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Sample records for replicate predictive validity

  1. Process chain validation in micro and nano replication

    DEFF Research Database (Denmark)

    Calaon, Matteo

    tranches a standard deviation of 4 % around the calculated average value was assessed. The work is concluded validating the deterministic test structures as a tool to predict, through relocation of measuring positions, replication quality of critical geometries of specific LoC devices. The study showed...

  2. SNP CHARACTERISTICS PREDICT REPLICATION SUCCESS IN ASSOCIATION STUDIES

    Science.gov (United States)

    Gorlov, Ivan P.; Moore, Jason H.; Peng, Bo; Jin, Jennifer L.; Gorlova, Olga Y.; Amos, Christopher I.

    2014-01-01

    Successful independent replication is the most direct approach for distinguishing real genotype-disease associations from false discoveries in Genome Wide Association Studies (GWAS). Selecting SNPs for replication has been primarily based on p-values from the discovery stage, although additional characteristics of SNPs may be used to improve replication success. We used disease-associated SNPs from more than 2,000 published GWASs to identify predictors of SNP reproducibility. SNP reproducibility was defined as a proportion of successful replications among all replication attempts. The study reporting association for the first time was considered to be discovery and all consequent studies targeting the same phenotype replications. We found that −Log(P), where P is a p-value from the discovery study, is the strongest predictor of the SNP reproducibility. Other significant predictors include type of the SNP (e.g. missense vs intronic SNPs) and minor allele frequency. Features of the genes linked to the disease-associated SNP also predict SNP reproducibility. Based on empirically defined rules, we developed a reproducibility score (RS) to predict SNP reproducibility independently of −Log(P). We used data from two lung cancer GWAS studies as well as recently reported disease-associated SNPs to validate RS. Minus Log(P) outperforms RS when the very top SNPs are selected, while RS works better with relaxed selection criteria. In conclusion, we propose an empirical model to predict SNP reproducibility, which can be used to select SNPs for validation and prioritization. PMID:25273843

  3. Predicting Psychiatric Rehabilitation Outcome Using Demographic Characteristics: A Replication

    Science.gov (United States)

    Anthony, William A.; Buell, Gregory J.

    1974-01-01

    Replication was undertaken of a recent study conducted by Buell and Anthony which had found that recidivism and posthospital employment could be predicted by a single demographic variable, number of previous hospitalizations and employment history, respectively. Results of the replication were consistent for posthospital employment but not for…

  4. Poor replication validity of biomedical association studies reported by newspapers

    Science.gov (United States)

    Smith, Andy; Boraud, Thomas; Gonon, François

    2017-01-01

    Objective To investigate the replication validity of biomedical association studies covered by newspapers. Methods We used a database of 4723 primary studies included in 306 meta-analysis articles. These studies associated a risk factor with a disease in three biomedical domains, psychiatry, neurology and four somatic diseases. They were classified into a lifestyle category (e.g. smoking) and a non-lifestyle category (e.g. genetic risk). Using the database Dow Jones Factiva, we investigated the newspaper coverage of each study. Their replication validity was assessed using a comparison with their corresponding meta-analyses. Results Among the 5029 articles of our database, 156 primary studies (of which 63 were lifestyle studies) and 5 meta-analysis articles were reported in 1561 newspaper articles. The percentage of covered studies and the number of newspaper articles per study strongly increased with the impact factor of the journal that published each scientific study. Newspapers almost equally covered initial (5/39 12.8%) and subsequent (58/600 9.7%) lifestyle studies. In contrast, initial non-lifestyle studies were covered more often (48/366 13.1%) than subsequent ones (45/3718 1.2%). Newspapers never covered initial studies reporting null findings and rarely reported subsequent null observations. Only 48.7% of the 156 studies reported by newspapers were confirmed by the corresponding meta-analyses. Initial non-lifestyle studies were less often confirmed (16/48) than subsequent ones (29/45) and than lifestyle studies (31/63). Psychiatric studies covered by newspapers were less often confirmed (10/38) than the neurological (26/41) or somatic (40/77) ones. This is correlated to an even larger coverage of initial studies in psychiatry. Whereas 234 newspaper articles covered the 35 initial studies that were later disconfirmed, only four press articles covered a subsequent null finding and mentioned the refutation of an initial claim. Conclusion Journalists

  5. Predictive validity of the Slovene Matura

    Directory of Open Access Journals (Sweden)

    Valentin Bucik

    2001-09-01

    Full Text Available Passing Matura is the last step of the secondary school graduation, but it is also the entrance ticket for the university. Besides, the summary score of Matura exam takes part in the selection process for the particular university studies in case of 'numerus clausus'. In discussing either aim of Matura important dilemmas arise, namely, is the Matura examination sufficiently exact and rightful procedure to, firstly, use its results for settling starting studying conditions and, secondly, to select validly, reliably and sensibly the best candidates for university studies. There are some questions concerning predictive validity of Matura that should be answered, e.g. (i does Matura as an enrollment procedure add to the qualitaty of the study; (ii is it a better selection tool than entrance examinations formerly used in different faculties in the case of 'numerus clausus'; and (iii is it reasonable to expect high predictive validity of Matura results for success at the university at all. Recent results show that in the last few years the dropout-rate is lower than before, the pass-rate between the first and the second year is higher and the average duration of study per student is shorter. It is clear, however, that it is not possible to simply predict the study success from the Matura results. There are too many factors influencing the success in the university studies. In most examined study programs the correlation between Matura results and study success is positive but moderate, therefore it can not be said categorically that only candidates accepted according to the Matura results are (or will be the best students. Yet it has been shown that Matura is a standardized procedure, comparable across different candidates entering university, and that – when compared entrance examinations – it is more objective, reliable, and hen ce more valid and fair a procedure. In addition, comparable procedures of university recruiting and selection can be

  6. Replication Validity of Initial Association Studies: A Comparison between Psychiatry, Neurology and Four Somatic Diseases

    Science.gov (United States)

    Dumas-Mallet, Estelle; Button, Katherine; Boraud, Thomas; Munafo, Marcus; Gonon, François

    2016-01-01

    Context There are growing concerns about effect size inflation and replication validity of association studies, but few observational investigations have explored the extent of these problems. Objective Using meta-analyses to measure the reliability of initial studies and explore whether this varies across biomedical domains and study types (cognitive/behavioral, brain imaging, genetic and “others”). Methods We analyzed 663 meta-analyses describing associations between markers or risk factors and 12 pathologies within three biomedical domains (psychiatry, neurology and four somatic diseases). We collected the effect size, sample size, publication year and Impact Factor of initial studies, largest studies (i.e., with the largest sample size) and the corresponding meta-analyses. Initial studies were considered as replicated if they were in nominal agreement with meta-analyses and if their effect size inflation was below 100%. Results Nominal agreement between initial studies and meta-analyses regarding the presence of a significant effect was not better than chance in psychiatry, whereas it was somewhat better in neurology and somatic diseases. Whereas effect sizes reported by largest studies and meta-analyses were similar, most of those reported by initial studies were inflated. Among the 256 initial studies reporting a significant effect (p<0.05) and paired with significant meta-analyses, 97 effect sizes were inflated by more than 100%. Nominal agreement and effect size inflation varied with the biomedical domain and study type. Indeed, the replication rate of initial studies reporting a significant effect ranged from 6.3% for genetic studies in psychiatry to 86.4% for cognitive/behavioral studies. Comparison between eight subgroups shows that replication rate decreases with sample size and “true” effect size. We observed no evidence of association between replication rate and publication year or Impact Factor. Conclusion The differences in reliability

  7. Validation of computationally predicted substrates for laccase

    Directory of Open Access Journals (Sweden)

    Reena

    2014-10-01

    Full Text Available Present study reports the validation (oxidation of computationally predicted oxidation of xenobiotic contaminants by commercially available pure laccase from Trametes versicolor. Selected contaminants were predicted as potential targets for laccase oxidation by using in-silico docking tool. The oxidation by laccase was measured by change in absorbance at specific λ max of each compound. Sinapic acid and tyrosine were taken as positive and negative controls, respectively. Oxidation was observed in m-chlorophenol, 2,4 di-chlorophenol, 2,4,6 tri-chlorophenol, captan, atrazine and thiodicarb, except malathion, which showed no activity. It could be speculated that the predicted substrates showing oxidation shared homology at structural and chemical level with positive control compounds. In case of malathion, structural non-homology with sinapic acid could be attributed to its inactivity towards laccase that required further structural analysis. Thus, a remediation tool proposing an advanced remediation approach combining the application of theoretical in-silico method and subsequent experimental validation using pure laccase could be proposed. As number and type of xenobiotics increase, the unfeasibility to screen them experimentally for bioremediation also rise. This approach would be useful to reduce the time and cost required in other screening methods.

  8. Testing the Predictive Validity and Construct of Pathological Video Game Use.

    Science.gov (United States)

    Groves, Christopher L; Gentile, Douglas; Tapscott, Ryan L; Lynch, Paul J

    2015-12-15

    Three studies assessed the construct of pathological video game use and tested its predictive validity. Replicating previous research, Study 1 produced evidence of convergent validity in 8th and 9th graders (N = 607) classified as pathological gamers. Study 2 replicated and extended the findings of Study 1 with college undergraduates (N = 504). Predictive validity was established in Study 3 by measuring cue reactivity to video games in college undergraduates (N = 254), such that pathological gamers were more emotionally reactive to and provided higher subjective appraisals of video games than non-pathological gamers and non-gamers. The three studies converged to show that pathological video game use seems similar to other addictions in its patterns of correlations with other constructs. Conceptual and definitional aspects of Internet Gaming Disorder are discussed.

  9. Testing the Predictive Validity and Construct of Pathological Video Game Use

    Directory of Open Access Journals (Sweden)

    Christopher L. Groves

    2015-12-01

    Full Text Available Three studies assessed the construct of pathological video game use and tested its predictive validity. Replicating previous research, Study 1 produced evidence of convergent validity in 8th and 9th graders (N = 607 classified as pathological gamers. Study 2 replicated and extended the findings of Study 1 with college undergraduates (N = 504. Predictive validity was established in Study 3 by measuring cue reactivity to video games in college undergraduates (N = 254, such that pathological gamers were more emotionally reactive to and provided higher subjective appraisals of video games than non-pathological gamers and non-gamers. The three studies converged to show that pathological video game use seems similar to other addictions in its patterns of correlations with other constructs. Conceptual and definitional aspects of Internet Gaming Disorder are discussed.

  10. Testing the Predictive Validity and Construct of Pathological Video Game Use

    Science.gov (United States)

    Groves, Christopher L.; Gentile, Douglas; Tapscott, Ryan L.; Lynch, Paul J.

    2015-01-01

    Three studies assessed the construct of pathological video game use and tested its predictive validity. Replicating previous research, Study 1 produced evidence of convergent validity in 8th and 9th graders (N = 607) classified as pathological gamers. Study 2 replicated and extended the findings of Study 1 with college undergraduates (N = 504). Predictive validity was established in Study 3 by measuring cue reactivity to video games in college undergraduates (N = 254), such that pathological gamers were more emotionally reactive to and provided higher subjective appraisals of video games than non-pathological gamers and non-gamers. The three studies converged to show that pathological video game use seems similar to other addictions in its patterns of correlations with other constructs. Conceptual and definitional aspects of Internet Gaming Disorder are discussed. PMID:26694472

  11. Predictive Validity of the Gesell School Readiness Tests.

    Science.gov (United States)

    Graue, M. Elizabeth; Shepard, Lorrie A.

    1989-01-01

    Examined the predictive validity of the Gesell School Readiness Tests by correlating measured developmental age and performance in 151 first-grade students. Results show a positive relationship between developmental age and report card grades, modest predictive validity for standardized tests, and low validity for teacher judgment of first-grade…

  12. Ori-Finder 2, an integrated tool to predict replication origins in the archaeal genomes

    Directory of Open Access Journals (Sweden)

    Hao eLuo

    2014-09-01

    Full Text Available DNA replication is one of the most basic processes in all three domains of cellular life. With the advent of the post-genomic era, the increasing number of complete archaeal genomes has created an opportunity for exploration of the molecular mechanisms for initiating cellular DNA replication by in vivo experiments as well as in silico analysis. However, the location of replication origins (oriCs in many sequenced archaeal genomes remains unknown. We present a web-based tool Ori-Finder 2 to predict oriCs in the archaeal genomes automatically, based on the integrated method comprising the analysis of base composition asymmetry using the Z-curve method, the distribution of Origin Recognition Boxes (ORBs identified by FIMO tool, and the occurrence of genes frequently close to oriCs. The web server is also able to analyze the unannotated genome sequences by integrating with gene prediction pipelines and BLAST software for gene identification and function annotation. The result of the predicted oriCs is displayed as an HTML table, which offers an intuitive way to browse the result in graphical and tabular form. The software presented here is accurate for the genomes with single oriC, but it does not necessarily find all the origins of replication for the genomes with multiple oriCs. Ori-Finder 2 aims to become a useful platform for the identification and analysis of oriCs in the archaeal genomes, which would provide insight into the replication mechanisms in archaea. The web server is freely available at http://tubic.tju.edu.cn/Ori-Finder2/.

  13. Evaluating the Predictive Validity of Graduate Management Admission Test Scores

    Science.gov (United States)

    Sireci, Stephen G.; Talento-Miller, Eileen

    2006-01-01

    Admissions data and first-year grade point average (GPA) data from 11 graduate management schools were analyzed to evaluate the predictive validity of Graduate Management Admission Test[R] (GMAT[R]) scores and the extent to which predictive validity held across sex and race/ethnicity. The results indicated GMAT verbal and quantitative scores had…

  14. Evaluating the Predictive Validity of Graduate Management Admission Test Scores

    Science.gov (United States)

    Sireci, Stephen G.; Talento-Miller, Eileen

    2006-01-01

    Admissions data and first-year grade point average (GPA) data from 11 graduate management schools were analyzed to evaluate the predictive validity of Graduate Management Admission Test[R] (GMAT[R]) scores and the extent to which predictive validity held across sex and race/ethnicity. The results indicated GMAT verbal and quantitative scores had…

  15. College of the Canyons Predictive Validity Studies.

    Science.gov (United States)

    College of the Canyons, Valencia, CA. Office of Institutional Development.

    Matriculation regulations in California require that community colleges which adopt standardized placement tests demonstrate that the tests are valid predictors of future course success. A positive correlation of at least .35 between test score and subsequent student performance in a particular course is needed to demonstrate the predictive…

  16. Predicting Marital Success with PREPARE: A Predictive Validity Study.

    Science.gov (United States)

    Fowers, Blaine J.; Olson, David H.

    1986-01-01

    Assessed the utility of the premarital inventory, PREPARE, in predicting marital success. Conducted a three-year follow-up study with couples (N=164) who took PREPARE during their engagement. Found that the PREPARE scores from three months before marriage could predict with 80-90% accuracy which couples were separated and divorced from those that…

  17. 3D structure prediction of replication factor C subunits (RFC and their interactome in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Mohamed Ragab Abdel Gawwad

    2013-06-01

    Full Text Available DNA stress can causes potentially spontaneous genome damage during DNA replication process. Proteins involved in this process are DNA-dependent ATPases, required for replication and repair. In this study the 3-D structure of RFC protein subunits in Arabidopsis thaliana: RFC1, RFC2, RFC3, RFC4 and RFC5 are predicted and confirmed by Ramachadran plot. The amino acid sequences are highly similar to the sequences of the homologous human RFC 140-, 37-, 36-, 40-, and 38 kDa subunits, respectively, and also show amino acid sequence similarity to functionally homologous proteins from E. coli. All five subunits show conserved regions characteristic of ATP/GTP-binding proteins and have significant degree of similarity among each other. The segments of conserved amino acid sequences that define a family of related proteins have been identified. RFC1 is identical to CDC44, a gene identified as a cell division cycle gene encoding a protein involved in DNA metabolism. Subcellular localization and interactions of each protein RFC protein subunit is determined. It subsequently became clear that RFC proteins and their interactome have functions in cell cycle regulation and/or DNA replication and repair processes. In addition, AtRFC subunits are controlling the biosynthesis of salicylic and salicylic acid-mediated defense responses in Arabidopsis.

  18. DNAskew: Statistical Analysis of Base Compositional Asymmetry and Prediction of Replication Boundaries in the Genome Sequences

    Institute of Scientific and Technical Information of China (English)

    Xiang-RuMA; Shao-BoXIAO; Ai-ZhenGUO; Jian-QiangLUE; Huan-ChunCHEN

    2004-01-01

    Sueoka and Lobry declared respectively that, in the absence of bias between the two DNA strands for mutation and selection, the base composition within each strand should be A=T and C=G (this state is called Parity Rule type 2, PR2). However, the genome sequences of many bacteria, vertebrates and viruses showed asymmetries in base composition and gene direction. To determine the relationship of base composition skews with replication orientation, gene function, codon usage biases and phylogenetic evolution,in this paper a program called DNAskew was developed for the statistical analysis of strand asymmetry and codon composition bias in the DNA sequence. In addition, the program can also be used to predict the replication boundaries of genome sequences. The method builds on the fact that there are compositional asymmetries between the leading and the lagging strand for replication. DNAskew was written in Perl script language and implemented on the LINUX operating system. It works quickly with annotated or unannotated sequences in GBFF (GenBank flatfile) or fasta format. The source code is freely available for academic use at http://www.epizooty.com/pub/stat/DNAskew.

  19. Improved interpretation and validation of CFD predictions

    DEFF Research Database (Denmark)

    Popiolek, Z.; Melikov, Arsen Krikor

    2004-01-01

    The mean velocity in rooms predicted by CFD simulations based on RANS equations differs from the mean (in time) magnitude of the velocity, i.e. the mean speed, in rooms measured by low velocity thermal anemometers with omnidirectional sensor. This discrepancy results in incorrect thermal comfort ...

  20. Validation of Biomarker-based risk prediction models

    OpenAIRE

    Taylor, Jeremy M.G.; Ankerst, Donna P.; Andridge, Rebecca R.

    2008-01-01

    The increasing availability and use of predictive models to facilitate informed decision making highlights the need for careful assessment of the validity of these models. In particular, models involving biomarkers require careful validation for two reasons: issues with overfitting when complex models involve a large number of biomarkers, and inter-laboratory variation in assays used to measure biomarkers. In this paper we distinguish between internal and external statistical validation. Inte...

  1. Predicting Lexical Priming Effects from Distributional Semantic Similarities: A Replication with Extension.

    Science.gov (United States)

    Günther, Fritz; Dudschig, Carolin; Kaup, Barbara

    2016-01-01

    In two experiments, we attempted to replicate and extend findings by Günther et al. (2016) that word similarity measures obtained from distributional semantics models-Latent Semantic Analysis (LSA) and Hyperspace Analog to Language (HAL)-predict lexical priming effects. To this end, we used the pseudo-random method to generate item material while systematically controlling for word similarities introduced by Günther et al. (2016) which was based on LSA cosine similarities (Experiment 1) and HAL cosine similarities (Experiment 2). Extending the original study, we used semantic spaces created from far larger corpora, and implemented several additional methodological improvements. In Experiment 1, we only found a significant effect of HAL cosines on lexical decision times, while we found significant effects for both LSA and HAL cosines in Experiment 2. As further supported by an analysis of the pooled data from both experiments, this indicates that HAL cosines are a better predictor of priming effects than LSA cosines. Taken together, the results replicate the finding that priming effects can be predicted from distributional semantic similarity measures.

  2. Validation of a tuber blight (Phytophthora infestans) prediction model

    Science.gov (United States)

    Potato tuber blight caused by Phytophthora infestans accounts for significant losses in storage. There is limited published quantitative data on predicting tuber blight. We validated a tuber blight prediction model developed in New York with cultivars Allegany, NY 101, and Katahdin using independent...

  3. Predicting School Readiness: The Validity of Developmental Age.

    Science.gov (United States)

    Wood, Chip; And Others

    1984-01-01

    Examination of the predictive validity of the Gesell School Readiness Screening Test with 84 kindergarten-age children found the procedure effective in predicting child success or failure in kindergarten and that within four-six years the chronological age of children entering kindergarten is unrelated to eventual success of failure in…

  4. Infrared ship signature prediction, model validation and sky radiance

    NARCIS (Netherlands)

    Neele, F.P.

    2005-01-01

    The increased interest during the last decade in the infrared signature of (new) ships results in a clear need of validated infrared signature prediction codes. This paper presents the results of comparing an in-house developed signature prediction code with measurements made in the 3-5 μm band in b

  5. Factors affecting the predictive validity of the Braden Scale.

    Science.gov (United States)

    Capobianco, M L; McDonald, D D

    1996-01-01

    This descriptive correlational study explored the predictive validity of the Braden Scale and factors affecting it A Braden score was determined within 4 hours of admission for 50 adult medical/surgical inpatients. Independent skin assessments were made three times a week and at discharge. Fourteen patients (28%) developed pressure ulcers. A Braden score cutoff of 18 or less resulted in a 71% sensitivity, 83% specificity, 63% predictive value of a positive test, and 88% predictive value of a negative test. Three of the four patients incorrectly predicted to be not at risk scored "inadequate" on the nutrition subscale. Two of the four also were underweight. Of the six patients incorrectly predicted at risk for a pressure ulcer, three had been placed on air mattresses and were receiving levothyroxine (Synthroid). This study provides further evidence of the Braden Scale's predictive validity. The results suggest that patients who are underweight or getting inadequate nutrition be considered at increased risk for pressure ulcers.

  6. Validation, replication, and sensitivity testing of Heckman-type selection models to adjust estimates of HIV prevalence.

    Directory of Open Access Journals (Sweden)

    Samuel J Clark

    Full Text Available A recent study using Heckman-type selection models to adjust for non-response in the Zambia 2007 Demographic and Health Survey (DHS found a large correction in HIV prevalence for males. We aim to validate this finding, replicate the adjustment approach in other DHSs, apply the adjustment approach in an external empirical context, and assess the robustness of the technique to different adjustment approaches. We used 6 DHSs, and an HIV prevalence study from rural South Africa to validate and replicate the adjustment approach. We also developed an alternative, systematic model of selection processes and applied it to all surveys. We decomposed corrections from both approaches into rate change and age-structure change components. We are able to reproduce the adjustment approach for the 2007 Zambia DHS and derive results comparable with the original findings. We are able to replicate applying the approach in several other DHSs. The approach also yields reasonable adjustments for a survey in rural South Africa. The technique is relatively robust to how the adjustment approach is specified. The Heckman selection model is a useful tool for assessing the possibility and extent of selection bias in HIV prevalence estimates from sample surveys.

  7. Predicting lexical priming effects from distributional semantic similarities: A replication with extension

    Directory of Open Access Journals (Sweden)

    Fritz Günther

    2016-10-01

    Full Text Available In two experiments, we attempted to replicate findings by Günther, Dudschig &Kaup (2016 that word similarity measures obtained from distributional semantics models -Latent Semantic Analysis (LSA and Hyperspace Analogue to Language (HAL - predictlexical priming effects. To this end, we used the pseudo-random method to generate itemmaterial while systematically controlling for word similarities introduced by Günther et al.,which was based on LSA cosine similarities (Experiment 1 and HAL cosine similarities(Experiment 2. Contrary to the original study, we used semantic spaces created from farlarger corpora, and implemented several additional methodological improvements. InExperiment 1, we only found a significant effect of HAL cosines on lexical decision times,while we found significant effects for both LSA and HAL cosines in Experiment 2. Asfurther supported by an analysis of the pooled data from both experiments, this indicatesthat HAL cosines are a better predictor of priming effects than LSA cosines. Takentogether, the results replicate the finding that priming effects can be predicted fromdistributional semantic similarity measures.

  8. Quality of life among people with multiple sclerosis: Replication of a three-factor prediction model.

    Science.gov (United States)

    Bishop, Malachy; Rumrill, Phillip D; Roessler, Richard T

    2015-01-01

    This article presents a replication of Rumrill, Roessler, and Fitzgerald's 2004 analysis of a three-factor model of the impact of multiple sclerosis (MS) on quality of life (QOL). The three factors in the original model included illness-related, employment-related, and psychosocial adjustment factors. To test hypothesized relationships between QOL and illness-related, employment-related, and psychosocial variables using data from a survey of the employment concerns of Americans with MS (N = 1,839). An ex post facto, multiple correlational design was employed incorporating correlational and multiple regression analyses. QOL was positively related to educational level, employment status, job satisfaction, and job-match, and negatively related to number of symptoms, severity of symptoms, and perceived stress level. The three-factor model explained approximately 37 percent of the variance in QOL scores. The results of this replication confirm the continuing value of the three-factor model for predicting the QOL of adults with MS, and demonstrate the importance of medical, mental health, and vocational rehabilitation interventions and services in promoting QOL.

  9. Examining the Validity of Cyclothymic Disorder in a Youth Sample: Replication and Extension

    Science.gov (United States)

    Van Meter, Anna; Youngstrom, Eric A.; Demeter, Christine; Findling, Robert L.

    2013-01-01

    DSM-IV-TR defines four subtypes of bipolar disorder (BP): bipolar I, bipolar II, cyclothymic disorder and bipolar not otherwise specified (NOS). However, cyclothymic disorder in children is rarely researched, or often subsumed in an "NOS" category. The present study tests the replicability of findings from an earlier study, and expands on the…

  10. Simian Immunodeficiency Virus Disease Course Is Predicted by the Extent of Virus Replication during Primary Infection

    Science.gov (United States)

    Staprans, Silvija I.; Dailey, Peter J.; Rosenthal, Ann; Horton, Chris; Grant, Robert M.; Lerche, Nicholas; Feinberg, Mark B.

    1999-01-01

    To elucidate the relationship between early viral infection events and immunodeficiency virus disease progression, quantitative-competitive and branched-DNA methods of simian immunodeficiency virus (SIV) RNA quantitation were cross-validated and used to measure viremia following infection of rhesus macaques with the pathogenic SIVmac251 virus isolate. Excellent correlation between the methods suggests that both accurately approximate SIV copy number. Plasma viremia was evident 4 days postinfection, and rapid viral expansion led to peak viremia levels of 107 to 109 SIV RNA copies/ml by days 8 to 17. Limited resolution of primary viremia was accompanied by relatively short, though variable, times to the development of AIDS (81 to 630 days). The persistent high-level viremia observed following intravenous inoculation of SIVmac251 explains the aggressive disease course in this model. Survival analyses demonstrated that the disease course is established 8 to 17 days postinfection, when peak viremia is observed. The most significant predictor of disease progression was the extent of viral decline following peak viremia; larger decrements in viremia were associated with both lower steady-state viremia (P = 0.0005) and a reduced hazard of AIDS (P = 0.004). The data also unexpectedly suggested that following SIVmac251 infection, animals with the highest peak viremia were better able to control virus replication rather than more rapidly developing disease. Analysis of early viral replication dynamics should help define host responses that protect from disease progression and should provide quantitative measures to assess the extent to which protective responses may be induced by prophylactic vaccination. PMID:10233944

  11. ASC Predictive Science Academic Alliance Program Verification and Validation Whitepaper

    Energy Technology Data Exchange (ETDEWEB)

    Klein, R; Graziani, F; Trucano, T

    2006-03-31

    The purpose of this whitepaper is to provide a framework for understanding the role that verification and validation (V&V) are expected to play in successful ASC Predictive Science Academic Alliance (PSAA) Centers and projects. V&V have been emphasized in the recent specification of the PSAA (NNSA, 2006): (1) The resulting simulation models lend themselves to practical verification and validation methodologies and strategies that should include the integrated use of experimental and/or observational data as a key part of model and sub-model validation, as well as demonstrations of numerical convergence and accuracy for code verification. (2) Verification, validation and prediction methodologies and results must be much more strongly emphasized as research topics and demonstrated via the proposed simulations. (3) It is mandatory that proposals address the following two topics: (a) Predictability in science & engineering; and (b) Verification & validation strategies for large-scale simulations, including quantification of uncertainty and numerical convergence. We especially call attention to the explicit coupling of computational predictability and V&V in the third bullet above. In this whitepaper we emphasize this coupling, and provide concentrated guidance for addressing item 2. The whitepaper has two main components. First, we provide a brief and high-level tutorial on V&V that emphasizes critical elements of the program. Second, we state a set of V&V-related requirements that successful PSAA proposals must address.

  12. Predicting and validating protein interactions using network structure.

    Directory of Open Access Journals (Sweden)

    Pao-Yang Chen

    Full Text Available Protein interactions play a vital part in the function of a cell. As experimental techniques for detection and validation of protein interactions are time consuming, there is a need for computational methods for this task. Protein interactions appear to form a network with a relatively high degree of local clustering. In this paper we exploit this clustering by suggesting a score based on triplets of observed protein interactions. The score utilises both protein characteristics and network properties. Our score based on triplets is shown to complement existing techniques for predicting protein interactions, outperforming them on data sets which display a high degree of clustering. The predicted interactions score highly against test measures for accuracy. Compared to a similar score derived from pairwise interactions only, the triplet score displays higher sensitivity and specificity. By looking at specific examples, we show how an experimental set of interactions can be enriched and validated. As part of this work we also examine the effect of different prior databases upon the accuracy of prediction and find that the interactions from the same kingdom give better results than from across kingdoms, suggesting that there may be fundamental differences between the networks. These results all emphasize that network structure is important and helps in the accurate prediction of protein interactions. The protein interaction data set and the program used in our analysis, and a list of predictions and validations, are available at http://www.stats.ox.ac.uk/bioinfo/resources/PredictingInteractions.

  13. Experimental validation of boundary element methods for noise prediction

    Science.gov (United States)

    Seybert, A. F.; Oswald, Fred B.

    1992-01-01

    Experimental validation of methods to predict radiated noise is presented. A combined finite element and boundary element model was used to predict the vibration and noise of a rectangular box excited by a mechanical shaker. The predicted noise was compared to sound power measured by the acoustic intensity method. Inaccuracies in the finite element model shifted the resonance frequencies by about 5 percent. The predicted and measured sound power levels agree within about 2.5 dB. In a second experiment, measured vibration data was used with a boundary element model to predict noise radiation from the top of an operating gearbox. The predicted and measured sound power for the gearbox agree within about 3 dB.

  14. On objectivity and validity of oral examinations in psychology – A replication

    Directory of Open Access Journals (Sweden)

    Karl Westhoff

    2010-09-01

    Full Text Available A hierarchy of requirements applying to practising psychologists is the basis of a concept for oral examinations in psychological assessment. A study on the objectivity of oral examinations was replicated. We found very high correlations between the evaluations of examiner and assessor and high correlations between the examinees’ self-evaluations after the exam. Examinees’ self-evaluations before the examinations correlated at about 0.48 with the marks in the oral examina-tion. The results concerning preparation do not uniformly show that preparation in a group and mutual examination lead to better marks compared to preparation alone.

  15. Identification of valid reference genes for microRNA expression studies in a hepatitis B virus replicating liver cell line

    DEFF Research Database (Denmark)

    Jacobsen, Kari Stougaard; Nielsen, Kirstine Overgaard; Nordmann Winther, Thilde;

    2016-01-01

    BACKGROUND: MicroRNAs are regulatory molecules and suggested as non-invasive biomarkers for molecular diagnostics and prognostics. Altered expression levels of specific microRNAs are associated with hepatitis B virus infection and hepatocellular carcinoma. We previously identified differentially...... of hepatitis B virus expression vectors. RT-qPCR is the preferred method for microRNA studies, and a careful normalisation strategy, verifying the optimal set of reference genes, is decisive for correctly evaluating microRNA expression levels. The aim of this study was to provide valid reference genes...... identified miR-24-3p, miR-151a-5p, and miR-425-5p as the most valid combination of reference genes for microRNA RT-qPCR studies in our hepatitis B virus replicating HepG2 cell model....

  16. The Predictive Validity of the Phelps Kindergarten Readiness Scale

    Science.gov (United States)

    Augustyniak, Kristine M.; Cook-Cottone, Catherine P.; Calabrese, Nancy

    2004-01-01

    This study assesses the predictive validity of the Phelps Kindergarten Readiness Scale (PKRS) for later academic achievement and explores the utility of a domain-specific measure of kindergarten readiness. Kindergarten readiness scores were significantly correlated with both math and language arts achievement as measured by New York State…

  17. Predictive Validity of the Gesell School Readiness Tests.

    Science.gov (United States)

    Graue, M. Elizabeth; Shepard, Lorrie A.

    In response to the fact that technical standards for screening and placement tests must be more rigorous than those for readiness tests, the predictive validity of the Gesell School Readiness Tests (GSRT) was examined. The purpose of the GSRT, a commonly used screening instrument, is the assessment of children's developmental behaviors to aid in…

  18. Predictive validity of the Hand Arm Risk assessment Method (HARM)

    NARCIS (Netherlands)

    Douwes, M.; Boocock, M.; Coenen, P.; Heuvel, S. van den; Bosch, T.

    2014-01-01

    The Hand Arm Risk assessment Method (HARM) is a simplified risk assessment method for determining musculoskeletal symptoms to the arm, neck and/or shoulder posed by hand-arm tasks of the upper body. The purpose of this study was to evaluate the predictive validity of HARM using data collected from a

  19. Validation of a multi-objective, predictive urban traffic model

    NARCIS (Netherlands)

    Wilmink, I.R.; Haak, P. van den; Woldeab, Z.; Vreeswijk, J.

    2013-01-01

    This paper describes the results of the verification and validation of the ecoStrategic Model, which was developed, implemented and tested in the eCoMove project. The model uses real-time and historical traffic information to determine the current, predicted and desired state of traffic in a network

  20. A robust approach to QMU, validation, and conservative prediction.

    Energy Technology Data Exchange (ETDEWEB)

    Segalman, Daniel Joseph; Paez, Thomas Lee; Bauman, Lara E

    2013-01-01

    A systematic approach to defining margin in a manner that incorporates statistical information and accommodates data uncertainty, but does not require assumptions about specific forms of the tails of distributions is developed. This approach extends to calculations underlying validation assessment and quantitatively conservative predictions.

  1. Predictive validity of the strain index in manufacturing facilities.

    Science.gov (United States)

    Rucker, Nathan; Moore, J Steven

    2002-01-01

    The Strain Index is a job analysis method for determining if workers are exposed to increased risk of developing distal upper extremity disorders. Its predictive and external validity was initially demonstrated in a pork processing plant. The purpose of this study was to evaluate its predictive validity in two manufacturing plants. While blinded to health outcomes, investigators analyzed the right and left sides of 28 single-task jobs using the Strain Index and classified them as "hazardous" or "safe" based on the Strain Index score. Subsequently, OSHA 200 logs were used to ascertain the occurrence of distal upper extremity disorders retrospectively. If at least one such disorder occurred on the right or left side during the prior three years, that side was classified as "positive." If no such disorder was reported during the prior three years, that side was classified as "negative." When comparing sides, symmetry between morbidity and hazard classification was required. When comparing jobs, such symmetry was not required. Evidence of association between the hazard classifications and the morbidity classifications for the 56 sides and the 28 jobs was evaluated using 2 x 2 contingency tables. For the sides, the association between hazard classification and morbidity classification was statistically significant with an empirical odds ratio of 73.2. The sensitivity, specificity, positive predictive value, and negative predictive value were 1.00, 0.84, 0.47, and 1.00. Similar results were noted for the jobs--the empirical odds ratio was 106.6, and the sensitivity, specificity, positive predictive value, and negative predictive value were 1.00, 0.91, 0.75, and 1.00. While these results provide additional evidence of the Strain Index's external validity and predictive validity, it should be noted that these jobs involved the performance of single tasks.

  2. Predictive validity of the Strain Index in turkey processing.

    Science.gov (United States)

    Knox, K; Moore, J S

    2001-05-01

    The Strain Index is a job analysis method for determining if workers are exposed to increased risk of developing distal upper extremity disorders. Its predictive and external validity was initially demonstrated in a pork processing plant. The purpose of this study was to evaluate the predictive validity of the Strain Index in one turkey processing plant. While blinded to health outcomes, investigators analyzed the right and left sides of workers in 28 jobs using the Strain Index and classified them as "hazardous" or "safe" based on the Strain Index score. Subsequently, OSHA 200 logs were used to ascertain the occurrence of distal upper extremity disorders retrospectively. If at least one such disorder had occurred on the right or left side during the previous 3 years, that side was classified as "positive." If no such disorder was reported during the previous 3 years, that side was classified as "negative." When comparing sides, symmetry between morbidity and hazard classification was required. When comparing jobs, such symmetry was not required. Evidence of association between the hazard classifications and the morbidity classifications for the 56 sides and the 28 jobs was evaluated using 2 x 2 contingency tables. For the sides, the association between hazard classification and morbidity classification was statistically significant, with an odds ratio of 22.0. The sensitivity, specificity, positive predictive value, and negative predictive value were 0.86, 0.79, 0.92, and 0.65, respectively. Similar results were noted for the jobs--the odds ratio was 50.0, and the sensitivity, specificity, positive predictive value, and negative predictive value were 0.91, 0.83, 0.95, and 0.71. These results provide additional evidence of the external validity and predictive validity of the Strain Index.

  3. Validity of Vocational Aspirations and Interest Inventories: Extended, Replicated, and Reinterpreted.

    Science.gov (United States)

    Holland, John L.; And Others

    1990-01-01

    Found classified vocational aspirations of 467 male and 250 female Navy recruits superior to Vocational Preference Inventory (VPI). Predictions for subjects with coherent vocational aspirations were very predictive over short time interval. Hypothesized links between coherence of vocational aspirations and Identity Scale, NEO Personality Inventory…

  4. A prediction model for ocular damage - Experimental validation.

    Science.gov (United States)

    Heussner, Nico; Vagos, Márcia; Spitzer, Martin S; Stork, Wilhelm

    2015-08-01

    With the increasing number of laser applications in medicine and technology, accidental as well as intentional exposure of the human eye to laser sources has become a major concern. Therefore, a prediction model for ocular damage (PMOD) is presented within this work and validated for long-term exposure. This model is a combination of a raytracing model with a thermodynamical model of the human and an application which determines the thermal damage by the implementation of the Arrhenius integral. The model is based on our earlier work and is here validated against temperature measurements taken with porcine eye samples. For this validation, three different powers were used: 50mW, 100mW and 200mW with a spot size of 1.9mm. Also, the measurements were taken with two different sensing systems, an infrared camera and a fibre optic probe placed within the tissue. The temperatures were measured up to 60s and then compared against simulations. The measured temperatures were found to be in good agreement with the values predicted by the PMOD-model. To our best knowledge, this is the first model which is validated for both short-term and long-term irradiations in terms of temperature and thus demonstrates that temperatures can be accurately predicted within the thermal damage regime. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Ensemble approach to predict specificity determinants: benchmarking and validation

    Directory of Open Access Journals (Sweden)

    Panchenko Anna R

    2009-07-01

    Full Text Available Abstract Background It is extremely important and challenging to identify the sites that are responsible for functional specification or diversification in protein families. In this study, a rigorous comparative benchmarking protocol was employed to provide a reliable evaluation of methods which predict the specificity determining sites. Subsequently, three best performing methods were applied to identify new potential specificity determining sites through ensemble approach and common agreement of their prediction results. Results It was shown that the analysis of structural characteristics of predicted specificity determining sites might provide the means to validate their prediction accuracy. For example, we found that for smaller distances it holds true that the more reliable the prediction method is, the closer predicted specificity determining sites are to each other and to the ligand. Conclusion We observed certain similarities of structural features between predicted and actual subsites which might point to their functional relevance. We speculate that majority of the identified potential specificity determining sites might be indirectly involved in specific interactions and could be ideal target for mutagenesis experiments.

  6. Replication of LDL GWAs hits in PROSPER/PHASE as validation for future (pharmacogenetic analyses

    Directory of Open Access Journals (Sweden)

    Stott David J

    2011-10-01

    Full Text Available Abstract Background The PHArmacogenetic study of Statins in the Elderly at risk (PHASE is a genome wide association study in the PROspective Study of Pravastatin in the Elderly at risk for vascular disease (PROSPER that investigates the genetic variation responsible for the individual variation in drug response to pravastatin. Statins lower LDL-cholesterol in general by 30%, however not in all subjects. Moreover, clinical response is highly variable and adverse effects occur in a minority of patients. In this report we first describe the rationale of the PROSPER/PHASE project and second show that the PROSPER/PHASE study can be used to study pharmacogenetics in the elderly. Methods The genome wide association study (GWAS was conducted using the Illumina 660K-Quad beadchips following manufacturer's instructions. After a stringent quality control 557,192 SNPs in 5,244 subjects were available for analysis. To maximize the availability of genetic data and coverage of the genome, imputation up to 2.5 million autosomal CEPH HapMap SNPs was performed with MACH imputation software. The GWAS for LDL-cholesterol is assessed with an additive linear regression model in PROBABEL software, adjusted for age, sex, and country of origin to account for population stratification. Results Forty-two SNPs reached the GWAS significant threshold of p = 5.0e-08 in 5 genomic loci (APOE/APOC1; LDLR; FADS2/FEN1; HMGCR; PSRC1/CELSR5. The top SNP (rs445925, chromosome 19 with a p-value of p = 2.8e-30 is located within the APOC1 gene and near the APOE gene. The second top SNP (rs6511720, chromosome 19 with a p-value of p = 5.22e-15 is located within the LDLR gene. All 5 genomic loci were previously associated with LDL-cholesterol levels, no novel loci were identified. Replication in WOSCOPS and CARE confirmed our results. Conclusion With the GWAS in the PROSPER/PHASE study we confirm the previously found genetic associations with LDL-cholesterol levels. With this proof

  7. Validation of the Cyberchondria Severity Scale (CSS): replication and extension with bifactor modeling.

    Science.gov (United States)

    Norr, Aaron M; Allan, Nicholas P; Boffa, Joseph W; Raines, Amanda M; Schmidt, Norman B

    2015-04-01

    Internet help seeking behaviors are increasingly common. Despite the positives associated with technology, cyberchondria, or the process of increased anxiety in response to internet medical information seeking, is on the rise. The Cyberchondria Severity Scale (CSS) was recently developed to provide a valid measure of cyberchondria across multiple dimensions. The current study sought to extend previous work on the CSS factor structure by examining a bifactor model. Participants (N=526) from a community sample completed the CSS via online crowd sourcing. Results revealed that the bifactor model of the CSS provided superior fit to the data, suggesting that it is useful to conceptualize the CSS as containing a General Cyberchondria factor that is orthogonal to its subfactors. Similar to previous work, the CSS Mistrust factor does not appear to be necessary to this construct. Finally, results revealed unique relations between General and Specific Cyberchondria factors with lower-order health anxiety dimensions. Copyright © 2015. Published by Elsevier Ltd.

  8. Slip Validation and Prediction for Mars Exploration Rovers

    Directory of Open Access Journals (Sweden)

    Jeng Yen

    2008-04-01

    Full Text Available This paper presents a novel technique to validate and predict the rover slips on Martian surface for NASA’s Mars Exploration Rover mission (MER. Different from the traditional approach, the proposed method uses the actual velocity profile of the wheels and the digital elevation map (DEM from the stereo images of the terrain to formulate the equations of motion. The six wheel speed from the empirical encoder data comprises the vehicle's velocity, and the rover motion can be estimated using mixed differential and algebraic equations. Applying the discretization operator to these equations, the full kinematics state of the rover is then resolved by the configuration kinematics solution in the Rover Sequencing and Visualization Program (RSVP. This method, with the proper wheel slip and sliding factors, produces accurate simulation of the Mars Exploration rovers, which have been validated with the earth-testing vehicle. This computational technique has been deployed to the operation of the MER rovers in the extended mission period. Particularly, it yields high quality prediction of the rover motion on high slope areas. The simulated path of the rovers has been validated using the telemetry from the onboard Visual Odometry (VisOdom. Preliminary results indicate that the proposed simulation is very effective in planning the path of the rovers on the high-slope areas.

  9. Identification and replication of prediction models for ovulation, pregnancy and live birth in infertile women with polycystic ovary syndrome.

    Science.gov (United States)

    Kuang, Hongying; Jin, Susan; Hansen, Karl R; Diamond, Michael P; Coutifaris, Christos; Casson, Peter; Christman, Gregory; Alvero, Ruben; Huang, Hao; Bates, G Wright; Usadi, Rebecca; Lucidi, Scott; Baker, Valerie; Santoro, Nanette; Eisenberg, Esther; Legro, Richard S; Zhang, Heping

    2015-09-01

    large sample sizes. Younger age, lower baseline free androgen index and insulin, shorter duration of attempting conception, and higher baseline sex hormone-binding globulin significantly predicted at least one pregnancy outcome. The ROC curves (with AUCs of 0.66-0.76) and calibration plots and chi-square tests indicated stable predictive power of the identified variables (P-values ≥0.07 for all goodness-of-fit and validation tests). This is a secondary analysis. Although our primary objective was to confirm previously reported results and identify new predictors of ovulation and pregnancy outcomes among PPCOS-II participants, our approach is exploratory and warrants further replication. We have largely confirmed the predictors that were identified in the PPCOS-I trial. However, we have also revealed new predictors, particularly the role of smoking. While a history of ever smoking was not a significant predictor for live birth, a closer look at current, quit, and never smoking revealed that current smoking was a significant risk factor. The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Grants U10 HD27049, U10 HD38992, U10HD055925, U10 HD39005, U10 HD33172, U10 HD38998, U10 HD055936, U10 HD055942, and U10 HD055944; and U54-HD29834. Heilongjiang University of Chinese Medicine Grants 051277 and B201005. R.S.L. reports receiving consulting fees from Euroscreen, AstraZeneca, Clarus Therapeutics, and Takeda, and grant support from Ferring, Astra Zeneca, and Toba. K.R.H. reports receiving grant support from Roche Diagnostics and Ferring Pharmascience. G.C. reports receiving Honorarium and grant support from Abbvie Pharmaceuticals and Bayer Pharmaceuticals. M.P.D. holds equity from Advanced Reproductive Care Inc. and DS Biotech, receives fees from Advanced Reproductive Care Inc., Actamax, Auxogyn, ZSX Medical, Halt Medical, and Neomed, and receives grant support from Boehringer-Ingelheim, Abbott, and BioSante, Ferring Pharmaceuticals

  10. The Dutch Claustrophobia Questionnaire: psychometric properties and predictive validity.

    Science.gov (United States)

    Van Diest, Ilse; Smits, Dirk; Decremer, Davina; Maes, Lori; Claes, Laurence

    2010-10-01

    Fear of suffocation and fear of restriction are thought to underlie claustrophobia and can be assessed with the Claustrophobia Questionnaire (CLQ; Radomsky et al., 2001). A first study tested the psychometric properties of a Dutch version of the CLQ. Students (N=363) completed a Dutch translation of the CLQ and a set of other questionnaires assessing other specific fears, anxiety or depression. Results confirmed the two-factor structure and showed that the Dutch version of the CLQ has good psychometric properties. A second study tested the predictive validity of the Dutch CLQ. Participants (N=23) were exposed each to nine claustrophobic situations with elements of suffocation, restriction or both. The Dutch CLQ was found to be a significant predictor of fear and respiratory reactivity during claustrophobic exposure. It can be concluded that the Dutch version of the CLQ is a reliable and valid instrument to assess claustrophobic fear. Copyright 2010 Elsevier Ltd. All rights reserved.

  11. The increasing predictive validity of self-rated health.

    Directory of Open Access Journals (Sweden)

    Jason Schnittker

    Full Text Available Using the 1980 to 2002 General Social Survey, a repeated cross-sectional study that has been linked to the National Death Index through 2008, this study examines the changing relationship between self-rated health and mortality. Research has established that self-rated health has exceptional predictive validity with respect to mortality, but this validity may be deteriorating in light of the rapid medicalization of seemingly superficial conditions and increasingly high expectations for good health. Yet the current study shows the validity of self-rated health is increasing over time. Individuals are apparently better at assessing their health in 2002 than they were in 1980 and, for this reason, the relationship between self-rated health and mortality is considerably stronger across all levels of self-rated health. Several potential mechanisms for this increase are explored. More schooling and more cognitive ability increase the predictive validity of self-rated health, but neither of these influences explains the growing association between self-rated health and mortality. The association is also invariant to changing causes of death, including a decline in accidental deaths, which are, by definition, unanticipated by the individual. Using data from the final two waves of data, we find suggestive evidence that exposure to more health information is the driving force, but we also show that the source of information is very important. For example, the relationship between self-rated health and mortality is smaller among those who use the internet to find health information than among those who do not.

  12. Development and ex post validation of prediction equations of corn energy values for growing pigs

    Directory of Open Access Journals (Sweden)

    Everardo Ayres Correia Ellery

    2015-06-01

    Full Text Available The aim of this study was to determine and validate prediction equations for digestible (DE and metabolizable energy (ME of corn for growing pigs. The prediction equations were developed based on data on the chemical composition, digestible and metabolizable energy of corn grain (30 samples evaluated in experiments in Embrapa Suínos e Aves, Brazil. The equations were evaluated using regression analysis, and adjusted R² was the criterion for selection of the best models. Two equations were tested for DE and ME, each. To validate the equations, 1 experiment with 2 assays was performed to determine the values of DE and ME of 5 corn cultivars. In each assay, we used 24 growing pigs with initial average weight of 54.21 ± 1.68 kg in complete randomized block design with 6 treatments and 4 replicates. Treatments consisted of a reference diet and 5 ration tests composed of 60% of the reference diet and 40% of corn (1 of the 5 cultivars. Based on the results of the metabolic experiment and predicted values obtained in the equations, the validation of the equations was conducted using the lowest prediction error (pe as a criterion for selection. The equations that produced the most accurate estimates of DE and ME of corn were as follows: DE = 11812 – 1015.9CP – 837.9EE – 1641ADF + 2616.3Ash + 47.5(CP2 + 114.7(CF2 + 46(ADF2 – 1.6(NDF2 – 997.1(Ash2 + 151.9EECF + 23.2EENDF – 126.4CPCF + 136.4CPADF – 4.0CPNDF, with R2 = 0.81 and pe = 2.33; ME = 12574 – 1254.9CP – 1140.5EE – 1359.9ADF + 2816.3Ash + 77.6(CP2 + 92.3(CF2 + 54.1(ADF2 – 1.8(NDF2 – 1097.2(Ash2 + 240.6EECF + 26.3EENDF – 157.4CPCF + 96.5CPADF – 4.4CPNDF, with R2 = 0.89 and pe = 2.24. Thus, using the data on chemical composition, it is possible to derive prediction equations for DE and ME of corn for pigs; these equations seem to be valid because of the small prediction errors suggestive of high accuracy of these models.

  13. Does Literacy Skill Level Predict Performance in Community College Courses: A Replication and Extension

    Science.gov (United States)

    Allen, Nancy J.; DeLauro, Kimberly A.; Perry, Julia K.; Carman, Carol A.

    2017-01-01

    Previous research has found a positive relationship between students who had completed a sequence of developmental reading and writing courses and success in a reading-intensive college-level course. This study replicates and expands upon the previous research of Goldstein and Perin (2008) by utilizing a differently diverse sample and an…

  14. Does Literacy Skill Level Predict Performance in Community College Courses: A Replication and Extension

    Science.gov (United States)

    Allen, Nancy J.; DeLauro, Kimberly A.; Perry, Julia K.; Carman, Carol A.

    2017-01-01

    Previous research has found a positive relationship between students who had completed a sequence of developmental reading and writing courses and success in a reading-intensive college-level course. This study replicates and expands upon the previous research of Goldstein and Perin (2008) by utilizing a differently diverse sample and an…

  15. Validation of ice loads predicted from meteorological models

    Energy Technology Data Exchange (ETDEWEB)

    Veal, A.; Skea, A. [UK Met Office, Exeter, England (United Kingdom); Wareing, B. [Brian Wareing Tech Ltd., England (United Kingdom)

    2005-07-01

    Results of a field trial conducted on 2 Gerber PVM-100 instruments at Deadwater Fell test site in the United Kingdom were presented. The trials were conducted to assess whether the instruments were capable of measuring the liquid water content of the air, as well as to validate an ice model in terms of accretion rates on different sized conductors. Ambient air temperature, wind speed and direction were monitored at the Deadwater Fell weather station along with load cell values. Time lapse video recorders and a web camera system were used to view the performance of the conductors in varying weather conditions. All data was collected and stored at the site. It was anticipated that output from the instruments could be related to the conditions under which overhead line conductors suffer from ice loads, and help to revise weather maps which have proved to be incompatible with utility experience and the lifetimes achieved by overhead line designs. The data provided from the Deadwater work included logged data from the Gerbers, weather data and load data from a 10 mm diameter aluminium alloy conductor. When the combination of temperature, wind direction and Gerber output indicated icing conditions, they were confirmed by the conductor's load cell data. The tests confirmed the validity of the Gerber instruments to predict the occurrence of icing conditions, when combined with other meteorological data. It was concluded that the instruments may aid in optimized prediction methods for ice loads and icing events. 2 refs., 4 figs.

  16. Predictive validities: figures of merit or veils of deception?

    Directory of Open Access Journals (Sweden)

    PETER H. SCHONEMANN

    2009-06-01

    Full Text Available The ETS has recently released new estimates of validities of the GRE for predicting cumulative graduate GPA. They average in the middle thirties – twice as high as those previously reported by a number of independent investigators.It is shown in the first part of this paper that this unexpected finding can be traced to a flawed methodology that tends to inflate multiple correlation estimates, especially those of populations values near zero.Secondly, the issue of upward corrections of validity estimates for restriction of range is taken up. It is shown that they depend on assumptions that are rarely met by the data. Finally, it is argued more generally that conventional test theory, which is couched in terms of correlations and variances, is not only unnecessarily abstract but, more importantly, incomplete, since the practical utility of a test does not only depend on its validity, but also on base-rates and admission quotas. A more direct and conclusive method for gauging the utility of a test involves misclassification rates, and entirely dispenses with questionable assumptions and post-hoc "corrections".On applying this approach to the GRE, it emerges (1 that the GRE discriminates against ethnic and economic minorities, and (2 that it often produces more erroneous decisions than a purely random admissions policy would.

  17. Predicting the ungauged basin: model validation and realism assessment

    Science.gov (United States)

    van Emmerik, Tim; Mulder, Gert; Eilander, Dirk; Piet, Marijn; Savenije, Hubert

    2016-04-01

    The hydrological decade on Predictions in Ungauged Basins (PUB) [1] led to many new insights in model development, calibration strategies, data acquisition and uncertainty analysis. Due to a limited amount of published studies on genuinely ungauged basins, model validation and realism assessment of model outcome has not been discussed to a great extent. With this study [2] we aim to contribute to the discussion on how one can determine the value and validity of a hydrological model developed for an ungauged basin. As in many cases no local, or even regional, data are available, alternative methods should be applied. Using a PUB case study in a genuinely ungauged basin in southern Cambodia, we give several examples of how one can use different types of soft data to improve model design, calibrate and validate the model, and assess the realism of the model output. A rainfall-runoff model was coupled to an irrigation reservoir, allowing the use of additional and unconventional data. The model was mainly forced with remote sensing data, and local knowledge was used to constrain the parameters. Model realism assessment was done using data from surveys. This resulted in a successful reconstruction of the reservoir dynamics, and revealed the different hydrological characteristics of the two topographical classes. We do not present a generic approach that can be transferred to other ungauged catchments, but we aim to show how clever model design and alternative data acquisition can result in a valuable hydrological model for ungauged catchments. [1] Sivapalan, M., Takeuchi, K., Franks, S., Gupta, V., Karambiri, H., Lakshmi, V., et al. (2003). IAHS decade on predictions in ungauged basins (PUB), 2003-2012: shaping an exciting future for the hydrological sciences. Hydrol. Sci. J. 48, 857-880. doi: 10.1623/hysj.48.6.857.51421 [2] van Emmerik, T., Mulder, G., Eilander, D., Piet, M. and Savenije, H. (2015). Predicting the ungauged basin: model validation and realism assessment

  18. Anthropometric dependence of the response of a thorax FE model under high speed loading: validation and real world accident replication.

    Science.gov (United States)

    Roth, Sébastien; Torres, Fabien; Feuerstein, Philippe; Thoral-Pierre, Karine

    2013-05-01

    Finite element analysis is frequently used in several fields such as automotive simulations or biomechanics. It helps researchers and engineers to understand the mechanical behaviour of complex structures. The development of computer science brought the possibility to develop realistic computational models which can behave like physical ones, avoiding the difficulties and costs of experimental tests. In the framework of biomechanics, lots of FE models have been developed in the last few decades, enabling the investigation of the behaviour of the human body submitted to heavy damage such as in road traffic accidents or in ballistic impact. In both cases, the thorax/abdomen/pelvis system is frequently injured. The understanding of the behaviour of this complex system is of extreme importance. In order to explore the dynamic response of this system to impact loading, a finite element model of the human thorax/abdomen/pelvis system has, therefore, been developed including the main organs: heart, lungs, kidneys, liver, spleen, the skeleton (with vertebrae, intervertebral discs, ribs), stomach, intestines, muscles, and skin. The FE model is based on a 3D reconstruction, which has been made from medical records of anonymous patients, who have had medical scans with no relation to the present study. Several scans have been analyzed, and specific attention has been paid to the anthropometry of the reconstructed model, which can be considered as a 50th percentile male model. The biometric parameters and laws have been implemented in the dynamic FE code (Radioss, Altair Hyperworks 11©) used for dynamic simulations. Then the 50th percentile model was validated against experimental data available in the literature, in terms of deflection, force, whose curve must be in experimental corridors. However, for other anthropometries (small male or large male models) question about the validation and results of numerical accident replications can be raised.

  19. Exploring the clinical validity of predicted TRE in navigation

    Science.gov (United States)

    Bickel, M.; Güler, Ö.; Kral, F.; Schwarm, F.; Freysinger, W.

    2010-02-01

    In a detailed laboratory investigation we performed a series of experiments in order to assess the validity of the widely used TRE concept to predict the application accuracy. On base of 1mm CT scan a plastic skull, a cadaver head and a volunteer were registered to an in house navigation system. We stored the position data of an optical camera (NDI Polaris) for registration with pre-defined CT coordinates. For every specimen we choose 3, 5, 7 and 9 registration and 10 evaluation points, respectively, performing 10 registrations. The data were evaluated both with the Arun and the Horn approaches. The vectorial difference between actual and predefined position in the CT data set was stored and evaluated for FRE and TRE. Evaluation and visualization was implemented in Matlab. The data were analyzed, specifically for normal distribution, with MS Excel and SPSS Version 15.0. For the plastic skull and the anatomic specimen submillimetric application accuracy was found experimentally and confirmed by the calculated TRE. Since for the volunteer no Titanium screws were implanted anatomic landmarks had to be used for registration and evaluation; an application accuracy in the low millimeter regime was found in all approaches. However, the detailed statistical analysis of the data revealed that the model predictions and the actual measurements do not exhibit a strong statistical correlation (p < 0.05). These data suggest that the TRE predictions are too optimistic and should be used with caution intraoperatively.

  20. Lightweight ZERODUR: Validation of Mirror Performance and Mirror Modeling Predictions

    Science.gov (United States)

    Hull, Tony; Stahl, H. Philip; Westerhoff, Thomas; Valente, Martin; Brooks, Thomas; Eng, Ron

    2017-01-01

    Upcoming spaceborne missions, both moderate and large in scale, require extreme dimensional stability while relying both upon established lightweight mirror materials, and also upon accurate modeling methods to predict performance under varying boundary conditions. We describe tests, recently performed at NASA's XRCF chambers and laboratories in Huntsville Alabama, during which a 1.2 m diameter, f/1.2988% lightweighted SCHOTT lightweighted ZERODUR(TradeMark) mirror was tested for thermal stability under static loads in steps down to 230K. Test results are compared to model predictions, based upon recently published data on ZERODUR(TradeMark). In addition to monitoring the mirror surface for thermal perturbations in XRCF Thermal Vacuum tests, static load gravity deformations have been measured and compared to model predictions. Also the Modal Response(dynamic disturbance) was measured and compared to model. We will discuss the fabrication approach and optomechanical design of the ZERODUR(TradeMark) mirror substrate by SCHOTT, its optical preparation for test by Arizona Optical Systems (AOS). Summarize the outcome of NASA's XRCF tests and model validations

  1. Ray Tracing RF Field Prediction: An Unforgiving Validation

    Directory of Open Access Journals (Sweden)

    E. M. Vitucci

    2015-01-01

    Full Text Available The prediction of RF coverage in urban environments is now commonly considered a solved problem with tens of models proposed in the literature showing good performance against measurements. Among these, ray tracing is regarded as one of the most accurate ones available. In the present work, however, we show that a great deal of work is still needed to make ray tracing really unleash its potential in practical use. A very extensive validation of a state-of-the-art 3D ray tracing model is carried out through comparison with measurements in one of the most challenging environments: the city of San Francisco. Although the comparison is based on RF cellular coverage at 850 and 1900 MHz, a widely studied territory, very relevant sources of error and inaccuracy are identified in several cases along with possible solutions.

  2. Incremental validity of emotional intelligence ability in predicting academic achievement.

    Science.gov (United States)

    Lanciano, Tiziana; Curci, Antonietta

    2014-01-01

    We tested the incremental validity of an ability measure of emotional intelligence (El) in predicting academic achievement in undergraduate students, controlling for cognitive abilities and personality traits. Academic achievement has been conceptualized in terms of the number of exams, grade point average, and study time taken to prepare for each exam. Additionally, gender differences were taken into account in these relationships. Participants filled in the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT), the Raven's Advanced Progressive Matrices, the reduced version of the Eysenck Personality Questionnaire, and academic achievement measures. Results showed that El abilities were positively related to academic achievement indices, such as the number of exams and grade point average; total El ability and the Perceiving branch were negatively associated with the study time spent preparing for exams. Furthermore, El ability adds a percentage of incremental variance with respect to cognitive ability and personality variables in explaining scholastic success. The magnitude of the associations between El abilities and academic achievement measures was generally higher for men than for women. Jointly considered, the present findings support the incremental validity of the MSCEIT and provide positive indications of the importance of El in students' academic development. The helpfulness of El training in the context of academic institutions is discussed.

  3. DNAskew:Statistical Analysis of Base Compositional Asymmetry and Prediction of Replication Boundaries in the Genome Sequences

    Institute of Scientific and Technical Information of China (English)

    Xiang-Ru MA; Shao-Bo XIAO; Ai-Zhen GUO; Jian-Qiang L(U); Huan-Chun CHEN

    2004-01-01

    Sueoka and Lobry declared respectively that, in the absence of bias between the two DNA strands for mutation and selection, the base composition within each strand should be A=T and C=G (this state is called Parity Rule type 2, PR2). However, the genome sequences of many bacteria, vertebrates and viruses showed asymmetries in base composition and gene direction. To determine the relationship of base composition skews with replication orientation, gene function, codon usage biases and phylogenetic evolution,in this paper a program called DNAskew was developed for the statistical analysis of strand asymmetry and codon composition bias in the DNA sequence. In addition, the program can also be used to predict the replication boundaries of genome sequences. The method builds on the fact that there are compositional asymmetries between the leading and the lagging strand for replication. DNAskew was written in Perl script language and implemented on the LINUX operating system. It works quickly with annotated or unannotated sequences in GBFF (GenBank flatfile) or fasta format. The source code is freely available for academic use at http://www.epizooty.com/pub/stat/DNAskew.

  4. Prediction and validation of hemodialysis duration in acute methanol poisoning.

    Science.gov (United States)

    Lachance, Philippe; Mac-Way, Fabrice; Desmeules, Simon; De Serres, Sacha A; Julien, Anne-Sophie; Douville, Pierre; Ghannoum, Marc; Agharazii, Mohsen

    2015-11-01

    The duration of hemodialysis (HD) in methanol poisoning (MP) is dependent on the methanol concentration, the operational parameters used during HD, and the presence and severity of metabolic acidosis. However, methanol assays are not easily available, potentially leading to undue extension or premature termination of treatment. Here we provide a prediction model for the duration of high-efficiency HD in MP. In a retrospective cohort study, we identified 71 episodes of MP in 55 individuals who were treated with alcohol dehydrogenase inhibition and HD. Four patients had residual visual abnormality at discharge and only one patient died. In 46 unique episodes of MP with high-efficiency HD the mean methanol elimination half-life (T1/2) during HD was 108 min in women, significantly different from the 129 min in men. In a training set of 28 patients with MP, using the 90th percentile of gender-specific elimination T1/2 (147 min in men and 141 min in women) and a target methanol concentration of 4 mmol/l allowed all cases to reach a safe methanol of under 6 mmol/l. The prediction model was confirmed in a validation set of 18 patients with MP. High-efficiency HD time in hours can be estimated using 3.390 × (Ln (MCi/4)) for women and 3.534 × (Ln (MCi/4)) for men, where MCi is the initial methanol concentration in mmol/l, provided that metabolic acidosis is corrected.

  5. Validation of resting metabolic rate prediction equations for teenagers

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Santos da Fonseca

    2007-09-01

    Full Text Available The resting metabolic rate (RMR can be defi ned as the minimum rate of energy spent and represents the main component of the energetic outlay. The purpose of this study is to validate equations to predict the resting metabolic rate in teenagers (103 individuals, being 51 girls and 52 boys, with age between 10 and 17 years from Florianópolis – SC – Brazil. It was measured: the body weight, body height, skinfolds and obtained the lean and body fat mass through bioimpedance. The nonproteic RMR was measured by Weir’s equation (1949, utilizing AeroSport TEEM-100 gas analyzer. The studied equations were: Harry and Benedict (1919, Schofi eld (1985, WHO/FAO/UNU (1985, Henry and Rees (1991, Molnár et al. (1998, Tverskaya et al. (1998 and Müller et al. (2004. In order to study the cross-validation of the RMR prediction equations and its standard measure (Weir 1949, the following statistics procedure were calculated: Pearson’s correlation (r ≥ 0.70, the “t” test with the signifi cance level of p0.05 in relation to the standard measure, with exception of the equations suggested for Tverskaya et al. (1998, and the two models of Müller et al (2004. Even though there was not a signifi cant difference, only the models considered for Henry and Rees (1991, and Molnár et al. (1995 had gotten constant error variation under 5%. All the equations analyzed in the study in girls had not reached criterion of correlation values of 0.70 with the indirect calorimetry. Analyzing the prediction equations of RMR in boys, all of them had moderate correlation coeffi cients with the indirect calorimetry, however below 0.70. Only the equation developed for Tverskaya et al. (1998 presented differences (p ABSTRACT0,05 em relação à medida padrão (Weir 1949, com exceção das equações sugeridas por Tverskaya et al. (1998 e os dois modelos de Müller et al (2004. Mesmo não havendo diferença signifi cativa, somente os modelos propostos por Henry e Rees (1991

  6. Discovery and replication of a peripheral tissue DNA methylation biosignature to augment a suicide prediction model

    NARCIS (Netherlands)

    Clive, Makena L; Boks, Marco P; Vinkers, Christiaan H; Osborne, Lauren M; Payne, Jennifer L; Ressler, Kerry J; Smith, Alicia K; Wilcox, Holly C; Kaminsky, Zachary

    2016-01-01

    BACKGROUND: Suicide is the second leading cause of death among adolescents in the USA, and rates are rising. Methods to identify individuals at risk are essential for implementing prevention strategies, and the development of a biomarker can potentially improve prediction of suicidal behaviors. Pred

  7. Simple clinical variables predict liver histology in hepatitis C: prospective validation of a clinical prediction model.

    Science.gov (United States)

    Romagnuolo, Joseph; Andrews, Christopher N; Bain, Vincent G; Bonacini, Maurizio; Cotler, Scott J; Ma, Mang; Sherman, Morris

    2005-11-01

    A recent single-center multivariate analysis of hepatitis C (HCV) patients showed that having any two criteria: 1) ferritin > or =200 microg/l and 2) spider nevi and/or albumin clinical prediction model using an independent multicenter sample. Eighty-one patients with previously untreated active chronic HCV underwent physical examination, laboratory investigation, and liver biopsy. Biopsies were read, in blinded fashion, by a single pathologist, using a modified Hytiroglou (1995) scale. The clinical scoring system was correlated with histology; likelihood ratios (LRs), Fisher's exact p-values, and receiver operating characteristics (ROCs) were calculated. Data recording was complete in 77 and 38 patients regarding fibrotic stage and inflammatory grade, respectively. For fibrosis, 3/3 patients with any three criteria (LR 17, positive predictive value (PPV) 100%), 4/5 patients with any two criteria (LR 5.1), and 15/47 with no criteria (LR 0.6, negative predictive value (NPV) 68%) had stage 2 or greater fibrosis on biopsy (p=0.01). For inflammation, 5/5 patients with both criteria (LR 15, PPV 100%), and 8/19 patients with no criteria (LR 0.5, NPV 58%) had moderate-severe inflammation on liver biopsy (p=0.036). When missing variables were assumed to be normal, recalculated LRs were almost identical. An alanine aminotransferase (ALAT) level data set has validated our published model which uses simple clinical variables accurately and significantly to predict hepatic fibrosis and inflammation in HCV patients.

  8. Tsunami-HySEA model validation for tsunami current predictions

    Science.gov (United States)

    Macías, Jorge; Castro, Manuel J.; González-Vida, José Manuel; Ortega, Sergio

    2016-04-01

    Model ability to compute and predict tsunami flow velocities is of importance in risk assessment and hazard mitigation. Substantial damage can be produced by high velocity flows, particularly in harbors and bays, even when the wave height is small. Besides, an accurate simulation of tsunami flow velocities and accelerations is fundamental for advancing in the study of tsunami sediment transport. These considerations made the National Tsunami Hazard Mitigation Program (NTHMP) proposing a benchmark exercise focussed on modeling and simulating tsunami currents. Until recently, few direct measurements of tsunami velocities were available to compare and to validate model results. After Tohoku 2011 many current meters measurement were made, mainly in harbors and channels. In this work we present a part of the contribution made by the EDANYA group from the University of Malaga to the NTHMP workshop organized at Portland (USA), 9-10 of February 2015. We have selected three out of the five proposed benchmark problems. Two of them consist in real observed data from the Tohoku 2011 event, one at Hilo Habour (Hawaii) and the other at Tauranga Bay (New Zealand). The third one consists in laboratory experimental data for the inundation of Seaside City in Oregon. Acknowledgements: This research has been partially supported by the Junta de Andalucía research project TESELA (P11-RNM7069) and the Spanish Government Research project DAIFLUID (MTM2012-38383-C02-01) and Universidad de Málaga, Campus de Excelencia Andalucía TECH. The GPU and multi-GPU computations were performed at the Unit of Numerical Methods (UNM) of the Research Support Central Services (SCAI) of the University of Malaga.

  9. A Study on the Predictive Validity of Reading Comprehension Part in the Simulated NMET

    Institute of Scientific and Technical Information of China (English)

    张丽昕

    2013-01-01

    Reading comprehension test occupies nearly one third of the total NMET (National Matriculation English Test) mark. The simulated NMET is designed in accordance with the requirements of the NMET to find out learning weakness, predict their per⁃formance on the NMET and make sufficient preparation for the NMET. Predictive validity is used to explore the predictive degree of language testing. On the basis of theories on predictive validity, this study tries to investigate the predictive validity of reading comprehension part in the simulated NMET and hopes to exert positive influence on senior three English teaching.

  10. Microcomputer-based tests for repeated-measures: Metric properties and predictive validities

    Science.gov (United States)

    Kennedy, Robert S.; Baltzley, Dennis R.; Dunlap, William P.; Wilkes, Robert L.; Kuntz, Lois-Ann

    1989-01-01

    A menu of psychomotor and mental acuity tests were refined. Field applications of such a battery are, for example, a study of the effects of toxic agents or exotic environments on performance readiness, or the determination of fitness for duty. The key requirement of these tasks is that they be suitable for repeated-measures applications, and so questions of stability and reliability are a continuing, central focus of this work. After the initial (practice) session, seven replications of 14 microcomputer-based performance tests (32 measures) were completed by 37 subjects. Each test in the battery had previously been shown to stabilize in less than five 90-second administrations and to possess retest reliabilities greater than r = 0.707 for three minutes of testing. However, all the tests had never been administered together as a battery and they had never been self-administered. In order to provide predictive validity for intelligence measurement, the Wechsler Adult Intelligence Scale-Revised and the Wonderlic Personnel Test were obtained on the same subjects.

  11. Short communication : Validation of genomic breeding value predictions for feed intake and feed efficiency traits

    NARCIS (Netherlands)

    Pryce, J.E.; Wales, W.J.; Haas, de Y.; Veerkamp, R.F.; Hayes, B.J.; Coffey, M.P.; Marett, L.C.; Bornhill, J.B.; Gonzalez-Recio, O.

    2014-01-01

    Validating genomic prediction equations in independent populations is an important part of evaluating genomic selection. Published genomic predictions from 2 studies on (1) residual feed intake and (2) dry matter intake (DMI) were validated in a cohort of 78 multiparous Holsteins from Australia. The

  12. Predictive Validity of DSM-IV Oppositional Defiant and Conduct Disorders in Clinically Referred Preschoolers

    Science.gov (United States)

    Keenan, Kate; Boeldt, Debra; Chen, Diane; Coyne, Claire; Donald, Radiah; Duax, Jeanne; Hart, Katherine; Perrott, Jennifer; Strickland, Jennifer; Danis, Barbara; Hill, Carri; Davis, Shante; Kampani, Smita; Humphries, Marisha

    2011-01-01

    Background: Diagnostic validity of oppositional defiant and conduct disorders (ODD and CD) for preschoolers has been questioned based on concerns regarding the ability to differentiate normative, transient disruptive behavior from clinical symptoms. Data on concurrent validity have accumulated, but predictive validity is limited. Predictive…

  13. Brief implicit association test: Validity and utility in prediction of voting behavior

    Directory of Open Access Journals (Sweden)

    Pavlović Maša D.

    2013-01-01

    Full Text Available We employed the Brief Implicit Association Test (a recently developed short version of IAT to measure implicit political attitudes toward four political parties running for Serbian parliament. To test its criterion validity, we measured voting intention and actual voting behavior. In addition, we introduced political involvement as a potential moderator of the BIAT’s predictive and incremental validity. The BIAT demonstrated good internal and predictive validity, but lacked incremental validity over self-report measures. Predictive power of the BIAT was moderated by political involvement - the BIAT scores were stronger predictors of voting intention and behavior among voters highly involved in politics. [Projekat Ministarstva nauke Republike Srbije, br. 179018

  14. Validation of stress prediction during solidification of cast components

    CSIR Research Space (South Africa)

    Paine, AP

    2007-07-01

    Full Text Available designed box shaped experimental casting was used to validate the commercial finite-element code ProCAST (casting simulation software), with respect to distortions as well as residual stresses....

  15. A popularity prediction and dynamic data replication study for the ATLAS distributed data management

    CERN Document Server

    Beermann, Thomas

    ATLAS (A Toroidal LHC Apparatus) is one of several experiments of at the Large Hadron Collider (LHC) at CERN in Geneva, Switzerland. The LHC is the largest and most powerful particle accelerator in the world, which is able to operate at unprecedented energy levels. Because of this, ATLAS is able to observe physical phenomena and massive particles that were not observable before. The detectors at the LHC itself create vast amount of data that need to be accessible to physicists for their analysis. For this reason a worldwide computing grid (WLCG) was created that connects hundreds of computing centres across the planet. The experiments constantly create new data but older data has to be kept as well. The available resources are limited, which requires a smart management of the storage space. This thesis presents a method to dynamically create new replicas and delete unused replicas based on a prediction of data popularity to improve user waiting times. The first part gives an general introduction of the LHC, A...

  16. How job demands, resources, and burnout predict objective performance: a constructive replication.

    Science.gov (United States)

    Bakker, Arnold B; Van Emmerik, Hetty; Van Riet, Pim

    2008-07-01

    The present study uses the Job Demands-Resources model (Bakker & Demerouti, 2007) to examine how job characteristics and burnout (exhaustion and cynicism) contribute to explaining variance in objective team performance. A central assumption in the model is that working characteristics evoke two psychologically different processes. In the first process, job demands lead to constant psychological overtaxing and in the long run to exhaustion. In the second process, a lack of job resources precludes actual goal accomplishment, leading to cynicism. In the present study these two processes were used to predict objective team performance. A total of 176 employees from a temporary employment agency completed questionnaires on job characteristics and burnout. These self-reports were linked to information from the company's management information system about teams' (N=71) objective sales performance (actual sales divided by the stated objectives) during the 3 months after the questionnaire data collection period. The results of structural equation modeling analyses did not support the hypothesis that exhaustion mediates the relationship between job demands and performance, but confirmed that cynicism mediates the relationship between job resources and performance suggesting that work conditions influence performance particularly through the attitudinal component of burnout.

  17. Verification, validation, and predictive capability in computational engineering and physics.

    Energy Technology Data Exchange (ETDEWEB)

    Oberkampf, William Louis; Hirsch, Charles (Vrije Universiteit Brussel, Brussels, Belgium); Trucano, Timothy Guy

    2003-02-01

    Developers of computer codes, analysts who use the codes, and decision makers who rely on the results of the analyses face a critical question: How should confidence in modeling and simulation be critically assessed? Verification and validation (V&V) of computational simulations are the primary methods for building and quantifying this confidence. Briefly, verification is the assessment of the accuracy of the solution to a computational model. Validation is the assessment of the accuracy of a computational simulation by comparison with experimental data. In verification, the relationship of the simulation to the real world is not an issue. In validation, the relationship between computation and the real world, i.e., experimental data, is the issue.

  18. Replication, falsification, and the crisis of confidence in social psychology

    Directory of Open Access Journals (Sweden)

    Brian D. Earp

    2015-05-01

    Full Text Available The (latest crisis in confidence in social psychology has generated much heated discussion about the importance of replication, including how such replication should be carried out as well as interpreted by scholars in the field. What does it mean if a replication attempt fails—does it mean that the original results, or the theory that predicted them, have been falsified? And how should failed replications affect our belief in the validity of the original research? In this paper, we consider the replication debate from a historical and philosophical perspective, and provide a conceptual analysis of both replication and falsification as they pertain to this important discussion. Along the way, we introduce a Bayesian framework for assessing failed replications in terms of how they should affect our confidence in purported findings.

  19. Replication, falsification, and the crisis of confidence in social psychology.

    Science.gov (United States)

    Earp, Brian D; Trafimow, David

    2015-01-01

    The (latest) crisis in confidence in social psychology has generated much heated discussion about the importance of replication, including how it should be carried out as well as interpreted by scholars in the field. For example, what does it mean if a replication attempt "fails"-does it mean that the original results, or the theory that predicted them, have been falsified? And how should "failed" replications affect our belief in the validity of the original research? In this paper, we consider the replication debate from a historical and philosophical perspective, and provide a conceptual analysis of both replication and falsification as they pertain to this important discussion. Along the way, we highlight the importance of auxiliary assumptions (for both testing theories and attempting replications), and introduce a Bayesian framework for assessing "failed" replications in terms of how they should affect our confidence in original findings.

  20. Replication, falsification, and the crisis of confidence in social psychology

    Science.gov (United States)

    Earp, Brian D.; Trafimow, David

    2015-01-01

    The (latest) crisis in confidence in social psychology has generated much heated discussion about the importance of replication, including how it should be carried out as well as interpreted by scholars in the field. For example, what does it mean if a replication attempt “fails”—does it mean that the original results, or the theory that predicted them, have been falsified? And how should “failed” replications affect our belief in the validity of the original research? In this paper, we consider the replication debate from a historical and philosophical perspective, and provide a conceptual analysis of both replication and falsification as they pertain to this important discussion. Along the way, we highlight the importance of auxiliary assumptions (for both testing theories and attempting replications), and introduce a Bayesian framework for assessing “failed” replications in terms of how they should affect our confidence in original findings. PMID:26042061

  1. Testing for the Factorial Validity, Replication, and Invariance of a Measuring Instrument: A Paradigmatic Application Based on the Maslach Burnout Inventory.

    Science.gov (United States)

    Byrne, B M

    1994-07-01

    The intent of this article is twofold: (a) to report substantive findings from a cross-validated study that tested for the factorial validity and invariance of the Maslach Burnout Inventory (MBI) across gender for elementary (males n = 742; females n = 801) and secondary (males n = 659; females n = 721) teachers, and (b) for purposes of helping readers who may be new to the structural modeling methodology, to provide an example of how these procedures may be applied in testing for the construct validity of a measuring instrument. Unique to this article is the use of multiple model-fitting criteria that address issues related to nonnormality of the data, complexity and replicability of the model, and error of approximation and sampling error in the estimation of fit; other "experimental" indices of fit are also included. Substantively, although results argue generally for the equivalency of the MBI across gender, calibration/validation groups, and teaching panels, they also suggest the need for a reexamination of content and retesting of construct validity related to six of the 22 items.

  2. The Incremental Validity of Positive Emotions in Predicting School Functioning

    Science.gov (United States)

    Lewis, Ashley D.; Huebner, E. Scott; Reschly, Amy L.; Valois, Robert F.

    2009-01-01

    Proponents of positive psychology have argued for more comprehensive assessments incorporating positive measures (e.g., student strengths) as well as negative measures (e.g., psychological symptoms). However, few variable-centered studies have addressed the incremental validity of positive assessment data. The authors investigated the incremental…

  3. Validation of a method to predict hammer speed from cable force

    Directory of Open Access Journals (Sweden)

    Sara M. Brice

    2015-09-01

    Conclusion: This study successfully derived and validated a method that allows prediction of linear hammer speed from directly measured cable force data. Two linear regression models were developed and it was found that either model would be capable of predicting accurate speeds. However, data predicted using the shifted regression model were more accurate.

  4. The construct validity and predictive validity of a self-efficacy measure for student teachers in competence-based education

    NARCIS (Netherlands)

    Dinther, van M.; Dochy, P.; Segers, M.; Braeken, J.

    2013-01-01

    This study intends to investigate the validity of a self-efficacy measure which is developed for predictive and diagnostic purposes concerning student teachers in competence-based education. CFA results delivered converging evidence for the multidimensionality of the student teacher self-efficacy

  5. The construct validity and predictive validity of a self-efficacy measure for student teachers in competence-based education

    NARCIS (Netherlands)

    Dinther, van M.; Dochy, P.; Segers, M.; Braeken, J.

    2013-01-01

    This study intends to investigate the validity of a self-efficacy measure which is developed for predictive and diagnostic purposes concerning student teachers in competence-based education. CFA results delivered converging evidence for the multidimensionality of the student teacher self-efficacy co

  6. The predictive and external validity of the STarT Back Tool in Danish primary care

    DEFF Research Database (Denmark)

    Morsø, Lars; Kent, Peter; Albert, Hanne B;

    2013-01-01

    PURPOSE: The STarT Back Tool (SBT) was recently translated into Danish and its concurrent validity described. This study tested the predictive validity of the Danish SBT. METHODS: Danish primary care patients (n = 344) were compared to a UK cohort. SBT subgroup validity for predicting high activity...... limitation at 3 months' follow-up was assessed using descriptive proportions, relative risks, AUC and odds ratios. RESULTS: The SBT had a statistically similar predictive ability in Danish primary care as in UK primary care. Unadjusted relative risks for poor clinical outcome on activity limitation...

  7. Validation of an internal hardwood log defect prediction model

    Science.gov (United States)

    R. Edward. Thomas

    2011-01-01

    The type, size, and location of internal defects dictate the grade and value of lumber sawn from hardwood logs. However, acquiring internal defect knowledge with x-ray/computed-tomography or magnetic-resonance imaging technology can be expensive both in time and cost. An alternative approach uses prediction models based on correlations among external defect indicators...

  8. The validity of physical aggression in predicting adolescent academic performance.

    Science.gov (United States)

    Loveland, James M; Lounsbury, John W; Welsh, Deborah; Buboltz, Walter C

    2007-03-01

    Aggression has a long history in academic research as both a criterion and a predictor variable and it is well documented that aggression is related to a variety of poor academic outcomes such as: lowered academic performance, absenteeism and lower graduation rates. However, recent research has implicated physical aggression as being predictive of lower academic performance. The purpose of this study was to examine the role of the 'Big Five' personality traits of agreeableness, openness to experience, conscientiousness, neuroticism and extraversion and physical aggression in predicting the grade point averages (GPA) of adolescent students and to investigate whether or not there were differences in these relationships between male and female students. A sample of 992 students in grades 9 to 12 from a high school in south-eastern USA as part of a larger study examining the students' preparation for entry into the workforce. The study was correlational in nature: students completed a personality inventory developed by the second author with the GPA information supplied by the school. Results indicated that physical aggression accounts for 16% of variance in GPA and it adds 7% to the prediction of GPA beyond the Big Five. The Big Five traits added only 1.5% to the prediction of GPA after controlling for physical aggression. Interestingly, a significantly larger amount of variance in GPA was predicted by physical aggression for females than for males. Aggression accounts for significantly more variance in the GPA of females than for males, even when controlling for the Big Five personality factors. Future research should examine the differences in the expression of aggression in males and females, as well as how this is affecting interactions between peers and between students and their teachers.

  9. Response character styles in adolescents: a replication of convergent validity between the MMPI-A and the Rorschach.

    Science.gov (United States)

    Stokes, John M; Pogge, David L; Zaccario, Michele

    2013-01-01

    This study explored the extent to which similar or discordant response character styles (RCS) affected convergence between MMPI-A and Rorschach findings in a sample of 673 adolescents from a psychiatric inpatient setting. Meyer's (Meyer, 1997; Meyer, Riethmiller, Brooks, Benoit, & Handler, 2000) findings for adult samples were generally replicated in that adolescents showing similar RCS across both measures showed moderate to strong relationships between Rorschach and MMPI-A indicants of affective distress, psychosis, and interpersonal wariness, whereas those showing discordant RCS demonstrated negligible or negative correlations between these indicants. This pattern was evident for conceptually similar, but not conceptually unrelated variable pairs. Similarity and discordance of RCS was also found to have an impact on relationships with external criterion variables, including therapist ratings and discharge diagnoses. Moderated regression analysis supports the hypothesis that RCS moderates the strength of the relationship between Rorschach and MMPI-A. Implications for practice and future research are discussed.

  10. Validating a Hazardous Drinking Index in a Sample of Sexual Minority Women: Reliability, Validity and Predictive Accuracy

    Science.gov (United States)

    Riley, Barth B.; Hughes, Tonda L.; Wilsnack, Sharon C.; Johnson, Timothy P.; Benson, Perry; Aranda, Frances

    2017-01-01

    Background Although sexual minority women (SMW) are at increased risk of hazardous drinking (HD), efforts to validate HD measures have yet to focus on this population. Objectives Validation of a 13-item Hazardous Drinking Index (HDI) in a large sample of SMW. Methods Data were from 700 adult SMW (age 18–82) enrolled in the Chicago Health and Life Experiences of Women study. Criterion measures included counts of depressive symptoms and post-traumatic stress disorder (PTSD) symptoms, average daily and 30-day ethanol consumption, risky sexual behavior, and Diagnostic and Statistical Manual (DSM-IV) measures of alcohol abuse/dependence. Analyses included assessment of internal consistency, construction of receiver operating characteristic (ROC) curves to predict alcohol abuse/dependence, and correlations between HDI and criterion measures. We compared the psychometric properties (diagnostic accuracy and correlates of hazardous drinking) of the HDI to the commonly used CAGE instrument. Results KR-20 reliability for the HDI was 0.80, compared to 0.74 for the CAGE. Predictive accuracy, as measured by the area under the receiver operating characteristic curve for alcohol abuse/dependence, was HDI: 0.89; CAGE: 0.84. The HDI evidenced the best predictive efficacy and tradeoff between sensitivity and specificity. Results supported the concurrent validity of the HDI measure. Conclusions The Hazardous Drinking Index is a reliable and valid measure of hazardous drinking for sexual minority women. PMID:27661289

  11. Convergent Validity with the BERS-2 Teacher Rating Scale and the Achenbach Teacher's Report Form: A Replication and Extension

    Science.gov (United States)

    Benner, Gregory J.; Beaudoin, Kathleen; Mooney, Paul; Uhing, Brad M.; Pierce, Corey D.

    2008-01-01

    In the present study, we sought to extend instrument validation research for a strength-based emotional and behavior rating scale, the "Teacher Rating Scale of the Behavior and Emotional Rating Scale-Second Edition" (BERS-2; Epstein, M. H. (2004). "Behavioral and emotional rating scale" (2nd ed.). Austin, TX: PRO-ED) through…

  12. Convergent Validity with the BERS-2 Teacher Rating Scale and the Achenbach Teacher's Report Form: A Replication and Extension

    Science.gov (United States)

    Benner, Gregory J.; Beaudoin, Kathleen; Mooney, Paul; Uhing, Brad M.; Pierce, Corey D.

    2008-01-01

    In the present study, we sought to extend instrument validation research for a strength-based emotional and behavior rating scale, the "Teacher Rating Scale of the Behavior and Emotional Rating Scale-Second Edition" (BERS-2; Epstein, M. H. (2004). "Behavioral and emotional rating scale" (2nd ed.). Austin, TX: PRO-ED) through…

  13. Prediction and Validation of Mars Pathfinder Hypersonic Aerodynamic Data Base

    Science.gov (United States)

    Gnoffo, Peter A.; Braun, Robert D.; Weilmuenster, K. James; Mitcheltree, Robert A.; Engelund, Walter C.; Powell, Richard W.

    1998-01-01

    Postflight analysis of the Mars Pathfinder hypersonic, continuum aerodynamic data base is presented. Measured data include accelerations along the body axis and axis normal directions. Comparisons of preflight simulation and measurements show good agreement. The prediction of two static instabilities associated with movement of the sonic line from the shoulder to the nose and back was confirmed by measured normal accelerations. Reconstruction of atmospheric density during entry has an uncertainty directly proportional to the uncertainty in the predicted axial coefficient. The sensitivity of the moment coefficient to freestream density, kinetic models and center-of-gravity location are examined to provide additional consistency checks of the simulation with flight data. The atmospheric density as derived from axial coefficient and measured axial accelerations falls within the range required for sonic line shift and static stability transition as independently determined from normal accelerations.

  14. Predictive Validity of Accommodated LSAT Scores. Technical Report. LSAC Research Report Series.

    Science.gov (United States)

    Thornton, Andrea E.; Reese, Lynda M.; Pashley, Peter J.; Dalessandro, Susan P.

    This study was undertaken to evaluate the predictive validity of the Law School Admission Test (LSAT) earned under accommodated testing conditions. Of special interest was the validity of scores obtained by test takers who were accommodated under nonstandard time conditions (i.e., accommodations that included extra testing time). Separate…

  15. Predictive validity of kindergarten assessments on handwriting readiness.

    Science.gov (United States)

    van Hartingsveldt, Margo J; Cup, Edith H C; Hendriks, Jan C M; de Vries, Liesbeth; de Groot, Imelda J M; Nijhuis-van der Sanden, Maria W G

    2014-10-16

    We investigated the predictive value of a new kindergarten assessment of handwriting readiness on handwriting performance in first grade as evaluated by the Systematic Screening for Handwriting Difficulties (Dutch abbreviation: SOS). The kindergarten assessment consisted of the Writing Readiness Inventory Tool In Context (WRITIC), the Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery™VMI) and the Nine-Hole Peg Test (9-HPT). The WRITIC evaluates in kindergarten children (aged 5-6 years) prewriting skills, the Beery™VMI and 9-HPT evaluate visual motor integration and fine-motor coordination, all elements important for handwriting readiness. In kindergarten, 109 children (55 boys; mean age 70 months, SD 4.8 months) were tested with the WRITIC, Beery™VMI and 9-HPT and one year later in first grade (mean age 85 months, SD 4.5 months) with the SOS. A multivariable linear mixed model was used to identify variables that independently predict outcomes in first grade (SOS): baseline scores on WRITIC-TP, Beery™VMI, 9-HPT, 'sustained attention,' 'gender,' 'age' and 'intervention' in the intermediate period. The results showed that WRITIC-TP, Beery™VMI, and 9-HPT, 'sustained attention,' 'gender' and 'intervention' had all predictive value on the handwriting outcome. Thereby WRITIC-TP was the main predictor for outcome of SOS-Quality, and Beery™VMI and 9-HPT were the main predictors of SOS-Speed. This kindergarten assessment of WRITIC-TP, Beery™VMI, and 9-HPT contributes to the detection of children at risk for developing handwriting problems.

  16. Performance Prediction and Validation: Data, Frameworks, and Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Tinnesand, Heidi

    2017-05-19

    Improving the predictability and reliability of wind power generation and operations will reduce costs and potentially establish a framework to attract new capital into the distributed wind sector, a key cost reduction requirement highlighted in results from the distributed wind future market assessment conducted with dWind. Quantifying and refining the accuracy of project performance estimates will also directly address several of the key challenges identified by industry stakeholders in 2015 as part of the distributed wind resource assessment workshop and be cross-cutting for several other facets of the distributed wind portfolio. This presentation covers the efforts undertaken in 2016 to address these topics.

  17. Reliability and predictive validity of the Food Technology Neophobia Scale.

    Science.gov (United States)

    Evans, G; Kermarrec, C; Sable, T; Cox, D N

    2010-04-01

    The recently developed Food Technology Neophobia Scale (FTNS) was further tested to assess scale reliability. On 2 occasions, 131 consumers responded to the FTNS, technologies descriptions and 'willingness to try' food technologies for 7 products. In the second session, they were offered foods to taste. 'Information seeking' was measured as a potential confounder of stability. The intra-class correlation was 0.86 and there was no difference between the FTNS scores (p>0.05). Correlations with 'willingness to try' novel technologies were -0.39 to -0.58. The FTNS is confirmed as a reliable and predictive measure of responses to novel food technologies.

  18. Establishing construct and predictive validity of the prison inmate inventory for use with female inmates.

    Science.gov (United States)

    Degiorgio, Lisa

    2015-02-01

    This study establishes the validity of the Prison Inmate Inventory for use among female inmates (N = 628). Contrast groups were used to establish construct validity; negative binomial regression analysis was used to confirm predictive validity. Female inmates who were arrested at a younger age demonstrated more severe problems with violence, antisocial traits, distress, adjustment to prison life, and judgment. Results from the negative binomial analysis revealed that inmate risk (low and severe) predicted expected counts of probation revocations, parole revocation, and escape attempts. Expected counts were not related to race/ethnicity in this sample. © The Author(s) 2013.

  19. Concurrent and predictive validity of an early language screening program.

    Science.gov (United States)

    Klee, T; Carson, D K; Gavin, W J; Hall, L; Kent, A; Reece, S

    1998-06-01

    The efficacy of screening 2-year-old children for language delay using a parent-report questionnaire was investigated in three studies. The Language Development Survey (Rescorla, 1989) was mailed to 650 families at the time of their child's second birthday. Fifty-three percent of the surveys received by parents were completed and returned. Screening outcomes were then compared, in double-blind fashion, with the results of comprehensive clinical evaluations at ages 2 (N = 64) and 3 (N = 36). Parents' report of the size of their children's expressive vocabularies was highly correlated with clinical language measures at age 2. Children who screened positive performed significantly poorer than children who screened negative on standardized language tests and on measures taken from spontaneous conversation. The screening program demonstrated excellent sensitivity and specificity for identifying language delay at age 2 but somewhat lower levels for predicting developmental status one year later.

  20. The criterion-related validity of personality measures for predicting GPA: a meta-analytic validity competition.

    Science.gov (United States)

    McAbee, Samuel T; Oswald, Frederick L

    2013-06-01

    Interest in the role of personality traits in predicting academic performance outcomes has steadily increased over the last several decades, enough to produce a number of meta-analyses that summarize this research (e.g., Poropat, 2009; Richardson, Abraham, & Bond, 2012). These previous meta-analyses combine a variety of alternative personality measures under the assumption that they all reflect the same personality traits and thus predict outcomes similarly. The current meta-analysis tests this assumption by comparing different personality measures when predicting postsecondary grade point average (GPA). The operational validities (r+) of 5 frequently used measures of the Big Five personality traits were compared: the NEO Personality Inventory--Revised (NEO-PI-R; Costa & McCrae, 1992), the NEO Five-Factor Inventory (NEO-FFI; Costa & McCrae, 1992), the Big Five Inventory (BFI; e.g., Benet-Martínez & John, 1998), Goldberg's (1992) unipolar Big Five Factor Markers (Markers), and the Big Five International Personality Item Pool (IPIP; Goldberg, 1999). A systematic review of the psychological literature from 1992 to 2012 was conducted, identifying 51 studies containing 274 correlations. Conscientiousness demonstrated the strongest criterion-related validity for predicting GPA (r+ = .23), consistent with previous meta-analyses; in addition, this overall validity was found to be robust across measures (r(BFI)(+) = .24, r(IPIP)(+) = .21, r(Markers)(+) = .15, r(NEO-FFI)(+) = .24, r(NEO-PI-R)(+) = .26). Although the criterion-related validities for Extraversion, Agreeableness, Neuroticism, and Openness to Experience (Intellect) differed by measure, they were generally low (r+s < .10). Practical implications of the findings and directions for future research are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  1. Experimental validation of the twins prediction program for rolling noise. Pt.2: results

    NARCIS (Netherlands)

    Thompson, D.J.; Fodiman, P.; Mahé, H.

    1996-01-01

    Two extensive measurement campaigns have been carried out to validate the TWINS prediction program for rolling noise, as described in part 1 of this paper. This second part presents the experimental results of vibration and noise during train pass-bys and compares them with predictions from the TWIN

  2. Resolving Contradictions of Predictive Validity of University Matriculation Examinations in Nigeria: A Meta-Analysis Approach

    Science.gov (United States)

    Modupe, Ale Veronica; Babafemi, Kolawole Emmanuel

    2015-01-01

    The study examined the various means of solving contradictions of predictive studies of University Matriculation Examination in Nigeria. The study used a sample size of 35 studies on predictive validity of University Matriculation Examination in Nigeria, which was purposively selected to have met the criteria for meta-analysis. Two null hypotheses…

  3. Experimental validation of the twins prediction program for rolling noise. Pt.2: results

    NARCIS (Netherlands)

    Thompson, D.J.; Fodiman, P.; Mahé, H.

    1996-01-01

    Two extensive measurement campaigns have been carried out to validate the TWINS prediction program for rolling noise, as described in part 1 of this paper. This second part presents the experimental results of vibration and noise during train pass-bys and compares them with predictions from the

  4. Development and validation of a predictive outcome score of cerebral venous thrombosis

    NARCIS (Netherlands)

    Koopman, K; Uyttenboogaart, M; Vroomen, P C; van der Meer, J; De Keyser, J; Luijckx, G J

    2009-01-01

    Background and purpose: Cerebral venous thrombosis (CVT) is a rare disease with a Variable outcome. The aim of this study was to develop and validate a predictive outcome score for CVT patients. Methods: The score was based on the 8 predictive variables of poor Outcome (modified Rankin Scale score>2

  5. Bayesian Calibration, Validation and Uncertainty Quantification for Predictive Modelling of Tumour Growth: A Tutorial.

    Science.gov (United States)

    Collis, Joe; Connor, Anthony J; Paczkowski, Marcin; Kannan, Pavitra; Pitt-Francis, Joe; Byrne, Helen M; Hubbard, Matthew E

    2017-03-13

    In this work, we present a pedagogical tumour growth example, in which we apply calibration and validation techniques to an uncertain, Gompertzian model of tumour spheroid growth. The key contribution of this article is the discussion and application of these methods (that are not commonly employed in the field of cancer modelling) in the context of a simple model, whose deterministic analogue is widely known within the community. In the course of the example, we calibrate the model against experimental data that are subject to measurement errors, and then validate the resulting uncertain model predictions. We then analyse the sensitivity of the model predictions to the underlying measurement model. Finally, we propose an elementary learning approach for tuning a threshold parameter in the validation procedure in order to maximize predictive accuracy of our validated model.

  6. A validation test for Adagio through replication of Big Hill and Bayou Choctaw JAS3D models.

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byoung Yoon

    2013-06-01

    JAS3D, a three dimensional iterative solid mechanics code, has been used for structural analyses for the Strategic Petroleum Reserve system since the 1990s. JAS3D is no longer supported by Sandia National Laboratories, and has been replaced by Adagio. To validate the transition from JAS3D to Adagio, the existing JAS3D input decks and user subroutines for Bayou Choctaw and Big Hill models were converted for use with Adagio. The calculation results from the Adagio runs are compared to the JAS3D. Since the Adagio results are very similar to the JAS3D results, Adagio is judged to be performing satisfactorily.

  7. External model validation of binary clinical risk prediction models in cardiovascular and thoracic surgery.

    Science.gov (United States)

    Hickey, Graeme L; Blackstone, Eugene H

    2016-08-01

    Clinical risk-prediction models serve an important role in healthcare. They are used for clinical decision-making and measuring the performance of healthcare providers. To establish confidence in a model, external model validation is imperative. When designing such an external model validation study, thought must be given to patient selection, risk factor and outcome definitions, missing data, and the transparent reporting of the analysis. In addition, there are a number of statistical methods available for external model validation. Execution of a rigorous external validation study rests in proper study design, application of suitable statistical methods, and transparent reporting.

  8. [Early pregnancy risk: development and validation of a predictive instrument].

    Science.gov (United States)

    Burrows, R; Rosales, M E; Díaz, M; Muzzo, S

    1994-06-01

    An early pregnancy risk scale, with scores ranging from 11 to 66 points from lower to higher risk, was constructed using variables associated with teenager's pregnancy. This scale was applied to 3000 female teenagers, coming from Metropolitan Santiago public schools. The sample was divided in three risk groups: group A (high risk) with scores equal or over 35 points, group B (low risk) with scores equal or below 20 points and group B (intermediate risk) with scores between 20.1 and 34.9 points. These girls were followed during 2 years. During this period, 84 girls became pregnant, 24 of 184 (13%) in group A, 60 of 2332 (2.6%) in group C and none of 307 in group B. There were 104 school desertions in group A and 37 in group B. To study associations and analyze risk, the sample was divided in two risk groups: high, with scores over 27 and low, with scores below 27. There was a high association between pregnancy risk score and the occurrence of pregnancy (RR 5.25 p school desertion (RR 3.32 p School desertion was predicted with a 74% sensitivity and 56% specificity. The importance variable weighing using multiple regression models, to improve the predictor's sensitivity and specificity, is discussed.

  9. Predicting interactions from mechanistic information: can omic data validate theories?

    Science.gov (United States)

    Borgert, Christopher J

    2007-09-01

    To address the most pressing and relevant issues for improving mixture risk assessment, researchers must first recognize that risk assessment is driven by both regulatory requirements and scientific research, and that regulatory concerns may expand beyond the purely scientific interests of researchers. Concepts of "mode of action" and "mechanism of action" are used in particular ways within the regulatory arena, depending on the specific assessment goals. The data requirements for delineating a mode of action and predicting interactive toxicity in mixtures are not well defined from a scientific standpoint due largely to inherent difficulties in testing certain underlying assumptions. Understanding the regulatory perspective on mechanistic concepts will be important for designing experiments that can be interpreted clearly and applied in risk assessments without undue reliance on extrapolation and assumption. In like fashion, regulators and risk assessors can be better equipped to apply mechanistic data if the concepts underlying mechanistic research and the limitations that must be placed on interpretation of mechanistic data are understood. This will be critically important for applying new technologies to risk assessment, such as functional genomics, proteomics, and metabolomics. It will be essential not only for risk assessors to become conversant with the language and concepts of mechanistic research, including new omic technologies, but also, for researchers to become more intimately familiar with the challenges and needs of risk assessment.

  10. Validation of DEM prediction for granular avalanches on irregular terrain

    Science.gov (United States)

    Mead, Stuart R.; Cleary, Paul W.

    2015-09-01

    Accurate numerical simulation can provide crucial information useful for a greater understanding of destructive granular mass movements such as rock avalanches, landslides, and pyroclastic flows. It enables more informed and relatively low cost investigation of significant risk factors, mitigation strategy effectiveness, and sensitivity to initial conditions, material, or soil properties. In this paper, a granular avalanche experiment from the literature is reanalyzed and used as a basis to assess the accuracy of discrete element method (DEM) predictions of avalanche flow. Discrete granular approaches such as DEM simulate the motion and collisions of individual particles and are useful for identifying and investigating the controlling processes within an avalanche. Using a superquadric shape representation, DEM simulations were found to accurately reproduce transient and static features of the avalanche. The effect of material properties on the shape of the avalanche deposit was investigated. The simulated avalanche deposits were found to be sensitive to particle shape and friction, with the particle shape causing the sensitivity to friction to vary. The importance of particle shape, coupled with effect on the sensitivity to friction, highlights the importance of quantifying and including particle shape effects in numerical modeling of granular avalanches.

  11. Spatial statistical modeling of shallow landslides—Validating predictions for different landslide inventories and rainfall events

    Science.gov (United States)

    von Ruette, Jonas; Papritz, Andreas; Lehmann, Peter; Rickli, Christian; Or, Dani

    2011-10-01

    Statistical models that exploit the correlation between landslide occurrence and geomorphic properties are often used to map the spatial occurrence of shallow landslides triggered by heavy rainfalls. In many landslide susceptibility studies, the true predictive power of the statistical model remains unknown because the predictions are not validated with independent data from other events or areas. This study validates statistical susceptibility predictions with independent test data. The spatial incidence of landslides, triggered by an extreme rainfall in a study area, was modeled by logistic regression. The fitted model was then used to generate susceptibility maps for another three study areas, for which event-based landslide inventories were also available. All the study areas lie in the northern foothills of the Swiss Alps. The landslides had been triggered by heavy rainfall either in 2002 or 2005. The validation was designed such that the first validation study area shared the geomorphology and the second the triggering rainfall event with the calibration study area. For the third validation study area, both geomorphology and rainfall were different. All explanatory variables were extracted for the logistic regression analysis from high-resolution digital elevation and surface models (2.5 m grid). The model fitted to the calibration data comprised four explanatory variables: (i) slope angle (effect of gravitational driving forces), (ii) vegetation type (grassland and forest; root reinforcement), (iii) planform curvature (convergent water flow paths), and (iv) contributing area (potential supply of water). The area under the Receiver Operating Characteristic (ROC) curve ( AUC) was used to quantify the predictive performance of the logistic regression model. The AUC values were computed for the susceptibility maps of the three validation study areas (validation AUC), the fitted susceptibility map of the calibration study area (apparent AUC: 0.80) and another

  12. Predictive validity of the Slovene Matura exam for academic achievement in humanities and social sciences

    Directory of Open Access Journals (Sweden)

    Gregor Sočan

    2016-09-01

    Full Text Available Matura is a Slovene national examination, which all the students take after successfully completing secondary education. The Matura has two major functions; it is a high school final examination and a selection instrument for University. The goal of the study was to investigate the predictive validity of Matura for predicting academic success in study programmes in the area of humanities and social sciences. Predictive validity was studied both from the traditional correlational perspective and from the multilevel regression perspective. Additionally, we checked for possible differences in predictive validity between study programmes. According to the expectations, the Matura score was a relatively strong and robust predictor of later academic achievement, even after controlling for the high school overall grade. The results support the use of Matura scores in selection of candidates for undergraduate studies in humanities and social sciences.

  13. Replication of LDL GWAs hits in PROSPER/PHASE as validation for future (pharmaco)genetic analyses

    LENUS (Irish Health Repository)

    Trompet, Stella

    2011-10-06

    Abstract Background The PHArmacogenetic study of Statins in the Elderly at risk (PHASE) is a genome wide association study in the PROspective Study of Pravastatin in the Elderly at risk for vascular disease (PROSPER) that investigates the genetic variation responsible for the individual variation in drug response to pravastatin. Statins lower LDL-cholesterol in general by 30%, however not in all subjects. Moreover, clinical response is highly variable and adverse effects occur in a minority of patients. In this report we first describe the rationale of the PROSPER\\/PHASE project and second show that the PROSPER\\/PHASE study can be used to study pharmacogenetics in the elderly. Methods The genome wide association study (GWAS) was conducted using the Illumina 660K-Quad beadchips following manufacturer\\'s instructions. After a stringent quality control 557,192 SNPs in 5,244 subjects were available for analysis. To maximize the availability of genetic data and coverage of the genome, imputation up to 2.5 million autosomal CEPH HapMap SNPs was performed with MACH imputation software. The GWAS for LDL-cholesterol is assessed with an additive linear regression model in PROBABEL software, adjusted for age, sex, and country of origin to account for population stratification. Results Forty-two SNPs reached the GWAS significant threshold of p = 5.0e-08 in 5 genomic loci (APOE\\/APOC1; LDLR; FADS2\\/FEN1; HMGCR; PSRC1\\/CELSR5). The top SNP (rs445925, chromosome 19) with a p-value of p = 2.8e-30 is located within the APOC1 gene and near the APOE gene. The second top SNP (rs6511720, chromosome 19) with a p-value of p = 5.22e-15 is located within the LDLR gene. All 5 genomic loci were previously associated with LDL-cholesterol levels, no novel loci were identified. Replication in WOSCOPS and CARE confirmed our results. Conclusion With the GWAS in the PROSPER\\/PHASE study we confirm the previously found genetic associations with LDL-cholesterol levels. With this proof

  14. Incremental validity of positive and negative valence in predicting personality disorder.

    Science.gov (United States)

    Simms, Leonard J; Yufik, Tom; Gros, Daniel F

    2010-04-01

    The Big Seven model of personality includes five dimensions similar to the Big Five model as well as two evaluative dimensions—Positive Valence (PV) and Negative Valence (NV)—which reflect extremely positive and negative person descriptors, respectively. Recent theory and research have suggested that PV and NV predict significant variance in personality disorder (PD) above that predicted by the Big Five, but firm conclusions have not been possible because previous studies have been limited to only single measures of PV, NV, and the Big Five traits. In the present study, we replicated and extended previous findings using three markers of all key constructs—including PV, NV, and the Big Five—in a diverse sample of 338 undergraduates. Results of hierarchical multiple regression analyses revealed that PV incrementally predicted Narcissistic and Histrionic PDs above the Big Five and that NV nonspecifically incremented the prediction of most PDs. Implications for dimensional models of personality pathology are discussed.

  15. Predicting folivorous primate abundance: validation of a nutritional model.

    Science.gov (United States)

    Chapman, Colin A; Chapman, Lauren J; Naughton-Treves, Lisa; Lawes, Michael J; McDowell, Lee R

    2004-02-01

    Understanding the determinants of animal abundance has become more vital as ecologists are increasingly asked to apply their knowledge to the construction of informed management plans. However, there are few general models are available to explain variation in abundance. Some notable exceptions are studies of folivorous primates, in which the protein-to-fiber ratio of foods has been shown to predict biomass. Here we examine the generality of Milton's [American Naturalist 114:363-378, 1979] protein/fiber model by providing a detailed analysis of diet selection in black-and-white colobus monkeys (Colobus guereza), and applying the model to populations shown to be stable; an assumption not previously examined. Based on observations of two groups of black-and-white colobus in Kibale National Park, Uganda, and one group in a forest fragment, we documented that the animals selected young leaves that had more protein, were more digestible, and had a higher protein-to-fiber ratio than mature leaves. The mature leaves did not differ from young leaves with respect to secondary compounds or mineral content (with the exceptions of copper and zinc). All of the colobus groups selected foods with a high protein-to-fiber ratios. However, one group also selected more digestible foods, and in another group, foraging efforts were positively related to zinc and negatively related to potassium. Previous studies that examined Milton's protein/fiber model did not demonstrate that the study populations were stable. If some populations were not at carrying capacity, then the correlations drawn between food availability and/or quality and folivore biomass may have been spurious. To address this issue, we censused a series of forest fragments in 1995 and again in 2000. We found that the populations in these fragments had declined from 165 in 1995 to 119 animals in 2000. However, based on evidence of population stability and lack of forest disturbance, we concluded that five of the original

  16. Observations on CFD Verification and Validation from the AIAA Drag Prediction Workshops

    Science.gov (United States)

    Morrison, Joseph H.; Kleb, Bil; Vassberg, John C.

    2014-01-01

    The authors provide observations from the AIAA Drag Prediction Workshops that have spanned over a decade and from a recent validation experiment at NASA Langley. These workshops provide an assessment of the predictive capability of forces and moments, focused on drag, for transonic transports. It is very difficult to manage the consistency of results in a workshop setting to perform verification and validation at the scientific level, but it may be sufficient to assess it at the level of practice. Observations thus far: 1) due to simplifications in the workshop test cases, wind tunnel data are not necessarily the “correct” results that CFD should match, 2) an average of core CFD data are not necessarily a better estimate of the true solution as it is merely an average of other solutions and has many coupled sources of variation, 3) outlier solutions should be investigated and understood, and 4) the DPW series does not have the systematic build up and definition on both the computational and experimental side that is required for detailed verification and validation. Several observations regarding the importance of the grid, effects of physical modeling, benefits of open forums, and guidance for validation experiments are discussed. The increased variation in results when predicting regions of flow separation and increased variation due to interaction effects, e.g., fuselage and horizontal tail, point out the need for validation data sets for these important flow phenomena. Experiences with a recent validation experiment at NASA Langley are included to provide guidance on validation experiments.

  17. Statistical external validation and consensus modeling: a QSPR case study for Koc prediction.

    Science.gov (United States)

    Gramatica, Paola; Giani, Elisa; Papa, Ester

    2007-03-01

    The soil sorption partition coefficient (log K(oc)) of a heterogeneous set of 643 organic non-ionic compounds, with a range of more than 6 log units, is predicted by a statistically validated QSAR modeling approach. The applied multiple linear regression (ordinary least squares, OLS) is based on a variety of theoretical molecular descriptors selected by the genetic algorithms-variable subset selection (GA-VSS) procedure. The models were validated for predictivity by different internal and external validation approaches. For external validation we applied self organizing maps (SOM) to split the original data set: the best four-dimensional model, developed on a reduced training set of 93 chemicals, has a predictivity of 78% when applied on 550 validation chemicals (prediction set). The selected molecular descriptors, which could be interpreted through their mechanistic meaning, were compared with the more common physico-chemical descriptors log K(ow) and log S(w). The chemical applicability domain of each model was verified by the leverage approach in order to propose only reliable data. The best predicted data were obtained by consensus modeling from 10 different models in the genetic algorithm model population.

  18. Experimental validation of finite element and boundary element methods for predicting structural vibration and radiated noise

    Science.gov (United States)

    Seybert, A. F.; Wu, T. W.; Wu, X. F.

    1994-01-01

    This research report is presented in three parts. In the first part, acoustical analyses were performed on modes of vibration of the housing of a transmission of a gear test rig developed by NASA. The modes of vibration of the transmission housing were measured using experimental modal analysis. The boundary element method (BEM) was used to calculate the sound pressure and sound intensity on the surface of the housing and the radiation efficiency of each mode. The radiation efficiency of each of the transmission housing modes was then compared to theoretical results for a finite baffled plate. In the second part, analytical and experimental validation of methods to predict structural vibration and radiated noise are presented. A rectangular box excited by a mechanical shaker was used as a vibrating structure. Combined finite element method (FEM) and boundary element method (BEM) models of the apparatus were used to predict the noise level radiated from the box. The FEM was used to predict the vibration, while the BEM was used to predict the sound intensity and total radiated sound power using surface vibration as the input data. Vibration predicted by the FEM model was validated by experimental modal analysis; noise predicted by the BEM was validated by measurements of sound intensity. Three types of results are presented for the total radiated sound power: sound power predicted by the BEM model using vibration data measured on the surface of the box; sound power predicted by the FEM/BEM model; and sound power measured by an acoustic intensity scan. In the third part, the structure used in part two was modified. A rib was attached to the top plate of the structure. The FEM and BEM were then used to predict structural vibration and radiated noise respectively. The predicted vibration and radiated noise were then validated through experimentation.

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

    Science.gov (United States)

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

    2011-01-01

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

  20. Self-control predicts exercise behavior by force of habit, a conceptual replication of Adriaanse et al.

    NARCIS (Netherlands)

    Gillebaart, Marleen; Adriaanse, Marieke A.

    2017-01-01

    A recent study suggests that habits play a mediating role in the association between trait self-control and eating behavior, supporting a notion of effortless processes in trait self-control (Adriaanse et al., 2014). We conceptually replicated this research in the area of exercise behavior,

  1. Assessing Predictive Validity of Pressure Ulcer Risk Scales- A Systematic Review and Meta-Analysis

    OpenAIRE

    2016-01-01

    Background: The purpose of this study was to present a scientific reason for pressure ulcer risk scales: Cubbin& Jackson modified Braden, Norton, and Waterlow, as a nursing diagnosis tool by utilizing predictive validity of pressure sores. Methods: Articles published between 1966 and 2013 from periodicals indexed in the Ovid Medline, Embase, CINAHL, KoreaMed, NDSL, and other databases were selected using the key word “pressure ulcer”. QUADAS-II was applied for assessment for internal validity...

  2. Prospective validation of two models predicting pregnancy leading to live birth among untreated subfertile couples.

    Science.gov (United States)

    Hunault, Claudine C; Laven, Joop S E; van Rooij, Ilse A J; Eijkemans, Marinus J C; te Velde, Egbert R; Habbema, J Dik F

    2005-06-01

    Models predicting clinical outcome need external validation before they can be applied safely in daily practice. This study aimed to validate two models for the prediction of the chance of treatment-independent pregnancy leading to live birth among subfertile couples. The first model uses the woman's age, duration and type of subfertility, percentage of progressive sperm motility and referral status. The second model in addition uses the result of the post-coital test (PCT). For validation, these characteristics were collected prospectively in two University hospitals for 302 couples consulting for subfertility. The models' ability to distinguish between women who became pregnant and women who did not (discrimination) and the agreement between predicted and observed probabilities of treatment-independent pregnancy (calibration) were assessed. The discrimination of both models was slightly lower in the validation sample than in the original sample which provided the model. Calibration was good: the observed and predicted probabilities of treatment-independent pregnancy leading to live birth did not differ for both models. The chance of pregnancy leading to live birth was reliably estimated in the validation sample by both models. The use of PCT improved the discrimination of the models. These models can be useful in counselling subfertile couples.

  3. The Predictive Validity of Four Intelligence Tests for School Grades: A Small Sample Longitudinal Study.

    Science.gov (United States)

    Gygi, Jasmin T; Hagmann-von Arx, Priska; Schweizer, Florine; Grob, Alexander

    2017-01-01

    Intelligence is considered the strongest single predictor of scholastic achievement. However, little is known regarding the predictive validity of well-established intelligence tests for school grades. We analyzed the predictive validity of four widely used intelligence tests in German-speaking countries: The Intelligence and Development Scales (IDS), the Reynolds Intellectual Assessment Scales (RIAS), the Snijders-Oomen Nonverbal Intelligence Test (SON-R 6-40), and the Wechsler Intelligence Scale for Children (WISC-IV), which were individually administered to 103 children (Mage = 9.17 years) enrolled in regular school. School grades were collected longitudinally after 3 years (averaged school grades, mathematics, and language) and were available for 54 children (Mage = 11.77 years). All four tests significantly predicted averaged school grades. Furthermore, the IDS and the RIAS predicted both mathematics and language, while the SON-R 6-40 predicted mathematics. The WISC-IV showed no significant association with longitudinal scholastic achievement when mathematics and language were analyzed separately. The results revealed the predictive validity of currently used intelligence tests for longitudinal scholastic achievement in German-speaking countries and support their use in psychological practice, in particular for predicting averaged school grades. However, this conclusion has to be considered as preliminary due to the small sample of children observed.

  4. The Predictive Validity of Four Intelligence Tests for School Grades: A Small Sample Longitudinal Study

    Science.gov (United States)

    Gygi, Jasmin T.; Hagmann-von Arx, Priska; Schweizer, Florine; Grob, Alexander

    2017-01-01

    Intelligence is considered the strongest single predictor of scholastic achievement. However, little is known regarding the predictive validity of well-established intelligence tests for school grades. We analyzed the predictive validity of four widely used intelligence tests in German-speaking countries: The Intelligence and Development Scales (IDS), the Reynolds Intellectual Assessment Scales (RIAS), the Snijders-Oomen Nonverbal Intelligence Test (SON-R 6-40), and the Wechsler Intelligence Scale for Children (WISC-IV), which were individually administered to 103 children (Mage = 9.17 years) enrolled in regular school. School grades were collected longitudinally after 3 years (averaged school grades, mathematics, and language) and were available for 54 children (Mage = 11.77 years). All four tests significantly predicted averaged school grades. Furthermore, the IDS and the RIAS predicted both mathematics and language, while the SON-R 6-40 predicted mathematics. The WISC-IV showed no significant association with longitudinal scholastic achievement when mathematics and language were analyzed separately. The results revealed the predictive validity of currently used intelligence tests for longitudinal scholastic achievement in German-speaking countries and support their use in psychological practice, in particular for predicting averaged school grades. However, this conclusion has to be considered as preliminary due to the small sample of children observed. PMID:28348543

  5. Predicting the chance of vaginal delivery after one cesarean section: validation and elaboration of a published prediction model.

    Science.gov (United States)

    Fagerberg, Marie C; Maršál, Karel; Källén, Karin

    2015-05-01

    We aimed to validate a widely used US prediction model for vaginal birth after cesarean (Grobman et al. [8]) and modify it to suit Swedish conditions. Women having experienced one cesarean section and at least one subsequent delivery (n=49,472) in the Swedish Medical Birth Registry 1992-2011 were randomly divided into two data sets. In the development data set, variables associated with successful trial of labor were identified using multiple logistic regression. The predictive ability of the estimates previously published by Grobman et al., and of our modified and new estimates, respectively, was then evaluated using the validation data set. The accuracy of the models for prediction of vaginal birth after cesarean was measured by area under the receiver operating characteristics curve. For maternal age, body mass index, prior vaginal delivery, and prior labor arrest, the odds ratio estimates for vaginal birth after cesarean were similar to those previously published. The prediction accuracy increased when information on indication for the previous cesarean section was added (from area under the receiver operating characteristics curve=0.69-0.71), and increased further when maternal height and delivery unit cesarean section rates were included (area under the receiver operating characteristics curve=0.74). The correlation between the individual predicted vaginal birth after cesarean probability and the observed trial of labor success rate was high in all the respective predicted probability decentiles. Customization of prediction models for vaginal birth after cesarean is of considerable value. Choosing relevant indicators for a Swedish setting made it possible to achieve excellent prediction accuracy for success in trial of labor after cesarean. During the delicate process of counseling about preferred delivery mode after one cesarean section, considering the results of our study may facilitate the choice between a trial of labor or an elective repeat cesarean

  6. External validation and prediction employing the predictive squared correlation coefficient test set activity mean vs training set activity mean.

    Science.gov (United States)

    Schüürmann, Gerrit; Ebert, Ralf-Uwe; Chen, Jingwen; Wang, Bin; Kühne, Ralph

    2008-11-01

    The external prediction capability of quantitative structure-activity relationship (QSAR) models is often quantified using the predictive squared correlation coefficient, q (2). This index relates the predictive residual sum of squares, PRESS, to the activity sum of squares, SS, without postprocessing of the model output, the latter of which is automatically done when calculating the conventional squared correlation coefficient, r (2). According to the current OECD guidelines, q (2) for external validation should be calculated with SS referring to the training set activity mean. Our present findings including a mathematical proof demonstrate that this approach yields a systematic overestimation of the prediction capability that is triggered by the difference between the training and test set activity means. Example calculations with three regression models and data sets taken from literature show further that for external test sets, q (2) based on the training set activity mean may become even larger than r (2). As a consequence, we suggest to always use the test set activity mean when quantifying the external prediction capability through q (2) and to revise the respective OECD guidance document accordingly. The discussion includes a comparison between r (2) and q (2) value ranges and the q (2) statistics for cross-validation.

  7. Systematic mutagenesis of genes encoding predicted autotransported proteins of Burkholderia pseudomallei identifies factors mediating virulence in mice, net intracellular replication and a novel protein conferring serum resistance.

    Directory of Open Access Journals (Sweden)

    Natalie R Lazar Adler

    Full Text Available Burkholderia pseudomallei is the causative agent of the severe tropical disease melioidosis, which commonly presents as sepsis. The B. pseudomallei K96243 genome encodes eleven predicted autotransporters, a diverse family of secreted and outer membrane proteins often associated with virulence. In a systematic study of these autotransporters, we constructed insertion mutants in each gene predicted to encode an autotransporter and assessed them for three pathogenesis-associated phenotypes: virulence in the BALB/c intra-peritoneal mouse melioidosis model, net intracellular replication in J774.2 murine macrophage-like cells and survival in 45% (v/v normal human serum. From the complete repertoire of eleven autotransporter mutants, we identified eight mutants which exhibited an increase in median lethal dose of 1 to 2-log10 compared to the isogenic parent strain (bcaA, boaA, boaB, bpaA, bpaC, bpaE, bpaF and bimA. Four mutants, all demonstrating attenuation for virulence, exhibited reduced net intracellular replication in J774.2 macrophage-like cells (bimA, boaB, bpaC and bpaE. A single mutant (bpaC was identified that exhibited significantly reduced serum survival compared to wild-type. The bpaC mutant, which demonstrated attenuation for virulence and net intracellular replication, was sensitive to complement-mediated killing via the classical and/or lectin pathway. Serum resistance was rescued by in trans complementation. Subsequently, we expressed recombinant proteins of the passenger domain of four predicted autotransporters representing each of the phenotypic groups identified: those attenuated for virulence (BcaA, those attenuated for virulence and net intracellular replication (BpaE, the BpaC mutant with defects in virulence, net intracellular replication and serum resistance and those displaying wild-type phenotypes (BatA. Only BcaA and BpaE elicited a strong IFN-γ response in a restimulation assay using whole blood from seropositive donors

  8. Systematic mutagenesis of genes encoding predicted autotransported proteins of Burkholderia pseudomallei identifies factors mediating virulence in mice, net intracellular replication and a novel protein conferring serum resistance.

    Science.gov (United States)

    Lazar Adler, Natalie R; Stevens, Mark P; Dean, Rachel E; Saint, Richard J; Pankhania, Depesh; Prior, Joann L; Atkins, Timothy P; Kessler, Bianca; Nithichanon, Arnone; Lertmemongkolchai, Ganjana; Galyov, Edouard E

    2015-01-01

    Burkholderia pseudomallei is the causative agent of the severe tropical disease melioidosis, which commonly presents as sepsis. The B. pseudomallei K96243 genome encodes eleven predicted autotransporters, a diverse family of secreted and outer membrane proteins often associated with virulence. In a systematic study of these autotransporters, we constructed insertion mutants in each gene predicted to encode an autotransporter and assessed them for three pathogenesis-associated phenotypes: virulence in the BALB/c intra-peritoneal mouse melioidosis model, net intracellular replication in J774.2 murine macrophage-like cells and survival in 45% (v/v) normal human serum. From the complete repertoire of eleven autotransporter mutants, we identified eight mutants which exhibited an increase in median lethal dose of 1 to 2-log10 compared to the isogenic parent strain (bcaA, boaA, boaB, bpaA, bpaC, bpaE, bpaF and bimA). Four mutants, all demonstrating attenuation for virulence, exhibited reduced net intracellular replication in J774.2 macrophage-like cells (bimA, boaB, bpaC and bpaE). A single mutant (bpaC) was identified that exhibited significantly reduced serum survival compared to wild-type. The bpaC mutant, which demonstrated attenuation for virulence and net intracellular replication, was sensitive to complement-mediated killing via the classical and/or lectin pathway. Serum resistance was rescued by in trans complementation. Subsequently, we expressed recombinant proteins of the passenger domain of four predicted autotransporters representing each of the phenotypic groups identified: those attenuated for virulence (BcaA), those attenuated for virulence and net intracellular replication (BpaE), the BpaC mutant with defects in virulence, net intracellular replication and serum resistance and those displaying wild-type phenotypes (BatA). Only BcaA and BpaE elicited a strong IFN-γ response in a restimulation assay using whole blood from seropositive donors and were

  9. Multiple mini-interview predictive validity for performance on a pharmacy licensing examination.

    Science.gov (United States)

    Cameron, Andrea J; MacKeigan, Linda D; Mitsakakis, Nicholas; Pugsley, John A

    2017-04-01

    Predictive validity studies on the use of the multiple mini-interview (MMI) have been primarily in medicine. This study sought to determine the predictive validity of the MMI for performance within a pharmacy programme and on the Pharmacy Examining Board of Canada (PEBC) Qualifying Examination for licensure, and to compare the predictive validity of the MMI with that of pre-pharmacy grade point average (GPA) and Pharmacy College Admission Test (PCAT) score. Admissions data for 223 graduates of the pharmacy programme at the University of Toronto were matched to programme and licensure outcome measures. Multiple linear regression assessed the predictive ability of the MMI, pre-pharmacy GPA, PCAT and covariates for performance in final-year experiential rotations, cumulative GPA (cGPA) and PEBC-MCQ (multiple-choice question examination) and PEBC-OSCE (objective structured clinical examination) overall and subcomponent scores. The PCAT, pre-pharmacy GPA and age significantly predicted the PEBC-MCQ overall score. The MMI was the only significant predictor of overall score on the PEBC-OSCE (β = 0.17, p = 0.02); it also predicted communication and performance subscores. Scores on the PCAT and female gender predicted the communication subscore. Pre-pharmacy GPA, age and female gender significantly predicted cGPA. The MMI was the only significant predictor of institutional/ambulatory rotation score (β = 0.26, p = 0.00). The MMI, designed to measure non-academic attributes including communication, motivation and problem-solving skills, was the only admissions tool with significant predictive validity for performance on the PEBC-OSCE national pharmacy certification examination and in an institutional/ambulatory rotation. These findings, from a single cohort of undergraduates, provide the first report of the predictive validity of the MMI for performance on pharmacy licensure examinations and thereby strengthen the evidence for its use in health professions selection. Prior

  10. Enterococcal bloodstream infection. Design and validation of a mortality prediction rule

    OpenAIRE

    Perez-Garcia, Alejandra; Landecho, Manuel; Beunza Nuin, Juan Jose; Conde-Estévez, D; Horcajada, J.P.; Grau, S.; Gea Sánchez, Alfredo; E. Mauleón; Sorli, L.; Gómez, J.; Terradas, R.; Lucena, J.F. (Juan F.); Alegre Garrido, Félix; A. Huerta; Pozo, José Luis del

    2016-01-01

    To develop a prediction rule to describe the risk of death as a result of enterococcal bloodstream infection. A prediction rule was developed by analysing data collected from 122 patients diagnosed with enterococcal BSI admitted to the Clínica Universidad de Navarra (Pamplona, Spain); and validated by confirming its accuracy with the data of an external population (Hospital del Mar, Barcelona). According to this model, independent significant predictors for the risk of death were being diabet...

  11. A Multi-Center Prospective Derivation and Validation of a Clinical Prediction Tool for Severe Clostridium difficile Infection.

    LENUS (Irish Health Repository)

    Na, Xi

    2015-04-23

    Prediction of severe clinical outcomes in Clostridium difficile infection (CDI) is important to inform management decisions for optimum patient care. Currently, treatment recommendations for CDI vary based on disease severity but validated methods to predict severe disease are lacking. The aim of the study was to derive and validate a clinical prediction tool for severe outcomes in CDI.

  12. Error criteria for cross validation in the context of chaotic time series prediction.

    Science.gov (United States)

    Lim, Teck Por; Puthusserypady, Sadasivan

    2006-03-01

    The prediction of a chaotic time series over a long horizon is commonly done by iterating one-step-ahead prediction. Prediction can be implemented using machine learning methods, such as radial basis function networks. Typically, cross validation is used to select prediction models based on mean squared error. The bias-variance dilemma dictates that there is an inevitable tradeoff between bias and variance. However, invariants of chaotic systems are unchanged by linear transformations; thus, the bias component may be irrelevant to model selection in the context of chaotic time series prediction. Hence, the use of error variance for model selection, instead of mean squared error, is examined. Clipping is introduced, as a simple way to stabilize iterated predictions. It is shown that using the error variance for model selection, in combination with clipping, may result in better models.

  13. Predictive Validity of the Columbia-Suicide Severity Rating Scale for Short-Term Suicidal Behavior

    DEFF Research Database (Denmark)

    Conway, Paul Maurice; Erlangsen, Annette; Teasdale, Thomas William

    2016-01-01

    Objectives: Using the Columbia-Suicide Severity Rating Scale (C-SSRS), we examined the predictive and incremental predictive validity of past-month suicidal behavior and ideation for short-term suicidal behavior among adolescents at a high risk of suicide. Methods: The study was conducted in 2014...... behavior predicted subsequent suicidal behavior (actual attempts and suicidal behavior of any type, including preparatory acts, aborted, interrupted and actual attempts; mean follow-up of 80.8 days, SD = 52.4). Furthermore, we examined whether suicidal ideation severity and intensity incrementally...... predicted suicidal behavior at follow-up over and above suicidal behavior at baseline. Results: Actual suicide attempts at baseline strongly predicted suicide attempts at follow-up. Baseline suicidal ideation severity and intensity did not significantly predict future actual attempts over and above baseline...

  14. Predictive Validity of the WISC-R for White and Mexican-American Children.

    Science.gov (United States)

    Reynolds, Cecil R.; Gutkin, Terry B.

    Predictive validity of the Weschler Intelligence Scale for Children-Revised (WISC-R), was investigated with 174 Chicanos and 94 Anglos, ages 10-11, who were referred for psychological services. Wide Range Achievement Test Reading, Spelling, and Arithmetic subtest scores were each regressed on WISC-R Verbal, Performance and Full Scale Intelligence…

  15. Predictive validity of proposed remission criteria in first-episode schizophrenic patients responding to antipsychotics

    NARCIS (Netherlands)

    Wunderink, Lex; Nienhuis, Fokko J.; Sytema, Sjoerd; Wiersma, Durk

    2007-01-01

    The objective of this study was to examine the predictive validity of the remission criteria proposed by Andreasen et all in first-episode patients responding to antipsychotics. Antipsychotic responsive patients with first-episode schizophrenia showing symptom remission (n = 60) were compared with p

  16. Predictive Validity of UAS/RPA Sensor Operator Training Qualification Measures

    Science.gov (United States)

    2015-01-30

    examined the predictive validity of the AFOQT Pilot composite, Revised NEO Personality Inventory (NEO-PI-R; Costa & McCrae , 1992), and a...2nd ed.). Mahwah, NJ: Erlbaum. Costa , P. T., Jr., & McCrae , R. R. (1992). NEO PI-R professional manual. Odessa, FL: Psychological Assessment

  17. Concurrent and Predictive Validity of the Phelps Kindergarten Readiness Scale-II

    Science.gov (United States)

    Duncan, Jennifer; Rafter, Erin M.

    2005-01-01

    The purpose of this research was to establish the concurrent and predictive validity of the Phelps Kindergarten Readiness Scale, Second Edition (PKRS-II; L. Phelps, 2003). Seventy-four kindergarten students of diverse ethnic backgrounds enrolled in a northeastern suburban school participated in the study. The concurrent administration of the…

  18. Progression to microalbuminuria in type 1 diabetes: development and validation of a prediction rule

    NARCIS (Netherlands)

    Vergouwe, Y.; Soedamah-Muthu, S.S.; Zgibor, J.; Chaturvedi, N.; Forsblom, C.; Snell-Bergeon, J.K.; Maahs, D.M.; Groop, P.H.; Rewers, M.; Orchard, T.J.; Fuller, J.H.; Moons, K.G.M.

    2010-01-01

    AIMS/HYPOTHESIS: Microalbuminuria is common in type 1 diabetes and is associated with an increased risk of renal and cardiovascular disease. We aimed to develop and validate a clinical prediction rule that estimates the absolute risk of microalbuminuria. METHODS: Data from the European Diabetes Pros

  19. Predictive Validity of Three Preschool Developmental Assessment Instruments for the Academic Performance of Kindergarten Students.

    Science.gov (United States)

    Wenner, George

    The predictive validity of an original Piagetian instrument (the Piagetian Task Instrument) was compared with that of two frequently used published screening tests for children entering kindergarten: (1) the Brigance K-1 Screen, and (2) the Merrill Language Screening Test. The relative contribution of each test was determined when they were…

  20. Searching for Predictive and Developmental Validity in a Motivational Reasoning Hierarchy.

    Science.gov (United States)

    Herman, William E.

    Nearly a quarter of a century ago, John G. Nicholls proposed the four developmental levels of motivational reasoning that focused upon the roles that ability and effort play in academic success. These levels theoretically begin at early childhood and end at adolescence. This report attempts to validate the developmental and predictive nature of…

  1. Predictive Validity of the MMPI-2 Clinical, PSY-5, and RC Scales for Therapy Disruptive Behavior

    NARCIS (Netherlands)

    Scholte, W.; Tiemens, B.G.; Verheul, R.; Meerman, A.; Egger, J.; Hutschemaekers, G.

    2012-01-01

    Background. Impulsive acts, parasuicidal behavior, and other therapy disruptive incidents occur frequently in the treatment of patients with personality disorders and increase the risk that patients will drop out of treatment. Objective. This study examined the predictive validity of the Minnesota M

  2. Predictive Validity of the MCAT for Students with Two Sets of Scores.

    Science.gov (United States)

    Hojat, Mohammadreza; And Others

    1985-01-01

    The question of which set of scores for those students who retake the Medical College Admission Test yields a better predictive validity is addressed. Five sets were considered as predictors. Twenty-five criteria were used, including grades earned in the freshman and sophomore years. (Author/MLW)

  3. The Predictive Validity of using Admissions Testing and Multiple Mini-interviews in Undergraduate University Admissions

    DEFF Research Database (Denmark)

    Makransky, Guido; Havmose, Philip; Vang, Maria Louison;

    2016-01-01

    The aim of this study was to evaluate the predictive validity of a two-step admissions procedure that included a cognitive ability test followed by multiple mini-interviews (MMI) used to assess non-cognitive skills compared to a grade-based admissions relative to subsequent drop-out rates and aca...

  4. Project Evaluation: Validation of a Scale and Analysis of Its Predictive Capacity

    Science.gov (United States)

    Fernandes Malaquias, Rodrigo; de Oliveira Malaquias, Fernanda Francielle

    2014-01-01

    The objective of this study was to validate a scale for assessment of academic projects. As a complement, we examined its predictive ability by comparing the scores of advised/corrected projects based on the model and the final scores awarded to the work by an examining panel (approximately 10 months after the project design). Results of…

  5. The Predictive Validity of Using Admissions Testing and Multiple Mini-Interviews in Undergraduate University Admissions

    Science.gov (United States)

    Makransky, Guido; Havmose, Philip; Vang, Maria Louison; Andersen, Tonny Elmose; Nielsen, Tine

    2017-01-01

    The aim of this study was to evaluate the predictive validity of a two-step admissions procedure that included a cognitive ability test followed by multiple mini-interviews (MMIs) used to assess non-cognitive skills, compared to grade-based admissions relative to subsequent drop-out rates and academic achievement after one and two years of study.…

  6. Predictive Validity and Accuracy of Oral Reading Fluency for English Learners

    Science.gov (United States)

    Vanderwood, Michael L.; Tung, Catherine Y.; Checca, C. Jason

    2014-01-01

    The predictive validity and accuracy of an oral reading fluency (ORF) measure for a statewide assessment in English language arts was examined for second-grade native English speakers (NESs) and English learners (ELs) with varying levels of English proficiency. In addition to comparing ELs with native English speakers, the impact of English…

  7. Predictive Validity and Accuracy of Oral Reading Fluency for English Learners

    Science.gov (United States)

    Vanderwood, Michael L.; Tung, Catherine Y.; Checca, C. Jason

    2014-01-01

    The predictive validity and accuracy of an oral reading fluency (ORF) measure for a statewide assessment in English language arts was examined for second-grade native English speakers (NESs) and English learners (ELs) with varying levels of English proficiency. In addition to comparing ELs with native English speakers, the impact of English…

  8. Construct validity of the moisture subscale of the Braden Scale for Predicting Pressure Sore Risk.

    Science.gov (United States)

    Omolayo, Tolulope; Brown, Kilty; Rapp, Mary Pat; Li, Jing; Barrett, Ryan; Horn, Susan; Bergstrom, Nancy

    2013-03-01

    In this study, the construct validity of the moisture subscale of the Braden Scale for Predicting Pressure Sore Risk is partially supported by the significant inverse relationships between moisture subscale scores, the number of wet observations and soiled observations, brief changes, and differences among the moisture subscale score groups.

  9. Predictive Validity of Early Literacy Measures for Korean English Language Learners in the United States

    Science.gov (United States)

    Han, Jeanie Nam; Vanderwood, Michael L.; Lee, Catherine Y.

    2015-01-01

    This study examined the predictive validity of early literacy measures with first-grade Korean English language learners (ELLs) in the United States at varying levels of English proficiency. Participants were screened using Dynamic Indicators of Basic Early Literacy Skills (DIBELS) Phoneme Segmentation Fluency (PSF), DIBELS Nonsense Word Fluency…

  10. Validation of a New Skinfold Prediction Equation Based on Dual-Energy X-Ray Absorptiometry

    Science.gov (United States)

    Ball, Stephen; Cowan, Celsi; Thyfault, John; LaFontaine, Tom

    2014-01-01

    Skinfold prediction equations recommended by the American College of Sports Medicine underestimate body fat percentage. The purpose of this research was to validate an alternative equation for men created from dual energy x-ray absorptiometry. Two hundred ninety-seven males, aged 18-65, completed a skinfold assessment and dual energy x-ray…

  11. Predictive validity of the MMPI-2 among female offenders in a residential treatment program.

    Science.gov (United States)

    McAnulty, Richard D; McAnulty, David P; Sipp, Jennifer E; Demakis, George J; Heggestad, Eric D

    2014-01-01

    This study investigated the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) validity, clinical, restructured clinical, supplementary, and content scales in a female correctional population. The study used archival data for a final sample of 116 women who had been evaluated for acceptance into a residential rehabilitative treatment program for nonviolent female offenders in North Carolina. MMPI-2 scale elevations are reported and assessed for predictive validity in relation to treatment success, as measured by treatment attendance and graduation status. In relation to predictive validity, logistic regression analyses revealed that elevations on Scales FRS (Fears) and R (Repression) differentiated women who attended the program from women who did not. Elevations on Scales 4, DEP (Depression), Re (Responsibility), and AAS (Addiction Admission Scale) differentiated women who graduated the program from women who did not. Implications for the rehabilitation of female offenders, as well as limitations of this exploratory study, are discussed.

  12. An approach to model validation and model-based prediction -- polyurethane foam case study.

    Energy Technology Data Exchange (ETDEWEB)

    Dowding, Kevin J.; Rutherford, Brian Milne

    2003-07-01

    Enhanced software methodology and improved computing hardware have advanced the state of simulation technology to a point where large physics-based codes can be a major contributor in many systems analyses. This shift toward the use of computational methods has brought with it new research challenges in a number of areas including characterization of uncertainty, model validation, and the analysis of computer output. It is these challenges that have motivated the work described in this report. Approaches to and methods for model validation and (model-based) prediction have been developed recently in the engineering, mathematics and statistical literatures. In this report we have provided a fairly detailed account of one approach to model validation and prediction applied to an analysis investigating thermal decomposition of polyurethane foam. A model simulates the evolution of the foam in a high temperature environment as it transforms from a solid to a gas phase. The available modeling and experimental results serve as data for a case study focusing our model validation and prediction developmental efforts on this specific thermal application. We discuss several elements of the ''philosophy'' behind the validation and prediction approach: (1) We view the validation process as an activity applying to the use of a specific computational model for a specific application. We do acknowledge, however, that an important part of the overall development of a computational simulation initiative is the feedback provided to model developers and analysts associated with the application. (2) We utilize information obtained for the calibration of model parameters to estimate the parameters and quantify uncertainty in the estimates. We rely, however, on validation data (or data from similar analyses) to measure the variability that contributes to the uncertainty in predictions for specific systems or units (unit-to-unit variability). (3) We perform statistical

  13. External validation of the ability of the DRAGON score to predict outcome after thrombolysis treatment

    DEFF Research Database (Denmark)

    Ovesen, Christian Aavang; Christensen, Anders; Nielsen, J K

    2013-01-01

    Easy-to-perform and valid assessment scales for the effect of thrombolysis are essential in hyperacute stroke settings. Because of this we performed an external validation of the DRAGON scale proposed by Strbian et al. in a Danish cohort. All patients treated with intravenous recombinant plasmino......Easy-to-perform and valid assessment scales for the effect of thrombolysis are essential in hyperacute stroke settings. Because of this we performed an external validation of the DRAGON scale proposed by Strbian et al. in a Danish cohort. All patients treated with intravenous recombinant...... and their modified Rankin Scale (mRS) was assessed after 3 months. Three hundred and three patients were included in the analysis. The DRAGON scale proved to have a good discriminative ability for predicting highly unfavourable outcome (mRS 5-6) (area under the curve-receiver operating characteristic [AUC-ROC]: 0...

  14. Validity of the Obsessive Compulsive Drinking Scale (OCDS): does craving predict drinking behavior?

    Science.gov (United States)

    Kranzler, H R; Mulgrew, C L; Modesto-Lowe, V; Burleson, J A

    1999-01-01

    The Obsessive Compulsive Drinking Scale (OCDS), a 14-item, self-report questionnaire, was developed to measure alcohol-related craving. The OCDS may provide a measure of the state of illness among alcohol-dependent individuals and may have value in predicting subsequent drinking behavior. The present study was conducted to evaluate the factor structure and the concurrent, construct, and predictive validity of the OCDS. Data on desire to drink and on drinking behavior were obtained from 127 alcohol-dependent subjects who participated in a 12-week outpatient pharmacotherapy trial and a 3-month posttreatment follow-up. Principal components analysis of the OCDS indicated that three factors best described its structure: obsessions, drinking control and consequences, and alcohol consumption. Data also supported the concurrent and discriminant validity of the OCDS. However, the OCDS total score showed limited validity in predicting drinking during a posttreatment follow-up period. Furthermore, the only empirically derived factor that predicted drinking during this period was the alcohol consumption factor. As might be expected, the OCDS questions on drinking behavior predict subsequent drinking behavior. However, the instrument does not appear to provide a general measure of alcohol-related illness. The utility of the OCDS in studies of alcoholism treatment outcome requires clearer definition.

  15. Low self-esteem prospectively predicts depression in the transition to young adulthood: A replication of Orth, Robins, and Roberts (2008).

    Science.gov (United States)

    Rieger, Sven; Göllner, Richard; Trautwein, Ulrich; Roberts, Brent W

    2016-01-01

    The present study is a close replication of the work of Orth, Robins, and Roberts (2008). Orth et al. (2008) tested three theoretical models of the relation between self-esteem and depression--the vulnerability model, the scar model, and the common factor model--using longitudinal, cross-lagged panel designs. The authors concluded that depression and self-esteem were not the same construct (contrary to the common-factor model), and furthermore, the results were clearly in line with the vulnerability model and not with the scar model (low self-esteem predicts subsequent levels of depression and not vice versa). In addition, the results held for both men and women. To conduct a very close replication of the work of Orth et al. (2008), we used data from another large longitudinal study (N = 2,512), which is highly similar in study design and that contains the same measures (self-esteem and depression). The present study replicated the results of the Orth et al. (2008) study in a notable manner, in regard to the comparability of the coefficients, and therefore, corroborates the vulnerability model (and not the scar- or the common-factor model).

  16. Validation of a method to predict hammer speed from cable force

    Institute of Scientific and Technical Information of China (English)

    Sara M. Brice; Kevin F. Ness; Doug Rosemond

    2015-01-01

    Purpose: The purpose of this study was to develop and validate a method that would facilitate immediate feedback on linear hammer speed during training. Methods:Three-dimensional hammer head positional data were measured and used to calculate linear speed (calculated speed) and cable force. These data were used to develop two linear regression models (shifted and non-shifted) that would allow prediction of hammer speed from measured cable force data (predicted speed). The accuracy of the two models was assessed by comparing the predicted and calculated speeds. Averages of the coefficient of multiple correlation (CMC) and the root mean square (RMS) of the difference between the predicted and calculated speeds for each throw of each participant were used to assess the level of accuracy of the predicted speeds. Results:Both regression models had high CMC values (0.96 and 0.97) and relatively low RMS values (1.27 m/s and 1.05 m/s) for the non-shifted and shifted models, respectively. In addition, the average percentage differences between the predicted and calculated speeds were 6.6%and 4.7%for the non-shifted and shifted models, respectively. The RMS differences between release speeds attained via the two regression models and those attained via three-dimensional positional data were also computed. The RMS differences between the predicted and calculated release speeds were 0.69 m/s and 0.46 m/s for the non-shifted and shifted models, respectively. Conclusion:This study successfully derived and validated a method that allows prediction of linear hammer speed from directly measured cable force data. Two linear regression models were developed and it was found that either model would be capable of predicting accurate speeds. However, data predicted using the shifted regression model were more accurate.

  17. Prediction of the thermal decomposition of organic peroxides by validated QSPR models

    Energy Technology Data Exchange (ETDEWEB)

    Prana, Vinca [Institut de Recherche de Chimie Paris, Chimie ParisTech CNRS, 11 rue P. et M. Curie, Paris 75005 (France); Institut National de l’Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP2, Verneuil-en-Halatte 60550 (France); Rotureau, Patricia, E-mail: patricia.rotureau@ineris.fr [Institut National de l’Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP2, Verneuil-en-Halatte 60550 (France); Fayet, Guillaume [Institut National de l’Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP2, Verneuil-en-Halatte 60550 (France); André, David; Hub, Serge [ARKEMA, rue Henri Moissan, BP63, Pierre Benite 69493 (France); Vicot, Patricia [Institut National de l’Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP2, Verneuil-en-Halatte 60550 (France); Rao, Li [Institut de Recherche de Chimie Paris, Chimie ParisTech CNRS, 11 rue P. et M. Curie, Paris 75005 (France); Adamo, Carlo [Institut de Recherche de Chimie Paris, Chimie ParisTech CNRS, 11 rue P. et M. Curie, Paris 75005 (France); Institut Universitaire de France, 103 Boulevard Saint Michel, Paris F-75005 (France)

    2014-07-15

    Highlights: • QSPR models were developed for thermal stability of organic peroxides. • Two accurate MLR models were exhibited based on quantum chemical descriptors. • Performances were evaluated by a series of internal and external validations. • The new QSPR models satisfied all OCDE principles of validation for regulatory use. - Abstract: Organic peroxides are unstable chemicals which can easily decompose and may lead to explosion. Such a process can be characterized by physico-chemical parameters such as heat and temperature of decomposition, whose determination is crucial to manage related hazards. These thermal stability properties are also required within many regulatory frameworks related to chemicals in order to assess their hazardous properties. In this work, new quantitative structure–property relationships (QSPR) models were developed to predict accurately the thermal stability of organic peroxides from their molecular structure respecting the OECD guidelines for regulatory acceptability of QSPRs. Based on the acquisition of 38 reference experimental data using DSC (differential scanning calorimetry) apparatus in homogenous experimental conditions, multi-linear models were derived for the prediction of the decomposition heat and the onset temperature using different types of molecular descriptors. Models were tested by internal and external validation tests and their applicability domains were defined and analyzed. Being rigorously validated, they presented the best performances in terms of fitting, robustness and predictive power and the descriptors used in these models were linked to the peroxide bond whose breaking represents the main decomposition mechanism of organic peroxides.

  18. Validity of the UKCAT in applicant selection and predicting exam performance in UK dental students.

    Science.gov (United States)

    Lala, Rizwana; Wood, Duncan; Baker, Sarah

    2013-09-01

    The United Kingdom's Clinical Aptitude Test (UKCAT) aims to assess candidates' "natural talent" for dentistry. The aim of this study was to determine the validity of the UKCAT for dental school applicant selection. The relationship of the UKCAT with demographic and academic variables was examined, assessing if the likelihood of being offered a place at a UK dental school was predicted by demographic factors and academic selection tools (predicted grades and existing school results). Finally, the validity of these selection tools in predicting first-year dental exam performance was assessed. Correlational and regression analyses showed that females and poorer students were more likely to have lower UKCAT scores. Gender and social class did not, however, predict first-year dental exam performance. UKCAT scores predicted the likelihood of the candidate being offered a place in the dental course; however, they did not predict exam performance during the first year of the course. Indeed, the only predictor of dental exam performance was existing school results. These findings argue against the use of the UKCAT as the sole determinant in dental applicant selection, instead highlighting the value of using existing school results.

  19. Predictive validity of the UPDRS postural stability score and the Functional Reach Test, when compared with ecologically valid reaching tasks.

    Science.gov (United States)

    Jenkins, M E; Johnson, A M; Holmes, J D; Stephenson, F F; Spaulding, S J

    2010-07-01

    Balance problems and falls are a common concern among individuals with Parkinson's disease (PD). Falls frequently occur during daily activities such as reaching into cupboards in the kitchen or bathroom. This study compared the correlation among two standard postural stability tests - the postural stability score on the Unified Parkinson's Disease Rating Scale (UPDRS) and the Functional Reach Test (FRT) - and ecologically valid reaching tasks that correspond to reaching at different cupboard heights among 20 individuals with PD and 20 age-matched controls. Both the FRT and the UPDRS postural stability tests are quick measures that can be performed during the clinical examination. The FRT, but not the postural stability score, demonstrated a significant correlation with the ecologically valid reaching tasks, among individuals with PD. Furthermore the FRT scores did not correlate with the UPDRS postural stability scores, indicating that these are measuring different aspects of balance. This study suggests that the FRT score may better predict the risk of postural instability encountered during daily activities among individuals with PD.

  20. Validation of the thermophysiological model by Fiala for prediction of local skin temperatures

    Science.gov (United States)

    Martínez, Natividad; Psikuta, Agnes; Kuklane, Kalev; Quesada, José Ignacio Priego; de Anda, Rosa María Cibrián Ortiz; Soriano, Pedro Pérez; Palmer, Rosario Salvador; Corberán, José Miguel; Rossi, René Michel; Annaheim, Simon

    2016-12-01

    The most complete and realistic physiological data are derived from direct measurements during human experiments; however, they present some limitations such as ethical concerns, time and cost burden. Thermophysiological models are able to predict human thermal response in a wide range of environmental conditions, but their use is limited due to lack of validation. The aim of this work was to validate the thermophysiological model by Fiala for prediction of local skin temperatures against a dedicated database containing 43 different human experiments representing a wide range of conditions. The validation was conducted based on root-mean-square deviation (rmsd) and bias. The thermophysiological model by Fiala showed a good precision when predicting core and mean skin temperature (rmsd 0.26 and 0.92 °C, respectively) and also local skin temperatures for most body sites (average rmsd for local skin temperatures 1.32 °C). However, an increased deviation of the predictions was observed for the forehead skin temperature (rmsd of 1.63 °C) and for the thigh during exercising exposures (rmsd of 1.41 °C). Possible reasons for the observed deviations are lack of information on measurement circumstances (hair, head coverage interference) or an overestimation of the sweat evaporative cooling capacity for the head and thigh, respectively. This work has highlighted the importance of collecting details about the clothing worn and how and where the sensors were attached to the skin for achieving more precise results in the simulations.

  1. Validation that Metabolic Tumor Volume Predicts Outcome in Head and Neck Cancer

    Science.gov (United States)

    Tang, Chad; Murphy, James D.; Khong, Brian; La, Trang H.; Kong, Christina; Fischbein, Nancy J.; Colevas, A. Dimitrios; Iagaru, Andrei H.; Graves, Edward E.; Loo, Billy W.; Le, Quynh-Thu

    2011-01-01

    Purpose We have previously reported that metabolic tumor volume (MTV) obtained from pre-treatment FDG PET/CT predicted outcome in patients with head-and-neck cancer (HNC). The purpose of this study is to validate these results on an independent dataset, determine if the primary tumor or nodal MTV drives this correlation, and explore the interaction with p16INK4a status as a surrogate marker for HPV. Methods and Materials The validation dataset in this study included 83 patients with squamous cell HNC who had a FDG PET/CT scan prior to definitive radiotherapy. MTV and SUVmax were calculated for the primary tumor, involved nodes, and the combination of both. The primary endpoint was to validate that MTV predicted progression-free survival and overall survival. Secondary analyses included determining the prognostic utility of primary tumor versus nodal MTV. Results Similar to our prior findings, an increase in total MTV of 17 cm3 (difference between 75th and 25th percentile) was associated with a 2.1 fold increase in the risk of disease progression (p=0.0002), and a 2.0 fold increase in the risk of death (p=0.0048). SUVmax was not associated with either outcome. Primary tumor MTV predicted progression-free (HR=1.94; p<0.0001) and overall (HR=1.57; p<0.0001) survival, whereas nodal MTV did not. In addition, MTV predicted progression-free (HR=4.23; p<0.0001) and overall (HR=3.21; p=0.0029) survival in patients with p16INK4a positive oropharyngeal cancer. Conclusions This study validates our previous findings that MTV independently predicts outcomes in HNC. MTV should be considered as a potential risk stratifying biomarker in future studies of HNC. PMID:22270174

  2. Database Replication

    CERN Document Server

    Kemme, Bettina

    2010-01-01

    Database replication is widely used for fault-tolerance, scalability and performance. The failure of one database replica does not stop the system from working as available replicas can take over the tasks of the failed replica. Scalability can be achieved by distributing the load across all replicas, and adding new replicas should the load increase. Finally, database replication can provide fast local access, even if clients are geographically distributed clients, if data copies are located close to clients. Despite its advantages, replication is not a straightforward technique to apply, and

  3. Prediction of treatment outcome in social phobia: a cross-validation.

    Science.gov (United States)

    Scholing, A; Emmelkamp, P M

    1999-07-01

    This study was a replication of a study on the prediction of treatment outcome in social phobic patients [Chambless, D. L., Tran, G. Q. Glass, C.R. (1997). Predictors of response to cognitive-behavioral group therapy for social phobia. Journal of Anxiety Disorders, 11 221-240]. Results at the posttest and the 18-months follow-up were analyzed for DSM-III-R social phobic patients, with either a generalized social phobia (n = 50) or a nongeneralized fear, i.e. fear of blushing, trembling or sweating in social situations (n = 26). Predictors were pretreatment depression, personality disorder traits, clinician rated severity of impairment and frequency of negative self-statements during social interactions. The criterium variable was (the residual gain score of) self-reported avoidance of social situations. In line with Chambless et al., pretreatment depression showed some predictive value, but smaller and only at the posttest. Change in the frequency of negative self-statements paralleled, but did not predict, change in social phobia symptoms. In contrast with Chambless et al., clinician rated severity was (slightly) predictive for treatment outcome, whereas avoidant personality traits had reverse correlations with outcome in both subgroups. The results are discussed and directions for further research are given.

  4. The Validity of Conscientiousness Is Overestimated in the Prediction of Job Performance.

    Directory of Open Access Journals (Sweden)

    Sven Kepes

    Full Text Available Sensitivity analyses refer to investigations of the degree to which the results of a meta-analysis remain stable when conditions of the data or the analysis change. To the extent that results remain stable, one can refer to them as robust. Sensitivity analyses are rarely conducted in the organizational science literature. Despite conscientiousness being a valued predictor in employment selection, sensitivity analyses have not been conducted with respect to meta-analytic estimates of the correlation (i.e., validity between conscientiousness and job performance.To address this deficiency, we reanalyzed the largest collection of conscientiousness validity data in the personnel selection literature and conducted a variety of sensitivity analyses.Publication bias analyses demonstrated that the validity of conscientiousness is moderately overestimated (by around 30%; a correlation difference of about .06. The misestimation of the validity appears to be due primarily to suppression of small effects sizes in the journal literature. These inflated validity estimates result in an overestimate of the dollar utility of personnel selection by millions of dollars and should be of considerable concern for organizations.The fields of management and applied psychology seldom conduct sensitivity analyses. Through the use of sensitivity analyses, this paper documents that the existing literature overestimates the validity of conscientiousness in the prediction of job performance. Our data show that effect sizes from journal articles are largely responsible for this overestimation.

  5. Using deuterated PAH amendments to validate chemical extraction methods to predict PAH bioavailability in soils

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Eyles, Jose L., E-mail: j.l.gomezeyles@reading.ac.uk [University of Reading, School of Human and Environmental Sciences, Soil Research Centre, Reading, RG6 6DW Berkshire (United Kingdom); Collins, Chris D.; Hodson, Mark E. [University of Reading, School of Human and Environmental Sciences, Soil Research Centre, Reading, RG6 6DW Berkshire (United Kingdom)

    2011-04-15

    Validating chemical methods to predict bioavailable fractions of polycyclic aromatic hydrocarbons (PAHs) by comparison with accumulation bioassays is problematic. Concentrations accumulated in soil organisms not only depend on the bioavailable fraction but also on contaminant properties. A historically contaminated soil was freshly spiked with deuterated PAHs (dPAHs). dPAHs have a similar fate to their respective undeuterated analogues, so chemical methods that give good indications of bioavailability should extract the fresh more readily available dPAHs and historic more recalcitrant PAHs in similar proportions to those in which they are accumulated in the tissues of test organisms. Cyclodextrin and butanol extractions predicted the bioavailable fraction for earthworms (Eisenia fetida) and plants (Lolium multiflorum) better than the exhaustive extraction. The PAHs accumulated by earthworms had a larger dPAH:PAH ratio than that predicted by chemical methods. The isotope ratio method described here provides an effective way of evaluating other chemical methods to predict bioavailability. - Research highlights: > Isotope ratios can be used to evaluate chemical methods to predict bioavailability. > Chemical methods predicted bioavailability better than exhaustive extractions. > Bioavailability to earthworms was still far from that predicted by chemical methods. - A novel method using isotope ratios to assess the ability of chemical methods to predict PAH bioavailability to soil biota.

  6. Predictive validity of the MMPI-2 clinical, PSY-5, and RC scales for therapy disruptive behavior.

    Science.gov (United States)

    Scholte, Wubbo; Tiemens, Bea G; Verheul, Roel; Meerman, Anke; Egger, Jos; Hutschemaekers, Giel

    2012-11-01

    Impulsive acts, parasuicidal behavior, and other therapy disruptive incidents occur frequently in the treatment of patients with personality disorders and increase the risk that patients will drop out of treatment. This study examined the predictive validity of the Minnesota Multiphasic Personality Inventory (MMPI)-2 Restructured Clinical (RC) and Psychopathology Five (PSY-5) Scales for therapy disruptive behavior and compared them with the original clinical scales. Using an inventory, the treatment staff recorded the therapy disruptive behavior of 104 patients with personality disorders who were receiving inpatient psychotherapy. Both the RC and the PSY-5 scales predicted several categories of therapy disruptive behavior, and both scales predicted more categories of therapy disruptive behavior than the original clinical scales. Anger outbursts were predicted especially well by a combination of two of the RC scales. The information about the MMPI-2 obtained in this study may be helpful in case formulation when initiating inpatient treatment for patients with personality disorders.

  7. Predicting complications in pre-eclampsia : external validation of the fullPIERS model using the PETRA trial dataset

    NARCIS (Netherlands)

    Akkermans, Joost; Payne, Beth; von Dadelszen, Peter; Groen, Henk; de Vries, Johanna; Magee, Laura A.; Mol, Ben Willem; Ganzevoort, Wessel

    2014-01-01

    Objective: The internally validated fulIPIERS model predicts adverse maternal outcomes in women with pre-eclampsia within 48 h after eligibility. Our objective was to assess generalizability of this prediction model. Study design: External validation study using prospectively collected data from two

  8. Analyzing Multiple Informant Data on Child and Adolescent Behavior Problems: Predictive Validity and Comparison of Aggregation Procedures

    Science.gov (United States)

    van Dulmen, Manfred H. M.; Egeland, Byron

    2011-01-01

    We compared the predictive validity of five aggregation methods for multiple informant data on child and adolescent behavior problems. In addition, we compared the predictive validity of these aggregation methods with single informant scores. Data were derived from the Minnesota Longitudinal Study of Parents and Children (N = 175). Maternal and…

  9. Verification and validation of the simulated radar image (SRIM) code radar cross section predictions

    Science.gov (United States)

    Stanley, Dale A.

    1991-12-01

    The objectives of this study were to verify and validate the Simulated Radar Image (SRIM) Code Version 4.0 monostatic radar cross section (RCS) predictions. SRIM, uses the theory of Physical Optics (PO) to predict backscatter for a user specified aspect angle. Target obscuration and multiple reflections are taken into account by sampling the target with ray tracing. The software verification and validation technique followed in this study entailed comparing the code predictions to closed form PO equations, other RCS prediction software packages, and measured data. The targets analyzed were a sphere, rectangular flat plate, circular flat plate, solid right circular cylinder, dihedral and trihedral corner reflectors, top hat, cone, prolate spheroid, and generic missile. SRIM RCS predictions are shown for each target as a function of frequency, aspect angle, and ray density. Also presented is an automation technique that enables the user to run SRIM sequentially over a range of azimuth angles. The FORTRAN code written by the author for the PO equations is also provided.

  10. Comparing predictive validity of four ballistic swing phase models of human walking.

    Science.gov (United States)

    Selles, R W; Bussmann, J B; Wagenaar, R C; Stam, H J

    2001-09-01

    It is unclear to what extent ballistic walking models can be used to qualitatively predict the swing phase at comfortable walking speed. Different study findings regarding the accuracy of the predictions of the swing phase kinematics may have been caused by differences in (1) kinematic input, (2) model characteristics (e.g. the number of segments), and (3) evaluation criteria. In the present study, the predictive validity of four ballistic swing phase models was evaluated and compared, that is, (1) the ballistic walking model as originally introduced by Mochon and McMahon, (2) an extended version of this model in which heel-off of the stance leg is added, (3) a double pendulum model, consisting of a two-segment swing leg with a prescribed hip trajectory, and (4) a shank pendulum model consisting of a shank and rigidly attached foot with a prescribed knee trajectory. The predictive validity was evaluated by comparing the outcome of the model simulations with experimentally derived swing phase kinematics of six healthy subjects. In all models, statistically significant differences were found between model output and experimental data. All models underestimated swing time and step length. In addition, statistically significant differences were found between the output of the different models. The present study shows that although qualitative similarities exist between the ballistic models and normal gait at comfortable walking speed, these models cannot adequately predict swing phase kinematics.

  11. Development and validation of a dynamic outcome prediction model for paracetamol-induced acute liver failure

    DEFF Research Database (Denmark)

    Bernal, William; Wang, Yanzhong; Maggs, James

    2016-01-01

    BACKGROUND: Early, accurate prediction of survival is central to management of patients with paracetamol-induced acute liver failure to identify those needing emergency liver transplantation. Current prognostic tools are confounded by recent improvements in outcome independent of emergency liver ...... in paracetamol-induced acute liver failure require re-evaluation. FUNDING: Foundation for Liver Research. Copyright © 2016 Elsevier Ltd. All rights reserved....... normalised ratio (INR), and cardiovascular failure were used to derive an initial predictive model, with a second (day 2) model including additional changes in INR and lactate. FINDINGS: We developed and validated new high-performance statistical models to support decision making in patients with paracetamol...

  12. The derivation and validation of a prediction rule for differential diagnosis of thyroid nodules

    Institute of Scientific and Technical Information of China (English)

    李拓

    2013-01-01

    Objective To set up a prediction rule for the pro-operative differential diagnosis of thyroid nodules and evaluate its clinical value.Methods All patients of thyroid nodules undergoing thyroid operations in Changzheng hospital from June,1997 to July,2012 were included in this study.They were randomly divided into the derivation cohort (2/3) and the validation cohort (1/3) .A prediction rule was developed based on the logistic regression model and the scoring system was established in accordance with assigning of the value of each variableβ

  13. The Predictive Validity of the Structured Assessment of Violence Risk in Youth for Young Spanish Offenders.

    Science.gov (United States)

    Ortega-Campos, Elena; García-García, Juan; Zaldívar-Basurto, Flor

    2017-01-01

    The present study examined the predictive validity of the Structured Assessment of Violence Risk in Youth (SAVRY) in a group of young Spanish offenders. The sample is made up of 594 minors from the Juvenile Court, between the ages of 14 and 18 at the time they committed the delinquent act. The SAVRY was able to differentiate between low and high-risk younger offenders. Mean scores on risk factor are greater in the group of recidivist offenders, the group of non-recidivist shows higher mean scores in Protective domain. The accuracy of the instrument is high (AUCRiskTotalScore = 0.737 and AUCSummaryRiskRating = 0.748). An approximation of the predictive validity study of the SAVRY in Spanish younger offenders is presented. The results obtained support the SAVRY good functioning with not English samples.

  14. Predictive Validity of Pressure Ulcer Risk Assessment Tools for Elderly: A Meta-Analysis.

    Science.gov (United States)

    Park, Seong-Hi; Lee, Young-Shin; Kwon, Young-Mi

    2016-04-01

    Preventing pressure ulcers is one of the most challenging goals existing for today's health care provider. Currently used tools which assess risk of pressure ulcer development rarely evaluate the accuracy of predictability, especially in older adults. The current study aimed at providing a systemic review and meta-analysis of 29 studies using three pressure ulcer risk assessment tools: Braden, Norton, and Waterlow Scales. Overall predictive validities of pressure ulcer risks in the pooled sensitivity and specificity indicated a similar range with a moderate accuracy level in all three scales, while heterogeneity showed more than 80% variability among studies. The studies applying the Braden Scale used five different cut-off points representing the primary cause of heterogeneity. Results indicate that commonly used screening tools for pressure ulcer risk have limitations regarding validity and accuracy for use with older adults due to heterogeneity among studies.

  15. The predictive validity of the survey of readiness for alcoholics anonymous participation.

    Science.gov (United States)

    Kingree, Jeffrey B; Simpson, Alpha; Thompson, Martie; McCrady, Barbara; Tonigan, J Scott

    2007-01-01

    This study evaluated the predictive validity of the Survey of Readiness for Alcoholics Anonymous Participation (SYRAAP), which is a 15-item, self-administered instrument. Bivariate and multivariate analyses examined whether responses to the SYRAAP within 1 week of entering substance-use treatment (T1) were associated with posttreatment Alcoholics Anonymous (AA) participation at 3-month (T2) and 6-month (T3) follow-up assessments. The T1 assessment was completed by 268 respondents; the T2 and T3 assessments were completed by 232 (86%) and 217 (81%) respondents, respectively. Results revealed that responses to the SYRAAP at T1 predicted AA participation at T2 and T3. The findings indicate the SYRAAP is a valid measure for assessing readiness for participating in AA. Future research in relation to the SYRAAP and limitations of the current study are discussed.

  16. New enhancements and validation of force based posture and discomfort predictions.

    Science.gov (United States)

    Wirsching, Hans-Joachim; Engstler, Florian

    2012-01-01

    Many digital human models provide the crucial method to calculate postures in virtual environments. Traditionally these methods refer to experiments and make use of statistical modeling. They provide sufficient results in their specialized domain, but cannot be used in general applications. In addition they do not consider important design aspects as forces and discomfort. Hence a new force based approach has been introduced in order to overcome these shortcomings. Based on biomechanical models of active maximal and passive receding joint torques, a mechanical optimization generates static stable postures and related discomfort ratings. The results were promising, but showed some model deficiencies and were not validated in detail. The present paper continues this work and provides necessary model enhancements. Finally the new prediction models are validated on real experiments. The validation results are presented and discussed regarding to usability aspects and future development work.

  17. Predictive validity of a non-induced mouse model of compulsive-like behavior.

    Science.gov (United States)

    Greene-Schloesser, D M; Van der Zee, E A; Sheppard, D K; Castillo, M R; Gregg, K A; Burrow, T; Foltz, H; Slater, M; Bult-Ito, A

    2011-08-01

    A key to advancing the understanding of obsessive-compulsive disorder (OCD)-like symptoms is the development of spontaneous animal models. Over 55 generations of bidirectional selection for nest-building behavior in house mice, Mus musculus, resulted in a 40-fold difference in the amount of cotton used for a nest in high (BIG) and low (SMALL) selected lines. The nesting behavior of BIG mice appears to be compulsive-like and has initial face validity as an animal model for OCD in humans. Compulsive-like digging behavior was assessed; BIG male mice buried about three times as many marbles as SMALL male mice, strengthening face validity. Using the open field and elevated plus maze, SMALL male mice showed higher levels of anxiety/fear-like behavior than BIG male mice, indicating that compulsive-like and not anxiety-like behavior was measured. To establish predictive validity, chronic (4 weeks) oral administration of fluoxetine (30, 50 and 100mg/kg/day) and clomipramine (80 mg/kg/day), both effective in treating OCD, significantly reduced compulsive-like nest-building behavior in BIG male mice. Compulsive-like digging behavior was also significantly reduced by chronic oral fluoxetine (30 and 80 mg/kg/day) treatment in BIG male mice. General locomotor activity was not affected by chronic oral fluoxetine (30 and 80 mg/kg/day) treatment; chronic oral treatment with desipramine (30 mg/kg/day), an antidepressant not effective in treating OCD, had no effect on nesting behavior of BIG male mice, strengthening predictive validity. Together, the results indicate that these mice have good face and predictive validity as a non-induced mouse model of compulsive-like behavior relevant to OCD.

  18. Validation of a multi-marker model for the prediction of incident type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Lyssenko, Valeriya; Jørgensen, Torben; Gerwien, Robert W;

    2012-01-01

    .0001). In time to event analysis, rates of conversion to diabetes in low, moderate, and high DRS groups were significantly different (p 2DM risk than other methods.......Purpose: To assess performance of a biomarker-based score that predicts the five-year risk of diabetes (Diabetes Risk Score, DRS) in an independent cohort that included 15-year follow-up. Method: DRS was developed on the Inter99 cohort, and validated on the Botnia cohort. Performance...

  19. A Predictive Validity Study of an Assessment Center for Research and Development Supervisors.

    Science.gov (United States)

    1981-09-01

    where aplicable , alprorriate self developmental activities that might be warranted. These objectives were used as guidelines in the design of the...Sciences ( SPSS ) (Nie et al, 1975). The Aeronautical Systems Division CDC 6600 computer was used to run all required programs. Previous Studies There has...with the excention of SU,’DIIU) using the SPSS subprogram ?BASON CCRR. 3ubgroun Data Analysis Predictive validity technioues used for the overall sam cle

  20. Advanced validation of CFD-FDTD combined method using highly applicable solver for reentry blackout prediction

    OpenAIRE

    Takahashi, Yusuke

    2015-01-01

    An analysis model of plasma flow and electromagnetic waves around a reentry vehicle for radio frequency blackout prediction during aerodynamic heating was developed in this study. The model was validated based on experimental results from the radio attenuation measurement program. The plasma flow properties, such as electron number density, in the shock layer and wake region were obtained using a newly developed unstructured grid solver that incorporated real gas effect models ...

  1. Valuing structured professional judgment: predictive validity, decision-making, and the clinical-actuarial conflict.

    Science.gov (United States)

    Falzer, Paul R

    2013-01-01

    Structured professional judgment (SPJ) has received considerable attention as an alternative to unstructured clinical judgment and actuarial assessment, and as a means of resolving their ongoing conflict. However, predictive validity studies have typically relied on receiver operating characteristic (ROC) analysis, the same technique commonly used to validate actuarial assessment tools. This paper presents SPJ as distinct from both unstructured clinical judgment and actuarial assessment. A key distinguishing feature of SPJ is the contribution of modifiable factors, either dynamic or protective, to summary risk ratings. With modifiable factors, the summary rating scheme serves as a prognostic model rather than a classification procedure. However, prognostic models require more extensive and thorough predictive validity testing than can be provided by ROC analysis. It is proposed that validation should include calibration and reclassification techniques, as well as additional measures of discrimination. Several techniques and measures are described and illustrated. The paper concludes by tracing the limitations of ROC analysis to its philosophical foundation and its origin as a statistical theory of decision-making. This foundation inhibits the performance of crucial tasks, such as determining the sufficiency of a risk assessment and examining the evidentiary value of statistical findings. The paper closes by noting a current effort to establish a viable and complementary relationship between SPJ and decision-making theory.

  2. Chinese Frost Multidimensional Perfectionism Scale: a validation and prediction of self-esteem and psychological distress.

    Science.gov (United States)

    Cheng, S K; Chong, G H; Wong, C W

    1999-09-01

    Recent research has shown that perfectionism is an important psychological variable in explaining various disorders. This study evaluated (a) the factor structure and psychometric properties of the Chinese Frost Multidimensional Perfectionism Scale (CFMPS) and (b) the relative predictive power of its subscales for self-esteem and psychological distress, including depressive, anxiety, and stress symptoms. Nine hundred and forty-seven Chinese adolescents from Hong Kong between 13 and 18 years of age participated in the study. Results indicated that five of the original six factors emerged in the factor analysis. The CFMPS and its subscales were found to have satisfactory internal consistencies. Replicating and extending previous findings, the factors "Concern over Mistakes" and "Doubt about Action" accounted for most of the variances of self-esteem and psychological distress. The factor "Organization" might have positive value on psychological health. Possible cultural influence on the development of perfectionism and limitations of the study are discussed.

  3. Pharmaceutical aerosols deposition patterns from a Dry Powder Inhaler: Euler Lagrangian prediction and validation.

    Science.gov (United States)

    Ravi Kannan, Ravishekar; Przekwas, A J; Singh, Narender; Delvadia, Renishkumar; Tian, Geng; Walenga, Ross

    2017-04-01

    This study uses Computational Fluid Dynamics (CFD) to predict, analyze and validate the deposition patterns in a human lung for a Budesonide drug delivered from the Novolizer Dry Powder Inhaler device. We used a test case of known deposition patterns to validate our computational Euler Lagrangian-based deposition predictions. Two different lung models are used: (i) a basic ring-less trachea model and (ii) an advanced Human Zygote5 model. Unlike earlier attempts, the current simulations do not include the device in the computational domain. This greatly reduces the computational effort. To mimic the device, we model the inlet particle jet stream from the device as a spray entering the mouth in a conical fashion. Deposition studies in the various lung regions were performed. We were able to computationally predict and then demonstrate the enhanced deposition in the tracheal and first generation rings/ridges. The enhanced vorticity creation due to the ring structure and the geometrical design contributes to larger deposition in the Zygote5 model. These are in accord with existing data, unlike the ring-less model. Our validated results indicate the need to (i) introduce the ridges in the experimental casts and the CFD surface meshes to be anatomically consistent and obtain physiologically consistent depositions; (ii) introduce a factor to account for the recirculating lighter particles in empirical models.

  4. Predicting relapse among young adults: psychometric validation of the Advanced WArning of RElapse (AWARE) scale.

    Science.gov (United States)

    Kelly, John F; Hoeppner, Bettina B; Urbanoski, Karen A; Slaymaker, Valerie

    2011-10-01

    Failure to maintain abstinence despite incurring severe harm is perhaps the key defining feature of addiction. Relapse prevention strategies have been developed to attenuate this propensity to relapse, but predicting who will, and who will not, relapse has stymied attempts to more efficiently tailor treatments according to relapse risk profile. Here we examine the psychometric properties of a promising relapse risk measure-the Advance WArning of RElapse (AWARE) scale (Miller & Harris, 2000) in an understudied but clinically important sample of young adults. Inpatient youth (N=303; Ages 18-24; 26% female) completed the AWARE scale and the Brief Symptom Inventory-18 (BSI) at the end of residential treatment, and at 1-, 3-, and 6-months following discharge. Internal and convergent validity was tested for each of these four timepoints using confirmatory factor analysis and correlations (with BSI scores). Predictive validity was tested for relapse 1, 3, and 6 months following discharge, as was incremental utility, where AWARE scores were used as predictors of any substance use while controlling for treatment entry substance use severity and having spent time in a controlled environment following treatment. Confirmatory factor analysis revealed a single, internally consistent, 25-item factor that demonstrated convergent validity and predicted subsequent relapse alone and when controlling for other important relapse risk predictors. The AWARE scale may be a useful and efficient clinical tool for assessing short-term relapse risk among young people and, thus, could serve to enhance the effectiveness of relapse prevention efforts. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Measurement of predictive validity in violence risk assessment studies: a second-order systematic review.

    Science.gov (United States)

    Singh, Jay P; Desmarais, Sarah L; Van Dorn, Richard A

    2013-01-01

    The objective of the present review was to examine how predictive validity is analyzed and reported in studies of instruments used to assess violence risk. We reviewed 47 predictive validity studies published between 1990 and 2011 of 25 instruments that were included in two recent systematic reviews. Although all studies reported receiver operating characteristic curve analyses and the area under the curve (AUC) performance indicator, this methodology was defined inconsistently and findings often were misinterpreted. In addition, there was between-study variation in benchmarks used to determine whether AUCs were small, moderate, or large in magnitude. Though virtually all of the included instruments were designed to produce categorical estimates of risk - through the use of either actuarial risk bins or structured professional judgments - only a minority of studies calculated performance indicators for these categorical estimates. In addition to AUCs, other performance indicators, such as correlation coefficients, were reported in 60% of studies, but were infrequently defined or interpreted. An investigation of sources of heterogeneity did not reveal significant variation in reporting practices as a function of risk assessment approach (actuarial vs. structured professional judgment), study authorship, geographic location, type of journal (general vs. specialized audience), sample size, or year of publication. Findings suggest a need for standardization of predictive validity reporting to improve comparison across studies and instruments.

  6. Incremental Validity of Personality Measures in Predicting Underwater Performance and Adaptation.

    Science.gov (United States)

    Colodro, Joaquín; Garcés-de-Los-Fayos, Enrique J; López-García, Juan J; Colodro-Conde, Lucía

    2015-03-17

    Intelligence and personality traits are currently considered effective predictors of human behavior and job performance. However, there are few studies about their relevance in the underwater environment. Data from a sample of military personnel performing scuba diving courses were analyzed with regression techniques, testing the contribution of individual differences and ascertaining the incremental validity of the personality in an environment with extreme psychophysical demands. The results confirmed the incremental validity of personality traits (ΔR 2 = .20, f 2 = .25) over the predictive contribution of general mental ability (ΔR 2 = .07, f 2 = .08) in divers' performance. Moreover, personality (R(L)2 = .34) also showed a higher validity to predict underwater adaptation than general mental ability ( R(L)2 = .09). The ROC curve indicated 86% of the maximum possible discrimination power for the prediction of underwater adaptation, AUC = .86, p personality traits as predictors of an effective response to the changing circumstances of military scuba diving. They also may improve the understanding of the behavioral effects and psychophysiological complications of diving and can also provide guidance for psychological intervention and prevention of risk in this extreme environment.

  7. Quantification of rainfall prediction uncertainties using a cross-validation based technique. Methodology description and experimental validation.

    Science.gov (United States)

    Fraga, Ignacio; Cea, Luis; Puertas, Jerónimo; Salsón, Santiago; Petazzi, Alberto

    2016-04-01

    In this paper we present a new methodology to compute rainfall fields including the quantification of predictions uncertainties using raingauge network data. The proposed methodology comprises two steps. Firstly, the ordinary krigging technique is used to determine the estimated rainfall depth in every point of the study area. Then multiple equi-probable errors fields, which comprise both interpolation and measuring uncertainties, are added to the krigged field resulting in multiple rainfall predictions. To compute these error fields first the standard deviation of the krigging estimation is determined following the cross-validation based procedure described in Delrieu et al. (2014). Then, the standard deviation field is sampled using non-conditioned Gaussian random fields. The proposed methodology was applied to study 7 rain events in a 60x60 km area of the west coast of Galicia, in the Northwest of Spain. Due to its location at the junction between tropical and polar regions, the study area suffers from frequent intense rainfalls characterized by a great variability in terms of both space and time. Rainfall data from the tipping bucket raingauge network operated by MeteoGalicia were used to estimate the rainfall fields using the proposed methodology. The obtained predictions were then validated using rainfall data from 3 additional rain gauges installed within the CAPRI project (Probabilistic flood prediction with high resolution hydrologic models from radar rainfall estimates, funded by the Spanish Ministry of Economy and Competitiveness. Reference CGL2013-46245-R.). Results show that both the mean hyetographs and the peak intensities are correctly predicted. The computed hyetographs present a good fit to the experimental data and most of the measured values fall within the 95% confidence intervals. Also, most of the experimental values outside the confidence bounds correspond to time periods of low rainfall depths, where the inaccuracy of the measuring devices

  8. Chemotherapy effectiveness and mortality prediction in surgically treated osteosarcoma dogs: A validation study.

    Science.gov (United States)

    Schmidt, A F; Nielen, M; Withrow, S J; Selmic, L E; Burton, J H; Klungel, O H; Groenwold, R H H; Kirpensteijn, J

    2016-03-01

    Canine osteosarcoma is the most common bone cancer, and an important cause of mortality and morbidity, in large purebred dogs. Previously we constructed two multivariable models to predict a dog's 5-month or 1-year mortality risk after surgical treatment for osteosarcoma. According to the 5-month model, dogs with a relatively low risk of 5-month mortality benefited most from additional chemotherapy treatment. In the present study, we externally validated these results using an independent cohort study of 794 dogs. External performance of our prediction models showed some disagreement between observed and predicted risk, mean difference: -0.11 (95% confidence interval [95% CI]-0.29; 0.08) for 5-month risk and 0.25 (95%CI 0.10; 0.40) for 1-year mortality risk. After updating the intercept, agreement improved: -0.0004 (95%CI-0.16; 0.16) and -0.002 (95%CI-0.15; 0.15). The chemotherapy by predicted mortality risk interaction (P-value=0.01) showed that the chemotherapy compared to no chemotherapy effectiveness was modified by 5-month mortality risk: dogs with a relatively lower risk of mortality benefited most from additional chemotherapy. Chemotherapy effectiveness on 1-year mortality was not significantly modified by predicted risk (P-value=0.28). In conclusion, this external validation study confirmed that our multivariable risk prediction models can predict a patient's mortality risk and that dogs with a relatively lower risk of 5-month mortality seem to benefit most from chemotherapy.

  9. Accuracy of genome enabled prediction in a dairy cattle population using different cross-validation layouts

    Directory of Open Access Journals (Sweden)

    M. Angeles ePérez-Cabal

    2012-02-01

    Full Text Available The impact of extent of genetic relatedness on accuracy of genome-enabled predictions was assessed using a dairy cattle population and alternative cross-validation (CV strategies were compared. The CV layouts consisted of training and testing sets obtained from either random allocation of individuals (RAN or from a kernel-based clustering of individuals using the additive relationship matrix, to obtain two subsets that were as unrelated as possible (UNREL, as well as a layout based on stratification by generation (GEN. The UNREL layout decreased the average genetic relationships between training and testing animals but produced similar accuracies to the RAN design, which were about 15% higher than in the GEN setting. Results indicate that the CV structure can have an important effect on the accuracy of whole-genome predictions. However, the connection between average genetic relationships across training and testing sets and the estimated predictive ability is not straightforward, and may depend also on the kind of relatedness that exists between the two subsets and on the heritability of the trait. For high heritability traits, close relatives such as parents and full sibs make the greatest contributions to accuracy, which can be compensated by half-sibs or grandsires in the case of lack of close relatives. However, for the low heritability traits the inclusion of close relatives is crucial and including more relatives of various types in the training set tends to lead to greater accuracy. In practice, cross-validation designs should resemble the intended use of the predictive models, e.g. within or between family predictions, or within or across generation predictions, such that estimation of predictive ability is consistent with the actual application to be considered.

  10. Developing and Validating a Survival Prediction Model for NSCLC Patients Through Distributed Learning Across 3 Countries.

    Science.gov (United States)

    Jochems, Arthur; Deist, Timo M; El Naqa, Issam; Kessler, Marc; Mayo, Chuck; Reeves, Jackson; Jolly, Shruti; Matuszak, Martha; Ten Haken, Randall; van Soest, Johan; Oberije, Cary; Faivre-Finn, Corinne; Price, Gareth; de Ruysscher, Dirk; Lambin, Philippe; Dekker, Andre

    2017-10-01

    Tools for survival prediction for non-small cell lung cancer (NSCLC) patients treated with chemoradiation or radiation therapy are of limited quality. In this work, we developed a predictive model of survival at 2 years. The model is based on a large volume of historical patient data and serves as a proof of concept to demonstrate the distributed learning approach. Clinical data from 698 lung cancer patients, treated with curative intent with chemoradiation or radiation therapy alone, were collected and stored at 2 different cancer institutes (559 patients at Maastro clinic (Netherlands) and 139 at Michigan university [United States]). The model was further validated on 196 patients originating from The Christie (United Kingdon). A Bayesian network model was adapted for distributed learning (the animation can be viewed at https://www.youtube.com/watch?v=ZDJFOxpwqEA). Two-year posttreatment survival was chosen as the endpoint. The Maastro clinic cohort data are publicly available at https://www.cancerdata.org/publication/developing-and-validating-survival-prediction-model-nsclc-patients-through-distributed, and the developed models can be found at www.predictcancer.org. Variables included in the final model were T and N category, age, performance status, and total tumor dose. The model has an area under the curve (AUC) of 0.66 on the external validation set and an AUC of 0.62 on a 5-fold cross validation. A model based on the T and N category performed with an AUC of 0.47 on the validation set, significantly worse than our model (P<.001). Learning the model in a centralized or distributed fashion yields a minor difference on the probabilities of the conditional probability tables (0.6%); the discriminative performance of the models on the validation set is similar (P=.26). Distributed learning from federated databases allows learning of predictive models on data originating from multiple institutions while avoiding many of the data-sharing barriers. We believe

  11. Predictive validity of childhood oppositional defiant disorder and conduct disorder: implications for the DSM-V.

    Science.gov (United States)

    Burke, Jeffrey D; Waldman, Irwin; Lahey, Benjamin B

    2010-11-01

    Data are presented from 3 studies of children and adolescents to evaluate the predictive validity of childhood oppositional defiant disorder (ODD) and conduct disorder (CD) as defined in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV; American Psychiatric Association, 1994) and the International Classification of Diseases, Version 10 (ICD-10; World Health Organization, 1992). The present analyses strongly support the predictive validity of these diagnoses by showing that they predict both future psychopathology and enduring functional impairment. Furthermore, the present findings generally support the hierarchical developmental hypothesis in DSM-IV that some children with ODD progress to childhood-onset CD, and some youth with CD progress to antisocial personality disorder (APD). Nonetheless, they reveal that CD does not always co-occur with ODD, particularly during adolescence. Importantly, the present findings suggest that ICD-10 diagnostic criteria for ODD, which treat CD symptoms as ODD symptoms when diagnostic criteria for CD are not met, identify more functionally impaired children than the more restrictive DSM-IV definition of ODD. Filling this "hole" in the DSM-IV criteria for ODD should be a priority for the DSM-V. In addition, the present findings suggest that although the psychopathic trait of interpersonal callousness in childhood independently predicts future APD, these findings do not confirm the hypothesis that callousness distinguishes a subset of children with CD with an elevated risk for APD.

  12. Self-discrepancy: Long-term test-retest reliability and test-criterion predictive validity.

    Science.gov (United States)

    Watson, Neill; Bryan, Brandon C; Thrash, Todd M

    2016-01-01

    Long-term test-retest reliability and predictive test-criterion evidence of validity of scores on measures of the real-ideal self-discrepancy and of the real-ought self-discrepancy were tested over periods of 1 year and 3 years. A sample of 184 undergraduates completed at 2 time points 1 year apart 3 instruments that each measure the 2 self-discrepancies: the idiographic Self-Concept Questionnaire-Personal Constructs, the nonidiographic Self-Concept Questionnaire-Conventional Constructs, and the content-free Abstract Measures. A separate sample of 141 undergraduates completed the instruments 3 years apart. Both samples completed 3 depression instruments and 3 anxiety instruments at the second time point. Results of analyses using latent variables modeled with 3 observed variables showed substantial statistically significant test-retest reliabilities and significant test-criterion prediction of anxiety and depression on the real-ideal and real-ought discrepancy measures over both time periods. Results for the observed variables showed significant 1-year and 3-year reliabilities for scores on all self-discrepancy measures, as well as significant 1-year and 3-year predictive validity for scores on all self-discrepancy measures, except the abstract measure of real-ought discrepancy in predicting scores on all depression measures and on at least 1 anxiety measure. The findings support very strong long-term stabilities of the self-discrepancy personality constructs and their long-term associations with anxiety and depression.

  13. Validations and improvements of airfoil trailing-edge noise prediction models using detailed experimental data

    DEFF Research Database (Denmark)

    Kamruzzaman, M.; Lutz, Th.; Würz, W.;

    2012-01-01

    -layer properties such as two-point turbulent velocity correlations, the spectra of the associated wall pressure fluctuations and the emitted trailing-edge far-field noise were performed in the laminar wind tunnel of the Institute of Aerodynamics and Gas Dynamics, University of Stuttgart. The measurements were...... carried out for a NACA 643-418 airfoil, at Re  =  2.5 ×106, angle of attack of −6° to 6°. Numerical results of different prediction schemes are extensively validated and discussed elaborately. The investigations on the TNO-Blake noise prediction model show that the numerical wall pressure fluctuation...... with measurements in the frequency region higher than 1 kHz, whereas they over-predict the sound pressure level in the low-frequency region. Copyright © 2011 John Wiley & Sons, Ltd....

  14. Ab initio prediction of the polymorphic structures of pyrazinamide: A validation study

    Directory of Open Access Journals (Sweden)

    David Stephen Arputhara

    2016-01-01

    Full Text Available A validation study to predict the possible stable polymorphs of Pyrazinamide within a low energy conformational region of the flexible torsion angle was made through a potential energy surface (PES scan by gas phase optimisation using the MP2/6-31G(d,p method. Hypothetical crystal structures with favourable packing density for each of the stable conformers generated from the PES scan were generated using a global search with a repulsion only potential field. The densest crystal structures with stable energy were analyzed with more accurate lattice energy minimisation via distributed multipole analysis using a repulsion-dispersion potential. The stability of the predicted crystal structures with similar close packing to the known experimental polymorphs of Pyrazinamide molecule was analyzed by inspecting their intermolecular short contacts. Studies to analyze the second derivative mechanical properties from the hessian matrix were carried out to emphasise the thermodynamic stability of predicted polymorphs of Pyrazinamide.

  15. Predicting survival in malignant pleural effusion: development and validation of the LENT prognostic score.

    Science.gov (United States)

    Clive, Amelia O; Kahan, Brennan C; Hooper, Clare E; Bhatnagar, Rahul; Morley, Anna J; Zahan-Evans, Natalie; Bintcliffe, Oliver J; Boshuizen, Rogier C; Fysh, Edward T H; Tobin, Claire L; Medford, Andrew R L; Harvey, John E; van den Heuvel, Michel M; Lee, Y C Gary; Maskell, Nick A

    2014-12-01

    Malignant pleural effusion (MPE) causes debilitating breathlessness and predicting survival is challenging. This study aimed to obtain contemporary data on survival by underlying tumour type in patients with MPE, identify prognostic indicators of overall survival and develop and validate a prognostic scoring system. Three large international cohorts of patients with MPE were used to calculate survival by cell type (univariable Cox model). The prognostic value of 14 predefined variables was evaluated in the most complete data set (multivariable Cox model). A clinical prognostic scoring system was then developed and validated. Based on the results of the international data and the multivariable survival analysis, the LENT prognostic score (pleural fluid lactate dehydrogenase, Eastern Cooperative Oncology Group (ECOG) performance score (PS), neutrophil-to-lymphocyte ratio and tumour type) was developed and subsequently validated using an independent data set. Risk stratifying patients into low-risk, moderate-risk and high-risk groups gave median (IQR) survivals of 319 days (228-549; n=43), 130 days (47-467; n=129) and 44 days (22-77; n=31), respectively. Only 65% (20/31) of patients with a high-risk LENT score survived 1 month from diagnosis and just 3% (1/31) survived 6 months. Analysis of the area under the receiver operating curve revealed the LENT score to be superior at predicting survival compared with ECOG PS at 1 month (0.77 vs 0.66, pLENT scoring system is the first validated prognostic score in MPE, which predicts survival with significantly better accuracy than ECOG PS alone. This may aid clinical decision making in this diverse patient population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  16. Using sensitivity analysis to validate the predictions of a biomechanical model of bite forces.

    Science.gov (United States)

    Sellers, William Irvin; Crompton, Robin Huw

    2004-02-01

    Biomechanical modelling has become a very popular technique for investigating functional anatomy. Modern computer simulation packages make producing such models straightforward and it is tempting to take the results produced at face value. However the predictions of a simulation are only valid when both the model and the input parameters are accurate and little work has been done to verify this. In this paper a model of the human jaw is produced and a sensitivity analysis is performed to validate the results. The model is built using the ADAMS multibody dynamic simulation package incorporating the major occlusive muscles of mastication (temporalis, masseter, medial and lateral pterygoids) as well as a highly mobile temporomandibular joint. This model is used to predict the peak three-dimensional bite forces at each teeth location, joint reaction forces, and the contributions made by each individual muscle. The results for occlusive bite-force (1080N at M1) match those previously published suggesting the model is valid. The sensitivity analysis was performed by sampling the input parameters from likely ranges and running the simulation many times rather than using single, best estimate values. This analysis shows that the magnitudes of the peak retractive forces on the lower teeth were highly sensitive to the chosen origin (and hence fibre direction) of the temporalis and masseter muscles as well as the laxity of the TMJ. Peak protrusive force was also sensitive to the masseter origin. These result shows that the model is insufficiently complex to estimate these values reliably although the much lower sensitivity values obtained for the bite forces in the other directions and also for the joint reaction forces suggest that these predictions are sound. Without the sensitivity analysis it would not have been possible to identify these weaknesses which strongly supports the use of sensitivity analysis as a validation technique for biomechanical modelling.

  17. Life beyond MSE and R2 — improving validation of predictive models with observations

    Science.gov (United States)

    Papritz, Andreas; Nussbaum, Madlene

    2017-04-01

    Machine learning and statistical predictive methods are evaluated by the closeness of predictions to observations of a test dataset. Common criteria for rating predictive methods are bias and mean square error (MSE), characterizing systematic and random prediction errors. Many studies also report R2-values, but their meaning is not always clear (correlation between observations and predictions or MSE skill score; Wilks, 2011). The same criteria are also used for choosing tuning parameters of predictive procedures by cross-validation and bagging (e.g. Hastie et al., 2009). For evident reasons, atmospheric sciences have developed a rich box of tools for forecast verification. Specific criteria have been proposed for evaluating deterministic and probabilistic predictions of binary, multinomial, ordinal and continuous responses (see reviews by Wilks, 2011, Jollie and Stephenson, 2012 and Gneiting et al., 2007). It appears that these techniques are not very well-known in the geosciences community interested in machine learning. In our presentation we review techniques that offer more insight into proximity of data and predictions than bias, MSE and R2 alone. We mention here only examples: (i) Graphing observations vs. predictions is usually more appropriate than the reverse (Piñeiro et al., 2008). (ii) The decomposition of the Brier score score (= MSE for probabilistic predictions of binary yes/no data) into reliability and resolution reveals (conditional) bias and capability of discriminating yes/no observations by the predictions. We illustrate the approaches by applications from digital soil mapping studies. Gneiting, T., Balabdaoui, F., and Raftery, A. E. (2007). Probabilistic forecasts, calibration and sharpness. Journal of the Royal Statistical Society Series B, 69, 243-268. Hastie, T., Tibshirani, R., and Friedman, J. (2009). The Elements of Statistical Learning; Data Mining, Inference and Prediction. Springer, New York, second edition. Jolliffe, I. T. and

  18. Publication bias and the failure of replication in experimental psychology.

    Science.gov (United States)

    Francis, Gregory

    2012-12-01

    Replication of empirical findings plays a fundamental role in science. Among experimental psychologists, successful replication enhances belief in a finding, while a failure to replicate is often interpreted to mean that one of the experiments is flawed. This view is wrong. Because experimental psychology uses statistics, empirical findings should appear with predictable probabilities. In a misguided effort to demonstrate successful replication of empirical findings and avoid failures to replicate, experimental psychologists sometimes report too many positive results. Rather than strengthen confidence in an effect, too much successful replication actually indicates publication bias, which invalidates entire sets of experimental findings. Researchers cannot judge the validity of a set of biased experiments because the experiment set may consist entirely of type I errors. This article shows how an investigation of the effect sizes from reported experiments can test for publication bias by looking for too much successful replication. Simulated experiments demonstrate that the publication bias test is able to discriminate biased experiment sets from unbiased experiment sets, but it is conservative about reporting bias. The test is then applied to several studies of prominent phenomena that highlight how publication bias contaminates some findings in experimental psychology. Additional simulated experiments demonstrate that using Bayesian methods of data analysis can reduce (and in some cases, eliminate) the occurrence of publication bias. Such methods should be part of a systematic process to remove publication bias from experimental psychology and reinstate the important role of replication as a final arbiter of scientific findings.

  19. Systematic review and retrospective validation of prediction models for weight loss after bariatric surgery.

    Science.gov (United States)

    Sharples, Alistair J; Mahawar, Kamal; Cheruvu, Chandra V N

    2017-08-12

    Patients often have less than realistic expectations of the weight loss they are likely to achieve after bariatric surgery. It would be useful to have a well-validated prediction tool that could give patients a realistic estimate of their expected weight loss. To perform a systematic review of the literature to identify existing prediction models and attempt to validate these models. University hospital, United Kingdom. A systematic review was performed. All English language studies were included if they used data to create a prediction model for postoperative weight loss after bariatric surgery. These models were then tested on patients undergoing bariatric surgery between January 1, 2013 and December 31, 2014 within our unit. An initial literature search produced 446 results, of which only 4 were included in the final review. Our study population included 317 patients. Mean preoperative body mass index was 46.1 ± 7.1. For 257 (81.1%) patients, 12-month follow-up was available, and mean body mass index and percentage excess weight loss at 12 months was 33.0 ± 6.7 and 66.1% ± 23.7%, respectively. All 4 of the prediction models significantly overestimated the amount of weight loss achieved by patients. The best performing prediction model in our series produced a correlation coefficient (R(2)) of .61 and an area under the curve of .71 on receiver operating curve analysis. All prediction models overestimated weight loss after bariatric surgery in our cohort. There is a need to develop better procedures and patient-specific models for better patient counselling. Copyright © 2017 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  20. Development and validation of a nomogram predicting recurrence risk in women with symptomatic urinary tract infection.

    Science.gov (United States)

    Cai, Tommaso; Mazzoli, Sandra; Migno, Serena; Malossini, Gianni; Lanzafame, Paolo; Mereu, Liliana; Tateo, Saverio; Wagenlehner, Florian M E; Pickard, Robert S; Bartoletti, Riccardo

    2014-09-01

    To develop and externally validate a novel nomogram predicting recurrence risk probability at 12 months in women after an episode of urinary tract infection. The study included 768 women from Santa Maria Annunziata Hospital, Florence, Italy, affected by urinary tract infections from January 2005 to December 2009. Another 373 women with the same criteria enrolled at Santa Chiara Hospital, Trento, Italy, from January 2010 to June 2012 were used to externally validate and calibrate the nomogram. Univariate and multivariate Cox regression models tested the relationship between urinary tract infection recurrence risk, and patient clinical and laboratory characteristics. The nomogram was evaluated by calculating concordance probabilities, as well as testing calibration of predicted urinary tract infection recurrence with observed urinary tract infections. Nomogram variables included: number of partners, bowel function, type of pathogens isolated (Gram-positive/negative), hormonal status, number of previous urinary tract infection recurrences and previous treatment of asymptomatic bacteriuria. Of the original development data, 261 out of 768 women presented at least one episode of recurrence of urinary tract infection (33.9%). The nomogram had a concordance index of 0.85. The nomogram predictions were well calibrated. This model showed high discrimination accuracy and favorable calibration characteristics. In the validation group (373 women), the overall c-index was 0.83 (P = 0.003, 95% confidence interval 0.51-0.99), whereas the area under the receiver operating characteristic curve was 0.85 (95% confidence interval 0.79-0.91). The present nomogram accurately predicts the recurrence risk of urinary tract infection at 12 months, and can assist in identifying women at high risk of symptomatic recurrence that can be suitable candidates for a prophylactic strategy. © 2014 The Japanese Urological Association.

  1. Remotely mapping river water quality using multivariate regression with prediction validation

    Science.gov (United States)

    Stork, Chris L.; Autrey, Bradley C.

    2005-09-01

    Remote spectral sensing offers an attractive means of mapping river water quality over wide spatial regions. While previous research has focused on development of spectral indices and models to predict river water quality based on remote images, little attention has been paid to subsequent validation of these predictions. To address this oversight, we describe a retrospective analysis of remote, multispectral Compact Airborne Spectrographic Imager (CASI) images of the Ohio River and its Licking River and Little Miami River tributaries. In conjunction with the CASI acquisitions, ground truth measurements of chlorophyll-a concentration and turbidity were made for a small set of locations in the Ohio River. Partial least squares regression models relating the remote river images to ground truth measurements of chlorophyll-a concentration and turbidity for the Ohio River were developed. Employing these multivariate models, chlorophyll-a concentrations and turbidity levels were predicted in river pixels lacking ground truth measurements, generating detailed estimated water quality maps. An important but often neglected step in the regression process is to validate prediction results using a spectral residual statistic. For both the chlorophyll-a and turbidity regression models, a spectral residual value was calculated for each river pixel and compared to the associated statistical confidence limit for the model. These spectral residual statistic results revealed that while the chlorophyll-a and turbidity models could validly be applied to a vast majority of Ohio River and Licking River pixels, application of these models to Little Miami River pixels was inappropriate due to an unmodeled source of spectral variation.

  2. Prediction Models and Their External Validation Studies for Mortality of Patients with Acute Kidney Injury: A Systematic Review

    Science.gov (United States)

    Ohnuma, Tetsu; Uchino, Shigehiko

    2017-01-01

    Objectives To systematically review AKI outcome prediction models and their external validation studies, to describe the discrepancy of reported accuracy between the results of internal and external validations, and to identify variables frequently included in the prediction models. Methods We searched the MEDLINE and Web of Science electronic databases (until January 2016). Studies were eligible if they derived a model to predict mortality of AKI patients or externally validated at least one of the prediction models, and presented area under the receiver-operator characteristic curves (AUROC) to assess model discrimination. Studies were excluded if they described only results of logistic regression without reporting a scoring system, or if a prediction model was generated from a specific cohort. Results A total of 2204 potentially relevant articles were found and screened, of which 12 articles reporting original prediction models for hospital mortality in AKI patients and nine articles assessing external validation were selected. Among the 21 studies for AKI prediction models and their external validation, 12 were single-center (57%), and only three included more than 1,000 patients (14%). The definition of AKI was not uniform and none used recently published consensus criteria for AKI. Although good performance was reported in their internal validation, most of the prediction models had poor discrimination with an AUROC below 0.7 in the external validation studies. There were 10 common non-renal variables that were reported in more than three prediction models: mechanical ventilation, age, gender, hypotension, liver failure, oliguria, sepsis/septic shock, low albumin, consciousness and low platelet count. Conclusions Information in this systematic review should be useful for future prediction model derivation by providing potential candidate predictors, and for future external validation by listing up the published prediction models. PMID:28056039

  3. An approach to model validation and model-based prediction -- polyurethane foam case study.

    Energy Technology Data Exchange (ETDEWEB)

    Dowding, Kevin J.; Rutherford, Brian Milne

    2003-07-01

    Enhanced software methodology and improved computing hardware have advanced the state of simulation technology to a point where large physics-based codes can be a major contributor in many systems analyses. This shift toward the use of computational methods has brought with it new research challenges in a number of areas including characterization of uncertainty, model validation, and the analysis of computer output. It is these challenges that have motivated the work described in this report. Approaches to and methods for model validation and (model-based) prediction have been developed recently in the engineering, mathematics and statistical literatures. In this report we have provided a fairly detailed account of one approach to model validation and prediction applied to an analysis investigating thermal decomposition of polyurethane foam. A model simulates the evolution of the foam in a high temperature environment as it transforms from a solid to a gas phase. The available modeling and experimental results serve as data for a case study focusing our model validation and prediction developmental efforts on this specific thermal application. We discuss several elements of the ''philosophy'' behind the validation and prediction approach: (1) We view the validation process as an activity applying to the use of a specific computational model for a specific application. We do acknowledge, however, that an important part of the overall development of a computational simulation initiative is the feedback provided to model developers and analysts associated with the application. (2) We utilize information obtained for the calibration of model parameters to estimate the parameters and quantify uncertainty in the estimates. We rely, however, on validation data (or data from similar analyses) to measure the variability that contributes to the uncertainty in predictions for specific systems or units (unit-to-unit variability). (3) We perform statistical

  4. Development and validation of prediction models for blood concentrations of dioxins and PCBs using dietary intakes.

    Science.gov (United States)

    Kvalem, Helen Engelstad; Brantsæter, Anne Lise; Meltzer, Helle Margrete; Stigum, Hein; Thomsen, Cathrine; Haugen, Margaretha; Alexander, Jan; Knutsen, Helle K

    2012-12-01

    Dioxins and PCBs accumulate in the food chain and might exert toxic effects in animals and humans. In large epidemiologic studies, exposure estimates of these compounds based on analyses of biological material might not be available or affordable. To develop and then validate models for predicting concentrations of dioxins and PCBs in blood using a comprehensive food frequency questionnaire and blood concentrations. Prediction models were built on data from one study (n=195), and validated in an independent study group (n=66). We used linear regression to develop predictive models for dioxins and PCBs, both sums of congeners and 33 single congeners (7 and 10 polychlorinated dibenzo-p-dioxins and furans (PCDDs/PCDFs), 12 dioxin-like polychlorinated biphenyls (PCBs: 4 non-ortho and 8 mono-ortho), sum of all the 29 dioxin-like compounds (total TEQ) and sum of 4 non dioxin-like PCBs (∑ CB-101, 138, 153, 183=PCB(4)). We used the blood concentration and dietary intake of each of the above as dependent and independent variables, while sex, parity, age, place of living, smoking status, energy intake and education were covariates. We validated the models in a new study population comparing the predicted blood concentrations with the measured blood concentrations using correlation coefficients and Weighted Kappa (К(W)) as measures of agreement, considering К(W)>0.40 as successful prediction. The models explained 78% (sum dioxin-like compounds), 76% (PCDDs), 76% (PCDFs), 74% (no-PCBs), 69% (mo-PCBs), 68% (PCB(4)) and 63% (CB-153) of the variance. In addition to dietary intake, age and sex were the most important covariates. The predicted blood concentrations were highly correlated with the measured values, with r=0.75 for dl-compounds 0.70 for PCB(4), (p0.40. The models developed had high power to predict blood levels of dioxins and PCBs and to correctly rank subjects according to high or low exposure based on dietary intake and demographic information. These models

  5. The validated embryonic stem cell test to predict embryotoxicity in vitro.

    Science.gov (United States)

    Seiler, Andrea E M; Spielmann, Horst

    2011-06-16

    In the embryonic stem cell test (EST), differentiation of mouse embryonic stem cells (mESCs) is used as a model to assess embryotoxicity in vitro. The test was successfully validated by the European Center for the Validation of Alternative Methods (ECVAM) and models fundamental mechanisms in embryotoxicity, such as cytotoxicity and differentiation. In addition, differences in sensitivity between differentiated (adult) and embryonic cells are also taken into consideration. To predict the embryotoxic potential of a test substance, three endpoints are assessed: the inhibition of differentiation into beating cardiomyocytes, the cytotoxic effects on stem cells and the cytotoxic effects on 3T3 fibroblasts. A special feature of the EST is that it is solely based on permanent cell lines so that primary embryonic cells and tissues from pregnant animals are not needed. In this protocol, we describe the ECVAM-validated method, in which the morphological assessment of contracting cardiomyocytes is used as an endpoint for differentiation, and the molecular-based FACS-EST method, in which highly predictive protein markers specific for developing heart tissue were selected. With these methods, the embryotoxic potency of a compound can be assessed in vitro within 10 or 7 d, respectively.

  6. A Replication of the Autism Diagnostic Observation Schedule (ADOS) Revised Algorithms

    Science.gov (United States)

    Gotham, Katherine; Risi, Susan; Dawson, Geraldine; Tager-Flusberg, Helen; Joseph, Robert; Carter, Alice; Hepburn, Susan; McMahon, William; Rodier, Patricia; Hyman, Susan L.; Sigman, Marian; Rogers, Sally; Landa, Rebecca; Spence, M. Anne; Osann, Kathryn; Flodman, Pamela; Volkmar, Fred; Hollander, Eric; Buxbaum, Joseph; Pickles, Andrew; Lord, Catherine

    2008-01-01

    A study replicated the module comparability and predictive ability of the revised algorithms of the Autism Diagnostic Observation Schedule (ADOS) in an independent dataset of children with autism. Results indicated that the revised ADOS algorithms improved module comparability and predictive validity for autistic children than the earlier…

  7. A Replication of the Autism Diagnostic Observation Schedule (ADOS) Revised Algorithms

    Science.gov (United States)

    Gotham, Katherine; Risi, Susan; Dawson, Geraldine; Tager-Flusberg, Helen; Joseph, Robert; Carter, Alice; Hepburn, Susan; McMahon, William; Rodier, Patricia; Hyman, Susan L.; Sigman, Marian; Rogers, Sally; Landa, Rebecca; Spence, M. Anne; Osann, Kathryn; Flodman, Pamela; Volkmar, Fred; Hollander, Eric; Buxbaum, Joseph; Pickles, Andrew; Lord, Catherine

    2008-01-01

    A study replicated the module comparability and predictive ability of the revised algorithms of the Autism Diagnostic Observation Schedule (ADOS) in an independent dataset of children with autism. Results indicated that the revised ADOS algorithms improved module comparability and predictive validity for autistic children than the earlier…

  8. Prediction models for intracranial hemorrhage or major bleeding in patients on antiplatelet therapy : a systematic review and external validation study

    NARCIS (Netherlands)

    Hilkens, NA; Algra, A|info:eu-repo/dai/nl/07483472X; Greving, JP|info:eu-repo/dai/nl/298701278

    2016-01-01

    ESSENTIALS: Prediction models may help to identify patients at high risk of bleeding on antiplatelet therapy. We identified existing prediction models for bleeding and validated them in patients with cerebral ischemia. Five prediction models were identified, all of which had some methodological shor

  9. Validation that Metabolic Tumor Volume Predicts Outcome in Head-and-Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chad; Murphy, James D.; Khong, Brian; La, Trang H. [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Kong, Christina [Department of Pathology, Stanford University, Stanford, CA (United States); Fischbein, Nancy J. [Department of Radiology, Stanford University, Stanford, CA (United States); Colevas, A. Dimitrios [Division of Medical Oncology, Department of Medicine, Stanford University, Stanford, CA (United States); Iagaru, Andrei H. [Department of Radiology, Stanford University, Stanford, CA (United States); Graves, Edward E.; Loo, Billy W. [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Le, Quynh-Thu, E-mail: qle@stanford.edu [Department of Radiation Oncology, Stanford University, Stanford, CA (United States)

    2012-08-01

    Purpose: We have previously reported that metabolic tumor volume (MTV) obtained from pretreatment {sup 18}F-fluorodeoxydeglucose positron emission tomography (FDG PET)/ computed tomography (CT) predicted outcome in patients with head-and-neck cancer (HNC). The purpose of this study was to validate these results on an independent dataset, determine whether the primary tumor or nodal MTV drives this correlation, and explore the interaction with p16{sup INK4a} status as a surrogate marker for human papillomavirus (HPV). Methods and Materials: The validation dataset in this study included 83 patients with squamous cell HNC who had a FDG PET/CT scan before receiving definitive radiotherapy. MTV and maximum standardized uptake value (SUV{sub max}) were calculated for the primary tumor, the involved nodes, and the combination of both. The primary endpoint was to validate that MTV predicted progression-free survival and overall survival. Secondary analyses included determining the prognostic utility of primary tumor vs. nodal MTV. Results: Similarly to our prior findings, an increase in total MTV of 17 cm{sup 3} (difference between the 75th and 25th percentiles) was associated with a 2.1-fold increase in the risk of disease progression (p = 0.0002) and a 2.0-fold increase in the risk of death (p = 0.0048). SUV{sub max} was not associated with either outcome. Primary tumor MTV predicted progression-free (hazard ratio [HR] = 1.94; p < 0.0001) and overall (HR = 1.57; p < 0.0001) survival, whereas nodal MTV did not. In addition, MTV predicted progression-free (HR = 4.23; p < 0.0001) and overall (HR = 3.21; p = 0.0029) survival in patients with p16{sup INK4a}-positive oropharyngeal cancer. Conclusions: This study validates our previous findings that MTV independently predicts outcomes in HNC. MTV should be considered as a potential risk-stratifying biomarker in future studies of HNC.

  10. Predicting high-cost pediatric patients: derivation and validation of a population-based model.

    Science.gov (United States)

    Leininger, Lindsey J; Saloner, Brendan; Wherry, Laura R

    2015-08-01

    Health care administrators often lack feasible methods to prospectively identify new pediatric patients with high health care needs, precluding the ability to proactively target appropriate population health management programs to these children. To develop and validate a predictive model identifying high-cost pediatric patients using parent-reported health (PRH) measures that can be easily collected in clinical and administrative settings. Retrospective cohort study using 2-year panel data from the 2001 to 2011 rounds of the Medical Expenditure Panel Survey. A total of 24,163 children aged 5-17 with family incomes below 400% of the federal poverty line were included in this study. Predictive performance, including the c-statistic, sensitivity, specificity, and predictive values, of multivariate logistic regression models predicting top-decile health care expenditures over a 1-year period. Seven independent domains of PRH measures were tested for predictive capacity relative to basic sociodemographic information: the Children with Special Health Care Needs (CSHCN) Screener; subjectively rated health status; prior year health care utilization; behavioral problems; asthma diagnosis; access to health care; and parental health status and access to care. The CSHCN screener and prior year utilization domains exhibited the highest incremental predictive gains over the baseline model. A model including sociodemographic characteristics, the CSHCN screener, and prior year utilization had a c-statistic of 0.73 (95% confidence interval, 0.70-0.74), surpassing the commonly used threshold to establish sufficient predictive capacity (c-statistic>0.70). The proposed prediction tool, comprising a simple series of PRH measures, accurately stratifies pediatric populations by their risk of incurring high health care costs.

  11. Validating a model that predicts daily growth and feed quality of New Zealand dairy pastures.

    Science.gov (United States)

    Woodward, S J

    2001-09-01

    The Pasture Quality (PQ) model is a simple, mechanistic, dynamical system model that was designed to capture the essential biological processes in grazed grass-clover pasture, and to be optimised to derive improved grazing strategies for New Zealand dairy farms. While the individual processes represented in the model (photosynthesis, tissue growth, flowering, leaf death, decomposition, worms) were based on experimental data, this did not guarantee that the assembled model would accurately predict the behaviour of the system as a whole (i.e., pasture growth and quality). Validation of the whole model was thus a priority, since any strategy derived from the model could impact a farm business in the order of thousands of dollars per annum if adopted. This paper describes the process of defining performance criteria for the model, obtaining suitable data to test the model, and carrying out the validation analysis. The validation process highlighted a number of weaknesses in the model, which will lead to the model being improved. As a result, the model's utility will be enhanced. Furthermore, validation was found to have an unexpected additional benefit, in that despite the model's poor initial performance, support was generated for the model among field scientists involved in the wider project.

  12. Analytical prediction and field validation of transient temperature field in asphalt pavements

    Institute of Scientific and Technical Information of China (English)

    陈嘉祺; 李亮; 汪浩

    2015-01-01

    This work presented the development and validation of an analytical method to predict the transient temperature field in the asphalt pavement. The governing equation for heat transfer was based on heat conduction radiation and convection. An innovative time-dependent function was proposed to predict the pavement surface temperature with solar radiation and air temperature using dimensional analysis in order to simplify the complex heat exchange on the pavement surface. The parameters for the time-dependent pavement surface temperature function were obtained through the regression analysis of field measurement data. Assuming that the initial pavement temperature distribution was linear and the influence of the base course materials on the temperature of the upper asphalt layers was negligible, a close-form analytical solution of the temperature in asphalt layers was derived using Green’s function. Finally, two numerical examples were presented to validate the model solutions with field temperature measurements. Analysis results show that the solution accuracy is in agreement with field data and the relative errors at a shallower depth are greater than those at a deeper one. Although the model is not sensitive to dramatic changes in climatic factors near the pavement surface, it is applicable for predicting pavement temperature field in cloudless days.

  13. Predictive validity of the Sødring Motor Evaluation of Stroke Patients (SMES).

    Science.gov (United States)

    Wyller, T B; Sødring, K M; Sveen, U; Ljunggren, A E; Bautz-Holter, E

    1996-12-01

    The Sødring Motor Evaluation of Stroke Patients (SMES) has been developed as an instrument for the evaluation by physiotherapists of motor function and activities in stroke patients. The predictive validity of the instrument was studied in a consecutive sample of 93 acute stroke patients, assessed in the acute phase and after one year. The outcome measures were: survival, residence at home or in institution, the Barthel ADL index (dichotomized at 19/20), and the Frenchay Activities Index (FAI) (dichotomized at 9/10). The SMES, scored in the acute phase, demonstrated a marginally significant predictive power regarding survival, but was a highly significant predictor regarding the other outcomes. The adjusted odds ratio for a good versus a poor outcome for patients in the upper versus the lower tertile of the SMES arm subscore was 5.4 (95% confidence interval 0.9-59) for survival, 11.5 (2.1-88) for living at home, 86.3 (11-infinity) for a high Barthel score, and 31.4 (5.2-288) for a high FAI score. We conclude that SMES has high predictive validity.

  14. Predicting NCLEX-RN success with the HESI Exit Exam: eighth validity study.

    Science.gov (United States)

    Langford, Rae; Young, Anne

    2013-01-01

    Increasingly, Elsevier's HESI Exit Exam (E(2)) is being used to assess students' readiness for the National Council Licensure Examination for Registered Nurses (NCLEX-RN). Seven previously conducted validity studies indicate that the E(2) is 96.36%-99.16% accurate in predicting NCLEX-RN success. Findings of this eighth validity study, which also investigated the predictive accuracy of repeat testing with parallel versions of the E(2), indicated that the E(2) is highly accurate (94.93%-98.32%) in predicting NCLEX-RN success for the initial testing and 2 retests. Of the 66 participating nursing programs, deans and directors from 43 (65.15%) of the programs reported implementing a policy that used E(2) scores as a benchmark for remediation. A score of 850 was the most common E(2) benchmark designated by faculties, and students who failed to achieve the faculty-designated E(2) benchmark score were required to retest with a parallel version of the E(2). Remediation resources used to assist students in achieving faculty-designated E(2) benchmark scores varied widely, with many programs employing multiple remediation methods.

  15. Scoring System Development and Validation for Prediction Choledocholithiasis before Open Cholecystectomy.

    Science.gov (United States)

    Pejović, Tomislav; Stojadinović, Miroslav M

    2015-01-01

    Accurate precholecystectomy detection of concurrent asymptomatic common bile duct stones (CBDS) is key in the clinical decision-making process. The standard preoperative methods used to diagnose these patients are often not accurate enough. The aim of the study was to develop a scoring model that would predict CBDS before open cholecystectomy. We retrospectively collected preoperative (demographic, biochemical, ultrasonographic) and intraoperative (intraoperative cholangiography) data for 313 patients at the department of General Surgery at Gornji Milanovac from 2004 to 2007. The patients were divided into a derivation (213) and a validation set (100). Univariate and multivariate regression analysis was used to determine independent predictors of CBDS. These predictors were used to develop scoring model. Various measures for the assessment of risk prediction models were determined, such as predictive ability, accuracy, the area under the receiver operating characteristic curve (AUC), calibration and clinical utility using decision curve analysis. In a univariate analysis, seven risk factors displayed significant correlation with CBDS. Total bilirubin, alkaline phosphatase and bile duct dilation were identified as independent predictors of choledocholithiasis. The resultant total possible score in the derivation set ranged from 7.6 to 27.9. Scoring model shows good discriminatory ability in the derivation and validation set (AUC 94.3 and 89.9%, respectively), excellent accuracy (95.5%), satisfactory calibration in the derivation set, similar Brier scores and clinical utility in decision curve analysis. Developed scoring model might successfully estimate the presence of choledocholithiasis in patients planned for elective open cholecystectomy.

  16. The cancer information overload (CIO) scale: establishing predictive and discriminant validity.

    Science.gov (United States)

    Jensen, Jakob D; Carcioppolo, Nick; King, Andy J; Scherr, Courtney L; Jones, Christina L; Niederdieppe, Jeff

    2014-01-01

    Survey data suggests that approximately three-fourths of adults are overwhelmed by cancer information - a construct we label cancer information overload (CIO). A significant limitation of existing research is that it relies on a single-item measure. The objective of the current study is to develop and validate a multi-item measure of CIO. Study 1 (N=209) surveyed healthcare and manufacturing employees at eight worksites. Colonoscopy insurance claims data were culled eighteen months later to evaluate the predictive validity of CIO. Study 2 (N=399) surveyed adults at seven shopping malls. CIO and cancer fatalism were measured to examine the properties of the two constructs. Study 1 identified a reliable 8-item CIO scale that significantly predicted colonoscopy insurance claims 18 months after the initial survey. Study 2 confirmed the factor structure identified in Study 1, and demonstrated that CIO, cancer fatalism about prevention, and cancer fatalism about treatment are best modeled as three distinct constructs. The perception that there are too many recommendations about cancer prevention to know which ones to follow is an indicator of CIO, a widespread disposition that predicts colon cancer screening and is related to, but distinct from, cancer fatalism. Many adults exhibit high CIO, a disposition that undermines health efforts. Communication strategies that mitigate CIO are a priority. In the short-term, health care providers and public health professionals should monitor the amount of information provided to patients and the public. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Prediction and Validation of Promoters Involved in the Abscisic Acid Response in Physcomitrella patens

    Institute of Scientific and Technical Information of China (English)

    Gerrit Timmerhaus; Sebastian T.Hanke; Karl Buchta; Stefan A. Rensing

    2011-01-01

    Detection of cis-regulatory elements, such as transcription factor binding sites (TFBS), through utilization of ortholog conservation is possible only if genomic data from closely related organisms are available. An alternative ap-proach is the detection of TFBS based on their overrepresentation in promoters of co-regulated genes. However, this ap-proach usually suffers from a high rate of false-positive prediction. Here, we have conducted a case study using promoters of genes known to be strongly induced by the phytohormone abscisic acid (ABA)in the model plant Physcornitrella patens,a moss. Putative TFBS were detected using three de novo motif detection tools in a strict consensus approach. The resulting motifs were validated using data from microarray expression profiling and were able to predict ABA-induced genes with high specificity (90.48%)at mediocre sensitivity (33.33%). In addition, 27 genes predicted to contain ABA-responsive TFBS were validated using real-time PCR. Here, a total of 37% of the genes could be shown to be induced upon ABA treatment,while 70% were found to be regulated by ABA. We conclude that the consensus approach for motif detection using co-regulation information can be used to identify genes that are regulated under a given stimulus. In terms of evolution, we find that the ABA response has apparently been conserved since the first land plants on the level of families involved in transcriptional regulation.

  18. A predictive bone drilling force model for haptic rendering with experimental validation using fresh cadaveric bone.

    Science.gov (United States)

    Lin, Yanping; Chen, Huajiang; Yu, Dedong; Zhang, Ying; Yuan, Wen

    2017-01-01

    Bone drilling simulators with virtual and haptic feedback provide a safe, cost-effective and repeatable alternative to traditional surgical training methods. To develop such a simulator, accurate haptic rendering based on a force model is required to feedback bone drilling forces based on user input. Current predictive bone drilling force models based on bovine bones with various drilling conditions and parameters are not representative of the bone drilling process in bone surgery. The objective of this study was to provide a bone drilling force model for haptic rendering based on calibration and validation experiments in fresh cadaveric bones with different bone densities. Using a commonly used drill bit geometry (2 mm diameter), feed rates (20-60 mm/min) and spindle speeds (4000-6000 rpm) in orthognathic surgeries, the bone drilling forces of specimens from two groups were measured and the calibration coefficients of the specific normal and frictional pressures were determined. The comparison of the predicted forces and the measured forces from validation experiments with a large range of feed rates and spindle speeds demonstrates that the proposed bone drilling forces can predict the trends and average forces well. The presented bone drilling force model can be used for haptic rendering in surgical simulators.

  19. Estimating the predictive validity of diabetic animal models in rosiglitazone studies.

    Science.gov (United States)

    Varga, O E; Zsíros, N; Olsson, I A S

    2015-06-01

    For therapeutic studies, predictive validity of animal models - arguably the most important feature of animal models in terms of human relevance - can be calculated retrospectively by obtaining data on treatment efficacy from human and animal trials. Using rosiglitazone as a case study, we aim to determine the predictive validity of animal models of diabetes, by analysing which models perform most similarly to humans during rosiglitazone treatment in terms of changes in standard diabetes diagnosis parameters (glycosylated haemoglobin [HbA1c] and fasting glucose levels). A further objective of this paper was to explore the impact of four covariates on the predictive capacity: (i) diabetes induction method; (ii) drug administration route; (iii) sex of animals and (iv) diet during the experiments. Despite the variable consistency of animal species-based models with the human reference for glucose and HbA1c treatment effects, our results show that glucose and HbA1c treatment effects in rats agreed better with the expected values based on human data than in other species. Induction method was also found to be a substantial factor affecting animal model performance. The study concluded that regular reassessment of animal models can help to identify human relevance of each model and adapt research design for actual research goals.

  20. Prediction of the thermal decomposition of organic peroxides by validated QSPR models.

    Science.gov (United States)

    Prana, Vinca; Rotureau, Patricia; Fayet, Guillaume; André, David; Hub, Serge; Vicot, Patricia; Rao, Li; Adamo, Carlo

    2014-07-15

    Organic peroxides are unstable chemicals which can easily decompose and may lead to explosion. Such a process can be characterized by physico-chemical parameters such as heat and temperature of decomposition, whose determination is crucial to manage related hazards. These thermal stability properties are also required within many regulatory frameworks related to chemicals in order to assess their hazardous properties. In this work, new quantitative structure-property relationships (QSPR) models were developed to predict accurately the thermal stability of organic peroxides from their molecular structure respecting the OECD guidelines for regulatory acceptability of QSPRs. Based on the acquisition of 38 reference experimental data using DSC (differential scanning calorimetry) apparatus in homogenous experimental conditions, multi-linear models were derived for the prediction of the decomposition heat and the onset temperature using different types of molecular descriptors. Models were tested by internal and external validation tests and their applicability domains were defined and analyzed. Being rigorously validated, they presented the best performances in terms of fitting, robustness and predictive power and the descriptors used in these models were linked to the peroxide bond whose breaking represents the main decomposition mechanism of organic peroxides.

  1. Development and Validation of Predictive Indices for a Continuous Outcome Using Gene Expression Profiles

    Directory of Open Access Journals (Sweden)

    Yingdong Zhao

    2010-05-01

    Full Text Available There have been relatively few publications using linear regression models to predict a continuous response based on microarray expression profiles. Standard linear regression methods are problematic when the number of predictor variables exceeds the number of cases. We have evaluated three linear regression algorithms that can be used for the prediction of a continuous response based on high dimensional gene expression data. The three algorithms are the least angle regression (LAR, the least absolute shrinkage and selection operator (LASSO, and the averaged linear regression method (ALM. All methods are tested using simulations based on a real gene expression dataset and analyses of two sets of real gene expression data and using an unbiased complete cross validation approach. Our results show that the LASSO algorithm often provides a model with somewhat lower prediction error than the LAR method, but both of them perform more efficiently than the ALM predictor. We have developed a plug-in for BRB-ArrayTools that implements the LAR and the LASSO algorithms with complete cross-validation.

  2. An Experimental Simulation to Validate FEM to Predict Transverse Young’s Modulus of FRP Composites

    Directory of Open Access Journals (Sweden)

    V. S. Sai

    2013-01-01

    Full Text Available Finite element method finds application in the analysis of FRP composites due to its versatility in getting the solution for complex cases which are not possible by exact classical analytical approaches. The finite element result is questionable unless it is obtained from converged mesh and properly validated. In the present work specimens are prepared with metallic materials so that the arrangement of fibers is close to hexagonal packing in a matrix as similar arrangement in case of FRP is complex due to the size of fibers. Transverse Young’s moduli of these specimens are determined experimentally. Equivalent FE models are designed and corresponding transverse Young’s moduli are compared with the experimental results. It is observed that the FE values are in good agreement with the experimental results, thus validating FEM for predicting transverse modulus of FRP composites.

  3. Predictive validity of the ASAM Patient Placement Criteria for hospital utilization.

    Science.gov (United States)

    Sharon, Estee; Krebs, Chris; Turner, Winston; Desai, Nitigna; Binus, Gregory; Penk, Walter; Gastfriend, David R

    2003-01-01

    We tested the validity of the ASAM Patient Placement Criteria (PPC) using the first complete and reliable computerized implementation of these criteria. Adult U.S. veterans (N = 95) seeking substance abuse treatment were blindly assessed for level of care need according to the PPC but were naturalistically assigned by counselors to residential rehabilitation (Level III) without knowledge of the PPC recommendation. Analyses compared subjects across three levels of recommended care, based on the algorithm, for utilization outcomes of VA hospital admissions and bed days of care. Subjects who were mismatched to lesser level of care than recommended utilized nearly twice as many hospital bed-days over the subsequent year (F (2;92) = 3.88; p ASAM Criteria. A comprehensive implementation is an important methodologic requirement. These preliminary results support predictive validity for the ASAM Criteria, in that mismatching may be associated with excessive hospital utilization.

  4. Validity of Treadmill-Derived Critical Speed on Predicting 5000-Meter Track-Running Performance.

    Science.gov (United States)

    Nimmerichter, Alfred; Novak, Nina; Triska, Christoph; Prinz, Bernhard; Breese, Brynmor C

    2017-03-01

    Nimmerichter, A, Novak, N, Triska, C, Prinz, B, and Breese, BC. Validity of treadmill-derived critical speed on predicting 5,000-meter track-running performance. J Strength Cond Res 31(3): 706-714, 2017-To evaluate 3 models of critical speed (CS) for the prediction of 5,000-m running performance, 16 trained athletes completed an incremental test on a treadmill to determine maximal aerobic speed (MAS) and 3 randomly ordered runs to exhaustion at the [INCREMENT]70% intensity, at 110% and 98% of MAS. Critical speed and the distance covered above CS (D') were calculated using the hyperbolic speed-time (HYP), the linear distance-time (LIN), and the linear speed inverse-time model (INV). Five thousand meter performance was determined on a 400-m running track. Individual predictions of 5,000-m running time (t = [5,000-D']/CS) and speed (s = D'/t + CS) were calculated across the 3 models in addition to multiple regression analyses. Prediction accuracy was assessed with the standard error of estimate (SEE) from linear regression analysis and the mean difference expressed in units of measurement and coefficient of variation (%). Five thousand meter running performance (speed: 4.29 ± 0.39 m·s; time: 1,176 ± 117 seconds) was significantly better than the predictions from all 3 models (p distances of 5,000 m.

  5. Comparison and validation of statistical methods for predicting power outage durations in the event of hurricanes.

    Science.gov (United States)

    Nateghi, Roshanak; Guikema, Seth D; Quiring, Steven M

    2011-12-01

    This article compares statistical methods for modeling power outage durations during hurricanes and examines the predictive accuracy of these methods. Being able to make accurate predictions of power outage durations is valuable because the information can be used by utility companies to plan their restoration efforts more efficiently. This information can also help inform customers and public agencies of the expected outage times, enabling better collective response planning, and coordination of restoration efforts for other critical infrastructures that depend on electricity. In the long run, outage duration estimates for future storm scenarios may help utilities and public agencies better allocate risk management resources to balance the disruption from hurricanes with the cost of hardening power systems. We compare the out-of-sample predictive accuracy of five distinct statistical models for estimating power outage duration times caused by Hurricane Ivan in 2004. The methods compared include both regression models (accelerated failure time (AFT) and Cox proportional hazard models (Cox PH)) and data mining techniques (regression trees, Bayesian additive regression trees (BART), and multivariate additive regression splines). We then validate our models against two other hurricanes. Our results indicate that BART yields the best prediction accuracy and that it is possible to predict outage durations with reasonable accuracy. © 2011 Society for Risk Analysis.

  6. Validation of a multifactorial risk factor model used for predicting future caries risk with nevada adolescents

    Directory of Open Access Journals (Sweden)

    Mobley Connie

    2011-05-01

    Full Text Available Abstract Background The objective of this study was to measure the validity and reliability of a multifactorial Risk Factor Model developed for use in predicting future caries risk in Nevada adolescents in a public health setting. Methods This study examined retrospective data from an oral health surveillance initiative that screened over 51,000 students 13-18 years of age, attending public/private schools in Nevada across six academic years (2002/2003-2007/2008. The Risk Factor Model included ten demographic variables: exposure to fluoridation in the municipal water supply, environmental smoke exposure, race, age, locale (metropolitan vs. rural, tobacco use, Body Mass Index, insurance status, sex, and sealant application. Multiple regression was used in a previous study to establish which significantly contributed to caries risk. Follow-up logistic regression ascertained the weight of contribution and odds ratios of the ten variables. Researchers in this study computed sensitivity, specificity, positive predictive value (PVP, negative predictive value (PVN, and prevalence across all six years of screening to assess the validity of the Risk Factor Model. Results Subjects' overall mean caries prevalence across all six years was 66%. Average sensitivity across all six years was 79%; average specificity was 81%; average PVP was 89% and average PVN was 67%. Conclusions Overall, the Risk Factor Model provided a relatively constant, valid measure of caries that could be used in conjunction with a comprehensive risk assessment in population-based screenings by school nurses/nurse practitioners, health educators, and physicians to guide them in assessing potential future caries risk for use in prevention and referral practices.

  7. Development and validation of a seizure prediction model in critically ill children.

    Science.gov (United States)

    Yang, Amy; Arndt, Daniel H; Berg, Robert A; Carpenter, Jessica L; Chapman, Kevin E; Dlugos, Dennis J; Gallentine, William B; Giza, Christopher C; Goldstein, Joshua L; Hahn, Cecil D; Lerner, Jason T; Loddenkemper, Tobias; Matsumoto, Joyce H; Nash, Kendall B; Payne, Eric T; Sánchez Fernández, Iván; Shults, Justine; Topjian, Alexis A; Williams, Korwyn; Wusthoff, Courtney J; Abend, Nicholas S

    2015-02-01

    Electrographic seizures are common in encephalopathic critically ill children, but identification requires continuous EEG monitoring (CEEG). Development of a seizure prediction model would enable more efficient use of limited CEEG resources. We aimed to develop and validate a seizure prediction model for use among encephalopathic critically ill children. We developed a seizure prediction model using a retrospectively acquired multi-center database of children with acute encephalopathy without an epilepsy diagnosis, who underwent clinically indicated CEEG. We performed model validation using a separate prospectively acquired single center database. Predictor variables were chosen to be readily available to clinicians prior to the onset of CEEG and included: age, etiology category, clinical seizures prior to CEEG, initial EEG background category, and inter-ictal discharge category. The model has fair to good discrimination ability and overall performance. At the optimal cut-off point in the validation dataset, the model has a sensitivity of 59% and a specificity of 81%. Varied cut-off points could be chosen to optimize sensitivity or specificity depending on available CEEG resources. Despite inherent variability between centers, a model developed using multi-center CEEG data and few readily available variables could guide the use of limited CEEG resources when applied at a single center. Depending on CEEG resources, centers could choose lower cut-off points to maximize identification of all patients with seizures (but with more patients monitored) or higher cut-off points to reduce resource utilization by reducing monitoring of lower risk patients (but with failure to identify some patients with seizures). Copyright © 2014 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  8. Discovery and validation of a prostate cancer genomic classifier that predicts early metastasis following radical prostatectomy.

    Directory of Open Access Journals (Sweden)

    Nicholas Erho

    Full Text Available PURPOSE: Clinicopathologic features and biochemical recurrence are sensitive, but not specific, predictors of metastatic disease and lethal prostate cancer. We hypothesize that a genomic expression signature detected in the primary tumor represents true biological potential of aggressive disease and provides improved prediction of early prostate cancer metastasis. METHODS: A nested case-control design was used to select 639 patients from the Mayo Clinic tumor registry who underwent radical prostatectomy between 1987 and 2001. A genomic classifier (GC was developed by modeling differential RNA expression using 1.4 million feature high-density expression arrays of men enriched for rising PSA after prostatectomy, including 213 who experienced early clinical metastasis after biochemical recurrence. A training set was used to develop a random forest classifier of 22 markers to predict for cases--men with early clinical metastasis after rising PSA. Performance of GC was compared to prognostic factors such as Gleason score and previous gene expression signatures in a withheld validation set. RESULTS: Expression profiles were generated from 545 unique patient samples, with median follow-up of 16.9 years. GC achieved an area under the receiver operating characteristic curve of 0.75 (0.67-0.83 in validation, outperforming clinical variables and gene signatures. GC was the only significant prognostic factor in multivariable analyses. Within Gleason score groups, cases with high GC scores experienced earlier death from prostate cancer and reduced overall survival. The markers in the classifier were found to be associated with a number of key biological processes in prostate cancer metastatic disease progression. CONCLUSION: A genomic classifier was developed and validated in a large patient cohort enriched with prostate cancer metastasis patients and a rising PSA that went on to experience metastatic disease. This early metastasis prediction model based on

  9. The diagnostic validity of clinical airway assessments for predicting difficult laryngoscopy using a grey zone approach.

    Science.gov (United States)

    Min, Jeong Jin; Kim, Gahyun; Kim, Eunhee; Lee, Jong-Hwan

    2016-08-01

    The diagnostic validity of clinical airway assessment tests for predicting difficult laryngoscopy in patients requiring endotracheal intubation were evaluated using receiver operating characteristic (ROC) curve analysis and a grey zone approach. In this prospective observational study, patients were evaluated during a pre-anaesthetic visit. Predictive airway assessment tests (i.e. Modified Mallampati [MMT] classification; upper lip bite test [ULBT]; mouth opening; sternomental distance; thyromental distance [TMD]; neck circumference; neck mobility; height to thyromental distance [HT/TMD]; neck circumference-to-thyromental distance [NC/TMD]) were performed on each patient and LEMON, Naguib, and MACOCHA scores were also calculated. In addition, laryngeal images were acquired and assessed for percentage of glottic opening (POGO) scores. A POGO score of zero was categorized as difficult laryngoscopy. The incidence of difficult laryngoscopy was 14.4% (35/243). Although seven predictive airway assessments (i.e. MMT classification, ULBT, mouth opening, HT/TMD, NC/TMD, and the LEMON and Naguib models) predicted difficult laryngoscopy by ROC analyses, a grey zone approach showed that the parameters were inconclusive in approximately 70% of patients. From all the tests, the HT/TMD ratio showed the highest sensitivity (80.0%) and ULBT had the highest specificity (95.2%). Using the grey zone approach, all predictive airway assessment tests showed large inconclusive zones which may explain previous inconsistent results in the prediction of difficult laryngoscopy. Our results suggest that the usefulness of clinical airway evaluation tests for predicting difficult laryngoscopy remains controversial. ClinicalTrials.gov (NCT01719848). © The Author(s) 2016.

  10. Validated Loads Prediction Models for Offshore Wind Turbines for Enhanced Component Reliability

    DEFF Research Database (Denmark)

    Koukoura, Christina

    To improve the reliability of offshore wind turbines, accurate prediction of their response is required. Therefore, validation of models with site measurements is imperative. In the present thesis a 3.6MW pitch regulated-variable speed offshore wind turbine on a monopole foundation is built...... response of a boat impact. The first and second modal damping of the system during normal operation both from measurements and simulations are identified with the implementation of the Enhanced Frequency Domain Decomposition technique. The effect of damping on the side-side fatigue of the support structure...

  11. Prediction of flow in mix-proof valve by use of CFD - Validation by LDA

    DEFF Research Database (Denmark)

    Jensen, Bo Boye Busk; Friis, Alan

    2004-01-01

    This study forms the basis to achieve quantitative knowledge on the link between hydrodynamics and good hygienic design of closed processing equipment. Knowledge offlowpatterns and parameters in process equipment are required to investigate effects of hydrodynamics on cleaning processes. This study...... was done on a spherical shaped mix-proof valve (MPV). Flow were predicted by Computational Fluid Dynamics (CFD) and validated by data obtained from experiments using laser sheet visualization and laser Doppler anemometry. Correction of the measured velocities and probe location was required as refraction...

  12. Ensuring confidence in predictions: A scheme to assess the scientific validity of in silico models.

    Science.gov (United States)

    Hewitt, Mark; Ellison, Claire M; Cronin, Mark T D; Pastor, Manuel; Steger-Hartmann, Thomas; Munoz-Muriendas, Jordi; Pognan, Francois; Madden, Judith C

    2015-06-23

    The use of in silico tools within the drug development process to predict a wide range of properties including absorption, distribution, metabolism, elimination and toxicity has become increasingly important due to changes in legislation and both ethical and economic drivers to reduce animal testing. Whilst in silico tools have been used for decades there remains reluctance to accept predictions based on these methods particularly in regulatory settings. This apprehension arises in part due to lack of confidence in the reliability, robustness and applicability of the models. To address this issue we propose a scheme for the verification of in silico models that enables end users and modellers to assess the scientific validity of models in accordance with the principles of good computer modelling practice. We report here the implementation of the scheme within the Innovative Medicines Initiative project "eTOX" (electronic toxicity) and its application to the in silico models developed within the frame of this project.

  13. The incremental validity of the dark triad in predicting driving aggression.

    Science.gov (United States)

    Burtăverde, Vlad; Chraif, Mihaela; Aniţei, Mihai; Mihăilă, Teodor

    2016-11-01

    This research tested the association between the Dark Triad and driving aggression as well as the incremental validity of the Dark Triad in predicting aggressive driving and the mediation role of the Dark Triad in the relationship between Big Five personality factors and aggressive driving. 274 undergraduate students in Study 1 and 95 amateur drivers in Study 2 completed measures of the Dark Triad (Machiavellianism, Narcissism and Psychopathy), the Big Five personality factors and the aggressive driving expression. Results showed that all the Dark Triad traits were related to aggressive driving behavior in both Study 1 and Study 2 and that the Dark Triad predicted driving aggression after the effect of the Big five personality factors was controlled, with Psychopathy being the strongest predictor of driving aggression in both Study 1 and Study 2. Machiavellianism and Psychopathy mediated the relationship between Emotional Stability, Agreeableness, Conscientiousness on one hand and aggressive driving on the other hand.

  14. Predictive validity of the ASAM Patient Placement Criteria for naturalistically matched vs. mismatched alcoholism patients.

    Science.gov (United States)

    Magura, Stephen; Staines, Graham; Kosanke, Nicole; Rosenblum, Andrew; Foote, Jeffrey; DeLuca, Alexander; Bali, Priti

    2003-01-01

    This study examined the predictive validity of the ASAM Patient Placement Criteria for matching alcoholism patients to recommended levels of care. A cohort of 248 patients newly admitted to inpatient rehabilitation, intensive outpatient, or regular outpatient care was evaluated using both a computerized algorithm and a clinical evaluation protocol to determine whether they were naturalistically matched or mismatched to care. Outcomes were assessed three months after intake. One common type of undertreatment (ie, receiving regular outpatient care when intensive outpatient care was recommended) predicted poorer drinking outcomes as compared with matched treatment, independent of actual level of care received. Overtreatment did not improve outcomes. There also was a trend for better outcomes with residential vs. intensive outpatient treatment, independent of matching. Results were robust for both methods of assessment. Corroboration by more research is needed, but the ASAM Criteria show promise for reducing both detrimental undertreatment and cost-inefficient overtreatment.

  15. A six-factor model of brand personality and its predictive validity

    Directory of Open Access Journals (Sweden)

    Živanović Marko

    2017-01-01

    Full Text Available The study examines applicability and usefulness of HEXACO-based model in the description of brand personality. Following contemporary theoretical developments in human personality research, Study 1 explored the latent personality structure of 120 brands using descriptors of six personality traits as defined in HEXACO model: Honesty-Humility, Emotionality, Extraversion, Agreeableness, Conscientiousness, and Openness. The results of exploratory factor analyses have supported HEXACO personality six-factor structure to a large extent. In Study 2 we addressed the question of predictive validity of HEXACO-based brand personality. Brand personality traits, but predominantly Honesty-Humility, accounted for substantial amount of variance in prediction of important aspects of consumer-brand relationship: attitude toward brand, perceived quality of a brand, and brand loyalty. The implications of applying HEXACO-based brand personality in marketing research are discussed. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 179018 and Grant no. 175012

  16. A Validation of Subchannel Based CHF Prediction Model for Rod Bundles

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Dae-Hyun; Kim, Seong-Jin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    A large number of CHF data base were procured from various sources which included square and non-square lattice test bundles. CHF prediction accuracy was evaluated for various models including CHF lookup table method, empirical correlations, and phenomenological DNB models. The parametric effect of the mass velocity and unheated wall has been investigated from the experimental result, and incorporated into the development of local parameter CHF correlation applicable to APWR conditions. According to the CHF design criterion, the CHF should not occur at the hottest rod in the reactor core during normal operation and anticipated operational occurrences with at least a 95% probability at a 95% confidence level. This is accomplished by assuring that the minimum DNBR (Departure from Nucleate Boiling Ratio) in the reactor core is greater than the limit DNBR which accounts for the accuracy of CHF prediction model. The limit DNBR can be determined from the inverse of the lower tolerance limit of M/P that is evaluated from the measured-to-predicted CHF ratios for the relevant CHF data base. It is important to evaluate an adequacy of the CHF prediction model for application to the actual reactor core conditions. Validation of CHF prediction model provides the degree of accuracy inferred from the comparison of solution and data. To achieve a required accuracy for the CHF prediction model, it may be necessary to calibrate the model parameters by employing the validation results. If the accuracy of the model is acceptable, then it is applied to the real complex system with the inferred accuracy of the model. In a conventional approach, the accuracy of CHF prediction model was evaluated from the M/P statistics for relevant CHF data base, which was evaluated by comparing the nominal values of the predicted and measured CHFs. The experimental uncertainty for the CHF data was not considered in this approach to determine the limit DNBR. When a subchannel based CHF prediction model

  17. PET-Based Treatment Response Evaluation in Rectal Cancer: Prediction and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, Marco H.M., E-mail: marco.janssen@maastro.nl [Department of Radiation Oncology (MAASTRO), GROW Research Institute, University Medical Centre Maastricht, Maastricht (Netherlands); Oellers, Michel C.; Stiphout, Ruud G.P.M. van [Department of Radiation Oncology (MAASTRO), GROW Research Institute, University Medical Centre Maastricht, Maastricht (Netherlands); Riedl, Robert G. [Department of Pathology, University Medical Centre Maastricht, Maastricht (Netherlands); Bogaard, Jorgen van den; Buijsen, Jeroen; Lambin, Philippe; Lammering, Guido [Department of Radiation Oncology (MAASTRO), GROW Research Institute, University Medical Centre Maastricht, Maastricht (Netherlands)

    2012-02-01

    Purpose: To develop a positron emission tomography (PET)-based response prediction model to differentiate pathological responders from nonresponders. The predictive strength of the model was validated in a second patient group, treated and imaged identical to the patients on which the predictive model was based. Methods and Materials: Fifty-one rectal cancer patients were prospectively included in this study. All patients underwent fluorodeoxyglucose (FDG) PET-computed tomography (CT) imaging both before the start of chemoradiotherapy (CRT) and after 2 weeks of treatment. Preoperative treatment with CRT was followed by a total mesorectal excision. From the resected specimen, the tumor regression grade (TRG) was scored according to the Mandard criteria. From one patient group (n = 30), the metabolic treatment response was correlated with the pathological treatment response, resulting in a receiver operating characteristic (ROC) curve based cutoff value for the reduction of maximum standardized uptake value (SUV{sub max}) within the tumor to differentiate pathological responders (TRG 1-2) from nonresponders (TRG 3-5). The applicability of the selected cutoff value for new patients was validated in a second patient group (n = 21). Results: When correlating the metabolic and pathological treatment response for the first patient group using ROC curve analysis (area under the curve = 0.98), a cutoff value of 48% SUV{sub max} reduction was selected to differentiate pathological responders from nonresponders (specificity of 100%, sensitivity of 64%). Applying this cutoff value to the second patient group resulted in a specificity and sensitivity of, respectively, 93% and 83%, with only one of the pathological nonresponders being false positively predicted as pathological responding. Conclusions: For rectal cancer, an accurate PET-based prediction of the pathological treatment response is feasible already after 2 weeks of CRT. The presented predictive model could be used to

  18. External validation of anti-Müllerian hormone based prediction of live birth in assisted conception

    Directory of Open Access Journals (Sweden)

    Khader Amani

    2013-01-01

    Full Text Available Abstract Background Chronological age and oocyte yield are independent determinants of live birth in assisted conception. Anti-Müllerian hormone (AMH is strongly associated with oocyte yield after controlled ovarian stimulation. We have previously assessed the ability of AMH and age to independently predict live birth in an Italian assisted conception cohort. Herein we report the external validation of the nomogram in 822 UK first in vitro fertilization (IVF cycles. Methods Retrospective cohort consisting of 822 patients undergoing their first IVF treatment cycle at Glasgow Centre for Reproductive Medicine. Analyses were restricted to women aged between 25 and 42 years of age. All women had an AMH measured prior to commencing their first IVF cycle. The performance of the model was assessed; discrimination by the area under the receiver operator curve (ROCAUC and model calibration by the predicted probability versus observed probability. Results Live births occurred in 29.4% of the cohort. The observed and predicted outcomes showed no evidence of miscalibration (p = 0.188. The ROCAUC was 0.64 (95% CI: 0.60, 0.68, suggesting moderate and similar discrimination to the original model. The ROCAUC for a continuous model of age and AMH was 0.65 (95% CI 0.61, 0.69, suggesting that the original categories of AMH were appropriate. Conclusions We confirm by external validation that AMH and age are independent predictors of live birth. Although the confidence intervals for each category are wide, our results support the assessment of AMH in larger cohorts with detailed baseline phenotyping for live birth prediction.

  19. Predictive validity of the physical disorders axis of the DSM multiaxial diagnostic system.

    Science.gov (United States)

    Saavedra, J E; Mezzich, J E; Salloum, I M; Kirisci, L

    2001-07-01

    This paper reports on the predictive validity of the physical disorders axis (axis III) of the DSM multiaxial diagnostic system at 3-year follow-up. A total of 515 general psychiatric patients were assessed with a semistructured procedure that covers all DSM-III diagnoses and axes, and were subsequently followed up for 3 years. Outcome was assessed with several measures of adaptive functioning. Baseline axis III was analyzed according to a) presence of any physical disorder, b) the number of these, c) presence of major chronic physical disorders (MCPD), and d) the number of these. Prediction of impairment in functioning (Strauss-Carpenter Scale), derived from baseline axis III, ranged from a correlation coefficient of .18 when expressed as the presence of any physical disorder to .35 when represented by the number of MCPD. Furthermore, within patients with specific psychiatric disorders, it was found that number of MCPD reached a predictive validity of .55 for patients with dysthymic disorders, .44 for those with anxiety disorders, and .41 for those with major depression. Comparative multiple regression analyses, controlling for demographic and clinical variables, showed that the number of MCPD at baseline was the most important predictor of functioning outcome among patients with dysthymic disorders and major depression. The number of MCPD experienced by general psychiatric patients seems to be an important predictor of future functioning, particularly for patients with certain psychiatric disorders. This points out the importance of considering the relationship between psychiatric and MCPD when conducting systematic clinical assessments towards the prediction of course and outcome.

  20. Validating a Predictive Model of Acute Advanced Imaging Biomarkers in Ischemic Stroke.

    Science.gov (United States)

    Bivard, Andrew; Levi, Christopher; Lin, Longting; Cheng, Xin; Aviv, Richard; Spratt, Neil J; Lou, Min; Kleinig, Tim; O'Brien, Billy; Butcher, Kenneth; Zhang, Jingfen; Jannes, Jim; Dong, Qiang; Parsons, Mark

    2017-03-01

    Advanced imaging to identify tissue pathophysiology may provide more accurate prognostication than the clinical measures used currently in stroke. This study aimed to derive and validate a predictive model for functional outcome based on acute clinical and advanced imaging measures. A database of prospectively collected sub-4.5 hour patients with ischemic stroke being assessed for thrombolysis from 5 centers who had computed tomographic perfusion and computed tomographic angiography before a treatment decision was assessed. Individual variable cut points were derived from a classification and regression tree analysis. The optimal cut points for each assessment variable were then used in a backward logic regression to predict modified Rankin scale (mRS) score of 0 to 1 and 5 to 6. The variables remaining in the models were then assessed using a receiver operating characteristic curve analysis. Overall, 1519 patients were included in the study, 635 in the derivation cohort and 884 in the validation cohort. The model was highly accurate at predicting mRS score of 0 to 1 in all patients considered for thrombolysis therapy (area under the curve [AUC] 0.91), those who were treated (AUC 0.88) and those with recanalization (AUC 0.89). Next, the model was highly accurate at predicting mRS score of 5 to 6 in all patients considered for thrombolysis therapy (AUC 0.91), those who were treated (0.89) and those with recanalization (AUC 0.91). The odds ratio of thrombolysed patients who met the model criteria achieving mRS score of 0 to 1 was 17.89 (4.59-36.35, Pischemic stroke. © 2017 American Heart Association, Inc.

  1. Validated QSAR prediction of OH tropospheric degradation of VOCs: splitting into training-test sets and consensus modeling.

    Science.gov (United States)

    Gramatica, Paola; Pilutti, Pamela; Papa, Ester

    2004-01-01

    The rate constant for hydroxyl radical tropospheric degradation of 460 heterogeneous organic compounds is predicted by QSAR modeling. The applied Multiple Linear Regression is based on a variety of theoretical molecular descriptors, selected by the Genetic Algorithms-Variable Subset Selection (GA-VSS) procedure. The models were validated for predictivity by both internal and external validation. For the external validation two splitting approaches, D-optimal Experimental Design and Kohonen Artificial Neural Networks (K-ANN), were applied to the original data set to compare the two methodologies. We emphasize that external validation is the only way to establish a reliable QSAR model for predictive purposes. Predicted data by consensus modeling from different models are also proposed. Copyright 2004 American Chemical Society

  2. Reduction of SEM noise and extended application to prediction of CD uniformity and its experimental validation

    Science.gov (United States)

    Kim, Hoyeon; Hwang, Chan; Oh, Seok-hwan; Yeo, Jeongho; Kim, Young hee

    2011-03-01

    As the design rule of Integrated Circuits(IC) becomes smaller, the precise measurement of Critical Dimension (CD) of features and minimization of deviation in CD measured becomes a vital issue. In this paper, a simple frequency analysis method to extract the noise from SEM images was used to evaluate the contribution of SEM noise in CD Uniformity. Multiple SEM images of simple Line and Space (L/S) patterns were analyzed and a model of frequency profile (Power Spectrum Density (PSD) model) was made using an offline analyzing tool based on Matlab®. From this profile, white noise and 1/f profile were separated. Noises are eliminated to generate a noise reduced PSD profile to make CD results. The contribution of white noise on CD measurement can be assessed using Line Width Roughness (LWR) measurement. Furthermore, CD uniformity can be also predicted from the model. This prediction is based on an assumption that CD uniformity is equal to LWR if the inspection area is extended to infinity and appropriate sampling method is applied. The results showed that the contribution of white noise on LWR can be up to around 70% (in power) without any noise reduction measures (sum line averaging) after imaging in photo resist image. For experimental validation, CD uniformity is predicted from the model for different measurement conditions and compared with real measurement. For a result, CD uniformity prediction (3sigma) from the model shows within 20% in accuracy with real CD uniformity value measured from the photo resist image.

  3. Prediction of valid acidity in intact apples with Fourier transform near infrared spectroscopy

    Institute of Scientific and Technical Information of China (English)

    LIU Yan-de; YING Yi-bin; FU Xia-ping

    2005-01-01

    To develop nondestructive acidity prediction for intact Fuji apples, the potential of Fourier transform near infrared(FT-NIR) method with fiber optics in interactance mode was investigated. Interactance in the 800 nm to 2619 nm region was measured for intact apples, harvested from early to late maturity stages. Spectral data were analyzed by two multivariate calibration techniques including partial least squares (PLS) and principal component regression (PCR) methods. A total of 120 Fuji apples were tested and 80 of them were used to form a calibration data set. The influences of different data preprocessing and spectra treatments were also quantified. Calibration models based on smoothing spectra were slightly worse than that based on derivative spectra, and the best result was obtained when the segment length was 5 nm and the gap size was 10 points. Depending on data preprocessing and PLS method, the best prediction model yielded correlation coefficient of determination (r2) of 0.759, low root mean square error of prediction (RMSEP) of 0.0677, low root mean square error of calibration (RMSEC) of 0.0562. The results indicated the feasibility of FT-NIR spectral analysis for predicting apple valid acidity in a nondestructive way.

  4. Predicting NCLEX-RN Success: the Seventh Validity Study HESI Exit exam.

    Science.gov (United States)

    Young, Anne; Willson, Pamela

    2012-01-01

    The findings of six previously conducted studies indicated that the HESI (E) was highly accurate in predicting NCLEX-RN success. The purpose of this study-the seventh study to investigate the validity of the E-was to examine the accuracy of three parallel versions of the Ein predicting licensure success and to describe program practices regarding E benchmark scores, remediation programs, and retesting policies. The findings of this study again indicated that the E was highly accurate in predicting NCLEX-RN success. Additionally, all three versions of the E were found to have a predictive accuracy above 90%. The most common E benchmark score designated by faculty at the participating schools was 850, and most schools required students to retest with different versions of the E until the faculty-designated E benchmark score was achieved. Remediation seemed to be effective in raising students' E scores, and it was recommended that future research investigate the effectiveness of specific remediation strategies.

  5. Validation test for CAP88 predictions of tritium dispersion at Los Alamos National Laboratory.

    Science.gov (United States)

    Michelotti, Erika; Green, Andrew; Whicker, Jeffrey; Eisele, William; Fuehne, David; McNaughton, Michael

    2013-08-01

    Gaussian plume models, such as CAP88, are used regularly for estimating downwind concentrations from stack emissions. At many facilities, the U.S. Environmental Protection Agency (U.S. EPA) requires that CAP88 be used to demonstrate compliance with air quality regulations for public protection from emissions of radionuclides. Gaussian plume models have the advantage of being relatively simple and their use pragmatic; however, these models are based on simplifying assumptions and generally they are not capable of incorporating dynamic meteorological conditions or complex topography. These limitations encourage validation tests to understand the capabilities and limitations of the model for the specific application. Los Alamos National Laboratory (LANL) has complex topography but is required to use CAP88 for compliance with the Clean Air Act Subpart H. The purpose of this study was to test the accuracy of the CAP88 predictions against ambient air measurements using released tritium as a tracer. Stack emissions of tritium from two LANL stacks were measured and the dispersion modeled with CAP88 using local meteorology. Ambient air measurements of tritium were made at various distances and directions from the stacks. Model predictions and ambient air measurements were compared over the course of a full year's data. Comparative results were consistent with other studies and showed the CAP88 predictions of downwind tritium concentrations were on average about three times higher than those measured, and the accuracy of the model predictions were generally more consistent for annual averages than for bi-weekly data.

  6. Prediction of prostate cancer recurrence using quantitative phase imaging: Validation on a general population

    Science.gov (United States)

    Sridharan, Shamira; Macias, Virgilia; Tangella, Krishnarao; Melamed, Jonathan; Dube, Emily; Kong, Max Xiangtian; Kajdacsy-Balla, André; Popescu, Gabriel

    2016-09-01

    Prediction of biochemical recurrence risk of prostate cancer following radical prostatectomy is critical for determining whether the patient would benefit from adjuvant treatments. Various nomograms exist today for identifying individuals at higher risk for recurrence; however, an optimistic under-estimation of recurrence risk is a common problem associated with these methods. We previously showed that anisotropy of light scattering measured using quantitative phase imaging, in the stromal layer adjacent to cancerous glands, is predictive of recurrence. That nested-case controlled study consisted of specimens specifically chosen such that the current prognostic methods fail. Here we report on validating the utility of optical anisotropy for prediction of prostate cancer recurrence in a general population of 192 patients, with 17% probability of recurrence. Our results show that our method can identify recurrent cases with 73% sensitivity and 72% specificity, which is comparable to that of CAPRA-S, a current state of the art method, in the same population. However, our results show that optical anisotropy outperforms CAPRA-S for patients with Gleason grades 7–10. In essence, we demonstrate that anisotropy is a better biomarker for identifying high-risk cases, while Gleason grade is better suited for selecting non-recurrence. Therefore, we propose that anisotropy and current techniques be used together to maximize prediction accuracy.

  7. Validity of the SAT® for Predicting First-Year Grades: 2010 SAT Validity Sample. Statistical Report 2013-2

    Science.gov (United States)

    Patterson, Brian F.; Mattern, Krista D.

    2013-01-01

    The continued accumulation of validity evidence for the core uses of educational assessments is critical to ensure that proper inferences will be made for those core purposes. To that end, the College Board has continued to follow previous cohorts of college students and this report provides updated validity evidence for using the SAT to predict…

  8. External validation of prognostic models to predict risk of gestational diabetes mellitus in one Dutch cohort : prospective multicentre cohort study

    NARCIS (Netherlands)

    Lamain-de Ruiter, Marije; Kwee, Anneke; Naaktgeboren, Christiana A; de Groot, Inge; Evers, Inge M; Groenendaal, Floris; Hering, Yolanda R; Huisjes, Anjoke J M; Kirpestein, Cornel; Monincx, Wilma M; Siljee, Jacqueline E; Van 't Zelfde, Annewil; van Oirschot, Charlotte M; Vankan-Buitelaar, Simone A; Vonk, Mariska A A W; Wiegers, Therese A; Zwart, Joost J; Franx, Arie; Moons, Karel G M; Koster, Maria P H

    2016-01-01

    OBJECTIVE: To perform an external validation and direct comparison of published prognostic models for early prediction of the risk of gestational diabetes mellitus, including predictors applicable in the first trimester of pregnancy. DESIGN: External validation of all published prognostic models in

  9. A new test set for validating predictions of protein-ligand interaction.

    Science.gov (United States)

    Nissink, J Willem M; Murray, Chris; Hartshorn, Mike; Verdonk, Marcel L; Cole, Jason C; Taylor, Robin

    2002-12-01

    We present a large test set of protein-ligand complexes for the purpose of validating algorithms that rely on the prediction of protein-ligand interactions. The set consists of 305 complexes with protonation states assigned by manual inspection. The following checks have been carried out to identify unsuitable entries in this set: (1) assessing the involvement of crystallographically related protein units in ligand binding; (2) identification of bad clashes between protein side chains and ligand; and (3) assessment of structural errors, and/or inconsistency of ligand placement with crystal structure electron density. In addition, the set has been pruned to assure diversity in terms of protein-ligand structures, and subsets are supplied for different protein-structure resolution ranges. A classification of the set by protein type is available. As an illustration, validation results are shown for GOLD and SuperStar. GOLD is a program that performs flexible protein-ligand docking, and SuperStar is used for the prediction of favorable interaction sites in proteins. The new CCDC/Astex test set is freely available to the scientific community (http://www.ccdc.cam.ac.uk).

  10. External validation of the MRI-DRAGON score: early prediction of stroke outcome after intravenous thrombolysis.

    Directory of Open Access Journals (Sweden)

    Guillaume Turc

    Full Text Available The aim of our study was to validate in an independent cohort the MRI-DRAGON score, an adaptation of the (CT- DRAGON score to predict 3-month outcome in acute ischemic stroke patients undergoing MRI before intravenous thrombolysis (IV-tPA.We reviewed consecutive (2009-2013 anterior circulation stroke patients treated within 4.5 hours by IV-tPA in the Lille stroke unit (France, where MRI is the first-line pretherapeutic work-up. We assessed the discrimination and calibration of the MRI-DRAGON score to predict poor 3-month outcome, defined as modified Rankin Score >2, using c-statistic and the Hosmer-Lemeshow test, respectively.We included 230 patients (mean ±SD age 70.4±16.0 years, median [IQR] baseline NIHSS 8 [5]-[14]; poor outcome in 78(34% patients. The c-statistic was 0.81 (95%CI 0.75-0.87, and the Hosmer-Lemeshow test was not significant (p = 0.54.The MRI-DRAGON score showed good prognostic performance in the external validation cohort. It could therefore be used to inform the patient's relatives about long-term prognosis and help to identify poor responders to IV-tPA alone, who may be candidates for additional therapeutic strategies, if they are otherwise eligible for such procedures based on the institutional criteria.

  11. Vibrations inside buildings due to subway railway traffic. Experimental validation of a comprehensive prediction model.

    Science.gov (United States)

    Lopes, Patrícia; Ruiz, Jésus Fernández; Alves Costa, Pedro; Medina Rodríguez, L; Cardoso, António Silva

    2016-10-15

    The present paper focuses on the experimental validation of a numerical approach previously proposed by the authors for the prediction of vibrations inside buildings due to railway traffic in tunnels. The numerical model is based on the concept of dynamic substructuring and is composed by three autonomous models to simulate the following main parts of the problem: i) generation of vibrations (train-track interaction); ii) propagation of vibrations (track-tunnel-ground system); iii) reception of vibrations (building coupled to the ground). The experimental validation consists in the comparison between the results predicted by the proposed numerical model and the measurements performed inside a building due to the railway traffic in a shallow tunnel located in Madrid. Apart from the brief description of the numerical model and of the case study, the main options and simplifications adopted on the numerical modeling strategy are discussed. The balance adopted between accuracy and simplicity of the numerical approach proved to be a path to follow in order to transfer knowledge to engineering practice. Finally, the comparison between numerical and experimental results allowed finding a good agreement between both, fact that ensures the ability of the proposed modeling strategy to deal with real engineering practical problems. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. A validated model of passive skeletal muscle to predict force and intramuscular pressure.

    Science.gov (United States)

    Wheatley, Benjamin B; Odegard, Gregory M; Kaufman, Kenton R; Haut Donahue, Tammy L

    2016-12-31

    The passive properties of skeletal muscle are often overlooked in muscle studies, yet they play a key role in tissue function in vivo. Studies analyzing and modeling muscle passive properties, while not uncommon, have never investigated the role of fluid content within the tissue. Additionally, intramuscular pressure (IMP) has been shown to correlate with muscle force in vivo and could be used to predict muscle force in the clinic. In this study, a novel model of skeletal muscle was developed and validated to predict both muscle stress and IMP under passive conditions for the New Zealand White Rabbit tibialis anterior. This model is the first to include fluid content within the tissue and uses whole muscle geometry. A nonlinear optimization scheme was highly effective at fitting model stress output to experimental stress data (normalized mean square error or NMSE fit value of 0.993) and validation showed very good agreement to experimental data (NMSE fit values of 0.955 and 0.860 for IMP and stress, respectively). While future work to include muscle activation would broaden the physiological application of this model, the passive implementation could be used to guide surgeries where passive muscle is stretched.

  13. Predictive validity of health-related fitness in youth: a systematic review.

    Science.gov (United States)

    Ruiz, J R; Castro-Piñero, J; Artero, E G; Ortega, F B; Sjöström, M; Suni, J; Castillo, M J

    2009-12-01

    The objective of the present systematic review was to investigate whether physical fitness in childhood and adolescence is a predictor of cardiovascular disease (CVD) risk factors, events and syndromes, quality of life and low back pain later in life. Physical fitness-related components were: cardiorespiratory fitness, musculoskeletal fitness, motor fitness and body composition. Adiposity was considered as both exposure and outcome. The results of 42 studies reporting the predictive validity of health-related physical fitness for CVD risk factors, events and syndromes as well as the results of five studies reporting the predictive validity of physical fitness for low back pain in children and adolescents were summarised. Strong evidence was found indicating that higher levels of cardiorespiratory fitness in childhood and adolescence are associated with a healthier cardiovascular profile later in life. Muscular strength improvements from childhood to adolescence are negatively associated with changes in overall adiposity. A healthier body composition in childhood and adolescence is associated with a healthier cardiovascular profile later in life and with a lower risk of death. The evidence was moderate for the association between changes in cardiorespiratory fitness and CVD risk factors, and between cardiorespiratory fitness and the risk of developing the metabolic syndrome and arterial stiffness. Moderate evidence on the lack of a relationship between body composition and low back pain was found. Due to a limited number of studies, inconclusive evidence emerged for a relationship between muscular strength or motor fitness and CVD risk factors, and between flexibility and low back pain.

  14. Validity of different prediction equations of the maximum load in mixed martial arts athletes

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    Jairo Laécio Guerra Filho

    2014-12-01

    Full Text Available The purpose of this study was to investigate the validity of different prediction equations to the one maximum repetition (1-RM test at the bench press exercise (BP with bar in mixed martial arts (MMA athletes. The sample was composed by 19 male MMA athletes (27.68 ± 6.19 years. The data collection was performed in two different moments: 1 in 1-RM test; 2 in submaximal test and their respective numbers of repetitions. The paired-sample t test was performed and was noted that, among the six equations compared with the 1-RM test, only the Adams (p= 0.337 and O’Conner’s (p= 0.250 equations showed no significant differences. However, there were high Pearson correlation and intraclass correlation coefficients (r= 0.924, ICC= 0.924; r= 0.944, ICC= 0.944, respectively. Nevertheless, all equations showed high correlations that ranged between 0.854 and 0.944. In conclusion, for estimation of 1-RM, the predictive equations based on Adams and O'Conner’s are valid in MMA athletes.

  15. Predictive validity of the post-enrolment English language assessment tool for commencing undergraduate nursing students.

    Science.gov (United States)

    Glew, Paul J; Hillege, Sharon P; Salamonson, Yenna; Dixon, Kathleen; Good, Anthony; Lombardo, Lien

    2015-12-01

    Nursing students with English as an additional language (EAL) may underperform academically. The post-enrolment English language assessment (PELA) is used in literacy support, but its predictive validity in identifying those at risk of underperformance remains unknown. To validate a PELA, as a predictor of academic performance. Prospective survey design. The study was conducted at a university located in culturally and linguistically diverse areas of western Sydney, Australia. Commencing undergraduate nursing students who were Australian-born (n=1323, 49.6%) and born outside of Australia (n=1346, 50.4%) were recruited for this study. The 2669 (67% of 3957) participants provided consent and completed a first year nursing unit that focussed on developing literacy skills. Between 2010 and 2013, commencing students completed the PELA and English language acculturation scale (ELAS), a previously validated instrument. The grading levels of the PELA tool were: Level 1 (proficient), Level 2 (borderline), and Level 3 (poor, and requiring additional support). Participants with a PELA Level 2 or 3 were more likely to be: a) non-Australian-born (χ(2): 520.6, df: 2, pGPA (χ(2): 100.8, df: 2, pacademic underachievement. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  16. Determining relative importance of variables in developing and validating predictive models

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    Atenafu Eshetu G

    2009-09-01

    Full Text Available Abstract Background Multiple regression models are used in a wide range of scientific disciplines and automated model selection procedures are frequently used to identify independent predictors. However, determination of relative importance of potential predictors and validating the fitted models for their stability, predictive accuracy and generalizability are often overlooked or not done thoroughly. Methods Using a case study aimed at predicting children with acute lymphoblastic leukemia (ALL who are at low risk of Tumor Lysis Syndrome (TLS, we propose and compare two strategies, bootstrapping and random split of data, for ordering potential predictors according to their relative importance with respect to model stability and generalizability. We also propose an approach based on relative increase in percentage of explained variation and area under the Receiver Operating Characteristic (ROC curve for developing models where variables from our ordered list enter the model according to their importance. An additional data set aimed at identifying predictors of prostate cancer penetration is also used for illustrative purposes. Results Age is chosen to be the most important predictor of TLS. It is selected 100% of the time using the bootstrapping approach. Using the random split method, it is selected 99% of the time in the training data and is significant (at 5% level 98% of the time in the validation data set. This indicates that age is a stable predictor of TLS with good generalizability. The second most important variable is white blood cell count (WBC. Our methods also identified an important predictor of TLS that was otherwise omitted if relying on any of the automated model selection procedures alone. A group at low risk of TLS consists of children younger than 10 years of age, without T-cell immunophenotype, whose baseline WBC is 9/L and palpable spleen is Conclusion Our model selection procedures based on bootstrap re-sampling and

  17. A validated CFD model to predict O₂ and CO₂ transfer within hollow fiber membrane oxygenators.

    Science.gov (United States)

    Hormes, Marcus; Borchardt, Ralf; Mager, Ilona; Rode, Thomas Schmitz; Behr, Marek; Steinseifer, Ulrich

    2011-03-01

    Hollow fiber oxygenators provide gas exchange to and from the blood during heart surgery or lung recovery. Minimal fiber surface area and optimal gas exchange rate may be achieved by optimization of hollow fiber shape and orientation (1). In this study, a modified CFD model is developed and validated with a specially developed micro membrane oxygenator (MicroMox). The MicroMox was designed in such a way that fiber arrangement and bundle geometry are highly reproducible and potential flow channeling is avoided, which is important for the validation. Its small size (V(Fluid)=0.04 mL) allows the simulation of the entire bundle of 120 fibers. A non-Newtonian blood model was used as simulation fluid. Physical solubility and chemical bond of O₂ and CO₂ in blood was represented by the numerical model. Constant oxygen partial pressure at the pores of the fibers and a steady state flow field was used to calculate the mass transport. In order to resolve the entire MicroMox fiber bundle, the mass transport was simulated for symmetric geometry sections in flow direction. In vitro validation was achieved by measurements of the gas transfer rates of the MicroMox. All measurements were performed according to DIN EN 12022 (2) using porcine blood. The numerical simulation of the mass transfer showed good agreement with the experimental data for different mass flows and constant inlet partial pressures. Good agreement could be achieved for two different fiber configurations. Thus, it was possible to establish a validated model for the prediction of gas exchange in hollow fiber oxygenators.

  18. Scoring system development and validation for prediction choledocholithiasis before open cholecystectomy

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    Pejović Tomislav

    2015-01-01

    Full Text Available Introduction. Accurate precholecystectomy detection of concurrent asymptomatic common bile duct stones (CBDS is key in the clinical decision-making process. The standard preoperative methods used to diagnose these patients are often not accurate enough. Objective. The aim of the study was to develop a scoring model that would predict CBDS before open cholecystectomy. Methods. We retrospectively collected preoperative (demographic, biochemical, ultrasonographic and intraoperative (intraoperative cholangiography data for 313 patients at the department of General Surgery at Gornji Milanovac from 2004 to 2007. The patients were divided into a derivation (213 and a validation set (100. Univariate and multivariate regression analysis was used to determine independent predictors of CBDS. These predictors were used to develop scoring model. Various measures for the assessment of risk prediction models were determined, such as predictive ability, accuracy, the area under the receiver operating characteristic curve (AUC, calibration and clinical utility using decision curve analysis. Results. In a univariate analysis, seven risk factors displayed significant correlation with CBDS. Total bilirubin, alkaline phosphatase and bile duct dilation were identified as independent predictors of choledocholithiasis. The resultant total possible score in the derivation set ranged from 7.6 to 27.9. Scoring model shows good discriminatory ability in the derivation and validation set (AUC 94.3 and 89.9%, respectively, excellent accuracy (95.5%, satisfactory calibration in the derivation set, similar Brier scores and clinical utility in decision curve analysis. Conclusion. Developed scoring model might successfully estimate the presence of choledocholithiasis in patients planned for elective open cholecystectomy. [Projekat Ministarstva nauke Republike Srbije, br. 175014

  19. Prediction and Validation of Native and Engineered Cas9 Guide Sequences.

    Science.gov (United States)

    Briner, Alexandra E; Henriksen, Emily D; Barrangou, Rodolphe

    2016-07-01

    Cas9-based technologies rely on native elements of Type II CRISPR-Cas bacterial immune systems, including the trans-activating CRISPR RNA (tracrRNA), CRISPR RNA (crRNA), Cas9 protein, and protospacer-adjacent motif (PAM). The tracrRNA and crRNA form an RNA duplex that guides the Cas9 endonuclease to complementary nucleic acid sequences. Mechanistically, Cas9 initiates interactions by binding to the target PAM sequence and interrogating the target DNA in a 3'-to-5' manner. Complementarity between the guide RNA and the target DNA is key. In natural systems, precise cleavage occurs when the target DNA sequence contains a PAM flanking a sequence homologous to the crRNA spacer sequence. Currently, the majority of commercial Cas9-based genome-editing tools are derived from the Type II CRISPR-Cas system of Streptococcus pyogenes However, a diverse set of Type II CRISPR-Cas systems exist in nature that are potentially valuable for genome engineering applications. Exploitation of these systems requires prediction and validation of both native and engineered dual and single guide RNAs to drive Cas9 functionality. Here, we discuss how to identify the elements of these immune systems to develop next-generation Cas9-based genome-editing tools. We first discuss how to predict tracrRNA sequences and suggest a method for designing single guide RNAs containing only critical structural modules. We then outline how to predict the PAM sequence, which is crucial for determining potential targets for Cas9. Finally, validation of the system elements through transcriptome analysis and interference assays is essential for developing next-generation Cas9-based genome-editing tools.

  20. iROS-gPseKNC: Predicting replication origin sites in DNA by incorporating dinucleotide position-specific propensity into general pseudo nucleotide composition

    Science.gov (United States)

    Xiao, Xuan; Ye, Han-Xiao; Liu, Zi; Jia, Jian-Hua; Chou, Kuo-Chen

    2016-01-01

    DNA replication, occurring in all living organisms and being the basis for biological inheritance, is the process of producing two identical replicas from one original DNA molecule. To in-depth understand such an important biological process and use it for developing new strategy against genetics diseases, the knowledge of duplication origin sites in DNA is indispensible. With the explosive growth of DNA sequences emerging in the postgenomic age, it is highly desired to develop high throughput tools to identify these regions purely based on the sequence information alone. In this paper, by incorporating the dinucleotide position-specific propensity information into the general pseudo nucleotide composition and using the random forest classifier, a new predictor called iROS-gPseKNC was proposed. Rigorously cross–validations have indicated that the proposed predictor is significantly better than the best existing method in sensitivity, specificity, overall accuracy, and stability. Furthermore, a user-friendly web-server for iROS-gPseKNC has been established at http://www.jci-bioinfo.cn/iROS-gPseKNC, by which users can easily get their desired results without the need to bother the complicated mathematics, which were presented just for the integrity of the methodology itself. PMID:27147572

  1. DSM-5 antisocial personality disorder: predictive validity in a prison sample.

    Science.gov (United States)

    Edens, John F; Kelley, Shannon E; Lilienfeld, Scott O; Skeem, Jennifer L; Douglas, Kevin S

    2015-04-01

    Symptoms of antisocial personality disorder (ASPD), particularly remorselessness, are frequently introduced in legal settings as a risk factor for future violence in prison, despite a paucity of research on the predictive validity of this disorder. We examined whether an ASPD diagnosis or symptom-criteria counts could prospectively predict any form of institutional misconduct, as well as aggressive and violent infractions among newly admitted prisoners. Adult male (n = 298) and female (n = 55) offenders were recruited from 4 prison systems across the United States. At the time of study enrollment, diagnostic information was collected using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; APA, 1994) Axis II Personality Disorders (SCID-II; First, Gibbon, Spitzer, Williams, & Benjamin, 1997) supplemented by a detailed review of official records. Disciplinary records were obtained from inmates' respective prisons covering a 1-year period following study enrollment and misconduct was categorized hierarchically as any (general), aggressive (verbal/physical), or violent (physical). Dichotomous ASPD diagnoses and adult symptom-criteria counts did not significantly predict institutional misconduct across our 3 outcome variables, with effect sizes being close to 0 in magnitude. The symptom of remorselessness in particular showed no relation to future misconduct in prison. Childhood symptom counts of conduct disorder demonstrated modest predictive utility. Our results offer essentially no support for the claim that ASPD diagnoses can predict institutional misconduct in prison, regardless of the number of adult symptoms present. In forensic contexts, testimony that an ASPD diagnosis identifies defendants who will pose a serious threat while incarcerated in prison presently lacks any substantial scientific foundation.

  2. Validation of the prostate health index in a predictive model of prostate cancer.

    Science.gov (United States)

    Sanchís-Bonet, A; Barrionuevo-González, M; Bajo-Chueca, A M; Pulido-Fonseca, L; Ortega-Polledo, L E; Tamayo-Ruiz, J C; Sánchez-Chapado, M

    2017-08-12

    To validate and analyse the clinical usefulness of a predictive model of prostate cancer that incorporates the biomarker «[-2] pro prostate-specific antigen» using the prostate health index (PHI) in decision making for performing prostate biopsies. We isolated serum from 197 men with an indication for prostate biopsy to determine the total prostate-specific antigen (tPSA), the free PSA fraction (fPSA) and the [-2] proPSA (p2PSA). The PHI was calculated as p2PSA/fPSA×√tPSA. We created 2 predictive models that incorporated clinical variables along with tPSA or PHI. The performance of PHI was assessed with a discriminant analysis using receiver operating characteristic curves, internal calibration and decision curves. The areas under the curve for the tPSA and PHI models were 0.71 and 0.85, respectively. The PHI model showed a better ability to discriminate and better calibration for predicting prostate cancer but not for predicting a Gleason score in the biopsy ≥7. The decision curves showed a greater net benefit with the PHI model for diagnosing prostate cancer when the probability threshold was 15-35% and greater savings (20%) in the number of biopsies. The incorporation of p2PSA through PHI in predictive models of prostate cancer improves the accuracy of the risk stratification and helps in the decision-making process for performing prostate biopsies. Copyright © 2017 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. External Validation of Models for Prediction of Lymph Node Metastasis in Urothelial Carcinoma of the Bladder.

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    Ja Hyeon Ku

    Full Text Available To externally validate models to predict LN metastsis; Karakiewicz nomogram, clinical nodal staging score (cNSS, and pathologic nodal staging score (pNSS using a different cohort.Clinicopathologic data from 500 patients who underwent radical cystectomy and pelvic lymphadenectomy were analyzed. The overall predictive values of models were compared with the criteria of overall performance, discrimination, calibration, and clinical usefulness.Presence of pN+ stages was recorded in 117 patients (23.4%. Agreement between clinical and pathologic stage was noted in 174 (34.8%. Based on Nagelkerke's peudo-R2 and brier score, pNSS demonstrated best overall performance. Area under the receiver operating characteristics curve, showed that pNSS had the best discriminatory ability. In all models, calibration was on average correct (calibration-in-the-large coefficient = zero. On decision curve analysis, pNSS performed better than other models across a wide range of threshold probabilities.When compared to pNSS, current precystectomy models such as the Karakiewicz nomogram and cNSS cannot predict the probability of LN metastases accurately. The findings suggest that the application of pNSS to Asian patients is feasible.

  4. Incremental validity of positive orientation: predictive efficiency beyond the five-factor model

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    Łukasz Roland Miciuk

    2016-05-01

    Full Text Available Background The relation of positive orientation (a basic predisposition to think positively of oneself, one’s life and one’s future and personality traits is still disputable. The purpose of the described research was to verify the hypothesis that positive orientation has predictive efficiency beyond the five-factor model. Participants and procedure One hundred and thirty participants (at the mean age M = 24.84 completed the following questionnaires: the Self-Esteem Scale (SES, the Satisfaction with Life Scale (SWLS, the Life Orientation Test-Revised (LOT-R, the Positivity Scale (P-SCALE, the NEO Five Factor Inventory (NEO-FFI, the Self-Concept Clarity Scale (SCC, the Generalized Self-Efficacy Scale (GSES and the Life Engagement Test (LET. Results The introduction of positive orientation as an additional predictor in the second step of regression analyses led to better prediction of the following variables: purpose in life, self-concept clarity and generalized self-efficacy. This effect was the strongest for predicting purpose in life (i.e. 14% increment of the explained variance. Conclusions The results confirmed our hypothesis that positive orientation can be characterized by incremental validity – its inclusion in the regression model (in addition to the five main factors of personality increases the amount of explained variance. These findings may provide further evidence for the legitimacy of measuring positive orientation and personality traits separately.

  5. Validation of a Predictive Model to Identify Patients at High Risk for Hospital Readmission.

    Science.gov (United States)

    Spiva, LeeAnna; Hand, Marti; VanBrackle, Lewis; McVay, Frank

    2016-01-01

    Hospital readmission is an adverse patient outcome that is serious, common, and costly. For hospitals, identifying patients at risk for hospital readmission is a priority to reduce costs and improve care. The purposes were to validate a predictive algorithm to identify patients at a high risk for preventable hospital readmission within 30 days after discharge and determine if additional risk factors enhance readmission predictability. A retrospective study was conducted on a randomized sample of 598 patients discharged from a Southeast community hospital. Data were collected from the organization's database and manually abstracted from the electronic medical record using a structured tool. Two separate logistic regression models were fit for the probability of readmission within 30 days after discharge. The first model used the LACE index as the predictor variable, and the second model used the LACE index with additional risk factors. The two models were compared to determine if additional risk factors increased the model's predictive ability. The results indicate both models have reasonable prognostic capability. The LACE index with additional risk factors did little to improve prognostication, while adding to the model's complexity. Findings support the use of the LACE index as a practical tool to identify patients at risk for readmission.

  6. External Validation and Update of a Prediction Rule for the Duration of Sickness Absence Due to Common Mental Disorders

    NARCIS (Netherlands)

    Norder, Giny; Roelen, Corne A. M.; van der Klink, Jac J. L.; Bultmann, Ute; Sluiter, J. K.; Nieuwenhuijsen, K.

    Purpose The objective of the present study was to validate an existing prediction rule (including age, education, depressive/anxiety symptoms, and recovery expectations) for predictions of the duration of sickness absence due to common mental disorders (CMDs) and investigate the added value of

  7. A Study of the Predictive Validity of the Children's Depression Inventory for Major Depression Disorder in Puerto Rican Adolescents

    Science.gov (United States)

    Rivera-Medina, Carmen L.; Bernal, Guillermo; Rossello, Jeannette; Cumba-Aviles, Eduardo

    2010-01-01

    This study aims to evaluate the predictive validity of the Children's Depression Inventory items for major depression disorder (MDD) in an outpatient clinic sample of Puerto Rican adolescents. The sample consisted of 130 adolescents, 13 to 18 years old. The five most frequent symptoms of the Children's Depression Inventory that best predict the…

  8. Validity of biomarkers predicting onset or progression of nephropathy in patients with Type 2 diabetes : a systematic review

    NARCIS (Netherlands)

    Hellemons, M. E.; Kerschbaum, J.; Bakker, S. J. L.; Neuwirt, H.; Mayer, B.; Mayer, G.; de Zeeuw, D.; Lambers Heerspink, H. J.; Rudnicki, M.

    2012-01-01

    Novel biomarkers predicting onset or progression of nephropathy in patients with Type 2 diabetes have been recently identified. We performed a systematic review to assess the validity of biomarkers predicting onset or progression of nephropathy in patients with Type 2 diabetes in longitudinal studie

  9. Prediction models for risk of developing type 2 diabetes : systematic literature search and independent external validation study

    NARCIS (Netherlands)

    Abbasi, Ali; Peelen, Linda M.; Corpeleijn, Eva; van der Schouw, Yvonne T.; Stolk, Ronald P.; Spijkerman, Annemieke M. W.; van der A, Daphne L.; Moons, Karel G. M.; Navis, Gerjan; Bakker, Stephan J. L.; Beulens, Joline W. J.

    2012-01-01

    Objective To identify existing prediction models for the risk of development of type 2 diabetes and to externally validate them in a large independent cohort. Data sources Systematic search of English, German, and Dutch literature in PubMed until February 2011 to identify prediction models for diabe

  10. Aptitude Tests and Successful College Students: The Predictive Validity of the General Aptitude Test (GAT) in Saudi Arabia

    Science.gov (United States)

    Alnahdi, Ghaleb Hamad

    2015-01-01

    Aptitude tests should predict student success at the university level. This study examined the predictive validity of the General Aptitude Test (GAT) in Saudi Arabia. Data for 27420 students enrolled at Prince Sattam bin Abdulaziz University were analyzed. Of these students, 17565 were male students, and 9855 were female students. Multiple…

  11. 'Prediction models for risk of developing type 2 diabetes: systematic literature search and independent external validation study'

    NARCIS (Netherlands)

    Beulens, Joline W J; Abbasi, Ali; Peelen, Linda M; Spijkerman, Annemieke M W; van der A, Daphne L; Corpeleijn, Eva; Bakker, Stephan J L; van der Schouw, Yvonne T

    2013-01-01

    OBJECTIVE: To validate risk scores to predict occurrence of type 2 diabetes in the Dutch population. DESIGN: Prospective cohort study. METHODS: Twelve basic risk scores and 13 extensive risk scores with biomarkers were used to predict the risk of developing type 2 diabetes during 7.5 years in a pros

  12. The validity of predicted body fat percent from body mass index and from impedance in samples of five European populations

    NARCIS (Netherlands)

    Deurenberg, P.; Andreoli, A.; Borg, P.; Kukkonen-Harjula, K.; Lorenzo, de A.; Marken Lichtenbelt, van W.; Testolin, G.; Vigano, R.; Vollaard, N.

    2001-01-01

    Objectives: To test and compare the validity of a body mass index (BMI)-based prediction equation and an impedance-based prediction equation for body fat percentage among various European population groups. Design: Cross-sectional observational study. Settings: The study was performed in five differ

  13. 'Prediction models for risk of developing type 2 diabetes: systematic literature search and independent external validation study'

    NARCIS (Netherlands)

    Beulens, Joline W J; Abbasi, Ali; Peelen, Linda M; Spijkerman, Annemieke M W; van der A, Daphne L; Corpeleijn, Eva; Bakker, Stephan J L; van der Schouw, Yvonne T

    2013-01-01

    OBJECTIVE: To validate risk scores to predict occurrence of type 2 diabetes in the Dutch population. DESIGN: Prospective cohort study. METHODS: Twelve basic risk scores and 13 extensive risk scores with biomarkers were used to predict the risk of developing type 2 diabetes during 7.5 years in a

  14. The development and validation of two prediction models to identify employees at risk of high sickness absence

    NARCIS (Netherlands)

    Roelen, Corne A.; van Rhenen, Willem; Groothoff, Johan W.; van der Klink, Jac J.; Bultmann, Ute; Heymans, Martijn W.

    Background: Sickness absence (SA) is a public health risk marker for morbidity and mortality. The aim of this study was to develop and validate prediction models to identify employees at risk of high SA. Methods: Two prediction models were developed using self-rated health (SRH) and prior SA as

  15. Readmissions and death after ICU discharge: development and validation of two predictive models.

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    Omar Badawi

    Full Text Available INTRODUCTION: Early discharge from the ICU is desirable because it shortens time in the ICU and reduces care costs, but can also increase the likelihood of ICU readmission and post-discharge unanticipated death if patients are discharged before they are stable. We postulated that, using eICU® Research Institute (eRI data from >400 ICUs, we could develop robust models predictive of post-discharge death and readmission that may be incorporated into future clinical information systems (CIS to assist ICU discharge planning. METHODS: Retrospective, multi-center, exploratory cohort study of ICU survivors within the eRI database between 1/1/2007 and 3/31/2011. EXCLUSION CRITERIA: DNR or care limitations at ICU discharge and discharge to location external to hospital. Patients were randomized (2∶1 to development and validation cohorts. Multivariable logistic regression was performed on a broad range of variables including: patient demographics, ICU admission diagnosis, admission severity of illness, laboratory values and physiologic variables present during the last 24 hours of the ICU stay. Multiple imputation was used to address missing data. The primary outcomes were the area under the receiver operator characteristic curves (auROC in the validation cohorts for the models predicting readmission and death within 48 hours of ICU discharge. RESULTS: 469,976 and 234,987 patients representing 219 hospitals were in the development and validation cohorts. Early ICU readmission and death was experienced by 2.54% and 0.92% of all patients, respectively. The relationship between predictors and outcomes (death vs readmission differed, justifying the need for separate models. The models for early readmission and death produced auROCs of 0.71 and 0.92, respectively. Both models calibrated well across risk groups. CONCLUSIONS: Our models for death and readmission after ICU discharge showed good to excellent discrimination and good calibration. Although

  16. Validation and Use of a Predictive Modeling Tool: Employing Scientific Findings to Improve Responsible Conduct of Research Education.

    Science.gov (United States)

    Mulhearn, Tyler J; Watts, Logan L; Todd, E Michelle; Medeiros, Kelsey E; Connelly, Shane; Mumford, Michael D

    2017-01-01

    Although recent evidence suggests ethics education can be effective, the nature of specific training programs, and their effectiveness, varies considerably. Building on a recent path modeling effort, the present study developed and validated a predictive modeling tool for responsible conduct of research education. The predictive modeling tool allows users to enter ratings in relation to a given ethics training program and receive instantaneous evaluative information for course refinement. Validation work suggests the tool's predicted outcomes correlate strongly (r = 0.46) with objective course outcomes. Implications for training program development and refinement are discussed.

  17. The Psychology of Replication and Replication in Psychology.

    Science.gov (United States)

    Francis, Gregory

    2012-11-01

    Like other scientists, psychologists believe experimental replication to be the final arbiter for determining the validity of an empirical finding. Reports in psychology journals often attempt to prove the validity of a hypothesis or theory with multiple experiments that replicate a finding. Unfortunately, these efforts are sometimes misguided because in a field like experimental psychology, ever more successful replication does not necessarily ensure the validity of an empirical finding. When psychological experiments are analyzed with statistics, the rules of probability dictate that random samples should sometimes be selected that do not reject the null hypothesis, even if an effect is real. As a result, it is possible for a set of experiments to have too many successful replications. When there are too many successful replications for a given set of experiments, a skeptical scientist should be suspicious that null or negative findings have been suppressed, the experiments were run improperly, or the experiments were analyzed improperly. This article describes the implications of this observation and demonstrates how to test for too much successful replication by using a set of experiments from a recent research paper.

  18. A psychometric investigation into the cross validation of an adaptation of the Ghiselli Predictability Index in personnel selection

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    Callie Theron

    2006-04-01

    Full Text Available Twigge, Theron, Steele and Meiring (2004 concluded that it is possible to develop a predictability index based on a concept originally proposed by Ghiselli (1956, 1960a, 1960b, which correlates with the real residuals derived from the regression of a criterion on one or more predictors. The addition of such a predictability index to the original regression model was found to produce a statistically significant increase in the correlation between the selection battery and the criterion. To be able to convincingly demonstrate the feasibility of enhancing selection utility through the use of predictability indices would, however, require the cross validation of the results obtained on a derivation sample on a holdout sample selected from the same population. The objective of this article consequently is to investigate the extent to which such a predictability index, developed on a validation sample, would successfully cross validate to a holdout sample. Encouragingly positive results were obtained. Recommendations for future research are made.

  19. Prediction of vibration characteristics in beam structure using sub-scale modeling with experimental validation

    Science.gov (United States)

    Zai, Behzad Ahmed; Sami, Saad; Khan, M. Amir; Ahmad, Furqan; Park, Myung Kyun

    2015-09-01

    Geometric or sub-scale modeling techniques are used for the evaluation of large and complex dynamic structures to ensure accurate reproduction of load path and thus leading to true dynamic characteristics of such structures. The sub-scale modeling technique is very effective in the prediction of vibration characteristics of original large structure when the experimental testing is not feasible due to the absence of a large testing facility. Previous researches were more focused on free and harmonic vibration case with little or no consideration for readily encountered random vibration. A sub-scale modeling technique is proposed for estimating the vibration characteristics of any large scale structure such as Launch vehicles, Mega structures, etc., under various vibration load cases by utilizing precise scaled-down model of that dynamic structure. In order to establish an analytical correlation between the original structure and its scaled models, different scale models of isotropic cantilever beam are selected and analyzed under various vibration conditions( i.e. free, harmonic and random) using finite element package ANSYS. The developed correlations are also validated through experimental testing. The prediction made from the vibratory response of the scaled-down beam through the established sets of correlation are found similar to the response measured from the testing of original beam structure. The established correlations are equally applicable in the prediction of dynamic characteristics of any complex structure through its scaled-down models. This paper presents modified sub-scale modeling technique that enables accurate prediction of vibration characteristics of large and complex structure under not only sinusoidal but also for random vibrations.

  20. Predictive Validity of National Basketball Association Draft Combine on Future Performance.

    Science.gov (United States)

    Teramoto, Masaru; Cross, Chad L; Rieger, Randall H; Maak, Travis G; Willick, Stuart E

    2017-01-20

    The National Basketball Association (NBA) Draft Combine is an annual event where prospective players are evaluated in terms of their athletic abilities and basketball skills. Data collected at the Combine should help NBA teams select right the players for the upcoming NBA Draft, however its value for predicting future performance of players has not been examined. This study investigated predictive validity of the NBA Draft Combine on future performance of basketball players. We performed a principal component analysis (PCA) on the 2010-2015 Combine data to reduce correlated variables (N = 234), a correlation analysis on the Combine data and future on-court performance to examine relationships (maximum pairwise N = 217), and a robust principal component regression (PCR) analysis to predict first-year and three-year on-court performance from the Combine measures (N = 148 and 127, respectively). Three components were identified within the Combine data via PCA (= Combine subscales): length-size, power-quickness, and upper-body strength. Per the correlation analysis, the individual Combine items for anthropometrics, including height without shoes, standing reach, weight, wingspan, and hand length, as well as the Combine subscale of length-size, had positive, medium-to-large sized correlations (r = 0.313-0.545) with defensive performance quantified by Defensive Box Plus/Minus. The robust PCR analysis showed that the Combine subscale of length-size was a predictor most significantly associated with future on-court performance (p NBA Draft Combine has value for predicting future performance of players.

  1. Wearable Lactate Threshold Predicting Device is Valid and Reliable in Runners.

    Science.gov (United States)

    Borges, Nattai R; Driller, Matthew W

    2016-08-01

    Borges, NR and Driller, MW. Wearable lactate threshold predicting device is valid and reliable in runners. J Strength Cond Res 30(8): 2212-2218, 2016-A commercially available device claiming to be the world's first wearable lactate threshold predicting device (WLT), using near-infrared LED technology, has entered the market. The aim of this study was to determine the levels of agreement between the WLT-derived lactate threshold workload and traditional methods of lactate threshold (LT) calculation and the interdevice and intradevice reliability of the WLT. Fourteen (7 male, 7 female; mean ± SD; age: 18-45 years, height: 169 ± 9 cm, mass: 67 ± 13 kg, V[Combining Dot Above]O2max: 53 ± 9 ml·kg·min) subjects ranging from recreationally active to highly trained athletes completed an incremental exercise test to exhaustion on a treadmill. Blood lactate samples were taken at the end of each 3-minute stage during the test to determine lactate threshold using 5 traditional methods from blood lactate analysis which were then compared against the WLT predicted value. In a subset of the population (n = 12), repeat trials were performed to determine both inter-reliability and intrareliability of the WLT device. Intraclass correlation coefficient (ICC) found high to very high agreement between the WLT and traditional methods (ICC > 0.80), with TEMs and mean differences ranging between 3.9-10.2% and 1.3-9.4%. Both interdevice and intradevice reliability resulted in highly reproducible and comparable results (CV 0.97). This study suggests that the WLT is a practical, reliable, and noninvasive tool for use in predicting LT in runners.

  2. Validation of the Lacaine-Huguier predictive score for choledocholithiasis: prospective study of 380 patients.

    Science.gov (United States)

    Khalfallah, M; Dougaz, W; Bedoui, R; Bouasker, I; Chaker, Y; Nouira, R; Dziri, C

    2012-02-01

    The aim of this study was to validate the Lacaine-Huguier score for the prediction of asymptomatic choledocholithiasis. The study enrolled patients over age 18 with symptomatic chronic or acute calculous cholecystitis. Patients already known to have common bile duct stones (CBDS), as evidenced by symptomatic presentation with acute cholangitis or acute gallstone pancreatitis, were not included. We compared the group of patients with a score less than 3.5 versus those with a score greater or equal to 3.5; we also compared the group of patients who underwent intraoperative cholangiography (IOC) with those who did not undergo IOC. The negative predictive value of the Lacaine-Huguier score was calculated. We note that 308 women and 72 men were consecutively enrolled between February 2008 to March 2009; the average age was 51±16.4 years. The score was less than 3.5 in 154 patients (40.5%). IOC was only performed in 135 of the 226 patients with a score greater or equal to 3.5; reasons for this included a very narrow cystic duct in 67 cases, preoperative miscalculation of the score in nine cases, a technical problem in eight cases, an unspecified reason in four cases, contraindication due to pregnancy in two cases, and intraoperative difficulties in one case. CBDS were detected by IOC in 18 cases. Performance of IOC lengthened the median operative time by 20 minutes. The median follow-up was 8 months (range: 0-30 months). Eleven patients were lost to follow-up (2.9%), six of these had a score less than 3.5. Two patients had residual common bile duct (CBD) stones, one of whom had a score less than 3.5. The negative predictive value was 99.4% (95% confidence interval (CI 95%)=[98-100%]). The risk of leaving a stone in the CBD was 0.6%. When data was analyzed according to the worst case scenario, the negative predictive value became 95.5% (CI 95%=[92-99%]) with a risk of residual CBDS of 4.5%. This study confirmed the validity of the Lacaine-Huguier score. When the score is

  3. Development and validation of a clinical prediction rule for chest wall syndrome in primary care

    Directory of Open Access Journals (Sweden)

    Ronga Alexandre

    2012-08-01

    Full Text Available Abstract Background Chest wall syndrome (CWS, the main cause of chest pain in primary care practice, is most often an exclusion diagnosis. We developed and evaluated a clinical prediction rule for CWS. Methods Data from a multicenter clinical cohort of consecutive primary care patients with chest pain were used (59 general practitioners, 672 patients. A final diagnosis was determined after 12 months of follow-up. We used the literature and bivariate analyses to identify candidate predictors, and multivariate logistic regression was used to develop a clinical prediction rule for CWS. We used data from a German cohort (n = 1212 for external validation. Results From bivariate analyses, we identified six variables characterizing CWS: thoracic pain (neither retrosternal nor oppressive, stabbing, well localized pain, no history of coronary heart disease, absence of general practitioner’s concern, and pain reproducible by palpation. This last variable accounted for 2 points in the clinical prediction rule, the others for 1 point each; the total score ranged from 0 to 7 points. The area under the receiver operating characteristic (ROC curve was 0.80 (95% confidence interval 0.76-0.83 in the derivation cohort (specificity: 89%; sensitivity: 45%; cut-off set at 6 points. Among all patients presenting CWS (n = 284, 71% (n = 201 had a pain reproducible by palpation and 45% (n = 127 were correctly diagnosed. For a subset (n = 43 of these correctly classified CWS patients, 65 additional investigations (30 electrocardiograms, 16 thoracic radiographies, 10 laboratory tests, eight specialist referrals, one thoracic computed tomography had been performed to achieve diagnosis. False positives (n = 41 included three patients with stable angina (1.8% of all positives. External validation revealed the ROC curve to be 0.76 (95% confidence interval 0.73-0.79 with a sensitivity of 22% and a specificity of 93%. Conclusions This CWS score offers

  4. Summary of best guidelines and validation of CFD modeling in livestock buildings to ensure prediction quality

    DEFF Research Database (Denmark)

    Rong, Li; Nielsen, Peter V.; Bjerg, Bjarne

    2016-01-01

    scale pig barns was simulated to show the procedures of validating a CFD simulation in livestock buildings. After summarizing the guideline and/or best practice for CFD modeling, the authors addressed the issues related to numerical methods and the governing equations, which were limited to RANS models....... Although it is not necessary to maintain the same format of reporting the CFD modeling as presented in this paper, the authors would suggest including all the information related to the selection of turbulence models, difference schemes, convergence criteria, boundary conditions, geometry simplification......Computational Fluid Dynamics (CFD) is increasingly used to study airflow around and in livestock buildings, to develop technologies to mitigate emissions and to predict the contaminant dispersion from livestock buildings. In this paper, an example of air flow distribution in a room with two full...

  5. Prediction and validation of concentration gradient generation in a paper-based microfluidic channel

    Science.gov (United States)

    Jang, Ilhoon; Kim, Gang-June; Song, Simon

    2016-11-01

    A paper-based microfluidic channel has obtained attention as a diagnosis device that can implement various chemical or biological reactions. With benefits of thin, flexible, and strong features of paper devices, for example, it is often utilized for cell culture where controlling oxygen, nutrients, metabolism, and signaling molecules gradient affects the growth and movement of the cells. Among various features of paper-based microfluidic devices, we focus on establishment of concentration gradient in a paper channel. The flow is subject to dispersion and capillary effects because a paper is a porous media. In this presentation, we describe facile, fast and accurate method of generating a concentration gradient by using flow mixing of different concentrations. Both theoretical prediction and experimental validation are discussed along with inter-diffusion characteristics of porous flows. This work was supported by the National Research Foundation of Korea(NRF) Grant funded by the Korea government(MSIP) (No. 2016R1A2B3009541).

  6. Cardiorespiratory fitness of asthmatic children and validation of predicted aerobic capacity

    DEFF Research Database (Denmark)

    Lochte, Lene; Angermann, Marie; Larsson, Benny

    2009-01-01

    INTRODUCTION: Predicted aerobic capacity (PAC) was estimated by submaximal exercise test and compared with monitored aerobic capacity (MAC) measured by laboratory conditions [maximal oxygen uptake (VO(2peak))] in 18 children and adolescents, 10 asthmatics and 8 matched controls. Objectives......: To compare aerobic capacity between asthmatic children and controls, to estimate the agreement between PAC and MAC and observe for trend of PAC. MATERIALS AND METHODS: The design was prospective, 4 years (PAC) and cross-sectional (MAC and VO(2peak)). Non-parametric Wilcoxon rank sums were applied......). Physical activity level and subjective health showed no differences between groups, or level and categories, respectively. CONCLUSION: The asthmatic participants presented with lower aerobic capacity than controls in both PAC and MAC; therefore, results confirmed the validity of the PAC method. Data...

  7. Phencyclidine in the social interaction test: an animal model of schizophrenia with face and predictive validity.

    Science.gov (United States)

    Sams-Dodd, F

    1999-01-01

    Phencyclidine (PCP) is a hallucinogenic drug that can mimic several aspects of the schizophrenic symptomatology in healthy volunteers. In a series of studies PCP was administered to rats to determine whether it was possible to develop an animal model of the positive and negative symptoms of schizophrenia. The rats were tested in the social interaction test and it was found that PCP dose-dependently induces stereotyped behaviour and social withdrawal, which may correspond to certain aspects of the positive and negative symptoms, respectively. The effects of PCP could be reduced selectively by antipsychotic drug treatment, whereas drugs lacking antipsychotic effects did not alleviate the PCP-induced behaviours. Together these findings indicate that PCP effects in the rat social interaction test may be a model of the positive and negative symptoms of schizophrenia with face and predictive validity and that it may be useful for the evaluation of novel antipsychotic compounds.

  8. The Predictive Validity of using Admissions Testing and Multiple Mini-interviews in Undergraduate University Admissions

    DEFF Research Database (Denmark)

    Makransky, Guido; Havmose, Philip S.; Vang, Maria

    2016-01-01

    The aim of this study was to evaluate the predictive validity of a two-step admissions procedure that included a cognitive ability test followed by multiple mini-interviews (MMI) used to assess non-cognitive skills compared to a grade-based admissions relative to subsequent drop-out rates...... and academic achievement after one and two years of study. The participants consisted of the entire population of 422 psychology students who were admitted to the University of Southern Denmark between 2010 and 2013. The results showed significantly lower drop-out rates after the first year of study, and non......-significant lower drop-out rates after the second year of study for the admission procedure that included the assessment of non-cognitive skills though the MMI. Furthermore, this admission procedure resulted in a significant lower risk of failing the final exam after the first and second year of study, compared...

  9. Gene Expression-Based Survival Prediction in Lung Adenocarcinoma: A Multi-Site, Blinded Validation Study

    Science.gov (United States)

    Shedden, Kerby; Taylor, Jeremy M.G.; Enkemann, Steve A.; Tsao, Ming S.; Yeatman, Timothy J.; Gerald, William L.; Eschrich, Steve; Jurisica, Igor; Venkatraman, Seshan E.; Meyerson, Matthew; Kuick, Rork; Dobbin, Kevin K.; Lively, Tracy; Jacobson, James W.; Beer, David G.; Giordano, Thomas J.; Misek, David E.; Chang, Andrew C.; Zhu, Chang Qi; Strumpf, Dan; Hanash, Samir; Shepherd, Francis A.; Ding, Kuyue; Seymour, Lesley; Naoki, Katsuhiko; Pennell, Nathan; Weir, Barbara; Verhaak, Roel; Ladd-Acosta, Christine; Golub, Todd; Gruidl, Mike; Szoke, Janos; Zakowski, Maureen; Rusch, Valerie; Kris, Mark; Viale, Agnes; Motoi, Noriko; Travis, William; Sharma, Anupama

    2009-01-01

    Although prognostic gene expression signatures for survival in early stage lung cancer have been proposed, for clinical application it is critical to establish their performance across different subject populations and in different laboratories. Here we report a large, training-testing, multi-site blinded validation study to characterize the performance of several prognostic models based on gene expression for 442 lung adenocarcinomas. The hypotheses proposed examined whether microarray measurements of gene expression either alone or combined with basic clinical covariates (stage, age, sex) can be used to predict overall survival in lung cancer subjects. Several models examined produced risk scores that substantially correlated with actual subject outcome. Most methods performed better with clinical data, supporting the combined use of clinical and molecular information when building prognostic models for early stage lung cancer. This study also provides the largest available set of microarray data with extensive pathological and clinical annotation for lung adenocarcinomas. PMID:18641660

  10. Prediction models for the mortality risk in chronic dialysis patients: a systematic review and independent external validation study.

    Science.gov (United States)

    Ramspek, Chava L; Voskamp, Pauline Wm; van Ittersum, Frans J; Krediet, Raymond T; Dekker, Friedo W; van Diepen, Merel

    2017-01-01

    In medicine, many more prediction models have been developed than are implemented or used in clinical practice. These models cannot be recommended for clinical use before external validity is established. Though various models to predict mortality in dialysis patients have been published, very few have been validated and none are used in routine clinical practice. The aim of the current study was to identify existing models for predicting mortality in dialysis patients through a review and subsequently to externally validate these models in the same large independent patient cohort, in order to assess and compare their predictive capacities. A systematic review was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. To account for missing data, multiple imputation was performed. The original prediction formulae were extracted from selected studies. The probability of death per model was calculated for each individual within the Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD). The predictive performance of the models was assessed based on their discrimination and calibration. In total, 16 articles were included in the systematic review. External validation was performed in 1,943 dialysis patients from NECOSAD for a total of seven models. The models performed moderately to well in terms of discrimination, with C-statistics ranging from 0.710 (interquartile range 0.708-0.711) to 0.752 (interquartile range 0.750-0.753) for a time frame of 1 year. According to the calibration, most models overestimated the probability of death. Overall, the performance of the models was poorer in the external validation than in the original population, affirming the importance of external validation. Floege et al's models showed the highest predictive performance. The present study is a step forward in the use of a prediction model as a useful tool for nephrologists, using evidence-based medicine that

  11. Development and Validation of Predictive Models of Cardiac Mortality and Transplantation in Resynchronization Therapy

    Directory of Open Access Journals (Sweden)

    Eduardo Arrais Rocha

    2015-01-01

    Full Text Available Abstract Background: 30-40% of cardiac resynchronization therapy cases do not achieve favorable outcomes. Objective: This study aimed to develop predictive models for the combined endpoint of cardiac death and transplantation (Tx at different stages of cardiac resynchronization therapy (CRT. Methods: Prospective observational study of 116 patients aged 64.8 ± 11.1 years, 68.1% of whom had functional class (FC III and 31.9% had ambulatory class IV. Clinical, electrocardiographic and echocardiographic variables were assessed by using Cox regression and Kaplan-Meier curves. Results: The cardiac mortality/Tx rate was 16.3% during the follow-up period of 34.0 ± 17.9 months. Prior to implantation, right ventricular dysfunction (RVD, ejection fraction < 25% and use of high doses of diuretics (HDD increased the risk of cardiac death and Tx by 3.9-, 4.8-, and 5.9-fold, respectively. In the first year after CRT, RVD, HDD and hospitalization due to congestive heart failure increased the risk of death at hazard ratios of 3.5, 5.3, and 12.5, respectively. In the second year after CRT, RVD and FC III/IV were significant risk factors of mortality in the multivariate Cox model. The accuracy rates of the models were 84.6% at preimplantation, 93% in the first year after CRT, and 90.5% in the second year after CRT. The models were validated by bootstrapping. Conclusion: We developed predictive models of cardiac death and Tx at different stages of CRT based on the analysis of simple and easily obtainable clinical and echocardiographic variables. The models showed good accuracy and adjustment, were validated internally, and are useful in the selection, monitoring and counseling of patients indicated for CRT.

  12. External Validation of the PECARN Head Trauma Prediction Rules in Japan.

    Science.gov (United States)

    Ide, Kentaro; Uematsu, Satoko; Tetsuhara, Kenichi; Yoshimura, Satoshi; Kato, Takahiro; Kobayashi, Tohru

    2017-03-01

    The Pediatric Emergency Care Applied Research Network (PECARN) head trauma prediction rules are used to assist computed tomography (CT) decision-making for children with minor head trauma. Although the PECARN rules have been validated in North America and Europe, they have not yet been validated in Asia. In Japan, there are no clinical decision rules for children with minor head trauma. The rate of head CT for children with minor head trauma in Japan is high since CT is widely accessible across the country. The objective of this study was to evaluate the diagnostic accuracy of the PECARN rules for identifying clinically important traumatic brain injuries (ciTBI) in children with minor head trauma in Japan. We conducted a retrospective cohort study at a tertiary care pediatric hospital in Japan (30,000 patients/year). We enrolled all children younger than 18 years with minor head trauma (Glasgow Coma Scale ≥ 14) who presented to the emergency department within 24 hours of their injury between January and December 2013. We retrospectively classified the children into three risk categories according to the PECARN rules. The PECARN rules were considered negative when children were classified into the very-low-risk category. The primary outcome was considered positive when a child had ciTBI defined as head injury resulting in death, neurosurgery, intubation for > 24 hours, or hospital admission ≥ 2 nights with evidence of TBI on CT. Among 2,208 children included in the study, 24 (1.1%) had ciTBI. Sensitivities and specificities of the PECARN rules to predict ciTBI were 85.7% (12/14; 95% confidence interval [CI] = 57.2 to 98.2) and 73.5% (572/778; 95% CI = 70.3 to 76.6), respectively, for children Japan. © 2016 by the Society for Academic Emergency Medicine.

  13. Predicting Behavior Assessment System for Children-Second Edition Self-Report of Personality Child Form Results Using the Behavioral and Emotional Screening System Student Form: A Replication Study with an Urban, Predominantly Latino/a Sample

    Science.gov (United States)

    Kiperman, Sarah; Black, Mary S.; McGill, Tia M.; Harrell-Williams, Leigh M.; Kamphaus, Randy W.

    2014-01-01

    This study assesses the ability of a brief screening form, the Behavioral and Emotional Screening System-Student Form (BESS-SF), to predict scores on the much longer form from which it was derived: the Behavior Assessment System for Children-Second Edition Self-Report of Personality-Child Form (BASC-2-SRP-C). The present study replicates a former…

  14. Construct and predictive validity of a self-reported measure of preclinical mobility limitation.

    Science.gov (United States)

    Mänty, Minna; Heinonen, Ari; Leinonen, Raija; Törmäkangas, Timo; Sakari-Rantala, Ritva; Hirvensalo, Mirja; von Bonsdorff, Mikaela B; Rantanen, Taina

    2007-09-01

    To validate self-reported preclinical mobility limitation concept and self-report assessment method against muscle power and walking speed, and to study the predictive validity of preclinical mobility limitation with respect to future risk of manifest mobility limitation. Observational prospective cohort study and cross-sectional analysis. Research laboratory and community. A total of 632 community-living (age range, 75-81 y) women and men took part in the baseline assessments and 302 persons in the semi-annual interviews on mobility limitation over 2 years. Not applicable. Walking speed, muscle power, and self-reported preclinical and manifest mobility limitation. Preclinical mobility limitation was defined as self-reported tiredness or modification of task performance without task difficulty. At baseline, 4 subgroups were created according to self-reported preclinical mobility limitation in any of 3 mobility tasks (walking 2 km, walking 0.5 km, climbing up stairs): no limitation, preclinical limitation, and minor and major manifest limitation. At baseline, participants with preclinical mobility limitation showed intermediate levels of walking speed and muscle power, compared with those with no limitation or manifest mobility limitation. Participants reporting baseline preclinical mobility limitation had 3- to 6-fold higher age- and sex-adjusted risk of progressing to major manifest mobility limitation during the 2-year follow-up compared with participants with no limitation at baseline, whereas the risk among those with minor limitation at baseline was 14- to 18-fold higher compared with those with no limitation. The self-report assessment tool proved to be a valid measure to capture the early signs of disability and may serve as an inexpensive tool for identifying those nondisabled persons at high risk for future disability.

  15. Positive predictive value of cardiovascular diagnoses in the Danish National Patient Registry: a validation study

    Science.gov (United States)

    Sundbøll, Jens; Adelborg, Kasper; Munch, Troels; Frøslev, Trine; Sørensen, Henrik Toft; Bøtker, Hans Erik; Schmidt, Morten

    2016-01-01

    Objective The majority of cardiovascular diagnoses in the Danish National Patient Registry (DNPR) remain to be validated despite extensive use in epidemiological research. We therefore examined the positive predictive value (PPV) of cardiovascular diagnoses in the DNPR. Design Population-based validation study. Setting 1 university hospital and 2 regional hospitals in the Central Denmark Region, 2010–2012. Participants For each cardiovascular diagnosis, up to 100 patients from participating hospitals were randomly sampled during the study period using the DNPR. Main outcome measure Using medical record review as the reference standard, we examined the PPV for cardiovascular diagnoses in the DNPR, coded according to the International Classification of Diseases, 10th Revision. Results A total of 2153 medical records (97% of the total sample) were available for review. The PPVs ranged from 64% to 100%, with a mean PPV of 88%. The PPVs were ≥90% for first-time myocardial infarction, stent thrombosis, stable angina pectoris, hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, takotsubo cardiomyopathy, arterial hypertension, atrial fibrillation or flutter, cardiac arrest, mitral valve regurgitation or stenosis, aortic valve regurgitation or stenosis, pericarditis, hypercholesterolaemia, aortic dissection, aortic aneurysm/dilation and arterial claudication. The PPVs were between 80% and 90% for recurrent myocardial infarction, first-time unstable angina pectoris, pulmonary hypertension, bradycardia, ventricular tachycardia/fibrillation, endocarditis, cardiac tumours, first-time venous thromboembolism and between 70% and 80% for first-time and recurrent admission due to heart failure, first-time dilated cardiomyopathy, restrictive cardiomyopathy and recurrent venous thromboembolism. The PPV for first-time myocarditis was 64%. The PPVs were consistent within age, sex, calendar year and hospital categories. Conclusions The validity of

  16. Validation of MATRA-S Low Flow Predictions Using PNL 2x6 Mixed Convection Test

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Kyong-Won; Kwon, Hyuk; Kim, Seong-Jin; Hwang, Dae-Hyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The MATRA-S, a subchannel analysis code has been used to thermal-hydraulic design of SMART core. As the safety enhancement is getting important more and more, some features of the MATRA-S code are required to be validated in order to be applied to nonnominal operating conditions in addition to its applicability to reactor design under normal operating conditions. The MATRA-S code has two numerical schemes, SCHEME for implicit application and XSCHEM for explicit one. The implicit scheme had been developed under assumptions that the axial flow is larger enough than the crossflow. Under certain conditions, especially low flow and low pressure operating conditions, this implicit SCHEME oscillates or becomes unstable numerically and then MATRA-S fails to obtain good solution. These demerits were known as common in implicit schemes of many COBRA families. Efforts have been exerted to resolve these limitations in SCHEME of the MATRA-S such as a once through marching scheme against the multi-pass marching scheme and an adaptive multi-grid method. These remedies can reduce the numerically unstable range for SCHEME but some unstable regions still remain. The XSCHEM, an explicit scheme of MATRA-S was validated using the PNL 2x6 rod bundle flow transient test. The explicit scheme agreed with implicit scheme for steady state calculations. And it showed its capability to predict low flow conditions such as negative flow and recirculation flow.

  17. Predictive Model for Particle Residence Time Distributions in Riser Reactors. Part 1: Model Development and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Foust, Thomas D.; Ziegler, Jack L.; Pannala, Sreekanth; Ciesielski, Peter; Nimlos, Mark R.; Robichaud, David J.

    2017-01-16

    In this computational study, we model the mixing of biomass pyrolysis vapor with solid catalyst in circulating riser reactors with a focus on the determination of solid catalyst residence time distributions (RTDs). A comprehensive set of 2D and 3D simulations were conducted for a pilot-scale riser using the Eulerian-Eulerian two-fluid modeling framework with and without sub-grid-scale models for the gas-solids interaction. A validation test case was also simulated and compared to experiments, showing agreement in the pressure gradient and RTD mean and spread. For simulation cases, it was found that for accurate RTD prediction, the Johnson and Jackson partial slip solids boundary condition was required for all models and a sub-grid model is useful so that ultra high resolutions grids that are very computationally intensive are not required. We discovered a 2/3 scaling relation for the RTD mean and spread when comparing resolved 2D simulations to validated unresolved 3D sub-grid-scale model simulations.

  18. Concurrent and predictive validity of the Substance Dependence Severity Scale (SDSS).

    Science.gov (United States)

    Miele, G M; Carpenter, K M; Smith Cockerham, M; Dietz Trautman, K; Blaine, J; Hasin, D S

    2000-04-01

    This study investigated the concurrent and predictive validity of the Substance Dependence Severity Scale (SDSS), a clinician-administered interview designed to assess the severity and frequency of DSM-IV dependence symptoms for a range of substances. A total of 172 (107 males and 66 females) treated substance users participated in the study. Of those, 89% (n=153) received at least one follow-up interview within 1-6 months of an initial assessment. For alcohol, cocaine and heroin, convergent and discriminant validity was supported by significant relationships between SDSS scores at baseline and other baseline measures of substance use consequences, such as the Addiction Severity Index (ASI), as well as significant relationships between SDSS change scores from baseline to follow-up and change scores of other measures of consequences. SDSS scores were significantly associated with time to first post treatment use of alcohol, cocaine and heroin, although the nature of the associations was complex. Scale applications and areas for further study are discussed.

  19. New tools and new ideas for HR practitioners. Structural and predictive validity of weighted satisfaction questionnaire

    Directory of Open Access Journals (Sweden)

    Lorenzo Revuelto Taboada

    2012-12-01

    Full Text Available One of the fundamental tasks for an Human Resource Management (HRM practitioner consists in designing a reward system that can be broadly understood and can influence the attitudes and, subsequently, the behavior of individuals to permit achievement of organizational objectives. To do so, appropriate tools are necessary to allow key actions to be identified in terms of motivating employees; thereby, avoiding opportunistic costs derived from allocating resources needed to close the gap in employee satisfaction, with regard to non-priority factors for workers in satisfying their own personal needs. This article, thus, presents a dual assessment scale consisting of 44 items, categorized into six dimensions, which firstly evaluates the importance of motivation and, secondly, the level of satisfaction with the current situation for each of the 44 factors considered. Using a sample of 801 individuals, we analyzedthe internal consistency, face validity, and predictive validity of the measuring scales, obtaining a series of results that were, to say the least, promising

  20. Study on the micro-replication of shark skin

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Direct replication of creatural scarfskins to form biomimetic surfaces with relatively vivid morphology is a new attempt of the bio-replicated forming technology at animal body. Taking shark skins as the replication templates, and the micro-embossing and micro-molding as the material forming methods, the micro-replicating technology of the outward morphology on shark skins was demonstrated. The preliminary analysis on replication precision indicates that the bio-replicated forming technology can replicate the outward morphology of the shark scales with good precision, which validates the application of the bio-replicated forming technology in the direct morphology replication of the firm creatural scarfskins.

  1. Validation of modified Mallampati test with addition of thyromental distance and sternomental distance to predict difficult endotracheal intubation in adults

    Directory of Open Access Journals (Sweden)

    Bhavdip Patel

    2014-01-01

    Full Text Available Background and Aims: Intubation is often a challenge for anaesthesiologists. Many parameters assist to predict difficult intubation. The present study was undertaken to assess the validity of different parameters in predicting difficult intubation for general anaesthesia (GA in adults and effect of combining the parameters on the validity. Methods: The anaesthesiologist assessed oropharynx of 135 adult patients. Modified Mallampati test (MMT was used and the thyromental distance (TMD and sternomental distances (SMD for each of the patients were also measured. The Cormack and Lehane laryngoscopic grading was assessed following laryngoscopy. The validity parameters such as sensitivity, specificity, false positive and negatives values, positive and negative predictive values were calculated. The effect of combining different measurements on the validity was also studied. Univariate analysis was performed using the parametric method. Results: The study group comprised of 135 patients. The sensitivity and specificity of MMT were 28.6% and 93%, respectively. The TMD (<6.5 CM had sensitivity and specificity of 100% and 75.8%, respectively. The SMD (<12.5 CM had sensitivity and specificity of 91% and 92.7%, respectively. Combination of MMT grading and TMD and SMD measurements increased the validity (sensitivity of 100% and specificity of 92.7%. Conclusion: MMT had high specificity. The validity of combination of MMT, SMD and TMD as compared to MMT alone was very high in predicting difficult intubation in adult patients. All parameters should be used in assessing an adult patient for surgery under GA.

  2. Validity of the SAT® for Predicting First-Year Grades: 2012 SAT Validity Sample. Statistical Report 2015 2

    Science.gov (United States)

    Beard, Jonathan; Marini, Jessica P.

    2015-01-01

    The continued accumulation of validity evidence for the intended uses of educational assessment scores is critical to ensure that inferences made using the scores are sound. To that end, the College Board has continued to collect college outcome data to evaluate the relationship between SAT® scores and college success. This report provides updated…

  3. Validity of the SAT® for Predicting First-Year Grades: 2011 SAT Validity Sample. Statistical Report 2013-3

    Science.gov (United States)

    Patterson, Brian F.; Mattern, Krista D.

    2013-01-01

    The continued accumulation of validity evidence for the intended uses of educational assessments is critical to ensure that proper inferences will be made for those purposes. To that end, the College Board has continued to collect college outcome data to evaluate the relationship between SAT® scores and college success. This report provides…

  4. Computational Prediction and Validation of BAHD1 as a Novel Molecule for Ulcerative Colitis

    Science.gov (United States)

    Zhu, Huatuo; Wan, Xingyong; Li, Jing; Han, Lu; Bo, Xiaochen; Chen, Wenguo; Lu, Chao; Shen, Zhe; Xu, Chenfu; Chen, Lihua; Yu, Chaohui; Xu, Guoqiang

    2015-07-01

    Ulcerative colitis (UC) is a common inflammatory bowel disease (IBD) producing intestinal inflammation and tissue damage. The precise aetiology of UC remains unknown. In this study, we applied a rank-based expression profile comparative algorithm, gene set enrichment analysis (GSEA), to evaluate the expression profiles of UC patients and small interfering RNA (siRNA)-perturbed cells to predict proteins that might be essential in UC from publicly available expression profiles. We used quantitative PCR (qPCR) to characterize the expression levels of those genes predicted to be the most important for UC in dextran sodium sulphate (DSS)-induced colitic mice. We found that bromo-adjacent homology domain (BAHD1), a novel heterochromatinization factor in vertebrates, was the most downregulated gene. We further validated a potential role of BAHD1 as a regulatory factor for inflammation through the TNF signalling pathway in vitro. Our findings indicate that computational approaches leveraging public gene expression data can be used to infer potential genes or proteins for diseases, and BAHD1 might act as an indispensable factor in regulating the cellular inflammatory response in UC.

  5. In vivo validation of a computationally predicted conserved Ath5 target gene set.

    Directory of Open Access Journals (Sweden)

    Filippo Del Bene

    2007-09-01

    Full Text Available So far, the computational identification of transcription factor binding sites is hampered by the complexity of vertebrate genomes. Here we present an in silico procedure to predict target sites of a transcription factor in complex genomes using its binding site. In a first step sequence, comparison of closely related genomes identifies the binding sites in conserved cis-regulatory regions (phylogenetic footprinting. Subsequently, more remote genomes are introduced into the comparison to identify highly conserved and therefore putatively functional binding sites (phylogenetic filtering. When applied to the binding site of atonal homolog 5 (Ath5 or ATOH7, this procedure efficiently filters evolutionarily conserved binding sites out of more than 300,000 instances in a vertebrate genome. We validate a selection of the linked target genes by showing coexpression with and transcriptional regulation by Ath5. Finally, chromatin immunoprecipitation demonstrates the occupancy of the target gene promoters by Ath5. Thus, our procedure, applied to whole genomes, is a fast and predictive tool to in silico filter the target genes of a given transcription factor with defined binding site.

  6. Facial soft tissue esthetic predictions: validation in craniomaxillofacial surgery with cone beam computed tomography data.

    Science.gov (United States)

    Bianchi, Alberto; Muyldermans, Louis; Di Martino, Mirko; Lancellotti, Lorenzo; Amadori, Sara; Sarti, Alessandro; Marchetti, Claudio

    2010-07-01

    Facial soft tissue prediction in orthognathic surgery could be a valuable aid to preview the results and determine the best surgical treatment. After many years, considerable difficulties are still present in the prediction of the clinical final aspect. The object of the present study was to validate new soft tissue simulation software (SurgiCase CMF; Materialise, Leuven, Belgium), using data acquired by cone beam computed tomography (CBCT), that makes it possible to foresee the final result. Ten patients with craniomaxillofacial deformations underwent CBCT before surgery. Using the SurgiCase CMF software, the data were reconstructed in 3 dimensions, and various osteotomies were simulated in a 3-dimensional virtual environment by applying different surgical procedures. At 6 months after surgery, the patients underwent repeat CBCT. Thus, it was possible to superimpose the pre- and postoperative CBCT studies to evaluate the reproducibility and reliability of the software. CBCT simulations defined an average absolute error of 0.94 mm, a standard deviation of 0.90 mm, and a percentage of error less than 2 mm of 86.80%. The preliminary results have allowed us to conclude that simulations in orthognathic surgery for skull-maxillofacial deformities using CBCT acquisition are reliable, in addition to the low radiation exposure, and could become the reference standard to plan surgical treatment. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Predictive validity of variables used to select students for postgraduate management courses.

    Science.gov (United States)

    Lane, John; Lane, Andrew M

    2002-06-01

    The present study set in the United Kingdom examined the predictive validity of variables used to select graduate students into postgraduate management programs at a UK business school. 303 postgraduate students completed a cognitive ability test (MD5, Mental Ability Test), a questionnaire to assess perceptions of self-efficacy to succeed on the program, and reported their performance on their first (undergraduate) degree. Students completed these measures at the start of the programs. Each program comprised 12 modules, which all students were required to complete successfully. Students' performance was measured by the average grade obtained over the 12 modules. Multiple regression indicated that only 22% of the variance (Adjusted R2 = .22, p<.001) in students' performance was predicted significantly by cognitive ability scores. Results show that neither performance on first degree nor scores for self-efficacy showed a significant relationship to the criterion measure. Findings from the present study suggest that in the UK, the use of cognitive ability tests may play a significant role in the selection of students into postgraduate programs. Nonsignificant self-efficacy and performance relationships are ascribed to unclear knowledge of the demands of the program. We suggest that there is need for further research to examine factors related to performance.

  8. An extension of the validation of SCALE (SAS2H) isotopic predictions for PWR spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    DeHart, M.D.; Hermann, O.W.

    1996-09-01

    Isotopic characterization of spent fuel via depletion and decay calculations is necessary for determination of source terms. Unlike fresh fuel assumptions typically used in criticality safety analysis of spent fuel configurations, burnup credit applications also rely on depletion and decay calculations to predict spent fuel composition; these isotopics are used in subsequent criticality calculations to assess the reduced worth of spent fuel. To validate the depletion codes and data, experiment is compared with predictions; such comparisons have been done in earlier ORNL work. This report describes additional independent measurements and corresponding calculations as a supplement. The current work includes measured isotopic data from 19 spent fuel samples from the Italian Trino Vercelles PWR and the US Turkey Point-3 PWR. In addition, an approach to determine biases and uncertainties between calculated and measured isotopic concentrations is discussed, together with a method to statistically combine these terms to obtain a conservative estimate of spent fuel isotopic concentrations. Results on combination of measured-to-calculated ratios are presented. The results described herein represent an extension to a new reactor design and spent fuel samples with enrichment as high as 3.9 wt% {sup 235}U. Consistency with the earlier work for each of two different cross-section libraries suggests that the estimated biases for each of the isotopes in the earlier work are reasonably good estimates.

  9. Development and validation of a vitamin D status prediction model in Danish pregnant women

    DEFF Research Database (Denmark)

    Jensen, Camilla; Thorne-Lyman, Andrew; Hansen, Linda

    2013-01-01

    and supplements, outdoor physical activity, tanning bed use, smoking, and month of blood draw explained 40.1% of the variance in 25(OH)D and mean measured 25(OH)D-level increased linearly by decile of predicted 25(OH)D-score. In total 32.2% of the women were placed in the same quintile by both measured......Vitamin D has been hypothesized to reduce risk of pregnancy complications such as preeclampsia, gestational diabetes mellitus, and preterm delivery. However, many of these outcomes are rare and require a large sample size to study, representing a challenge for cohorts with a limited number...... of preserved samples. The aims of this study were to (1) identify predictors of serum 25-hydroxy-vitamin D (25(OH)D) among pregnant women in a subsample (N = 1494) of the Danish National Birth Cohort (DNBC) and (2) develop and validate a score predicting 25(OH)D-status in order to explore associations between...

  10. Prediction models for intracranial hemorrhage or major bleeding in patients on antiplatelet therapy: a systematic review and external validation study.

    Science.gov (United States)

    Hilkens, N A; Algra, A; Greving, J P

    2016-01-01

    ESSENTIALS: Prediction models may help to identify patients at high risk of bleeding on antiplatelet therapy. We identified existing prediction models for bleeding and validated them in patients with cerebral ischemia. Five prediction models were identified, all of which had some methodological shortcomings. Performance in patients with cerebral ischemia was poor. Background Antiplatelet therapy is widely used in secondary prevention after a transient ischemic attack (TIA) or ischemic stroke. Bleeding is the main adverse effect of antiplatelet therapy and is potentially life threatening. Identification of patients at increased risk of bleeding may help target antiplatelet therapy. This study sought to identify existing prediction models for intracranial hemorrhage or major bleeding in patients on antiplatelet therapy and evaluate their performance in patients with cerebral ischemia. We systematically searched PubMed and Embase for existing prediction models up to December 2014. The methodological quality of the included studies was assessed with the CHARMS checklist. Prediction models were externally validated in the European Stroke Prevention Study 2, comprising 6602 patients with a TIA or ischemic stroke. We assessed discrimination and calibration of included prediction models. Five prediction models were identified, of which two were developed in patients with previous cerebral ischemia. Three studies assessed major bleeding, one studied intracerebral hemorrhage and one gastrointestinal bleeding. None of the studies met all criteria of good quality. External validation showed poor discriminative performance, with c-statistics ranging from 0.53 to 0.64 and poor calibration. A limited number of prediction models is available that predict intracranial hemorrhage or major bleeding in patients on antiplatelet therapy. The methodological quality of the models varied, but was generally low. Predictive performance in patients with cerebral ischemia was poor. In order to

  11. A validation of an operational wave and surge prediction system for the Dutch Coast

    Directory of Open Access Journals (Sweden)

    L. Sembiring

    2014-05-01

    Full Text Available Knowledge of the actual condition of hydrodynamics in the nearshore and coastal area is essential for coastal monitoring activities. To this end, a coastal operational model system can serve as a tool in providing recent and up-to-date state of the hydrodynamics along the coast. In this paper we apply CoSMoS (Coastal Storm Modeling System, a generic operational model system applied here to predict storm impact on dunes along the Dutch Coast. The CoSMoS application is not limited to storm impact prediction on the Dutch coast, but can also be applied to other coastal hazards such as rip currents and coastal flooding, in other environments. In this paper, we present the set-up of the CoSMoS system and validation of the wave and surge model within it using deep water wave buoy data and tidal gauge measurements as ground truth validation material. The evaluation is presented as monthly error measures between computed parameters and observed ones. Hindcast results over the whole year of 2009 show that the simulated wave parameters and surge elevation from the CoSMoS are in good agreement with data, with average root mean square error over the year of 0.14 m for the surge elevation and 0.24 m for the significant wave height. It is noted that there is a tendency of the wave model to underestimate the height of northerly waves with lower frequencies (swell. Additionally, when a wave separation algorithm is applied on the overall spectrum, results show consistent underestimation of the swell component by the model, which for the Dutch Coast, will mainly come from the North where the North Sea is open to the Atlantic Ocean. In the proposed model system, the swell boundary can have a significant effect on the simulated wave results, suggesting room for improvement for the swell boundary conditions on the North and the swell propagation within the Dutch Continental Shelf Model. Finally we show that in forecast mode, CoSMoS can provide reasonably good wave

  12. Life Origination Hydrate Theory (LOH-Theory) and Mitosis and Replication Hydrate Theory (MRH-Theory): three-dimensional PC validation

    Science.gov (United States)

    Kadyshevich, E. A.; Dzyabchenko, A. V.; Ostrovskii, V. E.

    2014-04-01

    Size compatibility of the CH4-hydrate structure II and multi-component DNA fragments is confirmed by three-dimensional simulation; it is validation of the Life Origination Hydrate Theory (LOH-Theory).

  13. Predicting plant invasions under climate change: are species distribution models validated by field trials?

    Science.gov (United States)

    Sheppard, Christine S; Burns, Bruce R; Stanley, Margaret C

    2014-09-01

    Climate change may facilitate alien species invasion into new areas, particularly for species from warm native ranges introduced into areas currently marginal for temperature. Although conclusions from modelling approaches and experimental studies are generally similar, combining the two approaches has rarely occurred. The aim of this study was to validate species distribution models by conducting field trials in sites of differing suitability as predicted by the models, thus increasing confidence in their ability to assess invasion risk. Three recently naturalized alien plants in New Zealand were used as study species (Archontophoenix cunninghamiana, Psidium guajava and Schefflera actinophylla): they originate from warm native ranges, are woody bird-dispersed species and of concern as potential weeds. Seedlings were grown in six sites across the country, differing both in climate and suitability (as predicted by the species distribution models). Seedling growth and survival were recorded over two summers and one or two winter seasons, and temperature and precipitation were monitored hourly at each site. Additionally, alien seedling performances were compared to those of closely related native species (Rhopalostylis sapida, Lophomyrtus bullata and Schefflera digitata). Furthermore, half of the seedlings were sprayed with pesticide, to investigate whether enemy release may influence performance. The results showed large differences in growth and survival of the alien species among the six sites. In the more suitable sites, performance was frequently higher compared to the native species. Leaf damage from invertebrate herbivory was low for both alien and native seedlings, with little evidence that the alien species should have an advantage over the native species because of enemy release. Correlations between performance in the field and predicted suitability of species distribution models were generally high. The projected increase in minimum temperature and reduced

  14. A Quantitative Structure Activity Relationship for acute oral toxicity of pesticides on rats: Validation, domain of application and prediction.

    Science.gov (United States)

    Hamadache, Mabrouk; Benkortbi, Othmane; Hanini, Salah; Amrane, Abdeltif; Khaouane, Latifa; Si Moussa, Cherif

    2016-02-13

    Quantitative Structure Activity Relationship (QSAR) models are expected to play an important role in the risk assessment of chemicals on humans and the environment. In this study, we developed a validated QSAR model to predict acute oral toxicity of 329 pesticides to rats because a few QSAR models have been devoted to predict the Lethal Dose 50 (LD50) of pesticides on rats. This QSAR model is based on 17 molecular descriptors, and is robust, externally predictive and characterized by a good applicability domain. The best results were obtained with a 17/9/1 Artificial Neural Network model trained with the Quasi Newton back propagation (BFGS) algorithm. The prediction accuracy for the external validation set was estimated by the Q(2)ext and the root mean square error (RMS) which are equal to 0.948 and 0.201, respectively. 98.6% of external validation set is correctly predicted and the present model proved to be superior to models previously published. Accordingly, the model developed in this study provides excellent predictions and can be used to predict the acute oral toxicity of pesticides, particularly for those that have not been tested as well as new pesticides.

  15. Validation of Normal Tissue Complication Probability Predictions in Individual Patient: Late Rectal Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Semenenko, Vladimir A., E-mail: vsemenenko@LandauerMP.com [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Tarima, Sergey S. [Division of Biostatistics, Institute for Health and Society, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Devisetty, Kiran [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Pelizzari, Charles A.; Liauw, Stanley L. [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States)

    2013-03-15

    Purpose: To perform validation of risk predictions for late rectal toxicity (LRT) in prostate cancer obtained using a new approach to synthesize published normal tissue complication data. Methods and Materials: A published study survey was performed to identify the dose-response relationships for LRT derived from nonoverlapping patient populations. To avoid mixing models based on different symptoms, the emphasis was placed on rectal bleeding. The selected models were used to compute the risk estimates of grade 2+ and grade 3+ LRT for an independent validation cohort composed of 269 prostate cancer patients with known toxicity outcomes. Risk estimates from single studies were combined to produce consolidated risk estimates. An agreement between the actuarial toxicity incidence 3 years after radiation therapy completion and single-study or consolidated risk estimates was evaluated using the concordance correlation coefficient. Goodness of fit for the consolidated risk estimates was assessed using the Hosmer-Lemeshow test. Results: A total of 16 studies of grade 2+ and 5 studies of grade 3+ LRT met the inclusion criteria. The consolidated risk estimates of grade 2+ and 3+ LRT were constructed using 3 studies each. For grade 2+ LRT, the concordance correlation coefficient for the consolidated risk estimates was 0.537 compared with 0.431 for the best-fit single study. For grade 3+ LRT, the concordance correlation coefficient for the consolidated risk estimates was 0.477 compared with 0.448 for the best-fit single study. No evidence was found for a lack of fit for the consolidated risk estimates using the Hosmer-Lemeshow test (P=.531 and P=.397 for grade 2+ and 3+ LRT, respectively). Conclusions: In a large cohort of prostate cancer patients, selected sets of consolidated risk estimates were found to be more accurate predictors of LRT than risk estimates derived from any single study.

  16. Validation of the Gravity Model in Predicting the Global Spread of Influenza

    Directory of Open Access Journals (Sweden)

    Dejian Lai

    2011-07-01

    Full Text Available The gravity model is often used in predicting the spread of influenza. We use the data of influenza A (H1N1 to check the model’s performance and validation, in order to determine the scope of its application. In this article, we proposed to model the pattern of global spread of the virus via a few important socio-economic indicators. We applied the epidemic gravity model for modelling the virus spread globally through the estimation of parameters of a generalized linear model. We compiled the daily confirmed cases of influenza A (H1N1 in each country as reported to the WHO and each state in the USA, and established the model to describe the relationship between the confirmed cases and socio-economic factors such as population size, per capita gross domestic production (GDP, and the distance between the countries/states and the country where the first confirmed case was reported (i.e., Mexico. The covariates we selected for the model were all statistically significantly associated with the global spread of influenza A (H1N1. However, within the USA, the distance and GDP were not significantly associated with the number of confirmed cases. The combination of the gravity model and generalized linear model provided a quick assessment of pandemic spread globally. The gravity model is valid if the spread period is long enough for estimating the model parameters. Meanwhile, the distance between donor and recipient communities has a good gradient. Besides, the spread should be at the early stage if a single source is taking into account.

  17. Validation of a Simple Scoring System to Predict Sorafenib Effectiveness in Patients with Hepatocellular Carcinoma.

    Science.gov (United States)

    Di Costanzo, Giovan Giuseppe; Casadei Gardini, Andrea; Marisi, Giorgia; Foschi, Francesco Giuseppe; Scartozzi, Mario; Granata, Rocco; Faloppi, Luca; Cascinu, Stefano; Silvestris, Nicola; Brunetti, Oronzo; Palmieri, Vincenzo Ostilio; Ercolani, Giorgio; Tortora, Raffaella

    2017-08-03

    Sorafenib is recommended for the treatment of advanced-stage hepatocellular carcinoma (HCC). Nonetheless, it is expensive, effective in few patients, and may cause significant adverse effects. Therefore, accurate selection of patients is needed. In a previous study, we constructed a simple scoring system to predict patients' outcomes based on the occurrence of sorafenib adverse effects. The present study aimed to validate this scoring system in a real-life cohort of HCC patients. Clinical records of 279 outpatients treated with sorafenib in eight Italian centers were retrospectively analyzed. Adverse effects considered to calculate the score were skin toxicity, diarrhea, and arterial hypertension, occurring during the first month of therapy. For each adverse effect, 1 point was assigned if present; and 0 points if absent (resulting in a total score between 0 and 3). Median overall survival (OS) was 10.8 months and median time to progression (TTP) was 5.1 months. At multivariate analysis, performance status, α-fetoprotein (AFP), and Child-Pugh score were independently associated with TTP and OS. A progressive increase of OS and TTP was observed in patients with scores from 0 to 3 (p < 0.001). Six-, 12-, and 24-month survival probabilities were 55.1, 24.5, and 7.9% in score 0 patients, and 100, 80.9, and 46.2% in score 3 patients, respectively. Complete response was observed in one patient (0.4%), partial responses in 41 (15.2%), and stable disease in 117 (43.5%). The disease control rate in patients with scores of 0, 1, 2, and 3 was 34.3, 51.6, 80.9, and 96.3%, respectively (p < 0.001). Complete or partial responses were not observed in score 0 patients. We have validated a useful scoring system to predict outcomes in sorafenib-treated HCC patients. This score is easy to calculate and suitable for implementation in daily clinical practice.

  18. A Validity Study of the Pain Apperception Test

    Science.gov (United States)

    Haase, Richard F.; And Others

    1975-01-01

    This study assessed the validity of the Pain Apperception Test (PAT) against an accepted and validated predictive measure of pain tolerance, a Kinesthetic After Effects Task (KAE). As well, it replicated an earlier finding by Petrovich that suggested that scores derived from the PAT are related significantly to neuroticism. (Author/RK)

  19. An Extension of the Validation of SCALE (SAS2H) Isotopic Predictions for PWR Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    DeHart, M.D.

    1993-01-01

    Isotopic characterization of spent fuel via depletion and decay calculations is necessary for determination of source terms for subsequent system analyses involving heat transfer, radiation shielding, isotopic migration, etc. Unlike fresh fuel assumptions typically employed in the criticality safety analysis of spent fuel configurations, burnup credit applications also rely on depletion and decay calculations to predict the isotopic composition of spent fuel. These isotopics are used in subsequent criticality calculations to assess the reduced worth of spent fuel. To validate the codes and data used in depletion approaches, experimental measurements are compared with numerical predictions for relevant spent fuel samples. Such comparisons have been performed in earlier work at the Oak Ridge National Laboratory (ORNL). This report describes additional independent measurements and corresponding calculations, which supplement the results of the earlier work. The current work includes measured isotopic data from 19 spent fuel samples obtained from the Italian Trino Vercelles pressurized-water reactor (PWR) and the U.S. Turkey Point Unit 3 PWR. In addition, an approach to determine biases and uncertainties between calculated and measured isotopic concentrations is discussed, together with a method to statistically combine these terms to obtain a conservative estimate of spent fuel isotopic concentrations. Results are presented based on the combination of measured-to-calculated ratios for earlier work and the current analyses. The results described herein represent an extension to a new reactor design not included in the earlier work, and spent fuel samples with enrichment as high as 3.9 wt % {sup 235}U. Results for the current work are found to be, for the most part, consistent with the findings of the earlier work. This consistency was observed for results obtained from each of two different cross-section libraries and suggests that the estimated biases determined for

  20. Validation of trauma scales: ISS, NISS, RTS and TRISS for predicting mortality in a Colombian population.

    Science.gov (United States)

    Valderrama-Molina, Carlos Oliver; Giraldo, Nelson; Constain, Alfredo; Puerta, Andres; Restrepo, Camilo; León, Alba; Jaimes, Fabián

    2017-02-01

    Our purpose was to validate the performance of the ISS, NISS, RTS and TRISS scales as predictors of mortality in a population of trauma patients in a Latin American setting. Subjects older than 15 years with diagnosis of trauma, lesions in two or more body areas according to the AIS and whose initial attention was at the hospital in the first 24 h were included. The main outcome was inpatient mortality. Secondary outcomes were admission to the intensive care unit, requirement of mechanical ventilation and length of stay. A logistic regression model for hospital mortality was fitted with each of the scales as an independent variable, and its predictive accuracy was evaluated through discrimination and calibration statistics. Between January 2007 and July 2015, 4085 subjects were enrolled in the study. 84.2% (n = 3442) were male, the mean age was 36 years (SD = 16), and the most common trauma mechanism was blunt type (80.1%; n = 3273). The medians of ISS, NISS, TRISS and RTS were: 14 (IQR = 10-21), 17 (IQR = 11-27), 4.21 (IQR = 2.95-5.05) and 7.84 (IQR = 6.90-7.84), respectively. Mortality was 9.3%, and the discrimination for ISS, NISS, TRISS and RTS was: AUC 0.85, 0.89, 0.86 and 0.92, respectively. No one scale had appropriate calibration. Determining the severity of trauma is an essential tool to guide treatment and establish the necessary resources for attention. In a Colombian population from a capital city, trauma scales have adequate performance for the prediction of mortality in patients with trauma.

  1. Incremental validity of the WJ III COG: Limited predictive effects beyond the GIA-E.

    Science.gov (United States)

    McGill, Ryan J; Busse, R T

    2015-09-01

    This study is an examination of the incremental validity of Cattell-Horn-Carroll (CHC) broad clusters from the Woodcock-Johnson III Tests of Cognitive Abilities (WJ III COG) for predicting scores on the Woodcock-Johnson III Tests of Achievement (WJ III ACH). The participants were children and adolescents, ages 6-18 (n = 4,722), drawn from the WJ III standardization sample. The sample was nationally stratified and proportional to U.S. census estimates for race/ethnicity, parent education level, and geographic region. Hierarchical multiple regression analyses were used to assess for cluster-level effects after controlling for the variance accounted for by the General Intellectual Ability-Extended (GIA-E) composite score. The results were interpreted using the R²/ΔR² statistic as the effect size indicator. Consistent with previous studies, the GIA-E accounted for statistically and clinically significant portions of WJ III ACH cluster score variance, with R2 values ranging from .29 to .56. WJ III COG CHC cluster scores collectively provided statistically significant incremental variance beyond the GIA-E in all of the regression models, although the effect sizes were consistently negligible to small (Average ΔR2(CHC) = .06), with significant effects observed only in the Oral Expression model (ΔR²(CHC) = .23). Individually, the WJ III COG cluster scores accounted for mostly small portions of achievement variance across the prediction models, with a large effect found for the Comprehension-Knowledge cluster in the Oral Expression model (ΔR²(Gc) = .23). The potential clinical and theoretical implications of these results are discussed.

  2. Development and validation of a 3-D model to predict knee joint loading during dynamic movement.

    Science.gov (United States)

    McLean, S G; Su, A; van den Bogert, A J

    2003-12-01

    The purpose of this study was to develop a subject-specific 3-D model of the lower extremity to predict neuromuscular control effects on 3-D knee joint loading during movements that can potentially cause injury to the anterior cruciate ligament (ACL) in the knee. The simulation consisted of a forward dynamic 3-D musculoskeletal model of the lower extremity, scaled to represent a specific subject. Inputs of the model were the initial position and velocity of the skeletal elements, and the muscle stimulation patterns. Outputs of the model were movement and ground reaction forces, as well as resultant 3-D forces and moments acting across the knee joint. An optimization method was established to find muscle stimulation patterns that best reproduced the subject's movement and ground reaction forces during a sidestepping task. The optimized model produced movements and forces that were generally within one standard deviation of the measured subject data. Resultant knee joint loading variables extracted from the optimized model were comparable to those reported in the literature. The ability of the model to successfully predict the subject's response to altered initial conditions was quantified and found acceptable for use of the model to investigate the effect of altered neuromuscular control on knee joint loading during sidestepping. Monte Carlo simulations (N = 100,000) using randomly perturbed initial kinematic conditions, based on the subject's variability, resulted in peak anterior force, valgus torque and internal torque values of 378 N, 94 Nm and 71 Nm, respectively, large enough to cause ACL rupture. We conclude that the procedures described in this paper were successful in creating valid simulations of normal movement, and in simulating injuries that are caused by perturbed neuromuscular control.

  3. On the Predictability of Computer simulations: Advances in Verification and Validation

    KAUST Repository

    Prudhomme, Serge

    2014-01-06

    We will present recent advances on the topics of Verification and Validation in order to assess the reliability and predictability of computer simulations. The first part of the talk will focus on goal-oriented error estimation for nonlinear boundary-value problems and nonlinear quantities of interest, in which case the error representation consists of two contributions: 1) a first contribution, involving the residual and the solution of the linearized adjoint problem, which quantifies the discretization or modeling error; and 2) a second contribution, combining higher-order terms that describe the linearization error. The linearization error contribution is in general neglected with respect to the discretization or modeling error. However, when nonlinear effects are significant, it is unclear whether ignoring linearization effects may produce poor convergence of the adaptive process. The objective will be to show how both contributions can be estimated and employed in an adaptive scheme that simultaneously controls the two errors in a balanced manner. In the second part of the talk, we will present novel approach for calibration of model parameters. The proposed inverse problem not only involves the minimization of the misfit between experimental observables and their theoretical estimates, but also an objective function that takes into account some design goals on specific design scenarios. The method can be viewed as a regularization approach of the inverse problem, one, however, that best respects some design goals for which mathematical models are intended. The inverse problem is solved by a Bayesian method to account for uncertainties in the data. We will show that it shares the same structure as the deterministic problem that one would obtain by multi-objective optimization theory. The method is illustrated on an example of heat transfer in a two-dimensional fin. The proposed approach has the main benefit that it increases the confidence in predictive

  4. Performance prediction and validation of equilibrium modeling for gasification of cashew nut shell char

    Directory of Open Access Journals (Sweden)

    M. Venkata Ramanan

    2008-09-01

    Full Text Available Cashew nut shell, a waste product obtained during deshelling of cashew kernels, had in the past been deemed unfit as a fuel for gasification owing to its high occluded oil content. The oil, a source of natural phenol, oozes upon gasification, thereby clogging the gasifier throat, downstream equipment and associated utilities with oil, resulting in ineffective gasification and premature failure of utilities due to its corrosive characteristics. To overcome this drawback, the cashew shells were de-oiled by charring in closed chambers and were subsequently gasified in an autothermal downdraft gasifier. Equilibrium modeling was carried out to predict the producer gas composition under varying performance influencing parameters, viz., equivalence ratio (ER, reaction temperature (RT and moisture content (MC. The results were compared with the experimental output and are presented in this paper. The model is quite satisfactory with the experimental outcome at the ER applicable to gasification systems, i.e., 0.15 to 0.30. The results show that the mole fraction of (i H2, CO and CH4 decreases while (N2 + H2O and CO2 increases with ER, (ii H2 and CO increases while CH4, (N2 + H2O and CO2 decreases with reaction temperature, (iii H2, CH4, CO2 and (N2 + H2O increases while CO decreases with moisture content. However at an equivalence ratio less than 0.15, the model predicts an unrealistic composition and is observed to be non valid below this ER.

  5. Spino-pelvic parameters after surgery can be predicted: a preliminary formula and validation of standing alignment.

    Science.gov (United States)

    Lafage, Virginie; Schwab, Frank; Vira, Shaleen; Patel, Ashish; Ungar, Benjamin; Farcy, Jean-Pierre

    2011-06-01

    Prospective and retrospective radiographic study of adult patients with spinal deformities. Construct predictive models for pelvic tilt (PT) and global sagittal balance (sagittal vertical axis [SVA]) and evaluate the effectiveness of these predictive models against a group of patients after pedicle subtraction osteotomy. Spinal balance involves a complex interaction between the pelvis and vertebral column. In the setting of adult spinal deformity, prediction of postoperative alignment can be challenging. The study included 219 adult patients treated for spinal deformity. Full-length standing films were available for all subjects. Multilinear models with a stepwise condition were used on the first group of patients (n = 179) to predict PT and global sagittal balance (measured by the SVA). Prediction models were then applied on a second group of patients (n = 40) to estimate postoperative radiographic parameters after pedicle subtraction osteotomy surgery. Differences between estimated parameters and real values were evaluated. Multilinear regression analysis applied on the first group of patients led to a predictive formula for PT (r = 0.93, standard error = 4.4°) using the following parameters: pelvic incidence, maximal lordosis, and maximal kyphosis. These parameters with the addition of the predicted PT were then used to predict the SVA (r = 0.89, standard error = 32 mm). Validation of predictive models (second group of patients) used pelvic incidence and postoperative sagittal curves. Postoperative PT was predicted with a mean error of 4.3° (SD 3.5°) and postoperative SVA was predicted with a mean error of 29 mm (SD = 23 mm). This is the first study to develop and validate pragmatic predictive models for key spino-pelvic parameters (PT and SVA) in the setting of adult spinal deformity. Using a morphologic pelvic parameter (pelvic incidence) and spinal parameters modifiable through surgery (lumbar lordosis and thoracic kyphosis), postoperative sagittal

  6. The Relationship between SAT® Scores and Retention to the Second Year: Replication with the 2010 SAT Validity Sample. Statistical Report 2013-1

    Science.gov (United States)

    Mattern, Krista D.; Patterson, Brian F.

    2013-01-01

    The College Board formed a research consortium with four-year colleges and universities to build a national higher education database with the primary goal of validating the revised SAT for use in college admission. A study by Mattern and Patterson (2009) examined the relationship between SAT scores and retention to the second year. The sample…

  7. The Relationship between SAT Scores and Retention to the Second Year: Replication with 2009 SAT Validity Sample. Statistical Report 2011-3

    Science.gov (United States)

    Mattern, Krista D.; Patterson, Brian F.

    2012-01-01

    The College Board formed a research consortium with four-year colleges and universities to build a national higher education database with the primary goal of validating the revised SAT for use in college admission. A study by Mattern and Patterson (2009) examined the relationship between SAT scores and retention to the second year of college. The…

  8. Development and external validation of a faecal immunochemical test-based prediction model for colorectal cancer detection in symptomatic patients

    OpenAIRE

    Alves, Maria Teresa; Álvarez-Sánchez, Victoria; Ferrandez, Ángel; Rodríguez-Alcalde, Daniel; ,; Cubiella, Joaquín; Vega, Pablo; Salve, María; Díaz-Ondina, Marta; Blanco, Irene; Macía, Pedro; Sánchez, Eloy; Fernández-Seara, Javier; Alves, María Teresa; Quintero, Enrique

    2016-01-01

    Background Risk prediction models for colorectal cancer (CRC) detection in symptomatic patients based on available biomarkers may improve CRC diagnosis. Our aim was to develop, compare with the NICE referral criteria and externally validate a CRC prediction model, COLONPREDICT, based on clinical and laboratory variables. Methods This prospective cross-sectional study included consecutive patients with gastrointestinal symptoms referred for colonoscopy between March 2012 and September 2013 in ...

  9. Prediction and validation of potential pathogenic microRNAs involved in Phytophthora infestans infection.

    Science.gov (United States)

    Cui, Juanjuan; Luan, Yushi; Wang, Weichen; Zhai, Junmiao

    2014-03-01

    Being one kind of approximately 22nt long small RNA, miRNA has shown its roles in host-pathogen interaction, providing one possible way for pathogen infection. Though Phytophthora infestans is a major pathogen that causes devastating late blight of potato, tomato and so on, so far there have not been any systematic researches on miRNAs and even pathogenic miRNAs in P. infestans. Here, for the first time we comprehensively predicted and identified pathogenic miRNAs that may exist in P. infestans. First, a total of 128 putative miRNAs belonging to 66 miRNA family were identified by bioinformatic approaches. Then, 33 vital pathogenic miRNAs were screened by constructing miRNA-miRNA relationship networks. Finally, four potential pathogenic miRNAs were chosen for detection, two of which are chosen for validation. The expression quantity of pi-miR466 and pi-miR1918 changed dramatically during incubation of tomato leaves, implying that they are potential pathogenic miRNAs.

  10. An Empirical Validation of Object-Oriented Design Metrics for Fault Prediction

    Directory of Open Access Journals (Sweden)

    Jie Xu

    2008-01-01

    Full Text Available Problem Statement: Object-oriented design has become a dominant method in software industry and many design metrics of object-oriented programs have been proposed for quality prediction, but there is no well-accepted statement on how significant those metrics are. In this study, empirical analysis is carried out to validate object-oriented design metrics for defects estimation. Approach: The Chidamber and Kemerer metrics suite is adopted to estimate the number of defects in the programs, which are extracted from a public NASA data set. The techniques involved are statistical analysis and neuro-fuzzy approach. Results: The results indicate that SLOC, WMC, CBO and RFC are reliable metrics for defect estimation. Overall, SLOC imposes most significant impact on the number of defects. Conclusions/Recommendations: The design metrics are closely related to the number of defects in OO classes, but we can not jump to a conclusion by using one analysis technique. We recommend using neuro-fuzzy approach together with statistical techniques to reveal the relationship between metrics and dependent variables, and the correlations among those metrics also have to be considered.

  11. Role of Validation and Predictions in Modeling: Specific Examples from Semiconductor Industry Applications

    Science.gov (United States)

    Shankar, Sadasivan

    2012-02-01

    With the advent of newer non-Silicon materials, using modeling to estimate properties are becoming necessary for process technology development. Since these materials are integrated as part of larger devices, interfaces and material domains are increasingly modulating properties of materials. Unlike in bulk materials, electronic and thermodynamic properties are difficult to characterize in these material structures as the device sizes overlap with material domains. We will illustrate specific cases from semiconductor processing and property estimation on the importance of verification of models for internal consistency and validation with experimental data. Given the discrepancy of scales between predictions and measurement, techniques need to bridge them. In addition, models that are developed need to be modular with open interfaces for cross-checking and integration across scales as indicated in the recently announced Materials Genome Initiative.[4pt] [1] President's initiative on Materials Genome Initiative for Global Competitiveness, June 2011[2pt] [2] S. Shankar, B. V. McKoy, W. L. Morgan, ``Self-Consistent Modeling of Weakly Ionized Plasmas-Challenges in Quantum and Classical mechanics,'' Sixth U.S. National Congress on Computational Mechanics, U.S. Association for Computational Mechanics, Dearborn, Michigan, (2001)

  12. Predicting NCLEX success with the HESI Exit Exam: fourth annual validity study.

    Science.gov (United States)

    Nibert, Ainslie T; Young, Anne; Adamson, Carolyn

    2008-01-01

    The fourth annual validity study of the Health Education Systems, Inc. (HESI) Exit Exam was designed to examine not only the accuracy of the examination in predicting NCLEX success but also the degree of risk for failure of the licensure examination associated with specific scoring intervals. A descriptive comparative design was used to examine the data provided by schools of nursing regarding students' NCLEX outcomes in the 1999-2000 academic year. As in the 3 previous studies, the examination was found to be a highly accurate predictor of NCLEX success (98.46%). Each scoring interval was significantly different from each of the other scoring intervals (P = .001). In fact, for the combined group of registered nurse and practical nurse students, the percentage of students who failed the NCLEX more than doubled with each successively lower scoring interval. These findings provide the information faculties needed to make evidence-based decisions regarding students' risks for NCLEX failure. Additionally, frequency data were obtained from this survey regarding the use of the examination as a benchmark for progression and remediation, and these findings may also be useful to faculties that are considering establishing such programs.

  13. The predictive validity of selection criteria for personnel management students at a tertiary institution

    Directory of Open Access Journals (Sweden)

    S. Swanepoel

    1998-06-01

    Full Text Available Tertiary institutions are confronted daily with the issues surrounding the creation of admission requirements for prospective students that ensure academic success. In a changing South Africa, with its increasing emphasis on individual rights, fair and equitable selection techniques are a priority. The target population for this investigation was four consecutive groups of first-year Personnel Management students who were enrolled for the National Diploma: Personnel Management. The survey population consisted of 293 students. The aim of the study has been achieved by the proof that specific fa :tors of fields of the measure instruments do have prediction validity. These findings can be used with fruit in search of a selection model for academic achievement. Opsomming Tersiere instellings word daagliks gekonfronteer met die kwessies betreffende die daarstel van toelatingsvereistes vir voomemende studente wat akademiese sukses sal verseker. In 'n veranderende Suid-Afnka, met die toenemende klem op mdividuele regte, is regverdige en billike keuringskriteria 'n prioriteit. Die teikenpopulasie vir hierdie ondersoek was vier agtereenvolgende groepe eerstej'aarpersoneelbestuur- studente wat vir die Nasionale Diploma: Personeelbestuur ingeskrvf was. Die opnamepopulasie het uit 293 studente bestaan. Die doel van die studie is bereik deur die bewys dat spesifieke faktore of velde van die meetinstrumente voorspellingsgeldigheid besit. Hierdie bevmdinge kan met vrug gebruik word in die soeke na 'n keuringsmodel vir akademiese prestasies.

  14. A Validated Analytical Model for Availability Prediction of IPTV Services in VANETs

    Directory of Open Access Journals (Sweden)

    Bernd E. Wolfinger

    2014-12-01

    Full Text Available In vehicular ad hoc networks (VANETs, besides the original applications typically related to traffic safety, we nowadays can observe an increasing trend toward infotainment applications, such as IPTV services. Quality of experience (QoE, as observed by the end users of IPTV, is highly important to guarantee adequate user acceptance for the service. In IPTV, QoE is mainly determined by the availability of TV channels for the users. This paper presents an efficient and rather generally applicable analytical model that allows one to predict the blocking probability of TV channels, both for channel-switching-induced, as well as for handover-induced blocking events. We present the successful validation of the model by means of simulation, and we introduce a new measure for QoE. Numerous case studies illustrate how the analytical model and our new QoE measure can be applied successfully for the dimensioning of IPTV systems, taking into account the QoE requirements of the IPTV service users in strongly diverse traffic scenarios.

  15. A tunnel study to validate motor vehicle emission prediction software in Australia

    Science.gov (United States)

    Smit, R.; Kingston, P.; Wainwright, D. H.; Tooker, R.

    2017-02-01

    A tunnel emissions study was conducted to (partially) validate the Australian vehicle emissions software COPERT Australia and PIARC emission factors. The in-tunnel fleet mix differs substantially from the average on-road fleet, leading to lower emissions by a factor of about 2. Simulation with the PΔP software found that in-tunnel air-flow compensates to a large extent for road gradient impacts on NOx emissions. PIARC emission factors are conservative and exhibit the largest prediction errors, except for one very good agreement for LDV NOx. COPERT Australia is generally accurate at fleet level for CO, NOx, PM2.5 and PM10, when compared with other international studies, and consistently underestimates emissions by 7%-37%, depending on the pollutant. Possible contributing factors are under-representation of high/excessive emitting vehicles, inaccurate mileage correction factors, and lack of empirical emissions data for Australian diesel cars. The study results demonstrate a large uncertainty in speciated VOC and PAH emission factors.

  16. Prediction and validation of protein intermediate states from structurally rich ensembles and coarse-grained simulations

    Science.gov (United States)

    Orellana, Laura; Yoluk, Ozge; Carrillo, Oliver; Orozco, Modesto; Lindahl, Erik

    2016-08-01

    Protein conformational changes are at the heart of cell functions, from signalling to ion transport. However, the transient nature of the intermediates along transition pathways hampers their experimental detection, making the underlying mechanisms elusive. Here we retrieve dynamic information on the actual transition routes from principal component analysis (PCA) of structurally-rich ensembles and, in combination with coarse-grained simulations, explore the conformational landscapes of five well-studied proteins. Modelling them as elastic networks in a hybrid elastic-network Brownian dynamics simulation (eBDIMS), we generate trajectories connecting stable end-states that spontaneously sample the crystallographic motions, predicting the structures of known intermediates along the paths. We also show that the explored non-linear routes can delimit the lowest energy passages between end-states sampled by atomistic molecular dynamics. The integrative methodology presented here provides a powerful framework to extract and expand dynamic pathway information from the Protein Data Bank, as well as to validate sampling methods in general.

  17. Specificity matters: criterion-related validity of contextualized and facet measures of conscientiousness in predicting college student performance.

    Science.gov (United States)

    Woo, Sang Eun; Jin, Jing; LeBreton, James M

    2015-01-01

    To enhance the predictive validity of self-report personality measures, 2 distinct ways of increasing specificity of personality measures have been proposed in the literature-contextual specificity (i.e., providing a contextual referent) and content specificity (i.e., focusing on more specific constructs such as the Big Five facets). This study extends this line of research by examining whether there is an optimal way to configure, align, or integrate contextual and content specificity using measures of conscientiousness to predict college student success. A sample of 478 undergraduate students completed 4 measures of conscientiousness that varied in the level of content and contextual specificity. These forms of specificity were crossed to yield 4 distinct measures of conscientiousness. We then evaluated and compared the relative importance and the incremental importance of these different measures in the prediction of academic success. Superior predictive validity was found for both contextualized and facet measures of conscientiousness compared to a measure of global conscientiousness in predicting grade-point average and a broader behavioral criterion of student performance. When contextual and content specificity approaches were compared and combined, we observed the strongest predictive validity when the level of specificity is appropriately matched between predictor and criterion.

  18. Recidivism in female offenders: PCL-R lifestyle factor and VRAG show predictive validity in a German sample.

    Science.gov (United States)

    Eisenbarth, Hedwig; Osterheider, Michael; Nedopil, Norbert; Stadtland, Cornelis

    2012-01-01

    A clear and structured approach to evidence-based and gender-specific risk assessment of violence in female offenders is high on political and mental health agendas. However, most data on the factors involved in risk-assessment instruments are based on data of male offenders. The aim of the present study was to validate the use of the Psychopathy Checklist Revised (PCL-R), the HCR-20 and the Violence Risk Appraisal Guide (VRAG) for the prediction of recidivism in German female offenders. This study is part of the Munich Prognosis Project (MPP). It focuses on a subsample of female delinquents (n = 80) who had been referred for forensic-psychiatric evaluation prior to sentencing. The mean time at risk was 8 years (SD = 5 years; range: 1-18 years). During this time, 31% (n = 25) of the female offenders were reconvicted, 5% (n = 4) for violent and 26% (n = 21) for non-violent re-offenses. The predictive validity of the PCL-R for general recidivism was calculated. Analysis with receiver-operating characteristics revealed that the PCL-R total score, the PCL-R antisocial lifestyle factor, the PCL-R lifestyle factor and the PCL-R impulsive and irresponsible behavioral style factor had a moderate predictive validity for general recidivism (area under the curve, AUC = 0.66, p = 0.02). The VRAG has also demonstrated predictive validity (AUC = 0.72, p = 0.02), whereas the HCR-20 showed no predictive validity. These results appear to provide the first evidence that the PCL-R total score and the antisocial lifestyle factor are predictive for general female recidivism, as has been shown consistently for male recidivists. The implications of these findings for crime prevention, prognosis in women, and future research are discussed.

  19. Validity and reliability of bioelectrical impedance analysis and skinfold thickness in predicting body fat in military personnel.

    Science.gov (United States)

    Aandstad, Anders; Holtberget, Kristian; Hageberg, Rune; Holme, Ingar; Anderssen, Sigmund A

    2014-02-01

    Previous studies show that body composition is related to injury risk and physical performance in soldiers. Thus, valid methods for measuring body composition in military personnel are needed. The frequently used body mass index method is not a valid measure of body composition in soldiers, but reliability and validity of alternative field methods are less investigated in military personnel. Thus, we carried out test and retest of skinfold (SKF), single frequency bioelectrical impedance analysis (SF-BIA), and multifrequency bioelectrical impedance analysis measurements in 65 male and female soldiers. Several validated equations were used to predict percent body fat from these methods. Dual-energy X-ray absorptiometry was also measured, and acted as the criterion method. Results showed that SF-BIA was the most reliable method in both genders. In women, SF-BIA was also the most valid method, whereas SKF or a combination of SKF and SF-BIA produced the highest validity in men. Reliability and validity varied substantially among the equations examined. The best methods and equations produced test-retest 95% limits of agreement below ±1% points, whereas the corresponding validity figures were ±3.5% points. Each investigator and practitioner must consider whether such measurement errors are acceptable for its specific use. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

  20. Development and Validation of Non-Integrative, Self-Limited, and Replicating Minicircles for Safe Reporter Gene Imaging of Cell-Based Therapies

    Science.gov (United States)

    Ronald, John A.; Cusso, Lorena; Chuang, Hui-Yen; Yan, Xinrui; Dragulescu-Andrasi, Anca; Gambhir, Sanjiv Sam

    2013-01-01

    Reporter gene (RG) imaging of cell-based therapies provides a direct readout of therapeutic efficacy by assessing the fate of implanted cells. To permit long-term cellular imaging, RGs are traditionally required to be integrated into the cellular genome. This poses a potential safety risk and regulatory bottleneck for clinical translation as integration can lead to cellular transformation. To address this issue, we have developed non-integrative, replicating minicircles (MCs) as an alternative platform for safer monitoring of cells in living subjects. We developed both plasmids and minicircles containing the scaffold/matrix attachment regions (S/MAR) of the human interferon-beta gene, driven by the CMV promoter, and expressing the bioluminescence RG firefly luciferase. Constructs were transfected into breast cancer cells, and expanded S/MAR minicircle clones showed luciferase signal for greater than 3 months in culture and minicircles remained as episomes. Importantly, luciferase activity in clonal populations was slowly lost over time and this corresponded to a loss of episome, providing a way to reversibly label cells. To monitor cell proliferation in vivo, 1.5×106 cells carrying the S/MAR minicircle were implanted subcutaneously into mice (n = 5) and as tumors developed significantly more bioluminescence signal was noted at day 35 and 43 compared to day 7 post-implant (p<0.05). To our knowledge, this is the first work examining the use of episomal, self-limited, replicating minicircles to track the proliferation of cells using non-invasive imaging in living subjects. Continued development of S/MAR minicircles will provide a broadly applicable vector platform amenable with any of the numerous RG technologies available to allow therapeutic cell fate to be assessed in individual patients, and to achieve this without the need to manipulate the cell's genome so that safety concerns are minimized. This will lead to safe tools to assess treatment response at

  1. Determining the validity of exposure models for environmental epidemiology : predicting electromagnetic fields from mobile phone base stations

    NARCIS (Netherlands)

    Beekhuizen, Johan

    2014-01-01

    One of the key challenges in environmental epidemiology is the exposure assessment of large populations. Spatial exposure models have been developed that predict exposure to the pollutant of interest for large study sizes. However, the validity of these exposure models is often unknown. In this thes

  2. Ultrasonographic quantification of intrinsic hand muscle cross-sectional area; Reliability and validity for predicting muscle strength

    NARCIS (Netherlands)

    Mohseny, Behnam; Nijhuis, Tim H.; Hundepool, Caroline A.; Janssen, Wim G.; Selles, Ruud W.; Coert, J. Henk

    2015-01-01

    Objective To investigate whether ultrasonographic measurement of the cross-sectional area (CSA) of the intrinsic hand muscles can be used to predict muscle strength in a valid and reliable manner, and to determine if this method can be used for follow-up of patients with peripheral nerve injury betw

  3. Differential Predictive Validity of High School GPA and College Entrance Test Scores for University Students in Yemen

    Science.gov (United States)

    Al-Hattami, Abdulghani Ali Dawod

    2012-01-01

    High school grade point average and college entrance test scores are two admission criteria that are currently used by most colleges in Yemen to select their prospective students. Given their widespread use, it is important to investigate their predictive validity to ensure the accuracy of the admission decisions in these institutions. This study…

  4. Predictive modeling of infrared radiative heating in tomato dry-peeling process: Part II. Model validation and sensitivity analysis

    Science.gov (United States)

    A predictive mathematical model was developed to simulate heat transfer in a tomato undergoing double sided infrared (IR) heating in a dry-peeling process. The aims of this study were to validate the developed model using experimental data and to investigate different engineering parameters that mos...

  5. The Validity of SAT® Scores in Predicting First-Year Mathematics and English Grades. Research Report 2012-1

    Science.gov (United States)

    Mattern, Krista D.; Patterson, Brian F.; Kobrin, Jennifer L.

    2012-01-01

    This study examined the validity of the SAT for predicting performance in first-year English and mathematics courses. Results reveal a significant positive relationship between SAT scores and course grades, with slightly higher correlations for mathematics courses compared to English courses. Correlations were estimated by student characteristics…

  6. Predictive validity of the ASAS classification criteria for axial and peripheral spondyloarthritis after follow-up in the ASAS cohort

    DEFF Research Database (Denmark)

    Sepriano, Alexandre; Landewé, Robert; van der Heijde, Désirée

    2016-01-01

    Objective To establish the predictive validity of the Assessment of SpondyloArthritis international Society (ASAS) spondyloarthritis (SpA) classification criteria. Methods 22 centres (N=909 patients) from the initial 29 ASAS centres (N=975) participated in the ASAScohort follow-up study. Patients...

  7. Differential Predictive Validity of High School GPA and College Entrance Test Scores for University Students in Yemen

    Science.gov (United States)

    Al-Hattami, Abdulghani Ali Dawod

    2012-01-01

    High school grade point average and college entrance test scores are two admission criteria that are currently used by most colleges in Yemen to select their prospective students. Given their widespread use, it is important to investigate their predictive validity to ensure the accuracy of the admission decisions in these institutions. This study…

  8. The Predictive Validity of a Computer-Adaptive Assessment of Kindergarten and First-Grade Reading Skills

    Science.gov (United States)

    Clemens, Nathan H.; Hagan-Burke, Shanna; Luo, Wen; Cerda, Carissa; Blakely, Alane; Frosch, Jennifer; Gamez-Patience, Brenda; Jones, Meredith

    2015-01-01

    This study examined the predictive validity of a computer-adaptive assessment for measuring kindergarten reading skills using the STAR Early Literacy (SEL) test. The findings showed that the results of SEL assessments administered during the fall, winter, and spring of kindergarten were moderate and statistically significant predictors of year-end…

  9. Incremental Criterion Validity of the WJ-III COG Clinical Clusters: Marginal Predictive Effects beyond the General Factor

    Science.gov (United States)

    McGill, Ryan J.

    2015-01-01

    The current study examined the incremental validity of the clinical clusters from the Woodcock-Johnson III Tests of Cognitive Abilities (WJ-III COG) for predicting scores on the Woodcock-Johnson III Tests of Achievement (WJ-III ACH). All participants were children and adolescents (N = 4,722) drawn from the nationally representative WJ-III…

  10. Using Structural Equation Modeling to Validate the Theory of Planned Behavior as a Model for Predicting Student Cheating

    Science.gov (United States)

    Mayhew, Matthew J.; Hubbard, Steven M.; Finelli, Cynthia J.; Harding, Trevor S.; Carpenter, Donald D.

    2009-01-01

    The purpose of this paper is to validate the use of a modified Theory of Planned Behavior (TPB) for predicting undergraduate student cheating. Specifically, we administered a survey assessing how the TPB relates to cheating along with a measure of moral reasoning (DIT- 2) to 527 undergraduate students across three institutions; and analyzed the…

  11. A systematic approach to obtain validated partial least square models for predicting lipoprotein subclasses from serum NMR spectra

    NARCIS (Netherlands)

    Mihaleva, V.V.; Schalkwijk, van D.B.; Graaf, de A.A.; Duynhoven, van J.P.M.; Dorsten, van F.A.; Vervoort, J.J.M.; Smilde, A.K.; Westerhuis, J.A.; Jacobs, D.M.

    2014-01-01

    A systematic approach is described for building validated PLS models that predict cholesterol and triglyceride concentrations in lipoprotein subclasses in fasting serum from a normolipidemic, healthy population. The PLS models were built on diffusion-edited (1)H NMR spectra and calibrated on HPLC-de

  12. A systematic approach to obtain validated partial least square models for predicting lipoprotein subclasses from serum nmr spectra

    NARCIS (Netherlands)

    Mihaleva, V.V.; Schalkwijk, D.B. van; Graaf, A.A. de; Duynhoven, J. van; Dorsten, F.A. van; Vervoort, J.; Smilde, A.; Westerhuis, J.A.; Jacobs, D.M.

    2014-01-01

    A systematic approach is described for building validated PLS models that predict cholesterol and triglyceride concentrations in lipoprotein subclasses in fasting serum from a normolipidemic, healthy population. The PLS models were built on diffusion-edited 1H NMR spectra and calibrated on HPLC-deri

  13. Using Structural Equation Modeling to Validate the Theory of Planned Behavior as a Model for Predicting Student Cheating

    Science.gov (United States)

    Mayhew, Matthew J.; Hubbard, Steven M.; Finelli, Cynthia J.; Harding, Trevor S.; Carpenter, Donald D.

    2009-01-01

    The purpose of this paper is to validate the use of a modified Theory of Planned Behavior (TPB) for predicting undergraduate student cheating. Specifically, we administered a survey assessing how the TPB relates to cheating along with a measure of moral reasoning (DIT- 2) to 527 undergraduate students across three institutions; and analyzed the…

  14. Hospitalization for community-acquired febrile urinary tract infection: Validation and impact assessment of a clinical prediction rule

    NARCIS (Netherlands)

    Stalenhoef, J.E. (Janneke E.); van der Starre, W.E. (Willize E.); A. Vollaard (Albert); E.W. Steyerberg (Ewout); Delfos, N.M. (Nathalie M.); E.M.S. Leyten (Eliane M. S.); Koster, T. (Ted); Ablij, H.C. (Hans C.); J.W. van 't Wout (Jan ); J.T. van Dissel (Jaap); C. van Nieuwkoop (Cees)

    2017-01-01

    textabstractBackground: There is a lack of severity assessment tools to identify adults presenting with febrile urinary tract infection (FUTI) at risk for complicated outcome and guide admission policy. We aimed to validate the Prediction Rule for Admission policy in Complicated urinary Tract InfeCt

  15. Multivariate meta-analysis of individual participant data helped externally validate the performance and implementation of a prediction model

    NARCIS (Netherlands)

    K.I.E. Snell (Kym I.E.); H. Hua (Harry); T.P. Debray (Thomas P.A.); J. Ensor (Joie); M.P. Look (Maxime); K.G.M. Moons (Karel G.M.); R.D. Riley (Richard D.)

    2016-01-01

    textabstractObjectives Our aim was to improve meta-analysis methods for summarizing a prediction model's performance when individual participant data are available from multiple studies for external validation. Study Design and Setting We suggest multivariate meta-analysis for jointly synthesizing c

  16. Predictive Validity of ICD-10 Hyperkinetic Disorder Relative to DSM-IV Attention-Deficit/Hyperactivity Disorder among Younger Children

    Science.gov (United States)

    Lahey, Benjamin B.; Pelham, William E.; Chronis, Andrea; Massetti, Greta; Kipp, Heidi; Ehrhardt, Ashley; Lee, Steve S.

    2006-01-01

    Background: Little is known about the predictive validity of hyperkinetic disorder (HKD) as defined by the Diagnostic Criteria for Research for mental and behavioral disorders of the tenth edition of the International Classification of Diseases (ICD-10; World Health Organization, 1993), particularly when the diagnosis is given to younger children.…

  17. External validation and updating of a Dutch prediction model for low hemoglobin deferral in Irish whole blood donors

    NARCIS (Netherlands)

    Baart, A.M.; Atsma, F.; McSweeney, E.N.; Moons, K.G.; Vergouwe, Y.; Kort, W.L. de

    2014-01-01

    BACKGROUND: Recently, sex-specific prediction models for low hemoglobin (Hb) deferral have been developed in Dutch whole blood donors. In the present study, we validated and updated the models in a cohort of Irish whole blood donors. STUDY DESIGN AND METHODS: Prospectively collected data from 45,031

  18. Validity of the MicroDYN Approach: Complex Problem Solving Predicts School Grades beyond Working Memory Capacity

    Science.gov (United States)

    Schweizer, Fabian; Wustenberg, Sascha; Greiff, Samuel

    2013-01-01

    This study examines the validity of the complex problem solving (CPS) test MicroDYN by investigating a) the relation between its dimensions--rule identification (exploration strategy), rule knowledge (acquired knowledge), rule application (control performance)--and working memory capacity (WMC), and b) whether CPS predicts school grades in…

  19. Cross-National Validation of Prognostic Models Predicting Sickness Absence and the Added Value of Work Environment Variables

    NARCIS (Netherlands)

    Roelen, Corne A. M.; Stapelfeldt, Christina M.; Heymans, Martijn W.; van Rhenen, Willem; Labriola, Merete; Nielsen, Claus V.; Bultmann, Ute; Jensen, Chris

    2015-01-01

    Purpose To validate Dutch prognostic models including age, self-rated health and prior sickness absence (SA) for ability to predict high SA in Danish eldercare. The added value of work environment variables to the models' risk discrimination was also investigated. Methods 2,562 municipal eldercare w

  20. Gene expression signatures predict outcome in non-muscle invasive bladder carcinoma - a multi-center validation study

    DEFF Research Database (Denmark)

    Andersen, Lars Dyrskjøt; Zieger, Karsten; Real, Francisco X.

    2007-01-01

    PURPOSE: Clinically useful molecular markers predicting the clinical course of patients diagnosed with non-muscle-invasive bladder cancer are needed to improve treatment outcome. Here, we validated four previously reported gene expression signatures for molecular diagnosis of disease stage and ca...

  1. Characterization and validation of an in silico toxicology model to predict the mutagenic potential of drug impurities*

    Energy Technology Data Exchange (ETDEWEB)

    Valerio, Luis G., E-mail: luis.valerio@fda.hhs.gov [Science and Research Staff, Office of Pharmaceutical Science, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993–0002 (United States); Cross, Kevin P. [Leadscope, Inc., 1393 Dublin Road, Columbus, OH, 43215–1084 (United States)

    2012-05-01

    Control and minimization of human exposure to potential genotoxic impurities found in drug substances and products is an important part of preclinical safety assessments of new drug products. The FDA's 2008 draft guidance on genotoxic and carcinogenic impurities in drug substances and products allows use of computational quantitative structure–activity relationships (QSAR) to identify structural alerts for known and expected impurities present at levels below qualified thresholds. This study provides the information necessary to establish the practical use of a new in silico toxicology model for predicting Salmonella t. mutagenicity (Ames assay outcome) of drug impurities and other chemicals. We describe the model's chemical content and toxicity fingerprint in terms of compound space, molecular and structural toxicophores, and have rigorously tested its predictive power using both cross-validation and external validation experiments, as well as case studies. Consistent with desired regulatory use, the model performs with high sensitivity (81%) and high negative predictivity (81%) based on external validation with 2368 compounds foreign to the model and having known mutagenicity. A database of drug impurities was created from proprietary FDA submissions and the public literature which found significant overlap between the structural features of drug impurities and training set chemicals in the QSAR model. Overall, the model's predictive performance was found to be acceptable for screening drug impurities for Salmonella mutagenicity. -- Highlights: ► We characterize a new in silico model to predict mutagenicity of drug impurities. ► The model predicts Salmonella mutagenicity and will be useful for safety assessment. ► We examine toxicity fingerprints and toxicophores of this Ames assay model. ► We compare these attributes to those found in drug impurities known to FDA/CDER. ► We validate the model and find it has a desired predictive

  2. Cross Cultural Adaptation, Validity, and Reliability of the Farsi Breastfeeding Attrition Prediction Tools in Iranian Pregnant Women

    Science.gov (United States)

    Mortazavi, Forough; Mousavi, Seyed Abbas; Chaman, Reza; Khosravi, Ahmad; Janke, Jill R.

    2015-01-01

    Background: The rate of exclusive breastfeeding in Iran is decreasing. The breastfeeding attrition prediction tools (BAPT) have been validated and used in predicting premature weaning. Objectives: We aimed to translate the BAPT into Farsi, assess its content validity, and examine its reliability and validity to identify exclusive breastfeeding discontinuation in Iran. Materials and Methods: The BAPT was translated into Farsi and the content validity of the Farsi version of the BAPT was assessed. It was administered to 356 pregnant women in the third trimester of pregnancy, who were residents of a city in northeast of Iran. The structural integrity of the four-factor model was assessed in confirmatory factor analysis (CFA) and exploratory factor analysis (EFA). Reliability was assessed using Cronbach’s alpha coefficient and item-subscale correlations. Validity was assessed using the known-group comparison (128 with vs. 228 without breastfeeding experience) and predictive validity (80 successes vs. 265 failures in exclusive breastfeeding). Results: The internal consistency of the whole instrument (49 items) was 0.775. CFA provided an acceptable fit to the a priori four-factor model (Chi-square/df = 1.8, Root Mean Square Error of Approximation (RMSEA) = 0.049, Standardized Root Mean Square Residual (SRMR) = 0.064, Comparative Fit Index (CFI) = 0.911). The difference in means of breastfeeding control (BFC) between the participants with and without breastfeeding experience was significant (P BFC) subscale were higher in women who were on exclusive breastfeeding than women who were not, at four months postpartum (P < 0.05). Conclusions: This study validated the Farsi version of BAPT. It is useful for researchers who want to use it in Iran to identify women at higher risks of Exclusive Breast Feeding (EBF) discontinuation. PMID:26019910

  3. Predictive and concurrent validity of the Braden scale in long-term care: a meta-analysis.

    Science.gov (United States)

    Wilchesky, Machelle; Lungu, Ovidiu

    2015-01-01

    Pressure ulcer prevention is an important long-term care (LTC) quality indicator. While the Braden Scale is a recommended risk assessment tool, there is a paucity of information specifically pertaining to its validity within the LTC setting. We, therefore, undertook a systematic review and meta-analysis comparing Braden Scale predictive and concurrent validity within this context. We searched the Medline, EMBASE, PsychINFO and PubMed databases from 1985-2014 for studies containing the requisite information to analyze tool validity. Our initial search yielded 3,773 articles. Eleven datasets emanating from nine published studies describing 40,361 residents met all meta-analysis inclusion criteria and were analyzed using random effects models. Pooled sensitivity, specificity, positive predictive value (PPV), and negative predictive values were 86%, 38%, 28%, and 93%, respectively. Specificity was poorer in concurrent samples as compared with predictive samples (38% vs. 72%), while PPV was low in both sample types (25 and 37%). Though random effects model results showed that the Scale had good overall predictive ability [RR, 4.33; 95% CI, 3.28-5.72], none of the concurrent samples were found to have "optimal" sensitivity and specificity. In conclusion, the appropriateness of the Braden Scale in LTC is questionable given its low specificity and PPV, in particular in concurrent validity studies. Future studies should further explore the extent to which the apparent low validity of the Scale in LTC is due to the choice of cutoff point and/or preventive strategies implemented by LTC staff as a matter of course.

  4. Evaluating replicability of laboratory experiments in economics.

    Science.gov (United States)

    Camerer, Colin F; Dreber, Anna; Forsell, Eskil; Ho, Teck-Hua; Huber, Jürgen; Johannesson, Magnus; Kirchler, Michael; Almenberg, Johan; Altmejd, Adam; Chan, Taizan; Heikensten, Emma; Holzmeister, Felix; Imai, Taisuke; Isaksson, Siri; Nave, Gideon; Pfeiffer, Thomas; Razen, Michael; Wu, Hang

    2016-03-25

    The replicability of some scientific findings has recently been called into question. To contribute data about replicability in economics, we replicated 18 studies published in the American Economic Review and the Quarterly Journal of Economics between 2011 and 2014. All of these replications followed predefined analysis plans that were made publicly available beforehand, and they all have a statistical power of at least 90% to detect the original effect size at the 5% significance level. We found a significant effect in the same direction as in the original study for 11 replications (61%); on average, the replicated effect size is 66% of the original. The replicability rate varies between 67% and 78% for four additional replicability indicators, including a prediction market measure of peer beliefs.

  5. Predicting DMS-IV cluster B personality disorder criteria from MMPI-2 and Rorschach data: a test of incremental validity.

    Science.gov (United States)

    Blais, M A; Hilsenroth, M J; Castlebury, F; Fowler, J C; Baity, M R

    2001-02-01

    Despite their frequent conjoint clinical use, the incremental validity of Rorschach (Rorschach, 1921/1942) and MMPI (Hathaway & McKinley, 1943) data has not been adequately established, nor has any study to date explored the incremental validity of these tests for predicting Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association, 1994) personality disorders (PDs). In a reanalysis of existing data, we used select Rorschach variables and the MMPI PD scales to predict DSM-IV antisocial, borderline, histrionic, and narcissistic PD criteria in a sample of treatment-seeking outpatients. The correlational findings revealed alimited relation between Rorschach and MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) variables, with only 5 of 30 correlations reaching significance (p MMPI-2 data in predicting the total number of DSM-IV histrionic PD criteria, which were best predicted by Rorschach data, and antisocial PD criteria, which were best predicted by MMPI-2 data. In addition to providing evidence of the incremental validity of Rorschach data, these findings also shed light on the psychological characteristics of the DSM-IV Cluster B PDs.

  6. Predicting environmental suitability for a rare and threatened species (Lao newt, Laotriton laoensis using validated species distribution models.

    Directory of Open Access Journals (Sweden)

    Amanda J Chunco

    Full Text Available The Lao newt (Laotriton laoensis is a recently described species currently known only from northern Laos. Little is known about the species, but it is threatened as a result of overharvesting. We integrated field survey results with climate and altitude data to predict the geographic distribution of this species using the niche modeling program Maxent, and we validated these predictions by using interviews with local residents to confirm model predictions of presence and absence. The results of the validated Maxent models were then used to characterize the environmental conditions of areas predicted suitable for L. laoensis. Finally, we overlaid the resulting model with a map of current national protected areas in Laos to determine whether or not any land predicted to be suitable for this species is coincident with a national protected area. We found that both area under the curve (AUC values and interview data provided strong support for the predictive power of these models, and we suggest that interview data could be used more widely in species distribution niche modeling. Our results further indicated that this species is mostly likely geographically restricted to high altitude regions (i.e., over 1,000 m elevation in northern Laos and that only a minute fraction of suitable habitat is currently protected. This work thus emphasizes that increased protection efforts, including listing this species as endangered and the establishment of protected areas in the region predicted to be suitable for L. laoensis, are urgently needed.

  7. Validation of a Prediction Model for Vaginal Birth after Cesarean Delivery Reveals Unexpected Success in a Diverse American Population

    Science.gov (United States)

    Maykin, Melanie Mai; Mularz, Amanda J.; Lee, Lydia K.; Valderramos, Stephanie Gaw

    2017-01-01

    Objective To investigate the validity of a prediction model for success of vaginal birth after cesarean delivery (VBAC) in an ethnically diverse population. Methods We performed a retrospective cohort study of women admitted at a single academic institution for a trial of labor after cesarean from May 2007 to January 2015. Individual predicted success rates were calculated using the Maternal–Fetal Medicine Units Network prediction model. Participants were stratified into three probability-of-success groups: low (65%). The actual versus predicted success rates were compared. Results In total, 568 women met inclusion criteria. Successful VBAC occurred in 402 (71%), compared with a predicted success rate of 66% (p = 0.016). Actual VBAC success rates were higher than predicted by the model in the low (57 vs. 29%; p < 0.001) and moderate (61 vs. 52%; p = 0.003) groups. In the high probability group, the observed and predicted VBAC rates were the same (79%). Conclusion When the predicted success rate was above 65%, the model was highly accurate. In contrast, for women with predicted success rates <35%, actual VBAC rates were nearly twofold higher in our population, suggesting that they should not be discouraged by a low prediction score.

  8. Convergent Validity of the One-Mile Run and PACER VO2MAX Prediction Models in Middle School Students

    Directory of Open Access Journals (Sweden)

    Ryan D. Burns

    2014-02-01

    Full Text Available FITNESSGRAM uses an equating method to convert Progressive Aerobic Cardiovascular Endurance Run (PACER laps to One-mile run/walk (1MRW times to estimate aerobic fitness (VO2MAX in children. However, other prediction models can more directly estimate VO2MAX from PACER performance. The purpose of this study was to examine the convergent validity and relative accuracy between 1MRW and various PACER models for predicting VO2MAX in middle school students. Aerobic fitness was assessed on 134 students utilizing the 1MRW and PACER on separate testing days. Pearson correlations, Bland–Altman plots, kappa statistics, proportion of agreement, and prediction error were used to assess associations and agreement among models. Correlation coefficients were strong (r ≥ .80, p .40 and agreement > .90. The results support that PACER models contain convergent validity and strong relative accuracy with the 1MRW model.

  9. On the incremental validity of irrational beliefs to predict subjective well-being while controlling for personality factors.

    Science.gov (United States)

    Spörrle, Matthias; Strobel, Maria; Tumasjan, Andranik

    2010-11-01

    This research examines the incremental validity of irrational thinking as conceptualized by Albert Ellis to predict diverse aspects of subjective well-being while controlling for the influence of personality factors. Rational-emotive behavior therapy (REBT) argues that irrational beliefs result in maladaptive emotions leading to reduced well-being. Although there is some early scientific evidence for this relation, it has never been investigated whether this connection would still persist when statistically controlling for the Big Five personality factors, which were consistently found to be important determinants of well-being. Regression analyses revealed significant incremental validity of irrationality over personality factors when predicting life satisfaction, but not when predicting subjective happiness. Results are discussed with respect to conceptual differences between these two aspects of subjective well-being.

  10. Risk of malignancy in pulmonary nodules: A validation study of four prediction models.

    Science.gov (United States)

    Al-Ameri, Ali; Malhotra, Puneet; Thygesen, Helene; Plant, Paul K; Vaidyanathan, Sri; Karthik, Shishir; Scarsbrook, Andrew; Callister, Matthew E J

    2015-07-01

    Clinical prediction models assess the likelihood of malignancy in pulmonary nodules detected by computed tomography (CT). This study aimed to validate four such models in a UK population of patients with pulmonary nodules. Three models used clinical and CT characteristics to predict risk (Mayo Clinic, Veterans Association, Brock University) with a fourth model (Herder et al. [4]) additionally incorporating (18)Fluorine-Fluorodeoxyglucose (FDG) avidity on positron emission tomography-computed tomography (PET-CT). The likelihood of malignancy was calculated for patients with pulmonary nodules (4-30mm diameter) and data used to calculate the area under the receiver operating characteristic curve (AUC) for each model. The models were used in a restricted cohort of patients based on each model's exclusion criteria and in the total cohort of all patients. Two hundred and forty-four patients were studied, of whom 139 underwent FDG PET-CT. Ninety-nine (40.6%) patients were subsequently confirmed to have malignant nodules (33.2% primary lung cancer, 7.4% metastatic disease). The Mayo and Brock models performed similarly (AUC 0.895 and 0.902 respectively) and both were significantly better than the Veterans Association model (AUC 0.735, p<0.001 and p=0.002 respectively). In patients undergoing FDG PET-CT, the Herder model had significantly higher accuracy than the other three models (AUC 0.924). When the models were tested on all patients in the cohort (i.e. including those outside the original model inclusion criteria) AUC values were reduced, yet remained high especially for the Herder model (AUC 0.916). For sub-centimetre nodules, AUC values for the Mayo and Brock models were 0.788 and 0.852 respectively. The Mayo and Brock models showed good accuracy for determining likelihood of malignancy in nodules detected on CT scan. In patients undergoing FDG PET-CT for nodule evaluation, the highest accuracy was seen for the model described by Herder et al. incorporating FDG

  11. Validating an energy expenditure prediction equation in overweight and obese Mexican patients

    Directory of Open Access Journals (Sweden)

    Gabriela Quiroz-Olguín

    Full Text Available Background: The prevalence of overweight and obesity in Mexico is approximately 70%; thus, obtaining a reliable measurement of the resting energy expenditure (REE in these patients is of extreme importance. The aim of the study was to obtain a prediction equation of REE in overweight or obese outpatients in the Mexican population. Methods: The study was conducted at The National Institute for Medical Sciences and Nutrition Salvador Zubirân (Mexico, D.F.. Consecutive outpatients (18-70 years old at the Clinical Nutrition were evaluated between March 2010 and August 2012 after being diagnosed with overweight or obesity (body mass index [BMI] > 25 kg/m². Patients with any disease that could affect the measurement of gas exchange were excluded. Participants were evaluated by indirect calorimetry (IC, bioelectrical impedance analysis (BIA and anthropometric measurements to design the REE prediction equation. Two groups were evaluated: one group for derivation and another group for validation. The REE was also estimated using the equations of Harris-Benedict, Mifflin St-Jeor, Ireton-Jones, Carrasco, Kleiber and Owen, assessing current weight, ideal weight and adjusted weight. A REE equation was obtained by multiple linear regression based on the evaluated variables, and those that gave the best precision to the model were selected. The real REE and the estimated REE were then compared using Student's t-test. To highlight differences, pairs of measurements were further analyzed using the Bland & Altman plot. Pearson correlation coefficients and coefficients of determination between REE values measured by IC and REE values estimated using various formulas were calculated. Results: A total of 77 patients were included in the derivation group: 38 men (49.4% and 39 women (50.6%. The mean age was 48.5 ± 13.9 years, and the mean BMI was 34.7 ± 5.7 kg/m². A total of 50 participants were included in the validation group: 16 men (32% and 34 women (68%. The

  12. Predictive validation of modeled health technology assessment claims: lessons from NICE.

    Science.gov (United States)

    Belsey, Jonathan

    2015-01-01

    The use of cost-effectiveness modeling to prioritize healthcare spending has become a key foundation of UK government policy. Although the preferred method of evaluation-cost-utility analysis-is not without its critics, it represents a standard approach that can arguably be used to assess relative value for money across a range of disease types and interventions. A key limitation of economic modeling, however, is that its conclusions hinge on the input assumptions, many of which are derived from randomized controlled trials or meta-analyses that cannot be reliably linked to real-world performance of treatments in a broader clinical context. This means that spending decisions are frequently based on artificial constructs that may project costs and benefits that are significantly at odds with those that are achievable in reality. There is a clear agenda to carry out some form of predictive validation for the model claims, in order to assess not only whether the spending decisions made can be justified post hoc, but also to ensure that budgetary expenditure continues to be allocated in the most rational way. To date, however, no timely, effective system to carry out this testing has been implemented, with the consequence that there is little objective evidence as to whether the prioritization decisions made are actually living up to expectations. This article reviews two unfulfilled initiatives that have been carried out in the UK over the past 20 years, each of which had the potential to address this objective, and considers why they failed to deliver the expected outcomes.

  13. HSP70 mediates survival in apoptotic cells-Boolean network prediction and experimental validation.

    Science.gov (United States)

    Vasaikar, Suhas V; Ghosh, Sourish; Narain, Priyam; Basu, Anirban; Gomes, James

    2015-01-01

    Neuronal stress or injury results in the activation of proteins, which regulate the balance between survival and apoptosis. However, the complex mechanism of cell signaling involving cell death and survival, activated in response to cellular stress is not yet completely understood. To bring more clarity about these mechanisms, a Boolean network was constructed that represented the apoptotic pathway in neuronal cells. FasL and neurotrophic growth factor (NGF) were considered as inputs in the absence and presence of heat shock proteins known to shift the balance toward survival by rescuing pro-apoptotic cells. The probabilities of survival, DNA repair and apoptosis as cellular fates, in the presence of either the growth factor or FasL, revealed a survival bias encoded in the network. Boolean predictions tested by measuring the mRNA level of caspase-3, caspase-8, and BAX in neuronal Neuro2a (N2a) cell line with NGF and FasL as external input, showed positive correlation with the observed experimental results for survival and apoptotic states. It was observed that HSP70 contributed more toward rescuing cells from apoptosis in comparison to HSP27, HSP40, and HSP90. Overexpression of HSP70 in N2a transfected cells showed reversal of cellular fate from FasL-induced apoptosis to survival. Further, the pro-survival role of the proteins BCL2, IAP, cFLIP, and NFκB determined by vertex perturbation analysis was experimentally validated through protein inhibition experiments using EM20-25, Embelin and Wedelolactone, which resulted in 1.27-, 1.26-, and 1.46-fold increase in apoptosis of N2a cells. The existence of a one-to-one correspondence between cellular fates and attractor states shows that Boolean networks may be employed with confidence in qualitative analytical studies of biological networks.

  14. A pediatric FOUR score coma scale: interrater reliability and predictive validity.

    Science.gov (United States)

    Czaikowski, Brianna L; Liang, Hong; Stewart, C Todd

    2014-04-01

    The Full Outline of UnResponsiveness (FOUR) Score is a coma scale that consists of four components (eye and motor response, brainstem reflexes, and respiration). It was originally validated among the adult population and recently in a pediatric population. To enhance clinical assessment of pediatric intensive care unit patients, including those intubated and/or sedated, at our children's hospital, we modified the FOUR Score Scale for this population. This modified scale would provide many of the same advantages as the original, such as interrater reliability, simplicity, and elimination of the verbal component that is not compatible with the Glasgow Coma Scale (GCS), creating a more valuable neurological assessment tool for the nursing community. Our goal was to potentially provide greater information than the formally used GCS when assessing critically ill, neurologically impaired patients, including those sedated and/or intubated. Experienced pediatric intensive care unit nurses were trained as "expert raters." Two different nurses assessed each subject using the Pediatric FOUR Score Scale (PFSS), GCS, and Richmond Agitation Sedation Scale at three different time points. Data were compared with the Pediatric Cerebral Performance Category (PCPC) assessed by another nurse. Our hypothesis was that the PFSS and PCPC should highly correlate and the GCS and PCPC should correlate lower. Study results show that the PFSS is excellent for interrater reliability for trained nurse-rater pairs and prediction of poor outcome and in-hospital mortality, under various situations, but there were no statistically significant differences between the PFSS and the GCS. However, the PFSS does have the potential to provide greater neurological assessment in the intubated and/or sedated patient based on the outcomes of our study.

  15. Validation of time-lagged ensemble forecasts relevant for predicting aircraft wake vortices

    Energy Technology Data Exchange (ETDEWEB)

    Dengler, Klaus; Anger, Johanna [DLR, Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Keil, Christian [Ludwig-Maximilians-Univ. Muenchen (Germany). Meteorologisches Inst.

    2011-12-15

    Time-Lagged Ensemble (TLE) forecasts of the high-resolution model COSMO-FRA with a horizontal resolution of 2.8 km, an hourly update cycle and a lead time of six hours are validated against measurements of a Wind-Temperature Radar (WTR) for three cases representing different weather regimes: a frontal passage, a stormy situation and a high pressure system. Forecasts and measurements are available at high temporal resolution every 10 minutes. The present study focuses on parameters relevant for forecasting aircraft wake vortices, namely wind, virtual potential temperature and Turbulent Kinetic Energy (TKE) for altitudes below 1600 m. When compared with a deterministic run started once a day at 00 UTC with a lead time of 24 h a reduction of forecast error in the first two forecast hours is visible for all wind components. For wind speed at low levels around 400 m this reduction is of order 1.7 ms{sup -1} for the 1-hour forecast member and 0.9 ms{sup -1} for the equally weighted ensemble mean depending on weather situation. TLE forecasts of virtual potential temperature show an improvement of about 1 K except for the high pressure system while forecast errors of TKE are reduced in all cases below 900 m. Since no data assimilation is used presently in COSMO-FRA, the improvements of the forecasts are the result of the hourly update cycle which benefits from most recent initial conditions provided by the COSMO-EU analysis. The results of this study may contribute to improve the quality of wake vortex predictions and encourage the assimilation of temporal high resolution wind data into COSMO-FRA to further improve the very short range forecasts. (orig.)

  16. Schmallenberg virus circulation in culicoides in Belgium in 2012: field validation of a real time RT-PCR approach to assess virus replication and dissemination in midges.

    Directory of Open Access Journals (Sweden)

    Nick De Regge

    Full Text Available Indigenous Culicoides biting midges are suggested to be putative vectors for the recently emerged Schmallenberg virus (SBV based on SBV RNA detection in field-caught midges. Furthermore, SBV replication and dissemination has been evidenced in C. sonorensis under laboratory conditions. After SBV had been detected in Culicoides biting midges from Belgium in August 2011, it spread all over the country by the end of 2011, as evidenced by very high between-herd seroprevalence rates in sheep and cattle. This study investigated if a renewed SBV circulation in midges occurred in 2012 in the context of high seroprevalence in the animal host population and evaluated if a recently proposed realtime RT-PCR approach that is meant to allow assessing the vector competence of Culicoides for SBV and bluetongue virus under laboratory conditions was applicable to field-caught midges. Therefore midges caught with 12 OVI traps in four different regions in Belgium between May and November 2012, were morphologically identified, age graded, pooled and tested for the presence of SBV RNA by realtime RT-PCR. The results demonstrate that although no SBV could be detected in nulliparous midges caught in May 2012, a renewed but short lived circulation of SBV in parous midges belonging to the subgenus Avaritia occured in August 2012 at all four regions. The infection prevalence reached up to 2.86% in the south of Belgium, the region where a lower seroprevalence was found at the end of 2011 than in the rest of the country. Furthermore, a frequency analysis of the Ct values obtained for 31 SBV-S segment positive pools of Avaritia midges showed a clear bimodal distribution with peaks of Ct values between 21-24 and 33-36. This closely resembles the laboratory results obtained for SBV infection of C. sonorensis and implicates indigenous midges belonging to the subgenus Avaritia as competent vectors for SBV.

  17. Schmallenberg virus circulation in culicoides in Belgium in 2012: field validation of a real time RT-PCR approach to assess virus replication and dissemination in midges.

    Science.gov (United States)

    De Regge, Nick; Madder, Maxime; Deblauwe, Isra; Losson, Bertrand; Fassotte, Christiane; Demeulemeester, Julie; Smeets, François; Tomme, Marie; Cay, Ann Brigitte

    2014-01-01

    Indigenous Culicoides biting midges are suggested to be putative vectors for the recently emerged Schmallenberg virus (SBV) based on SBV RNA detection in field-caught midges. Furthermore, SBV replication and dissemination has been evidenced in C. sonorensis under laboratory conditions. After SBV had been detected in Culicoides biting midges from Belgium in August 2011, it spread all over the country by the end of 2011, as evidenced by very high between-herd seroprevalence rates in sheep and cattle. This study investigated if a renewed SBV circulation in midges occurred in 2012 in the context of high seroprevalence in the animal host population and evaluated if a recently proposed realtime RT-PCR approach that is meant to allow assessing the vector competence of Culicoides for SBV and bluetongue virus under laboratory conditions was applicable to field-caught midges. Therefore midges caught with 12 OVI traps in four different regions in Belgium between May and November 2012, were morphologically identified, age graded, pooled and tested for the presence of SBV RNA by realtime RT-PCR. The results demonstrate that although no SBV could be detected in nulliparous midges caught in May 2012, a renewed but short lived circulation of SBV in parous midges belonging to the subgenus Avaritia occured in August 2012 at all four regions. The infection prevalence reached up to 2.86% in the south of Belgium, the region where a lower seroprevalence was found at the end of 2011 than in the rest of the country. Furthermore, a frequency analysis of the Ct values obtained for 31 SBV-S segment positive pools of Avaritia midges showed a clear bimodal distribution with peaks of Ct values between 21-24 and 33-36. This closely resembles the laboratory results obtained for SBV infection of C. sonorensis and implicates indigenous midges belonging to the subgenus Avaritia as competent vectors for SBV.

  18. Validation of a new formula for predicting body weight in a Mexican population with overweight and obesity

    Directory of Open Access Journals (Sweden)

    Gabriela Quiroz-Olguín

    2013-06-01

    Full Text Available Introduction: Body weight measurement is of critical importance when evaluating the nutritional status of patients entering a hospital. In some situations, such as the case of patients who are bedridden or in wheelchairs, these measurements cannot be obtained using standardized methods. We have designed and validated a formula for predicting body weight. Objectives: To design and validate a formula for predicting body weight using circumference-based equations. Methods: The following anthropometric measurements were taken for a sample of 76 patients: weight (kg, calf circumference, average arm circumference, waist circumference, hip circumference, wrist circumference and demispan. All circumferences were taken in centimeters (cm, and gender and age were taken into account. This equation was validated in 85 individuals from a different population. The correlation with the new equation was analyzed and compared to a previously validated method. Results: The equation for weight prediction was the following: Weight = 0.524 (WC - 0.176 (age + 0.484 (HC + 0.613 (DS + 0.704 (CC + 2.75 (WrC - 3.330 (if female -140.87. The correlation coefficient was 0.96 for the total group of patients, 0.971 for men and 0.961 for women (p < 0.0001 for all measurements. Conclusion: The equation we developed is accurate and can be used to estimate body weight in overweight and/or obese patients with mobility problems, such as bedridden patients or patients in wheelchairs.

  19. Derivation and Validation of a Novel Prediction Model to Identify Low-Risk Patients With Acute Pulmonary Embolism.

    Science.gov (United States)

    Subramanian, Muthiah; Gopalan, Sowmya; Ramadurai, Srinivasan; Arthur, Preetam; Prabhu, Mukund A; Thachathodiyl, Rajesh; Natarajan, Kumaraswamy

    2017-08-15

    Accurate identification of low-risk patients with acute pulmonary embolism (PE) who may be eligible for outpatient treatment or early discharge can have substantial cost-saving benefit. The purpose of this study was to derive and validate a prediction model to effectively identify patients with PE at low risk of short-term mortality, right ventricular dysfunction, and other nonfatal outcomes. This study analyzed data from 400 consecutive patients with acute PE. We derived and internally validated our prediction rule based on clinically significant variables that are routinely available at initial examination and that were categorized and weighted using coefficients in the multivariate logistic regression. The model was externally validated in an independent cohort of 82 patients. The final model (HOPPE score) consisted of 5 categorized patient variables (1, 2, or 3 points, respectively): systolic blood pressure (>120, 100 to 119, 80, 65 to 79, 101 beats/min), arterial partial pressure of oxygen (>80, 60 to 79, 4). The 30-day mortality rates were 0% in low risk (0 to 6 points), 7.5% to 8.5% in intermediate risk (7 to 10), and 18.2% to 18.8% in high-risk patients (≥11) across the derivation and validation cohorts. In comparison with the previously validated PESI score, the HOPPE score had a higher discriminatory power (area under the curve 0.74 vs 0.85, p = 0.033) and significantly improved both the discrimination (integrated discrimination improvement, p = 0.002) and reclassification (net reclassification improvement, p = 0.003) of the model for short-term mortality. In conclusion, the HOPPE score accurately identifies acute patients with PE at low risk of short-term mortality, right ventricular dysfunction, and other nonfatal outcomes. Prospective validation of the prediction model is necessary before implementation in clinical practice. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. How to develop, validate, and compare clinical prediction models involving radiological parameters: Study design and statistical methods

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kyung Hwa; Choi, Byoung Wook [Dept. of Radiology, and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Song, Ki Jun [Dept. of Biostatistics and Medical Informatics, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2016-06-15

    Clinical prediction models are developed to calculate estimates of the probability of the presence/occurrence or future course of a particular prognostic or diagnostic outcome from multiple clinical or non-clinical parameters. Radiologic imaging techniques are being developed for accurate detection and early diagnosis of disease, which will eventually affect patient outcomes. Hence, results obtained by radiological means, especially diagnostic imaging, are frequently incorporated into a clinical prediction model as important predictive parameters, and the performance of the prediction model may improve in both diagnostic and prognostic settings. This article explains in a conceptual manner the overall process of developing and validating a clinical prediction model involving radiological parameters in relation to the study design and statistical methods. Collection of a raw dataset; selection of an appropriate statistical model; predictor selection; evaluation of model performance using a calibration plot, Hosmer-Lemeshow test and c-index; internal and external validation; comparison of different models using c-index, net reclassification improvement, and integrated discrimination improvement; and a method to create an easy-to-use prediction score system will be addressed. This article may serve as a practical methodological reference for clinical researchers.

  1. Archaeal DNA replication.

    Science.gov (United States)

    Kelman, Lori M; Kelman, Zvi

    2014-01-01

    DNA replication is essential for all life forms. Although the process is fundamentally conserved in the three domains of life, bioinformatic, biochemical, structural, and genetic studies have demonstrated that the process and the proteins involved in archaeal DNA replication are more similar to those in eukaryal DNA replication than in bacterial DNA replication, but have some archaeal-specific features. The archaeal replication system, however, is not monolithic, and there are some differences in the replication process between different species. In this review, the current knowledge of the mechanisms governing DNA replication in Archaea is summarized. The general features of the replication process as well as some of the differences are discussed.

  2. Development and Validation of a Wear Model to Predict Polyethylene Wear in a Total Knee Arthroplasty: A Finite Element Analysis

    Directory of Open Access Journals (Sweden)

    Bernardo Innocenti

    2014-11-01

    Full Text Available Ultra-high molecular weight polyethylene (UHMWPE wear in total knee arthroplasty (TKA components is one of the main reasons of the failure of implants and the consequent necessity of a revision procedure. Experimental wear tests are commonly used to quantify polyethylene wear in an implant, but these procedures are quite expensive and time consuming. On the other hand, numerical models could be used to predict the results of a wear test in less time with less cost. This requires, however, that such a model is not only available, but also validated. Therefore, the aim of this study is to develop and validate a finite element methodology to be used for predicting polyethylene wear in TKAs. Initially, the wear model was calibrated using the results of an experimental roll-on-plane wear test. Afterwards, the developed wear model was applied to predict patello-femoral wear. Finally, the numerical model was validated by comparing the numerically-predicted wear, with experimental results achieving good agreement.

  3. A Multivariate Model for Prediction of Obstructive Coronary Disease in Patients with Acute Chest Pain: Development and Validation

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    Luis Cláudio Lemos Correia

    Full Text Available Abstract Background: Currently, there is no validated multivariate model to predict probability of obstructive coronary disease in patients with acute chest pain. Objective: To develop and validate a multivariate model to predict coronary artery disease (CAD based on variables assessed at admission to the coronary care unit (CCU due to acute chest pain. Methods: A total of 470 patients were studied, 370 utilized as the derivation sample and the subsequent 100 patients as the validation sample. As the reference standard, angiography was required to rule in CAD (stenosis ≥ 70%, while either angiography or a negative noninvasive test could be used to rule it out. As predictors, 13 baseline variables related to medical history, 14 characteristics of chest discomfort, and eight variables from physical examination or laboratory tests were tested. Results: The prevalence of CAD was 48%. By logistic regression, six variables remained independent predictors of CAD: age, male gender, relief with nitrate, signs of heart failure, positive electrocardiogram, and troponin. The area under the curve (AUC of this final model was 0.80 (95% confidence interval [95%CI] = 0.75 - 0.84 in the derivation sample and 0.86 (95%CI = 0.79 - 0.93 in the validation sample. Hosmer-Lemeshow's test indicated good calibration in both samples (p = 0.98 and p = 0.23, respectively. Compared with a basic model containing electrocardiogram and troponin, the full model provided an AUC increment of 0.07 in both derivation (p = 0.0002 and validation (p = 0.039 samples. Integrated discrimination improvement was 0.09 in both derivation (p < 0.001 and validation (p < 0.0015 samples. Conclusion: A multivariate model was derived and validated as an accurate tool for estimating the pretest probability of CAD in patients with acute chest pain.

  4. External validation of a COPD prediction model using population-based primary care data: a nested case-control study

    Science.gov (United States)

    Nwaru, Bright I; Simpson, Colin R; Sheikh, Aziz; Kotz, Daniel

    2017-01-01

    Emerging models for predicting risk of chronic obstructive pulmonary disease (COPD) require external validation in order to assess their clinical value. We validated a previous model for predicting new onset COPD in a different database. We randomly drew 38,597 case-control pairs (total N = 77,194) of individuals aged ≥35 years and matched for sex, age, and general practice from the United Kingdom Clinical Practice Research Datalink database. We assessed accuracy of the model to discriminate between COPD cases and non-cases by calculating area under the receiver operator characteristic (ROCAUC) for the prediction scores. Analogous to the development model, ever smoking (OR 6.70; 95%CI 6.41–6.99), prior asthma (OR 6.43; 95%CI 5.85–7.07), and higher socioeconomic deprivation (OR 2.90; 95%CI 2.72–3.09 for highest vs. lowest quintile) increased the risk of COPD. The validated prediction scores ranged from 0–5.71 (ROCAUC 0.66; 95%CI 0.65–0.66) for males and 0–5.95 (ROCAUC 0.71; 95%CI 0.70–0.71) for females. We have confirmed that smoking, prior asthma, and socioeconomic deprivation are key risk factors for new onset COPD. Our model seems externally valid at identifying patients at risk of developing COPD. An impact assessment now needs to be undertaken to assess whether this prediction model can be applied in clinical care settings. PMID:28304375

  5. Age-correction of test scores reduces the validity of mild cognitive impairment in predicting progression to dementia.

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    Johannes Hessler

    Full Text Available A phase of mild cognitive impairment (MCI precedes most forms of neurodegenerative dementia. Many definitions of MCI recommend the use of test norms to diagnose cognitive impairment. It is, however, unclear whether the use of norms actually improves the detection of individuals at risk of dementia. Therefore, the effects of age- and education-norms on the validity of test scores in predicting progression to dementia were investigated.Baseline cognitive test scores (Syndrome Short Test of dementia-free participants aged ≥65 were used to predict progression to dementia within three years. Participants were comprehensively examined one, two, and three years after baseline. Test scores were calculated with correction for (1 age and education, (2 education only, (3 age only and (4 without correction. Predictive validity was estimated with Cox proportional hazard regressions. Areas under the curve (AUCs were calculated for the one-, two-, and three-year intervals.82 (15.3% of initially 537 participants, developed dementia. Model coefficients, hazard ratios, and AUCs of all scores were significant (p<0.001. Predictive validity was the lowest with age-corrected scores (-2 log likelihood  = 840.90, model fit χ2 (1  = 144.27, HR  = 1.33, AUCs between 0.73 and 0.87 and the highest with education-corrected scores (-2 log likelihood  = 815.80, model fit χ2 (1  = 171.16, HR  = 1.34, AUCs between 0.85 and 0.88.The predictive validity of test scores is markedly reduced by age-correction. Therefore, definitions of MCI should not recommend the use of age-norms in order to improve the detection of individuals at risk of dementia.

  6. Nucleotide Metabolism and DNA Replication.

    Science.gov (United States)

    Warner, Digby F; Evans, Joanna C; Mizrahi, Valerie

    2014-10-01

    The development and application of a highly versatile suite of tools for mycobacterial genetics, coupled with widespread use of "omics" approaches to elucidate the structure, function, and regulation of mycobacterial proteins, has led to spectacular advances in our understanding of the metabolism and physiology of mycobacteria. In this article, we provide an update on nucleotide metabolism and DNA replication in mycobacteria, highlighting key findings from the past 10 to 15 years. In the first section, we focus on nucleotide metabolism, ranging from the biosynthesis, salvage, and interconversion of purine and pyrimidine ribonucleotides to the formation of deoxyribonucleotides. The second part of the article is devoted to DNA replication, with a focus on replication initiation and elongation, as well as DNA unwinding. We provide an overview of replication fidelity and mutation rates in mycobacteria and summarize evidence suggesting that DNA replication occurs during states of low metabolic activity, and conclude by suggesting directions for future research to address key outstanding questions. Although this article focuses primarily on observations from Mycobacterium tuberculosis, it is interspersed, where appropriate, with insights from, and comparisons with, other mycobacterial species as well as better characterized bacterial models such as Escherichia coli. Finally, a common theme underlying almost all studies of mycobacterial metabolism is the potential to identify and validate functions or pathways that can be exploited for tuberculosis drug discovery. In this context, we have specifically highlighted those processes in mycobacterial DNA replication that might satisfy this critical requirement.

  7. Validation of a predictive model for smart control of electrical energy storage

    NARCIS (Netherlands)

    Homan, Bart; Leeuwen, van Richard P.; Smit, Gerard J.M.; Zhu, Lei; Wit, de Jan B.

    2016-01-01

    The purpose of this paper is to investigate the applicability of a relatively simple model which is based on energy conservation for model predictions as part of smart control of thermal and electric storage. The paper reviews commonly used predictive models. Model predictions of charging and discha

  8. Validity of Outcome Prediction Scoring Systems in Korean Patients with Severe Adult Respiratory Distress Syndrome Receiving Extracorporeal Membrane Oxygenation Therapy.

    Science.gov (United States)

    Lee, Seunghyun; Yeo, Hye Ju; Yoon, Seong Hoon; Lee, Seung Eun; Cho, Woo Hyun; Jeon, Doo Soo; Kim, Yun Seong; Son, Bong Soo; Kim, Do Hyung

    2016-06-01

    Recently, several prognostic scoring systems for patients with severe acute respiratory distress syndrome (ARDS) requiring extracorporeal membrane oxygenation (ECMO) have been published. The aim of this study was to validate the established scoring systems for outcome prediction in Korean patients. We retrospectively reviewed the data of 50 patients on ECMO therapy in our center from 2012 to 2014. A calculation of outcome prediction scoring tools was performed and the comparison across various models was conducted. In our study, the overall hospital survival was 46% and successful weaning rate was 58%. The Predicting Death for Severe ARDS on V-V ECMO (PRESERVE) score showed good discrimination of mortality prediction for patients on ECMO with AUC of 0.80 (95% CI 0.66-0.90). The respiratory extracorporeal membrane oxygenation survival prediction (RESP) score and simplified acute physiology score (SAPS) II score also showed fair prediction ability with AUC of 0.79 (95% CI 0.65-0.89) and AUC of 0.78 (95% CI 0.64-0.88), respectively. However, the ECMOnet score failed to predict mortality with AUC of 0.51 (95% CI 0.37-0.66). When evaluating the predictive accuracy according to optimal cut-off point of each scoring system, RESP score had a best specificity of 91.3% and 66.7% of sensitivity, respectively. This study supports the clinical usefulness of the prognostic scoring tools for severe ARDS with ECMO therapy when applying to the Korean patients receiving ECMO.

  9. Validation of a Prediction Model for Vaginal Birth after Cesarean Delivery Reveals Unexpected Success in a Diverse American Population.

    Science.gov (United States)

    Maykin, Melanie Mai; Mularz, Amanda J; Lee, Lydia K; Valderramos, Stephanie Gaw

    2017-01-01

    Objective To investigate the validity of a prediction model for success of vaginal birth after cesarean delivery (VBAC) in an ethnically diverse population. Methods We performed a retrospective cohort study of women admitted at a single academic institution for a trial of labor after cesarean from May 2007 to January 2015. Individual predicted success rates were calculated using the Maternal-Fetal Medicine Units Network prediction model. Participants were stratified into three probability-of-success groups: low (65%). The actual versus predicted success rates were compared. Results In total, 568 women met inclusion criteria. Successful VBAC occurred in 402 (71%), compared with a predicted success rate of 66% (p = 0.016). Actual VBAC success rates were higher than predicted by the model in the low (57 vs. 29%; p success rate was above 65%, the model was highly accurate. In contrast, for women with predicted success rates <35%, actual VBAC rates were nearly twofold higher in our population, suggesting that they should not be discouraged by a low prediction score.

  10. Validation of a Previously Developed Geospatial Model That Predicts the Prevalence of Listeria monocytogenes in New York State Produce Fields

    Science.gov (United States)

    Weller, Daniel; Shiwakoti, Suvash; Bergholz, Peter; Grohn, Yrjo; Wiedmann, Martin

    2015-01-01

    Technological advancements, particularly in the field of geographic information systems (GIS), have made it possible to predict the likelihood of foodborne pathogen contamination in produce production environments using geospatial models. Yet, few studies have examined the validity and robustness of such models. This study was performed to test and refine the rules associated with a previously developed geospatial model that predicts the prevalence of Listeria monocytogenes in produce farms in New York State (NYS). Produce fields for each of four enrolled produce farms were categorized into areas of high or low predicted L. monocytogenes prevalence using rules based on a field's available water storage (AWS) and its proximity to water, impervious cover, and pastures. Drag swabs (n = 1,056) were collected from plots assigned to each risk category. Logistic regression, which tested the ability of each rule to accurately predict the prevalence of L. monocytogenes, validated the rules based on water and pasture. Samples collected near water (odds ratio [OR], 3.0) and pasture (OR, 2.9) showed a significantly increased likelihood of L. monocytogenes isolation compared to that for samples collected far from water and pasture. Generalized linear mixed models identified additional land cover factors associated with an increased likelihood of L. monocytogenes isolation, such as proximity to wetlands. These findings validated a subset of previously developed rules that predict L. monocytogenes prevalence in produce production environments. This suggests that GIS and geospatial models can be used to accurately predict L. monocytogenes prevalence on farms and can be used prospectively to minimize the risk of preharvest contamination of produce. PMID:26590280

  11. Validation of the diagnoses of panic disorder and phobic disorders in the US National Comorbidity Survey Replication Adolescent (NCS-A) supplement.

    Science.gov (United States)

    Green, Jennifer Greif; Avenevoli, Shelli; Finkelman, Matthew; Gruber, Michael J; Kessler, Ronald C; Merikangas, Kathleen R; Sampson, Nancy A; Zaslavsky, Alan M

    2011-06-01

    Validity of the adolescent version of the World Health Organization Composite International Diagnostic Interview (CIDI) Version 3.0, a fully-structured research diagnostic interview designed to be used by trained lay interviewers, is assessed in comparison to independent clinical diagnoses based on the Schedule for Affective Disorders and Schizophrenia for School-age Children (K-SADS). This assessment is carried out in the clinical reappraisal sub-sample (n = 347) of the US National Comorbidity Survey Adolescent (NCS-A) supplement, a large (n = 10,148) community epidemiological survey of the prevalence and correlates of adolescent mental disorders in the United States. The diagnoses considered are panic disorder and phobic disorders (social phobia, specific phobia, agoraphobia). CIDI diagnoses are found to have good concordance with K-SADS diagnoses [area under the receiver operating characteristic curve (AUC) = 0.81-0.94], although the CIDI diagnoses are consistency somewhat higher than the K-SADS diagnoses. Data are also presented on criterion-level concordance in an effort to pinpoint CIDI question series that might be improved in future modifications of the instrument. Finally, data are presented on the factor structure of the fears associated with social phobia, the only disorder in this series where substantial controversy exists about disorder subtypes. Copyright © 2011 John Wiley & Sons, Ltd.

  12. Validation of adult height prediction based on automated bone age determination in the Paris Longitudinal Study of healthy children

    Energy Technology Data Exchange (ETDEWEB)

    Martin, David D. [Tuebingen University Children' s Hospital, Tuebingen (Germany); Filderklinik, Filderstadt (Germany); Schittenhelm, Jan [Tuebingen University Children' s Hospital, Tuebingen (Germany); Thodberg, Hans Henrik [Visiana, Holte (Denmark)

    2016-02-15

    An adult height prediction model based on automated determination of bone age was developed and validated in two studies from Zurich, Switzerland. Varied living conditions and genetic backgrounds might make the model less accurate. To validate the adult height prediction model on children from another geographical location. We included 51 boys and 58 girls from the Paris Longitudinal Study of children born 1953 to 1958. Radiographs were obtained once or twice a year in these children from birth to age 18. Bone age was determined using the BoneXpert method. Radiographs in children with bone age greater than 6 years were considered, in total 1,124 images. The root mean square deviation between the predicted and the observed adult height was 2.8 cm for boys in the bone age range 6-15 years and 3.1 cm for girls in the bone age range 6-13 years. The bias (the average signed difference) was zero, except for girls below bone age 12, where the predictions were 0.8 cm too low. The accuracy of the BoneXpert method in terms of root mean square error was as predicted by the model, i.e. in line with what was observed in the Zurich studies. (orig.)

  13. Development and Validation of a Multivariable Prediction Model for the Occurrence of Delirium in Hospitalized Gerontopsychiatry and Internal Medicine Patients.

    Science.gov (United States)

    Kramer, Diether; Veeranki, Sai; Hayn, Dieter; Quehenberger, Franz; Leodolter, Werner; Jagsch, Christian; Schreier, Günter

    2017-01-01

    Delirium is an acute confusion condition, which is common in elderly and often misdiagnosed in hospitalized patients. Early identification and prevention of delirium could reduce morbidity and mortality rates in those affected and reduce hospitalization costs. We have developed and validated a multivariate prediction model that predicts delirium and gives an early warning to physicians. A large set of patient electronic medical records have been used in developing the models. Classical learning algorithms have been used to develop the models and compared the results. Excellent results were obtained with the feature set and parameter settings attaining accuracy of 84%.

  14. Reading the Road Signs: The Utility of the MMPI-2 Restructured Form Validity Scales in Prediction of Premature Termination.

    Science.gov (United States)

    Anestis, Joye C; Finn, Jacob A; Gottfried, Emily; Arbisi, Paul A; Joiner, Thomas E

    2015-06-01

    This study examined the utility of the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF) Validity Scales in prediction of premature termination in a sample of 511 individuals seeking services from a university-based psychology clinic. Higher scores on True Response Inconsistency-Revised and Infrequent Psychopathology Responses increased the risk of premature termination, whereas higher scores on Adjustment Validity lowered the risk of premature termination. Additionally, when compared with individuals who did not prematurely terminate, individuals who prematurely terminated treatment had lower Global Assessment of Functioning scores at both intake and termination and made fewer improvements. Implications of these findings for the use of the MMPI-2-RF Validity Scales in promoting treatment compliance are discussed. © The Author(s) 2014.

  15. Validation of a Dutch risk score predicting poor outcome in adults with bacterial meningitis in Vietnam and Malawi.

    Directory of Open Access Journals (Sweden)

    Ewout S Schut

    Full Text Available We have previously developed and validated a prognostic model to predict the risk for unfavorable outcome in Dutch adults with bacterial meningitis. The aim of the current study was to validate this model in adults with bacterial meningitis from two developing countries, Vietnam and Malawi. Demographic and clinical characteristics of Vietnamese (n = 426, Malawian patients (n = 465 differed substantially from those of Dutch patients (n = 696. The Dutch model underestimated the risk of poor outcome in both Malawi and Vietnam. The discrimination of the original model (c-statistic [c] 0.84; 95% confidence interval 0.81 to 0.86 fell considerably when re-estimated in the Vietnam cohort (c = 0.70 or in the Malawian cohort (c = 0.68. Our validation study shows that new prognostic models have to be developed for these countries in a sufficiently large series of unselected patients.

  16. Construction, internal validation and implementation in a mobile application of a scoring system to predict nonadherence to proton pump inhibitors

    Directory of Open Access Journals (Sweden)

    Emma Mares-García

    2017-06-01

    Full Text Available Background Other studies have assessed nonadherence to proton pump inhibitors (PPIs, but none has developed a screening test for its detection. Objectives To construct and internally validate a predictive model for nonadherence to PPIs. Methods This prospective observational study with a one-month follow-up was carried out in 2013 in Spain, and included 302 patients with a prescription for PPIs. The primary variable was nonadherence to PPIs (pill count. Secondary variables were gender, age, antidepressants, type of PPI, non-guideline-recommended prescription (NGRP of PPIs, and total number of drugs. With the secondary variables, a binary logistic regression model to predict nonadherence was constructed and adapted to a points system. The ROC curve, with its area (AUC, was calculated and the optimal cut-off point was established. The points system was internally validated through 1,000 bootstrap samples and implemented in a mobile application (Android. Results The points system had three prognostic variables: total number of drugs, NGRP of PPIs, and antidepressants. The AUC was 0.87 (95% CI [0.83–0.91], p < 0.001. The test yielded a sensitivity of 0.80 (95% CI [0.70–0.87] and a specificity of 0.82 (95% CI [0.76–0.87]. The three parameters were very similar in the bootstrap validation. Conclusions A points system to predict nonadherence to PPIs has been constructed, internally validated and implemented in a mobile application. Provided similar results are obtained in external validation studies, we will have a screening tool to detect nonadherence to PPIs.

  17. First-trimester prediction of pre-eclampsia: external validity of algorithms in a prospectively enrolled cohort.

    Science.gov (United States)

    Oliveira, N; Magder, L S; Blitzer, M G; Baschat, A A

    2014-09-01

    To evaluate the performance of published first-trimester prediction algorithms for pre-eclampsia (PE) in a prospectively enrolled cohort of women. A MEDLINE search identified first-trimester screening-prediction algorithms for early-onset (requiring delivery algorithms were applied to this population to calculate predicted probabilities for PE. The performance of the prediction algorithms was compared with that in the original publication and evaluated for factors explaining differences in prediction. Six early and two late PE prediction algorithms were applicable to 871-2962 women, depending on the variables required. The prevalence of early PE was 1.0-1.2% and of late PE was 4.1-5.0% in these patient subsets. One early PE prediction algorithm performed better than in the original publication (80% detection rate (DR) of early PE for 10% false-positive rate (FPR)); the remaining five prediction algorithms underperformed (29-53% DR). Prediction algorithms for late PE also underperformed (18-31% DR, 10% FPR). Applying the screening cut-offs based on the highest Youden index probability scores correctly detected 40-80% of women developing early PE and 71-82% who developed late PE. Exclusion of patients on first-trimester aspirin resulted in DRs of 40-83% and 65-82% for early and late PE, respectively. First-trimester prediction algorithms for PE share a high negative predictive value if applied to an external population but underperform in their ability to correctly identify women who develop PE. Further research is required to determine the factors responsible for the suboptimal external validity. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

  18. Predictive Validity of Non-g Residuals of Tests: More Than g

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    Thomas R. Coyle

    2014-03-01

    Full Text Available This comment argues that an important issue in intelligence research is to identify constructs with validity beyond g, and that non-g residuals of tests represent a promising target.

  19. Prediction of dissolved reactive phosphorus losses from small agricultural catchments: calibration and validation of a parsimonious model

    Directory of Open Access Journals (Sweden)

    C. Hahn

    2013-10-01

    Full Text Available Eutrophication of surface waters due to diffuse phosphorus (P losses continues to be a severe water quality problem worldwide, causing the loss of ecosystem functions of the respective water bodies. Phosphorus in runoff often originates from a small fraction of a catchment only. Targeting mitigation measures to these critical source areas (CSAs is expected to be most efficient and cost-effective, but requires suitable tools. Here we investigated the capability of the parsimonious Rainfall-Runoff-Phosphorus (RRP model to identify CSAs in grassland-dominated catchments based on readily available soil and topographic data. After simultaneous calibration on runoff data from four small hilly catchments on the Swiss Plateau, the model was validated on a different catchment in the same region without further calibration. The RRP model adequately simulated the discharge and dissolved reactive P (DRP export from the validation catchment. Sensitivity analysis showed that the model predictions were robust with respect to the classification of soils into "poorly drained" and "well drained", based on the available soil map. Comparing spatial hydrological model predictions with field data from the validation catchment provided further evidence that the assumptions underlying the model are valid and that the model adequately accounts for the dominant P export processes in the target region. Thus, the parsimonious RRP model is a valuable tool that can be used to determine CSAs. Despite the considerable predictive uncertainty regarding the spatial extent of CSAs, the RRP can provide guidance for the implementation of mitigation measures. The model helps to identify those parts of a catchment where high DRP losses are expected or can be excluded with high confidence. Legacy P was predicted to be the dominant source for DRP losses and thus, in combination with hydrologic active areas, a high risk for water quality.

  20. Failure to Validate a Multivariable Clinical Prediction Model to Identify Pediatric Intensive Care Unit Patients at High Risk for Candidemia.

    Science.gov (United States)

    Fisher, Brian T; Ross, Rachael K; Roilides, Emmanuel; Palazzi, Debra L; Abzug, Mark J; Hoffman, Jill A; Berman, David M; Prasad, Priya A; Localio, A Russell; Steinbach, William J; Vogiatzi, Lambrini; Dutta, Ankhi; Zaoutis, Theoklis E

    2016-12-01

    We attempted to validate a previously derived clinical prediction rule for candidemia in the pediatric intensive care unit. This multicenter case control study did not identify significant association of candidemia with most of the previously identified predictors. Additional study in larger cohorts with other predictor variables is needed. © The Author 2015. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. The validity of Iran’s national university entrance examination (Konkoor) for predicting medical students’ academic performance

    OpenAIRE

    Farrokhi-Khajeh-Pasha Yasin; Nedjat Saharnaz; Mohammadi Aeen; Rad Elaheh; Majdzadeh Reza; Monajemi Farshid; Jamali Ehsan; Yazdani Shahryar

    2012-01-01

    Abstract Background In Iran, admission to medical school is based solely on the results of the highly competitive, nationwide Konkoor examination. This paper examines the predictive validity of Konkoor scores, alone and in combination with high school grade point averages (hsGPAs), for the academic performance of public medical school students in Iran. Methods This study followed the cohort of 2003 matriculants at public medical schools in Iran from entrance through internship. The predictor ...

  2. Validity of resting energy expenditure predictive equations before and after an energy-restricted diet intervention in obese women.

    Directory of Open Access Journals (Sweden)

    Jonatan R Ruiz

    Full Text Available BACKGROUND: We investigated the validity of REE predictive equations before and after 12-week energy-restricted diet intervention in Spanish obese (30 kg/m(2>BMI<40 kg/m(2 women. METHODS: We measured REE (indirect calorimetry, body weight, height, and fat mass (FM and fat free mass (FFM, dual X-ray absorptiometry in 86 obese Caucasian premenopausal women aged 36.7±7.2 y, before and after (n = 78 women the intervention. We investigated the accuracy of ten REE predictive equations using weight, height, age, FFM and FM. RESULTS: At baseline, the most accurate equation was the Mifflin et al. (Am J Clin Nutr 1990; 51: 241-247 when using weight (bias:-0.2%, P = 0.982, 74% of accurate predictions. This level of accuracy was not reached after the diet intervention (24% accurate prediction. After the intervention, the lowest bias was found with the Owen et al. (Am J Clin Nutr 1986; 44: 1-19 equation when using weight (bias:-1.7%, P = 0.044, 81% accurate prediction, yet it provided 53% accurate predictions at baseline. CONCLUSIONS: There is a wide variation in the accuracy of REE predictive equations before and after weight loss in non-morbid obese women. The results acquire especial relevance in the context of the challenging weight regain phenomenon for the overweight/obese population.

  3. Autonomy and control: augmenting the validity of the theory of planned behaviour in predicting exercise.

    Science.gov (United States)

    Brickell, Tracey A; Chatzisarantis, Nikos L D; Pretty, Grace M

    2006-01-01

    This study examined the utility of the theory of planned behaviour (TPB) along with additional constructs in predicting exercise, and explored the motivational antecedents of exercise intentions. Participants included 162 Canadian University College students (61% females). Measures of TPB, autonomous and controlling intention, perceived autonomy support and core autonomous intention were completed during phase 1 of data collection. Two and three weeks later behaviour was assessed. Hierarchical regression analyses revealed that: (a) attitude and perceived behavioural control significantly predicted TPB intention and core autonomous intention; (b) subjective norm predicted controlling intention; and (c) perceived autonomy support predicted autonomous and core autonomous intention. TPB intention significantly predicted behaviour. TPB is a fairly useful model for predicting behaviour and important information can be gained when other measures of intention are explored.

  4. Benchmarking mutation effect prediction algorithms using functionally validated cancer-related missense mutations.

    Science.gov (United States)

    Martelotto, Luciano G; Ng, Charlotte Ky; De Filippo, Maria R; Zhang, Yan; Piscuoglio, Salvatore; Lim, Raymond S; Shen, Ronglai; Norton, Larry; Reis-Filho, Jorge S; Weigelt, Britta

    2014-10-28

    Massively parallel sequencing studies have led to the identification of a large number of mutations present in a minority of cancers of a given site. Hence, methods to identify the likely pathogenic mutations that are worth exploring experimentally and clinically are required. We sought to compare the performance of 15 mutation effect prediction algorithms and their agreement. As a hypothesis-generating aim, we sought to define whether combinations of prediction algorithms would improve the functional effect predictions of specific mutations. Literature and database mining of single nucleotide variants (SNVs) affecting 15 cancer genes was performed to identify mutations supported by functional evidence or hereditary disease association to be classified either as non-neutral (n = 849) or neutral (n = 140) with respect to their impact on protein function. These SNVs were employed to test the performance of 15 mutation effect prediction algorithms. The accuracy of the prediction algorithms varies considerably. Although all algorithms perform consistently well in terms of positive predictive value, their negative predictive value varies substantially. Cancer-specific mutation effect predictors display no-to-almost perfect agreement in their predictions of these SNVs, whereas the non-cancer-specific predictors showed no-to-moderate agreement. Combinations of predictors modestly improve accuracy and significantly improve negative predictive values. The information provided by mutation effect predictors is not equivalent. No algorithm is able to predict sufficiently accurately SNVs that should be taken forward for experimental or clinical testing. Combining algorithms aggregates orthogonal information and may result in improvements in the negative predictive value of mutation effect predictions.

  5. Development of Prediction Model and Experimental Validation in Predicting the Curcumin Content of Turmeric (Curcuma longa L.)

    Science.gov (United States)

    Akbar, Abdul; Kuanar, Ananya; Joshi, Raj K.; Sandeep, I. S.; Mohanty, Sujata; Naik, Pradeep K.; Mishra, Antaryami; Nayak, Sanghamitra

    2016-01-01

    The drug yielding potential of turmeric (Curcuma longa L.) is largely due to the presence of phyto-constituent ‘curcumin.’ Curcumin has been found to possess a myriad of therapeutic activities ranging from anti-inflammatory to neuroprotective. Lack of requisite high curcumin containing genotypes and variation in the curcumin content of turmeric at different agro climatic regions are the major stumbling blocks in commercial production of turmeric. Curcumin content of turmeric is greatly influenced by environmental factors. Hence, a prediction model based on artificial neural network (ANN) was developed to map genome environment interaction basing on curcumin content, soli and climatic factors from different agroclimatic regions for prediction of maximum curcumin content at various sites to facilitate the selection of suitable region for commercial cultivation of turmeric. The ANN model was developed and tested using a data set of 119 generated by collecting samples from 8 different agroclimatic regions of Odisha. The curcumin content from these samples was measured that varied from 7.2% to 0.4%. The ANN model was trained with 11 parameters of soil and climatic factors as input and curcumin content as output. The results showed that feed-forward ANN model with 8 nodes (MLFN-8) was the most suitable one with R2 value of 0.91. Sensitivity analysis revealed that minimum relative humidity, altitude, soil nitrogen content and soil pH had greater effect on curcumin content. This ANN model has shown proven efficiency for predicting and optimizing the curcumin content at a specific site. PMID:27766103

  6. Development of Prediction Model and Experimental Validation in Predicting the Curcumin Content of Turmeric (Curcuma longa L.).

    Science.gov (United States)

    Akbar, Abdul; Kuanar, Ananya; Joshi, Raj K; Sandeep, I S; Mohanty, Sujata; Naik, Pradeep K; Mishra, Antaryami; Nayak, Sanghamitra

    2016-01-01

    The drug yielding potential of turmeric (Curcuma longa L.) is largely due to the presence of phyto-constituent 'curcumin.' Curcumin has been found to possess a myriad of therapeutic activities ranging from anti-inflammatory to neuroprotective. Lack of requisite high curcumin containing genotypes and variation in the curcumin content of turmeric at different agro climatic regions are the major stumbling blocks in commercial production of turmeric. Curcumin content of turmeric is greatly influenced by environmental factors. Hence, a prediction model based on artificial neural network (ANN) was developed to map genome environment interaction basing on curcumin content, soli and climatic factors from different agroclimatic regions for prediction of maximum curcumin content at various sites to facilitate the selection of suitable region for commercial cultivation of turmeric. The ANN model was developed and tested using a data set of 119 generated by collecting samples from 8 different agroclimatic regions of Odisha. The curcumin content from these samples was measured that varied from 7.2% to 0.4%. The ANN model was trained with 11 parameters of soil and climatic factors as input and curcumin content as output. The results showed that feed-forward ANN model with 8 nodes (MLFN-8) was the most suitable one with R(2) value of 0.91. Sensitivity analysis revealed that minimum relative humidity, altitude, soil nitrogen content and soil pH had greater effect on curcumin content. This ANN model has shown proven efficiency for predicting and optimizing the curcumin content at a specific site.

  7. Computerized prediction of intensive care unit discharge after cardiac surgery: development and validation of a Gaussian processes model.

    Science.gov (United States)

    Meyfroidt, Geert; Güiza, Fabian; Cottem, Dominiek; De Becker, Wilfried; Van Loon, Kristien; Aerts, Jean-Marie; Berckmans, Daniël; Ramon, Jan; Bruynooghe, Maurice; Van den Berghe, Greet

    2011-10-25

    The intensive care unit (ICU) length of stay (LOS) of patients undergoing cardiac surgery may vary considerably, and is often difficult to predict within the first hours after admission. The early clinical evolution of a cardiac surgery patient might be predictive for his LOS. The purpose of the present study was to develop a predictive model for ICU discharge after non-emergency cardiac surgery, by analyzing the first 4 hours of data in the computerized medical record of these patients with Gaussian processes (GP), a machine learning technique. Non-interventional study. Predictive modeling, separate development (n = 461) and validation (n = 499) cohort. GP models were developed to predict the probability of ICU discharge the day after surgery (classification task), and to predict the day of ICU discharge as a discrete variable (regression task). GP predictions were compared with predictions by EuroSCORE, nurses and physicians. The classification task was evaluated using aROC for discrimination, and Brier Score, Brier Score Scaled, and Hosmer-Lemeshow test for calibration. The regression task was evaluated by comparing median actual and predicted discharge, loss penalty function (LPF) ((actual-predicted)/actual) and calculating root mean squared relative errors (RMSRE). Median (P25-P75) ICU length of stay was 3 (2-5) days. For classification, the GP model showed an aROC of 0.758 which was significantly higher than the predictions by nurses, but not better than EuroSCORE and physicians. The GP had the best calibration, with a Brier Score of 0.179 and Hosmer-Lemeshow p-value of 0.382. For regression, GP had the highest proportion of patients with a correctly predicted day of discharge (40%), which was significantly better than the EuroSCORE (p nurses (p = 0.044) but equivalent to physicians. GP had the lowest RMSRE (0.408) of all predictive models. A GP model that uses PDMS data of the first 4 hours after admission in the ICU of scheduled adult cardiac surgery

  8. Biased binomial assessment of cross-validated estimation of classification accuracies illustrated in diagnosis predictions

    Directory of Open Access Journals (Sweden)

    Quentin Noirhomme

    2014-01-01

    Full Text Available Multivariate classification is used in neuroimaging studies to infer brain activation or in medical applications to infer diagnosis. Their results are often assessed through either a binomial or a permutation test. Here, we simulated classification results of generated random data to assess the influence of the cross-validation scheme on the significance of results. Distributions built from classification of random data with cross-validation did not follow the binomial distribution. The binomial test is therefore not adapted. On the contrary, the permutation test was unaffected by the cross-validation scheme. The influence of the cross-validation was further illustrated on real-data from a brain–computer interface experiment in patients with disorders of consciousness and from an fMRI study on patients with Parkinson disease. Three out of 16 patients with disorders of consciousness had significant accuracy on binomial testing, but only one showed significant accuracy using permutation testing. In the fMRI experiment, the mental imagery of gait could discriminate significantly between idiopathic Parkinson's disease patients and healthy subjects according to the permutation test but not according to the binomial test. Hence, binomial testing could lead to biased estimation of significance and false positive or negative results. In our view, permutation testing is thus recommended for clinical application of classification with cross-validation.

  9. Biased binomial assessment of cross-validated estimation of classification accuracies illustrated in diagnosis predictions.

    Science.gov (United States)

    Noirhomme, Quentin; Lesenfants, Damien; Gomez, Francisco; Soddu, Andrea; Schrouff, Jessica; Garraux, Gaëtan; Luxen, André; Phillips, Christophe; Laureys, Steven

    2014-01-01

    Multivariate classification is used in neuroimaging studies to infer brain activation or in medical applications to infer diagnosis. Their results are often assessed through either a binomial or a permutation test. Here, we simulated classification results of generated random data to assess the influence of the cross-validation scheme on the significance of results. Distributions built from classification of random data with cross-validation did not follow the binomial distribution. The binomial test is therefore not adapted. On the contrary, the permutation test was unaffected by the cross-validation scheme. The influence of the cross-validation was further illustrated on real-data from a brain-computer interface experiment in patients with disorders of consciousness and from an fMRI study on patients with Parkinson disease. Three out of 16 patients with disorders of consciousness had significant accuracy on binomial testing, but only one showed significant accuracy using permutation testing. In the fMRI experiment, the mental imagery of gait could discriminate significantly between idiopathic Parkinson's disease patients and healthy subjects according to the permutation test but not according to the binomial test. Hence, binomial testing could lead to biased estimation of significance and false positive or negative results. In our view, permutation testing is thus recommended for clinical application of classification with cross-validation.

  10. Development and validation of nomograms to provide individualised predictions of seizure outcomes after epilepsy surgery: a retrospective analysis.

    Science.gov (United States)

    Jehi, Lara; Yardi, Ruta; Chagin, Kevin; Tassi, Laura; Russo, Giorgio Lo; Worrell, Gregory; Hu, Wei; Cendes, Fernando; Morita, Marcia; Bartolomei, Fabrice; Chauvel, Patrick; Najm, Imad; Gonzalez-Martinez, Jorge; Bingaman, William; Kattan, Michael W

    2015-03-01

    Half of patients who have resective brain surgery for drug-resistant epilepsy have recurrent postoperative seizures. Although several single predictors of seizure outcome have been identified, no validated method incorporates a patient's complex clinical characteristics into an instrument to predict an individual's post-surgery seizure outcome. We developed nomograms to predict complete freedom from seizures and Engel score of 1 (eventual freedom from seizures allowing for some initial postoperative seizures, or seizures occurring only with physiological stress such as drug withdrawal) at 2 years and 5 years after surgery on the basis of sex, seizure frequency, secondary seizure generalisation, type of surgery, pathological cause, age at epilepsy onset, age at surgery, epilepsy duration at time of surgery, and surgical side. We designed the models from a development cohort of patients who had resective surgery at the Cleveland Clinic (Cleveland, OH, USA) between 1996 and 2011. We then tested the nomograms in an external validation cohort operated on over a similar period in four epilepsy surgery centres, in Brazil, France, Italy, and the USA. We assessed performance of the nomogram by calculating concordance statistics and assessing the calibration of predicted freedom from seizures with the reported freedom from seizures and Engel score of 1. The development cohort included 846 patients and the validation cohort included 604 patients. Variables included in the nomograms were sex, seizure frequency, secondary seizure generalisation, type of surgery, and pathological cause. In the development cohort, the baseline risk of complete freedom from seizures was 0·57 at 2 years and 0·40 at 5 years. The baseline risk of Engel score of 1 was 0·69 at 2 years and 0·62 at 5 years. In the validation cohort, the models had a concordance statistic of 0·60 for complete freedom from seizures and 0·61 for Engel score of 1. Calibration curves showed adequate calibration (judged

  11. Predictive Accuracy of the PanCan Lung Cancer Risk Prediction Model -External Validation based on CT from the Danish Lung Cancer Screening Trial

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde M.; van Riel, Sarah J.; Saghir, Zaigham

    2015-01-01

    ; in fact opposing effects of sex were observed in the two cohorts. Thus, female sex appeared to lower the risk (p = 0.047 and p = 0.040) in the DLCST. Conclusions: High risk discrimination was validated in the DLCST cohort, mainly determined by nodule size. Age and family history of lung cancer were......Objectives: Lung cancer risk models should be externally validated to test generalizability and clinical usefulness. The Danish Lung Cancer Screening Trial (DLCST) is a population-based prospective cohort study, used to assess the discriminative performances of the PanCan models. Methods: From...... used to evaluate risk discrimination. Results: AUCs of 0.826–0.870 were found for DLCST data based on PanCan risk prediction models. In the DLCST, age and family history were significant predictors (p = 0.001 and p = 0.013). Female sex was not confirmed to be associated with higher risk of lung cancer...

  12. Factorial and predictive validity of the expectations about counseling-brief (EAC-B) with clients seeking counseling.

    Science.gov (United States)

    Anderson, Timothy; Patterson, Candace L; McClintock, Andrew S; Song, Xiaoxia

    2013-10-01

    Our goals in this study were to define the factorial structure of treatment expectations for a sample of treatment-seeking clients and to understand the predictive validity of those expectations. A sample of 353 clients who were about to begin counseling at a university counseling center or at a psychology clinic completed the Expectations About Counseling-Brief form (EAC-B) and then completed measures of the working alliance, session quality, and symptom distress throughout the treatment. Principal components analysis resulted in a 3-factor solution of EAC-B treatment expectations, which accounted for 48.0% of the total variance. Consistent with previous research, the 3 factors were labeled client involvement, counselor expertise, and facilitative conditions. Among clients with prior treatment experience, a meaningful 4-factor solution was achieved; it involved the counselor expertise factor being split into 2 subgroups labeled "counselor directive helping" and "counselor subjective expertise." The predictive validity of these 3 factors found that each of the 3 EAC-B factor-derived scales, as well the total EAC-B score, was predictive of clients' (but not therapists') ratings of the therapeutic alliance as well as ratings of session depth, smoothness, and positivity. Client involvement, facilitative conditions, and EAC-B Total score (but not counselor expertise) predicted therapy outcome.

  13. Implicit and explicit preferences for physical attractiveness in a romantic partner: a double dissociation in predictive validity.

    Science.gov (United States)

    Eastwick, Paul W; Eagly, Alice H; Finkel, Eli J; Johnson, Sarah E

    2011-11-01

    Five studies develop and examine the predictive validity of an implicit measure of the preference for physical attractiveness in a romantic partner. Three hypotheses were generally supported. First, 2 variants of the go/no-go association task revealed that participants, on average, demonstrate an implicit preference (i.e., a positive spontaneous affective reaction) for physical attractiveness in a romantic partner. Second, these implicit measures were not redundant with a traditional explicit measure: The correlation between these constructs was .00 on average, and the implicit measures revealed no reliable sex differences, unlike the explicit measure. Third, explicit and implicit measures exhibited a double dissociation in predictive validity. Specifically, explicit preferences predicted the extent to which attractiveness was associated with participants' romantic interest in opposite-sex photographs but not their romantic interest in real-life opposite-sex speed-daters or confederates. Implicit preferences showed the opposite pattern. This research extends prior work on implicit processes in romantic relationships and offers the first demonstration that any measure of a preference for a particular characteristic in a romantic partner (an implicit measure of physical attractiveness, in this case) predicts individuals' evaluation of live potential romantic partners.

  14. GMAT versus Alternatives: Predictive Validity Evidence from Central Europe and the Middle East

    Science.gov (United States)

    Koys, Daniel

    2010-01-01

    The author found that the GPA at the end of the MBA program is most accurately predicted by the Graduate Management Admission Test (GMAT) and the Test of English as a Foreign Language (TOEFL). MBA GPA is also predicted, though less accurately, by the Scholastic Level Exam, a mathematics test, undergraduate GPA, and previous career progression. If…

  15. GMAT versus Alternatives: Predictive Validity Evidence from Central Europe and the Middle East

    Science.gov (United States)

    Koys, Daniel

    2010-01-01

    The author found that the GPA at the end of the MBA program is most accurately predicted by the Graduate Management Admission Test (GMAT) and the Test of English as a Foreign Language (TOEFL). MBA GPA is also predicted, though less accurately, by the Scholastic Level Exam, a mathematics test, undergraduate GPA, and previous career progression. If…

  16. An efficient numerical target strength prediction model: Validation against analysis solutions

    NARCIS (Netherlands)

    Fillinger, L.; Nijhof, M.J.J.; Jong, C.A.F. de

    2014-01-01

    A decade ago, TNO developed RASP (Rapid Acoustic Signature Prediction), a numerical model for the prediction of the target strength of immersed underwater objects. The model is based on Kirchhoff diffraction theory. It is currently being improved to model refraction, angle dependent reflection and t

  17. Prediction model of RSV-hospitalization in late preterm infants : An update and validation study

    NARCIS (Netherlands)

    Korsten, Koos; Blanken, Maarten O; Nibbelke, Elisabeth E; Moons, Karel G M; Bont, Louis

    2016-01-01

    BACKGROUND: New vaccines and RSV therapeutics have been developed in the past decade. With approval of these new pharmaceuticals on the horizon, new challenges lie ahead in selecting the appropriate target population. We aimed to improve a previously published prediction model for prediction of RSV-

  18. Prediction model of RSV-hospitalization in late preterm infants: An update and validation study

    NARCIS (Netherlands)

    Korsten, K.; Blanken, M.O.; Nibbelke, E.E.; Moons, K.G.; Bont, L.; Liem, K.D.

    2016-01-01

    BACKGROUND: New vaccines and RSV therapeutics have been developed in the past decade. With approval of these new pharmaceuticals on the horizon, new challenges lie ahead in selecting the appropriate target population. We aimed to improve a previously published prediction model for prediction of RSV-

  19. Driving and Low Vision: Validity of Assessments for Predicting Performance of Drivers

    Science.gov (United States)

    Strong, J. Graham; Jutai, Jeffrey W.; Russell-Minda, Elizabeth; Evans, Mal

    2008-01-01

    The authors conducted a systematic review to examine whether vision-related assessments can predict the driving performance of individuals who have low vision. The results indicate that measures of visual field, contrast sensitivity, cognitive and attention-based tests, and driver screening tools have variable utility for predicting real-world…

  20. Validation of Occupants’ Behaviour Models for Indoor Quality Parameter and Energy Consumption Prediction

    DEFF Research Database (Denmark)

    Fabi, Valentina; Sugliano, Martina; Andersen, Rune Korsholm

    2015-01-01

    . For this reason, the validation of occupant's behavioral models is an issue that is gaining importance.In this paper validation was carried out through dynamic Building Energy Performance simulation (BEPS); behavioral models of windows opening and thermostats set-point published in literature were implemented...... in a dynamic BEPS software and the obtained results in terms of temperature, relative humidity and CO2 concentration were compared to real measurements. Through this comparison it will be possible to verify the accuracy of the implemented behavioral models.The models were able to reproduce the general...

  1. Prediction and validation of burnout curves for Goettelborn char using reaction kinetics determined in shock tube experiments

    Energy Technology Data Exchange (ETDEWEB)

    Moors, J.H.J.; Banin, V.E.; Haas, J.H.P.; Weber, R.; Veefkind, A. [Eindhoven University of Technology, Eindhoven (Netherlands). Dept. of Applied Physics

    1999-01-01

    Using a shock tube facility the combustion characteristics of pulverised char ({lt} 10 {mu}m) were measured. A prediction was made for the burnout behaviour of a commercial sized char particle (75-90 {mu}m) in different ambient conditions using a `pseudo kinetic` approach. In this approach the kinetic rate of a surface containing micro pores is determined and these `pseudo kinetics` are then applied to the larger particle not taking into account the micro pores. Comparison of the predictions with measurements done with an isothermal plug flow reactor showed this approach to be valid within experimental error for low burnout. A linear decrease of the kinetic reaction rate with burnout is shown to predict the burnout behaviour in the complete range of burnout. A possible explanation for this linear decrease could be a growing fraction of non-combustible material in the char particles during burnout. 11 refs., 6 figs., 2 tabs.

  2. Behavioral Indicators on a Mobile Sensing Platform Predict Clinically Validated Psychiatric Symptoms of Mood and Anxiety Disorders

    Science.gov (United States)

    Place, Skyler; Rubin, Channah; Gorrostieta, Cristina; Mead, Caroline; Kane, John; Marx, Brian P; Feast, Joshua; Deckersbach, Thilo; Pentland, Alex “Sandy”; Nierenberg, Andrew; Azarbayejani, Ali

    2017-01-01

    Background There is a critical need for real-time tracking of behavioral indicators of mental disorders. Mobile sensing platforms that objectively and noninvasively collect, store, and analyze behavioral indicators have not yet been clinically validated or scalable. Objective The aim of our study was to report on models of clinical symptoms for post-traumatic stress disorder (PTSD) and depression derived from a scalable mobile sensing platform. Methods A total of 73 participants (67% [49/73] male, 48% [35/73] non-Hispanic white, 33% [24/73] veteran status) who reported at least one symptom of PTSD or depression completed a 12-week field trial. Behavioral indicators were collected through the noninvasive mobile sensing platform on participants’ mobile phones. Clinical symptoms were measured through validated clinical interviews with a licensed clinical social worker. A combination hypothesis and data-driven approach was used to derive key features for modeling symptoms, including the sum of outgoing calls, count of unique numbers texted, absolute distance traveled, dynamic variation of the voice, speaking rate, and voice quality. Participants also reported ease of use and data sharing concerns. Results Behavioral indicators predicted clinically assessed symptoms of depression and PTSD (cross-validated area under the curve [AUC] for depressed mood=.74, fatigue=.56, interest in activities=.75, and social connectedness=.83). Participants reported comfort sharing individual data with physicians (Mean 3.08, SD 1.22), mental health providers (Mean 3.25, SD 1.39), and medical researchers (Mean 3.03, SD 1.36). Conclusions Behavioral indicators passively collected through a mobile sensing platform predicted symptoms of depression and PTSD. The use of mobile sensing platforms can provide clinically validated behavioral indicators in real time; however, further validation of these models and this platform in large clinical samples is needed. PMID:28302595

  3. Development and validation of a prediction model for long-term sickness absence based on occupational health survey variables.

    Science.gov (United States)

    Roelen, Corné; Thorsen, Sannie; Heymans, Martijn; Twisk, Jos; Bültmann, Ute; Bjørner, Jakob

    2016-11-10

    The purpose of this study is to develop and validate a prediction model for identifying employees at increased risk of long-term sickness absence (LTSA), by using variables commonly measured in occupational health surveys. Based on the literature, 15 predictor variables were retrieved from the DAnish National working Environment Survey (DANES) and included in a model predicting incident LTSA (≥4 consecutive weeks) during 1-year follow-up in a sample of 4000 DANES participants. The 15-predictor model was reduced by backward stepwise statistical techniques and then validated in a sample of 2524 DANES participants, not included in the development sample. Identification of employees at increased LTSA risk was investigated by receiver operating characteristic (ROC) analysis; the area-under-the-ROC-curve (AUC) reflected discrimination between employees with and without LTSA during follow-up. The 15-predictor model was reduced to a 9-predictor model including age, gender, education, self-rated health, mental health, prior LTSA, work ability, emotional job demands, and recognition by the management. Discrimination by the 9-predictor model was significant (AUC = 0.68; 95% CI 0.61-0.76), but not practically useful. A prediction model based on occupational health survey variables identified employees with an increased LTSA risk, but should be further developed into a practically useful tool to predict the risk of LTSA in the general working population. Implications for rehabilitation Long-term sickness absence risk predictions would enable healthcare providers to refer high-risk employees to rehabilitation programs aimed at preventing or reducing work disability. A prediction model based on health survey variables discriminates between employees at high and low risk of long-term sickness absence, but discrimination was not practically useful. Health survey variables provide insufficient information to determine long-term sickness absence risk profiles. There is a need for

  4. Design and validation of a prehospital stroke scale to predict large arterial occlusion: the rapid arterial occlusion evaluation scale.

    Science.gov (United States)

    Pérez de la Ossa, Natalia; Carrera, David; Gorchs, Montse; Querol, Marisol; Millán, Mònica; Gomis, Meritxell; Dorado, Laura; López-Cancio, Elena; Hernández-Pérez, María; Chicharro, Vicente; Escalada, Xavier; Jiménez, Xavier; Dávalos, Antoni

    2014-01-01

    We aimed to develop and validate a simple prehospital stroke scale to predict the presence of large vessel occlusion (LVO) in patients with acute stroke. The Rapid Arterial oCclusion Evaluation (RACE) scale was designed based on the National Institutes of Health Stroke Scale (NIHSS) items with a higher predictive value of LVO on a retrospective cohort of 654 patients with acute ischemic stroke: facial palsy (scored 0-2), arm motor function (0-2), leg motor function (0-2), gaze (0-1), and aphasia or agnosia (0-2). Thereafter, the RACE scale was validated prospectively in the field by trained medical emergency technicians in 357 consecutive patients transferred by Emergency Medical Services to our Comprehensive Stroke Center. Neurologists evaluated stroke severity at admission and LVO was diagnosed by transcranial duplex, computed tomography, or MR angiography. Receiver operating curve, sensitivity, specificity, and global accuracy of the RACE scale were analyzed to evaluate its predictive value for LVO. In the prospective cohort, the RACE scale showed a strong correlation with NIHSS (r=0.76; P<0.001). LVO was detected in 76 of 357 patients (21%). Receiver operating curves showed a similar capacity to predict LVO of the RACE scale compared with the NIHSS (area under the curve 0.82 and 0.85, respectively). A RACE scale≥5 had sensitivity 0.85, specificity 0.68, positive predictive value 0.42, and negative predictive value 0.94 for detecting LVO. The RACE scale is a simple tool that can accurately assess stroke severity and identify patients with acute stroke with large artery occlusion at prehospital setting by medical emergency technicians.

  5. Validation of predictive equations for resting energy expenditure in Japanese pediatric Crohn's disease patients: preliminary study.

    Science.gov (United States)

    Arai, Katsuhiro; Funayama, Rie; Takahashi, Mieko; Sakai, Rie; Shimizu, Hirotaka; Obayashi, Naho; Matsui, Akira

    2015-04-01

    Predictive equations are often used to estimate resting energy expenditure (REE). Determining the appropriate equation for different patient types, however, remains inconclusive, as in the case of Japanese children with Crohn's disease (CD). The aim of this study was to identify an appropriate predictive equation for measuring REE in Japanese children with CD. Twelve Japanese children with CD managed at the National Center for Child Health and Development in Tokyo, Japan, were studied. REE (kcal/day) was measured using indirect calorimetry. The predictive equations used were the Japanese Dietary Reference Intakes (2010), the Schofield equation, the Food and Agriculture Organization/World Health Organization/United Nations University (FAO/WHO/UNU) equation and the Cunningham equation. Difference between predicted and measured REE was analyzed on Bland-Altman plot. Japanese Dietary Reference Intakes (2010) had the smallest difference between predicted and measured REE. Weight was the primary predictor of REE on multiple regression analysis. As well, Japanese Dietary Reference Intakes (2010) had the highest ratio of weight to predicted REE (98.5%). Of the four equations, Japanese Dietary Reference Intakes (2010) appeared to be the most practical and accurate predictive equation for REE in Japanese children with CD. © 2014 Japan Pediatric Society.

  6. Improvement of walking speed prediction by accelerometry and altimetry, validated by satellite positioning.

    Science.gov (United States)

    Perrin, O; Terrier, P; Ladetto, Q; Merminod, B; Schutz, Y

    2000-03-01

    Activity monitors based on accelerometry are used to predict the speed and energy cost of walking at 0% slope, but not at other inclinations. Parallel measurements of body accelerations and altitude variation were studied to determine whether walking speed prediction could be improved. Fourteen subjects walked twice along a 1.3 km circuit with substantial slope variations (-17% to +17%). The parameters recorded were body acceleration using a uni-axial accelerometer, altitude variation using differential barometry, and walking speed using satellite positioning (DGPS). Linear regressions were calculated between acceleration and walking speed, and between acceleration/altitude and walking speed. These predictive models, calculated using the data from the first circuit run, were used to predict speed during the second circuit. Finally the predicted velocity was compared with the measured one. The result was that acceleration alone failed to predict speed (mean r = 0.4). Adding altitude variation improved the prediction (mean r = 0.7). With regard to the altitude/acceleration-speed relationship, substantial inter-individual variation was found. It is concluded that accelerometry, combined with altitude measurement, can assess position variations of humans provided inter-individual variation is taken into account. It is also confirmed that DGPS can be used for outdoor walking speed measurements, opening up new perspectives in the field of biomechanics.

  7. Dimensionality and predictive validity of the HAM-Nat, a test of natural sciences for medical school admission

    Directory of Open Access Journals (Sweden)

    Hissbach Johanna C

    2011-10-01

    Full Text Available Abstract Background Knowledge in natural sciences generally predicts study performance in the first two years of the medical curriculum. In order to reduce delay and dropout in the preclinical years, Hamburg Medical School decided to develop a natural science test (HAM-Nat for student selection. In the present study, two different approaches to scale construction are presented: a unidimensional scale and a scale composed of three subject specific dimensions. Their psychometric properties and relations to academic success are compared. Methods 334 first year medical students of the 2006 cohort responded to 52 multiple choice items from biology, physics, and chemistry. For the construction of scales we generated two random subsamples, one for development and one for validation. In the development sample, unidimensional item sets were extracted from the item pool by means of weighted least squares (WLS factor analysis, and subsequently fitted to the Rasch model. In the validation sample, the scales were subjected to confirmatory factor analysis and, again, Rasch modelling. The outcome measure was academic success after two years. Results Although the correlational structure within the item set is weak, a unidimensional scale could be fitted to the Rasch model. However, psychometric properties of this scale deteriorated in the validation sample. A model with three highly correlated subject specific factors performed better. All summary scales predicted academic success with an odds ratio of about 2.0. Prediction was independent of high school grades and there was a slight tendency for prediction to be better in females than in males. Conclusions A model separating biology, physics, and chemistry into different Rasch scales seems to be more suitable for item bank development than a unidimensional model, even when these scales are highly correlated and enter into a global score. When such a combination scale is used to select the upper quartile of

  8. Predictive Validity of a Multiple-Choice Test for Placement in a Community College

    Science.gov (United States)

    Verbout, Mary F.

    2013-01-01

    Multiple-choice tests of punctuation and usage are used throughout the United States to assess the writing skills of new community college students in order to place them in either a basic writing course or first-year composition. To determine whether using the COMPASS Writing Test (CWT) is a valid placement at a community college, student test…

  9. Cross-Validation of a PACER Prediction Equation for Assessing Aerobic Capacity in Hungarian Youth

    Science.gov (United States)

    Saint-Maurice, Pedro F.; Welk, Gregory J.; Finn, Kevin J.; Kaj, Mónika

    2015-01-01

    Purpose: The purpose of this article was to evaluate the validity of the Progressive Aerobic Cardiovascular and Endurance Run (PACER) test in a sample of Hungarian youth. Method: Approximately 500 participants (aged 10-18 years old) were randomly selected across Hungary to complete both laboratory (maximal treadmill protocol) and field assessments…

  10. Identifying and Validating Selection Tools for Predicting Officer Performance and Retention

    Science.gov (United States)

    2017-05-01

    developed for use in the validation analyses. Criterion Measures Criterion measurement methods were organized into four categories...Teresa L. Russell, Editor Cheryl J. Paullin, Editor Human Resources Research Organization Peter J. Legree, Editor Robert N. Kilcullen, Editor...for the Department of the Army by Human Resources Research Organization Technical review by Rebekkah Beeco, U.S. Army Research Institute

  11. Development and internal validation of a multivariable model to predict perinatal death in pregnancy hypertension

    NARCIS (Netherlands)

    Payne, Beth A.; Groen, Henk; Ukah, U. Vivian; Ansermino, J. Mark; Bhutta, Zulfiqar; Grobman, William; Hall, David R.; Hutcheon, Jennifer A.; Magee, Laura A.; von Dadelszen, Peter

    2015-01-01

    Objective: To develop and internally validate a prognostic model for perinatal death that could guide community-based antenatal care of women with a hypertensive disorder of pregnancy (HDP) in low-resourced settings as part of a mobile health application. Study design: Using data from 1688 women (11

  12. Concurrent and Predictive Validity of the Battelle Development Inventory at the First Grade Level.

    Science.gov (United States)

    Guidubaldi, John; Perry, Joseph D.

    1984-01-01

    A random sample (n=50) of a school district's total grade level was evaluated in kindergarten, then in first grade using a comprehensive battery of assessments. Data were interpreted to support the Battelle Developmental Inventory as a valid multifactored assessment for use with both handicapped and nonhandicapped young children. (Author/BS)

  13. Assessing the capability of numerical methods to predict earthquake ground motion: the Euroseistest verification and validation project

    Science.gov (United States)

    Chaljub, E. O.; Bard, P.; Tsuno, S.; Kristek, J.; Moczo, P.; Franek, P.; Hollender, F.; Manakou, M.; Raptakis, D.; Pitilakis, K.

    2009-12-01

    During the last decades, an important effort has been dedicated to develop accurate and computationally efficient numerical methods to predict earthquake ground motion in heterogeneous 3D media. The progress in methods and increasing capability of computers have made it technically feasible to calculate realistic seismograms for frequencies of interest in seismic design applications. In order to foster the use of numerical simulation in practical prediction, it is important to (1) evaluate the accuracy of current numerical methods when applied to realistic 3D applications where no reference solution exists (verification) and (2) quantify the agreement between recorded and numerically simulated earthquake ground motion (validation). Here we report the results of the Euroseistest verification and validation project - an ongoing international collaborative work organized jointly by the Aristotle University of Thessaloniki, Greece, the Cashima research project (supported by the French nuclear agency, CEA, and the Laue-Langevin institute, ILL, Grenoble), and the Joseph Fourier University, Grenoble, France. The project involves more than 10 international teams from Europe, Japan and USA. The teams employ the Finite Difference Method (FDM), the Finite Element Method (FEM), the Global Pseudospectral Method (GPSM), the Spectral Element Method (SEM) and the Discrete Element Method (DEM). The project makes use of a new detailed 3D model of the Mygdonian basin (about 5 km wide, 15 km long, sediments reach about 400 m depth, surface S-wave velocity is 200 m/s). The prime target is to simulate 8 local earthquakes with magnitude from 3 to 5. In the verification, numerical predictions for frequencies up to 4 Hz for a series of models with increasing structural and rheological complexity are analyzed and compared using quantitative time-frequency goodness-of-fit criteria. Predictions obtained by one FDM team and the SEM team are close and different from other predictions

  14. Validated Design and Analysis Tool for Small Vertical-Lift Unmanned Air Vehicle Noise Prediction Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A procedure and supporting computer code for the prediction of noise that radiates from small, vertical lift UAV aircraft is proposed. The resulting building block...

  15. Predictive Validity of the Columbia-Suicide Severity Rating Scale for Short-Term Suicidal Behavior

    DEFF Research Database (Denmark)

    Conway, Paul Maurice; Erlangsen, Annette; Teasdale, Thomas William;

    2016-01-01

    behavior predicted subsequent suicidal behavior (actual attempts and suicidal behavior of any type, including preparatory acts, aborted, interrupted and actual attempts; mean follow-up of 80.8 days, SD = 52.4). Furthermore, we examined whether suicidal ideation severity and intensity incrementally...... predicted suicidal behavior at follow-up over and above suicidal behavior at baseline. Results: Actual suicide attempts at baseline strongly predicted suicide attempts at follow-up. Baseline suicidal ideation severity and intensity did not significantly predict future actual attempts over and above baseline...... attempts. The suicidal ideation intensity items deterrents and duration were significant predictors of subsequent actual attempts after adjustment for baseline suicide attempts and suicidal behavior of any type, respectively. Suicidal ideation severity and intensity, and the intensity items frequency...

  16. Feature selection and validated predictive performance in the domain of Legionella pneumophila: A comparative study

    NARCIS (Netherlands)

    T. van der Ploeg (Tjeerd); E.W. Steyerberg (Ewout)

    2016-01-01

    textabstractBackground: Genetic comparisons of clinical and environmental Legionella strains form an essential part of outbreak investigations. DNA microarrays often comprise many DNA markers (features). Feature selection and the development of prediction models are particularly challenging in this

  17. Predicting total fat mass from skinfold thicknesses in Japanese prepubertal children: a cross-sectional and longitudinal validation.

    Science.gov (United States)

    Midorikawa, Taishi; Ohta, Megumi; Hikihara, Yuki; Torii, Suguru; Bemben, Michael G; Sakamoto, Shizuo

    2011-01-01

    The present study was performed to develop regression based prediction equations for fat mass from skinfold thickness in Japanese children, and to investigate the cross-sectional and longitudinal validity of these equations. A total of 127 healthy Japanese prepubertal children aged 6-12 years were randomly separated into two groups: the model development group (54 boys and 44 girls) and the cross-sectional validation group (18 boys and 11 girls). Fat mass was initially determined by using DXA (Hologic Delphi A-QDR whole-body scanner) to provide reference data. Then, fat thickness was measured at triceps and subscapular using an Eiken-type skinfold calipers. Multiple anthropometric and DXA measures were obtained one year later for 28 of the original 127 subjects (longitudinal validation group: 14 boys and 14 girls). Strong significant correlations were observed between total fat mass by DXA measurement and the skinfold thickness × height measures by caliper in the model development group of boys and girls (R2=0.91-0.92, pSkinfold-derived prediction equations underestimate for obese children but are generally useful for estimating total fat mass in field research.

  18. Predictive validity and reliability of the Braden scale for risk assessment of pressure ulcers in an intensive care unit.

    Science.gov (United States)

    Lima-Serrano, M; González-Méndez, M I; Martín-Castaño, C; Alonso-Araujo, I; Lima-Rodríguez, J S

    2017-02-15

    Contribution to validation of the Braden scale in patients admitted to the ICU, based on an analysis of its reliability and predictive validity. An analytical, observational, longitudinal prospective study was carried out. Intensive Care Unit, Hospital Virgen del Rocío, Seville (Spain). Patients aged 18years or older and admitted for over 24hours to the ICU were included. Patients with pressure ulcers upon admission were excluded. A total of 335 patients were enrolled in two study periods of one month each. None. The presence of gradei-iv pressure ulcers was regarded as the main or dependent variable. Three categories were considered (demographic, clinical and prognostic) for the remaining variables. The incidence of patients who developed pressure ulcers was 8.1%. The proportion of gradei andii pressure ulcer was 40.6% and 59.4% respectively, highlighting the sacrum as the most frequently affected location. Cronbach's alpha coefficient in the assessments considered indicated good to moderate reliability. In the three evaluations made, a cutoff point of 12 was presented as optimal in the assessment of the first and second days of admission. In relation to the assessment of the day with minimum score, the optimal cutoff point was 10. The Braden scale shows insufficient predictive validity and poor precision for cutoff points of both 18 and 16, which are those accepted in the different clinical scenarios. Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  19. Hospitalization for community-acquired febrile urinary tract infection: validation and impact assessment of a clinical prediction rule.

    Science.gov (United States)

    Stalenhoef, Janneke E; van der Starre, Willize E; Vollaard, Albert M; Steyerberg, Ewout W; Delfos, Nathalie M; Leyten, Eliane M S; Koster, Ted; Ablij, Hans C; Van't Wout, Jan W; van Dissel, Jaap T; van Nieuwkoop, Cees

    2017-06-06

    There is a lack of severity assessment tools to identify adults presenting with febrile urinary tract infection (FUTI) at risk for complicated outcome and guide admission policy. We aimed to validate the Prediction Rule for Admission policy in Complicated urinary Tract InfeCtion LEiden (PRACTICE), a modified form of the pneumonia severity index, and to subsequentially assess its use in clinical practice. A prospective observational multicenter study for model validation (2004-2009), followed by a multicenter controlled clinical trial with stepped wedge cluster-randomization for impact assessment (2010-2014), with a follow up of 3 months. Paricipants were 1157 consecutive patients with a presumptive diagnosis of acute febrile UTI (787 in validation cohort and 370 in the randomized trial), enrolled at emergency departments of 7 hospitals and 35 primary care centers in the Netherlands. The clinical prediction rule contained 12 predictors of complicated course. In the randomized trial the PRACTICE included guidance on hospitalization for high risk (>100 points) and home discharge for low risk patients (urinary tract infection, futher improvement is necessary to reduce the occurrence of secondary hospital admissions. NTR4480 http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=4480 , registered retrospectively 25 mrt 2014 (during enrollment of subjects).

  20. Validation of a predictive model for the growth of Botrytis cinerea and Penicillium expansum on grape berries.

    Science.gov (United States)

    Judet-Correia, Daniela; Bollaert, Sophie; Duquenne, Alison; Charpentier, Claudine; Bensoussan, Maurice; Dantigny, Philippe

    2010-08-15

    The objective of this study was to develop and to validate a model for predicting the combined effect of temperature and a(w) on the radial growth rate, mu, of Botrytis cinerea and Penicillium expansum on grape berries. The proposed strategy was based on the gamma-concept developed previously [Zwietering, M.H., Wijtzes, T., de Wit, J.C., van't Riet, K. 1992. A decision support system for prediction of the microbial spoilage in foods. Journal of Food Protection. 12, 973-979]: mu=mu(opt).gamma(T).gamma(a(w)), where the gamma functions were cardinal models with inflection (CMI), mu(opt) the radial growth rate on grape berries. Firstly, the cardinal temperatures and a(w)'s were estimated independently from experiments carried out on Potato Dextrose Agar. Secondly, the gamma concept was validated i/ on a synthetic grape juice medium (SGJ) and ii/ on a grape juice agar (GJA). Accuracy and bias factors were closer to 1 with the latter analogue, thus suggesting that GJA should be preferred to SGJ. Thirdly, an experimental protocol taken into account the isotropic nature of fungal growth was developed for estimating mu(opt) on grape berries. This study demonstrated that CMI's can be validated on agri-food products over a wide range of temperature and a(w) using the described methodology.

  1. Prediction and experimental validation of novel STAT3 target genes in human cancer cells.

    Directory of Open Access Journals (Sweden)

    Young Min Oh

    Full Text Available The comprehensive identification of functional transcription factor binding sites (TFBSs is an important step in understanding complex transcriptional regulatory networks. This study presents a motif-based comparative approach, STAT-Finder, for identifying functional DNA binding sites of STAT3 transcription factor. STAT-Finder combines STAT-Scanner, which was designed to predict functional STAT TFBSs with improved sensitivity, and a motif-based alignment to minimize false positive prediction rates. Using two reference sets containing promoter sequences of known STAT3 target genes, STAT-Finder identified functional STAT3 TFBSs with enhanced prediction efficiency and sensitivity relative to other conventional TFBS prediction tools. In addition, STAT-Finder identified novel STAT3 target genes among a group of genes that are over-expressed in human cancer cells. The binding of STAT3 to the predicted TFBSs was also experimentally confirmed through chromatin immunoprecipitation. Our proposed method provides a systematic approach to the prediction of functional TFBSs that can be applied to other TFs.

  2. Predicting Glycerophosphoinositol Identities in Lipidomic Datasets Using VaLID (Visualization and Phospholipid Identification—An Online Bioinformatic Search Engine

    Directory of Open Access Journals (Sweden)

    Graeme S. V. McDowell

    2014-01-01

    Full Text Available The capacity to predict and visualize all theoretically possible glycerophospholipid molecular identities present in lipidomic datasets is currently limited. To address this issue, we expanded the search-engine and compositional databases of the online Visualization and Phospholipid Identification (VaLID bioinformatic tool to include the glycerophosphoinositol superfamily. VaLID v1.0.0 originally allowed exact and average mass libraries of 736,584 individual species from eight phospholipid classes: glycerophosphates, glyceropyrophosphates, glycerophosphocholines, glycerophosphoethanolamines, glycerophosphoglycerols, glycerophosphoglycerophosphates, glycerophosphoserines, and cytidine 5′-diphosphate 1,2-diacyl-sn-glycerols to be searched for any mass to charge value (with adjustable tolerance levels under a variety of mass spectrometry conditions. Here, we describe an update that now includes all possible glycerophosphoinositols, glycerophosphoinositol monophosphates, glycerophosphoinositol bisphosphates, and glycerophosphoinositol trisphosphates. This update expands the total number of lipid species represented in the VaLID v2.0.0 database to 1,473,168 phospholipids. Each phospholipid can be generated in skeletal representation. A subset of species curated by the Canadian Institutes of Health Research Training Program in Neurodegenerative Lipidomics (CTPNL team is provided as an array of high-resolution structures. VaLID is freely available and responds to all users through the CTPNL resources web site.

  3. Predicting glycerophosphoinositol identities in lipidomic datasets using VaLID (Visualization and Phospholipid Identification)--an online bioinformatic search engine.

    Science.gov (United States)

    McDowell, Graeme S V; Blanchard, Alexandre P; Taylor, Graeme P; Figeys, Daniel; Fai, Stephen; Bennett, Steffany A L

    2014-01-01

    The capacity to predict and visualize all theoretically possible glycerophospholipid molecular identities present in lipidomic datasets is currently limited. To address this issue, we expanded the search-engine and compositional databases of the online Visualization and Phospholipid Identification (VaLID) bioinformatic tool to include the glycerophosphoinositol superfamily. VaLID v1.0.0 originally allowed exact and average mass libraries of 736,584 individual species from eight phospholipid classes: glycerophosphates, glyceropyrophosphates, glycerophosphocholines, glycerophosphoethanolamines, glycerophosphoglycerols, glycerophosphoglycerophosphates, glycerophosphoserines, and cytidine 5'-diphosphate 1,2-diacyl-sn-glycerols to be searched for any mass to charge value (with adjustable tolerance levels) under a variety of mass spectrometry conditions. Here, we describe an update that now includes all possible glycerophosphoinositols, glycerophosphoinositol monophosphates, glycerophosphoinositol bisphosphates, and glycerophosphoinositol trisphosphates. This update expands the total number of lipid species represented in the VaLID v2.0.0 database to 1,473,168 phospholipids. Each phospholipid can be generated in skeletal representation. A subset of species curated by the Canadian Institutes of Health Research Training Program in Neurodegenerative Lipidomics (CTPNL) team is provided as an array of high-resolution structures. VaLID is freely available and responds to all users through the CTPNL resources web site.

  4. The spatiotemporal program of DNA replication is associated with specific combinations of chromatin marks in human cells.

    Directory of Open Access Journals (Sweden)

    Franck Picard

    2014-05-01

    Full Text Available The duplication of mammalian genomes is under the control of a spatiotemporal program that orchestrates the positioning and the timing of firing of replication origins. The molecular mechanisms coordinating the activation of about [Formula: see text] predicted origins remain poorly understood, partly due to the intrinsic rarity of replication bubbles, making it difficult to purify short nascent strands (SNS. The precise identification of origins based on the high-throughput sequencing of SNS constitutes a new methodological challenge. We propose a new statistical method with a controlled resolution, adapted to the detection of replication origins from SNS data. We detected an average of 80,000 replication origins in different cell lines. To evaluate the consistency between different protocols, we compared SNS detections with bubble trapping detections. This comparison demonstrated a good agreement between genome-wide methods, with 65% of SNS-detected origins validated by bubble trapping, and 44% of bubble trapping origins validated by SNS origins, when compared at the same resolution. We investigated the interplay between the spatial and the temporal programs of replication at fine scales. We show that most of the origins detected in regions replicated in early S phase are shared by all the cell lines investigated whereas cell-type-specific origins tend to be replicated in late S phase. We shed a new light on the key role of CpG islands, by showing that 80% of the origins associated with CGIs are constitutive. Our results further show that at least 76% of CGIs are origins of replication. The analysis of associations with chromatin marks at different timing of cell division revealed new potential epigenetic regulators driving the spatiotemporal activity of replication origins. We highlight the potential role of H4K20me1 and H3K27me3, the coupling of which is correlated with increased efficiency of replication origins, clearly identifying those

  5. Genome-wide prediction and validation of sigma70 promoters in Lactobacillus plantarum WCFS1.

    Directory of Open Access Journals (Sweden)

    Tilman J Todt

    Full Text Available BACKGROUND: In prokaryotes, sigma factors are essential for directing the transcription machinery towards promoters. Various sigma factors have been described that recognize, and bind to specific DNA sequence motifs in promoter sequences. The canonical sigma factor σ(70 is commonly involved in transcription of the cell's housekeeping genes, which is mediated by the conserved σ(70 promoter sequence motifs. In this study the σ(70-promoter sequences in Lactobacillus plantarum WCFS1 were predicted using a genome-wide analysis. The accuracy of the transcriptionally-active part of this promoter prediction was subsequently evaluated by correlating locations of predicted promoters with transcription start sites inferred from the 5'-ends of transcripts detected by high-resolution tiling array transcriptome datasets. RESULTS: To identify σ(70-related promoter sequences, we performed a genome-wide sequence motif scan of the L. plantarum WCFS1 genome focussing on the regions upstream of protein-encoding genes. We obtained several highly conserved motifs including those resembling the conserved σ(70-promoter consensus. Position weight matrices-based models of the recovered σ(70-promoter sequence motif were employed to identify 3874 motifs with significant similarity (p-value<10(-4 to the model-motif in the L. plantarum genome. Genome-wide transcript information deduced from whole genome tiling-array transcriptome datasets, was used to infer transcription start sites (TSSs from the 5'-end of transcripts. By this procedure, 1167 putative TSSs were identified that were used to corroborate the transcriptionally active fraction of these predicted promoters. In total, 568 predicted promoters were found in proximity (≤ 40 nucleotides of the putative TSSs, showing a highly significant co-occurrence of predicted promoter and TSS (p-value<10(-263. CONCLUSIONS: High-resolution tiling arrays provide a suitable source to infer TSSs at a genome-wide level, and

  6. The Development and Validation of an Actuarial Risk Assessment Tool for the Prediction of First-Time Offending.

    Science.gov (United States)

    Assink, Mark; van der Put, Claudia E; Stams, Geert Jan J M

    2016-05-01

    For prevention purposes, it is important that police officers can estimate the risk for delinquency among juveniles who were involved in a criminal offense, but not in the role of a suspect. In the present study, the Youth Actuarial Risk Assessment Tool for First-Time Offending (Y-ARAT-FO) was developed based solely on police records with the aim to enable Dutch police officers to predict the risk for first-time offending. For the construction of this initial screening instrument, an Exhaustive Chi-squared Automatic Interaction Detector (Exhaustive CHAID) analysis was performed on a data set that was retrieved from the Dutch police system. The Y-ARAT-FO was developed on a sample of 1,368 juveniles and validated on a different sample of 886 juveniles showing moderate predictive accuracy in the validation sample (area under the receiver operating characteristic curve [AUC] = .728). The predictive accuracy of the Y-ARAT-FO was considered sufficient to justify its use as an initial screening instrument by the Dutch police.

  7. Predictive validity of the classroom strategies scale-observer form on statewide testing scores: an initial investigation.

    Science.gov (United States)

    Reddy, Linda A; Fabiano, Gregory A; Dudek, Christopher M; Hsu, Louis

    2013-12-01

    The present study examined the validity of a teacher observation measure, the Classroom Strategies Scale--Observer Form (CSS), as a predictor of student performance on statewide tests of mathematics and English language arts. The CSS is a teacher practice observational measure that assesses evidence-based instructional and behavioral management practices in elementary school. A series of two-level hierarchical generalized linear models were fitted to data of a sample of 662 third- through fifth-grade students to assess whether CSS Part 2 Instructional Strategy and Behavioral Management Strategy scale discrepancy scores (i.e., ∑ |recommended frequency--frequency ratings|) predicted statewide mathematics and English language arts proficiency scores when percentage of minority students in schools was controlled. Results indicated that the Instructional Strategy scale discrepancy scores significantly predicted mathematics and English language arts proficiency scores: Relatively larger discrepancies on observer ratings of what teachers did versus what should have been done were associated with lower proficiency scores. Results offer initial evidence of the predictive validity of the CSS Part 2 Instructional Strategy discrepancy scores on student academic outcomes.

  8. Multivariate meta-analysis of individual participant data helped externally validate the performance and implementation of a prediction model.

    Science.gov (United States)

    Snell, Kym I E; Hua, Harry; Debray, Thomas P A; Ensor, Joie; Look, Maxime P; Moons, Karel G M; Riley, Richard D

    2016-01-01

    Our aim was to improve meta-analysis methods for summarizing a prediction model's performance when individual participant data are available from multiple studies for external validation. We suggest multivariate meta-analysis for jointly synthesizing calibration and discrimination performance, while accounting for their correlation. The approach estimates a prediction model's average performance, the heterogeneity in performance across populations, and the probability of "good" performance in new populations. This allows different implementation strategies (e.g., recalibration) to be compared. Application is made to a diagnostic model for deep vein thrombosis (DVT) and a prognostic model for breast cancer mortality. In both examples, multivariate meta-analysis reveals that calibration performance is excellent on average but highly heterogeneous across populations unless the model's intercept (baseline hazard) is recalibrated. For the cancer model, the probability of "good" performance (defined by C statistic ≥0.7 and calibration slope between 0.9 and 1.1) in a new population was 0.67 with recalibration but 0.22 without recalibration. For the DVT model, even with recalibration, there was only a 0.03 probability of "good" performance. Multivariate meta-analysis can be used to externally validate a prediction model's calibration and discrimination performance across multiple populations and to evaluate different implementation strategies. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  9. In Silico Prediction and Validation of Gfap as an miR-3099 Target in Mouse Brain.

    Science.gov (United States)

    Abidin, Shahidee Zainal; Leong, Jia-Wen; Mahmoudi, Marzieh; Nordin, Norshariza; Abdullah, Syahril; Cheah, Pike-See; Ling, King-Hwa

    2017-08-01

    MicroRNAs are small non-coding RNAs that play crucial roles in the regulation of gene expression and protein synthesis during brain development. MiR-3099 is highly expressed throughout embryogenesis, especially in the developing central nervous system. Moreover, miR-3099 is also expressed at a higher level in differentiating neurons in vitro, suggesting that it is a potential regulator during neuronal cell development. This study aimed to predict the target genes of miR-3099 via in-silico analysis using four independent prediction algorithms (miRDB, miRanda, TargetScan, and DIANA-micro-T-CDS) with emphasis on target genes related to brain development and function. Based on the analysis, a total of 3,174 miR-3099 target genes were predicted. Those predicted by at least three algorithms (324 genes) were subjected to DAVID bioinformatics analysis to understand their overall functional themes and representation. The analysis revealed that nearly 70% of the target genes were expressed in the nervous system and a significant proportion were associated with transcriptional regulation and protein ubiquitination mechanisms. Comparison of in situ hybridization (ISH) expression patterns of miR-3099 in both published and in-house-generated ISH sections with the ISH sections of target genes from the Allen Brain Atlas identified 7 target genes (Dnmt3a, Gabpa, Gfap, Itga4, Lxn, Smad7, and Tbx18) having expression patterns complementary to miR-3099 in the developing and adult mouse brain samples. Of these, we validated Gfap as a direct downstream target of miR-3099 using the luciferase reporter gene system. In conclusion, we report the successful prediction and validation of Gfap as an miR-3099 target gene using a combination of bioinformatics resources with enrichment of annotations based on functional ontologies and a spatio-temporal expression dataset.

  10. Predicting Estimates of Premorbid Memory Functioning: Validation in a Dementia Sample

    Science.gov (United States)

    Duff, Kevin; Chelune, Gordon J.; Dennett, Kathryn

    2011-01-01

    Formulae to estimate premorbid memory functioning in a sample of cognitively intact older adults have been developed. These formulae were validated in a small sample of patients with amnestic Mild Cognitive Impairment. However, further validation is clearly needed. The current study applied these formulae to a sample of 1,059 patients referred to a dementia clinic and compared the premorbid estimates of memory functioning with current memory abilities. Large and statistically significant differences were observed in the current sample, with premorbid memory scores exceeding current memory scores. Although some cautions should be observed when using these estimates clinically, growing support for these estimates of premorbid memory abilities may aid clinicians in determining change across time in older patients. PMID:22024960

  11. Simulation validation and flight prediction of UH-60A Black Hawk helicopter/slung load characteristics

    OpenAIRE

    Tyson, Peter H.

    1999-01-01

    Helicopter/slung load systems are two body systems in which the slung load adds its rigid body dynamics, aerodynamics, and sling stretching dynamics to the helicopter. The slung load can degrade helicopter handling qualities and reduce the flight envelope of the helicopter. Confirmation of system stability parameters and envelope is desired, but flight test evaluation is time consuming and costly. A simulation model validated for handling quality assessments would significantly reduce resourc...

  12. Development and validation of skinfold-thickness prediction equations with a 4-compartment model.

    Science.gov (United States)

    Peterson, Matthew J; Czerwinski, Stefan A; Siervogel, Roger M

    2003-05-01

    Skinfold-thickness measurements are commonly obtained for the indirect assessment of body composition. We developed new skinfold-thickness equations by using a 4-compartment model as the reference. Additionally, we compared our new equations with the Durnin and Womersley and Jackson and Pollock skinfold-thickness equations to evaluate each equation's validity and precision. Data from 681 healthy, white adults were used. Percentage body fat (%BF) values were calculated by using the 4-compartment model. The cohort was then divided into validation and cross-validation groups. Equations were developed by using regression analyses and the 4-compartment model. All equations were then tested by using the cross-validation group. Tests for accuracy included mean differences, R(2), and Bland-Altman plots. Precision was evaluated by comparing root mean squared errors. Our new equations' estimated means for %BF in men and women (22.7% and 32.6%, respectively) were closest to the corresponding 4-compartment values (22.8% and 32.8%). The Durnin and Womersley equation means in men and women (20.0% and 31.0%, respectively) and the Jackson and Pollock mean in women (26.2%) underestimated %BF. All equations showed a tendency toward underestimation in subjects with higher %BF. Bland-Altman plots showed limited agreement between Durnin and Wormersley, Jackson and Pollock, and the 4-compartment model. Precision was similar among all the equations. We developed accurate and precise skinfold-thickness equations by using a 4-compartment model as the method of reference. Additionally, we found that the skinfold-thickness equations frequently used by clinicians and practitioners underestimate %BF.

  13. Validation of vertical refractivity profiles as required for performance prediction of coastal surveillance radars

    CSIR Research Space (South Africa)

    Naicker, K

    2011-04-01

    Full Text Available for modeling the detection performance of coastal surveillance radars. Validation is provided through meteorological and radio wave propagation measurements undertaken in False Bay, South Africa. Keywords-vertical refractive profiles, evaporation ducts.... An atmospheric duct is a horizontal layer in troposphere, where the refractive conditions are such that an EM wave will be channeled or guided as discussed above. This results in EM wave propagation over great ranges. In a littoral environment, evaporation...

  14. Predicting resistance to stress : incremental validity of trait emotional intelligence over alexithymia and optimism

    OpenAIRE

    Mikolajczak, Moïra; Luminet, Olivier; Menil, Clementine

    2006-01-01

    As trait emotional intelligence [TEI] is claimed to facilitate adaptation, study 1 (N= 80) investigated whether TEI would be associated with adaptative outcomes such as enhanced self-reported mental and physical health. As these assumptions were supported, study 2 (N= 75) tested the hypothesis of a moderating effect of TEI on the relationship between stress and psychological and somatic health. Incremental validity of TEI over alexithymia and optimism was also examined. We chose academic exam...

  15. Development and validation of a prediction model for long-term sickness absence based on occupational health survey variables

    DEFF Research Database (Denmark)

    Roelen, Corné; Thorsen, Sannie; Heymans, Martijn

    2016-01-01

    Purpose: The purpose of this study is to develop and validate a prediction model for identifying employees at increased risk of long-term sickness absence (LTSA), by using variables commonly measured in occupational health surveys. Materials and methods: Based on the literature, 15 predictor...... and then validated in a sample of 2524 DANES participants, not included in the development sample. Identification of employees at increased LTSA risk was investigated by receiver operating characteristic (ROC) analysis; the area-under-the-ROC-curve (AUC) reflected discrimination between employees with and without...... LTSA during follow-up. Results: The 15-predictor model was reduced to a 9-predictor model including age, gender, education, self-rated health, mental health, prior LTSA, work ability, emotional job demands, and recognition by the management. Discrimination by the 9-predictor model was significant (AUC...

  16. Semi-empirical correction of ab initio harmonic properties by scaling factors: a validated uncertainty model for calibration and prediction

    CERN Document Server

    Pernot, Pascal

    2010-01-01

    Bayesian Model Calibration is used to revisit the problem of scaling factor calibration for semi-empirical correction of ab initio harmonic properties (e.g. vibrational frequencies and zero-point energies). A particular attention is devoted to the evaluation of scaling factor uncertainty, and to its effect on the accuracy of scaled properties. We argue that in most cases of interest the standard calibration model is not statistically valid, in the sense that it is not able to fit experimental calibration data within their uncertainty limits. This impairs any attempt to use the results of the standard model for uncertainty analysis and/or uncertainty propagation. We propose to include a stochastic term in the calibration model to account for model inadequacy. This new model is validated in the Bayesian Model Calibration framework. We provide explicit formulae for prediction uncertainty in typical limit cases: large and small calibration sets of data with negligible measurement uncertainty, and datasets with la...

  17. Predictive accuracy of the PanCan lung cancer risk prediction model - external validation based on CT from the Danish Lung Cancer Screening Trial

    Energy Technology Data Exchange (ETDEWEB)

    Winkler Wille, Mathilde M.; Dirksen, Asger [Gentofte Hospital, Department of Respiratory Medicine, Hellerup (Denmark); Riel, Sarah J. van; Jacobs, Colin; Scholten, Ernst T.; Ginneken, Bram van [Radboud University Medical Center, Department of Radiology and Nuclear Medicine, Nijmegen (Netherlands); Saghir, Zaigham [Herlev Hospital, Department of Respiratory Medicine, Herlev (Denmark); Pedersen, Jesper Holst [Copenhagen University Hospital, Department of Thoracic Surgery, Rigshospitalet, Koebenhavn Oe (Denmark); Hohwue Thomsen, Laura [Hvidovre Hospital, Department of Respiratory Medicine, Hvidovre (Denmark); Skovgaard, Lene T. [University of Copenhagen, Department of Biostatistics, Koebenhavn Oe (Denmark)

    2015-10-15

    Lung cancer risk models should be externally validated to test generalizability and clinical usefulness. The Danish Lung Cancer Screening Trial (DLCST) is a population-based prospective cohort study, used to assess the discriminative performances of the PanCan models. From the DLCST database, 1,152 nodules from 718 participants were included. Parsimonious and full PanCan risk prediction models were applied to DLCST data, and also coefficients of the model were recalculated using DLCST data. Receiver operating characteristics (ROC) curves and area under the curve (AUC) were used to evaluate risk discrimination. AUCs of 0.826-0.870 were found for DLCST data based on PanCan risk prediction models. In the DLCST, age and family history were significant predictors (p = 0.001 and p = 0.013). Female sex was not confirmed to be associated with higher risk of lung cancer; in fact opposing effects of sex were observed in the two cohorts. Thus, female sex appeared to lower the risk (p = 0.047 and p = 0.040) in the DLCST. High risk discrimination was validated in the DLCST cohort, mainly determined by nodule size. Age and family history of lung cancer were significant predictors and could be included in the parsimonious model. Sex appears to be a less useful predictor. (orig.)

  18. Acoustic Prediction Methodology and Test Validation for an Efficient Low-Noise Hybrid Wing Body Subsonic Transport

    Science.gov (United States)

    Kawai, Ronald T. (Compiler)

    2011-01-01

    This investigation was conducted to: (1) Develop a hybrid wing body subsonic transport configuration with noise prediction methods to meet the circa 2007 NASA Subsonic Fixed Wing (SFW) N+2 noise goal of -52 dB cum relative to FAR 36 Stage 3 (-42 dB cum re: Stage 4) while achieving a -25% fuel burned compared to current transports (re :B737/B767); (2) Develop improved noise prediction methods for ANOPP2 for use in predicting FAR 36 noise; (3) Design and fabricate a wind tunnel model for testing in the LaRC 14 x 22 ft low speed wind tunnel to validate noise predictions and determine low speed aero characteristics for an efficient low noise Hybrid Wing Body configuration. A medium wide body cargo freighter was selected to represent a logical need for an initial operational capability in the 2020 time frame. The Efficient Low Noise Hybrid Wing Body (ELNHWB) configuration N2A-EXTE was evolved meeting the circa 2007 NRA N+2 fuel burn and noise goals. The noise estimates were made using improvements in jet noise shielding and noise shielding prediction methods developed by UC Irvine and MIT. From this the Quiet Ultra Integrated Efficient Test Research Aircraft #1 (QUIET-R1) 5.8% wind tunnel model was designed and fabricated.

  19. Validation of predictive equations for basal metabolic rate in eutrophic and obese subjects

    Directory of Open Access Journals (Sweden)

    Renata Lopes Krüger

    2014-12-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n1p73   Prediction equations for basal metabolic rate (BMR continue to be the most common clinical tool for diet prescription; however, the values estimated may differ from those measured by indirect calorimetry (IC, especially in obese subjects. The objective of this study was to determine the BMR of obese and eutrophic subjects by IC, and to compare the results obtained with those estimated by prediction equations in order to identify whether differences exist between predicted values and those measured by IC. Forty men aged 18 to 30 years were evaluated; of these, 20 were grade 1 obese and 20 were eutrophic. The agreement between the prediction equations and IC was evaluated using Bland-Altman (1986 plots. The results showed a variation between the prediction equations and IC of -19.6% to -91% in obese subjects and of 4.2% to 4.4% in eutrophic subjects. In both groups, the Mifflin-St. Jeor equation (1990 was the most accurate, with a difference of -9.1% compared to IC in obese subjects and of 0.9% in eutrophic subjects. This study indicates the Mifflin-St. Jeor equation to be the most adequate to estimate BMR. However, it is important to measure the BMR of obese subjects more accurately and safely in order to establish the best intervention based on physical exercise and healthy eating.

  20. Validation of Framework Code Approach to a Life Prediction System for Fiber Reinforced Composites

    Science.gov (United States)

    Gravett, Phillip

    1997-01-01

    The grant was conducted by the MMC Life Prediction Cooperative, an industry/government collaborative team, Ohio Aerospace Institute (OAI) acted as the prime contractor on behalf of the Cooperative for this grant effort. See Figure I for the organization and responsibilities of team members. The technical effort was conducted during the period August 7, 1995 to June 30, 1996 in cooperation with Erwin Zaretsky, the LERC Program Monitor. Phil Gravett of Pratt & Whitney was the principal technical investigator. Table I documents all meeting-related coordination memos during this period. The effort under this grant was closely coordinated with an existing USAF sponsored program focused on putting into practice a life prediction system for turbine engine components made of metal matrix composites (MMC). The overall architecture of the NMC life prediction system was defined in the USAF sponsored program (prior to this grant). The efforts of this grant were focussed on implementing and tailoring of the life prediction system, the framework code within it and the damage modules within it to meet the specific requirements of the Cooperative. T'he tailoring of the life prediction system provides the basis for pervasive and continued use of this capability by the industry/government cooperative. The outputs of this grant are: 1. Definition of the framework code to analysis modules interfaces, 2. Definition of the interface between the materials database and the finite element model, and 3. Definition of the integration of the framework code into an FEM design tool.

  1. Verification and process oriented validation of the MiKlip decadal prediction system

    Directory of Open Access Journals (Sweden)

    Frank Kaspar

    2016-12-01

    Full Text Available Decadal prediction systems are designed to become a valuable tool for decision making in different sectors of economy, administration or politics. Progress in decadal predictions is also expected to improve our scientific understanding of the climate system. The German Federal Ministry for Education and Research (BMBF therefore funds the German national research project MiKlip (Mittelfristige Klimaprognosen. A network of German research institutions contributes to the development of the system by conducting individual research projects. This special issue presents a collection of papers with results of the evaluation activities within the first phase of MiKlip. They document the improvements of the MiKlip decadal prediction system which were achieved during the first phase. Key aspects are the role of initialization strategies, model resolution or ensemble size. Additional topics are the evaluation of specific weather parameters in selected regions and the use of specific observational datasets for the evaluation.

  2. Visuomotor adaptation needs a validation of prediction error by feedback error

    Directory of Open Access Journals (Sweden)

    Valérie eGaveau

    2014-11-01

    Full Text Available The processes underlying short-term plasticity induced by visuomotor adaptation to a shifted visual field are still debated. Two main sources of error can induce motor adaptation: reaching feedback errors, which correspond to visually perceived discrepancies between hand and target positions, and errors between predicted and actual visual reafferences of the moving hand. These two sources of error are closely intertwined and difficult to disentangle, as both the target and the reaching limb are simultaneously visible. Accordingly, the goal of the present study was to clarify the relative contributions of these two types of errors during a pointing task under prism-displaced vision. In ‘terminal feedback error’ condition, viewing of their hand by subjects was allowed only at movement end, simultaneously with viewing of the target. In ‘movement prediction error’ condition, viewing of the hand was limited to movement duration, in the absence of any visual target, and error signals arose solely from comparisons between predicted and actual reafferences of the hand. In order to prevent intentional corrections of errors, a subthreshold, progressive stepwise increase in prism deviation was used, so that subjects remained unaware of the visual deviation applied in both conditions. An adaptive aftereffect was observed in the ‘terminal feedback error’ condition only. As far as subjects remained unaware of the optical deviation and self-assigned pointing errors, prediction error alone was insufficient to induce adaptation. These results indicate a critical role of hand-to-target feedback error signals in visuomotor adaptation; consistent with recent neurophysiological findings, they suggest that a combination of feedback and prediction error signals is necessary for eliciting aftereffects. They also suggest that feedback error updates the prediction of reafferences when a visual perturbation is introduced gradually and cognitive factors are

  3. Cross-Validation of Age-Predicted Maximal Heart Rate Equations Among Female Collegiate Athletes.

    Science.gov (United States)

    Esco, Michael R; Chamberlain, Nik; Flatt, Andrew A; Snarr, Ronald L; Bishop, Phillip A; Williford, Henry N

    2015-11-01

    The purpose of this study was to determine the accuracy of 3 general and 2 female-specific age-predicted maximal heart rate (HRmax) prediction equations in female collegiate athletes. Thirty female collegiate athletes (age = 21.5 ± 1.9 years, height = 164.7 ± 6.6 cm, weight = 61.3 ± 8.2 kg) participated. HRmax was determined with a maximal graded exercise test and predicted with 3 general equations (Fox et al., Astrand, and Tanaka et al.) and 2 female-specific equations (Fairbarn et al. and Gulati et al.). There was no significant difference between observed HRmax (185.9 ± 5.0 b·min) and the Fairbarn (187.5 ± 1.2 b·min) and Gulati (187.1 ± 1.7 b·min) equations (p = 0.11 and 0.23, respectively). The Fox (198.5 ± 1.9 b·min), Astrand (198.1 ± 1.6 b·min), and Tanaka (193.0 ± 1.4 b·min) equations provided significantly higher estimates compared with observed HRmax (p < 0.001 for each). The standard error of the estimate was similar for all the prediction equations (between 5.0 and 5.4 b·min), but the total error was smallest for Fairbarn and Gulati (5.3 b·min for each) and largest for Fox and Astrand (13.9 and 13.3 b·min, respectively). The 95% limits of agreement of the mean error were similar for all of the prediction equations, with values varying between 9.9 and 10.5 b·min. Because of the wide limits of agreement displayed by each equation, the use of age-predicted methods for estimating HRmax in collegiate female athletes should be performed only with caution.

  4. The fitness landscape of HIV-1 gag: advanced modeling approaches and validation of model predictions by in vitro testing.

    Directory of Open Access Journals (Sweden)

    Jaclyn K Mann

    2014-08-01

    Full Text Available Viral immune evasion by sequence variation is a major hindrance to HIV-1 vaccine design. To address this challenge, our group has developed a computational model, rooted in physics, that aims to predict the fitness landscape of HIV-1 proteins in order to design vaccine immunogens that lead to impaired viral fitness, thus blocking viable escape routes. Here, we advance the computational models to address previous limitations, and directly test model predictions against in vitro fitness measurements of HIV-1 strains containing multiple Gag mutations. We incorporated regularization into the model fitting procedure to address finite sampling. Further, we developed a model that accounts for the specific identity of mutant amino acids (Potts model, generalizing our previous approach (Ising model that is unable to distinguish between different mutant amino acids. Gag mutation combinations (17 pairs, 1 triple and 25 single mutations within these predicted to be either harmful to HIV-1 viability or fitness-neutral were introduced into HIV-1 NL4-3 by site-directed mutagenesis and replication capacities of these mutants were assayed in vitro. The predicted and measured fitness of the corresponding mutants for the original Ising model (r = -0.74, p = 3.6×10-6 are strongly correlated, and this was further strengthened in the regularized Ising model (r = -0.83, p = 3.7×10-12. Performance of the Potts model (r = -0.73, p = 9.7×10-9 was similar to that of the Ising model, indicating that the binary approximation is sufficient for capturing fitness effects of common mutants at sites of low amino acid diversity. However, we show that the Potts model is expected to improve predictive power for more variable proteins. Overall, our results support the ability of the computational models to robustly predict the relative fitness of mutant viral strains, and indicate the potential value of this approach for understanding viral immune evasion

  5. Validation of Delft3D as a Coastal Surge and Inundation Prediction System

    Science.gov (United States)

    2016-04-07

    modeling system Delft3D that includes surge and inundation prediction. We have developed a GUI based on the Delft DashBoard tool that helps process ...predictions. 1.2 Delft3d modeling suite The Delft3D suite of models is a fully integrated software suite for 2-dimensional (2D) and 3- dimensional (3D... Engineering , 73, 58-70. Booij, N., R. Ris and L. Holthuijsen, 1999. A third-generation wave model for coastal regions, Part I, Model description and

  6. Validation of a Model for Prediction of Host Damage by Two Nematode Species

    OpenAIRE

    Duncan, Larry W.; Ferris, Howard

    1983-01-01

    Plant roots were mechanically injured or subjected to nematode parasitism to test the model of host damage by two nematode species: y = m' + (l - m')c'z₁P₁₁z₂P₁₂ for y ≤ 1.0 and y = 1.0 for y > 1.0, where m' = m₁ + (m₂ - m₁) (1 - y₂)/[(1 - y₁) + (l - y₂)] and c' = (z₁-T₁ + z₂-T₂)/2. Damage functions for greenhouse-grown radish plants (cv. Cherry Belle) mechanically injured with small or large steel needles were used to predict growth of plants injured by both needles. Growth predictions accou...

  7. Large-scale validation of methods for cytotoxic T-lymphocyte epitope prediction

    DEFF Research Database (Denmark)

    Larsen, Mette Voldby; Lundegaard, Claus; Lamberth, K.

    2007-01-01

    BACKGROUND: Reliable predictions of Cytotoxic T lymphocyte (CTL) epitopes are essential for rational vaccine design. Most importantly, they can minimize the experimental effort needed to identify epitopes. NetCTL is a web-based tool designed for predicting human CTL epitopes in any given protein....... of the other methods achieved a sensitivity of 0.64. The NetCTL-1.2 method is available at http://www.cbs.dtu.dk/services/NetCTL.All used datasets are available at http://www.cbs.dtu.dk/suppl/immunology/CTL-1.2.php....

  8. Large-scale validation of methods for cytotoxic T-lymphocyte epitope prediction

    DEFF Research Database (Denmark)

    Larsen, Mette Voldby; Lundegaard, Claus; Lamberth, K.;

    2007-01-01

    BACKGROUND: Reliable predictions of Cytotoxic T lymphocyte (CTL) epitopes are essential for rational vaccine design. Most importantly, they can minimize the experimental effort needed to identify epitopes. NetCTL is a web-based tool designed for predicting human CTL epitopes in any given protein....... of the other methods achieved a sensitivity of 0.64. The NetCTL-1.2 method is available at http://www.cbs.dtu.dk/services/NetCTL.All used datasets are available at http://www.cbs.dtu.dk/suppl/immunology/CTL-1.2.php....

  9. Accuracy of Genome-Enabled Prediction in a Dairy Cattle Population using Different Cross-Validation Layouts

    Science.gov (United States)

    Pérez-Cabal, M. Angeles; Vazquez, Ana I.; Gianola, Daniel; Rosa, Guilherme J. M.; Weigel, Kent A.

    2012-01-01

    The impact of extent of genetic relatedness on accuracy of genome-enabled predictions was assessed using a dairy cattle population and alternative cross-validation (CV) strategies were compared. The CV layouts consisted of training and testing sets obtained from either random allocation of individuals (RAN) or from a kernel-based clustering of individuals using the additive relationship matrix, to obtain two subsets that were as unrelated as possible (UNREL), as well as a layout based on stratification by generation (GEN). The UNREL layout decreased the average genetic relationships between training and testing animals but produced similar accuracies to the RAN design, which were about 15% higher than in the GEN setting. Results indicate that the CV structure can have an important effect on the accuracy of whole-genome predictions. However, the connection between average genetic relationships across training and testing sets and the estimated predictive ability is not straightforward, and may depend also on the kind of relatedness that exists between the two subsets and on the heritability of the trait. For high heritability traits, close relatives such as parents and full-sibs make the greatest contributions to accuracy, which can be compensated by half-sibs or grandsires in the case of lack of close relatives. However, for the low heritability traits the inclusion of close relatives is crucial and including more relatives of various types in the training set tends to lead to greater accuracy. In practice, CV designs should resemble the intended use of the predictive models, e.g., within or between family predictions, or within or across generation predictions, such that estimation of predictive ability is consistent with the actual application to be considered. PMID:22403583

  10. Identifying high risk individuals for targeted lung cancer screening: Independent validation of the PLCOm2012 risk prediction tool.

    Science.gov (United States)

    Weber, Marianne; Yap, Sarsha; Goldsbury, David; Manners, David; Tammemagi, Martin; Marshall, Henry; Brims, Fraser; McWilliams, Annette; Fong, Kwun; Kang, Yoon Jung; Caruana, Michael; Banks, Emily; Canfell, Karen

    2017-07-15

    Lung cancer screening with computerised tomography holds promise, but optimising the balance of benefits and harms via selection of a high risk population is critical. PLCOm2012 is a logistic regression model based on U.S. data, incorporating sociodemographic and health factors, which predicts 6-year lung cancer risk among ever-smokers, and thus may better predict those who might benefit from screening than criteria based solely on age and smoking history. We aimed to validate the performance of PLCOm2012 in predicting lung cancer outcomes in a cohort of Australian smokers. Predicted risk of lung cancer was calculated using PLCOm2012 applied to baseline data from 95,882 ever-smokers aged ≥45 years in the 45 and Up Study (2006-2009). Predictions were compared to lung cancer outcomes captured to June 2014 via linkage to population-wide health databases; a total of 1,035 subsequent lung cancer diagnoses were identified. PLCOm2012 had good discrimination (area under the receiver-operating-characteristic-curve; AUC 0.80, 95%CI 0.78-0.81) and excellent calibration (mean and 90th percentiles of absolute risk difference between observed and predicted outcomes: 0.006 and 0.016, respectively). Sensitivity (69.4%, 95%CI, 65.6-73.0%) of the PLCOm2012 criteria in the 55-74 year age group for predicting lung cancers was greater than that using criteria based on ≥30 pack-years smoking and ≤15 years quit (57.3%, 53.3-61.3%; p cancer screening using PLCOm2012 might improve the balance of benefits versus harms, and cost-effectiveness of lung cancer screening. © 2017 UICC.

  11. Social learning and the replication process: an experimental investigation.

    Science.gov (United States)

    Derex, Maxime; Feron, Romain; Godelle, Bernard; Raymond, Michel

    2015-06-07

    Human cultural traits typically result from a gradual process that has been described as analogous to biological evolution. This observation has led pioneering scholars to draw inspiration from population genetics to develop a rigorous and successful theoretical framework of cultural evolution. Social learning, the mechanism allowing information to be transmitted between individuals, has thus been described as a simple replication mechanism. Although useful, the extent to which this idealization appropriately describes the actual social learning events has not been carefully assessed. Here, we used a specifically developed computer task to evaluate (i) the extent to which social learning leads to the replication of an observed behaviour and (ii) the consequences it has for fitness landscape exploration. Our results show that social learning does not lead to a dichotomous choice between disregarding and replicating social information. Rather, it appeared that individuals combine and transform information coming from multiple sources to produce new solutions. As a consequence, landscape exploration was promoted by the use of social information. These results invite us to rethink the way social learning is commonly modelled and could question the validity of predictions coming from models considering this process as replicative.

  12. Prediction and validation of buckling stress (σcrt of the ceramic honeycomb cell walls under quasi-static compression

    Directory of Open Access Journals (Sweden)

    Pandu Ramavath

    2016-12-01

    Full Text Available Alumina- and cordierite-based honeycombs with varying relative densities were extruded and sintered at the respective sintering temperatures. Solid samples are also prepared under identical conditions and flexural strength (σf was estimated by three-point bend measurements. Buckling stress of honeycombs are predicted based on σf using standard equations and validated with quasi-static compression test along the channels of honeycombs with varying relative densities. The discrepancy observed on calculated and measured values is correlated with the pre-existing flaws indicating the criticality in close control of processing parameters.

  13. Predicting sex offender recidivism. I. Correcting for item overselection and accuracy overestimation in scale development. II. Sampling error-induced attenuation of predictive validity over base rate information.

    Science.gov (United States)

    Vrieze, Scott I; Grove, William M

    2008-06-01

    The authors demonstrate a statistical bootstrapping method for obtaining unbiased item selection and predictive validity estimates from a scale development sample, using data (N = 256) of Epperson et al. [2003 Minnesota Sex Offender Screening Tool-Revised (MnSOST-R) technical paper: Development, validation, and recommended risk level cut scores. Retrieved November 18, 2006 from Iowa State University Department of Psychology web site: http://www.psychology.iastate.edu/ approximately dle/mnsost_download.htm] from which the Minnesota Sex Offender Screening Tool-Revised (MnSOST-R) was developed. Validity (area under receiver operating characteristic curve) reported by Epperson et al. was .77 with 16 items selected. The present analysis yielded an asymptotically unbiased estimator AUC = .58. The present article also focused on the degree to which sampling error renders estimated cutting scores (appropriate to local [varying] recidivism base rates) nonoptimal, so that the long-run performance (measured by correct fraction, the total proportion of correct classifications) of these estimated cutting scores is poor, when they are applied to their parent populations (having assumed values for AUC and recidivism rate). This was investigated by Monte Carlo simulation over a range of AUC and recidivism rate values. Results indicate that, except for the AUC values higher than have ever been cross-validated, in combination with recidivism base rates severalfold higher than the literature average [Hanson and Morton-Bourgon, 2004, Predictors of sexual recidivism: An updated meta-analysis. (User report 2004-02.). Ottawa: Public Safety and Emergency Preparedness Canada], the user of an instrument similar in performance to the MnSOST-R cannot expect to achieve correct fraction performance notably in excess of what is achievable from knowing the population recidivism rate alone. The authors discuss the legal implications of their findings for procedural and substantive due process in

  14. Replication Restart in Bacteria.

    Science.gov (United States)

    Michel, Bénédicte; Sandler, Steven J

    2017-07-01

    In bacteria, replication forks assembled at a replication origin travel to the terminus, often a few megabases away. They may encounter obstacles that trigger replisome disassembly, rendering replication restart from abandoned forks crucial for cell viability. During the past 25 years, the genes that encode replication restart proteins have been identified and genetically characterized. In parallel, the enzymes were purified and analyzed in vitro, where they can catalyze replication initiation in a sequence-independent manner from fork-like DNA structures. This work also revealed a close link between replication and homologous recombination, as replication restart from recombination intermediates is an essential step of DNA double-strand break repair in bacteria and, conversely, arrested replication forks can be acted upon by recombination proteins and converted into various recombination substrates. In this review, we summarize this intense period of research that led to the characterization of the ubiquitous replication restart protein PriA and its partners, to the definition of several replication restart pathways in vivo, and to the description of tight links between replication and homologous recombination, responsible for the importance of replication restart in the maintenance of genome stability. Copyright © 2017 American Society for Microbiology.

  15. A Validated Prediction Model for Overall Survival From Stage III Non-Small Cell Lung Cancer: Toward Survival Prediction for Individual Patients

    Energy Technology Data Exchange (ETDEWEB)

    Oberije, Cary, E-mail: cary.oberije@maastro.nl [Radiation Oncology, Research Institute GROW of Oncology, Maastricht University Medical Center, Maastricht (Netherlands); De Ruysscher, Dirk [Radiation Oncology, Research Institute GROW of Oncology, Maastricht University Medical Center, Maastricht (Netherlands); Universitaire Ziekenhuizen Leuven, KU Leuven (Belgium); Houben, Ruud [Radiation Oncology, Research Institute GROW of Oncology, Maastricht University Medical Center, Maastricht (Netherlands); Heuvel, Michel van de; Uyterlinde, Wilma [Department of Thoracic Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Deasy, Joseph O. [Memorial Sloan Kettering Cancer Center, New York (United States); Belderbos, Jose [Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Dingemans, Anne-Marie C. [Department of Pulmonology, University Hospital Maastricht, Research Institute GROW of Oncology, Maastricht (Netherlands); Rimner, Andreas; Din, Shaun [Memorial Sloan Kettering Cancer Center, New York (United States); Lambin, Philippe [Radiation Oncology, Research Institute GROW of Oncology, Maastricht University Medical Center, Maastricht (Netherlands)

    2015-07-15

    Purpose: Although patients with stage III non-small cell lung cancer (NSCLC) are homogeneous according to the TNM staging system, they form a heterogeneous group, which is reflected in the survival outcome. The increasing amount of information for an individual patient and the growing number of treatment options facilitate personalized treatment, but they also complicate treatment decision making. Decision support systems (DSS), which provide individualized prognostic information, can overcome this but are currently lacking. A DSS for stage III NSCLC requires the development and integration of multiple models. The current study takes the first step in this process by developing and validating a model that can provide physicians with a survival probability for an individual NSCLC patient. Methods and Materials: Data from 548 patients with stage III NSCLC were available to enable the development of a prediction model, using stratified Cox regression. Variables were selected by using a bootstrap procedure. Performance of the model was expressed as the c statistic, assessed internally and on 2 external data sets (n=174 and n=130). Results: The final multivariate model, stratified for treatment, consisted of age, gender, World Health Organization performance status, overall treatment time, equivalent radiation dose, number of positive lymph node stations, and gross tumor volume. The bootstrapped c statistic was 0.62. The model could identify risk groups in external data sets. Nomograms were constructed to predict an individual patient's survival probability ( (www.predictcancer.org)). The data set can be downloaded at (https://www.cancerdata.org/10.1016/j.ijrobp.2015.02.048). Conclusions: The prediction model for overall survival of patients with stage III NSCLC highlights the importance of combining patient, clinical, and treatment variables. Nomograms were developed and validated. This tool could be used as a first building block for a decision support system.

  16. Experimental Validation of Energy Resources Integration in Microgrids via Distributed Predictive Control

    DEFF Research Database (Denmark)

    Mantovani, Giancarlo; Costanzo, Giuseppe Tommaso; Marinelli, Mattia

    2014-01-01

    This paper presents an innovative control scheme for the management of energy consumption in commercial build- ings with local energy production, such as photovoltaic panels or wind turbine and an energy storage unit. The presented scheme is based on distributed model predictive controllers, which...

  17. Cross-Validation of a Predictive Screening Test for Children with Articulatory Speech Defects. Final Report.

    Science.gov (United States)

    Van Riper, Charles; Erickson, Robert

    To determine the accuracy with which the 47-item Predictive Screening Test of Articulation (PSTA) is able to identify first grade children who will master their articulation errors without speech therapy by the time they enter third grade, two groups of children were studied who were deficient enough in speech to be enrolled in therapy, but had no…

  18. Conscientiousness at the workplace: Applying mixture IRT to investigate scalability and predictive validity

    NARCIS (Netherlands)

    Egberink, I.J.L.; Meijer, R.R.; Veldkamp, Bernard P.

    2010-01-01

    Mixture item response theory (IRT) models have been used to assess multidimensionality of the construct being measured and to detect different response styles for different groups. In this study a mixture version of the graded response model was applied to investigate scalability and predictive

  19. Conscientiousness in the workplace : Applying mixture IRT to investigate scalability and predictive validity

    NARCIS (Netherlands)

    Egberink, I.J.L.; Meijer, R.R.; Veldkamp, B.P.

    Mixture item response theory (IRT) models have been used to assess multidimensionality of the construct being measured and to detect different response styles for different groups. In this study a mixture version of the graded response model was applied to investigate scalability and predictive

  20. Chemotherapy effectiveness and mortality prediction in surgically treated osteosarcoma dogs : A validation study

    NARCIS (Netherlands)

    Schmidt, A. F.; Nielen, M.; Withrow, S. J.; Selmic, L. E.; Burton, J. H.; Klungel, O. H.; Groenwold, R. H H; Kirpensteijn, J.

    2016-01-01

    Canine osteosarcoma is the most common bone cancer, and an important cause of mortality and morbidity, in large purebred dogs. Previously we constructed two multivariable models to predict a dog's 5-month or 1-year mortality risk after surgical treatment for osteosarcoma. According to the 5-month mo

  1. Validation of a base deficit-based trauma prediction model and comparison with TRISS and ASCOT

    NARCIS (Netherlands)

    Lam, S. W.; Lingsma, H. F.; van Beeck, E. F.; Leenen, L. P H

    2016-01-01

    Background: Base deficit provides a more objective indicator of physiological stress following injury as compared with vital signs constituting the revised trauma score (RTS). We have previously developed a base deficit-based trauma survival prediction model [base deficit and injury severity score m

  2. External Validation of Prediction Models for Pneumonia in Primary Care Patients with Lower Respiratory Tract Infection

    DEFF Research Database (Denmark)

    Schierenberg, Alwin; Minnaard, Margaretha C; Hopstaken, Rogier M

    2016-01-01

    , representing the performance of an individual model relative to the average dataset performance. Prediction models by van Vugt et al. and Heckerling et al. demonstrated the highest pooled AUC of 0.79 (95% CI 0.74-0.85) and 0.72 (0.68-0.76), respectively. Other models by Diehr et al., Singal et al., Melbye et...

  3. An Other Perspective on Personality: Meta-Analytic Integration of Observers' Accuracy and Predictive Validity

    Science.gov (United States)

    Connelly, Brian S.; Ones, Deniz S.

    2010-01-01

    The bulk of personality research has been built from self-report measures of personality. However, collecting personality ratings from other-raters, such as family, friends, and even strangers, is a dramatically underutilized method that allows better explanation and prediction of personality's role in many domains of psychology. Drawing…

  4. Predicting major outcomes in type 1 diabetes: a model development and validation study

    NARCIS (Netherlands)

    Soedamah-Muthu, S.S.; Vergouwe, Y.; Costacou, T.; Miller, R.G.; Zgibor, J.; Chaturvedi, N.; Snell-Bergeon, J.K.; Maahs, D.M.; Rewers, M.; Forsblom, C.; Harjutsalo, V.; Groop, P.H.; Fuller, J.H.; Moons, K.G.M.; Orchard, T.J.

    2014-01-01

    Aims/hypothesis Type 1 diabetes is associated with a higher risk of major vascular complications and death. A reliable method that predicted these outcomes early in the disease process would help in risk classification. We therefore developed such a prognostic model and quantified its performance in

  5. Predictive validity of adult risk assessment tools with juveniles who offended sexually.

    Science.gov (United States)

    Ralston, Christopher A; Epperson, Douglas L

    2013-09-01

    An often-held assumption in the area of sexual recidivism risk assessment is that different tools should be used for adults and juveniles. This assumption is driven either by the observation that adolescents tend to be in a constant state of flux in the areas of development, education, and social structure or by the fact that the judicial system recognizes that juveniles and adults are different. Though the assumption is plausible, it is largely untested. The present study addressed this issue by scoring 2 adult sexual offender risk assessment tools, the Minnesota Sex Offender Screening Tool-Revised and the Static-99, on an exhaustive sample (N = 636) of juveniles who had sexually offended (JSOs) in Utah. For comparison, 2 tools designed for JSOs were also scored: the Juvenile-Sex Offender Assessment Protocol-II and the Juvenile Risk Assessment Scale. Recidivism data were collected for 2 time periods: before age 18 (sexual, violent, any recidivism) and from age 18 to the year 2004 (sexual). The adult actuarial risk assessment tools predicted all types of juvenile recidivism significantly and at approximately the same level of accuracy as juvenile-specific tools. However, the accuracy of longer term predictions of adult sexual recidivism across all 4 tools was substantially lower than the accuracy achieved in predicting juvenile sexual recidivism, with 2 of the tools producing nonsignificant results, documenting the greater difficulty in making longer term predictions on the basis of adolescent behavior.

  6. Conscientiousness in the workplace : Applying mixture IRT to investigate scalability and predictive validity

    NARCIS (Netherlands)

    Egberink, I.J.L.; Meijer, R.R.; Veldkamp, B.P.

    2010-01-01

    Mixture item response theory (IRT) models have been used to assess multidimensionality of the construct being measured and to detect different response styles for different groups. In this study a mixture version of the graded response model was applied to investigate scalability and predictive vali

  7. Conscientiousness in the workplace: Applying mixture IRT to investigate scalability and predictive validity

    NARCIS (Netherlands)

    Egberink, Iris J.L.; Meijer, Rob R.; Veldkamp, Bernard P.

    2010-01-01

    Mixture item response theory (IRT) models have been used to assess multidimensionality of the construct being measured and to detect different response styles for different groups. In this study a mixture version of the graded response model was applied to investigate scalability and predictive vali

  8. The Prediction of Paranoid Behavior: Comparative Validities of Obvious vs. Subtle MMPI Paranoia (Pa) Items.

    Science.gov (United States)

    Hovanitz, Christine A.; And Others

    1983-01-01

    Investigated the relationship between the Minnesota Multiphasic Personality Inventory paranoia subtle, neutral, and obvious subscales and criteria presumed to reflect various paranoid characteristics in a sample of male college students (N=100). Results showed that both the obvious and subtle Pa Items predicted various criteria. (Author/JAC)

  9. The Nature and Predictive Validity of a Benchmark Assessment Program in an American Indian School District

    Science.gov (United States)

    Payne, Beverly J. R.

    2013-01-01

    This mixed methods study explored the nature of a benchmark assessment program and how well the benchmark assessments predicted End-of-Grade (EOG) and End-of-Course (EOC) test scores in an American Indian school district. Five major themes were identified and used to develop a Dimensions of Benchmark Assessment Program Effectiveness model:…

  10. Validation of a base deficit-based trauma prediction model and comparison with TRISS and ASCOT

    NARCIS (Netherlands)

    Lam, S. W.; Lingsma, H. F.; van Beeck, E. F.; Leenen, L. P H

    2016-01-01

    Background: Base deficit provides a more objective indicator of physiological stress following injury as compared with vital signs constituting the revised trauma score (RTS). We have previously developed a base deficit-based trauma survival prediction model [base deficit and injury severity score

  11. Validity of predictive equations for resting energy expenditure in Belgian normal weight to morbid obese women

    NARCIS (Netherlands)

    Weijs, J.M. Peter; Vansant, A.A.M. Greet

    2010-01-01

    Background & aims: Individual energy requirements of overweight and obese adults can often not be measured by indirect calorimetry, mainly due to the time-consuming procedure and the high costs. To analyze which resting energy expenditure(REE)predictive equation is the best alternative for indirect

  12. Validity of the Clock Drawing Test in predicting reports of driving problems in the elderly

    Directory of Open Access Journals (Sweden)

    Banou Evangelia

    2004-10-01

    Full Text Available Abstract Background This study examined the use of the Folstein Mini Mental Status Exam (MMSE and the Clock Drawing Test (CDT in predicting retrospective reports of driving problems among the elderly. The utility of existing scoring systems for the CDT was also examined. Methods Archival chart records of 325 patients of a geriatric outpatient clinic were reviewed, of which 162 had CDT results (including original clock drawings. T-test, correlation, and regression procedures were used to analyze the data. Results Both CDT and MMSE scores were significantly worse among non-drivers than individuals who were currently or recently driving. Among current or recent drivers, scores on both instruments correlated significantly with the total number of reported accidents or near misses, although the magnitude of the respective correlations was small. Only MMSE scores, however, significantly predicted whether or not any accidents or near misses were reported at all. Neither MMSE nor CDT scores predicted unique variance in the regressions. Conclusions The overall results suggest that both the MMSE and CDT have limited utility as potential indicators of driving problems in the elderly. The demonstrated predictive power for these instruments appears to be redundant, such that both appear to assess general cognitive function versus more specific abilities. Furthermore, the lack of robust prediction suggests that neither are sufficient to serve as stand-alone instruments on which to solely base decisions of driving capacity. Rather, individuals who evidence impairment should be provided a more thorough and comprehensive assessment than can be obtained through screening tools.

  13. Structure simulation in unidirectionally solidified turbine blade by dendrite envelope tracking model (Ⅱ): model validation and defects prediction

    Institute of Scientific and Technical Information of China (English)

    WANG Tong-min; SU Yan-qing; GUO Jing-jie; I. OHNAKA; H. YASUDA

    2006-01-01

    The developed model was validated by the checking of grain preferential growth orientation and the solidification experiment with low melting point alloy of Sn-21%Bi(mole fraction). It was also applied to predict the structure defects (e.g. stray grain) of unidirectionally solidified turbine blade. The results show that the developed model is reliable and has the following abilities: 1) reduce the misorientation caused by the orthogonal mesh used in simulation; 2) well reproduce the growth competition among the different-preferential-direction grains with less than 10% relative error; 3) predict the structure defect of stray grain with the accuracy over 80%; 4) optimize the grain selector to better obtain a single crystal avoiding the multigrain defect; 5) simulate the structure evolution (nucleation and growth) of the directional and single crystal turbine blade.

  14. A BEM approach to validate a model for predicting sound propagation over non-flat terrain

    DEFF Research Database (Denmark)

    Quirós Alpera, Susana; Jacobsen, Finn; Juhl, Peter Møller

    2003-01-01

    A two-dimensional boundary element model for sound propagation in a homogeneous atmosphere above non-flat terrain has been constructed. An infinite impedance plane is taken into account in the Green's function in the underlying integral equation, so that only the nonflat parts of the terrain need....... Sound Vibrat. 223 (1999) 355]. The resulting BEM model, which can handle arbitrary combinations of barriers and hollows, has been used for validating a ray model for various difficult configurations, including combinations of valleys and barriers. (C) 2003 Elsevier Science Ltd. All rights reserved....

  15. A BEM approach to validate a model for predicting sound propagation over non-flat terrain

    DEFF Research Database (Denmark)

    Quirósy Alpera, S.; Jacobsen, Finn; Juhl, P.M.

    2003-01-01

    A two-dimensional boundary element model for sound propagation in a homogeneous atmosphere above non-flat terrain has been constructed. An infinite impedance plane is taken into account in the Green's function in the underlying integral equation, so that only the nonflat parts of the terrain need....... Sound Vibrat. 223 (1999) 355]. The resulting BEM model, which can handle arbitrary combinations of barriers and hollows, has been used for validating a ray model for various difficult configurations, including combinations of valleys and barriers....

  16. The validity of Iran’s national university entrance examination (Konkoor for predicting medical students’ academic performance

    Directory of Open Access Journals (Sweden)

    Farrokhi-Khajeh-Pasha Yasin

    2012-07-01

    Full Text Available Abstract Background In Iran, admission to medical school is based solely on the results of the highly competitive, nationwide Konkoor examination. This paper examines the predictive validity of Konkoor scores, alone and in combination with high school grade point averages (hsGPAs, for the academic performance of public medical school students in Iran. Methods This study followed the cohort of 2003 matriculants at public medical schools in Iran from entrance through internship. The predictor variables were Konkoor total and subsection scores and hsGPAs. The outcome variables were (1 Comprehensive Basic Sciences Exam (CBSE scores; (2 Comprehensive Pre-Internship Exam (CPIE scores; and (3 medical school grade point averages (msGPAs for the courses taken before internship. Pearson correlation and regression analyses were used to assess the relationships between the selection criteria and academic performance. Results There were 2126 matriculants (1374 women and 752 men in 2003. Among the outcome variables, the CBSE had the strongest association with the Konkoor total score (r = 0.473, followed by msGPA (r = 0.339 and the CPIE (r = 0.326. While adding hsGPAs to the Konkoor total score almost doubled the power to predict msGPAs (R2 = 0.225, it did not have a substantial effect on CBSE or CPIE prediction. Conclusions The Konkoor alone, and even in combination with hsGPA, is a relatively poor predictor of medical students’ academic performance, and its predictive validity declines over the academic years of medical school. Care should be taken to develop comprehensive admissions criteria, covering both cognitive and non-cognitive factors, to identify the best applicants to become "good doctors" in the future. The findings of this study can be helpful for policy makers in the medical education field.

  17. External validation of the APPS, a new and simple outcome prediction score in patients with the acute respiratory distress syndrome.

    Science.gov (United States)

    Bos, Lieuwe D; Schouten, Laura R; Cremer, Olaf L; Ong, David S Y; Schultz, Marcus J

    2016-12-01

    A recently developed prediction score based on age, arterial oxygen partial pressure to fractional inspired oxygen ratio (PaO2/FiO2) and plateau pressure (abbreviated as 'APPS') was shown to accurately predict mortality in patients diagnosed with the acute respiratory distress syndrome (ARDS). After thorough temporal external validation of the APPS, we tested the spatial external validity in a cohort of ARDS patients recruited during 3 years in two hospitals in the Netherlands. Consecutive patients with moderate or severe ARDS according to the Berlin definition were included in this observational multicenter cohort study from the mixed medical-surgical ICUs of two university hospitals. The APPS was calculated per patient with the maximal airway pressure instead of the plateau pressure as all patients were ventilated in pressure-controlled mode. The predictive accuracy for hospital mortality was evaluated by calculating the area under the receiver operating characteristics curve (AUC-ROC). Additionally, the score was recalibrated and reassessed. In total, 439 patients with moderate or severe ARDS were analyzed. All-cause hospital mortality was 43 %. The APPS predicted all-cause hospital mortality with moderate accuracy, with an AUC-ROC of 0.62 [95 % confidence interval (CI) 0.56-0.67]. Calibration was moderate using the original cutoff values (Hosmer-Lemeshow goodness of fit P APPS was moderate, also after recalibration of the score, and thus the APPS does not seem to be fitted for that purpose. The APPS might serve as simple tool for stratification of mortality in patients with moderate or severe ARDS. Without recalibrations, the performance of the APPS was moderate and we should therefore hesitate to blindly apply the score to other cohorts of ARDS patients.

  18. Validating proposed migration equation and parameters' values as a tool to reproduce and predict (137)Cs vertical migration activity in Spanish soils.

    Science.gov (United States)

    Olondo, C; Legarda, F; Herranz, M; Idoeta, R

    2017-01-05

    This paper shows the procedure performed to validate the migration equation and the migration parameters' values presented in a previous paper (Legarda et al., 2011) regarding the migration of (137)Cs in Spanish mainland soils. In this paper, this model validation has been carried out checking experimentally obtained activity concentration values against those predicted by the model. This experimental data come from the measured vertical activity profiles of 8 new sampling points which are located in northern Spain. Before testing predicted values of the model, the uncertainty of those values has been assessed with the appropriate uncertainty analysis. Once establishing the uncertainty of the model, both activity concentration values, experimental versus model predicted ones, have been compared. Model validation has been performed analyzing its accuracy, studying it as a whole and also at different depth intervals. As a result, this model has been validated as a tool to predict (137)Cs behaviour in a Mediterranean environment.

  19. The predictive utility of neuropsychological symptom validity testing as it relates to psychological presentation.

    Science.gov (United States)

    Zakzanis, Konstantine K; Gammada, Emnet; Jeffay, Eliyas

    2012-01-01

    The present study examined the relationship between multiple neuropsychological symptom validity tests (SVTs) and psychological presentation. More formally, we set out to determine if performance on neuropsychological SVTs was related to psychological symptom credibility and which specific neuropsychological SVTs were most associated with noncredible psychological presentation. Archival records from 106 litigating examinees were utilized in this study. Our results illustrate that neuropsychological SVTs are modestly related to psychological symptom credibility and that specific neuropsychological SVTs are variably associated to this end. We conclude that when multiple, but not independent, neuropsychological SVTs are employed within the context of a neuropsychological examination, they do have clinical utility as it relates to credibility of psychological presentation and these constructs do share variance reciprocally in clinically meaningful ways. When independently employed, however, the observed relationship is modest at best. Hence, to place clinical opinion on firmer scientific grounds within the context of a neuropsychological examination, multiple cognitive SVTs, in hand with psychological test instruments that include validity indexes, are essential to derive opinion that is based on science rather than faith in the instance of litigation when an incentive to manifest disability for the sake of an external reward holds probable.

  20. Analysis and Validation of a Predictive Model for Growth and Death of Aeromonas hydrophila under Modified Atmospheres at Refrigeration Temperatures

    Science.gov (United States)

    Pin, Carmen; Velasco de Diego, Raquel; George, Susan; García de Fernando, Gonzalo D.; Baranyi, József

    2004-01-01

    Specific growth and death rates of Aeromonas hydrophila were measured in laboratory media under various combinations of temperature, pH, and percent CO2 and O2 in the atmosphere. Predictive models were developed from the data and validated by means of observations obtained from (i) seafood experiments set up for this purpose and (ii) the ComBase database (http://www.combase.cc; http://wyndmoor.arserrc.gov/combase/).Two main reasons were identified for the differences between the predicted and observed growth in food: they were the variability of the growth rates in food and the bias of the model predictions when applied to food environments. A statistical method is presented to quantitatively analyze these differences. The method was also used to extend the interpolation region of the model. In this extension, the concept of generalized Z values (C. Pin, G. García de Fernando, J. A. Ordóñez, and J. Baranyi, Food Microbiol. 18:539-545, 2001) played an important role. The extension depended partly on the density of the model-generating observations and partly on the accuracy of extrapolated predictions close to the boundary of the interpolation region. The boundary of the growth region of the organism was also estimated by means of experimental results for growth and death rates. PMID:15240265