostic formulations and the diagnostic labels of NANDA-I; identifying the diagnostic labels thus obtained that were also listed in the NANDA-I; and mapping them according to Basic Human Needs. The workshop technique was applied to 32 intensive care nurses, the cross-mapping and validation based on agreement with experts. The workshop produced 1665 diagnostic labels which were further refined into 120 labels. They were then submitted to a cross-mapping process with both NANDA-I diagnostic labels and the Basic Human Needs. The mapping results underwent content validation by two expert nurses leading to concordance rates of 92% and 100%. It was found that 63 labels were listed in NANDA-I and 47 were not.
NASA Astrophysics Data System (ADS)
Haddad, Khaled; Rahman, Ataur; A Zaman, Mohammad; Shrestha, Surendra
2013-03-01
SummaryIn regional hydrologic regression analysis, model selection and validation are regarded as important steps. Here, the model selection is usually based on some measurements of goodness-of-fit between the model prediction and observed data. In Regional Flood Frequency Analysis (RFFA), leave-one-out (LOO) validation or a fixed percentage leave out validation (e.g., 10%) is commonly adopted to assess the predictive ability of regression-based prediction equations. This paper develops a Monte Carlo Cross Validation (MCCV) technique (which has widely been adopted in Chemometrics and Econometrics) in RFFA using Generalised Least Squares Regression (GLSR) and compares it with the most commonly adopted LOO validation approach. The study uses simulated and regional flood data from the state of New South Wales in Australia. It is found that when developing hydrologic regression models, application of the MCCV is likely to result in a more parsimonious model than the LOO. It has also been found that the MCCV can provide a more realistic estimate of a model's predictive ability when compared with the LOO.
Empirical Performance of Cross-Validation With Oracle Methods in a Genomics Context.
Martinez, Josue G; Carroll, Raymond J; Müller, Samuel; Sampson, Joshua N; Chatterjee, Nilanjan
2011-11-01
When employing model selection methods with oracle properties such as the smoothly clipped absolute deviation (SCAD) and the Adaptive Lasso, it is typical to estimate the smoothing parameter by m-fold cross-validation, for example, m = 10. In problems where the true regression function is sparse and the signals large, such cross-validation typically works well. However, in regression modeling of genomic studies involving Single Nucleotide Polymorphisms (SNP), the true regression functions, while thought to be sparse, do not have large signals. We demonstrate empirically that in such problems, the number of selected variables using SCAD and the Adaptive Lasso, with 10-fold cross-validation, is a random variable that has considerable and surprising variation. Similar remarks apply to non-oracle methods such as the Lasso. Our study strongly questions the suitability of performing only a single run of m-fold cross-validation with any oracle method, and not just the SCAD and Adaptive Lasso.
NASA Astrophysics Data System (ADS)
Xin, L.; Markine, V. L.; Shevtsov, I. Y.
2016-03-01
A three-dimensional (3-D) explicit dynamic finite element (FE) model is developed to simulate the impact of the wheel on the crossing nose. The model consists of a wheel set moving over the turnout crossing. Realistic wheel, wing rail and crossing geometries have been used in the model. Using this model the dynamic responses of the system such as the contact forces between the wheel and the crossing, crossing nose displacements and accelerations, stresses in rail material as well as in sleepers and ballast can be obtained. Detailed analysis of the wheel set and crossing interaction using the local contact stress state in the rail is possible as well, which provides a good basis for prediction of the long-term behaviour of the crossing (fatigue analysis). In order to tune and validate the FE model field measurements conducted on several turnouts in the railway network in the Netherlands are used here. The parametric study including variations of the crossing nose geometries performed here demonstrates the capabilities of the developed model. The results of the validation and parametric study are presented and discussed.
Guidelines to validate control of cross-contamination during washing of fresh-cut leafy vegetables
USDA-ARS?s Scientific Manuscript database
The U.S. Food and Drug Administration requires food processors to implement and validate processes that will result in significantly minimizing or preventing the occurrence of hazards that are likely to occur in food production. During production of fresh-cut leafy vegetables, microbial contaminati...
Dynamic Time Warping compared to established methods for validation of musculoskeletal models.
Gaspar, Martin; Welke, Bastian; Seehaus, Frank; Hurschler, Christof; Schwarze, Michael
2017-04-11
By means of Multi-Body musculoskeletal simulation, important variables such as internal joint forces and moments can be estimated which cannot be measured directly. Validation can ensued by qualitative or by quantitative methods. Especially when comparing time-dependent signals, many methods do not perform well and validation is often limited to qualitative approaches. The aim of the present study was to investigate the capabilities of the Dynamic Time Warping (DTW) algorithm for comparing time series, which can quantify phase as well as amplitude errors. We contrast the sensitivity of DTW with other established metrics: the Pearson correlation coefficient, cross-correlation, the metric according to Geers, RMSE and normalized RMSE. This study is based on two data sets, where one data set represents direct validation and the other represents indirect validation. Direct validation was performed in the context of clinical gait-analysis on trans-femoral amputees fitted with a 6 component force-moment sensor. Measured forces and moments from amputees' socket-prosthesis are compared to simulated forces and moments. Indirect validation was performed in the context of surface EMG measurements on a cohort of healthy subjects with measurements taken of seven muscles of the leg, which were compared to simulated muscle activations. Regarding direct validation, a positive linear relation between results of RMSE and nRMSE to DTW can be seen. For indirect validation, a negative linear relation exists between Pearson correlation and cross-correlation. We propose the DTW algorithm for use in both direct and indirect quantitative validation as it correlates well with methods that are most suitable for one of the tasks. However, in DV it should be used together with methods resulting in a dimensional error value, in order to be able to interpret results more comprehensible. Copyright © 2017 Elsevier Ltd. All rights reserved.
A Swedish cross-cultural adaptation and validation of the Tinnitus Functional Index.
Hoff, Maria; Kähäri, Kim
2017-04-01
The Tinnitus Functional Index (TFI) is a recent self-report instrument for tinnitus with potential advantages over other existing instruments, including a demonstrated high responsiveness. The objectives of this study were to translate and cross-culturally adapt the TFI into Swedish and to investigate its validity and reliability. The development of the Swedish version (TFI-SE) followed published guidelines on cross-cultural adaptation of health questionnaires. Validity and reliability was investigated by correlating responses on the TFI-SE with other tinnitus measures [Tinnitus Handicap Inventory (THI) and visual analogue scale (VAS)] and a scale measuring anxiety and depression (HADS). Consecutively recruited tinnitus patients (n = 100) from four Swedish clinics completed the questionnaires. The mean age of the sample was 51 years (SD =17). The internal consistency of the TFI-SE was good (α = 0.95) and the test-retest reliability was high (ICC =0.93). Our results supported the eight-factor structure proposed for the original TFI, and a high correlation between the TFI-SE and the THI (r = 0.8; p < 0.01) and lower correlations between the TFI-SE and the HADS-D (r = 0.60; p < 0.01) and HADS-A (r = 0.59; p < 0.01) confirmed satisfactory convergent and discriminant validity. We found that the Swedish translation and cross-cultural adaptation of the TFI is valid and reliable for use with adult tinnitus patients.
Kaneko, Hiromasa; Funatsu, Kimito
2013-09-23
We propose predictive performance criteria for nonlinear regression models without cross-validation. The proposed criteria are the determination coefficient and the root-mean-square error for the midpoints between k-nearest-neighbor data points. These criteria can be used to evaluate predictive ability after the regression models are updated, whereas cross-validation cannot be performed in such a situation. The proposed method is effective and helpful in handling big data when cross-validation cannot be applied. By analyzing data from numerical simulations and quantitative structural relationships, we confirm that the proposed criteria enable the predictive ability of the nonlinear regression models to be appropriately quantified.
Benchmarking protein classification algorithms via supervised cross-validation.
Kertész-Farkas, Attila; Dhir, Somdutta; Sonego, Paolo; Pacurar, Mircea; Netoteia, Sergiu; Nijveen, Harm; Kuzniar, Arnold; Leunissen, Jack A M; Kocsor, András; Pongor, Sándor
2008-04-24
Development and testing of protein classification algorithms are hampered by the fact that the protein universe is characterized by groups vastly different in the number of members, in average protein size, similarity within group, etc. Datasets based on traditional cross-validation (k-fold, leave-one-out, etc.) may not give reliable estimates on how an algorithm will generalize to novel, distantly related subtypes of the known protein classes. Supervised cross-validation, i.e., selection of test and train sets according to the known subtypes within a database has been successfully used earlier in conjunction with the SCOP database. Our goal was to extend this principle to other databases and to design standardized benchmark datasets for protein classification. Hierarchical classification trees of protein categories provide a simple and general framework for designing supervised cross-validation strategies for protein classification. Benchmark datasets can be designed at various levels of the concept hierarchy using a simple graph-theoretic distance. A combination of supervised and random sampling was selected to construct reduced size model datasets, suitable for algorithm comparison. Over 3000 new classification tasks were added to our recently established protein classification benchmark collection that currently includes protein sequence (including protein domains and entire proteins), protein structure and reading frame DNA sequence data. We carried out an extensive evaluation based on various machine-learning algorithms such as nearest neighbor, support vector machines, artificial neural networks, random forests and logistic regression, used in conjunction with comparison algorithms, BLAST, Smith-Waterman, Needleman-Wunsch, as well as 3D comparison methods DALI and PRIDE. The resulting datasets provide lower, and in our opinion more realistic estimates of the classifier performance than do random cross-validation schemes. A combination of supervised and random sampling was used to construct model datasets, suitable for algorithm comparison.
NASA Astrophysics Data System (ADS)
Gutiérrez, Jose Manuel; Maraun, Douglas; Widmann, Martin; Huth, Radan; Hertig, Elke; Benestad, Rasmus; Roessler, Ole; Wibig, Joanna; Wilcke, Renate; Kotlarski, Sven
2016-04-01
VALUE is an open European network to validate and compare downscaling methods for climate change research (http://www.value-cost.eu). A key deliverable of VALUE is the development of a systematic validation framework to enable the assessment and comparison of both dynamical and statistical downscaling methods. This framework is based on a user-focused validation tree, guiding the selection of relevant validation indices and performance measures for different aspects of the validation (marginal, temporal, spatial, multi-variable). Moreover, several experiments have been designed to isolate specific points in the downscaling procedure where problems may occur (assessment of intrinsic performance, effect of errors inherited from the global models, effect of non-stationarity, etc.). The list of downscaling experiments includes 1) cross-validation with perfect predictors, 2) GCM predictors -aligned with EURO-CORDEX experiment- and 3) pseudo reality predictors (see Maraun et al. 2015, Earth's Future, 3, doi:10.1002/2014EF000259, for more details). The results of these experiments are gathered, validated and publicly distributed through the VALUE validation portal, allowing for a comprehensive community-open downscaling intercomparison study. In this contribution we describe the overall results from Experiment 1), consisting of a European wide 5-fold cross-validation (with consecutive 6-year periods from 1979 to 2008) using predictors from ERA-Interim to downscale precipitation and temperatures (minimum and maximum) over a set of 86 ECA&D stations representative of the main geographical and climatic regions in Europe. As a result of the open call for contribution to this experiment (closed in Dec. 2015), over 40 methods representative of the main approaches (MOS and Perfect Prognosis, PP) and techniques (linear scaling, quantile mapping, analogs, weather typing, linear and generalized regression, weather generators, etc.) were submitted, including information both data (downscaled values) and metadata (characterizing different aspects of the downscaling methods). This constitutes the largest and most comprehensive to date intercomparison of statistical downscaling methods. Here, we present an overall validation, analyzing marginal and temporal aspects to assess the intrinsic performance and added value of statistical downscaling methods at both annual and seasonal levels. This validation takes into account the different properties/limitations of different approaches and techniques (as reported in the provided metadata) in order to perform a fair comparison. It is pointed out that this experiment alone is not sufficient to evaluate the limitations of (MOS) bias correction techniques. Moreover, it also does not fully validate PP since we don't learn whether we have the right predictors and whether the PP assumption is valid. These problems will be analyzed in the subsequent community-open VALUE experiments 2) and 3), which will be open for participation along the present year.
Bullinger, Monika; Quitmann, Julia; Silva, Neuza; Rohenkohl, Anja; Chaplin, John E; DeBusk, Kendra; Mimoun, Emmanuelle; Feigerlova, Eva; Herdman, Michael; Sanz, Dolores; Wollmann, Hartmut; Pleil, Andreas; Power, Michael
2014-01-01
Testing cross-cultural equivalence of patient-reported outcomes requires sufficiently large samples per country, which is difficult to achieve in rare endocrine paediatric conditions. We describe a novel approach to cross-cultural testing of the Quality of Life in Short Stature Youth (QoLISSY) questionnaire in five countries by sequentially taking one country out (TOCO) from the total sample and iteratively comparing the resulting psychometric performance. Development of the QoLISSY proceeded from focus group discussions through pilot testing to field testing in 268 short-statured patients and their parents. To explore cross-cultural equivalence, the iterative TOCO technique was used to examine and compare the validity, reliability, and convergence of patient and parent responses on QoLISSY in the field test dataset, and to predict QoLISSY scores from clinical, socio-demographic and psychosocial variables. Validity and reliability indicators were satisfactory for each sample after iteratively omitting one country. Comparisons with the total sample revealed cross-cultural equivalence in internal consistency and construct validity for patients and parents, high inter-rater agreement and a substantial proportion of QoLISSY variance explained by predictors. The TOCO technique is a powerful method to overcome problems of country-specific testing of patient-reported outcome instruments. It provides an empirical support to QoLISSY's cross-cultural equivalence and is recommended for future research.
Cross-validating a bidimensional mathematics anxiety scale.
Haiyan Bai
2011-03-01
The psychometric properties of a 14-item bidimensional Mathematics Anxiety Scale-Revised (MAS-R) were empirically cross-validated with two independent samples consisting of 647 secondary school students. An exploratory factor analysis on the scale yielded strong construct validity with a clear two-factor structure. The results from a confirmatory factor analysis indicated an excellent model-fit (χ(2) = 98.32, df = 62; normed fit index = .92, comparative fit index = .97; root mean square error of approximation = .04). The internal consistency (.85), test-retest reliability (.71), interfactor correlation (.26, p < .001), and positive discrimination power indicated that MAS-R is a psychometrically reliable and valid instrument for measuring mathematics anxiety. Math anxiety, as measured by MAS-R, correlated negatively with student achievement scores (r = -.38), suggesting that MAS-R may be a useful tool for classroom teachers and other educational personnel tasked with identifying students at risk of reduced math achievement because of anxiety.
Steen, Valerie; Sofaer, Helen R.; Skagen, Susan K.; Ray, Andrea J.; Noon, Barry R
2017-01-01
Species distribution models (SDMs) are commonly used to assess potential climate change impacts on biodiversity, but several critical methodological decisions are often made arbitrarily. We compare variability arising from these decisions to the uncertainty in future climate change itself. We also test whether certain choices offer improved skill for extrapolating to a changed climate and whether internal cross-validation skill indicates extrapolative skill. We compared projected vulnerability for 29 wetland-dependent bird species breeding in the climatically dynamic Prairie Pothole Region, USA. For each species we built 1,080 SDMs to represent a unique combination of: future climate, class of climate covariates, collinearity level, and thresholding procedure. We examined the variation in projected vulnerability attributed to each uncertainty source. To assess extrapolation skill under a changed climate, we compared model predictions with observations from historic drought years. Uncertainty in projected vulnerability was substantial, and the largest source was that of future climate change. Large uncertainty was also attributed to climate covariate class with hydrological covariates projecting half the range loss of bioclimatic covariates or other summaries of temperature and precipitation. We found that choices based on performance in cross-validation improved skill in extrapolation. Qualitative rankings were also highly uncertain. Given uncertainty in projected vulnerability and resulting uncertainty in rankings used for conservation prioritization, a number of considerations appear critical for using bioclimatic SDMs to inform climate change mitigation strategies. Our results emphasize explicitly selecting climate summaries that most closely represent processes likely to underlie ecological response to climate change. For example, hydrological covariates projected substantially reduced vulnerability, highlighting the importance of considering whether water availability may be a more proximal driver than precipitation. However, because cross-validation results were correlated with extrapolation results, the use of cross-validation performance metrics to guide modeling choices where knowledge is limited was supported.
Steen, Valerie; Sofaer, Helen R; Skagen, Susan K; Ray, Andrea J; Noon, Barry R
2017-11-01
Species distribution models (SDMs) are commonly used to assess potential climate change impacts on biodiversity, but several critical methodological decisions are often made arbitrarily. We compare variability arising from these decisions to the uncertainty in future climate change itself. We also test whether certain choices offer improved skill for extrapolating to a changed climate and whether internal cross-validation skill indicates extrapolative skill. We compared projected vulnerability for 29 wetland-dependent bird species breeding in the climatically dynamic Prairie Pothole Region, USA. For each species we built 1,080 SDMs to represent a unique combination of: future climate, class of climate covariates, collinearity level, and thresholding procedure. We examined the variation in projected vulnerability attributed to each uncertainty source. To assess extrapolation skill under a changed climate, we compared model predictions with observations from historic drought years. Uncertainty in projected vulnerability was substantial, and the largest source was that of future climate change. Large uncertainty was also attributed to climate covariate class with hydrological covariates projecting half the range loss of bioclimatic covariates or other summaries of temperature and precipitation. We found that choices based on performance in cross-validation improved skill in extrapolation. Qualitative rankings were also highly uncertain. Given uncertainty in projected vulnerability and resulting uncertainty in rankings used for conservation prioritization, a number of considerations appear critical for using bioclimatic SDMs to inform climate change mitigation strategies. Our results emphasize explicitly selecting climate summaries that most closely represent processes likely to underlie ecological response to climate change. For example, hydrological covariates projected substantially reduced vulnerability, highlighting the importance of considering whether water availability may be a more proximal driver than precipitation. However, because cross-validation results were correlated with extrapolation results, the use of cross-validation performance metrics to guide modeling choices where knowledge is limited was supported.
Baldwin, Carol M.; Choi, Myunghan; McClain, Darya Bonds; Celaya, Alma; Quan, Stuart F.
2012-01-01
Study Objectives: To translate, back-translate and cross-language validate (English/Spanish) the Sleep Heart Health Study Sleep Habits Questionnaire for use with Spanish-speakers in clinical and research settings. Methods: Following rigorous translation and back-translation, this cross-sectional cross-language validation study recruited bilingual participants from academic, clinic, and community-based settings (N = 50; 52% women; mean age 38.8 ± 12 years; 90% of Mexican heritage). Participants completed English and Spanish versions of the Sleep Habits Questionnaire, the Epworth Sleepiness Scale, and the Acculturation Rating Scale for Mexican Americans II one week apart in randomized order. Psychometric properties were assessed, including internal consistency, convergent validity, scale equivalence, language version intercorrelations, and exploratory factor analysis using PASW (Version18) software. Grade level readability of the sleep measure was evaluated. Results: All sleep categories (duration, snoring, apnea, insomnia symptoms, other sleep symptoms, sleep disruptors, restless legs syndrome) showed Cronbach α, Spearman-Brown coefficients and intercorrelations ≥ 0.700, suggesting robust internal consistency, correlation, and agreement between language versions. The Epworth correlated significantly with snoring, apnea, sleep symptoms, restless legs, and sleep disruptors) on both versions, supporting convergent validity. Items loaded on 4 factors accounted for 68% and 67% of the variance on the English and Spanish versions, respectively. Conclusions: The Spanish-language Sleep Habits Questionnaire demonstrates conceptual and content equivalency. It has appropriate measurement properties and should be useful for assessing sleep health in community-based clinics and intervention studies among Spanish-speaking Mexican Americans. Both language versions showed readability at the fifth grade level. Further testing is needed with larger samples. Citation: Baldwin CM; Choi M; McClain DB; Celaya A; Quan SF. Spanish translation and cross-language validation of a Sleep Habits Questionnaire for use in clinical and research settings. J Clin Sleep Med 2012;8(2):137-146. PMID:22505858
[Traceability of Wine Varieties Using Near Infrared Spectroscopy Combined with Cyclic Voltammetry].
Li, Meng-hua; Li, Jing-ming; Li, Jun-hui; Zhang, Lu-da; Zhao, Long-lian
2015-06-01
To achieve the traceability of wine varieties, a method was proposed to fuse Near-infrared (NIR) spectra and cyclic voltammograms (CV) which contain different information using D-S evidence theory. NIR spectra and CV curves of three different varieties of wines (cabernet sauvignon, merlot, cabernet gernischt) which come from seven different geographical origins were collected separately. The discriminant models were built using PLS-DA method. Based on this, D-S evidence theory was then applied to achieve the integration of the two kinds of discrimination results. After integrated by D-S evidence theory, the accuracy rate of cross-validation is 95.69% and validation set is 94.12% for wine variety identification. When only considering the wine that come from Yantai, the accuracy rate of cross-validation is 99.46% and validation set is 100%. All the traceability models after fusion achieved better results on classification than individual method. These results suggest that the proposed method combining electrochemical information with spectral information using the D-S evidence combination formula is benefit to the improvement of model discrimination effect, and is a promising tool for discriminating different kinds of wines.
NASA Astrophysics Data System (ADS)
Battistella, C.; Robinson, D.; McQuarrie, N.; Ghoshal, S.
2017-12-01
Multiple valid balanced cross sections can be produced from mapped surface and subsurface data. By integrating low temperature thermochronologic data, we are better able to predict subsurface geometries. Existing valid balanced cross section for far western Nepal are few (Robinson et al., 2006) and do not incorporate thermochronologic data because the data did not exist. The data published along the Simikot cross section along the Karnali River since then include muscovite Ar, zircon U-Th/He and apatite fission track. We present new mapping and a new valid balanced cross section that takes into account the new field data as well as the limitations that thermochronologic data places on the kinematics of the cross section. Additional constrains include some new geomorphology data acquired since 2006 that indicate areas of increased vertical uplift, which indicate locations of buried ramps in the Main Himalayan thrust and guide the locations of Lesser Himalayan ramps in the balanced cross section. Future work will include flexural modeling, new low temperature thermochronometic data, and 2-D thermokinematic models from a sequentially forward modeled balanced cross sections in far western Nepal.
Scale for positive aspects of caregiving experience: development, reliability, and factor structure.
Kate, N; Grover, S; Kulhara, P; Nehra, R
2012-06-01
OBJECTIVE. To develop an instrument (Scale for Positive Aspects of Caregiving Experience [SPACE]) that evaluates positive caregiving experience and assess its psychometric properties. METHODS. Available scales which assess some aspects of positive caregiving experience were reviewed and a 50-item questionnaire with a 5-point rating was constructed. In all, 203 primary caregivers of patients with severe mental disorders were asked to complete the questionnaire. Internal consistency, test-retest reliability, cross-language reliability, split-half reliability, and face validity were evaluated. Principal component factor analysis was run to assess the factorial validity of the scale. RESULTS. The scale developed as part of the study was found to have good internal consistency, test-retest reliability, cross-language reliability, split-half reliability, and face validity. Principal component factor analysis yielded a 4-factor structure, which also had good test-retest reliability and cross-language reliability. There was a strong correlation between the 4 factors obtained. CONCLUSION. The SPACE developed as part of this study has good psychometric properties.
de Klerk, Susan; Buchanan, Helen; Jerosch-Herold, Christina
Systematic review. The Disabilities of the Arm Shoulder and Hand Questionnaire has multiple language versions from many countries around the world. In addition there is extensive research evidence of its psychometric properties. The purpose of this study was to systematically review the evidence available on the validity and clinical utility of the Disabilities of the Arm Shoulder and Hand as a measure of activity and participation in patients with musculoskeletal hand injuries in developing country contexts. We registered the review with international prospective register of systematic reviews prior to conducting a comprehensive literature search and extracting descriptive data. Two reviewers independently assessed methodological quality with the Consensus-Based Standards for the Selection of Health Measurement Instruments critical appraisal tool, the checklist to operationalize measurement characteristics of patient-rated outcome measures and the multidimensional model of clinical utility. Fourteen studies reporting 12 language versions met the eligibility criteria. Two language versions (Persian and Turkish) had an overall rating of good, and one (Thai) had an overall rating of excellent for cross-cultural validity. The remaining 9 language versions had an overall poor rating for cross-cultural validity. Content and construct validity and clinical utility yielded similar results. Poor quality ratings for validity and clinical utility were due to insufficient documentation of results and inadequate psychometric testing. With the increase in migration and globalization, hand therapists are likely to require a range of culturally adapted and translated versions of the Disabilities of the Arm Shoulder and Hand. Recommendations include rigorous application and reporting of cross-cultural adaptation, appropriate psychometric testing, and testing of clinical utility in routine clinical practice. Copyright © 2017 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.
Indicators of Ecological Change
2005-03-01
Vine 0.07 0.26 Yellow Jasmine LM Gymnopogon ambiguus Graminae Cryptophyte Geophyte Grass 0.17 0.45 Beard grass RLD Haplopappus divaricatus Asteraceae...cross-validation procedure. The cross-validation analysis 7 determines the percentage of observations correctly classified. In essence , a cross-8
Empirical Performance of Cross-Validation With Oracle Methods in a Genomics Context
Martinez, Josue G.; Carroll, Raymond J.; Müller, Samuel; Sampson, Joshua N.; Chatterjee, Nilanjan
2012-01-01
When employing model selection methods with oracle properties such as the smoothly clipped absolute deviation (SCAD) and the Adaptive Lasso, it is typical to estimate the smoothing parameter by m-fold cross-validation, for example, m = 10. In problems where the true regression function is sparse and the signals large, such cross-validation typically works well. However, in regression modeling of genomic studies involving Single Nucleotide Polymorphisms (SNP), the true regression functions, while thought to be sparse, do not have large signals. We demonstrate empirically that in such problems, the number of selected variables using SCAD and the Adaptive Lasso, with 10-fold cross-validation, is a random variable that has considerable and surprising variation. Similar remarks apply to non-oracle methods such as the Lasso. Our study strongly questions the suitability of performing only a single run of m-fold cross-validation with any oracle method, and not just the SCAD and Adaptive Lasso. PMID:22347720
Cross-Validation of Predictor Equations for Armor Crewman Performance
1980-01-01
Technical Report 447 CROSS-VALIDATION OF PREDICTOR EQUATIONS FOR ARMOR CREWMAN PERFORMANCE Anthony J. Maitland , Newell K. Eaton, and Janet F. Neft...ORG. REPORT NUMBER Anthony J/ Maitland . Newell K/EatorV. and B OTATO RN UBR. 9- PERFORMING ORGANIZATION NAME AND ADDRESS I0. PROGRAM ELEMENT, PROJECT...Technical Report 447 CROSS-VALIDATION OF PREDICTOR EQUATIONS FOR ARMOR CREWMAN PERFORMANCE Anthony J. Maitland , Newell K. Eaton, Accession For and
Statistical validation of normal tissue complication probability models.
Xu, Cheng-Jian; van der Schaaf, Arjen; Van't Veld, Aart A; Langendijk, Johannes A; Schilstra, Cornelis
2012-09-01
To investigate the applicability and value of double cross-validation and permutation tests as established statistical approaches in the validation of normal tissue complication probability (NTCP) models. A penalized regression method, LASSO (least absolute shrinkage and selection operator), was used to build NTCP models for xerostomia after radiation therapy treatment of head-and-neck cancer. Model assessment was based on the likelihood function and the area under the receiver operating characteristic curve. Repeated double cross-validation showed the uncertainty and instability of the NTCP models and indicated that the statistical significance of model performance can be obtained by permutation testing. Repeated double cross-validation and permutation tests are recommended to validate NTCP models before clinical use. Copyright © 2012 Elsevier Inc. All rights reserved.
Chen, Po-Yi; Yang, Chien-Ming; Morin, Charles M
2015-05-01
The purpose of this study is to examine the factor structure of the Insomnia Severity Index (ISI) across samples recruited from different countries. We tried to identify the most appropriate factor model for the ISI and further examined the measurement invariance property of the ISI across samples from different countries. Our analyses included one data set collected from a Taiwanese sample and two data sets obtained from samples in Hong Kong and Canada. The data set collected in Taiwan was analyzed with ordinal exploratory factor analysis (EFA) to obtain the appropriate factor model for the ISI. After that, we conducted a series of confirmatory factor analyses (CFAs), which is a special case of the structural equation model (SEM) that concerns the parameters in the measurement model, to the statistics collected in Canada and Hong Kong. The purposes of these CFA were to cross-validate the result obtained from EFA and further examine the cross-cultural measurement invariance of the ISI. The three-factor model outperforms other models in terms of global fit indices in Taiwan's population. Its external validity is also supported by confirmatory factor analyses. Furthermore, the measurement invariance analyses show that the strong invariance property between the samples from different cultures holds, providing evidence that the ISI results obtained in different cultures are comparable. The factorial validity of the ISI is stable in different populations. More importantly, its invariance property across cultures suggests that the ISI is a valid measure of the insomnia severity construct across countries. Copyright © 2014 Elsevier B.V. All rights reserved.
Sierakowska, Matylda; Sierakowski, Stanisław; Sierakowska, Justyna; Horton, Mike; Ndosi, Mwidimi
2015-03-01
To undertake cross-cultural adaptation and validation of the educational needs assessment tool (ENAT) for use with people with rheumatoid arthritis (RA) and systemic sclerosis (SSc) in Poland. The study involved two main phases: (1) cross-cultural adaptation of the ENAT from English into Polish and (2) Cross-cultural validation of Polish Educational Needs Assessment Tool (Pol-ENAT). The first phase followed an established process of cross-cultural adaptation of self-report measures. The second phase involved completion of the Pol-ENAT by patients and subjecting the data to Rasch analysis to assess the construct validity, unidimensionality, internal consistency and cross-cultural invariance. An adequate conceptual equivalence was achieved following the adaptation process. The dataset for validation comprised a total of 278 patients, 237 (85.3 %) of which were female. In each disease group (145, RA and 133, SSc), the 7 domains of the Pol-ENAT were found to fit the Rasch model, X (2)(df) = 16.953(14), p = 0.259 and 8.132(14), p = 0.882 for RA and SSc, respectively. Internal consistency of the Pol-ENAT was high (patient separation index = 0.85 and 0.89 for SSc and RA, respectively), and unidimensionality was confirmed. Cross-cultural differential item functioning (DIF) was detected in some subscales, and DIF-adjusted conversion tables were calibrated to enable cross-cultural comparison of data between Poland and the UK. Using a standard process in cross-cultural adaptation, conceptual equivalence was achieved between the original (UK) ENAT and the adapted Pol-ENAT. Fit to the Rasch model, confirmed that the construct validity, unidimensionality and internal consistency of the ENAT have been preserved.
Methods to compute reliabilities for genomic predictions of feed intake
USDA-ARS?s Scientific Manuscript database
For new traits without historical reference data, cross-validation is often the preferred method to validate reliability (REL). Time truncation is less useful because few animals gain substantial REL after the truncation point. Accurate cross-validation requires separating genomic gain from pedigree...
Experimental Errors in QSAR Modeling Sets: What We Can Do and What We Cannot Do.
Zhao, Linlin; Wang, Wenyi; Sedykh, Alexander; Zhu, Hao
2017-06-30
Numerous chemical data sets have become available for quantitative structure-activity relationship (QSAR) modeling studies. However, the quality of different data sources may be different based on the nature of experimental protocols. Therefore, potential experimental errors in the modeling sets may lead to the development of poor QSAR models and further affect the predictions of new compounds. In this study, we explored the relationship between the ratio of questionable data in the modeling sets, which was obtained by simulating experimental errors, and the QSAR modeling performance. To this end, we used eight data sets (four continuous endpoints and four categorical endpoints) that have been extensively curated both in-house and by our collaborators to create over 1800 various QSAR models. Each data set was duplicated to create several new modeling sets with different ratios of simulated experimental errors (i.e., randomizing the activities of part of the compounds) in the modeling process. A fivefold cross-validation process was used to evaluate the modeling performance, which deteriorates when the ratio of experimental errors increases. All of the resulting models were also used to predict external sets of new compounds, which were excluded at the beginning of the modeling process. The modeling results showed that the compounds with relatively large prediction errors in cross-validation processes are likely to be those with simulated experimental errors. However, after removing a certain number of compounds with large prediction errors in the cross-validation process, the external predictions of new compounds did not show improvement. Our conclusion is that the QSAR predictions, especially consensus predictions, can identify compounds with potential experimental errors. But removing those compounds by the cross-validation procedure is not a reasonable means to improve model predictivity due to overfitting.
Experimental Errors in QSAR Modeling Sets: What We Can Do and What We Cannot Do
2017-01-01
Numerous chemical data sets have become available for quantitative structure–activity relationship (QSAR) modeling studies. However, the quality of different data sources may be different based on the nature of experimental protocols. Therefore, potential experimental errors in the modeling sets may lead to the development of poor QSAR models and further affect the predictions of new compounds. In this study, we explored the relationship between the ratio of questionable data in the modeling sets, which was obtained by simulating experimental errors, and the QSAR modeling performance. To this end, we used eight data sets (four continuous endpoints and four categorical endpoints) that have been extensively curated both in-house and by our collaborators to create over 1800 various QSAR models. Each data set was duplicated to create several new modeling sets with different ratios of simulated experimental errors (i.e., randomizing the activities of part of the compounds) in the modeling process. A fivefold cross-validation process was used to evaluate the modeling performance, which deteriorates when the ratio of experimental errors increases. All of the resulting models were also used to predict external sets of new compounds, which were excluded at the beginning of the modeling process. The modeling results showed that the compounds with relatively large prediction errors in cross-validation processes are likely to be those with simulated experimental errors. However, after removing a certain number of compounds with large prediction errors in the cross-validation process, the external predictions of new compounds did not show improvement. Our conclusion is that the QSAR predictions, especially consensus predictions, can identify compounds with potential experimental errors. But removing those compounds by the cross-validation procedure is not a reasonable means to improve model predictivity due to overfitting. PMID:28691113
Alternative methods to evaluate trial level surrogacy.
Abrahantes, Josè Cortiñas; Shkedy, Ziv; Molenberghs, Geert
2008-01-01
The evaluation and validation of surrogate endpoints have been extensively studied in the last decade. Prentice [1] and Freedman, Graubard and Schatzkin [2] laid the foundations for the evaluation of surrogate endpoints in randomized clinical trials. Later, Buyse et al. [5] proposed a meta-analytic methodology, producing different methods for different settings, which was further studied by Alonso and Molenberghs [9], in their unifying approach based on information theory. In this article, we focus our attention on the trial-level surrogacy and propose alternative procedures to evaluate such surrogacy measure, which do not pre-specify the type of association. A promising correction based on cross-validation is investigated. As well as the construction of confidence intervals for this measure. In order to avoid making assumption about the type of relationship between the treatment effects and its distribution, a collection of alternative methods, based on regression trees, bagging, random forests, and support vector machines, combined with bootstrap-based confidence interval and, should one wish, in conjunction with a cross-validation based correction, will be proposed and applied. We apply the various strategies to data from three clinical studies: in opthalmology, in advanced colorectal cancer, and in schizophrenia. The results obtained for the three case studies are compared; they indicate that using random forest or bagging models produces larger estimated values for the surrogacy measure, which are in general stabler and the confidence interval narrower than linear regression and support vector regression. For the advanced colorectal cancer studies, we even found the trial-level surrogacy is considerably different from what has been reported. In general the alternative methods are more computationally demanding, and specially the calculation of the confidence intervals, require more computational time that the delta-method counterpart. First, more flexible modeling techniques can be used, allowing for other type of association. Second, when no cross-validation-based correction is applied, overly optimistic trial-level surrogacy estimates will be found, thus cross-validation is highly recommendable. Third, the use of the delta method to calculate confidence intervals is not recommendable since it makes assumptions valid only in very large samples. It may also produce range-violating limits. We therefore recommend alternatives: bootstrap methods in general. Also, the information-theoretic approach produces comparable results with the bagging and random forest approaches, when cross-validation correction is applied. It is also important to observe that, even for the case in which the linear model might be a good option too, bagging methods perform well too, and their confidence intervals were more narrow.
Küçükdeveci, Ayse A; Sahin, Hülya; Ataman, Sebnem; Griffiths, Bridget; Tennant, Alan
2004-02-15
Guidelines have been established for cross-cultural adaptation of outcome measures. However, invariance across cultures must also be demonstrated through analysis of Differential Item Functioning (DIF). This is tested in the context of a Turkish adaptation of the Health Assessment Questionnaire (HAQ). Internal construct validity of the adapted HAQ is assessed by Rasch analysis; reliability, by internal consistency and the intraclass correlation coefficient; external construct validity, by association with impairments and American College of Rheumatology functional stages. Cross-cultural validity is tested through DIF by comparison with data from the UK version of the HAQ. The adapted version of the HAQ demonstrated good internal construct validity through fit of the data to the Rasch model (mean item fit 0.205; SD 0.998). Reliability was excellent (alpha = 0.97) and external construct validity was confirmed by expected associations. DIF for culture was found in only 1 item. Cross-cultural validity was found to be sufficient for use in international studies between the UK and Turkey. Future adaptation of instruments should include analysis of DIF at the field testing stage in the adaptation process.
Validity Evidence for the Organizational Commitment Questionnaire in the Japanese Corporate Culture.
ERIC Educational Resources Information Center
White, Marion M.; And Others
1995-01-01
The validity of the Organizational Commitment Questionnaire as a measure of organizational commitment in the Japanese culture was studied with 1,481 Japanese employees. The three-factor model was a better fit to the data than the one- or two-factor models. Results support the cross-cultural utility of the measure. (SLD)
Spanish Adaptation and Validation of the Family Quality of Life Survey
ERIC Educational Resources Information Center
Verdugo, M. A.; Cordoba, L.; Gomez, J.
2005-01-01
Background: Assessing the quality of life (QOL) for families that include a person with a disability have recently become a major emphasis in cross-cultural QOL studies. The present study examined the reliability and validity of the Family Quality of Life Survey (FQOL) on a Spanish sample. Method and Results: The sample comprised 385 families who…
The Cross Validation of the Attitudes toward Mainstreaming Scale (ATMS).
ERIC Educational Resources Information Center
Berryman, Joan D.; Neal, W. R. Jr.
1980-01-01
Reliability and factorial validity of the Attitudes Toward Mainstreaming Scale was supported in a cross-validation study with teachers. Three factors emerged: learning capability, general mainstreaming, and traditional limiting disabilities. Factor intercorrelations varied from .42 to .55; correlations between total scores and individual factors…
Bernhard, Gerda; Knibbe, Ronald A; von Wolff, Alessa; Dingoyan, Demet; Schulz, Holger; Mösko, Mike
2015-01-01
Cultural competence of healthcare professionals (HCPs) is recognized as a strategy to reduce cultural disparities in healthcare. However, standardised, valid and reliable instruments to assess HCPs' cultural competence are notably lacking. The present study aims to 1) identify the core components of cultural competence from a healthcare perspective, 2) to develop a self-report instrument to assess cultural competence of HCPs and 3) to evaluate the psychometric properties of the new instrument. The conceptual model and initial item pool, which were applied to the cross-cultural competence instrument for the healthcare profession (CCCHP), were derived from an expert survey (n = 23), interviews with HCPs (n = 12), and a broad narrative review on assessment instruments and conceptual models of cultural competence. The item pool was reduced systematically, which resulted in a 59-item instrument. A sample of 336 psychologists, in advanced psychotherapeutic training, and 409 medical students participated, in order to evaluate the construct validity and reliability of the CCCHP. Construct validity was supported by principal component analysis, which led to a 32-item six-component solution with 50% of the total variance explained. The different dimensions of HCPs' cultural competence are: Cross-Cultural Motivation/Curiosity, Cross-Cultural Attitudes, Cross-Cultural Skills, Cross-Cultural Knowledge/Awareness and Cross-Cultural Emotions/Empathy. For the total instrument, the internal consistency reliability was .87 and the dimension's Cronbach's α ranged from .54 to .84. The discriminating power of the CCCHP was indicated by statistically significant mean differences in CCCHP subscale scores between predefined groups. The 32-item CCCHP exhibits acceptable psychometric properties, particularly content and construct validity to examine HCPs' cultural competence. The CCCHP with its five dimensions offers a comprehensive assessment of HCPs' cultural competence, and has the ability to distinguish between groups that are expected to differ in cultural competence. This instrument can foster professional development through systematic self-assessment and thus contributes to improve the quality of patient care.
Gupta, Meenal; Moily, Nagaraj S; Kaur, Harpreet; Jajodia, Ajay; Jain, Sanjeev; Kukreti, Ritushree
2013-08-01
Atypical antipsychotic (AAP) drugs are the preferred choice of treatment for schizophrenia patients. Patients who do not show favorable response to AAP monotherapy are subjected to random prolonged therapeutic treatment with AAP multitherapy, typical antipsychotics or a combination of both. Therefore, prior identification of patients' response to drugs can be an important step in providing efficacious and safe therapeutic treatment. We thus attempted to elucidate a genetic signature which could predict patients' response to AAP monotherapy. Our logistic regression analyses indicated the probability that 76% patients carrying combination of four SNPs will not show favorable response to AAP therapy. The robustness of this prediction model was assessed using repeated 10-fold cross validation method, and the results across n-fold cross-validations (mean accuracy=71.91%; 95%CI=71.47-72.35) suggest high accuracy and reliability of the prediction model. Further validations of these results in large sample sets are likely to establish their clinical applicability. Copyright © 2013 Elsevier Inc. All rights reserved.
Validation of the WIMSD4M cross-section generation code with benchmark results
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deen, J.R.; Woodruff, W.L.; Leal, L.E.
1995-01-01
The WIMSD4 code has been adopted for cross-section generation in support of the Reduced Enrichment Research and Test Reactor (RERTR) program at Argonne National Laboratory (ANL). Subsequently, the code has undergone several updates, and significant improvements have been achieved. The capability of generating group-collapsed micro- or macroscopic cross sections from the ENDF/B-V library and the more recent evaluation, ENDF/B-VI, in the ISOTXS format makes the modified version of the WIMSD4 code, WIMSD4M, very attractive, not only for the RERTR program, but also for the reactor physics community. The intent of the present paper is to validate the WIMSD4M cross-section librariesmore » for reactor modeling of fresh water moderated cores. The results of calculations performed with multigroup cross-section data generated with the WIMSD4M code will be compared against experimental results. These results correspond to calculations carried out with thermal reactor benchmarks of the Oak Ridge National Laboratory (ORNL) unreflected HEU critical spheres, the TRX LEU critical experiments, and calculations of a modified Los Alamos HEU D{sub 2}O moderated benchmark critical system. The benchmark calculations were performed with the discrete-ordinates transport code, TWODANT, using WIMSD4M cross-section data. Transport calculations using the XSDRNPM module of the SCALE code system are also included. In addition to transport calculations, diffusion calculations with the DIF3D code were also carried out, since the DIF3D code is used in the RERTR program for reactor analysis and design. For completeness, Monte Carlo results of calculations performed with the VIM and MCNP codes are also presented.« less
Validation of the WIMSD4M cross-section generation code with benchmark results
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leal, L.C.; Deen, J.R.; Woodruff, W.L.
1995-02-01
The WIMSD4 code has been adopted for cross-section generation in support of the Reduced Enrichment for Research and Test (RERTR) program at Argonne National Laboratory (ANL). Subsequently, the code has undergone several updates, and significant improvements have been achieved. The capability of generating group-collapsed micro- or macroscopic cross sections from the ENDF/B-V library and the more recent evaluation, ENDF/B-VI, in the ISOTXS format makes the modified version of the WIMSD4 code, WIMSD4M, very attractive, not only for the RERTR program, but also for the reactor physics community. The intent of the present paper is to validate the procedure to generatemore » cross-section libraries for reactor analyses and calculations utilizing the WIMSD4M code. To do so, the results of calculations performed with group cross-section data generated with the WIMSD4M code will be compared against experimental results. These results correspond to calculations carried out with thermal reactor benchmarks of the Oak Ridge National Laboratory(ORNL) unreflected critical spheres, the TRX critical experiments, and calculations of a modified Los Alamos highly-enriched heavy-water moderated benchmark critical system. The benchmark calculations were performed with the discrete-ordinates transport code, TWODANT, using WIMSD4M cross-section data. Transport calculations using the XSDRNPM module of the SCALE code system are also included. In addition to transport calculations, diffusion calculations with the DIF3D code were also carried out, since the DIF3D code is used in the RERTR program for reactor analysis and design. For completeness, Monte Carlo results of calculations performed with the VIM and MCNP codes are also presented.« less
Exact Analysis of Squared Cross-Validity Coefficient in Predictive Regression Models
ERIC Educational Resources Information Center
Shieh, Gwowen
2009-01-01
In regression analysis, the notion of population validity is of theoretical interest for describing the usefulness of the underlying regression model, whereas the presumably more important concept of population cross-validity represents the predictive effectiveness for the regression equation in future research. It appears that the inference…
Rodrigues, Marcelo F; Michel-Crosato, Edgard; Cardoso, Jefferson R; Traebert, Jefferson
2009-06-01
Cross-cultural translation and psychometric testing. To translate and cross-culturally adapt the Quebec Back Pain Disability Scale (QDS) to Brazilian Portuguese and to examine its validity and reliability. Current literature shows the need to adopt reliable and internationally standardized methods for the analysis of low back pain. To our knowledge, this specific questionnaire has not been translated and validated for Portuguese-speaking patients. The translation and cross-cultural adaptation of the QDS were developed in agreement with internationally recommended methodology, and the resulting product was evaluated in this study with 54 consecutive patients. Internal consistency was obtained through Cronbach's alpha; reliability was estimated through the intraclass correlation coefficient and the Bland and Altman agreement (d = mean difference). Validity was determined by correlating the scores of the Brazil-QDS with the Brazilian version of the Roland-Morris Questionnaire and Visual Analogue Pain Scale by means of the Spearman rank correlation coefficient. The internal consistency obtained was excellent (Cronbach's alpha = 0.97). Intraobserver and interobserver reliability were considered strong (ICC = 0.93-d = 0.68 and 0.96-d = 0.57, respectively). The correlation with Brazilian Roland-Morris Questionnaire and with the Visual Analogue Scale was high (r = 0.857; r = 0.758, respectively). The data showed that the process of translation and cross-cultural adaptation were successful and that the adapted instrument demonstrated excellent psychometric properties.
Landscape scale estimation of soil carbon stock using 3D modelling.
Veronesi, F; Corstanje, R; Mayr, T
2014-07-15
Soil C is the largest pool of carbon in the terrestrial biosphere, and yet the processes of C accumulation, transformation and loss are poorly accounted for. This, in part, is due to the fact that soil C is not uniformly distributed through the soil depth profile and most current landscape level predictions of C do not adequately account the vertical distribution of soil C. In this study, we apply a method based on simple soil specific depth functions to map the soil C stock in three-dimensions at landscape scale. We used soil C and bulk density data from the Soil Survey for England and Wales to map an area in the West Midlands region of approximately 13,948 km(2). We applied a method which describes the variation through the soil profile and interpolates this across the landscape using well established soil drivers such as relief, land cover and geology. The results indicate that this mapping method can effectively reproduce the observed variation in the soil profiles samples. The mapping results were validated using cross validation and an independent validation. The cross-validation resulted in an R(2) of 36% for soil C and 44% for BULKD. These results are generally in line with previous validated studies. In addition, an independent validation was undertaken, comparing the predictions against the National Soil Inventory (NSI) dataset. The majority of the residuals of this validation are between ± 5% of soil C. This indicates high level of accuracy in replicating topsoil values. In addition, the results were compared to a previous study estimating the carbon stock of the UK. We discuss the implications of our results within the context of soil C loss factors such as erosion and the impact on regional C process models. Copyright © 2014 Elsevier B.V. All rights reserved.
Turner, Nigel E; Elton-Marshall, Tara; Shi, Jing; Wiebe, Jamie; Boak, Angela; van der Maas, Mark; Mann, Robert E
2018-06-01
This paper reports on the cross validation of the Gambling Problem Severity Subscale of the Canadian Adolescent Gambling Index (CAGI/GPSS). The CAGI/GPSS was included in a large school based drug use and health survey conducted in 2015. Data from students in grades 9-12 (ages 13-20 years) derived from the (N = 3369 students). The CAGI/GPSS produced an alpha of 0.789. A principle component analysis revealed two eigenvalues greater than one. An oblique rotation revealed these components to represent consequences and over involvement. The CAGI/GPSS indicated that 1% of the students fell into the "red" category indicating a severe problem and an additional 3.3% scored in the "yellow" category indicating low to moderate problems. The CAGI/GPSS was shown to be significantly correlated with gambling frequency (r = 0.36), largest expenditure (r = 0.37), sex (more likely to be male) (r = -0.19), lower school marks (r = -0.07), hazardous drinking, (r = 0.16), problem video game play (r = 0.16), as well as substance abuse. The CAGI/GPSS was cross validated using a shorted version of the short SOGS, r = 0.48. In addition the CAGI/GPSS and short SOGS produced very similar patterns of correlations results. The results support the validity and reliability of the CAGI/GPSS as a measure of gambling problems among adolescents.
Simulation of SEU Cross-sections using MRED under Conditions of Limited Device Information
NASA Technical Reports Server (NTRS)
Lauenstein, J. M.; Reed, R. A.; Weller, R. A.; Mendenhall, M. H.; Warren, K. M.; Pellish, J. A.; Schrimpf, R. D.; Sierawski, B. D.; Massengill, L. W.; Dodd, P. E.;
2007-01-01
This viewgraph presentation reviews the simulation of Single Event Upset (SEU) cross sections using the membrane electrode assembly (MEA) resistance and electrode diffusion (MRED) tool using "Best guess" assumptions about the process and geometry, and direct ionization, low-energy beam test results. This work will also simulate SEU cross-sections including angular and high energy responses and compare the simulated results with beam test data for the validation of the model. Using MRED, we produced a reasonably accurate upset response model of a low-critical charge SRAM without detailed information about the circuit, device geometry, or fabrication process
Comparing ordinary kriging and inverse distance weighting for soil as pollution in Beijing.
Qiao, Pengwei; Lei, Mei; Yang, Sucai; Yang, Jun; Guo, Guanghui; Zhou, Xiaoyong
2018-06-01
Spatial interpolation method is the basis of soil heavy metal pollution assessment and remediation. The existing evaluation index for interpolation accuracy did not combine with actual situation. The selection of interpolation methods needs to be based on specific research purposes and research object characteristics. In this paper, As pollution in soils of Beijing was taken as an example. The prediction accuracy of ordinary kriging (OK) and inverse distance weighted (IDW) were evaluated based on the cross validation results and spatial distribution characteristics of influencing factors. The results showed that, under the condition of specific spatial correlation, the cross validation results of OK and IDW for every soil point and the prediction accuracy of spatial distribution trend are similar. But the prediction accuracy of OK for the maximum and minimum is less than IDW, while the number of high pollution areas identified by OK are less than IDW. It is difficult to identify the high pollution areas fully by OK, which shows that the smoothing effect of OK is obvious. In addition, with increasing of the spatial correlation of As concentration, the cross validation error of OK and IDW decreases, and the high pollution area identified by OK is approaching the result of IDW, which can identify the high pollution areas more comprehensively. However, because the semivariogram constructed by OK interpolation method is more subjective and requires larger number of soil samples, IDW is more suitable for spatial prediction of heavy metal pollution in soils.
Reduction of bias and variance for evaluation of computer-aided diagnostic schemes.
Li, Qiang; Doi, Kunio
2006-04-01
Computer-aided diagnostic (CAD) schemes have been developed to assist radiologists in detecting various lesions in medical images. In addition to the development, an equally important problem is the reliable evaluation of the performance levels of various CAD schemes. It is good to see that more and more investigators are employing more reliable evaluation methods such as leave-one-out and cross validation, instead of less reliable methods such as resubstitution, for assessing their CAD schemes. However, the common applications of leave-one-out and cross-validation evaluation methods do not necessarily imply that the estimated performance levels are accurate and precise. Pitfalls often occur in the use of leave-one-out and cross-validation evaluation methods, and they lead to unreliable estimation of performance levels. In this study, we first identified a number of typical pitfalls for the evaluation of CAD schemes, and conducted a Monte Carlo simulation experiment for each of the pitfalls to demonstrate quantitatively the extent of bias and/or variance caused by the pitfall. Our experimental results indicate that considerable bias and variance may exist in the estimated performance levels of CAD schemes if one employs various flawed leave-one-out and cross-validation evaluation methods. In addition, for promoting and utilizing a high standard for reliable evaluation of CAD schemes, we attempt to make recommendations, whenever possible, for overcoming these pitfalls. We believe that, with the recommended evaluation methods, we can considerably reduce the bias and variance in the estimated performance levels of CAD schemes.
Cross-cultural validity of four quality of life scales in persons with spinal cord injury
2010-01-01
Background Quality of life (QoL) in persons with spinal cord injury (SCI) has been found to differ across countries. However, comparability of measurement results between countries depends on the cross-cultural validity of the applied instruments. The study examined the metric quality and cross-cultural validity of the Satisfaction with Life Scale (SWLS), the Life Satisfaction Questionnaire (LISAT-9), the Personal Well-Being Index (PWI) and the 5-item World Health Organization Quality of Life Assessment (WHOQoL-5) across six countries in a sample of persons with spinal cord injury (SCI). Methods A cross-sectional multi-centre study was conducted and the data of 243 out-patients with SCI from study centers in Australia, Brazil, Canada, Israel, South Africa, and the United States were analyzed using Rasch-based methods. Results The analyses showed high reliability for all 4 instruments (person reliability index .78-.92). Unidimensionality of measurement was supported for the WHOQoL-5 (Chi2 = 16.43, df = 10, p = .088), partially supported for the PWI (Chi2 = 15.62, df = 16, p = .480), but rejected for the LISAT-9 (Chi2 = 50.60, df = 18, p = .000) and the SWLS (Chi2 = 78.54, df = 10, p = .000) based on overall and item-wise Chi2 tests, principal components analyses and independent t-tests. The response scales showed the expected ordering for the WHOQoL-5 and the PWI, but not for the other two instruments. Using differential item functioning (DIF) analyses potential cross-country bias was found in two items of the SWLS and the WHOQoL-5, three items of the LISAT-9 and four items of the PWI. However, applying Rasch-based statistical methods, especially subtest analyses, it was possible to identify optimal strategies to enhance the metric properties and the cross-country equivalence of the instruments post-hoc. Following the post-hoc procedures the WHOQOL-5 and the PWI worked in a consistent and expected way in all countries. Conclusions QoL assessment using the summary scores of the WHOQOL-5 and the PWI appeared cross-culturally valid in persons with SCI. In contrast, summary scores of the LISAT-9 and the SWLS have to be interpreted with caution. The findings of the current study can be especially helpful to select instruments for international research projects in SCI. PMID:20815864
Tomaschewski-Barlem, Jamila Geri; Lunardi, Valéria Lerch; Barlem, Edison Luiz Devos; da Silveira, Rosemary Silva; Dalmolin, Graziele de Lima; Ramos, Aline Marcelino
2015-01-01
Abstract Objective: to adapt culturally and validate the Protective Nursing Advocacy Scale for Brazilian nurses. Method: methodological study carried out with 153 nurses from two hospitals in the South region of Brazil, one public and the other philanthropic. The cross-cultural adaptation of the Protective Nursing Advocacy Scale was performed according to international standards, and its validation was carried out for use in the Brazilian context, by means of factor analysis and Cronbach's alpha as measure of internal consistency. Results: by means of evaluation by a committee of experts and application of pre-test, face validity and content validity of the instrument were considered satisfactory. From the factor analysis, five constructs were identified: negative implications of the advocacy practice, advocacy actions, facilitators of the advocacy practice, perceptions that favor practice advocacy and barriers to advocacy practice. The instrument showed satisfactory internal consistency, with Cronbach's alpha values ranging from 0.70 to 0.87. Conclusion: it was concluded that the Protective Nursing Advocacy Scale - Brazilian version, is a valid and reliable instrument for use in the evaluation of beliefs and actions of health advocacy, performed by Brazilian nurses in their professional practice environment. PMID:26444169
2D-QSAR and 3D-QSAR Analyses for EGFR Inhibitors
Zhao, Manman; Zheng, Linfeng; Qiu, Chun
2017-01-01
Epidermal growth factor receptor (EGFR) is an important target for cancer therapy. In this study, EGFR inhibitors were investigated to build a two-dimensional quantitative structure-activity relationship (2D-QSAR) model and a three-dimensional quantitative structure-activity relationship (3D-QSAR) model. In the 2D-QSAR model, the support vector machine (SVM) classifier combined with the feature selection method was applied to predict whether a compound was an EGFR inhibitor. As a result, the prediction accuracy of the 2D-QSAR model was 98.99% by using tenfold cross-validation test and 97.67% by using independent set test. Then, in the 3D-QSAR model, the model with q2 = 0.565 (cross-validated correlation coefficient) and r2 = 0.888 (non-cross-validated correlation coefficient) was built to predict the activity of EGFR inhibitors. The mean absolute error (MAE) of the training set and test set was 0.308 log units and 0.526 log units, respectively. In addition, molecular docking was also employed to investigate the interaction between EGFR inhibitors and EGFR. PMID:28630865
Facial disability index (FDI): Adaptation to Spanish, reliability and validity
Gonzalez-Cardero, Eduardo; Cayuela, Aurelio; Acosta-Feria, Manuel; Gutierrez-Perez, Jose-Luis
2012-01-01
Objectives: To adapt to Spanish the facial disability index (FDI) described by VanSwearingen and Brach in 1995 and to assess its reliability and validity in patients with facial nerve paresis after parotidectomy. Study Design: The present study was conducted in two different stages: a) cross-cultural adaptation of the questionnaire and b) cross-sectional study of a control group of 79 Spanish-speaking patients who suffered facial paresis after superficial parotidectomy with facial nerve preservation. The cross-cultural adaptation process comprised the following stages: (I) initial translation, (II) synthesis of the translated document, (III) retro-translation, (IV) review by a board of experts, (V) pilot study of the pre-final draft and (VI) analysis of the pilot study and final draft. Results: The reliability and internal consistency of every one of the rating scales included in the FDI (Cronbach’s alpha coefficient) was 0.83 for the complete scale and 0.77 and 0.82 for the physical and the social well-being subscales. The analysis of the factorial validity of the main components of the adapted FDI yielded similar results to the original questionnaire. Bivariate correlations between FDI and House-Brackmann scale were positive. The variance percentage was calculated for all FDI components. Conclusions: The FDI questionnaire is a specific instrument for assessing facial neuromuscular dysfunction which becomes a useful tool in order to determine quality of life in patients with facial nerve paralysis. Spanish adapted FDI is equivalent to the original questionnaire and shows similar reliability and validity. The proven reproducibi-lity, reliability and validity of this questionnaire make it a useful additional tool for evaluating the impact of facial nerve paralysis in Spanish-speaking patients. Key words:Parotidectomy, facial nerve paralysis, facial disability. PMID:22926474
Koritar, Priscila; Philippi, Sonia Tucunduva; Alvarenga, Marle dos Santos; Santos, Bernardo dos
2014-08-01
The scope of this study was to show the cross-cultural adaptation and validation of the Health and Taste Attitude Scale in Portuguese. The methodology included translation of the scale; evaluation of conceptual, operational and item-based equivalence by 14 experts and 51 female undergraduates; semantic equivalence and measurement assessment by 12 bilingual women by the paired t-test, the Pearson correlation coefficient and the coefficient intraclass correlation; internal consistency and test-retest reliability by Cronbach's alpha and intraclass correlation coefficient, respectively, after application on 216 female undergraduates; assessment of discriminant and concurrent validity via the t-test and Spearman's correlation coefficient, respectively, in addition to Confirmatory Factor and Exploratory Factor Analysis. The scale was considered adequate and easily understood by the experts and university students and presented good internal consistency and reliability (µ 0.86, ICC 0.84). The results show that the scale is valid and can be used in studies with women to better understand attitudes related to taste.
Kim, SungHwan; Lin, Chien-Wei; Tseng, George C
2016-07-01
Supervised machine learning is widely applied to transcriptomic data to predict disease diagnosis, prognosis or survival. Robust and interpretable classifiers with high accuracy are usually favored for their clinical and translational potential. The top scoring pair (TSP) algorithm is an example that applies a simple rank-based algorithm to identify rank-altered gene pairs for classifier construction. Although many classification methods perform well in cross-validation of single expression profile, the performance usually greatly reduces in cross-study validation (i.e. the prediction model is established in the training study and applied to an independent test study) for all machine learning methods, including TSP. The failure of cross-study validation has largely diminished the potential translational and clinical values of the models. The purpose of this article is to develop a meta-analytic top scoring pair (MetaKTSP) framework that combines multiple transcriptomic studies and generates a robust prediction model applicable to independent test studies. We proposed two frameworks, by averaging TSP scores or by combining P-values from individual studies, to select the top gene pairs for model construction. We applied the proposed methods in simulated data sets and three large-scale real applications in breast cancer, idiopathic pulmonary fibrosis and pan-cancer methylation. The result showed superior performance of cross-study validation accuracy and biomarker selection for the new meta-analytic framework. In conclusion, combining multiple omics data sets in the public domain increases robustness and accuracy of the classification model that will ultimately improve disease understanding and clinical treatment decisions to benefit patients. An R package MetaKTSP is available online. (http://tsenglab.biostat.pitt.edu/software.htm). ctseng@pitt.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Viability of Cross-Flow Fan with Helical Blades for Vertical Take-off and Landing Aircraft
2012-09-01
fluid dynamics (CFD) software, ANSYS - CFX , a three-dimensional (3-D) straight-bladed model was validated against previous study’s experimental results...computational fluid dynamics software (CFD), ANSYS - CFX , a three-dimensional (3-D) straight-bladed model was validated against previous study’s experimental...37 B. SIZING PARAMETERS AND ILLUSTRATION ................................. 37 APPENDIX B. ANSYS CFX PARAMETERS
A Cross-Validation of the Keane and Penk MMPI Scales as Measures of Post-Traumatic Stress Disorder.
ERIC Educational Resources Information Center
Watson, Charles G.; And Others
1986-01-01
Compared scores of post-traumatic stress disorder (PTSD) patients, psychiatric patients who did not meet PTSD criteria, and normals on the Keane et al PTSD scale and Penk Combat Scales for the Minnesota Multiphasic Personality Inventory. Results confirmed the validities of the PTSO scale and, to a lesser degree, Penk Combat Intensity Scales as…
ERIC Educational Resources Information Center
Lombardi, Allison; Seburn, Mary; Conley, David
2011-01-01
In this cross-validation study, the authors examined the psychometric properties of a measure of academic behaviors associated with college and career readiness intended for high school students. An exploratory factor analysis (EFA) was conducted with a randomly selected portion of the sample (n = 413) and resulted in four reliable factors:…
Reliable Digit Span: A Systematic Review and Cross-Validation Study
ERIC Educational Resources Information Center
Schroeder, Ryan W.; Twumasi-Ankrah, Philip; Baade, Lyle E.; Marshall, Paul S.
2012-01-01
Reliable Digit Span (RDS) is a heavily researched symptom validity test with a recent literature review yielding more than 20 studies ranging in dates from 1994 to 2011. Unfortunately, limitations within some of the research minimize clinical generalizability. This systematic review and cross-validation study was conducted to address these…
Reimers, Anne K; Jekauc, Darko; Mess, Filip; Mewes, Nadine; Woll, Alexander
2012-08-29
The purpose of this study was to examine the internal consistency, test-retest reliability, construct validity and predictive validity of a new German self-report instrument to assess the influence of social support and the physical environment on physical activity in adolescents. Based on theoretical consideration, the short scales on social support and physical environment were developed and cross-validated in two independent study samples of 9 to 17 year-old girls and boys. The longitudinal sample of Study I (n = 196) was recruited from a German comprehensive school, and subjects in this study completed the questionnaire twice with a between-test interval of seven days. Cronbach's alphas were computed to determine the internal consistency of the factors. Test-retest reliability of the latent factors was assessed using intra-class coefficients. Factorial validity of the scales was assessed using principle components analysis. Construct validity was determined using a cross-validation technique by performing confirmatory factor analysis with the independent nationwide cross-sectional sample of Study II (n = 430). Correlations between factors and three measures of physical activity (objectively measured moderate-to-vigorous physical activity (MVPA), self-reported habitual MVPA and self-reported recent MVPA) were calculated to determine the predictive validity of the instrument. Construct validity of the social support scale (two factors: parental support and peer support) and the physical environment scale (four factors: convenience, public recreation facilities, safety and private sport providers) was shown. Both scales had moderate test-retest reliability. The factors of the social support scale also had good internal consistency and predictive validity. Internal consistency and predictive validity of the physical environment scale were low to acceptable. The results of this study indicate moderate to good reliability and construct validity of the social support scale and physical environment scale. Predictive validity was only confirmed for the social support scale but not for the physical environment scale. Hence, it remains unclear if a person's physical environment has a direct or an indirect effect on physical activity behavior or a moderation function.
Bias correction for selecting the minimal-error classifier from many machine learning models.
Ding, Ying; Tang, Shaowu; Liao, Serena G; Jia, Jia; Oesterreich, Steffi; Lin, Yan; Tseng, George C
2014-11-15
Supervised machine learning is commonly applied in genomic research to construct a classifier from the training data that is generalizable to predict independent testing data. When test datasets are not available, cross-validation is commonly used to estimate the error rate. Many machine learning methods are available, and it is well known that no universally best method exists in general. It has been a common practice to apply many machine learning methods and report the method that produces the smallest cross-validation error rate. Theoretically, such a procedure produces a selection bias. Consequently, many clinical studies with moderate sample sizes (e.g. n = 30-60) risk reporting a falsely small cross-validation error rate that could not be validated later in independent cohorts. In this article, we illustrated the probabilistic framework of the problem and explored the statistical and asymptotic properties. We proposed a new bias correction method based on learning curve fitting by inverse power law (IPL) and compared it with three existing methods: nested cross-validation, weighted mean correction and Tibshirani-Tibshirani procedure. All methods were compared in simulation datasets, five moderate size real datasets and two large breast cancer datasets. The result showed that IPL outperforms the other methods in bias correction with smaller variance, and it has an additional advantage to extrapolate error estimates for larger sample sizes, a practical feature to recommend whether more samples should be recruited to improve the classifier and accuracy. An R package 'MLbias' and all source files are publicly available. tsenglab.biostat.pitt.edu/software.htm. ctseng@pitt.edu Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Coster, Wendy J.; Haley, Stephen M.; Ni, Pengsheng; Dumas, Helene M.; Fragala-Pinkham, Maria A.
2009-01-01
Objective To examine score agreement, validity, precision, and response burden of a prototype computer adaptive testing (CAT) version of the Self-Care and Social Function scales of the Pediatric Evaluation of Disability Inventory (PEDI) compared to the full-length version of these scales. Design Computer simulation analysis of cross-sectional and longitudinal retrospective data; cross-sectional prospective study. Settings Pediatric rehabilitation hospital, including inpatient acute rehabilitation, day school program, outpatient clinics; community-based day care, preschool, and children’s homes. Participants Four hundred sixty-nine children with disabilities and 412 children with no disabilities (analytic sample); 38 children with disabilities and 35 children without disabilities (cross-validation sample). Interventions Not applicable. Main Outcome Measures Summary scores from prototype CAT applications of each scale using 15-, 10-, and 5-item stopping rules; scores from the full-length Self-Care and Social Function scales; time (in seconds) to complete assessments and respondent ratings of burden. Results Scores from both computer simulations and field administration of the prototype CATs were highly consistent with scores from full-length administration (all r’s between .94 and .99). Using computer simulation of retrospective data, discriminant validity and sensitivity to change of the CATs closely approximated that of the full-length scales, especially when the 15- and 10-item stopping rules were applied. In the cross-validation study the time to administer both CATs was 4 minutes, compared to over 16 minutes to complete the full-length scales. Conclusions Self-care and Social Function score estimates from CAT administration are highly comparable to those obtained from full-length scale administration, with small losses in validity and precision and substantial decreases in administration time. PMID:18373991
ERIC Educational Resources Information Center
Zhang, Xiaozhou; Tze, Virginia M. C.; Buhr, Erin; Klassen, Robert M.; Daniels, Lia M.
2016-01-01
The current study provided evidence for the factor structure of the Academic Expectation Stress Inventory (AESI) in a sample of 213 Mainland Chinese and 184 South Korean high school students. We examined cross-national invariance of the AESI using multiple-group confirmatory factor analysis across two Asian cultural samples. Results suggested a…
Validity Issues Involved in Cross-Grade Statements about NAEP Results
ERIC Educational Resources Information Center
Thissen, David
2012-01-01
The reading and mathematics measures of the National Assessment of Educational Progress (NAEP) have been, and continue to be, reported on scales that appear to have the properties of "cross-grade" scales: Reported scores are higher for 8th-grade students than for 4th-grade students, and higher for 12th-grade students than for 8th-grade students.…
Arimura, Tatsuyuki; Hosoi, Masako; Tsukiyama, Yoshihiro; Yoshida, Toshiyuki; Fujiwara, Daiki; Tanaka, Masanori; Tamura, Ryuichi; Nakashima, Yasunori; Sudo, Nobuyuki; Kubo, Chiharu
2012-04-01
The present study aimed to develop a Japanese version of the Short-Form McGill Pain Questionnaire (SF-MPQ-J) that focuses on cross-culturally equivalence to the original English version and to test its reliability and validity. Cross-sectional design. In study 1, SF-MPQ was translated and adapted into Japanese. It included construction of response scales equivalent to the original using a variation of the Thurstone method of equal-appearing intervals. A total of 147 undergraduate students and 44 pain patients participated in the development of the Japanese response scales. To measure the equivalence of pain descriptors, 62 pain patients in four diagnostic groups were asked to choose pain descriptors that described their pain. In study 2, chronic pain patients (N=126) completed the SF-MPQ-J, the Long-Form McGill Pain Questionnaire Japanese version (LF-MPQ-J), and the 11-point numerical rating scale of pain intensity. Correlation analysis examined the construct validity of the SF-MPQ-J. The results from study 1 were used to develop SF-MPQ-J, which is linguistically equivalent to the original questionnaire. Response scales from SF-MPQ-J represented the original scale values. All pain descriptors, except one, were used by >33% in at least one of the four diagnostic groups. Study 2 exhibited adequate internal consistency and test-retest reliability, with the construct validity of SF-MPQ-J comparable to the original. These findings suggested that SF-MPQ-J is reliable, valid, and cross-culturally equivalent to the original questionnaire. Researchers might consider using this scale in multicenter, multi-ethnical trials or cross-cultural studies that include Japanese-speaking patients. Wiley Periodicals, Inc.
Choi, Bongsam
2018-01-01
[Purpose] This study aimed to cross-cultural adapt and validate the Korean version of an physical activity measure (K-PAM) for community-dwelling elderly. [Subjects and Methods] One hundred and thirty eight community-dwelling elderlies, 32 males and 106 female, participated in the study. All participants were asked to fill out a fifty-one item questionnaire measuring perceived difficulty in the activities of daily living (ADL) for the elderly. One-parameter model of item response theory (Rasch analysis) was applied to determine the construct validity and to inspect item-level psychometric properties of 51 ADL items of the K-PAM. [Results] Person separation reliability (analogous to Cronbach's alpha) for internal consistency was ranging 0.93 to 0.94. A total of 16 items was misfit to the Rasch model. After misfit item deletion, 35 ADL items of the K-PAM were placed in an empirically meaningful hierarchy from easy to hard. The item-person map analysis delineated that the item difficulty was well matched for the elderlies with moderate and low ability except for high ceilings. [Conclusion] Cross-cultural adapted K-PAM was shown to be sufficient for establishing construct validity and stable psychometric properties confirmed by person separation reliability and fit statistics.
Lohrer, H; Nauck, T
2010-06-01
The VISA-A questionnaire is currently the only valid, reliable, and disease specific patient administered questionnaire for research in Achilles tendinopathy. To perform multinational and multilingual investigations this instrument was already adapted to several languages. According to the "guidelines for the process of cross-cultural adaptation of self-report measures" we already translated and validated the VISA-A questionnaire for patients with Achilles tendinopathy. To cross-culturally adapt and validate the VISA-A Questionnaire for German-speaking patients suffering from Haglund's disease. The VISA-A-G questionnaire was tested for reliability, validity, and internal consistency in 39 Haglund's disease patients and 79 asymptomatic persons. For concurrent validity the VISA-A-G was compared with the Curwin and Stanish tendon grading system and with the Percy and Conochie classification system for the effect of pain on athletic performance. VISA-A-G results in Haglund's disease were additionally compared with VISA-A-G results obtained from Achilles tendinopathy patients and with VISA-A results presented in the international literature. ICC for the VISA-A-G questionnaire in conservatively treated Haglund's disease patients was 0.96. In asymptomatic students and joggers ICC was 0.97 and 0.60. When correlated with the grading system of Curwin and Stanish and with the Percy and Conochie classification rho was -0.95 and 0.94, respectively. Internal consistency (Cronbach's alpha) for the total VISA-A-G scores of the patients was calculated to be 0.87. Compared with VISA-A-G results obtained from Achilles tendinopathy patients there was no relevant difference discernible. Compared with VISA-A results presented in the original publication no difference was found statistically for students, healthy people, conservative, and preoperative patients, respectively. This study confirms that the VISA-A-G is a valid and reliable measure for German-speaking patients suffering from Haglund's disease. Georg Thieme Verlag KG Stuttgart, New York.
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.
Schleier, Jerome J.; Peterson, Robert K.D.; Irvine, Kathryn M.; Marshall, Lucy M.; Weaver, David K.; Preftakes, Collin J.
2012-01-01
One of the more effective ways of managing high densities of adult mosquitoes that vector human and animal pathogens is ultra-low-volume (ULV) aerosol applications of insecticides. The U.S. Environmental Protection Agency uses models that are not validated for ULV insecticide applications and exposure assumptions to perform their human and ecological risk assessments. Currently, there is no validated model that can accurately predict deposition of insecticides applied using ULV technology for adult mosquito management. In addition, little is known about the deposition and drift of small droplets like those used under conditions encountered during ULV applications. The objective of this study was to perform field studies to measure environmental concentrations of insecticides and to develop a validated model to predict the deposition of ULV insecticides. The final regression model was selected by minimizing the Bayesian Information Criterion and its prediction performance was evaluated using k-fold cross validation. Density of the formulation and the density and CMD interaction coefficients were the largest in the model. The results showed that as density of the formulation decreases, deposition increases. The interaction of density and CMD showed that higher density formulations and larger droplets resulted in greater deposition. These results are supported by the aerosol physics literature. A k-fold cross validation demonstrated that the mean square error of the selected regression model is not biased, and the mean square error and mean square prediction error indicated good predictive ability.
ERIC Educational Resources Information Center
Jordans, M. J. D.; Komproe, I. H.; Tol, W. A.; De Jong, J. T. V. M.
2009-01-01
Background: Large-scale psychosocial interventions in complex emergencies call for a screening procedure to identify individuals at risk. To date there are no screening instruments that are developed within low- and middle-income countries and validated for that purpose. The present study assesses the cross-cultural validity of the brief,…
NASA Astrophysics Data System (ADS)
Folkert, Michael R.; Setton, Jeremy; Apte, Aditya P.; Grkovski, Milan; Young, Robert J.; Schöder, Heiko; Thorstad, Wade L.; Lee, Nancy Y.; Deasy, Joseph O.; Oh, Jung Hun
2017-07-01
In this study, we investigate the use of imaging feature-based outcomes research (‘radiomics’) combined with machine learning techniques to develop robust predictive models for the risk of all-cause mortality (ACM), local failure (LF), and distant metastasis (DM) following definitive chemoradiation therapy (CRT). One hundred seventy four patients with stage III-IV oropharyngeal cancer (OC) treated at our institution with CRT with retrievable pre- and post-treatment 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) scans were identified. From pre-treatment PET scans, 24 representative imaging features of FDG-avid disease regions were extracted. Using machine learning-based feature selection methods, multiparameter logistic regression models were built incorporating clinical factors and imaging features. All model building methods were tested by cross validation to avoid overfitting, and final outcome models were validated on an independent dataset from a collaborating institution. Multiparameter models were statistically significant on 5 fold cross validation with the area under the receiver operating characteristic curve (AUC) = 0.65 (p = 0.004), 0.73 (p = 0.026), and 0.66 (p = 0.015) for ACM, LF, and DM, respectively. The model for LF retained significance on the independent validation cohort with AUC = 0.68 (p = 0.029) whereas the models for ACM and DM did not reach statistical significance, but resulted in comparable predictive power to the 5 fold cross validation with AUC = 0.60 (p = 0.092) and 0.65 (p = 0.062), respectively. In the largest study of its kind to date, predictive features including increasing metabolic tumor volume, increasing image heterogeneity, and increasing tumor surface irregularity significantly correlated to mortality, LF, and DM on 5 fold cross validation in a relatively uniform single-institution cohort. The LF model also retained significance in an independent population.
NASA Astrophysics Data System (ADS)
Luk, Alex T.; Lin, Yuting; Grimmond, Brian; Sood, Anup; Uzgiris, Egidijus E.; Nalcioglu, Orhan; Gulsen, Gultekin
2013-03-01
Since diffuse optical tomography (DOT) is a low spatial resolution modality, it is desirable to validate its quantitative accuracy with another well-established imaging modality, such as magnetic resonance imaging (MRI). In this work, we have used a polymer based bi-functional MRI-optical contrast agent (Gd-DTPA-polylysine-IR800) in collaboration with GE Global Research. This multi-modality contrast agent provided not only co-localization but also the same kinetics, to cross-validate two imaging modalities. Bi-functional agents are injected to the rats and pharmacokinetics at the bladder are recovered using both optical and MR imaging. DOT results are validated using MRI results as "gold standard"
The cross-cultural equivalence of participation instruments: a systematic review.
Stevelink, S A M; van Brakel, W H
2013-07-01
Concepts such as health-related quality of life, disability and participation may differ across cultures. Consequently, when assessing such a concept using a measure developed elsewhere, it is important to test its cultural equivalence. Previous research suggested a lack of cultural equivalence testing in several areas of measurement. This paper reviews the process of cross-cultural equivalence testing of instruments to measure participation in society. An existing cultural equivalence framework was adapted and used to assess participation instruments on five categories of equivalence: conceptual, item, semantic, measurement and operational equivalence. For each category, several aspects were rated, resulting in an overall category rating of 'minimal/none', 'partial' or 'extensive'. The best possible overall study rating was five 'extensive' ratings. Articles were included if the instruments focussed explicitly on measuring 'participation' and were theoretically grounded in the ICIDH(-2) or ICF. Cross-validation articles were only included if it concerned an adaptation of an instrument developed in a high or middle-income country to a low-income country or vice versa. Eight cross-cultural validation studies were included in which five participation instruments were tested (Impact on Participation and Autonomy, London Handicap Scale, Perceived Impact and Problem Profile, Craig Handicap Assessment Reporting Technique, Participation Scale). Of these eight studies, only three received at least two 'extensive' ratings for the different categories of equivalence. The majority of the cultural equivalence ratings given were 'partial' and 'minimal/none'. The majority of the 'none/minimal' ratings were given for item and measurement equivalence. The cross-cultural equivalence testing of the participation instruments included leaves much to be desired. A detailed checklist is proposed for designing a cross-validation study. Once a study has been conducted, the checklist can be used to ensure comprehensive reporting of the validation (equivalence) testing process and its results. • Participation instruments are often used in a different cultural setting than initial developed for. • The conceptualization of participation may vary across cultures. Therefore, cultural equivalence – the extent to which an instrument is equally suitable for use in two or more cultures – is an important concept to address. • This review showed that the process of cultural equivalence testing of the included participation instruments was often addressed insufficiently. • Clinicians should be aware that application of participations instruments in a different culture than initially developed for needs prior testing of cultural validity in the next context.
Validation and upgrading of physically based mathematical models
NASA Technical Reports Server (NTRS)
Duval, Ronald
1992-01-01
The validation of the results of physically-based mathematical models against experimental results was discussed. Systematic techniques are used for: (1) isolating subsets of the simulator mathematical model and comparing the response of each subset to its experimental response for the same input conditions; (2) evaluating the response error to determine whether it is the result of incorrect parameter values, incorrect structure of the model subset, or unmodeled external effects of cross coupling; and (3) modifying and upgrading the model and its parameter values to determine the most physically appropriate combination of changes.
Positron annihilation processes update
NASA Technical Reports Server (NTRS)
Guessoum, Nidhal; Skibo, Jeffrey G.; Ramaty, Reuven
1997-01-01
The present knowledge concerning the positron annihilation processes is reviewed, with emphasis on the data of the cross sections of the various processes of interest in astrophysical applications. Recent results are presented including results on reaction rates and line widths, the validity of which is verified.
Support vector machines and generalisation in HEP
NASA Astrophysics Data System (ADS)
Bevan, Adrian; Gamboa Goñi, Rodrigo; Hays, Jon; Stevenson, Tom
2017-10-01
We review the concept of Support Vector Machines (SVMs) and discuss examples of their use in a number of scenarios. Several SVM implementations have been used in HEP and we exemplify this algorithm using the Toolkit for Multivariate Analysis (TMVA) implementation. We discuss examples relevant to HEP including background suppression for H → τ + τ - at the LHC with several different kernel functions. Performance benchmarking leads to the issue of generalisation of hyper-parameter selection. The avoidance of fine tuning (over training or over fitting) in MVA hyper-parameter optimisation, i.e. the ability to ensure generalised performance of an MVA that is independent of the training, validation and test samples, is of utmost importance. We discuss this issue and compare and contrast performance of hold-out and k-fold cross-validation. We have extended the SVM functionality and introduced tools to facilitate cross validation in TMVA and present results based on these improvements.
Numerical and experimental analysis of an in-scale masonry cross-vault prototype up to failure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rossi, Michela; Calderini, Chiara; Lagomarsino, Sergio
2015-12-31
A heterogeneous full 3D non-linear FE approach is validated against experimental results obtained on an in-scale masonry cross vault assembled with dry joints, and subjected to various loading conditions consisting on imposed displacement combinations to the abutments. The FE model relies into a discretization of the blocks by means of few rigid-infinitely resistant parallelepiped elements interacting by means of planar four-noded interfaces, where all the deformation (elastic and inelastic) occurs. The investigated response mechanisms of vault are the shear in-plane distortion and the longitudinal opening and closing mechanism at the abutments. After the validation of the approach on the experimentallymore » tested cross-vault, a sensitivity analysis is conducted on the same geometry, but in real scale, varying mortar joints mechanical properties, in order to furnish useful hints for safety assessment, especially in presence of seismic action.« less
Large scale study of multiple-molecule queries
2009-01-01
Background In ligand-based screening, as well as in other chemoinformatics applications, one seeks to effectively search large repositories of molecules in order to retrieve molecules that are similar typically to a single molecule lead. However, in some case, multiple molecules from the same family are available to seed the query and search for other members of the same family. Multiple-molecule query methods have been less studied than single-molecule query methods. Furthermore, the previous studies have relied on proprietary data and sometimes have not used proper cross-validation methods to assess the results. In contrast, here we develop and compare multiple-molecule query methods using several large publicly available data sets and background. We also create a framework based on a strict cross-validation protocol to allow unbiased benchmarking for direct comparison in future studies across several performance metrics. Results Fourteen different multiple-molecule query methods were defined and benchmarked using: (1) 41 publicly available data sets of related molecules with similar biological activity; and (2) publicly available background data sets consisting of up to 175,000 molecules randomly extracted from the ChemDB database and other sources. Eight of the fourteen methods were parameter free, and six of them fit one or two free parameters to the data using a careful cross-validation protocol. All the methods were assessed and compared for their ability to retrieve members of the same family against the background data set by using several performance metrics including the Area Under the Accumulation Curve (AUAC), Area Under the Curve (AUC), F1-measure, and BEDROC metrics. Consistent with the previous literature, the best parameter-free methods are the MAX-SIM and MIN-RANK methods, which score a molecule to a family by the maximum similarity, or minimum ranking, obtained across the family. One new parameterized method introduced in this study and two previously defined methods, the Exponential Tanimoto Discriminant (ETD), the Tanimoto Power Discriminant (TPD), and the Binary Kernel Discriminant (BKD), outperform most other methods but are more complex, requiring one or two parameters to be fit to the data. Conclusion Fourteen methods for multiple-molecule querying of chemical databases, including novel methods, (ETD) and (TPD), are validated using publicly available data sets, standard cross-validation protocols, and established metrics. The best results are obtained with ETD, TPD, BKD, MAX-SIM, and MIN-RANK. These results can be replicated and compared with the results of future studies using data freely downloadable from http://cdb.ics.uci.edu/. PMID:20298525
Comparative docking and CoMFA analysis of curcumine derivatives as HIV-1 integrase inhibitors.
Gupta, Pawan; Garg, Prabha; Roy, Nilanjan
2011-08-01
The docking studies and comparative molecular field analysis (CoMFA) were performed on highly active molecules of curcumine derivatives against 3' processing activity of HIV-1 integrase (IN) enzyme. The optimum CoMFA model was selected with statistically significant cross-validated r(2) value of 0.815 and non-cross validated r (2) value of 0.99. The common pharmacophore of highly active molecules was used for screening of HIV-1 IN inhibitors. The high contribution of polar interactions in pharmacophore mapping is well supported by docking and CoMFA results. The results of docking, CoMFA, and pharmacophore mapping give structural insights as well as important binding features of curcumine derivatives as HIV-1 IN inhibitors which can provide guidance for the rational design of novel HIV-1 IN inhibitors.
Bairy, Santhosh Kumar; Suneel Kumar, B V S; Bhalla, Joseph Uday Tej; Pramod, A B; Ravikumar, Muttineni
2009-04-01
c-Src kinase play an important role in cell growth and differentiation and its inhibitors can be useful for the treatment of various diseases, including cancer, osteoporosis, and metastatic bone disease. Three dimensional quantitative structure-activity relationship (3D-QSAR) studies were carried out on quinazolin derivatives inhibiting c-Src kinase. Molecular field analysis (MFA) models with four different alignment techniques, namely, GLIDE, GOLD, LIGANDFIT and Least squares based methods were developed. glide based MFA model showed better results (Leave one out cross validation correlation coefficient r(2)(cv) = 0.923 and non-cross validation correlation coefficient r(2)= 0.958) when compared with other models. These results help us to understand the nature of descriptors required for activity of these compounds and thereby provide guidelines to design novel and potent c-Src kinase inhibitors.
Chiarotto, Alessandro; Vanti, Carla; Ostelo, Raymond W; Ferrari, Silvano; Tedesco, Giuseppe; Rocca, Barbara; Pillastrini, Paolo; Monticone, Marco
2015-11-01
The Pain Self-Efficacy Questionnaire (PSEQ) is a patient self-reported measurement instrument that evaluates pain self-efficacy beliefs in patients with chronic pain. The measurement properties of the PSEQ have been tested in its original and translated versions, showing satisfactory results for validity and reliability. The aims of this study were 2 fold as follows: (1) to translate the PSEQ into Italian through a process of cross-cultural adaptation, (2) to test the measurement properties of the Italian PSEQ (PSEQ-I). The cross-cultural adaptation was completed in 5 months without omitting any item of the original PSEQ. Measurement properties were tested in 165 patients with chronic low back pain (CLBP) (65% women, mean age 49.9 years). Factor analysis confirmed the one-factor structure of the questionnaire. Internal consistency (Cronbach's α = 0.94) and test-retest reliability (ICCagreement = 0.82) of the PSEQ-I showed good results. The smallest detectable change was equal to 15.69 scale points. The PSEQ-I displayed a high construct validity by meeting more than 75% of a priori hypotheses on correlations with measurement instruments assessing pain intensity, disability, anxiety, depression, pain catastrophizing, fear of movement, and coping strategies. Additionally, the PSEQ-I differentiated patients taking pain medication or not. The results of this study suggest that the PSEQ-I can be used as a valid and reliable tool in Italian patients with CLBP. © 2014 World Institute of Pain.
Prediction of adult height in girls: the Beunen-Malina-Freitas method.
Beunen, Gaston P; Malina, Robert M; Freitas, Duarte L; Thomis, Martine A; Maia, José A; Claessens, Albrecht L; Gouveia, Elvio R; Maes, Hermine H; Lefevre, Johan
2011-12-01
The purpose of this study was to validate and cross-validate the Beunen-Malina-Freitas method for non-invasive prediction of adult height in girls. A sample of 420 girls aged 10-15 years from the Madeira Growth Study were measured at yearly intervals and then 8 years later. Anthropometric dimensions (lengths, breadths, circumferences, and skinfolds) were measured; skeletal age was assessed using the Tanner-Whitehouse 3 method and menarcheal status (present or absent) was recorded. Adult height was measured and predicted using stepwise, forward, and maximum R (2) regression techniques. Multiple correlations, mean differences, standard errors of prediction, and error boundaries were calculated. A sample of the Leuven Longitudinal Twin Study was used to cross-validate the regressions. Age-specific coefficients of determination (R (2)) between predicted and measured adult height varied between 0.57 and 0.96, while standard errors of prediction varied between 1.1 and 3.9 cm. The cross-validation confirmed the validity of the Beunen-Malina-Freitas method in girls aged 12-15 years, but at lower ages the cross-validation was less consistent. We conclude that the Beunen-Malina-Freitas method is valid for the prediction of adult height in girls aged 12-15 years. It is applicable to European populations or populations of European ancestry.
Psychiatric diagnosis – is it universal or relative to culture?
Canino, Glorisa; Alegría, Margarita
2009-01-01
Background There is little consensus on the extent to which psychiatric disorders or syndromes are universal or the extent to which they differ on their core definitions and constellation of symptoms as a result of cultural or contextual factors. This controversy continues due to the lack of biological markers, imprecise measurement and the lack of a gold standard for validating most psychiatric conditions. Method Empirical studies were used to present evidence in favor of or against a universalist or relativistic view of child psychiatric disorders using a model developed by Robins and Guze to determine the validity of psychiatric disorders. Results The prevalence of some of the most common specific disorders and syndromes as well as its risk and protective factors vary across cultures, yet comorbid patterns and response to treatments vary little across cultures. Cross-cultural longitudinal data on outcomes is equivocal. Conclusions The cross-cultural validity of child disorders may vary drastically depending on the disorder, but empirical evidence that attests for the cross-cultural validity of diagnostic criteria for each child disorder is lacking. There is a need for studies that investigate the extent to which gene–environment interactions are related to specific disorders across cultures. Clinicians are urged to consider culture and context in determining the way in which children’s psychopathology may be manifested independent of their views. Recommendations for the upcoming classificatory system are provided so that practical or theoretical considerations are addressed about how culture and ethnic issues affect the assessment or treatment of specific disorders in children. PMID:18333929
Lee, Shin-Young; Lee, Eunice E
2015-02-01
The purpose of this study was to report the instrument modification and validation processes to make existing health belief model scales culturally appropriate for Korean Americans (KAs) regarding colorectal cancer (CRC) screening utilization. Instrument translation, individual interviews using cognitive interviewing, and expert reviews were conducted during the instrument modification phase, and a pilot test and a cross-sectional survey were conducted during the instrument validation phase. Data analyses of the cross-sectional survey included internal consistency and construct validity using exploratory and confirmatory factor analysis. The main issues identified during the instrument modification phase were (a) cultural and linguistic translation issues and (b) newly developed items reflecting Korean cultural barriers. Cross-sectional survey analyses during the instrument validation phase revealed that all scales demonstrate good internal consistency reliability (Cronbach's alpha=.72~.88). Exploratory factor analysis showed that susceptibility and severity loaded on the same factor, which may indicate a threat variable. Items with low factor loadings in the confirmatory factor analysis may relate to (a) lack of knowledge about fecal occult blood testing and (b) multiple dimensions of the subscales. Methodological, sequential processes of instrument modification and validation, including translation, individual interviews, expert reviews, pilot testing and a cross-sectional survey, were provided in this study. The findings indicate that existing instruments need to be examined for CRC screening research involving KAs.
Haslinger-Baumann, Elisabeth; Lang, Gert; Müller, Gerhard
2014-01-01
In nursing practice, research results have to undergo a systematic process of transformation. Currently in Austria, there is no empirical data available concerning the actual implementation of research results. An English validated questionnaire was translated into German and tested for validity and reliability. A survey of 178 registered nurses (n = 178) was conducted in a multicenter, quantitative, cross-sectional study in Austria in 2011. Cronbach's alpha values (.82-.92) were calculated for 4 variables ("use," "attitude," "availability," "support") after the reduction of 7 irrelevant items. Exploratory factor analysis was calculated with Kaiser-Meyer-Olkin (KMO) ranging from .78 to .92; the total variance ranged from 46% to 56%. A validated German questionnaire concerning the implementation of research results is now available for the nursing practice.
Construction and validation of forms: systematization of the care of people under hemodialysis.
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.
Cross-Cultural Validation of the Five-Factor Structure of Social Goals: A Filipino Investigation
ERIC Educational Resources Information Center
King, Ronnel B.; Watkins, David A.
2012-01-01
The aim of the present study was to test the cross-cultural validity of the five-factor structure of social goals that Dowson and McInerney proposed. Using both between-network and within-network approaches to construct validation, 1,147 Filipino high school students participated in the study. Confirmatory factor analysis indicated that the…
Hill, Mary C.; L. Foglia,; S. W. Mehl,; P. Burlando,
2013-01-01
Model adequacy is evaluated with alternative models rated using model selection criteria (AICc, BIC, and KIC) and three other statistics. Model selection criteria are tested with cross-validation experiments and insights for using alternative models to evaluate model structural adequacy are provided. The study is conducted using the computer codes UCODE_2005 and MMA (MultiModel Analysis). One recharge alternative is simulated using the TOPKAPI hydrological model. The predictions evaluated include eight heads and three flows located where ecological consequences and model precision are of concern. Cross-validation is used to obtain measures of prediction accuracy. Sixty-four models were designed deterministically and differ in representation of river, recharge, bedrock topography, and hydraulic conductivity. Results include: (1) What may seem like inconsequential choices in model construction may be important to predictions. Analysis of predictions from alternative models is advised. (2) None of the model selection criteria consistently identified models with more accurate predictions. This is a disturbing result that suggests to reconsider the utility of model selection criteria, and/or the cross-validation measures used in this work to measure model accuracy. (3) KIC displayed poor performance for the present regression problems; theoretical considerations suggest that difficulties are associated with wide variations in the sensitivity term of KIC resulting from the models being nonlinear and the problems being ill-posed due to parameter correlations and insensitivity. The other criteria performed somewhat better, and similarly to each other. (4) Quantities with high leverage are more difficult to predict. The results are expected to be generally applicable to models of environmental systems.
Yapali, Gökmen; Günel, Mintaze Kerem; Karahan, Sevilay
2012-05-15
The study design was cross-cultural adaptation and investigation of reliability and validity of the Copenhagen Neck Functional Disability Scale (CNFDS). The aim of this study was to translate the CNFDS into Turkish language and assess its reliability and validity among patients with neck pain in Turkish population. The CNFDS is a reliable and valid evaluation instrument for disability, but there is no published the Turkish version of the CNFDS. One hundred one subjects who had chronic neck pain were included in this study. The CNFDS, Neck Pain and Disability Scale, and visual analogue scale were administered to all subjects. For investigating test-retest reliability, correlation between CNFDS scores, applied at 1-week interval, intraclass correlation coefficient score for test-retest reliability was 0.86 (95% confidence interval = 0.679-0.935). There was no difference between test-retest scores (P < 0.001). For investigating concurrent validity, correlation between total score of the CNFDS and the mean visual analogue scale was r = 0.73 (P < 0.001). Concurrent validity of the CNFDS was very good. For investigating construct validity, correlation between total score of the CNFDS and the Neck Pain and Disability Scale was r = 0.78 (P < 0.001). Construct validity of the CNFDS was also very good. Our results suggest that the Turkish version of the CNFDS is a reliable and valid instrument for Turkish people.
Knowledge discovery by accuracy maximization
Cacciatore, Stefano; Luchinat, Claudio; Tenori, Leonardo
2014-01-01
Here we describe KODAMA (knowledge discovery by accuracy maximization), an unsupervised and semisupervised learning algorithm that performs feature extraction from noisy and high-dimensional data. Unlike other data mining methods, the peculiarity of KODAMA is that it is driven by an integrated procedure of cross-validation of the results. The discovery of a local manifold’s topology is led by a classifier through a Monte Carlo procedure of maximization of cross-validated predictive accuracy. Briefly, our approach differs from previous methods in that it has an integrated procedure of validation of the results. In this way, the method ensures the highest robustness of the obtained solution. This robustness is demonstrated on experimental datasets of gene expression and metabolomics, where KODAMA compares favorably with other existing feature extraction methods. KODAMA is then applied to an astronomical dataset, revealing unexpected features. Interesting and not easily predictable features are also found in the analysis of the State of the Union speeches by American presidents: KODAMA reveals an abrupt linguistic transition sharply separating all post-Reagan from all pre-Reagan speeches. The transition occurs during Reagan’s presidency and not from its beginning. PMID:24706821
Chung, Hui-Chun; Hsieh, Tsung-Cheng; Chen, Yueh-Chih; Chang, Shu-Chuan; Hsu, Wen-Lin
2017-11-29
To investigate the construct validity and reliability of the Chinese Comfort, Afford, Respect, and Expect scale, which can be used to determine clinical nurses' competence. The results can also serve to promote nursing competence and improve patient satisfaction. Nurse-patient interaction is critical for improving nursing care quality. However, to date, no relevant validated instrument has been proposed for assessing caring nurse-patient interaction competence in clinical practice. This study adapted and validated the Chinese version of the caring nurse-patient interaction scale. A cross-cultural adaptation and validation study. A psychometric analysis of the four major constructs of the Chinese Comfort, Afford, Respect, and Expect scale was conducted on a sample of 356 nurses from a medical centre in China. Item analysis and exploratory factor analysis were adopted to extract the main components, both the internal consistency and correlation coefficients were used to examine reliability and a confirmatory factor analysis was adopted to verify the construct validity. The goodness-of-fit results of the model were strong. The standardised factor loadings of the Chinese Comfort, Afford, Respect, and Expect scale ranged from 0.73-0.95, indicating that the validity and reliability of this instrument were favourable. Moreover, the 12 extracted items explained 95.9% of the measured content of the Chinese Comfort, Afford, Respect, and Expect scale. The results serve as empirical evidence regarding the validity and reliability of the Chinese Comfort, Afford, Respect, and Expect scale. Hospital nurses increasingly demand help from patients and their family members in identifying health problems and assisting with medical decision-making. Therefore, enhancing nurses' competence in nurse-patient interactions is crucial for nursing and hospital managers to improve nursing care quality. The Chinese caring nurse-patient interaction scale can serve as an effective tool for nursing and hospital managers to evaluate the caring nurse-patient interaction confidence of nurses and improve inpatient satisfaction and quality of care. © 2017 John Wiley & Sons Ltd.
Schmidt, Stine N; Wang, Alice P; Gidley, Philip T; Wooley, Allyson H; Lotufo, Guilherme R; Burgess, Robert M; Ghosh, Upal; Fernandez, Loretta A; Mayer, Philipp
2017-09-05
The Gold Standard for determining freely dissolved concentrations (C free ) of hydrophobic organic compounds in sediment interstitial water would be in situ deployment combined with equilibrium sampling, which is generally difficult to achieve. In the present study, ex situ equilibrium sampling with multiple thicknesses of silicone and in situ pre-equilibrium sampling with low density polyethylene (LDPE) loaded with performance reference compounds were applied independently to measure polychlorinated biphenyls (PCBs) in mesocosms with (1) New Bedford Harbor sediment (MA, U.S.A.), (2) sediment and biota, and (3) activated carbon amended sediment and biota. The aim was to cross validate the two different sampling approaches. Around 100 PCB congeners were quantified in the two sampling polymers, and the results confirmed the good precision of both methods and were in overall good agreement with recently published LDPE to silicone partition ratios. Further, the methods yielded C free in good agreement for all three experiments. The average ratio between C free determined by the two methods was factor 1.4 ± 0.3 (range: 0.6-2.0), and the results thus cross-validated the two sampling approaches. For future investigations, specific aims and requirements in terms of application, data treatment, and data quality requirements should dictate the selection of the most appropriate partitioning-based sampling approach.
The validity and reliability of tinnitus handicap inventory Thai version.
Limviriyakul, Siriporn; Supavanich, Walop
2012-11-01
Demonstrate the reliability and validity of the Tinnitus Handicap Inventory Thai Version (THI-T), a self-report measure of tinnitus. A cross-sectional psychometric validation study was used to determine internal consistency reliability and validity of the Tinnitus Handicap Inventory Thai Version at the Otoneurology clinic at Tertiary care center The cross-cultural adaptation of the Tinnitus Handicapped Inventory English version (Newman et al, 1996) was translated into Thai version following the steps indicated by Guillemin et al. The reliability was constructed by using Cronbach's coefficient alpha. The validity was analyzed by the correlation between Tinnitus Handicap Inventory Thai version and the 36-items short form health survey and visual analog scale using Spearman and Pearson test. The result showed good internal consistency reliabilities of total, functional, emotional, and catastrophic scale (a = 0.902, 0.804, 0.831 and 0.661, respectively) of Tinnitus Handicap Inventory Thai Version. Spearman correlation showed the significant correlation of Tinnitus Handicap Inventory to 36-items short form health survey and visual analog scale. Tinnitus Handicap Inventory Thai Version will be a vigorous tool in evaluating tinnitus patients as well as monitoring the progress of their symptoms.
Uncertainty Quantification Techniques of SCALE/TSUNAMI
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rearden, Bradley T; Mueller, Don
2011-01-01
The Standardized Computer Analysis for Licensing Evaluation (SCALE) code system developed at Oak Ridge National Laboratory (ORNL) includes Tools for Sensitivity and Uncertainty Analysis Methodology Implementation (TSUNAMI). The TSUNAMI code suite can quantify the predicted change in system responses, such as k{sub eff}, reactivity differences, or ratios of fluxes or reaction rates, due to changes in the energy-dependent, nuclide-reaction-specific cross-section data. Where uncertainties in the neutron cross-section data are available, the sensitivity of the system to the cross-section data can be applied to propagate the uncertainties in the cross-section data to an uncertainty in the system response. Uncertainty quantification ismore » useful for identifying potential sources of computational biases and highlighting parameters important to code validation. Traditional validation techniques often examine one or more average physical parameters to characterize a system and identify applicable benchmark experiments. However, with TSUNAMI correlation coefficients are developed by propagating the uncertainties in neutron cross-section data to uncertainties in the computed responses for experiments and safety applications through sensitivity coefficients. The bias in the experiments, as a function of their correlation coefficient with the intended application, is extrapolated to predict the bias and bias uncertainty in the application through trending analysis or generalized linear least squares techniques, often referred to as 'data adjustment.' Even with advanced tools to identify benchmark experiments, analysts occasionally find that the application models include some feature or material for which adequately similar benchmark experiments do not exist to support validation. For example, a criticality safety analyst may want to take credit for the presence of fission products in spent nuclear fuel. In such cases, analysts sometimes rely on 'expert judgment' to select an additional administrative margin to account for gap in the validation data or to conclude that the impact on the calculated bias and bias uncertainty is negligible. As a result of advances in computer programs and the evolution of cross-section covariance data, analysts can use the sensitivity and uncertainty analysis tools in the TSUNAMI codes to estimate the potential impact on the application-specific bias and bias uncertainty resulting from nuclides not represented in available benchmark experiments. This paper presents the application of methods described in a companion paper.« less
Validating LES for Jet Aeroacoustics
NASA Technical Reports Server (NTRS)
Bridges, James
2011-01-01
Engineers charged with making jet aircraft quieter have long dreamed of being able to see exactly how turbulent eddies produce sound and this dream is now coming true with the advent of large eddy simulation (LES). Two obvious challenges remain: validating the LES codes at the resolution required to see the fluid-acoustic coupling, and the interpretation of the massive datasets that result in having dreams come true. This paper primarily addresses the former, the use of advanced experimental techniques such as particle image velocimetry (PIV) and Raman and Rayleigh scattering, to validate the computer codes and procedures used to create LES solutions. It also addresses the latter problem in discussing what are relevant measures critical for aeroacoustics that should be used in validating LES codes. These new diagnostic techniques deliver measurements and flow statistics of increasing sophistication and capability, but what of their accuracy? And what are the measures to be used in validation? This paper argues that the issue of accuracy be addressed by cross-facility and cross-disciplinary examination of modern datasets along with increased reporting of internal quality checks in PIV analysis. Further, it is argued that the appropriate validation metrics for aeroacoustic applications are increasingly complicated statistics that have been shown in aeroacoustic theory to be critical to flow-generated sound.
Cross-cultural adaptation and validation of the teamwork climate scale
Silva, Mariana Charantola; Peduzzi, Marina; Sangaleti, Carine Teles; da Silva, Dirceu; Agreli, Heloise Fernandes; West, Michael A; Anderson, Neil R
2016-01-01
ABSTRACT OBJECTIVE To adapt and validate the Team Climate Inventory scale, of teamwork climate measurement, for the Portuguese language, in the context of primary health care in Brazil. METHODS Methodological study with quantitative approach of cross-cultural adaptation (translation, back-translation, synthesis, expert committee, and pretest) and validation with 497 employees from 72 teams of the Family Health Strategy in the city of Campinas, SP, Southeastern Brazil. We verified reliability by the Cronbach’s alpha, construct validity by the confirmatory factor analysis with SmartPLS software, and correlation by the job satisfaction scale. RESULTS We problematized the overlap of items 9, 11, and 12 of the “participation in the team” factor and the “team goals” factor regarding its definition. The validation showed no overlapping of items and the reliability ranged from 0.92 to 0.93. The confirmatory factor analysis indicated suitability of the proposed model with distribution of the 38 items in the four factors. The correlation between teamwork climate and job satisfaction was significant. CONCLUSIONS The version of the scale in Brazilian Portuguese was validated and can be used in the context of primary health care in the Country, constituting an adequate tool for the assessment and diagnosis of teamwork. PMID:27556966
Assessing cross-cultural validity of scales: a methodological review and illustrative example.
Beckstead, Jason W; Yang, Chiu-Yueh; Lengacher, Cecile A
2008-01-01
In this article, we assessed the cross-cultural validity of the Women's Role Strain Inventory (WRSI), a multi-item instrument that assesses the degree of strain experienced by women who juggle the roles of working professional, student, wife and mother. Cross-cultural validity is evinced by demonstrating the measurement invariance of the WRSI. Measurement invariance is the extent to which items of multi-item scales function in the same way across different samples of respondents. We assessed measurement invariance by comparing a sample of working women in Taiwan with a similar sample from the United States. Structural equation models (SEMs) were employed to determine the invariance of the WRSI and to estimate the unique validity variance of its items. This article also provides nurse-researchers with the necessary underlying measurement theory and illustrates how SEMs may be applied to assess cross-cultural validity of instruments used in nursing research. Overall performance of the WRSI was acceptable but our analysis showed that some items did not display invariance properties across samples. Item analysis is presented and recommendations for improving the instrument are discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lin, H; Liu, T; Xu, X
Purpose: There are clinical decision challenges to select optimal treatment positions for left-sided breast cancer patients—supine free breathing (FB), supine Deep Inspiration Breath Hold (DIBH) and prone free breathing (prone). Physicians often make the decision based on experiences and trials, which might not always result optimal OAR doses. We herein propose a mathematical model to predict the lowest OAR doses among these three positions, providing a quantitative tool for corresponding clinical decision. Methods: Patients were scanned in FB, DIBH, and prone positions under an IRB approved protocol. Tangential beam plans were generated for each position, and OAR doses were calculated.more » The position with least OAR doses is defined as the optimal position. The following features were extracted from each scan to build the model: heart, ipsilateral lung, breast volume, in-field heart, ipsilateral lung volume, distance between heart and target, laterality of heart, and dose to heart and ipsilateral lung. Principal Components Analysis (PCA) was applied to remove the co-linearity of the input data and also to lower the data dimensionality. Feature selection, another method to reduce dimensionality, was applied as a comparison. Support Vector Machine (SVM) was then used for classification. Thirtyseven patient data were acquired; up to now, five patient plans were available. K-fold cross validation was used to validate the accuracy of the classifier model with small training size. Results: The classification results and K-fold cross validation demonstrated the model is capable of predicting the optimal position for patients. The accuracy of K-fold cross validations has reached 80%. Compared to PCA, feature selection allows causal features of dose to be determined. This provides more clinical insights. Conclusion: The proposed classification system appeared to be feasible. We are generating plans for the rest of the 37 patient images, and more statistically significant results are to be presented.« less
Botti, Mari; Khaw, Damien; Jørgensen, Emmy Brandt; Rasmussen, Bodil; Hunter, Susan; Redley, Bernice
2015-08-01
This study investigated the cross-cultural factor stability and internal consistency of the Revised American Pain Society Patient Outcome Questionnaire (APS-POQ-R), a measure of the quality of postoperative pain management used internationally. We conducted exploratory factor analysis (EFA) of APS-POQ-R data from 2 point prevalence studies comprising 268 and 311 surveys of Danish and Australian medical-surgical patients, respectively. Parallel analysis indicated 4- and 3-factor solutions for Danish and Australian patients, respectively, which accounted for 58.1% and 52.9% of variance. Internal consistency was unsatisfactory among both Danish (Cronbach α = .54) and Australian (Cronbach α = .63) cohorts. There was a high degree of between-group similarity in item-factor loadings of variables coded as "pain experience," but not "pain management." This finding reflected cross-cultural differences in ratings of treatment satisfaction. For Danish patients, satisfaction was associated with the degree of pain severity and activity interference, whereas for Australian patients, satisfaction was associated with their perceived ability to participate in treatment. To facilitate further cross-cultural comparison, we compared our findings with past research conducted in the United States and Iceland. EFA supported the construct validity of the APS-POQ-R as a measure of "pain experience" but indicated that items measuring "pain management" may vary cross-culturally. Findings highlighted the need for further validation of the APS-POQ-R internationally. This study revealed the APS-POQ-R as a valid measure of postoperative pain experience for Danish and Australian patients. Measures of patients' perception of pain management were not robust to group differences in treatment expectations and demonstrated cross-cultural instability. Results highlighted the difficulties in establishing stable cross-cultural, cross-population subscales for the APS-POQ-R. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Fromm, Germán; Hallinger, Philip; Volante, Paulo; Wang, Wen Chung
2017-01-01
The purposes of this study were to report on a systematic approach to validating a Spanish version of the Principal Instructional Management Rating Scale and then to apply the scale in a cross-national comparison of principal instructional leadership. The study yielded a validated Spanish language version of the PIMRS Teacher Form and offers a…
Niemeijer, Anuschka S; van Waelvelde, Hilde; Smits-Engelsman, Bouwien C M
2015-02-01
The Movement Assessment Battery for Children has been revised as the Movement ABC-2 (Henderson, Sugden, & Barnett, 2007). In Europe, the 15th percentile score on this test is recommended for one of the DSM-IV diagnostic criteria for Developmental Coordination Disorder (DCD). A representative sample of Dutch and Flemish children was tested to cross-validate the UK standard scores, including the 15th percentile score. First, the mean, SD and percentile scores of Dutch children were compared to those of UK normative samples. Item standard scores of Dutch speaking children deviated from the UK reference values suggesting necessary adjustments. Except for very young children, the Dutch-speaking samples performed better. Second, based on the mean and SD and clinical relevant cut-off scores (5th and 15th percentile), norms were adjusted for the Dutch population. For diagnostic use, researchers and clinicians should use the reference norms that are valid for the group of children they are testing. The results indicate that there possibly is an effect of testing procedure in other countries that validated the UK norms and/or cultural influence on the age norms of the Movement ABC-2. It is suggested to formulate criterion-based norms for age groups in addition to statistical norms. Copyright © 2014 Elsevier B.V. All rights reserved.
Brazilian validation of the Alberta Infant Motor Scale.
Valentini, Nadia Cristina; Saccani, Raquel
2012-03-01
The Alberta Infant Motor Scale (AIMS) is a well-known motor assessment tool used to identify potential delays in infants' motor development. Although Brazilian researchers and practitioners have used the AIMS in laboratories and clinical settings, its translation to Portuguese and validation for the Brazilian population is yet to be investigated. This study aimed to translate and validate all AIMS items with respect to internal consistency and content, criterion, and construct validity. A cross-sectional and longitudinal design was used. A cross-cultural translation was used to generate a Brazilian-Portuguese version of the AIMS. In addition, a validation process was conducted involving 22 professionals and 766 Brazilian infants (aged 0-18 months). The results demonstrated language clarity and internal consistency for the motor criteria (motor development score, α=.90; prone, α=.85; supine, α=.92; sitting, α=.84; and standing, α=.86). The analysis also revealed high discriminative power to identify typical and atypical development (motor development score, P<.001; percentile, P=.04; classification criterion, χ(2)=6.03; P=.05). Temporal stability (P=.07) (rho=.85, P<.001) was observed, and predictive power (P<.001) was limited to the group of infants aged from 3 months to 9 months. Limited predictive validity was observed, which may have been due to the restricted time that the groups were followed longitudinally. In sum, the translated version of AIMS presented adequate validity and reliability.
Dhingra, Madhur S; Artois, Jean; Robinson, Timothy P; Linard, Catherine; Chaiban, Celia; Xenarios, Ioannis; Engler, Robin; Liechti, Robin; Kuznetsov, Dmitri; Xiao, Xiangming; Dobschuetz, Sophie Von; Claes, Filip; Newman, Scott H; Dauphin, Gwenaëlle; Gilbert, Marius
2016-01-01
Global disease suitability models are essential tools to inform surveillance systems and enable early detection. We present the first global suitability model of highly pathogenic avian influenza (HPAI) H5N1 and demonstrate that reliable predictions can be obtained at global scale. Best predictions are obtained using spatial predictor variables describing host distributions, rather than land use or eco-climatic spatial predictor variables, with a strong association with domestic duck and extensively raised chicken densities. Our results also support a more systematic use of spatial cross-validation in large-scale disease suitability modelling compared to standard random cross-validation that can lead to unreliable measure of extrapolation accuracy. A global suitability model of the H5 clade 2.3.4.4 viruses, a group of viruses that recently spread extensively in Asia and the US, shows in comparison a lower spatial extrapolation capacity than the HPAI H5N1 models, with a stronger association with intensively raised chicken densities and anthropogenic factors. DOI: http://dx.doi.org/10.7554/eLife.19571.001 PMID:27885988
A Machine Learning Framework for Plan Payment Risk Adjustment.
Rose, Sherri
2016-12-01
To introduce cross-validation and a nonparametric machine learning framework for plan payment risk adjustment and then assess whether they have the potential to improve risk adjustment. 2011-2012 Truven MarketScan database. We compare the performance of multiple statistical approaches within a broad machine learning framework for estimation of risk adjustment formulas. Total annual expenditure was predicted using age, sex, geography, inpatient diagnoses, and hierarchical condition category variables. The methods included regression, penalized regression, decision trees, neural networks, and an ensemble super learner, all in concert with screening algorithms that reduce the set of variables considered. The performance of these methods was compared based on cross-validated R 2 . Our results indicate that a simplified risk adjustment formula selected via this nonparametric framework maintains much of the efficiency of a traditional larger formula. The ensemble approach also outperformed classical regression and all other algorithms studied. The implementation of cross-validated machine learning techniques provides novel insight into risk adjustment estimation, possibly allowing for a simplified formula, thereby reducing incentives for increased coding intensity as well as the ability of insurers to "game" the system with aggressive diagnostic upcoding. © Health Research and Educational Trust.
Triacylglycerol stereospecific analysis and linear discriminant analysis for milk speciation.
Blasi, Francesca; Lombardi, Germana; Damiani, Pietro; Simonetti, Maria Stella; Giua, Laura; Cossignani, Lina
2013-05-01
Product authenticity is an important topic in dairy sector. Dairy products sold for public consumption must be accurately labelled in accordance with the contained milk species. Linear discriminant analysis (LDA), a common chemometric procedure, has been applied to fatty acid% composition to classify pure milk samples (cow, ewe, buffalo, donkey, goat). All original grouped cases were correctly classified, while 90% of cross-validated grouped cases were correctly classified. Another objective of this research was the characterisation of cow-ewe milk mixtures in order to reveal a common fraud in dairy field, that is the addition of cow to ewe milk. Stereospecific analysis of triacylglycerols (TAG), a method based on chemical-enzymatic procedures coupled with chromatographic techniques, has been carried out to detect fraudulent milk additions, in particular 1, 3, 5% cow milk added to ewe milk. When only TAG composition data were used for the elaboration, 75% of original grouped cases were correctly classified, while totally correct classified samples were obtained when both total and intrapositional TAG data were used. Also the results of cross validation were better when TAG stereospecific analysis data were considered as LDA variables. In particular, 100% of cross-validated grouped cases were obtained when 5% cow milk mixtures were considered.
Finn, James E.; Burger, Carl V.; Holland-Bartels, Leslie E.
1997-01-01
We used otolith banding patterns formed during incubation to discriminate among hatchery- and wild-incubated fry of sockeye salmon Oncorhynchus nerka from Tustumena Lake, Alaska. Fourier analysis of otolith luminance profiles was used to describe banding patterns: the amplitudes of individual Fourier harmonics were discriminant variables. Correct classification of otoliths to either hatchery or wild origin was 83.1% (cross-validation) and 72.7% (test data) with the use of quadratic discriminant function analysts on 10 Fourier amplitudes. Overall classification rates among the six test groups (one hatchery and five wild groups) were 46.5% (cross-validation) and 39.3% (test data) with the use of linear discriminant function analysis on 16 Fourier amplitudes. Although classification rates for wild-incubated fry from any one site never exceeded 67% (cross-validation) or 60% (test data), location-specific information was evident for all groups because the probability of classifying an individual to its true incubation location was significantly greater than chance. Results indicate phenotypic differences in otolith microstructure among incubation sites separated by less than 10 km. Analysis of otolith luminance profiles is a potentially useful technique for discriminating among and between various populations of hatchery and wild fish.
Lima, Elaine; Teixeira-Salmela, Luci F.; Simões, Luan; Guerra, Ana C. C.; Lemos, Andrea
2016-01-01
Background While there are several instruments in Brazil that measure motor function in patients after stroke, it is unknown whether the measurement properties of these instruments are appropriate. Objective To identify the motor function instruments available in Brazil for patients after stroke. To assess the methodological quality of the studies and the results related to the measurement properties of these instruments. Method Two independent reviewers conducted searches on PubMed, LILACS, CINAHL, Web of Science, and Scopus. Studies that aimed to cross-culturally adapt an existing instrument or create a Brazilian instrument and test at least one measurement property related to motor function in patients after stroke were included. The methodological quality of these studies was checked by the COSMIN checklist with 4-point rating scale and the results of the measurement properties were analyzed by the criteria developed by Terwee et al. Results A total of 11 instruments were considered eligible, none of which were created in Brazil. The process of cross-cultural adaptation was inadequate in 10 out of 11 instruments due to the lack of back-translation or due to inappropriate target population. All of the instruments presented flaws in the measurement properties, especially reliability, internal consistency, and construct validity. Conclusion The flaws observed in both cross-cultural adaptation process and testing measurement properties make the results inconclusive on the validity of the available instruments. Adequate procedures of cross-cultural adaptation and measurement properties of these instruments are strongly needed. PMID:26982452
Jain, Meena; Tandon, Shourya; Sharma, Ankur; Jain, Vishal; Rani Yadav, Nisha
2018-01-01
Background: An appropriate scale to assess the dental anxiety of Hindi speaking population is lacking. This study, therefore, aims to evaluate the psychometric properties of Hindi version of one of the oldest dental anxiety scale, Corah’s Dental Anxiety Scale (CDAS) in Hindi speaking Indian adults. Methods: A total of 348 subjects from the outpatient department of a dental hospital in India participated in this cross-sectional study. The scale was cross-culturally adapted by forward and backward translation, committee review and pretesting method. The construct validity of the translated scale was explored with exploratory factor analysis. The correlation of the Hindi version of CDAS with visual analogue scale (VAS) was used to measure the convergent validity. Reliability was assessed through calculations of Cronbach’s alpha and intra class correlation 48 forms were completed for test-retest. Results: Prevalence of dental anxiety in the sample within the age range of 18-80 years was 85.63% [95% CI: 0.815-0.891]. The response rate was 100 %. Kaiser-Meyer-Olkin (KMO) test value was 0.776. After factor analysis, a single factor (dental anxiety) was obtained with 4 items.The single factor model explained 61% variance. Pearson correlation coefficient between CDASand VAS was 0.494. Test-retest showed the Cronbach’s alpha value of 0.814. The test-retest intraclass correlation coefficient of the total CDAS score was 0.881 [95% CI: 0.318-0.554]. Conclusion: Hindi version of CDAS is a valid and reliable scale to assess dental anxiety in Hindi speaking population. Convergent validity is well recognized but discriminant validity is limited and requires further study. PMID:29744307
Jain, Meena; Tandon, Shourya; Sharma, Ankur; Jain, Vishal; Rani Yadav, Nisha
2018-01-01
Background: An appropriate scale to assess the dental anxiety of Hindi speaking population is lacking. This study, therefore, aims to evaluate the psychometric properties of Hindi version of one of the oldest dental anxiety scale, Corah's Dental Anxiety Scale (CDAS) in Hindi speaking Indian adults. Methods: A total of 348 subjects from the outpatient department of a dental hospital in India participated in this cross-sectional study. The scale was cross-culturally adapted by forward and backward translation, committee review and pretesting method. The construct validity of the translated scale was explored with exploratory factor analysis. The correlation of the Hindi version of CDAS with visual analogue scale (VAS) was used to measure the convergent validity. Reliability was assessed through calculations of Cronbach's alpha and intra class correlation 48 forms were completed for test-retest. Results: Prevalence of dental anxiety in the sample within the age range of 18-80 years was 85.63% [95% CI: 0.815-0.891]. The response rate was 100 %. Kaiser-Meyer-Olkin (KMO) test value was 0.776. After factor analysis, a single factor (dental anxiety) was obtained with 4 items.The single factor model explained 61% variance. Pearson correlation coefficient between CDASand VAS was 0.494. Test-retest showed the Cronbach's alpha value of 0.814. The test-retest intraclass correlation coefficient of the total CDAS score was 0.881 [95% CI: 0.318-0.554]. Conclusion: Hindi version of CDAS is a valid and reliable scale to assess dental anxiety in Hindi speaking population. Convergent validity is well recognized but discriminant validity is limited and requires further study.
Messner, Steven F.; Raffalovich, Lawrence E.; Sutton, Gretchen M.
2011-01-01
This paper assesses the extent to which the infant mortality rate might be treated as a “proxy” for poverty in research on cross-national variation in homicide rates. We have assembled a pooled, cross-sectional time-series dataset for 16 advanced nations over the 1993–2000 period that includes standard measures of infant mortality and homicide and also contains information on two commonly used “income-based” poverty measures: a measure intended to reflect “absolute” deprivation and a measure intended to reflect “relative” deprivation. With these data, we are able to assess the criterion validity of the infant mortality rate with reference to the two income-based poverty measures. We are also able to estimate the effects of the various indicators of disadvantage on homicide rates in regression models, thereby assessing construct validity. The results reveal that the infant mortality rate is more strongly correlated with “relative poverty” than with “absolute poverty,” although much unexplained variance remains. In the regression models, the measure of infant mortality and the relative poverty measure yield significant positive effects on homicide rates, while the absolute poverty measure does not exhibit any significant effects. Our analyses suggest that it would be premature to dismiss relative deprivation in cross-national research on homicide, and that disadvantage is best conceptualized and measured as a multidimensional construct. PMID:21643432
2014-01-01
Background Health impairments can result in disability and changed work productivity imposing considerable costs for the employee, employer and society as a whole. A large number of instruments exist to measure health-related productivity changes; however their methodological quality remains unclear. This systematic review critically appraised the measurement properties in generic self-reported instruments that measure health-related productivity changes to recommend appropriate instruments for use in occupational and economic health practice. Methods PubMed, PsycINFO, Econlit and Embase were systematically searched for studies whereof: (i) instruments measured health-related productivity changes; (ii) the aim was to evaluate instrument measurement properties; (iii) instruments were generic; (iv) ratings were self-reported; (v) full-texts were available. Next, methodological quality appraisal was based on COSMIN elements: (i) internal consistency; (ii) reliability; (iii) measurement error; (iv) content validity; (v) structural validity; (vi) hypotheses testing; (vii) cross-cultural validity; (viii) criterion validity; and (ix) responsiveness. Recommendations are based on evidence syntheses. Results This review included 25 articles assessing the reliability, validity and responsiveness of 15 different generic self-reported instruments measuring health-related productivity changes. Most studies evaluated criterion validity, none evaluated cross-cultural validity and information on measurement error is lacking. The Work Limitation Questionnaire (WLQ) was most frequently evaluated with moderate respectively strong positive evidence for content and structural validity and negative evidence for reliability, hypothesis testing and responsiveness. Less frequently evaluated, the Stanford Presenteeism Scale (SPS) showed strong positive evidence for internal consistency and structural validity, and moderate positive evidence for hypotheses testing and criterion validity. The Productivity and Disease Questionnaire (PRODISQ) yielded strong positive evidence for content validity, evidence for other properties is lacking. The other instruments resulted in mostly fair-to-poor quality ratings with limited evidence. Conclusions Decisions based on the content of the instrument, usage purpose, target country and population, and available evidence are recommended. Until high-quality studies are in place to accurately assess the measurement properties of the currently available instruments, the WLQ and, in a Dutch context, the PRODISQ are cautiously preferred based on its strong positive evidence for content validity. Based on its strong positive evidence for internal consistency and structural validity, the SPS is cautiously recommended. PMID:24495301
Exploration of Force Myography and surface Electromyography in hand gesture classification.
Jiang, Xianta; Merhi, Lukas-Karim; Xiao, Zhen Gang; Menon, Carlo
2017-03-01
Whereas pressure sensors increasingly have received attention as a non-invasive interface for hand gesture recognition, their performance has not been comprehensively evaluated. This work examined the performance of hand gesture classification using Force Myography (FMG) and surface Electromyography (sEMG) technologies by performing 3 sets of 48 hand gestures using a prototyped FMG band and an array of commercial sEMG sensors worn both on the wrist and forearm simultaneously. The results show that the FMG band achieved classification accuracies as good as the high quality, commercially available, sEMG system on both wrist and forearm positions; specifically, by only using 8 Force Sensitive Resisters (FSRs), the FMG band achieved accuracies of 91.2% and 83.5% in classifying the 48 hand gestures in cross-validation and cross-trial evaluations, which were higher than those of sEMG (84.6% and 79.1%). By using all 16 FSRs on the band, our device achieved high accuracies of 96.7% and 89.4% in cross-validation and cross-trial evaluations. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.
Cross-cultural adaptation and validation of Persian Achilles tendon Total Rupture Score.
Ansari, Noureddin Nakhostin; Naghdi, Soofia; Hasanvand, Sahar; Fakhari, Zahra; Kordi, Ramin; Nilsson-Helander, Katarina
2016-04-01
To cross-culturally adapt the Achilles tendon Total Rupture Score (ATRS) to Persian language and to preliminary evaluate the reliability and validity of a Persian ATRS. A cross-sectional and prospective cohort study was conducted to translate and cross-culturally adapt the ATRS to Persian language (ATRS-Persian) following steps described in guidelines. Thirty patients with total Achilles tendon rupture and 30 healthy subjects participated in this study. Psychometric properties of floor/ceiling effects (responsiveness), internal consistency reliability, test-retest reliability, standard error of measurement (SEM), smallest detectable change (SDC), construct validity, and discriminant validity were tested. Factor analysis was performed to determine the ATRS-Persian structure. There were no floor or ceiling effects that indicate the content and responsiveness of ATRS-Persian. Internal consistency was high (Cronbach's α 0.95). Item-total correlations exceeded acceptable standard of 0.3 for the all items (0.58-0.95). The test-retest reliability was excellent [(ICC)agreement 0.98]. SEM and SDC were 3.57 and 9.9, respectively. Construct validity was supported by a significant correlation between the ATRS-Persian total score and the Persian Foot and Ankle Outcome Score (PFAOS) total score and PFAOS subscales (r = 0.55-0.83). The ATRS-Persian significantly discriminated between patients and healthy subjects. Explanatory factor analysis revealed 1 component. The ATRS was cross-culturally adapted to Persian and demonstrated to be a reliable and valid instrument to measure functional outcomes in Persian patients with Achilles tendon rupture. II.
Poster - 18: New features in EGSnrc for photon cross sections
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, Elsayed; Mainegra-Hing, Ernesto; Rogers, Davi
2016-08-15
Purpose: To implement two new features in the EGSnrc Monte Carlo system. The first is an option to account for photonuclear attenuation, which can contribute a few percent to the total cross section at the higher end of the energy range of interest to medical physics. The second is an option to use exact NIST XCOM photon cross sections. Methods: For the first feature, the photonuclear total cross sections are generated from the IAEA evaluated data. In the current, first-order implementation, after a photonuclear event, there is no energy deposition or secondary particle generation. The implementation is validated against deterministicmore » calculations and experimental measurements of transmission signals. For the second feature, before this work, if the user explicitly requested XCOM photon cross sections, EGSnrc still used its own internal incoherent scattering cross sections. These differ by up to 2% from XCOM data between 30 keV and 40 MeV. After this work, exact XCOM incoherent scattering cross sections are an available option. Minor interpolation artifacts in pair and triplet XCOM cross sections are also addressed. The default for photon cross section in EGSnrc is XCOM except for the new incoherent scattering cross sections, which have to be explicitly requested. The photonuclear, incoherent, pair and triplet data from this work are available for elements and compounds for photon energies from 1 keV to 100 GeV. Results: Both features are implemented and validated in EGSnrc.Conclusions: The two features are part of the standard EGSnrc distribution as of version 4.2.3.2.« less
Mazzotti, M; Bartoli, I; Castellazzi, G; Marzani, A
2014-09-01
The paper aims at validating a recently proposed Semi Analytical Finite Element (SAFE) formulation coupled with a 2.5D Boundary Element Method (2.5D BEM) for the extraction of dispersion data in immersed waveguides of generic cross-section. To this end, three-dimensional vibroacoustic analyses are carried out on two waveguides of square and rectangular cross-section immersed in water using the commercial Finite Element software Abaqus/Explicit. Real wavenumber and attenuation dispersive data are extracted by means of a modified Matrix Pencil Method. It is demonstrated that the results obtained using the two techniques are in very good agreement. Copyright © 2014 Elsevier B.V. All rights reserved.
Classification based upon gene expression data: bias and precision of error rates.
Wood, Ian A; Visscher, Peter M; Mengersen, Kerrie L
2007-06-01
Gene expression data offer a large number of potentially useful predictors for the classification of tissue samples into classes, such as diseased and non-diseased. The predictive error rate of classifiers can be estimated using methods such as cross-validation. We have investigated issues of interpretation and potential bias in the reporting of error rate estimates. The issues considered here are optimization and selection biases, sampling effects, measures of misclassification rate, baseline error rates, two-level external cross-validation and a novel proposal for detection of bias using the permutation mean. Reporting an optimal estimated error rate incurs an optimization bias. Downward bias of 3-5% was found in an existing study of classification based on gene expression data and may be endemic in similar studies. Using a simulated non-informative dataset and two example datasets from existing studies, we show how bias can be detected through the use of label permutations and avoided using two-level external cross-validation. Some studies avoid optimization bias by using single-level cross-validation and a test set, but error rates can be more accurately estimated via two-level cross-validation. In addition to estimating the simple overall error rate, we recommend reporting class error rates plus where possible the conditional risk incorporating prior class probabilities and a misclassification cost matrix. We also describe baseline error rates derived from three trivial classifiers which ignore the predictors. R code which implements two-level external cross-validation with the PAMR package, experiment code, dataset details and additional figures are freely available for non-commercial use from http://www.maths.qut.edu.au/profiles/wood/permr.jsp
Beckers, Laura; Speth, Lucianne; Rameckers, Eugène; Janssen-Potten, Yvonne
2017-07-01
To produce a Dutch translation of the Lifestyle Assessment Questionnaire for children with cerebral palsy (LAQ-CP), adapted for cross-cultural differences. The translation process consisted of 6 stages, following a guideline for cross-cultural adaptations including duplicate forward- and back-translations, expert group review, pilot-testing, and a process audit. Several adaptations to the questionnaire were required due to cross-cultural differences. As a result of the pilot-test, the layout was adapted to the desires of the users. The process auditor stated that the process had been comprehensive and valued the quality of the work. The project resulted in a Dutch translation of the LAQ-CP, adapted for cross-cultural differences. Validation of the translated questionnaire is required before use in clinical practice and research is recommended (Dutch abstract, Supplemental Digital Content 1, available at: http://links.lww.com/PPT/A164).
González-Sánchez, Manuel; Ruiz-Muñoz, Maria; Li, Guang Zhi; Cuesta-Vargas, Antonio I
2018-08-01
To perform a cross-cultural adaptation and validation of the Foot Function Index (FFI) questionnaire to develop the Chinese version. Three hundred and six patients with foot and ankle neuromusculoskeletal diseases participated in this observational study. Construct validity, internal consistency and criterion validity were calculated for the FFI Chinese version after the translation and transcultural adaptation process. Internal consistency ranged from 0.996 to 0.998. Test-retest analysis ranged from 0.985 to 0.994; minimal detectable change 90: 2.270; standard error of measurement: 0.973. Load distribution of the three factors had an eigenvalue greater than 1. Chi-square value was 9738.14 (p < 0.001). Correlations with the three factors were significant between Factor 1 and the other two: r = -0.634 (Factor 2) and r = -0.191 (Factor 1). Foot Function Index (Taiwan Version), Short-Form 12 (Version 2) and EuroQol-5D were used for criterion validity. Factors 1 and 2 showed significant correlation with 15/16 and 14/16 scales and subscales, respectively. Foot Function Index Chinese version psychometric characteristics were good to excellent. Chinese researchers and clinicians may use this tool for foot and ankle assessment and monitoring. Implications for rehabilitation A cross-cultural adaptation of the FFI has been done from original version to Chinese. Consistent results and satisfactory psychometric properties of the Foot Function Index Chinese version have been reported. For Chinese speaking researcher and clinician FFI-Ch could be used as a tool to assess patients with foot disease.
Cross-Cultural Validation of the Korean Version of the Chalder Fatigue Scale.
Ha, Hyeju; Jeong, Donghee; Hahm, Bong-Jin; Shim, Eun-Jung
2018-06-01
University students are vulnerable to fatigue. If not adequately dealt with, fatigue might develop into various health problems and negatively affect quality of life (QOL). The present study examined psychometric properties of the Korean version of the Chalder Fatigue Scale (K-CFQ) in university students. Data were obtained from two samples of undergraduate students in Korea. The first dataset (N = 557) was collected in a cross-sectional survey in 2015 and the second dataset (N = 338) from a longitudinal survey with three time points over a semester period in 2016. Participants completed measures of fatigue, QOL, depression, anxiety, and sleep quality. Three-factor model (physical fatigue, low energy, and mental fatigue) rather than the original two-factor model (physical and mental fatigue) provided a better goodness of fit indices to the data. Internal consistency of the K-CFQ was satisfactory, with Cronbach's α value of 0.88 for the total scale and those of subscales ranging from 0.73 to 0.87. Its convergent validity was supported by its significant association with anxiety, depression, sleep quality, and QOL. Significant association between T1 K-CFQ with physical QOL at T2 and T3 supported its predictive validity. Its known-group validity was proven with higher K-CFQ scores observed in the participants with depression and those with poor sleep quality. Current results suggest that K-CFQ is a valid and reliable measure of fatigue, and a better model fit of the three-factor structure of the K-CFQ implies potential cross-cultural differences in the dimensionality of fatigue.
Olivera, André Rodrigues; Roesler, Valter; Iochpe, Cirano; Schmidt, Maria Inês; Vigo, Álvaro; Barreto, Sandhi Maria; Duncan, Bruce Bartholow
2017-01-01
Type 2 diabetes is a chronic disease associated with a wide range of serious health complications that have a major impact on overall health. The aims here were to develop and validate predictive models for detecting undiagnosed diabetes using data from the Longitudinal Study of Adult Health (ELSA-Brasil) and to compare the performance of different machine-learning algorithms in this task. Comparison of machine-learning algorithms to develop predictive models using data from ELSA-Brasil. After selecting a subset of 27 candidate variables from the literature, models were built and validated in four sequential steps: (i) parameter tuning with tenfold cross-validation, repeated three times; (ii) automatic variable selection using forward selection, a wrapper strategy with four different machine-learning algorithms and tenfold cross-validation (repeated three times), to evaluate each subset of variables; (iii) error estimation of model parameters with tenfold cross-validation, repeated ten times; and (iv) generalization testing on an independent dataset. The models were created with the following machine-learning algorithms: logistic regression, artificial neural network, naïve Bayes, K-nearest neighbor and random forest. The best models were created using artificial neural networks and logistic regression. -These achieved mean areas under the curve of, respectively, 75.24% and 74.98% in the error estimation step and 74.17% and 74.41% in the generalization testing step. Most of the predictive models produced similar results, and demonstrated the feasibility of identifying individuals with highest probability of having undiagnosed diabetes, through easily-obtained clinical data.
Scaglione, John M.; Mueller, Don E.; Wagner, John C.
2014-12-01
One of the most important remaining challenges associated with expanded implementation of burnup credit in the United States is the validation of depletion and criticality calculations used in the safety evaluation—in particular, the availability and use of applicable measured data to support validation, especially for fission products (FPs). Applicants and regulatory reviewers have been constrained by both a scarcity of data and a lack of clear technical basis or approach for use of the data. In this study, this paper describes a validation approach for commercial spent nuclear fuel (SNF) criticality safety (k eff) evaluations based on best-available data andmore » methods and applies the approach for representative SNF storage and transport configurations/conditions to demonstrate its usage and applicability, as well as to provide reference bias results. The criticality validation approach utilizes not only available laboratory critical experiment (LCE) data from the International Handbook of Evaluated Criticality Safety Benchmark Experiments and the French Haut Taux de Combustion program to support validation of the principal actinides but also calculated sensitivities, nuclear data uncertainties, and limited available FP LCE data to predict and verify individual biases for relevant minor actinides and FPs. The results demonstrate that (a) sufficient critical experiment data exist to adequately validate k eff calculations via conventional validation approaches for the primary actinides, (b) sensitivity-based critical experiment selection is more appropriate for generating accurate application model bias and uncertainty, and (c) calculated sensitivities and nuclear data uncertainties can be used for generating conservative estimates of bias for minor actinides and FPs. Results based on the SCALE 6.1 and the ENDF/B-VII.0 cross-section libraries indicate that a conservative estimate of the bias for the minor actinides and FPs is 1.5% of their worth within the application model. Finally, this paper provides a detailed description of the approach and its technical bases, describes the application of the approach for representative pressurized water reactor and boiling water reactor safety analysis models, and provides reference bias results based on the prerelease SCALE 6.1 code package and ENDF/B-VII nuclear cross-section data.« less
Multivariate Adaptive Regression Splines (Preprint)
1990-08-01
fold cross -validation would take about ten time as long, and MARS is not all that fast to begin with. Friedman has a number of examples showing...standardized mean squared error of prediction (MSEP), the generalized cross validation (GCV), and the number of selected terms (TERMS). In accordance with...and mi= 10 case were almost exclusively spurious cross product terms and terms involving the nuisance variables x6 through xlo. This large number of
Genomic selection across multiple breeding cycles in applied bread wheat breeding.
Michel, Sebastian; Ametz, Christian; Gungor, Huseyin; Epure, Doru; Grausgruber, Heinrich; Löschenberger, Franziska; Buerstmayr, Hermann
2016-06-01
We evaluated genomic selection across five breeding cycles of bread wheat breeding. Bias of within-cycle cross-validation and methods for improving the prediction accuracy were assessed. The prospect of genomic selection has been frequently shown by cross-validation studies using the same genetic material across multiple environments, but studies investigating genomic selection across multiple breeding cycles in applied bread wheat breeding are lacking. We estimated the prediction accuracy of grain yield, protein content and protein yield of 659 inbred lines across five independent breeding cycles and assessed the bias of within-cycle cross-validation. We investigated the influence of outliers on the prediction accuracy and predicted protein yield by its components traits. A high average heritability was estimated for protein content, followed by grain yield and protein yield. The bias of the prediction accuracy using populations from individual cycles using fivefold cross-validation was accordingly substantial for protein yield (17-712 %) and less pronounced for protein content (8-86 %). Cross-validation using the cycles as folds aimed to avoid this bias and reached a maximum prediction accuracy of [Formula: see text] = 0.51 for protein content, [Formula: see text] = 0.38 for grain yield and [Formula: see text] = 0.16 for protein yield. Dropping outlier cycles increased the prediction accuracy of grain yield to [Formula: see text] = 0.41 as estimated by cross-validation, while dropping outlier environments did not have a significant effect on the prediction accuracy. Independent validation suggests, on the other hand, that careful consideration is necessary before an outlier correction is undertaken, which removes lines from the training population. Predicting protein yield by multiplying genomic estimated breeding values of grain yield and protein content raised the prediction accuracy to [Formula: see text] = 0.19 for this derived trait.
Estimation of Particulate Mass and Manganese Exposure Levels among Welders
Hobson, Angela; Seixas, Noah; Sterling, David; Racette, Brad A.
2011-01-01
Background: Welders are frequently exposed to Manganese (Mn), which may increase the risk of neurological impairment. Historical exposure estimates for welding-exposed workers are needed for epidemiological studies evaluating the relationship between welding and neurological or other health outcomes. The objective of this study was to develop and validate a multivariate model to estimate quantitative levels of welding fume exposures based on welding particulate mass and Mn concentrations reported in the published literature. Methods: Articles that described welding particulate and Mn exposures during field welding activities were identified through a comprehensive literature search. Summary measures of exposure and related determinants such as year of sampling, welding process performed, type of ventilation used, degree of enclosure, base metal, and location of sampling filter were extracted from each article. The natural log of the reported arithmetic mean exposure level was used as the dependent variable in model building, while the independent variables included the exposure determinants. Cross-validation was performed to aid in model selection and to evaluate the generalizability of the models. Results: A total of 33 particulate and 27 Mn means were included in the regression analysis. The final model explained 76% of the variability in the mean exposures and included welding process and degree of enclosure as predictors. There was very little change in the explained variability and root mean squared error between the final model and its cross-validation model indicating the final model is robust given the available data. Conclusions: This model may be improved with more detailed exposure determinants; however, the relatively large amount of variance explained by the final model along with the positive generalizability results of the cross-validation increases the confidence that the estimates derived from this model can be used for estimating welder exposures in absence of individual measurement data. PMID:20870928
Development and Validation of Personality Disorder Spectra Scales for the MMPI-2-RF.
Sellbom, Martin; Waugh, Mark H; Hopwood, Christopher J
2018-01-01
The purpose of this study was to develop and validate a set of MMPI-2-RF (Ben-Porath & Tellegen, 2008/2011) personality disorder (PD) spectra scales. These scales could serve the purpose of assisting with DSM-5 PD diagnosis and help link categorical and dimensional conceptions of personality pathology within the MMPI-2-RF. We developed and provided initial validity results for scales corresponding to the 10 PD constructs listed in the DSM-5 using data from student, community, clinical, and correctional samples. Initial validation efforts indicated good support for criterion validity with an external PD measure as well as with dimensional personality traits included in the DSM-5 alternative model for PDs. Construct validity results using psychosocial history and therapists' ratings in a large clinical sample were generally supportive as well. Overall, these brief scales provide clinicians using MMPI-2-RF data with estimates of DSM-5 PD constructs that can support cross-model connections between categorical and dimensional assessment approaches.
Optical-model abrasion cross sections for high-energy heavy ions
NASA Technical Reports Server (NTRS)
Townsend, L. W.
1981-01-01
Within the context of eikonal scattering theory, a generalized optical model potential approximation to the nucleus-nucleus multiple scattering series is used in an abrasion-ablation collision model to predict abrasion cross sections for relativistic projectile heavy ions. Unlike the optical limit of Glauber theory, which cannot be used for very light nuclei, the abrasion formalism is valid for any projectile target combination at any incident kinetic energy for which eikonal scattering theory can be utilized. Results are compared with experimental results and predictions from Glauber theory.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anastasiou, Charalampos; Duhr, Claude; Dulat, Falko
In this study, we compute the gluon fusion Higgs boson cross-section at N 3LO through the second term in the threshold expansion. This calculation constitutes a major milestone towards the full N 3LO cross section. Our result has the best formal accuracy in the threshold expansion currently available, and includes contributions from collinear regions besides subleading corrections from soft and hard regions, as well as certain logarithmically enhanced contributions for general kinematics. We use our results to perform a critical appraisal of the validity of the threshold approximation at N 3LO in perturbative QCD.
Testing alternative ground water models using cross-validation and other methods
Foglia, L.; Mehl, S.W.; Hill, M.C.; Perona, P.; Burlando, P.
2007-01-01
Many methods can be used to test alternative ground water models. Of concern in this work are methods able to (1) rank alternative models (also called model discrimination) and (2) identify observations important to parameter estimates and predictions (equivalent to the purpose served by some types of sensitivity analysis). Some of the measures investigated are computationally efficient; others are computationally demanding. The latter are generally needed to account for model nonlinearity. The efficient model discrimination methods investigated include the information criteria: the corrected Akaike information criterion, Bayesian information criterion, and generalized cross-validation. The efficient sensitivity analysis measures used are dimensionless scaled sensitivity (DSS), composite scaled sensitivity, and parameter correlation coefficient (PCC); the other statistics are DFBETAS, Cook's D, and observation-prediction statistic. Acronyms are explained in the introduction. Cross-validation (CV) is a computationally intensive nonlinear method that is used for both model discrimination and sensitivity analysis. The methods are tested using up to five alternative parsimoniously constructed models of the ground water system of the Maggia Valley in southern Switzerland. The alternative models differ in their representation of hydraulic conductivity. A new method for graphically representing CV and sensitivity analysis results for complex models is presented and used to evaluate the utility of the efficient statistics. The results indicate that for model selection, the information criteria produce similar results at much smaller computational cost than CV. For identifying important observations, the only obviously inferior linear measure is DSS; the poor performance was expected because DSS does not include the effects of parameter correlation and PCC reveals large parameter correlations. ?? 2007 National Ground Water Association.
Chabrera, Carolina; Areal, Joan; Font, Albert; Caro, Mónica; Bonet, Marta; Zabalegui, Adelaida
2015-01-01
The aim of this study is to develop a Spanish version of the Satisfaction With Decision scale (SWDs) and analyse the psychometric properties of validity and reliability. An observational, descriptive study and validation of a tool to measure satisfaction with the decision. Urology, Radiation oncology, and Medical oncology Departments of the Hospital Universitari Germans Trias i Pujol, Institut Català d'Oncologia and the Institut Oncològic del Vallès - Hospital General de Catalunya. A total of 170 participants diagnosed with prostate cancer, and who could read and write in Spanish and gave their informed consent. A translation, back-translation and cross-cultural adaptation to Spanish was performed on the SWDs. The content validity, criterion validity, construct validity and reliability (internal consistency and stability) of the Spanish version were evaluated. The SWDs contains 6 items with 5-item Likert scales. A Spanish version (ESD) was obtained that was linguistically and conceptually equivalent to the original version. Criterion validity, the ESD correlated with "satisfaction with the decision" using a linear analogue scale, was significant (r=0.63, P<.01) for all items. The factorial analysis showed a unique dimension to explain 82.08% of the variance. The ESD showed excellent results in terms of internal consistency (Cronbach alpha=0.95) and good test-retest reliability with intraclass correlation coefficient of 0.711. The ESD is a validated Spanish scale to measure the satisfaction with the decisions taken in health, and demonstrates a correct validity and reliability. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.
Dutch translation and cross-cultural validation of the Adult Social Care Outcomes Toolkit (ASCOT).
van Leeuwen, Karen M; Bosmans, Judith E; Jansen, Aaltje Pd; Rand, Stacey E; Towers, Ann-Marie; Smith, Nick; Razik, Kamilla; Trukeschitz, Birgit; van Tulder, Maurits W; van der Horst, Henriette E; Ostelo, Raymond W
2015-05-13
The Adult Social Care Outcomes Toolkit was developed to measure outcomes of social care in England. In this study, we translated the four level self-completion version (SCT-4) of the ASCOT for use in the Netherlands and performed a cross-cultural validation. The ASCOT SCT-4 was translated into Dutch following international guidelines, including two forward and back translations. The resulting version was pilot tested among frail older adults using think-aloud interviews. Furthermore, using a subsample of the Dutch ACT-study, we investigated test-retest reliability and construct validity and compared response distributions with data from a comparable English study. The pilot tests showed that translated items were in general understood as intended, that most items were reliable, and that the response distributions of the Dutch translation and associations with other measures were comparable to the original English version. Based on the results of the pilot tests, some small modifications and a revision of the Dignity items were proposed for the final translation, which were approved by the ASCOT development team. The complete original English version and the final Dutch translation can be obtained after registration on the ASCOT website ( http://www.pssru.ac.uk/ascot ). This study provides preliminary evidence that the Dutch translation of the ASCOT is valid, reliable and comparable to the original English version. We recommend further research to confirm the validity of the modified Dutch ASCOT translation.
Reiss, Philip T
2015-08-01
The "ten ironic rules for statistical reviewers" presented by Friston (2012) prompted a rebuttal by Lindquist et al. (2013), which was followed by a rejoinder by Friston (2013). A key issue left unresolved in this discussion is the use of cross-validation to test the significance of predictive analyses. This note discusses the role that cross-validation-based and related hypothesis tests have come to play in modern data analyses, in neuroimaging and other fields. It is shown that such tests need not be suboptimal and can fill otherwise-unmet inferential needs. Copyright © 2015 Elsevier Inc. All rights reserved.
Multivariate pattern analysis for MEG: A comparison of dissimilarity measures.
Guggenmos, Matthias; Sterzer, Philipp; Cichy, Radoslaw Martin
2018-06-01
Multivariate pattern analysis (MVPA) methods such as decoding and representational similarity analysis (RSA) are growing rapidly in popularity for the analysis of magnetoencephalography (MEG) data. However, little is known about the relative performance and characteristics of the specific dissimilarity measures used to describe differences between evoked activation patterns. Here we used a multisession MEG data set to qualitatively characterize a range of dissimilarity measures and to quantitatively compare them with respect to decoding accuracy (for decoding) and between-session reliability of representational dissimilarity matrices (for RSA). We tested dissimilarity measures from a range of classifiers (Linear Discriminant Analysis - LDA, Support Vector Machine - SVM, Weighted Robust Distance - WeiRD, Gaussian Naïve Bayes - GNB) and distances (Euclidean distance, Pearson correlation). In addition, we evaluated three key processing choices: 1) preprocessing (noise normalisation, removal of the pattern mean), 2) weighting decoding accuracies by decision values, and 3) computing distances in three different partitioning schemes (non-cross-validated, cross-validated, within-class-corrected). Four main conclusions emerged from our results. First, appropriate multivariate noise normalization substantially improved decoding accuracies and the reliability of dissimilarity measures. Second, LDA, SVM and WeiRD yielded high peak decoding accuracies and nearly identical time courses. Third, while using decoding accuracies for RSA was markedly less reliable than continuous distances, this disadvantage was ameliorated by decision-value-weighting of decoding accuracies. Fourth, the cross-validated Euclidean distance provided unbiased distance estimates and highly replicable representational dissimilarity matrices. Overall, we strongly advise the use of multivariate noise normalisation as a general preprocessing step, recommend LDA, SVM and WeiRD as classifiers for decoding and highlight the cross-validated Euclidean distance as a reliable and unbiased default choice for RSA. Copyright © 2018 Elsevier Inc. All rights reserved.
Sex estimation from measurements of the first rib in a contemporary Polish population.
Kubicka, Anna Maria; Piontek, Janusz
2016-01-01
The aim of this study was to evaluate the accuracy of sex assessment using measurements of the first rib from computed tomography (CT) to develop a discriminant formula. Four discriminant formulae were derived based on CT imaging of the right first rib of 85 female and 91 male Polish patients of known age and sex. In direct discriminant analysis, the first equation consisted of all first rib variables; the second included measurements of the rib body; the third comprised only two measurements of the sternal end of the first rib. The stepwise method selected the four best variables from all measurements. The discriminant function equation was then tested on a cross-validated group consisting of 23 females and 24 males. The direct discriminant analysis showed that sex assessment was possible in 81.5% of cases in the first group and in 91.5% in the cross-validated group when all variables for the first rib were included. The average accuracy for the original group for rib body and sternal end was 80.9 and 67.9%, respectively. The percentages of correctly assigned individuals for the functions based on the rib body and sternal end in the cross-validated group were 76.6 and 85.0%, respectively. Higher average accuracies were obtained for stepwise discriminant analysis: 83.1% for the original group and 91.2% for the cross-validated group. The exterior edge, anterior-posterior of the sternal end, and depth of the arc were the most reliable parameters. Our results suggest that the first rib is dimorphic and that the described method can be used for sex assessment.
The cross-cultural validity of posttraumatic stress disorder: implications for DSM-5.
Hinton, Devon E; Lewis-Fernández, Roberto
2011-09-01
There is considerable debate about the cross-cultural applicability of the posttraumatic stress disorder (PTSD) category as currently specified. Concerns include the possible status of PTSD as a Western culture-bound disorder and the validity of individual items and criteria thresholds. This review examines various types of cross-cultural validity of the PTSD criteria as defined in DSM-IV-TR, and presents options and preliminary recommendations to be considered for DSM-5. Searches were conducted of the mental health literature, particularly since 1994, regarding cultural-, race-, or ethnicity-related factors that might limit the universal applicability of the diagnostic criteria of PTSD in DSM-IV-TR and the possible criteria for DSM-5. Substantial evidence of the cross-cultural validity of PTSD was found. However, evidence of cross-cultural variability in certain areas suggests the need for further research: the relative salience of avoidance/numbing symptoms, the role of the interpretation of trauma-caused symptoms in shaping symptomatology, and the prevalence of somatic symptoms. This review also indicates the need to modify certain criteria, such as the items on distressing dreams and on foreshortened future, to increase their cross-cultural applicability. Text additions are suggested to increase the applicability of the manual across cultural contexts: specifying that cultural syndromes-such as those indicated in the DSM-IV-TR Glossary-may be a prominent part of the trauma response in certain cultures, and that those syndromes may influence PTSD symptom salience and comorbidity. The DSM-IV-TR PTSD category demonstrates various types of validity. Criteria modification and textual clarifications are suggested to further improve its cross-cultural applicability. © 2010 Wiley-Liss, Inc.
Modeling spanwise nonuniformity in the cross-sectional analysis of composite beams
NASA Astrophysics Data System (ADS)
Ho, Jimmy Cheng-Chung
Spanwise nonuniformity effects are modeled in the cross-sectional analysis of beam theory. This modeling adheres to an established numerical framework on cross-sectional analysis of uniform beams with arbitrary cross-sections. This framework is based on two concepts: decomposition of the rotation tensor and the variational-asymptotic method. Allowance of arbitrary materials and geometries in the cross-section is from discretization of the warping field by finite elements. By this approach, dimensional reduction from three-dimensional elasticity is performed rigorously and the sectional strain energy is derived to be asymptotically-correct. Elastic stiffness matrices are derived for inputs into the global beam analysis. Recovery relations for the displacement, stress, and strain fields are also derived with care to be consistent with the energy. Spanwise nonuniformity effects appear in the form of pointwise and sectionwise derivatives, which are approximated by finite differences. The formulation also accounts for the effects of spanwise variations in initial twist and/or curvature. A linearly tapered isotropic strip is analyzed to demonstrate spanwise nonuniformity effects on the cross-sectional analysis. The analysis is performed analytically by the variational-asymptotic method. Results from beam theory are validated against solutions from plane stress elasticity. These results demonstrate that spanwise nonuniformity effects become significant as the rate at which the cross-sections vary increases. The modeling of transverse shear modes of deformation is accomplished by transforming the strain energy into generalized Timoshenko form. Approximations in this transformation procedure from previous works, when applied to uniform beams, are identified. The approximations are not used in the present work so as to retain more accuracy. Comparison of present results with those previously published shows that these approximations sometimes change the results measurably and thus are inappropriate. Static and dynamic results, from the global beam analysis, are calculated to show the differences between using stiffness constants from previous works and the present work. As a form of validation of the transformation procedure, calculations from the global beam analysis of initially twisted isotropic beams from using curvilinear coordinate axes featuring twist are shown to be equivalent to calculations using Cartesian coordinates.
Ko, Jupil; Rosen, Adam B; Brown, Cathleen N
2015-12-01
The Cumberland Ankle Instability Tool (CAIT) is a valid and reliable patient reported outcome used to assess the presence and severity of chronic ankle instability (CAI). The CAIT has been cross-culturally adapted into other languages for use in non-English speaking populations. However, there are no valid questionnaires to assess CAI in individuals who speak Korean. The purpose of this study was to translate, cross-culturally adapt, and validate the CAIT, for use in a Korean-speaking population with CAI. Cross-cultural reliability study. The CAIT was cross-culturally adapted into Korean according to accepted guidelines and renamed the Cumberland Ankle Instability Tool-Korean (CAIT-K). Twenty-three participants (12 males, 11 females) who were bilingual in English and Korean were recruited and completed the original and adapted versions to assess agreement between versions. An additional 168 national level Korean athletes (106 male, 62 females; age = 20.3 ± 1.1 yrs), who participated in ≥ 90 minutes of physical activity per week, completed the final version of the CAIT-K twice within 14 days. Their completed questionnaires were assessed for internal consistency, test-retest reliability, criterion validity, and construct validity. For bilingual participants, intra-class correlation coefficients (ICC2,1) between the CAIT and the CAIT-K for test-retest reliability were 0.95 (SEM=1.83) and 0.96 (SEM=1.50) in right and left limbs, respectively. The Cronbach's alpha coefficients were 0.92 and 0.90 for the CAIT-K in right and left limbs, respectively. For native Korean speakers, the CAIT-K had high internal consistency (Cronbach's α=0.89) and intra-class correlation coefficient (ICC2,1 = 0.94, SEM=1.72), correlation with the physical component score (rho=0.70, p = 0.001) of the Short-Form Health Survey (SF-36), and the Kaiser-Meyer-Olkin score was 0.87. The original CAIT was translated, cross-culturally adapted, and validated from English to Korean. The CAIT-K appears to be valid and reliable and could be useful in assessing the Korean speaking population with CAI.
Correcting for Optimistic Prediction in Small Data Sets
Smith, Gordon C. S.; Seaman, Shaun R.; Wood, Angela M.; Royston, Patrick; White, Ian R.
2014-01-01
The C statistic is a commonly reported measure of screening test performance. Optimistic estimation of the C statistic is a frequent problem because of overfitting of statistical models in small data sets, and methods exist to correct for this issue. However, many studies do not use such methods, and those that do correct for optimism use diverse methods, some of which are known to be biased. We used clinical data sets (United Kingdom Down syndrome screening data from Glasgow (1991–2003), Edinburgh (1999–2003), and Cambridge (1990–2006), as well as Scottish national pregnancy discharge data (2004–2007)) to evaluate different approaches to adjustment for optimism. We found that sample splitting, cross-validation without replication, and leave-1-out cross-validation produced optimism-adjusted estimates of the C statistic that were biased and/or associated with greater absolute error than other available methods. Cross-validation with replication, bootstrapping, and a new method (leave-pair-out cross-validation) all generated unbiased optimism-adjusted estimates of the C statistic and had similar absolute errors in the clinical data set. Larger simulation studies confirmed that all 3 methods performed similarly with 10 or more events per variable, or when the C statistic was 0.9 or greater. However, with lower events per variable or lower C statistics, bootstrapping tended to be optimistic but with lower absolute and mean squared errors than both methods of cross-validation. PMID:24966219
Cross-cultural adaption and validation of the Persian version of the SWAL-QOL.
Tarameshlu, Maryam; Azimi, Amir Reza; Jalaie, Shohreh; Ghelichi, Leila; Ansari, Noureddin Nakhostin
2017-06-01
The aim of this study was to translate and cross-culturally adapt the swallowing quality-of-life questionnaire (SWAL-QOL) to Persian language and to determine validity and reliability of the Persian version of the swallow quality-of-life questionnaire (PSWAL-QOL) in the patients with oropharyngeal dysphagia.The cross-sectional survey was designed to translate and cross-culturally adapt SWAL-QOL to Persian language following steps recommended in guideline. A total of 142 patients with dysphagia (mean age = 56.7 ± 12.22 years) were selected by non-probability consecutive sampling method to evaluate construct validity and internal consistency. Thirty patients with dysphagia were completed the PSWAL-QOL 2 weeks later for test-retest reliability.The PSWAL-QOL was favorably accepted with no missing items. The floor effect was ranged 0% to 21% and ceiling effect was ranged 0% to 16%. The construct validity was established via exploratory factor analysis. Internal consistency was confirmed with Cronbach α >0.7 for all scales except eating duration (α = 0.68). The test-retest reliability was excellent with intraclass correlation coefficient (ICC) ≥0.75 for all scales.The SWAL-QOL was cross-culturally adapted to Persian and demonstrated to be a valid and reliable self-report questionnaire to measure the impact of dysphagia on the quality-of-life in the Persian patients with oropharyngeal dysphagia.
Cross-cultural adaption and validation of the Persian version of the SWAL-QOL
Tarameshlu, Maryam; Azimi, Amir Reza; Jalaie, Shohreh; Ghelichi, Leila; Ansari, Noureddin Nakhostin
2017-01-01
Abstract The aim of this study was to translate and cross-culturally adapt the swallowing quality-of-life questionnaire (SWAL-QOL) to Persian language and to determine validity and reliability of the Persian version of the swallow quality-of-life questionnaire (PSWAL-QOL) in the patients with oropharyngeal dysphagia. The cross-sectional survey was designed to translate and cross-culturally adapt SWAL-QOL to Persian language following steps recommended in guideline. A total of 142 patients with dysphagia (mean age = 56.7 ± 12.22 years) were selected by non-probability consecutive sampling method to evaluate construct validity and internal consistency. Thirty patients with dysphagia were completed the PSWAL-QOL 2 weeks later for test–retest reliability. The PSWAL-QOL was favorably accepted with no missing items. The floor effect was ranged 0% to 21% and ceiling effect was ranged 0% to 16%. The construct validity was established via exploratory factor analysis. Internal consistency was confirmed with Cronbach α >0.7 for all scales except eating duration (α = 0.68). The test–retest reliability was excellent with intraclass correlation coefficient (ICC) ≥0.75 for all scales. The SWAL-QOL was cross-culturally adapted to Persian and demonstrated to be a valid and reliable self-report questionnaire to measure the impact of dysphagia on the quality-of-life in the Persian patients with oropharyngeal dysphagia. PMID:28658118
Certification in Structural Health Monitoring Systems
2011-09-01
validation [3,8]. This may be accomplished by computing the sum of squares of pure error ( SSPE ) and its associated squared correlation [3,8]. To compute...these values, a cross- validation sample must be established. In general, if the SSPE is high, the model does not predict well on independent data...plethora of cross- validation methods, some of which are more useful for certain models than others [3,8]. When possible, a disclosure of the SSPE
Pitchford, Nicola J; Outhwaite, Laura A
2016-01-01
Assessment of cognitive and motor functions is fundamental for developmental and neuropsychological profiling. Assessments are usually conducted on an individual basis, with a trained examiner, using standardized paper and pencil tests, and can take up to an hour or more to complete, depending on the nature of the test. This makes traditional standardized assessments of child development largely unsuitable for use in low-income countries. Touch screen tablets afford the opportunity to assess cognitive functions in groups of participants, with untrained administrators, with precision recording of responses, thus automating the assessment process. In turn, this enables cognitive profiling to be conducted in contexts where access to qualified examiners and standardized assessments are rarely available. As such, touch screen assessments could provide a means of assessing child development in both low- and high-income countries, which would afford cross-cultural comparisons to be made with the same assessment tool. However, before touch screen tablet assessments can be used for cognitive profiling in low-to-high-income countries they need to be shown to provide reliable and valid measures of performance. We report the development of a new touch screen tablet assessment of basic cognitive and motor functions for use with early years primary school children in low- and high-income countries. Measures of spatial intelligence, visual attention, short-term memory, working memory, manual processing speed, and manual coordination are included as well as mathematical knowledge. To investigate if this new touch screen assessment tool can be used for cross-cultural comparisons we administered it to a sample of children ( N = 283) spanning standards 1-3 in a low-income country, Malawi, and a smaller sample of children ( N = 70) from first year of formal schooling from a high-income country, the UK. Split-half reliability, test-retest reliability, face validity, convergent construct validity, predictive criterion validity, and concurrent criterion validity were investigated. Results demonstrate "proof of concept" that touch screen tablet technology can provide reliable and valid psychometric measures of performance in the early years, highlighting its potential to be used in cross-cultural comparisons and research.
Calibration of the Dutch-Flemish PROMIS Pain Behavior item bank in patients with chronic pain.
Crins, M H P; Roorda, L D; Smits, N; de Vet, H C W; Westhovens, R; Cella, D; Cook, K F; Revicki, D; van Leeuwen, J; Boers, M; Dekker, J; Terwee, C B
2016-02-01
The aims of the current study were to calibrate the item parameters of the Dutch-Flemish PROMIS Pain Behavior item bank using a sample of Dutch patients with chronic pain and to evaluate cross-cultural validity between the Dutch-Flemish and the US PROMIS Pain Behavior item banks. Furthermore, reliability and construct validity of the Dutch-Flemish PROMIS Pain Behavior item bank were evaluated. The 39 items in the bank were completed by 1042 Dutch patients with chronic pain. To evaluate unidimensionality, a one-factor confirmatory factor analysis (CFA) was performed. A graded response model (GRM) was used to calibrate the items. To evaluate cross-cultural validity, Differential item functioning (DIF) for language (Dutch vs. English) was evaluated. Reliability of the item bank was also examined and construct validity was studied using several legacy instruments, e.g. the Roland Morris Disability Questionnaire. CFA supported the unidimensionality of the Dutch-Flemish PROMIS Pain Behavior item bank (CFI = 0.960, TLI = 0.958), the data also fit the GRM, and demonstrated good coverage across the pain behavior construct (threshold parameters range: -3.42 to 3.54). Analysis showed good cross-cultural validity (only six DIF items), reliability (Cronbach's α = 0.95) and construct validity (all correlations ≥0.53). The Dutch-Flemish PROMIS Pain Behavior item bank was found to have good cross-cultural validity, reliability and construct validity. The development of the Dutch-Flemish PROMIS Pain Behavior item bank will serve as the basis for Dutch-Flemish PROMIS short forms and computer adaptive testing (CAT). © 2015 European Pain Federation - EFIC®
Comparative assessment of three standardized robotic surgery training methods.
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.
Validation of the Economic and Health Outcomes Model of Type 2 Diabetes Mellitus (ECHO-T2DM).
Willis, Michael; Johansen, Pierre; Nilsson, Andreas; Asseburg, Christian
2017-03-01
The Economic and Health Outcomes Model of Type 2 Diabetes Mellitus (ECHO-T2DM) was developed to address study questions pertaining to the cost-effectiveness of treatment alternatives in the care of patients with type 2 diabetes mellitus (T2DM). Naturally, the usefulness of a model is determined by the accuracy of its predictions. A previous version of ECHO-T2DM was validated against actual trial outcomes and the model predictions were generally accurate. However, there have been recent upgrades to the model, which modify model predictions and necessitate an update of the validation exercises. The objectives of this study were to extend the methods available for evaluating model validity, to conduct a formal model validation of ECHO-T2DM (version 2.3.0) in accordance with the principles espoused by the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) and the Society for Medical Decision Making (SMDM), and secondarily to evaluate the relative accuracy of four sets of macrovascular risk equations included in ECHO-T2DM. We followed the ISPOR/SMDM guidelines on model validation, evaluating face validity, verification, cross-validation, and external validation. Model verification involved 297 'stress tests', in which specific model inputs were modified systematically to ascertain correct model implementation. Cross-validation consisted of a comparison between ECHO-T2DM predictions and those of the seminal National Institutes of Health model. In external validation, study characteristics were entered into ECHO-T2DM to replicate the clinical results of 12 studies (including 17 patient populations), and model predictions were compared to observed values using established statistical techniques as well as measures of average prediction error, separately for the four sets of macrovascular risk equations supported in ECHO-T2DM. Sub-group analyses were conducted for dependent vs. independent outcomes and for microvascular vs. macrovascular vs. mortality endpoints. All stress tests were passed. ECHO-T2DM replicated the National Institutes of Health cost-effectiveness application with numerically similar results. In external validation of ECHO-T2DM, model predictions agreed well with observed clinical outcomes. For all sets of macrovascular risk equations, the results were close to the intercept and slope coefficients corresponding to a perfect match, resulting in high R 2 and failure to reject concordance using an F test. The results were similar for sub-groups of dependent and independent validation, with some degree of under-prediction of macrovascular events. ECHO-T2DM continues to match health outcomes in clinical trials in T2DM, with prediction accuracy similar to other leading models of T2DM.
Attrition from an Adolescent Addiction Treatment Program: A Cross Validation.
ERIC Educational Resources Information Center
Mathisen, Kenneth S.; Meyers, Kathleen
Treatment attrition is a major problem for programs treating adolescent substance abusers. To isolate and cross validate factors which are predictive of addiction treatment attrition among adolescent substance abusers, screening interview and diagnostic variables from 119 adolescent in-patients were submitted to a discriminant equation analysis.…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-23
... Proposed Rule Change To Eliminate the Validated Cross Trade Entry Functionality December 16, 2010. Pursuant... eliminate the Validated Cross Trade Entry Functionality for Exchange-registered Institutional Brokers. The... Brokers (``Institutional Brokers'') by eliminating the ability of an Institutional Broker to execute...
Cross-Cultural Validation of TEMAS, a Minority Projective Test.
ERIC Educational Resources Information Center
Costantino, Giuseppe; And Others
The theoretical framework and cross-cultural validation of Tell-Me-A-Story (TEMAS), a projective test developed to measure personality development in ethnic minority children, is presented. The TEMAS test consists of 23 chromatic pictures which incorporate the following characteristics: (1) representation of antithetical concepts which the…
Freitas, N O; Forero, C G; Alonso, J; Caltran, M P; Dantas, R A S; Farina, J A; Rossi, L A
2017-01-01
Burn patients may encounter social barriers and stigmatization. The objectives of this study were to adapt the Social Comfort Questionnaire (SCQ) into Brazilian Portuguese and to assess the psychometric properties of the adapted version. Cross-cultural adaptation of the 8 items of the SCQ followed international guidelines. We interviewed 240 burn patients and verified the SCQ internal consistency, test-retest reliability and construct validity, correlating the scores with depression [Beck Depression Inventory (BDI)], affect/body image and interpersonal relationships [Burns Specific Health Scale-Revised (BSHS-R)] and self-esteem [Rosenberg's Self-Esteem Scale (RSES)]. We also performed a confirmatory factor analysis (CFA). The cross-cultural adaptation resulted in minor semantic modifications to the original SCQ version. After CFA, a reduced 6-item version showed satisfactory fit to the one-factor model (RMSEA = 0.05, CFI = 0.99, TLI = 0.99). Cronbach alpha's was 0.80, and test-retest intraclass correlation coefficient was 0.86. The final version presented a strong negative correlation with depression (BDI), and strong positive correlations with affect/body image (BSHS-R), interpersonal relationships (BSHS-R) and self-esteem (RSES) (all p < 0.001). The results showed that the SCQ Brazilian Portuguese adapted version complies with the validity and reliability criteria required for an instrument assessing social comfort in Brazilian burn patients. The Brazilian version yields a single score that is easy to interpret and well understood by patients.
NASA Technical Reports Server (NTRS)
Simanonok, K.; Mosely, E.; Charles, J.
1992-01-01
Nine preflight variables related to fluid, electrolyte, and cardiovascular status from 64 first-time Shuttle crewmembers were differentially weighted by discrimination analysis to predict the incidence and severity of each crewmember's space sickness as rated by NASA flight surgeons. The nine variables are serum uric acid, red cell count, environmental temperature at the launch site, serum phosphate, urine osmolality, serum thyroxine, sitting systolic blood pressure, calculated blood volume, and serum chloride. Using two methods of cross-validation on the original samples (jackknife and a stratefied random subsample), these variables enable the prediction of space sickness incidence (NONE or SICK) with 80 percent sickness and space severity (NONE, MILD, MODERATE, of SEVERE) with 59 percent success by one method of cross-validation and 67 percent by another method. Addition of a tenth variable, hours spent in the Weightlessness Environment Training Facility (WETF) did not improve the prediction of space sickness incidences but did improve the prediction of space sickness severity to 66 percent success by the first method of cross-validation of original samples and to 71 percent by the second method. Results to date suggest the presence of predisposing physiologic factors to space sickness that implicate fluid shift etiology. The data also suggest that prior exposure to fluid shift during WETF training may produce some circulatory pre-adaption to fluid shifts in weightlessness that results in a reduction of space sickness severity.
Genome-based prediction of test cross performance in two subsequent breeding cycles.
Hofheinz, Nina; Borchardt, Dietrich; Weissleder, Knuth; Frisch, Matthias
2012-12-01
Genome-based prediction of genetic values is expected to overcome shortcomings that limit the application of QTL mapping and marker-assisted selection in plant breeding. Our goal was to study the genome-based prediction of test cross performance with genetic effects that were estimated using genotypes from the preceding breeding cycle. In particular, our objectives were to employ a ridge regression approach that approximates best linear unbiased prediction of genetic effects, compare cross validation with validation using genetic material of the subsequent breeding cycle, and investigate the prospects of genome-based prediction in sugar beet breeding. We focused on the traits sugar content and standard molasses loss (ML) and used a set of 310 sugar beet lines to estimate genetic effects at 384 SNP markers. In cross validation, correlations >0.8 between observed and predicted test cross performance were observed for both traits. However, in validation with 56 lines from the next breeding cycle, a correlation of 0.8 could only be observed for sugar content, for standard ML the correlation reduced to 0.4. We found that ridge regression based on preliminary estimates of the heritability provided a very good approximation of best linear unbiased prediction and was not accompanied with a loss in prediction accuracy. We conclude that prediction accuracy assessed with cross validation within one cycle of a breeding program can not be used as an indicator for the accuracy of predicting lines of the next cycle. Prediction of lines of the next cycle seems promising for traits with high heritabilities.
Lima, Elaine; Teixeira-Salmela, Luci F; Simões, Luan; Guerra, Ana C C; Lemos, Andrea
2016-03-15
While there are several instruments in Brazil that measure motor function in patients after stroke, it is unknown whether the measurement properties of these instruments are appropriate. To identify the motor function instruments available in Brazil for patients after stroke. To assess the methodological quality of the studies and the results related to the measurement properties of these instruments. Two independent reviewers conducted searches on PubMed, LILACS, CINAHL, Web of Science, and Scopus. Studies that aimed to cross-culturally adapt an existing instrument or create a Brazilian instrument and test at least one measurement property related to motor function in patients after stroke were included. The methodological quality of these studies was checked by the COSMIN checklist with 4-point rating scale and the results of the measurement properties were analyzed by the criteria developed by Terwee et al. A total of 11 instruments were considered eligible, none of which were created in Brazil. The process of cross-cultural adaptation was inadequate in 10 out of 11 instruments due to the lack of back-translation or due to inappropriate target population. All of the instruments presented flaws in the measurement properties, especially reliability, internal consistency, and construct validity. The flaws observed in both cross-cultural adaptation process and testing measurement properties make the results inconclusive on the validity of the available instruments. Adequate procedures of cross-cultural adaptation and measurement properties of these instruments are strongly needed.
Measurement invariance of the Belief in a Zero-Sum Game scale across 36 countries.
Różycka-Tran, Joanna; Jurek, Paweł; Olech, Michał; Piotrowski, Jarosław; Żemojtel-Piotrowska, Magdalena
2017-11-28
In this paper, we examined the psychometric properties of cross-cultural validation and replicability (i.e. measurement invariance) of the Belief in a Zero-Sum Game (BZSG) scale, measuring antagonistic belief about interpersonal relations over scarce resources. The factorial structure of the BZSG scale was investigated in student samples from 36 countries (N = 9907), using separate confirmatory factor analyses (CFAs) for each country. The cross-cultural validation of the scale was based on multigroup confirmatory factor analyses (MGCFA). The results confirmed that the scale had a one-factor structure in all countries, in which configural and metric invariance between countries was confirmed. As a zero-sum belief about social relations perceived as antagonistic, BZSG is an important factor related to, for example, social and international relations, attitudes toward immigrants, or well-being. The paper proposes different uses of the BZSG scale for cross-cultural studies in different fields of psychology: social, political, or economic. © 2017 International Union of Psychological Science.
Validating the psycholinguistic aspects of LITMUS-CLT: Evidence from Polish and Norwegian.
Hansen, Pernille; Simonsen, Hanne Gram; Łuniewska, Magdalena; Haman, Ewa
2017-01-01
The novel assessment tool Cross-Linguistic Lexical Tasks (LITMUS-CLT) aims for comparable cross-linguistic assessment of multilingual children's lexical skills by basing each language version on two language-specific variables: age of acquisition (AoA) and complexity index (CI), a novel measure related to phonology, morphology, exposure and etymology. This article investigates the validity of this methodology, asking whether the underlying properties are robust predictors of children's performance. The Polish and Norwegian CLTs were used to assess 32 bilingual Polish-Norwegian, 34 monolingual Norwegian and 36 monolingual Polish children. The effects of AoA and CI were contrasted with frequency in child directed speech (CDS) and imageability, two known predictors of lexical development. AoA was a reliable predictor of performance within all parts of CLT, in contrast to CI. Apart from AoA, only exposure and CDS frequency had a significant effect within both monolinguals and bilinguals. These results indicate that CLT assesses lexical skills in a cross-linguistically comparable manner, but suggest a revision of the CI measure.
New Parameterization of Neutron Absorption Cross Sections
NASA Technical Reports Server (NTRS)
Tripathi, Ram K.; Wilson, John W.; Cucinotta, Francis A.
1997-01-01
Recent parameterization of absorption cross sections for any system of charged ion collisions, including proton-nucleus collisions, is extended for neutron-nucleus collisions valid from approx. 1 MeV to a few GeV, thus providing a comprehensive picture of absorption cross sections for any system of collision pairs (charged or uncharged). The parameters are associated with the physics of the problem. At lower energies, optical potential at the surface is important, and the Pauli operator plays an increasingly important role at intermediate energies. The agreement between the calculated and experimental data is better than earlier published results.
Initial Retrieval Validation from the Joint Airborne IASI Validation Experiment (JAIVEx)
NASA Technical Reports Server (NTRS)
Zhou, Daniel K.; Liu, Xu; Smith, WIlliam L.; Larar, Allen M.; Taylor, Jonathan P.; Revercomb, Henry E.; Mango, Stephen A.; Schluessel, Peter; Calbet, Xavier
2007-01-01
The Joint Airborne IASI Validation Experiment (JAIVEx) was conducted during April 2007 mainly for validation of the Infrared Atmospheric Sounding Interferometer (IASI) on the MetOp satellite, but also included a strong component focusing on validation of the Atmospheric InfraRed Sounder (AIRS) aboard the AQUA satellite. The cross validation of IASI and AIRS is important for the joint use of their data in the global Numerical Weather Prediction process. Initial inter-comparisons of geophysical products have been conducted from different aspects, such as using different measurements from airborne ultraspectral Fourier transform spectrometers (specifically, the NPOESS Airborne Sounder Testbed Interferometer (NAST-I) and the Scanning-High resolution Interferometer Sounder (S-HIS) aboard the NASA WB-57 aircraft), UK Facility for Airborne Atmospheric Measurements (FAAM) BAe146-301 aircraft insitu instruments, dedicated dropsondes, radiosondes, and ground based Raman Lidar. An overview of the JAIVEx retrieval validation plan and some initial results of this field campaign are presented.
Body shape indices are predictors for estimating fat-free mass in male athletes
Aoki, Toru; Komori, Daisuke; Oyamada, Kazuyuki; Murata, Kensuke; Fujita, Eiji; Akamine, Takuya; Urita, Yoshihisa; Yamamoto, Masayoshi
2018-01-01
It is unknown whether body size and body shape parameters can be predictors for estimating whole body fat-free mass (FFM) in male athletes. This study aimed to investigate whether body size and shape variables can be predictors for FFM in male athletes. Using a whole-body dual-energy X-ray absorptiometry scanner, whole body fat mass (FM) and FFM were determined in 132 male athletes and 14 sedentary males. The sample was divided into two groups: validation (N = 98) and cross-validation (N = 48) groups. Body height (BH), body mass (BM), and waist circumference at immediately above the iliac crest (W) were measured. BM-to-W and W-to-BH ratios were calculated as indices of body shapes. Stepwise multiple regression analysis revealed that BM/W and W/BH were selected as explainable variables for predicting FFM. The equation developed in the validation group was FFM (kg) = 0.883 × BM/W (kg/m) + 43.674 × W/BH (cm/cm)– 41.480 [R2 = 0.900, SEE (%SEE) = 2.3 kg (3.8%)], which was validated in the cross-validation group. Thus, the current results demonstrate that an equation using BM/W and W/BH as independent variables is applicable for predicting FFM in male athletes. PMID:29346452
Kim, Kyoung-Eun; Lim, Jae-Young
2011-01-01
The Roland-Morris Disability Questionnaire (RMDQ) is a reliable tool for evaluating disability in patients with back pain, but no Korean version has been published and validated. We developed a cross-culturally adapted Korean version of the RMDQ (RMDQ-K) and validated its use for assessing disability in Korean patients with low back pain. Two hundred thirty-one patients with low back pain were assessed using the RMDQ-K, visual analog scale (VAS) during rest and activity, and the Oswestry Disability Index (ODI). The results of 40 patients were used to evaluate the test-retest reliability. The correlations of the RMDQ-K with the VAS and ODI were used to assess validity. The reliability of the RMDQ-K estimated using the internal consistency reached a Cronbach's alpha of 0.893. Test-retest trials showed a high intraclass correlation coefficient of 0.837 (95% CI 0.833-0.953). The RMDQ-K was significantly correlated with the ODI (r=0.738) and VAS during rest (r=0.450) and activity (r=0.412). This study demonstrates that the RMDQ-K is a reliable, valid instrument for measuring of disability in Korean patients with low back pain.
Application of Monte Carlo cross-validation to identify pathway cross-talk in neonatal sepsis.
Zhang, Yuxia; Liu, Cui; Wang, Jingna; Li, Xingxia
2018-03-01
To explore genetic pathway cross-talk in neonates with sepsis, an integrated approach was used in this paper. To explore the potential relationships between differently expressed genes between normal uninfected neonates and neonates with sepsis and pathways, genetic profiling and biologic signaling pathway were first integrated. For different pathways, the score was obtained based upon the genetic expression by quantitatively analyzing the pathway cross-talk. The paired pathways with high cross-talk were identified by random forest classification. The purpose of the work was to find the best pairs of pathways able to discriminate sepsis samples versus normal samples. The results found 10 pairs of pathways, which were probably able to discriminate neonates with sepsis versus normal uninfected neonates. Among them, the best two paired pathways were identified according to analysis of extensive literature. Impact statement To find the best pairs of pathways able to discriminate sepsis samples versus normal samples, an RF classifier, the DS obtained by DEGs of paired pathways significantly associated, and Monte Carlo cross-validation were applied in this paper. Ten pairs of pathways were probably able to discriminate neonates with sepsis versus normal uninfected neonates. Among them, the best two paired pathways ((7) IL-6 Signaling and Phospholipase C Signaling (PLC); (8) Glucocorticoid Receptor (GR) Signaling and Dendritic Cell Maturation) were identified according to analysis of extensive literature.
Revealing interaction mode between HIV-1 protease and mannitol analog inhibitor.
Yan, Guan-Wen; Chen, Yue; Li, Yixue; Chen, Hai-Feng
2012-06-01
HIV protease is a key enzyme to play a key role in the HIV-1 replication cycle and control the maturation from HIV viruses to an infectious virion. HIV-1 protease has become an important target for anti-HIV-1 drug development. Here, we used molecular dynamics simulation to study the binding mode between mannitol derivatives and HIV-1 protease. The results suggest that the most active compound (M35) has more stable hydrogen bonds and stable native contacts than the less active one (M17). These mannitol derivatives might have similar interaction mode with HIV-1 protease. Then, 3D-QSAR was used to construct quantitative structure-activity models. The cross-validated q(2) values are found as 0.728 and 0.611 for CoMFA and CoMSIA, respectively. And the non-cross-validated r(2) values are 0.973 and 0.950. Nine test set compounds validate the model. The results show that this model possesses better prediction ability than the previous work. This model can be used to design new chemical entities and make quantitative prediction of the bioactivities for HIV-1 protease inhibitors before resorting to in vitro and in vivo experiment. © 2012 John Wiley & Sons A/S.
Riaz, Qaiser; Vögele, Anna; Krüger, Björn; Weber, Andreas
2015-01-01
A number of previous works have shown that information about a subject is encoded in sparse kinematic information, such as the one revealed by so-called point light walkers. With the work at hand, we extend these results to classifications of soft biometrics from inertial sensor recordings at a single body location from a single step. We recorded accelerations and angular velocities of 26 subjects using integrated measurement units (IMUs) attached at four locations (chest, lower back, right wrist and left ankle) when performing standardized gait tasks. The collected data were segmented into individual walking steps. We trained random forest classifiers in order to estimate soft biometrics (gender, age and height). We applied two different validation methods to the process, 10-fold cross-validation and subject-wise cross-validation. For all three classification tasks, we achieve high accuracy values for all four sensor locations. From these results, we can conclude that the data of a single walking step (6D: accelerations and angular velocities) allow for a robust estimation of the gender, height and age of a person. PMID:26703601
Psychiatric diagnosis - is it universal or relative to culture?
Canino, Glorisa; Alegría, Margarita
2008-03-01
There is little consensus on the extent to which psychiatric disorders or syndromes are universal or the extent to which they differ on their core definitions and constellation of symptoms as a result of cultural or contextual factors. This controversy continues due to the lack of biological markers, imprecise measurement and the lack of a gold standard for validating most psychiatric conditions. Empirical studies were used to present evidence in favor of or against a universalist or relativistic view of child psychiatric disorders using a model developed by Robins and Guze to determine the validity of psychiatric disorders. The prevalence of some of the most common specific disorders and syndromes as well as its risk and protective factors vary across cultures, yet comorbid patterns and response to treatments vary little across cultures. Cross-cultural longitudinal data on outcomes is equivocal. The cross-cultural validity of child disorders may vary drastically depending on the disorder, but empirical evidence that attests for the cross-cultural validity of diagnostic criteria for each child disorder is lacking. There is a need for studies that investigate the extent to which gene-environment interactions are related to specific disorders across cultures. Clinicians are urged to consider culture and context in determining the way in which children's psychopathology may be manifested independent of their views. Recommendations for the upcoming classificatory system are provided so that practical or theoretical considerations are addressed about how culture and ethnic issues affect the assessment or treatment of specific disorders in children.
Development of a Bayesian model to estimate health care outcomes in the severely wounded
Stojadinovic, Alexander; Eberhardt, John; Brown, Trevor S; Hawksworth, Jason S; Gage, Frederick; Tadaki, Douglas K; Forsberg, Jonathan A; Davis, Thomas A; Potter, Benjamin K; Dunne, James R; Elster, E A
2010-01-01
Background: Graphical probabilistic models have the ability to provide insights as to how clinical factors are conditionally related. These models can be used to help us understand factors influencing health care outcomes and resource utilization, and to estimate morbidity and clinical outcomes in trauma patient populations. Study design: Thirty-two combat casualties with severe extremity injuries enrolled in a prospective observational study were analyzed using step-wise machine-learned Bayesian belief network (BBN) and step-wise logistic regression (LR). Models were evaluated using 10-fold cross-validation to calculate area-under-the-curve (AUC) from receiver operating characteristics (ROC) curves. Results: Our BBN showed important associations between various factors in our data set that could not be developed using standard regression methods. Cross-validated ROC curve analysis showed that our BBN model was a robust representation of our data domain and that LR models trained on these findings were also robust: hospital-acquired infection (AUC: LR, 0.81; BBN, 0.79), intensive care unit length of stay (AUC: LR, 0.97; BBN, 0.81), and wound healing (AUC: LR, 0.91; BBN, 0.72) showed strong AUC. Conclusions: A BBN model can effectively represent clinical outcomes and biomarkers in patients hospitalized after severe wounding, and is confirmed by 10-fold cross-validation and further confirmed through logistic regression modeling. The method warrants further development and independent validation in other, more diverse patient populations. PMID:21197361
Cross-modal face recognition using multi-matcher face scores
NASA Astrophysics Data System (ADS)
Zheng, Yufeng; Blasch, Erik
2015-05-01
The performance of face recognition can be improved using information fusion of multimodal images and/or multiple algorithms. When multimodal face images are available, cross-modal recognition is meaningful for security and surveillance applications. For example, a probe face is a thermal image (especially at nighttime), while only visible face images are available in the gallery database. Matching a thermal probe face onto the visible gallery faces requires crossmodal matching approaches. A few such studies were implemented in facial feature space with medium recognition performance. In this paper, we propose a cross-modal recognition approach, where multimodal faces are cross-matched in feature space and the recognition performance is enhanced with stereo fusion at image, feature and/or score level. In the proposed scenario, there are two cameras for stereo imaging, two face imagers (visible and thermal images) in each camera, and three recognition algorithms (circular Gaussian filter, face pattern byte, linear discriminant analysis). A score vector is formed with three cross-matched face scores from the aforementioned three algorithms. A classifier (e.g., k-nearest neighbor, support vector machine, binomial logical regression [BLR]) is trained then tested with the score vectors by using 10-fold cross validations. The proposed approach was validated with a multispectral stereo face dataset from 105 subjects. Our experiments show very promising results: ACR (accuracy rate) = 97.84%, FAR (false accept rate) = 0.84% when cross-matching the fused thermal faces onto the fused visible faces by using three face scores and the BLR classifier.
Li, Shun-Lai; He, Mao-Yu; Du, Hong-Guang
2011-01-01
The active metabolite of the novel immunosuppressive agent leflunomide has been shown to inhibit the enzyme dihydroorotate dehydrogenase (DHODH). This enzyme catalyzes the fourth step in de novo pyrimidine biosynthesis. Self-organizing molecular field analysis (SOMFA), a simple three-dimensional quantitative structure-activity relationship (3D-QSAR) method is used to study the correlation between the molecular properties and the biological activities of a series of analogues of the active metabolite. The statistical results, cross-validated rCV2 (0.664) and non cross-validated r2 (0.687), show a good predictive ability. The final SOMFA model provides a better understanding of DHODH inhibitor-enzyme interactions, and may be useful for further modification and improvement of inhibitors of this important enzyme. PMID:21686163
Multisample cross-validation of a model of childhood posttraumatic stress disorder symptomatology.
Anthony, Jason L; Lonigan, Christopher J; Vernberg, Eric M; Greca, Annette M La; Silverman, Wendy K; Prinstein, Mitchell J
2005-12-01
This study is the latest advancement of our research aimed at best characterizing children's posttraumatic stress reactions. In a previous study, we compared existing nosologic and empirical models of PTSD dimensionality and determined the superior model was a hierarchical one with three symptom clusters (Intrusion/Active Avoidance, Numbing/Passive Avoidance, and Arousal; Anthony, Lonigan, & Hecht, 1999). In this study, we cross-validate this model in two populations. Participants were 396 fifth graders who were exposed to either Hurricane Andrew or Hurricane Hugo. Multisample confirmatory factor analysis demonstrated the model's factorial invariance across populations who experienced traumatic events that differed in severity. These results show the model's robustness to characterize children's posttraumatic stress reactions. Implications for diagnosis, classification criteria, and an empirically supported theory of PTSD are discussed.
Zahoor, Hafiz; Chan, Albert P. C.; Utama, Wahyudi P.; Gao, Ran; Zafar, Irfan
2017-01-01
This study attempts to validate a safety performance (SP) measurement model in the cross-cultural setting of a developing country. In addition, it highlights the variations in investigating the relationship between safety climate (SC) factors and SP indicators. The data were collected from forty under-construction multi-storey building projects in Pakistan. Based on the results of exploratory factor analysis, a SP measurement model was hypothesized. It was tested and validated by conducting confirmatory factor analysis on calibration and validation sub-samples respectively. The study confirmed the significant positive impact of SC on safety compliance and safety participation, and negative impact on number of self-reported accidents/injuries. However, number of near-misses could not be retained in the final SP model because it attained a lower standardized path coefficient value. Moreover, instead of safety participation, safety compliance established a stronger impact on SP. The study uncovered safety enforcement and promotion as a novel SC factor, whereas safety rules and work practices was identified as the most neglected factor. The study contributed to the body of knowledge by unveiling the deviations in existing dimensions of SC and SP. The refined model is expected to concisely measure the SP in the Pakistani construction industry, however, caution must be exercised while generalizing the study results to other developing countries. PMID:28350366
Zahoor, Hafiz; Chan, Albert P C; Utama, Wahyudi P; Gao, Ran; Zafar, Irfan
2017-03-28
This study attempts to validate a safety performance (SP) measurement model in the cross-cultural setting of a developing country. In addition, it highlights the variations in investigating the relationship between safety climate (SC) factors and SP indicators. The data were collected from forty under-construction multi-storey building projects in Pakistan. Based on the results of exploratory factor analysis, a SP measurement model was hypothesized. It was tested and validated by conducting confirmatory factor analysis on calibration and validation sub-samples respectively. The study confirmed the significant positive impact of SC on safety compliance and safety participation , and negative impact on number of self-reported accidents/injuries . However, number of near-misses could not be retained in the final SP model because it attained a lower standardized path coefficient value. Moreover, instead of safety participation , safety compliance established a stronger impact on SP. The study uncovered safety enforcement and promotion as a novel SC factor, whereas safety rules and work practices was identified as the most neglected factor. The study contributed to the body of knowledge by unveiling the deviations in existing dimensions of SC and SP. The refined model is expected to concisely measure the SP in the Pakistani construction industry, however, caution must be exercised while generalizing the study results to other developing countries.
ERIC Educational Resources Information Center
Akinpelu, Aderonke O.; Odetunde, Marufat O.; Odole, Adesola C.
2012-01-01
Stroke-Specific Quality of Life 2.0 (SS-QoL 2.0) scale is used widely and has been cross-culturally adapted to many languages. This study aimed at the cross-cultural adaptation of SS-QoL 2.0 to Yoruba, the indigenous language of south-western Nigeria, and to carry out an initial investigation on its validity. English SS-QoL 2.0 was first adapted…
Development of the Persian version of the Vertigo Symptom Scale: Validity and reliability
Kamalvand, Atefeh; Ghahraman, Mansoureh Adel; Jalaie, Shohreh
2017-01-01
Background: Vertigo Symptom Scale (VSS) is a proper instrument for assessing the patient status, clarifying the symptoms, and examining the relative impact of the vertigo and anxiety on reported handicap. Our aim is the translation and cross-cultural adaptation of the VSS into Persian language (VSS-P) and investigating its validity and reliability in patients with peripheral vestibular disorders. Materials and Methods: VSS was translated into Persian. Cross-cultural adaptation was carried out on 101 patients with peripheral vestibular disorders and 34 participants with no history of vertigo. They completed the Persian versions of VSS, dizziness handicap inventory (DHI), and Beck anxiety inventory (BAI). Internal, discriminant, and convergent validities, internal consistency, and test-retest reliability were determined. Results: The VSS-P showed good face validity. Internal validity was confirmed and demonstrated the presence of two vertigo (VSS-VER) and autonomic-anxiety (VSS-AA) subscales. Significant difference between the median scores for patient and healthy groups was reported in discriminate validity (P <0.001). Convergent validity revealed high correlation between both BAI and DHI with VSS-P. There was a high test-retest reliability; with intraclass correlation coefficient of 0.89, 0.86, and 0.91 for VSS-AA, VER, and VSS-P, respectively. The internal consistency was good with Cronbach's alpha 0.90 for VER subscale, 0.86 for VSS-AA subscale, and 0.92 for the overall VSS-P. Conclusion: The Persian version of the VSS could be used clinically as a valid and reliable tool. Thus, it is a key instrument to focus on the symptoms associated with dizziness. PMID:28616045
Sharma, Ram C; Hara, Keitarou; Hirayama, Hidetake
2017-01-01
This paper presents the performance and evaluation of a number of machine learning classifiers for the discrimination between the vegetation physiognomic classes using the satellite based time-series of the surface reflectance data. Discrimination of six vegetation physiognomic classes, Evergreen Coniferous Forest, Evergreen Broadleaf Forest, Deciduous Coniferous Forest, Deciduous Broadleaf Forest, Shrubs, and Herbs, was dealt with in the research. Rich-feature data were prepared from time-series of the satellite data for the discrimination and cross-validation of the vegetation physiognomic types using machine learning approach. A set of machine learning experiments comprised of a number of supervised classifiers with different model parameters was conducted to assess how the discrimination of vegetation physiognomic classes varies with classifiers, input features, and ground truth data size. The performance of each experiment was evaluated by using the 10-fold cross-validation method. Experiment using the Random Forests classifier provided highest overall accuracy (0.81) and kappa coefficient (0.78). However, accuracy metrics did not vary much with experiments. Accuracy metrics were found to be very sensitive to input features and size of ground truth data. The results obtained in the research are expected to be useful for improving the vegetation physiognomic mapping in Japan.
Cid, Luis; Lettnin, Carla; Stobäus, Claus; Monteiro, Diogo; Davoglio, Tárcia; Moutão, João
2016-02-19
The main propose of this study is the cross-cultural validation of the Basic Psychological Needs in Physical Education Scale among Portugal and Brazil samples, through the study of measurement model invariance. Participated in this study, two independent samples, one with 616 Portuguese students, of the 2nd and 3rd basic grade of public school, aged between 9 and 18 years old and another with 450 Brazilian students, from 1st, 2nd and 3rd middle grade of public and private school, aged between 14 and 18 years old. The results support the suitability of the model (three factors, each one with four items), showing an adequate fit to the data in each sample (Portugal: χ2 = 203.8, p = .001, df = 51, SRMR = .062, NNFI = .926, CFI = .943, RMSEA = .070, RMSEA 90% IC = .060-.080; Brazil: χ2 = 173.7, p = .001, df = 51, SRMR = .052, NNFI = .940, CFI = .954, RMSEA = .073, RMSEA 90% IC = .061-.085), as well valid cross-cultural invariance among Portuguese e Brazilian samples (∆CFI ≤ .01). Those findings allow us to conclude that scale can be used to measure the basic psychological needs in physical education in Portugal and in Brazil.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tommasi, J.; Ruggieri, J. M.; Lebrat, J. F.
The latest release (2.1) of the ERANOS code system, using JEF-2.2, JEFF-3.1 and ENDF/B-VI r8 multigroup cross-section libraries is currently being validated on fast reactor critical experiments at CEA-Cadarache (France). This paper briefly presents the library effect studies and the detailed best-estimate validation studies performed up to now as part of the validation process. The library effect studies are performed over a wide range of experimental configurations, using simple model and method options. They yield global trends about the shift from JEF-2.2 to JEFF-3.1 cross-section libraries, that can be related to individual sensitivities and cross-section changes. The more detailed, best-estimate,more » calculations have been performed up to now over three experimental configurations carried out in the MASURCA critical facility at CEA-Cadarache: two cores with a softened spectrum due to large amounts of graphite (MAS1A' and MAS1B), and a core representative of sodium-cooled fast reactors (CIRANO ZONA2A). Calculated values have been compared to measurements, and discrepancies analyzed in detail using perturbation theory. Values calculated with JEFF-3.1 were found to be within 3 standard deviations of the measured values, and at least of the same quality as the JEF-2.2 based results. (authors)« less
Pernambuco, Leandro; Espelt, Albert; Magalhães, Hipólito Virgílio; Lima, Kenio Costa de
2017-06-08
to present a guide with recommendations for translation, adaptation, elaboration and process of validation of tests in Speech and Language Pathology. the recommendations were based on international guidelines with a focus on the elaboration, translation, cross-cultural adaptation and validation process of tests. the recommendations were grouped into two Charts, one of them with procedures for translation and transcultural adaptation and the other for obtaining evidence of validity, reliability and measures of accuracy of the tests. a guide with norms for the organization and systematization of the process of elaboration, translation, cross-cultural adaptation and validation process of tests in Speech and Language Pathology was created.
RELIABILITY AND VALIDITY OF FUNCTIONAL PERFORMANCE TESTS IN DANCERS WITH HIP DYSFUNCTION
Carcia, Christopher R.; Clemente, F. Richard; Phelps, Amy L.; Martin, RobRoy L.
2013-01-01
Study Design: Quasi-experimental, repeated measures. Purpose/Background: Functional performance tests that identify hip joint impairments and assess the effect of intervention have not been adequately described for dancers. The purpose of this study was to examine the reliability and validity of hop and balance tests among a group of dancers with musculoskeletal pain in the hip region. Methods: Nineteen female dancers (age: 18.90±1.11 years; height: 164.85±6.95 cm; weight: 60.37±8.29 kg) with unilateral hip pain were assessed utilizing the cross-over reach, medial triple hop, lateral triple hop, and cross-over hop tests on two occasions, 2 days apart. Test-retest reliability and comparisons between the involved and uninvolved side for each respective test were determined. Results: Intra-class correlation coefficients for the functional performance tests ranged from 0.89-0.96. The cross-over reach test had a SEM of 2.79 cm and a MDC of 7.73 cm. The medial and lateral triple hop tests had SEM values of 7.51 cm and 8.17 cm, and MDC values of 20.81 cm and 22.62 cm, respectively. The SEM was 0.15 seconds and the MDC was 0.42 seconds for the cross-over hop test. Performance on the medial triple hop test was significantly less on the involved side (370.21±38.26 cm) compared to the uninvolved side (388.05±41.49 cm); t(18) = −4.33, p<0.01. The side-to-side comparisons of the cross-over reach test (involved mean=61.68±10.9 cm; uninvolved mean=61.69±8.63 cm); t(18) = −0.004, p=0.99, lateral triple hop test (involved mean=306.92±35.79 cm; uninvolved mean=310.68±24.49 cm); t(18) = −0.55, p=0.59, and cross-over hop test (involved mean=2.49±0.34 seconds; uninvolved mean= 2.61±0.42 seconds; t(18) = −1.84, p=0.08) were not statistically different between sides. Conclusion: The functional performance tests used in this study can be reliably performed on dancers with unilateral hip pain. The medial triple hop test was the only functional performance test with evidence of validity in side-to-side comparisons. These results suggest that the medial triple hop test may be a reliable and valid functional performance test to assess impairments related to hip pain among dancers. Level of Evidence: 3b. Non-consecutive cohort study PMID:24175123
Prince, M; Acosta, D; Ferri, C P; Guerra, M; Huang, Y; Jacob, K S; Llibre Rodriguez, J J; Salas, A; Sosa, A L; Williams, J D; Hall, K S
2011-01-01
Objective Brief screening tools for dementia for use by non-specialists in primary care have yet to be validated in non-western settings where cultural factors and limited education may complicate the task. We aimed to derive a brief version of cognitive and informant scales from the Community Screening Instrument for Dementia (CSI-D) and to carry out initial assessments of their likely validity. Methods We applied Mokken analysis to CSI-D cognitive and informant scale data from 15 022 participants in representative population-based surveys in Latin America, India and China, to identify a subset of items from each that conformed optimally to item response theory scaling principles. The validity coefficients of the resulting brief scales (area under ROC curve, optimal cutpoint, sensitivity, specificity and Youden's index) were estimated from data collected in a previous cross-cultural validation of the full CSI-D. Results Seven cognitive items (Loevinger H coefficient 0.64) and six informant items (Loevinger H coefficient 0.69) were selected with excellent hierarchical scaling properties. For the brief cognitive scale, AUROC varied between 0.88 and 0.97, for the brief informant scale between 0.92 and 1.00, and for the combined algorithm between 0.94 and 1.00. Optimal cutpoints did not vary between regions. Youden's index for the combined algorithm varied between 0.78 and 1.00 by region. Conclusion A brief version of the full CSI-D appears to share the favourable culture- and education-fair screening properties of the full assessment, despite considerable abbreviation. The feasibility and validity of the brief version still needs to be established in routine primary care. Copyright © 2010 John Wiley & Sons, Ltd. PMID:21845592
Time Domain Tool Validation Using ARES I-X Flight Data
NASA Technical Reports Server (NTRS)
Hough, Steven; Compton, James; Hannan, Mike; Brandon, Jay
2011-01-01
The ARES I-X vehicle was launched from NASA's Kennedy Space Center (KSC) on October 28, 2009 at approximately 11:30 EDT. ARES I-X was the first test flight for NASA s ARES I launch vehicle, and it was the first non-Shuttle launch vehicle designed and flown by NASA since Saturn. The ARES I-X had a 4-segment solid rocket booster (SRB) first stage and a dummy upper stage (US) to emulate the properties of the ARES I US. During ARES I-X pre-flight modeling and analysis, six (6) independent time domain simulation tools were developed and cross validated. Each tool represents an independent implementation of a common set of models and parameters in a different simulation framework and architecture. Post flight data and reconstructed models provide the means to validate a subset of the simulations against actual flight data and to assess the accuracy of pre-flight dispersion analysis. Post flight data consists of telemetered Operational Flight Instrumentation (OFI) data primarily focused on flight computer outputs and sensor measurements as well as Best Estimated Trajectory (BET) data that estimates vehicle state information from all available measurement sources. While pre-flight models were found to provide a reasonable prediction of the vehicle flight, reconstructed models were generated to better represent and simulate the ARES I-X flight. Post flight reconstructed models include: SRB propulsion model, thrust vector bias models, mass properties, base aerodynamics, and Meteorological Estimated Trajectory (wind and atmospheric data). The result of the effort is a set of independently developed, high fidelity, time-domain simulation tools that have been cross validated and validated against flight data. This paper presents the process and results of high fidelity aerospace modeling, simulation, analysis and tool validation in the time domain.
ERIC Educational Resources Information Center
Leong, Frederick T. L.; Austin, James T.; Sekaran, Uma; Komarraju, Meera
1998-01-01
Natives of India (n=172) completed Holland's Vocational Preference Inventory and job satisfaction measures. The inventory did not exhibit high external validity with this population. Congruence, consistency, and differentiation did not predict job or occupational satisfaction, suggesting cross-cultural limits on Holland's theory. (SK)
ERIC Educational Resources Information Center
Vlachopoulos, Symeon P.; Kaperoni, Maria; Moustaka, Frederiki C.; Anderson, Dean F.
2008-01-01
The present study reported on translating the Exercise Identity Scale (EIS: Anderson & Cychosz, 1994) into Greek and examining its psychometric properties and cross-cultural validity based on U.S. individuals' EIS responses. Using four samples comprising 33, 103, and 647 Greek individuals, including exercisers and nonexercisers, and a similar…
Cross-Validation of FITNESSGRAM® Health-Related Fitness Standards in Hungarian Youth
ERIC Educational Resources Information Center
Laurson, Kelly R.; Saint-Maurice, Pedro F.; Karsai, István; Csányi, Tamás
2015-01-01
Purpose: The purpose of this study was to cross-validate FITNESSGRAM® aerobic and body composition standards in a representative sample of Hungarian youth. Method: A nationally representative sample (N = 405) of Hungarian adolescents from the Hungarian National Youth Fitness Study (ages 12-18.9 years) participated in an aerobic capacity assessment…
ERIC Educational Resources Information Center
Virues-Ortega, Javier; Segui-Duran, David; Descalzo-Quero, Alberto; Carnerero, Jose Julio; Martin, Neil
2011-01-01
The Motivation Assessment Scale is an aid for hypothesis-driven functional analysis. This study presents its Spanish cross-cultural validation while examining psychometric attributes not yet explored. The study sample comprised 80 primary caregivers of children with autism. Acceptability, scaling assumptions, internal consistency, factor…
Cross-Cultural Validation of the Counselor Burnout Inventory in Hong Kong
ERIC Educational Resources Information Center
Shin, Hyojung; Yuen, Mantak; Lee, Jayoung; Lee, Sang Min
2013-01-01
This study investigated the cross-cultural validation of the Chinese translation of the Counselor Burnout Inventory (CBI) with a sample of school counselors in Hong Kong. Specifically, this study examined the CBI's factor structure using confirmatory factor analysis and calculated the effect size, to compare burnout scores among the counselors of…
Cross-Validation of a Short Form of the Marlowe-Crowne Social Desirability Scale.
ERIC Educational Resources Information Center
Zook, Avery, II; Sipps, Gary J.
1985-01-01
Presents a cross-validation of Reynolds' short form of the Marlowe-Crowne Social Desirability Scale (N=233). Researchers administered 13 items as a separate entity, calculated Cronbach's Alpha for each sex, and computed test-retest correlation for one group. Concluded that the short form is a viable alternative. (Author/NRB)
Selection of Marine Corps Drill Instructors
1980-03-01
8 4. ., ey- Construction and Cross-Validation Statistics for Drill Instructor School Performance Success Keys...Race, and School Attrition ........... ............................. ... 15 13. Key- Construction and Cross-Validation Statistics for Drill... constructed form, the Alternation Ranking of Series Drill Instruc- tors. In this form, DIs in a Series are ranked from highest to lowest in terms of their
ERIC Educational Resources Information Center
Montirosso, Rosario; Cozzi, Patrizia; Putnam, Samuel P.; Gartstein, Maria A.; Borgatti, Renato
2011-01-01
An Italian translation of the Infant Behavior Questionnaire-Revised (IBQ-R) was developed and evaluated with 110 infants, demonstrating satisfactory internal consistency, discriminant validity, and construct validity in the form of gender and age differences, as well as factorial integrity. Cross-cultural differences were subsequently evaluated…
The Halpern Critical Thinking Assessment and Real-World Outcomes: Cross-National Applications
ERIC Educational Resources Information Center
Butler, Heather A.; Dwyer, Christopher P.; Hogan, Michael J.; Franco, Amanda; Rivas, Silvia F.; Saiz, Carlos; Almeida, Leandro S.
2012-01-01
The Halpern Critical Thinking Assessment (HCTA) is a reliable measure of critical thinking that has been validated with numerous qualitatively different samples and measures of academic success (Halpern, 2010a). This paper presents several cross-national applications of the assessment, and recent work to expand the validation of the HCTA with…
Altmann, Tobias; Roth, Marcus
2018-01-01
Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS), a unidimensional and very brief scale to directly assess self-esteem stability. In four studies (total N = 826), we describe the development of the SESS and present evidence for its validity with respect to individual outcomes (life satisfaction, neuroticism, and vulnerable narcissism) and dyadic outcomes (relationship satisfaction in self- and partner ratings) through direct comparisons with existing measures. The new SESS proved to be a stronger predictor than the existing scales and had incremental validity over and above self-esteem level. The results also showed that all cross-sectional measures of self-esteem stability were only moderately associated with variability in self-esteem levels assessed longitudinally with multiple administrations of the Rosenberg Self-Esteem Scale. We discuss this validity issue, arguing that direct and indirect assessment approaches measure relevant, yet different aspects of self-esteem stability. PMID:29487551
Real-time sensor data validation
NASA Technical Reports Server (NTRS)
Bickmore, Timothy W.
1994-01-01
This report describes the status of an on-going effort to develop software capable of detecting sensor failures on rocket engines in real time. This software could be used in a rocket engine controller to prevent the erroneous shutdown of an engine due to sensor failures which would otherwise be interpreted as engine failures by the control software. The approach taken combines analytical redundancy with Bayesian belief networks to provide a solution which has well defined real-time characteristics and well-defined error rates. Analytical redundancy is a technique in which a sensor's value is predicted by using values from other sensors and known or empirically derived mathematical relations. A set of sensors and a set of relations among them form a network of cross-checks which can be used to periodically validate all of the sensors in the network. Bayesian belief networks provide a method of determining if each of the sensors in the network is valid, given the results of the cross-checks. This approach has been successfully demonstrated on the Technology Test Bed Engine at the NASA Marshall Space Flight Center. Current efforts are focused on extending the system to provide a validation capability for 100 sensors on the Space Shuttle Main Engine.
Cross-cultural adaptation of an Arabic version of the 10-item hearing handicap inventory.
Weinstein, Barbara E; Rasheedy, Doha; Taha, Hend M; Fatouh, Fathy N
2015-05-01
The purpose of this study was to translate and culturally adapt an Arabic version of the hearing handicap inventory for the elderly - screening (HHIE-S). The HHIE-S was translated following cross-cultural adaptation guidelines, and pretested in 20 elderly patients with hearing impairment. Next, the adapted Arabic HHIE-S underwent psychometric evaluation. The results were confirmed by pure-tone audiometer (PTA) examination. The patients completed the HHIE-S again after one hour. The validation of the questionnaire using Cronbach's alpha (internal consistency), (construct validity), and intraclass correlation coefficients (repeatability) was performed. Twenty elderly subjects with hearing impairment were recruited for the pretesting stage, and 100 elderly subjects were recruited for the psychometric evaluation stage. Patients with acute illness, functional dependency, cognitive impairment, and previous users of hearing aids were excluded. The adapted Arabic HHIE-S showed good internal consistency (α = 0.902). Construct validity was good, as high correlations were found between the scale and the PTA outcome (r = 0.688, p = 0.000). Repeatability was high (ICC = 0.986). This study showed that the adapted Arabic HHIE-S is a valid and reliable questionnaire for the assessment of handicapping hearing impairment in Egyptian elderly patients.
Casemix classification payment for sub-acute and non-acute inpatient care, Thailand.
Khiaocharoen, Orathai; Pannarunothai, Supasit; Zungsontiporn, Chairoj; Riewpaiboon, Wachara
2010-07-01
There is a need to develop other casemix classifications, apart from DRG for sub-acute and non-acute inpatient care payment mechanism in Thailand. To develop a casemix classification for sub-acute and non-acute inpatient service. The study began with developing a classification system, analyzing cost, assigning payment weights, and ended with testing the validity of this new casemix system. Coefficient of variation, reduction in variance, linear regression, and split-half cross-validation were employed. The casemix for sub-acute and non-acute inpatient services contained 98 groups. Two percent of them had a coefficient of variation of the cost of higher than 1.5. The reduction in variance of cost after the classification was 32%. Two classification variables (physical function and the rehabilitation impairment categories) were key determinants of the cost (adjusted R2 = 0.749, p = .001). Validity results of split-half cross-validation of sub-acute and non-acute inpatient service were high. The present study indicated that the casemix for sub-acute and non-acute inpatient services closely predicted the hospital resource use and should be further developed for payment of the inpatients sub-acute and non-acute phase.
Altmann, Tobias; Roth, Marcus
2018-01-01
Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS), a unidimensional and very brief scale to directly assess self-esteem stability. In four studies (total N = 826), we describe the development of the SESS and present evidence for its validity with respect to individual outcomes (life satisfaction, neuroticism, and vulnerable narcissism) and dyadic outcomes (relationship satisfaction in self- and partner ratings) through direct comparisons with existing measures. The new SESS proved to be a stronger predictor than the existing scales and had incremental validity over and above self-esteem level. The results also showed that all cross-sectional measures of self-esteem stability were only moderately associated with variability in self-esteem levels assessed longitudinally with multiple administrations of the Rosenberg Self-Esteem Scale. We discuss this validity issue, arguing that direct and indirect assessment approaches measure relevant, yet different aspects of self-esteem stability.
Scaling Cross Sections for Ion-atom Impact Ionization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Igor D. Kaganovich; Edward Startsev; Ronald C. Davidson
2003-06-06
The values of ion-atom ionization cross sections are frequently needed for many applications that utilize the propagation of fast ions through matter. When experimental data and theoretical calculations are not available, approximate formulas are frequently used. This paper briefly summarizes the most important theoretical results and approaches to cross section calculations in order to place the discussion in historical perspective and offer a concise introduction to the topic. Based on experimental data and theoretical predictions, a new fit for ionization cross sections is proposed. The range of validity and accuracy of several frequently used approximations (classical trajectory, the Born approximation,more » and so forth) are discussed using, as examples, the ionization cross sections of hydrogen and helium atoms by various fully stripped ions.« less
Measurement properties of depression questionnaires in patients with diabetes: a systematic review.
van Dijk, Susan E M; Adriaanse, Marcel C; van der Zwaan, Lennart; Bosmans, Judith E; van Marwijk, Harm W J; van Tulder, Maurits W; Terwee, Caroline B
2018-06-01
To conduct a systematic review on measurement properties of questionnaires measuring depressive symptoms in adult patients with type 1 or type 2 diabetes. A systematic review of the literature in MEDLINE, EMbase and PsycINFO was performed. Full text, original articles, published in any language up to October 2016 were included. Eligibility for inclusion was independently assessed by three reviewers who worked in pairs. Methodological quality of the studies was evaluated by two independent reviewers using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist. Quality of the questionnaires was rated per measurement property, based on the number and quality of the included studies and the reported results. Of 6286 unique hits, 21 studies met our criteria evaluating nine different questionnaires in multiple settings and languages. The methodological quality of the included studies was variable for the different measurement properties: 9/15 studies scored 'good' or 'excellent' on internal consistency, 2/5 on reliability, 0/1 on content validity, 10/10 on structural validity, 8/11 on hypothesis testing, 1/5 on cross-cultural validity, and 4/9 on criterion validity. For the CES-D, there was strong evidence for good internal consistency, structural validity, and construct validity; moderate evidence for good criterion validity; and limited evidence for good cross-cultural validity. The PHQ-9 and WHO-5 also performed well on several measurement properties. However, the evidence for structural validity of the PHQ-9 was inconclusive. The WHO-5 was less extensively researched and originally not developed to measure depression. Currently, the CES-D is best supported for measuring depressive symptoms in diabetes patients.
Hansen, Clint; Venture, Gentiane; Rezzoug, Nasser; Gorce, Philippe; Isableu, Brice
2014-05-07
Over the last decades a variety of research has been conducted with the goal to improve the Body Segment Inertial Parameters (BSIP) estimations but to our knowledge a real validation has never been completely successful, because no ground truth is available. The aim of this paper is to propose a validation method for a BSIP identification method (IM) and to confirm the results by comparing them with recalculated contact forces using inverse dynamics to those obtained by a force plate. Furthermore, the results are compared with the recently proposed estimation method by Dumas et al. (2007). Additionally, the results are cross validated with a high velocity overarm throwing movement. Throughout conditions higher correlations, smaller metrics and smaller RMSE can be found for the proposed BSIP estimation (IM) which shows its advantage compared to recently proposed methods as of Dumas et al. (2007). The purpose of the paper is to validate an already proposed method and to show that this method can be of significant advantage compared to conventional methods. Copyright © 2014 Elsevier Ltd. All rights reserved.
Lauffer, A; Solé, L; Bernstein, S; Lopes, M H; Francisconi, C F
2013-01-01
The development and validation of questionnaires for evaluating quality of life (QoL) has become an important area of research. However, there is a proliferation of non-validated measuring instruments in the health setting that do not contribute to advances in scientific knowledge. To present, through the analysis of available validated questionnaires, a checklist of the practical aspects of how to carry out the cross-cultural adaptation of QoL questionnaires (generic, or disease-specific) so that no step is overlooked in the evaluation process, and thus help prevent the elaboration of insufficient or incomplete validations. We have consulted basic textbooks and Pubmed databases using the following keywords quality of life, questionnaires, and gastroenterology, confined to «validation studies» in English, Spanish, and Portuguese, and with no time limit, for the purpose of analyzing the translation and validation of the questionnaires available through the Mapi Institute and PROQOLID websites. A checklist is presented to aid in the planning and carrying out of the cross-cultural adaptation of QoL questionnaires, in conjunction with a glossary of key terms in the area of knowledge. The acronym DSTAC was used, which refers to each of the 5 stages involved in the recommended procedure. In addition, we provide a table of the QoL instruments that have been validated into Spanish. This article provides information on how to adapt QoL questionnaires from a cross-cultural perspective, as well as to minimize common errors. Copyright © 2012 Asociación Mexicana de Gastroenterología. Published by Masson Doyma México S.A. All rights reserved.
Psychometric evaluation of the Revised Professional Practice Environment (RPPE) scale.
Erickson, Jeanette Ives; Duffy, Mary E; Ditomassi, Marianne; Jones, Dorothy
2009-05-01
The purpose was to examine the psychometric properties of the Revised Professional Practice Environment (RPPE) scale. Despite renewed focus on studying health professionals' practice environments, there are still few reliable and valid instruments available to assist nurse administrators in decision making. A psychometric evaluation using a random-sample cross-validation procedure (calibration sample [CS], n = 775; validation sample [VS], n = 775) was undertaken. Cronbach alpha internal consistency reliability of the total score (r = 0.93 [CS] and 0.92 [VS]), resulting subscale scores (r range: 0.80-0.87 [CS], 0.81-0.88 [VS]), and principal components analyses with Varimax rotation and Kaiser normalization (8 components, 59.2% variance [CS], 59.7% [VS]) produced almost identical results in both samples. The multidimensional RPPE is a psychometrically sound measure of 8 components of the professional practice environment in the acute care setting and sufficiently reliable and valid for use as independent subscales in healthcare research.
Lupi, Jaqueline Basilio; Carvalho de Abreu, Daniela Cristina; Ferreira, Mariana Candido; Oliveira, Renê Donizeti Ribeiro de; Chaves, Thais Cristina
2017-08-01
This study aimed to culturally adapt and validate the Revised Fibromyalgia Impact Questionnaire (FIQR) to Brazilian Portuguese, by the use of analysis of internal consistency, reliability, and construct and structural validity. A total of 100 female patients with fibromyalgia participated in the validation process of the Brazilian Portuguese version of the FIQR (FIQR-Br).The intraclass correlation coefficient (ICC) was used for statistical analysis of reliability (test-retest), Cronbach's alpha for internal consistency, Pearson's rank correlation for construct validity, and confirmatory factor analysis (CFA) for structural validity. It was verified excellent levels of reliability, with ICC greater than 0.75 for all questions and domains of the FIQR-Br. For internal consistency, alpha values greater than 0.70 for the items and domains of the questionnaire were observed. Moderate (0.40 < r < 0.70) and strong (r > 0.70) correlations were observed for the scores of domains and total score between the FIQR-Br and FIQ-Br. The structure of the three domains of the FIQR-Br was confirmed by CFA. The results of this study suggest that that the FIQR-Br is a reliable and valid instrument for assessing fibromyalgia-related impact, and supports its use in clinical settings and research. The structure of the three domains of the FIQR-Br was also confirmed. Implications for Rehabilitation Fibromyalgia is a chronic musculoskeletal disorder characterized by widespread and diffuse pain, fatigue, sleep disturbances, and depression. The disease significantly impairs patients' quality of life and can be highly disabling. To be used in multicenter research efforts, the Revised Fibromyalgia Impact Questionnaire (FIQR) must be cross-culturally validated and psychometrically tested. This paper will make available a new version of the FIQR-Br since another version already exists, but there are concerns about its measurement properties. The availability of an instrument adapted to and validated for Brazilian Portuguese may make it possible to reliably verify the effects of rehabilitation programs on disability from fibromyalgia. The FIQR-Br showed results comparable with other versions of the FIQR in other languages, thereby enabling comparison of effects of rehabilitation interventions on disability from fibromyalgia conducted in Brazil with results of studies carried out in other parts of the world.
Cross-cultural adaptation and validation of the neonatal/infant Braden Q risk assessment scale.
de Lima, Edson Luiz; de Brito, Maria José Azevedo; de Souza, Diba Maria Sebba Tosta; Salomé, Geraldo Magela; Ferreira, Lydia Masako
2016-02-01
To translate into Brazilian Portuguese and cross-culturally adapt the Neonatal/Infant Braden Q Risk Assessment Scale (Neonatal/Infant Braden Q Scale), and test the psychometric properties, reproducibility and validity of the instrument. There is a lack of studies on the development of pressure ulcers in children, especially in neonates. Thirty professionals participated in the cross-cultural adaptation of the Brazilian-Portuguese version of the scale. Fifty neonates of both sexes were assessed between July 2013 and June 2014. Reliability and reproducibility were tested in 20 neonates and construct validity was measured by correlating the Neonatal/Infant Braden Q Scale with the Braden Q Risk Assessment Scale (Braden Q Scale). Discriminant validity was assessed by comparing the scores of neonates with and without ulcers. The scale showed inter-rater reliability (ICC = 0.98; P < 0.001) and intra-rater reliability (ICC = 0.79; P < 0.001). A strong correlation was found between the Neonatal/Infant Braden Q Scale and Braden Q Scale (r = 0.96; P < 0.001). The cross-culturally adapted Brazilian version of the Neonatal/Infant Braden Q Scale is a reliable instrument, showing face, content and construct validity. Copyright © 2015 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.
Zhou, Hongzhen; Zhu, Yafang; Zhang, Xiaomei
2017-01-01
This study aimed to validate the Chinese version of the Functional Oral Intake Scale (FOIS) score in acute stroke patients with dysphagia. A sample of 128 consecutive patients with acute stroke, admitted to Department of Neurology from April to October in 2016, completed the FOIS. The interrater reliability, criterion validity, discriminant validity, cross validation, and the sensitivity of FOIS scale were evaluated. Results showed that rater agreements were excellent for FOIS (Kw = 0.881, p < 0.001). A highly negative correlation between FOIS and WST (water swallow test) was detected (r = -0.937, p < 0.001). There was significant difference for FOIS level of patients with different evaluation outcomes (χ2 = 126.551, p < 0.001). The FOIS evaluation results were significantly correlated with two physiological measures of swallowing. The Chinese version of the FOIS score is a reliable scale for evaluating the level of oral feeding function in patients with acute stroke.
Higgs boson gluon-fusion production beyond threshold in N 3LO QCD
Anastasiou, Charalampos; Duhr, Claude; Dulat, Falko; ...
2015-03-18
In this study, we compute the gluon fusion Higgs boson cross-section at N 3LO through the second term in the threshold expansion. This calculation constitutes a major milestone towards the full N 3LO cross section. Our result has the best formal accuracy in the threshold expansion currently available, and includes contributions from collinear regions besides subleading corrections from soft and hard regions, as well as certain logarithmically enhanced contributions for general kinematics. We use our results to perform a critical appraisal of the validity of the threshold approximation at N 3LO in perturbative QCD.
Santo, Ruth Miyuki; Ribeiro-Ferreira, Felipe; Alves, Milton Ruiz; Epstein, Jonathan; Novaes, Priscila
2015-04-01
To provide a reliable, validated, and culturally adapted instrument that may be used in monitoring dry eye in Brazilian patients and to discuss the strategies for the enhancement of the cross-cultural adaptation and validation process of a self-report measure for dry eye. The cross-cultural adaptation process (CCAP) of the original Ocular Surface Disease Index (OSDI) into Brazilian-Portuguese was conducted using a 9-step guideline. The synthesis of translations was tested twice, for face and content validity, by different subjects (focus groups and cognitive interviews). The expert committee contributed on several steps, and back translations were based on the final rather than the prefinal version. For validation, the adapted version was applied in a prospective longitudinal study to 101 patients from the Dry Eye Clinic at the General Hospital of the University of São Paulo, Brazil. Simultaneously to the OSDI, patients answered the short form-36 health survey (SF-36) and the 25-item visual function questionnaire (VFQ-25) and underwent clinical evaluation. Internal consistency, test-retest reliability, and measure validity were assessed. Cronbach's alpha value of the cross-culturally adapted Brazilian-Portuguese version of the OSDI was 0.905, and the intraclass correlation coefficient was 0.801. There was a statistically significant difference between OSDI scores in patients with dry eye (41.15 ± 27.40) and without dry eye (17.88 ± 17.09). There was a negative association between OSDI and VFQ-25 total score (P < 0.01) and between the OSDI and five SF-36 domains. OSDI scores correlated positively with lissamine green and fluorescein staining scores (P < 0.001) and negatively with Schirmer test I and tear break-up time values (P < 0.001). Although most of the reviewed guidelines on CCAP involve well-defined steps (translation, synthesis/reconciliation, back translation, expert committee review, pretesting), the proposed methodological steps have not been applied in a uniform way. The translation and adaptation process requires skill, knowledge, experience, and a considerable investment of time to maximize the attainment of semantic, idiomatic, experiential, and conceptual equivalence between the source and target questionnaires. A well-established guideline resulted in a culturally adapted Brazilian-Portuguese version of the OSDI, tested and validated on a sample of Brazilian population, and proved to be a valid and reliable instrument for assessing patients with dry eye syndrome in Brazil. Copyright © 2015 Elsevier Inc. All rights reserved.
Ridenour, Ty A.; Willis, David; Bogen, Debra L.; Novak, Scott; Scherer, Jennifer; Reynolds, Maureen D.; Zhai, Zu Wei; Tarter, Ralph E.
2015-01-01
Background Youth substance use (SU) is prevalent and costly, affecting mental and physical health. American Academy of Pediatrics and Affordable Care Act call for SU screening and prevention. The Youth Risk Index© (YRI) was tested as a screening tool for having initiated and propensity to initiate SU before high school (which forecasts SU disorder). YRI was hypothesized to have good to excellent psychometrics, feasibility and stakeholder acceptability for use during well-child check-ups. Design A high-risk longitudinal design with two cross-sectional replication samples, ages 9–13 was used. Analyses included receiver operating characteristics and regression analyses. Participants A one-year longitudinal sample (N=640) was used for YRI derivation. Replication samples were a cross-sectional sample (N=345) and well-child check-up patients (N=105) for testing feasibility, validity and acceptability as a screening tool. Results YRI has excellent test-retest reliability and good sensitivity and specificity for concurrent and one-year-later SU (odds ratio=7.44 CI=4.3–13.0) and conduct problems (odds ratios=7.33 CI=3.9–13.7). Results were replicated in both cross-sectional samples. Well-child patients, parents and pediatric staff rated YRI screening as important, acceptable, and a needed service. Conclusions Identifying at-risk youth prior to age 13 could reap years of opportunity to intervene before onset of SU disorder. Most results pertained to YRI’s association with concurrent or recent past risky behaviors; further replication ought to specify its predictive validity, especially adolescent-onset risky behaviors. YRI well identifies youth at risk for SU and conduct problems prior to high school, is feasible and valid for screening during well-child check-ups, and is acceptable to stakeholders. PMID:25765481
Smerecnik, Chris M R; Mesters, Ilse; Candel, Math J J M; De Vries, Hein; De Vries, Nanne K
2012-01-01
The role of information processing in understanding people's responses to risk information has recently received substantial attention. One limitation of this research concerns the unavailability of a validated questionnaire of information processing. This article presents two studies in which we describe the development and validation of the Information-Processing Questionnaire to meet that need. Study 1 describes the development and initial validation of the questionnaire. Participants were randomized to either a systematic processing or a heuristic processing condition after which they completed a manipulation check and the initial 15-item questionnaire and again two weeks later. The questionnaire was subjected to factor reliability and validity analyses on both measurement times for purposes of cross-validation of the results. A two-factor solution was observed representing a systematic processing and a heuristic processing subscale. The resulting scale showed good reliability and validity, with the systematic condition scoring significantly higher on the systematic subscale and the heuristic processing condition significantly higher on the heuristic subscale. Study 2 sought to further validate the questionnaire in a field study. Results of the second study corresponded with those of Study 1 and provided further evidence of the validity of the Information-Processing Questionnaire. The availability of this information-processing scale will be a valuable asset for future research and may provide researchers with new research opportunities. © 2011 Society for Risk Analysis.
Bittante, G; Ferragina, A; Cipolat-Gotet, C; Cecchinato, A
2014-10-01
Cheese yield is an important technological trait in the dairy industry. The aim of this study was to infer the genetic parameters of some cheese yield-related traits predicted using Fourier-transform infrared (FTIR) spectral analysis and compare the results with those obtained using an individual model cheese-producing procedure. A total of 1,264 model cheeses were produced using 1,500-mL milk samples collected from individual Brown Swiss cows, and individual measurements were taken for 10 traits: 3 cheese yield traits (fresh curd, curd total solids, and curd water as a percent of the weight of the processed milk), 4 milk nutrient recovery traits (fat, protein, total solids, and energy of the curd as a percent of the same nutrient in the processed milk), and 3 daily cheese production traits per cow (fresh curd, total solids, and water weight of the curd). Each unprocessed milk sample was analyzed using a MilkoScan FT6000 (Foss, Hillerød, Denmark) over the spectral range, from 5,000 to 900 wavenumber × cm(-1). The FTIR spectrum-based prediction models for the previously mentioned traits were developed using modified partial least-square regression. Cross-validation of the whole data set yielded coefficients of determination between the predicted and measured values in cross-validation of 0.65 to 0.95 for all traits, except for the recovery of fat (0.41). A 3-fold external validation was also used, in which the available data were partitioned into 2 subsets: a training set (one-third of the herds) and a testing set (two-thirds). The training set was used to develop calibration equations, whereas the testing subsets were used for external validation of the calibration equations and to estimate the heritabilities and genetic correlations of the measured and FTIR-predicted phenotypes. The coefficients of determination between the predicted and measured values in cross-validation results obtained from the training sets were very similar to those obtained from the whole data set, but the coefficient of determination of validation values for the external validation sets were much lower for all traits (0.30 to 0.73), and particularly for fat recovery (0.05 to 0.18), for the training sets compared with the full data set. For each testing subset, the (co)variance components for the measured and FTIR-predicted phenotypes were estimated using bivariate Bayesian analyses and linear models. The intraherd heritabilities for the predicted traits obtained from our internal cross-validation using the whole data set ranged from 0.085 for daily yield of curd solids to 0.576 for protein recovery, and were similar to those obtained from the measured traits (0.079 to 0.586, respectively). The heritabilities estimated from the testing data set used for external validation were more variable but similar (on average) to the corresponding values obtained from the whole data set. Moreover, the genetic correlations between the predicted and measured traits were high in general (0.791 to 0.996), and they were always higher than the corresponding phenotypic correlations (0.383 to 0.995), especially for the external validation subset. In conclusion, we herein report that application of the cross-validation technique to the whole data set tended to overestimate the predictive ability of FTIR spectra, give more precise phenotypic predictions than the calibrations obtained using smaller data sets, and yield genetic correlations similar to those obtained from the measured traits. Collectively, our findings indicate that FTIR predictions have the potential to be used as indicator traits for the rapid and inexpensive selection of dairy populations for improvement of cheese yield, milk nutrient recovery in curd, and daily cheese production per cow. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Validation of Cross Sections with Criticality Experiment and Reaction Rates: the Neptunium Case
NASA Astrophysics Data System (ADS)
Leong, L. S.; Tassan-Got, L.; Audouin, L.; Berthier, B.; Le Naour, C.; Stéphan, C.; Paradela, C.; Tarrío, D.; Duran, I.
2014-04-01
The 237Np neutron-induced fission cross section has been recently measured in a large energy range (from eV to GeV) at the n_TOF facility at CERN. When compared to previous measurements the n_TOF fission cross section appears to be higher by 5-7% beyond the fission threshold. To check the relevance of the n_TOF data, we considered a criticality experiment performed at Los Alamos with a 6 kg sphere of 237Np, surrounded by uranium highly enriched in 235U so as to approach criticality with fast neutrons. The multiplication factor keff of the calculation is in better agreement with the experiment when we replace the ENDF/B-VII.0 evaluation of the 237Np fission cross section by the n_TOF data. We also explored the hypothesis of deficiencies of the inelastic cross section in 235U which has been invoked by some authors to explain the deviation of 750 pcm. The large modification needed to reduce the deviation seems to be incompatible with existing inelastic cross section measurements. Also we show that the νbar of 237Np can hardly be incriminated because of the high accuracy of the existing data. Fission rate ratios or averaged fission cross sections measured in several fast neutron fields seem to give contradictory results on the validation of the 237Np cross section but at least one of the benchmark experiments, where the active deposits have been well calibrated for the number of atoms, favors the n_TOF data set. These outcomes support the hypothesis of a higher fission cross section of 237Np.
Baek, Sora; Park, Hee-Won; Lee, Yookyung; Grace, Sherry L; Kim, Won-Seok
2017-10-01
To perform a translation and cross-cultural adaptation of the Cardiac Rehabilitation Barriers Scale (CRBS) for use in Korea, followed by psychometric validation. The CRBS was developed to assess patients' perception of the degree to which patient, provider and health system-level barriers affect their cardiac rehabilitation (CR) participation. The CRBS consists of 21 items (barriers to adherence) rated on a 5-point Likert scale. The first phase was to translate and cross-culturally adapt the CRBS to the Korean language. After back-translation, both versions were reviewed by a committee. The face validity was assessed in a sample of Korean patients (n=53) with history of acute myocardial infarction that did not participate in CR through semi-structured interviews. The second phase was to assess the construct and criterion validity of the Korean translation as well as internal reliability, through administration of the translated version in 104 patients, principle component analysis with varimax rotation and cross-referencing against CR use, respectively. The length, readability, and clarity of the questionnaire were rated well, demonstrating face validity. Analysis revealed a six-factor solution, demonstrating construct validity. Cronbach's alpha was greater than 0.65. Barriers rated highest included not knowing about CR and not being contacted by a program. The mean CRBS score was significantly higher among non-attendees (2.71±0.26) than CR attendees (2.51±0.18) (p<0.01). The Korean version of CRBS has demonstrated face, content and criterion validity, suggesting it may be useful for assessing barriers to CR utilization in Korea.
Fast Estimation of Strains for Cross-Beams Six-Axis Force/Torque Sensors by Mechanical Modeling
Ma, Junqing; Song, Aiguo
2013-01-01
Strain distributions are crucial criteria of cross-beams six-axis force/torque sensors. The conventional method for calculating the criteria is to utilize Finite Element Analysis (FEA) to get numerical solutions. This paper aims to obtain analytical solutions of strains under the effect of external force/torque in each dimension. Genetic mechanical models for cross-beams six-axis force/torque sensors are proposed, in which deformable cross elastic beams and compliant beams are modeled as quasi-static Timoshenko beam. A detailed description of model assumptions, model idealizations, application scope and model establishment is presented. The results are validated by both numerical FEA simulations and calibration experiments, and test results are found to be compatible with each other for a wide range of geometric properties. The proposed analytical solutions are demonstrated to be an accurate estimation algorithm with higher efficiency. PMID:23686144
Psychometric Properties and Validation of the Arabic Social Media Addiction Scale.
Al-Menayes, Jamal
2015-01-01
This study investigated the psychometric properties of the Arabic version of the SMAS. SMAS is a variant of IAT customized to measure addiction to social media instead of the Internet as a whole. Using a self-report instrument on a cross-sectional sample of undergraduate students, the results revealed the following. First, the exploratory factor analysis showed that a three-factor model fits the data well. Second, concurrent validity analysis showed the SMAS to be a valid measure of social media addiction. However, further studies and data should verify the hypothesized model. Finally, this study showed that the Arabic version of the SMAS is a valid and reliable instrument for use in measuring social media addiction in the Arab world.
Psychometric Properties and Validation of the Arabic Social Media Addiction Scale
Al-Menayes, Jamal
2015-01-01
This study investigated the psychometric properties of the Arabic version of the SMAS. SMAS is a variant of IAT customized to measure addiction to social media instead of the Internet as a whole. Using a self-report instrument on a cross-sectional sample of undergraduate students, the results revealed the following. First, the exploratory factor analysis showed that a three-factor model fits the data well. Second, concurrent validity analysis showed the SMAS to be a valid measure of social media addiction. However, further studies and data should verify the hypothesized model. Finally, this study showed that the Arabic version of the SMAS is a valid and reliable instrument for use in measuring social media addiction in the Arab world. PMID:26347848
Uludag, K; Kohl, M; Steinbrink, J; Obrig, H; Villringer, A
2002-01-01
Using the modified Lambert-Beer law to analyze attenuation changes measured noninvasively during functional activation of the brain might result in an insufficient separation of chromophore changes ("cross talk") due to the wavelength dependence of the partial path length of photons in the activated volume of the head. The partial path length was estimated by performing Monte Carlo simulations on layered head models. When assuming cortical activation (e.g., in the depth of 8-12 mm), we determine negligible cross talk when considering changes in oxygenated and deoxygenated hemoglobin. But additionally taking changes in the redox state of cytochrome-c-oxidase into account, this analysis results in significant artifacts. An analysis developed for changes in mean time of flight--instead of changes in attenuation--reduces the cross talk for the layers of cortical activation. These results were validated for different oxygen saturations, wavelength combinations and scattering coefficients. For the analysis of changes in oxygenated and deoxygenated hemoglobin only, low cross talk was also found when the activated volume was assumed to be a 4-mm-diam sphere.
CrossTalk: The Journal of Defense Software Engineering. Volume 26, Number 6, November/December 2013
2013-12-01
requirements during sprint planning. Automated scanning, which includes automated code-review tools, allows the expert to monitor the system... sprint . This enables the validator to leverage the test results for formal validation and verification, and perform a shortened “hybrid” style of IV&V...per SPRINT (1-4 weeks) 1 week 1 Month Up to four months Ø Deliverable product to user Ø Security posture assessed Ø Accredited to field/operate
Internal Consistency, Retest Reliability, and their Implications For Personality Scale Validity
McCrae, Robert R.; Kurtz, John E.; Yamagata, Shinji; Terracciano, Antonio
2010-01-01
We examined data (N = 34,108) on the differential reliability and validity of facet scales from the NEO Inventories. We evaluated the extent to which (a) psychometric properties of facet scales are generalizable across ages, cultures, and methods of measurement; and (b) validity criteria are associated with different forms of reliability. Composite estimates of facet scale stability, heritability, and cross-observer validity were broadly generalizable. Two estimates of retest reliability were independent predictors of the three validity criteria; none of three estimates of internal consistency was. Available evidence suggests the same pattern of results for other personality inventories. Internal consistency of scales can be useful as a check on data quality, but appears to be of limited utility for evaluating the potential validity of developed scales, and it should not be used as a substitute for retest reliability. Further research on the nature and determinants of retest reliability is needed. PMID:20435807
Prospects for Genomic Selection in Cassava Breeding.
Wolfe, Marnin D; Del Carpio, Dunia Pino; Alabi, Olumide; Ezenwaka, Lydia C; Ikeogu, Ugochukwu N; Kayondo, Ismail S; Lozano, Roberto; Okeke, Uche G; Ozimati, Alfred A; Williams, Esuma; Egesi, Chiedozie; Kawuki, Robert S; Kulakow, Peter; Rabbi, Ismail Y; Jannink, Jean-Luc
2017-11-01
Cassava ( Crantz) is a clonally propagated staple food crop in the tropics. Genomic selection (GS) has been implemented at three breeding institutions in Africa to reduce cycle times. Initial studies provided promising estimates of predictive abilities. Here, we expand on previous analyses by assessing the accuracy of seven prediction models for seven traits in three prediction scenarios: cross-validation within populations, cross-population prediction and cross-generation prediction. We also evaluated the impact of increasing the training population (TP) size by phenotyping progenies selected either at random or with a genetic algorithm. Cross-validation results were mostly consistent across programs, with nonadditive models predicting of 10% better on average. Cross-population accuracy was generally low (mean = 0.18) but prediction of cassava mosaic disease increased up to 57% in one Nigerian population when data from another related population were combined. Accuracy across generations was poorer than within-generation accuracy, as expected, but accuracy for dry matter content and mosaic disease severity should be sufficient for rapid-cycling GS. Selection of a prediction model made some difference across generations, but increasing TP size was more important. With a genetic algorithm, selection of one-third of progeny could achieve an accuracy equivalent to phenotyping all progeny. We are in the early stages of GS for this crop but the results are promising for some traits. General guidelines that are emerging are that TPs need to continue to grow but phenotyping can be done on a cleverly selected subset of individuals, reducing the overall phenotyping burden. Copyright © 2017 Crop Science Society of America.
Zhou, Hongmei; Romero, Stephanie Ballon; Qin, Xiao
2016-10-01
This paper aimed to examine pedestrians' self-reported violating crossing behavior intentions by applying the theory of planned behavior (TPB). We studied the behavior intentions regarding instrumental attitude, subjective norm, perceived behavioral control, the three basic components of TPB, and extended the theory by adding new factors including descriptive norm, perceived risk and conformity tendency to evaluate their respective impacts on pedestrians' behavior intentions. A questionnaire presented with a scenario that pedestrians crossed the road violating the pedestrian lights at an intersection was designed, and the survey was conducted in Dalian, China. Based on the 260 complete and valid responses, reliability and validity of the data for each question was evaluated. The data were then analyzed by using the structural equation modeling (SEM). The results showed that people had a negative attitude toward the behavior of violating road-crossing rules; they perceived social influences from their family and friends; and they believed that this kind of risky behavior would potentially harm them in a traffic accident. The results also showed that instrumental attitude and subjective norm were significant in the basic TPB model. After adding descriptive norm, subjective norm was no more significant. Other models showed that conformity tendency was a strong predictor, indicating that the presence of other pedestrians would influence behavioral intention. The findings could help to design more effective interventions and safety campaigns, such as changing people's attitude toward this violation behavior, correcting the social norms, increasing their safety awareness, etc. in order to reduce pedestrians' road crossing violations. Copyright © 2015 Elsevier Ltd. All rights reserved.
Validity of VO(2 max) in predicting blood volume: implications for the effect of fitness on aging
NASA Technical Reports Server (NTRS)
Convertino, V. A.; Ludwig, D. A.
2000-01-01
A multiple regression model was constructed to investigate the premise that blood volume (BV) could be predicted using several anthropometric variables, age, and maximal oxygen uptake (VO(2 max)). To test this hypothesis, age, calculated body surface area (height/weight composite), percent body fat (hydrostatic weight), and VO(2 max) were regressed on to BV using data obtained from 66 normal healthy men. Results from the evaluation of the full model indicated that the most parsimonious result was obtained when age and VO(2 max) were regressed on BV expressed per kilogram body weight. The full model accounted for 52% of the total variance in BV per kilogram body weight. Both age and VO(2 max) were related to BV in the positive direction. Percent body fat contributed <1% to the explained variance in BV when expressed in absolute BV (ml) or as BV per kilogram body weight. When the model was cross validated on 41 new subjects and BV per kilogram body weight was reexpressed as raw BV, the results indicated that the statistical model would be stable under cross validation (e.g., predictive applications) with an accuracy of +/- 1,200 ml at 95% confidence. Our results support the hypothesis that BV is an increasing function of aerobic fitness and to a lesser extent the age of the subject. The results may have implication as to a mechanism by which aerobic fitness and activity may be protective against reduced BV associated with aging.
Stanifer, John W.; Karia, Francis; Voils, Corrine I.; Turner, Elizabeth L.; Maro, Venance; Shimbi, Dionis; Kilawe, Humphrey; Lazaro, Matayo; Patel, Uptal D.
2015-01-01
Introduction Non-communicable diseases are a growing global burden, and structured surveys can identify critical gaps to address this epidemic. In sub-Saharan Africa, there are very few well-tested survey instruments measuring population attributes related to non-communicable diseases. To meet this need, we have developed and validated the first instrument evaluating knowledge, attitudes and practices pertaining to chronic kidney disease in a Swahili-speaking population. Methods and Results Between December 2013 and June 2014, we conducted a four-stage, mixed-methods study among adults from the general population of northern Tanzania. In stage 1, the survey instrument was constructed in English by a group of cross-cultural experts from multiple disciplines and through content analysis of focus group discussions to ensure local significance. Following translation, in stage 2, we piloted the survey through cognitive and structured interviews, and in stage 3, in order to obtain initial evidence of reliability and construct validity, we recruited and then administered the instrument to a random sample of 606 adults. In stage 4, we conducted analyses to establish test-retest reliability and known-groups validity which was informed by thematic analysis of the qualitative data in stages 1 and 2. The final version consisted of 25 items divided into three conceptual domains: knowledge, attitudes and practices. Each item demonstrated excellent test-retest reliability with established content and construct validity. Conclusions We have developed a reliable and valid cross-cultural survey instrument designed to measure knowledge, attitudes and practices of chronic kidney disease in a Swahili-speaking population of Northern Tanzania. This instrument may be valuable for addressing gaps in non-communicable diseases care by understanding preferences regarding healthcare, formulating educational initiatives, and directing development of chronic disease management programs that incorporate chronic kidney disease across sub-Saharan Africa. PMID:25811781
Torabi, Hadi; Khoddami, Seyyedeh Maryam; Ansari, Noureddin Nakhostin; Dabirmoghaddam, Payman
2016-11-01
To cross-culturally adapt of Persian Vocal Tract Discomfort (VTDp) scale and evaluate its validity and reliability in the assessment of patients with muscle tension dysphonia (MTD). A cross-sectional and prospective cohort design was used to psychometrically test the VTDp. The VTD scale was cross-culturally adapted into Persian language following standard forward-backward translations. The VTDp scale was administrated to 100 patients with MTD (54 men and 46 women; mean age: 38.05 ± 10.02 years) and 50 healthy volunteers (26 men and 24 women; mean age: 36.50 ± 12.27 years). Forty-five patients with MTD completed the VTDp 7 days later for test-retest reliability. Patients also completed the Persian Voice Handicap Index (VHIp) to assess construct validity. The results of discriminative validity demonstrated that the VTDp was able to discriminate between patients with MTD and healthy participants. The internal consistency was confirmed with Cronbach α .77 and 0.73 for VTDp frequency and severity subscales, respectively. The test-retest reliability was excellent with an intraclass correlation coefficient (ICC agreement ) of 0.93 for the frequency subscale and 0.91 for the severity subscale. Construct validity of the VTDp was shown with significant correlations between the VTDp frequency and severity subscales and the VHIp total scores (0.36 and 0.37, respectively). The standard error of measurement and smallest detectable change values for VTDp frequency (2.11 and 5.85, respectively) and severity (2.25 and 6.23, respectively) were acceptable. The Bland-Altman analysis for assessing the agreement between test and retest measurements showed no systematic bias. The VTDp is a valid and reliable self-administered scale to measure patient's vocal tract sensations in Persian-speaking population. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.
Numerical Study of Aeroacoustic Sound on Performance of Bladeless Fan
NASA Astrophysics Data System (ADS)
Jafari, Mohammad; Sojoudi, Atta; Hafezisefat, Parinaz
2017-03-01
Aeroacoustic performance of fans is essential due to their widespread application. Therefore, the original aim of this paper is to evaluate the generated noise owing to different geometric parameters. In current study, effect of five geometric parameters was investigated on well performance of a Bladeless fan. Airflow through this fan was analyzed simulating a Bladeless fan within a 2 m×2 m×4 m room. Analysis of the flow field inside the fan and evaluating its performance were obtained by solving conservations of mass and momentum equations for aerodynamic investigations and FW-H noise equations for aeroacoustic analysis. In order to design Bladeless fan Eppler 473 airfoil profile was used as the cross section of this fan. Five distinct parameters, namely height of cross section of the fan, outlet angle of the flow relative to the fan axis, thickness of airflow outlet slit, hydraulic diameter and aspect ratio for circular and quadratic cross sections were considered. Validating acoustic code results, we compared numerical solution of FW-H noise equations for NACA0012 with experimental results. FW-H model was selected to predict the noise generated by the Bladeless fan as the numerical results indicated a good agreement with experimental ones for NACA0012. To validate 3-D numerical results, the experimental results of a round jet showed good agreement with those simulation data. In order to indicate the effect of each mentioned parameter on the fan performance, SPL and OASPL diagrams were illustrated.
Measuring Adolescent Social and Academic Self-Efficacy: Cross-Ethnic Validity of the SEQ-C
ERIC Educational Resources Information Center
Minter, Anthony; Pritzker, Suzanne
2017-01-01
Objective: This study examines the psychometric strength, including cross-ethnic validity, of two subscales of Muris' Self-Efficacy Questionnaire for Children: Academic Self-Efficacy (ASE) and Social Self-Efficacy (SSE). Methods: A large ethnically diverse sample of 3,358 early and late adolescents completed surveys including the ASE and SSE.…
ERIC Educational Resources Information Center
Hilton, N. Zoe; Harris, Grant T.
2009-01-01
Prediction effect sizes such as ROC area are important for demonstrating a risk assessment's generalizability and utility. How a study defines recidivism might affect predictive accuracy. Nonrecidivism is problematic when predicting specialized violence (e.g., domestic violence). The present study cross-validates the ability of the Ontario…
USDA-ARS?s Scientific Manuscript database
Generalised skinfold equations developed in the 1970s are commonly used to estimate laboratory-measured percentage fat (BF%). The equations were developed on predominately white individuals using Siri's two-component percentage fat equation (BF%-GEN). We cross-validated the Jackson-Pollock (JP) gene...
ERIC Educational Resources Information Center
Yamkovenko, Bogdan V.; Holton, Elwood, III; Bates, R. A.
2007-01-01
Purpose: The purpose of this research is to expand cross-cultural research and validate the Learning Transfer System Inventory in Ukraine. The researchers seek to translate the LTSI into Ukrainian and investigate the internal structure of this translated version of the questionnaire. Design/methodology/approach: The LTSI is translated into…
Validation of annual growth rings in freshwater mussel shells using cross dating .Can
Andrew L. Rypel; Wendell R. Haag; Robert H. Findlay
2009-01-01
We examined the usefulness of dendrochronological cross-dating methods for studying long-term, interannual growth patterns in freshwater mussels, including validation of annual shell ring formation. Using 13 species from three rivers, we measured increment widths between putative annual rings on shell thin sections and then removed age-related variation by...
Cross-Cultural Validation of Stages of Exercise Change Scale among Chinese College Students
ERIC Educational Resources Information Center
Keating, Xiaofen D.; Guan, Jianmin; Huang, Yong; Deng, Mingying; Wu, Yifeng; Qu, Shuhua
2005-01-01
The purpose of the study was to test the cross-cultural concurrent validity of the stages of exercise change scale (SECS) in Chinese college students. The original SECS was translated into Chinese (C-SECS). Students from four Chinese universities (N = 1843) participated in the study. The leisure-time exercise (LTE) questionnaire was used to…
[Maslach Burnout Inventory - Student Survey: Portugal-Brazil cross-cultural adaptation].
Campos, Juliana Alvares Duarte Bonini; Maroco, João
2012-10-01
To perform a cross-cultural adaptation of the Portuguese version of the Maslach Burnout Inventory for students (MBI-SS), and investigate its reliability, validity and cross-cultural invariance. The face validity involved the participation of a multidisciplinary team. Content validity was performed. The Portuguese version was completed in 2009, on the internet, by 958 Brazilian and 556 Portuguese university students from the urban area. Confirmatory factor analysis was carried out using as fit indices: the χ²/df, the Comparative Fit Index (CFI), the Goodness of Fit Index (GFI) and the Root Mean Square Error of Approximation (RMSEA). To verify the stability of the factor solution according to the original English version, cross-validation was performed in 2/3 of the total sample and replicated in the remaining 1/3. Convergent validity was estimated by the average variance extracted and composite reliability. The discriminant validity was assessed, and the internal consistency was estimated by the Cronbach's alpha coefficient. Concurrent validity was estimated by the correlational analysis of the mean scores of the Portuguese version and the Copenhagen Burnout Inventory, and the divergent validity was compared to the Beck Depression Inventory. The invariance of the model between the Brazilian and the Portuguese samples was assessed. The three-factor model of Exhaustion, Disengagement and Efficacy showed good fit (c 2/df = 8.498, CFI = 0.916, GFI = 0.902, RMSEA = 0.086). The factor structure was stable (λ:χ²dif = 11.383, p = 0.50; Cov: χ²dif = 6.479, p = 0.372; Residues: χ²dif = 21.514, p = 0.121). Adequate convergent validity (VEM = 0.45;0.64, CC = 0.82;0.88), discriminant (ρ² = 0.06;0.33) and internal consistency (α = 0.83;0.88) were observed. The concurrent validity of the Portuguese version with the Copenhagen Inventory was adequate (r = 0.21, 0.74). The assessment of the divergent validity was impaired by the approach of the theoretical concept of the dimensions Exhaustion and Disengagement of the Portuguese version with the Beck Depression Inventory. Invariance of the instrument between the Brazilian and Portuguese samples was not observed (λ:χ²dif = 84.768, p<0.001; Cov: χ²dif = 129.206, p < 0.001; Residues: χ²dif = 518.760, p < 0.001). The Portuguese version of the Maslach Burnout Inventory for students showed adequate reliability and validity, but its factor structure was not invariant between the countries, indicating the absence of cross-cultural stability.
K-Fold Crossvalidation in Canonical Analysis.
ERIC Educational Resources Information Center
Liang, Kun-Hsia; And Others
1995-01-01
A computer-assisted, K-fold cross-validation technique is discussed in the framework of canonical correlation analysis of randomly generated data sets. Analysis results suggest that this technique can effectively reduce the contamination of canonical variates and canonical correlations by sample-specific variance components. (Author/SLD)
MODAS Validation in Littoral Areas Using GRASP
2002-09-30
result (4 hr) is guiding new work on calculation efficiency. Figure 4. Near-optimal coordinated passive search plan against a complex transitor ... Transitor tracks form a river of roughly parallel potential paths. The two searcher tracks criss- cross this river like shoe lacings over much of
Lanza, Ian R.; Bhagra, Sumit; Nair, K. Sreekumaran; Port, John D.
2011-01-01
Purpose To cross-validate skeletal muscle oxidative capacity measured by 31P-MRS with in vitro measurements of oxidative capacityin mitochondria isolated from muscle biopsies of the same muscle group in 18 healthy adults. Materials and Methods Oxidative capacity in vivo was determined from PCr recovery kinetics following a 30s maximal isometric knee extension. State 3 respiration was measured in isolated mitochondria using high-resolution respirometry. A second cohort of 10 individuals underwent two 31P-MRS testing sessions to assess the test-retest reproducibility of the method. Results Overall, the in vivo and in vitro methods were well-correlated (r = 0.66 –0.72) and showed good agreement by Bland Altman plots. Excellent reproducibility was observed for the PCr recovery rate constant (CV = 4.6%, ICC = 0.85) and calculated oxidative capacity (CV = 3.4%, ICC = 0.83). Conclusion These results indicate that 31P-MRS corresponds well with gold-standard in vitro measurements and is highly reproducible. PMID:22006551
Prediction of the space adaptation syndrome
NASA Technical Reports Server (NTRS)
Reschke, M. F.; Homick, J. L.; Ryan, P.; Moseley, E. C.
1984-01-01
The univariate and multivariate relationships of provocative measures used to produce motion sickness symptoms were described. Normative subjects were used to develop and cross-validate sets of linear equations that optimally predict motion sickness in parabolic flights. The possibility of reducing the number of measurements required for prediction was assessed. After describing the variables verbally and statistically for 159 subjects, a factor analysis of 27 variables was completed to improve understanding of the relationships between variables and to reduce the number of measures for prediction purposes. The results of this analysis show that none of variables are significantly related to the responses to parabolic flights. A set of variables was selected to predict responses to KC-135 flights. A series of discriminant analyses were completed. Results indicate that low, moderate, or severe susceptibility could be correctly predicted 64 percent and 53 percent of the time on original and cross-validation samples, respectively. Both the factor analysis and the discriminant analysis provided no basis for reducing the number of tests.
Combined 3D-QSAR modeling and molecular docking study on azacycles CCR5 antagonists
NASA Astrophysics Data System (ADS)
Ji, Yongjun; Shu, Mao; Lin, Yong; Wang, Yuanqiang; Wang, Rui; Hu, Yong; Lin, Zhihua
2013-08-01
The beta chemokine receptor 5 (CCR5) is an attractive target for pharmaceutical industry in the HIV-1, inflammation and cancer therapeutic areas. In this study, we have developed quantitative structure activity relationship (QSAR) models for a series of 41 azacycles CCR5 antagonists using comparative molecular field analysis (CoMFA), comparative molecular similarity indices analysis (CoMSIA), and Topomer CoMFA methods. The cross-validated coefficient q2 values of 3D-QASR (CoMFA, CoMSIA, and Topomer CoMFA) methods were 0.630, 0.758, and 0.852, respectively, the non-cross-validated R2 values were 0.979, 0.978, and 0.990, respectively. Docking studies were also employed to determine the most probable binding mode. 3D contour maps and docking results suggested that bulky groups and electron-withdrawing groups on the core part would decrease antiviral activity. Furthermore, docking results indicated that H-bonds and π bonds were favorable for antiviral activities. Finally, a set of novel derivatives with predicted activities were designed.
NASA Technical Reports Server (NTRS)
Colliander, Andreas; Kim, Seungbum; Yueh, Simon; Cosh, Mike; Jackson, Tom; Njoku, Eni
2010-01-01
Coincidental airborne brightness temperature (TB) and normalized radar-cross section (NRCS) measurements were carried out with the PALS (Passive and Active L- and S-band) instrument in the SMAPVEX08 (SMAP Validation Experiment 2008) field campaign. This paper describes results obtained from a set of flights which measured a field in 45(sup o) steps over the azimuth angle. The field contained mature soy beans with distinct row structure. The measurement shows that both TB and NRCS experience modulation effects over the azimuth as expected based on the theory. The result is useful in development and validation of land surface parameter forward models and retrieval algorithms, such as the soil moisture algorithm for NASA's SMAP (Soil Moisture Active and Passive) mission. Although the footprint of the SMAP will not be sensitive to the small resolution scale effects as the one presented in this paper, it is nevertheless important to understand the effects at smaller scale.
Predicting protein-binding regions in RNA using nucleotide profiles and compositions.
Choi, Daesik; Park, Byungkyu; Chae, Hanju; Lee, Wook; Han, Kyungsook
2017-03-14
Motivated by the increased amount of data on protein-RNA interactions and the availability of complete genome sequences of several organisms, many computational methods have been proposed to predict binding sites in protein-RNA interactions. However, most computational methods are limited to finding RNA-binding sites in proteins instead of protein-binding sites in RNAs. Predicting protein-binding sites in RNA is more challenging than predicting RNA-binding sites in proteins. Recent computational methods for finding protein-binding sites in RNAs have several drawbacks for practical use. We developed a new support vector machine (SVM) model for predicting protein-binding regions in mRNA sequences. The model uses sequence profiles constructed from log-odds scores of mono- and di-nucleotides and nucleotide compositions. The model was evaluated by standard 10-fold cross validation, leave-one-protein-out (LOPO) cross validation and independent testing. Since actual mRNA sequences have more non-binding regions than protein-binding regions, we tested the model on several datasets with different ratios of protein-binding regions to non-binding regions. The best performance of the model was obtained in a balanced dataset of positive and negative instances. 10-fold cross validation with a balanced dataset achieved a sensitivity of 91.6%, a specificity of 92.4%, an accuracy of 92.0%, a positive predictive value (PPV) of 91.7%, a negative predictive value (NPV) of 92.3% and a Matthews correlation coefficient (MCC) of 0.840. LOPO cross validation showed a lower performance than the 10-fold cross validation, but the performance remains high (87.6% accuracy and 0.752 MCC). In testing the model on independent datasets, it achieved an accuracy of 82.2% and an MCC of 0.656. Testing of our model and other state-of-the-art methods on a same dataset showed that our model is better than the others. Sequence profiles of log-odds scores of mono- and di-nucleotides were much more powerful features than nucleotide compositions in finding protein-binding regions in RNA sequences. But, a slight performance gain was obtained when using the sequence profiles along with nucleotide compositions. These are preliminary results of ongoing research, but demonstrate the potential of our approach as a powerful predictor of protein-binding regions in RNA. The program and supporting data are available at http://bclab.inha.ac.kr/RBPbinding .
Moreira, Sérgio; Carreiras, Joana; Cooper, Cary; Smeed, Matthew; Reis, Maria de Fátima; Pereira Miguel, José
2018-01-01
Objective The main objective of this work was to translate the English version of ASSET (A Shortened Stress Evaluation Tool) into the Portuguese version and to validate its psychometric properties. Additionally, this work tested the convergent validity of the instrument. Methods The translation and retroversion were conducted by experts and submitted to the authors for approval. Within an observational, cross-sectional study, regarding mental health at the workplace, ASSET together with other scales was applied to a sample of 405 participants. The psychometric validity of the subscales was studied using confirmatory factorial analysis. Results The factorial structure of ASSET is globally supported by the results, with the Perceptions of Your Job and Attitudes Towards your Organisation subscales requiring slight adjustments in the item structure and the Your Health subscales replicating the original structure. The convergent validity also supports the ASSET, showing that all subscales are significantly correlated with variables used to test convergence. Conclusions Globally, the results constitute an important contribution to ASSET and open the possibility of its usage among Portuguese-speaking countries. The results provide an evidence on the validity of the instrument and, in particular, of the mental and physical health subscales. PMID:29440211
Progress on China nuclear data processing code system
NASA Astrophysics Data System (ADS)
Liu, Ping; Wu, Xiaofei; Ge, Zhigang; Li, Songyang; Wu, Haicheng; Wen, Lili; Wang, Wenming; Zhang, Huanyu
2017-09-01
China is developing the nuclear data processing code Ruler, which can be used for producing multi-group cross sections and related quantities from evaluated nuclear data in the ENDF format [1]. The Ruler includes modules for reconstructing cross sections in all energy range, generating Doppler-broadened cross sections for given temperature, producing effective self-shielded cross sections in unresolved energy range, calculating scattering cross sections in thermal energy range, generating group cross sections and matrices, preparing WIMS-D format data files for the reactor physics code WIMS-D [2]. Programming language of the Ruler is Fortran-90. The Ruler is tested for 32-bit computers with Windows-XP and Linux operating systems. The verification of Ruler has been performed by comparison with calculation results obtained by the NJOY99 [3] processing code. The validation of Ruler has been performed by using WIMSD5B code.
Universal Parameterization of Absorption Cross Sections
NASA Technical Reports Server (NTRS)
Tripathi, R. K.; Cucinotta, Francis A.; Wilson, John W.
1997-01-01
This paper presents a simple universal parameterization of total reaction cross sections for any system of colliding nuclei that is valid for the entire energy range from a few AMeV to a few AGeV. The universal picture presented here treats proton-nucleus collision as a special case of nucleus-nucleus collision, where the projectile has charge and mass number of one. The parameters are associated with the physics of the collision system. In general terms, Coulomb interaction modifies cross sections at lower energies, and the effects of Pauli blocking are important at higher energies. The agreement between the calculated and experimental data is better than all earlier published results.
Stevanovic, Dejan; Jafari, Peyman; Knez, Rajna; Franic, Tomislav; Atilola, Olayinka; Davidovic, Nikolina; Bagheri, Zahra; Lakic, Aneta
2017-02-01
In this systematic review, we assessed available evidence for cross-cultural measurement invariance of assessment scales for child and adolescent psychopathology as an indicator of cross-cultural validity. A literature search was conducted using the Medline, PsychInfo, Scopus, Web of Science, and Google Scholar databases. Cross-cultural measurement invariance data was available for 26 scales. Based on the aggregation of the evidence from the studies under review, none of the evaluated scales have strong evidence for cross-cultural validity and suitability for cross-cultural comparison. A few of the studies showed a moderate level of measurement invariance for some scales (such as the Fear Survey Schedule for Children-Revised, Multidimensional Anxiety Scale for Children, Revised Child Anxiety and Depression Scale, Revised Children's Manifest Anxiety Scale, Mood and Feelings Questionnaire, and Disruptive Behavior Rating Scale), which may make them suitable in cross-cultural comparative studies. The remainder of the scales either showed weak or outright lack of measurement invariance. This review showed only limited testing for measurement invariance across cultural groups of scales for pediatric psychopathology, with evidence of cross-cultural validity for only a few scales. This study also revealed a need to improve practices of statistical analysis reporting in testing measurement invariance. Implications for future research are discussed.
Determination of fat and total protein content in milk using conventional digital imaging.
Kucheryavskiy, Sergey; Melenteva, Anastasiia; Bogomolov, Andrey
2014-04-01
The applicability of conventional digital imaging to quantitative determination of fat and total protein in cow's milk, based on the phenomenon of light scatter, has been proved. A new algorithm for extracting features from digital images of milk samples has been developed. The algorithm takes into account spatial distribution of light, diffusely transmitted through a sample. The proposed method has been tested on two sample sets prepared from industrial raw milk standards, with variable fat and protein content. Partial Least-Squares (PLS) regression on the features calculated from images of monochromatically illuminated milk samples resulted in models with high prediction performance when analysed the sets separately (best models with cross-validated R(2)=0.974 for protein and R(2)=0.973 for fat content). However when analysed the sets jointly with the obtained results were significantly worse (best models with cross-validated R(2)=0.890 for fat content and R(2)=0.720 for protein content). The results have been compared with previously published Vis/SW-NIR spectroscopic study of similar samples. Copyright © 2013 Elsevier B.V. All rights reserved.
Ahmetovic, Dragan; Manduchi, Roberto; Coughlan, James M.; Mascetti, Sergio
2016-01-01
In this paper we propose a computer vision-based technique that mines existing spatial image databases for discovery of zebra crosswalks in urban settings. Knowing the location of crosswalks is critical for a blind person planning a trip that includes street crossing. By augmenting existing spatial databases (such as Google Maps or OpenStreetMap) with this information, a blind traveler may make more informed routing decisions, resulting in greater safety during independent travel. Our algorithm first searches for zebra crosswalks in satellite images; all candidates thus found are validated against spatially registered Google Street View images. This cascaded approach enables fast and reliable discovery and localization of zebra crosswalks in large image datasets. While fully automatic, our algorithm could also be complemented by a final crowdsourcing validation stage for increased accuracy. PMID:26824080
NASA Astrophysics Data System (ADS)
Syha, M.; Rheinheimer, W.; Loedermann, B.; Graff, A.; Trenkle, A.; Baeurer, M.; Weygand, D.; Ludwig, W.; Gumbsch, P.
The microstructural evolution of polycrystalline strontium titanate was investigated in three dimensions (3D) using X-ray diffraction contrast tomography (DCT) before and after ex-situ annealing at 1600°C. Post-annealing, the specimen was additionally subjected to phase contrast tomography (PCT) in order to finely resolve the porosities. The resulting microstructure reconstructions were studied with special emphasis on morphology and interface orientation during microstructure evolution. Subsequently, cross-sections of the specimen were studied using electron backscatter diffraction (EBSD). Corresponding cross-sections through the 3D reconstruction were identified and the quality of the reconstruction is validated with special emphasis on the spatial resolution at the grain boundaries, the size and location of pores contained in the material and the accuracy of the orientation determination.
Shapira Galitz, Yael; Halperin, Doron; Bavnik, Yosef; Warman, Meir
2016-05-01
To perform the translation, cross-cultural adaptation, and validation of the Sino-Nasal Outcome Test-22 (SNOT-22) questionnaire to the Hebrew language. A single-center prospective cross-sectional study. Seventy-three chronic rhinosinusitis (CRS) patients and 73 patients without sinonasal disease filled the Hebrew version of the SNOT-22 questionnaire. Fifty-one CRS patients underwent endoscopic sinus surgery, out of which 28 filled a postoperative questionnaire. Seventy-three healthy volunteers without sinonasal disease also answered the questionnaire. Internal consistency, test-retest reproducibility, validity, and responsiveness of the questionnaire were evaluated. Questionnaire reliability was excellent, with a high internal consistency (Cronbach's alpha coefficient, 0.91-0.936) and test-retest reproducibility (Spearman's coefficient, 0.962). Mean scores for the preoperative, postoperative, and control groups were 50.44, 29.64, and 13.15, respectively (P < .0001 for CRS vs controls, P < .001 for preoperative vs postoperative), showing validity and responsiveness of the questionnaire. The Hebrew version of SNOT-22 questionnaire is a valid outcome measure for patients with CRS with or without nasal polyps. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.
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.
Algorithm research for user trajectory matching across social media networks based on paragraph2vec
NASA Astrophysics Data System (ADS)
Xu, Qian; Chen, Hongchang; Zhi, Hongxin; Wang, Yanchuan
2018-04-01
Identifying users across different social media networks (SMN) is to link accounts of the same user that belong to the same individual across SMNs. The problem is fundamental and important, and its results can benefit many applications such as cross SMN user modeling and recommendation. With the development of GPS technology and mobile communication, more and more social networks provide location services. This provides a new opportunity for cross SMN user identification. In this paper, we solve cross SMN user identification problem in an unsupervised manner by utilizing user trajectory data in SMNs. A paragraph2vec based algorithm is proposed in which location sequence feature of user trajectory is captured in temporal and spatial dimensions. Our experimental results validate the effectiveness and efficiency of our algorithm.
Digitized Spiral Drawing: A Possible Biomarker for Early Parkinson’s Disease
San Luciano, Marta; Wang, Cuiling; Ortega, Roberto A.; Yu, Qiping; Boschung, Sarah; Soto-Valencia, Jeannie; Bressman, Susan B.; Lipton, Richard B.; Pullman, Seth; Saunders-Pullman, Rachel
2016-01-01
Introduction Pre-clinical markers of Parkinson’s Disease (PD) are needed, and to be relevant in pre-clinical disease, they should be quantifiably abnormal in early disease as well. Handwriting is impaired early in PD and can be evaluated using computerized analysis of drawn spirals, capturing kinematic, dynamic, and spatial abnormalities and calculating indices that quantify motor performance and disability. Digitized spiral drawing correlates with motor scores and may be more sensitive in detecting early changes than subjective ratings. However, whether changes in spiral drawing are abnormal compared with controls and whether changes are detected in early PD are unknown. Methods 138 PD subjects (50 with early PD) and 150 controls drew spirals on a digitizing tablet, generating x, y, z (pressure) data-coordinates and time. Derived indices corresponded to overall spiral execution (severity), shape and kinematic irregularity (second order smoothness, first order zero-crossing), tightness, mean speed and variability of spiral width. Linear mixed effect adjusted models comparing these indices and cross-validation were performed. Receiver operating characteristic analysis was applied to examine discriminative validity of combined indices. Results All indices were significantly different between PD cases and controls, except for zero-crossing. A model using all indices had high discriminative validity (sensitivity = 0.86, specificity = 0.81). Discriminative validity was maintained in patients with early PD. Conclusion Spiral analysis accurately discriminates subjects with PD and early PD from controls supporting a role as a promising quantitative biomarker. Further assessment is needed to determine whether spiral changes are PD specific compared with other disorders and if present in pre-clinical PD. PMID:27732597
Development and initial validation of a short three-dimensional inventory of character strengths.
Duan, Wenjie; Bu, He
2017-09-01
Character strength is described as a positive and organized pattern of emotions, thoughts, and behaviors. It serves as a schema that organizes categories of information toward the self, others, and the world, and provides the self-aware knowledge that facilitates the pursuit of goals, values, and ethical principles. Recent research has suggested that three reliable factors emerge from the measures of character strengths: caring, inquisitiveness, and self-control. The goal of this paper is to develop a psychometrically sound short measure of character strength. The questions were addressed in two studies using two independent samples: a cross-cultural (i.e., 518 Asians and 556 Westerners) sample, and a cross-population (i.e., 175 community participants and 171 inpatients) sample in China. Findings from the exploratory and confirmatory factor analysis suggested a cross-cultural three-factor model of character strength that could be measured by the Three-dimensional Inventory of Character Strengths (TICS). A multigroup confirmatory factor analysis further indicated that the number of factors and factor loadings was invariant in the medical and community samples. This result indicated that the brief inventory could be applied to a medical context. Internal reliability, content validity, and predictive validity were good, although the predictive validity of the three character strengths for psychological symptoms in the medical sample was more modest than that in the community sample. TICS is expected to be used for screening populations at risk, and a tool to aid mental health professionals in group-based treatment/intervention planning. It also should be noted that this short inventory should be used with caution for individual decision making.
Vork, L; Keszthelyi, D; Mujagic, Z; Kruimel, J W; Leue, C; Pontén, I; Törnblom, H; Simrén, M; Albu-Soda, A; Aziz, Q; Corsetti, M; Holvoet, L; Tack, J; Rao, S S; van Os, J; Quetglas, E G; Drossman, D A; Masclee, A A M
2018-03-01
End-of-day questionnaires, which are considered the gold standard for assessing abdominal pain and other gastrointestinal (GI) symptoms in irritable bowel syndrome (IBS), are influenced by recall and ecological bias. The experience sampling method (ESM) is characterized by random and repeated assessments in the natural state and environment of a subject, and herewith overcomes these limitations. This report describes the development of a patient-reported outcome measure (PROM) based on the ESM principle, taking into account content validity and cross-cultural adaptation. Focus group interviews with IBS patients and expert meetings with international experts in the fields of neurogastroenterology & motility and pain were performed in order to select the items for the PROM. Forward-and-back translation and cognitive interviews were performed to adapt the instrument for the use in different countries and to assure on patients' understanding with the final items. Focus group interviews revealed 42 items, categorized into five domains: physical status, defecation, mood and psychological factors, context and environment, and nutrition and drug use. Experts reduced the number of items to 32 and cognitive interviewing after translation resulted in a few slight adjustments regarding linguistic issues, but not regarding content of the items. An ESM-based PROM, suitable for momentary assessment of IBS symptom patterns was developed, taking into account content validity and cross-cultural adaptation. This PROM will be implemented in a specifically designed smartphone application and further validation in a multicenter setting will follow. © 2017 John Wiley & Sons Ltd.
Jalenques, I; Auclair, C; Roblin, J; Morand, D; Tourtauchaux, R; May, R; Vaille-Perret, E; Watts, J; Gerbaud, L; De Leo, D
2013-04-01
To cross-culturally adapt a French version of the LEIPAD, a self-administered questionnaire assessing the health-related quality of life (HRQoL) in adults aged 65 years and over living at home, and to evaluate its psychometric properties. After having translated LEIPAD in accordance with guidelines, we studied psychometric properties: reliability and construct validity-factor analysis, relationships between items and scales, internal consistency, concurrent validity with the Medical Outcome Study Short-Form 36 and known-groups validity. The results obtained in a sample of 195 elderly from the general population showed very good acceptability, with response rates superior to 93 %. Exploratory factor analysis extracted eight factors providing a multidimensionality structure with five misclassifications of items in the seven theoretical scales. Good internal consistency (Cronbach's alpha ranging from 0.73 and 0.86) and strong test-retest reliability (ICCs higher than 0.80 for six scales and 0.70 for one) were demonstrated. Concurrent validity with the SF-36 showed small to strong expected correlations. This first evaluation of the French version of LEIPAD's psychometric properties provides evidence in construct validity and reliability. It would allow HRQoL assessment in clinical and common practice, and investigators would be able to take part in national and international research projects.
Kim, Jin Goo; Lee, Joong Yub; Seo, Seung Suk; Choi, Choong Hyeok; Lee, Myung Chul
2013-01-01
Purpose To perform a cross-cultural adaptation and to test the measurement properties of the Korean version of International Knee Documentation Committee (K-IKDC) Subjective Knee Form. Materials and Methods According to the guidelines for cross-cultural adaptation, translation and backward translation of the English version of the IKDC Subjective Knee Form were performed. After translation into the Korean version, 150 patients who had knee-related problems were asked to complete the K-IKDC, Lysholm score, and Short Form-36 (SF-36). Of these patients, 126 were retested 2 weeks later to evaluate test-retest reliability, and 104 were recruited 3 months later to evaluate responsiveness. Construct validity was analyzed by investigating the correlation with Lysholm score and SF-36; content validity was also evaluated. Standardized mean response was calculated for evaluating responsiveness. Results The test-retest reliability proved excellent with a high value for the intraclass correlation coefficient (r=0.94). The internal consistency was strong (Cronbach's α=0.91). Good content validity with absence of floor not ceiling effects and good convergent and divergent validity were observed. Moderate responsiveness was shown (standardized mean response=0.689). Conclusions The K-IKDC demonstrated good measurement properties. We suggest that this instrument is an excellent evaluation instrument that can be used for Korean patients with knee-related injuries. PMID:24032098
Verloo, Henk; Desmedt, Mario; Morin, Diane
2017-09-01
To evaluate two psychometric properties of the French versions of the Evidence-Based Practice Beliefs and Evidence-Based Practice Implementation scales, namely their internal consistency and construct validity. The Evidence-Based Practice Beliefs and Evidence-Based Practice Implementation scales developed by Melnyk et al. are recognised as valid, reliable instruments in English. However, no psychometric validation for their French versions existed. Secondary analysis of a cross sectional survey. Source data came from a cross-sectional descriptive study sample of 382 nurses and other allied healthcare providers. Cronbach's alpha was used to evaluate internal consistency, and principal axis factor analysis and varimax rotation were computed to determine construct validity. The French Evidence-Based Practice Beliefs and Evidence-Based Practice Implementation scales showed excellent reliability, with Cronbach's alphas close to the scores established by Melnyk et al.'s original versions. Principal axis factor analysis showed medium-to-high factor loading scores without obtaining collinearity. Principal axis factor analysis with varimax rotation of the 16-item Evidence-Based Practice Beliefs scale resulted in a four-factor loading structure. Principal axis factor analysis with varimax rotation of the 17-item Evidence-Based Practice Implementation scale revealed a two-factor loading structure. Further research should attempt to understand why the French Evidence-Based Practice Implementation scale showed a two-factor loading structure but Melnyk et al.'s original has only one. The French versions of the Evidence-Based Practice Beliefs and Evidence-Based Practice Implementation scales can both be considered valid and reliable instruments for measuring Evidence-Based Practice beliefs and implementation. The results suggest that the French Evidence-Based Practice Beliefs and Evidence-Based Practice Implementation scales are valid and reliable and can therefore be used to evaluate the effectiveness of organisational strategies aimed at increasing professionals' confidence in Evidence-Based Practice, supporting its use and implementation. © 2017 John Wiley & Sons Ltd.
Tsugawa, Yusuke; Ohbu, Sadayoshi; Cruess, Richard; Cruess, Sylvia; Okubo, Tomoya; Takahashi, Osamu; Tokuda, Yasuharu; Heist, Brian S; Bito, Seiji; Itoh, Toshiyuki; Aoki, Akiko; Chiba, Tsutomu; Fukui, Tsuguya
2011-08-01
Despite the growing importance of and interest in medical professionalism, there is no standardized tool for its measurement. The authors sought to verify the validity, reliability, and generalizability of the Professionalism Mini-Evaluation Exercise (P-MEX), a previously developed and tested tool, in the context of Japanese hospitals. A multicenter, cross-sectional evaluation study was performed to investigate the validity, reliability, and generalizability of the P-MEX in seven Japanese hospitals. In 2009-2010, 378 evaluators (attending physicians, nurses, peers, and junior residents) completed 360-degree assessments of 165 residents and fellows using the P-MEX. The content validity and criterion-related validity were examined, and the construct validity of the P-MEX was investigated by performing confirmatory factor analysis through a structural equation model. The reliability was tested using generalizability analysis. The contents of the P-MEX achieved good acceptance in a preliminary working group, and the poststudy survey revealed that 302 (79.9%) evaluators rated the P-MEX items as appropriate, indicating good content validity. The correlation coefficient between P-MEX scores and external criteria was 0.78 (P < .001), demonstrating good criterion-related validity. Confirmatory factor analysis verified high path coefficient (0.60-0.99) and adequate goodness of fit of the model. The generalizability analysis yielded a high dependability coefficient, suggesting good reliability, except when evaluators were peers or junior residents. Findings show evidence of adequate validity, reliability, and generalizability of the P-MEX in Japanese hospital settings. The P-MEX is the only evaluation tool for medical professionalism verified in both a Western and East Asian cultural context.
Validation of Yoon's Critical Thinking Disposition Instrument.
Shin, Hyunsook; Park, Chang Gi; Kim, Hyojin
2015-12-01
The lack of reliable and valid evaluation tools targeting Korean nursing students' critical thinking (CT) abilities has been reported as one of the barriers to instructing and evaluating students in undergraduate programs. Yoon's Critical Thinking Disposition (YCTD) instrument was developed for Korean nursing students, but few studies have assessed its validity. This study aimed to validate the YCTD. Specifically, the YCTD was assessed to identify its cross-sectional and longitudinal measurement invariance. This was a validation study in which a cross-sectional and longitudinal (prenursing and postnursing practicum) survey was used to validate the YCTD using 345 nursing students at three universities in Seoul, Korea. The participants' CT abilities were assessed using the YCTD before and after completing an established pediatric nursing practicum. The validity of the YCTD was estimated and then group invariance test using multigroup confirmatory factor analysis was performed to confirm the measurement compatibility of multigroups. A test of the seven-factor model showed that the YCTD demonstrated good construct validity. Multigroup confirmatory factor analysis findings for the measurement invariance suggested that this model structure demonstrated strong invariance between groups (i.e., configural, factor loading, and intercept combined) but weak invariance within a group (i.e., configural and factor loading combined). In general, traditional methods for assessing instrument validity have been less than thorough. In this study, multigroup confirmatory factor analysis using cross-sectional and longitudinal measurement data allowed validation of the YCTD. This study concluded that the YCTD can be used for evaluating Korean nursing students' CT abilities. Copyright © 2015. Published by Elsevier B.V.
Detection of Malingered Mental Retardation
ERIC Educational Resources Information Center
Shandera, Anne L.; Berry, David T. R.; Clark, Jessica A.; Schipper, Lindsey J.; Graue, Lili O.; Harp, Jordan P.
2010-01-01
In a cross-validation of results from L. O. Graue et al. (2007), standard psychological assessment instruments, as well as tests of neurocognitive and psychiatric feigning, were administered under standard instructions to 24 participants diagnosed with mild mental retardation (MR) and 10 demographically matched community volunteers (CVH). A 2nd…
Desiderata: Towards Indigenous Models of Vocational Psychology
ERIC Educational Resources Information Center
Leong, Frederick T. L.; Pearce, Marina
2011-01-01
As a result of a relative lack of cross-cultural validity in most current (Western) psychological models, indigenous models of psychology have recently become a popular approach for understanding behaviour in specific cultures. Such models would be valuable to vocational psychology research with culturally diverse populations. Problems facing…
Environment and Teacher Interpersonal Behaviour in Secondary Science Classes in Korea.
ERIC Educational Resources Information Center
Kim, Heui-Baik; Fisher, Darrell L.; Fraser, Barry J.
2000-01-01
Studied classroom learning environment and teacher behavior in 12 Korean schools through questionnaires administered to 543 eighth graders. Results, which support the cross-cultural validity of both measures, show positive relationships between classroom environment and interpersonal teacher behavior and students' attitudinal outcome. Boys…
Veit, Johannes; Sachsenberg, Timo; Chernev, Aleksandar; Aicheler, Fabian; Urlaub, Henning; Kohlbacher, Oliver
2016-09-02
Modern mass spectrometry setups used in today's proteomics studies generate vast amounts of raw data, calling for highly efficient data processing and analysis tools. Software for analyzing these data is either monolithic (easy to use, but sometimes too rigid) or workflow-driven (easy to customize, but sometimes complex). Thermo Proteome Discoverer (PD) is a powerful software for workflow-driven data analysis in proteomics which, in our eyes, achieves a good trade-off between flexibility and usability. Here, we present two open-source plugins for PD providing additional functionality: LFQProfiler for label-free quantification of peptides and proteins, and RNP(xl) for UV-induced peptide-RNA cross-linking data analysis. LFQProfiler interacts with existing PD nodes for peptide identification and validation and takes care of the entire quantitative part of the workflow. We show that it performs at least on par with other state-of-the-art software solutions for label-free quantification in a recently published benchmark ( Ramus, C.; J. Proteomics 2016 , 132 , 51 - 62 ). The second workflow, RNP(xl), represents the first software solution to date for identification of peptide-RNA cross-links including automatic localization of the cross-links at amino acid resolution and localization scoring. It comes with a customized integrated cross-link fragment spectrum viewer for convenient manual inspection and validation of the results.
Cross-cultural validation of Lupus Impact Tracker in five European clinical practice settings.
Schneider, Matthias; Mosca, Marta; Pego-Reigosa, José-Maria; Gunnarsson, Iva; Maurel, Frédérique; Garofano, Anna; Perna, Alessandra; Porcasi, Rolando; Devilliers, Hervé
2017-05-01
The aim was to evaluate the cross-cultural validity of the Lupus Impact Tracker (LIT) in five European countries and to assess its acceptability and feasibility from the patient and physician perspectives. A prospective, observational, cross-sectional and multicentre validation study was conducted in clinical settings. Before the visit, patients completed LIT, Short Form 36 (SF-36) and care satisfaction questionnaires. During the visit, physicians assessed disease activity [Safety of Estrogens in Lupus Erythematosus National Assessment (SELENA)-SLEDAI], organ damage [SLICC/ACR damage index (SDI)] and flare occurrence. Cross-cultural validity was assessed using the Differential Item Functioning method. Five hundred and sixty-nine SLE patients were included by 25 specialists; 91.7% were outpatients and 89.9% female, with mean age 43.5 (13.0) years. Disease profile was as follows: 18.3% experienced flares; mean SELENA-SLEDAI score 3.4 (4.5); mean SDI score 0.8 (1.4); and SF-36 mean physical and mental component summary scores: physical component summary 42.8 (10.8) and mental component summary 43.0 (12.3). Mean LIT score was 34.2 (22.3) (median: 32.5), indicating that lupus moderately impacted patients' daily life. A cultural Differential Item Functioning of negligible magnitude was detected across countries (pseudo- R 2 difference of 0.01-0.04). Differences were observed between LIT scores and Physician Global Assessment, SELENA-SLEDAI, SDI scores = 0 (P < 0.035) and absence of flares (P = 0.004). The LIT showed a strong association with SF-36 physical and social role functioning, vitality, bodily pain and mental health (P < 0.001). The LIT was well accepted by patients and physicians. It was reliable, with Cronbach α coefficients ranging from 0.89 to 0.92 among countries. The LIT is validated in the five participating European countries. The results show its reliability and cultural invariability across countries. They suggest that LIT can be used in routine clinical practice to evaluate and follow patient-reported outcomes in order to improve patient-physician interaction. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com
Genomic prediction of reproduction traits for Merino sheep.
Bolormaa, S; Brown, D J; Swan, A A; van der Werf, J H J; Hayes, B J; Daetwyler, H D
2017-06-01
Economically important reproduction traits in sheep, such as number of lambs weaned and litter size, are expressed only in females and later in life after most selection decisions are made, which makes them ideal candidates for genomic selection. Accurate genomic predictions would lead to greater genetic gain for these traits by enabling accurate selection of young rams with high genetic merit. The aim of this study was to design and evaluate the accuracy of a genomic prediction method for female reproduction in sheep using daughter trait deviations (DTD) for sires and ewe phenotypes (when individual ewes were genotyped) for three reproduction traits: number of lambs born (NLB), litter size (LSIZE) and number of lambs weaned. Genomic best linear unbiased prediction (GBLUP), BayesR and pedigree BLUP analyses of the three reproduction traits measured on 5340 sheep (4503 ewes and 837 sires) with real and imputed genotypes for 510 174 SNPs were performed. The prediction of breeding values using both sire and ewe trait records was validated in Merino sheep. Prediction accuracy was evaluated by across sire family and random cross-validations. Accuracies of genomic estimated breeding values (GEBVs) were assessed as the mean Pearson correlation adjusted by the accuracy of the input phenotypes. The addition of sire DTD into the prediction analysis resulted in higher accuracies compared with using only ewe records in genomic predictions or pedigree BLUP. Using GBLUP, the average accuracy based on the combined records (ewes and sire DTD) was 0.43 across traits, but the accuracies varied by trait and type of cross-validations. The accuracies of GEBVs from random cross-validations (range 0.17-0.61) were higher than were those from sire family cross-validations (range 0.00-0.51). The GEBV accuracies of 0.41-0.54 for NLB and LSIZE based on the combined records were amongst the highest in the study. Although BayesR was not significantly different from GBLUP in prediction accuracy, it identified several candidate genes which are known to be associated with NLB and LSIZE. The approach provides a way to make use of all data available in genomic prediction for traits that have limited recording. © 2017 Stichting International Foundation for Animal Genetics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chapman, Bryan Scott; MacQuigg, Michael Robert; Wysong, Andrew Russell
In this document, the code MCNP is validated with ENDF/B-VII.1 cross section data under the purview of ANSI/ANS-8.24-2007, for use with uranium systems. MCNP is a computer code based on Monte Carlo transport methods. While MCNP has wide reading capability in nuclear transport simulation, this validation is limited to the functionality related to neutron transport and calculation of criticality parameters such as k eff.
ERIC Educational Resources Information Center
Zeidner, Moshe
1987-01-01
This study examined the cross-cultural validity of the sex bias contention with respect to standardized aptitude testing, used for academic prediction purposes in Israel. Analyses were based on the grade point average and scores of 1778 Jewish and 1017 Arab students who were administered standardized college entrance test batteries. (Author/LMO)
ERIC Educational Resources Information Center
Wang, Jessica; Lee, Li-Ching; Chen, Ying-Sheue; Hsu, Ju-Wei
2012-01-01
The cross-cultural validity of the Mandarin-adaptation of the social responsiveness scale (SRS) was examined in a sample of N = 307 participants in Taiwan, 140 typically developing and 167 with clinically-diagnosed developmental disorders. This scale is an autism assessment tool that provides a quantitative rather than categorical measure of…
USDA-ARS?s Scientific Manuscript database
Accurate, nonintrusive, and inexpensive techniques are needed to measure energy expenditure (EE) in free-living populations. Our primary aim in this study was to validate cross-sectional time series (CSTS) and multivariate adaptive regression splines (MARS) models based on observable participant cha...
Bajoub, Aadil; Medina-Rodríguez, Santiago; Ajal, El Amine; Cuadros-Rodríguez, Luis; Monasterio, Romina Paula; Vercammen, Joeri; Fernández-Gutiérrez, Alberto; Carrasco-Pancorbo, Alegría
2018-04-01
Selected Ion flow tube mass spectrometry (SIFT-MS) in combination with chemometrics was used to authenticate the geographical origin of Mediterranean virgin olive oils (VOOs) produced under geographical origin labels. In particular, 130 oil samples from six different Mediterranean regions (Kalamata (Greece); Toscana (Italy); Meknès and Tyout (Morocco); and Priego de Córdoba and Baena (Spain)) were considered. The headspace volatile fingerprints were measured by SIFT-MS in full scan with H 3 O + , NO + and O 2 + as precursor ions and the results were subjected to chemometric treatments. Principal Component Analysis (PCA) was used for preliminary multivariate data analysis and Partial Least Squares-Discriminant Analysis (PLS-DA) was applied to build different models (considering the three reagent ions) to classify samples according to the country of origin and regions (within the same country). The multi-class PLS-DA models showed very good performance in terms of fitting accuracy (98.90-100%) and prediction accuracy (96.70-100% accuracy for cross validation and 97.30-100% accuracy for external validation (test set)). Considering the two-class PLS-DA models, the one for the Spanish samples showed 100% sensitivity, specificity and accuracy in calibration, cross validation and external validation; the model for Moroccan oils also showed very satisfactory results (with perfect scores for almost every parameter in all the cases). Copyright © 2017 Elsevier Ltd. All rights reserved.
Windhausen, Vanessa S; Atlin, Gary N; Hickey, John M; Crossa, Jose; Jannink, Jean-Luc; Sorrells, Mark E; Raman, Babu; Cairns, Jill E; Tarekegne, Amsal; Semagn, Kassa; Beyene, Yoseph; Grudloyma, Pichet; Technow, Frank; Riedelsheimer, Christian; Melchinger, Albrecht E
2012-11-01
Genomic prediction is expected to considerably increase genetic gains by increasing selection intensity and accelerating the breeding cycle. In this study, marker effects estimated in 255 diverse maize (Zea mays L.) hybrids were used to predict grain yield, anthesis date, and anthesis-silking interval within the diversity panel and testcross progenies of 30 F(2)-derived lines from each of five populations. Although up to 25% of the genetic variance could be explained by cross validation within the diversity panel, the prediction of testcross performance of F(2)-derived lines using marker effects estimated in the diversity panel was on average zero. Hybrids in the diversity panel could be grouped into eight breeding populations differing in mean performance. When performance was predicted separately for each breeding population on the basis of marker effects estimated in the other populations, predictive ability was low (i.e., 0.12 for grain yield). These results suggest that prediction resulted mostly from differences in mean performance of the breeding populations and less from the relationship between the training and validation sets or linkage disequilibrium with causal variants underlying the predicted traits. Potential uses for genomic prediction in maize hybrid breeding are discussed emphasizing the need of (1) a clear definition of the breeding scenario in which genomic prediction should be applied (i.e., prediction among or within populations), (2) a detailed analysis of the population structure before performing cross validation, and (3) larger training sets with strong genetic relationship to the validation set.
Vogel, David L; Armstrong, Patrick Ian; Tsai, Pei-Chun; Wade, Nathaniel G; Hammer, Joseph H; Efstathiou, Georgios; Holtham, Elizabeth; Kouvaraki, Elli; Liao, Hsin-Ya; Shechtman, Zipora; Topkaya, Nursel
2013-04-01
Researchers have found that the stigma associated with seeking therapy--particularly self-stigma--can inhibit the use of psychological services. Yet, most of the research on self-stigma has been conducted in the United States. This is a considerable limitation, as the role of self-stigma in the help-seeking process may vary across cultural groups. However, to examine cross-cultural variations, researchers must first develop culturally valid scales. Therefore, this study examined scale validity and reliability of the widely used Self-Stigma of Seeking Help scale (SSOSH; Vogel, Wade, & Haake, 2006) across samples from 6 different countries (England, Greece, Israel, Taiwan, Turkey, and the United States). Specifically, we used a confirmatory factor analysis framework to conduct measurement invariance analysis and latent mean comparisons of the SSOSH across the 6 sampled countries. Overall, the results suggested that the SSOSH has a similar univariate structure across countries and is sufficiently invariant across countries to be used to explore cultural differences in the way that self-stigma relates to help-seeking behavior.
Maïano, Christophe; Morin, Alexandre J S; Probst, Michel
2015-09-01
The study tested the cross-linguistic validity of the Very Short form of the Physical Self-Inventory (PSI-VS) among 1115 Flemish (Dutch version) adolescents, and a comparison sample of 1103 French adolescents (French version; from Morin & Maïano, 2011a). Flemish adolescents also completed a positively worded reformulation of the reverse-keyed item of the physical attractiveness (PA) subscale. Confirmatory factor analyses (CFA) supported the factor validity and reliability (except for the Dutch PA subscale) of the PSI-VS, and its partial measurement invariance across samples. CFA conducted on the modified version of the Dutch PSI-VS (11 original items plus the positively worded replacement), presented satisfactory reliability (ω=.67-.89), and was fully invariant across sexes, age groups, and body mass index categories. Additionally, results revealed latent mean differences across sexes and body mass index categories. Therefore, the modified Dutch PSI-VS can be used whenever there is a need for a very short physical self-concept questionnaire. Copyright © 2015 Elsevier Ltd. All rights reserved.
Near infrared spectroscopy for prediction of antioxidant compounds in the honey.
Escuredo, Olga; Seijo, M Carmen; Salvador, Javier; González-Martín, M Inmaculada
2013-12-15
The selection of antioxidant variables in honey is first time considered applying the near infrared (NIR) spectroscopic technique. A total of 60 honey samples were used to develop the calibration models using the modified partial least squares (MPLS) regression method and 15 samples were used for external validation. Calibration models on honey matrix for the estimation of phenols, flavonoids, vitamin C, antioxidant capacity (DPPH), oxidation index and copper using near infrared (NIR) spectroscopy has been satisfactorily obtained. These models were optimised by cross-validation, and the best model was evaluated according to multiple correlation coefficient (RSQ), standard error of cross-validation (SECV), ratio performance deviation (RPD) and root mean standard error (RMSE) in the prediction set. The result of these statistics suggested that the equations developed could be used for rapid determination of antioxidant compounds in honey. This work shows that near infrared spectroscopy can be considered as rapid tool for the nondestructive measurement of antioxidant constitutes as phenols, flavonoids, vitamin C and copper and also the antioxidant capacity in the honey. Copyright © 2013 Elsevier Ltd. All rights reserved.
Rubio, Joaquín Salmerón; García-Delgado, Pilar; Ferreira, Paula Iglésias; Santos, Henrique Mateus; Martínez-Martínez, Fernando
2014-04-01
The scope of this study was the validation of a cross-culturally adapted questionnaire into Portuguese in five community pharmacies in Portugal. The discriminatory power of items, content and construct validity and factor analysis of the main components and their reliability and stability were determined. A high degree of semantic equivalence between the original questionnaire and the cross-culturally adapted questionnaire into Portuguese was observed. A Kaiser-Meyer-Olkin index of 0.550 was obtained and the Bartlett sphericity test confirmed the adequacy of the data for the application of factor analysis (p <0.0001). Three factors which accounted for 52.6% of the total variability were considered. With respect to reliability the following results were obtained: 0.519 for Cronbach's alpha test; 0.89 for Cohen's kappa coefficient; and 0.756 (IC=0.598-0.963) for the CCI exam. In this work, the first adaptation for the Portuguese culture of a specific questionnaire was produced to measure the degree of knowledge patients have about their medication.
Testing and Validating Machine Learning Classifiers by Metamorphic Testing☆
Xie, Xiaoyuan; Ho, Joshua W. K.; Murphy, Christian; Kaiser, Gail; Xu, Baowen; Chen, Tsong Yueh
2011-01-01
Machine Learning algorithms have provided core functionality to many application domains - such as bioinformatics, computational linguistics, etc. However, it is difficult to detect faults in such applications because often there is no “test oracle” to verify the correctness of the computed outputs. To help address the software quality, in this paper we present a technique for testing the implementations of machine learning classification algorithms which support such applications. Our approach is based on the technique “metamorphic testing”, which has been shown to be effective to alleviate the oracle problem. Also presented include a case study on a real-world machine learning application framework, and a discussion of how programmers implementing machine learning algorithms can avoid the common pitfalls discovered in our study. We also conduct mutation analysis and cross-validation, which reveal that our method has high effectiveness in killing mutants, and that observing expected cross-validation result alone is not sufficiently effective to detect faults in a supervised classification program. The effectiveness of metamorphic testing is further confirmed by the detection of real faults in a popular open-source classification program. PMID:21532969
Longobardi, Francesco; Innamorato, Valentina; Di Gioia, Annalisa; Ventrella, Andrea; Lippolis, Vincenzo; Logrieco, Antonio F; Catucci, Lucia; Agostiano, Angela
2017-12-15
Lentil samples coming from two different countries, i.e. Italy and Canada, were analysed using untargeted 1 H NMR fingerprinting in combination with chemometrics in order to build models able to classify them according to their geographical origin. For such aim, Soft Independent Modelling of Class Analogy (SIMCA), k-Nearest Neighbor (k-NN), Principal Component Analysis followed by Linear Discriminant Analysis (PCA-LDA) and Partial Least Squares-Discriminant Analysis (PLS-DA) were applied to the NMR data and the results were compared. The best combination of average recognition (100%) and cross-validation prediction abilities (96.7%) was obtained for the PCA-LDA. All the statistical models were validated both by using a test set and by carrying out a Monte Carlo Cross Validation: the obtained performances were found to be satisfying for all the models, with prediction abilities higher than 95% demonstrating the suitability of the developed methods. Finally, the metabolites that mostly contributed to the lentil discrimination were indicated. Copyright © 2017 Elsevier Ltd. All rights reserved.
Supersonic, nonlinear, attached-flow wing design for high lift with experimental validation
NASA Technical Reports Server (NTRS)
Pittman, J. L.; Miller, D. S.; Mason, W. H.
1984-01-01
Results of the experimental validation are presented for the three dimensional cambered wing which was designed to achieve attached supercritical cross flow for lifting conditions typical of supersonic maneuver. The design point was a lift coefficient of 0.4 at Mach 1.62 and 12 deg angle of attack. Results from the nonlinear full potential method are presented to show the validity of the design process along with results from linear theory codes. Longitudinal force and moment data and static pressure data were obtained in the Langley Unitary Plan Wind Tunnel at Mach numbers of 1.58, 1.62, 1.66, 1.70, and 2.00 over an angle of attack range of 0 to 14 deg at a Reynolds number of 2.0 x 10 to the 6th power per foot. Oil flow photographs of the upper surface were obtained at M = 1.62 for alpha approx. = 8, 10, 12, and 14 deg.
Psychometric validation of a condom self-efficacy scale in Korean.
Cha, EunSeok; Kim, Kevin H; Burke, Lora E
2008-01-01
When an instrument is translated for use in cross-cultural research, it needs to account for cultural factors without distorting the psychometric properties of the instrument. To validate the psychometric properties of the condom self-efficacy scale (CSE) originally developed for American adolescents and young adults after translating the scale to Korean (CSE-K) to determine its suitability for cross-cultural research among Korean college students. A cross-sectional, correlational design was used with an exploratory survey methodology through self-report questionnaires. A convenience sample of 351 students, aged 18 to 25 years, were recruited at a university in Seoul, Korea. The participants completed the CSE-K and the intention of condom use scales after they were translated from English to Korean using a combined translation technique. A demographic and sex history questionnaire, which included an item to assess actual condom usage, was also administered. Mean, variance, reliability, criterion validity, and factorial validity using confirmatory factor analysis were assessed in the CSE-K. Norms for the CSE-K were similar, but not identical, to norms for the English version. The means of all three subscales were lower for the CSE-K than for the original CSE; however, the obtained variance in CSE-K was roughly similar with the original CSE. The Cronbach's alpha coefficient for the total scale was higher for the CSE-K (.91) than that for either the CSE (.85) or CSE in Thai (.85). Criterion validity and construct validity of the CSE-K were confirmed. The CSE-K was a reliable and valid scale in measuring condom self-efficacy among Korean college students. The findings suggest that the CSE was an appropriate instrument to conduct cross-cultural research on sexual behavior in adolescents and young adults.
Zambelli, Roberto; Pinto, Rafael Z; Magalhães, João Murilo Brandão; Lopes, Fernando Araujo Silva; Castilho, Rodrigo Simões; Baumfeld, Daniel; Dos Santos, Thiago Ribeiro Teles; Maffulli, Nicola
2016-01-01
There is a need for a patient-relevant instrument to evaluate outcome after treatment in patients with a total Achilles tendon rupture. The purpose of this study was to undertake a cross-cultural adaptation of the Achilles Tendon Total Rupture Score (ATRS) into Brazilian Portuguese, determining the test-retest reliability and construct validity of the instrument. A five-step approach was used in the cross-cultural adaptation process: initial translation (two bilingual Brazilian translators), synthesis of translation, back-translation (two native English language translators), consensus version and evaluation (expert committee), and testing phase. A total of 46 patients were recruited to evaluate the test-retest reproducibility and construct validity of the Brazilian Portuguese version of the ATRS. Test-retest reproducibility was performed by assessing each participant on two separate occasions. The construct validity was determined by the correlation index between the ATRS and the Orthopedic American Foot and Ankle Society (AOFAS) questionnaires. The final version of the Brazilian Portuguese ATRS had the same number of questions as the original ATRS. For the reliability analysis, an ICC(2,1) of 0.93 (95 % CI: 0.88 to 0.96) with SEM of 1.56 points and MDC of 4.32 was observed, indicating excellent reliability. The construct validity showed excellent correlation with R = 0.76 (95 % CI: 0.52 to 0.89, P < 0.001). The ATRS was successfully cross-culturally validated into Brazilian Portuguese. This version was a reliable and valid measure of function in patients who suffered complete rupture of the Achilles Tendon.
Lao, Wan-li; He, Yu-chan; Li, Gai-yun; Zhou, Qun
2016-01-01
The biomass to plastic ratio in wood plastic composites (WPCs) greatly affects the physical and mechanical properties and price. Fast and accurate evaluation of the biomass to plastic ratio is important for the further development of WPCs. Quantitative analysis of the WPC main composition currently relies primarily on thermo-analytical methods. However, these methods have some inherent disadvantages, including time-consuming, high analytical errors and sophisticated, which severely limits the applications of these techniques. Therefore, in this study, Fourier Transform Infrared (FTIR) spectroscopy in combination with partial least square (PLS) has been used for rapid prediction of bamboo and polypropylene (PP) content in bamboo/PP composites. The bamboo powders were used as filler after being dried at 105 degrees C for 24 h. PP was used as matrix materials, and some chemical regents were used as additives. Then 42 WPC samples with different ratios of bamboo and PP were prepared by the methods of extrusion. FTIR spectral data of 42 WPC samples were collected by means of KBr pellets technique. The model for bamboo and PP content prediction was developed by PLS-2 and full cross validation. Results of internal cross validation showed that the first derivative spectra in the range of 1 800-800 cm(-1) corrected by standard normal variate (SNV) yielded the optimal model. For both bamboo and PP calibration, the coefficients of determination (R2) were 0.955. The standard errors of calibration (SEC) were 1.872 for bamboo content and 1.848 for PP content, respectively. For both bamboo and PP validation, the R2 values were 0.950. The standard errors of cross validation (SECV) were 1.927 for bamboo content and 1.950 for PP content, respectively. And the ratios of performance to deviation (RPD) were 4.45 for both biomass and PP examinations. The results of external validation showed that the relative prediction deviations for both biomass and PP contents were lower than ± 6%. FTIR combined with PLS can be used for rapid and accurate determination of bamboo and PP content in bamboo/PP composites.
Measuring Cross-Cultural Supernatural Beliefs with Self- and Peer-Reports.
Bluemke, Matthias; Jong, Jonathan; Grevenstein, Dennis; Mikloušić, Igor; Halberstadt, Jamin
2016-01-01
Despite claims about the universality of religious belief, whether religiosity scales have the same meaning when administered inter-subjectively-or translated and applied cross-culturally-is currently unknown. Using the recent "Supernatural Belief Scale" (SBS), we present a primer on how to verify the strong assumptions of measurement invariance required in research on religion. A comparison of two independent samples, Croatians and New Zealanders, showed that, despite a sophisticated psychometric model, measurement invariance could be demonstrated for the SBS except for two noninvariant intercepts. We present a new approach for inspecting measurement invariance across self- and peer-reports as two dependent samples. Although supernatural beliefs may be hard to observe in others, the measurement model was fully invariant for Croatians and their nominated peers. The results not only establish, for the first time, a valid measure of religious supernatural belief across two groups of different language and culture, but also demonstrate a general invariance test for distinguishable dyad members nested within the same targets. More effort needs to be made to design and validate cross-culturally applicable measures of religiosity.
Measuring Cross-Cultural Supernatural Beliefs with Self- and Peer-Reports
Bluemke, Matthias; Jong, Jonathan; Grevenstein, Dennis; Mikloušić, Igor; Halberstadt, Jamin
2016-01-01
Despite claims about the universality of religious belief, whether religiosity scales have the same meaning when administered inter-subjectively–or translated and applied cross-culturally–is currently unknown. Using the recent “Supernatural Belief Scale” (SBS), we present a primer on how to verify the strong assumptions of measurement invariance required in research on religion. A comparison of two independent samples, Croatians and New Zealanders, showed that, despite a sophisticated psychometric model, measurement invariance could be demonstrated for the SBS except for two noninvariant intercepts. We present a new approach for inspecting measurement invariance across self- and peer-reports as two dependent samples. Although supernatural beliefs may be hard to observe in others, the measurement model was fully invariant for Croatians and their nominated peers. The results not only establish, for the first time, a valid measure of religious supernatural belief across two groups of different language and culture, but also demonstrate a general invariance test for distinguishable dyad members nested within the same targets. More effort needs to be made to design and validate cross-culturally applicable measures of religiosity. PMID:27760206
Tilov, Boris; Dimitrova, Donka; Stoykova, Maria; Tornjova, Bianka; Foreva, Gergana; Stoyanov, Drozdstoj
2012-12-01
Health-care professions have long been considered prone to work-related stress, yet recent research in Bulgaria indicates alarmingly high levels of burnout. Cloninger's inventory is used to analyse and evaluate correlation between personality characteristics and degree of burnout syndrome manifestation among the risk categories of health-care professionals. The primary goal of this study was to test the conceptual validity and cross-cultural applicability of the revised TCI (TCI-R), developed in the United States, in a culturally, socially and economically diverse setting. Linguistic validation, test-retest studies, statistical and expert analyses were performed to assess cross-cultural applicability of the revised Cloninger's temperament and character inventory in Bulgarian, its reliability and internal consistency and construct validity. The overall internal consistency of TCI-R and its scales as well as the interscale and test-retest correlations prove that the translated version of the questionnaire is acceptable and cross-culturally applicable for the purposes of studying organizational stress and burnout risk in health-care professionals. In general the cross-cultural adaptation process, even if carried out in a rigorous way, does not always lead to the best target version and suggests it would be useful to develop new scales specific to each culture and, at the same time, to think about the trans-cultural adaptation. © 2012 Blackwell Publishing Ltd.
Cross-cultural adaptation of the Individual Work Performance Questionnaire.
Koopmans, Linda; Bernaards, Claire M; Hildebrandt, Vincent H; Lerner, Debra; de Vet, Henrica C W; van der Beek, Allard J
2015-01-01
The Individual Work Performance Questionnaire (IWPQ), measuring task performance, contextual performance, and counterproductive work behavior, was developed in The Netherlands. To cross-culturally adapt the IWPQ from the Dutch to the American-English language, and assess the questionnaire's internal consistency and content validity in the American-English context. A five stage translation and adaptation process was used: forward translation, synthesis, back-translation, expert committee review, and pilot-testing. During the pilot-testing, cognitive interviews with 40 American workers were performed, to examine the comprehensibility, applicability, and completeness of the American-English IWPQ. Questionnaire instructions were slightly modified to aid interpretation in the American-English language. Inconsistencies with verb tense were identified, and it was decided to consistently use simple past tense. The wording of five items was modified to better suit the American-English language. In general, participants were positive on the comprehensibility, applicability and completeness of the questionnaire during the pilot-testing phase. Furthermore, the study showed positive results concerning the internal consistency (Cronbach's alphas for the scales between 0.79-0.89) and content validity of the American-English IWPQ. The results indicate that the cross-cultural adaptation of the American-English IWPQ was successful and that the measurement properties of the translated version are promising.
Sun, Jiangming; Carlsson, Lars; Ahlberg, Ernst; Norinder, Ulf; Engkvist, Ola; Chen, Hongming
2017-07-24
Conformal prediction has been proposed as a more rigorous way to define prediction confidence compared to other application domain concepts that have earlier been used for QSAR modeling. One main advantage of such a method is that it provides a prediction region potentially with multiple predicted labels, which contrasts to the single valued (regression) or single label (classification) output predictions by standard QSAR modeling algorithms. Standard conformal prediction might not be suitable for imbalanced data sets. Therefore, Mondrian cross-conformal prediction (MCCP) which combines the Mondrian inductive conformal prediction with cross-fold calibration sets has been introduced. In this study, the MCCP method was applied to 18 publicly available data sets that have various imbalance levels varying from 1:10 to 1:1000 (ratio of active/inactive compounds). Our results show that MCCP in general performed well on bioactivity data sets with various imbalance levels. More importantly, the method not only provides confidence of prediction and prediction regions compared to standard machine learning methods but also produces valid predictions for the minority class. In addition, a compound similarity based nonconformity measure was investigated. Our results demonstrate that although it gives valid predictions, its efficiency is much worse than that of model dependent metrics.
Cognitive-Motor Interference in an Ecologically Valid Street Crossing Scenario.
Janouch, Christin; Drescher, Uwe; Wechsler, Konstantin; Haeger, Mathias; Bock, Otmar; Voelcker-Rehage, Claudia
2018-01-01
Laboratory-based research revealed that gait involves higher cognitive processes, leading to performance impairments when executed with a concurrent loading task. Deficits are especially pronounced in older adults. Theoretical approaches like the multiple resource model highlight the role of task similarity and associated attention distribution problems. It has been shown that in cases where these distribution problems are perceived relevant to participant's risk of falls, older adults prioritize gait and posture over the concurrent loading task. Here we investigate whether findings on task similarity and task prioritization can be transferred to an ecologically valid scenario. Sixty-three younger adults (20-30 years of age) and 61 older adults (65-75 years of age) participated in a virtual street crossing simulation. The participants' task was to identify suitable gaps that would allow them to cross a simulated two way street safely. Therefore, participants walked on a manual treadmill that transferred their forward motion to forward displacements in a virtual city. The task was presented as a single task (crossing only) and as a multitask. In the multitask condition participants were asked, among others, to type in three digit numbers that were presented either visually or auditorily. We found that for both age groups, street crossing as well as typing performance suffered under multitasking conditions. Impairments were especially pronounced for older adults (e.g., longer crossing initiation phase, more missed opportunities). However, younger and older adults did not differ in the speed and success rate of crossing. Further, deficits were stronger in the visual compared to the auditory task modality for most parameters. Our findings conform to earlier studies that found an age-related decline in multitasking performance in less realistic scenarios. However, task similarity effects were inconsistent and question the validity of the multiple resource model within ecologically valid scenarios.
Berg, M; Aamodt, G; Stanghelle, J; Krumlinde-Sundholm, L; Hussain, A
2008-09-01
The Pediatric Evaluation of Disability Inventory (PEDI) is one of the most commonly used assessments for children with a disability. Normative data from the US are used to determine whether a deficit or delay exists with regard to functional skill development. The purpose of this study was to analyse the cross-cultural validity of the PEDI American normative data for a general Norwegian population. A random selection of 174 typically developed Norwegian children between 1.0 and 5.9 years participated. The results for capability and caregiver assistance in the domains of self-care, mobility, and social function ranged from a mean of 38.0-46.8 against an expected 50. The Norwegian sample scored significantly lower than the US reference values for functional skills and caregiver assistance, and the results had less fit, especially for self-care. For mobility and social function, the magnitudes of the differences were smaller than self-care. Specific items deviated, suggesting necessary adjustments for the applicability of the norm-referenced scores of the PEDI in the Norwegian culture. The result of this research confirms other findings of cultural influence of the age norms in PEDI. Even though interpretations of the normative score results must be made with some caution, the option of using the scaled scores of PEDI is useful and recommended to describe and measure abilities and to evaluate change. This finding highlights the importance of cultural validation of norm-referenced tests.
Beckerman, Bernardo S; Jerrett, Michael; Serre, Marc; Martin, Randall V; Lee, Seung-Jae; van Donkelaar, Aaron; Ross, Zev; Su, Jason; Burnett, Richard T
2013-07-02
Airborne fine particulate matter exhibits spatiotemporal variability at multiple scales, which presents challenges to estimating exposures for health effects assessment. Here we created a model to predict ambient particulate matter less than 2.5 μm in aerodynamic diameter (PM2.5) across the contiguous United States to be applied to health effects modeling. We developed a hybrid approach combining a land use regression model (LUR) selected with a machine learning method, and Bayesian Maximum Entropy (BME) interpolation of the LUR space-time residuals. The PM2.5 data set included 104,172 monthly observations at 1464 monitoring locations with approximately 10% of locations reserved for cross-validation. LUR models were based on remote sensing estimates of PM2.5, land use and traffic indicators. Normalized cross-validated R(2) values for LUR were 0.63 and 0.11 with and without remote sensing, respectively, suggesting remote sensing is a strong predictor of ground-level concentrations. In the models including the BME interpolation of the residuals, cross-validated R(2) were 0.79 for both configurations; the model without remotely sensed data described more fine-scale variation than the model including remote sensing. Our results suggest that our modeling framework can predict ground-level concentrations of PM2.5 at multiple scales over the contiguous U.S.
How bandwidth selection algorithms impact exploratory data analysis using kernel density estimation.
Harpole, Jared K; Woods, Carol M; Rodebaugh, Thomas L; Levinson, Cheri A; Lenze, Eric J
2014-09-01
Exploratory data analysis (EDA) can reveal important features of underlying distributions, and these features often have an impact on inferences and conclusions drawn from data. Graphical analysis is central to EDA, and graphical representations of distributions often benefit from smoothing. A viable method of estimating and graphing the underlying density in EDA is kernel density estimation (KDE). This article provides an introduction to KDE and examines alternative methods for specifying the smoothing bandwidth in terms of their ability to recover the true density. We also illustrate the comparison and use of KDE methods with 2 empirical examples. Simulations were carried out in which we compared 8 bandwidth selection methods (Sheather-Jones plug-in [SJDP], normal rule of thumb, Silverman's rule of thumb, least squares cross-validation, biased cross-validation, and 3 adaptive kernel estimators) using 5 true density shapes (standard normal, positively skewed, bimodal, skewed bimodal, and standard lognormal) and 9 sample sizes (15, 25, 50, 75, 100, 250, 500, 1,000, 2,000). Results indicate that, overall, SJDP outperformed all methods. However, for smaller sample sizes (25 to 100) either biased cross-validation or Silverman's rule of thumb was recommended, and for larger sample sizes the adaptive kernel estimator with SJDP was recommended. Information is provided about implementing the recommendations in the R computing language. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Zhang, Shuang; Xue, Xiwen; Zhang, Liangren; Zhang, Lihe; Liu, Zhenming
2015-12-01
In the past decade, the discovery, synthesis, and evaluation for hundreds of CD38 covalent and non-covalent inhibitors has been reported sequentially by our group and partners; however, a systematic structure-based guidance is still lacking for rational design of CD38 inhibitor. Here, we carried out a comparative analysis of pharmacophore features and quantitative structure-activity relationships for CD38 inhibitors. The results uncover that the essential interactions between key residues and covalent/non-covalent CD38 inhibitors include (i) hydrogen bond and hydrophobic interactions with residues Glu226 and Trp125, (ii) electrostatic or hydrogen bond interaction with the positively charged residue Arg127 region, and (iii) the hydrophobic interaction with residue Trp189. For covalent inhibitors, besides the covalent effect with residue Glu226, the electrostatic interaction with residue Arg127 is also necessary, while another hydrogen/non-bonded interaction with residues Trp125 and Trp189 can also be detected. By means of the SYBYL multifit alignment function, the best CoMFA and CoMSIA with CD38 covalent inhibitors presented cross-validated correlation coefficient values (q(2)) of 0.564 and 0.571, and non-cross-validated values (r(2)) of 0.967 and 0.971, respectively. The CD38 non-covalent inhibitors can be classified into five groups according to their chemical scaffolds, and the residues Glu226, Trp189, and Trp125 are indispensable for those non-covalent inhibitors binding to CD38, while the residues Ser126, Arg127, Asp155, Thr221, and Phe222 are also important. The best CoMFA and CoMSIA with the F12 analogues presented cross-validated correlation coefficient values (q(2)) of 0.469 and 0.454, and non-cross-validated values (r(2)) of 0.814 and 0.819, respectively. © 2015 John Wiley & Sons A/S.
Simonelli, A; Sacchi, C; Cantoni, L; Brown, M; Frewen, P
2017-01-01
Background : The Childhood Attachment and Relational Trauma Screen (CARTS) is a computer-administered survey designed to assess retrospectively the socio-ecological context in which instances of child abuse may have occurred. To date, studies supporting the validity of the CARTS have only been undertaken in English-speaking North American populations. Validation projects in other countries and cross-cultural comparisons are therefore warranted. Objective : Develop and preliminarily evaluate the psychometric properties of an Italian version of the CARTS on college students and compare such observations to data acquired from Canadian students. Method : Seventy-nine undergraduate students from the University of Padua (Italy) completed an Italian translation of the CARTS as well as measures of childhood experiences, mental health and attachment, responses to which were compared to those obtained in 288 Canadian students who completed the CARTS in English. Results : Internal consistency and convergent validity with the Childhood Trauma Questionnaire and Parental Bonding Instrument were found to be acceptable for the Italian translation. Within the Italian sample, correlation analyses suggested that CARTS Mother ratings referring to attachment and abuse were associated with romantic attachment, whereas CARTS Father ratings were significantly correlated to PTSD symptoms and other symptoms of psychopathology-distress. Significant differences between Italian and Canadian students across the relationship types for the CARTS abuse and attachment scales were found, indicating that Italian students rated their mothers and fathers as simultaneously less abusive, but also less as a source of secure attachment. Conclusions : The results of this preliminary study seem to suggest convergent validity of the Italian CARTS and the association between childhood attachment-related experiences and romantic attachment. Cultural variations were identified between Canadian and Italian students in both attachment and abuse scales. Future studies to investigate cross-cultural variations in the relational context of childhood abuse and in order to boost Italian CARTS psychometric features are warranted.
Simonelli, A.; Sacchi, C.; Cantoni, L.; Brown, M.; Frewen, P.
2017-01-01
ABSTRACT Background: The Childhood Attachment and Relational Trauma Screen (CARTS) is a computer-administered survey designed to assess retrospectively the socio-ecological context in which instances of child abuse may have occurred. To date, studies supporting the validity of the CARTS have only been undertaken in English-speaking North American populations. Validation projects in other countries and cross-cultural comparisons are therefore warranted. Objective: Develop and preliminarily evaluate the psychometric properties of an Italian version of the CARTS on college students and compare such observations to data acquired from Canadian students. Method: Seventy-nine undergraduate students from the University of Padua (Italy) completed an Italian translation of the CARTS as well as measures of childhood experiences, mental health and attachment, responses to which were compared to those obtained in 288 Canadian students who completed the CARTS in English. Results: Internal consistency and convergent validity with the Childhood Trauma Questionnaire and Parental Bonding Instrument were found to be acceptable for the Italian translation. Within the Italian sample, correlation analyses suggested that CARTS Mother ratings referring to attachment and abuse were associated with romantic attachment, whereas CARTS Father ratings were significantly correlated to PTSD symptoms and other symptoms of psychopathology-distress. Significant differences between Italian and Canadian students across the relationship types for the CARTS abuse and attachment scales were found, indicating that Italian students rated their mothers and fathers as simultaneously less abusive, but also less as a source of secure attachment. Conclusions: The results of this preliminary study seem to suggest convergent validity of the Italian CARTS and the association between childhood attachment-related experiences and romantic attachment. Cultural variations were identified between Canadian and Italian students in both attachment and abuse scales. Future studies to investigate cross-cultural variations in the relational context of childhood abuse and in order to boost Italian CARTS psychometric features are warranted. PMID:29163857
SMAP RADAR Calibration and Validation
NASA Astrophysics Data System (ADS)
West, R. D.; Jaruwatanadilok, S.; Chaubel, M. J.; Spencer, M.; Chan, S. F.; Chen, C. W.; Fore, A.
2015-12-01
The Soil Moisture Active Passive (SMAP) mission launched on Jan 31, 2015. The mission employs L-band radar and radiometer measurements to estimate soil moisture with 4% volumetric accuracy at a resolution of 10 km, and freeze-thaw state at a resolution of 1-3 km. Immediately following launch, there was a three month instrument checkout period, followed by six months of level 1 (L1) calibration and validation. In this presentation, we will discuss the calibration and validation activities and results for the L1 radar data. Early SMAP radar data were used to check commanded timing parameters, and to work out issues in the low- and high-resolution radar processors. From April 3-13 the radar collected receive only mode data to conduct a survey of RFI sources. Analysis of the RFI environment led to a preferred operating frequency. The RFI survey data were also used to validate noise subtraction and scaling operations in the radar processors. Normal radar operations resumed on April 13. All radar data were examined closely for image quality and calibration issues which led to improvements in the radar data products for the beta release at the end of July. Radar data were used to determine and correct for small biases in the reported spacecraft attitude. Geo-location was validated against coastline positions and the known positions of corner reflectors. Residual errors at the time of the beta release are about 350 m. Intra-swath biases in the high-resolution backscatter images are reduced to less than 0.3 dB for all polarizations. Radiometric cross-calibration with Aquarius was performed using areas of the Amazon rain forest. Cross-calibration was also examined using ocean data from the low-resolution processor and comparing with the Aquarius wind model function. Using all a-priori calibration constants provided good results with co-polarized measurements matching to better than 1 dB, and cross-polarized measurements matching to about 1 dB in the beta release. During the second half of the L1 cal/val period, the RFI removal algorithm will be tuned for optimal performance, and the Faraday rotation corrections used in radar processing will be further developed and validated. This work is supported by the SMAP project at the Jet Propulsion Laboratory, California Institute of Technology.
Development and validation of the Work Conflict Appraisal Scale (WCAS).
González-Navarro, Pilar; Llinares-Insa, Lucía; Zurriaga-Llorens, Rosario; Lloret-Segura, Susana
2017-05-01
In the context of cognitive appraisal, the Work Conflict Appraisal Scale (WCAS) was developed to assess work conflict in terms of threat and challenge. In the first study, the factorial structure of the scale was tested using confirmatory factor analysis with a Spanish multi-occupational employee sample (N= 296). In the sec-ond study, we used multi-sampling confirmatory factor analysis (N= 815) to cross-validate the results. The analyses confirm the validity of the scale and are con-sistent with the tri-dimensional conflict classification. The findings support the distinc-tion between the challenge and threat appraisals of work conflict, highlighting the im-portance of measuring these two types of appraisal separately. This scale is a valid and reliable instrument to measure conflict appraisal in organizations.
Huang, Hui-Chuan; Shyu, Meei-Ling; Lin, Mei-Feng; Hu, Chaur-Jong; Chang, Chien-Hung; Lee, Hsin-Chien; Chi, Nai-Fang; Chang, Hsiu-Ju
2017-12-01
The objectives of this study were to develop a cross-cultural Chinese version of the Emotional and Social Dysfunction Questionnaire (ESDQ-C) and test its validity and reliability among Chinese-speaking stroke patients. Various methods were used to develop the ESDQ-C. A cross-sectional study was used to examine the validity and reliability of the developed questionnaire, which consists of 28 items belonging to six factors, anger, helplessness, emotional dyscontrol, indifference, inertia and fatigue, and euphoria. Satisfactory convergence and known-group validities were confirmed by significant correlations of the ESDQ-C with the Profile of Mood States-Short Form ( p < .05) and with the Hospital Anxiety and Depression Scale ( p < .05). The internal consistency was represented by Cronbach's alpha, which was .96 and .79 to .92 for the entire scale and subscales, respectively. Appropriate application of the ESDQ-C will be helpful to identify critical adjustment-related types of distress and patients who experience difficulty coping with such distress.
Rosen, Allyson; Weitlauf, Julie C
2015-01-01
A screening measure of capacity to consent can provide an efficient method of determining the appropriateness of including individuals from vulnerable patient populations in research, particularly in circumstances in which no caregiver is available to provide surrogate consent. Seaman et al. (2015) cross-validate a measure of capacity to consent to research developed by Jeste et al. (2007). They provide data on controls, caregivers, and patients with mild cognitive impairment and dementia. The study demonstrates the importance of validating measures across disorders with different domains of incapacity, as well as the need for timely and appropriate follow-up with potential participants who yield positive screens. Ultimately clinical measures need to adapt to the dimensional diagnostic approaches put forward in DSM 5. Integrative models of constructs, such as capacity to consent, will make this process more efficient by avoiding the need to test measures in each disorder. Until then, cross-validation studies, such as the work by Seaman et al. (2015) are critical.
Multivariate Models of Men's and Women's Partner Aggression
ERIC Educational Resources Information Center
O'Leary, K. Daniel; Smith Slep, Amy M.; O'Leary, Susan G.
2007-01-01
This exploratory study was designed to address how multiple factors drawn from varying focal models and ecological levels of influence might operate relative to each other to predict partner aggression, using data from 453 representatively sampled couples. The resulting cross-validated models predicted approximately 50% of the variance in men's…
Pettiness: Conceptualization, measurement and cross-cultural differences.
Ng, Reuben; Levy, Becca
2018-01-01
Although pettiness, defined as the tendency to get agitated over trivial matters, is a facet of neuroticism which has negative health implications, no measure exists. The goal of the current study was to develop, and validate a short pettiness scale. In Study 1 (N = 2136), Exploratory Factor Analysis distilled a one-factor model with five items. Convergent validity was established using the Big Five Inventory, DASS, Satisfaction with Life Scale, and Conner-Davidson Resilience Scale. As predicted, pettiness was positively associated with neuroticism, depression, anxiety and stress but negatively related to extraversion, agreeableness, conscientiousness, openness, life satisfaction and resilience. Also, as predicted, pettiness was not significantly related to physical functioning, or blind and constructive patriotism, indicating discriminant validity. Confirmatory Factor Analysis in Study 2 (N = 734) revealed a stable one-factor model of pettiness. In Study 3 (N = 532), the scale, which showed a similar factor structure in the USA and Singapore, also reflected predicted cross-cultural patterns: Pettiness was found to be significantly lower in the United States, a culture categorized as "looser" than in Singapore, a culture classified as "tighter" in terms of Gelfand and colleagues' framework of national tendencies to oppose social deviance. Results suggest that this brief 5-item tool is a reliable and valid measure of pettiness, and its use in health research is encouraged.
Shafeei, Asrin; Mokhtarinia, Hamid Reza; Maleki-Ghahfarokhi, Azam; Piri, Leila
2017-08-01
Observational study. To cross-culturally translate the Orebro Musculoskeletal Pain Screening Questionnaire (OMPQ) into Persian and then evaluate its psychometric properties (reliability, validity, ceiling, and flooring effects). To the authors' knowledge, prior to this study there has been no validated instrument to screen the risk of chronicity in Persian-speaking patients with low back pain (LBP) in Iran. The OMPQ was specifically developed as a self-administered screening tool for assessing the risk of LBP chronicity. The forward-backward translation method was used for the translation and cross-cultural adaptation of the original questionnaire. In total, 202 patients with subacute LBP completed the OMPQ and the pain disability questionnaire (PDQ), which was used to assess convergent validity. 62 patients completed the OMPQ a week later as a retest. Slight changes were made to the OMPQ during the translation/cultural adaptation process; face validity of the Persian version was obtained. The Persian OMPQ showed excellent test-retest reliability (intraclass correlation coefficient=0.89). Its internal consistency was 0.71, and its convergent validity was confirmed by good correlation coefficient between the OMPQ and PDQ total scores ( r =0.72, p <0.05). No ceiling or floor effects were observed. The Persian version of the OMPQ is acceptable for the target society in terms of face validity, construct validity, reliability, and consistency. It is therefore considered a useful instrument for screening Iranian patients with LBP.
Validity of the FACT-H&N (v 4.0) among Malaysian oral cancer patients.
Doss, J G; Thomson, W M; Drummond, B K; Raja Latifah, R J
2011-07-01
To assess the cross-sectional construct validity of the Malay-translated and cross-culturally adapted FACT-H&N (v 4.0) for discriminative use in a sample of Malaysian oral cancer patients. A cross-sectional study of adults newly diagnosed with oral cancer. HRQOL data were collected using the FACT-H&N (v 4.0), a global question and a supplementary set of eight questions ('MAQ') obtained earlier in pilot work. Of the 76 participants (61.8% female; 23.7% younger than 50), most (96.1%) had oral squamous cell carcinoma; two-thirds were in Stages III or IV. At baseline, patients' mean FACT summary (FACT-G, FACT-H&N, FACT-H&N TOI, and FHNSI) and subscale (pwb, swb, ewb, fwb, and hnsc) scores were towards the higher end of the range. Equal proportions (36.8%) rated their overall HRQOL as 'good' or 'average'; fewer than one-quarter rated it as 'poor', and only two as 'very good'. All six FACT summary and most subscales had moderate-to-good internal consistency. For all summary scales, those with 'very poor/poor' self-rated HRQOL differed significantly from the 'good/very good' group. All FACT summary scales correlated strongly (r>0.75). Summary scales showed convergent validity (r>0.90) but little discriminant validity. The discriminant validity of the FHNSI improved with the addition of the MAQ. The FACT-H&N summary scales and most subscales demonstrated acceptable cross-sectional construct validity, reliability and discriminative ability, and thus appear appropriate for further use among Malaysian oral cancer patients. Copyright © 2011 Elsevier Ltd. All rights reserved.
Initial Reliability and Validity of the Perceived Social Competence Scale
ERIC Educational Resources Information Center
Anderson-Butcher, Dawn; Iachini, Aidyn L.; Amorose, Anthony J.
2008-01-01
Objective: This study describes the development and validation of a perceived social competence scale that social workers can easily use to assess children's and youth's social competence. Method: Exploratory and confirmatory factor analyses were conducted on a calibration and a cross-validation sample of youth. Predictive validity was also…
Beaulieu, J; Doerksen, T; Clément, S; MacKay, J; Bousquet, J
2014-01-01
Genomic selection (GS) is of interest in breeding because of its potential for predicting the genetic value of individuals and increasing genetic gains per unit of time. To date, very few studies have reported empirical results of GS potential in the context of large population sizes and long breeding cycles such as for boreal trees. In this study, we assessed the effectiveness of marker-aided selection in an undomesticated white spruce (Picea glauca (Moench) Voss) population of large effective size using a GS approach. A discovery population of 1694 trees representative of 214 open-pollinated families from 43 natural populations was phenotyped for 12 wood and growth traits and genotyped for 6385 single-nucleotide polymorphisms (SNPs) mined in 2660 gene sequences. GS models were built to predict estimated breeding values using all the available SNPs or SNP subsets of the largest absolute effects, and they were validated using various cross-validation schemes. The accuracy of genomic estimated breeding values (GEBVs) varied from 0.327 to 0.435 when the training and the validation data sets shared half-sibs that were on average 90% of the accuracies achieved through traditionally estimated breeding values. The trend was also the same for validation across sites. As expected, the accuracy of GEBVs obtained after cross-validation with individuals of unknown relatedness was lower with about half of the accuracy achieved when half-sibs were present. We showed that with the marker densities used in the current study, predictions with low to moderate accuracy could be obtained within a large undomesticated population of related individuals, potentially resulting in larger gains per unit of time with GS than with the traditional approach. PMID:24781808
Saub, R; Locker, D; Allison, P; Disman, M
2007-09-01
The aim of this project was to develop an oral health related-quality of life measure for the Malaysian adult population aged 18 and above by the cross-cultural adaption the Oral Health Impact Profile (OHIP). The adaptation of the OHIP was based on the framework proposed by Herdman et al (1998). The OHIP was translated into the Malay language using a forward-backward translation technique. Thirty-six patients were interviewed to assess the conceptual equivalence and relevancy of each item. Based on the translation process and interview results a Malaysian version of the OHIP questionnaire was produced that contained 45 items. It was designated as the OHIP(M). This questionnaire was pre-tested on 20 patients to assess its face validity. A short 14-item version of the questionnaire was completed by 171 patients to assess the suitability of the Likert-type response format. Field-testing was conducted in order to assess the suitability of two modes of administration (mail and interview) and to establish the psychometric properties of the adapted measure. The pre-testing revealed that the OHIP(M) has good face validity. It was found that the five-point frequency Likert scale could be used for the Malaysian population. The OHIP(M) was reliable, where the scale Cronbach's alpha was 0.95 and the ICC value for test-retest reliability was 0.79. Three out four construct validity hypotheses tested were confirmed. OHIP(M) works equally well as the English version. OHIP(M) was found to be reliable and valid regardless of the mode of administration. However, this study only provides initial evidence for the reliability and validity of the measure. Further study is recommended to collect more evidence to support these results.
Aghayev, Emin; Staub, Lukas; Dirnhofer, Richard; Ambrose, Tony; Jackowski, Christian; Yen, Kathrin; Bolliger, Stephan; Christe, Andreas; Roeder, Christoph; Aebi, Max; Thali, Michael J
2008-04-01
Recent developments in clinical radiology have resulted in additional developments in the field of forensic radiology. After implementation of cross-sectional radiology and optical surface documentation in forensic medicine, difficulties in the validation and analysis of the acquired data was experienced. To address this problem and for the comparison of autopsy and radiological data a centralized database with internet technology for forensic cases was created. The main goals of the database are (1) creation of a digital and standardized documentation tool for forensic-radiological and pathological findings; (2) establishing a basis for validation of forensic cross-sectional radiology as a non-invasive examination method in forensic medicine that means comparing and evaluating the radiological and autopsy data and analyzing the accuracy of such data; and (3) providing a conduit for continuing research and education in forensic medicine. Considering the infrequent availability of CT or MRI for forensic institutions and the heterogeneous nature of case material in forensic medicine an evaluation of benefits and limitations of cross-sectional imaging concerning certain forensic features by a single institution may be of limited value. A centralized database permitting international forensic and cross disciplinary collaborations may provide important support for forensic-radiological casework and research.
Measurement of stream channel habitat using sonar
Flug, Marshall; Seitz, Heather; Scott, John
1998-01-01
An efficient and low cost technique using a sonar system was evaluated for describing channel geometry and quantifying inundated area in a large river. The boat-mounted portable sonar equipment was used to record water depths and river width measurements for direct storage on a laptop computer. The field data collected from repeated traverses at a cross-section were evaluated to determine the precision of the system and field technique. Results from validation at two different sites showed average sample standard deviations (S.D.s) of 0.12 m for these complete cross-sections, with coefficient of variations of 10%. Validation using only the mid-channel river cross-section data yields an average sample S.D. of 0.05 m, with a coefficient of variation below 5%, at a stable and gauged river site using only measurements of water depths greater than 0.6 m. Accuracy of the sonar system was evaluated by comparison to traditionally surveyed transect data from a regularly gauged site. We observed an average mean squared deviation of 46.0 cm2, considering only that portion of the cross-section inundated by more than 0.6 m of water. Our procedure proved to be a reliable, accurate, safe, quick, and economic method to record river depths, discharges, bed conditions, and substratum composition necessary for stream habitat studies.
Development and validation of the Relaxation-Mindfulness Scale for Adolescents (EREMIND-A).
López-González, Luis; Amutio, Alberto; Oriol, Xavier; Gázquez, José J; Pérez-Fuentes, Mª C; Molero, Mª M
2018-05-01
The aim of this investigation was to validate the Relaxation-Mindfulness Scale for Adolescents (EREMIND-A), consisting of 18 items and three factors (Attention-Concentration in the present moment; Relaxation (abilities and attitudes); and Sensory awareness/Contemplation/Interiority). The validation was done with a sample of Secondary Education and Baccalaureate students from four different centres in Spain (n = 1.120). EFA and CFA of the EREMIND-A were performed and construct and incremental validities calculated. Initial results confirm the validity and reliability of the scale. There is a need for a broader conceptualization of mindfulness, as well as the inclusion and analysis of other related and cross-cutting concepts. The research in this sense will propitiate the adaptation of the Mindfulness-Based Interventions to the reality of the adolescents in the educational centers, where relaxation and the interiority are aspects to be taken into consideration.
Development and Validation of the Elder Learning Barriers Scale Among Older Chinese Adults.
Wang, Renfeng; De Donder, Liesbeth; De Backer, Free; He, Tao; Van Regenmortel, Sofie; Li, Shihua; Lombaerts, Koen
2017-12-01
This study describes the development and validation of the Elder Learning Barriers (ELB) scale, which seeks to identify the obstacles that affect the level of educational participation of older adults. The process of item pool design and scale development is presented, as well as the testing and scale refinement procedure. The data were collected from a sample of 579 older Chinese adults (aged over 55) in the Xi'an region of China. After randomly splitting the sample for cross-validation purposes, the construct validity of the ELB scale was confirmed containing five dimensions: dispositional, informational, physical, situational, and institutional barriers. Furthermore, developmental differences in factor structure have been examined among older age groups. The results indicated that the scale demonstrated good reliability and validity. We conclude in general that the ELB scale appears to be a valuable instrument for examining the learning barriers that older Chinese citizens experience for participating in organized educational activities.
Psychological collectivism: a measurement validation and linkage to group member performance.
Jackson, Christine L; Colquitt, Jason A; Wesson, Michael J; Zapata-Phelan, Cindy P
2006-07-01
The 3 studies presented here introduce a new measure of the individual-difference form of collectivism. Psychological collectivism is conceptualized as a multidimensional construct with the following 5 facets: preference for in-groups, reliance on in-groups, concern for in-groups, acceptance of in-group norms, and prioritization of in-group goals. Study 1 developed and tested the new measure in a sample of consultants. Study 2 cross-validated the measure using an alumni sample of a Southeastern university, assessing its convergent validity with other collectivism measures. Study 3 linked scores on the measure to 4 dimensions of group member performance (task performance, citizenship behavior, counterproductive behavior, and withdrawal behavior) in a computer software firm and assessed discriminant validity using the Big Five. The results of the studies support the construct validity of the measure and illustrate the potential value of collectivism as a predictor of group member performance. ((c) 2006 APA, all rights reserved).
ERIC Educational Resources Information Center
Morris, Cody E.; Owens, Scott G.; Waddell, Dwight E.; Bass, Martha A.; Bentley, John P.; Loftin, Mark
2014-01-01
An equation published by Loftin, Waddell, Robinson, and Owens (2010) was cross-validated using ten normal-weight walkers, ten overweight walkers, and ten distance runners. Energy expenditure was measured at preferred walking (normal-weight walker and overweight walkers) or running pace (distance runners) for 5 min and corrected to a mile. Energy…
ERIC Educational Resources Information Center
Pecorella, Patricia A.; Bowers, David G.
Multiple regression in a double cross-validated design was used to predict two performance measures (total variable expense and absence rate) by multi-month period in five industrial firms. The regressions do cross-validate, and produce multiple coefficients which display both concurrent and predictive effects, peaking 18 months to two years…
ERIC Educational Resources Information Center
van den Broek, Anneke; Golden, Charles J.; Loonstra, Ann; Ghinglia, Katheryne; Goldstein, Diane
1998-01-01
Indicated excellent cross-validations with correlation of 0.99 for past formulas (J. L. Woodard and B. N. Axelrod, 1995; B. N. Axelrod et al, 1996) for estimating the Wechsler Memory Scale- Revised General Memory and Delayed Recall Indexes. Over 85% of the estimated scores were within 10 points of actual scores. Age, education, diagnosis, and IQ…
ERIC Educational Resources Information Center
Teo, Timothy
2010-01-01
Purpose: The purpose of this paper is to assess the cross-cultural validity of the technology acceptance measure for pre-service teachers (TAMPST) on a Malaysian sample. Design/methodology/approach: A total of 193 pre-service teachers from a Malaysian university completed a survey questionnaire measuring their responses to five constructs in the…
He, S L; Wang, J H; Ji, P
2018-03-01
To validate the Pain Resilience Scale (PRS) for use in Chinese patients with temporomandibular disorders (TMD) pain. According to international guidelines, the original PRS was first translated and cross-culturally adapted to formulate the Chinese version of PRS (PRS-C). A total of 152 patients with TMD pain were recruited to complete series of questionnaires. Reliability of the PRS-C was investigated using internal consistency and test-retest reliability. Validity of the PRS-C was calculated using cross-cultural validity and convergent validity. Cross-cultural validity was evaluated by examining the confirmatory factor analysis (CFA). And convergent validity was examined through correlating the PRS-C scores with scores of 2 commonly used pain-related measures (the Connor-Davidson Resilience Scale [CD-RISC] and the Tampa Scale for Kinesiophobia for Temporomandibular Disorders [TSK-TMD]). The PRS-C had a high internal consistency (Cronbach's alpha = 0.92) and good test-retest reliability (intra-class correlation coefficient [ICC] = 0.81). The CFA supported a 2-factor model for the PRS-C with acceptable fit to the data. The fit indices were chi-square/DF = 2.21, GFI = 0.91, TLI = 0.97, CFI = 0.98 and RMSEA = 0.08. As regards convergent validity, the PRS-C evidenced moderate-to-good relationships with the CD-RISC and the TSK-TMD. The PRS-C shows good psychometric properties and could be considered as a reliable and valid measure to evaluate pain-related resilience in patients with TMD pain. © 2017 John Wiley & Sons Ltd.
Measuring Nigrescence Attitudes in School-Aged Adolescents
ERIC Educational Resources Information Center
Gardner-Kitt, Donna L.; Worrell, Frank C.
2007-01-01
In this study, we examined the reliability and validity of Cross Racial Identity Scale (CRIS; Vandiver, B. J., Cross Jr., W. E., Fhagen-Smith, P. E., Worrell, F. C., Swim, J. K., & Caldwell, L. D. (2000). "The Cross Racial Identity Scale." Unpublished scale; Worrell, F. C., Vandiver, B. J., & Cross Jr., W. E., (2004). "The Cross Racial Identity…
Evaluated cross-section libraries and kerma factors for neutrons up to 100 MeV on {sup 12}C
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chadwick, M.B.; Blann, M.; Cox, L.
1995-04-11
A program is being carried out at Lawrence Livermore National Laboratory to develop high-energy evaluated nuclear data libraries for use in Monte Carlo simulations of cancer radiation therapy. In this report we describe evaluated cross sections and kerma factors for neutrons with incident energies up to 100 MeV on {sup 12}C. The aim of this effort is to incorporate advanced nuclear physics modeling methods, with new experimental measurements, to generate cross section libraries needed for an accurate simulation of dose deposition in fast neutron therapy. The evaluated libraries are based mainly on nuclear model calculations, benchmarked to experimental measurements wheremore » they exist. We use the GNASH code system, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms. The libraries tabulate elastic and nonelastic cross sections, angle-energy correlated production spectra for light ejectiles with A{le}and kinetic energies given to light ejectiles and heavy recoil fragments. The major steps involved in this effort are: (1) development and validation of nuclear models for incident energies up to 100 MeV; (2) collation of experimental measurements, including new results from Louvain-la-Nueve and Los Alamos; (3) extension of the Livermore ENDL formats for representing high-energy data; (4) calculation and evaluation of nuclear data; and (5) validation of the libraries. We describe the evaluations in detail, with particular emphasis on our new high-energy modeling developments. Our evaluations agree well with experimental measurements of integrated and differential cross sections. We compare our results with the recent ENDF/B-VI evaluation which extends up to 32 MeV.« less
Kusano, Kristofer; Gabler, Hampton C
2014-01-01
The odds of death for a seriously injured crash victim are drastically reduced if he or she received care at a trauma center. Advanced automated crash notification (AACN) algorithms are postcrash safety systems that use data measured by the vehicles during the crash to predict the likelihood of occupants being seriously injured. The accuracy of these models are crucial to the success of an AACN. The objective of this study was to compare the predictive performance of competing injury risk models and algorithms: logistic regression, random forest, AdaBoost, naïve Bayes, support vector machine, and classification k-nearest neighbors. This study compared machine learning algorithms to the widely adopted logistic regression modeling approach. Machine learning algorithms have not been commonly studied in the motor vehicle injury literature. Machine learning algorithms may have higher predictive power than logistic regression, despite the drawback of lacking the ability to perform statistical inference. To evaluate the performance of these algorithms, data on 16,398 vehicles involved in non-rollover collisions were extracted from the NASS-CDS. Vehicles with any occupants having an Injury Severity Score (ISS) of 15 or greater were defined as those requiring victims to be treated at a trauma center. The performance of each model was evaluated using cross-validation. Cross-validation assesses how a model will perform in the future given new data not used for model training. The crash ΔV (change in velocity during the crash), damage side (struck side of the vehicle), seat belt use, vehicle body type, number of events, occupant age, and occupant sex were used as predictors in each model. Logistic regression slightly outperformed the machine learning algorithms based on sensitivity and specificity of the models. Previous studies on AACN risk curves used the same data to train and test the power of the models and as a result had higher sensitivity compared to the cross-validated results from this study. Future studies should account for future data; for example, by using cross-validation or risk presenting optimistic predictions of field performance. Past algorithms have been criticized for relying on age and sex, being difficult to measure by vehicle sensors, and inaccuracies in classifying damage side. The models with accurate damage side and including age/sex did outperform models with less accurate damage side and without age/sex, but the differences were small, suggesting that the success of AACN is not reliant on these predictors.
Kaux, Jean-François; Delvaux, François; Schaus, Jean; Demoulin, Christophe; Locquet, Médéa; Buckinx, Fanny; Beaudart, Charlotte; Dardenne, Nadia; Van Beveren, Julien; Croisier, Jean-Louis; Forthomme, Bénédicte; Bruyère, Olivier
Translation and validation of algo-functional questionnaire. The lateral elbow tendinopathy is a common injury in tennis players and physical workers. The Patient-Rated Tennis Elbow Evaluation (PRTEE) Questionnaire was specifically designed to measure pain and functional limitations in patients with lateral epicondylitis (tennis elbow). First developed in English, this questionnaire has since been translated into several languages. The aims of the study were to translate and cross-culturally adapt the PRTEE questionnaire into French and to evaluate the reliability and validity of this translated version of the questionnaire (PRTEE-F). The PRTEE was translated and cross-culturally adapted into French according to international guidelines. To assess the reliability and validity of the PRTEE-F, 115 participants were asked twice to fill in the PRTEE-F, and once the Disabilities of Arm, Shoulder and Hand Questionnaire (DASH) and the Short Form Health Survey (SF-36). Internal consistency (using Cronbach's alpha), test-retest reliability (using intraclass correlation coefficient (ICC), standard error of measurement and minimal detectable change), and convergent and divergent validity (using the Spearman's correlation coefficients respectively with the DASH and with some subscales of the SF-36) were assessed. The PRTEE was translated into French without any problems. PRTEE-F showed a good test-retest reliability for the overall score (ICC 0.86) and for each item (ICC 0.8-0.96) and a high internal consistency (Cronbach's alpha = 0.98). The correlation analyses revealed high correlation coefficients between PRTEE-F and DASH (convergent validity) and, as expected, a low or moderate correlation with the divergent subscales of the SF-36 (discriminant validity). There was no floor or ceiling effect. The PRTEE questionnaire was successfully cross-culturally adapted into French. The PRTEE-F is reliable and valid for evaluating French-speaking patients with lateral elbow tendinopathy. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.
Machado, Inês Maria de Jesus; Bandeira, Marina Bittencourt; Pinheiro, Hélady Sanders; Dutra, Nathália Dos Santos
2015-10-01
Treatment adherence in hemodialysis is important for guaranteeing better results for patients, but Brazil still lacks validated assessment tools for this purpose. The current study aimed to perform a cross-cultural adaptation of the Renal Adherence Behaviour Questionnaire (RABQ) and the Renal Adherence Attitudes Questionnaire (RAAQ). The two questionnaires were submitted to the following cross-cultural adaptation procedures: translation, back-translation, expert panel review, and pilot study. Changes were made in the items' wording and application, which requires a face-to-face interview. It was not necessary to change the choices of answers. The Brazilian versions of the RABQ and RAAQ showed semantic and cultural equivalence to the original versions and are easy for the target population to understand. The two scales still require validity and reliability studies before use in the field.
NASA Astrophysics Data System (ADS)
Yan, Hong; Song, Xiangzhong; Tian, Kuangda; Chen, Yilin; Xiong, Yanmei; Min, Shungeng
2018-02-01
A novel method, mid-infrared (MIR) spectroscopy, which enables the determination of Chlorantraniliprole in Abamectin within minutes, is proposed. We further evaluate the prediction ability of four wavelength selection methods, including bootstrapping soft shrinkage approach (BOSS), Monte Carlo uninformative variable elimination (MCUVE), genetic algorithm partial least squares (GA-PLS) and competitive adaptive reweighted sampling (CARS) respectively. The results showed that BOSS method obtained the lowest root mean squared error of cross validation (RMSECV) (0.0245) and root mean squared error of prediction (RMSEP) (0.0271), as well as the highest coefficient of determination of cross-validation (Qcv2) (0.9998) and the coefficient of determination of test set (Q2test) (0.9989), which demonstrated that the mid infrared spectroscopy can be used to detect Chlorantraniliprole in Abamectin conveniently. Meanwhile, a suitable wavelength selection method (BOSS) is essential to conducting a component spectral analysis.
Arciniega, Luis M; González, Luis; Soares, Vítor; Ciulli, Stefania; Giannini, Marco
2009-11-01
The Work Values Scale EVAT (based on its initials in Spanish: Escala de Valores hacia el Trabajo) was created in 2000 to measure values in the work context. The instrument operationalizes the four higher-order-values of the Schwartz Theory (1992) through sixteen items focused on work scenarios. The questionnaire has been used among large samples of Mexican and Spanish individuals reporting adequate psychometric properties. The instrument has recently been translated into Portuguese and Italian, and subsequently used in a large-scale study with nurses in Portugal and in a sample of various occupations in Italy. The purpose of this research was to demonstrate the cross-cultural validity of the Work Values Scale EVAT in Spanish, Portuguese, and Italian. Our results suggest that the original Spanish version of the EVAT scale and the new Portuguese and Italian versions are equivalent.
Further cross-cultural validation of the theory of mental self-government.
Zhang, L F
1999-03-01
This study was designed to achieve two objectives. The 1st was to investigate the cross-cultural validity of the Thinking Styles Inventory (TSI; R. J. Sternberg & R. K. Wagner, 1992), which is based on the theory of mental self-government (R. J. Sternberg, 1988, 1990, 1997). The 2nd was to examine the relationships between thinking styles as assessed by the TSI and a number of student characteristics, including age, gender, college class level, work experience, and travel experience. One hundred fifty-one students from the University of Hong Kong participated in the study. Results indicated that the thinking styles evaluated by the TSI could be identified among the participants. Moreover, there were significant relationships between certain thinking styles, especially creativity-relevant styles and 3 student characteristics: age, work experience, and travel experience. Implications of these findings for teaching and learning in and outside the classroom are discussed.
Measuring Knowledge Integration Learning of Energy Topics: A two-year longitudinal study
NASA Astrophysics Data System (ADS)
Liu, Ou Lydia; Ryoo, Kihyun; Linn, Marcia C.; Sato, Elissa; Svihla, Vanessa
2015-05-01
Although researchers call for inquiry learning in science, science assessments rarely capture the impact of inquiry instruction. This paper reports on the development and validation of assessments designed to measure middle-school students' progress in gaining integrated understanding of energy while studying an inquiry-oriented curriculum. The assessment development was guided by the knowledge integration framework. Over 2 years of implementation, more than 4,000 students from 4 schools participated in the study, including a cross-sectional and a longitudinal cohort. Results from item response modeling analyses revealed that: (a) the assessments demonstrated satisfactory psychometric properties in terms of reliability and validity; (b) both the cross-sectional and longitudinal cohorts made progress on integrating their understanding energy concepts; and (c) among many factors (e.g. gender, grade, school, and home language) associated with students' science performance, unit implementation was the strongest predictor.
Investigation of Super Learner Methodology on HIV-1 Small Sample: Application on Jaguar Trial Data.
Houssaïni, Allal; Assoumou, Lambert; Marcelin, Anne Geneviève; Molina, Jean Michel; Calvez, Vincent; Flandre, Philippe
2012-01-01
Background. Many statistical models have been tested to predict phenotypic or virological response from genotypic data. A statistical framework called Super Learner has been introduced either to compare different methods/learners (discrete Super Learner) or to combine them in a Super Learner prediction method. Methods. The Jaguar trial is used to apply the Super Learner framework. The Jaguar study is an "add-on" trial comparing the efficacy of adding didanosine to an on-going failing regimen. Our aim was also to investigate the impact on the use of different cross-validation strategies and different loss functions. Four different repartitions between training set and validations set were tested through two loss functions. Six statistical methods were compared. We assess performance by evaluating R(2) values and accuracy by calculating the rates of patients being correctly classified. Results. Our results indicated that the more recent Super Learner methodology of building a new predictor based on a weighted combination of different methods/learners provided good performance. A simple linear model provided similar results to those of this new predictor. Slight discrepancy arises between the two loss functions investigated, and slight difference arises also between results based on cross-validated risks and results from full dataset. The Super Learner methodology and linear model provided around 80% of patients correctly classified. The difference between the lower and higher rates is around 10 percent. The number of mutations retained in different learners also varys from one to 41. Conclusions. The more recent Super Learner methodology combining the prediction of many learners provided good performance on our small dataset.
Correction of sampling bias in a cross-sectional study of post-surgical complications.
Fluss, Ronen; Mandel, Micha; Freedman, Laurence S; Weiss, Inbal Salz; Zohar, Anat Ekka; Haklai, Ziona; Gordon, Ethel-Sherry; Simchen, Elisheva
2013-06-30
Cross-sectional designs are often used to monitor the proportion of infections and other post-surgical complications acquired in hospitals. However, conventional methods for estimating incidence proportions when applied to cross-sectional data may provide estimators that are highly biased, as cross-sectional designs tend to include a high proportion of patients with prolonged hospitalization. One common solution is to use sampling weights in the analysis, which adjust for the sampling bias inherent in a cross-sectional design. The current paper describes in detail a method to build weights for a national survey of post-surgical complications conducted in Israel. We use the weights to estimate the probability of surgical site infections following colon resection, and validate the results of the weighted analysis by comparing them with those obtained from a parallel study with a historically prospective design. Copyright © 2012 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Steger, Stefan; Brenning, Alexander; Bell, Rainer; Petschko, Helene; Glade, Thomas
2016-06-01
Empirical models are frequently applied to produce landslide susceptibility maps for large areas. Subsequent quantitative validation results are routinely used as the primary criteria to infer the validity and applicability of the final maps or to select one of several models. This study hypothesizes that such direct deductions can be misleading. The main objective was to explore discrepancies between the predictive performance of a landslide susceptibility model and the geomorphic plausibility of subsequent landslide susceptibility maps while a particular emphasis was placed on the influence of incomplete landslide inventories on modelling and validation results. The study was conducted within the Flysch Zone of Lower Austria (1,354 km2) which is known to be highly susceptible to landslides of the slide-type movement. Sixteen susceptibility models were generated by applying two statistical classifiers (logistic regression and generalized additive model) and two machine learning techniques (random forest and support vector machine) separately for two landslide inventories of differing completeness and two predictor sets. The results were validated quantitatively by estimating the area under the receiver operating characteristic curve (AUROC) with single holdout and spatial cross-validation technique. The heuristic evaluation of the geomorphic plausibility of the final results was supported by findings of an exploratory data analysis, an estimation of odds ratios and an evaluation of the spatial structure of the final maps. The results showed that maps generated by different inventories, classifiers and predictors appeared differently while holdout validation revealed similar high predictive performances. Spatial cross-validation proved useful to expose spatially varying inconsistencies of the modelling results while additionally providing evidence for slightly overfitted machine learning-based models. However, the highest predictive performances were obtained for maps that explicitly expressed geomorphically implausible relationships indicating that the predictive performance of a model might be misleading in the case a predictor systematically relates to a spatially consistent bias of the inventory. Furthermore, we observed that random forest-based maps displayed spatial artifacts. The most plausible susceptibility map of the study area showed smooth prediction surfaces while the underlying model revealed a high predictive capability and was generated with an accurate landslide inventory and predictors that did not directly describe a bias. However, none of the presented models was found to be completely unbiased. This study showed that high predictive performances cannot be equated with a high plausibility and applicability of subsequent landslide susceptibility maps. We suggest that greater emphasis should be placed on identifying confounding factors and biases in landslide inventories. A joint discussion between modelers and decision makers of the spatial pattern of the final susceptibility maps in the field might increase their acceptance and applicability.
Spatio-temporal modeling of chronic PM 10 exposure for the Nurses' Health Study
NASA Astrophysics Data System (ADS)
Yanosky, Jeff D.; Paciorek, Christopher J.; Schwartz, Joel; Laden, Francine; Puett, Robin; Suh, Helen H.
2008-06-01
Chronic epidemiological studies of airborne particulate matter (PM) have typically characterized the chronic PM exposures of their study populations using city- or county-wide ambient concentrations, which limit the studies to areas where nearby monitoring data are available and which ignore within-city spatial gradients in ambient PM concentrations. To provide more spatially refined and precise chronic exposure measures, we used a Geographic Information System (GIS)-based spatial smoothing model to predict monthly outdoor PM10 concentrations in the northeastern and midwestern United States. This model included monthly smooth spatial terms and smooth regression terms of GIS-derived and meteorological predictors. Using cross-validation and other pre-specified selection criteria, terms for distance to road by road class, urban land use, block group and county population density, point- and area-source PM10 emissions, elevation, wind speed, and precipitation were found to be important determinants of PM10 concentrations and were included in the final model. Final model performance was strong (cross-validation R2=0.62), with little bias (-0.4 μg m-3) and high precision (6.4 μg m-3). The final model (with monthly spatial terms) performed better than a model with seasonal spatial terms (cross-validation R2=0.54). The addition of GIS-derived and meteorological predictors improved predictive performance over spatial smoothing (cross-validation R2=0.51) or inverse distance weighted interpolation (cross-validation R2=0.29) methods alone and increased the spatial resolution of predictions. The model performed well in both rural and urban areas, across seasons, and across the entire time period. The strong model performance demonstrates its suitability as a means to estimate individual-specific chronic PM10 exposures for large populations.
Schadl, Kornél; Vassar, Rachel; Cahill-Rowley, Katelyn; Yeom, Kristin W; Stevenson, David K; Rose, Jessica
2018-01-01
Advanced neuroimaging and computational methods offer opportunities for more accurate prognosis. We hypothesized that near-term regional white matter (WM) microstructure, assessed on diffusion tensor imaging (DTI), using exhaustive feature selection with cross-validation would predict neurodevelopment in preterm children. Near-term MRI and DTI obtained at 36.6 ± 1.8 weeks postmenstrual age in 66 very-low-birth-weight preterm neonates were assessed. 60/66 had follow-up neurodevelopmental evaluation with Bayley Scales of Infant-Toddler Development, 3rd-edition (BSID-III) at 18-22 months. Linear models with exhaustive feature selection and leave-one-out cross-validation computed based on DTI identified sets of three brain regions most predictive of cognitive and motor function; logistic regression models were computed to classify high-risk infants scoring one standard deviation below mean. Cognitive impairment was predicted (100% sensitivity, 100% specificity; AUC = 1) by near-term right middle-temporal gyrus MD, right cingulate-cingulum MD, left caudate MD. Motor impairment was predicted (90% sensitivity, 86% specificity; AUC = 0.912) by left precuneus FA, right superior occipital gyrus MD, right hippocampus FA. Cognitive score variance was explained (29.6%, cross-validated Rˆ2 = 0.296) by left posterior-limb-of-internal-capsule MD, Genu RD, right fusiform gyrus AD. Motor score variance was explained (31.7%, cross-validated Rˆ2 = 0.317) by left posterior-limb-of-internal-capsule MD, right parahippocampal gyrus AD, right middle-temporal gyrus AD. Search in large DTI feature space more accurately identified neonatal neuroimaging correlates of neurodevelopment.
Introduction of Total Variation Regularization into Filtered Backprojection Algorithm
NASA Astrophysics Data System (ADS)
Raczyński, L.; Wiślicki, W.; Klimaszewski, K.; Krzemień, W.; Kowalski, P.; Shopa, R. Y.; Białas, P.; Curceanu, C.; Czerwiński, E.; Dulski, K.; Gajos, A.; Głowacz, B.; Gorgol, M.; Hiesmayr, B.; Jasińska, B.; Kisielewska-Kamińska, D.; Korcyl, G.; Kozik, T.; Krawczyk, N.; Kubicz, E.; Mohammed, M.; Pawlik-Niedźwiecka, M.; Niedźwiecki, S.; Pałka, M.; Rudy, Z.; Sharma, N. G.; Sharma, S.; Silarski, M.; Skurzok, M.; Wieczorek, A.; Zgardzińska, B.; Zieliński, M.; Moskal, P.
In this paper we extend the state-of-the-art filtered backprojection (FBP) method with application of the concept of Total Variation regularization. We compare the performance of the new algorithm with the most common form of regularizing in the FBP image reconstruction via apodizing functions. The methods are validated in terms of cross-correlation coefficient between reconstructed and real image of radioactive tracer distribution using standard Derenzo-type phantom. We demonstrate that the proposed approach results in higher cross-correlation values with respect to the standard FBP method.
Lin, Ying-Tsong; Collis, Jon M; Duda, Timothy F
2012-11-01
An alternating direction implicit (ADI) three-dimensional fluid parabolic equation solution method with enhanced accuracy is presented. The method uses a square-root Helmholtz operator splitting algorithm that retains cross-multiplied operator terms that have been previously neglected. With these higher-order cross terms, the valid angular range of the parabolic equation solution is improved. The method is tested for accuracy against an image solution in an idealized wedge problem. Computational efficiency improvements resulting from the ADI discretization are also discussed.
Tuğay, Baki Umut; Tuğay, Nazan; Güney, Hande; Kınıklı, Gizem İrem; Yüksel, İnci; Atilla, Bülent
2016-01-01
The Oxford Knee Score (OKS) is a valid, short, self-administered, and site- specific outcome measure specifically developed for patients with knee arthroplasty. This study aimed to cross-culturally adapt and validate the OKS to be used in Turkish-speaking patients with osteoarthritis of the knee. The OKS was translated and culturally adapted according to the guidelines in the literature. Ninety-one patients (mean age: 55.89±7.85 years) with knee osteoarthritis participated in the study. Patients completed the Turkish version of the Oxford Knee Score (OKS-TR), Short-Form 36 Health Survey (SF-36), and Western Ontario and McMaster Universities Index (WOMAC) questionnaires. Internal consistency was tested using Cronbach's α coefficient. Patients completed the OKS-TR questionnaire twice in 7 days to determine the reproducibility. Correlation between the total results of both tests was determined by Spearman's correlation coefficient and intraclass correlation coefficients (ICC). Validity was assessed by calculating Spearman's correlation coefficient between the OKS, WOMAC, and SF-36 scores. Floor and ceiling effects were analyzed. Internal consistency was high (Cronbach's α: 0.90). The reproducibility tested by 2 different methods showed no significant difference (p>0.05). The construct validity analyses showed a significant correlation between the OKS and the other scores (p<0.05). There was no floor or ceiling effect in total OKS score. The OKS-TR is a reliable and valid measure for the self-assessment of pain and function in Turkish-speaking patients with osteoarthritis of the knee.
Validating LES for Jet Aeroacoustics
NASA Technical Reports Server (NTRS)
Bridges, James; Wernet, Mark P.
2011-01-01
Engineers charged with making jet aircraft quieter have long dreamed of being able to see exactly how turbulent eddies produce sound and this dream is now coming true with the advent of large eddy simulation (LES). Two obvious challenges remain: validating the LES codes at the resolution required to see the fluid-acoustic coupling, and the interpretation of the massive datasets that are produced. This paper addresses the former, the use of advanced experimental techniques such as particle image velocimetry (PIV) and Raman and Rayleigh scattering, to validate the computer codes and procedures used to create LES solutions. This paper argues that the issue of accuracy of the experimental measurements be addressed by cross-facility and cross-disciplinary examination of modern datasets along with increased reporting of internal quality checks in PIV analysis. Further, it argues that the appropriate validation metrics for aeroacoustic applications are increasingly complicated statistics that have been shown in aeroacoustic theory to be critical to flow-generated sound, such as two-point space-time velocity correlations. A brief review of data sources available is presented along with examples illustrating cross-facility and internal quality checks required of the data before it should be accepted for validation of LES.
1989-04-20
International business Machines Corporati,:i IBM Development System for the Ada Language, CMS/MVS Ada Cross Compiler, Version 2.1.1, Wright-Patterson AFB, IBM...VALIDATION SUMMARY REPORT: Certificate Number: 890420W1.10075 International Business Machines Corporation IBM Development System for the Ada Language CMS...command scripts provided by International Business Machines Corporation and reviewed by the validation team. The compiler was tested using all default
St Lawrence, Janet S; Seloilwe, Esther; Magowe, Mabel; Dithole, Kefalotse; Kgosikwena, Billy; Kokoro, Elija; Lesaane, Dipuo
2013-08-01
An evidence-based HIV prevention intervention was adapted for Botswana youth with qualitative interviews, input from an adolescent panel, and social validation. Qualitative interviews were conducted with 40 boys and girls ages 13-19. An adolescent panel then drafted scenarios reflecting social situations described in the interviews that posed risk for HIV. A social validation sample (N = 65) then indicated the prevalence and difficulty of each situation. Youth described informational needs, pressures to use alcohol and drugs, peer pressure for unprotected sex, and intergenerational sex initiations as risk-priming situations. From 17% to 57% of the social validation sample had personally experienced the situations drafted by the adolescent panel. There were no differences in the ratings of boys versus girls, but youth over age 16 more often reported that they had experienced these risky situations. The results were embedded into the intervention. Major changes to the intervention resulted from this three-phase process.
Van Iddekinge, Chad H; Putka, Dan J; Campbell, John P
2011-01-01
Although vocational interests have a long history in vocational psychology, they have received extremely limited attention within the recent personnel selection literature. We reconsider some widely held beliefs concerning the (low) validity of interests for predicting criteria important to selection researchers, and we review theory and empirical evidence that challenge such beliefs. We then describe the development and validation of an interests-based selection measure. Results of a large validation study (N = 418) reveal that interests predicted a diverse set of criteria—including measures of job knowledge, job performance, and continuance intentions—with corrected, cross-validated Rs that ranged from .25 to .46 across the criteria (mean R = .31). Interests also provided incremental validity beyond measures of general cognitive aptitude and facets of the Big Five personality dimensions in relation to each criterion. Furthermore, with a couple exceptions, the interest scales were associated with small to medium subgroup differences, which in most cases favored women and racial minorities. Taken as a whole, these results appear to call into question the prevailing thought that vocational interests have limited usefulness for selection.
Absorption in Sport: A Cross-Validation Study
Koehn, Stefan; Stavrou, Nektarios A. M.; Cogley, Jeremy; Morris, Tony; Mosek, Erez; Watt, Anthony P.
2017-01-01
Absorption has been identified as readiness for experiences of deep involvement in the task. Conceptually, absorption is a key psychological construct, incorporating experiential, cognitive, and motivational components. Although, no operationalization of the construct has been provided to facilitate research in this area, the purpose of this research was the development and examination of the psychometric properties of a sport-specific measure of absorption that evolved from the use of the modified Tellegen Absorption Scale (MODTAS; Jamieson, 2005) in mainstream psychology. The study aimed to provide evidence of the psychometric properties, reliability, and validity of the Measure of Absorption in Sport Contexts (MASCs). The psychometric examination included a calibration sample from Scotland and a cross-validation sample from Australia using a cross-sectional design. The item pool was developed based on existing items from the modified Tellegen Absorption Scale (Jamieson, 2005). The MODTAS items were reworded and translated into a sport context. The Scottish sample consisted of 292 participants and the Australian sample of 314 participants. Congeneric model testing and confirmatory factor analysis for both samples and multi-group invariance testing across samples was used. In the cross-validation sample the MASC subscales showed acceptable internal consistency and construct reliability (≥0.70). Excellent fit indices were found for the final 18-item, six-factor measure in the cross-validation sample, χ(120)2 = 197.486, p < 0.001; CFI = 0.957; TLI = 0.945; RMSEA = 0.045; SRMR = 0.044. Multi-group invariance testing revealed no differences in item meaning, except for two items. The MASC and the Dispositional Flow Scale-2 showed moderate-to-strong positive correlations in both samples, r = 0.38, p < 0.001 and r = 0.42, p < 0.001, supporting the external validity of the MASC. This article provides initial evidence in support of the psychometric properties, reliability, and validity of the sport-specific measure of absorption. The MASC provides rich research opportunities in sport psychology that can enhance the theoretical understanding between absorption and related constructs and facilitate future intervention studies. PMID:28883802
Perceptual load interacts with stimulus processing across sensory modalities.
Klemen, J; Büchel, C; Rose, M
2009-06-01
According to perceptual load theory, processing of task-irrelevant stimuli is limited by the perceptual load of a parallel attended task if both the task and the irrelevant stimuli are presented to the same sensory modality. However, it remains a matter of debate whether the same principles apply to cross-sensory perceptual load and, more generally, what form cross-sensory attentional modulation in early perceptual areas takes in humans. Here we addressed these questions using functional magnetic resonance imaging. Participants undertook an auditory one-back working memory task of low or high perceptual load, while concurrently viewing task-irrelevant images at one of three object visibility levels. The processing of the visual and auditory stimuli was measured in the lateral occipital cortex (LOC) and auditory cortex (AC), respectively. Cross-sensory interference with sensory processing was observed in both the LOC and AC, in accordance with previous results of unisensory perceptual load studies. The present neuroimaging results therefore warrant the extension of perceptual load theory from a unisensory to a cross-sensory context: a validation of this cross-sensory interference effect through behavioural measures would consolidate the findings.
Safety assessment on pedestrian crossing environments using MLS data.
Soilán, Mario; Riveiro, Belén; Sánchez-Rodríguez, Ana; Arias, Pedro
2018-02-01
In the framework of infrastructure analysis and maintenance in an urban environment, it is important to address the safety of every road user. This paper presents a methodology for the evaluation of several safety indicators on pedestrian crossing environments using geometric and radiometric information extracted from 3D point clouds collected by a Mobile Mapping System (MMS). The methodology is divided in four main modules which analyze the accessibility of the crossing area, the presence of traffic lights and traffic signs, and the visibility between a driver and a pedestrian on the proximities of a pedestrian crossing. The outputs of the analysis are exported to a Geographic Information System (GIS) where they are visualized and can be further processed in the context of city management. The methodology has been tested on approximately 30 pedestrian crossings in cluttered urban environments of two different cities. Results show that MMS are a valid mean to assess the safety of a specific urban environment, regarding its geometric conditions. Remarkable results are presented on traffic light classification, with a global F-score close to 95%. Copyright © 2017 Elsevier Ltd. All rights reserved.
Validity of one-repetition maximum predictive equations in men with spinal cord injury.
Ribeiro Neto, F; Guanais, P; Dornelas, E; Coutinho, A C B; Costa, R R G
2017-10-01
Cross-sectional study. The study aimed (a) to test the cross-validation of current one-repetition maximum (1RM) predictive equations in men with spinal cord injury (SCI); (b) to compare the current 1RM predictive equations to a newly developed equation based on the 4- to 12-repetition maximum test (4-12RM). SARAH Rehabilitation Hospital Network, Brasilia, Brazil. Forty-five men aged 28.0 years with SCI between C6 and L2 causing complete motor impairment were enrolled in the study. Volunteers were tested, in a random order, in 1RM test or 4-12RM with 2-3 interval days. Multiple regression analysis was used to generate an equation for predicting 1RM. There were no significant differences between 1RM test and the current predictive equations. ICC values were significant and were classified as excellent for all current predictive equations. The predictive equation of Lombardi presented the best Bland-Altman results (0.5 kg and 12.8 kg for mean difference and interval range around the differences, respectively). The two created equation models for 1RM demonstrated the same and a high adjusted R 2 (0.971, P<0.01), but different SEE of measured 1RM (2.88 kg or 5.4% and 2.90 kg or 5.5%). All 1RM predictive equations are accurate to assess individuals with SCI at the bench press exercise. However, the predictive equation of Lombardi presented the best associated cross-validity results. A specific 1RM prediction equation was also elaborated for individuals with SCI. The created equation should be tested in order to verify whether it presents better accuracy than the current ones.
Machine Learning Interface for Medical Image Analysis.
Zhang, Yi C; Kagen, Alexander C
2017-10-01
TensorFlow is a second-generation open-source machine learning software library with a built-in framework for implementing neural networks in wide variety of perceptual tasks. Although TensorFlow usage is well established with computer vision datasets, the TensorFlow interface with DICOM formats for medical imaging remains to be established. Our goal is to extend the TensorFlow API to accept raw DICOM images as input; 1513 DaTscan DICOM images were obtained from the Parkinson's Progression Markers Initiative (PPMI) database. DICOM pixel intensities were extracted and shaped into tensors, or n-dimensional arrays, to populate the training, validation, and test input datasets for machine learning. A simple neural network was constructed in TensorFlow to classify images into normal or Parkinson's disease groups. Training was executed over 1000 iterations for each cross-validation set. The gradient descent optimization and Adagrad optimization algorithms were used to minimize cross-entropy between the predicted and ground-truth labels. Cross-validation was performed ten times to produce a mean accuracy of 0.938 ± 0.047 (95 % CI 0.908-0.967). The mean sensitivity was 0.974 ± 0.043 (95 % CI 0.947-1.00) and mean specificity was 0.822 ± 0.207 (95 % CI 0.694-0.950). We extended the TensorFlow API to enable DICOM compatibility in the context of DaTscan image analysis. We implemented a neural network classifier that produces diagnostic accuracies on par with excellent results from previous machine learning models. These results indicate the potential role of TensorFlow as a useful adjunct diagnostic tool in the clinical setting.
Cross-correlation Doppler global velocimetry (CC-DGV)
NASA Astrophysics Data System (ADS)
Cadel, Daniel R.; Lowe, K. Todd
2015-08-01
A flow velocimetry method, cross-correlation Doppler global velocimetry (CC-DGV), is presented as a robust, simplified, and high dynamic range implementation of the Doppler global/planar Doppler velocimetry technique. A sweep of several gigahertz of the vapor absorption spectrum is used for each velocity sample, with signals acquired from both Doppler-shifted scattered light within the flow and a non-Doppler shifted reference beam. Cross-correlation of these signals yields the Doppler shift between them, averaged over the duration of the scan. With presently available equipment, velocities from 0 ms-1 to over 3000 ms-1 can notionally be measured simultaneously, making the technique ideal for high speed flows. The processing routine is shown to be robust against large changes in the vapor pressure of the iodine cell, benefiting performance of the system in facilities where ambient conditions cannot be easily regulated. Validation of the system was performed with measurements of a model wind turbine blade boundary layer made in a 1.83 m by 1.83 m subsonic wind tunnel for which laser Doppler velocimetry (LDV) measurements were acquired alongside the CC-DGV results. CC-DGV uncertainties of ±1.30 ms-1, ±0.64 ms-1, and ±1.11 ms-1 were determined for the orthogonal stream-wise, transverse-horizontal, and transverse-vertical velocity components, and root-mean-square deviations of 2.77 ms-1 and 1.34 ms-1 from the LDV validation results were observed for Reynolds numbers of 1.5 million and 2 million, respectively. Volumetric mean velocity measurements are also presented for a supersonic jet, with velocity uncertainties of ±4.48 ms-1, ±16.93 ms-1, and ±0.50 ms-1 for the orthogonal components, and self-validation done by collapsing the data with a physical scaling.
Richardson, Michelle; Katsakou, Christina; Torres-González, Francisco; Onchev, George; Kallert, Thomas; Priebe, Stefan
2011-06-30
Patients' views of inpatient care need to be assessed for research and routine evaluation. For this a valid instrument is required. The Client Assessment of Treatment Scale (CAT) has been used in large scale international studies, but its psychometric properties have not been well established. The structural validity of the CAT was tested among involuntary inpatients with psychosis. Data from locations in three separate European countries (England, Spain and Bulgaria) were collected. The factorial validity was initially tested using single sample confirmatory factor analyses in each country. Subsequent multi-sample analyses were used to test for invariance of the factor loadings, and factor variances across the countries. Results provide good initial support for the factorial validity and invariance of the CAT scores. Future research is needed to cross-validate these findings and to generalise them to other countries, treatment settings, and patient populations. Copyright © 2011 Elsevier Ltd. All rights reserved.
Development and Validation of a Unidimensional Maltreatment Scale in the Add Health Data Set
ERIC Educational Resources Information Center
Marszalek, Jacob M.; Hamilton, Jessica L.
2012-01-01
Four maltreatment items were examined from Wave III (N = 13,516) of the National Longitudinal Study of Adolescent Health. Item analysis, confirmatory factor analysis, cross-validation, reliability estimates, and convergent validity coefficients strongly supported the validity of using the four items as a unidimensional composite. Implications for…
Machine Learning Meta-analysis of Large Metagenomic Datasets: Tools and Biological Insights.
Pasolli, Edoardo; Truong, Duy Tin; Malik, Faizan; Waldron, Levi; Segata, Nicola
2016-07-01
Shotgun metagenomic analysis of the human associated microbiome provides a rich set of microbial features for prediction and biomarker discovery in the context of human diseases and health conditions. However, the use of such high-resolution microbial features presents new challenges, and validated computational tools for learning tasks are lacking. Moreover, classification rules have scarcely been validated in independent studies, posing questions about the generality and generalization of disease-predictive models across cohorts. In this paper, we comprehensively assess approaches to metagenomics-based prediction tasks and for quantitative assessment of the strength of potential microbiome-phenotype associations. We develop a computational framework for prediction tasks using quantitative microbiome profiles, including species-level relative abundances and presence of strain-specific markers. A comprehensive meta-analysis, with particular emphasis on generalization across cohorts, was performed in a collection of 2424 publicly available metagenomic samples from eight large-scale studies. Cross-validation revealed good disease-prediction capabilities, which were in general improved by feature selection and use of strain-specific markers instead of species-level taxonomic abundance. In cross-study analysis, models transferred between studies were in some cases less accurate than models tested by within-study cross-validation. Interestingly, the addition of healthy (control) samples from other studies to training sets improved disease prediction capabilities. Some microbial species (most notably Streptococcus anginosus) seem to characterize general dysbiotic states of the microbiome rather than connections with a specific disease. Our results in modelling features of the "healthy" microbiome can be considered a first step toward defining general microbial dysbiosis. The software framework, microbiome profiles, and metadata for thousands of samples are publicly available at http://segatalab.cibio.unitn.it/tools/metaml.
Cross-cultural adaptation and validation of the Behcet’s Disease Current Activity Form in Korea
Choi, Hyo Jin; Seo, Mi Ryoung; Ryu, Hee Jung; Baek, Han Joo
2015-01-01
Background/Aims: This study was undertaken to perform a cross-cultural adaptation of the Behcet’s Disease Current Activity Form (BDCAF, version 2006) questionnaire to the Korean language and to evaluate its reliability and validity in a population of Korean patients with Behcet’s disease (BD). Methods: A cross-cultural study was conducted among patients with BD who attended our rheumatology clinic between November 2012 and March 2013. There were 11 males and 35 females in the group. The mean age of the participants was 48.5 years and the mean disease duration was 6.4 years. The first BDCAF questionnaire was completed on arrival and the second assessment was performed 20 minutes later by a different physician. The test-retest reliability was analyzed by computing κ statistics. Kappa scores of > 0.6 indicated a good agreement. To assess the validity, we compared the total BDCAF score with the patient’s/clinician’s perception of disease activity and the Korean version of the Behcet’s Disease Quality of Life (BDQOL). Results: For the test-retest reliability, good agreements were achieved on items such as headache, oral/genital ulceration, erythema, skin pustules, arthralgia, nausea/vomiting/abdominal pain, and diarrhea with altered/frank blood per rectum. Moderate agreement was observed for eye and nervous system involvement. We achieved a fair agreement for arthritis and major vessel involvement. Significant correlations were obtained between the total BDCAF score with the BDQOL and the patient’s/clinician’s perception of disease activity p < 0.05). Conclusions: The Korean version of the BDCAF is a reliable and valid instrument for measuring current disease activity in Korean BD patients. PMID:26354066
Hravnak, Marilyn; Chen, Lujie; Dubrawski, Artur; Bose, Eliezer; Clermont, Gilles; Pinsky, Michael R.
2015-01-01
PURPOSE Huge hospital information system databases can be mined for knowledge discovery and decision support, but artifact in stored non-invasive vital sign (VS) high-frequency data streams limits its use. We used machine-learning (ML) algorithms trained on expert-labeled VS data streams to automatically classify VS alerts as real or artifact, thereby “cleaning” such data for future modeling. METHODS 634 admissions to a step-down unit had recorded continuous noninvasive VS monitoring data (heart rate [HR], respiratory rate [RR], peripheral arterial oxygen saturation [SpO2] at 1/20Hz., and noninvasive oscillometric blood pressure [BP]) Time data were across stability thresholds defined VS event epochs. Data were divided Block 1 as the ML training/cross-validation set and Block 2 the test set. Expert clinicians annotated Block 1 events as perceived real or artifact. After feature extraction, ML algorithms were trained to create and validate models automatically classifying events as real or artifact. The models were then tested on Block 2. RESULTS Block 1 yielded 812 VS events, with 214 (26%) judged by experts as artifact (RR 43%, SpO2 40%, BP 15%, HR 2%). ML algorithms applied to the Block 1 training/cross-validation set (10-fold cross-validation) gave area under the curve (AUC) scores of 0.97 RR, 0.91 BP and 0.76 SpO2. Performance when applied to Block 2 test data was AUC 0.94 RR, 0.84 BP and 0.72 SpO2). CONCLUSIONS ML-defined algorithms applied to archived multi-signal continuous VS monitoring data allowed accurate automated classification of VS alerts as real or artifact, and could support data mining for future model building. PMID:26438655
Abanto, Jenny; Albites, Ursula; Bönecker, Marcelo; Paiva, Saul M; Castillo, Jorge L; Aguilar-Gálvez, Denisse
2015-12-01
The lack of a Family Impact Scale (FIS) in Spanish language limits its use as an indicator in Spanish-speaking countries and precludes comparisons with data from other cultural and ethnic groups. The purpose of this study was therefore to adapt the FIS cross-culturally to the Peruvian Spanish language and assess its reliability and validity. In order to translate and adapt the FIS cross-culturally, it was answered by 60 parents in two pilot tests, after which it was tested on 200 parents of children aged 11 to 14 years who were clinically examined for dental caries experience and malocclusions. Internal consistency was assessed by Cronbach's alpha coefficient while repeat administration of the FIS on the same 200 parents enabled the test-retest reliability to be assessed via intraclass correlation coefficient (ICC). Construct and discriminant validity were based on associations of the FIS with global ratings of oral health and clinical groups, respectively. Mean (standard deviation) FIS total score was 5.20 (5.86). Internal consistency was confirmed by Cronbach's alpha 0.84. Test-retest reliability revealed excellent reproducibility (ICC = 0.96). Construct validity was good, demonstrating statistically significant associations between total FIS score and global ratings of oral health (p=0.007) and overall wellbeing (p=0.002), as well as for the subscale scores (p<0.05) with exception of the financial burden subscale. The FIS was also able to discriminate between children with and without dental caries experience and malocclusions (p<0.05). Satisfactory psychometric results for the Peruvian Spanish FIS confirm it as a reliable, valid instrument for assessing the impact on the family caused by children's oral conditions. Sociedad Argentina de Investigación Odontológica.
Gallasch, Cristiane Helena; Alexandre, Neusa Maria Costa; Amick, Benjamin
2007-12-01
The study objectives were to translate and adapt the Work Role Functioning Questionnaire (WRFQ) into the Brazilian Portuguese language and evaluate its reliability in patients experiencing musculoskeletal disorders. The cross-cultural adaptation was performed according to the internationally recommended methodology, using the following guidelines: translation, back-translation, revision by a committee, and pretest. At first, the questionnaire was independently translated by two bilingual translators, who had Portuguese as their mother language. Subsequently, two other translators whose mother language was English did the back-translation. A committee composed of five specialists revised and compared the translations obtained, developing the final version for pretest application. The pretest was carried out with 30 patients experiencing musculoskeletal disorders. Psychometric properties were evaluated by administering the questionnaire to 105 subjects with musculoskeletal disorders and receiving physical therapy treatment. The reliability was estimated through stability and homogeneity assessment. The construct validity was tested comparing subjects experiencing musculoskeletal disorders to healthy workers. The results indicated good content validity and internal consistency (Cronbach alpha = 0.95). Cronbach alpha for each scale was >0.85, except for the social demand scale. The Intraclass Correlation Coefficient for the test-retest reliability was satisfactory for mental demands (ICC = 0.68) and excellent for the others (0.82-0.91). In relation to the construct validity, the mean score obtained for each scale was lower for physical, work scheduling, and output demands in the subjects with musculoskeletal disorders. There was a significant difference (p < 0.001) between the groups in comparison to work scheduling, physical, and output demands. The data showed that the cross-cultural adaptation process was successful and the adapted instrument demonstrated psychometric properties making it reliable to use in Brazilian culture.
Kievit, Rogier F; Hoes, Arno W; Bots, Michiel L; van Riet, Evelien ES; van Mourik, Yvonne; Bertens, Loes CM; Boonman-de Winter, Leandra JM; den Ruijter, Hester M; Rutten, Frans H
2018-01-01
Background Prevalence of undetected heart failure in older individuals is high in the community, with patients being at increased risk of morbidity and mortality due to the chronic and progressive nature of this complex syndrome. An essential, yet currently unavailable, strategy to pre-select candidates eligible for echocardiography to confirm or exclude heart failure would identify patients earlier, enable targeted interventions and prevent disease progression. The aim of this study was therefore to develop and validate such a model that can be implemented clinically. Methods and results Individual patient data from four primary care screening studies were analysed. From 1941 participants >60 years old, 462 were diagnosed with heart failure, according to criteria of the European Society of Cardiology heart failure guidelines. Prediction models were developed in each cohort followed by cross-validation, omitting each of the four cohorts in turn. The model consisted of five independent predictors; age, history of ischaemic heart disease, exercise-related shortness of breath, body mass index and a laterally displaced/broadened apex beat, with no significant interaction with sex. The c-statistic ranged from 0.70 (95% confidence interval (CI) 0.64–0.76) to 0.82 (95% CI 0.78–0.87) at cross-validation and the calibration was reasonable with Observed/Expected ratios ranging from 0.86 to 1.15. The clinical model improved with the addition of N-terminal pro B-type natriuretic peptide with the c-statistic increasing from 0.76 (95% CI 0.70–0.81) to 0.89 (95% CI 0.86–0.92) at cross-validation. Conclusion Easily obtainable patient characteristics can select older men and women from the community who are candidates for echocardiography to confirm or refute heart failure. PMID:29327942
Kievit, Rogier F; Gohar, Aisha; Hoes, Arno W; Bots, Michiel L; van Riet, Evelien Es; van Mourik, Yvonne; Bertens, Loes Cm; Boonman-de Winter, Leandra Jm; den Ruijter, Hester M; Rutten, Frans H
2018-03-01
Background Prevalence of undetected heart failure in older individuals is high in the community, with patients being at increased risk of morbidity and mortality due to the chronic and progressive nature of this complex syndrome. An essential, yet currently unavailable, strategy to pre-select candidates eligible for echocardiography to confirm or exclude heart failure would identify patients earlier, enable targeted interventions and prevent disease progression. The aim of this study was therefore to develop and validate such a model that can be implemented clinically. Methods and results Individual patient data from four primary care screening studies were analysed. From 1941 participants >60 years old, 462 were diagnosed with heart failure, according to criteria of the European Society of Cardiology heart failure guidelines. Prediction models were developed in each cohort followed by cross-validation, omitting each of the four cohorts in turn. The model consisted of five independent predictors; age, history of ischaemic heart disease, exercise-related shortness of breath, body mass index and a laterally displaced/broadened apex beat, with no significant interaction with sex. The c-statistic ranged from 0.70 (95% confidence interval (CI) 0.64-0.76) to 0.82 (95% CI 0.78-0.87) at cross-validation and the calibration was reasonable with Observed/Expected ratios ranging from 0.86 to 1.15. The clinical model improved with the addition of N-terminal pro B-type natriuretic peptide with the c-statistic increasing from 0.76 (95% CI 0.70-0.81) to 0.89 (95% CI 0.86-0.92) at cross-validation. Conclusion Easily obtainable patient characteristics can select older men and women from the community who are candidates for echocardiography to confirm or refute heart failure.
Duarte Bonini Campos, J A; Dias do Prado, C
2012-01-01
The cross-cultural adaptation of the Patient-Generated Subjective Global Assessment is important so it can be used with confidence in Portuguese language. To perform a cross-cultural adaptation of the Portuguese version of the Patient-Generated Subjective Global Assessment and to estimate its intrarater reliability. This is a validation study. Face Validity was classified by 17 health professionals and 10 Portuguese language specialists. Idiomatic, semantic, cultural and conceptual equivalences were analyzed. The questionnaire was completed by 20 patients of the Amaral Carvalho Hospital (Jaú, São Paulo, Brazil) in order to verify the Comprehension Index of each item. Therefore, 27 committee members classified each item into "essential", "useful, but not essential" and "not necessary", in order to calculate the Content Validity Ratio. After, this version of the questionnaire was applied twice to 62 patients of the hospital cited above. The intrarater reliability of the nutritional status analyzed by Patient-Generated Subjective Global Assessment was estimated by Kappa statistics. The Portuguese version of the Patient-Generated Subjective Global Assessment presented 10 incomprehensible expressions. The items "a year ago weight" and "dry mouth symptom" presented the lowest Content Validity Ratio. Substantial intrarater reliability (k = 0.78, p = 0.001) was observed. The cross-cultural adaptation of the Portuguese version of the Patient-Generated Subjective Global Assessment became simple and understandable for Brazilian patients. Thus, this version of the Patient-Generated Subjective Global Assessment was considered a valid and a reliable method.
ERIC Educational Resources Information Center
Zhu, Zheng; Chen, Peijie; Zhuang, Jie
2013-01-01
Purpose: The purpose of this study was to develop and cross-validate an equation based on ActiGraph accelerometer GT3X output to predict children and youth's energy expenditure (EE) of physical activity (PA). Method: Participants were 367 Chinese children and youth (179 boys and 188 girls, aged 9 to 17 years old) who wore 1 ActiGraph GT3X…
NASA Astrophysics Data System (ADS)
Cao, Guangxi; Zhang, Minjia; Li, Qingchen
2017-04-01
This study focuses on multifractal detrended cross-correlation analysis of the different volatility intervals of Mainland China, US, and Hong Kong stock markets. A volatility-constrained multifractal detrended cross-correlation analysis (VC-MF-DCCA) method is proposed to study the volatility conductivity of Mainland China, US, and Hong Kong stock markets. Empirical results indicate that fluctuation may be related to important activities in real markets. The Hang Seng Index (HSI) stock market is more influential than the Shanghai Composite Index (SCI) stock market. Furthermore, the SCI stock market is more influential than the Dow Jones Industrial Average stock market. The conductivity between the HSI and SCI stock markets is the strongest. HSI was the most influential market in the large fluctuation interval of 1991 to 2014. The autoregressive fractionally integrated moving average method is used to verify the validity of VC-MF-DCCA. Results show that VC-MF-DCCA is effective.
Jalenques, Isabelle; Guiguet-Auclair, Candy; Derost, Philippe; Joubert, Pauline; Foures, Louis; Hartmann, Andreas; Muellner, Julia; Rondepierre, Fabien
2018-03-01
The Motor tic, Obsessions and compulsions, Vocal tic Evaluation Survey (MOVES) is a self-report scale suggested as a severity scale for tics and related sensory phenomena observed in Gilles de la Tourette syndrome (GTS) and recommended as a screening instrument by the Committee on Rating Scale Development of the International Parkinson's Disease and Movement Disorder Society. To cross-culturally adapt a French version of the MOVES and to evaluate its psychometric properties. After the cross-cultural adaptation of the MOVES, we assessed its psychometric properties in 53 patients aged 12-16 years and in 54 patients aged 16 years and above: reliability and construct validity (relationships between items and scales), internal consistency and concurrent validity with the Yale Global Tic Severity Scale (YGTSS) and the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) or the auto-Yale-Brown scale. The results showed very good acceptability with response rates greater than 92%, good internal consistency (Cronbach's alpha ranging from 0.62 and 0.89) and good test-retest reliability (ICCs ranging from 0.59 to 0.91). Concurrent validity with the YGTSS, CY-BOCS and auto-Yale-Brown scales showed strong expected correlations. The cut-off points tested for diagnostic performance gave satisfactory values of sensitivity, specificity, and positive and negative predictive values. Our study provides evidence of the good psychometric properties of the French version of the MOVES. The cross-cultural adaptation of this specific instrument will allow investigators to include French-speaking persons with GTS aged 12 years and over in national and international collaboration research projects.
NASA Astrophysics Data System (ADS)
Samala, Ravi K.; Chan, Heang-Ping; Hadjiiski, Lubomir; Helvie, Mark A.; Richter, Caleb; Cha, Kenny
2018-02-01
We propose a cross-domain, multi-task transfer learning framework to transfer knowledge learned from non-medical images by a deep convolutional neural network (DCNN) to medical image recognition task while improving the generalization by multi-task learning of auxiliary tasks. A first stage cross-domain transfer learning was initiated from ImageNet trained DCNN to mammography trained DCNN. 19,632 regions-of-interest (ROI) from 2,454 mass lesions were collected from two imaging modalities: digitized-screen film mammography (SFM) and full-field digital mammography (DM), and split into training and test sets. In the multi-task transfer learning, the DCNN learned the mass classification task simultaneously from the training set of SFM and DM. The best transfer network for mammography was selected from three transfer networks with different number of convolutional layers frozen. The performance of single-task and multitask transfer learning on an independent SFM test set in terms of the area under the receiver operating characteristic curve (AUC) was 0.78+/-0.02 and 0.82+/-0.02, respectively. In the second stage cross-domain transfer learning, a set of 12,680 ROIs from 317 mass lesions on DBT were split into validation and independent test sets. We first studied the data requirements for the first stage mammography trained DCNN by varying the mammography training data from 1% to 100% and evaluated its learning on the DBT validation set in inference mode. We found that the entire available mammography set provided the best generalization. The DBT validation set was then used to train only the last four fully connected layers, resulting in an AUC of 0.90+/-0.04 on the independent DBT test set.
Jahn, Beate; Rochau, Ursula; Kurzthaler, Christina; Paulden, Mike; Kluibenschädl, Martina; Arvandi, Marjan; Kühne, Felicitas; Goehler, Alexander; Krahn, Murray D; Siebert, Uwe
2016-04-01
Breast cancer is the most common malignancy among women in developed countries. We developed a model (the Oncotyrol breast cancer outcomes model) to evaluate the cost-effectiveness of a 21-gene assay when used in combination with Adjuvant! Online to support personalized decisions about the use of adjuvant chemotherapy. The goal of this study was to perform a cross-model validation. The Oncotyrol model evaluates the 21-gene assay by simulating a hypothetical cohort of 50-year-old women over a lifetime horizon using discrete event simulation. Primary model outcomes were life-years, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs). We followed the International Society for Pharmacoeconomics and Outcomes Research-Society for Medical Decision Making (ISPOR-SMDM) best practice recommendations for validation and compared modeling results of the Oncotyrol model with the state-transition model developed by the Toronto Health Economics and Technology Assessment (THETA) Collaborative. Both models were populated with Canadian THETA model parameters, and outputs were compared. The differences between the models varied among the different validation end points. The smallest relative differences were in costs, and the greatest were in QALYs. All relative differences were less than 1.2%. The cost-effectiveness plane showed that small differences in the model structure can lead to different sets of nondominated test-treatment strategies with different efficiency frontiers. We faced several challenges: distinguishing between differences in outcomes due to different modeling techniques and initial coding errors, defining meaningful differences, and selecting measures and statistics for comparison (means, distributions, multivariate outcomes). Cross-model validation was crucial to identify and correct coding errors and to explain differences in model outcomes. In our comparison, small differences in either QALYs or costs led to changes in ICERs because of changes in the set of dominated and nondominated strategies. © The Author(s) 2015.
Lohrer, Heinz; Nauck, Tanja
2011-03-01
Clinical measurement study. To cross-culturally adapt and validate the Victorian Institute of Sports Assessment Patellar Tendinopathy Questionnaire (VISA-P) for German-speaking patients. Like most questionnaires, the VISA-P was developed for English-speaking patients. There is a need to adapt the scale for German-speaking patients and thereby add to the total body of psychometric evidence relating to this instrument. The VISA-P questionnaire was translated and cross-culturally adapted into German (VISA-P-G) in 6 steps: translation, synthesis, back translation, expert committee review, pretesting, and advisory committee appraisal. The psychometric properties of the VISA-P-G were determined using 23 patients with patellar tendinopathy and 57 active healthy persons (32 sport students and 25 basketball players). Reliability was evaluated by applying the questionnaire twice within a week to all 80 participants. Known group validity was calculated using a 1-way analysis of variance. Additionally, VISA-P-G results were correlated with the Blazina classification system for patellar tendinopathy, using the Spearman rank correlation coefficient. VISA-P-G ratings from the present study groups were further compared with respective data published in the original English, Dutch, and Swedish versions by a 2-sample t test. Internal consistency for the individual items of the questionnaire was determined within the patient group using a Cronbach alpha. Test-retest revealed excellent reliability for the patient and the asymptomatic control group (ICC = 0.88 and 0.87, respectively). Internal consistency for the patients was 0.88. Concurrent validity was almost perfect (ρ = -0.81; P<.001). The VISA-P-G is a reliable and valid questionnaire for the self-assessment of pain, symptoms, and function in German-speaking patients with patellar tendinopathy. Its psychometric properties are comparable with the original English and international adaptations (Swedish, Dutch, and Italian).
Ko, Jupil; Rosen, Adam B; Brown, Cathleen N
2017-09-12
To cross-culturally adapt the Identification Functional Ankle Instability for use with Korean-speaking participants. The English version of the IdFAI was cross-culturally adapted into Korean based on the guidelines. The psychometric properties in the Korean version of the IdFAI were measured for test-retest reliability, internal consistency, criterion-related validity, discriminative validity, and measurement error 181 native Korean-speakers. Intra-class correlation coefficients (ICC 2,1 ) between the English and Korean versions of the IdFAI for test-retest reliability was 0.98 (standard error of measurement = 1.41). The Cronbach's alpha coefficient was 0.89 for the Korean versions of IdFAI. The Korean versions of the IdFAI had a strong correlation with the SF-36 (r s = -0.69, p < .001) and the Korean version of the Cumberland Ankle Instability Tool (r s = -0.65, p < .001). The cutoff score of >10 was the optimal cutoff score to distinguish between the group memberships. The minimally detectable change of the Korean versions of the IdFAI score was 3.91. The Korean versions of the IdFAI have shown to be an excellent, reliable, and valid instrument. The Korean versions of the IdFAI can be utilized to assess the presence of Chronic Ankle Instability by researchers and clinicians working among Korean-speaking populations. Implications for rehabilitation The high recurrence rate of sprains may result into Chronic Ankle Instability (CAI). The Identification of Functional Ankle Instability Tool (IdFAI) has been validated and recommended to identify patients with Chronic Ankle Instability (CAI). The Korean version of the Identification of Functional Ankle Instability Tool (IdFAI) may be also recommend to researchers and clinicians for assessing the presence of Chronic Ankle Instability (CAI) in Korean-speaking population.
Structure formation beyond shell-crossing: nonperturbative expansions and late-time attractors
NASA Astrophysics Data System (ADS)
Pietroni, Massimo
2018-06-01
Structure formation in 1+1 dimensions is considered, with emphasis on the effects of shell-crossing. The breakdown of the perturbative expansion beyond shell-crossing is discussed, and it is shown, in a simple example, that the perturbative series can be extended to a transseries including nonperturbative terms. The latter converges to the exact result well beyond the range of validity of perturbation theory. The crucial role of the divergences induced by shell-crossing is discussed. They provide constraints on the structure of the transseries and act as a bridge between the perturbative and the nonperturbative sectors. Then, we show that the dynamics in the deep multistreaming regime is governed by attractors. In the case of simple initial conditions, these attractors coincide with the asymptotic configurations of the adhesion model, but in general they may differ. These results are applied to a cosmological setting, and an algorithm to build the attractor solution starting from the Zel'dovich approximation is developed. Finally, this algorithm is applied to the search of `haloes' and the results are compared with those obtained from the exact dynamical equations.
Numerical Analysis of a Pulse Detonation Cross Flow Heat Load Experiment
NASA Technical Reports Server (NTRS)
Paxson, Daniel E.; Naples, Andrew .; Hoke, John L.; Schauer, Fred
2011-01-01
A comparison between experimentally measured and numerically simulated, time-averaged, point heat transfer rates in a pulse detonation (PDE) engine is presented. The comparison includes measurements and calculations for heat transfer to a cylinder in crossflow and to the tube wall itself using a novel spool design. Measurements are obtained at several locations and under several operating conditions. The measured and computed results are shown to be in substantial agreement, thereby validating the modeling approach. The model, which is based in computational fluid dynamics (CFD) is then used to interpret the results. A preheating of the incoming fuel charge is predicted, which results in increased volumetric flow and subsequent overfilling. The effect is validated with additional measurements.
High yields of hydrogen production from methanol steam reforming with a cross-U type reactor
Zhang, Shubin; Chen, Junyu; Zhang, Xuelin; Liu, Xiaowei
2017-01-01
This paper presents a numerical and experimental study on the performance of a methanol steam reformer integrated with a hydrogen/air combustion reactor for hydrogen production. A CFD-based 3D model with mass and momentum transport and temperature characteristics is established. The simulation results show that better performance is achieved in the cross-U type reactor compared to either a tubular reactor or a parallel-U type reactor because of more effective heat transfer characteristics. Furthermore, Cu-based micro reformers of both cross-U and parallel-U type reactors are designed, fabricated and tested for experimental validation. Under the same condition for reforming and combustion, the results demonstrate that higher methanol conversion is achievable in cross-U type reactor. However, it is also found in cross-U type reactor that methanol reforming selectivity is the lowest due to the decreased water gas shift reaction under high temperature, thereby carbon monoxide concentration is increased. Furthermore, the reformed gas generated from the reactors is fed into a high temperature proton exchange membrane fuel cell (PEMFC). In the test of discharging for 4 h, the fuel cell fed by cross-U type reactor exhibits the most stable performance. PMID:29121067
High yields of hydrogen production from methanol steam reforming with a cross-U type reactor.
Zhang, Shubin; Zhang, Yufeng; Chen, Junyu; Zhang, Xuelin; Liu, Xiaowei
2017-01-01
This paper presents a numerical and experimental study on the performance of a methanol steam reformer integrated with a hydrogen/air combustion reactor for hydrogen production. A CFD-based 3D model with mass and momentum transport and temperature characteristics is established. The simulation results show that better performance is achieved in the cross-U type reactor compared to either a tubular reactor or a parallel-U type reactor because of more effective heat transfer characteristics. Furthermore, Cu-based micro reformers of both cross-U and parallel-U type reactors are designed, fabricated and tested for experimental validation. Under the same condition for reforming and combustion, the results demonstrate that higher methanol conversion is achievable in cross-U type reactor. However, it is also found in cross-U type reactor that methanol reforming selectivity is the lowest due to the decreased water gas shift reaction under high temperature, thereby carbon monoxide concentration is increased. Furthermore, the reformed gas generated from the reactors is fed into a high temperature proton exchange membrane fuel cell (PEMFC). In the test of discharging for 4 h, the fuel cell fed by cross-U type reactor exhibits the most stable performance.
Cross Validation Through Two-Dimensional Solution Surface for Cost-Sensitive SVM.
Gu, Bin; Sheng, Victor S; Tay, Keng Yeow; Romano, Walter; Li, Shuo
2017-06-01
Model selection plays an important role in cost-sensitive SVM (CS-SVM). It has been proven that the global minimum cross validation (CV) error can be efficiently computed based on the solution path for one parameter learning problems. However, it is a challenge to obtain the global minimum CV error for CS-SVM based on one-dimensional solution path and traditional grid search, because CS-SVM is with two regularization parameters. In this paper, we propose a solution and error surfaces based CV approach (CV-SES). More specifically, we first compute a two-dimensional solution surface for CS-SVM based on a bi-parameter space partition algorithm, which can fit solutions of CS-SVM for all values of both regularization parameters. Then, we compute a two-dimensional validation error surface for each CV fold, which can fit validation errors of CS-SVM for all values of both regularization parameters. Finally, we obtain the CV error surface by superposing K validation error surfaces, which can find the global minimum CV error of CS-SVM. Experiments are conducted on seven datasets for cost sensitive learning and on four datasets for imbalanced learning. Experimental results not only show that our proposed CV-SES has a better generalization ability than CS-SVM with various hybrids between grid search and solution path methods, and than recent proposed cost-sensitive hinge loss SVM with three-dimensional grid search, but also show that CV-SES uses less running time.
Kalderstam, Jonas; Edén, Patrik; Ohlsson, Mattias
2015-01-01
We investigate a new method to place patients into risk groups in censored survival data. Properties such as median survival time, and end survival rate, are implicitly improved by optimizing the area under the survival curve. Artificial neural networks (ANN) are trained to either maximize or minimize this area using a genetic algorithm, and combined into an ensemble to predict one of low, intermediate, or high risk groups. Estimated patient risk can influence treatment choices, and is important for study stratification. A common approach is to sort the patients according to a prognostic index and then group them along the quartile limits. The Cox proportional hazards model (Cox) is one example of this approach. Another method of doing risk grouping is recursive partitioning (Rpart), which constructs a decision tree where each branch point maximizes the statistical separation between the groups. ANN, Cox, and Rpart are compared on five publicly available data sets with varying properties. Cross-validation, as well as separate test sets, are used to validate the models. Results on the test sets show comparable performance, except for the smallest data set where Rpart's predicted risk groups turn out to be inverted, an example of crossing survival curves. Cross-validation shows that all three models exhibit crossing of some survival curves on this small data set but that the ANN model manages the best separation of groups in terms of median survival time before such crossings. The conclusion is that optimizing the area under the survival curve is a viable approach to identify risk groups. Training ANNs to optimize this area combines two key strengths from both prognostic indices and Rpart. First, a desired minimum group size can be specified, as for a prognostic index. Second, the ability to utilize non-linear effects among the covariates, which Rpart is also able to do.
2014-01-01
Background As the diversity of the European population evolves, measuring providers’ skillfulness in cross-cultural care and understanding what contextual factors may influence this is increasingly necessary. Given limited information about differences in cultural competency by provider role, we compared cross-cultural skillfulness between physicians and nurses working at a Swiss university hospital. Methods A survey on cross-cultural care was mailed in November 2010 to front-line providers in Lausanne, Switzerland. This questionnaire included some questions from the previously validated Cross-Cultural Care Survey. We compared physicians’ and nurses’ mean composite scores and proportion of “3-good/4-very good” responses, for nine perceived skillfulness items (4-point Likert-scale) using the validated tool. We used linear regression to examine how provider role (physician vs. nurse) was associated with composite skillfulness scores, adjusting for demographics (gender, non-French dominant language), workplace (time at institution, work-unit “sensitized” to cultural-care), reported cultural-competence training, and cross-cultural care problem-awareness. Results Of 885 questionnaires, 368 (41.2%) returned the survey: 124 (33.6%) physicians and 244 (66.4%) nurses, reflecting institutional distribution of providers. Physicians had better mean composite scores for perceived skillfulness than nurses (2.7 vs. 2.5, p < 0.005), and significantly higher proportion of “good/very good” responses for 4/9 items. After adjusting for explanatory variables, physicians remained more likely to have higher skillfulness (β = 0.13, p = 0.05). Among all, higher skillfulness was associated with perception/awareness of problems in the following areas: inadequate cross-cultural training (β = 0.14, p = 0.01) and lack of practical experience caring for diverse populations (β = 0.11, p = 0.04). In stratified analyses among physicians alone, having French as a dominant language (β = −0.34, p < 0.005) was negatively correlated with skillfulness. Conclusions Overall, there is much room for cultural competency improvement among providers. These results support the need for cross-cultural skills training with an inter-professional focus on nurses, education that attunes provider awareness to the local issues in cross-cultural care, and increased diversity efforts in the work force, particularly among physicians. PMID:24479405
Scattering Cross Section of Sound Waves by the Modal Element Method
NASA Technical Reports Server (NTRS)
Baumeister, Kenneth J.; Kreider, Kevin L.
1994-01-01
#he modal element method has been employed to determine the scattered field from a plane acoustic wave impinging on a two dimensional body. In the modal element method, the scattering body is represented by finite elements, which are coupled to an eigenfunction expansion representing the acoustic pressure in the infinite computational domain surrounding the body. The present paper extends the previous work by developing the algorithm necessary to calculate the acoustics scattering cross section by the modal element method. The scattering cross section is the acoustical equivalent to the Radar Cross Section (RCS) in electromagnetic theory. Since the scattering cross section is evaluated at infinite distance from the body, an asymptotic approximation is used in conjunction with the standard modal element method. For validation, the scattering cross section of the rigid circular cylinder is computed for the frequency range 0.1 is less than or equal to ka is less than or equal to 100. Results show excellent agreement with the analytic solution.
Uchoa, Priscila Regina Candido Espinola; Bezerra, Thiago Freire Pinto; Lima, Élcio Duarte; Fornazieri, Marco Aurélio; Pinna, Fabio de Rezende; Sperandio, Fabiana de Araújo; Voegels, Richard Louis
The concept of quality of life is subjective and variable definition, which depends on the individual's perception of their state of health. Quality of life questionnaires are instruments designed to measure quality of life, but most are developed in a language other than Portuguese. Questionnaires can identify the most important symptoms, focus on consultation, and assist in defining the goals of treatment. Some of these have been validated for the Portuguese language, but none in children. To validate the translation with cross-cultural adaptation and validation of the Sinus and Nasal Quality of Life Survey (SN-5) into Portuguese. Prospective study of children aged 2-12 years with sinonasal symptoms of over 30 days. The study comprised two stages: (I) translation and cross-cultural adaptation of the SN-5 into Portuguese (SN-5p); and (II) validation of the SN5-p. Statistical analysis was performed to assess internal consistency, test-retest reliability, and sensitivity, as well as construct and discriminant validity and standardization. The SN-5 was translated and adapted into Portuguese (SN-5p) and the author of the original version approved the process. Validation was carried out by administration of the SN-5p to 51 pediatric patients with sinonasal complaints (mean age, 5.8±2.5 years; range, 2-12 years). The questionnaire exhibited adequate construct validity (0.62, p<0.01), internal consistency (Cronbach's alpha=0.73), and discriminant validity (p<0.01), as well as good test-retest reproducibility (Goodman-Kruskal gamma=0.957, p<0.001), good correlation with a visual analog scale (r=0.62, p<0.01), and sensitivity to change. This study reports the successful translation and cross-cultural adaptation of the SN-5 instrument into Brazilian Portuguese. The translated version exhibited adequate psychometric properties for assessment of disease-specific quality of life in pediatric patients with sinonasal complaints. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.
van Esch, Betty C A M; Gros-van Hest, Marjan; Westerbeek, Hans; Garssen, Johan
2013-03-27
A transglutaminase cross-linked caseinate was designed for use in dairy products to increase the viscosity of food matrices. The difference in structure of cross-linked caseinate might have implications for the risk of developing cow's milk allergy. The sensitizing capacity and the allergenicity (the potency to induce an allergic effector response) of cross-linked sodium caseinate was investigated using a mouse model for cow's milk allergy. Mice were orally sensitized with cross-linked caseinate or caseinate using cholera toxin as adjuvant. Anaphylactic shock reactions, change in body temperature, acute allergic skin response, caseinate-, cross-linked caseinate-IgE and mMCP-1 concentrations were determined after challenge with cross-linked caseinate or caseinate. Sensitization with cross-linked caseinate did not result in anaphylactic shock symptoms, drop in body temperature or release of serum mMCP-1. A tendency toward decreased casein-specific IgE levels was observed. The allergenicity did not differ between both products. These results indicate that in already caseinate-sensitized mice, cross-linked caseinate did not provoke more pronounced allergenic reactions compared to sodium caseinate. On top of that, reduced sensitization to cross-linked caseinate was observed. Cross-linked caseinate might therefore be an interesting new dietary concept for humans at risk for food allergy although more mechanistic studies and clinical trials are needed for validation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
ERIC Educational Resources Information Center
Schneider, W. Joel; Roman, Zachary
2018-01-01
We used data simulations to test whether composites consisting of cohesive subtest scores are more accurate than composites consisting of divergent subtest scores. We demonstrate that when multivariate normality holds, divergent and cohesive scores are equally accurate. Furthermore, excluding divergent scores results in biased estimates of…
Li, Yan; Andrade, Jorge
2017-01-01
A growing trend in the biomedical community is the use of Next Generation Sequencing (NGS) technologies in genomics research. The complexity of downstream differential expression (DE) analysis is however still challenging, as it requires sufficient computer programing and command-line knowledge. Furthermore, researchers often need to evaluate and visualize interactively the effect of using differential statistical and error models, assess the impact of selecting different parameters and cutoffs, and finally explore the overlapping consensus of cross-validated results obtained with different methods. This represents a bottleneck that slows down or impedes the adoption of NGS technologies in many labs. We developed DEApp, an interactive and dynamic web application for differential expression analysis of count based NGS data. This application enables models selection, parameter tuning, cross validation and visualization of results in a user-friendly interface. DEApp enables labs with no access to full time bioinformaticians to exploit the advantages of NGS applications in biomedical research. This application is freely available at https://yanli.shinyapps.io/DEAppand https://gallery.shinyapps.io/DEApp.
Agnihotri, Samira; Sundeep, P. V. D. S.; Seelamantula, Chandra Sekhar; Balakrishnan, Rohini
2014-01-01
Objective identification and description of mimicked calls is a primary component of any study on avian vocal mimicry but few studies have adopted a quantitative approach. We used spectral feature representations commonly used in human speech analysis in combination with various distance metrics to distinguish between mimicked and non-mimicked calls of the greater racket-tailed drongo, Dicrurus paradiseus and cross-validated the results with human assessment of spectral similarity. We found that the automated method and human subjects performed similarly in terms of the overall number of correct matches of mimicked calls to putative model calls. However, the two methods also misclassified different subsets of calls and we achieved a maximum accuracy of ninety five per cent only when we combined the results of both the methods. This study is the first to use Mel-frequency Cepstral Coefficients and Relative Spectral Amplitude - filtered Linear Predictive Coding coefficients to quantify vocal mimicry. Our findings also suggest that in spite of several advances in automated methods of song analysis, corresponding cross-validation by humans remains essential. PMID:24603717
Gunaydin, Gurkan; Citaker, Seyit; Meray, Jale; Cobanoglu, Gamze; Gunaydin, Ozge Ece; Hazar Kanik, Zeynep
2016-11-01
Validation of a self-report questionnaire. The purpose of this study was to investigate adaptation, validity, and reliability of the Turkish version of the Bournemouth Questionnaire. Low back pain is one of the most frequent disorders leading to activity limitation. This pain affects most of people in their lives. The most important point to evaluate patient's functional abilities and to decide a successful therapy procedure is to manage the assessment questionnaires precisely. One hundred ten patients with chronic low back pain were included in present study. To assess reliability, test-retest and internal consistency analyses were applied. The results of test-retest analysis were assessed by using Intraclass Correlation Coefficient method (95% confidence interval). For internal consistency, Cronbach alpha value was calculated. Validity of the questionnaire was assessed in terms of construct validity. For construct validity, factor analysis and convergent validity were tested. For convergent validity, total points of the Bournemouth Questionnaire were assessed with the total points of Quebec Back Pain Disability Scale and Roland Morris Disability Questionnaire by using Pearson correlation coefficient analysis. Cronbach alpha value was found 0.914, showing that this questionnaire has high internal consistency. The results of test-retest analysis were varying between 0.851 and 0.927, which shows that test-retest results are highly correlated. Factor analysis test indicated that this questionnaire had one factor. Pearson correlation coefficient of the Bournemouth Questionnaire with Roland Morris Disability Questionnaire was calculated 0.703 and it was found with Quebec Back Pain Disability Scale is 0.659. These results showed that the Bournemouth Questionnaire is very good correlated with Roland Morris Disability Questionnaire and Quebec Back Pain Disability Scale. The Turkish version of the Bournemouth Questionnaire is valid and reliable. 3.
Genomic selection in sugar beet breeding populations.
Würschum, Tobias; Reif, Jochen C; Kraft, Thomas; Janssen, Geert; Zhao, Yusheng
2013-09-18
Genomic selection exploits dense genome-wide marker data to predict breeding values. In this study we used a large sugar beet population of 924 lines representing different germplasm types present in breeding populations: unselected segregating families and diverse lines from more advanced stages of selection. All lines have been intensively phenotyped in multi-location field trials for six agronomically important traits and genotyped with 677 SNP markers. We used ridge regression best linear unbiased prediction in combination with fivefold cross-validation and obtained high prediction accuracies for all except one trait. In addition, we investigated whether a calibration developed based on a training population composed of diverse lines is suited to predict the phenotypic performance within families. Our results show that the prediction accuracy is lower than that obtained within the diverse set of lines, but comparable to that obtained by cross-validation within the respective families. The results presented in this study suggest that a training population derived from intensively phenotyped and genotyped diverse lines from a breeding program does hold potential to build up robust calibration models for genomic selection. Taken together, our results indicate that genomic selection is a valuable tool and can thus complement the genomics toolbox in sugar beet breeding.
Windhausen, Vanessa S.; Atlin, Gary N.; Hickey, John M.; Crossa, Jose; Jannink, Jean-Luc; Sorrells, Mark E.; Raman, Babu; Cairns, Jill E.; Tarekegne, Amsal; Semagn, Kassa; Beyene, Yoseph; Grudloyma, Pichet; Technow, Frank; Riedelsheimer, Christian; Melchinger, Albrecht E.
2012-01-01
Genomic prediction is expected to considerably increase genetic gains by increasing selection intensity and accelerating the breeding cycle. In this study, marker effects estimated in 255 diverse maize (Zea mays L.) hybrids were used to predict grain yield, anthesis date, and anthesis-silking interval within the diversity panel and testcross progenies of 30 F2-derived lines from each of five populations. Although up to 25% of the genetic variance could be explained by cross validation within the diversity panel, the prediction of testcross performance of F2-derived lines using marker effects estimated in the diversity panel was on average zero. Hybrids in the diversity panel could be grouped into eight breeding populations differing in mean performance. When performance was predicted separately for each breeding population on the basis of marker effects estimated in the other populations, predictive ability was low (i.e., 0.12 for grain yield). These results suggest that prediction resulted mostly from differences in mean performance of the breeding populations and less from the relationship between the training and validation sets or linkage disequilibrium with causal variants underlying the predicted traits. Potential uses for genomic prediction in maize hybrid breeding are discussed emphasizing the need of (1) a clear definition of the breeding scenario in which genomic prediction should be applied (i.e., prediction among or within populations), (2) a detailed analysis of the population structure before performing cross validation, and (3) larger training sets with strong genetic relationship to the validation set. PMID:23173094
Baumann, Soo Mee; Webb, Patrick; Zeller, Manfred
2013-03-01
Cross-cultural validity of food security indicators is commonly presumed without questioning the suitability of generic indicators in different geographic settings. However, ethnic differences in the perception of and reporting on, food insecurity, as well as variations in consumption patterns, may limit the comparability of results. Although research on correction factors for standardization of food security indicators is in process, so far no universal indicator has been identified. The current paper considers the ability of the Food Consumption Score (FCS) developed by the World Food Programme in southern Africa in 1996 to meet the requirement of local cultural validity in a Laotian context. The analysis is based on research that seeks to identify options for correcting possible biases linked to cultural disparities. Based on the results of a household survey conducted in different agroecological zones of Laos in 2009, the FCS was validated against a benchmark of calorie consumption. Changing the thresholds and excluding small amounts of food items consumed were tested as options to correct for biases caused by cultural disparities. The FCS in its original form underestimates the food insecurity level in the surveyed villages. However, the closeness of fit of the FCS to the benchmark classification improves when small amounts of food items are excluded from the assessment. Further research in different cultural settings is required to generate more insight into the extent to which universal thresholds can be applied to dietary diversity indicators with or without locally determined correction factors such as the exclusion of small amounts of food items.
Effects of Data Quality on the Characterization of Aerosol Properties from Multiple Sensors
NASA Technical Reports Server (NTRS)
Petrenko, Maksym; Ichoku, Charles; Leptoukh, Gregory
2011-01-01
Cross-comparison of aerosol properties between ground-based and spaceborne measurements is an important validation technique that helps to investigate the uncertainties of aerosol products acquired using spaceborne sensors. However, it has been shown that even minor differences in the cross-characterization procedure may significantly impact the results of such validation. Of particular consideration is the quality assurance I quality control (QA/QC) information - an auxiliary data indicating a "confidence" level (e.g., Bad, Fair, Good, Excellent, etc.) conferred by the retrieval algorithms on the produced data. Depending on the treatment of available QA/QC information, a cross-characterization procedure has the potential of filtering out invalid data points, such as uncertain or erroneous retrievals, which tend to reduce the credibility of such comparisons. However, under certain circumstances, even high QA/QC values may not fully guarantee the quality of the data. For example, retrievals in proximity of a cloud might be particularly perplexing for an aerosol retrieval algorithm, resulting in an invalid data that, nonetheless, could be assigned a high QA/QC confidence. In this presentation, we will study the effects of several QA/QC parameters on cross-characterization of aerosol properties between the data acquired by multiple spaceborne sensors. We will utilize the Multi-sensor Aerosol Products Sampling System (MAPSS) that provides a consistent platform for multi-sensor comparison, including collocation with measurements acquired by the ground-based Aerosol Robotic Network (AERONET), The multi-sensor spaceborne data analyzed include those acquired by the Terra-MODIS, Aqua-MODIS, Terra-MISR, Aura-OMI, Parasol-POLDER, and CalipsoCALIOP satellite instruments.
Evidence of Validity for the Japanese Version of the Foot and Ankle Ability Measure
Uematsu, Daisuke; Suzuki, Hidetomo; Sasaki, Shogo; Nagano, Yasuharu; Shinozuka, Nobuyuki; Sunagawa, Norihiko; Fukubayashi, Toru
2015-01-01
Context: The Foot and Ankle Ability Measure (FAAM) is a valid, reliable, and self-reported outcome instrument for the foot and ankle region. Objective: To provide evidence for translation, cross-cultural adaptation, validity, and reliability of the Japanese version of the FAAM (FAAM-J). Design: Cross-sectional study. Setting: Collegiate athletic training/sports medicine clinical setting. Patients or Other Participants: Eighty-three collegiate athletes. Main Outcome Measure(s): All participants completed the Activities of Daily Living and Sports subscales of the FAAM-J and the Physical Functioning and Mental Health subscales of the Japanese version of the Short Form-36v2 (SF-36). Also, 19 participants (23%) whose conditions were expected to be stable completed another FAAM-J 2 to 6 days later for test-retest reliability. We analyzed the scores of those subscales for convergent and divergent validity, internal consistency, and test-retest reliability. Results: The Activities of Daily Living and Sports subscales of the FAAM-J had correlation coefficients of 0.86 and 0.75, respectively, with the Physical Functioning section of the SF-36 for convergent validity. For divergent validity, the correlation coefficients with Mental Health of the SF-36 were 0.29 and 0.27 for each subscale, respectively. Cronbach α for internal consistency was 0.99 for the Activities of Daily Living and 0.98 for the Sports subscale. A 95% confidence interval with a single measure was ±8.1 and ±14.0 points for each subscale. The test-retest reliability measures revealed intraclass correlation coefficient values of 0.87 for the Activities of Daily Living and 0.91 for the Sports subscales with minimal detectable changes of ±6.8 and ±13.7 for the respective subscales. Conclusions: The FAAM was successfully translated for a Japanese version, and the FAAM-J was adapted cross-culturally. Thus, the FAAM-J can be used as a self-reported outcome measure for Japanese-speaking individuals; however, the scores must be interpreted with caution, especially when applied to different populations and other types of injury than those included in this study. PMID:25310247
Dragomir-Daescu, Dan; Buijs, Jorn Op Den; McEligot, Sean; Dai, Yifei; Entwistle, Rachel C.; Salas, Christina; Melton, L. Joseph; Bennet, Kevin E.; Khosla, Sundeep; Amin, Shreyasee
2013-01-01
Clinical implementation of quantitative computed tomography-based finite element analysis (QCT/FEA) of proximal femur stiffness and strength to assess the likelihood of proximal femur (hip) fractures requires a unified modeling procedure, consistency in predicting bone mechanical properties, and validation with realistic test data that represent typical hip fractures, specifically, a sideways fall on the hip. We, therefore, used two sets (n = 9, each) of cadaveric femora with bone densities varying from normal to osteoporotic to build, refine, and validate a new class of QCT/FEA models for hip fracture under loading conditions that simulate a sideways fall on the hip. Convergence requirements of finite element models of the first set of femora led to the creation of a new meshing strategy and a robust process to model proximal femur geometry and material properties from QCT images. We used a second set of femora to cross-validate the model parameters derived from the first set. Refined models were validated experimentally by fracturing femora using specially designed fixtures, load cells, and high speed video capture. CT image reconstructions of fractured femora were created to classify the fractures. The predicted stiffness (cross-validation R2 = 0.87), fracture load (cross-validation R2 = 0.85), and fracture patterns (83% agreement) correlated well with experimental data. PMID:21052839
Gambashidze, Nikoloz; Hammer, Antje; Brösterhaus, Mareen; Manser, Tanja
2017-11-09
To study the psychometric characteristics of German version of the Hospital Survey on Patient Safety Culture and to compare its dimensionality to other language versions in order to understand the instrument's potential for cross-national studies. Cross-sectional multicentre study to establish psychometric properties of German version of the survey instrument. 73 units from 37 departments of two German university hospitals. Clinical personnel (n=995 responses, response rate 39.6%). Psychometric properties (eg, model fit, internal consistency, construct validity) of the instrument and comparison of dimensionality across different language translations. The instrument demonstrated acceptable to good internal consistency (Cronbach's alpha 0.64-0.88). Confirmatory factor analysis of the original 12-factor model resulted in marginally satisfactory model fit (root mean square error of approximation (RMSEA)=0.05; standardised root mean residual (SRMR)=0.05; comparative fit index (CFI)=0.90; goodness of fit index (GFI)=0.88; Tucker-Lewis Index (TLI)=0.88). Exploratory factor analysis resulted in an alternative eight-factor model with good model fit (RMSEA=0.05; SRMR=0.05; CFI=0.95; GFI=0.91; TLI=0.94) and good internal consistency (Cronbach's alpha 0.73-0.87) and construct validity. Analysis of the dimensionality compared with models from 10 other language versions revealed eight dimensions with relatively stable composition and appearance across different versions and four dimensions requiring further improvement. The German version of Hospital Survey on Patient Safety Culture demonstrated satisfactory psychometric properties for use in German hospitals. However, our comparison of instrument dimensionality across different language versions indicates limitations concerning cross-national studies. Results of this study can be considered in interpreting findings across national contexts, in further refinement of the instrument for cross-national studies and in better understanding the various facets and dimensions of patient safety culture. © 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.
Radioactive Quality Evaluation and Cross Validation of Data from the HJ-1A/B Satellites' CCD Sensors
Zhang, Xin; Zhao, Xiang; Liu, Guodong; Kang, Qian; Wu, Donghai
2013-01-01
Data from multiple sensors are frequently used in Earth science to gain a more complete understanding of spatial information changes. Higher quality and mutual consistency are prerequisites when multiple sensors are jointly used. The HJ-1A/B satellites successfully launched on 6 September 2008. There are four charge-coupled device (CCD) sensors with uniform spatial resolutions and spectral range onboard the HJ-A/B satellites. Whether these data are keeping consistency is a major issue before they are used. This research aims to evaluate the data consistency and radioactive quality from the four CCDs. First, images of urban, desert, lake and ocean are chosen as the objects of evaluation. Second, objective evaluation variables, such as mean, variance and angular second moment, are used to identify image performance. Finally, a cross validation method are used to ensure the correlation of the data from the four HJ-1A/B CCDs and that which is gathered from the moderate resolution imaging spectro-radiometer (MODIS). The results show that the image quality of HJ-1A/B CCDs is stable, and the digital number distribution of CCD data is relatively low. In cross validation with MODIS, the root mean square errors of bands 1, 2 and 3 range from 0.055 to 0.065, and for band 4 it is 0.101. The data from HJ-1A/B CCD have better consistency. PMID:23881127
Zhang, Xin; Zhao, Xiang; Liu, Guodong; Kang, Qian; Wu, Donghai
2013-07-05
Data from multiple sensors are frequently used in Earth science to gain a more complete understanding of spatial information changes. Higher quality and mutual consistency are prerequisites when multiple sensors are jointly used. The HJ-1A/B satellites successfully launched on 6 September 2008. There are four charge-coupled device (CCD) sensors with uniform spatial resolutions and spectral range onboard the HJ-A/B satellites. Whether these data are keeping consistency is a major issue before they are used. This research aims to evaluate the data consistency and radioactive quality from the four CCDs. First, images of urban, desert, lake and ocean are chosen as the objects of evaluation. Second, objective evaluation variables, such as mean, variance and angular second moment, are used to identify image performance. Finally, a cross validation method are used to ensure the correlation of the data from the four HJ-1A/B CCDs and that which is gathered from the moderate resolution imaging spectro-radiometer (MODIS). The results show that the image quality of HJ-1A/B CCDs is stable, and the digital number distribution of CCD data is relatively low. In cross validation with MODIS, the root mean square errors of bands 1, 2 and 3 range from 0.055 to 0.065, and for band 4 it is 0.101. The data from HJ-1A/B CCD have better consistency.
Direct Validation of Differential Prediction.
ERIC Educational Resources Information Center
Lunneborg, Clifford E.
Using academic achievement data for 655 University students, direct validation of differential predictions based on a battery of aptitude/achievement measures selected for their differential prediction efficiency was attempted. In the cross-validation of the prediction of actual differences among five academic area GPA's, this set of differential…
A QSAR Model for Thyroperoxidase Inhibition and Screening ...
Thyroid hormones (THs) are critical modulators of a wide range of biological processes from neurodevelopment to metabolism. Well regulated levels of THs are critical during development and even moderate changes in maternal or fetal TH levels produce irreversible neurological deficits in children. The enzyme thyroperoxidase (TPO) plays a key role in the synthesis of THs. Inhibition of TPO by xenobiotics leads to decreased TH synthesis and, depending on the degree of synthesis inhibition, may result in adverse developmental outcomes. Recently, a high-throughput screening assay for TPO inhibition (AUR-TPO) was developed and used to screen the ToxCast Phase I and II chemicals. In the present study, we used the results from the AUR-TPO screening to develop a Quantitative Structure-Activity Relationship (QSAR) model for TPO inhibition in Leadscope®. The training set consisted of 898 discrete organic chemicals: 134 positive and 764 negative for TPO inhibition. A 10 times two-fold 50% cross-validation of the model was performed, yielding a balanced accuracy of 78.7% within its defined applicability domain. More recently, an additional ~800 chemicals from the US EPA Endocrine Disruption Screening Program (EDSP21) were screened using the AUR-TPO assay. This data was used for external validation of the QSAR model, demonstrating a balanced accuracy of 85.7% within its applicability domain. Overall, the cross- and external validations indicate a model with a high predictiv
Validation of TGLF in C-Mod and DIII-D using machine learning and integrated modeling tools
NASA Astrophysics Data System (ADS)
Rodriguez-Fernandez, P.; White, Ae; Cao, Nm; Creely, Aj; Greenwald, Mj; Grierson, Ba; Howard, Nt; Meneghini, O.; Petty, Cc; Rice, Je; Sciortino, F.; Yuan, X.
2017-10-01
Predictive models for steady-state and perturbative transport are necessary to support burning plasma operations. A combination of machine learning algorithms and integrated modeling tools is used to validate TGLF in C-Mod and DIII-D. First, a new code suite, VITALS, is used to compare SAT1 and SAT0 models in C-Mod. VITALS exploits machine learning and optimization algorithms for the validation of transport codes. Unlike SAT0, the SAT1 saturation rule contains a model to capture cross-scale turbulence coupling. Results show that SAT1 agrees better with experiments, further confirming that multi-scale effects are needed to model heat transport in C-Mod L-modes. VITALS will next be used to analyze past data from DIII-D: L-mode ``Shortfall'' plasma and ECH swing experiments. A second code suite, PRIMA, allows for integrated modeling of the plasma response to Laser Blow-Off cold pulses. Preliminary results show that SAT1 qualitatively reproduces the propagation of cold pulses after LBO injections and SAT0 does not, indicating that cross-scale coupling effects play a role in the plasma response. PRIMA will be used to ``predict-first'' cold pulse experiments using the new LBO system at DIII-D, and analyze existing ECH heat pulse data. Work supported by DE-FC02-99ER54512, DE-FC02-04ER54698.
Song, Jungeun; Leventhal, Bennett L.; Koh, Yun-Joo; Cheon, Keun-Ah; Hong, Hyun Ju; Kim, Young-Key; Cho, Kyungjin; Lim, Eun-Chung; Park, Jee In
2017-01-01
Purpose Our study aimed to examine psychometric properties and cross-cultural utility of the Behavior Assessment System for Children-2, Parent Rating Scale-Child (BASC-2 PRS-C) in Korean children. Materials and Methods Two study populations were recruited: a general population sample (n=2115) of 1st to 6th graders from 16 elementary schools and a clinical population (n=219) of 6–12 years old from 5 child psychiatric clinics and an epidemiological sample of autism spectrum disorder. We assessed the validity and reliability of the Korean version of BASC-2 PRS-C (K-BASC-2 PRS-C) and compared subscales with those used for US populations. Results Our results indicate that the K-BASC-2 PRS-C is a valuable instrument with reliability and validity for measuring developmental psychopathology that is comparable to those in Western population. However, there were some differences noted in the mean scores of BASC-2 PRS-C between Korean and US populations. Conclusion K-BASC-2 PRS-C is an effective and useful instrument with psychometric properties that permits measurement of general developmental psychopathology. Observed Korean-US differences in patterns of parental reports of children's behaviors indicate the importance of the validation, standardization and cultural adaptation for tools assessing psychopathology especially when used in populations different from those for which the instrument was originally created. PMID:28120577
Triaging Patient Complaints: Monte Carlo Cross-Validation of Six Machine Learning Classifiers
Cooper, William O; Catron, Thomas F; Karrass, Jan; Zhang, Zhe; Singh, Munindar P
2017-01-01
Background Unsolicited patient complaints can be a useful service recovery tool for health care organizations. Some patient complaints contain information that may necessitate further action on the part of the health care organization and/or the health care professional. Current approaches depend on the manual processing of patient complaints, which can be costly, slow, and challenging in terms of scalability. Objective The aim of this study was to evaluate automatic patient triage, which can potentially improve response time and provide much-needed scale, thereby enhancing opportunities to encourage physicians to self-regulate. Methods We implemented a comparison of several well-known machine learning classifiers to detect whether a complaint was associated with a physician or his/her medical practice. We compared these classifiers using a real-life dataset containing 14,335 patient complaints associated with 768 physicians that was extracted from patient complaints collected by the Patient Advocacy Reporting System developed at Vanderbilt University and associated institutions. We conducted a 10-splits Monte Carlo cross-validation to validate our results. Results We achieved an accuracy of 82% and F-score of 81% in correctly classifying patient complaints with sensitivity and specificity of 0.76 and 0.87, respectively. Conclusions We demonstrate that natural language processing methods based on modeling patient complaint text can be effective in identifying those patient complaints requiring physician action. PMID:28760726
Scanlan, Justin Newton; Hancock, Nicola; Honey, Anne
2018-03-01
There is a need for robust outcome measures for use in psychiatric services. Particularly lacking are self-rated recovery measures with evidence of sensitivity to change. This study was established to examine the convergent validity and sensitivity to change over time (responsiveness) of the Recovery Assessment Scale - Domains and Stages (RAS-DS), in comparison to level of unmet need as measured by the Camberwell Assessment of Need - Short Appraisal Scale (CANSAS). Convergent validity was examined through cross-sectional correlations between 540 CANSAS and RAS-DS scores collected on the same day for the same individuals. Sensitivity to change was examined using correlations between change scores in CANSAS and RAS-DS where both were collected on the same day and the two time points were separated by 90 days or more (n = 498). Results demonstrated moderate, significant cross-sectional correlations between CANSAS scores and RAS-DS total and domain scores and between change scores of both instruments. Results suggest that the RAS-DS is sensitive enough to detect change over time. Only moderate correlation between the RAS-DS and CANSAS suggests that, in the context of recovery-oriented service provision, it is important to measure self-reported recovery in addition to level of unmet needs. Copyright © 2018 Elsevier B.V. All rights reserved.
Quantitative studies on structure-DPPH• scavenging activity relationships of food phenolic acids.
Jing, Pu; Zhao, Shu-Juan; Jian, Wen-Jie; Qian, Bing-Jun; Dong, Ying; Pang, Jie
2012-11-01
Phenolic acids are potent antioxidants, yet the quantitative structure-activity relationships of phenolic acids remain unclear. The purpose of this study was to establish 3D-QSAR models able to predict phenolic acids with high DPPH• scavenging activity and understand their structure-activity relationships. The model has been established by using a training set of compounds with cross-validated q2 = 0.638/0.855, non-cross-validated r2 = 0.984/0.986, standard error of estimate = 0.236/0.216, and F = 139.126/208.320 for the best CoMFA/CoMSIA models. The predictive ability of the models was validated with the correlation coefficient r2(pred) = 0.971/0.996 (>0.6) for each model. Additionally, the contour map results suggested that structural characteristics of phenolics acids favorable for the high DPPH• scavenging activity might include: (1) bulky and/or electron-donating substituent groups on the phenol ring; (2) electron-donating groups at the meta-position and/or hydrophobic groups at the meta-/ortho-position; (3) hydrogen-bond donor/electron-donating groups at the ortho-position. The results have been confirmed based on structural analyses of phenolic acids and their DPPH• scavenging data from eight recent publications. The findings may provide deeper insight into the antioxidant mechanisms and provide useful information for selecting phenolic acids for free radical scavenging properties.
NASA Technical Reports Server (NTRS)
Hook, Simon J.
2008-01-01
The presentation includes an introduction, Lake Tahoe site layout and measurements, Salton Sea site layout and measurements, field instrument calibration and cross-calculations, data reduction methodology and error budgets, and example results for MODIS. Summary and conclusions are: 1) Lake Tahoe CA/NV automated validation site was established in 1999 to assess radiometric accuracy of satellite and airborne mid and thermal infrared data and products. Water surface temperatures range from 4-25C.2) Salton Sea CA automated validation site was established in 2008 to broaden range of available water surface temperatures and atmospheric water vapor test cases. Water surface temperatures range from 15-35C. 3) Sites provide all information necessary for validation every 2 mins (bulk temperature, skin temperature, air temperature, wind speed, wind direction, net radiation, relative humidity). 4) Sites have been used to validate mid and thermal infrared data and products from: ASTER, AATSR, ATSR2, MODIS-Terra, MODIS-Aqua, Landsat 5, Landsat 7, MTI, TES, MASTER, MAS. 5) Approximately 10 years of data available to help validate AVHRR.
Adams, James; Kruger, Uwe; Geis, Elizabeth; Gehn, Eva; Fimbres, Valeria; Pollard, Elena; Mitchell, Jessica; Ingram, Julie; Hellmers, Robert; Quig, David; Hahn, Juergen
2017-01-01
Introduction A number of previous studies examined a possible association of toxic metals and autism, and over half of those studies suggest that toxic metal levels are different in individuals with Autism Spectrum Disorders (ASD). Additionally, several studies found that those levels correlate with the severity of ASD. Methods In order to further investigate these points, this paper performs the most detailed statistical analysis to date of a data set in this field. First morning urine samples were collected from 67 children and adults with ASD and 50 neurotypical controls of similar age and gender. The samples were analyzed to determine the levels of 10 urinary toxic metals (UTM). Autism-related symptoms were assessed with eleven behavioral measures. Statistical analysis was used to distinguish participants on the ASD spectrum and neurotypical participants based upon the UTM data alone. The analysis also included examining the association of autism severity with toxic metal excretion data using linear and nonlinear analysis. “Leave-one-out” cross-validation was used to ensure statistical independence of results. Results and Discussion Average excretion levels of several toxic metals (lead, tin, thallium, antimony) were significantly higher in the ASD group. However, ASD classification using univariate statistics proved difficult due to large variability, but nonlinear multivariate statistical analysis significantly improved ASD classification with Type I/II errors of 15% and 18%, respectively. These results clearly indicate that the urinary toxic metal excretion profiles of participants in the ASD group were significantly different from those of the neurotypical participants. Similarly, nonlinear methods determined a significantly stronger association between the behavioral measures and toxic metal excretion. The association was strongest for the Aberrant Behavior Checklist (including subscales on Irritability, Stereotypy, Hyperactivity, and Inappropriate Speech), but significant associations were found for UTM with all eleven autism-related assessments with cross-validation R2 values ranging from 0.12–0.48. PMID:28068407
Measuring socioeconomic status in multicountry studies: results from the eight-country MAL-ED study
2014-01-01
Background There is no standardized approach to comparing socioeconomic status (SES) across multiple sites in epidemiological studies. This is particularly problematic when cross-country comparisons are of interest. We sought to develop a simple measure of SES that would perform well across diverse, resource-limited settings. Methods A cross-sectional study was conducted with 800 children aged 24 to 60 months across eight resource-limited settings. Parents were asked to respond to a household SES questionnaire, and the height of each child was measured. A statistical analysis was done in two phases. First, the best approach for selecting and weighting household assets as a proxy for wealth was identified. We compared four approaches to measuring wealth: maternal education, principal components analysis, Multidimensional Poverty Index, and a novel variable selection approach based on the use of random forests. Second, the selected wealth measure was combined with other relevant variables to form a more complete measure of household SES. We used child height-for-age Z-score (HAZ) as the outcome of interest. Results Mean age of study children was 41 months, 52% were boys, and 42% were stunted. Using cross-validation, we found that random forests yielded the lowest prediction error when selecting assets as a measure of household wealth. The final SES index included access to improved water and sanitation, eight selected assets, maternal education, and household income (the WAMI index). A 25% difference in the WAMI index was positively associated with a difference of 0.38 standard deviations in HAZ (95% CI 0.22 to 0.55). Conclusions Statistical learning methods such as random forests provide an alternative to principal components analysis in the development of SES scores. Results from this multicountry study demonstrate the validity of a simplified SES index. With further validation, this simplified index may provide a standard approach for SES adjustment across resource-limited settings. PMID:24656134
Cross-Cultural Validation of the Patient Perception of Integrated Care Survey.
Tietschert, Maike V; Angeli, Federica; van Raak, Arno J A; Ruwaard, Dirk; Singer, Sara J
2017-07-20
To test the cross-cultural validity of the U.S. Patient Perception of Integrated Care (PPIC) Survey in a Dutch sample using a standardized procedure. Primary data collected from patients of five primary care centers in the south of the Netherlands, through survey research from 2014 to 2015. Cross-sectional data collected from patients who saw multiple health care providers during 6 months preceding data collection. The PPIC survey includes 59 questions that measure patient perceived care integration across providers, settings, and time. Data analysis followed a standardized procedure guiding data preparation, psychometric analysis, and included invariance testing with the U.S. dataset. Latent scale structures of the Dutch and U.S. survey were highly comparable. Factor "Integration with specialist" had lower reliability scores and noninvariance. For the remaining factors, internal consistency and invariance estimates were strong. The standardized cross-cultural validation procedure produced strong support for comparable psychometric characteristics of the Dutch and U.S. surveys. Future research should examine the usability of the proposed procedure for contexts with greater cultural differences. © Health Research and Educational Trust.
Arnold, R; Ponnusamy, V; Zhang, C-Q; Gucciardi, D F
2017-08-01
Organizational stressors are a universal phenomenon which can be particularly prevalent and problematic for sport performers. In view of their global existence, it is surprising that no studies have examined cross-cultural differences in organizational stressors. One explanation for this is that the Organizational Stressor Indicator for Sport Performers (OSI-SP; Arnold, Fletcher, & Daniels, 2013), which can comprehensively measure the organizational pressures that sport performers have encountered, has not yet been translated from English into any other languages nor scrutinized cross-culturally. The first purpose of this study, therefore, was to examine the cross-cultural validity of the OSI-SP. In addition, the study aimed to test the equivalence of the OSI-SP's factor structure across cultures. British (n = 379), Chinese (n = 335), and Malaysian (n = 444) sport performers completed the OSI-SP. Confirmatory factor analyses confirmed the cross-cultural validity of the factorial model for the British and Malaysian samples; however, the overall model fit for the Chinese data did not meet all guideline values. Support was provided for the equality of factor loadings, variances, and covariances on the OSI-SP across the British and Malaysian cultures. These findings advance knowledge and understanding on the cross-cultural existence, conceptualization, and operationalization of organizational stressors. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Søndenaa, Erik; Nygård, Øyvind; Nøttestad, Jim Aage; Linaker, Olav Martin
2011-02-01
Intellectual disabilities (ID) among psychiatric patients have traditionally been neglected. A lack of convenient instruments and competency in ID may have worsened the conditions and treatment availability for these patients. Validation and adaptation of a screening instrument for ID (Hayes Ability Screening Index; HASI) in a psychiatric hospital setting. This is a cross-sectional study of 50 psychiatric patients in two Norwegian psychiatric hospitals comparing results of the HASI with the Wechsler Abbreviated Scale of Intelligence (WASI). The HASI correlated well with the standard IQ test used (r= 0.67, P< 0.001). At a stated cut-off score of 85, the HASI had a sensitivity of 100% and specificity of 34%. The HASI is a valid and time-saving screening instrument for ID among psychiatric patients. The prescribed cut-off score, however, resulted in a large number of false positives.
Cross-cultural validation of Irritable Bowel Syndrome Quality of Life in Korea.
Park, Jae M; Choi, Myung-Gyu; Oh, Jung Hwan; Cho, Yu Kyung; Lee, In Seok; Kim, Sang Woo; Choi, Kyu Yong; Chung, In-Sik
2006-08-01
Patients' responses to quality-of-life questionnaires are dependent on the cultural milieu. The aims of this study were to translate the Irritable Bowel Syndrome Quality of Life questionnaire, which was developed in the West, into Korean and to validate the translated questionnaire in patients with irritable bowel syndrome. Translation of the original questionnaire was performed according to accepted linguistic validation guidelines. Korean patients had no difficulty understanding the questions. Data from the translated questionnaire were well correlated with results from the SF-36 questionnaire and reflected the stress status of the patients as measured on the Perceived Stress Scale. Some questionnaire items seemed, on first analysis, to be problematic in this subset of patients, but these results may relate, in part, to cultural differences between Korea and the West. We conclude that the translated questionnaire is reliable and offers an accurate measure of quality of life for Korean patients with irritable bowel syndrome.
The Mt. Hood challenge: cross-testing two diabetes simulation models.
Brown, J B; Palmer, A J; Bisgaard, P; Chan, W; Pedula, K; Russell, A
2000-11-01
Starting from identical patients with type 2 diabetes, we compared the 20-year predictions of two computer simulation models, a 1998 version of the IMIB model and version 2.17 of the Global Diabetes Model (GDM). Primary measures of outcome were 20-year cumulative rates of: survival, first (incident) acute myocardial infarction (AMI), first stroke, proliferative diabetic retinopathy (PDR), macro-albuminuria (gross proteinuria, or GPR), and amputation. Standardized test patients were newly diagnosed males aged 45 or 75, with high and low levels of glycated hemoglobin (HbA(1c)), systolic blood pressure (SBP), and serum lipids. Both models generated realistic results and appropriate responses to changes in risk factors. Compared with the GDM, the IMIB model predicted much higher rates of mortality and AMI, and fewer strokes. These differences can be explained by differences in model architecture (Markov vs. microsimulation), different evidence bases for cardiovascular prediction (Framingham Heart Study cohort vs. Kaiser Permanente patients), and isolated versus interdependent prediction of cardiovascular events. Compared with IMIB, GDM predicted much higher lifetime costs, because of lower mortality and the use of a different costing method. It is feasible to cross-validate and explicate dissimilar diabetes simulation models using standardized patients. The wide differences in the model results that we observed demonstrate the need for cross-validation. We propose to hold a second 'Mt Hood Challenge' in 2001 and invite all diabetes modelers to attend.
Martin, Lelia Gonçalves Rocha; Gaidzinski, Raquel Rapone
2014-01-01
Objective Construct and to validate an instrument for measuring the time spent by nursing staff in the interventions/activities in Outpatient Oncology and Hematology, interventions based on Nursing Interventions Classification (NIC), for key areas of Pediatric Oncology and Oncology Nursing. Methods Cross-sectional study divided into two steps: (1) construction of an instrument to measure the interventions/Nursing activities and (2) validation of this instrument. Results We selected 32 essential interventions from NIC for Pediatric Oncology and Oncology Nursing areas. The judges agreed with removing 13 and including 6 interventions in the instrument, beyond personal activity. Conclusion The choice of essential interventions from NIC is justified by the gain time on research. PMID:25295454
Three-factor structure for Epistemic Belief Inventory: A cross-validation study
2017-01-01
Research on epistemic beliefs has been hampered by lack of validated models and measurement instruments. The most widely used instrument is the Epistemological Questionnaire, which has been criticized for validity, and it has been proposed a new instrument based in the Epistemological Questionnaire: the Epistemic Belief Inventory. The Spanish-language version of Epistemic Belief Inventory was applied to 1,785 Chilean high school students. Exploratory and confirmatory factor analyses in independent subsamples were performed. A three factor structure emerged and was confirmed. Reliability was comparable to other studies, and the factor structure was invariant among randomized subsamples. The structure that was found does not replicate the one proposed originally, but results are interpreted in light of embedded systemic model of epistemological beliefs. PMID:28278258
Moreno-Murcia, Juan A; Martínez-Galindo, Celestina; Moreno-Pérez, Víctor; Marcos, Pablo J.; Borges, Fernanda
2012-01-01
This study aimed to cross-validate the psychometric properties of the Basic Psychological Needs in Exercise Scale (BPNES) by Vlachopoulos and Michailidou, 2006 in a Spanish context. Two studies were conducted. Confirmatory factor analysis results confirmed the hypothesized three-factor solution In addition, we documented evidence of reliability, analysed as internal consistency and temporal stability. Future studies should analyse the scale's validity and reliability with different populations and check their experimental effect. Key pointsThe Basic Psychological Needs in Exercise Scale (BPNES) is valid and reliable for measuring basic psychological needs in healthy physical exercise in the Spanish context.The factor structure of three correlated factors has shown minimal invariance across gender. PMID:24149130
Naghdi, Soofia; Ansari, Noureddin Nakhostin; Raji, Parvin; Shamili, Aryan; Amini, Malek; Hasson, Scott
2016-01-01
To translate and cross-culturally adapt the Functional Independence Measure (FIM) into the Persian language and to test the reliability and validity of the Persian FIM (PFIM) in patients with stroke. In this cross-sectional study carried out in an outpatient stroke rehabilitation center, 40 patients with stroke (mean age 60 years) were participated. A standard forward-backward translation method and expert panel validation was followed to develop the PFIM. Two experienced occupational therapists (OTs) assessed the patients independently in all items of the PFIM in a single session for inter-rater reliability. One of the OTs reassessed the patients after 1 week for intra-rater reliability. There were no floor or ceiling effects for the PFIM. Excellent inter-rater and intra-rater reliability was noted for the PFIM total score, motor and cognitive subscales (ICC(agreement)0.88-0.98). According to the Bland-Altman agreement analysis, there was no systematic bias between raters and within raters. The internal consistency of the PFIM was with Cronbach's alpha from 0.70 to 0.96. The principal component analysis with varimax rotation indicated a three-factor structure: (1) self-care and mobility; (2) sphincter control and (3) cognitive that jointly accounted for 74.8% of the total variance. Construct validity was supported by a significant Pearson correlation between the PFIM and the Persian Barthel Index (r = 0.95; p < 0.001). The PFIM is a highly reliable and valid instrument for measuring functional status of Persian patients with stroke. The Functional Independence Measure (FIM) is an outcome measure for disability based on the International Classification of Functioning, Disability and Health (ICF). The FIM was cross-culturally adapted and validated into Persian language. The Persian version of the FIM (PFIM) is reliable and valid for assessing functional status of patients with stroke. The PFIM can be used in Persian speaking countries to assess the limitations in activities of daily living of patients with stroke.
Goel, Honey; Sinha, V R; Thareja, Suresh; Aggarwal, Saurabh; Kumar, Manoj
2011-08-30
The quinolones belong to a family of synthetic potent broad-spectrum antibiotics and particularly active against gram-negative organisms, especially Pseudomonas aeruginosa. A 3D-QSPkR approach has been used to obtain the quantitative structure pharmacokinetic relationship for a series of quinolone drugs using SOMFA. The series consisting of 28 molecules have been investigated for their pharmacokinetic performance using biological half life (t(1/2)). A statistically validated robust model for a diverse group of quinolone drugs having flexibility in structure and pharmacokinetic profile (t(1/2)) obtained using SOMFA having good cross-validated correlation coefficient r(cv)(2) (0.6847), non cross-validated correlation coefficient r(2) values (0.7310) and high F-test value (33.9663). Analysis of 3D-QSPkR models through electrostatic and shape grids provide useful information about the shape and electrostatic potential contributions on t(1/2). The analysis of SOMFA results provide an insight for the generation of novel molecular architecture of quinolones with optimal half life and improved biological profile. Copyright © 2011 Elsevier B.V. All rights reserved.
Cheng, Feixiong; Shen, Jie; Yu, Yue; Li, Weihua; Liu, Guixia; Lee, Philip W; Tang, Yun
2011-03-01
There is an increasing need for the rapid safety assessment of chemicals by both industries and regulatory agencies throughout the world. In silico techniques are practical alternatives in the environmental hazard assessment. It is especially true to address the persistence, bioaccumulative and toxicity potentials of organic chemicals. Tetrahymena pyriformis toxicity is often used as a toxic endpoint. In this study, 1571 diverse unique chemicals were collected from the literature and composed of the largest diverse data set for T. pyriformis toxicity. Classification predictive models of T. pyriformis toxicity were developed by substructure pattern recognition and different machine learning methods, including support vector machine (SVM), C4.5 decision tree, k-nearest neighbors and random forest. The results of a 5-fold cross-validation showed that the SVM method performed better than other algorithms. The overall predictive accuracies of the SVM classification model with radial basis functions kernel was 92.2% for the 5-fold cross-validation and 92.6% for the external validation set, respectively. Furthermore, several representative substructure patterns for characterizing T. pyriformis toxicity were also identified via the information gain analysis methods. Copyright © 2010 Elsevier Ltd. All rights reserved.
Approximate l-fold cross-validation with Least Squares SVM and Kernel Ridge Regression
DOE Office of Scientific and Technical Information (OSTI.GOV)
Edwards, Richard E; Zhang, Hao; Parker, Lynne Edwards
2013-01-01
Kernel methods have difficulties scaling to large modern data sets. The scalability issues are based on computational and memory requirements for working with a large matrix. These requirements have been addressed over the years by using low-rank kernel approximations or by improving the solvers scalability. However, Least Squares Support VectorMachines (LS-SVM), a popular SVM variant, and Kernel Ridge Regression still have several scalability issues. In particular, the O(n^3) computational complexity for solving a single model, and the overall computational complexity associated with tuning hyperparameters are still major problems. We address these problems by introducing an O(n log n) approximate l-foldmore » cross-validation method that uses a multi-level circulant matrix to approximate the kernel. In addition, we prove our algorithm s computational complexity and present empirical runtimes on data sets with approximately 1 million data points. We also validate our approximate method s effectiveness at selecting hyperparameters on real world and standard benchmark data sets. Lastly, we provide experimental results on using a multi-level circulant kernel approximation to solve LS-SVM problems with hyperparameters selected using our method.« less
Vijayaraj, Ramadoss; Devi, Mekapothula Lakshmi Vasavi; Subramanian, Venkatesan; Chattaraj, Pratim Kumar
2012-06-01
Three-dimensional quantitative structure activity relationship (3D-QSAR) study has been carried out on the Escherichia coli DHFR inhibitors 2,4-diamino-5-(substituted-benzyl)pyrimidine derivatives to understand the structural features responsible for the improved potency. To construct highly predictive 3D-QSAR models, comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods were used. The predicted models show statistically significant cross-validated and non-cross-validated correlation coefficient of r2 CV and r2 nCV, respectively. The final 3D-QSAR models were validated using structurally diverse test set compounds. Analysis of the contour maps generated from CoMFA and CoMSIA methods reveals that the substitution of electronegative groups at the first and second position along with electropositive group at the third position of R2 substitution significantly increases the potency of the derivatives. The results obtained from the CoMFA and CoMSIA study delineate the substituents on the trimethoprim analogues responsible for the enhanced potency and also provide valuable directions for the design of new trimethoprim analogues with improved affinity. © 2012 John Wiley & Sons A/S.
ERIC Educational Resources Information Center
Dumka, Larry E.; And Others
1996-01-01
Discusses initial validation and evaluation of the cross-cultural and cross-language equivalence of the Parenting Self-Agency Measure (PSAM) with English-speaking middle-income Anglo mothers (n=90) and Spanish-speaking low-income Mexican immigrant mothers (n=94). Hypothesized relationship of PSAM with measures of parents' coping strategies and…
Gülgöz, S
2001-01-01
The cross-cultural validity of the Need for Cognition Scale and its relationship with cognitive performance were investigated in two studies. In the first study, the relationships between the scale and university entrance scores, course grades, study skills, and social desirability were examined. Using the short form of the Turkish version of the Need for Cognition Scale (S. Gülöz & C. J. Sadowski, 1995) no correlation with academic performance was found but there was significant correlation with a study skills scale and a social desirability scale created for this study. When regression analysis was used to predict grade point average, the Need for Cognition Scale was a significant predictor. In the second study, participants low or high in need for cognition solved multiple-solution anagrams. The instructions preceding the task set the participants' expectations regarding task difficulty. An interaction between expectation and need for cognition indicated that participants with low need for cognition performed worse when they expected difficult problems. Results of the two studies showed that need for cognition has cross-cultural validity and that its effect on cognitive performance was mediated by other variables.
Diagnostic Crossover in Anorexia Nervosa and Bulimia Nervosa: Implications for DSM-V
Eddy, Kamryn T.; Dorer, David J.; Franko, Debra L.; Tahilani, Kavita; Thompson-Brenner, Heather; Herzog, David B.
2011-01-01
Objective The Diagnostic and Statistical Manual of Mental Disorders (DSM) is designed primarily as a clinical tool. Yet high rates of diagnostic “crossover” among the anorexia nervosa subtypes and bulimia nervosa may reflect problems with the validity of the current diagnostic schema, thereby limiting its clinical utility. This study was designed to examine diagnostic crossover longitudinally in anorexia nervosa and bulimia nervosa to inform the validity of the DSM-IV-TR eating disorders classification system. Method A total of 216 women with a diagnosis of anorexia nervosa or bulimia nervosa were followed for 7 years; weekly eating disorder symptom data collected using the Eating Disorder Longitudinal Interval Follow-Up Examination allowed for diagnoses to be made throughout the follow-up period. Results Over 7 years, the majority of women with anorexia nervosa experienced diagnostic crossover: more than half crossed between the restricting and binge eating/purging anorexia nervosa subtypes over time; one-third crossed over to bulimia nervosa but were likely to relapse into anorexia nervosa. Women with bulimia nervosa were unlikely to cross over to anorexia nervosa. Conclusions These findings support the longitudinal distinction of anorexia nervosa and bulimia nervosa but do not support the anorexia nervosa subtyping schema. PMID:18198267
Cognitive—Motor Interference in an Ecologically Valid Street Crossing Scenario
Janouch, Christin; Drescher, Uwe; Wechsler, Konstantin; Haeger, Mathias; Bock, Otmar; Voelcker-Rehage, Claudia
2018-01-01
Laboratory-based research revealed that gait involves higher cognitive processes, leading to performance impairments when executed with a concurrent loading task. Deficits are especially pronounced in older adults. Theoretical approaches like the multiple resource model highlight the role of task similarity and associated attention distribution problems. It has been shown that in cases where these distribution problems are perceived relevant to participant's risk of falls, older adults prioritize gait and posture over the concurrent loading task. Here we investigate whether findings on task similarity and task prioritization can be transferred to an ecologically valid scenario. Sixty-three younger adults (20–30 years of age) and 61 older adults (65–75 years of age) participated in a virtual street crossing simulation. The participants' task was to identify suitable gaps that would allow them to cross a simulated two way street safely. Therefore, participants walked on a manual treadmill that transferred their forward motion to forward displacements in a virtual city. The task was presented as a single task (crossing only) and as a multitask. In the multitask condition participants were asked, among others, to type in three digit numbers that were presented either visually or auditorily. We found that for both age groups, street crossing as well as typing performance suffered under multitasking conditions. Impairments were especially pronounced for older adults (e.g., longer crossing initiation phase, more missed opportunities). However, younger and older adults did not differ in the speed and success rate of crossing. Further, deficits were stronger in the visual compared to the auditory task modality for most parameters. Our findings conform to earlier studies that found an age-related decline in multitasking performance in less realistic scenarios. However, task similarity effects were inconsistent and question the validity of the multiple resource model within ecologically valid scenarios. PMID:29774001
2D data-space cross-gradient joint inversion of MT, gravity and magnetic data
NASA Astrophysics Data System (ADS)
Pak, Yong-Chol; Li, Tonglin; Kim, Gang-Sop
2017-08-01
We have developed a data-space multiple cross-gradient joint inversion algorithm, and validated it through synthetic tests and applied it to magnetotelluric (MT), gravity and magnetic datasets acquired along a 95 km profile in Benxi-Ji'an area of northeastern China. To begin, we discuss a generalized cross-gradient joint inversion for multiple datasets and model parameters sets, and formulate it in data space. The Lagrange multiplier required for the structural coupling in the data-space method is determined using an iterative solver to avoid calculation of the inverse matrix in solving the large system of equations. Next, using model-space and data-space methods, we inverted the synthetic data and field data. Based on our result, the joint inversion in data-space not only delineates geological bodies more clearly than the separate inversion, but also yields nearly equal results with the one in model-space while consuming much less memory.
A diagnostic technique used to obtain cross range radiation centers from antenna patterns
NASA Technical Reports Server (NTRS)
Lee, T. H.; Burnside, W. D.
1988-01-01
A diagnostic technique to obtain cross range radiation centers based on antenna radiation patterns is presented. This method is similar to the synthetic aperture processing of scattered fields in the radar application. Coherent processing of the radiated fields is used to determine the various radiation centers associated with the far-zone pattern of an antenna for a given radiation direction. This technique can be used to identify an unexpected radiation center that creates an undesired effect in a pattern; on the other hand, it can improve a numerical simulation of the pattern by identifying other significant mechanisms. Cross range results for two 8' reflector antennas are presented to illustrate as well as validate that technique.
The Kings Cross fire: psychological reactions.
Turner, S W; Thompson, J; Rosser, R M
1995-07-01
The psychological reactions of 50 survivors of the King's Cross fire, which hit London's underground railway system on the 18th day of November 1987, are described. Results are presented for the Impact of Event scale, the General Health Questionnaire (28-item version), the Eysenck Personality Questionnaire and a King's Cross Event Schedule. These are investigated in relation to (a) validity measures, (b) relationships between exposure and personality, and (c) spontaneous de-briefing. Two thirds of the sample had significant levels of psychological distress (meeting the "caseness" criterion on the GHQ). Both personality (neuroticism and L-scale) and degree of trauma exposure were related to subsequent reaction. Spontaneous debriefing was associated with subjective benefit. Transportation disasters present particular problems in relation to research and service delivery.
Novel Screening Tool for Stroke Using Artificial Neural Network.
Abedi, Vida; Goyal, Nitin; Tsivgoulis, Georgios; Hosseinichimeh, Niyousha; Hontecillas, Raquel; Bassaganya-Riera, Josep; Elijovich, Lucas; Metter, Jeffrey E; Alexandrov, Anne W; Liebeskind, David S; Alexandrov, Andrei V; Zand, Ramin
2017-06-01
The timely diagnosis of stroke at the initial examination is extremely important given the disease morbidity and narrow time window for intervention. The goal of this study was to develop a supervised learning method to recognize acute cerebral ischemia (ACI) and differentiate that from stroke mimics in an emergency setting. Consecutive patients presenting to the emergency department with stroke-like symptoms, within 4.5 hours of symptoms onset, in 2 tertiary care stroke centers were randomized for inclusion in the model. We developed an artificial neural network (ANN) model. The learning algorithm was based on backpropagation. To validate the model, we used a 10-fold cross-validation method. A total of 260 patients (equal number of stroke mimics and ACIs) were enrolled for the development and validation of our ANN model. Our analysis indicated that the average sensitivity and specificity of ANN for the diagnosis of ACI based on the 10-fold cross-validation analysis was 80.0% (95% confidence interval, 71.8-86.3) and 86.2% (95% confidence interval, 78.7-91.4), respectively. The median precision of ANN for the diagnosis of ACI was 92% (95% confidence interval, 88.7-95.3). Our results show that ANN can be an effective tool for the recognition of ACI and differentiation of ACI from stroke mimics at the initial examination. © 2017 American Heart Association, Inc.
Mendonça, Bianca; Sargent, Barbara; Fetters, Linda
2016-12-01
To investigate whether standardized motor development screening and assessment tools that are used to evaluate motor abilities of children aged 0 to 2 years are valid in cultures other than those in which the normative sample was established. This was a systematic review in which six databases were searched. Studies were selected based on inclusion/exclusion criteria and appraised for evidence level and quality. Study variables were extracted. Twenty-three studies representing six motor development screening and assessment tools in 16 cultural contexts met the inclusion criteria: Alberta Infant Motor Scale (n=7), Ages and Stages Questionnaire, 3rd edition (n=2), Bayley Scales of Infant and Toddler Development, 3rd edition (n=8), Denver Developmental Screening Test, 2nd edition (n=4), Harris Infant Neuromotor Test (n=1), and Peabody Developmental Motor Scales, 2nd edition (n=1). Thirteen studies found significant differences between the cultural context and normative sample. Two studies established reliability and/or validity of standardized motor development assessments in high-risk infants from different cultural contexts. Five studies established new population norms. Eight studies described the cross-cultural adaptation of a standardized motor development assessment. Standardized motor development assessments have limited validity in cultures other than that in which the normative sample was established. Their use can result in under- or over-referral for services. © 2016 Mac Keith Press.
de Sousa, Carla Suellen Pires; Castro, Régia Christina Moura Barbosa; Pinheiro, Ana Karina Bezerra; Moura, Escolástica Rejane Ferreira; Almeida, Paulo César; Aquino, Priscila de Souza
2018-01-01
ABSTRACT Objective: translate and adapt the Condom Self-Efficacy Scale to Portuguese in the Brazilian context. The scale originated in the United States and measures self-efficacy in condom use. Method: methodological study in two phases: translation, cross-cultural adaptation and verification of psychometric properties. The translation and adaptation process involved four translators, one mediator of the synthesis and five health professionals. The content validity was verified using the Content Validation Index, based on 22 experts’ judgments. Forty subjects participated in the pretest, who contributed to the understanding of the scale items. The scale was applied to 209 students between 13 and 26 years of age from a school affiliated with the state-owned educational network. The reliability was analyzed by means of Cronbach’s alpha. Results: the Portuguese version of the scale obtained a Cronbach’s alpha coefficient of 0.85 and the total mean score was 68.1 points. A statistically significant relation was found between the total scale and the variables not having children (p= 0.038), condom use (p= 0.008) and condom use with fixed partner (p=0.036). Conclusion: the Brazilian version of the Condom Self-Efficacy Scale is a valid and reliable tool to verify the self-efficacy in condom use among adolescents and young adults. PMID:29319748
PIV Measurements of the CEV Hot Abort Motor Plume for CFD Validation
NASA Technical Reports Server (NTRS)
Wernet, Mark; Wolter, John D.; Locke, Randy; Wroblewski, Adam; Childs, Robert; Nelson, Andrea
2010-01-01
NASA s next manned launch platform for missions to the moon and Mars are the Orion and Ares systems. Many critical aspects of the launch system performance are being verified using computational fluid dynamics (CFD) predictions. The Orion Launch Abort Vehicle (LAV) consists of a tower mounted tractor rocket tasked with carrying the Crew Module (CM) safely away from the launch vehicle in the event of a catastrophic failure during the vehicle s ascent. Some of the predictions involving the launch abort system flow fields produced conflicting results, which required further investigation through ground test experiments. Ground tests were performed to acquire data from a hot supersonic jet in cross-flow for the purpose of validating CFD turbulence modeling relevant to the Orion Launch Abort Vehicle (LAV). Both 2-component axial plane Particle Image Velocimetry (PIV) and 3-component cross-stream Stereo Particle Image Velocimetry (SPIV) measurements were obtained on a model of an Abort Motor (AM). Actual flight conditions could not be simulated on the ground, so the highest temperature and pressure conditions that could be safely used in the test facility (nozzle pressure ratio 28.5 and a nozzle temperature ratio of 3) were used for the validation tests. These conditions are significantly different from those of the flight vehicle, but were sufficiently high enough to begin addressing turbulence modeling issues that predicated the need for the validation tests.
HA, Mei; QIAN, Xiaoling; YANG, Hong; HUANG, Jichun; LIU, Changjiang
2016-01-01
Background: The public’s cognition of stroke and responses to stroke symptoms are important to prevent complications and decrease the mortality when stroke occurs. The aim of study was to develop and validate the Chinese version of the Stroke Action Test (C-STAT) in a Chinese population. Methods: This study was rigorously implemented with the published guideline for the translation, adaptation and validation of instruments for the cross-cultural use in healthcare care research. A cross-sectional study was performed among 328 stroke patients and family members in the Department of Neurology in the Second Hospital of Lanzhou University, Gansu province, China in 2014. Results: The Chinese version of the instrument showed favorable content equivalence with the source version. Values of Cronbach’s alpha and test-retest reliability of the C-STAT were 0.88 and 0.86, respectively. Principal component analysis supported four-factor solutions of the C-STAT. Criterion-related validity showed that the C-STAT was a significant predictor of the 7-item stroke symptom scores (R = 0.77; t = 21.74, P< 0.001). Conclusion: The C-STAT is an intelligible and brief psychometrical tool to assess individuals’ knowledge of the appropriate responses to stroke symptoms in Chinese populations. It could also be used by health care providers to assess educational programs on stroke prevention. PMID:28053925
Gould, Gillian Sandra; Watt, Kerrianne; Cadet-James, Yvonne; Clough, Alan R.
2014-01-01
Objective To validate, for the first time, the Risk Behaviour Diagnosis (RBD) Scale for Aboriginal Australian tobacco smokers, based on the Extended Parallel Process Model (EPPM). Despite high smoking prevalence, little is known about how Indigenous peoples assess their smoking risks. Methods In a cross-sectional study of 121 aboriginal smokers aged 18–45 in regional New South Wales, in 2014, RBD subscales were assessed for internal consistency. Scales included measures of perceived threat (susceptibility to and severity of smoking risks) and perceived efficacy (response efficacy and self-efficacy for quitting). An Aboriginal community panel appraised face and content validity. EPPM constructs of danger control (protective motivation) and fear control (defensive motivation) were assessed for cogency. Results Scales had acceptable to good internal consistency (Cronbach's alpha = 0.65–1.0). Most participants demonstrated high-perceived threat (77%, n = 93); and half had high-perceived efficacy (52%, n = 63). High-perceived efficacy with high-threat appeared consistent with danger control dominance; low-perceived efficacy with high-threat was consistent with fear control dominance. Conclusions In these Aboriginal smokers of reproductive age, the RBD Scale appeared valid and reliable. Further research is required to assess whether the RBD Scale and EPPM can predict quit attempts and assist with tailored approaches to counselling and targeted health promotion campaigns. PMID:26844043
Reliability and validity of functional performance tests in dancers with hip dysfunction.
Kivlan, Benjamin R; Carcia, Christopher R; Clemente, F Richard; Phelps, Amy L; Martin, Robroy L
2013-08-01
Quasi-experimental, repeated measures. Functional performance tests that identify hip joint impairments and assess the effect of intervention have not been adequately described for dancers. The purpose of this study was to examine the reliability and validity of hop and balance tests among a group of dancers with musculoskeletal pain in the hip region. NINETEEN FEMALE DANCERS (AGE: 18.90±1.11 years; height: 164.85±6.95 cm; weight: 60.37±8.29 kg) with unilateral hip pain were assessed utilizing the cross-over reach, medial triple hop, lateral triple hop, and cross-over hop tests on two occasions, 2 days apart. Test-retest reliability and comparisons between the involved and uninvolved side for each respective test were determined. Intra-class correlation coefficients for the functional performance tests ranged from 0.89-0.96. The cross-over reach test had a SEM of 2.79 cm and a MDC of 7.73 cm. The medial and lateral triple hop tests had SEM values of 7.51 cm and 8.17 cm, and MDC values of 20.81 cm and 22.62 cm, respectively. The SEM was 0.15 seconds and the MDC was 0.42 seconds for the cross-over hop test. Performance on the medial triple hop test was significantly less on the involved side (370.21±38.26 cm) compared to the uninvolved side (388.05±41.49 cm); t(18) = -4.33, p<0.01. The side-to-side comparisons of the cross-over reach test (involved mean=61.68±10.9 cm; uninvolved mean=61.69±8.63 cm); t(18) = -0.004, p=0.99, lateral triple hop test (involved mean=306.92±35.79 cm; uninvolved mean=310.68±24.49 cm); t(18) = -0.55, p=0.59, and cross-over hop test (involved mean=2.49±0.34 seconds; uninvolved mean= 2.61±0.42 seconds; t(18) = -1.84, p=0.08) were not statistically different between sides. The functional performance tests used in this study can be reliably performed on dancers with unilateral hip pain. The medial triple hop test was the only functional performance test with evidence of validity in side-to-side comparisons. These results suggest that the medial triple hop test may be a reliable and valid functional performance test to assess impairments related to hip pain among dancers. 3b. Non-consecutive cohort study.
Basis Selection for Wavelet Regression
NASA Technical Reports Server (NTRS)
Wheeler, Kevin R.; Lau, Sonie (Technical Monitor)
1998-01-01
A wavelet basis selection procedure is presented for wavelet regression. Both the basis and the threshold are selected using cross-validation. The method includes the capability of incorporating prior knowledge on the smoothness (or shape of the basis functions) into the basis selection procedure. The results of the method are demonstrated on sampled functions widely used in the wavelet regression literature. The results of the method are contrasted with other published methods.
San Alberto Giraldos, Mercedes; López Leiva, Inmaculada; León Campos, Álvaro; Martí García, Celia; García Mayor, Silvia
2018-01-01
Aims To adapt the Edinburgh Feeding Evaluation in Dementia Scale (EdFED) for use in a Spanish-speaking population and to assess its validity and reliability in patients with dementia. Method A cross-sectional study was carried out in two stages: 1. Cross-cultural adaptation (translation, back-translation, review by committee of experts, pilot test and weighting of results); 2. Clinimetric validation comprising interobserver reliability assessment, test-retest reliability and internal consistency. To determine construct validity, confirmatory factorial analysis and principal components analysis were performed by oblique rotations. Criteria validity was analysed using the Pearson correlation (p<0.05) with the BMI, MNA and analytical values of albumin, transferrin, cholesterol, absolute lymphocytes and total proteins. Data collection was carried out for six months in 2016 in nursing homes and Alzheimer’s day centers in the province of Málaga (Spain), at nine centers, with 262 patients (aged over 60 years and presenting feeding difficulties), 20 nurses, 20 professional caregivers and 103 family caregivers. Results A version of EdFED culturally adapted to Spanish was obtained. The sample presented the following characteristics: 76.3% women, mean age 82.3 years (SD: 7.9); MNA 18.73 (SD: 4.44); BMI 23.99 (SD: 4.72); serum albumin 3.79 mg/dl (SD: 0.36). A Cronbach’s alpha of 0.88 was obtained, with an inter-item global correlation of 0.43 and a homogeneity index ranging from 0.42 to 0.73. The exploratory factor analysis reproduced the three-factor model identified by the original authors, explaining 62.32% of the total variance. The criterion validity showed a good inverse correlation with MNA and a moderate one with albumin, total proteins, transferrin and BMI. Discussion The Spanish version of EdFED is reliable and valid for use in elderly people with dementia. The most appropriate for our environment is the three-factor model, which maintains the original factors, with a slight redistribution of the items. PMID:29486002
Heitor Dos Santos, Maria João; Moreira, Sérgio; Carreiras, Joana; Cooper, Cary; Smeed, Matthew; Reis, Maria de Fátima; Pereira Miguel, José
2018-02-12
The main objective of this work was to translate the English version of ASSET (A Shortened Stress Evaluation Tool) into the Portuguese version and to validate its psychometric properties. Additionally, this work tested the convergent validity of the instrument. The translation and retroversion were conducted by experts and submitted to the authors for approval. Within an observational, cross-sectional study, regarding mental health at the workplace, ASSET together with other scales was applied to a sample of 405 participants. The psychometric validity of the subscales was studied using confirmatory factorial analysis. The factorial structure of ASSET is globally supported by the results, with the Perceptions of Your Job and Attitudes Towards your Organisation subscales requiring slight adjustments in the item structure and the Your Health subscales replicating the original structure. The convergent validity also supports the ASSET, showing that all subscales are significantly correlated with variables used to test convergence. Globally, the results constitute an important contribution to ASSET and open the possibility of its usage among Portuguese-speaking countries. The results provide an evidence on the validity of the instrument and, in particular, of the mental and physical health subscales. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Factor complexity of crash occurrence: An empirical demonstration using boosted regression trees.
Chung, Yi-Shih
2013-12-01
Factor complexity is a characteristic of traffic crashes. This paper proposes a novel method, namely boosted regression trees (BRT), to investigate the complex and nonlinear relationships in high-variance traffic crash data. The Taiwanese 2004-2005 single-vehicle motorcycle crash data are used to demonstrate the utility of BRT. Traditional logistic regression and classification and regression tree (CART) models are also used to compare their estimation results and external validities. Both the in-sample cross-validation and out-of-sample validation results show that an increase in tree complexity provides improved, although declining, classification performance, indicating a limited factor complexity of single-vehicle motorcycle crashes. The effects of crucial variables including geographical, time, and sociodemographic factors explain some fatal crashes. Relatively unique fatal crashes are better approximated by interactive terms, especially combinations of behavioral factors. BRT models generally provide improved transferability than conventional logistic regression and CART models. This study also discusses the implications of the results for devising safety policies. Copyright © 2012 Elsevier Ltd. All rights reserved.
Genomic selection in sugar beet breeding populations
2013-01-01
Background Genomic selection exploits dense genome-wide marker data to predict breeding values. In this study we used a large sugar beet population of 924 lines representing different germplasm types present in breeding populations: unselected segregating families and diverse lines from more advanced stages of selection. All lines have been intensively phenotyped in multi-location field trials for six agronomically important traits and genotyped with 677 SNP markers. Results We used ridge regression best linear unbiased prediction in combination with fivefold cross-validation and obtained high prediction accuracies for all except one trait. In addition, we investigated whether a calibration developed based on a training population composed of diverse lines is suited to predict the phenotypic performance within families. Our results show that the prediction accuracy is lower than that obtained within the diverse set of lines, but comparable to that obtained by cross-validation within the respective families. Conclusions The results presented in this study suggest that a training population derived from intensively phenotyped and genotyped diverse lines from a breeding program does hold potential to build up robust calibration models for genomic selection. Taken together, our results indicate that genomic selection is a valuable tool and can thus complement the genomics toolbox in sugar beet breeding. PMID:24047500
Cross Section Sensitivity and Propagated Errors in HZE Exposures
NASA Technical Reports Server (NTRS)
Heinbockel, John H.; Wilson, John W.; Blatnig, Steve R.; Qualls, Garry D.; Badavi, Francis F.; Cucinotta, Francis A.
2005-01-01
It has long been recognized that galactic cosmic rays are of such high energy that they tend to pass through available shielding materials resulting in exposure of astronauts and equipment within space vehicles and habitats. Any protection provided by shielding materials result not so much from stopping such particles but by changing their physical character in interaction with shielding material nuclei forming, hopefully, less dangerous species. Clearly, the fidelity of the nuclear cross-sections is essential to correct specification of shield design and sensitivity to cross-section error is important in guiding experimental validation of cross-section models and database. We examine the Boltzmann transport equation which is used to calculate dose equivalent during solar minimum, with units (cSv/yr), associated with various depths of shielding materials. The dose equivalent is a weighted sum of contributions from neutrons, protons, light ions, medium ions and heavy ions. We investigate the sensitivity of dose equivalent calculations due to errors in nuclear fragmentation cross-sections. We do this error analysis for all possible projectile-fragment combinations (14,365 such combinations) to estimate the sensitivity of the shielding calculations to errors in the nuclear fragmentation cross-sections. Numerical differentiation with respect to the cross-sections will be evaluated in a broad class of materials including polyethylene, aluminum and copper. We will identify the most important cross-sections for further experimental study and evaluate their impact on propagated errors in shielding estimates.
Marlatt, K L; Greenway, F L; Ravussin, E
2017-04-01
Comparison of percent fat mass across different body composition analysis devices is important given variation in technology accuracy and precision, as well as the growing need for cross-validation of devices often applied across longitudinal studies. We compared EchoMRI-AH and Lunar iDXA quantification of percent body fat (PBF) in 84 adults (43M, 41F), with the mean age 39.7±15.9 years and body mass index (BMI) 26.2±5.3 kg/m 2 . PBF correlated strongly between devices (r>0.95, P<0.0001). A prediction equation was derived in half of the subjects, and the other half were used to cross-validate the proposed equation (EchoMRI-AH PBF=[(0.94 × iDXA PBF)+(0.14 × Age)+(3.3 × Female)-8.83). The mean PBF difference (predicted-measured) in the validation group was not different from 0 (diff=0.27%, 95% confidence interval: -0.42-0.96, P=0.430). Bland-Altman plots showed a bias with higher measured PBF on EchoMRI-AH versus iDXA in all 84 subjects (β=0.13, P<0.0001). The proposed prediction equation was valid in our cross-validation sample, and it has the potential to be applied across multicenter studies.
Bucci, Rosaria; Rongo, Roberto; Zito, Eugenio; Galeotti, Angela; Valletta, Rosa; D'Antò, Vincenzo
2015-03-01
To validate and cross-culturally adapt the Italian version of the Psychological Impact of Dental Aesthetics Questionnaire (PIDAQ) among Italian young adults. After translation, back translation, and cross-cultural adaptation of the English PIDAQ, a first version of the Italian questionnaire was pretested. The final Italian PIDAQ was administered to 598 subjects aged 18-30 years, along with two other instruments: the aesthetic component of the index of orthodontic treatment need (IOTN-AC) and the perception of occlusion scale (POS), which identified the self-reporting grade of malocclusion. Structural validity was assessed by means of factorial analysis, internal consistency was measured with Cronbach's alpha coefficient (α), convergent validity was assessed by means of Spearman correlation, and test-retest reliability was calculated with intra-class correlation coefficient (ICC) and standard measurement error. Criterion validity was evaluated by multivariate and univariate analysis of variance with Bonferroni post hoc tests. The α of the Italian PIDAQ domains ranged between 0.79 and 0.92. The ICC was between 0.81 and 0.90. The mean scores of each PIDAQ domain showed a statistically significant difference when analysed according to the IOTN-AC and POS scores. The satisfactory psychometric properties make PIDAQ a usable tool for future studies on oral health-related quality of life among Italian young adults.