A novel genome-information content-based statistic for genome-wide association analysis designed for next-generation sequencing data.

PubMed

Luo, Li; Zhu, Yun; Xiong, Momiao

2012-06-01

The genome-wide association studies (GWAS) designed for next-generation sequencing data involve testing association of genomic variants, including common, low frequency, and rare variants. The current strategies for association studies are well developed for identifying association of common variants with the common diseases, but may be ill-suited when large amounts of allelic heterogeneity are present in sequence data. Recently, group tests that analyze their collective frequency differences between cases and controls shift the current variant-by-variant analysis paradigm for GWAS of common variants to the collective test of multiple variants in the association analysis of rare variants. However, group tests ignore differences in genetic effects among SNPs at different genomic locations. As an alternative to group tests, we developed a novel genome-information content-based statistics for testing association of the entire allele frequency spectrum of genomic variation with the diseases. To evaluate the performance of the proposed statistics, we use large-scale simulations based on whole genome low coverage pilot data in the 1000 Genomes Project to calculate the type 1 error rates and power of seven alternative statistics: a genome-information content-based statistic, the generalized T(2), collapsing method, multivariate and collapsing (CMC) method, individual χ(2) test, weighted-sum statistic, and variable threshold statistic. Finally, we apply the seven statistics to published resequencing dataset from ANGPTL3, ANGPTL4, ANGPTL5, and ANGPTL6 genes in the Dallas Heart Study. We report that the genome-information content-based statistic has significantly improved type 1 error rates and higher power than the other six statistics in both simulated and empirical datasets.

How to read a paper. Statistics for the non-statistician. II: "Significant" relations and their pitfalls.

PubMed Central

Greenhalgh, T.

1997-01-01

It is possible to be seriously misled by taking the statistical competence (and/or the intellectual honesty) of authors for granted. Some common errors committed (deliberately or inadvertently) by the authors of papers are given in the final box. PMID:9277611

Pattern of irritable bowel syndrome and its impact on quality of life in primary health care center attendees, Suez governorate, Egypt

PubMed Central

Abdulmajeed, Ahmed; Rabab, Mohamed A; Sliem, Hamdy A; Hebatallah, Nour Eldein

2011-01-01

Introduction Irritable bowel syndrome (IBS) is one of the most common disorders diagnosed by gastroenterologists and a common cause of general practice visits. Although this disease is not life threatening, patients with IBS seem to be seriously affected in their everyday life. The study was designed to explore the pattern of IBS in clinical practice and the impact on the quality of life. Methods This is a case control descriptive study. 117 individuals were included in this study. Rome II criteria were used for the diagnosis of IBS. Impact of IBS on patient's quality of life was determined by irritable bowel syndrome quality of life (IBS-QOL) questionnaire. Results Prevalence of IBS among the study sample was 34.2%. 10% were IBS-Diarrhea, 37.5% were IBS-Constipation and 52.5% were alternators. There is statistical insignificant relationship between IBS (+) and age while it was a significant relation regarding gender (more common among women 80%). There is statistical significance relationship between IBS (+) on one hand and marital status and occupational status on the other hand. Patients with IBS had statistically significant lower scores for all IBS- QOL domains compared with the control group. Conclusion IBS is a prevalent disorder that affects females more than males and it has significant impacts on work, lifestyle and social well-being. PMID:22145053

Pattern of irritable bowel syndrome and its impact on quality of life in primary health care center attendees, Suez governorate, Egypt.

PubMed

Abdulmajeed, Ahmed; Rabab, Mohamed A; Sliem, Hamdy A; Hebatallah, Nour Eldein

2011-01-01

Irritable bowel syndrome (IBS) is one of the most common disorders diagnosed by gastroenterologists and a common cause of general practice visits. Although this disease is not life threatening, patients with IBS seem to be seriously affected in their everyday life. The study was designed to explore the pattern of IBS in clinical practice and the impact on the quality of life. This is a case control descriptive study. 117 individuals were included in this study. Rome II criteria were used for the diagnosis of IBS. Impact of IBS on patient's quality of life was determined by irritable bowel syndrome quality of life (IBS-QOL) questionnaire. Prevalence of IBS among the study sample was 34.2%. 10% were IBS-Diarrhea, 37.5% were IBS-Constipation and 52.5% were alternators. There is statistical insignificant relationship between IBS (+) and age while it was a significant relation regarding gender (more common among women 80%). There is statistical significance relationship between IBS (+) on one hand and marital status and occupational status on the other hand. Patients with IBS had statistically significant lower scores for all IBS- QOL domains compared with the control group. IBS is a prevalent disorder that affects females more than males and it has significant impacts on work, lifestyle and social well-being.

A Guerilla Guide to Common Problems in ‘Neurostatistics’: Essential Statistical Topics in Neuroscience

PubMed Central

Smith, Paul F.

2017-01-01

Effective inferential statistical analysis is essential for high quality studies in neuroscience. However, recently, neuroscience has been criticised for the poor use of experimental design and statistical analysis. Many of the statistical issues confronting neuroscience are similar to other areas of biology; however, there are some that occur more regularly in neuroscience studies. This review attempts to provide a succinct overview of some of the major issues that arise commonly in the analyses of neuroscience data. These include: the non-normal distribution of the data; inequality of variance between groups; extensive correlation in data for repeated measurements across time or space; excessive multiple testing; inadequate statistical power due to small sample sizes; pseudo-replication; and an over-emphasis on binary conclusions about statistical significance as opposed to effect sizes. Statistical analysis should be viewed as just another neuroscience tool, which is critical to the final outcome of the study. Therefore, it needs to be done well and it is a good idea to be proactive and seek help early, preferably before the study even begins. PMID:29371855

A Guerilla Guide to Common Problems in 'Neurostatistics': Essential Statistical Topics in Neuroscience.

PubMed

Smith, Paul F

2017-01-01

Effective inferential statistical analysis is essential for high quality studies in neuroscience. However, recently, neuroscience has been criticised for the poor use of experimental design and statistical analysis. Many of the statistical issues confronting neuroscience are similar to other areas of biology; however, there are some that occur more regularly in neuroscience studies. This review attempts to provide a succinct overview of some of the major issues that arise commonly in the analyses of neuroscience data. These include: the non-normal distribution of the data; inequality of variance between groups; extensive correlation in data for repeated measurements across time or space; excessive multiple testing; inadequate statistical power due to small sample sizes; pseudo-replication; and an over-emphasis on binary conclusions about statistical significance as opposed to effect sizes. Statistical analysis should be viewed as just another neuroscience tool, which is critical to the final outcome of the study. Therefore, it needs to be done well and it is a good idea to be proactive and seek help early, preferably before the study even begins.

Pathway analysis with next-generation sequencing data.

PubMed

Zhao, Jinying; Zhu, Yun; Boerwinkle, Eric; Xiong, Momiao

2015-04-01

Although pathway analysis methods have been developed and successfully applied to association studies of common variants, the statistical methods for pathway-based association analysis of rare variants have not been well developed. Many investigators observed highly inflated false-positive rates and low power in pathway-based tests of association of rare variants. The inflated false-positive rates and low true-positive rates of the current methods are mainly due to their lack of ability to account for gametic phase disequilibrium. To overcome these serious limitations, we develop a novel statistic that is based on the smoothed functional principal component analysis (SFPCA) for pathway association tests with next-generation sequencing data. The developed statistic has the ability to capture position-level variant information and account for gametic phase disequilibrium. By intensive simulations, we demonstrate that the SFPCA-based statistic for testing pathway association with either rare or common or both rare and common variants has the correct type 1 error rates. Also the power of the SFPCA-based statistic and 22 additional existing statistics are evaluated. We found that the SFPCA-based statistic has a much higher power than other existing statistics in all the scenarios considered. To further evaluate its performance, the SFPCA-based statistic is applied to pathway analysis of exome sequencing data in the early-onset myocardial infarction (EOMI) project. We identify three pathways significantly associated with EOMI after the Bonferroni correction. In addition, our preliminary results show that the SFPCA-based statistic has much smaller P-values to identify pathway association than other existing methods.

Benchmarking can add up for healthcare accounting.

PubMed

Czarnecki, M T

1994-09-01

In 1993, a healthcare accounting and finance benchmarking survey of hospital and nonhospital organizations gathered statistics about key common performance areas. A low response did not allow for statistically significant findings, but the survey identified performance measures that can be used in healthcare financial management settings. This article explains the benchmarking process and examines some of the 1993 study's findings.

Hydrogeology and water quality of glacial-drift aquifers in the Bemidji-Bagley area, Beltrami, Clearwater, Cass, and Hubbard counties, Minnesota

USGS Publications Warehouse

Stark, J.R.; Busch, J.P.; Deters, M.H.

1991-01-01

The Kruskil-Wallis test, a nonparametric that for 12 of the 21 constituents sampled in groups in the unconfined-drift aquifer, a of these constituents and land use was found statistical technique, indicated common in all land-use type relation between the concentration to be statistically significant.

ARTICULATION OF SPEECH SOUNDS OF SERBIAN LANGUAGE IN CHILDREN AGED SIX TO EIGHT.

PubMed

Mihajlović, Biljana; Cvjetićanin, Bojana; Veselinović, Mila; Škrbić, Renata; Mitrović, Slobodan M

2015-01-01

Phonetic and phonological system of the healthy members of one linguistic community is fully formed around 8 yedrs of age. The auditory and articulatory habits are established with age and tend to be more difficult to be upgraded and completed later. The research was done as a cross-sectional study, conducted at the preschool institution "Radosno detinjstvo" and primary school "Branko Radičević" in Novi Sad. It included 66 children of both genders, aged 6 to 8. The quality of articulation was determined according to the Global Articulation Test by working with each child individually. In each individual vowel, plosive, nasal, lateral and fricative, the quality of articulation was statistically significantly better in the first graders compared to the preschool children (p<0.01). In each affricate, except for the sound /ć/, the quality of articulation was statistically significantly better in the first graders than in the preschool children (p<0.01). The quality of articulation of all speech sounds was statistically significantly better in the first graders than in the preschool children (p<0.01). The most common disorder of articulation is distortion, while only substitution and substitution associated with distortion are less common. Omission does not occur in children from 6 to 8 years of age. Girls have slightly better quality of articulation. The articulatory disorders are more common in preschool children than in children who are in the first grade of primary school. The most commonly mispronounced sounds belong to the group of affricates and fricatives.

The effects of commonly used intravitreal steroids on proliferation index of ciliary body-derived mesenchymal stem cells: an in vitro study.

PubMed

Demir, M Necati; Acar, Ugur; Sobaci, Gungor; Pınarlı, Ferda Alpaslan; Erginturk Acar, Damla; Beyazyıldız, Emrullah; Yesilyurt, Ahmet; Delibasi, Tuncay

2016-03-01

To investigate the effects of commonly used intravitreal steroids on survival and proliferation (namely, proliferation index) of ciliary body-derived mesenchymal stem cells (CB-MSC). CB-MSCs were isolated from newborn rats' eye, and they were expanded in the medium. Commonly used intravitreal steroids such as dexamethasone (Dex) and triamcinolone acetonide (TA) were added into the medium at commonly used concentration in clinical practice (0.1 mg/mL) and at lower concentration (0.01 mg/mL). Proliferation indexes of CB-MSCs were analyzed with the xCELLigence system at nine consecutive times (at 3rd, 6th, 21th, 30th, 45th, 60th, 75th, 90th and 100th h). Both TA and Dex at both 0.01 mg/mL and 0.1 mg/mL concentrations had negative effect on proliferation indexes of CB-MSC. Although negative effect of TA on proliferation index of CB-MSC at both concentrations was not statistically significant, statistically significant negative effect of Dex at 0.01 mg/mL concentration started 60th h (p = 0.017) and 0.1 mg/mL concentration started 30th h (p = 0.014). Even therapeutic doses of intravitreal corticosteroid agents might have negative effects on limited numbers of stem cells. Especially, Dex caused statistically significant toxic effects on CB-MSCs even at lower concentrations of those used clinically. These novel findings deserve further in vivo investigations.

New Statistics for Testing Differential Expression of Pathways from Microarray Data

NASA Astrophysics Data System (ADS)

Siu, Hoicheong; Dong, Hua; Jin, Li; Xiong, Momiao

Exploring biological meaning from microarray data is very important but remains a great challenge. Here, we developed three new statistics: linear combination test, quadratic test and de-correlation test to identify differentially expressed pathways from gene expression profile. We apply our statistics to two rheumatoid arthritis datasets. Notably, our results reveal three significant pathways and 275 genes in common in two datasets. The pathways we found are meaningful to uncover the disease mechanisms of rheumatoid arthritis, which implies that our statistics are a powerful tool in functional analysis of gene expression data.

The (mis)reporting of statistical results in psychology journals.

PubMed

Bakker, Marjan; Wicherts, Jelte M

2011-09-01

In order to study the prevalence, nature (direction), and causes of reporting errors in psychology, we checked the consistency of reported test statistics, degrees of freedom, and p values in a random sample of high- and low-impact psychology journals. In a second study, we established the generality of reporting errors in a random sample of recent psychological articles. Our results, on the basis of 281 articles, indicate that around 18% of statistical results in the psychological literature are incorrectly reported. Inconsistencies were more common in low-impact journals than in high-impact journals. Moreover, around 15% of the articles contained at least one statistical conclusion that proved, upon recalculation, to be incorrect; that is, recalculation rendered the previously significant result insignificant, or vice versa. These errors were often in line with researchers' expectations. We classified the most common errors and contacted authors to shed light on the origins of the errors.

Physiological traits of endornavirus-infected and endornavirus-free common bean (Phaseolus vulgaris) cv Black Turtle Soup.

PubMed

Khankhum, S; Valverde, R A

2018-04-01

This study evaluated the physiological traits of eight lines of common bean (Phaseolus vulgaris) cv. Black Turtle Soup, four of which were double-infected with Phaseolus vulgaris endornavirus 1 and Phaseolus vulgaris endornavirus 2, and four of which were endornavirus-free. Plants from all eight lines were morphologically similar and did not show statistically significant differences in plant height, wet weight, number of days to flowering and pod formation, pods per plant, pod thickness, seed size, number of seeds per pod, and anthocyanin content. However, the endornavirus-infected lines had faster seed germination, longer radicle, lower chlorophyll content, higher carotene content, longer pods, and higher weight of 100 seeds, all of which were statistically significant. The endornaviruses were not associated with visible pathogenic effects.

Non-Tuberculous Mycobacteria. An Emerging Threat?

PubMed

Martínez González, Susana; Cano Cortés, Arantxa; Sota Yoldi, Luis Alfonso; García García, José María; Alba Álvarez, Luz María; Palacios Gutiérrez, Juan José

2017-10-01

Non-tuberculous mycobacteria (NTM) isolates are becoming more common. The main objective of our study was to establish the number and diversity of NTM species in our region and their distribution according to the source sample, age and gender of the patients, and to analyse clinically significant isolates. Prospective study of all NTM isolated in Asturias from 2005 to 2012. Samples were processed following internationally accepted guidelines. Statistical analysis was based on Fisher's exact test for 2×2 contingency tables. A total of 3,284 mycobacteria were isolated: 1,499 Mycobacterium tuberculosis complex (MTB) and 1,785 NTM.During the study, NTM isolation rates increased while MTB isolation decreased. NTM were more frequent in men (P<.001). M.gordonae was the most frequently isolated species but did not cause disease in any case. NTM isolates from 212 patients were associated with clinically significant disease (17.1%). M.kansasii and M.avium were most commonly associated with disease. The number of M.kansasii isolates from men was statistically significant (P<.01). In our study, NTM isolates increased by 35%, compared with a 21% decline in cases of MTB. Both isolation of NTM and clinically significant cases were more common in men. Only 17.1% of NTM isolates were associated with disease, most commonly M.avium complex and M.kansasii. Copyright © 2017 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

A five year review of paediatric burns and social deprivation: Is there a link?

PubMed

Richards, Helen; Kokocinska, Maria; Lewis, Darren

2017-09-01

To establish if there is a correlation between burn incidence and social deprivation in order to formulate a more effective burns prevention strategy. A quantitative retrospective review of International Burn Injury Database (IBID) was carried out over a period from 2006 to 2011 to obtain data for children referred to our burns centre in West Midlands. Social deprivation scores for geographical areas were obtained from Office of National Statistics (ONS). Statistical analysis was carried out using Graphpad Prism. 1688 children were reviewed at our burns centre. Statistical analysis using Pearson correlation coefficient showed a slight association between social deprivation and increasing burn incidence r 2 =0.1268, 95% confidence interval 0.018-0.219, p value<0.0001. There was a slight male preponderance (58%). The most common mechanism of injury was scalding (61%). The most commonly affected age group were 1-2 year olds (38%). There were statistically significant differences in the ethnicity of children with significantly more children from Asian and African backgrounds being referred compared to Caucasian children. We found that appropriate first aid was administered in 67% of cases overall. We did not find a statistically significant link between first aid provision and social deprivation score. There was only a slight positive correlation between social deprivation and burn incidence. However, there did not seem to be any change in mechanism of burn in the most deprived groups compared to overall pattern, nor was there a significant difference in appropriate first aid provision. It would seem that dissemination of burn prevention strategies and first aid advice need to be improved across all geographical areas as this was uniformly lacking and the increased burn incidence in more socially deprived groups, although present, was not statistically significant. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Common variants of the EPDR1 gene and the risk of Dupuytren’s disease.

PubMed

Dębniak, T; Żyluk, A; Puchalski, P; Serrano-Fernandez, P

2013-10-01

The object of this study was the investigation of 3 common variants of single nucleotide polymorphisms of the ependymin-related gene 1 and its association with the occurrence of Dupuytren's disease. DNA samples were obtained from the peripheral blood of 508 consecutive patients. The control group comprised 515 healthy adults who were age-matched with the Dupuytren's patients. 3 common variants were analysed using TaqMan® genotyping assays and sequencing. The differences in the frequencies of variants of single nucleotide polymorphisms in patients and the control group were statistically tested. Additionally, haplotype frequency and linkage disequilibrium were analysed for these variants. A statistically significant association was noted between rs16879765_CT, rs16879765_TT and rs13240429_AA variants and Dupuytren's disease. 2 haplotypes: rs2722280_C+rs13240429_A+rs16879765_C and rs2722280_C+rs13240429_G+rs16879765_T were found to be statistically significantly associated with Dupuytren's disease. Moreover, we found that rs13240429 and rs16879765 variants were in strong linkage disequilibrium, while rs2722280 was only in moderate linkage disequilibrium. No significant differences were found in the frequencies of the variants of the gene between the groups with a positive and negative familial history of Dupuytren's disease. In conclusion, results of this study suggest that EPDR1 gene can be added to a growing list of genes associated with Dupuytren's disease development. © Georg Thieme Verlag KG Stuttgart · New York.

Substantial increase in concurrent droughts and heatwaves in the United States

PubMed Central

Mazdiyasni, Omid; AghaKouchak, Amir

2015-01-01

A combination of climate events (e.g., low precipitation and high temperatures) may cause a significant impact on the ecosystem and society, although individual events involved may not be severe extremes themselves. Analyzing historical changes in concurrent climate extremes is critical to preparing for and mitigating the negative effects of climatic change and variability. This study focuses on the changes in concurrences of heatwaves and meteorological droughts from 1960 to 2010. Despite an apparent hiatus in rising temperature and no significant trend in droughts, we show a substantial increase in concurrent droughts and heatwaves across most parts of the United States, and a statistically significant shift in the distribution of concurrent extremes. Although commonly used trend analysis methods do not show any trend in concurrent droughts and heatwaves, a unique statistical approach discussed in this study exhibits a statistically significant change in the distribution of the data. PMID:26324927

Substantial increase in concurrent droughts and heatwaves in the United States.

PubMed

Mazdiyasni, Omid; AghaKouchak, Amir

2015-09-15

A combination of climate events (e.g., low precipitation and high temperatures) may cause a significant impact on the ecosystem and society, although individual events involved may not be severe extremes themselves. Analyzing historical changes in concurrent climate extremes is critical to preparing for and mitigating the negative effects of climatic change and variability. This study focuses on the changes in concurrences of heatwaves and meteorological droughts from 1960 to 2010. Despite an apparent hiatus in rising temperature and no significant trend in droughts, we show a substantial increase in concurrent droughts and heatwaves across most parts of the United States, and a statistically significant shift in the distribution of concurrent extremes. Although commonly used trend analysis methods do not show any trend in concurrent droughts and heatwaves, a unique statistical approach discussed in this study exhibits a statistically significant change in the distribution of the data.

Genetics Home Reference: polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy

MedlinePlus

... feelings of intense happiness (euphoria), a loss of inhibition, and poor concentration. These neurologic changes cause significant ... Information What information about a genetic condition can statistics provide? Why are some genetic conditions more common ...

47 CFR 54.807 - Interstate access universal service support.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Common Carrier Bureau Report, Statistics of Communications Common Carriers, Table 6.10—Selected Operating Statistics. Interested parties may obtain this report from the U.S. Government Printing Office or by... Bureau Report, Statistics of Communications Common Carriers, Table 6.10—Selected Operating Statistics...

Consequences of common data analysis inaccuracies in CNS trauma injury basic research.

PubMed

Burke, Darlene A; Whittemore, Scott R; Magnuson, David S K

2013-05-15

The development of successful treatments for humans after traumatic brain or spinal cord injuries (TBI and SCI, respectively) requires animal research. This effort can be hampered when promising experimental results cannot be replicated because of incorrect data analysis procedures. To identify and hopefully avoid these errors in future studies, the articles in seven journals with the highest number of basic science central nervous system TBI and SCI animal research studies published in 2010 (N=125 articles) were reviewed for their data analysis procedures. After identifying the most common statistical errors, the implications of those findings were demonstrated by reanalyzing previously published data from our laboratories using the identified inappropriate statistical procedures, then comparing the two sets of results. Overall, 70% of the articles contained at least one type of inappropriate statistical procedure. The highest percentage involved incorrect post hoc t-tests (56.4%), followed by inappropriate parametric statistics (analysis of variance and t-test; 37.6%). Repeated Measures analysis was inappropriately missing in 52.0% of all articles and, among those with behavioral assessments, 58% were analyzed incorrectly. Reanalysis of our published data using the most common inappropriate statistical procedures resulted in a 14.1% average increase in significant effects compared to the original results. Specifically, an increase of 15.5% occurred with Independent t-tests and 11.1% after incorrect post hoc t-tests. Utilizing proper statistical procedures can allow more-definitive conclusions, facilitate replicability of research results, and enable more accurate translation of those results to the clinic.

Functional annotation of regulatory pathways.

PubMed

Pandey, Jayesh; Koyutürk, Mehmet; Kim, Yohan; Szpankowski, Wojciech; Subramaniam, Shankar; Grama, Ananth

2007-07-01

Standardized annotations of biomolecules in interaction networks (e.g. Gene Ontology) provide comprehensive understanding of the function of individual molecules. Extending such annotations to pathways is a critical component of functional characterization of cellular signaling at the systems level. We propose a framework for projecting gene regulatory networks onto the space of functional attributes using multigraph models, with the objective of deriving statistically significant pathway annotations. We first demonstrate that annotations of pairwise interactions do not generalize to indirect relationships between processes. Motivated by this result, we formalize the problem of identifying statistically overrepresented pathways of functional attributes. We establish the hardness of this problem by demonstrating the non-monotonicity of common statistical significance measures. We propose a statistical model that emphasizes the modularity of a pathway, evaluating its significance based on the coupling of its building blocks. We complement the statistical model by an efficient algorithm and software, Narada, for computing significant pathways in large regulatory networks. Comprehensive results from our methods applied to the Escherichia coli transcription network demonstrate that our approach is effective in identifying known, as well as novel biological pathway annotations. Narada is implemented in Java and is available at http://www.cs.purdue.edu/homes/jpandey/narada/.

Multifactor-Dimensionality Reduction Reveals High-Order Interactions among Estrogen-Metabolism Genes in Sporadic Breast Cancer

PubMed Central

Ritchie, Marylyn D.; Hahn, Lance W.; Roodi, Nady; Bailey, L. Renee; Dupont, William D.; Parl, Fritz F.; Moore, Jason H.

2001-01-01

One of the greatest challenges facing human geneticists is the identification and characterization of susceptibility genes for common complex multifactorial human diseases. This challenge is partly due to the limitations of parametric-statistical methods for detection of gene effects that are dependent solely or partially on interactions with other genes and with environmental exposures. We introduce multifactor-dimensionality reduction (MDR) as a method for reducing the dimensionality of multilocus information, to improve the identification of polymorphism combinations associated with disease risk. The MDR method is nonparametric (i.e., no hypothesis about the value of a statistical parameter is made), is model-free (i.e., it assumes no particular inheritance model), and is directly applicable to case-control and discordant-sib-pair studies. Using simulated case-control data, we demonstrate that MDR has reasonable power to identify interactions among two or more loci in relatively small samples. When it was applied to a sporadic breast cancer case-control data set, in the absence of any statistically significant independent main effects, MDR identified a statistically significant high-order interaction among four polymorphisms from three different estrogen-metabolism genes. To our knowledge, this is the first report of a four-locus interaction associated with a common complex multifactorial disease. PMID:11404819

Visualization of Differences in Data Measuring Mathematical Skills

ERIC Educational Resources Information Center

Zoubek, Lukas; Burda, Michal

2009-01-01

Identification of significant differences in sets of data is a common task of data mining. This paper describes a novel visualization technique that allows the user to interactively explore and analyze differences in mean values of analyzed attributes. Statistical tests of hypotheses are used to identify the significant differences and the results…

Applications of spatial statistical network models to stream data

USGS Publications Warehouse

Isaak, Daniel J.; Peterson, Erin E.; Ver Hoef, Jay M.; Wenger, Seth J.; Falke, Jeffrey A.; Torgersen, Christian E.; Sowder, Colin; Steel, E. Ashley; Fortin, Marie-Josée; Jordan, Chris E.; Ruesch, Aaron S.; Som, Nicholas; Monestiez, Pascal

2014-01-01

Streams and rivers host a significant portion of Earth's biodiversity and provide important ecosystem services for human populations. Accurate information regarding the status and trends of stream resources is vital for their effective conservation and management. Most statistical techniques applied to data measured on stream networks were developed for terrestrial applications and are not optimized for streams. A new class of spatial statistical model, based on valid covariance structures for stream networks, can be used with many common types of stream data (e.g., water quality attributes, habitat conditions, biological surveys) through application of appropriate distributions (e.g., Gaussian, binomial, Poisson). The spatial statistical network models account for spatial autocorrelation (i.e., nonindependence) among measurements, which allows their application to databases with clustered measurement locations. Large amounts of stream data exist in many areas where spatial statistical analyses could be used to develop novel insights, improve predictions at unsampled sites, and aid in the design of efficient monitoring strategies at relatively low cost. We review the topic of spatial autocorrelation and its effects on statistical inference, demonstrate the use of spatial statistics with stream datasets relevant to common research and management questions, and discuss additional applications and development potential for spatial statistics on stream networks. Free software for implementing the spatial statistical network models has been developed that enables custom applications with many stream databases.

The slip resistance of common footwear materials measured with two slipmeters.

PubMed

Chang, W R; Matz, S

2001-12-01

The slip resistance of 16 commonly used footwear materials was measured with the Brungraber Mark II and the English XL on 3 floor surfaces under surface conditions of dry, wet, oily and oily wet. Three samples were used for each material combination and surface condition. The results of a one way ANOVA analysis indicated that the differences among different samples were statistically significant for a large number of material combinations and surface conditions. The results indicated that the ranking of materials based on their slip resistance values depends highly on the slipmeters, floor surfaces and surface conditions. For contaminated surfaces including wet, oily and oily wet surfaces, the slip resistance obtained with the English XL was usually higher than that measured with the Brungraber Mark II. The correlation coefficients between the slip resistance obtained with these two slipmeters calculated for different surface conditions indicated a strong correlation with statistical significance.

Low statistical power in biomedical science: a review of three human research domains.

PubMed

Dumas-Mallet, Estelle; Button, Katherine S; Boraud, Thomas; Gonon, Francois; Munafò, Marcus R

2017-02-01

Studies with low statistical power increase the likelihood that a statistically significant finding represents a false positive result. We conducted a review of meta-analyses of studies investigating the association of biological, environmental or cognitive parameters with neurological, psychiatric and somatic diseases, excluding treatment studies, in order to estimate the average statistical power across these domains. Taking the effect size indicated by a meta-analysis as the best estimate of the likely true effect size, and assuming a threshold for declaring statistical significance of 5%, we found that approximately 50% of studies have statistical power in the 0-10% or 11-20% range, well below the minimum of 80% that is often considered conventional. Studies with low statistical power appear to be common in the biomedical sciences, at least in the specific subject areas captured by our search strategy. However, we also observe evidence that this depends in part on research methodology, with candidate gene studies showing very low average power and studies using cognitive/behavioural measures showing high average power. This warrants further investigation.

Low statistical power in biomedical science: a review of three human research domains

PubMed Central

Dumas-Mallet, Estelle; Button, Katherine S.; Boraud, Thomas; Gonon, Francois

2017-01-01

Studies with low statistical power increase the likelihood that a statistically significant finding represents a false positive result. We conducted a review of meta-analyses of studies investigating the association of biological, environmental or cognitive parameters with neurological, psychiatric and somatic diseases, excluding treatment studies, in order to estimate the average statistical power across these domains. Taking the effect size indicated by a meta-analysis as the best estimate of the likely true effect size, and assuming a threshold for declaring statistical significance of 5%, we found that approximately 50% of studies have statistical power in the 0–10% or 11–20% range, well below the minimum of 80% that is often considered conventional. Studies with low statistical power appear to be common in the biomedical sciences, at least in the specific subject areas captured by our search strategy. However, we also observe evidence that this depends in part on research methodology, with candidate gene studies showing very low average power and studies using cognitive/behavioural measures showing high average power. This warrants further investigation. PMID:28386409

An Independent Filter for Gene Set Testing Based on Spectral Enrichment.

PubMed

Frost, H Robert; Li, Zhigang; Asselbergs, Folkert W; Moore, Jason H

2015-01-01

Gene set testing has become an indispensable tool for the analysis of high-dimensional genomic data. An important motivation for testing gene sets, rather than individual genomic variables, is to improve statistical power by reducing the number of tested hypotheses. Given the dramatic growth in common gene set collections, however, testing is often performed with nearly as many gene sets as underlying genomic variables. To address the challenge to statistical power posed by large gene set collections, we have developed spectral gene set filtering (SGSF), a novel technique for independent filtering of gene set collections prior to gene set testing. The SGSF method uses as a filter statistic the p-value measuring the statistical significance of the association between each gene set and the sample principal components (PCs), taking into account the significance of the associated eigenvalues. Because this filter statistic is independent of standard gene set test statistics under the null hypothesis but dependent under the alternative, the proportion of enriched gene sets is increased without impacting the type I error rate. As shown using simulated and real gene expression data, the SGSF algorithm accurately filters gene sets unrelated to the experimental outcome resulting in significantly increased gene set testing power.

Statistics of contractive cracking patterns. [frozen soil-water rheology

NASA Technical Reports Server (NTRS)

Noever, David A.

1991-01-01

The statistics of convective soil patterns are analyzed using statistical crystallography. An underlying hierarchy of order is found to span four orders of magnitude in characteristic pattern length. Strict mathematical requirements determine the two-dimensional (2D) topology, such that random partitioning of space yields a predictable statistical geometry for polygons. For all lengths, Aboav's and Lewis's laws are verified; this result is consistent both with the need to fill 2D space and most significantly with energy carried not by the patterns' interior, but by the boundaries. Together, this suggests a common mechanism of formation for both micro- and macro-freezing patterns.

Testing for significance of phase synchronisation dynamics in the EEG.

PubMed

Daly, Ian; Sweeney-Reed, Catherine M; Nasuto, Slawomir J

2013-06-01

A number of tests exist to check for statistical significance of phase synchronisation within the Electroencephalogram (EEG); however, the majority suffer from a lack of generality and applicability. They may also fail to account for temporal dynamics in the phase synchronisation, regarding synchronisation as a constant state instead of a dynamical process. Therefore, a novel test is developed for identifying the statistical significance of phase synchronisation based upon a combination of work characterising temporal dynamics of multivariate time-series and Markov modelling. We show how this method is better able to assess the significance of phase synchronisation than a range of commonly used significance tests. We also show how the method may be applied to identify and classify significantly different phase synchronisation dynamics in both univariate and multivariate datasets.

Migration and common mental disorder: an improvement in mental health over time?

PubMed

Butler, Margaret; Warfa, Nasir; Khatib, Yasmin; Bhui, Kamaldeep

2015-02-01

Global migration is reaching record high levels and UK migrant groups comprise an increasing proportion of the total population. The migratory process causes stress that can affect mental health. There is limited consistent empirical evidence of a longitudinal nature to explain the association between migration and mental health. This review aims to examine the evidence of a relationship between migration and common mental disorder (CMD) amongst migrants over time. A comprehensive search of medical and psychiatric databases for global quantitative empirical studies investigating incidence of CMD amongst adult migrants from 1975 to July 2012 was conducted. Declines in rates of CMD amongst migrants over time were reported by two thirds of the 18 studies reviewed, less than one third of which were statistically significant. On the contrary, three studies showed an increased rate of CMD, one statistically significant. Individual psychological resources, social support, the acculturation process, cultural variations and time since relocation are identified as statistically significant protective factors against the development of CMD amongst migrants. New enlightening points include the significant impact of varying patterns of psychological distress, of which negative is the most adverse for CMD. Migration is an extremely complex process. Further clarification is needed to gain deeper understanding of the relationship between migration and CMD to address contradictions in the literature and health inequalities amongst migrants.

Circadian rhythm disruption was observed in hand, foot, and mouth disease patients.

PubMed

Zhu, Yu; Jiang, Zhou; Xiao, Guoguang; Cheng, Suting; Wen, Yang; Wan, Chaomin

2015-03-01

Hand, foot, and mouth disease (HFMD) with central nerve system complications may rapidly progress to fulminated cardiorespiratory failure, with higher mortality and worse prognosis. It has been reported that circadian rhythms of heart rate (HR) and respiratory rate are useful in predicting prognosis of severe cardiovascular and neurological diseases. The present study aims to investigate the characteristics of the circadian rhythms of HR, respiratory rate, and temperature in HFMD patients with neurological complications. Hospitalized HFMD patients including 33 common cases (common group), 61 severe cases (severe group), and 9 critical cases (critical group) were contrasted retrospectively. Their HR, respiratory rate, and temperatures were measured every 4 hours during the first 48-hour in the hospital. Data were analyzed with the least-squares fit of a 24-hour cosine function by the single cosinor and population-mean cosinor method. Results of population-mean cosinor analysis demonstrated that the circadian rhythm of HR, respiratory rate, and temperature was present in the common and severe group, but absent in the critical group. The midline-estimating statistic of rhythm (MESOR) (P = 0.016) and acrophase (P < 0.01) of temperature and respiratory rate were significantly different among 3 groups. But no statistical difference of amplitude in temperature and respiratory rate was observed among the 3 groups (P = 0.14). MESOR value of HR (P < 0.001) was significantly different in 3 groups. However, amplitude and acrophase revealed no statistical difference in circadian characteristics of HR among 3 groups. Compared with the common group, the MESOR of temperature and respiratory rate was significantly higher, and acrophase of temperature and respiratory rate was 2 hours ahead in the severe group, critical HFMD patients lost their population-circadian rhythm of temperature, HR, and respiratory rate. The high values of temperature and respiratory rate for the common group were concentrated between 3 and 9 PM, whereas those for the severe group were more dispersive. And the high values for the critical group were equally distributed in 24 hours of the day. Circadian rhythm of patients' temperature in the common group was the same as the normal rhythm of human body temperature. Circadian rhythm of patients' temperature, HR and respiratory rate in 3 groups were significantly different.

A comparison of risk factors associated with suicide ideation/attempts in American Indian and White youth in Montana.

PubMed

Manzo, Karen; Tiesman, Hope; Stewart, Jera; Hobbs, Gerald R; Knox, Sarah S

2015-01-01

We examined racial/ethnic and gender-specific associations between suicide ideation/attempts and risky behaviors, sadness/hopelessness, and victimization in Montana American Indian and White youth using 1999-2011 Youth Risk Behavior Survey data. Logistic regression was used to calculate odds ratios and 95% confidence intervals in stratified racial/ethnic-gender groups. The primary results of this study show that although the American Indian youth had more statistically significant suicidal thoughts and attempts than the White youth, they had fewer statistically significant predictors compared to the White youth. Sadness/hopelessness was the strongest, and the only statistically significant, predictor of suicide ideation/attempts common across all four groups. The unhealthy weight control cluster was a significant predictor for the White youth and the American Indian/Alaska Native girls; the alcohol/tobacco/marijuana cluster was a significant predictor for the American Indian boys only. Results show important differences across the groups and indicate directions for future research targeting prevention and intervention.

The other half of the story: effect size analysis in quantitative research.

PubMed

Maher, Jessica Middlemis; Markey, Jonathan C; Ebert-May, Diane

2013-01-01

Statistical significance testing is the cornerstone of quantitative research, but studies that fail to report measures of effect size are potentially missing a robust part of the analysis. We provide a rationale for why effect size measures should be included in quantitative discipline-based education research. Examples from both biological and educational research demonstrate the utility of effect size for evaluating practical significance. We also provide details about some effect size indices that are paired with common statistical significance tests used in educational research and offer general suggestions for interpreting effect size measures. Finally, we discuss some inherent limitations of effect size measures and provide further recommendations about reporting confidence intervals.

A common base method for analysis of qPCR data and the application of simple blocking in qPCR experiments.

PubMed

Ganger, Michael T; Dietz, Geoffrey D; Ewing, Sarah J

2017-12-01

qPCR has established itself as the technique of choice for the quantification of gene expression. Procedures for conducting qPCR have received significant attention; however, more rigorous approaches to the statistical analysis of qPCR data are needed. Here we develop a mathematical model, termed the Common Base Method, for analysis of qPCR data based on threshold cycle values (C q ) and efficiencies of reactions (E). The Common Base Method keeps all calculations in the logscale as long as possible by working with log 10 (E) ∙ C q , which we call the efficiency-weighted C q value; subsequent statistical analyses are then applied in the logscale. We show how efficiency-weighted C q values may be analyzed using a simple paired or unpaired experimental design and develop blocking methods to help reduce unexplained variation. The Common Base Method has several advantages. It allows for the incorporation of well-specific efficiencies and multiple reference genes. The method does not necessitate the pairing of samples that must be performed using traditional analysis methods in order to calculate relative expression ratios. Our method is also simple enough to be implemented in any spreadsheet or statistical software without additional scripts or proprietary components.

Reporting Practices and Use of Quantitative Methods in Canadian Journal Articles in Psychology.

PubMed

Counsell, Alyssa; Harlow, Lisa L

2017-05-01

With recent focus on the state of research in psychology, it is essential to assess the nature of the statistical methods and analyses used and reported by psychological researchers. To that end, we investigated the prevalence of different statistical procedures and the nature of statistical reporting practices in recent articles from the four major Canadian psychology journals. The majority of authors evaluated their research hypotheses through the use of analysis of variance (ANOVA), t -tests, and multiple regression. Multivariate approaches were less common. Null hypothesis significance testing remains a popular strategy, but the majority of authors reported a standardized or unstandardized effect size measure alongside their significance test results. Confidence intervals on effect sizes were infrequently employed. Many authors provided minimal details about their statistical analyses and less than a third of the articles presented on data complications such as missing data and violations of statistical assumptions. Strengths of and areas needing improvement for reporting quantitative results are highlighted. The paper concludes with recommendations for how researchers and reviewers can improve comprehension and transparency in statistical reporting.

What's in a Name?

NASA Astrophysics Data System (ADS)

Bonneau, Joseph; Just, Mike; Matthews, Greg

We study the efficiency of statistical attacks on human authentication systems relying on personal knowledge questions. We adapt techniques from guessing theory to measure security against a trawling attacker attempting to compromise a large number of strangers' accounts. We then examine a diverse corpus of real-world statistical distributions for likely answer categories such as the names of people, pets, and places and find that personal knowledge questions are significantly less secure than graphical or textual passwords. We also demonstrate that statistics can be used to increase security by proactively shaping the answer distribution to lower the prevalence of common responses.

[How to start a neuroimaging study].

PubMed

Narumoto, Jin

2012-06-01

In order to help researchers understand how to start a neuroimaging study, several tips are described in this paper. These include 1) Choice of an imaging modality, 2) Statistical method, and 3) Interpretation of the results. 1) There are several imaging modalities available in clinical research. Advantages and disadvantages of each modality are described. 2) Statistical Parametric Mapping, which is the most common statistical software for neuroimaging analysis, is described in terms of parameter setting in normalization and level of significance. 3) In the discussion section, the region which shows a significant difference between patients and normal controls should be discussed in relation to the neurophysiology of the disease, making reference to previous reports from neuroimaging studies in normal controls, lesion studies and animal studies. A typical pattern of discussion is described.

Adolescent cigarette smoking and health risk behavior.

PubMed

Busen, N H; Modeland, V; Kouzekanani, K

2001-06-01

During the past 30 years, tobacco use among adolescents has substantially increased, resulting in major health problems associated with tobacco consumption. The purpose of this study was to identify adolescent smoking behaviors and to determine the relationship among smoking, specific demographic variables, and health risk behaviors. The sample consisted of 93 self-selecting adolescents. An ex post facto design was used for this study and data were analyzed by using nonparametric statistics. Findings included a statistically significant relationship between lifetime cigarette use and ethnicity. Statistically significant relationships were also found among current cigarette use and ethnicity, alcohol use, marijuana use, suicidal thoughts, and age at first sexual intercourse. Nurses and other providers must recognize that cigarette smoking may indicate other risk behaviors common among adolescents. Copyright 2001 by W.B. Saunders Company

Assessment of the efficacy and safety profiles of aspirin and acetaminophen with codeine: results from 2 randomized, controlled trials in individuals with tension-type headache and postoperative dental pain.

PubMed

Gatoulis, Sergio C; Voelker, Michael; Fisher, Matt

2012-01-01

Aspirin is a widely used NSAID that has been extensively studied in numerous conditions. Nonprescription analgesics, such as aspirin, are frequently used for a wide variety of common ailments, including conditions such as dental pain and tension-type headache. We sought to compare the efficacy and safety profiles of aspirin, acetaminophen with codeine, and placebo in the treatment of post-operative dental pain and tension-type headache. These were 2 randomized, double-blind, placebo-controlled, single-dose clinical trials that assigned participants (2:2:1) to receive either aspirin (1000 mg), acetaminophen (300 mg) with codeine (30 mg), or placebo. The primary efficacy end point was the sum of pain intensity differences from baseline (SPID) over 6 hours for the dental pain study and over 4 hours for the tension-type headache study. Other common analgesic measures, in addition to safety, were also evaluated. The results of the dental pain study for aspirin and acetaminophen with codeine suggest statistically significant efficacy for all measures compared with placebo at all time points. Aspirin provided statistically significant efficacy compared with acetaminophen with codeine for SPID(0-4) (P = 0.028). In the tension-type headache study, aspirin and acetaminophen with codeine provided statistically significant efficacy compared with placebo for SPID(0-4) and SPID(0-6) (P < 0.001) and for total pain relief (P < 0.001). There were no significant differences between aspirin and acetaminophen with codeine at any evaluation of SPID (P ≥ 0.070), complete relief (P ≥ 0.179), or time to meaningful relief (P ≥ 0.245). Regarding safety, there were no statistically significant differences between treatment groups in the incidence of adverse events in the dental pain and tension-type headache studies. These 2 randomized, double-blind, placebo-controlled studies demonstrate that treatment with aspirin (1000 mg) provides statistically significant analgesic efficacy compared with placebo use and comparable efficacy with acetaminophen (300 mg) with codeine (30 mg) therapy after impacted third molar extraction and in tension- type headache. Copyright © 2012 Elsevier HS Journals, Inc. All rights reserved.

Finding differentially expressed genes in high dimensional data: Rank based test statistic via a distance measure.

PubMed

Mathur, Sunil; Sadana, Ajit

2015-12-01

We present a rank-based test statistic for the identification of differentially expressed genes using a distance measure. The proposed test statistic is highly robust against extreme values and does not assume the distribution of parent population. Simulation studies show that the proposed test is more powerful than some of the commonly used methods, such as paired t-test, Wilcoxon signed rank test, and significance analysis of microarray (SAM) under certain non-normal distributions. The asymptotic distribution of the test statistic, and the p-value function are discussed. The application of proposed method is shown using a real-life data set. © The Author(s) 2011.

Testing statistical isotropy in cosmic microwave background polarization maps

NASA Astrophysics Data System (ADS)

Rath, Pranati K.; Samal, Pramoda Kumar; Panda, Srikanta; Mishra, Debesh D.; Aluri, Pavan K.

2018-04-01

We apply our symmetry based Power tensor technique to test conformity of PLANCK Polarization maps with statistical isotropy. On a wide range of angular scales (l = 40 - 150), our preliminary analysis detects many statistically anisotropic multipoles in foreground cleaned full sky PLANCK polarization maps viz., COMMANDER and NILC. We also study the effect of residual foregrounds that may still be present in the Galactic plane using both common UPB77 polarization mask, as well as the individual component separation method specific polarization masks. However, some of the statistically anisotropic modes still persist, albeit significantly in NILC map. We further probed the data for any coherent alignments across multipoles in several bins from the chosen multipole range.

The impact of female genital cutting on health of newly married women.

PubMed

Elnashar, A; Abdelhady, R

2007-06-01

To detect the rate of female genital cutting among a sample of newly married women in Benha city, and make a comparison between circumcised and non-circumcised women regarding long-term health problems. Randomly selected (264) newly married women were the subjects of this work. Circumcised group constitutes 75.8% of the sample. All non-circumcised women were living in an urban area. Dysmenorrhea was more common among circumcised rather than non-circumcised, with statistically significant difference (P<0.01). Marital problems (dyspareunia, loss of libido, failure of orgasm and husband's dissatisfaction) had statistically different levels of significance among circumcised women. Obstetric problems such as tears, episiotomy and consequently distressed babies were more events among circumcised mothers with statistical significance. Circumcised females had significant mental problems such as somatization, anxiety and phobia (P<0.001). Female genital cutting remains a widely practiced custom in our society. Grave complications of circumcision may last throughout women's life particularly the time of consummation of marriage and the time of childbirth.

THE NEUROLOGICAL FACE OF CELIAC DISEASE.

PubMed

Işikay, Sedat; Kocamaz, Halil

2015-01-01

Several neurological disorders have also been widely described in celiac disease patients. The aim of this study was to determine the incidence of accompanying different neurologic manifestations in children with celiac disease at the time of diagnosis and to discuss these manifestations in the light of the recent literature. This prospective cross sectional study included 297 children diagnosed with celiac disease. The medical records of all patients were reviewed. In neurological evaluation, totally 40 (13. 5%) of the 297 celiac patients had a neurological finding including headache, epilepsy, migraine, mental retardation, breath holding spells, ataxia, cerebral palsy, attention deficit hyperactivity disorder, Down syndrome and Turner syndrome in order of frequency. There was not any significant difference between the laboratory data of the patients with and without neurological manifestations. However; type 3a biopsy was statistically significantly more common among patients without neurological manifestations, while type 3b biopsy was statistically significantly more common among patients with neurological manifestations. It is important to keep in mind that in clinical course of celiac disease different neurological manifestations may be reported.

Anatomical variations of uncinate process observed in chronic sinusitis.

PubMed

Tuli, Isha Preet; Sengupta, Subhabrata; Munjal, Sudeep; Kesari, Santosh Prasad; Chakraborty, Suvamoy

2013-04-01

Chronic Sinusitis, an extremely persistent illness, is surgically best treated by Functional Endoscopic Sinus Surgery. The ostiomeatal complex is the main area targeted and within it uncinate process is the first anatomical structure encountered. The significance of anatomical variations concerning age and sex of uncinate process in chronic sinusitis were evaluated. A prospective study on 50 patients of chronic sinusitis (100 uncinate processes) was done. The results were tabulated and analyzed using Statistical Package for Social Science (SPSS) 16.0. Type I superior attachment of uncinate process (67 %) was the most common variety in all ages and both sexes and a statistically significant relationship between Type I superior attachment of uncinate process and sex was found (p < 0.05). The typical uncinate process was most common (70 %) followed by medial deviation of the uncinate (24 %). This difference in occurrence was significant with respect to both age and sex (p < 0.05). Anatomical variations of uncinate process are not responsible for causing chronic sinusitis. Mere presence of these variations of uncinate is not an indication for FESS.

A local basal area adjustment for crown width prediction

Treesearch

Don C. Bragg

2001-01-01

Nonlinear crown width regressive equations were developed for 24 species common to the upper Lake States of Michigan, Minnesota, and Wisconsin. Of the species surveyed, 15 produced statistically significant (P 0.05) local basal area effect coefficients showing a reduction in crown...

Impact of Injury Mechanisms on Patterns and Management of Facial Fractures.

PubMed

Greathouse, S Travis; Adkinson, Joshua M; Garza, Ramon; Gilstrap, Jarom; Miller, Nathan F; Eid, Sherrine M; Murphy, Robert X

2015-07-01

Mechanisms causing facial fractures have evolved over time and may be predictive of the types of injuries sustained. The objective of this study is to examine the impact of mechanisms of injury on the type and management of facial fractures at our Level 1 Trauma Center. The authors performed an Institutional Review Board-approved review of our network's trauma registry from 2006 to 2010, documenting age, sex, mechanism, Injury Severity Score, Glasgow Coma Scale, facial fracture patterns (nasal, maxillary/malar, orbital, mandible), and reconstructions. Mechanism rates were compared using a Pearson χ2 test. The database identified 23,318 patients, including 1686 patients with facial fractures and a subset of 1505 patients sustaining 2094 fractures by motor vehicle collision (MVC), fall, or assault. Nasal fractures were the most common injuries sustained by all mechanisms. MVCs were most likely to cause nasal and malar/maxillary fractures (P < 0.01). Falls were the least likely and assaults the most likely to cause mandible fractures (P < 0.001), the most common injury leading to surgical intervention (P < 0.001). Although not statistically significant, fractures sustained in MVCs were the most likely overall to undergo surgical intervention. Age, number of fractures, and alcohol level were statistically significant variables associated with operative management. Age and number of fractures sustained were associated with operative intervention. Although there is a statistically significant correlation between mechanism of injury and type of facial fracture sustained, none of the mechanisms evaluated herein are statistically associated with surgical intervention. Clinical Question/Level of Evidence: Therapeutic, III.

Anthropometric Study of the Piriformis Muscle and Sciatic Nerve: A Morphological Analysis in a Polish Population

PubMed Central

Haładaj, Robert; Pingot, Mariusz; Polguj, Michał; Wysiadecki, Grzegorz; Topol, Mirosław

2015-01-01

Background The aim of this study was to determine relationships between piriformis muscle (PM) and sciatic nerve (SN) with reference to sex and anatomical variations. Material/Methods Deep dissection of the gluteal region was performed on 30 randomized, formalin-fixed human lower limbs of adults of both sexes of the Polish population. Anthropometric measurements were taken and then statistically analyzed. Results The conducted research revealed that, apart from the typical structure of the piriformis muscle, the most common variation was division of the piriformis muscle into two heads, with the common peroneal nerve running between them (20%). The group with anatomical variations of the sciatic nerve course displayed greater diversity of morphometric measurement results. There was a statistically significant correlation between the lower limb length and the distance from the sciatic nerve to the greater trochanter in the male specimens. On the other hand, in the female specimens, a statistically significant correlation was observed between the lower limb length and the distance from the sciatic nerve to the ischial tuberosity. The shortest distance from the sciatic nerve to the greater trochanter measured at the level of the inferior edge of the piriformis was 21 mm, while the shortest distance to the ischial tuberosity was 63 mm. Such correlations should be taken into account during invasive medical procedures performed in the gluteal region. Conclusions It is possible to distinguish several anatomical variations of the sciatic nerve course within the deep gluteal region. The statistically significant correlations between some anthropometric measurements were only present within particular groups of male and female limbs. PMID:26629744

The extent and consequences of p-hacking in science.

PubMed

Head, Megan L; Holman, Luke; Lanfear, Rob; Kahn, Andrew T; Jennions, Michael D

2015-03-01

A focus on novel, confirmatory, and statistically significant results leads to substantial bias in the scientific literature. One type of bias, known as "p-hacking," occurs when researchers collect or select data or statistical analyses until nonsignificant results become significant. Here, we use text-mining to demonstrate that p-hacking is widespread throughout science. We then illustrate how one can test for p-hacking when performing a meta-analysis and show that, while p-hacking is probably common, its effect seems to be weak relative to the real effect sizes being measured. This result suggests that p-hacking probably does not drastically alter scientific consensuses drawn from meta-analyses.

Sb2Te3 and Its Superlattices: Optimization by Statistical Design.

PubMed

Behera, Jitendra K; Zhou, Xilin; Ranjan, Alok; Simpson, Robert E

2018-05-02

The objective of this work is to demonstrate the usefulness of fractional factorial design for optimizing the crystal quality of chalcogenide van der Waals (vdW) crystals. We statistically analyze the growth parameters of highly c axis oriented Sb 2 Te 3 crystals and Sb 2 Te 3 -GeTe phase change vdW heterostructured superlattices. The statistical significance of the growth parameters of temperature, pressure, power, buffer materials, and buffer layer thickness was found by fractional factorial design and response surface analysis. Temperature, pressure, power, and their second-order interactions are the major factors that significantly influence the quality of the crystals. Additionally, using tungsten rather than molybdenum as a buffer layer significantly enhances the crystal quality. Fractional factorial design minimizes the number of experiments that are necessary to find the optimal growth conditions, resulting in an order of magnitude improvement in the crystal quality. We highlight that statistical design of experiment methods, which is more commonly used in product design, should be considered more broadly by those designing and optimizing materials.

Inconsistency between direct and indirect comparisons of competing interventions: meta-epidemiological study.

PubMed

Song, Fujian; Xiong, Tengbin; Parekh-Bhurke, Sheetal; Loke, Yoon K; Sutton, Alex J; Eastwood, Alison J; Holland, Richard; Chen, Yen-Fu; Glenny, Anne-Marie; Deeks, Jonathan J; Altman, Doug G

2011-08-16

To investigate the agreement between direct and indirect comparisons of competing healthcare interventions. Meta-epidemiological study based on sample of meta-analyses of randomised controlled trials. Data sources Cochrane Database of Systematic Reviews and PubMed. Inclusion criteria Systematic reviews that provided sufficient data for both direct comparison and independent indirect comparisons of two interventions on the basis of a common comparator and in which the odds ratio could be used as the outcome statistic. Inconsistency measured by the difference in the log odds ratio between the direct and indirect methods. The study included 112 independent trial networks (including 1552 trials with 478,775 patients in total) that allowed both direct and indirect comparison of two interventions. Indirect comparison had already been explicitly done in only 13 of the 85 Cochrane reviews included. The inconsistency between the direct and indirect comparison was statistically significant in 16 cases (14%, 95% confidence interval 9% to 22%). The statistically significant inconsistency was associated with fewer trials, subjectively assessed outcomes, and statistically significant effects of treatment in either direct or indirect comparisons. Owing to considerable inconsistency, many (14/39) of the statistically significant effects by direct comparison became non-significant when the direct and indirect estimates were combined. Significant inconsistency between direct and indirect comparisons may be more prevalent than previously observed. Direct and indirect estimates should be combined in mixed treatment comparisons only after adequate assessment of the consistency of the evidence.

Inconsistency between direct and indirect comparisons of competing interventions: meta-epidemiological study

PubMed Central

Xiong, Tengbin; Parekh-Bhurke, Sheetal; Loke, Yoon K; Sutton, Alex J; Eastwood, Alison J; Holland, Richard; Chen, Yen-Fu; Glenny, Anne-Marie; Deeks, Jonathan J; Altman, Doug G

2011-01-01

Objective To investigate the agreement between direct and indirect comparisons of competing healthcare interventions. Design Meta-epidemiological study based on sample of meta-analyses of randomised controlled trials. Data sources Cochrane Database of Systematic Reviews and PubMed. Inclusion criteria Systematic reviews that provided sufficient data for both direct comparison and independent indirect comparisons of two interventions on the basis of a common comparator and in which the odds ratio could be used as the outcome statistic. Main outcome measure Inconsistency measured by the difference in the log odds ratio between the direct and indirect methods. Results The study included 112 independent trial networks (including 1552 trials with 478 775 patients in total) that allowed both direct and indirect comparison of two interventions. Indirect comparison had already been explicitly done in only 13 of the 85 Cochrane reviews included. The inconsistency between the direct and indirect comparison was statistically significant in 16 cases (14%, 95% confidence interval 9% to 22%). The statistically significant inconsistency was associated with fewer trials, subjectively assessed outcomes, and statistically significant effects of treatment in either direct or indirect comparisons. Owing to considerable inconsistency, many (14/39) of the statistically significant effects by direct comparison became non-significant when the direct and indirect estimates were combined. Conclusions Significant inconsistency between direct and indirect comparisons may be more prevalent than previously observed. Direct and indirect estimates should be combined in mixed treatment comparisons only after adequate assessment of the consistency of the evidence. PMID:21846695

Statistical correlations of crime with arrests

NASA Astrophysics Data System (ADS)

Kuelling, Albert C.

1997-01-01

Regression analysis shows that the overall crime rate correlates with the overall arrest rate. Violent crime only weakly correlates with the violent arrest rate, but strongly correlates with the property arrest rate. Contrary to common impressions, increasing arrest rates do not significantly increase loading on incarceration facilities.

Comparison of Salmonella enteritidis phage types isolated from layers and humans in Belgium in 2005.

PubMed

Welby, Sarah; Imberechts, Hein; Riocreux, Flavien; Bertrand, Sophie; Dierick, Katelijne; Wildemauwe, Christa; Hooyberghs, Jozef; Van der Stede, Yves

2011-08-01

The aim of this study was to investigate the available results for Belgium of the European Union coordinated monitoring program (2004/665 EC) on Salmonella in layers in 2005, as well as the results of the monthly outbreak reports of Salmonella Enteritidis in humans in 2005 to identify a possible statistical significant trend in both populations. Separate descriptive statistics and univariate analysis were carried out and the parametric and/or non-parametric hypothesis tests were conducted. A time cluster analysis was performed for all Salmonella Enteritidis phage types (PTs) isolated. The proportions of each Salmonella Enteritidis PT in layers and in humans were compared and the monthly distribution of the most common PT, isolated in both populations, was evaluated. The time cluster analysis revealed significant clusters during the months May and June for layers and May, July, August, and September for humans. PT21, the most frequently isolated PT in both populations in 2005, seemed to be responsible of these significant clusters. PT4 was the second most frequently isolated PT. No significant difference was found for the monthly trend evolution of both PT in both populations based on parametric and non-parametric methods. A similar monthly trend of PT distribution in humans and layers during the year 2005 was observed. The time cluster analysis and the statistical significance testing confirmed these results. Moreover, the time cluster analysis showed significant clusters during the summer time and slightly delayed in time (humans after layers). These results suggest a common link between the prevalence of Salmonella Enteritidis in layers and the occurrence of the pathogen in humans. Phage typing was confirmed to be a useful tool for identifying temporal trends.

Prostate-Specific Antigen (PSA)–Based Population Screening for Prostate Cancer: An Evidence-Based Analysis

PubMed Central

Pron, G

2015-01-01

Background Prostate cancer (PC) is the most commonly diagnosed non-cutaneous cancer in men and their second or third leading cause of cancer death. Prostate-specific antigen (PSA) testing for PC has been in common practice for more than 20 years. Objectives A systematic review of the scientific literature was conducted to determine the effectiveness of PSA-based population screening programs for PC to inform policy decisions in a publicly funded health care system. Data Sources A systematic review of bibliographic databases was performed for systematic reviews or randomized controlled trials (RCT) of PSA-based population screening programs for PC. Review Methods A broad search strategy was employed to identify studies reporting on key outcomes of PC mortality and all-cause mortality. Results The search identified 5 systematic reviews and 6 RCTs. None of the systematic reviews found a statistically significant reduction in relative risk (RR) of PC mortality or overall mortality with PSA-based screening. PC mortality reductions were found to vary by country, by screening program, and by age of men at study entry. The European Randomized Study of Screening for Prostate Cancer found a statistically significant reduction in RR in PC mortality at 11-year follow-up (0.79; 95% CI, 0.67–0.92), although the absolute risk reduction was small (1.0/10,000 person-years). However, the primary treatment for PCs differed significantly between countries and between trial arms. The American Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) found a statistically non-significant increase in RR for PC mortality with 13-year follow-up (1.09; 95% CI, 0.87–1.36). The degree of opportunistic screening in the control arm of the PLCO trial, however, was high. None of the RCTs found a reduction in all-cause mortality and all found a statistically significant increase in the detection of mainly low-risk, organ-confined PCs in the screening arm. Conclusions There was no evidence of a PC mortality reduction in the American PLCO trial, which investigated a screening program in a setting where opportunistic screening was already common practice. Given that opportunistic PSA screening practices in Canada are similar, it is unlikely that the introduction of a formal PSA screening program would reduce PC mortality. PMID:26366236

Prostate-Specific Antigen (PSA)-Based Population Screening for Prostate Cancer: An Evidence-Based Analysis.

PubMed

Pron, G

2015-01-01

Prostate cancer (PC) is the most commonly diagnosed non-cutaneous cancer in men and their second or third leading cause of cancer death. Prostate-specific antigen (PSA) testing for PC has been in common practice for more than 20 years. A systematic review of the scientific literature was conducted to determine the effectiveness of PSA-based population screening programs for PC to inform policy decisions in a publicly funded health care system. A systematic review of bibliographic databases was performed for systematic reviews or randomized controlled trials (RCT) of PSA-based population screening programs for PC. A broad search strategy was employed to identify studies reporting on key outcomes of PC mortality and all-cause mortality. The search identified 5 systematic reviews and 6 RCTs. None of the systematic reviews found a statistically significant reduction in relative risk (RR) of PC mortality or overall mortality with PSA-based screening. PC mortality reductions were found to vary by country, by screening program, and by age of men at study entry. The European Randomized Study of Screening for Prostate Cancer found a statistically significant reduction in RR in PC mortality at 11-year follow-up (0.79; 95% CI, 0.67-0.92), although the absolute risk reduction was small (1.0/10,000 person-years). However, the primary treatment for PCs differed significantly between countries and between trial arms. The American Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) found a statistically non-significant increase in RR for PC mortality with 13-year follow-up (1.09; 95% CI, 0.87-1.36). The degree of opportunistic screening in the control arm of the PLCO trial, however, was high. None of the RCTs found a reduction in all-cause mortality and all found a statistically significant increase in the detection of mainly low-risk, organ-confined PCs in the screening arm. There was no evidence of a PC mortality reduction in the American PLCO trial, which investigated a screening program in a setting where opportunistic screening was already common practice. Given that opportunistic PSA screening practices in Canada are similar, it is unlikely that the introduction of a formal PSA screening program would reduce PC mortality.

Trend analysis of body weight parameters, mortality, and incidence of spontaneous tumors in Tg.rasH2 mice.

PubMed

Paranjpe, Madhav G; Denton, Melissa D; Vidmar, Tom; Elbekai, Reem H

2014-01-01

Carcinogenicity studies have been performed in conventional 2-year rodent studies for at least 3 decades, whereas the short-term carcinogenicity studies in transgenic mice, such as Tg.rasH2, have only been performed over the last decade. In the 2-year conventional rodent studies, interlinked problems, such as increasing trends in the initial body weights, increased body weight gains, high incidence of spontaneous tumors, and low survival, that complicate the interpretation of findings have been well established. However, these end points have not been evaluated in the short-term carcinogenicity studies involving the Tg.rasH2 mice. In this article, we present retrospective analysis of data obtained from control groups in 26-week carcinogenicity studies conducted in Tg.rasH2 mice since 2004. Our analysis showed statistically significant decreasing trends in initial body weights of both sexes. Although the terminal body weights did not show any significant trends, there was a statistically significant increasing trend toward body weight gains, more so in males than in females, which correlated with increasing trends in the food consumption. There were no statistically significant alterations in mortality trends. In addition, the incidence of all common spontaneous tumors remained fairly constant with no statistically significant differences in trends. © The Author(s) 2014.

Statistical process control in nursing research.

PubMed

Polit, Denise F; Chaboyer, Wendy

2012-02-01

In intervention studies in which randomization to groups is not possible, researchers typically use quasi-experimental designs. Time series designs are strong quasi-experimental designs but are seldom used, perhaps because of technical and analytic hurdles. Statistical process control (SPC) is an alternative analytic approach to testing hypotheses about intervention effects using data collected over time. SPC, like traditional statistical methods, is a tool for understanding variation and involves the construction of control charts that distinguish between normal, random fluctuations (common cause variation), and statistically significant special cause variation that can result from an innovation. The purpose of this article is to provide an overview of SPC and to illustrate its use in a study of a nursing practice improvement intervention. Copyright © 2011 Wiley Periodicals, Inc.

Evidence for prospective associations among depression and obesity in population-based studies.

PubMed

Faith, M S; Butryn, M; Wadden, T A; Fabricatore, A; Nguyen, A M; Heymsfield, S B

2011-05-01

Obesity may lead to depression or be one of its consequences. We reviewed population-based studies in order to, first, identify the most commonly used research methods, and, second, to evaluate the strength of evidence for prospective associations among obesity and depression. We examined 25 studies, of which 10 tested 'obesity-to-depression' pathways, and 15 tested 'depression-to-obesity' pathways. Descriptive statistics summarized the frequency with which various measurements, designs and data analytic strategies were used. We tallied the number of studies that reported any vs. no statistically significant associations, and report on effect sizes, identified moderating variables within reports, and sought common findings across studies. Results indicated considerable methodological heterogeneity in the literature. Depression was assessed by clinical interview in 44% of studies, weight and height were directly measured in 32%, and only 12% used both. In total, 80% of the studies reported significant obesity-to-depression associations, with odds ratios generally in the range of 1.0 to 2.0, while only 53% of the studies reported significant depression-to-obesity associations. Sex was a common moderating variable. Thus, there was good evidence that obesity is prospectively associated with increased depression, with less consistent evidence that depression leads to obesity. Recommendations for future research regarding study samples, measurement and data analysis are provided. © 2011 The Authors. obesity reviews © 2011 International Association for the Study of Obesity.

Development of polytoxicomania in function of defence from psychoticism.

PubMed

Nenadović, Milutin M; Sapić, Rosa

2011-01-01

Polytoxicomanic proportions in subpopulations of youth have been growing steadily in recent decades, and this trend is pan-continental. Psychoticism is a psychological construct that assumes special basic dimensions of personality disintegration and cognitive functions. Psychoticism may, in general, be the basis of pathological functioning of youth and influence the patterns of thought, feelings and actions that cause dysfunction. The aim of this study was to determine the distribution of basic dimensions of psychoticism for commitment of youth to abuse psychoactive substances (PAS) in order to reduce disturbing intrapsychic experiences or manifestation of psychotic symptoms. For the purpose of this study, two groups of respondents were formed, balanced by age, gender and family structure of origin (at least one parent alive). The study applied a DELTA-9 instrument for assessment of cognitive disintegration in function of establishing psychoticism and its operationalization. The obtained results were statistically analyzed. From the parameters of descriptive statistics, the arithmetic mean was calculated with measures of dispersion. A cross-tabular analysis of variables tested was performed, as well as statistical significance with Pearson's chi2-test, and analysis of variance. Age structure and gender are approximately represented in the group of polytoximaniacs and the control group. Testing did not confirm the statistically significant difference (p > 0.5). Statistical methodology established that they significantly differed in most variables of psychoticism, polytoxicomaniacs compared with a control group of respondents. Testing confirmed a high statistical significance of differences of variables of psychoticism in the group of respondents for p < 0.001 to p < 0.01. A statistically significant representation of the dimension of psychoticism in the polytoxicomaniac group was established. The presence of factors concerning common executive dysfunction was emphasized.

Analysis of pitching velocity in major league baseball players before and after ulnar collateral ligament reconstruction.

PubMed

Jiang, Jimmy J; Leland, J Martin

2014-04-01

Ulnar collateral ligament (UCL) reconstructions are relatively common among professional pitchers in Major League Baseball (MLB). To the authors' knowledge, there has not been a study specifically analyzing pitching velocity after UCL surgery. These measurements were examined in a cohort of MLB pitchers before and after UCL reconstruction. There is no significant loss in pitch velocity after UCL reconstruction in MLB pitchers. Cohort study; Level of evidence, 3. Between the years 2008 to 2010, a total of 41 MLB pitchers were identified as players who underwent UCL reconstruction. Inclusion criteria for this study consisted of a minimum of 1 year of preinjury and 2 years of postinjury pitch velocity data. After implementing exclusion criteria, performance data were analyzed from 28 of the 41 pitchers over a minimum of 4 MLB seasons for each player. A pair-matched control group of pitchers who did not have a known UCL injury were analyzed for comparison. Of the initial 41 players, 3 were excluded for revision UCL reconstruction. Eight of the 38 players who underwent primary UCL reconstruction did not return to pitching at the major league level, and 2 players who met the exclusion criteria were omitted, leaving data on 28 players available for final velocity analysis. The mean percentage change in the velocity of pitches thrown by players who underwent UCL reconstruction was not significantly different compared with that of players in the control group. The mean innings pitched was statistically different only for the year of injury and the first postinjury year. There were also no statistically significant differences between the 2 groups with regard to commonly used statistical performance measurements, including earned run average, batting average against, walks per 9 innings, strikeouts per 9 innings, and walks plus hits per inning pitched. There were no significant differences in pitch velocity and common performance measurements between players who returned to MLB after UCL reconstruction and pair-matched controls.

Applied statistics in ecology: common pitfalls and simple solutions

Treesearch

E. Ashley Steel; Maureen C. Kennedy; Patrick G. Cunningham; John S. Stanovick

2013-01-01

The most common statistical pitfalls in ecological research are those associated with data exploration, the logic of sampling and design, and the interpretation of statistical results. Although one can find published errors in calculations, the majority of statistical pitfalls result from incorrect logic or interpretation despite correct numerical calculations. There...

Methodological quality of behavioural weight loss studies: a systematic review

PubMed Central

Lemon, S. C.; Wang, M. L.; Haughton, C. F.; Estabrook, D. P.; Frisard, C. F.; Pagoto, S. L.

2018-01-01

Summary This systematic review assessed the methodological quality of behavioural weight loss intervention studies conducted among adults and associations between quality and statistically significant weight loss outcome, strength of intervention effectiveness and sample size. Searches for trials published between January, 2009 and December, 2014 were conducted using PUBMED, MEDLINE and PSYCINFO and identified ninety studies. Methodological quality indicators included study design, anthropometric measurement approach, sample size calculations, intent-to-treat (ITT) analysis, loss to follow-up rate, missing data strategy, sampling strategy, report of treatment receipt and report of intervention fidelity (mean = 6.3). Indicators most commonly utilized included randomized design (100%), objectively measured anthropometrics (96.7%), ITT analysis (86.7%) and reporting treatment adherence (76.7%). Most studies (62.2%) had a follow-up rate >75% and reported a loss to follow-up analytic strategy or minimal missing data (69.9%). Describing intervention fidelity (34.4%) and sampling from a known population (41.1%) were least common. Methodological quality was not associated with reporting a statistically significant result, effect size or sample size. This review found the published literature of behavioural weight loss trials to be of high quality for specific indicators, including study design and measurement. Identified for improvement include utilization of more rigorous statistical approaches to loss to follow up and better fidelity reporting. PMID:27071775

Is everything we eat associated with cancer? A systematic cookbook review.

PubMed

Schoenfeld, Jonathan D; Ioannidis, John P A

2013-01-01

Nutritional epidemiology is a highly prolific field. Debates on associations of nutrients with disease risk are common in the literature and attract attention in public media. We aimed to examine the conclusions, statistical significance, and reproducibility in the literature on associations between specific foods and cancer risk. We selected 50 common ingredients from random recipes in a cookbook. PubMed queries identified recent studies that evaluated the relation of each ingredient to cancer risk. Information regarding author conclusions and relevant effect estimates were extracted. When >10 articles were found, we focused on the 10 most recent articles. Forty ingredients (80%) had articles reporting on their cancer risk. Of 264 single-study assessments, 191 (72%) concluded that the tested food was associated with an increased (n = 103) or a decreased (n = 88) risk; 75% of the risk estimates had weak (0.05 > P ≥ 0.001) or no statistical (P > 0.05) significance. Statistically significant results were more likely than nonsignificant findings to be published in the study abstract than in only the full text (P < 0.0001). Meta-analyses (n = 36) presented more conservative results; only 13 (26%) reported an increased (n = 4) or a decreased (n = 9) risk (6 had more than weak statistical support). The median RRs (IQRs) for studies that concluded an increased or a decreased risk were 2.20 (1.60, 3.44) and 0.52 (0.39, 0.66), respectively. The RRs from the meta-analyses were on average null (median: 0.96; IQR: 0.85, 1.10). Associations with cancer risk or benefits have been claimed for most food ingredients. Many single studies highlight implausibly large effects, even though evidence is weak. Effect sizes shrink in meta-analyses.

The Extent and Consequences of P-Hacking in Science

PubMed Central

Head, Megan L.; Holman, Luke; Lanfear, Rob; Kahn, Andrew T.; Jennions, Michael D.

2015-01-01

A focus on novel, confirmatory, and statistically significant results leads to substantial bias in the scientific literature. One type of bias, known as “p-hacking,” occurs when researchers collect or select data or statistical analyses until nonsignificant results become significant. Here, we use text-mining to demonstrate that p-hacking is widespread throughout science. We then illustrate how one can test for p-hacking when performing a meta-analysis and show that, while p-hacking is probably common, its effect seems to be weak relative to the real effect sizes being measured. This result suggests that p-hacking probably does not drastically alter scientific consensuses drawn from meta-analyses. PMID:25768323

The effect of clulstering of galaxies on the statistics of gravitational lenses

NASA Technical Reports Server (NTRS)

Anderson, N.; Alcock, C.

1986-01-01

It is examined whether clustering of galaxies can significantly alter the statistical properties of gravitational lenses? Only models of clustering that resemble the observed distribution of galaxies in the properties of the two-point correlation function are considered. Monte-Carlo simulations of the imaging process are described. It is found that the effect of clustering is too small to be significant, unless the mass of the deflectors is so large that gravitational lenses become common occurrences. A special model is described which was concocted to optimize the effect of clustering on gravitational lensing but still resemble the observed distribution of galaxies; even this simulation did not satisfactorily produce large numbers of wide-angle lenses.

Antihistamines for the common cold.

PubMed

De Sutter, An I M; Saraswat, Avadhesh; van Driel, Mieke L

2015-11-29

The common cold is an upper respiratory tract infection, most commonly caused by a rhinovirus. It affects people of all age groups and although in most cases it is self limiting, the common cold still causes significant morbidity. Antihistamines are commonly offered over the counter to relieve symptoms for patients affected by the common cold, however there is not much evidence of their efficacy. To assess the effects of antihistamines on the common cold. We searched CENTRAL (2015, Issue 6), MEDLINE (1948 to July week 4, 2015), EMBASE (2010 to August 2015), CINAHL (1981 to August 2015), LILACS (1982 to August 2015) and Biosis Previews (1985 to August 2015). We selected randomised controlled trials (RCTs) using antihistamines as monotherapy for the common cold. We excluded any studies with combination therapy or using antihistamines in patients with an allergic component in their illness. Two authors independently assessed trial quality and extracted data. We collected adverse effects information from the included trials. We included 18 RCTs, which were reported in 17 publications (one publication reports on two trials) with 4342 participants (of which 212 were children) suffering from the common cold, both naturally occurring and experimentally induced. The interventions consisted of an antihistamine as monotherapy compared with placebo. In adults there was a short-term beneficial effect of antihistamines on severity of overall symptoms: on day one or two of treatment 45% had a beneficial effect with antihistamines versus 38% with placebo (odds ratio (OR) 0.74, 95% confidence interval (CI) 0.60 to 0.92). However, there was no difference between antihistamines and placebo in the mid term (three to four days) to long term (six to 10 days). When evaluating individual symptoms such as nasal congestion, rhinorrhoea and sneezing, there was some beneficial effect of the sedating antihistamines compared to placebo (e.g. rhinorrhoea on day three: mean difference (MD) -0.23, 95% CI -0.39 to -0.06 on a four- or five-point severity scale; sneezing on day three: MD -0.35, 95% CI -0.49 to -0.20 on a four-point severity scale), but this effect is clinically non-significant. Adverse events such as sedation were more commonly reported with sedating antihistamines although the differences were not statistically significant. Only two trials included children and the results were conflicting. The majority of the trials had a low risk of bias although some lacked sufficient trial quality information. Antihistamines have a limited short-term (days one and two of treatment) beneficial effect on severity of overall symptoms but not in the mid to long term. There is no clinically significant effect on nasal obstruction, rhinorrhoea or sneezing. Although side effects are more common with sedating antihistamines, the difference is not statistically significant. There is no evidence of effectiveness of antihistamines in children.

Approaches to Art Therapy for Cancer Inpatients: Research and Practice Considerations

ERIC Educational Resources Information Center

Nainis, Nancy A.

2008-01-01

Common symptoms reported by cancer patients include pain, fatigue, breathlessness, insomnia, lack of appetite, and anxiety. A study conducted by an interdisciplinary research team (Nainis et al., 2006) demonstrated statistically significant reductions in these cancer symptoms with the use of traditional art therapy methods. The study found a…

Metabolic Syndrome in Psoriasis among Urban South Indians: A Case Control Study Using SAM-NCEP Criteria.

PubMed

Girisha, Banavasi S; Thomas, Neetha

2017-02-01

Psoriasis is a chronic inflammatory disease of the skin associated with increased cardiovascular morbidity. Metabolic syndrome is a significant forecaster of cardiovascular events. To assess the association of metabolic syndrome and its components in patients with psoriasis and to compare it with the age and sex matched control group. We conducted a hospital based case-control study on 156 adult patients with chronic plaque psoriasis and 156 patients with skin diseases other than psoriasis. Height, weight, BMI, blood pressure and waist circumference were documented in all the subjects. Fasting levels of serum glucose, serum triglycerides and serum HDL were estimated by automated clinical chemistry analyzer. The South Asian modified NCEP ATP criterion was used for the diagnosis of metabolic syndrome. Statistical analysis of the data was done using statistical processing software (SPSS-17). Metabolic syndrome was significantly more common in psoriatic patients than in controls (28.8% vs 16.7%, p=0.01). Hypertriglyceridemia was significantly more prevalent in cases than in controls (34% vs 20.5%, p=0.008). The reduced HDL levels also showed a significantly high occurrence among cases (27.6% vs 13.5%, p=0.002). Moderate increase of blood pressure was seen among cases as compared to controls but the difference was not statistically significant (p=0.1). Impaired blood glucose and abdominal obesity were similar in both groups. Smoking and alcoholism did not influence the association of metabolic syndrome with psoriasis. There was no correlation of metabolic syndrome with severity and duration of psoriasis. Our findings suggest that metabolic syndrome as well as dyslipidemia is common in psoriasis patients among urban South Indians. This study highlights the need for screening at diagnosis and regular follow up of the metabolic aspects of the disease along with the skin lesions.

Use of apron flap incision for neck dissection.

PubMed

Yii, N W; Patel, S G; Williamson, P; Breach, N M

1999-05-01

Neck dissection is one of the most commonly performed surgical procedures in the management of head and neck cancer. Different skin incisions with various modifications have been described in the literature. Three commonly used but conceptually different incisions were compared with respect to the incidence of wound dehiscence in a retrospective review. There were 166 patients with 184 neck dissections carried out using a triradiate (n = 85), modified MacFee (n = 25), or an apron flap incision (n = 74). The incidence of wound dehiscence in the three groups was 11 percent, 8 percent, and 0 percent for the triradiate, modified MacFee, and apron flap incisions, respectively. There was a statistically significant difference in the incidence of wound dehiscence between the apron flap incision and the triradiate incision groups (p = 0.004). The difference in wound dehiscence was not statistically significant between the apron flap incision and the modified MacFee incision groups (p = 0.06). Overall, there was a significant increase in the incidence of wound dehiscence in previously irradiated necks (p = 0.02), but this was significant only for the triradiate incision (p = 0.005) when analyzed individually. Comparison of triradiate, apron, and MacFee incisions did not show a statistically significant difference between the incisions with regard to other postoperative complications in terms of seroma, hematoma, wound infection, and fistula formation. The apron flap incision is the recommended approach in the presence of previous neck irradiation as it gives easier access than the MacFee incision. The robustness of the flap is because of the absence of a trifurcate point as well as a good vascular supply arising from arterial territory of the external carotid artery.

On representing the prognostic value of continuous gene expression biomarkers with the restricted mean survival curve.

PubMed

Eng, Kevin H; Schiller, Emily; Morrell, Kayla

2015-11-03

Researchers developing biomarkers for cancer prognosis from quantitative gene expression data are often faced with an odd methodological discrepancy: while Cox's proportional hazards model, the appropriate and popular technique, produces a continuous and relative risk score, it is hard to cast the estimate in clear clinical terms like median months of survival and percent of patients affected. To produce a familiar Kaplan-Meier plot, researchers commonly make the decision to dichotomize a continuous (often unimodal and symmetric) score. It is well known in the statistical literature that this procedure induces significant bias. We illustrate the liabilities of common techniques for categorizing a risk score and discuss alternative approaches. We promote the use of the restricted mean survival (RMS) and the corresponding RMS curve that may be thought of as an analog to the best fit line from simple linear regression. Continuous biomarker workflows should be modified to include the more rigorous statistical techniques and descriptive plots described in this article. All statistics discussed can be computed via standard functions in the Survival package of the R statistical programming language. Example R language code for the RMS curve is presented in the appendix.

Understanding common statistical methods, Part I: descriptive methods, probability, and continuous data.

PubMed

Skinner, Carl G; Patel, Manish M; Thomas, Jerry D; Miller, Michael A

2011-01-01

Statistical methods are pervasive in medical research and general medical literature. Understanding general statistical concepts will enhance our ability to critically appraise the current literature and ultimately improve the delivery of patient care. This article intends to provide an overview of the common statistical methods relevant to medicine.

A Comparison of Analytical and Data Preprocessing Methods for Spectral Fingerprinting

PubMed Central

LUTHRIA, DEVANAND L.; MUKHOPADHYAY, SUDARSAN; LIN, LONG-ZE; HARNLY, JAMES M.

2013-01-01

Spectral fingerprinting, as a method of discriminating between plant cultivars and growing treatments for a common set of broccoli samples, was compared for six analytical instruments. Spectra were acquired for finely powdered solid samples using Fourier transform infrared (FT-IR) and Fourier transform near-infrared (NIR) spectrometry. Spectra were also acquired for unfractionated aqueous methanol extracts of the powders using molecular absorption in the ultraviolet (UV) and visible (VIS) regions and mass spectrometry with negative (MS−) and positive (MS+) ionization. The spectra were analyzed using nested one-way analysis of variance (ANOVA) and principal component analysis (PCA) to statistically evaluate the quality of discrimination. All six methods showed statistically significant differences between the cultivars and treatments. The significance of the statistical tests was improved by the judicious selection of spectral regions (IR and NIR), masses (MS+ and MS−), and derivatives (IR, NIR, UV, and VIS). PMID:21352644

Biostatistics primer: part I.

PubMed

Overholser, Brian R; Sowinski, Kevin M

2007-12-01

Biostatistics is the application of statistics to biologic data. The field of statistics can be broken down into 2 fundamental parts: descriptive and inferential. Descriptive statistics are commonly used to categorize, display, and summarize data. Inferential statistics can be used to make predictions based on a sample obtained from a population or some large body of information. It is these inferences that are used to test specific research hypotheses. This 2-part review will outline important features of descriptive and inferential statistics as they apply to commonly conducted research studies in the biomedical literature. Part 1 in this issue will discuss fundamental topics of statistics and data analysis. Additionally, some of the most commonly used statistical tests found in the biomedical literature will be reviewed in Part 2 in the February 2008 issue.

Frequency of Toxocariasis among Patients Clinically Suspected to Have Visceral Toxocariasis: A Retrospective Descriptive Study in Sri Lanka

PubMed Central

Iddawela, Devika; Ehambaram, Kiruthiha; Pethiyagoda, Kalyani; Bandara, Lakmalee

2017-01-01

Introduction Human toxocariasis is caused by several species of the nematode Toxocara. Two common clinical syndromes are ocular and visceral larva migrans. Objectives To determine the Toxocara antibody positivity in clinically suspected VLM patients and to describe demographic factors and clinical manifestations of seropositive patients. Methods 522 clinically suspected patients were studied between 1993 and 2014. Relevant data was gathered from referral letters. Serum samples were subjected to Toxocara antigen ELISA. Results Overall, seropositivity was 50.2% (262), of which 109 (40.8%) were positive at high level of Toxocara antibody carriage and 153 (58.4%) were positive at low levels. The seropositives ranged from 3 months to 70 years (mean = 7.8). Younger age group had higher levels of seropositivity and it was statistically significant. Majority of children under 5 years were seropositive (47.7%, n = 125). Seropositivity was common in males (55.3%, n = 145). Clinical manifestations of seropositives include lymphadenopathy (24.1%) skin rash (22.5%), dyspnoea (21.7%), fever (21%), hepatosplenomegaly (9.2%), and abdominal pain (3.8%). 197 (75.2%) seropositive cases had eosinophilia. These symptoms were not statistically significant. Conclusions This study confirms toxocariasis as an important cause of childhood ill health identifying common clinical symptoms recommending preventive measures to limit transmission. PMID:29362672

Epidemiology of Rett syndrome in Serbia: prevalence, incidence and survival.

PubMed

Sarajlija, Adrijan; Kisic-Tepavcevic, Darija; Nikolic, Zorana; Savic Pavicevic, Dusanka; Obradovic, Slobodan; Djuric, Milena; Pekmezovic, Tatjana

2015-01-01

Rett syndrome (RTT) is a severe neurodevelopmental disorder that represents the second most common cause of mental retardation in females. However, incidence and prevalence of RTT are scarcely reported. A retrospective study included all patients with RTT diagnosed between 1981 and 2012 in Serbia. Estimation of incidence and prevalence was calculated on the basis of vital statistics reported by Statistical Office of Republic of Serbia. From 1981 to 2012, RTT has been diagnosed in 102 girls in Serbia. Incidence of RTT in Serbia is estimated at 0.586:10,000 female live births. We estimated the prevalence of RTT in population of females younger than 19 years at 1:8,439. Death occurred in 19 patients (18.63%), with pneumonia as the most common cause. The lethal outcome by the age of 12 years could be expected for 11% of patients. The mean age at diagnosis was 3.5 years and we have confirmed a significant trend towards earlier dianosis during studied period. Rett syndrome incidence in Serbia is in accordance with reports from other countries. Serbian RTT patients have increased risk for early death when compared to patients in more developed countries, most commonly due to pneumonia. There was significant trend towards early diagnosis of RTT in Serbia over recent decades. © 2015 S. Karger AG, Basel.

Malignant pleural effusions and the role of talc poudrage and talc slurry: a systematic review and meta-analysis

PubMed Central

Mummadi, Srinivas; Kumbam, Anusha; Hahn, Peter Y.

2015-01-01

Background: Malignant Pleural Effusion (MPE) is common with advanced malignancy. Palliative care with minimal adverse events is the cornerstone of management. Although talc pleurodesis plays an important role in treatment, the best modality of talc application remains controversial.   Objective: To compare rates of successful pleurodesis, rates of respiratory and non-respiratory complications between thoracoscopic talc insufflation/poudrage (TTI) and talc slurry (TS).  Data sources and study selection: MEDLINE (PubMed, OVID),  EBM Reviews (Cochrane database of Systematic Reviews, ACP Journal Club, DARE, Cochrane Central Register of Controlled Trials, Cochrane Methodology Register, Health Technology Assessment and NHS Economic Evaluation Database), EMBASE and Scopus. Randomized controlled trials published between 01/01/1980 - 10/1/2014 and comparing the two strategies were selected.  Results: Twenty-eight potential studies were identified of which 24 studies were further excluded, leaving four studies. No statistically significant difference in the probability of successful pleurodesis was observed between TS and TTI groups (RR 1.06; 95 % CI 0.99-1.14; Q statistic, 4.84). There was a higher risk of post procedural respiratory complications in the TTI group compared to the TS group (RR 1.91, 95% CI= 1.24-2.93, Q statistic 3.15). No statistically significant difference in the incidence of non-respiratory complications between the TTI group and the TS group was observed (RR 0.88, 95% CI= 0.72-1.07, Q statistic 4.61). Conclusions: There is no difference in success rates of pleurodesis based on patient centered outcomes between talc poudrage and talc slurry treatments.  Respiratory complications are more common with talc poudrage via thoracoscopy. PMID:25878773

Statistical analysis of co-occurrence patterns in microbial presence-absence datasets.

PubMed

Mainali, Kumar P; Bewick, Sharon; Thielen, Peter; Mehoke, Thomas; Breitwieser, Florian P; Paudel, Shishir; Adhikari, Arjun; Wolfe, Joshua; Slud, Eric V; Karig, David; Fagan, William F

2017-01-01

Drawing on a long history in macroecology, correlation analysis of microbiome datasets is becoming a common practice for identifying relationships or shared ecological niches among bacterial taxa. However, many of the statistical issues that plague such analyses in macroscale communities remain unresolved for microbial communities. Here, we discuss problems in the analysis of microbial species correlations based on presence-absence data. We focus on presence-absence data because this information is more readily obtainable from sequencing studies, especially for whole-genome sequencing, where abundance estimation is still in its infancy. First, we show how Pearson's correlation coefficient (r) and Jaccard's index (J)-two of the most common metrics for correlation analysis of presence-absence data-can contradict each other when applied to a typical microbiome dataset. In our dataset, for example, 14% of species-pairs predicted to be significantly correlated by r were not predicted to be significantly correlated using J, while 37.4% of species-pairs predicted to be significantly correlated by J were not predicted to be significantly correlated using r. Mismatch was particularly common among species-pairs with at least one rare species (<10% prevalence), explaining why r and J might differ more strongly in microbiome datasets, where there are large numbers of rare taxa. Indeed 74% of all species-pairs in our study had at least one rare species. Next, we show how Pearson's correlation coefficient can result in artificial inflation of positive taxon relationships and how this is a particular problem for microbiome studies. We then illustrate how Jaccard's index of similarity (J) can yield improvements over Pearson's correlation coefficient. However, the standard null model for Jaccard's index is flawed, and thus introduces its own set of spurious conclusions. We thus identify a better null model based on a hypergeometric distribution, which appropriately corrects for species prevalence. This model is available from recent statistics literature, and can be used for evaluating the significance of any value of an empirically observed Jaccard's index. The resulting simple, yet effective method for handling correlation analysis of microbial presence-absence datasets provides a robust means of testing and finding relationships and/or shared environmental responses among microbial taxa.

Hidden Hearing Loss? No Effect of Common Recreational Noise Exposure on Cochlear Nerve Response Amplitude in Humans

PubMed Central

Grinn, Sarah K.; Wiseman, Kathryn B.; Baker, Jason A.; Le Prell, Colleen G.

2017-01-01

This study tested hypothesized relationships between noise exposure and auditory deficits. Both retrospective assessment of potential associations between noise exposure history and performance on an audiologic test battery and prospective assessment of potential changes in performance after new recreational noise exposure were completed. Methods: 32 participants (13M, 19F) with normal hearing (25-dB HL or better, 0.25–8 kHz) were asked to participate in 3 pre- and post-exposure sessions including: otoscopy, tympanometry, distortion product otoacoustic emissions (DPOAEs) (f2 frequencies 1–8 kHz), pure-tone audiometry (0.25–8 kHz), Words-in-Noise (WIN) test, and electrocochleography (eCochG) measurements at 70, 80, and 90-dB nHL (click and 2–4 kHz tone-bursts). The first session was used to collect baseline data, the second session was collected the day after a loud recreational event, and the third session was collected 1-week later. Of the 32 participants, 26 completed all 3 sessions. Results: The retrospective analysis did not reveal statistically significant relationships between noise exposure history and any auditory deficits. The day after new exposure, there was a statistically significant correlation between noise “dose” and WIN performance overall, and within the 4-dB signal-to-babble ratio. In contrast, there were no statistically significant correlations between noise dose and changes in threshold, DPOAE amplitude, or AP amplitude the day after new noise exposure. Additional analyses revealed a statistically significant relationship between TTS and DPOAE amplitude at 6 kHz, with temporarily decreased DPOAE amplitude observed with increasing TTS. Conclusions: There was no evidence of auditory deficits as a function of previous noise exposure history, and no permanent changes in audiometric, electrophysiologic, or functional measures after new recreational noise exposure. There were very few participants with TTS the day after exposure - a test time selected to be consistent with previous animal studies. The largest observed TTS was approximately 20-dB. The observed pattern of small TTS suggests little risk of synaptopathy from common recreational noise exposure, and that we should not expect to observe changes in evoked potentials for this reason. No such changes were observed in this study. These data do not support suggestions that common, recreational noise exposure is likely to result in “hidden hearing loss”. PMID:28919848

How to get statistically significant effects in any ERP experiment (and why you shouldn't).

PubMed

Luck, Steven J; Gaspelin, Nicholas

2017-01-01

ERP experiments generate massive datasets, often containing thousands of values for each participant, even after averaging. The richness of these datasets can be very useful in testing sophisticated hypotheses, but this richness also creates many opportunities to obtain effects that are statistically significant but do not reflect true differences among groups or conditions (bogus effects). The purpose of this paper is to demonstrate how common and seemingly innocuous methods for quantifying and analyzing ERP effects can lead to very high rates of significant but bogus effects, with the likelihood of obtaining at least one such bogus effect exceeding 50% in many experiments. We focus on two specific problems: using the grand-averaged data to select the time windows and electrode sites for quantifying component amplitudes and latencies, and using one or more multifactor statistical analyses. Reanalyses of prior data and simulations of typical experimental designs are used to show how these problems can greatly increase the likelihood of significant but bogus results. Several strategies are described for avoiding these problems and for increasing the likelihood that significant effects actually reflect true differences among groups or conditions. © 2016 Society for Psychophysiological Research.

How to Get Statistically Significant Effects in Any ERP Experiment (and Why You Shouldn’t)

PubMed Central

Luck, Steven J.; Gaspelin, Nicholas

2016-01-01

Event-related potential (ERP) experiments generate massive data sets, often containing thousands of values for each participant, even after averaging. The richness of these data sets can be very useful in testing sophisticated hypotheses, but this richness also creates many opportunities to obtain effects that are statistically significant but do not reflect true differences among groups or conditions (bogus effects). The purpose of this paper is to demonstrate how common and seemingly innocuous methods for quantifying and analyzing ERP effects can lead to very high rates of significant-but-bogus effects, with the likelihood of obtaining at least one such bogus effect exceeding 50% in many experiments. We focus on two specific problems: using the grand average data to select the time windows and electrode sites for quantifying component amplitudes and latencies, and using one or more multi-factor statistical analyses. Re-analyses of prior data and simulations of typical experimental designs are used to show how these problems can greatly increase the likelihood of significant-but-bogus results. Several strategies are described for avoiding these problems and for increasing the likelihood that significant effects actually reflect true differences among groups or conditions. PMID:28000253

Initial Experience with Balloon-Occluded Trans-catheter Arterial Chemoembolization (B-TACE) for Hepatocellular Carcinoma

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

Maruyama, Mitsunari, E-mail: mitunari@med-shimane.u.ac.jp; Yoshizako, Takeshi, E-mail: yosizako@med.shimane-u.ac.jp; Nakamura, Tomonori, E-mail: t-naka@med.shimane-u.ac.jp

2016-03-15

PurposeThis study was performed to evaluate the accumulation of lipiodol emulsion (LE) and adverse events during our initial experience of balloon-occluded trans-catheter arterial chemoembolization (B-TACE) for hepatocellular carcinoma (HCC) compared with conventional TACE (C-TACE).MethodsB-TACE group (50 cases) was compared with C-TACE group (50 cases). The ratio of the LE concentration in the tumor to that in the surrounding embolized liver parenchyma (LE ratio) was calculated after each treatment. Adverse events were evaluated according to the Common Terminology Criteria for Adverse Effects (CTCAE) version 4.0.ResultsThe LE ratio at the level of subsegmental showed a statistically significant difference between the groups (tmore » test: P < 0.05). Only elevation of alanine aminotransferase was more frequent in the B-TACE group, showing a statistically significant difference (Mann–Whitney test: P < 0.05). While B-TACE caused severe adverse events (liver abscess and infarction) in patients with bile duct dilatation, there was no statistically significant difference in incidence between the groups. Multivariate logistic regression analysis suggested that the significant risk factor for liver abscess/infarction was bile duct dilatation (P < 0.05).ConclusionThe LE ratio at the level of subsegmental showed a statistically significant difference between the groups (t test: P < 0.05). B-TACE caused severe adverse events (liver abscess and infarction) in patients with bile duct dilatation.« less

Population genetics of apolipoprotein A-4, E, and H polymorphisms in Yanomami Indians of northwestern Brazil: associations with lipids, lipoproteins, and carbohydrate metabolism.

PubMed

Crews, D E; Kamboh, M I; Mancilha-Carvalho, J J; Kottke, B

1993-04-01

Using isoelectric focusing and immunoblotting techniques, we screened 96 serum samples from Yanomami Indians of northwestern Brazil to determine structural variation at three apolipoprotein loci: A4, E, and H. The APO-H locus, which is commonly polymorphic in white and black samples, was found to be monomorphic. At the APO-E locus only two alleles, APOE*3 and APOE*4, rather than the three-allele polymorphism commonly seen in Caucasians, was observed. At the APO-A4 locus no example of the APOA4*2 allele, found in Caucasians, was detected. However, the frequency of the less common APOA4*4 allele was above what has been observed in any other population. We investigated the impact of genetic variation at both polymorphic loci on quantitative differences in lipids, apolipoproteins, serum glucose, glycated hemoglobin, and uric acid. Contrary to the cholesterol-elevating effect of APOE*4 reported elsewhere, in both univariate analyses and after adjustments for age, sex, weight, and height, APOE*4 was associated with about a 4% lower mean serum cholesterol. Only after adjustment was this association statistically significant. The APOE*4 allele was significantly associated with unadjusted APO-A1 and APO-E levels but not with any other dependent variable; associations with adjusted APO-A1, APO-C2, and uric acid also approached standard levels of statistical significance (p < or = 0.05). In univariate analyses the APOA4*4 allele was significantly associated with APO-B, serum glucose, percent glycated hemoglobin, and uric acid, but no significant associations were observed after dependent variables were adjusted for age, sex, weight, and height. These results support the notion that apolipoprotein distributions and their associations with lipid and carbohydrate metabolism show ethnic variability.

Statistics Refresher for Molecular Imaging Technologists, Part 2: Accuracy of Interpretation, Significance, and Variance.

PubMed

Farrell, Mary Beth

2018-06-01

This article is the second part of a continuing education series reviewing basic statistics that nuclear medicine and molecular imaging technologists should understand. In this article, the statistics for evaluating interpretation accuracy, significance, and variance are discussed. Throughout the article, actual statistics are pulled from the published literature. We begin by explaining 2 methods for quantifying interpretive accuracy: interreader and intrareader reliability. Agreement among readers can be expressed simply as a percentage. However, the Cohen κ-statistic is a more robust measure of agreement that accounts for chance. The higher the κ-statistic is, the higher is the agreement between readers. When 3 or more readers are being compared, the Fleiss κ-statistic is used. Significance testing determines whether the difference between 2 conditions or interventions is meaningful. Statistical significance is usually expressed using a number called a probability ( P ) value. Calculation of P value is beyond the scope of this review. However, knowing how to interpret P values is important for understanding the scientific literature. Generally, a P value of less than 0.05 is considered significant and indicates that the results of the experiment are due to more than just chance. Variance, standard deviation (SD), confidence interval, and standard error (SE) explain the dispersion of data around a mean of a sample drawn from a population. SD is commonly reported in the literature. A small SD indicates that there is not much variation in the sample data. Many biologic measurements fall into what is referred to as a normal distribution taking the shape of a bell curve. In a normal distribution, 68% of the data will fall within 1 SD, 95% will fall within 2 SDs, and 99.7% will fall within 3 SDs. Confidence interval defines the range of possible values within which the population parameter is likely to lie and gives an idea of the precision of the statistic being measured. A wide confidence interval indicates that if the experiment were repeated multiple times on other samples, the measured statistic would lie within a wide range of possibilities. The confidence interval relies on the SE. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.

Prevalence of common mental disorders among sugarcane workers.

PubMed

Costa, Polyana Felipe Ferreira da; Santos, Solange Laurentino Dos; Silva, Marcelo Saturnino da; Gurgel, Idê Gomes Dantas

2017-12-11

To estimate the prevalence of common mental disorders and to analyze the associated factors in migrant and sugarcane workers. This is a cross-sectional study carried out with 110 workers. Common mental disorders were evaluated using the Self-Reporting Questionnaire (SRQ-20), and sociodemographic, occupational, and lifestyle variables were studied. The CAGE questionnaire was used to detect the abuse of alcoholic beverages. The prevalence of common mental disorders affected 40% of the workers and the association showed statistical significance for the positive result of the CAGE test, sickness, absence from work, and medical care during the harvest period. The suspected cases of problem drinkers and the control mechanisms used by the mill for workers who miss work or become ill are factors that can cause common mental disorders.

Male reproductive health under threat: Short term exposure to radiofrequency radiations emitted by common mobile jammers

PubMed Central

Mortazavi, SMJ; Parsanezhad, ME; Kazempour, M; Ghahramani, P; Mortazavi, AR; Davari, M

2013-01-01

BACKGROUND: Modern life prompted man to increasingly generate, transmit and use electricity that leads to exposure to different levels of electromagnetic fields (EMFs). Substantial evidence indicates that exposure to common sources of EMF such as mobile phones, laptops or wireless internet-connected laptops decreases human semen quality. In some countries, mobile jammers are occasionally used in offices, shrines, conference rooms and cinemas to block the signal. AIMS: To the best of our knowledge, this is the first study to investigate the effect of short term exposure of human sperm samples to radiofrequency (RF) radiations emitted by common mobile jammers. SUBJECTS AND METHODS: Fresh semen samples were collected by masturbation from 30 healthy donors who had referred to Infertility Treatment Center at the Mother and Child Hospital with their wives. Female problem was diagnosed as the reason for infertility in these couples. STATISTICAL ANALYSIS: T-test and analysis of variance were used to show statistical significance. RESULTS: The motility of sperm samples exposed to jammer RF radiation for 2 or 4 h were significantly lower than those of sham-exposed samples. These findings lead us to the conclusion that mobile jammers may significantly decrease sperm motility and the couples’ chances of conception. CONCLUSION: Based on these results, it can be suggested that in countries that have not banned mobile jammer use, legislations should be urgently passed to restrict the use of these signal blocking devices in public or private places. PMID:24082653

Dermatological Manifestations in Patients Undergoing In Vitro Fertilisation: A Prospective Study.

PubMed

Sood, Aradhana; Sahu, Suvash; Karunakaran, Sandeep; Joshi, Rajneesh K; Raman, Deep Kumar

Changing sociodemographic patterns with an increase in the age of childbirth have affected fertility rates worldwide. With advancing reproductive medicine, assisted reproductive techniques (ARTs) are becoming common. While dermatological manifestations in normal pregnancies have been well documented, there is a paucity of data regarding cutaneous manifestations in patients undergoing ART. The objectives of our study were to estimate the incidence and types of dermatological manifestations in patients undergoing in vitro fertilisation (IVF) and to study their associations with age, type of infertility, and outcome of the procedure. A prospective cohort of 200 patients undergoing IVF in a tertiary care centre was observed for occurrence of any dermatological manifestations from initiation of the IVF protocol to the outcome of the procedure at 3 weeks after embryo transfer. Dermatological manifestations were seen in 27% of the study group, with urticaria being the most common cutaneous finding seen in 13.5%, followed by acneform eruptions (3%). Twenty-six (96.3%) of patients who manifested with urticaria were on progesterone. No statistically significant association was found between the occurrence of dermatological manifestations and the outcome of IVF, type of infertility, history of ART, and ovum donation in our study. Association between the age of the patient and the outcome of IVF cycle was statistically significant. Dermatological manifestations are seen in almost one-quarter of patients undergoing IVF, with progesterone-induced urticaria being the most common. Occurrence of cutaneous manifestations has no significant association with the outcome of IVF.

Zinc for the common cold.

PubMed

Singh, Meenu; Das, Rashmi R

2013-06-18

The common cold is one of the most widespread illnesses and is a leading cause of visits to the doctor and absenteeism from school and work. Trials conducted in high-income countries since 1984 investigating the role of zinc for the common cold symptoms have had mixed results. Inadequate treatment masking and reduced bioavailability of zinc from some formulations have been cited as influencing results. To assess whether zinc (irrespective of the zinc salt or formulation used) is efficacious in reducing the incidence, severity and duration of common cold symptoms. In addition, we aimed to identify potential sources of heterogeneity in results obtained and to assess their clinical significance. In this updated review, we searched CENTRAL (2012, Issue 12), MEDLINE (1966 to January week 2, 2013), EMBASE (1974 to January 2013), CINAHL (1981 to January 2013), Web of Science (1985 to January 2013), LILACS (1982 to January 2013), WHO ICTRP and clinicaltrials.gov. Randomised, double-blind, placebo-controlled trials using zinc for at least five consecutive days to treat, or for at least five months to prevent the common cold. Two review authors independently extracted data and assessed trial quality. Five trials were identified in the updated searches in January 2013 and two of them did not meet our inclusion criteria. We included 16 therapeutic trials (1387 participants) and two preventive trials (394 participants). Intake of zinc was associated with a significant reduction in the duration (days) (mean difference (MD) -1.03, 95% confidence interval (CI) -1.72 to -0.34) (P = 0.003) (I(2) statistic = 89%) but not the severity of common cold symptoms (MD -1.06, 95% CI -2.36 to 0.23) (P = 0.11) (I(2) statistic = 84%). The proportion of participants who were symptomatic after seven days of treatment was significantly smaller (odds ratio (OR) 0.45, 95% CI 0.20 to 1.00) (P = 0.05) than those in the control, (I(2 )statistic = 75%). The incidence rate ratio (IRR) of developing a cold (IRR 0.64, 95% CI 0.47 to 0.88) (P = 0.006) (I(2) statistic = 88%), school absence (P = 0.0003) and prescription of antibiotics (P < 0.00001) was lower in the zinc group. Overall adverse events (OR 1.58, 95% CI 1.19 to 2.09) (P = 0.002), bad taste (OR 2.31, 95% CI 1.71 to 3.11) (P < 0.00001) and nausea (OR 2.15, 95% CI 1.44 to 3.23) (P = 0.002) were higher in the zinc group. The very high heterogeneity means that the averaged estimates must be viewed with caution. Zinc administered within 24 hours of onset of symptoms reduces the duration of common cold symptoms in healthy people but some caution is needed due to the heterogeneity of the data. As the zinc lozenges formulation has been widely studied and there is a significant reduction in the duration of cold at a dose of ≥ 75 mg/day, for those considering using zinc it would be best to use it at this dose throughout the cold. Regarding prophylactic zinc supplementation, currently no firm recommendation can be made because of insufficient data. When using zinc lozenges (not as syrup or tablets) the likely benefit has to be balanced against side effects, notably a bad taste and nausea.

Improved method for reliable HMW-GS identification by RP-HPLC and SDS-PAGE in common wheat cultivars

USDA-ARS?s Scientific Manuscript database

The accurate identification of alleles for high-molecular weight glutenins (HMW-GS) is critical for wheat breeding programs targeting end-use quality. RP-HPLC methods were optimized for separation of HMW-GS, resulting in enhanced resolution of 1By and 1Dx subunits. Statistically significant differe...

Ranking Bias in Association Studies

PubMed Central

Jeffries, Neal O.

2009-01-01

Background It is widely appreciated that genomewide association studies often yield overestimates of the association of a marker with disease when attention focuses upon the marker showing the strongest relationship. For example, in a case-control setting the largest (in absolute value) estimated odds ratio has been found to typically overstate the association as measured in a second, independent set of data. The most common reason given for this observation is that the choice of the most extreme test statistic is often conditional upon first observing a significant p value associated with the marker. A second, less appreciated reason is described here. Under common circumstances it is the multiple testing of many markers and subsequent focus upon those with most extreme test statistics (i.e. highly ranked results) that leads to bias in the estimated effect sizes. Conclusions This bias, termed ranking bias, is separate from that arising from conditioning on a significant p value and may often be a more important factor in generating bias. An analytic description of this bias, simulations demonstrating its extent, and identification of some factors leading to its exacerbation are presented. PMID:19172085

A scan statistic to extract causal gene clusters from case-control genome-wide rare CNV data.

PubMed

Nishiyama, Takeshi; Takahashi, Kunihiko; Tango, Toshiro; Pinto, Dalila; Scherer, Stephen W; Takami, Satoshi; Kishino, Hirohisa

2011-05-26

Several statistical tests have been developed for analyzing genome-wide association data by incorporating gene pathway information in terms of gene sets. Using these methods, hundreds of gene sets are typically tested, and the tested gene sets often overlap. This overlapping greatly increases the probability of generating false positives, and the results obtained are difficult to interpret, particularly when many gene sets show statistical significance. We propose a flexible statistical framework to circumvent these problems. Inspired by spatial scan statistics for detecting clustering of disease occurrence in the field of epidemiology, we developed a scan statistic to extract disease-associated gene clusters from a whole gene pathway. Extracting one or a few significant gene clusters from a global pathway limits the overall false positive probability, which results in increased statistical power, and facilitates the interpretation of test results. In the present study, we applied our method to genome-wide association data for rare copy-number variations, which have been strongly implicated in common diseases. Application of our method to a simulated dataset demonstrated the high accuracy of this method in detecting disease-associated gene clusters in a whole gene pathway. The scan statistic approach proposed here shows a high level of accuracy in detecting gene clusters in a whole gene pathway. This study has provided a sound statistical framework for analyzing genome-wide rare CNV data by incorporating topological information on the gene pathway.

Dose fractionation theorem in 3-D reconstruction (tomography)

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

Glaeser, R.M.

It is commonly assumed that the large number of projections for single-axis tomography precludes its application to most beam-labile specimens. However, Hegerl and Hoppe have pointed out that the total dose required to achieve statistical significance for each voxel of a computed 3-D reconstruction is the same as that required to obtain a single 2-D image of that isolated voxel, at the same level of statistical significance. Thus a statistically significant 3-D image can be computed from statistically insignificant projections, as along as the total dosage that is distributed among these projections is high enough that it would have resultedmore » in a statistically significant projection, if applied to only one image. We have tested this critical theorem by simulating the tomographic reconstruction of a realistic 3-D model created from an electron micrograph. The simulations verify the basic conclusions of high absorption, signal-dependent noise, varying specimen contrast and missing angular range. Furthermore, the simulations demonstrate that individual projections in the series of fractionated-dose images can be aligned by cross-correlation because they contain significant information derived from the summation of features from different depths in the structure. This latter information is generally not useful for structural interpretation prior to 3-D reconstruction, owing to the complexity of most specimens investigated by single-axis tomography. These results, in combination with dose estimates for imaging single voxels and measurements of radiation damage in the electron microscope, demonstrate that it is feasible to use single-axis tomography with soft X-ray microscopy of frozen-hydrated specimens.« less

[Legal medicine specialists within the framework of acute care : Analysis of legal medicine consultations in relation to the victims' statistics of the state office of criminal investigation in Saxony-Anhalt].

PubMed

Pliske, G; Heide, S; Lucas, B; Brandstädter, K; Walcher, F; Kropf, S; Lessig, R; Piatek, S

2018-05-01

In acute medical care, there are patients who have been injured by the influence of others. The aim of this study was to analyze all cases which were presented to the Institute for Legal Medicine of the University Halle (Saale). The cases where analyzed in relation to the victims' statistics of the state office of criminal investigation in Saxony-Anhalt. The consultations of the Institute for Legal Medicine Halle-Wittenberg for 2012-2015 were evaluated with regard to the age and gender distribution, the reasons for the consultation and time until the request for consultations. These cases were statistically compared to the victims' statistics of the state office of criminal investigation in Saxony-Anhalt 2014-2015. A total of 536 cases (55.6% male and 44.4% female patients) were evaluated. In all, 62.1% of patients were under 18 years of age; 43.5% of all consultations were requested by pediatric (surgery) clinics. The most common reasons for consultation were sexual child abuse or violence against children (50.7%). Compared to the victims' statistics, significantly more children were examined by legal medicine specialists than could have been expected (p < 0.001). In adult patients, the most common causes for consultation were acts of violence (20.4%) and domestic violence (10.1%). Among adults, significantly more women and fewer men were presented than expected (p = 0.001). There were only a small number of consultations of legal medicine specialists in relation to the victims' statistics. Most of them were children and women. The temporal latency between the act of violence and the consultations was one day and more. The latency and the renunciation of the consultation of the legal medicine specialists can lead to loss of evidence.

Sequence variants of Toll-like receptor 4 and susceptibility to prostate cancer.

PubMed

Chen, Yen-Ching; Giovannucci, Edward; Lazarus, Ross; Kraft, Peter; Ketkar, Shamika; Hunter, David J

2005-12-15

Chronic inflammation has been hypothesized to be a risk factor for prostate cancer. The Toll-like receptor 4 (TLR4) presents the bacterial lipopolysaccharide (LPS), which interacts with ligand-binding protein and CD14 (LPS receptor) and activates expression of inflammatory genes through nuclear factor-kappaB and mitogen-activated protein kinase signaling. A previous case-control study found a modest association of a polymorphism in the TLR4 gene [11381G/C, GG versus GC/CC: odds ratio (OR), 1.26] with risk of prostate cancer. We assessed if sequence variants of TLR4 were associated with the risk of prostate cancer. In a nested case-control design within the Health Professionals Follow-up Study, we identified 700 participants with prostate cancer diagnosed after they had provided a blood specimen in 1993 and before January 2000. Controls were 700 age-matched men without prostate cancer who had had a prostate-specific antigen test after providing a blood specimen. We genotyped 16 common (>5%) single nucleotide polymorphisms (SNP) discovered in a resequencing study spanning TLR4 to test for association between sequence variation in TLR4 and prostate cancer. Homozygosity for the variant alleles of eight SNPs was associated with a statistically significantly lower risk of prostate cancer (TLR4_1893, TLR4_2032, TLR4_2437, TLR4_7764, TLR4_11912, TLR4_16649, TLR4_17050, and TLR4_17923), but the TLR4_15844 polymorphism corresponding to 11381G/C was not associated with prostate cancer (GG versus CG/CC: OR, 1.01; 95% confidence interval, 0.79-1.29). Six common haplotypes (cumulative frequency, 81%) were observed; the global test for association between haplotypes and prostate cancer was statistically significant (chi(2) = 14.8 on 6 degrees of freedom; P = 0.02). Two common haplotypes were statistically significantly associated with altered risk of prostate cancer. Inherited polymorphisms of the innate immune gene TLR4 are associated with risk of prostate cancer.

Sleep Quality and Sleep Patterns in Relation to Consumption of Energy Drinks, Caffeinated Beverages and Other Stimulants among Thai College Students

PubMed Central

Lohsoonthorn, Vitool; Khidir, Hazar; Casillas, Gardenia; Lertmaharit, Somrat; Tadesse, Mahlet G.; Pensuksan, Wipawan C.; Rattananupong, Thanapoom; Gelaye, Bizu; Williams, Michelle A.

2012-01-01

Purpose Poor sleep and heavy use of caffeinated beverages have been implicated as risk factors for a number of adverse health outcomes. Caffeine consumption and use of other stimulants are common among college students globally. However, to our knowledge, no studies have examined the influence of caffeinated beverages on sleep quality of college students in Southeast Asian populations. We conducted this study to evaluate the patterns of sleep quality; and to examine the extent to which poor sleep quality is associated with consumption of energy drinks, caffeinated beverages and other stimulants among 2,854 Thai college students. Methods A questionnaire was administered to ascertain demographic and behavioral characteristics. The Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep habits and quality. Chi-square tests and multivariate logistic regression models were used to identify statistically significant associations. Results Overall, the prevalence of poor sleep quality was found to be 48.1%. A significant percent of students used stimulant beverages (58.0%). Stimulant use (OR 1.50; 95%CI 1.28-1.77) was found to be statistically significant and positively associated with poor sleep quality. Alcohol consumption (OR 3.10; 95% CI 1.72-5.59) and cigarette smoking (OR 1.43; 95% CI 1.02-1.98) also had statistically significant association with increased daytime dysfunction. In conclusion, stimulant use is common among Thai college students and is associated with several indices of poor sleep quality. Conclusion Our findings underscore the need to educate students on the importance of sleep and the influences of dietary and lifestyle choices on their sleep quality and overall health. PMID:23239460

Outlier Removal and the Relation with Reporting Errors and Quality of Psychological Research

PubMed Central

Bakker, Marjan; Wicherts, Jelte M.

2014-01-01

Background The removal of outliers to acquire a significant result is a questionable research practice that appears to be commonly used in psychology. In this study, we investigated whether the removal of outliers in psychology papers is related to weaker evidence (against the null hypothesis of no effect), a higher prevalence of reporting errors, and smaller sample sizes in these papers compared to papers in the same journals that did not report the exclusion of outliers from the analyses. Methods and Findings We retrieved a total of 2667 statistical results of null hypothesis significance tests from 153 articles in main psychology journals, and compared results from articles in which outliers were removed (N = 92) with results from articles that reported no exclusion of outliers (N = 61). We preregistered our hypotheses and methods and analyzed the data at the level of articles. Results show no significant difference between the two types of articles in median p value, sample sizes, or prevalence of all reporting errors, large reporting errors, and reporting errors that concerned the statistical significance. However, we did find a discrepancy between the reported degrees of freedom of t tests and the reported sample size in 41% of articles that did not report removal of any data values. This suggests common failure to report data exclusions (or missingness) in psychological articles. Conclusions We failed to find that the removal of outliers from the analysis in psychological articles was related to weaker evidence (against the null hypothesis of no effect), sample size, or the prevalence of errors. However, our control sample might be contaminated due to nondisclosure of excluded values in articles that did not report exclusion of outliers. Results therefore highlight the importance of more transparent reporting of statistical analyses. PMID:25072606

A comparative study of metal artifacts from common metal orthodontic brackets in magnetic resonance imaging.

PubMed

Dalili Kajan, Zahra; Khademi, Jalil; Alizadeh, Ahmad; Babaei Hemmaty, Yasamin; Atrkar Roushan, Zahra

2015-09-01

This study was performed to compare the metal artifacts from common metal orthodontic brackets in magnetic resonance imaging. A dry mandible with 12 intact premolars was prepared, and was scanned ten times with various types of brackets: American, 3M, Dentaurum, and Masel orthodontic brackets were used, together with either stainless steel (SS) or nickel titanium (NiTi) wires. Subsequently, three different sequences of coronal and axial images were obtained: spin-echo T1 -weighted images, fast spin-echo T2 -weighted images, and fluid-attenuated inversion recovery images. In each sequence, the two sequential axial and coronal images with the largest signal-void area were selected. The largest diameters of the signal voids in the direction of the X-, Y-, and Z-axes were then measured twice. Finally, the mean linear values associated with different orthodontic brackets were analyzed using one-way analysis of variation, and the results were compared using the independent t-test to assess whether the use of SS or NiTi wires had a significant effect on the images. Statistically significant differences were only observed along the Z-axis among the four different brands of orthodontic brackets with SS wires. A statistically significant difference was observed along all axes among the brackets with NiTi wires. A statistically significant difference was found only along the Z-axis between nickel-free and nickel-containing brackets. With respect to all axes, the 3M bracket was associated with smaller signal-void areas. Overall, the 3M and Dentaurum brackets with NiTi wires induced smaller artifacts along all axes than those with SS wires.

A comparative study of metal artifacts from common metal orthodontic brackets in magnetic resonance imaging

PubMed Central

Khademi, Jalil; Alizadeh, Ahmad; Babaei Hemmaty, Yasamin; Atrkar Roushan, Zahra

2015-01-01

Purpose This study was performed to compare the metal artifacts from common metal orthodontic brackets in magnetic resonance imaging. Materials and Methods A dry mandible with 12 intact premolars was prepared, and was scanned ten times with various types of brackets: American, 3M, Dentaurum, and Masel orthodontic brackets were used, together with either stainless steel (SS) or nickel titanium (NiTi) wires. Subsequently, three different sequences of coronal and axial images were obtained: spin-echo T1-weighted images, fast spin-echo T2-weighted images, and fluid-attenuated inversion recovery images. In each sequence, the two sequential axial and coronal images with the largest signal-void area were selected. The largest diameters of the signal voids in the direction of the X-, Y-, and Z-axes were then measured twice. Finally, the mean linear values associated with different orthodontic brackets were analyzed using one-way analysis of variation, and the results were compared using the independent t-test to assess whether the use of SS or NiTi wires had a significant effect on the images. Results Statistically significant differences were only observed along the Z-axis among the four different brands of orthodontic brackets with SS wires. A statistically significant difference was observed along all axes among the brackets with NiTi wires. A statistically significant difference was found only along the Z-axis between nickel-free and nickel-containing brackets. Conclusion With respect to all axes, the 3M bracket was associated with smaller signal-void areas. Overall, the 3M and Dentaurum brackets with NiTi wires induced smaller artifacts along all axes than those with SS wires. PMID:26389058

Accounting for measurement error: a critical but often overlooked process.

PubMed

Harris, Edward F; Smith, Richard N

2009-12-01

Due to instrument imprecision and human inconsistencies, measurements are not free of error. Technical error of measurement (TEM) is the variability encountered between dimensions when the same specimens are measured at multiple sessions. A goal of a data collection regimen is to minimise TEM. The few studies that actually quantify TEM, regardless of discipline, report that it is substantial and can affect results and inferences. This paper reviews some statistical approaches for identifying and controlling TEM. Statistically, TEM is part of the residual ('unexplained') variance in a statistical test, so accounting for TEM, which requires repeated measurements, enhances the chances of finding a statistically significant difference if one exists. The aim of this paper was to review and discuss common statistical designs relating to types of error and statistical approaches to error accountability. This paper addresses issues of landmark location, validity, technical and systematic error, analysis of variance, scaled measures and correlation coefficients in order to guide the reader towards correct identification of true experimental differences. Researchers commonly infer characteristics about populations from comparatively restricted study samples. Most inferences are statistical and, aside from concerns about adequate accounting for known sources of variation with the research design, an important source of variability is measurement error. Variability in locating landmarks that define variables is obvious in odontometrics, cephalometrics and anthropometry, but the same concerns about measurement accuracy and precision extend to all disciplines. With increasing accessibility to computer-assisted methods of data collection, the ease of incorporating repeated measures into statistical designs has improved. Accounting for this technical source of variation increases the chance of finding biologically true differences when they exist.

Quality of reporting statistics in two Indian pharmacology journals.

PubMed

Jaykaran; Yadav, Preeti

2011-04-01

To evaluate the reporting of the statistical methods in articles published in two Indian pharmacology journals. All original articles published since 2002 were downloaded from the journals' (Indian Journal of Pharmacology (IJP) and Indian Journal of Physiology and Pharmacology (IJPP)) website. These articles were evaluated on the basis of appropriateness of descriptive statistics and inferential statistics. Descriptive statistics was evaluated on the basis of reporting of method of description and central tendencies. Inferential statistics was evaluated on the basis of fulfilling of assumption of statistical methods and appropriateness of statistical tests. Values are described as frequencies, percentage, and 95% confidence interval (CI) around the percentages. Inappropriate descriptive statistics was observed in 150 (78.1%, 95% CI 71.7-83.3%) articles. Most common reason for this inappropriate descriptive statistics was use of mean ± SEM at the place of "mean (SD)" or "mean ± SD." Most common statistical method used was one-way ANOVA (58.4%). Information regarding checking of assumption of statistical test was mentioned in only two articles. Inappropriate statistical test was observed in 61 (31.7%, 95% CI 25.6-38.6%) articles. Most common reason for inappropriate statistical test was the use of two group test for three or more groups. Articles published in two Indian pharmacology journals are not devoid of statistical errors.

Survey of editors and reviewers of high-impact psychology journals: statistical and research design problems in submitted manuscripts.

PubMed

Harris, Alex; Reeder, Rachelle; Hyun, Jenny

2011-01-01

The authors surveyed 21 editors and reviewers from major psychology journals to identify and describe the statistical and design errors they encounter most often and to get their advice regarding prevention of these problems. Content analysis of the text responses revealed themes in 3 major areas: (a) problems with research design and reporting (e.g., lack of an a priori power analysis, lack of congruence between research questions and study design/analysis, failure to adequately describe statistical procedures); (b) inappropriate data analysis (e.g., improper use of analysis of variance, too many statistical tests without adjustments, inadequate strategy for addressing missing data); and (c) misinterpretation of results. If researchers attended to these common methodological and analytic issues, the scientific quality of manuscripts submitted to high-impact psychology journals might be significantly improved.

A Comparison of Three Different Methods of Fixation in the Management of Thoracolumbar Fractures.

PubMed

Panteliadis, Pavlos; Musbahi, Omar; Muthian, Senthil; Goyal, Shivam; Montgomery, Alexander Sheriff; Ranganathan, Arun

2017-01-01

Management of thoracolumbar fractures remains controversial in the literature. The primary aims of this study were to assess different levels of fixation with respect to radiological outcomes in terms of fracture reduction and future loss of correction. This is a single center, retrospective study. Fifty-five patients presenting with thoracolumbar fractures between January 2012 and December 2015 were analyzed in the study. The levels of fixation were divided in 3 groups, 1 vertebra above and 1 below the fracture (1/1), 2 above and 2 below (2/2), and 2 above and 1 below (2/1). The most common mechanism was high fall injury and the most common vertebra L1. Burst fractures were the ones with the highest incidence. The 2/2 fixation achieved the best reduction of the fracture but with no statistical significance. The correction is maintained better by the 2/2 fixation but there is no statistical difference compared to the other fixations. Insertion of screws at the fracture level did not improve outcomes. The data of this study identified a trend towards better radiological outcomes for fracture reduction and maintenance of the correction in the 2/2 fixations. However these results are not statistically significant. Future multicenter prospective clinical trials are needed in order to agree on the ideal management and method of fixation for thoracolumbar fractures.

Genome-Wide Association Studies of Anthracnose and Angular Leaf Spot Resistance in Common Bean (Phaseolus vulgaris L.)

PubMed Central

Perseguini, Juliana Morini Küpper Cardoso; Oblessuc, Paula Rodrigues; Rosa, João Ricardo Bachega Feijó; Gomes, Kleber Alves; Chiorato, Alisson Fernando; Carbonell, Sérgio Augusto Morais; Garcia, Antonio Augusto Franco; Vianello, Rosana Pereira; Benchimol-Reis, Luciana Lasry

2016-01-01

The common bean (Phaseolus vulgaris L.) is the world’s most important legume for human consumption. Anthracnose (ANT; Colletotrichum lindemuthianum) and angular leaf spot (ALS; Pseudocercospora griseola) are complex diseases that cause major yield losses in common bean. Depending on the cultivar and environmental conditions, anthracnose and angular leaf spot infections can reduce crop yield drastically. This study aimed to estimate linkage disequilibrium levels and identify quantitative resistance loci (QRL) controlling resistance to both ANT and ALS diseases of 180 accessions of common bean using genome-wide association analysis. A randomized complete block design with four replicates was performed for the ANT and ALS experiments, with four plants per genotype in each replicate. Association mapping analyses were performed for ANT and ALS using a mixed linear model approach implemented in TASSEL. A total of 17 and 11 significant statistically associations involving SSRs were detected for ANT and ALS resistance loci, respectively. Using SNPs, 21 and 17 significant statistically associations were obtained for ANT and angular ALS, respectively, providing more associations with this marker. The SSR-IAC167 and PvM95 markers, both located on chromosome Pv03, and the SNP scaffold00021_89379, were associated with both diseases. The other markers were distributed across the entire common bean genome, with chromosomes Pv03 and Pv08 showing the greatest number of loci associated with ANT resistance. The chromosome Pv04 was the most saturated one, with six markers associated with ALS resistance. The telomeric region of this chromosome showed four markers located between approximately 2.5 Mb and 4.4 Mb. Our results demonstrate the great potential of genome-wide association studies to identify QRLs related to ANT and ALS in common bean. The results indicate a quantitative and complex inheritance pattern for both diseases in common bean. Our findings will contribute to more effective screening of elite germplasm to find resistance alleles for marker-assisted selection in breeding programs. PMID:26930078

Genome-Wide Association Studies of Anthracnose and Angular Leaf Spot Resistance in Common Bean (Phaseolus vulgaris L.).

PubMed

Perseguini, Juliana Morini Küpper Cardoso; Oblessuc, Paula Rodrigues; Rosa, João Ricardo Bachega Feijó; Gomes, Kleber Alves; Chiorato, Alisson Fernando; Carbonell, Sérgio Augusto Morais; Garcia, Antonio Augusto Franco; Vianello, Rosana Pereira; Benchimol-Reis, Luciana Lasry

2016-01-01

The common bean (Phaseolus vulgaris L.) is the world's most important legume for human consumption. Anthracnose (ANT; Colletotrichum lindemuthianum) and angular leaf spot (ALS; Pseudocercospora griseola) are complex diseases that cause major yield losses in common bean. Depending on the cultivar and environmental conditions, anthracnose and angular leaf spot infections can reduce crop yield drastically. This study aimed to estimate linkage disequilibrium levels and identify quantitative resistance loci (QRL) controlling resistance to both ANT and ALS diseases of 180 accessions of common bean using genome-wide association analysis. A randomized complete block design with four replicates was performed for the ANT and ALS experiments, with four plants per genotype in each replicate. Association mapping analyses were performed for ANT and ALS using a mixed linear model approach implemented in TASSEL. A total of 17 and 11 significant statistically associations involving SSRs were detected for ANT and ALS resistance loci, respectively. Using SNPs, 21 and 17 significant statistically associations were obtained for ANT and angular ALS, respectively, providing more associations with this marker. The SSR-IAC167 and PvM95 markers, both located on chromosome Pv03, and the SNP scaffold00021_89379, were associated with both diseases. The other markers were distributed across the entire common bean genome, with chromosomes Pv03 and Pv08 showing the greatest number of loci associated with ANT resistance. The chromosome Pv04 was the most saturated one, with six markers associated with ALS resistance. The telomeric region of this chromosome showed four markers located between approximately 2.5 Mb and 4.4 Mb. Our results demonstrate the great potential of genome-wide association studies to identify QRLs related to ANT and ALS in common bean. The results indicate a quantitative and complex inheritance pattern for both diseases in common bean. Our findings will contribute to more effective screening of elite germplasm to find resistance alleles for marker-assisted selection in breeding programs.

Polymorphisms in the FGF2 gene and risk of serous ovarian cancer: results from the Ovarian Cancer Association Consortium

PubMed Central

Johnatty, Sharon E.; Beesley, Jonathan; Chen, Xiaoqing; Spurdle, Amanda B.; deFazio, Anna; Webb, Penelope M; Goode, Ellen L.; Rider, David N.; Vierkant, Robert A.; Anderson, Stephanie; Wu, Anna H.; Pike, Malcolm; Van Den Berg, David; Moysich, Kirsten; Ness, Roberta; Doherty, Jennifer; Rossing, Mary-Anne; Pearce, Celeste Leigh; Chenevix-Trench, Georgia

2009-01-01

Fibroblast growth factor (FGF)-2 (basic) is a potent angiogenic molecule involved in tumour progression, and is one of several growth factors with a central role in ovarian carcinogenesis. We hypothesised that common single nucleotide polymorphisms (SNPs) in the FGF2 gene may alter angiogenic potential and thereby susceptibility to ovarian cancer. We analysed 25 FGF2 tgSNPs using five independent study populations from the United States and Australia. Analysis was restricted to non-Hispanic White women with serous ovarian carcinoma (1269 cases and 2829 controls). There were no statistically significant associations between any FGF2 SNPs and ovarian cancer risk. There were two nominally statistically significant associations between heterozygosity for two FGF2 SNPs (rs308379 and rs308447; p<0.05) and serous ovarian cancer risk in the combined dataset, but rare homozygous estimates did not achieve statistical significance, nor were they consistent with the log additive model of inheritance. Overall genetic variation in FGF2 does not appear to play a role in susceptibility to ovarian cancer. PMID:19456219

Power-up: A Reanalysis of 'Power Failure' in Neuroscience Using Mixture Modeling

PubMed Central

Wood, John

2017-01-01

Recently, evidence for endemically low statistical power has cast neuroscience findings into doubt. If low statistical power plagues neuroscience, then this reduces confidence in the reported effects. However, if statistical power is not uniformly low, then such blanket mistrust might not be warranted. Here, we provide a different perspective on this issue, analyzing data from an influential study reporting a median power of 21% across 49 meta-analyses (Button et al., 2013). We demonstrate, using Gaussian mixture modeling, that the sample of 730 studies included in that analysis comprises several subcomponents so the use of a single summary statistic is insufficient to characterize the nature of the distribution. We find that statistical power is extremely low for studies included in meta-analyses that reported a null result and that it varies substantially across subfields of neuroscience, with particularly low power in candidate gene association studies. Therefore, whereas power in neuroscience remains a critical issue, the notion that studies are systematically underpowered is not the full story: low power is far from a universal problem. SIGNIFICANCE STATEMENT Recently, researchers across the biomedical and psychological sciences have become concerned with the reliability of results. One marker for reliability is statistical power: the probability of finding a statistically significant result given that the effect exists. Previous evidence suggests that statistical power is low across the field of neuroscience. Our results present a more comprehensive picture of statistical power in neuroscience: on average, studies are indeed underpowered—some very seriously so—but many studies show acceptable or even exemplary statistical power. We show that this heterogeneity in statistical power is common across most subfields in neuroscience. This new, more nuanced picture of statistical power in neuroscience could affect not only scientific understanding, but potentially policy and funding decisions for neuroscience research. PMID:28706080

The prevalence of neurocranium injury in children in Brod-Posavina County.

PubMed

Mihić, Josip; Rotim, Kresimir; Marcikić, Marcel; Smiljanić, Danko; Dikanović, Marinko; Jurjević, Matija; Matić, Ivo

2012-12-01

Head injuries are very common in children and are the most frequent cause of disability and death among children. This retrospective study included 350 children hospitalized for injury of neurocranium over a 5-year period at Dr Josip Bencević General Hospital in Slavonski Brod. Boys were more commonly injured (63.4%) than girls. The most common injuries were recorded in children aged 7-14 (47.1%), followed by those aged 1-6 (33.8%) years. The injuries occurred slightly more often in urban (50.9%) than in rural (46.6%) setting. Children were more commonly injured in the street or on the road (38.6%), followed by injuries sustained at home (35.2%), at school (9.3%) and on playgrounds (5.7%). They were most commonly injured by fall (50%), followed by traffic injuries (33.5%). Statistically significant differences were found in the following age groups: all children younger than one year were injured by fall; children aged 1-14 were mostly injured by fall (less in traffic, and due to hitting), and those aged 15-18 mostly in traffic (less by fall and due to hitting). Children were mostly injured in the street or on the road (in traffic accidents), followed by injuries at home (mostly by fall), at school and around the house or in the yard (mostly by fall); on the playground (due to hitting) and on the road (in traffic accidents) (statistically significant difference). Most of them had head contusion and cerebral commotion combined (46.8%), followed by head contusion alone (12.5%) and skull fractures (10.5%). Hemorrhages and hematomas were rare (epidural, subdural, subarachnoid hemorrhage), found in 3.2% of cases. We hope that our results will prove helpful in planning preventive measures and treatment of injured children.

A close examination of double filtering with fold change and t test in microarray analysis

PubMed Central

2009-01-01

Background Many researchers use the double filtering procedure with fold change and t test to identify differentially expressed genes, in the hope that the double filtering will provide extra confidence in the results. Due to its simplicity, the double filtering procedure has been popular with applied researchers despite the development of more sophisticated methods. Results This paper, for the first time to our knowledge, provides theoretical insight on the drawback of the double filtering procedure. We show that fold change assumes all genes to have a common variance while t statistic assumes gene-specific variances. The two statistics are based on contradicting assumptions. Under the assumption that gene variances arise from a mixture of a common variance and gene-specific variances, we develop the theoretically most powerful likelihood ratio test statistic. We further demonstrate that the posterior inference based on a Bayesian mixture model and the widely used significance analysis of microarrays (SAM) statistic are better approximations to the likelihood ratio test than the double filtering procedure. Conclusion We demonstrate through hypothesis testing theory, simulation studies and real data examples, that well constructed shrinkage testing methods, which can be united under the mixture gene variance assumption, can considerably outperform the double filtering procedure. PMID:19995439

Weighted statistical parameters for irregularly sampled time series

NASA Astrophysics Data System (ADS)

Rimoldini, Lorenzo

2014-01-01

Unevenly spaced time series are common in astronomy because of the day-night cycle, weather conditions, dependence on the source position in the sky, allocated telescope time and corrupt measurements, for example, or inherent to the scanning law of satellites like Hipparcos and the forthcoming Gaia. Irregular sampling often causes clumps of measurements and gaps with no data which can severely disrupt the values of estimators. This paper aims at improving the accuracy of common statistical parameters when linear interpolation (in time or phase) can be considered an acceptable approximation of a deterministic signal. A pragmatic solution is formulated in terms of a simple weighting scheme, adapting to the sampling density and noise level, applicable to large data volumes at minimal computational cost. Tests on time series from the Hipparcos periodic catalogue led to significant improvements in the overall accuracy and precision of the estimators with respect to the unweighted counterparts and those weighted by inverse-squared uncertainties. Automated classification procedures employing statistical parameters weighted by the suggested scheme confirmed the benefits of the improved input attributes. The classification of eclipsing binaries, Mira, RR Lyrae, Delta Cephei and Alpha2 Canum Venaticorum stars employing exclusively weighted descriptive statistics achieved an overall accuracy of 92 per cent, about 6 per cent higher than with unweighted estimators.

Statistics of Low-Mass Companions to Stars: Implications for Their Origin

NASA Technical Reports Server (NTRS)

Stepinski, T. F.; Black, D. C.

2001-01-01

One of the more significant results from observational astronomy over the past few years has been the detection, primarily via radial velocity studies, of low-mass companions (LMCs) to solar-like stars. The commonly held interpretation of these is that the majority are "extrasolar planets" whereas the rest are brown dwarfs, the distinction made on the basis of apparent discontinuity in the distribution of M sin i for LMCs as revealed by a histogram. We report here results from statistical analysis of M sin i, as well as of the orbital elements data for available LMCs, to rest the assertion that the LMCs population is heterogeneous. The outcome is mixed. Solely on the basis of the distribution of M sin i a heterogeneous model is preferable. Overall, we find that a definitive statement asserting that LMCs population is heterogeneous is, at present, unjustified. In addition we compare statistics of LMCs with a comparable sample of stellar binaries. We find a remarkable statistical similarity between these two populations. This similarity coupled with marked populational dissimilarity between LMCs and acknowledged planets motivates us to suggest a common origin hypothesis for LMCs and stellar binaries as an alternative to the prevailing interpretation. We discuss merits of such a hypothesis and indicate a possible scenario for the formation of LMCs.

Limited privacy protection and poor sensitivity: Is it time to move on from the statistical linkage key-581?

PubMed

Randall, Sean M; Ferrante, Anna M; Boyd, James H; Brown, Adrian P; Semmens, James B

2016-08-01

The statistical linkage key (SLK-581) is a common tool for record linkage in Australia, due to its ability to provide some privacy protection. However, newer privacy-preserving approaches may provide greater privacy protection, while allowing high-quality linkage. To evaluate the standard SLK-581, encrypted SLK-581 and a newer privacy-preserving approach using Bloom filters, in terms of both privacy and linkage quality. Linkage quality was compared by conducting linkages on Australian health datasets using these three techniques and examining results. Privacy was compared qualitatively in relation to a series of scenarios where privacy breaches may occur. The Bloom filter technique offered greater privacy protection and linkage quality compared to the SLK-based method commonly used in Australia. The adoption of new privacy-preserving methods would allow both greater confidence in research results, while significantly improving privacy protection. © The Author(s) 2016.

Hearing loss in Behçet syndrome.

PubMed

Bakhshaee, Mehdi; Mahdi, Bakhshaee; Ghasemi, Mohammad Mehdi; Mehdi, Ghasemi Mohammad; Hatef, Mohammad Reza; Reza, Hatef Mohammad; Talebmehr, Mahdieh; Mahdieh, Talebmehr; Shakeri, Mohammad Taghi; Taghi, Shakeri Mohammad

2007-09-01

To determine the prevalence and characteristics of hearing loss in Behçet syndrome. This study included 27 patients with Behçet syndrome and 35 sex-and age-matched controls. A complete audiological evaluation was performed. The average pure-tone audiograms from both groups showed a statistically significant hearing loss in the Behçet group. Sixteen patients (59.26%) showed some degrees of sensorineural hearing loss (SNHL), with the high-frequency type (4, 8, 10, and 12 kHz) being the most common pattern (93.75%). Hearing loss was the fourth most common manifestation. Although the patient's age, sex, and the duration of the disease were not related to hearing loss, there was a significant correlation between a negative pathergy test and hearing loss in patients with Behçet syndrome. We should consider audiovestibular involvement in Behçet syndrome as a common finding.

T-cell responses in oiled guillemots and swans in a rehabilitation setting.

PubMed

Troisi, Gera M

2013-07-01

Aquatic birds are commonly affected by oil spills. Despite rehabilitation efforts, the majority of rehabilitated common guillemots (Uria aalge) do not survive, whereas mute swans (Cygnus olor) tend to have higher postrelease survival. Polyaromatic hydrocarbons (PAHs) present in crude oil and diesel are immunotoxic in birds affecting cell-mediated responses to immunogens. Because it is a target of PAH toxicity, T-lymphocyte response to controlled mitogen administration (phytohemagglutinnin test) was investigated in a scoping study as a potentially useful minimally invasive in vivo test of cell-mediated immunity. The test was performed on 69 mute swans and 31 common guillemots stranded on the Norfolk and Lincolnshire coastline and inland waterways in England (UK) either due to injury or to contamination with crude or diesel oil. T-lymphocyte response was significantly decreased in swans with greater oil scores. T-lymphocyte responses were also decreased in guillemots, but this finding was not statistically significant.

Relationships of French and English Morphophonemic Orthographies to Word Reading, Spelling, and Reading Comprehension during Early and Middle Childhood

ERIC Educational Resources Information Center

Abbott, Robert D.; Fayol, Michel; Zorman, Michel; Casalis, Séverine; Nagy, William; Berninger, Virginia W.

2016-01-01

Two longitudinal studies of word reading, spelling, and reading comprehension identified commonalities and differences in morphophonemic orthographies--French (Study 1, n = 1,313) or English (Study 2, n = 114) in early childhood (Grade 2)and middle childhood (Grade 5). For French and English, statistically significant concurrent relationships…

Summary of School Safety Statistics. National Institute of Justice Report

ERIC Educational Resources Information Center

Carlton, Mary Poulin

2017-01-01

Several high-profile incidents of violence at U.S. schools have, understandably, raised concerns about the safety of students while at school. Just one incident of violence causes significant harm. In light of this, it is important to examine commonly held beliefs about school safety and violence because they sometimes reflect a misperception or…

Results of Propellant Mixing Variable Study Using Precise Pressure-Based Burn Rate Calculations

NASA Technical Reports Server (NTRS)

Stefanski, Philip L.

2014-01-01

A designed experiment was conducted in which three mix processing variables (pre-curative addition mix temperature, pre-curative addition mixing time, and mixer speed) were varied to estimate their effects on within-mix propellant burn rate variability. The chosen discriminator for the experiment was the 2-inch diameter by 4-inch long (2x4) Center-Perforated (CP) ballistic evaluation motor. Motor nozzle throat diameters were sized to produce a common targeted chamber pressure. Initial data analysis did not show a statistically significant effect. Because propellant burn rate must be directly related to chamber pressure, a method was developed that showed statistically significant effects on chamber pressure (either maximum or average) by adjustments to the process settings. Burn rates were calculated from chamber pressures and these were then normalized to a common pressure for comparative purposes. The pressure-based method of burn rate determination showed significant reduction in error when compared to results obtained from the Brooks' modification of the propellant web-bisector burn rate determination method. Analysis of effects using burn rates calculated by the pressure-based method showed a significant correlation of within-mix burn rate dispersion to mixing duration and the quadratic of mixing duration. The findings were confirmed in a series of mixes that examined the effects of mixing time on burn rate variation, which yielded the same results.

How Prevalent Is Object-Based Attention?

PubMed Central

Pilz, Karin S.; Roggeveen, Alexa B.; Creighton, Sarah E.; Bennett, Patrick J.; Sekuler, Allison B.

2012-01-01

Previous research suggests that visual attention can be allocated to locations in space (space-based attention) and to objects (object-based attention). The cueing effects associated with space-based attention tend to be large and are found consistently across experiments. Object-based attention effects, however, are small and found less consistently across experiments. In three experiments we address the possibility that variability in object-based attention effects across studies reflects low incidence of such effects at the level of individual subjects. Experiment 1 measured space-based and object-based cueing effects for horizontal and vertical rectangles in 60 subjects comparing commonly used target detection and discrimination tasks. In Experiment 2 we ran another 120 subjects in a target discrimination task in which rectangle orientation varied between subjects. Using parametric statistical methods, we found object-based effects only for horizontal rectangles. Bootstrapping methods were used to measure effects in individual subjects. Significant space-based cueing effects were found in nearly all subjects in both experiments, across tasks and rectangle orientations. However, only a small number of subjects exhibited significant object-based cueing effects. Experiment 3 measured only object-based attention effects using another common paradigm and again, using bootstrapping, we found only a small number of subjects that exhibited significant object-based cueing effects. Our results show that object-based effects are more prevalent for horizontal rectangles, which is in accordance with the theory that attention may be allocated more easily along the horizontal meridian. The fact that so few individuals exhibit a significant object-based cueing effect presumably is why previous studies of this effect might have yielded inconsistent results. The results from the current study highlight the importance of considering individual subject data in addition to commonly used statistical methods. PMID:22348018

Evaluation of sexual dysfunction in women with type 2 diabetes

PubMed Central

Vafaeimanesh, Jamshid; Raei, Mehdi; Hosseinzadeh, Fatemeh; Parham, Mahmoud

2014-01-01

Background: Sexual dysfunction is a common complication of diabetes that adversely affects their quality of life. Its prevalence is known to be higher in diabetic men with and it is estimated to affect 20-85% of patients but the problem is probably less common in diabetic women. This study investigated the prevalence of sexual dysfunction and its risk factors among women with diabetes. Materials and Methods: This descriptive-analytic study was performed during May 2012 to Feb 2013 at Diabetes clinic of Shahid Beheshti Hospital of Qom and The Female Sexual Function Index (FSFI) was used for evaluation of sexual dysfunction. Conclusion: In this study, 59 (53.6%) women had sexual dysfunction. The mean age of patients with sexual dysfunction and healthy people was 48.22 ± 6.61 and 48.14 ± 5.37 years respectively and it was not statistically different in both groups (P = 0.94). Also, there was no significant difference between two groups in average duration of diabetes, fasting blood sugar (FBS), glycosylated hemoglobin (HbA1c) level, insulin resistance, abdominal circumference and body mass index BMI. Although the history of hypertension, coronary artery disease and exercise levels were not significantly associated with sexual dysfunction, but there was a significant association between albuminuria and sexual dysfunction (P = 0.001). Retinopathy and sexual dysfunction had statistically significant relationship (P = 0.007) while no association was found between diabetic neuropathy and sexual dysfunction (P = 0.79). Results: Sexual dysfunction is a common complication in diabetic patients which accompanies with some complications of diabetes and should be considered especially in patients with nephropathy or retinopathy. PMID:24741512

Cytomorphometric analysis of oral buccal mucosal smears in tobacco and arecanut chewers who abused with and without betel leaf.

PubMed

Noufal, Ahammed; George, Antony; Jose, Maji; Khader, Mohasin Abdul; Jayapalan, Cheriyanthal Sisupalan

2014-01-01

Tobacco in any form (smoking or chewing), arecanut chewing, and alcohol are considered to be the major extrinsic etiological factors for potentially malignant disorders of the oral cavity and for squamous cell carcinoma, the most common oral malignancy in India. An increase in nuclear diameter (ND) and nucleus-cell ratio (NCR) with a reduction in cell diameter (CD) are early cytological indicators of dysplastic change. The authors sought to identify cytomorphometric changes in ND, CD, and NCR of oral buccal cells in tobacco and arecanut chewers who chewed with or without betel leaf. Participants represented 3 groups. Group I consisted of 30 individuals who chewed tobacco and arecanut with betel leaf (BQT chewers). Group II consisted of 30 individuals who chewed tobacco and arecanut without betel leaf (Gutka chewers). Group III comprised 30 apparently healthy nonabusers. Cytological smears were prepared and stained with modified-Papanicolaou stain. Comparisons between Groups I and II and Groups II and III showed that ND was increased, with P values of .054 and .008, respectively, whereas a comparison of Groups I and III showed no statistical significance. Comparisons between Groups I and II and Groups II and III showed that CD was statistically reduced, with P values of .037 and <.000, respectively, whereas comparison of Groups I and III showed no statistical significance. Comparisons between Groups I and II and groups II and III showed that NCR was statistically increased, with P values of <.000, whereas a comparison of Groups I and III showed no statistical significance. CD, ND, and NCR showed statistically significant changes in Group II in comparison with Group I, which could indicate larger and earlier risk of carcinoma for Gutka chewers than in BQT chewers.

Detection and Evaluation of Spatio-Temporal Spike Patterns in Massively Parallel Spike Train Data with SPADE.

PubMed

Quaglio, Pietro; Yegenoglu, Alper; Torre, Emiliano; Endres, Dominik M; Grün, Sonja

2017-01-01

Repeated, precise sequences of spikes are largely considered a signature of activation of cell assemblies. These repeated sequences are commonly known under the name of spatio-temporal patterns (STPs). STPs are hypothesized to play a role in the communication of information in the computational process operated by the cerebral cortex. A variety of statistical methods for the detection of STPs have been developed and applied to electrophysiological recordings, but such methods scale poorly with the current size of available parallel spike train recordings (more than 100 neurons). In this work, we introduce a novel method capable of overcoming the computational and statistical limits of existing analysis techniques in detecting repeating STPs within massively parallel spike trains (MPST). We employ advanced data mining techniques to efficiently extract repeating sequences of spikes from the data. Then, we introduce and compare two alternative approaches to distinguish statistically significant patterns from chance sequences. The first approach uses a measure known as conceptual stability, of which we investigate a computationally cheap approximation for applications to such large data sets. The second approach is based on the evaluation of pattern statistical significance. In particular, we provide an extension to STPs of a method we recently introduced for the evaluation of statistical significance of synchronous spike patterns. The performance of the two approaches is evaluated in terms of computational load and statistical power on a variety of artificial data sets that replicate specific features of experimental data. Both methods provide an effective and robust procedure for detection of STPs in MPST data. The method based on significance evaluation shows the best overall performance, although at a higher computational cost. We name the novel procedure the spatio-temporal Spike PAttern Detection and Evaluation (SPADE) analysis.

Detection and Evaluation of Spatio-Temporal Spike Patterns in Massively Parallel Spike Train Data with SPADE

PubMed Central

Quaglio, Pietro; Yegenoglu, Alper; Torre, Emiliano; Endres, Dominik M.; Grün, Sonja

2017-01-01

Repeated, precise sequences of spikes are largely considered a signature of activation of cell assemblies. These repeated sequences are commonly known under the name of spatio-temporal patterns (STPs). STPs are hypothesized to play a role in the communication of information in the computational process operated by the cerebral cortex. A variety of statistical methods for the detection of STPs have been developed and applied to electrophysiological recordings, but such methods scale poorly with the current size of available parallel spike train recordings (more than 100 neurons). In this work, we introduce a novel method capable of overcoming the computational and statistical limits of existing analysis techniques in detecting repeating STPs within massively parallel spike trains (MPST). We employ advanced data mining techniques to efficiently extract repeating sequences of spikes from the data. Then, we introduce and compare two alternative approaches to distinguish statistically significant patterns from chance sequences. The first approach uses a measure known as conceptual stability, of which we investigate a computationally cheap approximation for applications to such large data sets. The second approach is based on the evaluation of pattern statistical significance. In particular, we provide an extension to STPs of a method we recently introduced for the evaluation of statistical significance of synchronous spike patterns. The performance of the two approaches is evaluated in terms of computational load and statistical power on a variety of artificial data sets that replicate specific features of experimental data. Both methods provide an effective and robust procedure for detection of STPs in MPST data. The method based on significance evaluation shows the best overall performance, although at a higher computational cost. We name the novel procedure the spatio-temporal Spike PAttern Detection and Evaluation (SPADE) analysis. PMID:28596729

Comparison of the effectiveness of some common animal data scaling techniques in estimating human radiation dose

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

Sparks, R.B.; Aydogan, B.

In the development of new radiopharmaceuticals, animal studies are typically performed to get a first approximation of the expected radiation dose in humans. This study evaluates the performance of some commonly used data extrapolation techniques to predict residence times in humans using data collected from animals. Residence times were calculated using animal and human data, and distributions of ratios of the animal results to human results were constructed for each extrapolation method. Four methods using animal data to predict human residence times were examined: (1) using no extrapolation, (2) using relative organ mass extrapolation, (3) using physiological time extrapolation, andmore » (4) using a combination of the mass and time methods. The residence time ratios were found to be log normally distributed for the nonextrapolated and extrapolated data sets. The use of relative organ mass extrapolation yielded no statistically significant change in the geometric mean or variance of the residence time ratios as compared to using no extrapolation. Physiologic time extrapolation yielded a statistically significant improvement (p < 0.01, paired t test) in the geometric mean of the residence time ratio from 0.5 to 0.8. Combining mass and time methods did not significantly improve the results of using time extrapolation alone. 63 refs., 4 figs., 3 tabs.« less

Time series, periodograms, and significance

NASA Astrophysics Data System (ADS)

Hernandez, G.

1999-05-01

The geophysical literature shows a wide and conflicting usage of methods employed to extract meaningful information on coherent oscillations from measurements. This makes it difficult, if not impossible, to relate the findings reported by different authors. Therefore, we have undertaken a critical investigation of the tests and methodology used for determining the presence of statistically significant coherent oscillations in periodograms derived from time series. Statistical significance tests are only valid when performed on the independent frequencies present in a measurement. Both the number of possible independent frequencies in a periodogram and the significance tests are determined by the number of degrees of freedom, which is the number of true independent measurements, present in the time series, rather than the number of sample points in the measurement. The number of degrees of freedom is an intrinsic property of the data, and it must be determined from the serial coherence of the time series. As part of this investigation, a detailed study has been performed which clearly illustrates the deleterious effects that the apparently innocent and commonly used processes of filtering, de-trending, and tapering of data have on periodogram analysis and the consequent difficulties in the interpretation of the statistical significance thus derived. For the sake of clarity, a specific example of actual field measurements containing unevenly-spaced measurements, gaps, etc., as well as synthetic examples, have been used to illustrate the periodogram approach, and pitfalls, leading to the (statistical) significance tests for the presence of coherent oscillations. Among the insights of this investigation are: (1) the concept of a time series being (statistically) band limited by its own serial coherence and thus having a critical sampling rate which defines one of the necessary requirements for the proper statistical design of an experiment; (2) the design of a critical test for the maximum number of significant frequencies which can be used to describe a time series, while retaining intact the variance of the test sample; (3) a demonstration of the unnecessary difficulties that manipulation of the data brings into the statistical significance interpretation of said data; and (4) the resolution and correction of the apparent discrepancy in significance results obtained by the use of the conventional Lomb-Scargle significance test, when compared with the long-standing Schuster-Walker and Fisher tests.

The Effect of Isometric Massage on Global Grip Strength after Conservative Treatment of Distal Radial Fractures. Pilot Study.

PubMed

Ratajczak, Karina; Płomiński, Janusz

2015-01-01

The most common fracture of the distal end of the radius is Colles' fracture. Treatment modalities available for use in hand rehabilitation after injury include massage. The aim of this study was to evaluate the effect of isometric massage on the recovery of hand function in patients with Colles fractures. For this purpose, the strength of the finger flexors was assessed as an objective criterion for the evaluation of hand function. The study involved 40 patients, randomly divided into Group A of 20 patients and Group B of 20 patients. All patients received physical therapy and exercised individually with a physiotherapist. Isometric massage was additionally used in Group A. Global grip strength was assessed using a pneumatic force meter on the first and last day of therapy. Statistical analysis was performed using STATISTICA. Statistical significance was defined as a P value of less than 0.05. In both groups, global grip strength increased significantly after the therapy. There was no statistically significant difference between the groups. The men and women in both groups equally improved grip strength. A statistically significant difference was demonstrated between younger and older patients, with younger patients achieving greater gains in global grip strength in both groups. The incorporation of isometric massage in the rehabilitation plan of patients after a distal radial fracture did not significantly contribute to faster recovery of hand function or improve their quality of life.

Discrimination of common Mediterranean plant species using field spectroradiometry

NASA Astrophysics Data System (ADS)

Manevski, Kiril; Manakos, Ioannis; Petropoulos, George P.; Kalaitzidis, Chariton

2011-12-01

Field spectroradiometry of land surface objects supports remote sensing analysis, facilitates the discrimination of vegetation species, and enhances the mapping efficiency. Especially in the Mediterranean, spectral discrimination of common vegetation types, such as phrygana and maquis species, remains a challenge. Both phrygana and maquis may be used as a direct indicator for grazing management, fire history and severity, and the state of the wider ecosystem equilibrium. This study aims to investigate the capability of field spectroradiometry supporting remote sensing analysis of the land cover of a characteristic Mediterranean area. Five common Mediterranean maquis and phrygana species were examined. Spectra acquisition was performed during an intensive field campaign deployed in spring 2010, supported by a novel platform MUFSPEM@MED (Mobile Unit for Field SPEctral Measurements at the MEDiterranean) for high canopy measurements. Parametric and non-parametric statistical tests have been applied to the continuum-removed reflectance of the species in the visible to shortwave infrared spectral range. Interpretation of the results indicated distinct discrimination between the studied species at specific spectral regions. Statistically significant wavelengths were principally found in both the visible and the near infrared regions of the electromagnetic spectrum. Spectral bands in the shortwave infrared demonstrated significant discrimination features for the examined species adapted to Mediterranean drought. All in all, results confirmed the prospect for a more accurate mapping of the species spatial distribution using remote sensing imagery coupled with in situ spectral information.

The Importance of Statistical Modeling in Data Analysis and Inference

ERIC Educational Resources Information Center

Rollins, Derrick, Sr.

2017-01-01

Statistical inference simply means to draw a conclusion based on information that comes from data. Error bars are the most commonly used tool for data analysis and inference in chemical engineering data studies. This work demonstrates, using common types of data collection studies, the importance of specifying the statistical model for sound…

The prior statistics of object colors.

PubMed

Koenderink, Jan J

2010-02-01

The prior statistics of object colors is of much interest because extensive statistical investigations of reflectance spectra reveal highly non-uniform structure in color space common to several very different databases. This common structure is due to the visual system rather than to the statistics of environmental structure. Analysis involves an investigation of the proper sample space of spectral reflectance factors and of the statistical consequences of the projection of spectral reflectances on the color solid. Even in the case of reflectance statistics that are translationally invariant with respect to the wavelength dimension, the statistics of object colors is highly non-uniform. The qualitative nature of this non-uniformity is due to trichromacy.

Quality of reporting statistics in two Indian pharmacology journals

PubMed Central

Jaykaran; Yadav, Preeti

2011-01-01

Objective: To evaluate the reporting of the statistical methods in articles published in two Indian pharmacology journals. Materials and Methods: All original articles published since 2002 were downloaded from the journals’ (Indian Journal of Pharmacology (IJP) and Indian Journal of Physiology and Pharmacology (IJPP)) website. These articles were evaluated on the basis of appropriateness of descriptive statistics and inferential statistics. Descriptive statistics was evaluated on the basis of reporting of method of description and central tendencies. Inferential statistics was evaluated on the basis of fulfilling of assumption of statistical methods and appropriateness of statistical tests. Values are described as frequencies, percentage, and 95% confidence interval (CI) around the percentages. Results: Inappropriate descriptive statistics was observed in 150 (78.1%, 95% CI 71.7–83.3%) articles. Most common reason for this inappropriate descriptive statistics was use of mean ± SEM at the place of “mean (SD)” or “mean ± SD.” Most common statistical method used was one-way ANOVA (58.4%). Information regarding checking of assumption of statistical test was mentioned in only two articles. Inappropriate statistical test was observed in 61 (31.7%, 95% CI 25.6–38.6%) articles. Most common reason for inappropriate statistical test was the use of two group test for three or more groups. Conclusion: Articles published in two Indian pharmacology journals are not devoid of statistical errors. PMID:21772766

Effects of vibratory stimulation on sexual response in women with spinal cord injury.

PubMed

Sipski, Marca L; Alexander, Craig J; Gomez-Marin, Orlando; Grossbard, Marissa; Rosen, Raymond

2005-01-01

Women with spinal cord injuries (SCIs) have predictable alterations in sexual responses. They commonly have a decreased ability to achieve genital sexual arousal. This study determined whether the use of vibratory stimulation would result in increased genital arousal as measured by vaginal pulse amplitude in women with SCIs. Subjects included 46 women with SCIs and 11 nondisabled control subjects. Results revealed vibratory clitoral stimulation resulted in increased vaginal pulse amplitude as compared with manual clitoral stimulation in both SCI and nondisabled subjects; however, these differences were not statistically significant. Subjective levels of arousal were also compared between SCI and nondisabled control subjects. Both vibratory and manual clitoral stimulation resulted in significantly increased arousal levels in both groups of subjects; however, statistically significant differences between the two conditions were only noted in nondisabled subjects. Further studies of the effects of repetitive vibratory stimulation are underway.

Demodex Species Infestation in Patients with Ear Itching and Its Relationship to Itch Severity.

PubMed

Bilal, Nagihan; Kirişci, Özlem; Özkaya, Esra

2017-06-01

The aim of the present study was to investigate Demodex species infestation in patients with ear itching. The relationship between the severity of ear itching and Demodex spp. positivity has not been previously reported in the literature, and we believe that our study will make a significant contribution to the understanding of the etiology of ear itching. Fifty patients with itching ears and 54 healthy control patients were asked to use a visual analogue scale (VAS) to rate the itch, the itching period, and the medication used for the itching. All samples were evaluated for Demodex spp. under a light microscope. There was no statistically significant difference between the groups in terms of numbers of Demodex spp. (p=0.154), and there was no statistically significant difference between the groups in terms of Demodex spp. positivity (p=0.054). Despite the lack of statistically significant differences, Demodex spp. infestations were more common in the affected group than in the control group. A positive and strongly significant relationship was observed between the number of Demodex spp. and severity of ear itch in the patient group based on VAS scores (p=0.0001; r=0.724). We found that an increased number of Demodex spp. was strongly related to increased severity of ear itching.

A metric to search for relevant words

NASA Astrophysics Data System (ADS)

Zhou, Hongding; Slater, Gary W.

2003-11-01

We propose a new metric to evaluate and rank the relevance of words in a text. The method uses the density fluctuations of a word to compute an index that measures its degree of clustering. Highly significant words tend to form clusters, while common words are essentially uniformly spread in a text. If a word is not rare, the metric is stable when we move any individual occurrence of this word in the text. Furthermore, we prove that the metric always increases when words are moved to form larger clusters, or when several independent documents are merged. Using the Holy Bible as an example, we show that our approach reduces the significance of common words when compared to a recently proposed statistical metric.

On use of the multistage dose-response model for assessing laboratory animal carcinogenicity

PubMed Central

Nitcheva, Daniella; Piegorsch, Walter W.; West, R. Webster

2007-01-01

We explore how well a statistical multistage model describes dose-response patterns in laboratory animal carcinogenicity experiments from a large database of quantal response data. The data are collected from the U.S. EPA’s publicly available IRIS data warehouse and examined statistically to determine how often higher-order values in the multistage predictor yield significant improvements in explanatory power over lower-order values. Our results suggest that the addition of a second-order parameter to the model only improves the fit about 20% of the time, while adding even higher-order terms apparently does not contribute to the fit at all, at least with the study designs we captured in the IRIS database. Also included is an examination of statistical tests for assessing significance of higher-order terms in a multistage dose-response model. It is noted that bootstrap testing methodology appears to offer greater stability for performing the hypothesis tests than a more-common, but possibly unstable, “Wald” test. PMID:17490794

Spatial Autocorrelation of Cancer Incidence in Saudi Arabia

PubMed Central

Al-Ahmadi, Khalid; Al-Zahrani, Ali

2013-01-01

Little is known about the geographic distribution of common cancers in Saudi Arabia. We explored the spatial incidence patterns of common cancers in Saudi Arabia using spatial autocorrelation analyses, employing the global Moran’s I and Anselin’s local Moran’s I statistics to detect nonrandom incidence patterns. Global ordinary least squares (OLS) regression and local geographically-weighted regression (GWR) were applied to examine the spatial correlation of cancer incidences at the city level. Population-based records of cancers diagnosed between 1998 and 2004 were used. Male lung cancer and female breast cancer exhibited positive statistically significant global Moran’s I index values, indicating a tendency toward clustering. The Anselin’s local Moran’s I analyses revealed small significant clusters of lung cancer, prostate cancer and Hodgkin’s disease among males in the Eastern region and significant clusters of thyroid cancers in females in the Eastern and Riyadh regions. Additionally, both regression methods found significant associations among various cancers. For example, OLS and GWR revealed significant spatial associations among NHL, leukemia and Hodgkin’s disease (r² = 0.49–0.67 using OLS and r² = 0.52–0.68 using GWR) and between breast and prostate cancer (r² = 0.53 OLS and 0.57 GWR) in Saudi Arabian cities. These findings may help to generate etiologic hypotheses of cancer causation and identify spatial anomalies in cancer incidence in Saudi Arabia. Our findings should stimulate further research on the possible causes underlying these clusters and associations. PMID:24351742

Research design and statistical methods in Pakistan Journal of Medical Sciences (PJMS).

PubMed

Akhtar, Sohail; Shah, Syed Wadood Ali; Rafiq, M; Khan, Ajmal

2016-01-01

This article compares the study design and statistical methods used in 2005, 2010 and 2015 of Pakistan Journal of Medical Sciences (PJMS). Only original articles of PJMS were considered for the analysis. The articles were carefully reviewed for statistical methods and designs, and then recorded accordingly. The frequency of each statistical method and research design was estimated and compared with previous years. A total of 429 articles were evaluated (n=74 in 2005, n=179 in 2010, n=176 in 2015) in which 171 (40%) were cross-sectional and 116 (27%) were prospective study designs. A verity of statistical methods were found in the analysis. The most frequent methods include: descriptive statistics (n=315, 73.4%), chi-square/Fisher's exact tests (n=205, 47.8%) and student t-test (n=186, 43.4%). There was a significant increase in the use of statistical methods over time period: t-test, chi-square/Fisher's exact test, logistic regression, epidemiological statistics, and non-parametric tests. This study shows that a diverse variety of statistical methods have been used in the research articles of PJMS and frequency improved from 2005 to 2015. However, descriptive statistics was the most frequent method of statistical analysis in the published articles while cross-sectional study design was common study design.

Personality Traits and Common Psychiatric Conditions in Adult Patients with Acne Vulgaris

PubMed Central

Çölgeçen, Emine

2015-01-01

Background We believe that instances of neuroticism and common psychiatric disorders are higher in adults with acne vulgaris than the normal population. Objective Instances of acne in adults have been increasing in frequency in recent years. The aim of this study was to investigate personality traits and common psychiatric conditions in patients with adult acne vulgaris. Methods Patients who visited the dermatology outpatient clinic at Bozok University Medical School with a complaint of acne and who volunteered for this study were included. The Symptom Checklist 90-Revised (SCL 90-R) Global Symptom Index (GSI), somatization, depression, and anxiety subscales and the Eysenck Personality Questionnaire-Revised Short Form (EPQ-RSF) were administered to 40 patients who fulfilled the inclusion criteria before treatment. The results were compared with those of a control group. Results Of the 40 patients included in this study, 34 were female and 6 were male. The GSI and the somatization, depression, and anxiety subscales of the SCL 90-R were evaluated. Patients with adult acne had statistically significant higher scores than the control group on all of these subscales. In addition, patients with adult acne had statistically significantly higher scores on the neuroticism subscale of the EPQ-RSF. Conclusion Our results show that common psychiatric conditions are frequent in adult patients with acne. More importantly, neurotic personality characteristics are observed more frequently in these patients. These findings suggest that acne in adults is a disorder that has both medical and psychosomatic characteristics and requires a multi-disciplinary approach. PMID:25673931

Are edible insects more or less 'healthy' than commonly consumed meats? A comparison using two nutrient profiling models developed to combat over- and undernutrition.

PubMed

Payne, C L R; Scarborough, P; Rayner, M; Nonaka, K

2016-03-01

Insects have been the subject of recent attention as a potentially environmentally sustainable and nutritious alternative to traditional protein sources. The purpose of this paper is to test the hypothesis that insects are nutritionally preferable to meat, using two evaluative tools that are designed to combat over- and under-nutrition. We selected 183 datalines of publicly available data on the nutrient composition of raw cuts and offal of three commonly consumed meats (beef, pork and chicken), and six commercially available insect species, for energy and 12 relevant nutrients. We applied two nutrient profiling tools to this data: The Ofcom model, which is used in the United Kingdom, and the Nutrient Value Score (NVS), which has been used in East Africa. We compared the median nutrient profile scores of different insect species and meat types using non-parametric tests and applied Bonferroni adjustments to assess for statistical significance in differences. Insect nutritional composition showed high diversity between species. According to the Ofcom model, no insects were significantly 'healthier' than meat products. The NVS assigned crickets, palm weevil larvae and mealworm a significantly healthier score than beef (P<0.001) and chicken (P<0.001). No insects were statistically less healthy than meat. Insect nutritional composition is highly diverse in comparison with commonly consumed meats. The food category 'insects' contains some foods that could potentially exacerbate diet-related public health problems related to over-nutrition, but may be effective in combating under-nutrition.

Proinflammatory cytokine levels in patients with conversion disorder.

PubMed

Tiyekli, Utkan; Calıyurt, Okan; Tiyekli, Nimet Dilek

2013-06-01

It was aimed to evaluate the relationship between proinflammatory cytokine levels and conversion disorder both commonly known as stress regulated. Baseline proinflammatory cytokine levels-[Tumour necrosis factor alpha (TNF-α), Interleukin-1 beta (IL-1β), Interleukin-6 (IL-6)]-were evaluated with enzyme-linked immunosorbent assay in 35 conversion disorder patients and 30 healthy controls. Possible changes in proinflammatory cytokine levels were evaluated again, after their acute phase in conversion disorder patients. Statistically significant decreased serum TNF-α levels were obtained in acute phase of conversion disorder. Those levels increased after acute conversion phase. There were no statistically significant difference observed between groups in serum IL-1β and (IL-6) levels. Stress associated with conversion disorder may suppress immune function in acute conversion phase and may have diagnostic and therapeutic value.

Two-Year Trends of Taxane-Induced Neuropathy in Women Enrolled in a Randomized Trial of Acetyl-L-Carnitine (SWOG S0715).

PubMed

Hershman, Dawn L; Unger, Joseph M; Crew, Katherine D; Till, Cathee; Greenlee, Heather; Minasian, Lori M; Moinpour, Carol M; Lew, Danika L; Fehrenbacher, Louis; Wade, James L; Wong, Siu-Fun; Fisch, Michael J; Lynn Henry, N; Albain, Kathy S

2018-06-01

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and disabling side effect of taxanes. Acetyl-L-carnitine (ALC) was unexpectedly found to increase CIPN in a randomized trial. We investigated the long-term patterns of CIPN among patients in this trial. S0715 was a randomized, double-blind, multicenter trial comparing ALC (1000 mg three times a day) with placebo for 24 weeks in women undergoing adjuvant taxane-based chemotherapy for breast cancer. CIPN was measured by the 11-item neurotoxicity (NTX) component of the FACT-Taxane scale at weeks 12, 24, 36, 52, and 104. We examined NTX scores over two years using linear mixed models for longitudinal data. Individual time points were examined using linear regression. Regression analyses included stratification factors and the baseline score as covariates. All statistical tests were two-sided. Four-hundred nine subjects were eligible for evaluation. Patients receiving ALC had a statistically significantly (P = .01) greater reduction in NTX scores (worse CIPN) of -1.39 points (95% confidence interval [CI] = -2.48 to -0.30) than the placebo group. These differences were particularly evident at weeks 24 (-1.68, 95% CI = -3.02 to -0.33), 36 (-1.37, 95% CI = -2.69 to -0.04), and 52 (-1.83, 95% CI = -3.35 to -0.32). At 104 weeks, 39.5% on the ALC arm and 34.4% on the placebo arm reported a five-point (10%) decrease from baseline. For both treatment groups, 104-week NTX scores were statistically significantly different compared with baseline (P < .001). For both groups, NTX scores were reduced from baseline and remained persistently low. Twenty-four weeks of ALC therapy resulted in statistically significantly worse CIPN over two years. Understanding the mechanism of this persistent effect may inform prevention and treatment strategies. Until then, the potential efficacy and harms of commonly used supplements should be rigorously studied.

The chi-square test of independence.

PubMed

McHugh, Mary L

2013-01-01

The Chi-square statistic is a non-parametric (distribution free) tool designed to analyze group differences when the dependent variable is measured at a nominal level. Like all non-parametric statistics, the Chi-square is robust with respect to the distribution of the data. Specifically, it does not require equality of variances among the study groups or homoscedasticity in the data. It permits evaluation of both dichotomous independent variables, and of multiple group studies. Unlike many other non-parametric and some parametric statistics, the calculations needed to compute the Chi-square provide considerable information about how each of the groups performed in the study. This richness of detail allows the researcher to understand the results and thus to derive more detailed information from this statistic than from many others. The Chi-square is a significance statistic, and should be followed with a strength statistic. The Cramer's V is the most common strength test used to test the data when a significant Chi-square result has been obtained. Advantages of the Chi-square include its robustness with respect to distribution of the data, its ease of computation, the detailed information that can be derived from the test, its use in studies for which parametric assumptions cannot be met, and its flexibility in handling data from both two group and multiple group studies. Limitations include its sample size requirements, difficulty of interpretation when there are large numbers of categories (20 or more) in the independent or dependent variables, and tendency of the Cramer's V to produce relative low correlation measures, even for highly significant results.

Impaired Statistical Learning in Developmental Dyslexia

PubMed Central

Thiessen, Erik D.; Holt, Lori L.

2015-01-01

Purpose Developmental dyslexia (DD) is commonly thought to arise from phonological impairments. However, an emerging perspective is that a more general procedural learning deficit, not specific to phonological processing, may underlie DD. The current study examined if individuals with DD are capable of extracting statistical regularities across sequences of passively experienced speech and nonspeech sounds. Such statistical learning is believed to be domain-general, to draw upon procedural learning systems, and to relate to language outcomes. Method DD and control groups were familiarized with a continuous stream of syllables or sine-wave tones, the ordering of which was defined by high or low transitional probabilities across adjacent stimulus pairs. Participants subsequently judged two 3-stimulus test items with either high or low statistical coherence as being the most similar to the sounds heard during familiarization. Results As with control participants, the DD group was sensitive to the transitional probability structure of the familiarization materials as evidenced by above-chance performance. However, the performance of participants with DD was significantly poorer than controls across linguistic and nonlinguistic stimuli. In addition, reading-related measures were significantly correlated with statistical learning performance of both speech and nonspeech material. Conclusion Results are discussed in light of procedural learning impairments among participants with DD. PMID:25860795

Polymorphism 4G/5G of the plasminogen activator inhibitor 1 gene as a risk factor for the development of allergic rhinitis symptoms in patients with asthma.

PubMed

Lampalo, Marina; Jukic, Irena; Bingulac-Popovic, Jasna; Marunica, Ivona; Petlevski, Roberta; Pavlisa, Gordana; Popovic-Grle, Sanja

2017-06-01

Plasminogen activator inhibitor-1 (PAI-1) is a glycoprotein which has a role in tissue remodelling after inflammatory processes. The objective is to investigate the frequency of PAI-1 gene polymorphism (4G/5G) in patients with a lung ventilation dysfunction in asthma and allergic rhinitis. Genomic DNA was isolated and genotypes of polymorphism of PAI-1 4G/5G and ABO were determined using the methods of RT-PCR and PCR-SSP. Study group includes 145 adult patients diagnosed with chronic asthma, with all clinically relevant parameters and the laboratory markers of pO 2 , IgE and eosinophils in sputum and nasal swab. In the processing of data, appropriate statistical tests (Kolmogorov-Smirnov test, median, interquartile ranges, χ 2 and Mann-Whitney U tests) were used. Patients with symptoms of allergic rhinitis were significantly younger and had an almost four time higher levels of IgE (P = 0.001), higher pO 2 (P = 0.002) and PEF (P = 0.036), compared to those who do not have these symptoms. Genotype PAI 4G/4G is significantly more common in patients with allergic rhinitis (28.1% vs. 16.1%; P = 0.017) compared to the genotype 5G/5G. Carriers of the genotype 4G/5G also have a borderline statistical significance. There were no statistically significant difference in the incidence of allergic rhinitis in the carriers of any ABO genotypes. The frequency of PAI genotype 4G/4G is significantly more common in patients with allergic rhinitis. The results suggest that the carriers of at least one 4G allele are at a higher risk for developing symptoms of allergic rhinitis in asthma.

EEG-LORETA endophenotypes of the common idiopathic generalized epilepsy syndromes.

PubMed

Clemens, B; Puskás, S; Besenyei, M; Emri, M; Opposits, G; Kis, S A; Hollódy, K; Fogarasi, A; Kondákor, I; Füle, K; Bense, K; Fekete, I

2012-05-01

We tested the hypothesis that the cortical areas with abnormal local EEG synchronization are dissimilar in the three common idiopathic generalized epilepsy (IGE) phenotypes: IGE patients with absence seizures (ABS), juvenile myoclonic epilepsy (JME) and epilepsy with generalized tonic-clonic seizures exclusively (EGTCS). Groups of unmedicated ABS, JME and EGTCS patients were investigated. Waking EEG background activity (without any epileptiform potentials) was analyzed by a source localization method, LORETA (Low Resolution Electromagnetic Tomography). Each patient group was compared to a separate, age-matched group of healthy control persons. Voxel-based, normalized broad-band (delta, theta, alpha, and beta) and very narrow band (VNB, 1Hz bandwidth, from 1 to 25Hz) LORETA activity (=current source density, A/m(2)) were computed for each person. Group comparison included subtraction (average patient data minus average control data) and group statistics (multiple t-tests, where Bonferroni-corrected p<0.05 values were accepted as statistically significant). Statistically not significant main findings were: overall increased delta and theta broad band activity in the ABS and JME groups; decrease of alpha and beta activity in the EGTCS group. Statistically significant main findings were as follows. JME group: bilaterally increased theta activity in posterior (temporal, parietal, and occipital) cortical areas; bilaterally increased activity in the medial and basal prefrontal area in the 8Hz VNB; bilaterally decreased activity in the precuneus, posterior cingulate and superior parietal lobule in the 11Hz and 21-22Hz VNBs. ABS group: bilaterally increased theta activity emerged in the basal prefrontal and medial temporal limbic areas. Decreased activity was found at 19-21Hz in the right postcentral gyrus and parts of the right superior and medial temporal gyri. EGTCS group: decreased activity was found in the frontal cortex and the postcentral gyrus at 10-11Hz, increased activity in the right parahippocampal gyrus at 16-18Hz. Increased theta activity in the posterior parts of the cortex is the endophenotype for JME. Increased theta activity in the fronto-temporal limbic areas is the endophenotype for ABS. Statistically not significant findings might indicate diffuse biochemical abnormality of the cortex in JME and ABS. EEG-LORETA endophenotypes may correspond to the selective propensity to generate absence and myoclonic seizures in the ABS and JME syndromes. Copyright © 2011 Elsevier B.V. All rights reserved.

Evaluation of Safety and Patient Subjective Efficacy of Using Radiofrequency and Pulsed Magnetic Fields for the Treatment of Striae (Stretch Marks)

PubMed Central

Dover, Jeffrey S.; Rothaus, Kenneth

2014-01-01

Stretch marks are common skin disorders that are dermal scars with associated epidermal atrophy. They are of significant concern or psychological concern to many. This manuscript describes the use of multipolar radiofrequency with pulsed magnetic fields that was successfully used to diminish these lesions in 16 subjects undergoing a series of treatments. The improvements noted were statistically significant and no serious adverse events were noted. PMID:25276274

Statistical analysis of co-occurrence patterns in microbial presence-absence datasets

PubMed Central

Bewick, Sharon; Thielen, Peter; Mehoke, Thomas; Breitwieser, Florian P.; Paudel, Shishir; Adhikari, Arjun; Wolfe, Joshua; Slud, Eric V.; Karig, David; Fagan, William F.

2017-01-01

Drawing on a long history in macroecology, correlation analysis of microbiome datasets is becoming a common practice for identifying relationships or shared ecological niches among bacterial taxa. However, many of the statistical issues that plague such analyses in macroscale communities remain unresolved for microbial communities. Here, we discuss problems in the analysis of microbial species correlations based on presence-absence data. We focus on presence-absence data because this information is more readily obtainable from sequencing studies, especially for whole-genome sequencing, where abundance estimation is still in its infancy. First, we show how Pearson’s correlation coefficient (r) and Jaccard’s index (J)–two of the most common metrics for correlation analysis of presence-absence data–can contradict each other when applied to a typical microbiome dataset. In our dataset, for example, 14% of species-pairs predicted to be significantly correlated by r were not predicted to be significantly correlated using J, while 37.4% of species-pairs predicted to be significantly correlated by J were not predicted to be significantly correlated using r. Mismatch was particularly common among species-pairs with at least one rare species (<10% prevalence), explaining why r and J might differ more strongly in microbiome datasets, where there are large numbers of rare taxa. Indeed 74% of all species-pairs in our study had at least one rare species. Next, we show how Pearson’s correlation coefficient can result in artificial inflation of positive taxon relationships and how this is a particular problem for microbiome studies. We then illustrate how Jaccard’s index of similarity (J) can yield improvements over Pearson’s correlation coefficient. However, the standard null model for Jaccard’s index is flawed, and thus introduces its own set of spurious conclusions. We thus identify a better null model based on a hypergeometric distribution, which appropriately corrects for species prevalence. This model is available from recent statistics literature, and can be used for evaluating the significance of any value of an empirically observed Jaccard’s index. The resulting simple, yet effective method for handling correlation analysis of microbial presence-absence datasets provides a robust means of testing and finding relationships and/or shared environmental responses among microbial taxa. PMID:29145425

Prevalence of dental anomalies in Saudi orthodontic patients.

PubMed

Al-Jabaa, Aljazi H; Aldrees, Abdullah M

2013-07-01

This study aimed to investigate the prevalence of dental anomalies and study the association of these anomalies with different types of malocclusion in a random sample of Saudi orthodontic patients. Six hundred and two randomly selected pretreatment records including orthopantomographs (OPG), and study models were evaluated. The molar relationship was determined using pretreatment study models, and OPG were examined to investigate the prevalence of dental anomalies among the sample. The most common types of the investigated anomalies were: impaction followed by hypodontia, microdontia, macrodontia, ectopic eruption and supernumerary. No statistical significant correlations were observed between sex and dental anomalies. Dental anomalies were more commonly found in class I followed by asymmetric molar relation, then class II and finally class III molar relation. No malocclusion group had a statistically significant relation with any individual dental anomaly. The prevalence of dental anomalies among Saudi orthodontic patients was higher than the general population. Although, orthodontic patients have been reported to have high rates of dental anomalies, orthodontists often fail to consider this. If not detected, dental anomalies can complicate dental and orthodontic treatment; therefore, their presence should be carefully investigated during orthodontic diagnosis and considered during treatment planning.

Substance Use as a Strong Predictor of Poor Academic Achievement among University Students

PubMed Central

Fekadu, Wubalem; Mekonnen, Tefera Chane; Workie, Shimelash Bitew

2017-01-01

Background Substance use is a growing concern globally and its association with students' academic performance is not well studied. Objective This study was aimed to assess the prevalence of substance use (alcohol, tobacco, and khat) and its association with academic performance among university students. Methods Cross-sectional study was conducted among Wolaita Sodo University students. A total of 747 students were selected by using cluster sampling technique. Data were collected by pretested self-administered questionnaire and examined using descriptive statistics and linear regression with 95% confidence intervals. Variables with p value of less than 0.05 were considered as statistically significant. Result Prevalence of substance use (alcohol, tobacco, and khat) was 28.6%. Substance use (current smoking, chewing khat at least weekly, drinking alcohol on a daily basis, and having intimate friend who uses substance) was significantly and negatively associated with students' academic performance. Conclusion Substance use among Wolaita Sodo University students was as common as other studies in Sub-Saharan countries and negatively associated with students' academic achievement. The common practice of substance use and its association with poor academic performance demand the universities to have a good control of substance and to implement youth friendly activities. PMID:28680879

Vaginal douching practice: Frequency, associated factors and relationship with vulvovaginal symptoms.

PubMed

Yanikkerem, Emre; Yasayan, Aysegul

2016-04-01

To determine the frequency, associated factors and relationship with vulvovaginal symptoms and vaginal douching among Turkish women. The cross-sectional, analytical study was conducted at Merkez Efendi Hospital, Manisa, Turkey, from January to June 2014 using a questionnaire. Statistical analysis was carried out using SPSS 17. Of the total 343 women in the study, 91(26.5%) had reported vaginal douching in the preceding year. Statistically significant relationship was determined between the vaginal douching behaviour and couples who had low educationand low income levels, having unplanned pregnancy and had someone in their neighbourhood who douched (p< 0.05 each). The most common reason for using vaginal douching was reported to be cleanliness by 85(93.4%) women, prevention of genital infections 75(82.4%), cleaning after/before sexual intercourse 72(79%), during menstruation 49(54%), prevention of vaginal discharge 69(76%), decreasing of unpleasant odours 65(71.4%) and religious beliefs 46(50.5%). Self-reported history of vaginal infection was significantly more common for women who douched compared those who did not (p< 0.05). Healthcare providers should determine the reason and risky groups of women and educate the women to stop the vaginal douching behaviour and harmful effects of vaginal douching.

Invited Commentary: The Need for Cognitive Science in Methodology.

PubMed

Greenland, Sander

2017-09-15

There is no complete solution for the problem of abuse of statistics, but methodological training needs to cover cognitive biases and other psychosocial factors affecting inferences. The present paper discusses 3 common cognitive distortions: 1) dichotomania, the compulsion to perceive quantities as dichotomous even when dichotomization is unnecessary and misleading, as in inferences based on whether a P value is "statistically significant"; 2) nullism, the tendency to privilege the hypothesis of no difference or no effect when there is no scientific basis for doing so, as when testing only the null hypothesis; and 3) statistical reification, treating hypothetical data distributions and statistical models as if they reflect known physical laws rather than speculative assumptions for thought experiments. As commonly misused, null-hypothesis significance testing combines these cognitive problems to produce highly distorted interpretation and reporting of study results. Interval estimation has so far proven to be an inadequate solution because it involves dichotomization, an avenue for nullism. Sensitivity and bias analyses have been proposed to address reproducibility problems (Am J Epidemiol. 2017;186(6):646-647); these methods can indeed address reification, but they can also introduce new distortions via misleading specifications for bias parameters. P values can be reframed to lessen distortions by presenting them without reference to a cutoff, providing them for relevant alternatives to the null, and recognizing their dependence on all assumptions used in their computation; they nonetheless require rescaling for measuring evidence. I conclude that methodological development and training should go beyond coverage of mechanistic biases (e.g., confounding, selection bias, measurement error) to cover distortions of conclusions produced by statistical methods and psychosocial forces. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Statistics used in current nursing research.

PubMed

Zellner, Kathleen; Boerst, Connie J; Tabb, Wil

2007-02-01

Undergraduate nursing research courses should emphasize the statistics most commonly used in the nursing literature to strengthen students' and beginning researchers' understanding of them. To determine the most commonly used statistics, we reviewed all quantitative research articles published in 13 nursing journals in 2000. The findings supported Beitz's categorization of kinds of statistics. Ten primary statistics used in 80% of nursing research published in 2000 were identified. We recommend that the appropriate use of those top 10 statistics be emphasized in undergraduate nursing education and that the nursing profession continue to advocate for the use of methods (e.g., power analysis, odds ratio) that may contribute to the advancement of nursing research.

Observations on Three Endpoint Properties and Their Relationship to Regulatory Outcomes of European Oncology Marketing Applications

PubMed Central

Stolk, Pieter; McAuslane, James Neil; Schellens, Jan; Breckenridge, Alasdair M.; Leufkens, Hubert

2015-01-01

Background. Guidance and exploratory evidence indicate that the type of endpoints and the magnitude of their outcome can define a therapy’s clinical activity; however, little empirical evidence relates specific endpoint properties with regulatory outcomes. Materials and Methods. We explored the relationship of 3 endpoint properties to regulatory outcomes by assessing 50 oncology marketing authorization applications (MAAs; reviewed from 2009 to 2013). Results. Overall, 16 (32%) had a negative outcome. The most commonly used hard endpoints were overall survival (OS) and the duration of response or stable disease. OS was a component of 91% approved and 63% failed MAAs. The most commonly used surrogate endpoints were progression-free survival (PFS), response rate, and health-related quality of life assessments. There was no difference (p = .3801) between the approved and failed MAA cohorts in the proportion of hard endpoints used. A mean of slightly more than four surrogate endpoints were used per approved MAA compared with slightly more than two for failed MAAs. Longer OS and PFS duration outcomes were generally associated with approvals, often when not statistically significant. The approved cohort was associated with a preponderance of statistically significant (p < .05) improvements in primary endpoints (p < .0001 difference between the approved and failed groups). Conclusion. Three key endpoint properties (type of endpoint [hard/surrogate], magnitude of an endpoint outcome, and its statistical significance) are consistent with the European Medicines Agency guidance and, notwithstanding the contribution of unique disease-specific circumstances, are associated with a predictable positive outcome for oncology MAAs. Implications for Practice: Regulatory decisions made by the European Medicines Agency determine which new medicines will be available to European prescribers and for which therapeutic indications. Regulatory success or failure can be influenced by many factors. This study assessed three key properties of endpoints used in preauthorization trials (type of endpoint [hard/surrogate], magnitude of endpoint outcome, and its statistical significance) and whether they are associated with a positive regulatory outcome. Clinicians can use these properties, which are described in the publicly available European public assessment reports, to help guide their understanding of the clinical effect of new oncologic therapies. PMID:25948678

Observations on Three Endpoint Properties and Their Relationship to Regulatory Outcomes of European Oncology Marketing Applications.

PubMed

Liberti, Lawrence; Stolk, Pieter; McAuslane, James Neil; Schellens, Jan; Breckenridge, Alasdair M; Leufkens, Hubert

2015-06-01

Guidance and exploratory evidence indicate that the type of endpoints and the magnitude of their outcome can define a therapy's clinical activity; however, little empirical evidence relates specific endpoint properties with regulatory outcomes. We explored the relationship of 3 endpoint properties to regulatory outcomes by assessing 50 oncology marketing authorization applications (MAAs; reviewed from 2009 to 2013). Overall, 16 (32%) had a negative outcome. The most commonly used hard endpoints were overall survival (OS) and the duration of response or stable disease. OS was a component of 91% approved and 63% failed MAAs. The most commonly used surrogate endpoints were progression-free survival (PFS), response rate, and health-related quality of life assessments. There was no difference (p = .3801) between the approved and failed MAA cohorts in the proportion of hard endpoints used. A mean of slightly more than four surrogate endpoints were used per approved MAA compared with slightly more than two for failed MAAs. Longer OS and PFS duration outcomes were generally associated with approvals, often when not statistically significant. The approved cohort was associated with a preponderance of statistically significant (p < .05) improvements in primary endpoints (p < .0001 difference between the approved and failed groups). Three key endpoint properties (type of endpoint [hard/surrogate], magnitude of an endpoint outcome, and its statistical significance) are consistent with the European Medicines Agency guidance and, notwithstanding the contribution of unique disease-specific circumstances, are associated with a predictable positive outcome for oncology MAAs. Regulatory decisions made by the European Medicines Agency determine which new medicines will be available to European prescribers and for which therapeutic indications. Regulatory success or failure can be influenced by many factors. This study assessed three key properties of endpoints used in preauthorization trials (type of endpoint [hard/surrogate], magnitude of endpoint outcome, and its statistical significance) and whether they are associated with a positive regulatory outcome. Clinicians can use these properties, which are described in the publicly available European public assessment reports, to help guide their understanding of the clinical effect of new oncologic therapies. ©AlphaMed Press.

Searching for molecular markers in head and neck squamous cell carcinomas (HNSCC) by statistical and bioinformatic analysis of larynx-derived SAGE libraries

PubMed Central

Silveira, Nelson JF; Varuzza, Leonardo; Machado-Lima, Ariane; Lauretto, Marcelo S; Pinheiro, Daniel G; Rodrigues, Rodrigo V; Severino, Patrícia; Nobrega, Francisco G; Silva, Wilson A; de B Pereira, Carlos A; Tajara, Eloiza H

2008-01-01

Background Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies in humans. The average 5-year survival rate is one of the lowest among aggressive cancers, showing no significant improvement in recent years. When detected early, HNSCC has a good prognosis, but most patients present metastatic disease at the time of diagnosis, which significantly reduces survival rate. Despite extensive research, no molecular markers are currently available for diagnostic or prognostic purposes. Methods Aiming to identify differentially-expressed genes involved in laryngeal squamous cell carcinoma (LSCC) development and progression, we generated individual Serial Analysis of Gene Expression (SAGE) libraries from a metastatic and non-metastatic larynx carcinoma, as well as from a normal larynx mucosa sample. Approximately 54,000 unique tags were sequenced in three libraries. Results Statistical data analysis identified a subset of 1,216 differentially expressed tags between tumor and normal libraries, and 894 differentially expressed tags between metastatic and non-metastatic carcinomas. Three genes displaying differential regulation, one down-regulated (KRT31) and two up-regulated (BST2, MFAP2), as well as one with a non-significant differential expression pattern (GNA15) in our SAGE data were selected for real-time polymerase chain reaction (PCR) in a set of HNSCC samples. Consistent with our statistical analysis, quantitative PCR confirmed the upregulation of BST2 and MFAP2 and the downregulation of KRT31 when samples of HNSCC were compared to tumor-free surgical margins. As expected, GNA15 presented a non-significant differential expression pattern when tumor samples were compared to normal tissues. Conclusion To the best of our knowledge, this is the first study reporting SAGE data in head and neck squamous cell tumors. Statistical analysis was effective in identifying differentially expressed genes reportedly involved in cancer development. The differential expression of a subset of genes was confirmed in additional larynx carcinoma samples and in carcinomas from a distinct head and neck subsite. This result suggests the existence of potential common biomarkers for prognosis and targeted-therapy development in this heterogeneous type of tumor. PMID:19014460

Outcome in Chronic Subdural Hematoma After Subdural vs. Subgaleal Drain.

PubMed

Ishfaq, Asim

2017-07-01

To compare the outcome after surgery for chronic subdural hematoma when the drain is placed in subdural space or subgaleal space. Quasi experimental study. Combined Military Hospital, Lahore, from July 2015 to June 2016. Patients with chronic subdural hematoma of both genders and age, ranging between 55 to 85 years, were included. Patients on antiplatelet/anticoagulant therapy and acute on chronic subdural hematoma were excluded. Patients were divided in two equal groups each depending on whether drain was placed in subgaleal space (Group 1), and subdual space (Group 2), (n=31 patients each). Patients were positioned flat in bed after surgery. Clinical and radiological parameters and clinical outcome were compared between the two groups. Statistical test with significance of p <0.05 was utilized using Statistical Package of Social Sciences (SPSS version 17). Median age of the 62 patients was 72 ±12.5 years. Headache was the most common symptom reported in both groups, (n=47,75.8%) patients. Median thickness of hematoma was 15 ±6.5 mm. Patients with subdural drain placement had more complications such as pneumocephalus 11 (35.4%) vs. 6 (19.3%), and intracerebral hemorrhage 4 (12.9%) vs. 2 (6.4%). Clinical outcome was good in both groups 27 (87%) in Group 1 and 28 (90%) in Group 2. Patients of both groups had good outcome after surgery. Complications like pneumocephalus and intracerebral hemorrhage were more common in subdural location of drain, though not reaching statistically significance level to favor one technique over another.

Analysis of Feature Intervisibility and Cumulative Visibility Using GIS, Bayesian and Spatial Statistics: A Study from the Mandara Mountains, Northern Cameroon

PubMed Central

Wright, David K.; MacEachern, Scott; Lee, Jaeyong

2014-01-01

The locations of diy-geδ-bay (DGB) sites in the Mandara Mountains, northern Cameroon are hypothesized to occur as a function of their ability to see and be seen from points on the surrounding landscape. A series of geostatistical, two-way and Bayesian logistic regression analyses were performed to test two hypotheses related to the intervisibility of the sites to one another and their visual prominence on the landscape. We determine that the intervisibility of the sites to one another is highly statistically significant when compared to 10 stratified-random permutations of DGB sites. Bayesian logistic regression additionally demonstrates that the visibility of the sites to points on the surrounding landscape is statistically significant. The location of sites appears to have also been selected on the basis of lower slope than random permutations of sites. Using statistical measures, many of which are not commonly employed in archaeological research, to evaluate aspects of visibility on the landscape, we conclude that the placement of DGB sites improved their conspicuousness for enhanced ritual, social cooperation and/or competition purposes. PMID:25383883

The comparability of English, French and Dutch scores on the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F): an assessment of differential item functioning in patients with systemic sclerosis.

PubMed

Kwakkenbos, Linda; Willems, Linda M; Baron, Murray; Hudson, Marie; Cella, David; van den Ende, Cornelia H M; Thombs, Brett D

2014-01-01

The Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) is commonly used to assess fatigue in rheumatic diseases, and has shown to discriminate better across levels of the fatigue spectrum than other commonly used measures. The aim of this study was to assess the cross-language measurement equivalence of the English, French, and Dutch versions of the FACIT-F in systemic sclerosis (SSc) patients. The FACIT-F was completed by 871 English-speaking Canadian, 238 French-speaking Canadian and 230 Dutch SSc patients. Confirmatory factor analysis was used to assess the factor structure in the three samples. The Multiple-Indicator Multiple-Cause (MIMIC) model was utilized to assess differential item functioning (DIF), comparing English versus French and versus Dutch patient responses separately. A unidimensional factor model showed good fit in all samples. Comparing French versus English patients, statistically significant, but small-magnitude DIF was found for 3 of 13 items. French patients had 0.04 of a standard deviation (SD) lower latent fatigue scores than English patients and there was an increase of only 0.03 SD after accounting for DIF. For the Dutch versus English comparison, 4 items showed small, but statistically significant, DIF. Dutch patients had 0.20 SD lower latent fatigue scores than English patients. After correcting for DIF, there was a reduction of 0.16 SD in this difference. There was statistically significant DIF in several items, but the overall effect on fatigue scores was minimal. English, French and Dutch versions of the FACIT-F can be reasonably treated as having equivalent scoring metrics.

Electromiography comparison of distal and proximal lower limb muscle activity patterns during external perturbation in subjects with and without functional ankle instability.

PubMed

Kazemi, Khadijeh; Arab, Amir Massoud; Abdollahi, Iraj; López-López, Daniel; Calvo-Lobo, César

2017-10-01

Ankle sprain is one of the most common injuries among athletes and the general population. Most ankle injuries commonly affect the lateral ligament complex. Changes in postural sway and hip abductor muscle strength may be generated after inversion ankle sprain. Therefore, the consequences of ankle injury may affect proximal structures of the lower limb. The aim is to describe and compare the activity patterns of distal and proximal lower limb muscles following external perturbation in individuals with and without functional ankle instability. The sample consisted of 16 women with functional ankle instability and 18 healthy women were recruited to participate in this research. The external perturbation via body jacket using surface electromyography, amplitude and onset of muscle activity of gluteus maximums, gluteus medius, tibialis anterior, and peroneus longus was recorded and analyzed during external perturbation. There were differences between the onset of muscles activity due to perturbation direction in the two groups (healthy and functional ankle instability). In the healthy group, there were statistically significant differences in amplitude of proximal muscle activity with distal muscle activity during front perturbation with eyes open and closed. In the functional ankle instability group; there were statistically significant differences in amplitude of proximal muscle activity with distal muscle activity during perturbation of the front and back with eyes open. There were statistically significant differences in the onset of muscle activity and amplitude of muscle activity, with-in and between groups (P<0.05). Therefore, in the presence of functional ankle instability, activation patterns of the lower limb proximal muscles may be altered. Copyright © 2017 Elsevier B.V. All rights reserved.

Reasons for revision of failed hemiarthroplasty: Are there any differences between unipolar and bipolar?

PubMed

Iamthanaporn, Khanin; Chareancholvanich, Keerati; Pornrattanamaneewong, Chaturong

2018-03-16

Hemiarthroplasty (HA) is an effective procedure for treatment of femoral neck fracture. However, it is debatable whether unipolar or bipolar HA is the most suitable implant. The purpose of this study was to compare the causes of failure and longevity in both types of HA. We retrospectively reviewed 133 cases that underwent revision surgery of HA between 2002 and 2012. The causes of revision surgery were identified and stratified into early (≤ 5 years) failure and late (> 5 years) failure. Survival analyses were performed for each implant type. The common causes for revision were aseptic loosening (49.6%), infection (22.6%) and acetabular erosion (15.0%). Unipolar and bipolar HA were not different in causes for revision, but the unipolar group had a statistically significantly higher number of acetabular erosion events compared with the bipolar group (p = 0.002). In the early period, 24 unipolar HA (52.9%) and 28 bipolar HA (34.1%) failed. There were no statistically significant differences in the numbers of revised HA in each period between the two groups (p = 0.138). The median survival times in the unipolar and bipolar groups were 84.0 ± 24.5 and 120.0 ± 5.5 months, respectively. However, the survival times of both implants were not statistically significantly different. Aseptic loosening was the most common reason for revision surgery after hemiarthroplasty surgery in early and late failures. Unipolar and bipolar hemiarthroplasty were not different in terms of causes of failure and survivorship except bipolar hemiarthroplasty had many fewer acetabular erosion events.

The Comparability of English, French and Dutch Scores on the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F): An Assessment of Differential Item Functioning in Patients with Systemic Sclerosis

PubMed Central

Kwakkenbos, Linda; Willems, Linda M.; Baron, Murray; Hudson, Marie; Cella, David; van den Ende, Cornelia H. M.; Thombs, Brett D.

2014-01-01

Objective The Functional Assessment of Chronic Illness Therapy- Fatigue (FACIT-F) is commonly used to assess fatigue in rheumatic diseases, and has shown to discriminate better across levels of the fatigue spectrum than other commonly used measures. The aim of this study was to assess the cross-language measurement equivalence of the English, French, and Dutch versions of the FACIT-F in systemic sclerosis (SSc) patients. Methods The FACIT-F was completed by 871 English-speaking Canadian, 238 French-speaking Canadian and 230 Dutch SSc patients. Confirmatory factor analysis was used to assess the factor structure in the three samples. The Multiple-Indicator Multiple-Cause (MIMIC) model was utilized to assess differential item functioning (DIF), comparing English versus French and versus Dutch patient responses separately. Results A unidimensional factor model showed good fit in all samples. Comparing French versus English patients, statistically significant, but small-magnitude DIF was found for 3 of 13 items. French patients had 0.04 of a standard deviation (SD) lower latent fatigue scores than English patients and there was an increase of only 0.03 SD after accounting for DIF. For the Dutch versus English comparison, 4 items showed small, but statistically significant, DIF. Dutch patients had 0.20 SD lower latent fatigue scores than English patients. After correcting for DIF, there was a reduction of 0.16 SD in this difference. Conclusions There was statistically significant DIF in several items, but the overall effect on fatigue scores was minimal. English, French and Dutch versions of the FACIT-F can be reasonably treated as having equivalent scoring metrics. PMID:24638101

Factors associated with psychological distress or common mental disorders in migrant populations across the world.

PubMed

Jurado, Dolores; Alarcón, Renato D; Martínez-Ortega, José M; Mendieta-Marichal, Yaiza; Gutiérrez-Rojas, Luis; Gurpegui, Manuel

We systematically review factors associated with the presence of psychological distress or common mental disorders in migrant populations. Articles published between January 2000 and December 2014 were reviewed and 85 applying multivariate statistical analysis were selected. Common mental disorders were significantly associated with socio-demographic and psychological characteristics, as observed in large epidemiological studies on general populations. The probability of common mental disorders occurrence differs significantly among migrant groups according to their region of origin. Moreover, traumatic events prior to migration, forced, unplanned, poorly planned or illegal migration, low level of acculturation, living alone or separated from family in the host country, lack of social support, perceived discrimination, and the length of migrants' residence in the host country all increase the likelihood of CMD. In contrast, language proficiency, family reunification, and perceived social support reduce such probability. Factors related with the risk of psychiatric morbidity among migrants should be taken into account to design preventive strategies. Copyright © 2016 SEP y SEPB. Publicado por Elsevier España, S.L.U. All rights reserved.

Outcomes assessment following treatment of spasmodic dysphonia with botulinum toxin.

PubMed

Courey, M S; Garrett, C G; Billante, C R; Stone, R E; Portell, M D; Smith, T L; Netterville, J L

2000-09-01

Spasmodic dysphonia (SD), a disabling focal dystonia involving the laryngeal musculature, is most commonly treated by the intramuscular injection of botulinum toxin (BTX). Although the treatment is well tolerated and generally produces clinical voice improvement, it has never been statistically shown to alter the patient's perception of voice quality or general health. Declining resources for medical care mandate that treatment outcomes be documented. A prospective analysis of the effects of BTX on the patient's perception of voice and general health was undertaken. The Voice Handicap Index (VHI) and Short Form 36 (SF-36) surveys were administered to patients before treatment and 1 month after. Pretreatment and posttreatment scores were analyzed with a Student's t-test. On the VHI, improvements in the patients' perception of their functional, physical, and emotional voice handicap reached statistical significance (p < or = .0005). On the SF-36, patients had statistically significant improvements in mental health (p < or = .03) and social functioning (p < or = .04). Treatment of SD with BTX significantly lessened the patients' perception of dysphonia. In addition, it improved their social functioning and their perception of their mental health. These outcome measures justify the continued treatment of SD with BTX.

[Mobile phones and head tumours: it is time to read and highlight data in a proper way].

PubMed

Levis, Angelo G; Minicucci, Nadia; Ricci, Paolo; Gennaro, Valerio; Garbisa, Spiridione

2011-01-01

The uncertainty about the relationship between the use of mobile phones (MPs: analogue and digital cellulars, and cordless) and the increase of head tumour risk can be solved by a critical analysis of the methodological elements of both the positive and the negative studies. Results by Hardell indicate a cause/effect relationship: exposures for or latencies from ≥ 10 years to MPs increase by up to 100% the risk of tumour on the same side of the head preferred for phone use (ipsilateral tumours) - which is the only one significantly irradiated - with statistical significance for brain gliomas, meningiomas and acoustic neuromas. On the contrary, studies published under the Interphone project and others produced negative results and are characterised by the substantial underestimation of the risk of tumour. However, also in the Interphone studies a clear and statistically significant increase of ipsilateral head tumours (gliomas, neuromas and parotid gland tumours) is quite common in people having used MPs since or for ≥ 10 years. And also the metaanalyses by Hardell and other Authors, including only the literature data on ipsilateral tumours in people having used MPs since or for ≥ 10 years - and so also part of the Interphone data - still show statistically significant increases of head tumours.

Sex differences in thickness, and folding developments throughout the cortex.

PubMed

Mutlu, A Kadir; Schneider, Maude; Debbané, Martin; Badoud, Deborah; Eliez, Stephan; Schaer, Marie

2013-11-15

While significant differences in male and female brain structures have commonly been reported, only a few studies have focused on the sex differences in the way the cortex matures over time. Here, we investigated cortical thickness maturation between the age of 6 to 30 years, using 209 longitudinally-acquired brain MRI scans. Significant sex differences in the trajectories of cortical thickness change with age were evidenced using non-linear mixed effects models. Similar statistical analyses were computed to quantify the differences between cortical gyrification changes with age in males and females. During adolescence, we observed a statistically significant higher rate of cortical thinning in females compared to males in the right temporal regions, the left temporoparietal junction and the left orbitofrontal cortex. This finding is interpreted as a faster maturation of the social brain areas in females. Concomitantly, statistically significant sex differences in cortical folding changes with age were observed only in one cluster of the right prefrontal regions, suggesting that the mechanisms underlying cortical thickness and gyrification changes with age are quite distinct. Sexual dimorphism in the developmental course of the cortical maturation may be associated with the different age of onset and clinical presentation of many psychiatric disorders between males and females. Copyright © 2013 Elsevier Inc. All rights reserved.

Understanding Statistics - Cancer Statistics

Cancer.gov

Annual reports of U.S. cancer statistics including new cases, deaths, trends, survival, prevalence, lifetime risk, and progress toward Healthy People targets, plus statistical summaries for a number of common cancer types.

A statistical parts-based appearance model of inter-subject variability.

PubMed

Toews, Matthew; Collins, D Louis; Arbel, Tal

2006-01-01

In this article, we present a general statistical parts-based model for representing the appearance of an image set, applied to the problem of inter-subject MR brain image matching. In contrast with global image representations such as active appearance models, the parts-based model consists of a collection of localized image parts whose appearance, geometry and occurrence frequency are quantified statistically. The parts-based approach explicitly addresses the case where one-to-one correspondence does not exist between subjects due to anatomical differences, as parts are not expected to occur in all subjects. The model can be learned automatically, discovering structures that appear with statistical regularity in a large set of subject images, and can be robustly fit to new images, all in the presence of significant inter-subject variability. As parts are derived from generic scale-invariant features, the framework can be applied in a wide variety of image contexts, in order to study the commonality of anatomical parts or to group subjects according to the parts they share. Experimentation shows that a parts-based model can be learned from a large set of MR brain images, and used to determine parts that are common within the group of subjects. Preliminary results indicate that the model can be used to automatically identify distinctive features for inter-subject image registration despite large changes in appearance.

Single Parent Family Structure as a Predictor of Alcohol Use among Secondary School Students: Evidence from Jamaica

PubMed

Oshi, Sarah N; Abel, Wendel D; Agu, Chinwendu F; Omeje, Joachim C; Smith, Patrice Whitehorne; Ukwaja, Kingsley N; Ricketts Roomes, Tana; Meka, Ijeoma A; Weaver, Steve; Rae, Tania; Oshi, Daniel C

2018-04-23

The aim of this study was to examine the potential relationship between Jamaican secondary students’ alcohol drinking habits and their family structure. Methods: Data collected from a nationally representative survey of 3,365 students were analysed. Descriptive and inferential statistics were performed. Results: Out of the 3,365 students, 1,044 (31.0%) were from single-parent families. Single-parent families, married-parent families and common law-parent families were significantly associated with lifetime use of alcohol (AOR= 1.72, 95% CI= 1.06 - 2.79; AOR= 1.73, 95% CI= 1.07- 2.81, AOR= 1.94, 95%CI= 1.17- 3.21 respectively). However, family structure was not significantly associated with past year and past month alcohol use. Students whose parents “sometimes” knew their whereabouts were significantly less likely to use alcohol in their lifetime compared to students whose parents “Always” knew where the students were. Conclusion: Family structure is an independent predictor of alcohol use among high school students in Jamaica. Being from single-parent families, married-parent and common- law parent families were significantly associated with increased likelihood for lifetime alcohol use. Creative Commons Attribution License

Interventions for unilateral refractive amblyopia.

PubMed

Shotton, Kate; Powell, Christine; Voros, Gerasimos; Hatt, Sarah R

2008-10-08

Unilateral refractive amblyopia is a common cause of reduced visual acuity in childhood, but optimal treatment is not well defined. This review examined the treatment effect from spectacles and conventional occlusion. Evaluation of the evidence of the effectiveness of spectacles and or occlusion in the treatment of unilateral refractive amblyopia. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and LILACS. Relevant conference proceedings were manually searched. There were no date or language restrictions. The searches were last run on 7 July 2008. Randomised controlled trials of treatment for unilateral refractive amblyopia by spectacles, with or without occlusion were eligible. We included studies with participants of any age. Two authors independently assessed abstracts identified by the searches. We obtained full text copies and contacted study authors where necessary. Eight trials were eligible for inclusion. Data were extracted from seven. No meta-analysis was performed. For all studies mean acuity (standard deviation (SD)) in the amblyopic eye post treatment is reported.Comparison: Spectacles only versus no treatment (Clarke 2003). Mean (SD) visual acuity: spectacles group 0.31 (0.17); no treatment group 0.42 (0.19). Mean difference (MD) between groups -0.11 (borderline statistical significance: 95% confidence interval (CI) -0.22 to 0.00).Comparison: Spectacles plus occlusion versus no treatment (Clarke 2003). Mean (SD) visual acuity: full treatment 0.22 (0.13); no treatment 0.42 (0.19). Mean difference between the groups -0.20 (statistically significant: 95% CI -0.30 to -0.10).Comparison: Spectacles plus occlusion versus spectacles only: Clarke 2003 MD -0.09 (borderline statistical significance 95% CI, -0.18 to 0.00); PEDIG 2005b; MD -0.15 (not statistically significant 95% CI -0.32 to 0.02); PEDIG 2006a; MD 0.01 (not statistically significant 95% CI -0.08 to 0.10).Comparison: Occlusion regimes. PEDIG 2003a: 2 hours versus 6 hours for moderate amblyopia: MD 0.01 (not statistically significant: 95% CI -0.06 to 0.08); PEDIG 2003b: 6 hours versus full-time for severe amblyopia: MD 0.03 (not statistically significant: 95% CI -0.08 to 0.14). Stewart 2007a: 6 hours versus full-time occlusion: MD -0.12 (not statistically significant: 95% CI -0.27 to 0.03) In some cases of unilateral refractive amblyopia it appears that there is a treatment benefit from refractive correction alone. Where amblyopia persists there is some evidence that adding occlusion further improves vision. It remains unclear which treatment regimes are optimal for individual patients. The nature of any dose/response effect from occlusion still needs to be clarified.

Use of statistical procedures in Brazilian and international dental journals.

PubMed

Ambrosano, Gláucia Maria Bovi; Reis, André Figueiredo; Giannini, Marcelo; Pereira, Antônio Carlos

2004-01-01

A descriptive survey was performed in order to assess the statistical content and quality of Brazilian and international dental journals, and compare their evolution throughout the last decades. The authors identified the reporting and accuracy of statistical techniques in 1000 papers published from 1970 to 2000 in seven dental journals: three Brazilian (Brazilian Dental Journal, Revista de Odontologia da Universidade de Sao Paulo and Revista de Odontologia da UNESP) and four international journals (Journal of the American Dental Association, Journal of Dental Research, Caries Research and Journal of Periodontology). Papers were divided into two time periods: from 1970 to 1989, and from 1990 to 2000. A slight increase in the number of articles that presented some form of statistical technique was noticed for Brazilian journals (from 61.0 to 66.7%), whereas for international journals, a significant increase was observed (65.8 to 92.6%). In addition, a decrease in the number of statistical errors was verified. The most commonly used statistical tests as well as the most frequent errors found in dental journals were assessed. Hopefully, this investigation will encourage dental educators to better plan the teaching of biostatistics, and to improve the statistical quality of submitted manuscripts.

Method of analysis of local neuronal circuits in the vertebrate central nervous system.

PubMed

Reinis, S; Weiss, D S; McGaraughty, S; Tsoukatos, J

1992-06-01

Although a considerable amount of knowledge has been accumulated about the activity of individual nerve cells in the brain, little is known about their mutual interactions at the local level. The method presented in this paper allows the reconstruction of functional relations within a group of neurons as recorded by a single microelectrode. Data are sampled at 10 or 13 kHz. Prominent spikes produced by one or more single cells are selected and sorted by K-means cluster analysis. The activities of single cells are then related to the background firing of neurons in their vicinity. Auto-correlograms of the leading cells, auto-correlograms of the background cells (mass correlograms) and cross-correlograms between these two levels of firing are computed and evaluated. The statistical probability of mutual interactions is determined, and the statistically significant, most common interspike intervals are stored and attributed to real pairs of spikes in the original record. Selected pairs of spikes, characterized by statistically significant intervals between them, are then assembled into a working model of the system. This method has revealed substantial differences between the information processing in the visual cortex, the inferior colliculus, the rostral ventromedial medulla and the ventrobasal complex of the thalamus. Even short 1-s records of the multiple neuronal activity may provide meaningful and statistically significant results.

Addendum to the article: Misuse of null hypothesis significance testing: Would estimation of positive and negative predictive values improve certainty of chemical risk assessment?

PubMed

Bundschuh, Mirco; Newman, Michael C; Zubrod, Jochen P; Seitz, Frank; Rosenfeldt, Ricki R; Schulz, Ralf

2015-03-01

We argued recently that the positive predictive value (PPV) and the negative predictive value (NPV) are valuable metrics to include during null hypothesis significance testing: They inform the researcher about the probability of statistically significant and non-significant test outcomes actually being true. Although commonly misunderstood, a reported p value estimates only the probability of obtaining the results or more extreme results if the null hypothesis of no effect was true. Calculations of the more informative PPV and NPV require a priori estimate of the probability (R). The present document discusses challenges of estimating R.

Research design and statistical methods in Pakistan Journal of Medical Sciences (PJMS)

PubMed Central

Akhtar, Sohail; Shah, Syed Wadood Ali; Rafiq, M.; Khan, Ajmal

2016-01-01

Objective: This article compares the study design and statistical methods used in 2005, 2010 and 2015 of Pakistan Journal of Medical Sciences (PJMS). Methods: Only original articles of PJMS were considered for the analysis. The articles were carefully reviewed for statistical methods and designs, and then recorded accordingly. The frequency of each statistical method and research design was estimated and compared with previous years. Results: A total of 429 articles were evaluated (n=74 in 2005, n=179 in 2010, n=176 in 2015) in which 171 (40%) were cross-sectional and 116 (27%) were prospective study designs. A verity of statistical methods were found in the analysis. The most frequent methods include: descriptive statistics (n=315, 73.4%), chi-square/Fisher’s exact tests (n=205, 47.8%) and student t-test (n=186, 43.4%). There was a significant increase in the use of statistical methods over time period: t-test, chi-square/Fisher’s exact test, logistic regression, epidemiological statistics, and non-parametric tests. Conclusion: This study shows that a diverse variety of statistical methods have been used in the research articles of PJMS and frequency improved from 2005 to 2015. However, descriptive statistics was the most frequent method of statistical analysis in the published articles while cross-sectional study design was common study design. PMID:27022365

Common statistical and research design problems in manuscripts submitted to high-impact psychiatry journals: what editors and reviewers want authors to know.

PubMed

Harris, Alex H S; Reeder, Rachelle; Hyun, Jenny K

2009-10-01

Journal editors and statistical reviewers are often in the difficult position of catching serious problems in submitted manuscripts after the research is conducted and data have been analyzed. We sought to learn from editors and reviewers of major psychiatry journals what common statistical and design problems they most often find in submitted manuscripts and what they wished to communicate to authors regarding these issues. Our primary goal was to facilitate communication between journal editors/reviewers and researchers/authors and thereby improve the scientific and statistical quality of research and submitted manuscripts. Editors and statistical reviewers of 54 high-impact psychiatry journals were surveyed to learn what statistical or design problems they encounter most often in submitted manuscripts. Respondents completed the survey online. The authors analyzed survey text responses using content analysis procedures to identify major themes related to commonly encountered statistical or research design problems. Editors and reviewers (n=15) who handle manuscripts from 39 different high-impact psychiatry journals responded to the survey. The most commonly cited problems regarded failure to map statistical models onto research questions, improper handling of missing data, not controlling for multiple comparisons, not understanding the difference between equivalence and difference trials, and poor controls in quasi-experimental designs. The scientific quality of psychiatry research and submitted reports could be greatly improved if researchers became sensitive to, or sought consultation on frequently encountered methodological and analytic issues.

Thyroid disorders and the prevalence of antithyroid antibodies in Shiraz population.

PubMed

Karimi, Fariba; Kalantarhormozi, Mohammad Reza; Dabbaghmanesh, Mohammad Hossein; Ranjbar Omrani, Gholamhossein

2014-05-01

Thyroid dysfunction is a common health problem affecting millions of patients worldwide. Autoimmune thyroid disorders are among the most common autoimmune disorders. In this population-based study, we assessed the prevalence of abnormal thyroid function, antithyroid antibodies and the probable relationship between them in Shiraz, southern Iran. Serum thyrotropin (TSH) was determined in 981 subjects (66.8% female and 33.2% male; mean age: 39.1 ± 14.3 years), who were selected with stratified random sampling. Because of the preponderance of females over males, we performed the statistical analyses using sex-weighted data (50% for each sex). Also, antithyroid peroxidase antibodies (TPOAb), and antithyroglobulin antibodies (TgAb) were measured in two random subgroups of 376 and 537 patients respectively). Thyromegaly detected on physical examination. In this cross-sectional study, 8.1% of participants had elevated serum TSH level and 3.4% had low serum TSH level. A statistically significant relationship was found between gender and thyromegaly and TSH values. Positive TPOAb and positive TgAb were detected in 17% and 5.1% of participants respectively. In addition, a significant relationship was observed between elevated TSH levels and positive results for both antibodies. Detectable levels of thyroid antibodies correlated with female sex, while no correlation was observed between detectable levels of thyroid antibodies and thyromegaly. Thyroid disorders, especially elevated TSH level, are common. It seems that autoimmune mechanisms are strongly involved in the etiology of hypothyroidism in this area.

Are Level of Education and Employment Related to Symptoms of Common Mental Disorders in Current and Retired Professional Footballers?

PubMed

Gouttebarge, Vincent; Aoki, Haruhito; Verhagen, Evert; Kerkhoffs, Gino

2016-06-01

Mental disorders have become a topic of increasing interest in research due to their serious consequences for quality of life and functioning. The objective of this study was to explore the relationship of level of education, employment status and working hours with symptoms of common mental disorders (distress, anxiety/depression, sleep disturbance, adverse alcohol behaviour, smoking, adverse nutritional behaviour) among current and retired professional footballers. Cross-sectional analyses were conducted on baseline questionnaires from an ongoing prospective cohort study among current and retired professional footballers. Based on validated scales, an electronic questionnaire was set up and distributed by players' unions in 11 countries across three continents. A total of 607 current professional footballers (mean age of 27 years) and 219 retired professional footballers (mean age of 35 years) were involved in the study. Among retired professional footballers, statistically significant negative correlations were found between employment status and symptoms of distress and anxiety/depression (P < 0.05), as well as between number of working hours and symptoms of anxiety/depression (P < 0.05). No other statistically significant associations were found among retired players. Among current professional footballers, level of education was not associated with symptoms of common mental disorders. Among retired professional footballers, employment status as well as a higher number of working hours was weakly correlated to symptoms of distress and anxiety/depression. Combining a football career with sustainable attention for educational and career planning might be important and of high priority.

Awareness and knowledge among internal medicine house-staff for dose adjustment of commonly used medications in patients with CKD.

PubMed

Surana, Sikander; Kumar, Neeru; Vasudeva, Amita; Shaikh, Gulvahid; Jhaveri, Kenar D; Shah, Hitesh; Malieckal, Deepa; Fogel, Joshua; Sidhu, Gurwinder; Rubinstein, Sofia

2017-01-17

Drug dosing errors result in adverse patient outcomes and are more common in patients with chronic kidney disease (CKD). As internists treat the majority of patients with CKD, we study if Internal Medicine house-staff have awareness and knowledge about the correct dosage of commonly used medications for those with CKD. A cross-sectional survey was performed and included 341 participants. The outcomes were the awareness of whether a medication needs dose adjustment in patients with CKD and whether there was knowledge for the level of glomerular filtration rate (GFR) a medication needs to be adjusted. The overall pattern for all post-graduate year (PGY) groups in all medication classes was a lack of awareness and knowledge. For awareness, there were statistically significant increased mean differences for PGY2 and PGY3 as compared to PGY1 for allergy, endocrine, gastrointestinal, and rheumatologic medication classes but not for analgesic, cardiovascular, and neuropsychotropic medication classes. For knowledge, there were statistically significant increased mean differences for PGY2 and PGY3 as compared to PGY1 for allergy, cardiovascular, endocrine, and gastrointestinal, medication classes but not for analgesic, neuropsychotropic, and rheumatologic medication classes. Internal Medicine house-staff across all levels of training demonstrated poor awareness and knowledge for many medication classes in CKD patients. Internal Medicine house-staff should receive more nephrology exposure and formal didactic educational training during residency to better manage complex treatment regimens and prevent medication dosing errors.

Relationship Between Nutritional Status and Intensity of Common Intestinal Helminths Among Children in Enugu, South-East Nigeria

PubMed Central

Ilechukwu, GC; Ilechukwu, CGA; Ubesie, AC; Onyire, NB; Emechebe, G; Eze, JC

2014-01-01

Background: Intestinal helminthiasis is associated with malnutrition in children. Aim: The objective of this study was to determine the intensity and effect of the common intestinal helminths on the nutritional status of children in Enugu, Nigeria. Subjects and Methods: A cross-sectional study of 460 children conducted in Enugu metropolis, south-east Nigeria between August and September 2003. Their stools were analyzed at the research laboratory of the Federal Ministry of Health, National Arbovirus and Vector Research Center, Enugu. The intensity of the common intestinal helminths was determined using the standard Kato-Katz method of fresh stool samples. The classification intensity of helminthic infestation was according to the World Health Organization classification. Data were analyzed using Statistical Software for Social Sciences version 11.0 (Chicago IL, USA). P < 0.05 was regarded as statistically significant. Results: 452 of 460 children (98.3%) had normal height for age, weight for age and weight for height Z-scores. Six of the 460 children (1.3% were wasted), 1/460 stunted (0.2%) and 1/460 wasted and stunted (0.2%). 150 out of 460 (32.6%) studied were infected with helminths. There was no significant relationship between the intensity of helminth infection and the nutritional status of the children. Conclusion: Although the prevalence of helminthiasis in children in Enugu was high, intensity of helminthiasis in these children was mainly mild. Hence, majority of them had normal weight and height measurements for age and sex. PMID:25184077

SURVEILLANCE FOR AVIAN INFLUENZA VIRUS IN WILD BIRDS IN POLAND, 2008-15.

PubMed

Świętoń, Edyta; Wyrostek, Krzysztof; Jóźwiak, Michał; Olszewska-Tomczyk, Monika; Domańska-Blicharz, Katarzyna; Meissner, Włodzimierz; Włodarczyk, Radosław; Minias, Piotr; Janiszewski, Tomasz; Minta, Zenon; Śmietanka, Krzysztof

2017-04-01

We tested wild birds in Poland during 2008-15 for avian influenza virus (AIV). We took 10,312 swabs and feces samples from 6,314 live birds representing 12 orders and 84 bird species, mostly from orders Anseriformes and Charadriiformes, for testing and characterization by various PCR methods. From PCR-positive samples, we attempted to isolate and subtype the virus. The RNA of AIV was detected in 1.8% (95% confidence interval [CI], 1.5-2.1%) of birds represented by 48 Mallards ( Anas platyrhynchos ), 11 Mute Swans ( Cygnus olor ), 48 Common Teals ( Anas crecca ), three Black-headed Gulls (Chroicocephalus ridibundus), one Common Coot ( Fulica atra ), one Garganey (Spatula querquedula), and one unidentified bird species. Overall, the prevalence of AIV detection in Mallards and Mute Swans (the most frequently sampled species) was 2.0% (95% CI, 1.4-2.5%) and 0.5% (95% CI, 0.2-0.8%), respectively; the difference was statistically significant (P=0.000). Hemagglutinin subtypes from H1 to H13 were identified, including H5 and H7 low pathogenic AIV subtypes. Mallards and Common Teals harbored the greatest diversity of subtypes. We observed seasonality of viral detection in Mallards, with higher AIV prevalence in late summer and autumn than in winter and spring. In addition, two peaks in AIV prevalence in summer (August) and autumn (November) were demonstrated for Mallards. The prevalence of AIV in Mute Swans did not show any statistically significant seasonal patterns.

Familial associations between polycystic ovarian syndrome and common diseases.

PubMed

Moini, Ashraf; Eslami, Bita

2009-03-01

The goal of this study was focused on two subjects. First, to determine possible association between PCOS and family history of breast cancer, ovarian cancer, endometrial cancer, heart attack, thrombosis, diabetes and cardiovascular disease (CVD). Second, to evaluate maternal and paternal transmission in PCOS patients with positive family history of a disease. A cross-sectional study was conducted in 549 infertile women (273 with PCOS and 276 controls) in Arash hospital of Tehran, Iran, between 2007 and 2008 by using questionnaire. In this analysis, there were significantly increased number of women with the positive family history of diabetes among PCOS group (28.21% vs. 19.20%, p=0.01). Meanwhile, four women in PCOS group had self history of diabetes while no one in the control group reported diabetes. A statistically significant positive family history of breast cancer was found among the control group (4.35% vs. 1.30%, p=0.02). Endometrial cancer and diabetes were observed in mother or mother's side of the family but heart attack and thrombosis manifested in father or father's side of the family more. There were no statistically significant differences in a positive individual or family history of ovarian cancer, endometrial cancer, heart attack, thrombosis and CVD between the two groups. In the present study, women and their relatives with PCOS had an increased prevalence of diabetes and it is more common in mother's side of the family.

Employing the Gini coefficient to measure participation inequality in treatment-focused Digital Health Social Networks.

PubMed

van Mierlo, Trevor; Hyatt, Douglas; Ching, Andrew T

2016-01-01

Digital Health Social Networks (DHSNs) are common; however, there are few metrics that can be used to identify participation inequality. The objective of this study was to investigate whether the Gini coefficient, an economic measure of statistical dispersion traditionally used to measure income inequality, could be employed to measure DHSN inequality. Quarterly Gini coefficients were derived from four long-standing DHSNs. The combined data set included 625,736 posts that were generated from 15,181 actors over 18,671 days. The range of actors (8-2323), posts (29-28,684), and Gini coefficients (0.15-0.37) varied. Pearson correlations indicated statistically significant associations between number of actors and number of posts (0.527-0.835, p  < .001), and Gini coefficients and number of posts (0.342-0.725, p  < .001). However, the association between Gini coefficient and number of actors was only statistically significant for the addiction networks (0.619 and 0.276, p  < .036). Linear regression models had positive but mixed R 2 results (0.333-0.527). In all four regression models, the association between Gini coefficient and posts was statistically significant ( t  = 3.346-7.381, p  < .002). However, unlike the Pearson correlations, the association between Gini coefficient and number of actors was only statistically significant in the two mental health networks ( t  = -4.305 and -5.934, p  < .000). The Gini coefficient is helpful in measuring shifts in DHSN inequality. However, as a standalone metric, the Gini coefficient does not indicate optimal numbers or ratios of actors to posts, or effective network engagement. Further, mixed-methods research investigating quantitative performance metrics is required.

Reporting Statistical Results in Medical Journals

PubMed Central

Arifin, Wan Nor; Sarimah, Abdullah; Norsa’adah, Bachok; Najib Majdi, Yaacob; Siti-Azrin, Ab Hamid; Kamarul Imran, Musa; Aniza, Abd Aziz; Naing, Lin

2016-01-01

Statistical editors of the Malaysian Journal of Medical Sciences (MJMS) must go through many submitted manuscripts, focusing on the statistical aspect of the manuscripts. However, the editors notice myriad styles of reporting the statistical results, which are not standardised among the authors. This could be due to the lack of clear written instructions on reporting statistics in the guidelines for authors. The aim of this editorial is to briefly outline reporting methods for several important and common statistical results. It will also address a number of common mistakes made by the authors. The editorial will serve as a guideline for authors aiming to publish in the MJMS as well as in other medical journals. PMID:27904419

Epidemiology of musculoskeletal injury in the California film and motion picture industry.

PubMed

Kusnezov, Nicholas A; Yazdanshenas, Hamed; Garcia, Eddie; Shamie, Arya N

2016-06-01

Musculoskeletal injury exerts a significant burden on US industry. The purpose of this study was to investigate the frequency and characteristics of musculoskeletal injuries in the California (CA) film and motion picture (FMP) industry which may result in unforeseen morbidity and mortality. We reviewed the workers' compensation (WC) claims database of the Workers' Compensation Insurance Rating Bureau of California (WCIRB) and employment statistics through the US Bureau of Labor Statistics (BLS). We analyzed the frequency, type, body part affected, and cause of musculoskeletal injuries. From 2003 to 2009, there were 3505 WC claims of which 94.4% were musculoskeletal. In the CA FMP industry, the most common injuries were strains (38.4%), sprains (12.2%), and fractures (11.7%). The most common sites of isolated injury were the knee (18.9%), lower back (15.0%), and ankle (8.6%). Isolated musculoskeletal spine injuries represented 19.3% of all injuries. The most common causes of injury were work-directed activity (36.0%) and falls (25.5%). We present the first report on the unique profile of musculoskeletal injury claims in the FMP industry. This data provides direction for improvement of workplace safety.

Epidemiology of musculoskeletal injury in the California film and motion picture industry

PubMed Central

Kusnezov, Nicholas A.; Yazdanshenas, Hamed; Garcia, Eddie

2016-01-01

Introduction Musculoskeletal injury exerts a significant burden on US industry. The purpose of this study was to investigate the frequency and characteristics of musculoskeletal injuries in the California (CA) film and motion picture (FMP) industry which may result in unforeseen morbidity and mortality. Methods We reviewed the workers’ compensation (WC) claims database of the Workers’ Compensation Insurance Rating Bureau of California (WCIRB) and employment statistics through the US Bureau of Labor Statistics (BLS). We analyzed the frequency, type, body part affected, and cause of musculoskeletal injuries. Results From 2003 to 2009, there were 3505 WC claims of which 94.4% were musculoskeletal. In the CA FMP industry, the most common injuries were strains (38.4%), sprains (12.2%), and fractures (11.7%). The most common sites of isolated injury were the knee (18.9%), lower back (15.0%), and ankle (8.6%). Isolated musculoskeletal spine injuries represented 19.3% of all injuries. The most common causes of injury were work-directed activity (36.0%) and falls (25.5%). Conclusion We present the first report on the unique profile of musculoskeletal injury claims in the FMP industry. This data provides direction for improvement of workplace safety. PMID:26812757

Individual variation in circadian rhythms of sleep, EEG, temperature, and activity among monkeys - Implications for regulatory mechanisms.

NASA Technical Reports Server (NTRS)

Crowley, T. J.; Halberg, F.; Kripke, D. F.; Pegram, G. V.

1971-01-01

Investigation of circadian rhythms in a number of variables related to sleep, EEG, temperature, and motor activity in rhesus monkeys on an LD 12:12 schedule. Circadian rhythms were found to appear in each of 15 variables investigated. Statistical procedures assessed the variables for evidence of common regulation in these aspects of their circadian rhythms: acrophase (timing), amplitude (extent of change), and level (24-hr mean value). Patterns appearing in the data suggested that the circadian rhythms of certain variables are regulated in common. The circadian modulation of activity in the beta and sigma frequency bands of the EEG was correlated with statistical significance in acrophase, level, and amplitude. The delta frequency band appeared to be under circadian rhythm regulation distinct from that of the other bands. The circadian rhythm of REM stage sleep was like that of beta activity in level and amplitude. The data indicate that REM stage may share some common regulation of circadian timing with both stage 3-4 sleep and with temperature. Generally, however, the circadian rhythm of temperature appeared to bear little relation to the circadian rhythms of motor activity, EEG, or sleep.

Tract-Based Spatial Statistics in Preterm-Born Neonates Predicts Cognitive and Motor Outcomes at 18 Months.

PubMed

Duerden, E G; Foong, J; Chau, V; Branson, H; Poskitt, K J; Grunau, R E; Synnes, A; Zwicker, J G; Miller, S P

2015-08-01

Adverse neurodevelopmental outcome is common in children born preterm. Early sensitive predictors of neurodevelopmental outcome such as MR imaging are needed. Tract-based spatial statistics, a diffusion MR imaging analysis method, performed at term-equivalent age (40 weeks) is a promising predictor of neurodevelopmental outcomes in children born very preterm. We sought to determine the association of tract-based spatial statistics findings before term-equivalent age with neurodevelopmental outcome at 18-months corrected age. Of 180 neonates (born at 24-32-weeks' gestation) enrolled, 153 had DTI acquired early at 32 weeks' postmenstrual age and 105 had DTI acquired later at 39.6 weeks' postmenstrual age. Voxelwise statistics were calculated by performing tract-based spatial statistics on DTI that was aligned to age-appropriate templates. At 18-month corrected age, 166 neonates underwent neurodevelopmental assessment by using the Bayley Scales of Infant Development, 3rd ed, and the Peabody Developmental Motor Scales, 2nd ed. Tract-based spatial statistics analysis applied to early-acquired scans (postmenstrual age of 30-33 weeks) indicated a limited significant positive association between motor skills and axial diffusivity and radial diffusivity values in the corpus callosum, internal and external/extreme capsules, and midbrain (P < .05, corrected). In contrast, for term scans (postmenstrual age of 37-41 weeks), tract-based spatial statistics analysis showed a significant relationship between both motor and cognitive scores with fractional anisotropy in the corpus callosum and corticospinal tracts (P < .05, corrected). Tract-based spatial statistics in a limited subset of neonates (n = 22) scanned at <30 weeks did not significantly predict neurodevelopmental outcomes. The strength of the association between fractional anisotropy values and neurodevelopmental outcome scores increased from early-to-late-acquired scans in preterm-born neonates, consistent with brain dysmaturation in this population. © 2015 by American Journal of Neuroradiology.

Surgical site infections following colorectal cancer surgery: a randomized prospective trial comparing common and advanced antimicrobial dressing containing ionic silver.

PubMed

Biffi, Roberto; Fattori, Luca; Bertani, Emilio; Radice, Davide; Rotmensz, Nicole; Misitano, Pasquale; Cenciarelli, Sabine; Chiappa, Antonio; Tadini, Liliana; Mancini, Marina; Pesenti, Giovanni; Andreoni, Bruno; Nespoli, Angelo

2012-05-23

An antimicrobial dressing containing ionic silver was found effective in reducing surgical-site infection in a preliminary study of colorectal cancer elective surgery. We decided to test this finding in a randomized, double-blind trial. Adults undergoing elective colorectal cancer surgery at two university-affiliated hospitals were randomly assigned to have the surgical incision dressed with Aquacel Ag Hydrofiber dressing or a common dressing. To blind the patient and the nursing and medical staff to the nature of the dressing used, scrub nurses covered Aquacel Ag Hydrofiber with a common wound dressing in the experimental arm, whereas a double common dressing was applied to patients of control group. The primary end-point of the study was the occurrence of any surgical-site infection within 30 days of surgery. A total of 112 patients (58 in the experimental arm and 54 in the control group) qualified for primary end-point analysis. The characteristics of the patient population and their surgical procedures were similar. The overall rate of surgical-site infection was lower in the experimental group (11.1% center 1, 17.5% center 2; overall 15.5%) than in controls (14.3% center 1, 24.2% center 2, overall 20.4%), but the observed difference was not statistically significant (P = 0.451), even with respect to surgical-site infection grade 1 (superficial) versus grades 2 and 3, or grade 1 and 2 versus grade 3. This randomized trial did not confirm a statistically significant superiority of Aquacel Ag Hydrofiber dressing in reducing surgical-site infection after elective colorectal cancer surgery. Clinicaltrials.gov: NCT00981110.

Attitude toward Christianity and paranormal belief among 13- to 16-yr.-old students.

PubMed

Williams, Emyr; Francis, Leslie J; Robbins, Mandy

2006-08-01

A small but statistically significant positive correlation (r = .17) was found in a sample of 279 13- to 16-yr.-old students in Wales between scores on the Francis Scale of Attitude toward Christianity and on a new Index of Paranormal Belief. These data suggest that there is little common variance between attitude toward Christianity and belief in the paranormal.

BIPM Time Activities Update

DTIC Science & Technology

2009-11-01

transfer technique as GPS PPP and GLONASS Common View, - creation of new statistical tools in order remove outliers in TWSTFT time links, making the...in-view [1] using single- and dual-frequency receivers and TWSTFT links [2-4]. Significant progress has been made in time transfer for clock...of differentially calibrated GLONASS receivers [8]. TWSTFT links are often affected by outliers which are difficult to remove; for safe handling, a

Common and rare genetic markers of lipid variation in subjects with type 2 diabetes from the ACCORD clinical trial.

PubMed

Marvel, Skylar W; Rotroff, Daniel M; Wagner, Michael J; Buse, John B; Havener, Tammy M; McLeod, Howard L; Motsinger-Reif, Alison A

2017-01-01

Individuals with type 2 diabetes are at an increased risk of cardiovascular disease. Alterations in circulating lipid levels, total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides (TG) are heritable risk factors for cardiovascular disease. Here we conduct a genome-wide association study (GWAS) of common and rare variants to investigate associations with baseline lipid levels in 7,844 individuals with type 2 diabetes from the ACCORD clinical trial. DNA extracted from stored blood samples from ACCORD participants were genotyped using the Affymetrix Axiom Biobank 1 Genotyping Array. After quality control and genotype imputation, association of common genetic variants (CV), defined as minor allele frequency (MAF) ≥ 3%, with baseline levels of TC, LDL, HDL, and TG was tested using a linear model. Rare variant (RV) associations (MAF < 3%) were conducted using a suite of methods that collapse multiple RV within individual genes. Many statistically significant CV ( p  < 1 × 10 -8 ) replicate findings in large meta-analyses in non-diabetic subjects. RV analyses also confirmed findings in other studies, whereas significant RV associations with CNOT2 , HPN-AS1 , and SIRPD appear to be novel ( q  < 0.1). Here we present findings for the largest GWAS of lipid levels in people with type 2 diabetes to date. We identified 17 statistically significant ( p  < 1 × 10 -8 ) associations of CV with lipid levels in 11 genes or chromosomal regions, all of which were previously identified in meta-analyses of mostly non-diabetic cohorts. We also identified 13 associations in 11 genes based on RV, several of which represent novel findings.

Common and rare genetic markers of lipid variation in subjects with type 2 diabetes from the ACCORD clinical trial

PubMed Central

Wagner, Michael J.; Buse, John B.; Havener, Tammy M.; McLeod, Howard L.

2017-01-01

Background Individuals with type 2 diabetes are at an increased risk of cardiovascular disease. Alterations in circulating lipid levels, total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides (TG) are heritable risk factors for cardiovascular disease. Here we conduct a genome-wide association study (GWAS) of common and rare variants to investigate associations with baseline lipid levels in 7,844 individuals with type 2 diabetes from the ACCORD clinical trial. Methods DNA extracted from stored blood samples from ACCORD participants were genotyped using the Affymetrix Axiom Biobank 1 Genotyping Array. After quality control and genotype imputation, association of common genetic variants (CV), defined as minor allele frequency (MAF) ≥ 3%, with baseline levels of TC, LDL, HDL, and TG was tested using a linear model. Rare variant (RV) associations (MAF < 3%) were conducted using a suite of methods that collapse multiple RV within individual genes. Results Many statistically significant CV (p < 1 × 10−8) replicate findings in large meta-analyses in non-diabetic subjects. RV analyses also confirmed findings in other studies, whereas significant RV associations with CNOT2, HPN-AS1, and SIRPD appear to be novel (q < 0.1). Discussion Here we present findings for the largest GWAS of lipid levels in people with type 2 diabetes to date. We identified 17 statistically significant (p < 1 × 10−8) associations of CV with lipid levels in 11 genes or chromosomal regions, all of which were previously identified in meta-analyses of mostly non-diabetic cohorts. We also identified 13 associations in 11 genes based on RV, several of which represent novel findings. PMID:28480134

Power-up: A Reanalysis of 'Power Failure' in Neuroscience Using Mixture Modeling.

PubMed

Nord, Camilla L; Valton, Vincent; Wood, John; Roiser, Jonathan P

2017-08-23

Recently, evidence for endemically low statistical power has cast neuroscience findings into doubt. If low statistical power plagues neuroscience, then this reduces confidence in the reported effects. However, if statistical power is not uniformly low, then such blanket mistrust might not be warranted. Here, we provide a different perspective on this issue, analyzing data from an influential study reporting a median power of 21% across 49 meta-analyses (Button et al., 2013). We demonstrate, using Gaussian mixture modeling, that the sample of 730 studies included in that analysis comprises several subcomponents so the use of a single summary statistic is insufficient to characterize the nature of the distribution. We find that statistical power is extremely low for studies included in meta-analyses that reported a null result and that it varies substantially across subfields of neuroscience, with particularly low power in candidate gene association studies. Therefore, whereas power in neuroscience remains a critical issue, the notion that studies are systematically underpowered is not the full story: low power is far from a universal problem. SIGNIFICANCE STATEMENT Recently, researchers across the biomedical and psychological sciences have become concerned with the reliability of results. One marker for reliability is statistical power: the probability of finding a statistically significant result given that the effect exists. Previous evidence suggests that statistical power is low across the field of neuroscience. Our results present a more comprehensive picture of statistical power in neuroscience: on average, studies are indeed underpowered-some very seriously so-but many studies show acceptable or even exemplary statistical power. We show that this heterogeneity in statistical power is common across most subfields in neuroscience. This new, more nuanced picture of statistical power in neuroscience could affect not only scientific understanding, but potentially policy and funding decisions for neuroscience research. Copyright © 2017 Nord, Valton et al.

Did the 1997 balanced budget act reduce use of physical and occupational therapy services?

PubMed

Latham, Nancy K; Jette, Alan M; Ngo, Long H; Soukup, Jane; Iezzoni, Lisa I

2008-05-01

To investigate whether use of physical therapy (PT) and occupational therapy (OT) services decreased after the passage of the 1997 Balanced Budget Act (BBA). Data from the nationally representative Medicare Current Beneficiary Survey (MCBS) were merged with Medicare claims data. We conducted cross-sectional analyses of data from 1995 (n=7978), 1999 (n=7863), and 2001 (n=7973). All analyses used MCBS sampling weights to provide estimates that can be generalized to the Medicare population with 5 common conditions. Skilled nursing facilities (SNFs), home health agencies, inpatient rehabilitation facilities (IRFs), and outpatient rehabilitation settings. Medicare beneficiaries who participated in the MCBS survey in each of the study years and had 1 or more of the following conditions: acute stroke, acute myocardial infarction, chronic obstructive pulmonary disease, arthritis or degenerative joint disease, or mobility problems. Not applicable. Percentage of persons meeting our inclusion criteria who received PT or OT in each setting, and total units of PT and OT received in each setting. Multivariable logistic regression revealed no statistically significant differences in the proportion of people who met our inclusion criteria who used PT or OT from home health agencies across the 3 time points. For SNFs, an increase in the odds of receiving PT was statistically significant from 1995 to 1999 (odds ratio [OR]=1.42; 95% confidence interval [CI], 1.19-1.69) and 1995 to 2001 (OR=1.69; 95% CI, 1.39-2.05). For IRF and outpatient settings, a significant increase was observed between 1995 and 2001 (OR=1.71, OR=1.27, respectively). For OT, a statistically significant increase was observed for IRF and outpatient rehabilitation settings from 1995 to 2001. For SNF, the increase was statistically significant from 1995 to 1999 and 1995 to 2001. Mean total PT and OT units received also increased across all settings from 1995 to 2001 except for IRFs. Despite BBA mandates restricting postacute care expenditures, this nationally representative study showed no decreases in the percentage of Medicare beneficiaries with 5 common diagnoses receiving PT and/or OT across all settings and no decreases in units of PT and/or OT services received between 1995 and 2001 except for those in IRFs. This study suggests that the delivery of PT and OT services did not decline among persons with conditions for which rehabilitation services are often clinically indicated.

Variation in passing standards for graduation-level knowledge items at UK medical schools.

PubMed

Taylor, Celia A; Gurnell, Mark; Melville, Colin R; Kluth, David C; Johnson, Neil; Wass, Val

2017-06-01

Given the absence of a common passing standard for students at UK medical schools, this paper compares independently set standards for common 'one from five' single-best-answer (multiple-choice) items used in graduation-level applied knowledge examinations and explores potential reasons for any differences. A repeated cross-sectional study was conducted. Participating schools were sent a common set of graduation-level items (55 in 2013-2014; 60 in 2014-2015). Items were selected against a blueprint and subjected to a quality review process. Each school employed its own standard-setting process for the common items. The primary outcome was the passing standard for the common items by each medical school set using the Angoff or Ebel methods. Of 31 invited medical schools, 22 participated in 2013-2014 (71%) and 30 (97%) in 2014-2015. Schools used a mean of 49 and 53 common items in 2013-2014 and 2014-2015, respectively, representing around one-third of the items in the examinations in which they were embedded. Data from 19 (61%) and 26 (84%) schools, respectively, met the inclusion criteria for comparison of standards. There were statistically significant differences in the passing standards set by schools in both years (effect sizes (f 2 ): 0.041 in 2013-2014 and 0.218 in 2014-2015; both p < 0.001). The interquartile range of standards was 5.7 percentage points in 2013-2014 and 6.5 percentage points in 2014-2015. There was a positive correlation between the relative standards set by schools in the 2 years (Pearson's r = 0.57, n = 18, p = 0.014). Time allowed per item, method of standard setting and timing of examination in the curriculum did not have a statistically significant impact on standards. Independently set standards for common single-best-answer items used in graduation-level examinations vary across UK medical schools. Further work to examine standard-setting processes in more detail is needed to help explain this variability and develop methods to reduce it. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Selected Statistics from the Common Core of Data: School Year 2011-12. First Look. NCES 2013-441

ERIC Educational Resources Information Center

Keaton, Patrick

2013-01-01

The Common Core of Data (CCD) is an annual collection of public elementary and secondary education data by the National Center for Education Statistics (NCES) in the Institute of Education Sciences of the U.S. Department of Education. The data presented in this report are selected from the three nonfiscal components of the Common Core of Data…

Leptospirosis and Human Immunodeficiency Virus Co-Infection Among Febrile Inpatients in Northern Tanzania

PubMed Central

Biggs, Holly M.; Galloway, Renee L.; Bui, Duy M.; Morrissey, Annie B.; Maro, Venance P.

2013-01-01

Abstract Background Leptospirosis and human immunodeficiency virus (HIV) infection are prevalent in many areas, including northern Tanzania, yet little is known about their interaction. Methods We enrolled febrile inpatients at two hospitals in Moshi, Tanzania, over 1 year and performed HIV antibody testing and the microscopic agglutination test (MAT) for leptospirosis. Confirmed leptospirosis was defined as ≥four-fold rise in MAT titer between acute and convalescent serum samples, and probable leptospirosis was defined as any reciprocal MAT titer ≥800. Results Confirmed or probable leptospirosis was found in 70 (8.4%) of 831 participants with at least one serum sample tested. At total of 823 (99.0%) of 831 participants had HIV testing performed, and 203 (24.7%) were HIV infected. Among HIV-infected participants, 9 (4.4%) of 203 had confirmed or probable leptospirosis, whereas among HIV-uninfected participants 61 (9.8%) of 620 had leptospirosis. Leptospirosis was less prevalent among HIV-infected as compared to HIV-uninfected participants [odds ratio (OR) 0.43, p=0.019]. Among those with leptospirosis, HIV-infected patients more commonly presented with features of severe sepsis syndrome than HIV-uninfected patients, but differences were not statistically significant. Among HIV-infected patients, severe immunosuppression was not significantly different between those with and without leptospirosis (p=0.476). Among HIV-infected adolescents and adults, median CD4 percent and median CD4 count were higher among those with leptospirosis as compared to those with other etiologies of febrile illness, but differences in CD4 count did not reach statistical significance (p=0.015 and p=0.089, respectively). Conclusions Among febrile inpatients in northern Tanzania, leptospirosis was not more prevalent among HIV-infected patients. Although some indicators of leptospirosis severity were more common among HIV-infected patients, a statistically significant difference was not demonstrated. Among HIV-infected patients, those with leptospirosis were not more immunosuppressed relative to those with other etiologies of febrile illness. PMID:23663165

Analysis of Statistical Methods and Errors in the Articles Published in the Korean Journal of Pain

PubMed Central

Yim, Kyoung Hoon; Han, Kyoung Ah; Park, Soo Young

2010-01-01

Background Statistical analysis is essential in regard to obtaining objective reliability for medical research. However, medical researchers do not have enough statistical knowledge to properly analyze their study data. To help understand and potentially alleviate this problem, we have analyzed the statistical methods and errors of articles published in the Korean Journal of Pain (KJP), with the intention to improve the statistical quality of the journal. Methods All the articles, except case reports and editorials, published from 2004 to 2008 in the KJP were reviewed. The types of applied statistical methods and errors in the articles were evaluated. Results One hundred and thirty-nine original articles were reviewed. Inferential statistics and descriptive statistics were used in 119 papers and 20 papers, respectively. Only 20.9% of the papers were free from statistical errors. The most commonly adopted statistical method was the t-test (21.0%) followed by the chi-square test (15.9%). Errors of omission were encountered 101 times in 70 papers. Among the errors of omission, "no statistics used even though statistical methods were required" was the most common (40.6%). The errors of commission were encountered 165 times in 86 papers, among which "parametric inference for nonparametric data" was the most common (33.9%). Conclusions We found various types of statistical errors in the articles published in the KJP. This suggests that meticulous attention should be given not only in the applying statistical procedures but also in the reviewing process to improve the value of the article. PMID:20552071

[Statistical analysis of German radiologic periodicals: developmental trends in the last 10 years].

PubMed

Golder, W

1999-09-01

To identify which statistical tests are applied in German radiological publications, to what extent their use has changed during the last decade, and which factors might be responsible for this development. The major articles published in "ROFO" and "DER RADIOLOGE" during 1988, 1993 and 1998 were reviewed for statistical content. The contributions were classified by principal focus and radiological subspecialty. The methods used were assigned to descriptive, basal and advanced statistics. Sample size, significance level and power were established. The use of experts' assistance was monitored. Finally, we calculated the so-called cumulative accessibility of the publications. 525 contributions were found to be eligible. In 1988, 87% used descriptive statistics only, 12.5% basal, and 0.5% advanced statistics. The corresponding figures in 1993 and 1998 are 62 and 49%, 32 and 41%, and 6 and 10%, respectively. Statistical techniques were most likely to be used in research on musculoskeletal imaging and articles dedicated to MRI. Six basic categories of statistical methods account for the complete statistical analysis appearing in 90% of the articles. ROC analysis is the single most common advanced technique. Authors make increasingly use of statistical experts' opinion and programs. During the last decade, the use of statistical methods in German radiological journals has fundamentally improved, both quantitatively and qualitatively. Presently, advanced techniques account for 20% of the pertinent statistical tests. This development seems to be promoted by the increasing availability of statistical analysis software.

Improving Service Delivery in a County Health Department WIC Clinic: An Application of Statistical Process Control Techniques

PubMed Central

Boe, Debra Thingstad; Parsons, Helen

2009-01-01

Local public health agencies are challenged to continually improve service delivery, yet they frequently operate with constrained resources. Quality improvement methods and techniques such as statistical process control are commonly used in other industries, and they have recently been proposed as a means of improving service delivery and performance in public health settings. We analyzed a quality improvement project undertaken at a local Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) clinic to reduce waiting times and improve client satisfaction with a walk-in nutrition education service. We used statistical process control techniques to evaluate initial process performance, implement an intervention, and assess process improvements. We found that implementation of these techniques significantly reduced waiting time and improved clients' satisfaction with the WIC service. PMID:19608964

Determination of quality parameters from statistical analysis of routine TLD dosimetry data.

PubMed

German, U; Weinstein, M; Pelled, O

2006-01-01

Following the as low as reasonably achievable (ALARA) practice, there is a need to measure very low doses, of the same order of magnitude as the natural background, and the limits of detection of the dosimetry systems. The different contributions of the background signals to the total zero dose reading of thermoluminescence dosemeter (TLD) cards were analysed by using the common basic definitions of statistical indicators: the critical level (L(C)), the detection limit (L(D)) and the determination limit (L(Q)). These key statistical parameters for the system operated at NRC-Negev were quantified, based on the history of readings of the calibration cards in use. The electronic noise seems to play a minor role, but the reading of the Teflon coating (without the presence of a TLD crystal) gave a significant contribution.

The sumLINK statistic for genetic linkage analysis in the presence of heterogeneity.

PubMed

Christensen, G B; Knight, S; Camp, N J

2009-11-01

We present the "sumLINK" statistic--the sum of multipoint LOD scores for the subset of pedigrees with nominally significant linkage evidence at a given locus--as an alternative to common methods to identify susceptibility loci in the presence of heterogeneity. We also suggest the "sumLOD" statistic (the sum of positive multipoint LOD scores) as a companion to the sumLINK. sumLINK analysis identifies genetic regions of extreme consistency across pedigrees without regard to negative evidence from unlinked or uninformative pedigrees. Significance is determined by an innovative permutation procedure based on genome shuffling that randomizes linkage information across pedigrees. This procedure for generating the empirical null distribution may be useful for other linkage-based statistics as well. Using 500 genome-wide analyses of simulated null data, we show that the genome shuffling procedure results in the correct type 1 error rates for both the sumLINK and sumLOD. The power of the statistics was tested using 100 sets of simulated genome-wide data from the alternative hypothesis from GAW13. Finally, we illustrate the statistics in an analysis of 190 aggressive prostate cancer pedigrees from the International Consortium for Prostate Cancer Genetics, where we identified a new susceptibility locus. We propose that the sumLINK and sumLOD are ideal for collaborative projects and meta-analyses, as they do not require any sharing of identifiable data between contributing institutions. Further, loci identified with the sumLINK have good potential for gene localization via statistical recombinant mapping, as, by definition, several linked pedigrees contribute to each peak.

Comparability of ecological quality boundaries in the Mediterranean basin using freshwater benthic invertebrates. Statistical options and implications.

PubMed

Feio, M J; Ferreira, J; Buffagni, A; Erba, S; Dörflinger, G; Ferréol, M; Munné, A; Prat, N; Tziortzis, I; Urbanič, G

2014-04-01

Within the Mediterranean region each country has its own assessment method based on aquatic macroinvertebrates. However, independently of the classification system, quality assessments should be comparable across members of the European Commission, which means, among others, that the boundaries between classes should not deviate significantly. Here we check for comparability between High-Good and Good-Moderate classifications, through the use of a common metric. Additionally, we discuss the influence of the conceptual and statistical approaches used to calculate a common boundary within the Mediterranean countries participating in the Intercalibration Exercise (e.g., using individual national type-boundaries, one value for each common type or an average boundary by country; weighted average, median) in the overall outcome. All methods, except for the IBMWP (the Iberian BMWP) when applied to temporary rivers, were highly correlated (0.82

Metabolic syndrome-related composite factors over 5 years in the STANISLAS family study: genetic heritability and common environmental influences.

PubMed

Herbeth, Bernard; Samara, Anastasia; Ndiaye, Coumba; Marteau, Jean-Brice; Berrahmoune, Hind; Siest, Gérard; Visvikis-Siest, Sophie

2010-06-03

We estimated genetic heritability and common environmental influences for various traits related to metabolic syndrome in young families from France. At entrance and after 5 years, nineteen traits related to metabolic syndrome were measured in a sample of families drawn from the STANISLAS study. In addition, 5 aggregates of these traits were identified using factor analysis. At entrance, genetic heritability was high (20 to 44%) for plasma lipids and lipoproteins, uric acid, fasting glucose, and the related clusters "risk lipids" and "protective lipids". Intermediate or low genetic heritability (less than 20%) was shown for triglycerides, adiposity indices, blood pressure, hepatic enzyme activity, inflammatory makers and the related clusters: "liver enzymes", "adiposity/blood pressure" and "inflammation". Moreover, common environmental influences were significant for all the parameters. With regard to 5-year changes, polygenic variance was low and not statistically significant for any of the individual variables or clusters whereas shared environment influence was significant. In these young families, genetic heritability of metabolic syndrome-related traits was generally lower than previously reported while the common environmental influences were greater. In addition, only shared environment contributed to short-term changes of these traits. Copyright 2010 Elsevier B.V. All rights reserved.

Investigating the cognitive structure of stereotypes: Generic beliefs about groups predict social judgments better than statistical beliefs.

PubMed

Hammond, Matthew D; Cimpian, Andrei

2017-05-01

Stereotypes are typically defined as beliefs about groups, but this definition is underspecified. Beliefs about groups can be generic or statistical. Generic beliefs attribute features to entire groups (e.g., men are strong), whereas statistical beliefs encode the perceived prevalence of features (e.g., how common it is for men to be strong). In the present research, we sought to determine which beliefs-generic or statistical-are more central to the cognitive structure of stereotypes. Specifically, we tested whether generic or statistical beliefs are more influential in people's social judgments, on the assumption that greater functional importance indicates greater centrality in stereotype structure. Relative to statistical beliefs, generic beliefs about social groups were significantly stronger predictors of expectations (Studies 1-3) and explanations (Study 4) for unfamiliar individuals' traits. In addition, consistent with prior evidence that generic beliefs are cognitively simpler than statistical beliefs, generic beliefs were particularly predictive of social judgments for participants with more intuitive (vs. analytic) cognitive styles and for participants higher (vs. lower) in authoritarianism, who tend to view outgroups in simplistic, all-or-none terms. The present studies suggest that generic beliefs about groups are more central than statistical beliefs to the cognitive structure of stereotypes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Selecting a Classification Ensemble and Detecting Process Drift in an Evolving Data Stream

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

Heredia-Langner, Alejandro; Rodriguez, Luke R.; Lin, Andy

2015-09-30

We characterize the commercial behavior of a group of companies in a common line of business using a small ensemble of classifiers on a stream of records containing commercial activity information. This approach is able to effectively find a subset of classifiers that can be used to predict company labels with reasonable accuracy. Performance of the ensemble, its error rate under stable conditions, can be characterized using an exponentially weighted moving average (EWMA) statistic. The behavior of the EWMA statistic can be used to monitor a record stream from the commercial network and determine when significant changes have occurred. Resultsmore » indicate that larger classification ensembles may not necessarily be optimal, pointing to the need to search the combinatorial classifier space in a systematic way. Results also show that current and past performance of an ensemble can be used to detect when statistically significant changes in the activity of the network have occurred. The dataset used in this work contains tens of thousands of high level commercial activity records with continuous and categorical variables and hundreds of labels, making classification challenging.« less

A Note on Comparing the Power of Test Statistics at Low Significance Levels.

PubMed

Morris, Nathan; Elston, Robert

2011-01-01

It is an obvious fact that the power of a test statistic is dependent upon the significance (alpha) level at which the test is performed. It is perhaps a less obvious fact that the relative performance of two statistics in terms of power is also a function of the alpha level. Through numerous personal discussions, we have noted that even some competent statisticians have the mistaken intuition that relative power comparisons at traditional levels such as α = 0.05 will be roughly similar to relative power comparisons at very low levels, such as the level α = 5 × 10 -8 , which is commonly used in genome-wide association studies. In this brief note, we demonstrate that this notion is in fact quite wrong, especially with respect to comparing tests with differing degrees of freedom. In fact, at very low alpha levels the cost of additional degrees of freedom is often comparatively low. Thus we recommend that statisticians exercise caution when interpreting the results of power comparison studies which use alpha levels that will not be used in practice.

Comparative evaluation of the accuracy of linear measurements between cone beam computed tomography and 3D microtomography.

PubMed

Mangione, Francesca; Meleo, Deborah; Talocco, Marco; Pecci, Raffaella; Pacifici, Luciano; Bedini, Rossella

2013-01-01

The aim of this study was to evaluate the influence of artifacts on the accuracy of linear measurements estimated with a common cone beam computed tomography (CBCT) system used in dental clinical practice, by comparing it with microCT system as standard reference. Ten bovine bone cylindrical samples containing one implant each, able to provide both points of reference and image quality degradation, have been scanned by CBCT and microCT systems. Thanks to the software of the two systems, for each cylindrical sample, two diameters taken at different levels, by using implants different points as references, have been measured. Results have been analyzed by ANOVA and a significant statistically difference has been found. Due to the obtained results, in this work it is possible to say that the measurements made with the two different instruments are still not statistically comparable, although in some samples were obtained similar performances and therefore not statistically significant. With the improvement of the hardware and software of CBCT systems, in the near future the two instruments will be able to provide similar performances.

[Study of quality of life in adults with common variable immunodeficiency by using the Questionnaire SF-36].

PubMed

López-Pérez, Patricia; Miranda-Novales, Guadalupe; Segura-Méndez, Nora Hilda; Del Rivero-Hernández, Leonel; Cambray-Gutiérrez, Cesar; Chávez-García, Aurora

2014-01-01

Quality of life is a multidimensional concept that includes physical, emotional and social components associated with the disease. The use of tools to assess the Quality of Life Health Related (HRQOL) has increased in recent decades. Common variable immunodeficiency (CVID) is the most commonly diagnosed primary immunodeficiency. To evaluate the quality of life in patients with CVID using the questionnaire SF -36. A descriptive cross-sectional survey included 23 patients diagnosed with CVID, belonging to the Immunodeficiency Clinic Service of Allergology and Clinical Immunology in CMN Siglo XXI, IMSS. The questionnaire SF- 36 validated in Spanish was applied. descriptive statistics with simple frequencies and percentages, inferential statistics: Fisher exact test and ANOVA to compare means. The study involved 23 patients, 14 women (60%) and 9 men (40%), mean age 38.6 ± 14.7 years. The highest score was obtained in 83% emotional role. Dimensions with further deterioration in both genders were: 54% general health, vitality 59% and physical performance 72%. No differences were found regarding gender. The only issue in which statistically significant differences were found in patients with more than 3 comorbidities was change in health status in the past year (p=0.007). Patients with severe comorbidities, such as haematologicaloncological (leukemias, lymphomas, neoplasms), and pulmonary (severe bronchiectasis) showed further deterioration in the aspects of physical performance 73% and 64% emotional role. 65% of patients reported an improvement in health status in 74% in the last year. Adult patients with CVID show deterioration in different dimensions, particularly in the areas of general health, vitality and physical performance. Patients with severe comorbidities such as leukemia, lymphomas, malignancies and severe bronchiectasis show further deterioration in some aspects of quality of life, especially in physical performance and emotional role. A higher number of comorbidities was significantly associated with a lower score in changing health. The questionnaire SF-36 is useful for evaluating the quality of life of our patients with CVID.

Genetic polymorphisms associated with breast cancer in malaysian cohort.

PubMed

Chahil, Jagdish Kaur; Munretnam, Khamsigan; Samsudin, Nurulhafizah; Lye, Say Hean; Hashim, Nikman Adli Nor; Ramzi, Nurul Hanis; Velapasamy, Sharmila; Wee, Ler Lian; Alex, Livy

2015-04-01

Genome-wide association studies have discovered multiple single nucleotide polymorphisms (SNPs) associated with the risk of common diseases. The objective of this study was to demonstrate the replication of previously published SNPs that showed statistical significance for breast cancer in the Malaysian population. In this case-control study, 80 subjects for each group were recruited from various hospitals in Malaysia. A total of 768 SNPs were genotyped and analyzed to distinguish risk and protective alleles. A total of three SNPs were found to be associated with increased risk of breast cancer while six SNPs showed protective effect. All nine were statistically significant SNPs (p ≤ 0.01), five SNPs from previous studies were successfully replicated in our study. Significant modifiable (diet) and non-modifiable (family history of breast cancer in first degree relative) risk factors were also observed. We identified nine SNPs from this study to be either conferring susceptibility or protection to breast cancer which may serve as potential markers in risk prediction.

Common pitfalls in statistical analysis: Odds versus risk

PubMed Central

Ranganathan, Priya; Aggarwal, Rakesh; Pramesh, C. S.

2015-01-01

In biomedical research, we are often interested in quantifying the relationship between an exposure and an outcome. “Odds” and “Risk” are the most common terms which are used as measures of association between variables. In this article, which is the fourth in the series of common pitfalls in statistical analysis, we explain the meaning of risk and odds and the difference between the two. PMID:26623395

Differential Expression and Clinical Significance of DNA Methyltransferase 3B (DNMT3B), Phosphatase and Tensin Homolog (PTEN) and Human MutL Homologs 1 (hMLH1) in Endometrial Carcinomas.

PubMed

Li, Wenting; Wang, Ying; Fang, Xinzhi; Zhou, Mei; Li, Yiqun; Dong, Ying; Wang, Ruozheng

2017-02-21

BACKGROUND The aim of this study was to investigate the expression and the clinicopathologic significance of DNA methyltransferase 3B (DNMT3B), phosphatase and tensin homolog (PTEN) and human MutL homologs 1 (hMLH1) in endometrial carcinomas between Han and Uygur women in Xinjiang. MATERIAL AND METHODS The expression of DNMT3B, PTEN, and hMLH1 in endometrial carcinomas were assessed by immunohistochemistry, followed by an analysis of their relationship to clinical-pathological features and prognosis. RESULTS There were a 61.7% (95/154) overexpression of DNMT3B, 50.0% (77/154) loss of PTEN expression and 18.2% (28/154) loss of hMLH1 expression. The expression of DNMT3B and PTEN in endometrial carcinomas was statistically significantly different between Uygur women and Han women (p=0.001, p=0.010, respectively). DNMT3B expression was statistically significant based on the grade of endometrial carcinomas (p=0.031). PTEN loss was statistically significant between endometrioid carcinomas (ECs) and non endometrioid carcinomas (NECs) (p=0.040). DNMT3B expression was statistically significant in different myometrial invasion groups in Uygur women (p=0.010). Furthermore, the correlation of DNMT3B and PTEN expression was significant in endometrial carcinomas (p=0.021). PTEN expression was statistically significant in the overall survival (OS) rate of women with endometrial cancers (p=0.041). CONCLUSIONS Our findings suggest that PTEN and DNMT3B possess common regulation features as well as certain ethnic differences in expression between Han women and Uygur women. An interaction may exist in the pathogenesis of endometrial carcinoma. DNMT3B was expressed differently in cases of myometrial invasion and PTEN was associated with OS, which suggested that these molecular markers may be useful in the evaluation of the biological behavior of endometrial carcinomas and may be useful indicators of prognosis in women with endometrial carcinomas.

Differential Expression and Clinical Significance of DNA Methyltransferase 3B (DNMT3B), Phosphatase and Tensin Homolog (PTEN) and Human MutL Homologs 1 (hMLH1) in Endometrial Carcinomas

PubMed Central

Li, Wenting; Wang, Ying; Fang, Xinzhi; Zhou, Mei; Li, Yiqun; Dong, Ying; Wang, Ruozheng

2017-01-01

Background The aim of this study was to investigate the expression and the clinicopathologic significance of DNA methyltransferase 3B (DNMT3B), phosphatase and tensin homolog (PTEN) and human MutL homologs 1 (hMLH1) in endometrial carcinomas between Han and Uygur women in Xinjiang. Material/Methods The expression of DNMT3B, PTEN, and hMLH1 in endometrial carcinomas were assessed by immunohistochemistry, followed by an analysis of their relationship to clinical-pathological features and prognosis. Results There were a 61.7% (95/154) overexpression of DNMT3B, 50.0% (77/154) loss of PTEN expression and 18.2% (28/154) loss of hMLH1 expression. The expression of DNMT3B and PTEN in endometrial carcinomas was statistically significantly different between Uygur women and Han women (p=0.001, p=0.010, respectively). DNMT3B expression was statistically significant based on the grade of endometrial carcinomas (p=0.031). PTEN loss was statistically significant between endometrioid carcinomas (ECs) and non endometrioid carcinomas (NECs) (p=0.040). DNMT3B expression was statistically significant in different myometrial invasion groups in Uygur women (p=0.010). Furthermore, the correlation of DNMT3B and PTEN expression was significant in endometrial carcinomas (p=0.021). PTEN expression was statistically significant in the overall survival (OS) rate of women with endometrial cancers (p=0.041). Conclusions Our findings suggest that PTEN and DNMT3B possess common regulation features as well as certain ethnic differences in expression between Han women and Uygur women. An interaction may exist in the pathogenesis of endometrial carcinoma. DNMT3B was expressed differently in cases of myometrial invasion and PTEN was associated with OS, which suggested that these molecular markers may be useful in the evaluation of the biological behavior of endometrial carcinomas and may be useful indicators of prognosis in women with endometrial carcinomas. PMID:28220037

Blind image quality assessment based on aesthetic and statistical quality-aware features

NASA Astrophysics Data System (ADS)

Jenadeleh, Mohsen; Masaeli, Mohammad Masood; Moghaddam, Mohsen Ebrahimi

2017-07-01

The main goal of image quality assessment (IQA) methods is the emulation of human perceptual image quality judgments. Therefore, the correlation between objective scores of these methods with human perceptual scores is considered as their performance metric. Human judgment of the image quality implicitly includes many factors when assessing perceptual image qualities such as aesthetics, semantics, context, and various types of visual distortions. The main idea of this paper is to use a host of features that are commonly employed in image aesthetics assessment in order to improve blind image quality assessment (BIQA) methods accuracy. We propose an approach that enriches the features of BIQA methods by integrating a host of aesthetics image features with the features of natural image statistics derived from multiple domains. The proposed features have been used for augmenting five different state-of-the-art BIQA methods, which use statistical natural scene statistics features. Experiments were performed on seven benchmark image quality databases. The experimental results showed significant improvement of the accuracy of the methods.

Performance metrics for the assessment of satellite data products: an ocean color case study

EPA Science Inventory

Performance assessment of ocean color satellite data has generally relied on statistical metrics chosen for their common usage and the rationale for selecting certain metrics is infrequently explained. Commonly reported statistics based on mean squared errors, such as the coeffic...

Awareness of osteoporosis in postmenopausal Indian women: An evaluation of Osteoporosis Health Belief Scale.

PubMed

Gopinathan, Nirmal Raj; Sen, Ramesh Kumar; Behera, Prateek; Aggarwal, Sameer; Khandelwal, Niranjan; Sen, Mitali

2016-01-01

The level of awareness about osteoporosis in postmenopausal women who are the common sufferers. This study aims to evaluate the level of awareness in postmenopausal women using the Osteoporosis Health Belief Scale (OHBS). Osteoporosis has emerged as a common health problem in geriatric population. A proactive role needs to be played for preventing its consequences. Before initiating any preventive measures, an evaluation of awareness level of the target population is necessary. The questionnaire-based study design was used for this study. A questionnaire (OHBS)-based study in 100 postmenopausal women in Chandigarh was conducted. The bone mineral density (BMD) was measured in each case by dual energy X-ray absorptiometry. Height, weight, and body mass index (BMI) of the participants were noted. Statistical analysis was conducted to evaluate any correlation between the various components of the OHBS and the BMD. No statistically significant difference was noted in the seven component parameters of OHBS among the normal, osteopenic, and osteoporotic women suggesting that the health belief regarding susceptibility is not much different between the three groups of the study population. A statistically significant difference between the mean BMI of normal and osteoporotic population was noted. The results show that there is a great deficit in the awareness level of postmenopausal Indian women regarding osteoporosis. Most of the women were unaware of the condition and the means to prevent it. The study emphasizes that health care professionals have lot of ground to cover to decrease the incidence of osteoporosis and its associated health problem.

The statistical average of optical properties for alumina particle cluster in aircraft plume

NASA Astrophysics Data System (ADS)

Li, Jingying; Bai, Lu; Wu, Zhensen; Guo, Lixin

2018-04-01

We establish a model for lognormal distribution of monomer radius and number of alumina particle clusters in plume. According to the Multi-Sphere T Matrix (MSTM) theory, we provide a method for finding the statistical average of optical properties for alumina particle clusters in plume, analyze the effect of different distributions and different detection wavelengths on the statistical average of optical properties for alumina particle cluster, and compare the statistical average optical properties under the alumina particle cluster model established in this study and those under three simplified alumina particle models. The calculation results show that the monomer number of alumina particle cluster and its size distribution have a considerable effect on its statistical average optical properties. The statistical average of optical properties for alumina particle cluster at common detection wavelengths exhibit obvious differences, whose differences have a great effect on modeling IR and UV radiation properties of plume. Compared with the three simplified models, the alumina particle cluster model herein features both higher extinction and scattering efficiencies. Therefore, we may find that an accurate description of the scattering properties of alumina particles in aircraft plume is of great significance in the study of plume radiation properties.

Better P-curves: Making P-curve analysis more robust to errors, fraud, and ambitious P-hacking, a Reply to Ulrich and Miller (2015).

PubMed

Simonsohn, Uri; Simmons, Joseph P; Nelson, Leif D

2015-12-01

When studies examine true effects, they generate right-skewed p-curves, distributions of statistically significant results with more low (.01 s) than high (.04 s) p values. What else can cause a right-skewed p-curve? First, we consider the possibility that researchers report only the smallest significant p value (as conjectured by Ulrich & Miller, 2015), concluding that it is a very uncommon problem. We then consider more common problems, including (a) p-curvers selecting the wrong p values, (b) fake data, (c) honest errors, and (d) ambitiously p-hacked (beyond p < .05) results. We evaluate the impact of these common problems on the validity of p-curve analysis, and provide practical solutions that substantially increase its robustness. (c) 2015 APA, all rights reserved).

Associations between dietary acrylamide intake and plasma sex hormone levels

PubMed Central

Hogervorst, Janneke G.; Fortner, Renee T.; Mucci, Lorelei A.; Tworoger, Shelley S.; Eliassen, A. Heather; Hankinson, Susan E.; Wilson, Kathryn M.

2013-01-01

Background The rodent carcinogen acrylamide was discovered in 2002 in commonly consumed foods. Epidemiological studies have observed positive associations between acrylamide intake and endometrial, ovarian and breast cancer risks, which suggests that acrylamide may have sex-hormonal effects. Methods We cross-sectionally investigated the relationship between acrylamide intake and plasma levels of sex hormones and SHBG among 687 postmenopausal and 1300 premenopausal controls from nested case-control studies within the Nurses’ Health Studies. Results There were no associations between acrylamide and sex hormones or SHBG among premenopausal women overall or among never-smokers. Among normal-weight premenopausal women, acrylamide intake was statistically significantly positively associated with luteal total and free estradiol levels. Among postmenopausal women overall and among never-smokers, acrylamide was borderline statistically significantly associated with lower estrone sulfate levels but not with other estrogens, androgens, prolactin or SHBG. Among normal weight women, (borderline) statistically significant inverse associations were noted for estrone, free estradiol, estrone sulfate, DHEA, and prolactin, while statistically significant positive associations for testosterone and androstenedione were observed among overweight women. Conclusions Overall, this study did not show conclusive associations between acrylamide intake and sex hormones that would lend unequivocal biological plausibility to the observed increased risks of endometrial, ovarian and breast cancer. The association between acrylamide and sex hormones may differ by menopausal and overweight status. We recommend other studies investigate the relationship between acrylamide and sex hormones in women, specifically using acrylamide biomarkers. Impact The present study showed some interesting associations between acrylamide intake and sex hormones that urgently need confirmation. PMID:23983241

Prevalence of dental anomalies in deciduous dentition and its association with succedaneous dentition: A cross-sectional study of 4180 South Indian children.

PubMed

Shilpa, G; Gokhale, Niraj; Mallineni, Sreekanth Kumar; Nuvvula, Sivakumar

2017-01-01

The objective of this study was to estimate the prevalence of dental anomalies in primary dentition of Indian population. This cross-sectional study was conducted on 4180 children in the age of 2-6 years. Anomalies were classified based on Kreiborg criteria. The term "double tooth" was used to avoid misinterpretation between gemination. and fusion. Patients having radiographs were also examined for associated dental anomalies in permanent dentition. The occurrence and gender prevalence were evaluated using descriptive statistics. About 95. (2.27%) children exhibited at least one dental anomaly. Thirty.seven children showed 51 missing teeth. (0.88%), mostly in lower right incisors with a statistically significant difference between arches. (P = 0.0056) Nine children. (0.21%) had supernumerary teeth commonly in the right maxilla. Two cases of oligodontia. (0.04%) and talon cusps. (0.04%) and one case of triple tooth. (0.02%) were observed. Forty children. (0.95%) had 43 double teeth mostly in the right mandible with a statistically significant difference between the arches. (P = 0.0105). No significant difference was observed based on gender and arch, but they were statistically significant between the right and left sides. (P = 0.018). Among the children with radiographs available, 45% showed anomalies in the succedaneous dentition. The prevalence rates of children with double tooth, hypodontia, and hyperdontia in our study are 0.95%, 0.88%, and 0.21%, respectively. The overall prevalence rate of anomalies among boys was higher than girls.

Optical properties of mice skin for optical therapy relevant wavelengths: influence of gender and pigmentation

NASA Astrophysics Data System (ADS)

Sabino, C. P.; Deana, A. M.; Silva, D. F. T.; França, C. M.; Yoshimura, T. M.; Ribeiro, M. S.

2015-03-01

Red and near-infrared light have been widely employed in optical therapies. Skin is the most common optical barrier in non-invasive techniques and in many cases it is the target tissue itself. Consequently, to optimize the outcomes brought by lightbased therapies, the optical properties of skin tissue must be very well elucidated. In the present study, we evaluated the dorsal skin optical properties of albino (BALB/c) and pigmented (C57BL/6) mice using the Kubelka-Munk photon transport model. We evaluated samples from male and female young mice of both strains. Analysis was performed for wavelengths at 630, 660, 780, 810 and 905 nm due to their prevalent use in optical therapies, such as low-level light (or laser) and photodynamic therapies. Spectrophotometric measurements of diffuse transmittance and reflectance were performed using a single integrating sphere coupled to a proper spectrophotometer. Statistic analysis was made by two-way ANOVA, with Tukey as post-test and Levenne and Shapiro-Wilks as pre-tests. Statistical significance was considered when p<0.05. Our results show only a slight transmittance increment (<10 %) as wavelengths are increased from 630 to 905 nm, and no statistical significance was observed. Albino male mice present reduced transmittance levels for all wavelengths. The organization and abundance of skin composing tissues significantly influence its scattering optical properties although absorption remains constant. We conclude that factors such as subcutaneous adiposity and connective tissue structure can have statistically significant influence on mice skin optical properties and these factors have relevant variations among different gender and strains.

Addressing the mischaracterization of extreme rainfall in regional climate model simulations - A synoptic pattern based bias correction approach

NASA Astrophysics Data System (ADS)

Li, Jingwan; Sharma, Ashish; Evans, Jason; Johnson, Fiona

2018-01-01

Addressing systematic biases in regional climate model simulations of extreme rainfall is a necessary first step before assessing changes in future rainfall extremes. Commonly used bias correction methods are designed to match statistics of the overall simulated rainfall with observations. This assumes that change in the mix of different types of extreme rainfall events (i.e. convective and non-convective) in a warmer climate is of little relevance in the estimation of overall change, an assumption that is not supported by empirical or physical evidence. This study proposes an alternative approach to account for the potential change of alternate rainfall types, characterized here by synoptic weather patterns (SPs) using self-organizing maps classification. The objective of this study is to evaluate the added influence of SPs on the bias correction, which is achieved by comparing the corrected distribution of future extreme rainfall with that using conventional quantile mapping. A comprehensive synthetic experiment is first defined to investigate the conditions under which the additional information of SPs makes a significant difference to the bias correction. Using over 600,000 synthetic cases, statistically significant differences are found to be present in 46% cases. This is followed by a case study over the Sydney region using a high-resolution run of the Weather Research and Forecasting (WRF) regional climate model, which indicates a small change in the proportions of the SPs and a statistically significant change in the extreme rainfall over the region, although the differences between the changes obtained from the two bias correction methods are not statistically significant.

Qualitative Literature Review of the Prevalence of Depression in Medical Students Compared to Students in Non-medical Degrees.

PubMed

Bacchi, Stephen; Licinio, Julio

2015-06-01

The purpose of this study is to review studies published in English between 1 January 2000 and 16 June 2014, in peer-reviewed journals, that have assessed the prevalence of depression, comparing medical students and non-medical students with a single evaluation method. The databases PubMed, Medline, EMBASE, PsycINFO, and Scopus were searched for eligible articles. Searches used combinations of the Medical Subject Headings medical student and depression. Titles and abstracts were reviewed to determine eligibility before full-text articles were retrieved, which were then also reviewed. Twelve studies met eligibility criteria. Non-medical groups surveyed included dentistry, business, humanities, nursing, pharmacy, and architecture students. One study found statistically significant results suggesting that medical students had a higher prevalence of depression than groups of non-medical students; five studies found statistically significant results indicating that the prevalence of depression in medical students was less than that in groups of non-medical students; four studies found no statistically significant difference, and two studies did not report on the statistical significance of their findings. One study was longitudinal, and 11 studies were cross-sectional. While there are limitations to these comparisons, in the main, the reviewed literature suggests that medical students have similar or lower rates of depression compared to certain groups of non-medical students. A lack of longitudinal studies meant that potential common underlying causes could not be discerned, highlighting the need for further research in this area. The high rates of depression among medical students indicate the continuing need for interventions to reduce depression.

Locating Encrypted Data Hidden Among Non-Encrypted Data Using Statistical Tools

DTIC Science & Technology

2007-03-01

length of a compressed sequence). If a bit sequence can be significantly compressed , then it is not random. Lempel - Ziv Compression Test This test...communication, targeting, and a host other of tasks. This software will most assuredly contain classified data or algorithms requiring protection in...containing the classified data and algorithms . As the program is executed the solider would have access to the common unclassified tasks, however, to

Changes of Polyphenolic Substances in the Anatomical Parts of Buckwheat (Fagopyrum esculentum Moench.) during Its Growth Phases

PubMed Central

Bystricka, Judita; Musilova, Janette; Tomas, Jan; Vollmannova, Alena; Lachman, Jaromir; Kavalcova, Petra

2014-01-01

In this study the changes of total polyphenolics in different anatomical parts (stems, leaves, flowers and seeds) of common buckwheat (Fagopyrum esculentum Moench.) during vegetation period were analysed. The content of total polyphenolics was evaluated in growth phase I (formation of buds), phase II (at the beginning of flowering), phase III (full blossoming) and phase IV (full ripeness). In all growth phases (GP) the stems and leaves were evaluated and statistically significant differences in polyphenolics content between the two parts were confirmed. Statistically significant differences (p < 0.01) in polyphenolics content (in GP II and III) between stems and leaves; and between stems and flowers were found. In flowers an average of 13.8 times higher and in leaves 6 times higher concentration of polyphenolics in comparison with stems was measured. In GP III the content of polyphenolics in common buckwheat was following: flowers > leaves > achene > stems. In flowers an average of 11.9 times higher, in leaves 8.3 times higher and in achenes 5.9 times higher contents of polyphenolics compared with stems were found. In GP III and IV (leaves, achenes, stems) the leaves contained in average 20 times higher and achenes 5.6 times higher polyphenolics than stems. PMID:28234337

Complex Adaptive System Models and the Genetic Analysis of Plasma HDL-Cholesterol Concentration

PubMed Central

Rea, Thomas J.; Brown, Christine M.; Sing, Charles F.

2006-01-01

Despite remarkable advances in diagnosis and therapy, ischemic heart disease (IHD) remains a leading cause of morbidity and mortality in industrialized countries. Recent efforts to estimate the influence of genetic variation on IHD risk have focused on predicting individual plasma high-density lipoprotein cholesterol (HDL-C) concentration. Plasma HDL-C concentration (mg/dl), a quantitative risk factor for IHD, has a complex multifactorial etiology that involves the actions of many genes. Single gene variations may be necessary but are not individually sufficient to predict a statistically significant increase in risk of disease. The complexity of phenotype-genotype-environment relationships involved in determining plasma HDL-C concentration has challenged commonly held assumptions about genetic causation and has led to the question of which combination of variations, in which subset of genes, in which environmental strata of a particular population significantly improves our ability to predict high or low risk phenotypes. We document the limitations of inferences from genetic research based on commonly accepted biological models, consider how evidence for real-world dynamical interactions between HDL-C determinants challenges the simplifying assumptions implicit in traditional linear statistical genetic models, and conclude by considering research options for evaluating the utility of genetic information in predicting traits with complex etiologies. PMID:17146134

Prospective elementary teachers' conceptions of multidigit number: exemplifying a replication framework for mathematics education

NASA Astrophysics Data System (ADS)

Jacobson, Erik; Simpson, Amber

2018-04-01

Replication studies play a critical role in scientific accumulation of knowledge, yet replication studies in mathematics education are rare. In this study, the authors replicated Thanheiser's (Educational Studies in Mathematics 75:241-251, 2010) study of prospective elementary teachers' conceptions of multidigit number and examined the main claim that most elementary pre-service teachers think about digits incorrectly at least some of the time. Results indicated no statistically significant difference in the distribution of conceptions between the original and replication samples and, moreover, no statistically significant differences in the distribution of sub-conceptions among prospective teachers with the most common conception. These results suggest confidence is warranted both in the generality of the main claim and in the utility of the conceptions framework for describing prospective elementary teachers' conceptions of multidigit number. The report further contributes a framework for replication of mathematics education research adapted from the field of psychology.

Effects of catgut-embedding acupuncture technique on nitric oxide levels and blood pressure in patients with essential hypertension

NASA Astrophysics Data System (ADS)

Suhana; Srilestari, A.; Marbun, M. B. H.; Mihardja, H.

2017-08-01

Hypertension is common a health problem and its prevalence in Indonesia is quite high (31.7%). Catgut embedding—an acupuncture technique—is known to reduce blood pressure; however, no study has confirmed the underlying mechanism. This study examines the effect of catgut embedding on serum nitric oxide (NO) concentration and blood pressure in patients with essential hypertension. Forty hypertension patients were randomly assigned to two groups: the control group received anti-hypertensive drugs whereas the case group received anti-hypertensive drugs and catgut embedding. Results showed a statistically significant mean difference in NO concentration (p < 0.05) and statistically and clinically significant mean difference in systolic and diastolic blood pressure between the two groups (p < 0.05). The results confirm that catgut embedding can influence serum NO concentration and blood pressure in essential hypertension patients.

A Structured End-of-Life Curriculum for Neonatal-Perinatal Postdoctoral Fellows.

PubMed

Harris, Leslie L; Placencia, Frank X; Arnold, Jennifer L; Minard, Charles G; Harris, Toi B; Haidet, Paul M

2015-05-01

Death in tertiary care neonatal intensive care units is a common occurrence. Despite recent advances in pediatric palliative education, evidence indicates that physicians are poorly prepared to care for dying infants and their families. Numerous organizations recommend increased training in palliative and end-of-life care for pediatric physicians. The purpose of this study is to develop a structured end-of-life curriculum for neonatal-perinatal postdoctoral fellows based on previously established principles and curricular guidelines on end-of-life care in the pediatric setting. Results demonstrate statistically significant curriculum effectiveness in increasing fellow knowledge regarding patient qualification for comfort care and withdrawal of support (P = .03). Although not statistically significant, results suggest the curriculum may have improved fellows' knowledge of appropriate end-of-life medical management, comfort with addressing the family, and patient pain assessment and control. © The Author(s) 2014.

Rainfall statistics, stationarity, and climate change.

PubMed

Sun, Fubao; Roderick, Michael L; Farquhar, Graham D

2018-03-06

There is a growing research interest in the detection of changes in hydrologic and climatic time series. Stationarity can be assessed using the autocorrelation function, but this is not yet common practice in hydrology and climate. Here, we use a global land-based gridded annual precipitation (hereafter P ) database (1940-2009) and find that the lag 1 autocorrelation coefficient is statistically significant at around 14% of the global land surface, implying nonstationary behavior (90% confidence). In contrast, around 76% of the global land surface shows little or no change, implying stationary behavior. We use these results to assess change in the observed P over the most recent decade of the database. We find that the changes for most (84%) grid boxes are within the plausible bounds of no significant change at the 90% CI. The results emphasize the importance of adequately accounting for natural variability when assessing change. Copyright © 2018 the Author(s). Published by PNAS.

Rainfall statistics, stationarity, and climate change

NASA Astrophysics Data System (ADS)

Sun, Fubao; Roderick, Michael L.; Farquhar, Graham D.

2018-03-01

There is a growing research interest in the detection of changes in hydrologic and climatic time series. Stationarity can be assessed using the autocorrelation function, but this is not yet common practice in hydrology and climate. Here, we use a global land-based gridded annual precipitation (hereafter P) database (1940–2009) and find that the lag 1 autocorrelation coefficient is statistically significant at around 14% of the global land surface, implying nonstationary behavior (90% confidence). In contrast, around 76% of the global land surface shows little or no change, implying stationary behavior. We use these results to assess change in the observed P over the most recent decade of the database. We find that the changes for most (84%) grid boxes are within the plausible bounds of no significant change at the 90% CI. The results emphasize the importance of adequately accounting for natural variability when assessing change.

Paroxysmal atrial fibrillation prediction method with shorter HRV sequences.

PubMed

Boon, K H; Khalil-Hani, M; Malarvili, M B; Sia, C W

2016-10-01

This paper proposes a method that predicts the onset of paroxysmal atrial fibrillation (PAF), using heart rate variability (HRV) segments that are shorter than those applied in existing methods, while maintaining good prediction accuracy. PAF is a common cardiac arrhythmia that increases the health risk of a patient, and the development of an accurate predictor of the onset of PAF is clinical important because it increases the possibility to stabilize (electrically) and prevent the onset of atrial arrhythmias with different pacing techniques. We investigate the effect of HRV features extracted from different lengths of HRV segments prior to PAF onset with the proposed PAF prediction method. The pre-processing stage of the predictor includes QRS detection, HRV quantification and ectopic beat correction. Time-domain, frequency-domain, non-linear and bispectrum features are then extracted from the quantified HRV. In the feature selection, the HRV feature set and classifier parameters are optimized simultaneously using an optimization procedure based on genetic algorithm (GA). Both full feature set and statistically significant feature subset are optimized by GA respectively. For the statistically significant feature subset, Mann-Whitney U test is used to filter non-statistical significance features that cannot pass the statistical test at 20% significant level. The final stage of our predictor is the classifier that is based on support vector machine (SVM). A 10-fold cross-validation is applied in performance evaluation, and the proposed method achieves 79.3% prediction accuracy using 15-minutes HRV segment. This accuracy is comparable to that achieved by existing methods that use 30-minutes HRV segments, most of which achieves accuracy of around 80%. More importantly, our method significantly outperforms those that applied segments shorter than 30 minutes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The effect of subacromial injections of autologous conditioned plasma versus cortisone for the treatment of symptomatic partial rotator cuff tears.

PubMed

von Wehren, Lutz; Blanke, Fabian; Todorov, Atanas; Heisterbach, Patricia; Sailer, Jannis; Majewski, Martin

2016-12-01

Rotator cuff tears are one of the most common causes of shoulder malfunction and pain, which lead to a significant reduction in the quality of life. This present study investigated the effects of subacromial platelet-rich plasma injections [i.e. autologous conditioned plasma (ACP) injections] as compared to standard subacromial cortisone injection therapy in 50 patients with partial rotator cuff tears. Before injection, and 6 weeks, 12 weeks and 6 months thereafter, the patients were assessed by the Constant-Murley score (CMS), the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), the simple shoulder test (SST) and a pain visual analogue scale (VAS). An MRI was also performed before and 6 months after injection. Both patient groups had statistically significant better shoulder score outcomes over time. ASES, SST and CMS outcomes after 12 versus 6 weeks were better in the ACP group as compared to the cortisone group. VAS, ASES and CMS outcomes after 12 weeks versus baseline in the ACP group were better as compared to the cortisone group. There was a statistically significant difference between ACP group and cortisone group 12 weeks after injection regarding VAS, ASES, SST and CMS in favour of the ACP group. The MRI showed an improvement in grade of tendinopathy in both groups, however, without statistically significant differences between the two groups. Compared with cortisone injections, ACP injections show earlier benefit as compared to cortisone injections although a statistically significant difference after 6 months could not be found. Therefore, subacromial ACP injections are a good alternative to subacromial cortisone injections, especially in patients with contraindication to cortisone. Therapeutic study, Level III.

Evaluation of efficacy of a bioresorbable membrane in the treatment of oral lichen planus

PubMed Central

Kapoor, Anoop; Sikri, Poonam; Grover, Vishakha; Malhotra, Ranjan; Sachdeva, Sonia

2014-01-01

Background: Gingival involvement is commonly seen in lichen planus, a chronic mucocutaneous inflammatory condition of the stratified squamous epithelia. It is often painful and may undergo malignant transformation and thus warrants early diagnosis and prompt treatment. The aim of this study is to evaluate the use of a bioresorbable membrane (Polyglactin 910) in the management of erosive lichen planus of gingiva. Materials and Methods: A split-mouth randomized controlled trial was carried out. Fifteen patients with identical bilateral lesions of lichen planus on gingiva were included in the study. Three parameters were selected for the clinical assessment of gingival lesions: Surface texture, color, and burning sensation. After complete oral prophylaxis, an excisional biopsy procedure was carried out for lesions on both sides, but on the experimental side, the biopsy procedure was combined with placement of the bioresorbable membrane. The statistical significance of intergroup differences in measurements was tested by using an independent sample t-test. A two-tailed P-value less than 0.05 was considered as statistically significant. Results: Intragroup comparisons revealed a statistically significant difference between mean value of grades at 6, 12, and 24 weeks in both groups for the surface texture, color, and burning sensation of gingiva, respectively. For intergroup comparison of change in surface texture, color, and burning sensation of gingiva between group A and group B, differences were statistically nonsignificant. Conclusion: Surgical management of the lesion accomplished significant improvement of lesion with no significant additional clinical benefits with the application of bioresorbable membrane. Worsening of baseline scores was not observed in any case at the end of the study. PMID:25097651

Misconceptions of the p-value among Chilean and Italian Academic Psychologists

PubMed Central

Badenes-Ribera, Laura; Frias-Navarro, Dolores; Iotti, Bryan; Bonilla-Campos, Amparo; Longobardi, Claudio

2016-01-01

Common misconceptions of p-values are based on certain beliefs and attributions about the significance of the results. Thus, they affect the professionals' decisions and jeopardize the quality of interventions and the accumulation of valid scientific knowledge. We conducted a survey on 164 academic psychologists (134 Italian, 30 Chilean) questioned on this topic. Our findings are consistent with previous research and suggest that some participants do not know how to correctly interpret p-values. The inverse probability fallacy presents the greatest comprehension problems, followed by the replication fallacy. These results highlight the importance of the statistical re-education of researchers. Recommendations for improving statistical cognition are proposed. PMID:27602007

Multivariate two-part statistics for analysis of correlated mass spectrometry data from multiple biological specimens.

PubMed

Taylor, Sandra L; Ruhaak, L Renee; Weiss, Robert H; Kelly, Karen; Kim, Kyoungmi

2017-01-01

High through-put mass spectrometry (MS) is now being used to profile small molecular compounds across multiple biological sample types from the same subjects with the goal of leveraging information across biospecimens. Multivariate statistical methods that combine information from all biospecimens could be more powerful than the usual univariate analyses. However, missing values are common in MS data and imputation can impact between-biospecimen correlation and multivariate analysis results. We propose two multivariate two-part statistics that accommodate missing values and combine data from all biospecimens to identify differentially regulated compounds. Statistical significance is determined using a multivariate permutation null distribution. Relative to univariate tests, the multivariate procedures detected more significant compounds in three biological datasets. In a simulation study, we showed that multi-biospecimen testing procedures were more powerful than single-biospecimen methods when compounds are differentially regulated in multiple biospecimens but univariate methods can be more powerful if compounds are differentially regulated in only one biospecimen. We provide R functions to implement and illustrate our method as supplementary information CONTACT: sltaylor@ucdavis.eduSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Common mental disorder and its association with academic performance among Debre Berhan University students, Ethiopia.

PubMed

Haile, Yohannes Gebreegziabhere; Alemu, Sisay Mulugeta; Habtewold, Tesfa Dejenie

2017-01-01

Common mental disorder (CMD) is prevalent in industrialized and non-industrialized countries. The prevalence of CMD among university students was 28.8-44.7% and attributed to several risk factors, such as schooling. The aim of this study was to assess the prevalence and risk factors of CMD. In addition, the association between CMD and academic performance was tested. Institution based cross-sectional study was conducted with 422 students at Debre Berhan university from March to April 2015. CMD was the primary outcome variable whereas academic performance was the secondary outcome variable. Kessler psychological distress (K10) scale was used to assess CMD. Bivariate and multiple logistic regression analysis were performed for modeling the primary outcome variable; independent samples T test and linear regression analysis were carried out for modeling the secondary outcome variable. The strength of association was interpreted using odds ratio and regression coefficient (β) and decision on statistical significance was made at a p value of 0.05. Data were entered using EPI-data version 3.1 software and analyzed using the Statistical Package for the Social Sciences (SPSS) version 20.01 software. The prevalence of CMD was 63.1%. Field of study (p = 0.008, OR = 0.2, 95% CI 0.04-0.61), worshiping (p = 0.04, OR = 1.8, 95% CI 1.02-3.35), insomnia (p < 0.001, OR = 3.8, 95% CI 2.21-6.57), alcohol drinking (p = 0.006, OR = 2.7, 95% CI 1.33-5.66), and headache (p = 0.02, OR = 2.1, 95% CI 1.10-3.86) were identified risk factors for CMD. The mean cumulative grade point average of students with CMD was lower by 0.02 compared to those without CMD, but not statistically significant (p = 0.70, β = -0.02, 95% CI -0.15 to 0.10). CMD explained only 0.8% (r 2  = 0.008) of the difference in academic performance between students. At least three out of five students fulfilled CMD diagnostic criteria. The statistically significant risk factors were field of study, worshiping, insomnia, alcohol drinking, and headache. Moreover, there was no statistically significant association between CMD and academic performance. Undertaking integrated evidence-based intervention focusing on students with poor sleep quality, poor physical health, and who drink alcohol is essential if the present finding confirmed by a longitudinal study.

Structurally Sound Statistics Instruction

ERIC Educational Resources Information Center

Casey, Stephanie A.; Bostic, Jonathan D.

2016-01-01

The Common Core's Standards for Mathematical Practice (SMP) call for all K-grade 12 students to develop expertise in the processes and proficiencies of doing mathematics. However, the Common Core State Standards for Mathematics (CCSSM) (CCSSI 2010) as a whole addresses students' learning of not only mathematics but also statistics. This situation…

A Comparison of Two-Group Classification Methods

ERIC Educational Resources Information Center

Holden, Jocelyn E.; Finch, W. Holmes; Kelley, Ken

2011-01-01

The statistical classification of "N" individuals into "G" mutually exclusive groups when the actual group membership is unknown is common in the social and behavioral sciences. The results of such classification methods often have important consequences. Among the most common methods of statistical classification are linear discriminant analysis,…

Comparative Evaluation of Marginal Adaptation of BiodentineTM and Other Commonly Used Root End Filling Materials-An Invitro Study

PubMed Central

P.V., Ravichandra; Vemisetty, Harikumar; K., Deepthi; Reddy S, Jayaprada; D., Ramkiran; Krishna M., Jaya Nagendra; Malathi, Gita

2014-01-01

Aim: The purpose of this investigation was to evaluate the marginal adaptation of three root-end filling materials Glass ionomer cement, Mineral trioxide aggregate and BiodentineTM. Methodology: Thirty human single-rooted teeth were resected 3 mm from the apex. Root-end cavities were then prepared using an ultrasonic tip and filled with one of the following materials Glass ionomer cement (GIC), Mineral trioxide aggregate (MTA) and a bioactive cement BiodentineTM. The apical portions of the roots were then sectioned to obtain three 1 mm thick transversal sections. Confocal laser scanning microscopy (CLSM) was used to determine area of gaps and adaptation of the root-end filling materials with the dentin. The Post hoc test, a multiple comparison test was used for statistical data analysis. Results: Statistical analysis showed lowest marginal gaps (11143.42±967.753m2) and good marginal adaptation with BiodentineTM followed by MTA (22300.97±3068.883m2) and highest marginal gaps with GIC (33388.17±12155.903m2) which were statistically significant (p<0.0001). Conclusion: A new root end filling material BiodentineTM showed better marginal adaptation than commonly used root end filling materials PMID:24783148

ENT care of children and adolescents in the Brazilian public healthy system in three different municipalities.

PubMed

T-Ping, Cheng; Weckx, Luc Louis Maurice

2008-01-01

The data base of ENT care in the Brazilian public health system (Sistema Unico de Saude - SUS) will help organize public health programs. The following items were investigated in patients aged up to 17 years attended in public health system outpatient units in the city of Mariana, in the ENT screening unit, UNIFESP-EPM, and in CISMISEL: 1) The main otorhinolaryngological diagnoses; 2) The most frequently required exams, drugs, and surgical procedures and their indications; 3) The jobs of parents; the number of siblings; and 4) A statistical analysis and comparison of data in each location. We undertook a prospective study and a statistical analysis of variables that were gathered during the first visit. The age, the parents' salary, the number of siblings aged below 18 years, the presence of rhinitis, ears diseases, the exams, drugs and otological surgeries that were indicated were all statistically significant. The most common diagnosis was mouth breathing. The most common surgery was adenotonsillectomy. The most frequently requested exam was a lateral cranial radiograph. The number of unemployed parents, their poor salaries, and the number of siblings make it difficult for these patients to be treated in any facility other than the public heath system.

Photodynamic diagnosis in upper urinary tract urothelial carcinoma: A systematic review.

PubMed

Osman, Elsawi; Alnaib, Ziad; Kumar, Nitya

2017-06-01

To assess the diagnostic accuracy and safety of photodynamic diagnosis (PDD) in upper urinary tract urothelial carcinoma (UUTUC). A systematic literature search was conducted. Included studies were assessed for the risks of bias and quality using appropriate tools. Dedicated data extraction forms were used. Diagnostic accuracy in terms of sensitivity and specificity were quoted whenever provided by individual studies. A combined toxicity profile of 5-aminolevulinic acid (5ALA) was given after reviewing individual studies. In all, 17 studies were identified. After screening seven studies were included involving a total of 194 patients. None of the studies were randomised. All the available studies were of low-to-moderate quality. The largest available study, with 106 patients, reported a sensitivity of 95.8% and 53.5% for PDD and white-light (WL) ureterorenoscopy (URS) respectively, with a statistically significant difference. The specificity was 96.6% for PDD and 95.2% for WL-URS with no statistical significance. PDD showed better ability in detecting carcinoma in situ and dysplasia. One study compared PDD to computed tomography urogram (CTU) and found PDD to have better sensitivity and statistically significantly better specificity. 5ALA-associated toxicity was minor in nature and hypotension was the most common adverse event. PDD in UUTUC appears to be more accurate than WL-URS and CTU, with no significant toxicity. Larger scale randomised trials are needed.

Prognostic significance of MCM 2 and Ki-67 in neuroblastic tumors in children.

PubMed

Lewandowska, Magdalena; Taran, Katarzyna; Sitkiewicz, Anna; Andrzejewska, Ewa

2015-12-02

Neuroblastic tumors can be characterized by three features: spontaneous regression, maturation and aggressive proliferation. The most common and routinely used method of assessing tumor cell proliferation is to determine the Ki-67 index in the tumor tissue. Despite numerous studies, neuroblastoma biology is not fully understood, which makes treatment results unsatisfactory. MCM 2 is a potential prognostic factor in the neuroblastoma group. The study is based on retrospective analysis of 35 patients treated for neuroblastic tumors in the Department of Pediatric Surgery and Oncology of the Medical University of Lodz, during the period 2001-2011. The material comprised tissues of 16 tumors excised during the operation and 19 biopsy specimens. Immunohistochemical examinations were performed with immunoperoxidase using mouse monoclonal anti-MCM 2 and anti-Ki-67 antibodies. We observed that MCM 2 expression ranged from 2% to 98% and the Ki-67 index ranged from 0 to 95%. There was a statistically significant correlation between expression of MCM 2 and the value of the Ki-67 index and a correlation close to statistical significance between expression of MCM 2 and unfavorable histopathology. There was no statistical relationship between expression of MCM 2 and age over 1 year and N-myc amplification. The presented research shows that MCM 2 may have prognostic significance in neuroblastic pediatric tumors and as a potential prognostic factor could be the starting point of new individualized therapy.

Cognitive syndromes after the first stroke.

PubMed

Salihović, Denisa; Smajlović, Dževdet; Mijajlović, Milija; Zoletić, Emina; Ibrahimagić, Omer Ć

2018-05-19

The aim of this study is to determine impairments of certain cognitive functions in certain vascular cognitive syndromes and to identify predictors of dementia. One-year prospective study included 275 patients, who were hospitalized at the Department of Neurology Tuzla and therefore fulfilled certain criteria. Patients were divided into following subgroups of vascular cognitive impairment (VCI): dementia of strategic infarct (DSI), cortical dementia (CD), sub cortical dementia (SCD), hemorrhagic dementia (HD), and patients without dementia. Each of the patients underwent the clinical examination and scoring with appropriate measurement scales. Some of the types of VCI were verified in 190 (69%) patients, and the most common was SCD (58%). There was statistically significant connection between the level of intelligence and occurrence of VCI in patients after stroke (p < 0.001). We found significant connection between occurrence of dementia and impairment in narrative memory, numerical memory, visual perceptive, and visual constructive functions in patients with dementia compared with non-demented (p = 0.0001). The executive functions were statistically impaired in patients with CD (p = 0.004) and SCD (p < 0.001). Patients without dementia have significantly better quality of life than the demented ones (p < 0.0001). The algorithm "tree of decision" can help us in the prediction of dementia based on the impairment of certain cognitive functions. Vascular cognitive syndromes are common after stroke. Some of the cognitive functions are significantly impaired in patients with dementia. Impairment of the certain cognitive functions can help in predicting the onset of dementia. Patients without dementia have better quality of life.

Renal dysfunction in liver cirrhosis and its correlation with Child-Pugh score and MELD score

NASA Astrophysics Data System (ADS)

Siregar, G. A.; Gurning, M.

2018-03-01

Renal dysfunction (RD) is a serious and common complication in a patient with liver cirrhosis. It provides a poor prognosis. The aim of our study was to evaluate the renal function in liver cirrhosis, also to determine the correlation with the graduation of liver disease assessed by Child-Pugh Score (CPS) and MELD score. This was a cross-sectional study included patients with liver cirrhosis admitted to Adam Malik Hospital Medan in June - August 2016. We divided them into two groups as not having renal dysfunction (serum creatinine < 1.5 mg/dL) and having renal dysfunction (serum creatinine ≤ 1.5 mg/dL). For the processing of data, SPSS 22.0 was used. Statistical methods used: Chi-square, Fisher exact, one way ANOVA, Kruskal Wallis test and Pearson coefficient of correlation. The level of significance was p<0.05. 55 patients with presented with renal dysfunction were 16 (29.1 %). There was statistically significant inverse correlation between GFR and CPS (r = -0.308), GFR and MELD score (r = -0.278). There was a statistically significant correlation between creatinine and MELD score (r = 0.359), creatinine and CPS (r = 0.382). The increase of the degree of liver damage is related to the increase of renal dysfunction.

Piloting a Sex-Specific, Technology-Enhanced, Active Learning Intervention for Stroke Prevention in Women.

PubMed

Dirickson, Amanda; Stutzman, Sonja E; Alberts, Mark J; Novakovic, Roberta L; Stowe, Ann M; Beal, Claudia C; Goldberg, Mark P; Olson, DaiWai M

2017-12-01

Recent studies reveal deficiencies in stroke awareness and knowledge of risk factors among women. Existing stroke education interventions may not address common and sex-specific risk factors in the population with the highest stroke-related rate of mortality. This pilot study assessed the efficacy of a technology-enhanced, sex-specific educational program ("SISTERS") for women's knowledge of stroke. This was an experimental pretest-posttest design. The sample consisted of 150 women (mean age, 55 years) with at least 1 stroke risk factor. Participants were randomized to either the intervention (n = 75) or control (n = 75) group. Data were collected at baseline and at a 2-week posttest. There was no statistically significant difference in mean knowledge score (P = .67), mean confidence score (P = .77), or mean accuracy score (P = .75) between the intervention and control groups at posttest. Regression analysis revealed that older age was associated with lower knowledge scores (P < .001) and lower confidence scores (P < .001). After controlling for age, the SISTERS program was associated with a statistically significant difference in knowledge (P < .001) and confidence (P < .001). Although no change occurred overall, after controlling for age, there was a statistically significant benefit. Older women may have less comfort with technology and require consideration for cognitive differences.

Ocular surface culture changes in patients after septoplasty.

PubMed

Ozkiriş, Mahmut; Kapusuz Gencer, Zeliha; Kader, Ciğdem; Saydam, Levent

2014-01-01

To investigate the interrelationships between pre- and postoperative microbiological changes by taking samples from both eyes of 40 patients who underwent septoplasty due to septal deviation. Forty patients diagnosed with septal deviation who underwent a septoplasty operation under general anesthesia were enrolled in this study. The study was conducted on 40 patients who met the inclusion criteria and attended follow-up visits. One day before the operation and 48 h after the operation, cultures were taken individually from the conjunctivas and puncta of both eyes and sent to the microbiology laboratory. Patients who were candidates for nasal surgery due to their symptoms and clinical examination results were randomly selected and 40 of these completed the study. No statistically significant differences in bacterial growth were observed between the eyes before the operation (P > 0.05). There were, however, statistically significant differences between the eyes in terms of bacterial growth in the postoperative period (P < 0.05). Pathogenic bacterial cultures were grown in 47 eyes in the postoperative period, and this finding was statistically significant. In the eye cultures, the most commonly isolated pathogens were S. epidermidis, and S. aureus. Although the indicated microorganisms isolated from the patient groups were grown in cultures, there were neither clinical symptoms nor signs related to ocular infections.

Evaluating the statistical performance of less applied algorithms in classification of worldview-3 imagery data in an urbanized landscape

NASA Astrophysics Data System (ADS)

Ranaie, Mehrdad; Soffianian, Alireza; Pourmanafi, Saeid; Mirghaffari, Noorollah; Tarkesh, Mostafa

2018-03-01

In recent decade, analyzing the remotely sensed imagery is considered as one of the most common and widely used procedures in the environmental studies. In this case, supervised image classification techniques play a central role. Hence, taking a high resolution Worldview-3 over a mixed urbanized landscape in Iran, three less applied image classification methods including Bagged CART, Stochastic gradient boosting model and Neural network with feature extraction were tested and compared with two prevalent methods: random forest and support vector machine with linear kernel. To do so, each method was run ten time and three validation techniques was used to estimate the accuracy statistics consist of cross validation, independent validation and validation with total of train data. Moreover, using ANOVA and Tukey test, statistical difference significance between the classification methods was significantly surveyed. In general, the results showed that random forest with marginal difference compared to Bagged CART and stochastic gradient boosting model is the best performing method whilst based on independent validation there was no significant difference between the performances of classification methods. It should be finally noted that neural network with feature extraction and linear support vector machine had better processing speed than other.

Neck-upper extremity musculoskeletal disorders among workers in the telecommunications company at Mansoura City.

PubMed

El-Bestar, Sohair Fouad; El-Mitwalli, Ashraf Abdel-Moniem; Khashaba, Eman Omar

2011-01-01

This study was to determine the prevalence and work-related risk factors of neck-upper extremity musculoskeletal disorders (MSDs) among video display terminal (VDT) users. A comparative cross-sectional study was conducted; there were 60 VDT users and 35 controls. The participants filled in a structured questionnaire, had electrophysiological tests and an X-ray of the neck. The prevalence of MSDs was higher (28.3%) among VDTs users compared to controls (14.3%) with no statistically significant difference. The prevalence of cervical disorders with or without radiculopathy (18.3%) was the most common disorder followed by carpal tunnel syndrome (6.6%). The mean (SD) age of MSD cases (51 ± 7.2 years) was statistically significantly higher than of the controls (42.8 ± 9). Physical exposure to prolonged static posture (OR: 6.9; 95% CI: 0.83-57.9), awkward posture (OR: 5.5; 95% CI: 0.6-46.4) and repetitive movements (OR: 5.5; 95% CI: 0.65-46.4) increased risk of MSDs with a statistically significant difference for static posture only (p < .05). VDT users experienced more job dissatisfaction, work-overload and limited social support from supervisors and colleagues. VDT use did not increase the risk of neck-upper extremity MSDs. The risk increased with older age and static posture.

Common errors in textbook descriptions of muscle fiber size in nontrained humans.

PubMed

Chalmers, Gordon R; Row, Brandi S

2011-09-01

Exercise science and human anatomy and physiology textbooks commonly report that type IIB muscle fibers have the largest cross-sectional area of the three fiber types. These descriptions of muscle fiber sizes do not match with the research literature examining muscle fibers in young adult nontrained humans. For men, most commonly type IIA fibers were significantly larger than other fiber types (six out of 10 cases across six different muscles). For women, either type I, or both I and IIA muscle fibers were usually significantly the largest (five out of six cases across four different muscles). In none of these reports were type IIB fibers significantly larger than both other fiber types. In 27 studies that did not include statistical comparisons of mean fiber sizes across fiber types, in no cases were type IIB or fast glycolytic fibers larger than both type I and IIA, or slow oxidative and fast oxidative glycolytic fibers. The likely reason for mistakes in textbook descriptions of human muscle fiber sizes is that animal data were presented without being labeled as such, and without any warning that there are interspecies differences in muscle fiber properties. Correct knowledge of muscle fiber sizes may facilitate interpreting training and aging adaptations.

Pig brain stereotaxic standard space: mapping of cerebral blood flow normative values and effect of MPTP-lesioning.

PubMed

Andersen, Flemming; Watanabe, Hideaki; Bjarkam, Carsten; Danielsen, Erik H; Cumming, Paul

2005-07-15

The analysis of physiological processes in brain by position emission tomography (PET) is facilitated when images are spatially normalized to a standard coordinate system. Thus, PET activation studies of human brain frequently employ the common stereotaxic coordinates of Talairach. We have developed an analogous stereotaxic coordinate system for the brain of the Gottingen miniature pig, based on automatic co-registration of magnetic resonance (MR) images obtained in 22 male pigs. The origin of the pig brain stereotaxic space (0, 0, 0) was arbitrarily placed in the centroid of the pineal gland as identified on the average MRI template. The orthogonal planes were imposed using the line between stereotaxic zero and the optic chiasm. A series of mean MR images in the coronal, sagittal and horizontal planes were generated. To test the utility of the common coordinate system for functional imaging studies of minipig brain, we calculated cerebral blood flow (CBF) maps from normal minipigs and from minipigs with a syndrome of parkisonism induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-poisoning. These maps were transformed from the native space into the common stereotaxic space. After global normalization of these maps, an undirected search for differences between the groups was then performed using statistical parametric mapping. Using this method, we detected a statistically significant focal increase in CBF in the left cerebellum of the MPTP-lesioned group. We expect the present approach to be of general use in the statistical parametric mapping of CBF and other physiological parameters in living pig brain.

Things we still haven't learned (so far).

PubMed

Ivarsson, Andreas; Andersen, Mark B; Stenling, Andreas; Johnson, Urban; Lindwall, Magnus

2015-08-01

Null hypothesis significance testing (NHST) is like an immortal horse that some researchers have been trying to beat to death for over 50 years but without any success. In this article we discuss the flaws in NHST, the historical background in relation to both Fisher's and Neyman and Pearson's statistical ideas, the common misunderstandings of what p < .05 actually means, and the 2010 APA publication manual's clear, but most often ignored, instructions to report effect sizes and to interpret what they all mean in the real world. In addition, we discuss how Bayesian statistics can be used to overcome some of the problems with NHST. We then analyze quantitative articles published over the past three years (2012-2014) in two top-rated sport and exercise psychology journals to determine whether we have learned what we should have learned decades ago about our use and meaningful interpretations of statistics.

A bibliometric analysis of statistical terms used in American Physical Therapy Association journals (2011-2012): evidence for educating physical therapists.

PubMed

Tilson, Julie K; Marshall, Katie; Tam, Jodi J; Fetters, Linda

2016-04-22

A primary barrier to the implementation of evidence based practice (EBP) in physical therapy is therapists' limited ability to understand and interpret statistics. Physical therapists demonstrate limited skills and report low self-efficacy for interpreting results of statistical procedures. While standards for physical therapist education include statistics, little empirical evidence is available to inform what should constitute such curricula. The purpose of this study was to conduct a census of the statistical terms and study designs used in physical therapy literature and to use the results to make recommendations for curricular development in physical therapist education. We conducted a bibliometric analysis of 14 peer-reviewed journals associated with the American Physical Therapy Association over 12 months (Oct 2011-Sept 2012). Trained raters recorded every statistical term appearing in identified systematic reviews, primary research reports, and case series and case reports. Investigator-reported study design was also recorded. Terms representing the same statistical test or concept were combined into a single, representative term. Cumulative percentage was used to identify the most common representative statistical terms. Common representative terms were organized into eight categories to inform curricular design. Of 485 articles reviewed, 391 met the inclusion criteria. These 391 articles used 532 different terms which were combined into 321 representative terms; 13.1 (sd = 8.0) terms per article. Eighty-one representative terms constituted 90% of all representative term occurrences. Of the remaining 240 representative terms, 105 (44%) were used in only one article. The most common study design was prospective cohort (32.5%). Physical therapy literature contains a large number of statistical terms and concepts for readers to navigate. However, in the year sampled, 81 representative terms accounted for 90% of all occurrences. These "common representative terms" can be used to inform curricula to promote physical therapists' skills, competency, and confidence in interpreting statistics in their professional literature. We make specific recommendations for curriculum development informed by our findings.

Comparing fist size to heart size is not a viable technique to assess cardiomegaly.

PubMed

Ampanozi, Garyfalia; Krinke, Eileen; Laberke, Patrick; Schweitzer, Wolf; Thali, Michael J; Ebert, Lars C

2018-05-07

Several medical textbooks state that a human heart is approximately the size of that person's fist. Stating that a heart has the size of the corpse's fist is thought to signify that the heart size is normal. We formulate two hypotheses that are tested in this article. First, we hypothesize that in cases without cardiomegaly, volumes of the hand and the heart are not significantly different. Second, we hypothesize that in cases of cardiomegaly, the heart volume statistically significantly exceeds that of the hand. We retrospectively reviewed 130 consecutive postmortem computed tomography datasets from the BLINDED starting from 01/01/2013, covering a period of approximately 3 months. Hands and hearts were segmented and their volumes estimated. We obtained the following information from the postmortem examination reports: age, sex, body length and weight, heart weight, cardiomegaly, and cause of death. When exploring the correlation between mean hand volume and heart volume, only in the group of the females with cardiomegaly (N=8) could a positive, statistically significant correlation be ascertained (Pearson correlation coefficient 0.753, P=.031). In this study, we demonstrated that the commonly used idea that a heart larger than the fist of a patient suggests cardiomegaly might be incorrect. Because this perception is commonly used in autopsy reports, it might lead to avoidable errors. Until further studies confirm this hypothesis, this informal measurement should no longer be taught or used. Copyright © 2018 Elsevier Inc. All rights reserved.

Antimicrobial properties of Cocos nucifera (coconut) husk: An extrapolation to oral health.

PubMed

Jose, Maji; Cyriac, Maria B; Pai, Vidya; Varghese, Ipe; Shantaram, Manjula

2014-07-01

Brushing the teeth with fibrous husk of Cocos nucifera (coconut) is a common oral hygiene practice among people of rural areas of South India. However, the probable antimicrobial properties of this plant material against common oral pathogens have not been proved scientifically. Therefore, the present study was designed. Alcoholic extract of the husk of Cocos nucifera was prepared and the antimicrobial properties against common oral pathogens like cariogenic bacteria, periodontal pathogens, and candidal organisms were performed by the Agar Well Diffusion Method. The results obtained were then subjected to statistical analysis using One-Way Analysis of Variance (ANOVA) and the Tukey's Honestly Significant Difference (HSD). The alcoholic extract of Cocos nucifera showed a significant concentration-dependent antimicrobial activity, expressed as a zone of inhibition with respect to all tested organisms except Actinomyces species. The inhibitory effect was more significant, with a majority of cariogenic organisms and Candida, with a zone of inhibition ranging from 4.6 mm to 16.3 mm. However, the effect was lesser with Cocos nucifera compared to chlorhexidine. Minimum inhibitory concentration (MIC) ranged from 50 mg/ml to 75 mg/ml. Cocos nucifera has a significant inhibitory action against common oral pathogens, indicating the presence of highly effective antimicrobial compounds. Therefore, it is proved that its use can contribute to oral health to a great extent. Identification of these active compounds provides the scope for incorporating it into a modern oral care system, so as to control oral diseases.

Light Treatment for Neuropsychiatric Behaviors in Alzheimer’s Disease

PubMed Central

Dowling, Glenna A.; Graf, Carla; Hubbard, Erin M.; Luxenberg, Jay S.

2008-01-01

Neuropsychiatric behaviors are common in people with Alzheimer’s disease (AD) and make both professional and lay caregiving difficult. Light therapy has been somewhat successful in ameliorating disruptive behaviors. This randomized trial tested the effects of morning or afternoon bright light exposure compared with usual indoor light on the presence, frequency, severity, and occupational disruptiveness of neuropsychiatric behaviors in nursing home residents with AD. Light was administered for 1 hr daily (Monday–Friday) for 10 weeks. The Neuropsychiatric Inventory–Nursing Home was used to assess behavior at baseline and end of the intervention. Analyses revealed statistically significant differences between groups on agitation/aggression, depression/dysphoria, aberrant motor behavior, and appetite/eating disorders. The magnitude of change was small and may not represent clinically significant findings. Agitation/aggression and nighttime behaviors commonly occurred and were highly correlated with occupational disruptiveness. Interventions that decrease the presence and/or severity of neuropsychiatric behaviors have the potential to significantly decrease caregiver burden. PMID:17596638

The magnitude of variability produced by methods used to estimate annual stormwater contaminant loads for highly urbanised catchments.

PubMed

Beck, H J; Birch, G F

2013-06-01

Stormwater contaminant loading estimates using event mean concentration (EMC), rainfall/runoff relationship calculations and computer modelling (Model of Urban Stormwater Infrastructure Conceptualisation--MUSIC) demonstrated high variability in common methods of water quality assessment. Predictions of metal, nutrient and total suspended solid loadings for three highly urbanised catchments in Sydney estuary, Australia, varied greatly within and amongst methods tested. EMC and rainfall/runoff relationship calculations produced similar estimates (within 1 SD) in a statistically significant number of trials; however, considerable variability within estimates (∼50 and ∼25 % relative standard deviation, respectively) questions the reliability of these methods. Likewise, upper and lower default inputs in a commonly used loading model (MUSIC) produced an extensive range of loading estimates (3.8-8.3 times above and 2.6-4.1 times below typical default inputs, respectively). Default and calibrated MUSIC simulations produced loading estimates that agreed with EMC and rainfall/runoff calculations in some trials (4-10 from 18); however, they were not frequent enough to statistically infer that these methods produced the same results. Great variance within and amongst mean annual loads estimated by common methods of water quality assessment has important ramifications for water quality managers requiring accurate estimates of the quantities and nature of contaminants requiring treatment.

Comparative trial of 5% dexpanthenol in water-in-oil formulation with 1% hydrocortisone ointment in the treatment of childhood atopic dermatitis: a pilot study.

PubMed

Udompataikul, Montree; Limpa-o-vart, Dipenn

2012-03-01

Atopic dermatitis (AD) is a common chronic relapsing disease particularly affecting children. The emollient used for protection of skin barrier function is the standard treatment for patients with AD. Currently, there is a growing interest in the use of nonsteroidal anti-inflammatory agents such as dexpanthenol (vitamin B5) as an alternative treatment. To compare the effectiveness of 5% dexpanthenol (DT) ointment with 1% hydrocortisone (HC) ointment in childhood AD therapy. Patients were treated topically with 5% DT ointment on the right side of the body and 1% HC ointment on the other side twice daily for 4 weeks. The clinical responses were evaluated by SCORAD (Scoring Atopic Dermatitis index) with statistical analysis using paired t-test. Of the 30 children enrolled, 26 completed the protocol; mean age was 7.19 years. The average baseline SCORAD score of the DT-treated side and the HC-treated side was 30.95 and 30.54, respectively. There was no statistically significant difference in SCORAD score reduction between the 2 agents. The edematous score of the HC-treated side exhibited faster resolution than that of the DT-treated side, with a statistically significant difference at week 1 and without a statistically significant difference at weeks 2 to 4. The lichenification response rate of HC treatment was more rapid than that of DT treatment; however, there was no statistical group difference. No adverse events were observed with either agent. The effectiveness of 5% DT ointment is equal to that of 1% HC ointment. DT ointment may be used as alternative treatment in mild to moderate childhood AD therapy.

Education and Labour Market Transitions in Young Adulthood. Culture, Tourism and the Centre for Education Statistics. Research Paper. Catalogue no. 81-595-M No. 075

ERIC Educational Resources Information Center

Shaienks, Danielle; Gluszynski, Tomasz

2009-01-01

Young adulthood is filled with major life events and pursuing higher education is one of the most common transitions. It is also the time when many young adults enter the labour market, move out of their parents' household and begin family formation. These significant events affect each other and impact the rest of their lives. Given the…

Statistical model specification and power: recommendations on the use of test-qualified pooling in analysis of experimental data

PubMed Central

Colegrave, Nick

2017-01-01

A common approach to the analysis of experimental data across much of the biological sciences is test-qualified pooling. Here non-significant terms are dropped from a statistical model, effectively pooling the variation associated with each removed term with the error term used to test hypotheses (or estimate effect sizes). This pooling is only carried out if statistical testing on the basis of applying that data to a previous more complicated model provides motivation for this model simplification; hence the pooling is test-qualified. In pooling, the researcher increases the degrees of freedom of the error term with the aim of increasing statistical power to test their hypotheses of interest. Despite this approach being widely adopted and explicitly recommended by some of the most widely cited statistical textbooks aimed at biologists, here we argue that (except in highly specialized circumstances that we can identify) the hoped-for improvement in statistical power will be small or non-existent, and there is likely to be much reduced reliability of the statistical procedures through deviation of type I error rates from nominal levels. We thus call for greatly reduced use of test-qualified pooling across experimental biology, more careful justification of any use that continues, and a different philosophy for initial selection of statistical models in the light of this change in procedure. PMID:28330912

Computational Analysis for Rocket-Based Combined-Cycle Systems During Rocket-Only Operation

NASA Technical Reports Server (NTRS)

Steffen, C. J., Jr.; Smith, T. D.; Yungster, S.; Keller, D. J.

2000-01-01

A series of Reynolds-averaged Navier-Stokes calculations were employed to study the performance of rocket-based combined-cycle systems operating in an all-rocket mode. This parametric series of calculations were executed within a statistical framework, commonly known as design of experiments. The parametric design space included four geometric and two flowfield variables set at three levels each, for a total of 729 possible combinations. A D-optimal design strategy was selected. It required that only 36 separate computational fluid dynamics (CFD) solutions be performed to develop a full response surface model, which quantified the linear, bilinear, and curvilinear effects of the six experimental variables. The axisymmetric, Reynolds-averaged Navier-Stokes simulations were executed with the NPARC v3.0 code. The response used in the statistical analysis was created from Isp efficiency data integrated from the 36 CFD simulations. The influence of turbulence modeling was analyzed by using both one- and two-equation models. Careful attention was also given to quantify the influence of mesh dependence, iterative convergence, and artificial viscosity upon the resulting statistical model. Thirteen statistically significant effects were observed to have an influence on rocket-based combined-cycle nozzle performance. It was apparent that the free-expansion process, directly downstream of the rocket nozzle, can influence the Isp efficiency. Numerical schlieren images and particle traces have been used to further understand the physical phenomena behind several of the statistically significant results.

Uterine Cancer Statistics

MedlinePlus

... Doing AMIGAS Stay Informed Cancer Home Uterine Cancer Statistics Language: English (US) Español (Spanish) Recommend on Facebook ... the most commonly diagnosed gynecologic cancer. U.S. Cancer Statistics Data Visualizations Tool The Data Visualizations tool makes ...

Relationship between Omnibus and Post-hoc Tests: An Investigation of performance of the F test in ANOVA.

PubMed

Chen, Tian; Xu, Manfei; Tu, Justin; Wang, Hongyue; Niu, Xiaohui

2018-02-25

Comparison of groups is a common statistical test in many biomedical and psychosocial research studies. When there are more than two groups, one first performs an omnibus test for an overall difference across the groups. If this null is rejected, one then proceeds to the next step of post-hoc pairwise group comparisons to determine sources of difference. Otherwise, one stops and declares no group difference. A common belief is that if the omnibus test is significant, there must exist at least two groups that are significantly different and vice versa. Thus, when the omnibus test is significant, but no post-hoc between-group comparison shows significant difference, one is bewildered at what is going on and wondering how to interpret the results. At the end of the spectrum, when the omnibus test is not significant, one wonders if all post-hoc tests will be non-significant as well so that stopping after a nonsignificant omnibus test will not lead to any missed opportunity of finding group difference. In this report, we investigate this perplexing phenomenon and discuss how to interpret such results.

Role of Laryngopharyngeal Reflux in Complications of Tonsillectomy in Pediatric Patients.

PubMed

Salturk, Ziya; Kumral, Tolgar Lutfi; Arslanoglu, Ahmet; Aydogdu, Imran; Yildirim, Guven; Berkiten, Guler; Uyar, Yavuz

2017-09-01

Tonsillectomy and tonsillectomy with adenoidectomy are among the most common surgical procedures in otolaryngology practice. Gastroesophageal reflux was identified as a risk factor for complications in tonsillectomy. This prospective study was designed to assess the role of reflux in the development of complications following tonsillectomy in pediatric patients. Children (n = 60) who underwent tonsillectomy with adenoidectomy were divided into two groups, i.e., the laryngopharyngeal reflux (LPR) group and control group. Patients with LPR were identified by reflux symptom index and reflux finding score. Pain, hemorrhage, fever, nausea, vomiting, fever, dehydration, infection, and pulmonary problems were evaluated post operatively. The mean lengths of hospital stay were 2.11 days in the reflux group and 1.05 days in the control group. The difference was statistically significant. Visual analogue scores of both groups were similar on day 1 but it was significantly higher on day 7 and 14 in LPR group. Nausea and vomiting rates were 11.1 and 9.5 % for the patients in the LPR group and the controls, respectively. The difference between the two groups was not significant. The mean fever was 37.6 °C in the reflux group and 37.3 °C in the controls, which were not significantly different. 19 % of the controls and 22 % of the LPR group patients were readmitted. This difference was not statistically significant. There were two cases of bleeding in the reflux group, while no bleeding occurred in the control group. This difference was significant statistically. LPR is a risk factor for complications following tonsillectomy.

Productive Information Foraging

NASA Technical Reports Server (NTRS)

Furlong, P. Michael; Dille, Michael

2016-01-01

This paper presents a new algorithm for autonomous on-line exploration in unknown environments. The objective of the algorithm is to free robot scientists from extensive preliminary site investigation while still being able to collect meaningful data. We simulate a common form of exploration task for an autonomous robot involving sampling the environment at various locations and compare performance with a simpler existing algorithm that is also denied global information. The result of the experiment shows that the new algorithm has a statistically significant improvement in performance with a significant effect size for a range of costs for taking sampling actions.

Botulinum toxin type-A (BOTOX) in the treatment of occipital neuralgia: a pilot study.

PubMed

Taylor, Martin; Silva, Sachin; Cottrell, Constance

2008-01-01

To determine the efficacy of occipital nerve blocks using reconstituted botulinum toxin type-A (BTX-A) in providing significant and prolonged pain relief in chronic occipital neuralgia. Occipital neuralgia is a unilateral or bilateral radiating pain with paresthesias commonly manifesting as paroxysmal episodes and involving the occipital and parietal regions. Common causes of occipital neuralgia include irritation or injury to the divisions of the occipital nerve, myofascial spasm, and focal entrapment of the occipital nerve. Treatment options include medication therapy, occipital nerve blocks, and surgical techniques. BTX-A, which has shown promise in relief of other headache types, may prove a viable therapeutic option for occipital neuralgia pain. Botulinum toxin type-A (reconstituted in 3 cc of saline) was injected into regions traversed by the greater and lesser occipital nerve in 6 subjects diagnosed with occipital neuralgia. Subjects were instructed to report their daily pain level (on a visual analog pain scale), their ability to perform daily activities (on several quality of life instruments) and their daily pain medication usage (based on a self-reported log), 2 weeks prior to the injection therapy and 12 weeks following injection therapy. Data were analyzed for significant variation from baseline values. The dull/aching and pin/needles types of pain reported by the subjects did not show a statistically significant improvement during the trial period. The sharp/shooting type of pain, however, showed improvement during most of the trial period except weeks 3-4 and 5-6. The quality of life measures exhibited some improvement. The headache-specific quality of life measure showed significant improvement by 6 weeks which continued through week 12. The general health- and depression-related measures showed no statistical improvement. No significant reduction in pain medication usage was demonstrated. Our results indicate that BTX-A improved the sharp/shooting type of pain most commonly known to be associated with occipital neuralgia. Additionally, the quality of life measures assessing burden and long-term impact of the headaches, further corroborated improvement seen in daily head pain.

Effects of external applications of No. 2 fuel oil on common eider eggs

USGS Publications Warehouse

Szaro, Robert C.; Albers, P.H.; Wolfe, Douglas A.

1977-01-01

Because eggs of marine birds may be exposed to oil adhering to the feathers of adult birds, a study was undertaken to determine the effects of oil contamination. Two hundred common eider eggs were divided into four experimental sets of 50 each. Two sets were treated with No. 2 fuel oil in amounts of 5 microliters to 20 microliters; a third with 20 microliters of propylene glycol, a neutral blocking agent. The fourth set served as a control. Hatching success was 96 percent for the eggs treated with 20 microliters propylene glycol, 96 percent for the controls and 92 percent for the eggs treated with 5 microliters oil hatched. Only 69 percent of the eggs treated with 20 microliters of oil survived - a significant reduction in hatchability (P 0.05). Mean Hatching weights for all sets were statistically equal. Thus, oil pollution may significantly increase embryonic mortality in marine birds.

Mycorrhizal diversity in the rhizosphere of sugarcane and grass on different soil types

NASA Astrophysics Data System (ADS)

Ratri Cahyani, Vita; Rastikawati, Dewi; Yuniardi, Nestri; Syamsiyah, Jauhari; Suntoro

2017-11-01

Mycorrhiza has been known well as beneficial microbiota for supporting plant growth and production. Understanding of the variability and the consistency of the mycorrhizal diversity on various habitats is important for developing mycorrhizal utilization. Mycorrhizal diversity in the rhizosphere of sugarcane from 4 (four) soil types and the rhizosphere of grass from 3 (three) soil types were investigated in the present study. The results showed that Glomus indicated as a versatile genus because it was found as a common and dominant genus in the sugarcane rhizosphere on all of four soil types (Alfisol, Andisol, Inceptisol, Vertisol) and in the grass rhizosphere on all of three soil types (Ultisol, Oxisol, Histosol). In addition, Acaulospora was found as a common genus in grass rhizosphere. Statistical analysis indicated that P availability in the rhizosphere of sugarcane had a significantly negative correlation with mycorrhizal spore density, in which decreasing P availability significantly related with increasing spore density.

Descriptive and inferential statistical methods used in burns research.

PubMed

Al-Benna, Sammy; Al-Ajam, Yazan; Way, Benjamin; Steinstraesser, Lars

2010-05-01

Burns research articles utilise a variety of descriptive and inferential methods to present and analyse data. The aim of this study was to determine the descriptive methods (e.g. mean, median, SD, range, etc.) and survey the use of inferential methods (statistical tests) used in articles in the journal Burns. This study defined its population as all original articles published in the journal Burns in 2007. Letters to the editor, brief reports, reviews, and case reports were excluded. Study characteristics, use of descriptive statistics and the number and types of statistical methods employed were evaluated. Of the 51 articles analysed, 11(22%) were randomised controlled trials, 18(35%) were cohort studies, 11(22%) were case control studies and 11(22%) were case series. The study design and objectives were defined in all articles. All articles made use of continuous and descriptive data. Inferential statistics were used in 49(96%) articles. Data dispersion was calculated by standard deviation in 30(59%). Standard error of the mean was quoted in 19(37%). The statistical software product was named in 33(65%). Of the 49 articles that used inferential statistics, the tests were named in 47(96%). The 6 most common tests used (Student's t-test (53%), analysis of variance/co-variance (33%), chi(2) test (27%), Wilcoxon & Mann-Whitney tests (22%), Fisher's exact test (12%)) accounted for the majority (72%) of statistical methods employed. A specified significance level was named in 43(88%) and the exact significance levels were reported in 28(57%). Descriptive analysis and basic statistical techniques account for most of the statistical tests reported. This information should prove useful in deciding which tests should be emphasised in educating burn care professionals. These results highlight the need for burn care professionals to have a sound understanding of basic statistics, which is crucial in interpreting and reporting data. Advice should be sought from professionals in the fields of biostatistics and epidemiology when using more advanced statistical techniques. Copyright 2009 Elsevier Ltd and ISBI. All rights reserved.

K-nearest neighbors based methods for identification of different gear crack levels under different motor speeds and loads: Revisited

NASA Astrophysics Data System (ADS)

Wang, Dong

2016-03-01

Gears are the most commonly used components in mechanical transmission systems. Their failures may cause transmission system breakdown and result in economic loss. Identification of different gear crack levels is important to prevent any unexpected gear failure because gear cracks lead to gear tooth breakage. Signal processing based methods mainly require expertize to explain gear fault signatures which is usually not easy to be achieved by ordinary users. In order to automatically identify different gear crack levels, intelligent gear crack identification methods should be developed. The previous case studies experimentally proved that K-nearest neighbors based methods exhibit high prediction accuracies for identification of 3 different gear crack levels under different motor speeds and loads. In this short communication, to further enhance prediction accuracies of existing K-nearest neighbors based methods and extend identification of 3 different gear crack levels to identification of 5 different gear crack levels, redundant statistical features are constructed by using Daubechies 44 (db44) binary wavelet packet transform at different wavelet decomposition levels, prior to the use of a K-nearest neighbors method. The dimensionality of redundant statistical features is 620, which provides richer gear fault signatures. Since many of these statistical features are redundant and highly correlated with each other, dimensionality reduction of redundant statistical features is conducted to obtain new significant statistical features. At last, the K-nearest neighbors method is used to identify 5 different gear crack levels under different motor speeds and loads. A case study including 3 experiments is investigated to demonstrate that the developed method provides higher prediction accuracies than the existing K-nearest neighbors based methods for recognizing different gear crack levels under different motor speeds and loads. Based on the new significant statistical features, some other popular statistical models including linear discriminant analysis, quadratic discriminant analysis, classification and regression tree and naive Bayes classifier, are compared with the developed method. The results show that the developed method has the highest prediction accuracies among these statistical models. Additionally, selection of the number of new significant features and parameter selection of K-nearest neighbors are thoroughly investigated.

Association Between Harmful Oral Habits and Sign and Symptoms of Temporomandibular Joint Disorders Among Adolescents.

PubMed

Motghare, Vaibhav; Kumar, Jayaprakash; Kamate, Shivalingesh; Kushwaha, Sumedha; Anand, Richa; Gupta, Neha; Gupta, Bhuvandeep; Singh, Ishan

2015-08-01

Temporomandibular disorder (TDM) is defined as a heterogenous group of psychophysiological disorders commonly characterised by orofacial pain, chewing dysfunction or both. Various Epidemiological studies had shown occurrence of TMD in all age groups including children. Also research had shown that non nutritional oral habits to be associated with TMD. Present study aimed to find whether harmful oral habits are associated with sign and symptoms of TMD among adolescents in Greater Noida. Schools in Gautam Buddha district and descriptive study. Cross sectional study was carried out among 240 adolescents (10 - 19 years) studying in schools of Greater Noida. Study population were selected by random sampling to whom screening questionnaires recommended by American Academy of Orofacial Pain (AAOP) were distributed. Patient history and clinical examination was used to determine harmful oral habits. Data analysis was done in SPSS version 21 and Chi-square test was applied. Sixty one participants (25.4%) displayed no sign and symptoms of TMD, 34 (14.2%) responded affirmatively to atleast one item on the questionnaire and 108(46%) gave at least three affirmative responses. Headache, Neckpain and Toothache were most frequent reported sign and symptoms of TMD (46.2%). There was statistically significant association between gender and sign and symptoms of TMD on three items of the questionnaire (p < 0.05). Nail Biting (45.8%), Biting Lips/objects (37%) were most common habits among the study group. There was statistically significant association between Nail Biting (p = 0.001), Lip Biting/ object biting (p=0.001), Grinding of teeth (p = 0.01) and sign and symptoms of TMD. A statistically significant association was found between nail biting, lip/ object biting and grinding of teeth with signs and/or symptoms of TMD. Thus there is need for preventive dental treatment and community dental education so that young adults realize importance of early diagnosis and treatment of TMJ disorders.

Short-term Outcomes After Open and Laparoscopic Colostomy Creation.

PubMed

Ivatury, Srinivas Joga; Bostock Rosenzweig, Ian C; Holubar, Stefan D

2016-06-01

Colostomy creation is a common procedure performed in colon and rectal surgery. Outcomes by technique have not been well studied. This study evaluated outcomes related to open versus laparoscopic colostomy creation. This was a retrospective review of patients undergoing colostomy creation using univariate and multivariate propensity score analyses. Hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program database were included. Data on patients were obtained from the American College of Surgeons National Surgical Quality Improvement Program 2005-2011 Participant Use Data Files. We measured 30-day mortality, 30-day complications, and predictors of 30-day mortality. A total of 2179 subjects were in the open group and 1132 in the laparoscopic group. The open group had increased age (open, 64 years vs laparoscopic, 60 years), admission from facility (17.0% vs 14.9%), and disseminated cancer (26.1% vs 21.4%). All were statistically significant. The open group had a significantly higher percentage of emergency operations (24.9% vs 7.9%). Operative time was statistically different (81 vs 86 minutes). Thirty-day mortality was significantly higher in the open group (8.7% vs 3.5%), as was any 30-day complication (25.4% vs 17.0%). Propensity-matching analysis on elective patients only revealed that postoperative length of stay and rate of any wound complication were statistically higher in the open group. Multivariate analysis for mortality was performed on the full, elective, and propensity-matched cohorts; age >65 years and dependent functional status were associated with an increased risk of mortality in all of the models. This study has the potential for selection bias and limited generalizability. Colostomy creation at American College of Surgeons National Surgical Quality Improvement Program hospitals is more commonly performed open rather than laparoscopically. Patient age >65 years and dependent functional status are associated with an increased risk of 30-day mortality.

Common variants in the TPH2 promoter confer susceptibility to paranoid schizophrenia.

PubMed

Yi, Zhenghui; Zhang, Chen; Lu, Weihong; Song, Lisheng; Liu, Dentang; Xu, Yifeng; Fang, Yiru

2012-07-01

Serotonergic system-related genes may be good candidates in investigating the genetic basis of schizophrenia. Our previous study suggested that promoter region of tryptophan hydroxylase 2 gene (TPH2) may confer the susceptibility to paranoid schizophrenia. In this study, we investigated whether common variants within TPH2 promoter may predispose to paranoid schizophrenia in Han Chinese. A total of 509 patients who met DSM-IV criteria for paranoid schizophrenia and 510 matched healthy controls were recruited for this study. Five polymorphisms within TPH2 promoter region were tested. No statistically significant differences were found in allele or genotype frequencies between schizophrenic patients and healthy controls. The frequency of the rs4448731T-rs6582071A-rs7963803A-rs4570625T-rs11178997A haplotype was significantly higher in cases compared to the controls (P = 0.003; OR = 1.49; 95% CI, 1.15-1.95). Our results suggest that the common variants within TPH2 promoter are associated with paranoid schizophrenia in Han Chinese. Further studies in larger samples are warranted to elucidate the role of TPH2 in the etiology of paranoid schizophrenia.

Did the 1997 Balanced Budget Act Reduce Use of Physical and Occupational Therapy Services?

PubMed Central

Latham, Nancy K.; Jette, Alan M.; Ngo, Long H.; Soukup, Jane; Iezzoni, Lisa I.

2012-01-01

Objective To investigate whether use of physical therapy (PT) and occupational therapy (OT) services decreased after the passage of the 1997 Balanced Budget Act (BBA). Design Data from the nationally representative Medicare Current Beneficiary Survey (MCBS) were merged with Medicare claims data. We conducted cross-sectional analyses of data from 1995 (n=7978), 1999 (n=7863), and 2001 (n=7973). All analyses used MCBS sampling weights to provide estimates that can be generalized to the Medicare population with 5 common conditions. Settings Skilled nursing facilities (SNFs), home health agencies, inpatient rehabilitation facilities (IRFs), and outpatient rehabilitation settings. Participants Medicare beneficiaries who participated in the MCBS survey in each of the study years and had 1 or more of the following conditions: acute stroke, acute myocardial infarction, chronic obstructive pulmonary disease, arthritis or degenerative joint disease, or mobility problems. Interventions Not applicable. Main Outcome Measures Percentage of persons meeting our inclusion criteria who received PT or OT in each setting, and total units of PT and OT received in each setting. Results Multivariable logistic regression revealed no statistically significantly differences in the proportion of people who met our inclusion criteria who used PT or OT from home health agencies across the 3 time points. For SNFs, an increase in the odds of receiving PT was statistically significant from 1995 to 1999 (odds ratio [OR]=1.42; 95% confidence interval [CI], 1.19–1.69) and 1995 to 2001 (OR=1.69; 95% CI, 1.39–2.05). For IRF and outpatient settings, a significant increase was observed between 1995 and 2001 (OR=1.71, OR=1.27, respectively). For OT, a statistically significant increase was observed for IRF and outpatient rehabilitation settings from 1995 to 2001. For SNF, the increase was statistically significant from 1995 to 1999 and 1995 to 2001. Mean total PT and OT units received also increased across all settings from 1995 to 2001 except for IRFs. Conclusions Despite BBA mandates restricting postacute care expenditures, this nationally representative study showed no decreases in the percentage of Medicare beneficiaries with 5 common diagnoses receiving PT and/or OT across all settings and no decreases in units of PT and/or OT services received between 1995 and 2001 except for those in IRFs. This study suggests that the delivery of PT and OT services did not decline among persons with conditions where rehabilitation services are often clinically indicated. PMID:18452725

Common pitfalls in statistical analysis: Understanding the properties of diagnostic tests - Part 1.

PubMed

Ranganathan, Priya; Aggarwal, Rakesh

2018-01-01

In this article in our series on common pitfalls in statistical analysis, we look at some of the attributes of diagnostic tests (i.e., tests which are used to determine whether an individual does or does not have disease). The next article in this series will focus on further issues related to diagnostic tests.

The Evaluation of IL6 and ESR1 Gene Polymorphisms in Primary Dysmenorrhea.

PubMed

Ozsoy, Asker Zeki; Karakus, Nevin; Yigit, Serbulent; Cakmak, Bulent; Nacar, Mehmet Can; Yılmaz Dogru, Hatice

2016-01-01

Primary dysmenorrhea is the most common gynecological complaint with painful menstrual cramps in pelvis without any pathology. It affects about half of menstruating women, and it causes significant disruption in quality of life. We investigated the association between IL6 gene promoter and ESR1 gene XbaI and PvuII polymorphisms and primary dysmenorrhea. In this case-control study, 152 unrelated young women with primary dysmenorrhea and 150 unrelated healthy age-matched controls participated. Genomic DNA was isolated and IL6 and ESR1 gene polymorphisms were genotyped using PCR-based RFLP assay. The distribution of genotype and allele frequencies of IL6 gene promoter and ESR1 gene XbaI polymorphisms were not statistically different between patients and controls (p > 0.05). However, the genotype and allele frequencies of ESR1 gene PvuII polymorphism showed statistically significant differences between primary dysmenorrhea patients and controls (p = 0.009 and p = 0.021, respectively). Statistically significant associations were also observed between age and married status of primary dysmenorrhea patients and ESR1 gene PvuII polymorphism (p = 0.044 and p = 0.023, respectively). In combined genotype analyses, AG at ESR1 XbaI and TC at ESR1 PvuII loci encoded a p-value of 0.027. Thus, individuals who are heterozygote at both loci have a lower risk of developing primary dysmenorrhea. Our study suggests no strong association between IL6 gene promoter and ESR1 gene XbaI polymorphisms and primary dysmenorrhea in Turkish women. However, ESR1 gene PvuII polymorphism showed statistically significant differences between primary dysmenorrhea patients and controls. The potential association between ESR1 gene PvuII polymorphism and age and married status of dysmenorrhea patients deserves further consideration.

Effects of Plasma Rich in Growth Factors and Platelet-Rich Fibrin on Proliferation and Viability of Human Gingival Fibroblasts

PubMed Central

Vahabi, Surena; Vaziri, Shahram; Torshabi, Maryam

2015-01-01

Objectives: Platelet preparations are commonly used to enhance bone and soft tissue regeneration. Considering the existing controversies on the efficacy of platelet products for tissue regeneration, more in vitro studies are required. The aim of the present study was to compare the in vitro effects of plasma rich in growth factors (PRGF) and platelet-rich fibrin (PRF) on proliferation and viability of human gingival fibroblasts (HGFs). Materials and Methods: Anitua’s PRGF and Choukran’s PRF were prepared according to the standard protocols. After culture periods of 24, 48 and 72 hours, proliferation of HGFs was evaluated by the methyl thiazol tetrazolium assay. Statistical analysis was performed using one-way ANOVA followed by Tukey-Kramer’s multiple comparisons and P-values<0.05 were considered statistically significant. Results: PRGF treatment induced statistically significant (P<0.001) proliferation of HGF cells compared to the negative control (100% viability) at 24, 48 and 72 hours in values of 123%±2.25%, 102%±2.8% and 101%±3.92%, respectively. The PRF membrane treatment of HGF cells had a statistically significant effect on cell proliferation (21%±1.73%, P<0.001) at 24 hours compared to the negative control. However, at 48 and 72 hours after treatment, PRF had a negative effect on HGF cell proliferation and caused 38% and 60% decrease in viability and proliferation compared to the negative control, respectively. The HGF cell proliferation was significantly higher in PRGF than in PRF group (P< 0.001). Conclusion: This study demonstrated that PRGF had a strong stimulatory effect on HGF cell viability and proliferation compared to PRF. PMID:26877740

Success rates of a skeletal anchorage system in orthodontics: A retrospective analysis.

PubMed

Lam, Raymond; Goonewardene, Mithran S; Allan, Brent P; Sugawara, Junji

2018-01-01

To evaluate the premise that skeletal anchorage with SAS miniplates are highly successful and predictable for a range of complex orthodontic movements. This retrospective cross-sectional analysis consisted of 421 bone plates placed by one clinician in 163 patients (95 female, 68 male, mean age 29.4 years ± 12.02). Simple descriptive statistics were performed for a wide range of malocclusions and desired movements to obtain success, complication, and failure rates. The success rate of skeletal anchorage system miniplates was 98.6%, where approximately 40% of cases experienced mild complications. The most common complication was soft tissue inflammation, which was amenable to focused oral hygiene and antiseptic rinses. Infection occurred in approximately 15% of patients where there was a statistically significant correlation with poor oral hygiene. The most common movements were distalization and intrusion of teeth. More than a third of the cases involved complex movements in more than one plane of space. The success rate of skeletal anchorage system miniplates is high and predictable for a wide range of complex orthodontic movements.

Coherent instability in wall-bounded turbulence

NASA Astrophysics Data System (ADS)

Hack, M. J. Philipp

2017-11-01

Hairpin vortices are commonly considered one of the major classes of coherent fluid motions in shear layers, even as their significance in the grand scheme of turbulence has remained an openly debated question. The statistical prevalence of the dynamic process that gives rise to the hairpins across different types of flows suggests an origin in a robust common mechanism triggered by conditions widespread in wall-bounded shear layers. This study seeks to shed light on the physical process which drives the generation of hairpin vortices. It is primarily facilitated through an algorithm based on concepts developed in the field of computer vision which allows the topological identification and analysis of coherent flow processes across multiple scales. Application to direct numerical simulations of boundary layers enables the time-resolved sampling and exploration of the hairpin process in natural flow. The analysis yields rich statistical results which lead to a refined characterization of the hairpin process. Linear stability theory offers further insight into the flow physics and especially into the connection between the hairpin and exponential amplification mechanisms. The results also provide a sharpened understanding of the underlying causality of events.

Gender and laterality in semicircular canal dehiscence syndrome.

PubMed

Karimnejad, K; Czerny, M S; Lookabaugh, S; Lee, D J; Mikulec, A A

2016-08-01

To determine if there is gender or laterality predilection in patients with semicircular canal dehiscence syndrome. A multi-institutional chart review was performed to identify patients diagnosed with semicircular canal dehiscence between 2000 and 2015. A systematic literature search was conducted using PubMed to further identify patients with semicircular canal dehiscence. Age, gender and laterality data were collected. Statistical analysis was performed to evaluate for gender or laterality preponderance. A total of 682 patients with semicircular canal dehiscence were identified by literature and chart review. Mean age of diagnosis was 49.75 years (standard deviation = 15.33). Semicircular canal dehiscence was associated with a statistically significant female predominance (chi-square = 7.185, p = 0.007); the female-to-male ratio was 1.2 to 1. Left-sided semicircular canal dehiscence was most common, followed by right-sided then bilateral (chi-square = 23.457, p < 0.001). Semicircular canal dehiscence syndrome is most commonly left-sided and exhibits a female predominance. This may be secondary to morphological cerebral hemisphere asymmetries in both sexes and a predilection of women to seek more medical care than men.

Statistical differences between relative quantitative molecular fingerprints from microbial communities.

PubMed

Portillo, M C; Gonzalez, J M

2008-08-01

Molecular fingerprints of microbial communities are a common method for the analysis and comparison of environmental samples. The significance of differences between microbial community fingerprints was analyzed considering the presence of different phylotypes and their relative abundance. A method is proposed by simulating coverage of the analyzed communities as a function of sampling size applying a Cramér-von Mises statistic. Comparisons were performed by a Monte Carlo testing procedure. As an example, this procedure was used to compare several sediment samples from freshwater ponds using a relative quantitative PCR-DGGE profiling technique. The method was able to discriminate among different samples based on their molecular fingerprints, and confirmed the lack of differences between aliquots from a single sample.

Towards Principled Experimental Study of Autonomous Mobile Robots

NASA Technical Reports Server (NTRS)

Gat, Erann

1995-01-01

We review the current state of research in autonomous mobile robots and conclude that there is an inadequate basis for predicting the reliability and behavior of robots operating in unengineered environments. We present a new approach to the study of autonomous mobile robot performance based on formal statistical analysis of independently reproducible experiments conducted on real robots. Simulators serve as models rather than experimental surrogates. We demonstrate three new results: 1) Two commonly used performance metrics (time and distance) are not as well correlated as is often tacitly assumed. 2) The probability distributions of these performance metrics are exponential rather than normal, and 3) a modular, object-oriented simulation accurately predicts the behavior of the real robot in a statistically significant manner.

Differences in Bacterial Colonization and Biofilm Formation Property of Uropathogens between the Two most Commonly used Indwelling Urinary Catheters.

PubMed

Verma, Amit; Bhani, Deepa; Tomar, Vinay; Bachhiwal, Rekha; Yadav, Shersingh

2016-06-01

Catheter Associated Urinary Tract Infections (CAUTI) are one of the most common cause of nosocomial infections. Many bacterial species show biofilm production, which provides survival benefit to them by providing protection from environmental stresses and causing decreased susceptibility to antimicrobial agents. Two most common types of catheters used in our setup are pure silicone catheter and silicone coated latex catheter. The advantage of pure silicone catheter for long term catheterization is well established. But there is still a controversy about any advantage of the silicone catheter regarding bacterial colonization rates and their biofilm production property. The aim of our study was to compare the bacterial colonization and the biofilm formation property of the colonizing bacteria in patients with indwelling pure silicone and silicone coated latex catheters. This prospective observational study was conducted in the Urology Department of our institute. Patients who needed catheterization for more than 5 days during the period July 2015 to January 2016 and had sterile precatheterisation urine were included in the study. Patients were grouped into 2 groups of 50 patients each, Group A with the pure silicone catheter and Group B with the silicone coated latex catheter. Urine culture was done on the 6(th) day of indwelling urinary catheter drainage. If growth was detected, then that bacterium was tested for biofilm production property by tissue culture plate method. Statistical analyses were performed using the Statistical Package for the Social Science Version 22 (SPSS-22). After 5 days of indwelling catheterization, the pure silicone catheter had significantly less bacterial colonization than the silicone coated latex catheter (p-value=0.03) and the biofilm forming property of colonizing bacteria was also significantly less in the pure silicone catheter as compared to the silicone coated latex catheter (p-value=0.02). There were no significant differences in the colonizing bacteria in the 2 groups. In both the groups the most common bacteria were Escherichia coli. The pure silicone catheter is advantageous over the silicone coated latex catheter in terms of incidence of bacterial colonization as well as the biofilm formation and hence in the management of CAUTI.

Increasing URM Undergraduate Student Success through Assessment-Driven Interventions: A Multiyear Study Using Freshman-Level General Biology as a Model System.

PubMed

Carmichael, Mary C; St Clair, Candace; Edwards, Andrea M; Barrett, Peter; McFerrin, Harris; Davenport, Ian; Awad, Mohamed; Kundu, Anup; Ireland, Shubha Kale

2016-01-01

Xavier University of Louisiana leads the nation in awarding BS degrees in the biological sciences to African-American students. In this multiyear study with ∼5500 participants, data-driven interventions were adopted to improve student academic performance in a freshman-level general biology course. The three hour-long exams were common and administered concurrently to all students. New exam questions were developed using Bloom's taxonomy, and exam results were analyzed statistically with validated assessment tools. All but the comprehensive final exam were returned to students for self-evaluation and remediation. Among other approaches, course rigor was monitored by using an identical set of 60 questions on the final exam across 10 semesters. Analysis of the identical sets of 60 final exam questions revealed that overall averages increased from 72.9% (2010) to 83.5% (2015). Regression analysis demonstrated a statistically significant correlation between high-risk students and their averages on the 60 questions. Additional analysis demonstrated statistically significant improvements for at least one letter grade from midterm to final and a 20% increase in the course pass rates over time, also for the high-risk population. These results support the hypothesis that our data-driven interventions and assessment techniques are successful in improving student retention, particularly for our academically at-risk students. © 2016 M. C. Carmichael et al. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

The Heuristic Value of p in Inductive Statistical Inference

PubMed Central

Krueger, Joachim I.; Heck, Patrick R.

2017-01-01

Many statistical methods yield the probability of the observed data – or data more extreme – under the assumption that a particular hypothesis is true. This probability is commonly known as ‘the’ p-value. (Null Hypothesis) Significance Testing ([NH]ST) is the most prominent of these methods. The p-value has been subjected to much speculation, analysis, and criticism. We explore how well the p-value predicts what researchers presumably seek: the probability of the hypothesis being true given the evidence, and the probability of reproducing significant results. We also explore the effect of sample size on inferential accuracy, bias, and error. In a series of simulation experiments, we find that the p-value performs quite well as a heuristic cue in inductive inference, although there are identifiable limits to its usefulness. We conclude that despite its general usefulness, the p-value cannot bear the full burden of inductive inference; it is but one of several heuristic cues available to the data analyst. Depending on the inferential challenge at hand, investigators may supplement their reports with effect size estimates, Bayes factors, or other suitable statistics, to communicate what they think the data say. PMID:28649206

The Heuristic Value of p in Inductive Statistical Inference.

PubMed

Krueger, Joachim I; Heck, Patrick R

2017-01-01

Many statistical methods yield the probability of the observed data - or data more extreme - under the assumption that a particular hypothesis is true. This probability is commonly known as 'the' p -value. (Null Hypothesis) Significance Testing ([NH]ST) is the most prominent of these methods. The p -value has been subjected to much speculation, analysis, and criticism. We explore how well the p -value predicts what researchers presumably seek: the probability of the hypothesis being true given the evidence, and the probability of reproducing significant results. We also explore the effect of sample size on inferential accuracy, bias, and error. In a series of simulation experiments, we find that the p -value performs quite well as a heuristic cue in inductive inference, although there are identifiable limits to its usefulness. We conclude that despite its general usefulness, the p -value cannot bear the full burden of inductive inference; it is but one of several heuristic cues available to the data analyst. Depending on the inferential challenge at hand, investigators may supplement their reports with effect size estimates, Bayes factors, or other suitable statistics, to communicate what they think the data say.

Evaluating statistical and clinical significance of intervention effects in single-case experimental designs: an SPSS method to analyze univariate data.

PubMed

Maric, Marija; de Haan, Else; Hogendoorn, Sanne M; Wolters, Lidewij H; Huizenga, Hilde M

2015-03-01

Single-case experimental designs are useful methods in clinical research practice to investigate individual client progress. Their proliferation might have been hampered by methodological challenges such as the difficulty applying existing statistical procedures. In this article, we describe a data-analytic method to analyze univariate (i.e., one symptom) single-case data using the common package SPSS. This method can help the clinical researcher to investigate whether an intervention works as compared with a baseline period or another intervention type, and to determine whether symptom improvement is clinically significant. First, we describe the statistical method in a conceptual way and show how it can be implemented in SPSS. Simulation studies were performed to determine the number of observation points required per intervention phase. Second, to illustrate this method and its implications, we present a case study of an adolescent with anxiety disorders treated with cognitive-behavioral therapy techniques in an outpatient psychotherapy clinic, whose symptoms were regularly assessed before each session. We provide a description of the data analyses and results of this case study. Finally, we discuss the advantages and shortcomings of the proposed method. Copyright © 2014. Published by Elsevier Ltd.

Using Social Network Analysis to Better Understand Compulsive Exercise Behavior Among a Sample of Sorority Members.

PubMed

Patterson, Megan S; Goodson, Patricia

2017-05-01

Compulsive exercise, a form of unhealthy exercise often associated with prioritizing exercise and feeling guilty when exercise is missed, is a common precursor to and symptom of eating disorders. College-aged women are at high risk of exercising compulsively compared with other groups. Social network analysis (SNA) is a theoretical perspective and methodology allowing researchers to observe the effects of relational dynamics on the behaviors of people. SNA was used to assess the relationship between compulsive exercise and body dissatisfaction, physical activity, and network variables. Descriptive statistics were conducted using SPSS, and quadratic assignment procedure (QAP) analyses were conducted using UCINET. QAP regression analysis revealed a statistically significant model (R 2 = .375, P < .0001) predicting compulsive exercise behavior. Physical activity, body dissatisfaction, and network variables were statistically significant predictor variables in the QAP regression model. In our sample, women who are connected to "important" or "powerful" people in their network are likely to have higher compulsive exercise scores. This result provides healthcare practitioners key target points for intervention within similar groups of women. For scholars researching eating disorders and associated behaviors, this study supports looking into group dynamics and network structure in conjunction with body dissatisfaction and exercise frequency.

Sampling methods to the statistical control of the production of blood components.

PubMed

Pereira, Paulo; Seghatchian, Jerard; Caldeira, Beatriz; Santos, Paula; Castro, Rosa; Fernandes, Teresa; Xavier, Sandra; de Sousa, Gracinda; de Almeida E Sousa, João Paulo

2017-12-01

The control of blood components specifications is a requirement generalized in Europe by the European Commission Directives and in the US by the AABB standards. The use of a statistical process control methodology is recommended in the related literature, including the EDQM guideline. The control reliability is dependent of the sampling. However, a correct sampling methodology seems not to be systematically applied. Commonly, the sampling is intended to comply uniquely with the 1% specification to the produced blood components. Nevertheless, on a purely statistical viewpoint, this model could be argued not to be related to a consistent sampling technique. This could be a severe limitation to detect abnormal patterns and to assure that the production has a non-significant probability of producing nonconforming components. This article discusses what is happening in blood establishments. Three statistical methodologies are proposed: simple random sampling, sampling based on the proportion of a finite population, and sampling based on the inspection level. The empirical results demonstrate that these models are practicable in blood establishments contributing to the robustness of sampling and related statistical process control decisions for the purpose they are suggested for. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preservice Secondary Mathematics Teachers' Statistical Knowledge: A Snapshot of Strengths and Weaknesses

ERIC Educational Resources Information Center

Lovett, Jennifer N.; Lee, Hollylynne S.

2017-01-01

Amid the implementation of new curriculum standard regarding statistics and new recommendations for preservice secondary mathematics teachers [PSMTs] to teach statistics, there is a need to examine the current state of PSMTs' common statistical knowledge. This study reports on the statistical knowledge 217 PSMTs from a purposeful sample of 18…

Longitudinal Examination of Links Between Risk Factors for the Metabolic Syndrome and Both Age and Fasting Glucose Levels in Nondiabetic Subjects.

PubMed

Preuss, Harry G; Kaats, Gilbert R; Mrvichin, Nate; Bagchi, Debasis; Swaroop, Anand

2018-01-01

Previous evaluations in nondiabetic subjects revealed statistically significant correlations between fasting blood glucose (FBG) levels used as an estimate of insulin resistance and many components constituting the metabolic syndrome. Similar significant correlations were not found employing chronological age as the independent variable in the same nondiabetic individuals. The major purpose here was to replicate as well as corroborate the previous cross-sectional observations, emphasizing results obtained from data collected longitudinally. Material was assessed from 99 nondiabetic volunteers who had undergone 2 separate baseline measurements carried out over a minimum of 5 and up to a maximum of 20 years. Findings from the starting baseline measurements mimicked many observations perceived in the earlier published cross-sectional material. The following correlations with elements constituting the metabolic syndrome using FBG as an independent variable were once more statistically significantly positive: scale weight, fat mass, circulating levels of triglycerides and high-sensitivity C-reactive protein (hsCRP). High-density lipoprotein (HDL) cholesterol was once again appropriately significant in a negative direction. In contrast, the same correlations were generally nonsignificant when age replaced FBG as the independent variable. Examining the 2 data sets over the 5-20-year intervals, FBG increased statistically significantly over time. However, the average increase clinically was relatively minor: -92.1 mg/dL ± 1.1 (SEM) vs 95.1 mg/dL ± 1.1 (SEM), p < 0.007. When the actual changes (delta) in the dependent parameters were correlated with the individual passages of time (intervals in years), only downward changes in aspartate aminotransferase (AST) levels were statistically significant. Fat-free mass showed a trend downward, whereas fat mass, trunk fat, and triglycerides merely demonstrated trends upward. Current findings gathered over years are consistent with the original hypothesis that maintaining relatively low, stable circulating glucose levels during aging retards the development and intensity of many common manifestations of the metabolic syndrome.

Study/experimental/research design: much more than statistics.

PubMed

Knight, Kenneth L

2010-01-01

The purpose of study, experimental, or research design in scientific manuscripts has changed significantly over the years. It has evolved from an explanation of the design of the experiment (ie, data gathering or acquisition) to an explanation of the statistical analysis. This practice makes "Methods" sections hard to read and understand. To clarify the difference between study design and statistical analysis, to show the advantages of a properly written study design on article comprehension, and to encourage authors to correctly describe study designs. The role of study design is explored from the introduction of the concept by Fisher through modern-day scientists and the AMA Manual of Style. At one time, when experiments were simpler, the study design and statistical design were identical or very similar. With the complex research that is common today, which often includes manipulating variables to create new variables and the multiple (and different) analyses of a single data set, data collection is very different than statistical design. Thus, both a study design and a statistical design are necessary. Scientific manuscripts will be much easier to read and comprehend. A proper experimental design serves as a road map to the study methods, helping readers to understand more clearly how the data were obtained and, therefore, assisting them in properly analyzing the results.

Prevalence and distribution of selected developmental dental anomalies in an Indian population.

PubMed

Gupta, Saurabh K; Saxena, Payal; Jain, Sandhya; Jain, Deshraj

2011-06-01

The purpose of this study was to determine the prevalence of developmental dental anomalies in an Indian population and to statistically analyze the distribution of these anomalies. The study was based on clinical examination, evaluation of dental casts, and panoramic radiographs of 1123 Indian subjects (572 males, 551 females), who visited the outpatient clinic at Government Dental College, Indore between November 2009 and September 2010, after obtaining their informed consent. These patients were examined for the following developmental dental anomalies: shape anomalies (microdontia, talon cusp, dens evaginatus, fusion, taurodontism), number anomalies (hypodontia, oligodontia, anodontia), structural anomalies (amelogenesis imperfecta, dentinogenesis imperfecta) and positional anomalies (ectopic eruption, rotation, impaction). The percentages of these anomalies were assessed for the whole group and compared using statistical analysis. Among the 1123 subjects, a total of 385 individuals (34.28%) presented with the selected developmental dental anomalies. The distribution by sex was 197 males (34.44%), and 188 females (34.06%). Out of the total 1123 individuals, 351 (31.26%) exhibited at least one anomaly, 28 (2.49 %) showed two anomalies and 6 (0.53%) displayed more than two anomalies. P values indicated that the dental anomalies were statistically independent of sex. On intergroup comparison, positional anomalies were significantly most prevalent (P < 0.05) in the Indian population. The most common developmental dental anomaly was rotation (10.24%), followed by ectopic eruption (7.93%). The next common group was number anomalies. The most common number anomaly was hypodontia (4.19%), which had a higher frequency than hyperdontia (2.40%). Analyzing the next prevalent group of shape anomalies, microdontia (2.58%) was found to be the most common, followed by taurodontism (2.49%), dens evaginatus (2.40%) and talon cusp (0.97%). Dentinogenesis imperfecta (0.09%) was the rarest, followed by amelogenesis imperfecta (0.27%) and fusion (0.27%).

Using Technology to Prompt Good Questions about Distributions in Statistics

ERIC Educational Resources Information Center

Nabbout-Cheiban, Marie; Fisher, Forest; Edwards, Michael Todd

2017-01-01

The Common Core State Standards for Mathematics envisions data analysis as a key component of K-grade 12 mathematics instruction with statistics introduced in the early grades. Nonetheless, deficiencies in statistical learning persist throughout elementary school and beyond. Too often, mathematics teachers lack the statistical knowledge for…

Research Education in Undergraduate Occupational Therapy Programs.

ERIC Educational Resources Information Center

Petersen, Paul; And Others

1992-01-01

Of 63 undergraduate occupational therapy programs surveyed, the 38 responses revealed some common areas covered: elementary descriptive statistics, validity, reliability, and measurement. Areas underrepresented include statistical analysis with or without computers, research design, and advanced statistics. (SK)

From fields to objects: A review of geographic boundary analysis

NASA Astrophysics Data System (ADS)

Jacquez, G. M.; Maruca, S.; Fortin, M.-J.

Geographic boundary analysis is a relatively new approach unfamiliar to many spatial analysts. It is best viewed as a technique for defining objects - geographic boundaries - on spatial fields, and for evaluating the statistical significance of characteristics of those boundary objects. This is accomplished using null spatial models representative of the spatial processes expected in the absence of boundary-generating phenomena. Close ties to the object-field dialectic eminently suit boundary analysis to GIS data. The majority of existing spatial methods are field-based in that they describe, estimate, or predict how attributes (variables defining the field) vary through geographic space. Such methods are appropriate for field representations but not object representations. As the object-field paradigm gains currency in geographic information science, appropriate techniques for the statistical analysis of objects are required. The methods reviewed in this paper are a promising foundation. Geographic boundary analysis is clearly a valuable addition to the spatial statistical toolbox. This paper presents the philosophy of, and motivations for geographic boundary analysis. It defines commonly used statistics for quantifying boundaries and their characteristics, as well as simulation procedures for evaluating their significance. We review applications of these techniques, with the objective of making this promising approach accessible to the GIS-spatial analysis community. We also describe the implementation of these methods within geographic boundary analysis software: GEM.

Are conventional statistical techniques exhaustive for defining metal background concentrations in harbour sediments? A case study: The Coastal Area of Bari (Southeast Italy).

PubMed

Mali, Matilda; Dell'Anna, Maria Michela; Mastrorilli, Piero; Damiani, Leonardo; Ungaro, Nicola; Belviso, Claudia; Fiore, Saverio

2015-11-01

Sediment contamination by metals poses significant risks to coastal ecosystems and is considered to be problematic for dredging operations. The determination of the background values of metal and metalloid distribution based on site-specific variability is fundamental in assessing pollution levels in harbour sediments. The novelty of the present work consists of addressing the scope and limitation of analysing port sediments through the use of conventional statistical techniques (such as: linear regression analysis, construction of cumulative frequency curves and the iterative 2σ technique), that are commonly employed for assessing Regional Geochemical Background (RGB) values in coastal sediments. This study ascertained that although the tout court use of such techniques in determining the RGB values in harbour sediments seems appropriate (the chemical-physical parameters of port sediments fit well with statistical equations), it should nevertheless be avoided because it may be misleading and can mask key aspects of the study area that can only be revealed by further investigations, such as mineralogical and multivariate statistical analyses. Copyright © 2015 Elsevier Ltd. All rights reserved.

Statistical atlas based extrapolation of CT data

NASA Astrophysics Data System (ADS)

Chintalapani, Gouthami; Murphy, Ryan; Armiger, Robert S.; Lepisto, Jyri; Otake, Yoshito; Sugano, Nobuhiko; Taylor, Russell H.; Armand, Mehran

2010-02-01

We present a framework to estimate the missing anatomical details from a partial CT scan with the help of statistical shape models. The motivating application is periacetabular osteotomy (PAO), a technique for treating developmental hip dysplasia, an abnormal condition of the hip socket that, if untreated, may lead to osteoarthritis. The common goals of PAO are to reduce pain, joint subluxation and improve contact pressure distribution by increasing the coverage of the femoral head by the hip socket. While current diagnosis and planning is based on radiological measurements, because of significant structural variations in dysplastic hips, a computer-assisted geometrical and biomechanical planning based on CT data is desirable to help the surgeon achieve optimal joint realignments. Most of the patients undergoing PAO are young females, hence it is usually desirable to minimize the radiation dose by scanning only the joint portion of the hip anatomy. These partial scans, however, do not provide enough information for biomechanical analysis due to missing iliac region. A statistical shape model of full pelvis anatomy is constructed from a database of CT scans. The partial volume is first aligned with the statistical atlas using an iterative affine registration, followed by a deformable registration step and the missing information is inferred from the atlas. The atlas inferences are further enhanced by the use of X-ray images of the patient, which are very common in an osteotomy procedure. The proposed method is validated with a leave-one-out analysis method. Osteotomy cuts are simulated and the effect of atlas predicted models on the actual procedure is evaluated.

Drought Management, Service Interruption, and Water Pricing: Evidence From Hong Kong

NASA Astrophysics Data System (ADS)

Woo, Chi-Keung

1992-10-01

Supply shortage is a common problem faced by an urban water supply system. Nonmarket programs are often used to reduce consumption. Using monthly water consumption data collected for Hong Kong for the period 1973-1984, we estimate the effect of service interruption on per capita consumption. The findings show that this effect is statistically significant but relatively small in size. A price increase of 16-35% could have produced the same amount of consumption reduction.

Metabolic profiling of human lung cancer blood plasma using 1H NMR spectroscopy

NASA Astrophysics Data System (ADS)

Kokova, Daria; Dementeva, Natalia; Kotelnikov, Oleg; Ponomaryova, Anastasia; Cherdyntseva, Nadezhda; Kzhyshkowska, Juliya

2017-11-01

Lung cancer (both small cell and non-small cell) is the second most common cancer in both men and women. The article represents results of evaluating of the plasma metabolic profiles of 100 lung cancer patients and 100 controls to investigate significant metabolites using 400 MHz 1H NMR spectrometer. The results of multivariate statistical analysis show that a medium-field NMR spectrometer can obtain the data which are already sufficient for clinical metabolomics.

Modelling gene expression profiles related to prostate tumor progression using binary states

PubMed Central

2013-01-01

Background Cancer is a complex disease commonly characterized by the disrupted activity of several cancer-related genes such as oncogenes and tumor-suppressor genes. Previous studies suggest that the process of tumor progression to malignancy is dynamic and can be traced by changes in gene expression. Despite the enormous efforts made for differential expression detection and biomarker discovery, few methods have been designed to model the gene expression level to tumor stage during malignancy progression. Such models could help us understand the dynamics and simplify or reveal the complexity of tumor progression. Methods We have modeled an on-off state of gene activation per sample then per stage to select gene expression profiles associated to tumor progression. The selection is guided by statistical significance of profiles based on random permutated datasets. Results We show that our method identifies expected profiles corresponding to oncogenes and tumor suppressor genes in a prostate tumor progression dataset. Comparisons with other methods support our findings and indicate that a considerable proportion of significant profiles is not found by other statistical tests commonly used to detect differential expression between tumor stages nor found by other tailored methods. Ontology and pathway analysis concurred with these findings. Conclusions Results suggest that our methodology may be a valuable tool to study tumor malignancy progression, which might reveal novel cancer therapies. PMID:23721350

Identification of altered pathways in breast cancer based on individualized pathway aberrance score.

PubMed

Shi, Sheng-Hong; Zhang, Wei; Jiang, Jing; Sun, Long

2017-08-01

The objective of the present study was to identify altered pathways in breast cancer based on the individualized pathway aberrance score (iPAS) method combined with the normal reference (nRef). There were 4 steps to identify altered pathways using the iPAS method: Data preprocessing conducted by the robust multi-array average (RMA) algorithm; gene-level statistics based on average Z ; pathway-level statistics according to iPAS; and a significance test dependent on 1 sample Wilcoxon test. The altered pathways were validated by calculating the changed percentage of each pathway in tumor samples and comparing them with pathways from differentially expressed genes (DEGs). A total of 688 altered pathways with P<0.01 were identified, including kinesin (KIF)- and polo-like kinase (PLK)-mediated events. When the percentage of change reached 50%, 310 pathways were involved in the total 688 altered pathways, which may validate the present results. In addition, there were 324 DEGs and 155 common genes between DEGs and pathway genes. DEGs and common genes were enriched in the same 9 significant terms, which also were members of altered pathways. The iPAS method was suitable for identifying altered pathways in breast cancer. Altered pathways (such as KIF and PLK mediated events) were important for understanding breast cancer mechanisms and for the future application of customized therapeutic decisions.

Eight year review of hemodialysis: treated patients in a tertiary center in Southern Nigeria.

PubMed

Okaka, Enajite I; Unuigbe, Evelyn I

2014-01-01

Hemodialysis (HD) is the readily available modality of renal replacement therapy in Nigeria today. The number of centers for HD continues to increase, but the majority is still located in the big cities and towns. A retrospective descriptive study in which records of patients on HD from 2004 to 2011 were reviewed. Data in respect of patients' sex, age, occupation and etiology of kidney disease were collected. Data were analyzed using Statistical Package for the Social Sciences statistical software version 16 (SPSS Inc, Chicago IL). A total of 1278 new patients were admitted for HD over the period of review; 60.9% (778) were males and 39.1% (500) females. Mean age of male patients was significantly higher than that of the females (P < 0.01). Those under the age of 40 years constituted 45.4% (580) of the study population, whereas 43.8% (560) were unskilled workers. Nearly 81.1% had CKD while 18.9% (241) had acute kidney injury (AKI). The most common cause of CKD and AKI were chronic glomerulonephritis (CGN) and sepsis respectively. This review showed a preponderance of males in the dialyzed population with males significantly older than the female patients. Patients aged ≤ 40 years and unskilled workers formed a large proportion of the population of HD treated patients. CGN and sepsis were the most common causes of CKD and AKI respectively.

EPEPT: A web service for enhanced P-value estimation in permutation tests

PubMed Central

2011-01-01

Background In computational biology, permutation tests have become a widely used tool to assess the statistical significance of an event under investigation. However, the common way of computing the P-value, which expresses the statistical significance, requires a very large number of permutations when small (and thus interesting) P-values are to be accurately estimated. This is computationally expensive and often infeasible. Recently, we proposed an alternative estimator, which requires far fewer permutations compared to the standard empirical approach while still reliably estimating small P-values [1]. Results The proposed P-value estimator has been enriched with additional functionalities and is made available to the general community through a public website and web service, called EPEPT. This means that the EPEPT routines can be accessed not only via a website, but also programmatically using any programming language that can interact with the web. Examples of web service clients in multiple programming languages can be downloaded. Additionally, EPEPT accepts data of various common experiment types used in computational biology. For these experiment types EPEPT first computes the permutation values and then performs the P-value estimation. Finally, the source code of EPEPT can be downloaded. Conclusions Different types of users, such as biologists, bioinformaticians and software engineers, can use the method in an appropriate and simple way. Availability http://informatics.systemsbiology.net/EPEPT/ PMID:22024252

A Screening Study on Dermatoses in Pregnancy

PubMed Central

Tharini, GK

2017-01-01

Introduction Pregnancy produces many cutaneous changes, some of which are specifically related to pregnancy (dermatoses of pregnancy), some are modifiable by pregnancy and others that are common are named physiologic. These physiologic skin changes, usually do not impair the health of the mother or the fetus but some of them can be cosmetically significant and of importance to the dermatologist. Aim The present study was undertaken to find out the prevalence of the physiological and pathological skin changes in pregnancy, and to correlate the prevalence of the major cutaneous changes and diseases in relation to different trimesters of pregnancy and with gravidity. Materials and Methods A cross-sectional study was conducted during the period of August 2008 to August 2010. Ethical clearance was sought from Institutional Ethical Committee. Five hundred pregnant women were randomly selected, irrespective of the duration of pregnancy and gravidity. Detailed history and complete dermatological examination was done. Results were tabulated and analysed. Statistical analysis was done by Fisher’s exact test and Chi square test. Results Physiological skin changes were seen in 94.8% of cases, with pigmentary changes being more common (90.8%). Specific dermatoses of pregnancy were observed in 14% of cases with pruritus gravidarum being the most common (10.4%). Prevalence of infection was found to 30.8% with fungal infection being the most common (23.8%). Exacerbations of systemic lupus erythematosus and neurofibromatosis was observed. Pigmentary changes, striae gravidarum and specific dermatoses of pregnancy were observed in statistically significant proportion in primigravidas and during third trimester. Conclusion This study emphasizes that the prevalence of physiological skin changes (94.8%) was much higher than specific dermatoses (14%), stressing the fact that in most instances, the skin problems during pregnancy needs only reassurance. But meticulous observation and examination should be done, as pregnancy can influence many dermatological diseases and infections. PMID:28658887

Pulmonary involvement in rheumatoid arthritis: multidetector computed tomography findings.

PubMed

Yuksekkaya, Ruken; Celikyay, Fatih; Yilmaz, Ayse; Arslan, Sule; Inanir, Ahmet; Inonu, Handan; Deniz, Caglar

2013-12-01

Pulmonary involvement in rheumatoid arthritis (RA) is common and encompasses a large spectrum of disease with different treatment options and prognoses. Therefore, assessment of these patients with multidetector computed tomography (MDCT) is vital. To evaluate the MDCT pulmonary findings of patients with RA and to compare these findings with the clinical status. Chest MDCT scans of 85 patients with RA between 2006-2012 were assessed. One patient with a pulmonary infection was excluded from the study. MDCT findings and distribution of the CT findings were examined, and patients were classified according to the predominant CT pattern. The pulmonary function test (PFT) results and categories, demographic characteristics, and clinical status of some of the patients for whom the results were obtained were evaluated, and the CT findings, PFT results, demographic characteristics, and clinical status were compared. The study group consisted of 20 men (mean age, 58.1 years ± 13.1; range, 15-77 years) and 64 women (mean age, 55.3 years ± 11.5; range, 30-84 years). The most frequent findings were nodules (78.6%) and pleural thickening (48.8%). The most common CT patterns were follicular bronchiolitis (FB) in 28 (33.3%) patients and nodular disease (ND) in 12 (14.3%) others. There was no statistically significant difference between the CT findings and PFT results, and no statistically significant difference was noted in the CT findings between symptomatic and asymptomatic patients. In addition, there were some patients who exhibited no symptoms and/or had abnormal PFT results but had abnormal CT findings. Rheumatoid arthritis is associated with a high frequency of CT findings and CT patterns, with nodules and pleural thickening being the most common CT findings and FB and ND being the most common CT patterns. MDCT identification of patients with RA may be helpful in the evaluation of pulmonary disease, even in patients without symptoms and PFT abnormalities.

Low socioeconomic status is associated with worse survival in children with cancer: a systematic review.

PubMed

Gupta, Sumit; Wilejto, Marta; Pole, Jason D; Guttmann, Astrid; Sung, Lillian

2014-01-01

While low socioeconomic status (SES) has been associated with inferior cancer outcome among adults, its impact in pediatric oncology is unclear. Our objective was therefore to conduct a systematic review to determine the impact of SES upon outcome in children with cancer. We searched Ovid Medline, EMBASE and CINAHL from inception to December 2012. Studies for which survival-related outcomes were reported by socioeconomic subgroups were eligible for inclusion. Two reviewers independently assessed articles and extracted data. Given anticipated heterogeneity, no quantitative meta-analyses were planned a priori. Of 7,737 publications, 527 in ten languages met criteria for full review; 36 studies met final inclusion criteria. In low- and middle-income countries (LMIC), lower SES was uniformly associated with inferior survival, regardless of the measure chosen. The majority of associations were statistically significant. Of 52 associations between socioeconomic variables and outcome among high-income country (HIC) children, 38 (73.1%) found low SES to be associated with worse survival, 15 of which were statistically significant. Of the remaining 14 (no association or high SES associated with worse survival), only one was statistically significant. Both HIC studies examining the effect of insurance found uninsured status to be statistically associated with inferior survival. Socioeconomic gradients in which low SES is associated with inferior childhood cancer survival are ubiquitous in LMIC and common in HIC. Future studies should elucidate mechanisms underlying these gradients, allowing the design of interventions mediating socioeconomic effects. Targeting the effect of low SES will allow for further improvements in childhood cancer survival.

Apolipoprotein E gene polymorphism and Alzheimer's disease in Chinese population: a meta-analysis

NASA Astrophysics Data System (ADS)

Liu, Mengying; Bian, Chen; Zhang, Jiqiang; Wen, Feng

2014-03-01

The relationship between Apolipoprotein E (ApoE) genotype and the risk of Alzheimer's disease (AD) is relatively well established in Caucasians, but less established in other ethnicities. To examine the association between ApoE polymorphism and the onset of AD in Chinese population, we searched the commonly used electronic databases between January 2000 and November 2013 for relevant studies. Total 20 studies, including 1576 cases and 1741 controls, were retrieved. The results showed statistically significant positive association between risk factor ɛ4 allele carriers and AD in Chinese population (OR = 3.93, 95% CI = 3.37-4.58, P < 0.00001). Genotype ApoE ɛ4/ɛ4 and ɛ4/ɛ3 have statistically significant association with AD as well (ɛ4/ɛ4: OR = 11.76, 95% CI = 6.38-21.47, P < 0.00001; ɛ4/ɛ3: OR = 3.08, 95% CI = 2.57-3.69, P < 0.00001). Furthermore, the frequency of the ApoE ɛ3 is lower in AD than that in the health controls, and the difference of ɛ3 allele is also statistically significant (OR = 0.42, 95% CI = 0.37-0.47, P < 0.00001). No significant heterogeneity was observed among all studies. This meta-analysis suggests that the subject with at least one ApoE ɛ4 allele has higher risk suffering from AD than controls in Chinese population. The results also provide a support for the protection effect of ApoE ɛ3 allele in developing AD.

In Vitro Wear Resistance of Nano-Hybrid Composite Denture Teeth.

PubMed

Munshi, Nabeel; Rosenblum, Marc; Jiang, Shuying; Flinton, Robert

2017-04-01

To evaluate the wear resistance of nano-hybrid composite denture teeth as compared to two commonly used denture teeth: interpenetrating polymer network (IPN) and double crosslinking polymethylmethacrylate (PMMA) denture teeth. 18 styli and 18 disk specimens were prepared from the three denture tooth materials: nano-hybrid composite, IPN, and double crosslinking PMMA. The specimens were mounted in a two-body wear testing machine to simulate chewing in the complete denture. The amount of wear from the styli specimens were measured before and after using a digital micrometer, and the depth of the wear track from the disk specimens was measured using a noncontact 3D optical profilometer. The total wear from each denture tooth group was compared using one-way ANOVA with a 0.05 significance level. A Tukey post hoc test was used to determine differences between the three groups. The mean total wear in the nano-hybrid composite teeth group was 1.16 mm, SD = 0.5 mm, statistically significantly higher (p ≤ 0.0001) than the IPN (mean = 0.13 mm, SD = 0.05) and double crosslinking PMMA tooth groups (mean = 0.31 mm, SD = 0.19). There was no statistically significant difference between IPN denture teeth and double crosslinking PMMA denture teeth in the amount of wear. Nano-hybrid composite denture teeth exhibited statistically significantly more wear than the IPN and double crosslinking PMMA denture teeth. © 2015 by the American College of Prosthodontists.

Nutritional status of pediatric patients with congenital heart disease: pre- and post cardiac surgery.

PubMed

Ratanachu-Ek, Suntaree; Pongdara, Aujjimavadee

2011-08-01

Malnutrition is common in infants and children with congenital heart disease (CHD). Cardiac surgery has improved patient survival and nutritional status. To evaluate the impact of cardiac surgery on nutritional status of pediatric patients with CHD. A prospective cohort study was conducted in pediatric patients with CHD, admitted for cardiac surgery at Queen Sirikit National Institute of Child Health (QSNICH), Bangkok, from August 1st, 2002 to 2003. Demographic data, cardiac and related problems were obtained before operation. Anthropometry was performed at the presentation and post cardiac surgery. Nutritional status was assessed by Z-score of weight for age (ZWA), weight for height (ZWH) and height for age (ZHA). Malnutrition was defined as Z-score <- 2 and compared pre- and post-operation using Chi-square. Paired t-test was used to compare mean Z-score and p-value < 0.05 was statistically significant. All of 161 pediatric patients with CHD undergoing cardiac surgery were 41% males and 59% females. Patients' age ranged from 1 month to 15 years. The related problems included low birth weight (28%) and feeding problem (58%). The most common CHD was ventricular septal defect (29%). The nutritional status of the patients before surgery was defined as normal 57%, malnutrition 40% and over-nutrition 3%. Malnutrition included underweight 28%, wasting 22% and stunting 16%. Post cardiac surgery, the means of ZWA, ZWH and ZHA were significantly increased and the prevalence of underweight and wasting were decreased to 17% and 6% respectively, with statistically significant from the baseline (p < 0.05). Malnutrition was found in 40% of pediatric patients with CHD and cardiac surgery has a significant positive effect on weight gain and nutritional status.

Complication Rates of Ostomy Surgery Are High and Vary Significantly Between Hospitals

PubMed Central

Sheetz, Kyle H.; Waits, Seth A.; Krell, Robert W.; Morris, Arden M.; Englesbe, Michael J.; Mullard, Andrew; Campbell, Darrell A.; Hendren, Samantha

2014-01-01

Structured Abstract Background Ostomy surgery is common and has traditionally been associated with high rates of morbidity and mortality, suggesting an important target for quality improvement. Objective To evaluate the variation in outcomes after ostomy creation surgery within Michigan in order to identify targets for quality improvement. Design Retrospective cohort study. Setting The 34-hospital Michigan Surgical Quality Collaborative (MSQC). Patients Patients undergoing ostomy creation surgery between 2006-2011. Main outcome measures We evaluated hospitals' morbidity and mortality rates after risk-adjustment (age, comorbidities, emergency v. elective, procedure type). Results 4,250 patients underwent ostomy creation surgery; 3,866 (91.0%) procedures were open and 384 (9.0%) were laparoscopic. Unadjusted morbidity and mortality rates were 43.9% and 10.7%, respectively. Unadjusted morbidity rates for specific procedures ranged from 32.7% for ostomy-creation-only procedures to 47.8% for Hartmann's procedures. Risk-adjusted morbidity rates varied significantly between hospitals, ranging from 31.2% (95%CI 18.4-43.9) to 60.8% (95%CI 48.9-72.6). There were five statistically-significant high-outlier hospitals and three statistically-significant low-outlier hospitals for risk-adjusted morbidity. The pattern of complication types was similar between high- and low-outlier hospitals. Case volume, operative duration, and use of laparoscopic surgery did not explain the variation in morbidity rates across hospitals. Conclusions Morbidity and mortality rates for modern ostomy surgery are high. While this type of surgery has received little attention in healthcare policy, these data reveal that it is both common and uncommonly morbid. Variation in hospital performance provides an opportunity to identify quality improvement practices that could be disseminated among hospitals. PMID:24819104

The influence of proton pump inhibitors and other commonly used medication on the gut microbiota.

PubMed

Imhann, Floris; Vich Vila, Arnau; Bonder, Marc Jan; Lopez Manosalva, Ailine G; Koonen, Debby P Y; Fu, Jingyuan; Wijmenga, Cisca; Zhernakova, Alexandra; Weersma, Rinse K

2017-07-04

Proton pump inhibitors (PPIs), used to treat gastro-esophageal reflux and prevent gastric ulcers, are among the most widely used drugs in the world. The use of PPIs is associated with an increased risk of enteric infections. Since the gut microbiota can, depending on composition, increase or decrease the risk of enteric infections, we investigated the effect of PPI-use on the gut microbiota. We discovered profound differences in the gut microbiota of PPI users: 20% of their bacterial taxa were statistically significantly altered compared with those of non-users. Moreover, we found that it is not only PPIs, but also antibiotics, antidepressants, statins and other commonly used medication were associated with distinct gut microbiota signatures. As a consequence, commonly used medications could affect how the gut microbiota resist enteric infections, promote or ameliorate gut inflammation, or change the host's metabolism. More studies are clearly needed to understand the role of commonly used medication in altering the gut microbiota as well as the subsequent health consequences.

Agreement between Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and the proposed DSM-V attention deficit hyperactivity disorder diagnostic criteria: an exploratory study.

PubMed

Ghanizadeh, Ahmad

2013-01-01

There is no empirical literature about the American Psychiatry Association proposed new diagnostic criteria for attention deficit hyperactivity disorder (ADHD). This study examined the agreement between ADHD diagnosis derived from Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), and DSM-V diagnostic criteria. It also reports sensitivity, specificity, and agreement for ADHD diagnosis. A clinical sample of 246 children and adolescents were interviewed face to face using both ADHD diagnostic criteria for DSM-V and DSM-IV by interviewing clinician. Comorbid psychiatric disorders were screened using DSM-IV criteria. The rate of ADHD diagnosis using DSM-V was significantly higher than the rate detected by using DSM-IV diagnostic criteria. The sensitivity of DSM-V diagnostic criteria was 100%, while its specificity was 71.1%. The kappa agreement between DSM-IV and DSM-V was 0.75. In addition, positive predictive value was 85.1%. All the four newly added symptoms to ADHD diagnostic criteria are statistically more common in the children with ADHD than those in the comparison group. However, these symptoms are also very common in the children without ADHD. It is expected that the rate of ADHD would increase using the proposed ADHD DSM-V criteria. Moreover, the newly added symptoms have a low specificity for ADHD diagnosis. Copyright © 2013 Elsevier Inc. All rights reserved.

Towards a web-based decision support tool for selecting appropriate statistical test in medical and biological sciences.

PubMed

Suner, Aslı; Karakülah, Gökhan; Dicle, Oğuz

2014-01-01

Statistical hypothesis testing is an essential component of biological and medical studies for making inferences and estimations from the collected data in the study; however, the misuse of statistical tests is widely common. In order to prevent possible errors in convenient statistical test selection, it is currently possible to consult available test selection algorithms developed for various purposes. However, the lack of an algorithm presenting the most common statistical tests used in biomedical research in a single flowchart causes several problems such as shifting users among the algorithms, poor decision support in test selection and lack of satisfaction of potential users. Herein, we demonstrated a unified flowchart; covers mostly used statistical tests in biomedical domain, to provide decision aid to non-statistician users while choosing the appropriate statistical test for testing their hypothesis. We also discuss some of the findings while we are integrating the flowcharts into each other to develop a single but more comprehensive decision algorithm.

Putting Meaning Back Into the Mean: A Comment on the Misuse of Elementary Statistics in a Sample of Manuscripts Submitted to Clinical Therapeutics.

PubMed

Forrester, Janet E

2015-12-01

Errors in the statistical presentation and analyses of data in the medical literature remain common despite efforts to improve the review process, including the creation of guidelines for authors and the use of statistical reviewers. This article discusses common elementary statistical errors seen in manuscripts recently submitted to Clinical Therapeutics and describes some ways in which authors and reviewers can identify errors and thus correct them before publication. A nonsystematic sample of manuscripts submitted to Clinical Therapeutics over the past year was examined for elementary statistical errors. Clinical Therapeutics has many of the same errors that reportedly exist in other journals. Authors require additional guidance to avoid elementary statistical errors and incentives to use the guidance. Implementation of reporting guidelines for authors and reviewers by journals such as Clinical Therapeutics may be a good approach to reduce the rate of statistical errors. Copyright © 2015 Elsevier HS Journals, Inc. All rights reserved.

Luteal phase bleeding after IVF cycles: comparison between progesterone vaginal gel and intramuscular progesterone and correlation with pregnancy outcomes

PubMed Central

Jabara, Sami; Barnhart, Kurt; Schertz, Joan C; Patrizio, Pasquale

2009-01-01

Background: To compare luteal phase bleeding and pregnancy outcomes in normogonadotropic patients receiving progesterone vaginal gel (PVG) or intramuscular progesterone (IMP) injections. Methods: In this retrospective cohort study, data from 270 patients (292 cycles) undergoing day-3 fresh embryo transfer were analyzed. PVG, 90 mg daily (170 cycles) or IMP, 50 mg daily (122 cycles) began at egg retrieval. Results: Luteal phase bleeding was significantly more common in the PVG than the IMP group. No significant differences were observed in biochemical pregnancy or spontaneous abortion rates between the two groups. Patients who bled before the pregnancy test had significantly lower total and clinical pregnancy rates than non-bleeders. Total and ongoing pregnancy/delivery rates were higher in the PVG than IMP group, but did not achieve statistical significance. Conclusion: Luteal phase bleeding was more common in the PVG group than the IMP group, but pregnancy was successful in more patients in the PVG group. Luteal phase bleeding is prevented or delayed during IMP treatment, but patients who bled before the pregnancy test, whether using the gel or injected progesterone, had significantly reduced pregnancy rates compared with non-bleeders. PMID:20485581

Is there a relationship between obesity and intracranial hypertension?

PubMed

Hannerz, J; Greitz, D; Ericson, K

1995-04-01

Intracranial hypertension and obesity have been reported in recent studies of patients with periorbital venous vasculitis. These findings indicate that obese patients should be investigated for signs of inflammation in serum and lumbar cerebrospinal fluid (CSF) pressure. Twenty obese females, aged 27-68 years participated in the study of associated symptoms, signs of inflammation in serum, intracranial hypertension and magnetic resonance imaging of the brain (MR). Twenty randomly selected age- and sex-matched females were also investigated for associated symptoms and MR as controls. There were no statistically significant differences in associated symptoms and diseases except for infertility (P < 0.05) between the two groups. The values for orosomucoid, haptoglobin, IgG, IgM and tests for rheumatic and antinuclear factors were significantly increased in the obese group compared with normal values at the hospital. The lumbar CSF pressure was increased above 20 cm water in 79% and above 25 cm water in 42% in the obese patients. MR showed that the subarachnoidal space in the obese patients were significantly smaller than in the controls. Signs of inflammation in serum, intracranial hypertension and decreased subarachnoidal space were statistically significantly more common in patients with obesity, than in controls.

Clinical features and risk factor analysis for lower extremity deep venous thrombosis in Chinese neurosurgical patients

PubMed Central

Guo, Fuyou; Shashikiran, Tagilapalli; Chen, Xi; Yang, Lei; Liu, Xianzhi; Song, Laijun

2015-01-01

Background: Deep venous thrombosis (DVT) contributes significantly to the morbidity and mortality of neurosurgical patients; however, no data regarding lower extremity DVT in postoperative Chinese neurosurgical patients have been reported. Materials and Methods: From January 2012 to December 2013, 196 patients without preoperative DVT who underwent neurosurgical operations were evaluated by color Doppler ultrasonography and D-dimer level measurements on the 3rd, 7th, and 14th days after surgery. Follow-up clinical data were recorded to determine the incidence of lower extremity DVT in postoperative neurosurgical patients and to analyze related clinical features. First, a single factor analysis, Chi-square test, was used to select statistically significant factors. Then, a multivariate analysis, binary logistic regression analysis, was used to determine risk factors for lower extremity DVT in postoperative neurosurgical patients. Results: Lower extremity DVT occurred in 61 patients, and the incidence of DVT was 31.1% in the enrolled Chinese neurosurgical patients. The common symptoms of DVT were limb swelling and lower extremity pain as well as increased soft tissue tension. The common sites of venous involvement were the calf muscle and peroneal and posterior tibial veins. The single factor analysis showed statistically significant differences in DVT risk factors, including age, hypertension, smoking status, operation time, a bedridden or paralyzed state, the presence of a tumor, postoperative dehydration, and glucocorticoid treatment, between the two groups (P < 0.05). The binary logistic regression analysis showed that an age greater than 50 years, hypertension, a bedridden or paralyzed state, the presence of a tumor, and postoperative dehydration were risk factors for lower extremity DVT in postoperative neurosurgical patients. Conclusions: Lower extremity DVT was a common complication following craniotomy in the enrolled Chinese neurosurgical patients. Multiple factors were identified as predictive of DVT in neurosurgical patients, including the presence of a tumor, an age greater than 50 years, hypertension, and immobility. PMID:26752303

A prospective study of two methods of closing surgical scalp wounds.

PubMed

Adeolu, A A; Olabanji, J K; Komolafe, E O; Ademuyiwa, A O; Awe, A O; Oladele, A O

2012-02-01

Scalp wounds are commonly closed in two layers, although single layer closure is feasible. This study prospectively compared the two methods of closing scalp wounds. Patients with non-traumatic scalp wounds were allocated to either the single layer closure group or the multilayer closure group. We obtained relevant data from the patients. The primary outcome measures were wound edge related complications, rate of suturing and cost of sutures used for suturing. Thirty-one wounds were in the single layer closure group and 30 were in the multilayer closure group. Age range was 1-80 years. The most common indication for making a scalp incision was subdural hematoma, representing 27.8% of all the indications. The most common surgery was burr hole drainage of subdural hematoma. Polyglactin acid suture was used for the inner layer and polyamide -00- for the final layer in the multilayer closure group. Only the latter suture was used for the single layer closure method. Total cost of suturing per wound in the single layer closure group was N= 100 (0.70USD) and N= 800 (5.30USD) in the multilayer group. The mean rate of closure was 0.39 ± 1.89 mm/sec for single layer closure and 0.23 ± 0.89 mm/sec in multilayer closure. The difference was statistically significant. Wound edge related complication rate was 19.35% in the single layer closure group and 16.67% in the multilayer closure method group. The difference was not statistically significant (z: 0.00, p value: 1.000; Pearson chi-squared (DF = 1)= 0.0075, p = 0.0785). The study shows that closing the scalp in one layer is much faster and more cost effective compared to the multilayer closure method. We did not observe significant difference in the complication rates in the two methods of closure. Long-term outcome, especially cosmetic outcome, remains to be determined in this preliminary study.

Regression: The Apple Does Not Fall Far From the Tree.

PubMed

Vetter, Thomas R; Schober, Patrick

2018-05-15

Researchers and clinicians are frequently interested in either: (1) assessing whether there is a relationship or association between 2 or more variables and quantifying this association; or (2) determining whether 1 or more variables can predict another variable. The strength of such an association is mainly described by the correlation. However, regression analysis and regression models can be used not only to identify whether there is a significant relationship or association between variables but also to generate estimations of such a predictive relationship between variables. This basic statistical tutorial discusses the fundamental concepts and techniques related to the most common types of regression analysis and modeling, including simple linear regression, multiple regression, logistic regression, ordinal regression, and Poisson regression, as well as the common yet often underrecognized phenomenon of regression toward the mean. The various types of regression analysis are powerful statistical techniques, which when appropriately applied, can allow for the valid interpretation of complex, multifactorial data. Regression analysis and models can assess whether there is a relationship or association between 2 or more observed variables and estimate the strength of this association, as well as determine whether 1 or more variables can predict another variable. Regression is thus being applied more commonly in anesthesia, perioperative, critical care, and pain research. However, it is crucial to note that regression can identify plausible risk factors; it does not prove causation (a definitive cause and effect relationship). The results of a regression analysis instead identify independent (predictor) variable(s) associated with the dependent (outcome) variable. As with other statistical methods, applying regression requires that certain assumptions be met, which can be tested with specific diagnostics.

Occupationally related contact dermatitis in North American food service workers referred for patch testing, 1994 to 2010.

PubMed

Warshaw, Erin M; Kwon, Gina P; Mathias, C G Toby; Maibach, Howard I; Fowler, Joseph F; Belsito, Donald V; Sasseville, Denis; Zug, Kathryn A; Taylor, James S; Fransway, Anthony F; Deleo, Vincent A; Marks, James G; Pratt, Melanie D; Storrs, Frances J; Zirwas, Matthew J; Dekoven, Joel G

2013-01-01

Contact dermatoses are common in food service workers (FSWs). This study aims to (1) determine the prevalence of occupationally related contact dermatitis among FSWs patch tested by the North American Contact Dermatitis Group (NACDG) and (2) characterize responsible allergens and irritants as well as sources. Cross-sectional analysis of patients patch tested by the NACDG, 1994 to 2010, was conducted. Of 35,872 patients patch tested, 1237 (3.4%) were FSWs. Occupationally related skin disease was significantly more common in FSWs when compared with employed non-FSWs. Food service workers were significantly more likely to have hand (P < 0.0001) and arm (P < 0.0006) involvement. The rates for irritant and allergic contact dermatitis in FSWs were 30.6% and 54.7%, respectively. Although the final diagnosis of irritant contact dermatitis was statistically higher in FSWs as compared with non-FSWs, allergic contact dermatitis was lower in FSWs as compared with non-FSWs. The most frequent currently relevant and occupationally related allergens were thiuram mix (32.5%) and carba mix (28.9%). Gloves were the most common source of responsible allergens. The NACDG standard tray missed at least 1 occupationally related allergen in 38 patients (4.3%). Among FSWs patch tested by the NACDG between 1994 and 2010, the most common allergens were thiuram mix and carba mix. Gloves were the most common source of responsible allergens.

Safety and efficacy of endoscopic retrograde cholangiopancreatography for common bile duct stones in liver cirrhotic patients.

PubMed

Li, De-min; Zhao, Jie; Zhao, Qiu; Qin, Hua; Wang, Bo; Li, Rong-xiang; Zhang, Min; Hu, Ji-fen; Yang, Min

2014-08-01

In order to investigate the safety and efficacy of endoscopic retrograde cholangiopancreatograpy (ERCP) in liver cirrhosis patients with common bile duct stones, we retrospectively analyzed data of 46 common bile duct stones patients with liver cirrhosis who underwent ERCP between 2000 and 2008. There were 12 cases of Child-Pugh A, 26 cases of Child-Pugh B, and 8 cases of Child-Pugh C. 100 common bile duct stones patients without liver cirrhosis were randomly selected. All the patients were subjected to ERCP for biliary stones extraction. The rates of bile duct clearance and complications were compared between cirrhotic and non-cirrhotic patients. The success rate of selective biliary cannulation was 95.6% in liver cirrhotic patients versus 97% in non-cirrhotic patients (P>0.05). The bile duct clearance rate was 87% in cirrhotic patients versus 96% in non-cirrhotic patients, but the difference was not statistically significant. Two liver cirrhotic patients (4.35%, 2/46) who were scored Child-Pugh C had hematemesis and melena 24 h after ERCP. The hemorrhage rate after ERCP in non-cirrhotic patients was 3%. The hemorrhage rate associated with ERCP in Child-Pugh C patients was significantly higher (25%, 2/8) than that (3%, 3/100) in non-cirrhotic patients (P<0.01%). There was no significant difference between these two groups in the rate of post-ERCP pancreatitis (PEP) and cholangitis. ERCP is safe and effective for Child-Pugh A and B cirrhotic patients with common bile duct stones. Hemorrhage risk in ERCP is higher in Child-Pugh C patients.

The Role of Gender in Neuropsychological Assessment in Healthy Adolescents.

PubMed

Mormile, Megan Elizabeth Evelyn; Langdon, Jody L; Hunt, Tamerah Nicole

2018-01-01

Research in college athletes has revealed significant gender differences in areas of verbal memory, visual memory, and reaction time. Additionally, research has focused on differences in neuropsychological components and gender in college populations; however, such differences in gender have not been documented in healthy adolescent populations. To identify potential differences between males and females using different components of a common computerized neuropsychological test. A computerized neuropsychological test battery (ImPACT®) was administered to 662 high-school age adolescent athletes (male: n = 451 female: n = 262). Differences between genders were calculated using a 1-way ANOVA. All statistical analyses were conducted using SPSS 23.0. Significance levels were set a priori at P < .05. A 1-way ANOVA revealed statistically significant differences between males and females for composite reaction time (F 1,660  = 10.68, P = .001) and total symptom score (F 1,660  = 81.20, P < .001). However, no statistically significant differences were found between males and females in composite verbal memory, visual memory, visual motor, or impulse control (P > .05). Significant differences between males and females were discovered for composite reaction time and total symptom scores, with females reporting more symptoms and slower reaction times at a baseline assessment. Increased symptom reporting by females may be attributed to both hormonal differences and increased honesty. Quicker reaction times in males may support theories that repetition of activities and quicker muscle contraction are gender dependent. However, additional research is necessary to understand gender differences in adolescent athletes during periods of cognitive and physical maturation.

Gripe Water Administration in Infants 1-6 months of Age-A Cross-sectional Study.

PubMed

Jain, Keerthi; Gunasekaran, Dhandapany; Venkatesh, Chandrasekaran; Soundararajan, Palanisamy

2015-11-01

Gripe water (GW) administration to young infants is common practice in this part of country. In order to ascertain why mothers administer gripe water to their infants and to find out what benefits or health risks it poses, we proposed to study the practice of mothers giving GW to their babies. Three hundred and thirty five eligible mothers of infants aged 1-6 months (who after qualifying inclusion and exclusion criteria of the study) who attended the well baby clinic during the study period, were interviewed using a semi structured questionnaire which contained both open and close ended questions after obtaining informed written consent. The study population was then divided into two groups based on administration of GW or not and the results were compared and analysed among the two groups using odds ratio with 95% C.I. For calculation of statistics, the statistical package SPSS 13 was used. 64.18% of the mothers were administering GW for their infants. Most mothers believed that GW helps in digestion and prevents stomach ache. Infantile colic, vomiting and constipation were common in GW administered infants, when compared to those who did not receive GW and the difference was significant with p-values of 0.0001, 0.0373, 0.0007respectively. GW administration is a common problem in infants and remains a significant challenge that thwarts exclusive breast feeding. More over GW administration does not seem to prevent infantile colic and on the other hand, may be associated with vomiting and constipation. Misconceptions prevailing among mothers have to be removed by effective counseling so that the mothers are aware of safe and healthy feeding practices to be adopted for feeding their babies.

P value and the theory of hypothesis testing: an explanation for new researchers.

PubMed

Biau, David Jean; Jolles, Brigitte M; Porcher, Raphaël

2010-03-01

In the 1920s, Ronald Fisher developed the theory behind the p value and Jerzy Neyman and Egon Pearson developed the theory of hypothesis testing. These distinct theories have provided researchers important quantitative tools to confirm or refute their hypotheses. The p value is the probability to obtain an effect equal to or more extreme than the one observed presuming the null hypothesis of no effect is true; it gives researchers a measure of the strength of evidence against the null hypothesis. As commonly used, investigators will select a threshold p value below which they will reject the null hypothesis. The theory of hypothesis testing allows researchers to reject a null hypothesis in favor of an alternative hypothesis of some effect. As commonly used, investigators choose Type I error (rejecting the null hypothesis when it is true) and Type II error (accepting the null hypothesis when it is false) levels and determine some critical region. If the test statistic falls into that critical region, the null hypothesis is rejected in favor of the alternative hypothesis. Despite similarities between the two, the p value and the theory of hypothesis testing are different theories that often are misunderstood and confused, leading researchers to improper conclusions. Perhaps the most common misconception is to consider the p value as the probability that the null hypothesis is true rather than the probability of obtaining the difference observed, or one that is more extreme, considering the null is true. Another concern is the risk that an important proportion of statistically significant results are falsely significant. Researchers should have a minimum understanding of these two theories so that they are better able to plan, conduct, interpret, and report scientific experiments.

The Effect of Adjuvant Zinc Therapy on Recovery from Pneumonia in Hospitalized Children: A Double-Blind Randomized Controlled Trial

PubMed Central

Qasemzadeh, Mohammad Javad; Fathi, Mahdi; Tashvighi, Maryam; Gharehbeglou, Mohammad; Yadollah-Damavandi, Soheila; Parsa, Yekta; Rahimi, Ebrahim

2014-01-01

Objectives. Pneumonia is one of the common mortality causes in young children. Some studies have shown beneficial effect of zinc supplements on treatment of pneumonia. The present study aimed to investigate the effects of short courses of zinc administration on recovery from this disease in hospitalized children. Methods. In a parallel Double-Blind Randomized Controlled Trial at Ayatollah Golpaygani Hospital in Qom, 120 children aged 3–60 months with pneumonia were randomly assigned 1 : 1 to receive zinc or placebo (5 mL every 12 hours) along with the common antibiotic treatments until discharge. Primary outcome was recovery from pneumonia which included the incidence and resolving clinical symptoms and duration of hospitalization. Results. The difference between two groups in all clinical symptoms at admittance and the variables affecting the disease such as age and sex were not statistically significant (P < 0.05) at baseline. Compared to the placebo group, the treatment group showed a statistically significant decrease in duration of clinical symptoms (P = 0.044) and hospitalization (P = 0.004). Conclusions. Supplemental administration of zinc can expedite the healing process and results in faster resolution of clinical symptoms in children with pneumonia. In general, zinc administration, along with common antibiotic treatments, is recommended in this group of children. It can also reduce the drug resistance caused by multiple antibiotic therapies. This trial is approved by Medical Ethic Committee of Islamic Azad University in Iran (ID Number: 8579622-Q). This study is also registered in AEARCTR (The American Economic Association's Registry for Randomized Controlled Trials). This trial is registered with RCT ID: AEARCTR-0000187. PMID:24955282

Primary closure versus T-tube drainage in laparoscopic common bile duct exploration: a meta-analysis of randomized clinical trials.

PubMed

Wu, Xiangsong; Yang, Yong; Dong, Ping; Gu, Jun; Lu, Jianhua; Li, Maolan; Mu, Jiasheng; Wu, Wenguang; Yang, Jiahua; Zhang, Lin; Ding, Qichen; Liu, Yingbin

2012-08-01

To compare the safety and effectiveness of primary closure with those of T-tube drainage in laparoscopic common bile duct exploration (LCBDE) for choledocholithiasis. A comprehensive search was performed in the PubMed, EmBase, and Cochrane Library databases. Only randomized controlled trials comparing primary closure with T-tube drainage in LCBDE were considered eligible for this meta-analysis. The analyzed outcome variables included postoperative mortality, overall morbidity, biliary complication rate, biliary leak rate, reoperation, operating time, postoperative hospital stay, time to abdominal drain removal, and retained stone. All calculations and statistical tests were performed using ReviewerManager 5.1.2 software. A total of 295 patients (148 patients with primary closure and 147 patients with T-tube drainage) from three trials were identified and analyzed. No deaths occurred in any of the trials. Primary closure showed significantly better results in terms of morbidity (risk ratio (RR), 0.51; 95% confidence interval (CI), 0.30 to 0.88), biliary complication without a combination of retained stone (RR, 0.44; 95% CI, 0.20 to 0.97), reoperation (RR, 0.16; 95% CI, 0.03 to 0.87), operating time (mean difference (MD), -20.72; 95% CI, -29.59 to -11.85), postoperative hospital stay (MD, -3.24; 95% CI, -3.96 to -2.52), and time to abdominal drainage removal (MD, -0.45; 95% CI, -0.86 to -0.04). Statistically significant differences were not found between the two methods in terms of biliary leak, biliary complication, and retained stones. The current meta-analysis indicates that primary closure of the common bile duct is safer and more effective than T-tube drainage for LCBDE. Therefore, we do not recommend routine performance of T-tube drainage in LCBDE.

Yield of coeliac screening in abdominal pain-associated functional gastrointestinal system disorders.

PubMed

Kansu, Aydan; Kuloğlu, Zarife; Demir, Arzu; Yaman, Aytaç

2015-11-01

Chronic abdominal pain (CAP) in childhood is common and in the majority functional. While CAP is one of the complaints of coeliac disease (CD), whether CAP as a sole complaint is indicative of CD is unclear. Our aim was to evaluate the relationship between CAP and CD. The study was conducted on 1047 children (61.1% female, mean age 9.6 ± 4.1 years) with CAP. Patients were evaluated according to the Rome III criteria. Patients with alarm symptoms and conditions known to be associated with CD were excluded. Patients were screened for CD using a rapid tissue transglutaminase (tTG) test; positive cases were tested by tTG ELISA, and duodenal biopsies were obtained if tTG was above the normal limit. Functional dyspepsia (FD), irritable bowel syndrome (IBS) and functional abdominal pain (FAP) were diagnosed in 384 (36.7%), 274 (26.2%) and 389 (37.2%) patients, respectively. In 13 patients, the tTG rapid test was positive; 10 were also positive for tTG by ELISA and histopathological evaluations diagnosed CD in all 10 patients. The overall prevalence of CD was 0.95% (2.2%, 0.5% and 0.5% in patients with IBS, FD and FAP, respectively). The prevalence of CD in patients with IBS was higher than expected but with borderline statistical significance (P = 0.053). CD is found as common in children with FD and FAP as in the general population. CD was more commonly diagnosed in IBS patients with borderline statistical significance. We suggest that particular attention be paid to children with IBS. © 2015 The Authors. Journal of Paediatrics and Child Health © 2015 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

FACTORS RELATED TO ORAL CANDIDIASIS IN ELDERLY USERS AND NON-USERS OF REMOVABLE DENTAL PROSTHESES.

PubMed

Bianchi, Cyra Maria Pires de Carvalho; Bianchi, Hélcio Aparecido; Tadano, Tomoko; Paula, Claudete Rodrigues de; Hoffmann-Santos, Hugo Dias; Leite, Diniz Pereira; Hahn, Rosane Christine

2016-01-01

This study examined the association between oral candidiasis in elderly users and nonusers of prosthesis and its predisposing factors. To this end, we performed a cross-sectional study where saliva samples from 48 patients were collected they used prosthesis and 43 patients (control group) who did not use. Among the 91 patients, Candida spp were isolated in 40 (83.3%) who used prosthesis and in 23 (53.5%) in the control group. A statistically significant association was determined between the two groups, the isolation of yeasts and dental prosthesis (p < 0.05, OR = 4.3). The most common etiological agent was Candida albicans (37 isolates), with 23 (62.2%) in the denture group and 14 (37.8%) (control group). Among patients who presented clinical manifestations of oral candidiasis (n = 24), 83.3% (n = 20) belonged to the group that wore dentures, while only 16.7% (n = 4) belonged to the control group. Elderly patients with diabetes had 4.4 times higher estimated risk of developing oral candidiasis when compared with individuals without this condition. There was no statistically significant association between being user prostheses and have diabetes with the onset of candidiasis. No statistically significant association was determined between xerostomia, use of prosthesis and oral candidiasis. The use of prosthetics and poor oral hygiene in elderly patients predisposes to the development of oral candidiasis.

Mental health benefits of interactions with nature in children and teenagers: a systematic review.

PubMed

Tillmann, Suzanne; Tobin, Danielle; Avison, William; Gilliland, Jason

2018-06-27

It is commonly believed that nature has positive impacts on children's health, including physical, mental and social dimensions. This review focuses on how accessibility to, exposure to and engagement with nature affects the mental health of children and teenagers. Ten academic databases were used to systematically search and identify primary research papers in English or French from 1990 to 1 March 2017. Papers were included for review based on their incorporation of nature, children and teenagers (0-18 years), quantitative results and focus on mental health. Of the 35 papers included in the review, the majority focused on emotional well-being and attention deficit disorder/hyperactivity disorder. Other outcome measures included overall mental health, self-esteem, stress, resilience, depression and health-related quality of life. About half of all reported findings revealed statistically significant positive relationships between nature and mental health outcomes and almost half reported no statistical significance. Findings support the contention that nature positively influences mental health; however, in most cases, additional research with more rigorous study designs and objective measures of both nature and mental health outcomes are needed to confirm statistically significant relationships. Existing evidence is limited by the cross-sectional nature of most papers. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

[Mobile geriatric consultant services for rest homes. Study of the effects of consultations by internal medicine specialists in the medical care of rest home residents].

PubMed

Schippinger, W; Hartinger, G; Hierzer, A; Osprian, I; Bohnstingl, M; Pilgram, E H

2012-12-01

Hospital admissions are frequent among long-term residents of nursing homes and can result in detrimental complications affecting the patients' somatic, psychological, and cognitive status. In this prospective controlled study, we investigated the effects of a mobile geriatric consultant service (GECO) offered by specialists in internal medicine on frequency of hospitalizations in nursing home residents. During a 10-month observation period, residents in a control nursing home received medical attendance by general practitioners as is common in Austrian nursing homes. Residents in the intervention nursing home also received the medical service of GECO. Within the group of rest home residents receiving GECO support, a statistically significant lower frequency of acute transports to hospitals was observed in comparison to residents of the control nursing home (mean number of acute transports to hospitals/100 residents/month: 6.1 versus 11.7; p < 0.01). The number of planned non-acute hospital and specialist office presentations was also lower in the intervention nursing home (mean number of hospital and specialist office presentations/100 residents/month: 14.4 versus 18.0); however, this difference did not reach statistical significance. This study shows that a mobile medical geriatric consultant service based on specialists in internal medicine can improve medical care in nursing homes resulting in a statistically significant reduction of acute transports to hospitals.

FACTORS RELATED TO ORAL CANDIDIASIS IN ELDERLY USERS AND NON-USERS OF REMOVABLE DENTAL PROSTHESES

PubMed Central

BIANCHI, Cyra Maria Pires de Carvalho; BIANCHI, Hélcio Aparecido; TADANO, Tomoko; de PAULA, Claudete Rodrigues; HOFFMANN-SANTOS, Hugo Dias; LEITE, Diniz Pereira; HAHN, Rosane Christine

2016-01-01

This study examined the association between oral candidiasis in elderly users and nonusers of prosthesis and its predisposing factors. To this end, we performed a cross-sectional study where saliva samples from 48 patients were collected they used prosthesis and 43 patients (control group) who did not use. Among the 91 patients, Candida spp were isolated in 40 (83.3%) who used prosthesis and in 23 (53.5%) in the control group. A statistically significant association was determined between the two groups, the isolation of yeasts and dental prosthesis (p < 0.05, OR = 4.3). The most common etiological agent was Candida albicans (37 isolates), with 23 (62.2%) in the denture group and 14 (37.8%) (control group). Among patients who presented clinical manifestations of oral candidiasis (n = 24), 83.3% (n = 20) belonged to the group that wore dentures, while only 16.7% (n = 4) belonged to the control group. Elderly patients with diabetes had 4.4 times higher estimated risk of developing oral candidiasis when compared with individuals without this condition. There was no statistically significant association between being user prostheses and have diabetes with the onset of candidiasis. No statistically significant association was determined between xerostomia, use of prosthesis and oral candidiasis. The use of prosthetics and poor oral hygiene in elderly patients predisposes to the development of oral candidiasis. PMID:27007560

Influence of two different surgical techniques on the difficulty of impacted lower third molar extraction and their post-operative complications.

PubMed

Mavrodi, Alexandra; Ohanyan, Ani; Kechagias, Nikos; Tsekos, Antonis; Vahtsevanos, Konstantinos

2015-09-01

Post-operative complications of various degrees of severity are commonly observed in third molar impaction surgery. For this reason, a surgical procedure that decreases the trauma of bone and soft tissues should be a priority for surgeons. In the present study, we compare the efficacy and the post-operative complications of patients to whom two different surgical techniques were applied for impacted lower third molar extraction. Patients of the first group underwent the classical bur technique, while patients of the second group underwent another technique, in which an elevator was placed on the buccal surface of the impacted molar in order to luxate the alveolar socket more easily. Comparing the two techniques, we observed a statistically significant decrease in the duration of the procedure and in the need for tooth sectioning when applying the second surgical technique, while the post-operative complications were similar in the two groups. We also found a statistically significant lower incidence of lingual nerve lesions and only a slightly higher frequency of sharp mandibular bone irregularities in the second group, which however was not statistically significant. The results of our study indicate that the surgical technique using an elevator on the buccal surface of the tooth seems to be a reliable method to extract impacted third molars safely, easily, quickly and with the minimum trauma to the surrounding tissues.

[Nursing intervention and evaluation of postoperative pain in preschool children with cleft lip and palate].

PubMed

Gong, Caixia; Yan, Miao; Jiang, Fei; Chen, Zehua; Long, Yuan; Chen, Lixian; Zheng, Qian; Shi, Bing

2014-06-01

This study aimed to observe the postoperative pain rate and degree of pain in preschool children with cleft lip and palate, and investigate the effect of nursing intervention on pain relief. A total of 120 hospitalized cases of three- to seven-year-old preschool children with cleft lip and palate were selected from May to October 2011. The subjects were randomly divided into the control group and experimental groups 1, 2, and 3. The control group used conventional nursing methods, experimental group 1 used analgesic drug treatment, experimental group 2 used psychological nursing interventions, and experimental group 3 used both psychological nursing intervention and analgesic drug treatment. After 6, 12, 24, and 48 h, pain self-assessment, pain parent-assessment, and pain nurse-assessment were calculated for the four groups using the pain assessment forms, and their ratings were compared. The postoperative pain rates of the four groups ranged from 50.0% to 73.3%. The difference among the four groups was statistically significant (P < 0.001). The differences among the control group and experimental groups 1 and 2 were not statistically significant (P = 0.871), whereas the differences among experimental group 3 and the other groups were statistically significant (P < 0.001). Postoperative pain in preschool children with cleft lip and palate is common. Psychological nursing intervention with analgesic treatment is effective in relieving postoperative pain.

[Clinical profile of cytomegalovirus (CMV) enterocolitis in acquired immunodeficiency syndrome].

PubMed

De Lima, D B; Fernandes, O; Gomes, V R; Da Silva, E J; De Pinho, P R; De Paiva, D D

2000-01-01

To determine the clinical profile of CMV colitis in AIDS patients, comparing clinical, endoscopic parameters and survival time between 2 groups of AIDS patients having chronic diarrhea. Group A being CMV colitis and group B without CMV colitis. 48 patients with diarrhea that lasted more than 30 days, being 27 in Group A and 21 in Group B, were studied. Age, risk factors, interval time between the diagnosis of HIV infection and the beginning of diarrhea, hematochesia, the endoscopic findings and life table in both groups, were analysed. All of them were diagnosed by stool culture and stools for ovum and parasites, along colonoscopy with biopsies. The unpaired t test was used to assess statistical significance of differences observed in the means of continuous and the chi-square with Yates correction for non-parametric variables. The survival curves were assessed by the Kaplan-Meier and the Mantel-Haenszel's tests. A P value of less than 0,05 was considered to indicate statistical significance. The mucosal lesions associated with the CMV infection are typically ulcerative on a background of hemorrhagic erythema 14 (51,8%) p < 0,01. The life table analysis disclosed shorter survival time in the CMV colitis group 0,005> P>0,001. The others studied data did not achieve statistical significance. AIDS patients with CMV colitis have a poorer long-term survival. Among the colonoscopic findings, ulcerations with hemorrhagic background were the most common lesions.

Quality of Life of Patients with Oral Cavity Cancer.

PubMed

Dzebo, Senada; Mahmutovic, Jasmina; Erkocevic, Hasiba

2017-03-01

In recent years the quality of life of patients is very important in monitoring the treatment and therapeutic procedure success. It has become a significant factor in assessing the therapeutic procedure accomplishment, and for the first time the patient alone can access the success of the respective therapy. Cancer of the oral cavity is one of the most common cancers of the head and neck, and is one of the ten most common causes of death in the world. In the majority of cases, cancer of the oral cavity is detected in an advanced stage when therapeutic options are reduced, and the prognosis is much worse. Cancer of the oral cavity is 10 times more common in men. Assessment of quality of life should be an indicator of the multidisciplinary treatment success and it should point to areas in which the affected person requires support. To examine the quality of life of patients with oral cavity cancer. The study was conducted at the Clinic of Maxillofacial Surgery of the Clinical Center University of Sarajevo (CCUS), through a survey on patients with verified oral cavity cancer, questionnaire related to socio-demographic characteristics of the patients and the University of Washington Quality of Life Questionnaire (UW-QOL). The results were included in the database and statistically processed in the SPSS program, 19.0 version for Windows. Afterwards, the results were thoroughly analyzed and documented, presented in absolute numbers and statistical values using statistical indicators in simple and understandable tables and figures. The study results showed that out of the total score of 100, the median value of quality of life of patients with oral cavity cancer, for the physical health component in the definition of quality was M=69.75 ±29.12 and for social-emotional health M=65.11 ± 27.47. This could be considered as satisfactory quality of life, in the sphere above half of the rating scale, although both values significantly deviate from the UW-QOL scale norm. Physical and socio-emotional health components are in a strong positive correlation, R 2 =0.750, p=0.0001.

Diagnostic Factors of Odontogenic Cysts in Iranian Population: A Retrospective Study Over the Past Two Decades.

PubMed

Mohajerani, Hassan; Esmaeelinejad, Mohammad; Sabour, Siamak; Aghdashi, Farzad; Dehghani, Nima

2015-06-01

Early diagnosis of odontogenic cysts due to their silent progression is always a challenging problem for clinicians. The current study aimed to evaluate the frequency of odontogenic cysts and related factors in a selected Iranian population. The current cross-sectional study was conducted on 312 patients' recorded data in Taleghani Hospital, Tehran, Iran, from April 1993 to December 2013. All related data were extracted from the records and categorized in tables. The correlation between the variables was analyzed by either chi-square or multinominal logistic regression tests. The P values < 0.05 were considered significant. Evaluation of 312 patients' records (185 males and 127 females) with the mean age of 27.6 showed that Odontogenic Keratocyst (OKC) was the most common odontogenic cyst of all followed by the dentigerous cyst as the second most common lesion. Most of the patients were in the second or third decades of their lives, although there was no statistically significant age distribution. The finding of the current study showed that calcifying odontogenic cyst (COC) occurrence was significantly related to the history of trauma. Enucleation and curettage of the odontogenic cysts were the most common treatment plans of all. The current study showed that clinicians should consider the many factors associated with the occurrence of odontogenic cysts.

Common variants on chromosome 6p22.1 are associated with schizophrenia

PubMed Central

Shi, Jianxin; Levinson, Douglas F.; Duan, Jubao; Sanders, Alan R.; Zheng, Yonglan; Pe'er, Itsik; Dudbridge, Frank; Holmans, Peter A.; Whittemore, Alice S.; Mowry, Bryan J.; Olincy, Ann; Amin, Farooq; Cloninger, C. Robert; Silverman, Jeremy M.; Buccola, Nancy G.; Byerley, William F.; Black, Donald W.; Crowe, Raymond R.; Oksenberg, Jorge R.; Mirel, Daniel B.; Kendler, Kenneth S.; Freedman, Robert; Gejman, Pablo V.

2009-01-01

Schizophrenia, a devastating psychiatric disorder, has a prevalence of 0.5–1%, with high heritability (80–85%) and complex transmission.1 Recent studies implicate rare, large, high-penetrance copy number variants (CNVs) in some cases2, but it is not known what genes or biological mechanisms underlie susceptibility. Here we show that schizophrenia is significantly associated with single nucleotide polymorphisms (SNPs) in the extended Major Histocompatibility Complex (MHC) region on chromosome 6. We carried out a genome-wide association study (GWAS) of common SNPs in the Molecular Genetics of Schizophrenia (MGS) case-control sample, and then a meta-analysis of data from the MGS, International Schizophrenia Consortium (ISC) and SGENE datasets. No MGS finding achieved genome-wide statistical significance. In the meta-analysis of European-ancestry subjects (8,008 cases, 19,077 controls), significant association with schizophrenia was observed in a region of linkage disequilibrium on chromosome 6p22.1 (P = 9.54 × 10−9). This region includes a histone gene cluster and several immunity-related genes, possibly implicating etiologic mechanisms involving chromatin modification, transcriptional regulation, auto-immunity and/or infection. These results demonstrate that common schizophrenia susceptibility alleles can be detected. The characterization of these signals will suggest important directions for research on susceptibility mechanisms. PMID:19571809

Antimicrobial properties of Cocos nucifera (coconut) husk: An extrapolation to oral health

PubMed Central

Jose, Maji; Cyriac, Maria B; Pai, Vidya; Varghese, Ipe; Shantaram, Manjula

2014-01-01

Background and Objectives: Brushing the teeth with fibrous husk of Cocos nucifera (coconut) is a common oral hygiene practice among people of rural areas of South India. However, the probable antimicrobial properties of this plant material against common oral pathogens have not been proved scientifically. Therefore, the present study was designed. Materials and Methods: Alcoholic extract of the husk of Cocos nucifera was prepared and the antimicrobial properties against common oral pathogens like cariogenic bacteria, periodontal pathogens, and candidal organisms were performed by the Agar Well Diffusion Method. The results obtained were then subjected to statistical analysis using One-Way Analysis of Variance (ANOVA) and the Tukey's Honestly Significant Difference (HSD). Results: The alcoholic extract of Cocos nucifera showed a significant concentration-dependent antimicrobial activity, expressed as a zone of inhibition with respect to all tested organisms except Actinomyces species. The inhibitory effect was more significant, with a majority of cariogenic organisms and Candida, with a zone of inhibition ranging from 4.6 mm to 16.3 mm. However, the effect was lesser with Cocos nucifera compared to chlorhexidine. Minimum inhibitory concentration (MIC) ranged from 50 mg/ml to 75 mg/ml. Conclusion: Cocos nucifera has a significant inhibitory action against common oral pathogens, indicating the presence of highly effective antimicrobial compounds. Therefore, it is proved that its use can contribute to oral health to a great extent. Identification of these active compounds provides the scope for incorporating it into a modern oral care system, so as to control oral diseases. PMID:25097415

Common injuries in athletes' knee: experience of a specialized center

PubMed Central

Nicolini, Alexandre Pedro; de Carvalho, Rogério Teixeira; Matsuda, Marcelo Mitsuro; Sayum, Jorge; Cohen, Moisés

2014-01-01

OBJECTIVE: The present cross-sectional study aims to identify the most common knee injuries in athletes cared at a Specialized Outpatient Clinics. METHOD: Analysis of patients cared at the Knee Outpatient Clinics of a Sports Trauma Center, divided by gender, age and diagnosed injury. RESULTS: Initially 440 patients were divided into 33 types of sports; after excluding the less statistically significant practices, nine sports remained. The most frequently performed sports were football with almost 50% of total patients presenting anterior cruciate ligament (ACL) injury, and road runs with great frequency of meniscal injury. There was no correlation of the disorder with the type of sports performed but a correlation was found with patient's age/gender. CONCLUSION: The complete ACL rupture was the most common injury found in football, basketball and volleyball players, followed by meniscal injury in street runners. Level of Evidence IV, Study Transversal. PMID:25061417

FDA Approval Summary: Temsirolimus as Treatment for Advanced Renal Cell Carcinoma

PubMed Central

Prowell, Tatiana M.; Ibrahim, Amna; Farrell, Ann T.; Justice, Robert; Mitchell, Shan Sun; Sridhara, Rajeshwari; Pazdur, Richard

2010-01-01

This report summarizes the U.S. Food and Drug Administration (FDA)'s approval of temsirolimus (Torisel®), on May 30, 2007, for the treatment of advanced renal cell carcinoma (RCC). Information provided includes regulatory history, study design, study results, and literature review. A multicenter, three-arm, randomized, open-label study was conducted in previously untreated patients with poor-prognosis, advanced RCC. The study objectives were to compare overall survival (OS), progression-free survival (PFS), objective response rate, and safety in patients receiving interferon (IFN)-α versus those receiving temsirolimus alone or in combination with IFN-α. In the second planned interim analysis of the intent-to-treat population (n = 626), there was a statistically significant longer OS time in the temsirolimus (25 mg) arm than in the IFN-α arm (median, 10.9 months versus 7.3 months; hazard ratio [HR], 0.73; p = .0078). The combination of temsirolimus (15 mg) and IFN-α did not lead to a significant difference in OS compared with IFN-α alone. There was also a statistically significant longer PFS time for the temsirolimus (25 mg) arm than for the IFN-α arm (median, 5.5 months versus 3.1 months; HR, 0.66, p = .0001). Common adverse reactions reported in patients receiving temsirolimus were rash, asthenia, and mucositis. Common laboratory abnormalities were anemia, hyperglycemia, hyperlipidemia, and hypertriglyceridemia. Serious but rare cases of interstitial lung disease, bowel perforation, and acute renal failure were observed. Temsirolimus has demonstrated superiority in terms of OS and PFS over IFN-α and provides an additional treatment option for patients with advanced RCC. PMID:20332142

The effect of lead poisoning on hematologic and biochemical values in trumpeter swans and Canada geese.

PubMed

Katavolos, P; Staempfli, S; Sears, W; Gancz, A Y; Smith, D A; Bienzle, D

2007-12-01

Lead is a persistent contaminant in the environment, and waterfowl are susceptible to lead toxicity from ingestion of lead pellets and fishing weights. Lead affects numerous physiologic processes through inhibition of enzyme activity and protein function, but its effects on commonly assessed avian blood values are incompletely understood. Our aim was to evaluate hematologic and biochemical changes associated with blood lead concentrations in trumpeter swans and Canada geese. Data for CBCs, plasma biochemical profiles (total protein, albumin, glucose, cholesterol, total bilirubin, calcium, phosphorus, gamma-glutamyltransferase [GGT], aspartate aminotransferase, lactate dehydrogenase, glutamate dehydrogenase, creatine kinase, amylase, and lipase), and whole blood lead concentrations were retrospectively analyzed for 69 trumpeter swans and 52 Canada geese. Laboratory data obtained prospectively from an additional 20 trumpeter swans also were included. RBC morphology was semiquantitated in blood smears from 70 of the birds. Data were analyzed initially by ANOVA and covariance. A statistical model then was constructed to determine the relationship between each parameter and lead concentration. In both avian species, PCV, hemoglobin concentration, and MCHC decreased significantly (P < .05) with increasing blood lead concentration. Uric acid concentration and GGT activity were increased in trumpeter swans and phosphorus concentration was decreased in Canada geese in association with high blood lead concentration (P < .05). Lead toxicosis induced significant changes in the values of commonly measured hematologic parameters in waterfowl. These changes may be useful indicators of severe lead intoxication during routine laboratory assessment. Changes in clinical chemistry values, although statistically significant, were too inconsistent to serve as indicators of lead toxicosis.

Skin hydration and transepidermal water loss in patients with a history of sulfur mustard contact: a case-control study.

PubMed

Davoudi, Seyyed Masoud; Keshavarz, Saeed; Sadr, Bardia; Shohrati, Majid; Naghizadeh, Mohammad Mehdi; Farsinejad, Khalil; Rashighi-Firouzabadi, Mehdi; Zartab, Hamed; Firooz, Alireza

2009-08-01

Skin lesions are among the most common complications of contact with sulfur mustard. This study was aimed to measure skin water content and transepidermal water loss (TEWL) in patients with a history of sulfur mustard contact. Three hundred ten male participants were included in this study: 87 (28.1%) sulfur mustard-exposed patients with current skin lesions (group 1), 71 (22.9%) sulfur mustard-exposed patients without skin lesions (group 2), 78 (25.2%) patients with dermatitis (group 3) and 74 (23.8%) normal controls (group 4) The water content and TEWL of skin was measured at four different locations of the body: forehead, suprasternal, palm and dorsum of hand. Nonparametric statistical tests (Kruskal-Wallis) were used to compare the four groups, and P < 0.05 was considered statistically significant. The mean age of participants were 44.0 +/- 6.7, 41.9 +/- 5.9, 43.8 +/- 9.3 and 44.8 +/- 8.9 years in groups 1 to 4, respectively (P = 0.146). Xerosis, post-lesional hyperpigmentation and lichenification were significantly more common in either sulfur mustard-exposed participants or non-exposed participants with dermatitis (P < 0.05). Skin hydration was higher in subjects with sulfur mustard contact than in non-injured participants (P < 0.05) in the dorsum and palm of hands and forehead. TEWL was significantly higher in participants only in suprasternal area and dorsum of hand. Contact with sulfur mustard agent can alter biophysical properties of the skin--especially the function of stratum corneum as a barrier to water loss-several years after exposure.

The Chondrogenic Induction Potential for Bone Marrow-Derived Stem Cells between Autologous Platelet-Rich Plasma and Common Chondrogenic Induction Agents: A Preliminary Comparative Study.

PubMed

Wang, Shan-Zheng; Chang, Qing; Kong, Xiang-Fei; Wang, Chen

2015-01-01

The interests in platelet-rich plasma (PRP) and their application in stem cell therapy have contributed to a better understanding of the basic biology of the prochondrogenesis effect on bone marrow-derived stem cells (BMSCs). We aimed at comparing the effect of autologous PRP with common chondrogenic induction agents (CCIAs) on the chondrogenic differentiation of BMSCs. Rabbit BMSCs were isolated and characterized by flow cytometry and differentiated towards adipocytes and osteoblasts. The chondrogenic response of BMSCs to autologous PRP and CCIAs which included transforming growth factor-β1 (TGF-β1), dexamethasone (DEX), and vitamin C (Vc) was examined by cell pellet culture. The isolated BMSCs after two passages highly expressed CD29 and CD44 but minimally expressed CD45. The osteogenic and adipogenic differentiation potentials of the isolated BMSCs were also confirmed. Compared with common CCIAs, autologous PRP significantly upregulated the chondrogenic related gene expression, including Col-2, AGC, and Sox-9. Osteogenic related gene expression, including Col-1 and OCN, was not of statistical significance between these two groups. Thus, our data shows that, compared with common chondrogenic induction agents, autologous PRP can be more effective in promoting the chondrogenesis of BMSCs.

Genes and (Common) Pathways Underlying Drug Addiction

PubMed Central

Li, Chuan-Yun; Mao, Xizeng; Wei, Liping

2008-01-01

Drug addiction is a serious worldwide problem with strong genetic and environmental influences. Different technologies have revealed a variety of genes and pathways underlying addiction; however, each individual technology can be biased and incomplete. We integrated 2,343 items of evidence from peer-reviewed publications between 1976 and 2006 linking genes and chromosome regions to addiction by single-gene strategies, microrray, proteomics, or genetic studies. We identified 1,500 human addiction-related genes and developed KARG (http://karg.cbi.pku.edu.cn), the first molecular database for addiction-related genes with extensive annotations and a friendly Web interface. We then performed a meta-analysis of 396 genes that were supported by two or more independent items of evidence to identify 18 molecular pathways that were statistically significantly enriched, covering both upstream signaling events and downstream effects. Five molecular pathways significantly enriched for all four different types of addictive drugs were identified as common pathways which may underlie shared rewarding and addictive actions, including two new ones, GnRH signaling pathway and gap junction. We connected the common pathways into a hypothetical common molecular network for addiction. We observed that fast and slow positive feedback loops were interlinked through CAMKII, which may provide clues to explain some of the irreversible features of addiction. PMID:18179280

Evidence-based treatments for low sexual desire in women.

PubMed

Brotto, Lori A

2017-04-01

Low sexual desire is the most common sexual complaint in women, with multinational studies finding that at least a third of women experience low sexual desire. No single etiology for the development of Female Sexual Interest/Arousal Disorder, the diagnosis laid out by the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders, has been established. There has been considerable interest in pharmacological approaches to improving low desire, and agents targeting a range of neurotransmitters have been examined. To date, only flibanserin, a centrally acting medication targeting the serotonin, dopamine, and norepinephrine systems, has been approved by the Food and Drug Administration (FDA). Despite statistically significant effects on sexual desire, sexual distress, and sexually satisfying events, side-effects are significant, and flibanserin is completely contraindicated with alcohol. As such, there has been renewed interest in advancing the science of psychological approaches to low desire, including cognitive behavioral and mindfulness therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

Biotherapeutic formulation factors affecting metal leachables from stainless steel studied by design of experiments.

PubMed

Zhou, Shuxia; Evans, Brad; Schöneich, Christian; Singh, Satish K

2012-03-01

Trace amounts of metals are inevitably present in biotherapeutic products. They can arise from various sources. The impact of common formulation factors such as protein concentration, antioxidant, metal chelator concentration and type, surfactant, pH, and contact time with stainless steel on metal leachables was investigated by a design of experiments approach. Three major metal leachables, iron, chromium, and nickel were monitored by inductively coupled plasma-mass spectrometry. It was observed that among all the tested factors, contact time, metal chelator concentration, and protein concentration were statistically significant factors with higher temperature resulting in higher levels of leached metals. Within a pH range of 5.5-6.5, solution pH played a minor role for chromium leaching at 25°C. No statistically significant difference was observed due to type of chelator, presence of antioxidant, or surfactant. In order to optimize a biotherapeutic formulation to achieve a target drug product shelf life with acceptable quality, each formulation component must be evaluated for its impact.

Acute myeloid leukemia risk by industry and occupation.

PubMed

Tsai, Rebecca J; Luckhaupt, Sara E; Schumacher, Pam; Cress, Rosemary D; Deapen, Dennis M; Calvert, Geoffrey M

2014-11-01

Acute myeloid leukemia (AML) is the most common type of leukemia found in adults. Identifying jobs that pose a risk for AML may be useful for identifying new risk factors. A matched case-control analysis was conducted using California Cancer Registry data from 1988 to 2007. This study included 8999 cases of AML and 24 822 controls. Industries with a statistically significant increased AML risk were construction (matched odds ratio [mOR] = 1.13); crop production (mOR = 1.41); support activities for agriculture and forestry (mOR = 2.05); and animal slaughtering and processing (mOR = 2.09). Among occupations with a statistically significant increased AML risk were miscellaneous agricultural workers (mOR = 1.76); fishers and related fishing workers (mOR = 2.02); nursing, psychiatric and home health aides (mOR = 1.65); and janitors and building cleaners (mOR = 1.54). Further investigation is needed to confirm study findings and to identify specific exposures responsible for the increased risks.

Measurement of air contamination in different wards of public sector hospital, Sukkur.

PubMed

Memon, Badaruddin AllahDino; Bhutto, Gul Hassan; Rizvi, Wajid Hussain

2016-11-01

The aim of this study was to evaluate and assess the index of bacterial contamination in different wards of the Public Sector Hospital of Sukkur (Teaching) Pakistan; whether or not the air contamination was statistically different from the acceptable level using active and passive sampling. In addition to this main hypothesis, other investigations included: occurrence of the most common bacteria, whether or not the bacterial contamination in the wards was a persistent problem and identification of the effective antibiotics against the indentified bacteria. The evidence sought based on the One Sample T test suggests that there is a (statistically) significant difference between the observed (higher) than the acceptance level (p<0.01), the result based on One-Way ANOVA suggests that the contamination problem was persistent as there was no significant difference among observed contamination of all three visits at (p>0.01) and the result of antibiotic susceptibility test highlights sensitivity and resistance level of antibiotics for the indentified bacteria.

Reliability of dietary information from surrogate respondents.

PubMed

Hislop, T G; Coldman, A J; Zheng, Y Y; Ng, V T; Labo, T

1992-01-01

A self-administered food frequency questionnaire was included as part of a case-control study of breast cancer in 1980-82. In 1986-87, a second food frequency questionnaire was sent to surviving cases and husbands of deceased cases; 30 spouses (86% response rate) and 263 surviving cases (88% response rate) returned questionnaires. The dietary questions concerned consumption of specific food items by the case before diagnosis of breast cancer. Missing values were less common in the second questionnaire; there was no significant difference in missing values between surviving cases and spouses of deceased cases. Kappa statistics comparing responses in the first and second questionnaires were significantly lower for spouses of deceased cases than for surviving cases. Reported level of confidence by the husbands regarding knowledge about their wives' eating habits did not influence the kappa statistics or the frequencies of missing values. The lack of good agreement has important implications for the use of proxy interviews from husbands in retrospective dietary studies.

Pelvic Floor Muscle Exercise for Paediatric Functional Constipation.

PubMed

Farahmand, Fatemeh; Abedi, Aidin; Esmaeili-Dooki, Mohammad Reza; Jalilian, Rozita; Tabari, Sanaz Mehrabani

2015-06-01

Functional constipation (FC) is one of the most common gastrointestinal problems among children. This study was designed to investigate the effectiveness of pelvic floor muscle exercise on treatment of FC. In this study which was conducted in Children's Medical Center, children with a diagnosis of FC (aged 4-18 y) who did not respond to medical treatment, performed sessions of pelvic floor muscle exercise at home twice a day for 8 wk. Frequency of defecation, overall improvement of constipation, stool withholding, painful defecation and stool consistency were measured at the final week of the intervention compared to baseline. Forty children (16 males, 24 females mean age 5.6±1.03 y) completed the 8-wk exercise program. Subjective overall improvement of the symptoms was present in 36 patients (90%). The changes in stool frequency, stool diameter and consistency were statistically significant. However, there were no statistically significant differences in the stool withholding, fecal impaction, fecal incontinence and painful defecation. Pelvic floor muscle exercise is an effective non-pharmacologic treatment for Paediatric FC.

Acute myeloid leukemia risk by industry and occupation

PubMed Central

Tsai, Rebecca J.; Luckhaupt, Sara E.; Schumacher, Pam; Cress, Rosemary D.; Deapen, Dennis M.; Calvert, Geoffrey M.

2015-01-01

Acute myeloid leukemia (AML) is the most common type of leukemia found in adults. Identifying jobs that pose a risk for AML may be useful for identifying new risk factors. A matched case–control analysis was conducted using California Cancer Registry data from 1988 to 2007. This study included 8999 cases of AML and 24 822 controls. Industries with a statistically significant increased AML risk were construction (matched odds ratio [mOR] = 1.13); crop production (mOR = 1.41); support activities for agriculture and forestry (mOR = 2.05); and animal slaughtering and processing (mOR = 2.09). Among occupations with a statistically significant increased AML risk were miscellaneous agricultural workers (mOR = 1.76); fishers and related fishing workers (mOR = 2.02); nursing, psychiatric and home health aides (mOR = 1.65); and janitors and building cleaners (mOR = 1.54). Further investigation is needed to confirm study findings and to identify specific exposures responsible for the increased risks. PMID:24547710

A visual basic program to generate sediment grain-size statistics and to extrapolate particle distributions

USGS Publications Warehouse

Poppe, L.J.; Eliason, A.H.; Hastings, M.E.

2004-01-01

Measures that describe and summarize sediment grain-size distributions are important to geologists because of the large amount of information contained in textural data sets. Statistical methods are usually employed to simplify the necessary comparisons among samples and quantify the observed differences. The two statistical methods most commonly used by sedimentologists to describe particle distributions are mathematical moments (Krumbein and Pettijohn, 1938) and inclusive graphics (Folk, 1974). The choice of which of these statistical measures to use is typically governed by the amount of data available (Royse, 1970). If the entire distribution is known, the method of moments may be used; if the next to last accumulated percent is greater than 95, inclusive graphics statistics can be generated. Unfortunately, earlier programs designed to describe sediment grain-size distributions statistically do not run in a Windows environment, do not allow extrapolation of the distribution's tails, or do not generate both moment and graphic statistics (Kane and Hubert, 1963; Collias et al., 1963; Schlee and Webster, 1967; Poppe et al., 2000)1.Owing to analytical limitations, electro-resistance multichannel particle-size analyzers, such as Coulter Counters, commonly truncate the tails of the fine-fraction part of grain-size distributions. These devices do not detect fine clay in the 0.6–0.1 μm range (part of the 11-phi and all of the 12-phi and 13-phi fractions). Although size analyses performed down to 0.6 μm microns are adequate for most freshwater and near shore marine sediments, samples from many deeper water marine environments (e.g. rise and abyssal plain) may contain significant material in the fine clay fraction, and these analyses benefit from extrapolation.The program (GSSTAT) described herein generates statistics to characterize sediment grain-size distributions and can extrapolate the fine-grained end of the particle distribution. It is written in Microsoft Visual Basic 6.0 and provides a window to facilitate program execution. The input for the sediment fractions is weight percentages in whole-phi notation (Krumbein, 1934; Inman, 1952), and the program permits the user to select output in either method of moments or inclusive graphics statistics (Fig. 1). Users select options primarily with mouse-click events, or through interactive dialogue boxes.

SEER Cancer Stat Facts

Cancer.gov

These summaries provide statistics for common cancer types. The statistics include incidence, mortality, survival, stage, prevalence, and lifetime risk. Links to additional resources are included. Updated annually.

Dental injuries in autistic patients.

PubMed

Altun, Ceyhan; Guven, Gunseli; Yorbik, Ozgur; Acikel, Cengizhan

2010-01-01

The purpose of this study was to assess the incidence of traumatic dental injury among Turkish children and young adults with autism and compare this to the general population of Turkish children and young adults without autism. This study was comprised of 186 children and young adults (138 males and 48 females), 93 with autism (autistic group, or AG) and 93 without autism (control group, or CG). Dental injuries were classified according to drawings and texts based on the WHO classification system, as modified by Andreasen and Andreasen. The rate of injury was higher among the AG (23%) than the CG (15%). The difference between the 2 groups, however, was not statistically significant (P<.19). The most common type of dental injury was enamel fracture. The rate of enamel fracture was higher in the CG (59%) than in the AG (33%), and the distribution of types of traumatic injury differed significantly between the AG and CG (P>.01). There were no significant differences in the rates of traumatic dental injuries among children and young adults with and without autistic disorder. The most frequently injured teeth were the permanent maxillary central incisors, and the frequency of injury to these teeth differed significantly (P>.01) between AG (56%) and CG (91%). The most common type of dental injury, enamel fracture, was more common in CG (59%) than AG (33%). The distribution of types of traumatic dental injuries differed significantly between the 2 groups (P>.01).

Analysis of spontaneous MEG activity in mild cognitive impairment and Alzheimer's disease using spectral entropies and statistical complexity measures

NASA Astrophysics Data System (ADS)

Bruña, Ricardo; Poza, Jesús; Gómez, Carlos; García, María; Fernández, Alberto; Hornero, Roberto

2012-06-01

Alzheimer's disease (AD) is the most common cause of dementia. Over the last few years, a considerable effort has been devoted to exploring new biomarkers. Nevertheless, a better understanding of brain dynamics is still required to optimize therapeutic strategies. In this regard, the characterization of mild cognitive impairment (MCI) is crucial, due to the high conversion rate from MCI to AD. However, only a few studies have focused on the analysis of magnetoencephalographic (MEG) rhythms to characterize AD and MCI. In this study, we assess the ability of several parameters derived from information theory to describe spontaneous MEG activity from 36 AD patients, 18 MCI subjects and 26 controls. Three entropies (Shannon, Tsallis and Rényi entropies), one disequilibrium measure (based on Euclidean distance ED) and three statistical complexities (based on Lopez Ruiz-Mancini-Calbet complexity LMC) were used to estimate the irregularity and statistical complexity of MEG activity. Statistically significant differences between AD patients and controls were obtained with all parameters (p < 0.01). In addition, statistically significant differences between MCI subjects and controls were achieved by ED and LMC (p < 0.05). In order to assess the diagnostic ability of the parameters, a linear discriminant analysis with a leave-one-out cross-validation procedure was applied. The accuracies reached 83.9% and 65.9% to discriminate AD and MCI subjects from controls, respectively. Our findings suggest that MCI subjects exhibit an intermediate pattern of abnormalities between normal aging and AD. Furthermore, the proposed parameters provide a new description of brain dynamics in AD and MCI.

Common pitfalls in statistical analysis: Absolute risk reduction, relative risk reduction, and number needed to treat

PubMed Central

Ranganathan, Priya; Pramesh, C. S.; Aggarwal, Rakesh

2016-01-01

In the previous article in this series on common pitfalls in statistical analysis, we looked at the difference between risk and odds. Risk, which refers to the probability of occurrence of an event or outcome, can be defined in absolute or relative terms. Understanding what these measures represent is essential for the accurate interpretation of study results. PMID:26952180

THE RADIO/GAMMA-RAY CONNECTION IN ACTIVE GALACTIC NUCLEI IN THE ERA OF THE FERMI LARGE AREA TELESCOPE

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

Ackermann, M.; Ajello, M.; Allafort, A.

We present a detailed statistical analysis of the correlation between radio and gamma-ray emission of the active galactic nuclei (AGNs) detected by Fermi during its first year of operation, with the largest data sets ever used for this purpose. We use both archival interferometric 8.4 GHz data (from the Very Large Array and ATCA, for the full sample of 599 sources) and concurrent single-dish 15 GHz measurements from the Owens Valley Radio Observatory (OVRO, for a sub sample of 199 objects). Our unprecedentedly large sample permits us to assess with high accuracy the statistical significance of the correlation, using amore » surrogate data method designed to simultaneously account for common-distance bias and the effect of a limited dynamical range in the observed quantities. We find that the statistical significance of a positive correlation between the centimeter radio and the broadband (E > 100 MeV) gamma-ray energy flux is very high for the whole AGN sample, with a probability of <10{sup -7} for the correlation appearing by chance. Using the OVRO data, we find that concurrent data improve the significance of the correlation from 1.6 x 10{sup -6} to 9.0 x 10{sup -8}. Our large sample size allows us to study the dependence of correlation strength and significance on specific source types and gamma-ray energy band. We find that the correlation is very significant (chance probability < 10{sup -7}) for both flat spectrum radio quasars and BL Lac objects separately; a dependence of the correlation strength on the considered gamma-ray energy band is also present, but additional data will be necessary to constrain its significance.« less

The radio/gamma-ray connection in active galactic nuclei in the era of the Fermi Large Area Telescope

DOE PAGES

Ackermann, M.; Ajello, M.; Allafort, A.; ...

2011-10-12

We present a detailed statistical analysis of the correlation between radio and gamma-ray emission of the active galactic nuclei (AGNs) detected by Fermi during its first year of operation, with the largest data sets ever used for this purpose. We use both archival interferometric 8.4 GHz data (from the Very Large Array and ATCA, for the full sample of 599 sources) and concurrent single-dish 15 GHz measurements from the Owens Valley Radio Observatory (OVRO, for a sub sample of 199 objects). Our unprecedentedly large sample permits us to assess with high accuracy the statistical significance of the correlation, using amore » surrogate data method designed to simultaneously account for common-distance bias and the effect of a limited dynamical range in the observed quantities. We find that the statistical significance of a positive correlation between the centimeter radio and the broadband (E > 100 MeV) gamma-ray energy flux is very high for the whole AGN sample, with a probability of <10 –7 for the correlation appearing by chance. Using the OVRO data, we find that concurrent data improve the significance of the correlation from 1.6 × 10 –6 to 9.0 × 10 –8. Our large sample size allows us to study the dependence of correlation strength and significance on specific source types and gamma-ray energy band. As a result, we find that the correlation is very significant (chance probability < 10 –7) for both flat spectrum radio quasars and BL Lac objects separately; a dependence of the correlation strength on the considered gamma-ray energy band is also present, but additional data will be necessary to constrain its significance.« less

The Radio/Gamma-Ray Connection in Active Galactic Nuclei in the Era of the Fermi Large Area Telescope

NASA Technical Reports Server (NTRS)

Ackermann, M.; Ajello, M.; Allafort, A.; Angelakis, E.; Axelsson, M.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.;

Clinicopathological significance of c-MYC in esophageal squamous cell carcinoma.

PubMed

Lian, Yu; Niu, Xiangdong; Cai, Hui; Yang, Xiaojun; Ma, Haizhong; Ma, Shixun; Zhang, Yupeng; Chen, Yifeng

2017-07-01

Esophageal squamous cell carcinoma is one of the most common malignant tumors. The oncogene c-MYC is thought to be important in the initiation, promotion, and therapy resistance of cancer. In this study, we aim to investigate the clinicopathologic roles of c-MYC in esophageal squamous cell carcinoma tissue. This study is aimed at discovering and analyzing c-MYC expression in a series of human esophageal tissues. A total of 95 esophageal squamous cell carcinoma samples were analyzed by the western blotting and immunohistochemistry techniques. Then, correlation of c-MYC expression with clinicopathological features of esophageal squamous cell carcinoma patients was statistically analyzed. In most esophageal squamous cell carcinoma cases, the c-MYC expression was positive in tumor tissues. The positive rate of c-MYC expression in tumor tissues was 61.05%, obviously higher than the adjacent normal tissues (8.42%, 8/92) and atypical hyperplasia tissues (19.75%, 16/95). There was a statistical difference among adjacent normal tissues, atypical hyperplasia tissues, and tumor tissues. Overexpression of the c-MYC was detected in 61.05% (58/95) esophageal squamous cell carcinomas, which was significantly correlated with the degree of differentiation (p = 0.004). The positive rate of c-MYC expression was 40.0% in well-differentiated esophageal tissues, with a significantly statistical difference (p = 0.004). The positive rate of c-MYC was 41.5% in T1 + T2 esophageal tissues and 74.1% in T3 + T4 esophageal tissues, with a significantly statistical difference (p = 0.001). The positive rate of c-MYC was 45.0% in I + II esophageal tissues and 72.2% in III + IV esophageal tissues, with a significantly statistical difference (p = 0.011). The c-MYC expression strongly correlated with clinical staging (p = 0.011), differentiation degree (p = 0.004), lymph node metastasis (p = 0.003), and invasion depth (p = 0.001) of patients with esophageal squamous cell carcinoma. The c-MYC was differentially expressed in a series of human esophageal tissues, and the aberrant c-MYC expression could be a potential factor in carcinogenesis and progression of esophageal squamous cell carcinoma. There was a statistical signification for c-MYC in esophageal squamous cell carcinoma patients to analyze clinicopathological features. It possibly becomes a new diagnostic indicator of esophageal squamous cell carcinoma.

Fabricating data: How substituting values for nondetects can ruin results, and what can be done about it

USGS Publications Warehouse

Helsel, D.R.

2006-01-01

The most commonly used method in environmental chemistry to deal with values below detection limits is to substitute a fraction of the detection limit for each nondetect. Two decades of research has shown that this fabrication of values produces poor estimates of statistics, and commonly obscures patterns and trends in the data. Papers using substitution may conclude that significant differences, correlations, and regression relationships do not exist, when in fact they do. The reverse may also be true. Fortunately, good alternative methods for dealing with nondetects already exist, and are summarized here with references to original sources. Substituting values for nondetects should be used rarely, and should generally be considered unacceptable in scientific research. There are better ways.

Mobbing Exposure of Anaesthesiology Residents in Turkey

PubMed Central

Aykut, Gülnihal; Efe, Esra Mercanoğlu; Bayraktar, Selcan; Şentürk, Sinem; Başeğmez, İrem; Özkumit, Özlem; Kabak, Elmas; Yavaşçaoğlu, Belgin; Bilgin, Hülya

2016-01-01

Objective In recent years, psychological problems that are caused by working conditions, like burn out syndrome, are more commonly observed. In our study, we aimed to evaluate mobbing exposure, factors causing mobbing and precautions for mobbing in residency students who are educated in anaesthesiology and reanimation clinics in Turkey. Methods After obtaining consent from the ethics committee, we sent our questionnaires to the secretariats of the departments by postal mail. Completed questionnaires were collected in our department’s secretariat blindly and randomly mixed. One hundred and one participants were returned the questionnaires. Data was statistically analysed in SPSS 21.0 software programme. Results During residency programme, sated to have experienced mobbing one or more time. Interestingly, 5.9% participants complained of physical mobbing. Mobbing exposure was more common in females. The most serious new onset psychosomatic symptoms stated during residency were committing suicide (2%), addiction (16%), severe depression (18%), panic attack (8%), more accidents (7%) and tendency of violence (15%). In mobbing group there was statistically significant dissatisfaction rate. Conclusion In professions where mobbing is common, incidences of psychiatric diseases and suicide attempts are high are increased. Who are under risk for experiencing mobbing should be noticed carefully to ensure good judgement and problems should be inspected objectively in a detailed manner. Anesthesiology societies and other medical professional societies should establish mobbing committees. Thus, mobbing problems can be resolved and healthy career oppurtunities can be presented to residents. PMID:27909591

Mobbing Exposure of Anaesthesiology Residents in Turkey.

PubMed

Aykut, Gülnihal; Efe, Esra Mercanoğlu; Bayraktar, Selcan; Şentürk, Sinem; Başeğmez, İrem; Özkumit, Özlem; Kabak, Elmas; Yavaşçaoğlu, Belgin; Bilgin, Hülya

2016-08-01

In recent years, psychological problems that are caused by working conditions, like burn out syndrome, are more commonly observed. In our study, we aimed to evaluate mobbing exposure, factors causing mobbing and precautions for mobbing in residency students who are educated in anaesthesiology and reanimation clinics in Turkey. After obtaining consent from the ethics committee, we sent our questionnaires to the secretariats of the departments by postal mail. Completed questionnaires were collected in our department's secretariat blindly and randomly mixed. One hundred and one participants were returned the questionnaires. Data was statistically analysed in SPSS 21.0 software programme. During residency programme, sated to have experienced mobbing one or more time. Interestingly, 5.9% participants complained of physical mobbing. Mobbing exposure was more common in females. The most serious new onset psychosomatic symptoms stated during residency were committing suicide (2%), addiction (16%), severe depression (18%), panic attack (8%), more accidents (7%) and tendency of violence (15%). In mobbing group there was statistically significant dissatisfaction rate. In professions where mobbing is common, incidences of psychiatric diseases and suicide attempts are high are increased. Who are under risk for experiencing mobbing should be noticed carefully to ensure good judgement and problems should be inspected objectively in a detailed manner. Anesthesiology societies and other medical professional societies should establish mobbing committees. Thus, mobbing problems can be resolved and healthy career oppurtunities can be presented to residents.

Webuye Health and Demographic Surveillance Systems Baseline Survey of Soil-Transmitted Helminths and Intestinal Protozoa among Children up to Five Years

PubMed Central

Obala, A. A.; Simiyu, C. J.; Odhiambo, D. O.; Nanyu, V.; Chege, P.; Downing, R.; Mwaliko, E.; Mwangi, A. W.; Menya, D.; Chelagat, D.; Nyamogoba, H. D. N.; Ayuo, P. O.; O'Meara, W. P.; Twagirumukiza, M.; Vandenbroek, D.; Otsyula, B. B. O.; de Maeseneer, J.

2013-01-01

Background. The intestinal parasitic infections (IPIs) are globally endemic, and they constitute the greatest cause of illness and disease worldwide. Transmission of IPIs occurs as a result of inadequate sanitation, inaccessibility to potable water, and poor living conditions. Objectives. To determine a baseline prevalence of IPIs among children of five years and below at Webuye Health and Demographic Surveillance (HDSS) area in western Kenya. Methods. Cross-sectional survey was used to collect data. Direct saline and formal-ether-sedimentation techniques were used to process the specimens. Descriptive and inferential statistics such as Chi-square statistics were used to analyze the data. Results. A prevalence of 52.3% (417/797) was obtained with the male child slightly more infected than the female (53.5% versus 51%), but this was not significant (χ 2 = 0.482, P > 0.05). Giardia lamblia and Entamoeba histolytica were the most common pathogenic IPIs with a prevalence of 26.1% (208/797) and 11.2% (89/797), respectively. Soil-transmitted helminths (STHs) were less common with a prevalence of 4.8% (38/797), 3.8% (30/797), and 0.13% (1/797) for Ascaris lumbricoides, hookworms, and Trichuris trichiura, respectively. Conclusions. Giardia lamblia and E. histolytica were the most prevalent pathogenic intestinal protozoa, while STHs were less common. Community-based health promotion techniques are recommended for controlling these parasites. PMID:23533444

Subacromial injection of autologous platelet-rich plasma versus corticosteroid for the treatment of symptomatic partial rotator cuff tears.

PubMed

Shams, Ahmed; El-Sayed, Mohamed; Gamal, Osama; Ewes, Waled

2016-12-01

Rotator cuff tears are one of the most common causes of chronic shoulder pain and disability. They significantly affect the quality of life. Reduced pain and improved function are the goals of conventional therapy, which includes relative rest, pain therapy, physical therapy, corticosteroid injections and surgical intervention. Tendons have a relative avascular nature; hence, their regenerative potential is limited. There is some clinical evidence that the application of autologous platelets may help to revascularize the area of injury in rotator cuff pathologies. This prospective randomized controlled study was done to evaluate the results of subacromial injection of platelet-rich plasma (PRP) versus corticosteroid injection therapy in 40 patients with symptomatic partial rotator cuff tears. All patients were assessed before injection, 6 weeks, 3 and 6 months after injection, using the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), the Constant-Murley Score (CMS), the Simple Shoulder Test (SST) and a Visual Analog Scale (VAS) for pain. An MRI was performed before and 6 months after the injection for all the included patients and was graded on 0-5 scale. Both injection groups showed statistically significantly better clinical outcomes over time compared with those before injection. There was a statistically significant difference between RPP group and corticosteroid group 12 weeks after injection, regarding VAS, ASES, CMS and SST in favor of the RPP group. MRI showed an overall slight nonsignificant improvement in grades of tendinopathy/tear in both groups, however, without statistically significant differences between the two groups. PRP injections showed earlier better results as compared to corticosteroid injections, although statistically significant better results after 6 months could not be found. Therefore, subacromial RPP injection could be considered as a good alternative to corticosteroid injection, especially in patients with a contraindication to corticosteroid administration. II.

Clinicodemographic Profile of Children with Seizures in a Tertiary Care Hospital: A Cross-Sectional Observational Study.

PubMed

Chaudhary, Nagendra; Gupta, Murli Manohar; Shrestha, Sandeep; Pathak, Santosh; Kurmi, Om Prakash; Bhatia, B D; Agarwal, K N

2017-01-01

Seizures are one of the common causes for hospital admissions in children with significant mortality and morbidity. This study was conducted to study the prevalence and clinicodemographic profile of children with seizures in a tertiary care hospital of western Nepal. This prospective cross-sectional study conducted over a period of 2 years included all admitted children (2 months-16 years) with seizures. Among 4962 admitted children, seizures were present in 3.4% ( n = 168) of children, with male preponderance. 138 (82.1%) children had generalized tonic-clonic seizures (GTCS) and 30 (17.9%) children had partial seizures. GTCS were more common than partial seizures in both sexes (male = 82.7%; female = 81.2%) and age groups. There was no statistical significance in the distribution of seizures (GTCS and partial seizures) with sexes ( P = 0.813) and age groups ( P = 0.955). Mean ages of children having GTCS and partial seizures were 8.2 ± 4.6 years and 8.2 ± 4.2 years, respectively. Loss of consciousness (55.4%), fever (39.9%), vomiting (35.1%), and headache (16.1%) were common complaints in seizure patients. Significant number of GTCS cases had fever ( P = 0.041) and neurocysticercosis ( n = 72; 43%) was the most common etiology in seizure patients. Idiopathic epilepsy (38 (22.6%)), meningoencephalitis (26 (15.5%)), and febrile convulsions (14 (8.33%)) were other leading disorders in children with seizures.

Investigating Mathematics Teachers' Thoughts of Statistical Inference

ERIC Educational Resources Information Center

Yang, Kai-Lin

2012-01-01

Research on statistical cognition and application suggests that statistical inference concepts are commonly misunderstood by students and even misinterpreted by researchers. Although some research has been done on students' misunderstanding or misconceptions of confidence intervals (CIs), few studies explore either students' or mathematics…

Innovations in curriculum design: A multi-disciplinary approach to teaching statistics to undergraduate medical students

PubMed Central

Freeman, Jenny V; Collier, Steve; Staniforth, David; Smith, Kevin J

2008-01-01

Background Statistics is relevant to students and practitioners in medicine and health sciences and is increasingly taught as part of the medical curriculum. However, it is common for students to dislike and under-perform in statistics. We sought to address these issues by redesigning the way that statistics is taught. Methods The project brought together a statistician, clinician and educational experts to re-conceptualize the syllabus, and focused on developing different methods of delivery. New teaching materials, including videos, animations and contextualized workbooks were designed and produced, placing greater emphasis on applying statistics and interpreting data. Results Two cohorts of students were evaluated, one with old style and one with new style teaching. Both were similar with respect to age, gender and previous level of statistics. Students who were taught using the new approach could better define the key concepts of p-value and confidence interval (p < 0.001 for both). They were more likely to regard statistics as integral to medical practice (p = 0.03), and to expect to use it in their medical career (p = 0.003). There was no significant difference in the numbers who thought that statistics was essential to understand the literature (p = 0.28) and those who felt comfortable with the basics of statistics (p = 0.06). More than half the students in both cohorts felt that they were comfortable with the basics of medical statistics. Conclusion Using a variety of media, and placing emphasis on interpretation can help make teaching, learning and understanding of statistics more people-centred and relevant, resulting in better outcomes for students. PMID:18452599

Mixed-strain housing for female C57BL/6, DBA/2, and BALB/c mice: validating a split-plot design that promotes refinement and reduction.

PubMed

Walker, Michael; Fureix, Carole; Palme, Rupert; Newman, Jonathan A; Ahloy Dallaire, Jamie; Mason, Georgia

2016-01-27

Inefficient experimental designs are common in animal-based biomedical research, wasting resources and potentially leading to unreplicable results. Here we illustrate the intrinsic statistical power of split-plot designs, wherein three or more sub-units (e.g. individual subjects) differing in a variable of interest (e.g. genotype) share an experimental unit (e.g. a cage or litter) to which a treatment is applied (e.g. a drug, diet, or cage manipulation). We also empirically validate one example of such a design, mixing different mouse strains -- C57BL/6, DBA/2, and BALB/c -- within cages varying in degree of enrichment. As well as boosting statistical power, no other manipulations are needed for individual identification if co-housed strains are differentially pigmented, so also sparing mice from stressful marking procedures. The validation involved housing 240 females from weaning to 5 months of age in single- or mixed- strain trios, in cages allocated to enriched or standard treatments. Mice were screened for a range of 26 commonly-measured behavioural, physiological and haematological variables. Living in mixed-strain trios did not compromise mouse welfare (assessed via corticosterone metabolite output, stereotypic behaviour, signs of aggression, and other variables). It also did not alter the direction or magnitude of any strain- or enrichment-typical difference across the 26 measured variables, or increase variance in the data: indeed variance was significantly decreased by mixed- strain housing. Furthermore, using Monte Carlo simulations to quantify the statistical power benefits of this approach over a conventional design demonstrated that for our effect sizes, the split- plot design would require significantly fewer mice (under half in most cases) to achieve a power of 80%. Mixed-strain housing allows several strains to be tested at once, and potentially refines traditional marking practices for research mice. Furthermore, it dramatically illustrates the enhanced statistical power of split-plot designs, allowing many fewer animals to be used. More powerful designs can also increase the chances of replicable findings, and increase the ability of small-scale studies to yield significant results. Using mixed-strain housing for female C57BL/6, DBA/2 and BALB/c mice is therefore an effective, efficient way to promote both refinement and the reduction of animal-use in research.

Comparative trial of sclerotherapy for hydroceles.

PubMed

Rencken, R K; Bornman, M S; Reif, S; Olivier, I

1990-04-01

We present a prospective single-blind trial of sclerotherapy for hydroceles with tetradecyl sulphate and rolitetracycline as sclerosants. Twenty-seven hydroceles were treated with tetradecyl sulphate and 28 with rolitetracycline. The median follow-up was 13 months. There were no statistically significant differences between the 2 drugs in respect of cure rate and complications. The overall cure rate for both drugs was 96%. Complications were rare and common to both drugs. Tetradecyl sulphate and rolitetracycline were found to be equally effective as sclerosants.

Treatment of hydrocele: randomised prospective study of simple aspiration and sclerotherapy with tetracycline.

PubMed

Breda, G; Giunta, A; Gherardi, L; Xausa, D; Silvestre, P; Tamai, A

1992-07-01

Following reports in the literature on the efficacy of tetracycline sclerotherapy in the treatment of hydroceles, we carried out a randomised prospective study of 45 patients (50 hydroceles), comparing simple evacuation with tetracycline sclerotherapy. The results revealed no statistically significant difference in the percentage of success between the 2 groups, but complications were more common in the patients treated with tetracycline. The good results reported by other authors in non-randomised studies are, therefore, not confirmed.

Relationships of concentrations of certain blood constituents with milk yield and age of cows in dairy herds.

PubMed

Kitchenham, B A; Rowlands, G J; Shorbagi, H

1975-05-01

Regression analyses were performed on data from 48 Compton metabolic profile tests relating the concentrations of certain constituents in the blood of dairy cows to their milk yield, age and stage of lactation. The common partial regression coefficients for milk yield, age and stage of lactation were estimated for each blood constituent. The relationships of greatest statistical significance were between the concentrations of inorganic phosphate and globulin and age, and the concentration of albumin and milk yield.

Screening for prostate cancer

NASA Technical Reports Server (NTRS)

Weirich, Stephen A.

1993-01-01

Despite recent advances in both the survival and cure rates for many forms of cancer, unfortunately the same has not been true for prostate cancer. In fact, the age-adjusted death rate from prostate cancer has not significantly improved since 1949, and prostate cancer remains the most common cancer in American men, causing the second highest cancer mortality rate. Topics discussed include the following: serum testosterone levels; diagnosis; mortality statistics; prostate-sppecific antigen (PSA) tests; and the Occupational Medicine Services policy at LeRC.

Autonomy and job satisfaction for a sample of Greek teachers.

PubMed

Koustelios, Athanasios D; Karabatzaki, Despina; Kousteliou, Ioanna

2004-12-01

Analysing the relation between Job Satisfaction and Autonomy in a sample of 300 Greek teachers (114 men and 186 women, 28 to 59 years old) from primary and secondary schools, showed statistically significant positive correlations between Job Satisfaction and Autonomy. Particularly, Autonomy was correlated with Job Itself (.21), Supervision (.22), and the Organizational as a Whole (.27), aspects of Job Satisfaction. Findings are in line with previous studies conducted in different cultural contexts. Percent common variance accounted for is small.

Conditions, interventions, and outcomes in nursing research: a comparative analysis of North American and European/International journals. (1981-1990).

PubMed

Abraham, I L; Chalifoux, Z L; Evers, G C; De Geest, S

1995-04-01

This study compared the conceptual foci and methodological characteristics of research projects which tested the effects of nursing interventions, published in four general nursing research journals with predominantly North American, and two with predominantly European/International authorship and readership. Dimensions and variables of comparison included: nature of subjects, design issues, statistical methodology, statistical power, and types of interventions and outcomes. Although some differences emerged, the most striking and consistent finding was that there were no statistically significant differences (and thus similarities) in the content foci and methodological parameters of the intervention studies published in both groups of journals. We conclude that European/International and North American nursing intervention studies, as reported in major general nursing research journals, are highly similar in the parameters studied, yet in need of overall improvement. Certainly, there is no empirical support for the common (explicit or implicit) ethnocentric American bias that leadership in nursing intervention research resides with and in the United States of America.

Statistical Method to Overcome Overfitting Issue in Rational Function Models

NASA Astrophysics Data System (ADS)

Alizadeh Moghaddam, S. H.; Mokhtarzade, M.; Alizadeh Naeini, A.; Alizadeh Moghaddam, S. A.

2017-09-01

Rational function models (RFMs) are known as one of the most appealing models which are extensively applied in geometric correction of satellite images and map production. Overfitting is a common issue, in the case of terrain dependent RFMs, that degrades the accuracy of RFMs-derived geospatial products. This issue, resulting from the high number of RFMs' parameters, leads to ill-posedness of the RFMs. To tackle this problem, in this study, a fast and robust statistical approach is proposed and compared to Tikhonov regularization (TR) method, as a frequently-used solution to RFMs' overfitting. In the proposed method, a statistical test, namely, significance test is applied to search for the RFMs' parameters that are resistant against overfitting issue. The performance of the proposed method was evaluated for two real data sets of Cartosat-1 satellite images. The obtained results demonstrate the efficiency of the proposed method in term of the achievable level of accuracy. This technique, indeed, shows an improvement of 50-80% over the TR.

Statistical analysis and interpretation of prenatal diagnostic imaging studies, Part 2: descriptive and inferential statistical methods.

PubMed

Tuuli, Methodius G; Odibo, Anthony O

2011-08-01

The objective of this article is to discuss the rationale for common statistical tests used for the analysis and interpretation of prenatal diagnostic imaging studies. Examples from the literature are used to illustrate descriptive and inferential statistics. The uses and limitations of linear and logistic regression analyses are discussed in detail.

Prediction of breast cancer risk by genetic risk factors, overall and by hormone receptor status.

PubMed

Hüsing, Anika; Canzian, Federico; Beckmann, Lars; Garcia-Closas, Montserrat; Diver, W Ryan; Thun, Michael J; Berg, Christine D; Hoover, Robert N; Ziegler, Regina G; Figueroa, Jonine D; Isaacs, Claudine; Olsen, Anja; Viallon, Vivian; Boeing, Heiner; Masala, Giovanna; Trichopoulos, Dimitrios; Peeters, Petra H M; Lund, Eiliv; Ardanaz, Eva; Khaw, Kay-Tee; Lenner, Per; Kolonel, Laurence N; Stram, Daniel O; Le Marchand, Loïc; McCarty, Catherine A; Buring, Julie E; Lee, I-Min; Zhang, Shumin; Lindström, Sara; Hankinson, Susan E; Riboli, Elio; Hunter, David J; Henderson, Brian E; Chanock, Stephen J; Haiman, Christopher A; Kraft, Peter; Kaaks, Rudolf

2012-09-01

There is increasing interest in adding common genetic variants identified through genome wide association studies (GWAS) to breast cancer risk prediction models. First results from such models showed modest benefits in terms of risk discrimination. Heterogeneity of breast cancer as defined by hormone-receptor status has not been considered in this context. In this study we investigated the predictive capacity of 32 GWAS-detected common variants for breast cancer risk, alone and in combination with classical risk factors, and for tumours with different hormone receptor status. Within the Breast and Prostate Cancer Cohort Consortium, we analysed 6009 invasive breast cancer cases and 7827 matched controls of European ancestry, with data on classical breast cancer risk factors and 32 common gene variants identified through GWAS. Discriminatory ability with respect to breast cancer of specific hormone receptor-status was assessed with the age adjusted and cohort-adjusted concordance statistic (AUROC(a)). Absolute risk scores were calculated with external reference data. Integrated discrimination improvement was used to measure improvements in risk prediction. We found a small but steady increase in discriminatory ability with increasing numbers of genetic variants included in the model (difference in AUROC(a) going from 2.7% to 4%). Discriminatory ability for all models varied strongly by hormone receptor status. Adding information on common polymorphisms provides small but statistically significant improvements in the quality of breast cancer risk prediction models. We consistently observed better performance for receptor-positive cases, but the gain in discriminatory quality is not sufficient for clinical application.

Depression among HIV/AIDS Sudanese patients: a cross-sectional analytic study.

PubMed

Elbadawi, Abdulateef; Mirghani, Hyder

2017-01-01

Depression and HIV/AIDS are common morbid health problems; the relationship is bidirectional exacerbating each other with deleterious consequences. There are limited studies on this topic in Sudan. In this study, we investigated depression among HIV/AIDS in Sudan. A cross-sectional analytic study was conducted among 362 HIV/AIDS patients from three centers in Khartoum, Sudan. Data were collected by the Hospital Depression and Anxiety (HADS) questionnaire. Chi-square was used for testing the significance and a P. Value of ≥ 0.05 was considered as statistically significant. Depression was evident in 332 (63.1%) of patients 68 (19.3%) had mild depression, 114 (32.4%) moderate depression, and 40 (11.4%) severe depression. Depression was commoner among women, illiterate, married/widowed, not receiving counseling, delaying the result of the test, P-value <0.05, no significant differences were found regarding test and treatment type P- Value >0.05. Depression was prevalent among HIV/AIDS patients, especially females, low level of education, and widowed/married patients, and those not receiving counseling and post diagnosis sessions.

Educational quality and the crisis of educational research

NASA Astrophysics Data System (ADS)

Heyneman, Stephen

1993-11-01

This paper was designed not as a research product but as a speech to comparative education colleagues. It argues that there is a crisis of educational quality in many parts of the world, and that there is a parallel crisis in the quality of educational research and statistics. Compared to other major public responsibilities in health, agriculture, population and family planning, educational statistics are poor and often getting worse. Our international and national statistical institutions are impoverished, and we as a profession have been part of the problem. We have been so busy arguing over differing research paradigms that we have not paid sufficient attention to our common professional responsibilities and common professional goals. The paper suggests that we, as professionals interested in comparative education issues, begin to act together more on these common and important issues.

A Statistical Test for Comparing Nonnested Covariance Structure Models.

ERIC Educational Resources Information Center

Levy, Roy; Hancock, Gregory R.

While statistical procedures are well known for comparing hierarchically related (nested) covariance structure models, statistical tests for comparing nonhierarchically related (nonnested) models have proven more elusive. While isolated attempts have been made, none exists within the commonly used maximum likelihood estimation framework, thereby…

Effect of clozapine and molindone on plasma and brain levels of mescaline in mice.

PubMed

Shah, N S; Gulati, O D

1984-01-01

Levels of unchanged mescaline were examined in the plasma and brain of albino Swiss-Webster mice pretreated with various doses of either clozapine or molindone. In clozapine treated mice, the mescaline levels were statistically significantly higher at 2 and 3 h with 7.5 and 15.0 mg/kg and at 1, 2 and 3 h with 30 mg/kg. Molindone at 4.0 and 8.0 mg/kg produced no significant effect; at 16.0 and 48.0 mg/kg, the levels were significantly higher at 1 and 2 h. Elevated brain levels of mescaline by clozapine and molindone indicate an adverse metabolic interaction between a hallucinogen and drugs that are commonly used to treat mescaline-induced psychosis.

Determination of the ascorbic acid content of two medicinal plants in Nigeria.

PubMed

H A, Okeri; P O, Alonge

2006-01-01

The fresh and dried leaves of two edible plants, Oldenlandia corymbosa and Dissotis rotundifolia have been assayed for their ascorbic acid content. They were found to be rich sources of ascorbic acid (vitamin C) when compared with some common garden fruits and vegetables. Students' t-test statistical analysis using INSTAT.EXE program for the results (mean+/-SEM) shows that there was no significant difference for the fresh leaves of the individual plants and also there is no significant difference for the dried leaves (P=0.05). However, there was significant difference between ascorbic acid content of the fresh and dried leaves of the same plant, obviously indicating that the fresh leaves contain more ascorbic acid than the dried leaves.

Analyzing longitudinal data with the linear mixed models procedure in SPSS.

PubMed

West, Brady T

2009-09-01

Many applied researchers analyzing longitudinal data share a common misconception: that specialized statistical software is necessary to fit hierarchical linear models (also known as linear mixed models [LMMs], or multilevel models) to longitudinal data sets. Although several specialized statistical software programs of high quality are available that allow researchers to fit these models to longitudinal data sets (e.g., HLM), rapid advances in general purpose statistical software packages have recently enabled analysts to fit these same models when using preferred packages that also enable other more common analyses. One of these general purpose statistical packages is SPSS, which includes a very flexible and powerful procedure for fitting LMMs to longitudinal data sets with continuous outcomes. This article aims to present readers with a practical discussion of how to analyze longitudinal data using the LMMs procedure in the SPSS statistical software package.

A systematic review of the quality of statistical methods employed for analysing quality of life data in cancer randomised controlled trials.

PubMed

Hamel, Jean-Francois; Saulnier, Patrick; Pe, Madeline; Zikos, Efstathios; Musoro, Jammbe; Coens, Corneel; Bottomley, Andrew

2017-09-01

Over the last decades, Health-related Quality of Life (HRQoL) end-points have become an important outcome of the randomised controlled trials (RCTs). HRQoL methodology in RCTs has improved following international consensus recommendations. However, no international recommendations exist concerning the statistical analysis of such data. The aim of our study was to identify and characterise the quality of the statistical methods commonly used for analysing HRQoL data in cancer RCTs. Building on our recently published systematic review, we analysed a total of 33 published RCTs studying the HRQoL methods reported in RCTs since 1991. We focussed on the ability of the methods to deal with the three major problems commonly encountered when analysing HRQoL data: their multidimensional and longitudinal structure and the commonly high rate of missing data. All studies reported HRQoL being assessed repeatedly over time for a period ranging from 2 to 36 months. Missing data were common, with compliance rates ranging from 45% to 90%. From the 33 studies considered, 12 different statistical methods were identified. Twenty-nine studies analysed each of the questionnaire sub-dimensions without type I error adjustment. Thirteen studies repeated the HRQoL analysis at each assessment time again without type I error adjustment. Only 8 studies used methods suitable for repeated measurements. Our findings show a lack of consistency in statistical methods for analysing HRQoL data. Problems related to multiple comparisons were rarely considered leading to a high risk of false positive results. It is therefore critical that international recommendations for improving such statistical practices are developed. Copyright © 2017. Published by Elsevier Ltd.

Applying Bayesian statistics to the study of psychological trauma: A suggestion for future research.

PubMed

Yalch, Matthew M

2016-03-01

Several contemporary researchers have noted the virtues of Bayesian methods of data analysis. Although debates continue about whether conventional or Bayesian statistics is the "better" approach for researchers in general, there are reasons why Bayesian methods may be well suited to the study of psychological trauma in particular. This article describes how Bayesian statistics offers practical solutions to the problems of data non-normality, small sample size, and missing data common in research on psychological trauma. After a discussion of these problems and the effects they have on trauma research, this article explains the basic philosophical and statistical foundations of Bayesian statistics and how it provides solutions to these problems using an applied example. Results of the literature review and the accompanying example indicates the utility of Bayesian statistics in addressing problems common in trauma research. Bayesian statistics provides a set of methodological tools and a broader philosophical framework that is useful for trauma researchers. Methodological resources are also provided so that interested readers can learn more. (c) 2016 APA, all rights reserved).

Study/Experimental/Research Design: Much More Than Statistics

PubMed Central

Knight, Kenneth L.

2010-01-01

Abstract Context: The purpose of study, experimental, or research design in scientific manuscripts has changed significantly over the years. It has evolved from an explanation of the design of the experiment (ie, data gathering or acquisition) to an explanation of the statistical analysis. This practice makes “Methods” sections hard to read and understand. Objective: To clarify the difference between study design and statistical analysis, to show the advantages of a properly written study design on article comprehension, and to encourage authors to correctly describe study designs. Description: The role of study design is explored from the introduction of the concept by Fisher through modern-day scientists and the AMA Manual of Style. At one time, when experiments were simpler, the study design and statistical design were identical or very similar. With the complex research that is common today, which often includes manipulating variables to create new variables and the multiple (and different) analyses of a single data set, data collection is very different than statistical design. Thus, both a study design and a statistical design are necessary. Advantages: Scientific manuscripts will be much easier to read and comprehend. A proper experimental design serves as a road map to the study methods, helping readers to understand more clearly how the data were obtained and, therefore, assisting them in properly analyzing the results. PMID:20064054

Joint probability of statistical success of multiple phase III trials.

PubMed

Zhang, Jianliang; Zhang, Jenny J

2013-01-01

In drug development, after completion of phase II proof-of-concept trials, the sponsor needs to make a go/no-go decision to start expensive phase III trials. The probability of statistical success (PoSS) of the phase III trials based on data from earlier studies is an important factor in that decision-making process. Instead of statistical power, the predictive power of a phase III trial, which takes into account the uncertainty in the estimation of treatment effect from earlier studies, has been proposed to evaluate the PoSS of a single trial. However, regulatory authorities generally require statistical significance in two (or more) trials for marketing licensure. We show that the predictive statistics of two future trials are statistically correlated through use of the common observed data from earlier studies. Thus, the joint predictive power should not be evaluated as a simplistic product of the predictive powers of the individual trials. We develop the relevant formulae for the appropriate evaluation of the joint predictive power and provide numerical examples. Our methodology is further extended to the more complex phase III development scenario comprising more than two (K > 2) trials, that is, the evaluation of the PoSS of at least k₀ (k₀≤ K) trials from a program of K total trials. Copyright © 2013 John Wiley & Sons, Ltd.

Pooling sexes when assessing ground reaction forces during walking: Statistical Parametric Mapping versus traditional approach.

PubMed

Castro, Marcelo P; Pataky, Todd C; Sole, Gisela; Vilas-Boas, Joao Paulo

2015-07-16

Ground reaction force (GRF) data from men and women are commonly pooled for analyses. However, it may not be justifiable to pool sexes on the basis of discrete parameters extracted from continuous GRF gait waveforms because this can miss continuous effects. Forty healthy participants (20 men and 20 women) walked at a cadence of 100 steps per minute across two force plates, recording GRFs. Two statistical methods were used to test the null hypothesis of no mean GRF differences between sexes: (i) Statistical Parametric Mapping-using the entire three-component GRF waveform; and (ii) traditional approach-using the first and second vertical GRF peaks. Statistical Parametric Mapping results suggested large sex differences, which post-hoc analyses suggested were due predominantly to higher anterior-posterior and vertical GRFs in early stance in women compared to men. Statistically significant differences were observed for the first GRF peak and similar values for the second GRF peak. These contrasting results emphasise that different parts of the waveform have different signal strengths and thus that one may use the traditional approach to choose arbitrary metrics and make arbitrary conclusions. We suggest that researchers and clinicians consider both the entire gait waveforms and sex-specificity when analysing GRF data. Copyright © 2015 Elsevier Ltd. All rights reserved.

Single, double or multiple-injection techniques for non-ultrasound guided axillary brachial plexus block in adults undergoing surgery of the lower arm.

PubMed

Chin, Ki Jinn; Alakkad, Husni; Cubillos, Javier E

2013-08-08

Regional anaesthesia comprising axillary block of the brachial plexus is a common anaesthetic technique for distal upper limb surgery. This is an update of a review first published in 2006 and updated in 2011. To compare the relative effects (benefits and harms) of three injection techniques (single, double and multiple) of axillary block of the brachial plexus for distal upper extremity surgery. We considered these effects primarily in terms of anaesthetic effectiveness; the complication rate (neurological and vascular); and pain and discomfort caused by performance of the block. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and reference lists of trials. We contacted trial authors. The date of the last search was March 2013 (updated from March 2011). We included randomized controlled trials that compared double with single-injection techniques, multiple with single-injection techniques, or multiple with double-injection techniques for axillary block in adults undergoing surgery of the distal upper limb. We excluded trials using ultrasound-guided techniques. Independent study selection, risk of bias assessment and data extraction were performed by at least two investigators. We undertook meta-analysis. The 21 included trials involved a total of 2148 participants who received regional anaesthesia for hand, wrist, forearm or elbow surgery. Risk of bias assessment indicated that trial design and conduct were generally adequate; the most common areas of weakness were in blinding and allocation concealment.Eight trials comparing double versus single injections showed a statistically significant decrease in primary anaesthesia failure (risk ratio (RR 0.51), 95% confidence interval (CI) 0.30 to 0.85). Subgroup analysis by method of nerve location showed that the effect size was greater when neurostimulation was used rather than the transarterial technique.Eight trials comparing multiple with single injections showed a statistically significant decrease in primary anaesthesia failure (RR 0.25, 95% CI 0.14 to 0.44) and of incomplete motor block (RR 0.61, 95% CI 0.39 to 0.96) in the multiple injection group.Eleven trials comparing multiple with double injections showed a statistically significant decrease in primary anaesthesia failure (RR 0.28, 95% CI 0.20 to 0.40) and of incomplete motor block (RR 0.55, 95% CI 0.36 to 0.85) in the multiple injection group.Tourniquet pain was significantly reduced with multiple injections compared with double injections (RR 0.53, 95% CI 0.33 to 0.84). Otherwise there were no statistically significant differences between groups in any of the three comparisons on secondary analgesia failure, complications and patient discomfort. The time for block performance was significantly shorter for single and double injections compared with multiple injections. This review provides evidence that multiple-injection techniques using nerve stimulation for axillary plexus block produce more effective anaesthesia than either double or single-injection techniques. However, there was insufficient evidence for a significant difference in other outcomes, including safety.

Common Bile Duct (CBD) diameter in opium-addicted men: Comparison with non-addict controls.

PubMed

Zahedi-Nejad, Nina; Narouei, Shahin; Fahimy, Farnaz

2010-07-01

Opium and its derivatives are widely abused throughout the world. Recent case reports and a few limited studies have suggested that opiates cause dilation of the common bile duct of the abusers. Our case-control study, lasting 7.5 months, investigated 121 male adult addicts and 142 non-addicted controls for biliary tract diameters, using ultrasonography. The study was conducted in Bahonar Hospital in Kerman. Neither the addiction cases nor the non-addict controls revealed any hepatobiliary tract symptoms. The subjects were asked to fill in a questionnaire. After the exclusion of the symptomatic cases, ultrasound examinations were carried out and the findings from questionnaires and US examinations were recorded. The mean ±SD diameter of the common bile duct was 4.78±2.58 for addicts and 3.37±2.25 for non-addicts. CBD wall thickness was 1.969±0.61 mm in addicts versus 1.73±0.631 in non-addicts. The differences were statistically significant. According to the multivariate analysis, the duration of opium abuse was a significant factor. We concluded that CBD dilation and increased CBD wall thickness can be expected in people with a prolonged history of opiate addiction.

Statistical significance versus clinical relevance.

PubMed

van Rijn, Marieke H C; Bech, Anneke; Bouyer, Jean; van den Brand, Jan A J G

2017-04-01

In March this year, the American Statistical Association (ASA) posted a statement on the correct use of P-values, in response to a growing concern that the P-value is commonly misused and misinterpreted. We aim to translate these warnings given by the ASA into a language more easily understood by clinicians and researchers without a deep background in statistics. Moreover, we intend to illustrate the limitations of P-values, even when used and interpreted correctly, and bring more attention to the clinical relevance of study findings using two recently reported studies as examples. We argue that P-values are often misinterpreted. A common mistake is saying that P < 0.05 means that the null hypothesis is false, and P ≥0.05 means that the null hypothesis is true. The correct interpretation of a P-value of 0.05 is that if the null hypothesis were indeed true, a similar or more extreme result would occur 5% of the times upon repeating the study in a similar sample. In other words, the P-value informs about the likelihood of the data given the null hypothesis and not the other way around. A possible alternative related to the P-value is the confidence interval (CI). It provides more information on the magnitude of an effect and the imprecision with which that effect was estimated. However, there is no magic bullet to replace P-values and stop erroneous interpretation of scientific results. Scientists and readers alike should make themselves familiar with the correct, nuanced interpretation of statistical tests, P-values and CIs. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Statistical tests to compare motif count exceptionalities

PubMed Central

Robin, Stéphane; Schbath, Sophie; Vandewalle, Vincent

2007-01-01

Background Finding over- or under-represented motifs in biological sequences is now a common task in genomics. Thanks to p-value calculation for motif counts, exceptional motifs are identified and represent candidate functional motifs. The present work addresses the related question of comparing the exceptionality of one motif in two different sequences. Just comparing the motif count p-values in each sequence is indeed not sufficient to decide if this motif is significantly more exceptional in one sequence compared to the other one. A statistical test is required. Results We develop and analyze two statistical tests, an exact binomial one and an asymptotic likelihood ratio test, to decide whether the exceptionality of a given motif is equivalent or significantly different in two sequences of interest. For that purpose, motif occurrences are modeled by Poisson processes, with a special care for overlapping motifs. Both tests can take the sequence compositions into account. As an illustration, we compare the octamer exceptionalities in the Escherichia coli K-12 backbone versus variable strain-specific loops. Conclusion The exact binomial test is particularly adapted for small counts. For large counts, we advise to use the likelihood ratio test which is asymptotic but strongly correlated with the exact binomial test and very simple to use. PMID:17346349

Subgingival Microbiota in White Patients With Desquamative Gingivitis: A Cross-Sectional Study.

PubMed

Arduino, Paolo G; Romano, Federica; Sasia, Danilo; Broccoletti, Roberto; Ricceri, Fulvio; Barbui, Anna Maria; Brossa, Silvia; Cipriani, Raffaella; Cricenti, Luca; Cabras, Marco; Aimetti, Mario

2017-07-01

Presence of epithelial desquamation, erythema, and erosions on gingival tissue is usually described in the literature as desquamative gingivitis (DG). A wide range of autoimmune/dermatologic disorders can manifest as DG, although the two more common are oral lichen planus and mucous membrane pemphigoid. The aim of this study is to investigate prevalence of 11 periodontopathogenic microorganisms in patients with DG and to compare it with the microbiologic status of individuals affected by plaque-induced gingivitis (pGI). Cross-sectional clinical and microbiologic data were obtained from 66 patients (33 in each group). Subgingival plaque samples were analyzed using semiquantitative polymerase chain reaction analysis. Statistically significant difference, but with little clinical significance, was observed in gingival conditions between the two groups, probably due to the worse home control hygiene of patients with DG. Prevalence and levels of Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum/periodonticum were statistically higher in samples from patients with DG than in those with pGI. In multivariate regression models, subgingival colonization of A. actinomycetemcomitans and F. nucleatum/periodonticum was not statistically associated with DG, whereas, high levels of E. corrodens were associated with 13-fold increased odds for DG. Microbiologic differences were found in subgingival plaque for patients with DG and pGI. This may suggest possible association between periodontal pathogens and DG.

Modification of Occupational Exposures on Bladder Cancer Risk by Common Genetic Polymorphisms.

PubMed

Figueroa, Jonine D; Koutros, Stella; Colt, Joanne S; Kogevinas, Manolis; Garcia-Closas, Montserrat; Real, Francisco X; Friesen, Melissa C; Baris, Dalsu; Stewart, Patricia; Schwenn, Molly; Johnson, Alison; Karagas, Margaret R; Armenti, Karla R; Moore, Lee E; Schned, Alan; Lenz, Petra; Prokunina-Olsson, Ludmila; Banday, A Rouf; Paquin, Ashley; Ylaya, Kris; Chung, Joon-Yong; Hewitt, Stephen M; Nickerson, Michael L; Tardón, Adonina; Serra, Consol; Carrato, Alfredo; García-Closas, Reina; Lloreta, Josep; Malats, Núria; Fraumeni, Joseph F; Chanock, Stephen J; Chatterjee, Nilanjan; Rothman, Nathaniel; Silverman, Debra T

2015-11-01

Few studies have demonstrated gene/environment interactions in cancer research. Using data on high-risk occupations for 2258 case patients and 2410 control patients from two bladder cancer studies, we observed that three of 16 known or candidate bladder cancer susceptibility variants displayed statistically significant and consistent evidence of additive interactions; specifically, the GSTM1 deletion polymorphism (P interaction ≤ .001), rs11892031 (UGT1A, P interaction = .01), and rs798766 (TMEM129-TACC3-FGFR3, P interaction = .03). There was limited evidence for multiplicative interactions. When we examined detailed data on a prevalent occupational exposure associated with increased bladder cancer risk, straight metalworking fluids, we also observed statistically significant additive interaction for rs798766 (TMEM129-TACC3-FGFR3, P interaction = .02), with the interaction more apparent in patients with tumors positive for FGFR3 expression. All statistical tests were two-sided. The interaction we observed for rs798766 (TMEM129-TACC3-FGFR3) with specific exposure to straight metalworking fluids illustrates the value of integrating germline genetic variation, environmental exposures, and tumor marker data to provide insight into the mechanisms of bladder carcinogenesis. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Spatio-Temporal Patterns of Barmah Forest Virus Disease in Queensland, Australia

PubMed Central

Naish, Suchithra; Hu, Wenbiao; Mengersen, Kerrie; Tong, Shilu

2011-01-01

Background Barmah Forest virus (BFV) disease is a common and wide-spread mosquito-borne disease in Australia. This study investigated the spatio-temporal patterns of BFV disease in Queensland, Australia using geographical information system (GIS) tools and geostatistical analysis. Methods/Principal Findings We calculated the incidence rates and standardised incidence rates of BFV disease. Moran's I statistic was used to assess the spatial autocorrelation of BFV incidences. Spatial dynamics of BFV disease was examined using semi-variogram analysis. Interpolation techniques were applied to visualise and display the spatial distribution of BFV disease in statistical local areas (SLAs) throughout Queensland. Mapping of BFV disease by SLAs reveals the presence of substantial spatio-temporal variation over time. Statistically significant differences in BFV incidence rates were identified among age groups (χ2 = 7587, df = 7327,p<0.01). There was a significant positive spatial autocorrelation of BFV incidence for all four periods, with the Moran's I statistic ranging from 0.1506 to 0.2901 (p<0.01). Semi-variogram analysis and smoothed maps created from interpolation techniques indicate that the pattern of spatial autocorrelation was not homogeneous across the state. Conclusions/Significance This is the first study to examine spatial and temporal variation in the incidence rates of BFV disease across Queensland using GIS and geostatistics. The BFV transmission varied with age and gender, which may be due to exposure rates or behavioural risk factors. There are differences in the spatio-temporal patterns of BFV disease which may be related to local socio-ecological and environmental factors. These research findings may have implications in the BFV disease control and prevention programs in Queensland. PMID:22022430

Disparities in Cervical Cancer Characteristics and Survival Between White Hispanics and White Non-Hispanic Women.

PubMed

Khan, Hafiz M R; Gabbidon, Kemesha; Saxena, Anshul; Abdool-Ghany, Faheema; Dodge, John M; Lenzmeier, Taylor

2016-10-01

Cervical cancer is the second most common cancer among women resulting in nearly 500,000 cases annually. Screening leads to better treatment and survival time. However, human papillomavirus (HPV) exposure, screening, and treatment vary among races and ethnicities in the United States. The purpose of this study is to examine disparities in characteristics of cervical cancer and survival of cases between White Hispanic (WH) and White non-Hispanic (WNH) women in the United States. We used a stratified random sampling method to select cervical cancer patient records from nine states; a simple random sampling method to extract the demographic and disease characteristics data within states from the Surveillance Epidemiology and End Results (SEER) database. We used statistical probability distribution methods for discrete and continuous data. The chi-square test and independent samples t-test were used to evaluate statistically significant differences. Furthermore, the Cox Proportional Regression and the Kaplan-Meier survival estimators were used to compare WH and WNH population survival times in the United States. The samples of WNH and WH women included 4,000 cervical cancer cases from 1973-2009. There were statistically significant differences between ethnicities: marital status (p < 0.001); primary site of cancer (p < 0.001); lymph node involvement (p < 0.001); grading and differentiation (p < 0.0001); and tumor behavior (p < 0.001). The mean age of diagnosis for both groups showed no statistical differences. However, the mean survival time for WNH was 221.7 (standard deviation [SD] = 118.1) months and for WH was 190.3 (SD = 120.3), which differed significantly (p < 0.001). Clear disparities exist in risk factors, cervical cancer characteristics, and survival time between WH and WNH women.

Immunohistochemical evaluation of inducible nitric oxide synthase in the epithelial lining of odontogenic cysts: A qualitative and quantitative analysis.

PubMed

Akshatha, B K; Karuppiah, Karpagaselvi; Manjunath, G S; Kumarswamy, Jayalakshmi; Papaiah, Lokesh; Rao, Jyothi

2017-01-01

The three common odontogenic cysts include radicular cysts (RCs), dentigerous cysts (DCs), and odontogenic keratocysts (OKCs). Among these 3 cysts, OKC is recently been classified as benign keratocystic odontogenic tumor attributing to its aggressive behavior, recurrence rate, and malignant potential. The present study involved qualitative and quantitative analysis of inducible nitric oxide synthase (iNOS) expression in epithelial lining of RCs, DCs, and OKCs, compare iNOS expression in epithelial linings of all the 3 cysts and determined overexpression of iNOS in OKCs which might contribute to its aggressive behavior and malignant potential. The present study is to investigate the role of iNOS in the pathogenesis of OKCs, DCs, and RCs by evaluating the iNOS expression in the epithelial lining of these cysts. Analysis of iNOS expression in epithelial lining cells of 20 RCs, 20 DCs, and 20 OKCs using immunohistochemistry done. The percentage of positive cells and intensity of stain was assessed and compared among all the 3 cysts using contingency coefficient. Kappa statistics for the two observers were computed for finding interobserver agreement. The percentage of iNOS-positive cells was found to be remarkably high in OKCs (12/20) -57.1% as compared to RCs (6/20) - 28.6% and DCs (3/20) - 14.3%. The interobserver agreement for iNOS-positive percentage cells was arrived with kappa values with OKCs → Statistically significant ( P > 0.000), RCs → statistically significant ( P > 0.001) with no significant values for DCs. No statistical difference exists among 3 study samples in regard to the intensity of staining with iNOS. Increased iNOS expression in OKCs may contribute to bone resorption and accumulation of wild-type p53, hence, making OKCs more aggressive.

Prevalence and correlates of tobacco use among urban adult men in India: a comparison of slum dwellers vs non-slum dwellers.

PubMed

Rooban, T; Joshua, Elizabeth; Rao, Umadevi K; Ranganathan, K

2012-01-01

Tobacco use is reported to be rampant in urban slums in developing countries. Demographical variations in tobacco use between males living in urban slums vs those living in non-slum areas in India has not been reported, and this study was undertaken to address this issue. Secondary data analysis of National Family Health Survey-3 (NFHS-3) was undertaken to study demographical variations in tobacco use between urban slum dwellers and non-slum dwellers in eight Indian cities. Demographic determinants for use of smoking and chewing forms of tobacco in the two groups were analyzed. SPSS version 16.0 (SPSS Inc., IL, USA) was used for statistical analysis. The study population comprised 6887 (41.8%) males from slum areas and 9588 (58.2%) from non-slum areas of eight urban cities. Cigarette/beedi smoking was the commonest form of tobacco use among the study population. Pan masala use was the least common form of smokeless tobacco use, next only to snuff. There was a high statistical significance observed within the various demographic parameter studied in both the slum and non-slum dwelling males in study population. However, on studying the differences between the two groups, it was observed that statistical significance of P≤.001 was observed with age (15-49), secondary education, religion, household structure and marital status. The difference between the two groups in the mean number of cigarettes/beedis smoked was not statistically significant (P=.598). Male slum dwellers are a distinct urban population, whose health needs assessment requires a different approach than that for non-slum dwellers who often can afford the services that an urban Indian city can offer.

Ocular disorders in children with spastic subtype of cerebral palsy.

PubMed

Ozturk, A Taylan; Berk, A Tulin; Yaman, Aylin

2013-01-01

To document common ocular abnormalities in children with spastic subtype of cerebral palsy (CP) and to find out whether any correlation exists between their occurance and etiologic factors. Totally 194 patients with the diagnosis of spastic type CP were enrolled in this retrospective study. Detailed ophthalmic examinations were performed. Demographic data and neuroradiological findings were documented. Kruskal-Wallis, Mann Whitney U, Pearson Chi-square tests and Student's t tests were used in the statistical analysis. The mean age was 64.7±44.2 months on the first ophthalmic examination. Prevalences of diplegia (47.4%) and tetraplegia (36.1%) were found to be higher than the frequency of hemiplegia (16.5%) in our study population. Etiologic factor was asphyxia in 60.8% of the patients. Abnormal ocular findings were present in 78.9% of the patients. Statistically significant poor vision was detected in tetraplegia group among all the spastic ubtypes of CP (P=0.000). Anisometropia and significant refractive error were found in 14.4% and 70.1% of the patients, respectively. Thirty-six children (18.6%) had nystagmus and 107 children (55.2%) had strabismus. Lower gestational age and birth weight were statistically higher in patients with esotropia than exotropia (P=0.009 and P=0.024, respectively). Abnormal morphology of the optic disc was present in 152 eyes (39.2%). Severe periventricular leukomalacia (PVL) was found in 48 patients and statistically significant poor vision was detected in the presence of PVL (P=0.000). Spastic diplegic or tetraplegic CP patients with positive neuroradiological symptoms, younger gestational age and lower birth weight ought to have detailed ophthalmic examinations as early as possible to provide best visual rehabilitation.

Adopting a Patient-Centered Approach to Primary Outcome Analysis of Acute Stroke Trials by Use of a Utility-Weighted Modified Rankin Scale

PubMed Central

Chaisinanunkul, Napasri; Adeoye, Opeolu; Lewis, Roger J.; Grotta, James C.; Broderick, Joseph; Jovin, Tudor G.; Nogueira, Raul G.; Elm, Jordan; Graves, Todd; Berry, Scott; Lees, Kennedy R.; Barreto, Andrew D.; Saver, Jeffrey L.

2015-01-01

Background and Purpose Although the modified Rankin Scale (mRS) is the most commonly employed primary endpoint in acute stroke trials, its power is limited when analyzed in dichotomized fashion and its indication of effect size challenging to interpret when analyzed ordinally. Weighting the seven Rankin levels by utilities may improve scale interpretability while preserving statistical power. Methods A utility weighted mRS (UW-mRS) was derived by averaging values from time-tradeoff (patient centered) and person-tradeoff (clinician centered) studies. The UW-mRS, standard ordinal mRS, and dichotomized mRS were applied to 11 trials or meta-analyses of acute stroke treatments, including lytic, endovascular reperfusion, blood pressure moderation, and hemicraniectomy interventions. Results Utility values were: mRS 0–1.0; mRS 1 - 0.91; mRS 2 - 0.76; mRS 3 - 0.65; mRS 4 - 0.33; mRS 5 & 6 - 0. For trials with unidirectional treatment effects, the UW-mRS paralleled the ordinal mRS and outperformed dichotomous mRS analyses. Both the UW-mRS and the ordinal mRS were statistically significant in six of eight unidirectional effect trials, while dichotomous analyses were statistically significant in two to four of eight. In bidirectional effect trials, both the UW-mRS and ordinal tests captured the divergent treatment effects by showing neutral results whereas some dichotomized analyses showed positive results. Mean utility differences in trials with statistically significant positive results ranged from 0.026 to 0.249. Conclusion A utility-weighted mRS performs similarly to the standard ordinal mRS in detecting treatment effects in actual stroke trials and ensures the quantitative outcome is a valid reflection of patient-centered benefits. PMID:26138130

Undergraduate Statistics Education and the National Science Foundation

ERIC Educational Resources Information Center

Hall, Megan R.; Rowell, Ginger Holmes

2008-01-01

This paper describes 25 National Science Foundation supported projects that have innovations designed to improve education for students majoring or minoring in statistics. The characteristics of these projects and the common themes which emerge are compared with the American Statistical Association's (ASA) guidelines for developing statistics…

A Review of the Study Designs and Statistical Methods Used in the Determination of Predictors of All-Cause Mortality in HIV-Infected Cohorts: 2002–2011

PubMed Central

Otwombe, Kennedy N.; Petzold, Max; Martinson, Neil; Chirwa, Tobias

2014-01-01

Background Research in the predictors of all-cause mortality in HIV-infected people has widely been reported in literature. Making an informed decision requires understanding the methods used. Objectives We present a review on study designs, statistical methods and their appropriateness in original articles reporting on predictors of all-cause mortality in HIV-infected people between January 2002 and December 2011. Statistical methods were compared between 2002–2006 and 2007–2011. Time-to-event analysis techniques were considered appropriate. Data Sources Pubmed/Medline. Study Eligibility Criteria Original English-language articles were abstracted. Letters to the editor, editorials, reviews, systematic reviews, meta-analysis, case reports and any other ineligible articles were excluded. Results A total of 189 studies were identified (n = 91 in 2002–2006 and n = 98 in 2007–2011) out of which 130 (69%) were prospective and 56 (30%) were retrospective. One hundred and eighty-two (96%) studies described their sample using descriptive statistics while 32 (17%) made comparisons using t-tests. Kaplan-Meier methods for time-to-event analysis were commonly used in the earlier period (n = 69, 76% vs. n = 53, 54%, p = 0.002). Predictors of mortality in the two periods were commonly determined using Cox regression analysis (n = 67, 75% vs. n = 63, 64%, p = 0.12). Only 7 (4%) used advanced survival analysis methods of Cox regression analysis with frailty in which 6 (3%) were used in the later period. Thirty-two (17%) used logistic regression while 8 (4%) used other methods. There were significantly more articles from the first period using appropriate methods compared to the second (n = 80, 88% vs. n = 69, 70%, p-value = 0.003). Conclusion Descriptive statistics and survival analysis techniques remain the most common methods of analysis in publications on predictors of all-cause mortality in HIV-infected cohorts while prospective research designs are favoured. Sophisticated techniques of time-dependent Cox regression and Cox regression with frailty are scarce. This motivates for more training in the use of advanced time-to-event methods. PMID:24498313

Limitations of Poisson statistics in describing radioactive decay.

PubMed

Sitek, Arkadiusz; Celler, Anna M

2015-12-01

The assumption that nuclear decays are governed by Poisson statistics is an approximation. This approximation becomes unjustified when data acquisition times longer than or even comparable with the half-lives of the radioisotope in the sample are considered. In this work, the limits of the Poisson-statistics approximation are investigated. The formalism for the statistics of radioactive decay based on binomial distribution is derived. The theoretical factor describing the deviation of variance of the number of decays predicated by the Poisson distribution from the true variance is defined and investigated for several commonly used radiotracers such as (18)F, (15)O, (82)Rb, (13)N, (99m)Tc, (123)I, and (201)Tl. The variance of the number of decays estimated using the Poisson distribution is significantly different than the true variance for a 5-minute observation time of (11)C, (15)O, (13)N, and (82)Rb. Durations of nuclear medicine studies often are relatively long; they may be even a few times longer than the half-lives of some short-lived radiotracers. Our study shows that in such situations the Poisson statistics is unsuitable and should not be applied to describe the statistics of the number of decays in radioactive samples. However, the above statement does not directly apply to counting statistics at the level of event detection. Low sensitivities of detectors which are used in imaging studies make the Poisson approximation near perfect. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Normality Tests for Statistical Analysis: A Guide for Non-Statisticians

PubMed Central

Ghasemi, Asghar; Zahediasl, Saleh

2012-01-01

Statistical errors are common in scientific literature and about 50% of the published articles have at least one error. The assumption of normality needs to be checked for many statistical procedures, namely parametric tests, because their validity depends on it. The aim of this commentary is to overview checking for normality in statistical analysis using SPSS. PMID:23843808

Prevalence of sexual dysfunction among females in a university community in Enugu, Nigeria.

PubMed

Nwagha, U I; Oguanuo, T C; Ekwuazi, K; Olubobokun, T O; Nwagha, T U; Onyebuchi, A K; Ezeonu, P O; Nwadike, K

2014-01-01

Female sexual dysfunction is a common, condition that significantly reduces the quality-of-life of the affected persons. Unfortunately, because of the veil of secrecy that shrouds discussions on human sexuality, there has been limited research on this topic in some sociocultural settings. The aim was to determine the prevalence and some sociodemographic factors associated with sexual dysfunction in females in a university community at the University of Nigeria, Enugu Campus, Enugu State, Nigeria. This is a cross-sectional study involving 500 females recruited randomly in a tertiary institution in Nigeria. A self-administered structured pretested questionnaire on sexual activity was administered (the Female Sexual Function Index [FSFI]). Statistical analysis was performed using SPSS software package (Version 17.0, Chicago, IL, USA). Multiple logistic regression was used to determine the relationship between the sociodemographic factors, and the total FSFI scores dichotomized as normal and reduced sexual function. In addition, multiple linear regression was used to determine the relationship between the six different domains scores and the continuous values of the total score. For all, calculations, P < 0.05 was considered as statistically significant at 95% confidence interval (CI). The prevalence of female sexual dysfunction (FSFI score ≤ 26.50) was 53.3%. The highest prevalence occurred in the 41-50 years age group (73.3%; 66/90), married and living together 56.4% (123/218) and had postsecondary education (56.1%; 137/244). Only age significantly predicted female sexual function (P = 0.007; 95% CI; 0.691-0.943). Marital status, religion, ethnic group, and educational qualification had no significant effect (P < 0.05). The total FSFI significantly increase as desire increases (P = 0.002; 95% CI = 0.817-3.573). Female sexual dysfunction is common in the university environment, with the highest prevalence occurring in 41-50 years age group.

Comparison of Early-period Results of Nasal Splint and Merocel Nasal Packs in Septoplasty

PubMed Central

Bingöl, Fatih; Budak, Ali; Şimşek, Eda; Kılıç, Korhan; Bingöl, Buket Özel

2017-01-01

Objective Several types of nasal packs are used postoperatively in septoplasty. In this study, we compared two commonly used nasal packing materials, the intranasal septal splint with airway and Merocel tampon, in terms of pain, bleeding, nasal obstruction, eating difficulties, discomfort in sleep, and pain and bleeding during removal of packing in the early period. Methods The study group included 60 patients undergoing septoplasty. Patients were divided into two groups (n=30 in each group). An intranasal splint with airway was used for the patients in the first group after septoplasty, while Merocel nasal packing was used for the second group. Patients were investigated in terms of seven different factors - pain, bleeding while the tampon was in place, nasal obstruction, eating difficulties, night sleep, pain during removal of the nasal packing, and bleeding after removal of packing. Results There was no statistically significant difference between the groups in terms of pain 24 hours after operation (p=0.05), while visual analog scale (VAS) scores for nasal obstruction, night sleep, eating difficulties, and pain during packing removal were lower in the nasal splint group with a statistically significant difference (p<0.05). There was no statistically significant difference between the groups in terms of postoperative bleeding (p=0.23). Significantly less bleeding occurred during removal of the packing in the nasal splint group (p<0.05). Conclusion Our study indicates that the nasal splint was more comfortable and effective in terms of causing lesser bleeding and pain during removal of packing. PMID:29392071

Early cognitive development in children born to women with epilepsy: a prospective report.

PubMed

Bromley, Rebecca L; Mawer, George; Love, Jenna; Kelly, James; Purdy, Laura; McEwan, Lauren; Briggs, Maria; Clayton-Smith, Jill; Shi, Xin; Sin, Xin; Baker, Gus A

2010-10-01

In this prospective study the early cognitive development of children born to women with epilepsy (n = 198) was assessed and compared to a group of children representative of the general population (n = 230). The children were assessed when younger than the age of 2 years using the Griffiths Mental Development Scales, either in their local participating hospital or in their home. The assessments were completed by an assessor who was blinded to whether the child's mother had epilepsy and to antiepileptic drug type. Children exposed to sodium valproate had a statistically significant increased risk of delayed early development in comparison to the control children. Linear regression analysis showed a statistically significant effect of sodium valproate exposure on the child's overall developmental level that was not accounted for by confounding variables. Delayed early development is also noted for children within an ad hoc group of less commonly utilized antiepileptic drugs, although conclusions cannot be drawn due to the size of this group (n = 13). Children exposed to either carbamazepine or lamotrigine in utero did not differ significantly in their overall developmental ability. Differences noted in specific developmental areas for these two groups were not statistically significant after the control for confounders such as socioeconomic status and maternal IQ. Women with epilepsy should be informed of the risks posed to their potential offspring prior to pregnancy to allow for informed decisions regarding treatment. Children exposed in utero to antiepileptic drugs should be monitored throughout childhood to allow for early intervention when necessary. Wiley Periodicals, Inc. © 2010 International League Against Epilepsy.

Effectiveness of Tongue-lip Adhesion for Obstructive Sleep Apnea in Infants With Robin Sequence Measured by Polysomnography.

PubMed

Resnick, Cory M; Dentino, Kelley; Katz, Eliot; Mulliken, John B; Padwa, Bonnie L

2016-09-01

Tongue-lip adhesion (TLA) is commonly used to relieve obstructive sleep apnea (OSA) in infants with Robin sequence (RS), but few studies have evaluated its efficacy with objective measures. The purpose of this study was to measure TLA outcomes using polysomnography. Our hypothesis was that TLA relieves OSA in most infants. This is a retrospective study of infants with RS who underwent TLA from 2011 to 2014 and had at least a postoperative polysomnogram. Predictor variables included demographic and birth characteristics, surgeon, syndromic diagnosis, GILLS score, preoperative OSA severity, and clinical course. A successful outcome was defined as minimal OSA (apnea-hypopnea index score < 5) on postoperative polysomnogram and no need for additional airway intervention. Descriptive, bivariate, and regression statistics were computed, and statistical significance was set at P < .05. Eighteen subjects who had TLA at a mean age of 28 ± 4.7 days were included. Thirteen (72.2%) had a confirmed or suspected syndrome, and the mean GILLS score was 3 ± 0.3. All parameters trended toward improvement from the preoperative to postoperative polysomnograms, and improvement in OSA severity, oxygen saturation nadir, and arousals per hour was statistically significant (P < .02). This effect was significant across categories of surgeon, syndrome, and GILLS score. Nine subjects (50%) met the criteria for a successful outcome. Bivariate and regression analyses did not demonstrate a significant relationship between success and any predictor variable. TLA improved airway obstruction in all infants with RS but resolved OSA in only nine patients, and success was unpredictable.

More Cancer Types - SEER Cancer Stat Facts

Cancer.gov

Cancer Statistical Fact Sheets are summaries of common cancer types developed to provide an overview of frequently-requested cancer statistics including incidence, mortality, survival, stage, prevalence, and lifetime risk.

Projected changes, climate change signal, and uncertainties in the CMIP5-based projections of ocean surface wave heights

NASA Astrophysics Data System (ADS)

Wang, Xiaolan; Feng, Yang; Swail, Val R.

2016-04-01

Ocean surface waves can be major hazards in coastal and offshore activities. However, wave observations are available only at limited locations and cover only the recent few decades. Also, there exists very limited information on ocean wave behavior in response to climate change, because such information is not simulated in current global climate models. In a recent study, we used a multivariate regression model with lagged dependent variable to make statistical global projections of changes in significant wave heights (Hs) using mean sea level pressure (SLP) information from 20 CMIP5 climate models for the twenty-first century. The statistical model was calibrated and validated using the ERA-Interim reanalysis of Hs and SLP for the period 1981-2010. The results show Hs increases in the tropics (especially in the eastern tropical Pacific) and in southern hemisphere high-latitudes. Under the projected 2070-2099 climate condition of the RCP8.5 scenario, the occurrence frequency of the present-day one-in-10-year extreme wave heights is likely to double or triple in several coastal regions around the world (e.g., the Chilean coast, Gulf of Oman, Gulf of Bengal, Gulf of Mexico). More recently, we used the analysis of variance approaches to quantify the climate change signal and uncertainty in multi-model ensembles of statistical Hs simulations globally, which are based on the CMIP5 historical, RCP4.5 and RCP8.5 forcing scenario simulations of SLP. In a 4-model 3-run ensemble, the 4-model common signal of climate change is found to strengthen over time, as would be expected. For the historical followed by RCP8.5 scenario, the common signal in annual mean Hs is found to be significant over 16.6%, 55.0% and 82.2% of the area by year 2005, 2050 and 2099, respectively. For the annual maximum, the signal is much weaker. The signal is strongest in the eastern tropical Pacific, featuring significant increases in both the annual mean and maximum of Hs in this region. The climate model uncertainty (i.e., inter-model variability) is significant over 99.9% of the area; its magnitude is comparable to or greater than the climate change signal by 2099 over most areas, except in the eastern tropical Pacific where the signal is much larger. In a 20-model 2-scenario single-run ensemble of statistical Hs simulations for the period 2006-2099, the model uncertainty is found to be significant globally; it is about 10 times as large as the scenario uncertainty between RCP4.5 and RCP8.5 scenarios.

Granulocyte, monocyte and blast immunophenotype abnormalities in acute myeloid leukemia with myelodysplasia-related changes.

PubMed

Ayar, Sonali P; Ravula, Sreelakshmi; Polski, Jacek M

2014-01-01

Little literature exists regarding granulocyte and monocyte immunophenotype abnormalities in Acute Myeloid Leukemia (AML). We hypothesized that granulocyte and monocyte immunophenotype abnormalities are common in AML, and especially in AML with myelodysplasia-related changes (AMLMRC). Bone marrow or peripheral blood specimens from 48 cases of AML and 22 cases of control specimens were analyzed by flow cytometric immunophenotyping. Granulocyte, monocyte, and blast immunophenotype abnormalities were compared between cases of AML versus controls and AMLMRC versus AML without myelodysplasia. The results revealed that granulocyte, monocyte, and blast abnormalities were more common in AMLMRC than in AML without myelodysplasia or control cases. The difference reached statistical significance for abnormalities of granulocytes and abnormalities in all cells of interest. From the numerous individual abnormalities, only CD25 expression in blasts was significantly more prevalent in AMLMRC in this study. We conclude that detection of granulocyte, monocyte, and blast immunophenotype abnormalities can contribute to the diagnosis of AMLMRC.

Biotoxicity of commonly used root canal sealers: A meta-analysis.

PubMed

Kaur, Amandeep; Shah, Naseem; Logani, Ajay; Mishra, Navin

2015-01-01

The main objective of a root canal sealer is to provide a fluid tight seal. The purpose of this systematic meta-analysis was to determine the relative toxicity of commonly used root canal sealers like zinc oxide eugenol, calcium hydroxide, and resin-based sealers. An online search was conducted in peer-reviewed journals listed in PubMed, Cochrane, EBSCO, and IndMed databases between 2000 and 2012). Statistical analysis was carried out by using analysis of variance (ANOVA) followed by post-hoc comparison by Bonferroni method. The comparison between toxicity at 24 h and between 3 and 7 days was done by using paired t-test for each sealer. At 24 h, the relative biotoxicity of the three sealers reported was insignificant (P- value 0.29), but the difference in toxicity was found significant (P < 0.001) after 3 days. Calcium hydroxide sealer and zinc oxide eugenol were found to be significantly biotoxic as compared to resin-based sealers after 3 days.

Biotoxicity of commonly used root canal sealers: A meta-analysis

PubMed Central

Kaur, Amandeep; Shah, Naseem; Logani, Ajay; Mishra, Navin

2015-01-01

Introduction: The main objective of a root canal sealer is to provide a fluid tight seal. The purpose of this systematic meta-analysis was to determine the relative toxicity of commonly used root canal sealers like zinc oxide eugenol, calcium hydroxide, and resin-based sealers. Materials and Methods: An online search was conducted in peer-reviewed journals listed in PubMed, Cochrane, EBSCO, and IndMed databases between 2000 and 2012). Statistical analysis was carried out by using analysis of variance (ANOVA) followed by post-hoc comparison by Bonferroni method. The comparison between toxicity at 24 h and between 3 and 7 days was done by using paired t-test for each sealer. Results: At 24 h, the relative biotoxicity of the three sealers reported was insignificant (P- value 0.29), but the difference in toxicity was found significant (P < 0.001) after 3 days. Conclusion: Calcium hydroxide sealer and zinc oxide eugenol were found to be significantly biotoxic as compared to resin-based sealers after 3 days. PMID:25829682

Transcriptome profiling analysis reveals biomarkers in colon cancer samples of various differentiation

PubMed Central

Yu, Tonghu; Zhang, Huaping; Qi, Hong

2018-01-01

The aim of the present study was to investigate more colon cancer-related genes in different stages. Gene expression profile E-GEOD-62932 was extracted for differentially expressed gene (DEG) screening. Series test of cluster analysis was used to obtain significant trending models. Based on the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases, functional and pathway enrichment analysis were processed and a pathway relation network was constructed. Gene co-expression network and gene signal network were constructed for common DEGs. The DEGs with the same trend were clustered and in total, 16 clusters with statistical significance were obtained. The screened DEGs were enriched into small molecule metabolic process and metabolic pathways. The pathway relation network was constructed with 57 nodes. A total of 328 common DEGs were obtained. Gene signal network was constructed with 71 nodes. Gene co-expression network was constructed with 161 nodes and 211 edges. ABCD3, CPT2, AGL and JAM2 are potential biomarkers for the diagnosis of colon cancer. PMID:29928385

Neighborhood disadvantage as a moderator of the association between harsh parenting and toddler-aged children’s internalizing and externalizing problems

PubMed Central

Callahan, Kristin L.; Scaramella, Laura V.; Laird, Robert D.; Sohr-Preston, Sara L.

2011-01-01

Neighborhood dangerousness and belongingness were expected to moderate associations between harsh parenting and toddler-aged children’s problem behaviors. Fifty-five predominantly African American mothers participated with their 2-year old children. Neighborhood danger, neighborhood belongingness, and children’s problem behaviors were measured with mothers’ reports. Harsh parenting was measured with observer ratings. Analyses considered variance common to externalizing and internalizing problems, using a total problems score, and unique variance, by controlling for internalizing behavior when predicting externalizing behavior, and vice-versa. Regarding the common variance, only the main effects of neighborhood danger and harsh parenting were significantly associated with total problem behavior. In contrast, after controlling for externalizing problems, the positive association between harsh parenting and unique variance in internalizing problems became stronger as neighborhood danger increased. No statistically significant associations emerged for the models predicting the unique variance in externalizing problems or models considering neighborhood belongingness. PMID:21355648

Neighborhood disadvantage as a moderator of the association between harsh parenting and toddler-aged children's internalizing and externalizing problems.

PubMed

Callahan, Kristin L; Scaramella, Laura V; Laird, Robert D; Sohr-Preston, Sara L

2011-02-01

Neighborhood dangerousness and belongingness were expected to moderate associations between harsh parenting and toddler-age children's problem behaviors. Fifty-five predominantly African American mothers participated with their 2-year old children. Neighborhood danger, neighborhood belongingness, and children's problem behaviors were measured with mothers' reports. Harsh parenting was measured with observer ratings. Analyses considered variance common to externalizing and internalizing problems, using a total problems score, and unique variance, by controlling for internalizing behavior when predicting externalizing behavior, and vice versa. Regarding the common variance, only the main effects of neighborhood danger and harsh parenting were significantly associated with total problem behavior. In contrast, after controlling for externalizing problems, the positive association between harsh parenting and unique variance in internalizing problems became stronger as neighborhood danger increased. No statistically significant associations emerged for the models predicting the unique variance in externalizing problems or models considering neighborhood belongingness. PsycINFO Database Record (c) 2011 APA, all rights reserved.

Nurse teacher stress in Northern Ireland.

PubMed

Hunter, P; Houghton, D M

1993-08-01

Occupational stress among a 60% sample of all nurse tutors in Northern Ireland was investigated by means of the General Health Questionnaire (GHQ), Maslach Burnout Inventory and a stress questionnaire. Seventy per cent of tutors judged themselves to be worse or much worse than usual on 45% of GHQ items. Significant levels of moderate and high burnout were discovered on the sub-scales of emotional exhaustion and depersonalization, with an almost unanimous (95%) report of high burnout arising out of feelings of lack of personal accomplishment. Male nurse tutors reported more frequent and more intense signs of burnout than their female counterparts at a statistically significant level of difference in emotional exhaustion (P = 0.028 and P = 0.003 respectively) and in depersonalization (P < 0.003 and P = 0.007 respectively). The work stressor most commonly identified by tutors (72%) was that of experiencing too little time to perform their duties to their satisfaction. The most common request for help to alleviate workplace stress (61%) was for more support and appreciation from their seniors.

iStent trabecular micro-bypass stent for open-angle glaucoma

PubMed Central

Le, Kim; Saheb, Hady

2014-01-01

Trabecular micro-bypass stents, commonly known as iStents, are micro-invasive glaucoma surgery (MIGS) devices used to treat open-angle glaucoma. Like other MIGS procedures that enhance trabecular outflow, the iStent lowers intraocular pressure (IOP) by creating a direct channel between the anterior chamber and Schlemm’s canal. iStents are typically implanted at the time of phacoemulsification for patients with open-angle glaucoma and visually significant cataracts. This review summarizes the published data regarding the efficacy, safety, and cost considerations of trabecular micro-bypass stents. Most studies found statistically significant reductions in mean IOP and ocular medication use after combined phacoemulsification with single or double iStent implantation. The devices were found to be very safe, with a safety profile similar to that of cataract surgery. Complications were infrequent, with the most common complications being temporary stent obstruction or malposition, which resolved with observation or secondary procedures. Future studies are needed to evaluate long-term outcomes, patient satisfaction, cost effectiveness, and expanded indications. PMID:25284980

Immunohistochemical evaluation of inducible nitric oxide synthase in the epithelial lining of odontogenic cysts: A qualitative and quantitative analysis

PubMed Central

Akshatha, B K; Karuppiah, Karpagaselvi; Manjunath, G S; Kumarswamy, Jayalakshmi; Papaiah, Lokesh; Rao, Jyothi

2017-01-01

Introduction: The three common odontogenic cysts include radicular cysts (RCs), dentigerous cysts (DCs), and odontogenic keratocysts (OKCs). Among these 3 cysts, OKC is recently been classified as benign keratocystic odontogenic tumor attributing to its aggressive behavior, recurrence rate, and malignant potential. The present study involved qualitative and quantitative analysis of inducible nitric oxide synthase (iNOS) expression in epithelial lining of RCs, DCs, and OKCs, compare iNOS expression in epithelial linings of all the 3 cysts and determined overexpression of iNOS in OKCs which might contribute to its aggressive behavior and malignant potential. Aims: The present study is to investigate the role of iNOS in the pathogenesis of OKCs, DCs, and RCs by evaluating the iNOS expression in the epithelial lining of these cysts. Subjects and Methods: Analysis of iNOS expression in epithelial lining cells of 20 RCs, 20 DCs, and 20 OKCs using immunohistochemistry done. Statistical Analysis Used: The percentage of positive cells and intensity of stain was assessed and compared among all the 3 cysts using contingency coefficient. Kappa statistics for the two observers were computed for finding interobserver agreement. Results: The percentage of iNOS-positive cells was found to be remarkably high in OKCs (12/20) –57.1% as compared to RCs (6/20) – 28.6% and DCs (3/20) – 14.3%. The interobserver agreement for iNOS-positive percentage cells was arrived with kappa values with OKCs → Statistically significant (P > 0.000), RCs → statistically significant (P > 0.001) with no significant values for DCs. No statistical difference exists among 3 study samples in regard to the intensity of staining with iNOS. Conclusions: Increased iNOS expression in OKCs may contribute to bone resorption and accumulation of wild-type p53, hence, making OKCs more aggressive. PMID:29391711

Incidence and variance of knee injuries in elite college football players.

PubMed

Bradley, James; Honkamp, Nicholas J; Jost, Patrick; West, Robin; Norwig, John; Kaplan, Lee D

2008-06-01

Knee injuries are among the most common musculoskeletal injuries in US football players. The literature includes little information about the role of player position and risk for knee injury. We hypothesized that the incidence of knee injury in elite collegiate US football players is high and that type of injury varies by player position. We evaluated 332 elite collegiate US football players at the 2005 National Football League Combine. All players underwent radiographic examinations, including plain x-rays and/or magnetic resonance imaging when necessary. All knee pathologic conditions and surgical procedures were recorded. Data were analyzed by player position to detect any trends. Fifty-four percent (179) of the 332 players had a history of knee injury; knee injuries totaled 233 (1.3/player injured). Eighty-six players (25.9%) had a total of 114 surgeries. The most common injuries were medial collateral ligament injury (n = 79), meniscal injury (n = 51), and anterior cruciate ligament (ACL) injury (n = 40). The most common surgeries were arthroscopic meniscectomy (n = 39), ACL reconstruction (n = 35), and arthroscopic meniscal repair (n = 13). A history of knee injury was most common in defensive linemen (68% of players), tight ends (57%), and offensive linemen (57%). Knee surgery was more commonly performed on running backs (36%) and linebackers (34%). There were no significant associations between type or frequency of specific injuries with regard to player position. Knee injuries are common injuries in elite collegiate football players, and one fourth of these players undergo surgical procedures. However, there were no statistically significant differences in type or frequency of injuries by player position.

Prevalence of Giardia duodenalis and Cryptosporidium species infections among children and cattle in North Shewa Zone, Ethiopia.

PubMed

Wegayehu, Teklu; Adamu, Haileeyesus; Petros, Beyene

2013-09-08

Giardia and Cryptosporidium are the most common causes of protozoan diarrhea that lead to significant morbidity and mortality worldwide. The purpose of this study was to determine the prevalence of Giardia duodenalis and Cryptosporidium species infections among children and cattle, and to assess the potential risk of zoonotic transmission. This cross-sectional study was conducted between January and April 2009 in Girar Jarso and Dera Districts of North Shewa Zone, Oromia Region, Ethiopia. A total of 768 stool specimens were collected and examined for intestinal parasites using direct wet mount with saline and formalin ether concentration methods. The modified Ziehl-Neelsen staining method was used for the detection of Cryptosporidium species. Statistical analysis was performed using SPSS software version 15. Out of 384 children examined, 53 (13.8%) and 28 (7.3%) were positive for Giardia and Cryptosporidium infections, respectively. Similarly, of the total 384 cattle examined, 9 (2.3%) were positive for Giardia duodenalis and 30 (7.8%) were positive for Cryptosporidium infection. The prevalence of giardiasis was significantly higher among children who had close contact with cattle 33 (18.7%) compared to children who had no contact with cattle 20 (9.6%) (P < 0.05). Higher number of Cryptosporidium infection was also recorded in children who had close contact with cattle 15 (8.5%). Difference in prevalence of giardiasis and cryptosporidiosis among children was not statistically significant between males and females. On the other hand, difference in the prevalence of giardiasis among children was statistically significant between age groups. Higher prevalence of Giardia duodenalis infection detected among children was significantly associated with contact with cattle and manure that the children had. Further analysis using molecular techniques is needed to explain the existence of zoonotic transmission in the study area.

Topical isotretinoin for melasma in Thai patients: a vehicle-controlled clinical trial.

PubMed

Leenutaphong, V; Nettakul, A; Rattanasuwon, P

1999-09-01

Melasma is an acquired hyperpigmentary disorder commonly seen in Orientals. Recently it has been demonstrated that tretinoin (all-trans-retinoic acid) can produce significant clinical improvement of melasma. However, moderate cutaneous side effects (retinoid dermatitis) occurred in a number of patients. To investigate the efficacy of topical 0.05 per cent isotretinoin gel (Isotrex) in the treatment of melasma in Thai patients. Thirty patients with moderate to severe melasma entered a 40-week, randomized, vehicle-controlled clinical trial in which they applied either 0.05 per cent isotretinoin gel, or its vehicle base together with a broad spectrum sunscreen (SPF 28) daily to the entire face. They were evaluated clinically (using Melasma Area and Severity Index), and colorimetrically (using our Melasma Area and Melanin Index). After 40 weeks, the average MASI and MAMI scores of the isotretinoin-treated group decreased by 68.2 per cent and 47 per cent respectively, while the corresponding control scores declined 60 per cent and 34 per cent. There was no statistically significant difference between the isotretinoin and vehicle groups. When the MASI and MAMI scores of each visit were compared to their baseline data, a statistically significant reduction of the score was first noted at weeks 4 and 12 respectively. Lightening of melasma, as determined clinically (MASI score), correlated well with pigmentation measurements (MAMI score). Side effects were limited to a mild transient "retinoid dermatitis" occurring in 27 per cent of isotretinoin-treated patients. Daily use of broad spectrum sunscreen has a significant lightening effect on melasma in Thai patients. However, there was no statistically significant difference between the isotretinoin and vehicle-treated group.

Polymorphism of the PAI-1gene (4G/5G) may be linked with Polycystic Ovary Syndrome and associated pregnancy disorders in South Indian Women

PubMed Central

Mary, Maniraja Jesintha; Saravanan, Lakshmanan; Deecaraman, Munuswamy; Vijayalakshmi, Melantharu; Umashankar, Vetrivel; Sailaja, Jaigopal

2017-01-01

Polycystic Ovary syndrome (PCOS) is the most common endocrine disorder affecting 5 - 10% of all women of reproductive age group. The present research was carried out to study the impact of Plasminogen Activator Inhibitor (PAI-1) 4G/5G polymorphism (rs1799889) in PCOS, and the risk of developing PCOS in South Indian Population. The study was carried out in 60 subjects of South Indian population (30 PCOS and 30 Non PCOS) recruited from ARC Research and Fertility Centre, Chennai, India. Genotype and Allelic frequencies were compared by Fisher exact test, Hardy Weinberg equilibrium. p<0.05 was considered statistically significant. The Genotype frequency difference between PCOS and non-PCOS was observed as statistically non-significant (p=0.4647, OR=1.3077, 95% CI 0.63-2.68). The allelic frequency distribution in Spontaneous Abortion (SAB) cases in total subjects is not found to be statistically significant (p=0. 29), however the PCOS women carrying mutant homozygous and heterozygous genotype are more prone to recurrent pregnancy loss. Out of 17 Implantation failure cases, 23.52% were found to carry mutant homozygous (4G/4G), and 66.66% carried mutant heterozygous (4G/5G), and 5.88% carried wild type homozygous (5G/5G), the allelic difference was highly significant with 4G (62.5%), and 5G (37.5%). P value is highly significant and recorded at p=0.0164. The positive correlation between PAI-1 4G/5G polymorphism and PCOS risk was not observed in this study, however, the correlation between Recurrent Pregnancy Loss (RPL) and Implantation failures were observed in PCOS cases. PMID:28690381

Polymorphism of the PAI-1gene (4G/5G) may be linked with Polycystic Ovary Syndrome and associated pregnancy disorders in South Indian Women.

PubMed

Mary, Maniraja Jesintha; Saravanan, Lakshmanan; Deecaraman, Munuswamy; Vijayalakshmi, Melantharu; Umashankar, Vetrivel; Sailaja, Jaigopal

2017-01-01

Polycystic Ovary syndrome (PCOS) is the most common endocrine disorder affecting 5 - 10% of all women of reproductive age group. The present research was carried out to study the impact of Plasminogen Activator Inhibitor (PAI-1) 4G/5G polymorphism (rs1799889) in PCOS, and the risk of developing PCOS in South Indian Population. The study was carried out in 60 subjects of South Indian population (30 PCOS and 30 Non PCOS) recruited from ARC Research and Fertility Centre, Chennai, India. Genotype and Allelic frequencies were compared by Fisher exact test, Hardy Weinberg equilibrium. p<0.05 was considered statistically significant. The Genotype frequency difference between PCOS and non-PCOS was observed as statistically non-significant (p=0.4647, OR=1.3077, 95% CI 0.63-2.68). The allelic frequency distribution in Spontaneous Abortion (SAB) cases in total subjects is not found to be statistically significant (p=0. 29), however the PCOS women carrying mutant homozygous and heterozygous genotype are more prone to recurrent pregnancy loss. Out of 17 Implantation failure cases, 23.52% were found to carry mutant homozygous (4G/4G), and 66.66% carried mutant heterozygous (4G/5G), and 5.88% carried wild type homozygous (5G/5G), the allelic difference was highly significant with 4G (62.5%), and 5G (37.5%). P value is highly significant and recorded at p=0.0164. The positive correlation between PAI-1 4G/5G polymorphism and PCOS risk was not observed in this study, however, the correlation between Recurrent Pregnancy Loss (RPL) and Implantation failures were observed in PCOS cases.

Evaluation of hyperglycaemic response to intra-operative dexamethasone administration in patients undergoing elective intracranial surgery: A randomised, prospective study.

PubMed

Sethi, Rakesh; Naqash, Imtiaz A; Bajwa, Sukhminder Jit Singh; Dutta, Vikas; Ramzan, Altaf Umar; Zahoor, Syed Amir

2016-01-01

The glucocorticoid dexamethasone in a bolus dose of 8-10 mg followed by quarterly dose of 4 mg is commonly used during intracranial surgery so as to reduce oedema and vascular permeability. However, the detrimental hyperglycaemic effects of dexamethasone may override its potentially beneficial effects. The present prospective, randomised study aimed at comparing the degree and magnitude of hyperglycaemia induced by prophylactic administration of dexamethasone in patients undergoing elective craniotomy. Sixty American Society of Anaesthesiologist (ASA) grade-I and II patients were randomly assigned to three groups of 20 patients each. Group-I received dexamethasone during surgery for the first time. Group-II received dexamethasone in addition to receiving it pre-operatively, whereas Group-III (control group) patients were administered normal saline as placebo. Baseline blood glucose (BG) was measured in all the three groups before induction of anaesthesia and thereafter after every hour for 4 h and then two-hourly. Besides intra- and intergroup comparison of BG, peak BG concentration was also recorded for each patient. Statistical analysis was carried out with analysis of variance (ANOVA) and Student's t-test and value of P < 0.05 was considered statistically significant. Baseline BG reading were higher and statistically significant in Group-II as compared with Group-I and Group-III (P < 0.05). However, peak BG levels were significantly higher in Group-I than in Group-II and III (P < 0.05). Similarly, the magnitude of change in peak BG was significantly higher in Group-I as compared to Group-II and III (P < 0.05). Peri-operative administration of dexamethasone during neurosurgical procedures can cause significant increase in BG concentration especially in patients who receive dexamethasone intra-operatively only.

Evaluation of hyperglycaemic response to intra-operative dexamethasone administration in patients undergoing elective intracranial surgery: A randomised, prospective study

PubMed Central

Sethi, Rakesh; Naqash, Imtiaz A.; Bajwa, Sukhminder Jit Singh; Dutta, Vikas; Ramzan, Altaf Umar; Zahoor, Syed Amir

2016-01-01

Background and Aim: The glucocorticoid dexamethasone in a bolus dose of 8-10 mg followed by quarterly dose of 4 mg is commonly used during intracranial surgery so as to reduce oedema and vascular permeability. However, the detrimental hyperglycaemic effects of dexamethasone may override its potentially beneficial effects. The present prospective, randomised study aimed at comparing the degree and magnitude of hyperglycaemia induced by prophylactic administration of dexamethasone in patients undergoing elective craniotomy. Materials and Methods: Sixty American Society of Anaesthesiologist (ASA) grade-I and II patients were randomly assigned to three groups of 20 patients each. Group-I received dexamethasone during surgery for the first time. Group-II received dexamethasone in addition to receiving it pre-operatively, whereas Group-III (control group) patients were administered normal saline as placebo. Baseline blood glucose (BG) was measured in all the three groups before induction of anaesthesia and thereafter after every hour for 4 h and then two-hourly. Besides intra- and intergroup comparison of BG, peak BG concentration was also recorded for each patient. Statistical analysis was carried out with analysis of variance (ANOVA) and Student's t-test and value of P < 0.05 was considered statistically significant. Results: Baseline BG reading were higher and statistically significant in Group-II as compared with Group-I and Group-III (P < 0.05). However, peak BG levels were significantly higher in Group-I than in Group-II and III (P < 0.05). Similarly, the magnitude of change in peak BG was significantly higher in Group-I as compared to Group-II and III (P < 0.05). Conclusion: Peri-operative administration of dexamethasone during neurosurgical procedures can cause significant increase in BG concentration especially in patients who receive dexamethasone intra-operatively only. PMID:27057213

Comparative study between: Carboxytherapy, platelet-rich plasma, and tripolar radiofrequency, their efficacy and tolerability in striae distensae.

PubMed

Ahmed, Naglaa A; Mostafa, Osama M

2018-06-19

Striae distensae are very common cutaneous disorders that produce great psychological stress for women. measure and compare between efficacy and tolerability of three modalities for treatment of striae distensae. Forty-five female patients with striae distensae were randomly selected from the outpatient dermatology clinics of Al-Zahra university Hospital within 6 months period. Patients divided into three groups according to the therapeutic modalities were used. Group A: treated with carboxytherapy using carbon dioxide (CO2) injection, Group B: where patients were treated with intradermal injection of autologous platelet-rich plasma (PRP), and Group C: where we used tripolar radiofrequency (RF) for treatment. All treated groups showed overall clinical improvement as regards the width, texture, and overall improvement after treatment (P > .05), with no statistically significant differences between the three groups. Patient's satisfaction was statistically significantly better in both group C (93.33%) and group A (80%) while group B (53.33%) was less with minimal side effects such as pain and ecchymosis, which were more frequent in group B than the other two groups; but with no statistically significance differences both groups A and C were effective with no significant differences in both types of striae and in any site of the body but group B is significantly more effective on striae rubra on trunk, with better improvement of lesions texture. The three modalities of treatments proved to be effective clinically and histopathologically in treating both types of striae, which were well tolerated by the patients with minimal, transient side effects and our study results gave us guidelines for their clinical application. © 2018 Wiley Periodicals, Inc.

Practices participating in a dental PBRN have substantial and advantageous diversity even though as a group they have much in common with dentists at large

PubMed Central

Makhija, Sonia K; Gilbert, Gregg H; Rindal, D Brad; Benjamin, Paul; Richman, Joshua S; Pihlstrom, Daniel J; Qvist, Vibeke

2009-01-01

Background Practice-based research networks offer important opportunities to move recent advances into routine clinical practice. If their findings are not only generalizable to dental practices at large, but can also elucidate how practice characteristics are related to treatment outcome, their importance is even further elevated. Our objective was to determine whether we met a key objective for The Dental Practice-Based Research Network (DPBRN): to recruit a diverse range of practitioner-investigators interested in doing DPBRN studies. Methods DPBRN participants completed an enrollment questionnaire about their practices and themselves. To date, more than 1100 practitioners from the five participating regions have completed the questionnaire. The regions consist of: Alabama/Mississippi, Florida/Georgia, Minnesota, Permanente Dental Associates, and Scandinavia (Denmark, Norway, and Sweden). We tested the hypothesis that there are statistically significant differences in key characteristics among DPBRN practices, based on responses from dentists who participated in DPBRN's first network-wide study (n = 546). Results There were statistically significant, substantive regional differences among DPBRN-participating dentists, their practices, and their patient populations. Conclusion Although as a group, participants have much in common with practices at large; their substantial diversity offers important advantages, such as being able to evaluate how practice differences may affect treatment outcomes, while simultaneously offering generalizability to dentists at large. This should help foster knowledge transfer in both the research-to-practice and practice-to-research directions. PMID:19832991

Analysis of glutathione S-transferase Pi isoform (GSTP1) single-nucleotide polymorphisms and macular telangiectasia type 2.

PubMed

Szental, Joshua A; Baird, Paul N; Richardson, Andrea J; Islam, F M Amirul; Scholl, Hendrik P N; Charbel Issa, Peter; Holz, Frank G; Gillies, Mark; Guymer, Robyn H

2010-12-01

Recent imaging studies have suggested that macular pigment is decreased centrally in macular telangiectasia type 2 (MT2). The uptake of xanthophyll pigment into the macula is thought to be facilitated by a xanthophyll-binding protein (XBP). The Pi isoform of glutathione S-transferase (GSTP1) represents one such XBP with high binding affinity. This case-control study aimed to determine whether two common single-nucleotide polymorphisms (SNPs) of GSTP1 were associated with MT2. DNA samples from 39 cases and 21 controls were collected. Two polymorphic sites of Ile105Val and Ala114Val in exons 5 and 6 respectively, of the GSTP1 gene were analysed. Comparison of alleles and genotypes between cases and controls indicated that there were no statistically significant differences for either the Ile105Val SNP (P=0.43) or the Ala114Val SNP (P=0.85), or for any combinations; however, the homozygous at-risk genotype (GG) of the Ile105Val SNP was present in 8% of cases but absent in controls. This study found no statistically significant association between two common GSTP1 SNPs and MT2; however, a trend towards a greater frequency of the GG genotype of the Ile105Val SNP in cases is of great interest. The biological plausibility of disturbed macular pigment uptake in MT2 makes GSTP1 an excellent candidate gene. Further investigation is warranted in future studies of MT2.

Antibiotic prophylaxis patterns of Finnish dentists performing dental implant surgery.

PubMed

Pyysalo, Mikko; Helminen, Mika; Antalainen, Anna-Kaisa; Sándor, George K; Wolff, Jan

2014-11-01

The peri-operative use of prophylactic antibiotics in clinically healthy patients undergoing dental implant surgery is very common in Finland. While antibiotics are prescribed with the hope of preventing both local and systemic complications, their application and utilization is not uniform. The aim of this study was to assess the variation in prescribing patterns among Finnish dentists performing dental implant placement operations. This study also aimed to examine the possible relationship between early implant removal and the use of the prophylactic antibiotics in Finland. The National Institute for Health and Welfare in Finland granted permission to access the Finnish Dental Implant Register. The peri-operative antibiotic prophylaxis prescribing patterns were assessed in a total of 110 543 dental implant placement procedures and 1038 dental implant removal operations performed in Finland between April 1994 and April 2012. A total of 61 different antibiotics or combinations were prescribed peri-operatively during implant placements in Finland between 1994-2012. Phenoxymethylpenicillin was the most commonly prescribed drug (72.2%). No statistically significant difference in early implant removal rates could be found between patients who had or had not received peri-operative prophylaxis. However, patients who had received peri-operative prophylaxis had statistically significant longer implant survival rates. There is a variation in antibiotic prescribing patterns among Finnish dentists placing dental implants. The results suggest that the use of prophylactic antibiotics has little effect on the prevention of primary implant surgery-related complications and, hence, success rates.

Dermoscopy of accessory nipples in authors’ own study

PubMed Central

Szymszal, Jan; Silny, Wojciech

2014-01-01

Introduction The accessory nipple (AN) is characterised by its network-like structures, which may suggest the diagnosis of a melanocytic lesion. The knowledge about additional dermoscopic features of AN may greatly minimise the risk of unnecessary surgical excisions. Aim To analyse and present different clinical and dermoscopic forms, in which the AN may appear. Material and methods Ninety AN with dermoscopic features were evaluated in the study, detected in 14 patients between the years 2008 and 2014. Results The most common dermoscopic features of the AN were central, scar-like areas (15/19) and peripheral network-like structures (12/19). A number of cleft-like appearances (8/19) and central network-like structures (7/19) had also been observed. Moreover, among the dermoscopic features, white cobblestone-like structures (7/19), a central round dimpling with a plug (6/19) and fisheye-like structures resembling comedo-like openings (9/19) have all also been noted. There is a statistical significance in the occurrence of white cobblestone-like structures with central network-like structures (Fisher's exact test p = 0.0449). The presence of peripheral network-like structures with the occurrence of central scar-like areas was statistically highly significant (p = 0.0091). The central round dimpling was never observed alongside any central network-like structures in any of the lesions (p = 0.0436). Conclusions Accessory nipples are most commonly characterised by the occurrence of a peripheral network-like structure accompanied by the presence of a scar-like area. PMID:25097482

Comparison of survivability of Staphylococcus aureus and spores of Aspergillus niger on commonly used floor materials.

PubMed

Gupta, Mridula; Bisesi, Michael; Lee, Jiyoung

2017-07-01

The survivability of Staphylococcus aureus and spores of Aspergillus niger was compared on 5 common floor materials. Floor materials were inoculated with a known concentration of S aureus and spores of A niger on day 0. Their survivability was measured on days, 2, 7, 14, and 28 by bulk rinsate method and enumerated using culture-based method. The difference in change of S aureus levels was statistically significant for all tested days (P < .001) for all floor materials. Vinyl composition tile (VCT) and porcelain tile (PT) had statistically similar survivability and differed statistically from carpets. On both VCT and PT, positive growth for S aureus occurred by day 2 (1-1.7 log 10 ), declined slightly (0.1 to -0.2 log 10 ) by day 7, and remained positive until day 28. However, S aureus was undetected by day 7 on both carpets. A niger spores were undetected on residential broadloom carpet and rubber-backed commercial carpet after day 2 but survived on VCT, PT, and wood until day 28. Floor materials with hard and smooth surfaces, such as VCT and PT, can allow survival of S aureus and A niger for up to 4 weeks. It may imply that floor materials can play a major role in preserving microbial contaminants in the built environment. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

[Drug use and sexual practices of teenagers in the city of Medellin (Colombia)].

PubMed

Castaño Pérez, Guillermo A; Arango Tobon, Eduardo; Morales Mesa, Santiago; Rodríguez Bustamante, Alexander; Montoya Montoya, Carolina

2012-01-01

The purpose of this research project was to study the relationship between drug consumption and sexual practices in teenagers in the city of Medellin, Colombia. A transversal studied was designed in order to identify the variables related to having had sexual intercourse under the effects of drugs or alcohol. The sample was made up of 955 teenagers between 14 and 17, who were in 9th, 10th and 11th grades in public and private schools in the city of Medellin. The results show that the prevalence of drug and alcohol influence in sexual intercourse is 43,67%. The most common drugs used for sexual practices are alcohol, marihuana, popper, cocaine and ecstasy. Consuming alcohol or drugs and having sexual practices shows an associated meaningful statistic (p= .001). The more common sexual practices under psychoactive substances are the exploratory ones (caresses and touching) (71%), vaginal penetration (63.67%), oral sex (45.30%) and masturbation (19.59%). Regarding the protection methods during sexual intercourse under drug or alcohol influence 55,9% always use a condom, 37,3% sometimes use it, and 6,8% never do it. This study proves what had been previously established by other research projects that show a high statistic association between drug consumption and sexual practices, but realizes that there is no statistically significant association between sexual practices under the influence of alcohol or drugs and the use or non-use of protective methods, which is the most important finding.

Antecedents to Organizational Performance: Theoretical and Practical Implications for Aircraft Maintenance Officer Force Development

DTIC Science & Technology

2015-03-26

to my reader, Lieutenant Colonel Robert Overstreet, for helping solidify my research, coaching me through the statistical analysis, and positive...61  Descriptive Statistics .............................................................................................................. 61...common-method bias requires careful assessment of potential sources of bias and implementing procedural and statistical control methods. Podsakoff

The Empirical Nature and Statistical Treatment of Missing Data

ERIC Educational Resources Information Center

Tannenbaum, Christyn E.

2009-01-01

Introduction. Missing data is a common problem in research and can produce severely misleading analyses, including biased estimates of statistical parameters, and erroneous conclusions. In its 1999 report, the APA Task Force on Statistical Inference encouraged authors to report complications such as missing data and discouraged the use of…

The Importance of Attitudes in Statistics Education

ERIC Educational Resources Information Center

Ramirez, Caroline; Schau, Candace; Emmioglu, Esma

2012-01-01

People forget what they do not use. But attitudes "stick." Our article emphasizes the importance of students' attitudes toward statistics. We examine 15 surveys that purport to assess these attitudes and then describe the "Survey of Attitudes Toward Statistics," a commonly used attitude survey. We present our conceptual model…

The Impact of Student-Directed Projects in Introductory Statistics

ERIC Educational Resources Information Center

Spence, Dianna J.; Bailey, Brad; Sharp, Julia L.

2017-01-01

A multi-year study investigated the impact of incorporating student-directed discovery projects into introductory statistics courses. Pilot instructors at institutions across the United States taught statistics implementing student-directed projects with the help of a common set of instructional materials designed to facilitate such projects.…

TinkerPlots™ Model Construction Approaches for Comparing Two Groups: Student Perspectives

ERIC Educational Resources Information Center

Noll, Jennifer; Kirin, Dana

2017-01-01

Teaching introductory statistics using curricula focused on modeling and simulation is becoming increasingly common in introductory statistics courses and touted as a more beneficial approach for fostering students' statistical thinking. Yet, surprisingly little research has been conducted to study the impact of modeling and simulation curricula…

A Pilot Study Teaching Metrology in an Introductory Statistics Course

ERIC Educational Resources Information Center

Casleton, Emily; Beyler, Amy; Genschel, Ulrike; Wilson, Alyson

2014-01-01

Undergraduate students who have just completed an introductory statistics course often lack deep understanding of variability and enthusiasm for the field of statistics. This paper argues that by introducing the commonly underemphasized concept of measurement error, students will have a better chance of attaining both. We further present lecture…

Understanding the Sampling Distribution and the Central Limit Theorem.

ERIC Educational Resources Information Center

Lewis, Charla P.

The sampling distribution is a common source of misuse and misunderstanding in the study of statistics. The sampling distribution, underlying distribution, and the Central Limit Theorem are all interconnected in defining and explaining the proper use of the sampling distribution of various statistics. The sampling distribution of a statistic is…

The Role of the Sampling Distribution in Understanding Statistical Inference

ERIC Educational Resources Information Center

Lipson, Kay

2003-01-01

Many statistics educators believe that few students develop the level of conceptual understanding essential for them to apply correctly the statistical techniques at their disposal and to interpret their outcomes appropriately. It is also commonly believed that the sampling distribution plays an important role in developing this understanding.…

The Development of a Professional Statistics Teaching Identity

ERIC Educational Resources Information Center

Whitaker, Douglas

2016-01-01

Motivated by the increased statistics expectations for students and their teachers because of the widespread adoption of the Common Core State Standards for Mathematics, this study explores exemplary, in-service statistics teachers' professional identities using a theoretical framework informed by Gee (2000) and communities of practice (Lave &…

A spatial scan statistic for multiple clusters.

PubMed

Li, Xiao-Zhou; Wang, Jin-Feng; Yang, Wei-Zhong; Li, Zhong-Jie; Lai, Sheng-Jie

2011-10-01

Spatial scan statistics are commonly used for geographical disease surveillance and cluster detection. While there are multiple clusters coexisting in the study area, they become difficult to detect because of clusters' shadowing effect to each other. The recently proposed sequential method showed its better power for detecting the second weaker cluster, but did not improve the ability of detecting the first stronger cluster which is more important than the second one. We propose a new extension of the spatial scan statistic which could be used to detect multiple clusters. Through constructing two or more clusters in the alternative hypothesis, our proposed method accounts for other coexisting clusters in the detecting and evaluating process. The performance of the proposed method is compared to the sequential method through an intensive simulation study, in which our proposed method shows better power in terms of both rejecting the null hypothesis and accurately detecting the coexisting clusters. In the real study of hand-foot-mouth disease data in Pingdu city, a true cluster town is successfully detected by our proposed method, which cannot be evaluated to be statistically significant by the standard method due to another cluster's shadowing effect. Copyright © 2011 Elsevier Inc. All rights reserved.

Quantification of uncertainty in the prediction of railway induced ground vibration due to the use of statistical track unevenness data

NASA Astrophysics Data System (ADS)

Lombaert, G.; Galvín, P.; François, S.; Degrande, G.

2014-09-01

Environmental vibrations due to railway traffic are predominantly due to dynamic axle loads caused by wheel and track unevenness and impact excitation by rail joints and wheel flats. Because of its irregular character, track unevenness is commonly processed statistically and represented by its power spectral density function or its root mean square (RMS) value in one-third octave bands. This statistical description does not uniquely define the track unevenness at a given site, however, and different track unevenness profiles matching the statistical description will lead to different predictions of dynamic axle loads and resulting ground vibration. This paper presents a methodology that allows quantifying the corresponding variability in ground vibration predictions. The procedure is derived assuming the geometry of the track and soil to be homogeneous along the track. The procedure is verified by means of Monte Carlo simulations and its usefulness for assessing the mismatch between predicted and measured ground vibrations is demonstrated in a case study. The results show that the response in time domain and its narrow band spectrum exhibit significant variability which is reduced when the running RMS value or the one-third octave band spectrum of the response is considered.

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

Hagos, Samson M.; Feng, Zhe; Burleyson, Casey D.

Regional cloud permitting model simulations of cloud populations observed during the 2011 ARM Madden Julian Oscillation Investigation Experiment/ Dynamics of Madden-Julian Experiment (AMIE/DYNAMO) field campaign are evaluated against radar and ship-based measurements. Sensitivity of model simulated surface rain rate statistics to parameters and parameterization of hydrometeor sizes in five commonly used WRF microphysics schemes are examined. It is shown that at 2 km grid spacing, the model generally overestimates rain rate from large and deep convective cores. Sensitivity runs involving variation of parameters that affect rain drop or ice particle size distribution (more aggressive break-up process etc) generally reduce themore » bias in rain-rate and boundary layer temperature statistics as the smaller particles become more vulnerable to evaporation. Furthermore significant improvement in the convective rain-rate statistics is observed when the horizontal grid-spacing is reduced to 1 km and 0.5 km, while it is worsened when run at 4 km grid spacing as increased turbulence enhances evaporation. The results suggest modulation of evaporation processes, through parameterization of turbulent mixing and break-up of hydrometeors may provide a potential avenue for correcting cloud statistics and associated boundary layer temperature biases in regional and global cloud permitting model simulations.« less

Predicting recreational water quality advisories: A comparison of statistical methods

USGS Publications Warehouse

Brooks, Wesley R.; Corsi, Steven R.; Fienen, Michael N.; Carvin, Rebecca B.

2016-01-01

Epidemiological studies indicate that fecal indicator bacteria (FIB) in beach water are associated with illnesses among people having contact with the water. In order to mitigate public health impacts, many beaches are posted with an advisory when the concentration of FIB exceeds a beach action value. The most commonly used method of measuring FIB concentration takes 18–24 h before returning a result. In order to avoid the 24 h lag, it has become common to ”nowcast” the FIB concentration using statistical regressions on environmental surrogate variables. Most commonly, nowcast models are estimated using ordinary least squares regression, but other regression methods from the statistical and machine learning literature are sometimes used. This study compares 14 regression methods across 7 Wisconsin beaches to identify which consistently produces the most accurate predictions. A random forest model is identified as the most accurate, followed by multiple regression fit using the adaptive LASSO.

Relationship between increased carotid artery stiffness and idiopathic subjective tinnitus.

PubMed

Bayraktar, C; Taşolar, S

2017-05-01

Tinnitus is defined as perception of sound with no external stimulus, and can separate into pulsatile and non-pulsatile types. Arterial stiffness is a parameter that can predict the cardiovascular event and associated with incidence of stroke. It has been shown that increased arterial stiffness may lead to microvascular damage in brain. Our aim was to assess the arterial stiffness of the carotid system in the development and severity of idiopathic subjective tinnitus. Forty subjective tinnitus patients and 40 age- and sex-matched controls were enrolled in the study. The parameters obtained from the participants included pure tone hearing (dB), serum lipid profile (mg/dl), fasting glucose (mg/dl), blood pressure (mmHg), and body mass index (BMI, kg/m 2 ). The common carotid artery (CCA) stiffness index, Young's elastic modulus (YEM), common carotid intima-media thickness (CIMT), peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index (RI), pulsatility index (PI), vessel diameter, mean velocity (MV), and volume flow (VF) were measured in both the right and left common carotid arteries in both groups. The CCA stiffness index, YEM measurements, right CIMT, and left PI were found to be significantly higher in the patients than those in the control group (p < 0.05). With regard to the severity of the tinnitus and the patient characteristics, there was a significant positive correlation with the CCA stiffness index, YEM measurements, left CIMT, and neutrophil-to-lymphocyte ratio (NLR). However, only the right and left CCA stiffness parameters were found to be statistically significant in the multivariate analysis as independent predictors of a moderate to high degree of tinnitus. The increased stiffness index of the common carotid arteries was significantly associated with the formation and severity of tinnitus. Therefore, an assessment of the carotideal system may be helpful in these patients.

Variability in common synaptic input to motor neurons modulates both force steadiness and pegboard time in young and older adults.

PubMed

Feeney, Daniel F; Mani, Diba; Enoka, Roger M

2018-06-07

We investigated the associations between grooved pegboard times, force steadiness (coefficient of variation for force), and variability in an estimate of the common synaptic input to motor neurons innervating the wrist extensor muscles during steady contractions performed by young and older adults. The discharge times of motor units were derived from recordings obtained with high-density surface electrodes while participants performed steady isometric contractions at 10% and 20% of maximal voluntary contraction (MVC) force. The steady contractions were performed with a pinch grip and wrist extension, both independently (single action) and concurrently (double action). The variance in common synaptic input to motor neurons was estimated with a state-space model of the latent common input dynamics. There was a statistically significant association between the coefficient of variation for force during the steady contractions and the estimated variance in common synaptic input in young (r 2 = 0.31) and older (r 2 = 0.39) adults, but not between either the mean or the coefficient of variation for interspike interval of single motor units with the coefficient of variation for force. Moreover, the estimated variance in common synaptic input during the double-action task with the wrist extensors at the 20% target was significantly associated with grooved pegboard time (r 2 = 0.47) for older adults, but not young adults. These findings indicate that longer pegboard times of older adults were associated with worse force steadiness and greater fluctuations in the estimated common synaptic input to motor neurons during steady contractions. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Symptoms of Common Mental Disorders and Adverse Health Behaviours in Male Professional Soccer Players

PubMed Central

Gouttebarge, Vincent; Aoki, Haruhito; Kerkhoffs, Gino

2015-01-01

To present time, scientific knowledge about symptoms of common mental disorders and adverse health behaviours among professional soccer players is lacking. Consequently, the aim of the study was to determine the prevalence of symptoms of common mental disorders (distress, anxiety/depression, sleep disturbance) and adverse health behaviours (adverse alcohol behaviour, smoking, adverse nutrition behaviour) among professional soccer players, and to explore their associations with potential stressors (severe injury, surgery, life events and career dissatisfaction). Cross-sectional analyses were conducted on baseline questionnaires from an ongoing prospective cohort study among male professional players. Using validated questionnaires to assess symptoms of common mental disorders and adverse health behaviours as well as stressors, an electronic questionnaire was set up and distributed by players’ unions in 11 countries from three continents. Prevalence of symptoms of common mental disorders and adverse health behaviours among professional soccer players ranged from 4% for smoking and 9% for adverse alcohol behaviour to 38% for anxiety/depression and 58% for adverse nutrition behaviour. Significant associations were found for a higher number of severe injuries with distress, anxiety/depression, sleeping disturbance and adverse alcohol behaviour, an increased number of life events with distress, sleeping disturbance, adverse alcohol behaviour and smoking, as well as an elevated level of career dissatisfaction with distress, anxiety/depression and adverse nutrition behaviour. Statistically significant correlations (p<0.01) were found for severe injuries and career dissatisfaction with most symptoms of common mental disorders. High prevalence of symptoms of common mental disorders and adverse health behaviours was found among professional players, confirming a previous pilot-study in a similar study population. PMID:26925182

The prevalence of Pediculus humanus capitis and the coexistence of intestinal parasites in young children in boarding schools in Sivas, Turkey.

PubMed

Değerli, Serpil; Malatyali, Erdoğan; Çeliksöz, Ali; Özçelik, Semra; Mumcuoğlu, Kosta Y

2012-01-01

The aim of this study was to investigate the prevalence of Pediculus humanus capitis and the coexistence of intestinal parasites in boarding primary schools in Sivas, Turkey. Seven hundred seventy-two students (350 [45.3%] girls, 422 [54.7%] boys) were evaluated with combing for the presence of head lice, collection of fecal samples, and examination of the perianal region for intestinal parasites using the cellophane tape method. The overall infestation rate for head lice was 6% (n=46). Nine children had evidence of nits only (1.2%), whereas living lice and nits or eggs were found in 37 children (4.8%). Girls were significantly more commonly infested (12.9%) than boys (0.2%). Of the parameters evaluated, socioeconomic level, number of rooms per family, and size and weight of the children were statistically significantly different between the children with and without lice. Although the infestation rate of children with intestinal parasites was higher in the head louse-infested group (23.9%) than in the group of children without lice (17.6%), the differences were not statistically significant. © 2011 Wiley Periodicals, Inc.

Statistically validated network of portfolio overlaps and systemic risk.

PubMed

Gualdi, Stanislao; Cimini, Giulio; Primicerio, Kevin; Di Clemente, Riccardo; Challet, Damien

2016-12-21

Common asset holding by financial institutions (portfolio overlap) is nowadays regarded as an important channel for financial contagion with the potential to trigger fire sales and severe losses at the systemic level. We propose a method to assess the statistical significance of the overlap between heterogeneously diversified portfolios, which we use to build a validated network of financial institutions where links indicate potential contagion channels. The method is implemented on a historical database of institutional holdings ranging from 1999 to the end of 2013, but can be applied to any bipartite network. We find that the proportion of validated links (i.e. of significant overlaps) increased steadily before the 2007-2008 financial crisis and reached a maximum when the crisis occurred. We argue that the nature of this measure implies that systemic risk from fire sales liquidation was maximal at that time. After a sharp drop in 2008, systemic risk resumed its growth in 2009, with a notable acceleration in 2013. We finally show that market trends tend to be amplified in the portfolios identified by the algorithm, such that it is possible to have an informative signal about institutions that are about to suffer (enjoy) the most significant losses (gains).

Oral health literacy: awareness and practices among pediatric dentists.

PubMed

Stowers, Megan E; Lee, Jessica Y; Majewski, Robert F; Estrella, Maria Regina P; Taylor, George W; Boynton, James R

2013-01-01

The purpose of this study was to examine pediatric dentists' awareness and experiences with oral health literacy and to identify communication techniques used with parents. Active North American members of the American Academy of Pediatric Dentistry were invited to participate in the survey. Descriptive statistical analyses were completed, and Pearson's chi-square crosstabs tests were used to compare categorical data between groups. Data were collected from 22 percent (N=1,059) of pediatric dentists; 68 to 87 percent use basic communication techniques routinely, while 36 to 79 percent routinely use enhanced communication techniques. Approximately 59 percent (N=620) reported having had an experience with health literacy miscommunication, while 11 percent (N=116) are aware of an error in patient care that resulted from oral health literacy miscommunication. Respondents who have had an experience with miscommunication were significantly more likely statistically to perceive barriers to effective communication as more significant than those without a history of miscommunication experience (P<.001). Most pediatric dentists have experienced situations in which a parent has misunderstood information. Basic communication techniques were most commonly used, while enhanced communication techniques were used less routinely. Those who have had experience with oral health literacy miscommunication events perceive barriers to effective communication as more significant.

Life expectancy in elderly patients following burns injury.

PubMed

Sepehripour, Sarvnaz; Duggineni, Sirisha; Shahsavari, Somaya; Dheansa, Baljit

2018-05-18

Burn injuries commonly occur in vulnerable age and social groups. Previous research has shown that frailty may represent a more important marker of adverse outcome in healthcare rather than chronological age (Roberts et al., 2012). In this paper we determined the relationship between burn injury, frailty, co-morbidities and long-term survival. Retrospective data collection from patients aged 75 with burns injuries, treated and discharged at Queen Victoria Hospital. The Clinical Frailty Scale (Rockwood et al., 2005) was used to calculate frailty at the time of admission. The expected mortality age (life expectancy) of deceased patients was obtained from two survival predictors. The data shows a statistically significant correlation between frailty score and complications and a statistically significant correlation between total body surface area percentage and complications. No significant difference was found between expected and observed age of death or life expectancy amongst the deceased (p value of 0.109). Based on the data from our unit, sustaining a burn as an elderly person does not reduce life expectancy. Medical and surgical complications, immediate, early and late, although higher with greater frailty and TBSA of burn, but do not adversely affect survival in this population. Copyright © 2018 Elsevier Ltd. All rights reserved.

Preoperative and post-operative sleep quality evaluation in rotator cuff tear patients.

PubMed

Serbest, Sancar; Tiftikçi, Uğur; Askın, Aydogan; Yaman, Ferda; Alpua, Murat

2017-07-01

The aim of this study was to examine the potential relationship between subjective sleep quality and degree of pain in patients with rotator cuff repair. Thirty-one patients who underwent rotator cuff repair prospectively completed the Pittsburgh Sleep Quality Index, the Western Ontario Rotator Cuff Index, and the Constant and Murley shoulder scores before surgery and at 6 months after surgery. Preoperative demographic, clinical, and radiologic parameters were also evaluated. The study analysed 31 patients with a median age of 61 years. There was a significant difference preoperatively versus post-operatively in terms of all PSQI global scores and subdivisions (p < 0.001). A statistically significant improvement was determined by the Western Ontario Rotator Cuff Scale and the Constant and Murley shoulder scores (p ˂ 0.001). Sleep disorders are commonly seen in patients with rotator cuff tear, and after repair, there is an increase in the quality of sleep with a parallel improvement in shoulder functions. However, no statistically significant correlation was determined between arthroscopic procedures and the size of the tear and sleep quality. It is suggested that rotator cuff tear repair improves the quality of sleep and the quality of life. IV.

Influence of skin peeling procedure in allergic contact dermatitis.

PubMed

Kim, Jung Eun; Park, Hyun Jeong; Cho, Baik Kee; Lee, Jun Young

2008-03-01

The prevalence of allergic contact dermatitis in patients who have previously undergone skin peeling has been rarely studied. We compared the frequency of positive patch test (PT) reactions in a patient group with a history of peeling, to that of a control group with no history of peeling. The Korean standard series and cosmetic series were performed on a total of 262 patients. 62 patients had previously undergone peeling and 200 patients did not. The frequency of positive PT reactions on Korean standard series was significantly higher in the peeling group compared with that of the control group (P < 0.05, chi-square test). However, the most commonly identified allergens were mostly cosmetic-unrelated allergens. The frequency of positive PT reactions on cosmetic series in the peeling group was higher than that of the control group, but lacked statistical significance. The frequency (%) of positive PT reactions on cosmetic series in the high-frequency peel group was higher than that of the low-frequency group, but lacked statistical significance. It appears peeling may not generally affect the development of contact sensitization. Further work is required focusing on the large-scale prospective studies by performing a PT before and after peeling.

Statistically validated network of portfolio overlaps and systemic risk

PubMed Central

Gualdi, Stanislao; Cimini, Giulio; Primicerio, Kevin; Di Clemente, Riccardo; Challet, Damien

2016-01-01

Common asset holding by financial institutions (portfolio overlap) is nowadays regarded as an important channel for financial contagion with the potential to trigger fire sales and severe losses at the systemic level. We propose a method to assess the statistical significance of the overlap between heterogeneously diversified portfolios, which we use to build a validated network of financial institutions where links indicate potential contagion channels. The method is implemented on a historical database of institutional holdings ranging from 1999 to the end of 2013, but can be applied to any bipartite network. We find that the proportion of validated links (i.e. of significant overlaps) increased steadily before the 2007–2008 financial crisis and reached a maximum when the crisis occurred. We argue that the nature of this measure implies that systemic risk from fire sales liquidation was maximal at that time. After a sharp drop in 2008, systemic risk resumed its growth in 2009, with a notable acceleration in 2013. We finally show that market trends tend to be amplified in the portfolios identified by the algorithm, such that it is possible to have an informative signal about institutions that are about to suffer (enjoy) the most significant losses (gains). PMID:28000764

Statistical representation of multiphase flow

NASA Astrophysics Data System (ADS)

Subramaniam

2000-11-01

The relationship between two common statistical representations of multiphase flow, namely, the single--point Eulerian statistical representation of two--phase flow (D. A. Drew, Ann. Rev. Fluid Mech. (15), 1983), and the Lagrangian statistical representation of a spray using the dropet distribution function (F. A. Williams, Phys. Fluids 1 (6), 1958) is established for spherical dispersed--phase elements. This relationship is based on recent work which relates the droplet distribution function to single--droplet pdfs starting from a Liouville description of a spray (Subramaniam, Phys. Fluids 10 (12), 2000). The Eulerian representation, which is based on a random--field model of the flow, is shown to contain different statistical information from the Lagrangian representation, which is based on a point--process model. The two descriptions are shown to be simply related for spherical, monodisperse elements in statistically homogeneous two--phase flow, whereas such a simple relationship is precluded by the inclusion of polydispersity and statistical inhomogeneity. The common origin of these two representations is traced to a more fundamental statistical representation of a multiphase flow, whose concepts derive from a theory for dense sprays recently proposed by Edwards (Atomization and Sprays 10 (3--5), 2000). The issue of what constitutes a minimally complete statistical representation of a multiphase flow is resolved.

[Effect of vinegar-processed Curcumae Rhizoma on bile metabolism in rats].

PubMed

Gu, Wei; Lu, Tu-Lin; Li, Jin-Ci; Wang, Qiao-Han; Pan, Zi-Hao; Ji, De; Li, Lin; Zhang, Ji; Mao, Chun-Qin

2016-04-01

To explore the effect of vinegar-processed Curcumae Rhizoma on endogenous metabolites in bile by investigating the endogenous metabolites difference in bile before and after Curcumae Rhizoma was processed with vinegar. Alcohol extracts of crude and vinegar-processed Curcumae Rhizoma, as well as normal saline were prepared respectively, which were then given to the rats by intragastric administration for 0.5 h. Then common bile duct intubation drainage was conducted to collect 12 h bile of the rats. UPLC-TOF-MS analysis of bile samples was applied after 1∶3 acetonitrile protein precipitation; unidimensional statistics were combined with multivariate statistics and PeakView software was compared with network database to identify the potential biomarkers. Vinegar-processed Curcumae Rhizoma extracts had significant effects on metabolites spectrum in bile of the rats. With the boundaries of P<0.05, 13 metabolites with significant differences were found in bile of crude and vinegar-processed Curcumae Rhizoma groups, and 8 of them were identified when considering the network database. T-test unidimensional statistical analysis was applied between administration groups and blank group to obtain 7 metabolites with significant differences and identify them as potential biomarkers. 6 of the potential biomarkers were up-regulated in vinegar-processed group, which were related to the metabolism regulation of phospholipid metabolism, fat metabolism, bile acid metabolism, and N-acylethanolamine hydrolysis reaction balance, indicating the mechanism of vinegar-processed Curcumae Rhizoma on endogenous metabolites in bile of the rats. Copyright© by the Chinese Pharmaceutical Association.

Role Of Symptomatic Treatment In Comparison To Antibiotics In Uncomplicated Urinary Tract Infections.

PubMed

Jamil, Muhammad Nasir; Farooq, Umer; Sultan, Babar; Khan, Raza Muhammad

2016-01-01

Uncomplicated urinary tract infections (UTIs) are the most common bacterial infections among women presenting to primary care causing rapidly increasing strains of resistant bacteria to the growing antibiotic industry. Restricting antibiotics to necessary indications is the only solution. The objectives of the study were to compare the efficacy of symptomatic treatment vs antibiotic in patients with uncomplicated UTI, in terms of individual symptom score, i.e., frequency, urgency, dysuria, supra pubic pain scores and total symptoms scores. A randomized control trial (RCT) in 100 women (15-50 years) with symptoms of urinary frequency, urgency, dysuria and pain supra pubic region, associated with uncomplicated UTI, at Urology department, AMI, Abbottabad. Two treatment strategies were compared in uncomplicated UTI patient). Patients were randomized to antibiotic or symptomatic treatment groups on consecutive non-probability basis (50 in each group) given for 05 days. Efficacy of medications was assessed by comparing pre and post treatment symptom scores along with the post treatment scores of both groups compared to see statistical significance of difference by independent samples t-test. There was a statistically significant difference in symptoms improvement in both treatment arms of all scores, i.e., p-value=0.000. Whereas only dysuria score was able to show a statistically significance of difference in post Rx scores comparison of both groups, p-value=0.004. Symptomatic treatment is not inferior to antibiotic treatment when proper patient selection is undertaken, resulting in decreased need for unnecessary antibiotics use.

Depression in patients with stable chronic obstructive pulmonary disease: a cross-sectional study in the national center for respiratory diseases in Indonesia.

PubMed

Rosrita, Nur Nina; Yunus, Faisal; Ginting, Tribowo Tuahta; Nurwidya, Fariz

2016-01-01

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality in the world, including Indonesia. It can cause comorbidities such as osteoporosis, heart failure, diabetes, and depression. Depression is a common. The purpose of this study is to reveal the prevalence of depression in stable COPD patients in Persahabatan Hospital Jakarta and its associated factors. This is a cross-sectional study in which stable COPD patients who visited COPD Outpatient Clinic in Persahabatan Hospital Jakarta and met the inclusion and exclusion criteria were asked for a history of disease, physical examination, lung function test and underwent Mini International Neuropsychiatric Interview Version (MINI) ICD 10. One hundred and forty-one patients were enrolled in this study. Prevalence of depression was 19.1%. Subjects with moderate-high COPD assessment test (CAT) score ≥ 10 have 14 times higher risk of having depression (p<0.001) compared to subjects with mild CAT score (< 10). There was a statistically significant association between symptoms-based COPD group (p<0.001), smoking status (p<0.007) and Brinkmann index (p<0.026) with depression. We found no statistically significant association between risk-based COPD group (p=0.799) and airflow limitation (p>1.000) with depression. The prevalence of depression in stable COPD patients in Persahabatan Hospital Jakarta was 19.1%. There was a statistically significant association between symptoms-based COPD group, smoking status, and Brinkmann index with depression in stable COPD patients.

Does the type of lithotripter affect outcomes in children with upper tract urolithiasis?

PubMed

Raza, Syed Johar; Ather, M Hammad

2009-02-01

To compare the treatment outcome and short-term safety of electrohydraulic and electromagnetic lithotripters in children. Comparative analysis of children undergoing shockwave lithotripsy (SWL) with a Dornier MPL 9000 electrohydraulic lithotripter (EHL) and a Siemens Modularis electromagnetic lithotripter (EML) was performed. All SWL treatments were performed by a single operator under the supervision of an admitting urologist. The demographic features, stone, and treatment-related parameters, including complications, were analyzed for both groups. Stone-free (SF) rates, re-treatment rate, and efficiency quotient (EQ) were calculated and compared for the two groups. Ninety-eight children had SWL for renal and proximal ureteral stones. There were 58 children in the EHL group and 40 in the EML group. There were no statistically significant differences between the groups in terms of age, sex, type of anesthesia, diagnostic modality, site, side, and size of the stones. Number of shockwaves used with EML was greater than with EHL (P < 0.00). SF rate was 95% and 77% for EHL and EML, respectively, with a statistically significant difference (P < 0.00). The re-treatment rate was equal in either group. The complication rate was higher with the EHL compared with the EML, although it did not reach statistical significance. Steinstrasse was the most common complication noted. EQ was 66% for the EHL, in comparison with 53% for the EML. The EHL has a better SF and EQ than the EML; however, short-term safety is marginally better with the EML.

The Relationship Between Organizational Culture and Organizational Commitment in Zahedan University of Medical Sciences.

PubMed

Azizollah, Arbabisarjou; Abolghasem, Farhang; Mohammad Amin, Dadgar

2015-12-14

Organizations effort is to achieve a common goal. There are many constructs needed for organizations. Organizational culture and organizational commitment are special concepts in management. The objective of the current research is to study the relationship between organizational culture and organizational commitment among the personnel of Zahedan University of Medical Sciences.  This is a descriptive- correlational study. The statistical population was whole tenured staff of Zahedan University of Medical Sciences that worked for this organization in 2012-2013. Random sampling method was used and 165 samples were chosen. Two standardized questionnaires of the organizational culture (Schein, 1984) and organizational commitment (Meyer & Allen, 2002) were applied. The face and construct validity of the questionnaires were approved by the lecturers of Management and experts. Reliability of questionnaires of the organizational culture and organizational commitment were 0.89 and 0.88 respectively, by Cronbach's Alpha coefficient. All statistical calculations performed using Statistical Package for the Social Sciences version 21.0 (SPSS Inc., Chicago, IL, USA). The level of significance was set at P<0.05. The findings of the study showed that there was a significant relationship between organizational culture and organizational commitment (P value=0.027). Also, the results showed that there was a significant relation between organizational culture and affective commitment (P-value=0.009), organizational culture and continuance commitment (P-value=0.009), and organizational culture and normative commitment (P-value=0.009).

The Relationship Between Organizational Culture and Organizational Commitment in Zahedan University of Medical Sciences

PubMed Central

Azizollah, Arbabisarjou; Abolghasem, Farhang; Amin, Dadgar Mohammad

2016-01-01

Background and Objective: Organizations effort is to achieve a common goal. There are many constructs needed for organizations. Organizational culture and organizational commitment are special concepts in management. The objective of the current research is to study the relationship between organizational culture and organizational commitment among the personnel of Zahedan University of Medical Sciences. Materials and Methods: This is a descriptive- correlational study. The statistical population was whole tenured staff of Zahedan University of Medical Sciences that worked for this organization in 2012-2013. Random sampling method was used and 165 samples were chosen. Two standardized questionnaires of the organizational culture (Schein, 1984) and organizational commitment (Meyer & Allen, 2002) were applied. The face and construct validity of the questionnaires were approved by the lecturers of Management and experts. Reliability of questionnaires of the organizational culture and organizational commitment were 0.89 and 0.88 respectively, by Cronbach’s Alpha coefficient. All statistical calculations performed using Statistical Package for the Social Sciences version 21.0 (SPSS Inc., Chicago, IL, USA). The level of significance was set at P<0.05. Findings: The findings of the study showed that there was a significant relationship between organizational culture and organizational commitment (P value=0.027). Also, the results showed that there was a significant relation between organizational culture and affective commitment (P-value=0.009), organizational culture and continuance commitment (P-value=0.009), and organizational culture and normative commitment (P-value=0.009). PMID:26925884

Epidemiology of malaria in pregnancy in central India.

PubMed Central

Singh, N.; Shukla, M. M.; Sharma, V. P.

1999-01-01

Analysis of three years of data from a malaria clinic operated by the Indian Council of Medical Research (ICMR) in the Government Medical College Hospital in Jabalpur, central India, showed a high malaria prevalence among pregnant women, which was statistically highly significant (P < 0.0001) compared with the situation among nonpregnant women. Cerebral malaria was a common complication of severe Plasmodium falciparum infection, with a high mortality during pregnancy, requiring immediate attention. The study also showed that malaria infection was more frequent in primigravidae, falling progressively with increasing parity. Mean parasite densities were significantly higher in pregnant women compared with nonpregnant women for both P. falciparum (P < 0.001; df = 137) and P. vivax (P < 0.05; df = 72) infection. Pregnant women with falciparum or vivax malaria were significantly more anaemic than noninfected pregnant women or infected nonpregnant women. The average weight of 155 neonates from infected mothers was 350 g less than that of 175 neonates from noninfected mothers. This difference in birth weight was statistically significant for both P. falciparum (P < 0.0001; df = 278) and P. vivax (P < 0.0001; df = 223) infection. Congenital malaria was not recorded. We conclude that pregnant women from this geographical area require systematic intervention owing to their high susceptibility to malaria during pregnancy and the puerperium. PMID:10444880

The Evaluation of Head and Craniocervical Posture among Patients with and without Temporomandibular Joint Disorders- A Comparative Study.

PubMed

Saddu, Shweta Channavir; Dyasanoor, Sujatha; Valappila, Nidhin J; Ravi, Beena Varma

2015-08-01

Temporomandibular disorders (TMD) are the most common non-dental cause of orofacial pain with a multifactorial aetiology. To evaluate the head and craniocervical posture between individuals with and without TMD and its sub types by photographic and radiographic method. Thirty four TMD patients diagnosed according to Research Diagnostic Criteria for TMD's (RDC/TMD) and were divided into 2 groups: Group I (muscle disorder), Group II (disc displacement). Control group comprised of 34 age and sex matched subjects without TMD. Lateral view photographs were taken and the head posture angle was measured. Craniocervical posture was assessed on lateral skull radiograph with two angles (Craniocervical Angle, Cervical Curvature Angle) and two distances (Suboccipital Space, Atlas-Axis Distance). To compare the results, t-test was used with significance level of 0.05. Head posture showed no statistical significant difference (p > 0.05) between Group I, II and control group in both photographic and radiographic methods. The cervical curvature angle showed significant difference (p = 0.045) in Group I only. Atlas-Axis Distance was statistically significant in Group II (p = 0.001). The present study confirmed that there is a negative association of head posture and TMD whereas, cervical lordosis was present in Group I only.

The Evaluation of Head and Craniocervical Posture among Patients with and without Temporomandibular Joint Disorders- A Comparative Study

PubMed Central

Saddu, Shweta Channavir; Dyasanoor, Sujatha; Ravi, Beena Varma

2015-01-01

Introduction Temporomandibular disorders (TMD) are the most common non-dental cause of orofacial pain with a multifactorial aetiology. Aim To evaluate the head and craniocervical posture between individuals with and without TMD and its sub types by photographic and radiographic method. Materials and Methods Thirty four TMD patients diagnosed according to Research Diagnostic Criteria for TMD’s (RDC/TMD) and were divided into 2 groups: Group I (muscle disorder), Group II (disc displacement). Control group comprised of 34 age and sex matched subjects without TMD. Lateral view photographs were taken and the head posture angle was measured. Craniocervical posture was assessed on lateral skull radiograph with two angles (Craniocervical Angle, Cervical Curvature Angle) and two distances (Suboccipital Space, Atlas-Axis Distance). To compare the results, t-test was used with significance level of 0.05. Results Head posture showed no statistical significant difference (p > 0.05) between Group I, II and control group in both photographic and radiographic methods. The cervical curvature angle showed significant difference (p = 0.045) in Group I only. Atlas-Axis Distance was statistically significant in Group II (p = 0.001). Conclusion The present study confirmed that there is a negative association of head posture and TMD whereas, cervical lordosis was present in Group I only. PMID:26436048

Can the Accuracy of Home Blood Glucose Monitors be affected by the Received Signal Strength of 900 MHz GSM Mobile Phones?

PubMed Central

Eslami, J.; Ghafaripour, F.; Mortazavi, S.A.R.; Mortazavi, S.M.J.; Shojaei-fard, M.B.

2015-01-01

Background People who use home blood glucose monitors may use their mobile phones in the close vicinity of medical devices. This study is aimed at investigating the effect of the signal strength of 900 MHz GSM mobile phones on the accuracy of home blood glucose monitors. Methods Sixty non-diabetic volunteer individuals aged 21 - 28 years participated in this study. Blood samples were analyzed for glucose level by using a common blood glucose monitoring system. Each blood sample was analyzed twice, within ten minutes in presence and absence of electromagnetic fields generated by a common GSM mobile phone during ringing. Blood samples were divided into 3 groups of 20 samples each. Group 1: exposure to mobile phone radiation with weak signal strength. Group2: exposure to mobile phone radiation with strong signal strength. Group3: exposure to a switched–on mobile phone with no signal strength. Results The magnitude of the changes in the first, second and third group between glucose levels of two measurements (׀ΔC׀) were 7.4±3.9 mg/dl, 10.2±4.5 mg/dl, 8.7±8.4 mg/dl respectively. The difference in the magnitude of the changes between the 1st and the 3rd groups was not statistically significant. Furthermore, the difference in the magnitude of the changes between the 2nd and the 3rd groups was not statistically significant. Conclusion Findings of this study showed that the signal strength of 900 MHz GSM mobile phones cannot play a significant role in changing the accuracy of home blood glucose monitors. PMID:26688798

Can the Accuracy of Home Blood Glucose Monitors be affected by the Received Signal Strength of 900 MHz GSM Mobile Phones?

PubMed

Eslami, J; Ghafaripour, F; Mortazavi, S A R; Mortazavi, S M J; Shojaei-Fard, M B

2015-12-01

People who use home blood glucose monitors may use their mobile phones in the close vicinity of medical devices. This study is aimed at investigating the effect of the signal strength of 900 MHz GSM mobile phones on the accuracy of home blood glucose monitors. Sixty non-diabetic volunteer individuals aged 21 - 28 years participated in this study. Blood samples were analyzed for glucose level by using a common blood glucose monitoring system. Each blood sample was analyzed twice, within ten minutes in presence and absence of electromagnetic fields generated by a common GSM mobile phone during ringing. Blood samples were divided into 3 groups of 20 samples each. Group 1: exposure to mobile phone radiation with weak signal strength. Group2: exposure to mobile phone radiation with strong signal strength. Group3: exposure to a switched-on mobile phone with no signal strength. The magnitude of the changes in the first, second and third group between glucose levels of two measurements (׀ΔC׀) were 7.4±3.9 mg/dl, 10.2±4.5 mg/dl, 8.7±8.4 mg/dl respectively. The difference in the magnitude of the changes between the 1st and the 3rd groups was not statistically significant. Furthermore, the difference in the magnitude of the changes between the 2nd and the 3rd groups was not statistically significant. Findings of this study showed that the signal strength of 900 MHz GSM mobile phones cannot play a significant role in changing the accuracy of home blood glucose monitors.

The Pattern of Antibiotic Prescribing by Dental Practitioners in Zagreb, Croatia.

PubMed

Perić, Marina; Perković, Ivana; Romić, Martina; Simeon, Paris; Matijević, Jurica; Mehičić, Goranka Prpić; Krmek, Silvana Jukić

2015-06-01

Bacterial resistance is considered a consequence of misuse or overuse of antibiotics. Dentistry significantly contributes to this increasing public health problem. The aim of this cross-sectional study was to examine the pattern of antibiotics prescribed by Croatian dentists in Zagreb area. Out of 220 Doctors of Dental Medicine (DMDs) from Zagreb 110 responded to survey. Prior to the research an ethical approval was obtained. Participants were directly contacted. The questionnaire consisted of two parts: general data on DMDs and the part concerning indications, duration, type and dosage of antibiotic therapy. Data were processed using MS Excel and SPSS for Windows, Version 17.0. Statistical significance was tested by Fisher's exact test, chi-square test, Mann-Whitney U test and Spearman's rank correlation at the level of statistical significance p<0.05. During the period of two months, the doctors prescribed antibiotics to 1,500 patients, 690 (46%) were men and 810 (54%) women. The most often prescribed antibiotics were penicillin (72.5% of patients), represented mostly by amoxicillin in combination with clavulanic acid (57.6%). The most common indication for the prescribed antibiotics was periapical or periodontal abscess (44%). Definite clinical indication (71.2%) was stated as the most common reason for antibiotic prescription. Antibiotic therapy usually lasted 7 days (62.9%). The doctors prescribed daily doses of antibiotics according to the instructions for the use of specific drugs. The examined subjects prescribe antibiotics according to the curriculum taught at the School of Dental Medicine for majority of types, doses and duration of the treatments, although antibiotics over-prescription in cases without medical indication was observed. The national guidelines on antibiotic regimens are required in order to reduce unnecessary antibiotic use. Copyright© by the National Institute of Public Health, Prague 2015.

Ocular manifestations of rheumatoid arthritis and their correlation with anti-cyclic citrullinated peptide antibodies.

PubMed

Vignesh, Ammapati Paul Pandian; Srinivasan, Renuka

2015-01-01

To study the ocular manifestations of rheumatoid arthritis and to correlate the role of anti-cyclic citrullinated peptide antibody (anti-CCP antibody) with the ocular manifestations. Three-hundred and ninety-two eyes of the 196 rheumatoid arthritis patients who attended the ophthalmology outpatient department underwent a detailed ocular examination using slit lamp biomicroscopy and ophthalmoscopy. The tear function of all the patients was assessed using Schirmer's test, tear film break-up time and ocular surface staining. The anti-CCP antibody titers for all the rheumatoid arthritis patients were estimated using enzyme-linked immunosorbent assay tests. Seventy-seven patients (135 eyes, 39%) out of the 196 patients studied had ocular manifestations typical of rheumatoid arthritis. Dry eye was the most common manifestation (28%, 54 patients). Of the patients, 78% was females (60 patients). The mean duration of rheumatoid arthritis in patients with ocular manifestations was 5.4±2.7 years and without ocular manifestations was 2.1±1.6years. Three percent of the patients had episcleritis (six patients). Scleritis was present in 2% of the patients (four patients). Peripheral ulcerative keratitis and sclerosing keratitis was present in 1% of the population each (two patients each). Eighty-five percent (66 patients) had bilateral manifestations 15% (eleven patients) had unilateral manifestations. There was a strong association between the presence of anti-CCP antibodies and ocular manifestations of rheumatoid arthritis which was shown by the statistically significant P-value of <0.0001. Ocular manifestations are a significant part of the extra-articular manifestation of rheumatoid arthritis. Dry eye was the most common ocular manifestation. There was a statistically significant association between the presence of anti-CCP antibodies specific to rheumatoid arthritis and the ocular manifestations.

Marmara University Medical Students' Perception on Sexual Violence against Women and Induced Abortion in Turkey.

PubMed

Lüleci, Nimet Emel; Kaya, Eda; Aslan, Ece; Şenkal, Ece Söylem; Çiçek, Zehra Nadide

2016-03-01

Historically, sexual assault is a common issue in Turkey. As doctors are one of the steps to help sexually assaulted women, medical students should have basic knowledge of and sensitivity regarding this subject. Another common women's public health issue is induced abortion. In countries where access to abortion is restricted, there is a tendency towards unhealthy abortion. The aims of this study are: (1) to determine the attitudes and opinions of Marmara University Medical Faculty students about sexual assault against women and induced abortion and (2) to propose an educational program for medical students about sexual assault and abortion. Cross-sectional study. The questionnaires were self-administered and the data were analyzed using SPSS v.15.0. First, the descriptive statistics were analyzed, followed by Chi-square for contingency tests assessing differences in attitudes toward sexual assault and induced abortion by factors such as gender and educational term. Differences were considered statistically significant at p<0.05. About 89.6% of the participants (n=266) reported that they had never been sexually assaulted and about 11.5% of the women (n=19) had been sexually assaulted. There was no significant relationship between previous sexual assault and gender (p>0.05). Although there was no significant difference regarding the extent of punishment by victim's status as a virgin, 21.3% (n=63) agreed that punishment should be more severe when the victim was a virgin. About 40.7% (n=120) agreed that the legal period of abortion in Turkey (10 weeks) should be longer. The majority (86.1%, n=255) agreed that legally prohibiting abortions causes an increase in unhealthy abortions. An educational program on these issues should be developed for medical students.

Screening CT angiography for pediatric blunt cerebrovascular injury with emphasis on the cervical "seatbelt sign".

PubMed

Desai, N K; Kang, J; Chokshi, F H

2014-09-01

There are no standard screening guidelines to evaluate blunt cerebrovascular injury in children. The purpose of this retrospective study was to understand the clinical and radiologic risk factors associated with pediatric blunt cerebrovascular injury on CTA of the neck with primary attention to the cervical "seatbelt sign." Radiology reports from 2002 to 2012 were queried for the examination "CTA neck." The electronic medical record was reviewed for mechanism of injury, Glasgow Coma Scale score, and physical examination findings. Radiology reports from adjunct radiographic studies were reviewed. CTA neck examinations with reported blunt cerebrovascular injury were reviewed to confirm imaging findings. Patients with penetrating injury or those without a history of trauma were excluded. Four hundred sixty-three patients underwent CTA of the neck; 137 had blunt trauma. Forty-two of 85 patients involved in a motor vehicle collision had a cervical seatbelt sign; none had blunt cerebrovascular injury. Nine vessels (4 vertebral arteries, 4 ICAs, 1 common carotid artery) in 8 patients ultimately were diagnosed with various grades (I-IV) of blunt cerebrovascular injury, representing 5.8% (8/137) of the population screened for blunt neck trauma. The mean Glasgow Coma Scale score was significantly lower (P=.02) in the blunt cerebrovascular injury group versus the non-blunt cerebrovascular injury group. Although not statistically significant, patients with blunt cerebrovascular injury had a higher tendency to have additional traumatic injuries, primarily basilar skull fractures (P=.05) and intracranial hemorrhage (P=.13). A common indication for neck CTA, the cervical seatbelt sign, was not associated with blunt cerebrovascular injury. With the exception of Glasgow Coma Scale score, no single risk factor was statistically significant in predicting vascular injury in this series. © 2014 by American Journal of Neuroradiology.

Sex differences in mechanical allodynia: how can it be preclinically quantified and analyzed?

PubMed Central

Nicotra, Lauren; Tuke, Jonathan; Grace, Peter M.; Rolan, Paul E.; Hutchinson, Mark R.

2014-01-01

Translating promising preclinical drug discoveries to successful clinical trials remains a significant hurdle in pain research. Although animal models have significantly contributed to understanding chronic pain pathophysiology, the majority of research has focused on male rodents using testing procedures that produce sex difference data that do not align well with comparable clinical experiences. Additionally, the use of animal pain models presents ongoing ethical challenges demanding continuing refinement of preclinical methods. To this end, this study sought to test a quantitative allodynia assessment technique and associated statistical analysis in a modified graded nerve injury pain model with the aim to further examine sex differences in allodynia. Graded allodynia was established in male and female Sprague Dawley rats by altering the number of sutures placed around the sciatic nerve and quantified by the von Frey test. Linear mixed effects modeling regressed response on each fixed effect (sex, oestrus cycle, pain treatment). On comparison with other common von Frey assessment techniques, utilizing lower threshold filaments than those ordinarily tested, at 1 s intervals, appropriately and successfully investigated female mechanical allodynia, revealing significant sex and oestrus cycle difference across the graded allodynia that other common behavioral methods were unable to detect. Utilizing this different von Frey approach and graded allodynia model, a single suture inflicting less allodynia was sufficient to demonstrate exaggerated female mechanical allodynia throughout the phases of dioestrus and pro-oestrus. Refining the von Frey testing method, statistical analysis technique and the use of a graded model of chronic pain, allowed for examination of the influences on female mechanical nociception that other von Frey methods cannot provide. PMID:24592221

Facial Acanthosis Nigricans: A Morphological Marker of Metabolic Syndrome

PubMed Central

Panda, Saumya; Das, Anupam; Lahiri, Koushik; Chatterjee, Manas; Padhi, Tanmay; Rathi, Sanjay; Dhar, Sandipan; Sarma, Nilendu

2017-01-01

Introduction: Acanthosis nigricans (AN) is a frequently encountered entity. Facial AN (FAN) is a subset of AN which is being increasingly recognized. Recently, reports hypothesizing the association of FAN with features of metabolic syndrome have been published. Aims and Objectives: The aim of this study was to study the clinicodemographic profile of patients with FAN, and to assess the correlation of hypertension, increased waist–hip ratio (WHR), increased body mass index (BMI), type 2 diabetes mellitus, deranged lipid profile, serum insulin, and impaired oral glucose tolerance test (OGTT) (parameters of metabolic syndrome) in these patients, as well as to determine the most significant predictor (highest relative risk) of development of FAN. Methods: A multicentric case–control study was conducted (123 cases in each group) over a period of 2 years. Data were obtained on the basis of history, examination, and relevant laboratory investigations. Statistical analysis was done using Statistica version 6 (StatSoft Inc., 2001, Tulsa, Oklahoma, USA), SPSS statistics version 17 (SPSS Inc., 2008, Illinois, Chicago, USA), and GraphPad Prism version 5 (GraphPad Software Inc., 2007, San Diego, California, USA). Results: Mean age of the patients with FAN was 38.83 ± 8.62 years. Mean age of onset of the disease was 30.93 ± 8.18 years. The most common site of face involved was the forehead and temporal region. The most common pigmentation was brown-black. Male sex, positive OGTT, increased WHR, and increased BMI were most significantly related to FAN. Smoking was found to have a protective effect against the development of FAN. Conclusion: Here, we document a significant association between male patients with positive OGTT, increased WHR, and BMI and FAN. Thus, we propose that FAN could be considered a morphological marker of metabolic syndrome. PMID:29263532

Role of Pro-Inflammatory Cytokines and Vitamin D in Probable Alzheimer's Disease with Depression

PubMed Central

Banerjee, Anindita; Khemka, Vineet Kumar; Roy, Debashree; Dhar, Aparajita; Sinha Roy, Tapan Kumar; Biswas, Atanu; Mukhopadhyay, Barun; Chakrabarti, Sasanka

2017-01-01

Symptoms of depression are present in a significant proportion of Alzheimer's disease (AD) patients. While epidemiological studies have shown a strong association between depression and AD, it has not been established whether depression is a risk factor or merely a co-morbidity of AD. It is also uncertain if depression affects the pathogenesis of AD. In this paper, we address these questions by measuring the serum levels of two common metabolic risk factors of AD and depression, inflammatory cytokines (IL 6 and TNF alpha) and serum 25-hydroxyvitamin D, in a case-control study. We measured the serum levels of IL 6, TNF α and 25-hydroxyvitamin D in age-matched healthy controls (n= 60) and in AD patients without depression (n=26) or AD patients with depression (n=34), and statistically analyzed the changes in these parameters among different groups under this study. Our results show that in AD there is a significant increase in IL 6 and TNF α and a marked decrease in 25-hydroxyvitamin D in the peripheral circulation compared to age-matched healthy controls. Furthermore, AD patients with depression have even significantly higher levels of IL 6 or TNF α and a lower level of 25-hydroxyvitamin D in circulation than in AD patients without depression. We also found a strong statistical correlation between the disease severity and the serum levels of IL 6, TNF α and 25-hydroxyvitamin D in AD patients with depression. These results suggest that altered circulating levels of common metabolic risk factors lead to the co-existence of depression with AD in many patients, and when they co-exist, the depression presumably affects the severity of AD presentations through more aggravated changes in these risk factors. PMID:28580183

Marmara University Medical Students’ Perception on Sexual Violence against Women and Induced Abortion in Turkey

PubMed Central

Lüleci, Nimet Emel; Kaya, Eda; Aslan, Ece; Şenkal, Ece Söylem; Çiçek, Zehra Nadide

2016-01-01

Background: Historically, sexual assault is a common issue in Turkey. As doctors are one of the steps to help sexually assaulted women, medical students should have basic knowledge of and sensitivity regarding this subject. Another common women’s public health issue is induced abortion. In countries where access to abortion is restricted, there is a tendency towards unhealthy abortion. Aims: The aims of this study are: (1) to determine the attitudes and opinions of Marmara University Medical Faculty students about sexual assault against women and induced abortion and (2) to propose an educational program for medical students about sexual assault and abortion. Study Design: Cross-sectional study. Methods: The questionnaires were self-administered and the data were analyzed using SPSS v.15.0. First, the descriptive statistics were analyzed, followed by Chi-square for contingency tests assessing differences in attitudes toward sexual assault and induced abortion by factors such as gender and educational term. Differences were considered statistically significant at p<0.05. Results: About 89.6% of the participants (n=266) reported that they had never been sexually assaulted and about 11.5% of the women (n=19) had been sexually assaulted. There was no significant relationship between previous sexual assault and gender (p>0.05). Although there was no significant difference regarding the extent of punishment by victim’s status as a virgin, 21.3% (n=63) agreed that punishment should be more severe when the victim was a virgin. About 40.7% (n=120) agreed that the legal period of abortion in Turkey (10 weeks) should be longer. The majority (86.1%, n=255) agreed that legally prohibiting abortions causes an increase in unhealthy abortions. Conclusion: An educational program on these issues should be developed for medical students. PMID:27403386

Cytopathology of non-invasive follicular thyroid neoplasm with papillary-like nuclear features: A comparative study with similar patterned papillary thyroid carcinoma variants.

PubMed

Mahajan, S; Agarwal, S; Kocheri, N; Jain, D; Mathur, S R; Iyer, V K

2018-06-01

Noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) is a recently described, indolent thyroid tumor, with well-defined histopathological diagnostic criteria. Cytology features are not well documented. We reviewed cytology of histologically proven cases of NIFTP and some of its common differentials to look for salient diagnostic features. Cases reported on histopathology as follicular variant of papillary thyroid carcinoma (FVPTC), or NIFTP between July 2015 and April 2017 having available cytology smears were retrieved and reclassified as NIFTP, FVPTC, and classical papillary thyroid carcinoma with predominant follicular pattern (PTC-FP). Cytological features were assessed, classified as per The Bethesda System for Reporting Cytopathology and compared. There were 23 NIFTP cases, 18 FVPTC and 8 PTC-FP. A microfollicle-predominant pattern was seen in all. Nuclear score was 2 in most NIFTP cases (61%). Pseudoinclusions were absent. NIFTP showed features of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) (III) in 61%, follicular neoplasm/suspicious for a follicular neoplasm (FN/SFN) (IV) in 35% and suspicious for malignancy (SFM) (V) in 4%. Most of the FVPTCs were also called FN/SFN (IV) (56%) or AUS/FLUS (III) (22%). Nuclear features did not statistically differ from NIFTP. PTC-FP showed high-grade cytology in 75%, and higher nuclear score (3 in 75%) in contrast to NIFTP (P = .003). NIFTP and FVPTC show a similar distribution among the Bethesda categories hence precluding conclusive distinction on cytology. PTC-FP, in contrast, was found to have a statistically significant higher nuclear score and more commonly showed malignant cytology. © 2018 John Wiley & Sons Ltd.

Association analysis of 9,560 prostate cancer cases from the International Consortium of Prostate Cancer Genetics confirms the role of reported prostate-cancer associated SNPs for familial disease

PubMed Central

Teerlink, Craig C.; Thibodeau, Stephen N.; McDonnell, Shannon K.; Schaid, Daniel J.; Rinckleb, Antje; Maier, Christiane; Vogel, Walther; Cancel-Tassin, Geraldine; Egrot, Christophe; Cussenot, Olivier; Foulkes, William D.; Giles, Graham G.; Hopper, John L.; Severi, Gianluca; Eeles, Ros; Easton, Douglas; Kote-Jarai, Zsofia; Guy, Michelle; Cooney, Kathleen A.; Ray, Anna M.; Zuhlke, Kimberly A.; Lange, Ethan M.; FitzGerald, Liesel M.; Stanford, Janet L.; Ostrander, Elaine A.; Wiley, Kathleen E.; Isaacs, Sarah D.; Walsh, Patrick C.; Isaacs, William B.; Wahlfors, Tiina; Tammela, Teuvo; Schleutker, Johanna; Wiklund, Fredrik; Grönberg, Henrik; Emanuelsson, Monica; Carpten, John; Bailey-Wilson, Joan; Whittemore, Alice S.; Oakley-Girvan, Ingrid; Hsieh, Chih-Lin; Catalona, William J.; Zheng, S. Lilly; Jin, Guangfu; Lu, Lingyi; Xu, Jianfeng; Camp, Nicola J.; Cannon-Albright, Lisa A.

2013-01-01

Previous GWAS studies have reported significant associations between various common SNPs and prostate cancer risk using cases unselected for family history. How these variants influence risk in familial prostate cancer is not well studied. Here, we analyzed 25 previously reported SNPs across 14 loci from prior prostate cancer GWAS. The International Consortium for Prostate Cancer Genetics (ICPCG) previously validated some of these using a family-based association method (FBAT). However, this approach suffered reduced power due to the conditional statistics implemented in FBAT. Here, we use a case-control design with an empirical analysis strategy to analyze the ICPCG resource for association between these 25 SNPs and familial prostate cancer risk. Fourteen sites contributed 12,506 samples (9,560 prostate cancer cases, 3,368 with aggressive disease, and 2,946 controls from 2,283 pedigrees). We performed association analysis with Genie software which accounts for relationships. We analyzed all familial prostate cancer cases and the subset of aggressive cases. For the familial prostate cancer phenotype, 20 of the 25 SNPs were at least nominally associated with prostate cancer and 16 remained significant after multiple testing correction (p≤1E−3) occurring on chromosomal bands 6q25, 7p15, 8q24, 10q11, 11q13, 17q12, 17q24, and Xp11. For aggressive disease, 16 of the SNPs had at least nominal evidence and 8 were statistically significant including 2p15. The results indicate that the majority of common, low-risk alleles identified in GWAS studies for all prostate cancer also contribute risk for familial prostate cancer, and that some may be contribute risk to aggressive disease. PMID:24162621

Comparative study to evaluate the accuracy of polyether occlusal bite registration material and occlusal registration wax as a guide for occlusal reduction during tooth preparation.

PubMed

Joshi, Niranjan; Shetty, Sridhar N; Prasad, Krishna D

2013-01-01

The use of different materials and techniques has been studied to decide the safest quantum of reduction of the occlusal surfaces. However, these methods provide limited information as to the actual amount of reduction with limitations in accuracy, accessibility and complexity. The objective of this study was to compare and evaluate the reliability of the most commonly used occlusal registration wax that with polyether bite registration material as a guide for occlusal reduction required during tooth preparations. For the purpose of this study, 25 abutment teeth requiring tooth preparation for fixed prosthesis were selected and tooth preparations carried out. Modeling wax strips of specific dimensions were placed onto the cast of prepared tooth, which was mounted on maximum intercuspation on the articulator and the articulator was closed. The thickness of the wax registration was measured at three zones namely two functional cusps and central fossa. Similar measurements were made using the polyether bite registration material and prosthesis at the same zones. The data was tabulated and was subjected to statistical analysis using anova test and Tukey honestly significant difference test. The differences in thickness between wax record and prosthesis by 0.1346 mm, whereas the difference between polyether and prosthesis was 0.02 mm with a P value of 0.042, which is statistically significant. This means that the wax record was 8.25% larger than the prosthesis while polyether was just 1.27% larger than the prosthesis. The clinical significance of the above analysis is that Ramitec polyether bite registration material is most suitable material when compared with commonly used modeling wax during the tooth preparation.

Indications and Visual Outcome of Penetrating Keratoplasty in Tertiary Eye Care Institute in Uttarakhand

PubMed Central

Gupta, Neeti; Dhasmana, Renu; Nagpal, Ramesh Chander; Bahadur, Harsh; Maitreya, Amit

2016-01-01

Introduction Corneal blindness forms significant proportion of visual blindness in developing countries and penetrating keratoplasty (PK) can restore vision for this. The prognosis of PK is dependent on the corneal diseases responsible for corneal blindness. Aim To evaluate the indications and visual outcome of PK in tertiary eye care institute in Uttarakhand. Materials and Methods Data was reviewed from the medical records of 145 PK done in Department of Ophthalmology, Himalayan Institute of Medical Sciences from January 2012 to October 2014. Analysis of data was done for evaluation of the indications and visual outcome by Paired student’s t-test for hypothesis testing of grouped values of preoperative and last follow-up best corrected visual acuity in cases of optical and therapeutic grafts. A p-value < 0.05 was considered statistically significant. Results In this study data of 145 eyes of 138 patients was reviewed. The most common indication for keratoplasty was corneal scarring including adherent leucoma 48 (33.10%). Therapeutic keratoplasty was done for 33 cases with maximum 30(20.68%) cases of infectious keratitis. One case of tectonic graft was included in therapeutic keratoplasty group for analysis. There was statistically significant difference (p=.0001) in best corrected visual acuity improvement from 1.39 logMAR+ 0.022(SD) preoperatively to 0.367 logMAR+0.44(SD) postoperatively and 1.4 logMAR+.000(SD) preoperatively to 0.16 logMAR+0.57(SD) postoperatively for optical and therapeutic grafts respectively. Conclusion Infective keratitis either active or healed was the major indication for keratoplasty. Poor prognosis indications were most common in this part of the country. The visual outcome following corneal transplantation was encouraging particularly in cases of optical keratoplasty. PMID:27504319