Profile of non-fatal injuries due to road traffic accidents from a industrial town in India.

PubMed

Bayan, Pankaj; Bhawalkar, J S; Jadhav, S L; Banerjee, Amitav

2013-01-01

India has one of the highest road traffic accident rates in the world. To lessen this burden, information on the contributing factors is necessary. We studied a series of cases of non-fatal road traffic accidents in two tertiary care hospitals in Pimpri, Pune, India. A total of 212 non-fatal road traffic accidents admitted over a period of one year in these two hospitals constituted the study sample. The study variables were, the gender of the accident victims, mode of accident, days of week on which the accident took place, time of day when the injury was sustained, part of the body injured, nature of injury, and self-reported reasons for the accident. data were summarized using percentages. The Chi-square test for goodness of fit was applied, to see whether there was any association between the different weekdays or time of day and the accidents. MALE : female ratio was almost 5 : 1, which was statistically significant (Chi-Square for goodness of fit = 95.11, df = 1, P < 0.0001). The maximum accidents occurred on Sundays and Mondays and the least around midweek (Wednesday). This pattern was also statistically significant (Chi-square for goodness of fit = 30.09, df = 6, P < 0.001). Pedestrians were the most vulnerable group, followed by drivers and pillions of two wheelers. These categories of road users contributed to almost 80% of the cases of Road Traffic Injuries (RTIs). Accidents were more likely in the time zone of 8 pm to midnight, followed by 4 pm to 8 pm (Chi-square for goodness of fit = 89.58, df = 5, P < 0.0001). A majority of the patients sustained multiple injuries followed by injuries to the lower limbs. A majority reported impaired visibility and fatigue as the cause of accident. Almost half (46.22%) of the injured admitted to drinking alcohol on a regular basis. Wide pavements and safe zebra crossings should be provided for pedestrians, as the highest casualty in this study were pedestrians. More accidents occurred on Sundays and Mondays and in the late evenings. Extra supervision by traffic police may be considered on Sundays / Holidays and the day following. Roads should be well lit to improve visibility after sunset.

Profile of non-fatal injuries due to road traffic accidents from a industrial town in India

PubMed Central

Bayan, Pankaj; Bhawalkar, J. S.; Jadhav, S. L.; Banerjee, Amitav

2013-01-01

Background: India has one of the highest road traffic accident rates in the world. To lessen this burden, information on the contributing factors is necessary. Materials and Methods: We studied a series of cases of non-fatal road traffic accidents in two tertiary care hospitals in Pimpri, Pune, India. A total of 212 non-fatal road traffic accidents admitted over a period of one year in these two hospitals constituted the study sample. The study variables were, the gender of the accident victims, mode of accident, days of week on which the accident took place, time of day when the injury was sustained, part of the body injured, nature of injury, and self-reported reasons for the accident. Statistical Analysis: data were summarized using percentages. The Chi-square test for goodness of fit was applied, to see whether there was any association between the different weekdays or time of day and the accidents. Results: Male : female ratio was almost 5 : 1, which was statistically significant (Chi-Square for goodness of fit = 95.11, df = 1, P < 0.0001). The maximum accidents occurred on Sundays and Mondays and the least around midweek (Wednesday). This pattern was also statistically significant (Chi-square for goodness of fit = 30.09, df = 6, P < 0.001). Pedestrians were the most vulnerable group, followed by drivers and pillions of two wheelers. These categories of road users contributed to almost 80% of the cases of Road Traffic Injuries (RTIs). Accidents were more likely in the time zone of 8 pm to midnight, followed by 4 pm to 8 pm (Chi-square for goodness of fit = 89.58, df = 5, P < 0.0001). A majority of the patients sustained multiple injuries followed by injuries to the lower limbs. A majority reported impaired visibility and fatigue as the cause of accident. Almost half (46.22%) of the injured admitted to drinking alcohol on a regular basis. Conclusion: Wide pavements and safe zebra crossings should be provided for pedestrians, as the highest casualty in this study were pedestrians. More accidents occurred on Sundays and Mondays and in the late evenings. Extra supervision by traffic police may be considered on Sundays / Holidays and the day following. Roads should be well lit to improve visibility after sunset. PMID:23724378

Measurement invariance via multigroup SEM: Issues and solutions with chi-square-difference tests.

PubMed

Yuan, Ke-Hai; Chan, Wai

2016-09-01

Multigroup structural equation modeling (SEM) plays a key role in studying measurement invariance and in group comparison. When population covariance matrices are deemed not equal across groups, the next step to substantiate measurement invariance is to see whether the sample covariance matrices in all the groups can be adequately fitted by the same factor model, called configural invariance. After configural invariance is established, cross-group equalities of factor loadings, error variances, and factor variances-covariances are then examined in sequence. With mean structures, cross-group equalities of intercepts and factor means are also examined. The established rule is that if the statistic at the current model is not significant at the level of .05, one then moves on to testing the next more restricted model using a chi-square-difference statistic. This article argues that such an established rule is unable to control either Type I or Type II errors. Analysis, an example, and Monte Carlo results show why and how chi-square-difference tests are easily misused. The fundamental issue is that chi-square-difference tests are developed under the assumption that the base model is sufficiently close to the population, and a nonsignificant chi-square statistic tells little about how good the model is. To overcome this issue, this article further proposes that null hypothesis testing in multigroup SEM be replaced by equivalence testing, which allows researchers to effectively control the size of misspecification before moving on to testing a more restricted model. R code is also provided to facilitate the applications of equivalence testing for multigroup SEM. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

NLINEAR - NONLINEAR CURVE FITTING PROGRAM

NASA Technical Reports Server (NTRS)

Everhart, J. L.

1994-01-01

A common method for fitting data is a least-squares fit. In the least-squares method, a user-specified fitting function is utilized in such a way as to minimize the sum of the squares of distances between the data points and the fitting curve. The Nonlinear Curve Fitting Program, NLINEAR, is an interactive curve fitting routine based on a description of the quadratic expansion of the chi-squared statistic. NLINEAR utilizes a nonlinear optimization algorithm that calculates the best statistically weighted values of the parameters of the fitting function and the chi-square that is to be minimized. The inputs to the program are the mathematical form of the fitting function and the initial values of the parameters to be estimated. This approach provides the user with statistical information such as goodness of fit and estimated values of parameters that produce the highest degree of correlation between the experimental data and the mathematical model. In the mathematical formulation of the algorithm, the Taylor expansion of chi-square is first introduced, and justification for retaining only the first term are presented. From the expansion, a set of n simultaneous linear equations are derived, which are solved by matrix algebra. To achieve convergence, the algorithm requires meaningful initial estimates for the parameters of the fitting function. NLINEAR is written in Fortran 77 for execution on a CDC Cyber 750 under NOS 2.3. It has a central memory requirement of 5K 60 bit words. Optionally, graphical output of the fitting function can be plotted. Tektronix PLOT-10 routines are required for graphics. NLINEAR was developed in 1987.

Associations among selected motor skills and health-related fitness: indirect evidence for Seefeldt's proficiency barrier in young adults?

PubMed

Stodden, David F; True, Larissa K; Langendorfer, Stephen J; Gao, Zan

2013-09-01

This exploratory study examined the notion of Seefeldt's (1980) hypothesized motor skill "proficiency barrier" related to composite levels of health-related physical fitness (HRF) in young adults. A motor skill competence (MSC) index composed of maximum throwing and kicking speed and jumping distance in 187 young adults aged 18 to 25 years old was evaluated against a composite index of 5 health-related fitness (HRF) test scores. MSC (high, moderate, and low) and HRF indexes (good, fair, and poor) were categorized according to normative fitness percentile ranges. 2 separate 3-way chi-square analyses were conducted to determine the probabilities of skill predicting fitness and fitness predicting skill. Most correlations among HRF and MSC variables by gender demonstrated low-to-moderate positive correlations in both men (12/15; r = .23-.58) and women (14/15; r = .21-.53). Chi-square analyses for the total sample, using composite indexes, demonstrated statistically significant predictive models, chi2(1, N = 187) = 66.99, p < .001, Cramer's V = .42. Only 3.1% of low-skilled (2 of 65) individuals were classified as having a "good" HRF. Only 1 participant (out of 65) who demonstrated high MSC was classified as having "poor" HRF (1.5%). Although individual correlations among individual MSC and HRF measures were low to moderate, these data provide indirect evidence for the possibility of a motor skill "proficiency barrier" as indicated by low composite HRF levels. This study may generate future research to address the proficiency barrier hypothesis in youth as well as adults.

Quantum chi-squared and goodness of fit testing

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

Temme, Kristan; Verstraete, Frank

2015-01-15

A quantum mechanical hypothesis test is presented for the hypothesis that a certain setup produces a given quantum state. Although the classical and the quantum problems are very much related to each other, the quantum problem is much richer due to the additional optimization over the measurement basis. A goodness of fit test for i.i.d quantum states is developed and a max-min characterization for the optimal measurement is introduced. We find the quantum measurement which leads both to the maximal Pitman and Bahadur efficiencies, and determine the associated divergence rates. We discuss the relationship of the quantum goodness of fitmore » test to the problem of estimating multiple parameters from a density matrix. These problems are found to be closely related and we show that the largest error of an optimal strategy, determined by the smallest eigenvalue of the Fisher information matrix, is given by the divergence rate of the goodness of fit test.« less

Comparative analysis through probability distributions of a data set

NASA Astrophysics Data System (ADS)

Cristea, Gabriel; Constantinescu, Dan Mihai

2018-02-01

In practice, probability distributions are applied in such diverse fields as risk analysis, reliability engineering, chemical engineering, hydrology, image processing, physics, market research, business and economic research, customer support, medicine, sociology, demography etc. This article highlights important aspects of fitting probability distributions to data and applying the analysis results to make informed decisions. There are a number of statistical methods available which can help us to select the best fitting model. Some of the graphs display both input data and fitted distributions at the same time, as probability density and cumulative distribution. The goodness of fit tests can be used to determine whether a certain distribution is a good fit. The main used idea is to measure the "distance" between the data and the tested distribution, and compare that distance to some threshold values. Calculating the goodness of fit statistics also enables us to order the fitted distributions accordingly to how good they fit to data. This particular feature is very helpful for comparing the fitted models. The paper presents a comparison of most commonly used goodness of fit tests as: Kolmogorov-Smirnov, Anderson-Darling, and Chi-Squared. A large set of data is analyzed and conclusions are drawn by visualizing the data, comparing multiple fitted distributions and selecting the best model. These graphs should be viewed as an addition to the goodness of fit tests.

A global goodness-of-fit statistic for Cox regression models.

PubMed

Parzen, M; Lipsitz, S R

1999-06-01

In this paper, a global goodness-of-fit test statistic for a Cox regression model, which has an approximate chi-squared distribution when the model has been correctly specified, is proposed. Our goodness-of-fit statistic is global and has power to detect if interactions or higher order powers of covariates in the model are needed. The proposed statistic is similar to the Hosmer and Lemeshow (1980, Communications in Statistics A10, 1043-1069) goodness-of-fit statistic for binary data as well as Schoenfeld's (1980, Biometrika 67, 145-153) statistic for the Cox model. The methods are illustrated using data from a Mayo Clinic trial in primary billiary cirrhosis of the liver (Fleming and Harrington, 1991, Counting Processes and Survival Analysis), in which the outcome is the time until liver transplantation or death. The are 17 possible covariates. Two Cox proportional hazards models are fit to the data, and the proposed goodness-of-fit statistic is applied to the fitted models.

The Apollo 16 regolith - A petrographically-constrained chemical mixing model

NASA Technical Reports Server (NTRS)

Kempa, M. J.; Papike, J. J.; White, C.

1980-01-01

A mixing model for Apollo 16 regolith samples has been developed, which differs from other A-16 mixing models in that it is both petrographically constrained and statistically sound. The model was developed using three components representative of rock types present at the A-16 site, plus a representative mare basalt. A linear least-squares fitting program employing the chi-squared test and sum of components was used to determine goodness of fit. Results for surface soils indicate that either there are no significant differences between Cayley and Descartes material at the A-16 site or, if differences do exist, they have been obscured by meteoritic reworking and mixing of the lithologies.

A goodness-of-fit test for capture-recapture model M(t) under closure

USGS Publications Warehouse

Stanley, T.R.; Burnham, K.P.

1999-01-01

A new, fully efficient goodness-of-fit test for the time-specific closed-population capture-recapture model M(t) is presented. This test is based on the residual distribution of the capture history data given the maximum likelihood parameter estimates under model M(t), is partitioned into informative components, and is based on chi-square statistics. Comparison of this test with Leslie's test (Leslie, 1958, Journal of Animal Ecology 27, 84- 86) for model M(t), using Monte Carlo simulations, shows the new test generally outperforms Leslie's test. The new test is frequently computable when Leslie's test is not, has Type I error rates that are closer to nominal error rates than Leslie's test, and is sensitive to behavioral variation and heterogeneity in capture probabilities. Leslie's test is not sensitive to behavioral variation in capture probabilities but, when computable, has greater power to detect heterogeneity than the new test.

As-built design specification for PARHIS

NASA Technical Reports Server (NTRS)

Tompkins, M. A. (Principal Investigator)

1981-01-01

The program is part of the CLASFYG package. It produces histograms of the greeness profile derived parameters alpha, beta, t sub o, and chi squared, which are computed by the CLASFYG program. Alpha is the approximate greeness rise time, beta is the approximate greeness decay time, t sub o is the spectral crop emergence date, and chi squared per degree of freedom is the goodness of fit of the actual data to the computed greeness profile. The program also produces statistical information concerning the parameters.

The Evaluation and Selection of Adequate Causal Models: A Compensatory Education Example.

ERIC Educational Resources Information Center

Tanaka, Jeffrey S.

1982-01-01

Implications of model evaluation (using traditional chi square goodness of fit statistics, incremental fit indices for covariance structure models, and latent variable coefficients of determination) on substantive conclusions are illustrated with an example examining the effects of participation in a compensatory education program on posttreatment…

An Extension of the Chi-Square Procedure for Non-NORMAL Statistics, with Application to Solar Neutrino Data

NASA Astrophysics Data System (ADS)

Sturrock, P. A.

2008-01-01

Using the chi-square statistic, one may conveniently test whether a series of measurements of a variable are consistent with a constant value. However, that test is predicated on the assumption that the appropriate probability distribution function (pdf) is normal in form. This requirement is usually not satisfied by experimental measurements of the solar neutrino flux. This article presents an extension of the chi-square procedure that is valid for any form of the pdf. This procedure is applied to the GALLEX-GNO dataset, and it is shown that the results are in good agreement with the results of Monte Carlo simulations. Whereas application of the standard chi-square test to symmetrized data yields evidence significant at the 1% level for variability of the solar neutrino flux, application of the extended chi-square test to the unsymmetrized data yields only weak evidence (significant at the 4% level) of variability.

Comparison of athletic training professional preparation to the prevalence of injury occurrence in the collegiate setting

NASA Astrophysics Data System (ADS)

Westerman, Beverly Jean

1999-10-01

This study investigated the relationship between the frequency of injuries that occur to certain body areas in National Collegiate Athletic Association (NCAA) athletes and the percentage of time teaching about the same subject areas in Athletic Training Education Programs (ATEP). Directors of Commission of Accreditation of Allied Health Education Programs (CAAHEP) accredited and National Athletic Trainers' Association (NATA) approved programs were surveyed. Randomly selected ATEP directors were interviewed by telephone to collect information on estimated teaching time, the strengths and weaknesses of their programs, and preferred teaching methods. Data were collected from the NCAA Injury Surveillance System to calculate the frequency of injury. Chi-square 'goodness-of-fit' tests were used to determine if a 'good fit' existed between injury frequency and teaching time in two categories: general body areas (head and face, upper extremity, lower extremity, spine, and abdomen and thorax) and specific body areas (head, face, upper arm and shoulder, elbow and forearm, wrist and hand, hip and pelvis, thigh, knee, lower leg, ankle and foot, cervical spine, thoracic spine, lumbar spine, abdomen, and thorax). Standardized residuals were used to assist in determining the location of statistical significance within the same two categories. The chi-square values calculated for both the general and specific body areas were greater than the critical value set at a significance level of .05 with 4 and 14 degrees of freedom respectively. Therefore, it was found that a 'good fit' does not exist between injury frequency and teaching time. The standardized residuals were calculated for each variable within the categories. One out of five general body areas and 10 out of 15 specific body areas were less than 2.00 in absolute value and were found not to contribute to the high chi-square value. Although the chi-square values showed a lack of fit between injury frequency and teaching time in the general and specific body areas, the standardized residuals indicated a relationship exists between some variables (body areas) within each category. In other words, the percentage of teaching time may correspond with injury frequency in some general and specific body areas. The responses from the program directors indicated they thought their academic programs were spending the appropriate amount of time teaching about the general and specific body areas. However, the percentages of teaching time reported for each of the body areas varied greatly among the responders. Further study is indicated to examine the relationship between teaching time/content and injury frequency.

Power of tests of normality for detecting contaminated normal samples

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

Thode, H.C. Jr.; Smith, L.A.; Finch, S.J.

1981-01-01

Seventeen tests of normality or goodness of fit were evaluated for power at detecting a contaminated normal sample. This study used 1000 replications each of samples of size 12, 17, 25, 33, 50, and 100 from six different contaminated normal distributions. The kurtosis test was the most powerful over all sample sizes and contaminations. The Hogg and weighted Kolmogorov-Smirnov tests were second. The Kolmogorov-Smirnov, chi-squared, Anderson-Darling, and Cramer-von-Mises tests had very low power at detecting contaminated normal random variables. Tables of the power of the tests and the power curves of certain tests are given.

Radar cross section models for limited aspect angle windows

NASA Astrophysics Data System (ADS)

Robinson, Mark C.

1992-12-01

This thesis presents a method for building Radar Cross Section (RCS) models of aircraft based on static data taken from limited aspect angle windows. These models statistically characterize static RCS. This is done to show that a limited number of samples can be used to effectively characterize static aircraft RCS. The optimum models are determined by performing both a Kolmogorov and a Chi-Square goodness-of-fit test comparing the static RCS data with a variety of probability density functions (pdf) that are known to be effective at approximating the static RCS of aircraft. The optimum parameter estimator is also determined by the goodness of-fit tests if there is a difference in pdf parameters obtained by the Maximum Likelihood Estimator (MLE) and the Method of Moments (MoM) estimators.

Comparison of hypertabastic survival model with other unimodal hazard rate functions using a goodness-of-fit test.

PubMed

Tahir, M Ramzan; Tran, Quang X; Nikulin, Mikhail S

2017-05-30

We studied the problem of testing a hypothesized distribution in survival regression models when the data is right censored and survival times are influenced by covariates. A modified chi-squared type test, known as Nikulin-Rao-Robson statistic, is applied for the comparison of accelerated failure time models. This statistic is used to test the goodness-of-fit for hypertabastic survival model and four other unimodal hazard rate functions. The results of simulation study showed that the hypertabastic distribution can be used as an alternative to log-logistic and log-normal distribution. In statistical modeling, because of its flexible shape of hazard functions, this distribution can also be used as a competitor of Birnbaum-Saunders and inverse Gaussian distributions. The results for the real data application are shown. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Measuring implementation behaviour of menu guidelines in the childcare setting: confirmatory factor analysis of a theoretical domains framework questionnaire (TDFQ).

PubMed

Seward, Kirsty; Wolfenden, Luke; Wiggers, John; Finch, Meghan; Wyse, Rebecca; Oldmeadow, Christopher; Presseau, Justin; Clinton-McHarg, Tara; Yoong, Sze Lin

2017-04-04

While there are number of frameworks which focus on supporting the implementation of evidence based approaches, few psychometrically valid measures exist to assess constructs within these frameworks. This study aimed to develop and psychometrically assess a scale measuring each domain of the Theoretical Domains Framework for use in assessing the implementation of dietary guidelines within a non-health care setting (childcare services). A 75 item 14-domain Theoretical Domains Framework Questionnaire (TDFQ) was developed and administered via telephone interview to 202 centre based childcare service cooks who had a role in planning the service menu. Confirmatory factor analysis (CFA) was undertaken to assess the reliability, discriminant validity and goodness of fit of the 14-domain theoretical domain framework measure. For the CFA, five iterative processes of adjustment were undertaken where 14 items were removed, resulting in a final measure consisting of 14 domains and 61 items. For the final measure: the Chi-Square goodness of fit statistic was 3447.19; the Standardized Root Mean Square Residual (SRMR) was 0.070; the Root Mean Square Error of Approximation (RMSEA) was 0.072; and the Comparative Fit Index (CFI) had a value of 0.78. While only one of the three indices support goodness of fit of the measurement model tested, a 14-domain model with 61 items showed good discriminant validity and internally consistent items. Future research should aim to assess the psychometric properties of the developed TDFQ in other community-based settings.

Structure of four executive functioning tests in healthy older adults.

PubMed

de Frias, Cindy M; Dixon, Roger A; Strauss, Esther

2006-03-01

The authors examined the factor structure of 4 indicators of executive functioning derived from 2 new (i.e., Hayling and Brixton) and 2 traditional (i.e., Stroop and Color Trails) tests. Data were from a cross-sectional sample of 55- to 85-year-old healthy adults (N=427) from the Victoria Longitudinal Study. Confirmatory factor analysis (LISREL 8.52) tested both a 2-factor model of Inhibition (Hayling, Stroop) and Shifting (Brixton, Color Trails) and a single-factor model. The 2-factor model did not fit the data because the covariance matrix of the factors was not positive definite. The single-factor model fit the data well, chi(2)(2, N=427)=0.32, p=.85, root-mean-square error of approximation (RMSEA)=.00, comparative fit index (CFI)=1.00, goodness-of-fit index (GFI)=1.00. Moreover, the single-factor structure of executive functioning was invariant (configural and metric) across gender, and invariant (configural with limited metric) across age. Structural relations showed that poorer executive functioning performance was related to older age and lower fluid intelligence, chi(2)(11, N=418)=23.04, p=.02, RMSEA=.05, CFI=.97, GFI=.98.

Probability analysis for consecutive-day maximum rainfall for Tiruchirapalli City (south India, Asia)

NASA Astrophysics Data System (ADS)

Sabarish, R. Mani; Narasimhan, R.; Chandhru, A. R.; Suribabu, C. R.; Sudharsan, J.; Nithiyanantham, S.

2017-05-01

In the design of irrigation and other hydraulic structures, evaluating the magnitude of extreme rainfall for a specific probability of occurrence is of much importance. The capacity of such structures is usually designed to cater to the probability of occurrence of extreme rainfall during its lifetime. In this study, an extreme value analysis of rainfall for Tiruchirapalli City in Tamil Nadu was carried out using 100 years of rainfall data. Statistical methods were used in the analysis. The best-fit probability distribution was evaluated for 1, 2, 3, 4 and 5 days of continuous maximum rainfall. The goodness of fit was evaluated using Chi-square test. The results of the goodness-of-fit tests indicate that log-Pearson type III method is the overall best-fit probability distribution for 1-day maximum rainfall and consecutive 2-, 3-, 4-, 5- and 6-day maximum rainfall series of Tiruchirapalli. To be reliable, the forecasted maximum rainfalls for the selected return periods are evaluated in comparison with the results of the plotting position.

[Reliability and validity of Professional Quality of Life Scale among government staff in earthquake - stricken areas in China].

PubMed

Dang, Weimin; Cheng, Wenhong; Ma, Hong; Lin, Jin; Wu, Baoming; Ma, Ning; Wang, Rongke; Xu, Junting; Zhou, Tianhang; Yu, Xin

2015-06-01

To evaluate the reliability and validity of Professional Quality of Life Scale (ProQOL-30, 4th version, 30 items) among government staff in the Wenchuan earthquake-stricken areas A total of 1,175 members of government staff in the Wenchuan earthquake-stricken areas were selected by convenience sampling and required to complete the ProQOL and Self-Reporting Questionnair (SRQ). The reliability and validity of the scale was evaluated by correlation analysis, t-test, and confirmatory factor analysis. Item-total correlation coefficients of the three subscales were 0.590 - 0.752, 0.389 - 0.603, and 0.340 - 0.647, respectively (P<0.05), and the average coefficients were 0.672, 0.482, and 0.555 respectively (P<0.05). The Cronbach's α coefficients of the three subscales were 0.864, 0.569, and 0.742 respectively, and the split-half reliabilities were 0.829, 0.490, and 0.677, respectively. P value was 0.88 in thE chi-square test of confirmatory factor analysis model. Goodness-of-fit indices of ProQOL-30 included GFI=0.895 NFI=0.856, CFI=0.895, RMSEA=0.063, and AGFI=0.912. For the ProQOL-28 as an optimized version o ProQOL-30, the Cronbach's a coefficients for burnout and trauma/compassion fatigue increased to 0.616 and 0.757, respectively. P value was 0.91 in the chi-square test of confirmatory factor analysis model test. Goodness-of-fit indices of ProQOL-28 were GFI =0.913, AGFI =0.924, NFI =0.900, CFI =0.913, and RMSEA =0.031 CONCLUSION: ProQOL-28 has good reliability and validity among government staff in the earthquake-stricker areas in China.

Geographic Information Systems to Assess External Validity in Randomized Trials.

PubMed

Savoca, Margaret R; Ludwig, David A; Jones, Stedman T; Jason Clodfelter, K; Sloop, Joseph B; Bollhalter, Linda Y; Bertoni, Alain G

2017-08-01

To support claims that RCTs can reduce health disparities (i.e., are translational), it is imperative that methodologies exist to evaluate the tenability of external validity in RCTs when probabilistic sampling of participants is not employed. Typically, attempts at establishing post hoc external validity are limited to a few comparisons across convenience variables, which must be available in both sample and population. A Type 2 diabetes RCT was used as an example of a method that uses a geographic information system to assess external validity in the absence of a priori probabilistic community-wide diabetes risk sampling strategy. A geographic information system, 2009-2013 county death certificate records, and 2013-2014 electronic medical records were used to identify community-wide diabetes prevalence. Color-coded diabetes density maps provided visual representation of these densities. Chi-square goodness of fit statistic/analysis tested the degree to which distribution of RCT participants varied across density classes compared to what would be expected, given simple random sampling of the county population. Analyses were conducted in 2016. Diabetes prevalence areas as represented by death certificate and electronic medical records were distributed similarly. The simple random sample model was not a good fit for death certificate record (chi-square, 17.63; p=0.0001) and electronic medical record data (chi-square, 28.92; p<0.0001). Generally, RCT participants were oversampled in high-diabetes density areas. Location is a highly reliable "principal variable" associated with health disparities. It serves as a directly measurable proxy for high-risk underserved communities, thus offering an effective and practical approach for examining external validity of RCTs. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

[Analysis of the impact of job characteristics and organizational support for workplace violence].

PubMed

Li, M L; Chen, P; Zeng, F H; Cui, Q L; Zeng, J; Zhao, X S; Li, Z N

2017-12-20

Objective: To analyze the effect of job characteristics and organizational support for workplace violence, explore the influence path and the theoretical model, and provide a theoretical basis for reducing workplace violence. Methods: Stratified random sampling was used to select 813 medical staff, conductors and bus drivers in Chongqing with a self-made questionnaire to investigate job characteristics, organization attitude toward workplace violence, workplace violence, fear of violence, workplace violence, etc from February to October, 2014. Amos 21.0 was used to analyze the path and to establish a theoretical model of workplace violence. Results: The odds ratio of work characteristics and organizational attitude to workplace violence were 6.033 and 0.669, respectively, and the path coefficients were 0.41 and-0.14, respectively ( P <0.05). The Fitting indexes of the model: Chi-square (χ(2)) =67.835, The ratio of the chi-square to the degree of freedom (χ(2)/df) =5.112, Good-of-fit index (GFI) =0.970, Adjusted good-of-fit index (AGFI) =0.945, Normed fit index (NFI) =0.923, Root mean square error of approximation (RMSEA) =0.071, Fit criterion (Fmin) =0.092, so the model fit well with the data. Conclusion: The job characteristic is a risk factor for workplace violence while organizational attitude is a protective factor for workplace violence, so changing the job characteristics and improving the enthusiasm of the organization to deal with workplace violence are conducive to reduce workplace violence and increase loyalty to the unit.

Comments on Different techniques for finding best-fit parameters

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

Fenimore, Edward E.; Triplett, Laurie A.

2014-07-01

A common data analysis problem is to find best-fit parameters through chi-square minimization. Levenberg-Marquardt is an often used system that depends on gradients and converges when successive iterations do not change chi-square more than a specified amount. We point out in cases where the sought-after parameter weakly affects the fit and cases where the overall scale factor is a parameter, that a Golden Search technique can often do better. The Golden Search converges when the best-fit point is within a specified range and that range can be made arbitrarily small. It does not depend on the value of chi-square.

Development and evaluation of social cognitive measures related to adolescent physical activity.

PubMed

Dewar, Deborah L; Lubans, David Revalds; Morgan, Philip James; Plotnikoff, Ronald C

2013-05-01

This study aimed to develop and evaluate the construct validity and reliability of modernized social cognitive measures relating to physical activity behaviors in adolescents. An instrument was developed based on constructs from Bandura's Social Cognitive Theory and included the following scales: self-efficacy, situation (perceived physical environment), social support, behavioral strategies, and outcome expectations and expectancies. The questionnaire was administered in a sample of 171 adolescents (age = 13.6 ± 1.2 years, females = 61%). Confirmatory factor analysis was employed to examine model-fit for each scale using multiple indices, including chi-square index, comparative-fit index (CFI), goodness-of-fit index (GFI), and the root mean square error of approximation (RMSEA). Reliability properties were also examined (ICC and Cronbach's alpha). Each scale represented a statistically sound measure: fit indices indicated each model to be an adequate-to-exact fit to the data; internal consistency was acceptable to good (α = 0.63-0.79); rank order repeatability was strong (ICC = 0.82-0.91). Results support the validity and reliability of social cognitive scales relating to physical activity among adolescents. As such, the developed scales have utility for the identification of potential social cognitive correlates of youth physical activity, mediators of physical activity behavior changes and the testing of theoretical models based on Social Cognitive Theory.

Error in telemetry studies: Effects of animal movement on triangulation

USGS Publications Warehouse

Schmutz, Joel A.; White, Gary C.

1990-01-01

We used Monte Carlo simulations to investigate the effects of animal movement on error of estimated animal locations derived from radio-telemetry triangulation of sequentially obtained bearings. Simulated movements of 0-534 m resulted in up to 10-fold increases in average location error but <10% decreases in location precision when observer-to-animal distances were <1,000 m. Location error and precision were minimally affected by censorship of poor locations with Chi-square goodness-of-fit tests. Location error caused by animal movement can only be eliminated by taking simultaneous bearings.

Chi-squared and C statistic minimization for low count per bin data

NASA Astrophysics Data System (ADS)

Nousek, John A.; Shue, David R.

1989-07-01

Results are presented from a computer simulation comparing two statistical fitting techniques on data samples with large and small counts per bin; the results are then related specifically to X-ray astronomy. The Marquardt and Powell minimization techniques are compared by using both to minimize the chi-squared statistic. In addition, Cash's C statistic is applied, with Powell's method, and it is shown that the C statistic produces better fits in the low-count regime than chi-squared.

Chi-squared and C statistic minimization for low count per bin data. [sampling in X ray astronomy

NASA Technical Reports Server (NTRS)

Nousek, John A.; Shue, David R.

1989-01-01

Results are presented from a computer simulation comparing two statistical fitting techniques on data samples with large and small counts per bin; the results are then related specifically to X-ray astronomy. The Marquardt and Powell minimization techniques are compared by using both to minimize the chi-squared statistic. In addition, Cash's C statistic is applied, with Powell's method, and it is shown that the C statistic produces better fits in the low-count regime than chi-squared.

Power and sensitivity of alternative fit indices in tests of measurement invariance.

PubMed

Meade, Adam W; Johnson, Emily C; Braddy, Phillip W

2008-05-01

Confirmatory factor analytic tests of measurement invariance (MI) based on the chi-square statistic are known to be highly sensitive to sample size. For this reason, G. W. Cheung and R. B. Rensvold (2002) recommended using alternative fit indices (AFIs) in MI investigations. In this article, the authors investigated the performance of AFIs with simulated data known to not be invariant. The results indicate that AFIs are much less sensitive to sample size and are more sensitive to a lack of invariance than chi-square-based tests of MI. The authors suggest reporting differences in comparative fit index (CFI) and R. P. McDonald's (1989) noncentrality index (NCI) to evaluate whether MI exists. Although a general value of change in CFI (.002) seemed to perform well in the analyses, condition specific change in McDonald's NCI values exhibited better performance than a single change in McDonald's NCI value. Tables of these values are provided as are recommendations for best practices in MI testing. PsycINFO Database Record (c) 2008 APA, all rights reserved.

Calibration power of the Braden scale in predicting pressure ulcer development.

PubMed

Chen, Hong-Lin; Cao, Ying-Juan; Wang, Jing; Huai, Bao-Sha

2016-11-02

Calibration is the degree of correspondence between the estimated probability produced by a model and the actual observed probability. The aim of this study was to investigate the calibration power of the Braden scale in predicting pressure ulcer development (PU). A retrospective analysis was performed among consecutive patients in 2013. The patients were separated into training a group and a validation group. The predicted incidence was calculated using a logistic regression model in the training group and the Hosmer-Lemeshow test was used for assessing the goodness of fit. In the validation cohort, the observed and the predicted incidence were compared by the Chi-square (χ 2 ) goodness of fit test for calibration power. We included 2585 patients in the study, of these 78 patients (3.0%) developed a PU. Between the training and validation groups the patient characteristics were non-significant (p>0.05). In the training group, the logistic regression model for predicting pressure ulcer was Logit(P) = -0.433*Braden score+2.616. The Hosmer-Lemeshow test showed no goodness fit (χ 2 =13.472; p=0.019). In the validation group, the predicted pressure ulcer incidence also did not fit well with the observed incidence (χ 2 =42.154, p=0.000 by Braden scores; and χ 2 =17.223, p=0.001 by Braden scale risk classification). The Braden scale has low calibration power in predicting PU formation.

Does Breast Cancer Drive the Building of Survival Probability Models among States? An Assessment of Goodness of Fit for Patient Data from SEER Registries

PubMed

Khan, Hafiz; Saxena, Anshul; Perisetti, Abhilash; Rafiq, Aamrin; Gabbidon, Kemesha; Mende, Sarah; Lyuksyutova, Maria; Quesada, Kandi; Blakely, Summre; Torres, Tiffany; Afesse, Mahlet

2016-12-01

Background: Breast cancer is a worldwide public health concern and is the most prevalent type of cancer in women in the United States. This study concerned the best fit of statistical probability models on the basis of survival times for nine state cancer registries: California, Connecticut, Georgia, Hawaii, Iowa, Michigan, New Mexico, Utah, and Washington. Materials and Methods: A probability random sampling method was applied to select and extract records of 2,000 breast cancer patients from the Surveillance Epidemiology and End Results (SEER) database for each of the nine state cancer registries used in this study. EasyFit software was utilized to identify the best probability models by using goodness of fit tests, and to estimate parameters for various statistical probability distributions that fit survival data. Results: Statistical analysis for the summary of statistics is reported for each of the states for the years 1973 to 2012. Kolmogorov-Smirnov, Anderson-Darling, and Chi-squared goodness of fit test values were used for survival data, the highest values of goodness of fit statistics being considered indicative of the best fit survival model for each state. Conclusions: It was found that California, Connecticut, Georgia, Iowa, New Mexico, and Washington followed the Burr probability distribution, while the Dagum probability distribution gave the best fit for Michigan and Utah, and Hawaii followed the Gamma probability distribution. These findings highlight differences between states through selected sociodemographic variables and also demonstrate probability modeling differences in breast cancer survival times. The results of this study can be used to guide healthcare providers and researchers for further investigations into social and environmental factors in order to reduce the occurrence of and mortality due to breast cancer. Creative Commons Attribution License

An evaluation of the structural validity of the shoulder pain and disability index (SPADI) using the Rasch model.

PubMed

Jerosch-Herold, Christina; Chester, Rachel; Shepstone, Lee; Vincent, Joshua I; MacDermid, Joy C

2018-02-01

The shoulder pain and disability index (SPADI) has been extensively evaluated for its psychometric properties using classical test theory (CTT). The purpose of this study was to evaluate its structural validity using Rasch model analysis. Responses to the SPADI from 1030 patients referred for physiotherapy with shoulder pain and enrolled in a prospective cohort study were available for Rasch model analysis. Overall fit, individual person and item fit, response format, dependence, unidimensionality, targeting, reliability and differential item functioning (DIF) were examined. The SPADI pain subscale initially demonstrated a misfit due to DIF by age and gender. After iterative analysis it showed good fit to the Rasch model with acceptable targeting and unidimensionality (overall fit Chi-square statistic 57.2, p = 0.1; mean item fit residual 0.19 (1.5) and mean person fit residual 0.44 (1.1); person separation index (PSI) of 0.83. The disability subscale however shows significant misfit due to uniform DIF even after iterative analyses were used to explore different solutions to the sources of misfit (overall fit (Chi-square statistic 57.2, p = 0.1); mean item fit residual 0.54 (1.26) and mean person fit residual 0.38 (1.0); PSI 0.84). Rasch Model analysis of the SPADI has identified some strengths and limitations not previously observed using CTT methods. The SPADI should be treated as two separate subscales. The SPADI is a widely used outcome measure in clinical practice and research; however, the scores derived from it must be interpreted with caution. The pain subscale fits the Rasch model expectations well. The disability subscale does not fit the Rasch model and its current format does not meet the criteria for true interval-level measurement required for use as a primary endpoint in clinical trials. Clinicians should therefore exercise caution when interpreting score changes on the disability subscale and attempt to compare their scores to age- and sex-stratified data.

Nuclear Matter Properties with the Re-evaluated Coefficients of Liquid Drop Model

NASA Astrophysics Data System (ADS)

Chowdhury, P. Roy; Basu, D. N.

2006-06-01

The coefficients of the volume, surface, Coulomb, asymmetry and pairing energy terms of the semiempirical liquid drop model mass formula have been determined by furnishing best fit to the observed mass excesses. Slightly different sets of the weighting parameters for liquid drop model mass formula have been obtained from minimizations of \\chi 2 and mean square deviation. The most recent experimental and estimated mass excesses from Audi-Wapstra-Thibault atomic mass table have been used for the least square fitting procedure. Equation of state, nuclear incompressibility, nuclear mean free path and the most stable nuclei for corresponding atomic numbers, all are in good agreement with the experimental results.

Applicability of action planning and coping planning to dental flossing among Norwegian adults: a confirmatory factor analysis approach.

PubMed

Astrøm, Anne Nordrehaug

2008-06-01

Using a prospective design and a representative sample of 25-yr-old Norwegians, this study hypothesized that action planning and coping planning will add to the prediction of flossing at 4 wk of follow-up over and above the effect of intention and previous flossing. This study tested the validity of a proposed 3-factor structure of the measurement model of intention, action planning, and coping planning and for its invariance across gender. A survey was conducted in three Norwegian counties, and 1,509 out of 8,000 randomly selected individuals completed questionnaires assessing the constructs of action planning and coping planning related to daily flossing. A random subsample of 500 participants was followed up at 4 wk with a telephone interview to assess flossing. Confirmatory factor analysis (CFA) confirmed the proposed 3-factor model after respecification. Although the chi-square test was statistically significant [chi(2) = 58.501, degrees of freedom (d.f.) = 17), complementary fit indices were satisfactory [goodness-of-fit index (GFI) = 0.99, root mean squared error of approximation (RMSEA) = 0.04]. Multigroup CFA provided evidence of complete invariance of the measurement model across gender. After controlling for previous flossing, intention (beta = 0.08) and action planning (beta = 0.11) emerged as independent predictors of subsequent flossing, accounting for 2.3% of its variance. Factorial validity of intention, action planning and coping planning, and the validity of action planning in predicting flossing prospectively, was confirmed by the present study.

Performance of Simplified Acute Physiology Score 3 In Predicting Hospital Mortality In Emergency Intensive Care Unit.

PubMed

Ma, Qing-Bian; Fu, Yuan-Wei; Feng, Lu; Zhai, Qiang-Rong; Liang, Yang; Wu, Meng; Zheng, Ya-An

2017-07-05

Since the 1980s, severity of illness scoring systems has gained increasing popularity in Intensive Care Units (ICUs). Physicians used them for predicting mortality and assessing illness severity in clinical trials. The objective of this study was to assess the performance of Simplified Acute Physiology Score 3 (SAPS 3) and its customized equation for Australasia (Australasia SAPS 3, SAPS 3 [AUS]) in predicting clinical prognosis and hospital mortality in emergency ICU (EICU). A retrospective analysis of the EICU including 463 patients was conducted between January 2013 and December 2015 in the EICU of Peking University Third Hospital. The worst physiological data of enrolled patients were collected within 24 h after admission to calculate SAPS 3 score and predicted mortality by regression equation. Discrimination between survivals and deaths was assessed by the area under the receiver operator characteristic curve (AUC). Calibration was evaluated by Hosmer-Lemeshow goodness-of-fit test through calculating the ratio of observed-to-expected numbers of deaths which is known as the standardized mortality ratio (SMR). A total of 463 patients were enrolled in the study, and the observed hospital mortality was 26.1% (121/463). The patients enrolled were divided into survivors and nonsurvivors. Age, SAPS 3 score, Acute Physiology and Chronic Health Evaluation Score II (APACHE II), and predicted mortality were significantly higher in nonsurvivors than survivors (P < 0.05 or P < 0.01). The AUC (95% confidence intervals [CI s]) for SAPS 3 score was 0.836 (0.796-0.876). The maximum of Youden's index, cutoff, sensitivity, and specificity of SAPS 3 score were 0.526%, 70.5 points, 66.9%, and 85.7%, respectively. The Hosmer-Lemeshow goodness-of-fit test for SAPS 3 demonstrated a Chi-square test score of 10.25, P = 0.33, SMR (95% CI) = 0.63 (0.52-0.76). The Hosmer-Lemeshow goodness-of-fit test for SAPS 3 (AUS) demonstrated a Chi-square test score of 9.55, P = 0.38, SMR (95% CI) = 0.68 (0.57-0.81). Univariate and multivariate analyses were conducted for biochemical variables that were probably correlated to prognosis. Eventually, blood urea nitrogen (BUN), albumin,lactate and free triiodothyronine (FT3) were selected as independent risk factors for predicting prognosis. The SAPS 3 score system exhibited satisfactory performance even superior to APACHE II in discrimination. In predicting hospital mortality, SAPS 3 did not exhibit good calibration and overestimated hospital mortality, which demonstrated that SAPS 3 needs improvement in the future.

Confirmatory Factor Analysis of the WHO Violence Against Women Instrument in Pregnant Women: Results from the BRISA Prenatal Cohort

PubMed Central

Ribeiro, Marizélia Rodrigues Costa; Alves, Maria Teresa Seabra Soares de Britto e.; Batista, Rosângela Fernandes Lucena; Ribeiro, Cecília Cláudia Costa; Schraiber, Lilia Blima; Barbieri, Marco Antônio; Bettiol, Heloisa; da Silva, Antônio Augusto Moura

2014-01-01

Background Screening for violence during pregnancy is one of the strategies for the prevention of abuse against women. Since violence is difficult to measure, it is necessary to validate questionnaires that can provide a good measure of the phenomenon. The present study analyzed the psychometric properties of the World Health Organization Violence Against Women (WHO VAW) instrument for the measurement of violence against pregnant women. Methods Data from the Brazilian Ribeirão Preto and São Luís birth cohort studies (BRISA) were used. The sample consisted of 1,446 pregnant women from São Luís and 1,378 from Ribeirão Preto, interviewed in 2010 and 2011. Thirteen variables were selected from a self-applied questionnaire. Confirmatory factor analysis was used to investigate whether violence is a uni-or-multidimensional construct consisting of psychological, physical and sexual dimensions. The mean-and-variance-adjusted weighted least squares estimator was used. Models were fitted separately for each city and a third model combining data from the two settings was also tested. Models suggested from modification indices were tested to determine whether changes in the WHO VAW model would produce a better fit. Results The unidimensional model did not show good fit (Root mean square error of approximation [RMSEA]  = 0.060, p<0.001 for the combined model). The multidimensional WHO VAW model showed good fit (RMSEA = 0.036, p = 0.999 for the combined model) and standardized factor loadings higher than 0.70, except for the sexual dimension for SL (0.65). The models suggested by the modification indices with cross loadings measuring simultaneously physical and psychological violence showed a significantly better fit compared to the original WHO model (p<0.001 for the difference between the model chi-squares). Conclusions Violence is a multidimensional second-order construct consisting of psychological, physical and sexual dimensions. The WHO VAW model and the modified models are suitable for measuring violence against pregnant women. PMID:25531654

Landslide susceptibility mapping using decision-tree based CHi-squared automatic interaction detection (CHAID) and Logistic regression (LR) integration

NASA Astrophysics Data System (ADS)

Althuwaynee, Omar F.; Pradhan, Biswajeet; Ahmad, Noordin

2014-06-01

This article uses methodology based on chi-squared automatic interaction detection (CHAID), as a multivariate method that has an automatic classification capacity to analyse large numbers of landslide conditioning factors. This new algorithm was developed to overcome the subjectivity of the manual categorization of scale data of landslide conditioning factors, and to predict rainfall-induced susceptibility map in Kuala Lumpur city and surrounding areas using geographic information system (GIS). The main objective of this article is to use CHi-squared automatic interaction detection (CHAID) method to perform the best classification fit for each conditioning factor, then, combining it with logistic regression (LR). LR model was used to find the corresponding coefficients of best fitting function that assess the optimal terminal nodes. A cluster pattern of landslide locations was extracted in previous study using nearest neighbor index (NNI), which were then used to identify the clustered landslide locations range. Clustered locations were used as model training data with 14 landslide conditioning factors such as; topographic derived parameters, lithology, NDVI, land use and land cover maps. Pearson chi-squared value was used to find the best classification fit between the dependent variable and conditioning factors. Finally the relationship between conditioning factors were assessed and the landslide susceptibility map (LSM) was produced. An area under the curve (AUC) was used to test the model reliability and prediction capability with the training and validation landslide locations respectively. This study proved the efficiency and reliability of decision tree (DT) model in landslide susceptibility mapping. Also it provided a valuable scientific basis for spatial decision making in planning and urban management studies.

Sample Size and Statistical Conclusions from Tests of Fit to the Rasch Model According to the Rasch Unidimensional Measurement Model (Rumm) Program in Health Outcome Measurement.

PubMed

Hagell, Peter; Westergren, Albert

Sample size is a major factor in statistical null hypothesis testing, which is the basis for many approaches to testing Rasch model fit. Few sample size recommendations for testing fit to the Rasch model concern the Rasch Unidimensional Measurement Models (RUMM) software, which features chi-square and ANOVA/F-ratio based fit statistics, including Bonferroni and algebraic sample size adjustments. This paper explores the occurrence of Type I errors with RUMM fit statistics, and the effects of algebraic sample size adjustments. Data with simulated Rasch model fitting 25-item dichotomous scales and sample sizes ranging from N = 50 to N = 2500 were analysed with and without algebraically adjusted sample sizes. Results suggest the occurrence of Type I errors with N less then or equal to 500, and that Bonferroni correction as well as downward algebraic sample size adjustment are useful to avoid such errors, whereas upward adjustment of smaller samples falsely signal misfit. Our observations suggest that sample sizes around N = 250 to N = 500 may provide a good balance for the statistical interpretation of the RUMM fit statistics studied here with respect to Type I errors and under the assumption of Rasch model fit within the examined frame of reference (i.e., about 25 item parameters well targeted to the sample).

A simple test of association for contingency tables with multiple column responses.

PubMed

Decady, Y J; Thomas, D R

2000-09-01

Loughin and Scherer (1998, Biometrics 54, 630-637) investigated tests of association in two-way tables when one of the categorical variables allows for multiple-category responses from individual respondents. Standard chi-squared tests are invalid in this case, and they developed a bootstrap test procedure that provides good control of test levels under the null hypothesis. This procedure and some others that have been proposed are computationally involved and are based on techniques that are relatively unfamiliar to many practitioners. In this paper, the methods introduced by Rao and Scott (1981, Journal of the American Statistical Association 76, 221-230) for analyzing complex survey data are used to develop a simple test based on a corrected chi-squared statistic.

The Thai version of the PSS-10: An Investigation of its psychometric properties.

PubMed

Wongpakaran, Nahathai; Wongpakaran, Tinakon

2010-06-12

Among the stress instruments that measure the degree to which life events are perceived as stressful, the Perceived Stress Scale (PSS) is widely used. The goal of this study was to examine the psychometric properties of a Thai version of the PSS-10 (T-PSS-10) with a clinical and non-clinical sample. Internal consistency, test-retest reliability, concurrent validity, and the factorial structure of the scale were tested. A total sample of 479 adult participants was recruited for the study: 368 medical students and 111 patients from two hospitals in Northern Thailand. The T-PSS-10 was used along with the Thai version of State Trait Anxiety Inventory (STAI), the Thai Version of the Rosenberg Self-Esteem Scale (RSES), and the Thai Depression Inventory (TDI). Exploratory Factor Analysis (EFA) yielded 2 factors with eigenvalues of 5.05 and 1.60, accounting for 66 percent of variance. Factor 1 consisted of 6 items representing "stress"; whereas Factor 2 consisted of 4 items representing "control". The item loadings ranged from 0.547 to 0.881. Investigation of the fit indices associated with Maximum Likelihood (ML) estimation revealed that the two-factor solution was adequate [chi2 = 35.035 (df = 26, N = 368, p < 0.111)]; Goodness-of-Fit Index (GFI) = 0.981; Root Mean Square Residual (RMR) = 0.022; Standardized Root Mean square Residual (SRMR) = 0.037, Comparative Fit Index (CFI) = 0.989; Normed Fit Index (NFI) = 0.96, Non-Normed Fit Index (NNFI) = 0.981, Root Mean Square Error of Approximation (RMSEA) = 0.031. It was found that the T-PSS-10 had a significant positive correlation with the STAI (r = 0.60, p < 0.0001), and the TDI (r = 0.55, p < 0.0001); and was significantly negatively correlated with the RSES (r = -0.46, p < 0.0001, N = 368). The overall Cronbach's alpha was 0.85. The ICC was 0.82 (95% CI, 0.72 and 0.88) at 4 week-retest reliability. The Thai version of the PSS-10 demonstrated excellent goodness-of-fit for the two factor solution model, as well as good reliability and validity for estimating the level of stress perception with a Thai population. Limitations of the study are discussed.

Wrong Answers on Multiple-Choice Achievement Tests: Blind Guesses or Systematic Choices?.

ERIC Educational Resources Information Center

Powell, J. C.

A multi-faceted model for the selection of answers for multiple-choice tests was developed from the findings of a series of exploratory studies. This model implies that answer selection should be curvilinear. A series of models were tested for fit using the chi square procedure. Data were collected from 359 elementary school students ages 9-12.…

Reliability growth modeling analysis of the space shuttle main engines based upon the Weibull process

NASA Technical Reports Server (NTRS)

Wheeler, J. T.

1990-01-01

The Weibull process, identified as the inhomogeneous Poisson process with the Weibull intensity function, is used to model the reliability growth assessment of the space shuttle main engine test and flight failure data. Additional tables of percentage-point probabilities for several different values of the confidence coefficient have been generated for setting (1-alpha)100-percent two sided confidence interval estimates on the mean time between failures. The tabled data pertain to two cases: (1) time-terminated testing, and (2) failure-terminated testing. The critical values of the three test statistics, namely Cramer-von Mises, Kolmogorov-Smirnov, and chi-square, were calculated and tabled for use in the goodness of fit tests for the engine reliability data. Numerical results are presented for five different groupings of the engine data that reflect the actual response to the failures.

Four-Dimensional Golden Search

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

Fenimore, Edward E.

2015-02-25

The Golden search technique is a method to search a multiple-dimension space to find the minimum. It basically subdivides the possible ranges of parameters until it brackets, to within an arbitrarily small distance, the minimum. It has the advantages that (1) the function to be minimized can be non-linear, (2) it does not require derivatives of the function, (3) the convergence criterion does not depend on the magnitude of the function. Thus, if the function is a goodness of fit parameter such as chi-square, the convergence does not depend on the noise being correctly estimated or the function correctly followingmore » the chi-square statistic. And, (4) the convergence criterion does not depend on the shape of the function. Thus, long shallow surfaces can be searched without the problem of premature convergence. As with many methods, the Golden search technique can be confused by surfaces with multiple minima.« less

Fitting a function to time-dependent ensemble averaged data.

PubMed

Fogelmark, Karl; Lomholt, Michael A; Irbäck, Anders; Ambjörnsson, Tobias

2018-05-03

Time-dependent ensemble averages, i.e., trajectory-based averages of some observable, are of importance in many fields of science. A crucial objective when interpreting such data is to fit these averages (for instance, squared displacements) with a function and extract parameters (such as diffusion constants). A commonly overlooked challenge in such function fitting procedures is that fluctuations around mean values, by construction, exhibit temporal correlations. We show that the only available general purpose function fitting methods, correlated chi-square method and the weighted least squares method (which neglects correlation), fail at either robust parameter estimation or accurate error estimation. We remedy this by deriving a new closed-form error estimation formula for weighted least square fitting. The new formula uses the full covariance matrix, i.e., rigorously includes temporal correlations, but is free of the robustness issues, inherent to the correlated chi-square method. We demonstrate its accuracy in four examples of importance in many fields: Brownian motion, damped harmonic oscillation, fractional Brownian motion and continuous time random walks. We also successfully apply our method, weighted least squares including correlation in error estimation (WLS-ICE), to particle tracking data. The WLS-ICE method is applicable to arbitrary fit functions, and we provide a publically available WLS-ICE software.

How-To-Do-It: Snails, Pill Bugs, Mealworms, and Chi-Square? Using Invertebrate Behavior to Illustrate Hypothesis Testing with Chi-Square.

ERIC Educational Resources Information Center

Biermann, Carol

1988-01-01

Described is a study designed to introduce students to the behavior of common invertebrate animals, and to use of the chi-square statistical technique. Discusses activities with snails, pill bugs, and mealworms. Provides an abbreviated chi-square table and instructions for performing the experiments and statistical tests. (CW)

Solar cell angle of incidence corrections

NASA Technical Reports Server (NTRS)

Burger, Dale R.; Mueller, Robert L.

1995-01-01

Literature on solar array angle of incidence corrections was found to be sparse and contained no tabular data for support. This lack along with recent data on 27 GaAs/Ge 4 cm by 4 cm cells initiated the analysis presented in this paper. The literature cites seven possible contributors to angle of incidence effects: cosine, optical front surface, edge, shadowing, UV degradation, particulate soiling, and background color. Only the first three are covered in this paper due to lack of sufficient data. The cosine correction is commonly used but is not sufficient when the incident angle is large. Fresnel reflection calculations require knowledge of the index of refraction of the coverglass front surface. The absolute index of refraction for the coverglass front surface was not known nor was it measured due to lack of funds. However, a value for the index of refraction was obtained by examining how the prediction errors varied with different assumed indices and selecting the best fit to the set of measured values. Corrections using front surface Fresnel reflection along with the cosine correction give very good predictive results when compared to measured data, except there is a definite trend away from predicted values at the larger incident angles. This trend could be related to edge effects and is illustrated by a use of a box plot of the errors and by plotting the deviation of the mean against incidence angle. The trend is for larger deviations at larger incidence angles and there may be a fourth order effect involved in the trend. A chi-squared test was used to determine if the measurement errors were normally distributed. At 10 degrees the chi-squared test failed, probably due to the very small numbers involved or a bias from the measurement procedure. All other angles showed a good fit to the normal distribution with increasing goodness-of-fit as the angles increased which reinforces the very small numbers hypothesis. The contributed data only went to 65 degrees from normal which prevented any firm conclusions about extreme angle effects although a trend in the right direction was seen. Measurement errors were estimated and found to be consistent with the conclusions that were drawn. A controlled experiment using coverglasses and cells from the same lots and extending to larger incidence angles would probably lead to further insight into the subject area.

An Evaluation of the Psychometric Properties of Three Different Forms of Daly and Miller's Writing Apprehension Test through Rasch Analysis

ERIC Educational Resources Information Center

Güler, Nese; Ilhan, Mustafa; Güneyli, Ahmet; Demir, Süleyman

2017-01-01

This study evaluates the psychometric properties of three different forms of the Writing Apprehension Test (WAT; Daly & Miller, 1975) through Rasch analysis. For this purpose, the fit statistics and correlation coefficients, and the reliability, separation ratio, and chi-square values for the facets of item and person calculated for the…

The Theory of Planned Behavior as a Model of Heavy Episodic Drinking Among College Students

PubMed Central

Collins, Susan E.; Carey, Kate B.

2008-01-01

This study provided a simultaneous, confirmatory test of the theory of planned behavior (TPB) in predicting heavy episodic drinking (HED) among college students. It was hypothesized that past HED, drinking attitudes, subjective norms and drinking refusal self-efficacy would predict intention, which would in turn predict future HED. Participants consisted of 131 college drinkers (63% female) who reported having engaged in HED in the previous two weeks. Participants were recruited and completed questionnaires within the context of a larger intervention study (see Collins & Carey, 2005). Latent factor structural equation modeling was used to test the ability of the TPB to predict HED. Chi-square tests and fit indices indicated good fit for the final structural models. Self-efficacy and attitudes but not subjective norms significantly predicted baseline intention, and intention and past HED predicted future HED. Contrary to hypotheses, however, a structural model excluding past HED provided a better fit than a model including it. Although further studies must be conducted before a definitive conclusion is reached, a TPB model excluding past behavior, which is arguably more parsimonious and theory driven, may provide better prediction of HED among college drinkers than a model including past behavior. PMID:18072832

Analyzing patient's waiting time in emergency & trauma department in public hospital - A case study

NASA Astrophysics Data System (ADS)

Roslan, Shazwa; Tahir, Herniza Md; Nordin, Noraimi Azlin Mohd; Zaharudin, Zati Aqmar

2014-09-01

Emergency and Trauma Department (ETD) is an important element for a hospital. It provides medical service, which operates 24 hours a day in most hospitals. However overcrowding is not exclusion for ETD. Overflowing occurs due to affordable services provided by public hospitals, since it is funded by the government. It is reported that a patient attending ETD must be treated within 90 minutes, in accordance to achieve the Key Performance Indicator (KPI). However, due to overcrowd situations, most patients have to wait longer than the KPI standard. In this paper, patient's average waiting time is analyzed. Using Chi-Square Test of Goodness, patient's inter arrival per hour is also investigated. As conclusion, Monday until Wednesday was identified as the days that exceed the KPI standard while Chi-Square Test of Goodness showed that the patient's inter arrival is independent and random.

Validation of the Brazilian version of the 'Spanish Burnout Inventory' in teachers.

PubMed

Gil-Monte, Pedro R; Carlotto, Mary Sandra; Câmara, Sheila Gonçalves

2010-02-01

To assess factorial validity and internal consistency of the Brazilian version of the 'Spanish Burnout Inventory' (SBI). The translation process of the SBI into Brazilian Portuguese included translation, back translation, and semantic equivalence. A confirmatory factor analysis was carried out using a four-factor model, which was similar to the original SBI. The sample consisted of 714 teachers working in schools in the metropolitan area of the city of Porto Alegre, Southern Brazil, in 2008. The instrument comprises 20 items and four subscales: Enthusiasm towards job (5 items), Psychological exhaustion (4 items), Indolence (6 items), and Guilt (5 items). The model was analyzed using LISREL 8. Goodness-of-Fit statistics showed that the hypothesized model had adequate fit: chi2(164) = 605.86 (p<0.000); Goodness-of-Fit Index = 0.92; Adjusted Goodness-of-Fit Index = 0.90; Root Mean Square Error of Approximation = 0.062; Nonnormed Fit Index = 0.91; Comparative Fit Index = 0.92; and Parsimony Normed Fit Index = 0.77. Cronbach's alpha measures for all subscales were higher than 0.70. The study showed that the SBI has adequate factorial validity and internal consistency to assess burnout in Brazilian teachers.

Calorie-labelling in catering outlets: acceptability and impacts on food sales.

PubMed

Nikolaou, Charoula K; Lean, Michael E J; Hankey, Catherine R

2014-10-01

Obesity is the biggest challenge facing preventive medicine. Calorie-labelling has been suggested as a way of changing the architecture of an 'obesogenic' environment without limiting consumer choice. This study examined the effect of calorie-labelling on sales of food items at catering outlets on a city-centre university campus. Sales data were collected for two consecutive months in 2013 on three UK university sites (two with calorie-labelling during second month, one control) and analysed with chi-square 'Goodness-of-Fit' tests. A questionnaire seeking consumers' views and use of the calorie-labelling was administered and analysed at group-level with chi-square tests. In intervention vs control sites, total sales of all labelled items fell significantly (-17% vs -2%, p<0.001) for the month with calorie-labelling. Calorie-labelling was associated with substantially reduced sales of high-calorie labelled items, without any compensatory changes in unlabelled alternative items. Among 1166 student- and 646 staff-respondents, 56% reported using the calorie-labels, 97% of them to make lower-calorie choices. More females (63%) than males (40%) reported being influenced by calorie-labels when choosing foods (p=0.01). This study provides evidence, beyond that from single-meal exposures, for the acceptability of meal calorie-labelling and its potential as an effective low-cost anti-obesity measure. Copyright © 2014 Elsevier Inc. All rights reserved.

A structural equation model of perceived and internalized stigma, depression, and suicidal status among people living with HIV/AIDS.

PubMed

Zeng, Chengbo; Li, Linghua; Hong, Yan Alicia; Zhang, Hanxi; Babbitt, Andrew Walker; Liu, Cong; Li, Lixia; Qiao, Jiaying; Guo, Yan; Cai, Weiping

2018-01-15

Previous studies have shown positive association between HIV-related stigma and depression, suicidal ideation, and suicidal attempt among people living with HIV/AIDS (PLWH). But few studies have examined the mechanisms among HIV-related stigma, depression, and suicidal status (suicidal ideation and/or suicidal attempt) in PLWH. The current study examined the relationships among perceived and internalized stigma (PIS), depression, and suicidal status among PLWH in Guangzhou, China using structural equation modeling. Cross-sectional study by convenience sampling was conducted and 411 PLWH were recruited from the Number Eight People's Hospital from March to June, 2013 in Guangzhou, China. Participants were interviewed on their PIS, depressive symptoms, suicidal status, and socio-demographic characteristics. PLWH who had had suicidal ideation and suicidal attempts since HIV diagnosis were considered to be suicidal. Structural equation model was performed to examine the direct and indirect associations of PIS and suicidal status. Indicators to evaluate goodness of fit of the structural equation model included Chi-square Statistic, Comparative Fit Index (CFI), Root Mean Square Error of Approximation (RMSEA), Standardized Root Mean Square Residual (SRMR), and Weighted Root Mean Square Residual (WRMR). More than one-third (38.4%) of the PLWH had depressive symptoms and 32.4% reported suicidal ideation and/or attempt since HIV diagnosis. The global model showed good model fit (Chi-square value = 34.42, CFI = 0.98, RMSEA = 0.03, WRMR = 0.73). Structural equation model revealed that direct pathway of PIS on suicidal status was significant (standardized pathway coefficient = 0.21), and indirect pathway of PIS on suicidal status via depression was also significant (standardized pathway coefficient = 0.24). There was a partial mediating effect of depression in the association between PIS and suicidal status. Our findings suggest that PIS is associated with increased depression and the likelihood of suicidal status. Depression is in turn positively associated with suicidal status and plays a mediating role between PIS and suicidal status. Therefore, to reduce suicidal ideation and attempt in PLWH, targeted interventions to reduce PIS and improve mental health status of PLWH are warranted.

Your Chi-Square Test Is Statistically Significant: Now What?

ERIC Educational Resources Information Center

Sharpe, Donald

2015-01-01

Applied researchers have employed chi-square tests for more than one hundred years. This paper addresses the question of how one should follow a statistically significant chi-square test result in order to determine the source of that result. Four approaches were evaluated: calculating residuals, comparing cells, ransacking, and partitioning. Data…

A revisit to contingency table and tests of independence: bootstrap is preferred to Chi-square approximations as well as Fisher's exact test.

PubMed

Lin, Jyh-Jiuan; Chang, Ching-Hui; Pal, Nabendu

2015-01-01

To test the mutual independence of two qualitative variables (or attributes), it is a common practice to follow the Chi-square tests (Pearson's as well as likelihood ratio test) based on data in the form of a contingency table. However, it should be noted that these popular Chi-square tests are asymptotic in nature and are useful when the cell frequencies are "not too small." In this article, we explore the accuracy of the Chi-square tests through an extensive simulation study and then propose their bootstrap versions that appear to work better than the asymptotic Chi-square tests. The bootstrap tests are useful even for small-cell frequencies as they maintain the nominal level quite accurately. Also, the proposed bootstrap tests are more convenient than the Fisher's exact test which is often criticized for being too conservative. Finally, all test methods are applied to a few real-life datasets for demonstration purposes.

A goodness-of-fit test for occupancy models with correlated within-season revisits

USGS Publications Warehouse

Wright, Wilson; Irvine, Kathryn M.; Rodhouse, Thomas J.

2016-01-01

Occupancy modeling is important for exploring species distribution patterns and for conservation monitoring. Within this framework, explicit attention is given to species detection probabilities estimated from replicate surveys to sample units. A central assumption is that replicate surveys are independent Bernoulli trials, but this assumption becomes untenable when ecologists serially deploy remote cameras and acoustic recording devices over days and weeks to survey rare and elusive animals. Proposed solutions involve modifying the detection-level component of the model (e.g., first-order Markov covariate). Evaluating whether a model sufficiently accounts for correlation is imperative, but clear guidance for practitioners is lacking. Currently, an omnibus goodnessof- fit test using a chi-square discrepancy measure on unique detection histories is available for occupancy models (MacKenzie and Bailey, Journal of Agricultural, Biological, and Environmental Statistics, 9, 2004, 300; hereafter, MacKenzie– Bailey test). We propose a join count summary measure adapted from spatial statistics to directly assess correlation after fitting a model. We motivate our work with a dataset of multinight bat call recordings from a pilot study for the North American Bat Monitoring Program. We found in simulations that our join count test was more reliable than the MacKenzie–Bailey test for detecting inadequacy of a model that assumed independence, particularly when serial correlation was low to moderate. A model that included a Markov-structured detection-level covariate produced unbiased occupancy estimates except in the presence of strong serial correlation and a revisit design consisting only of temporal replicates. When applied to two common bat species, our approach illustrates that sophisticated models do not guarantee adequate fit to real data, underscoring the importance of model assessment. Our join count test provides a widely applicable goodness-of-fit test and specifically evaluates occupancy model lack of fit related to correlation among detections within a sample unit. Our diagnostic tool is available for practitioners that serially deploy survey equipment as a way to achieve cost savings.

Factor structure and psychometric properties of the english version of the trier inventory for chronic stress (TICS-E).

PubMed

Petrowski, Katja; Kliem, Sören; Sadler, Michael; Meuret, Alicia E; Ritz, Thomas; Brähler, Elmar

2018-02-06

Demands placed on individuals in occupational and social settings, as well as imbalances in personal traits and resources, can lead to chronic stress. The Trier Inventory for Chronic Stress (TICS) measures chronic stress while incorporating domain-specific aspects, and has been found to be a highly reliable and valid research tool. The aims of the present study were to confirm the German version TICS factorial structure in an English translation of the instrument (TICS-E) and to report its psychometric properties. A random route sample of healthy participants (N = 483) aged 18-30 years completed the TICS-E. The robust maximum likelihood estimation with a mean-adjusted chi-square test statistic was applied due to the sample's significant deviation from the multivariate normal distribution. Goodness of fit, absolute model fit, and relative model fit were assessed by means of the root mean square error of approximation (RMSEA), the Comparative Fit Index (CFI) and the Tucker Lewis Index (TLI). Reliability estimates (Cronbach's α and adjusted split-half reliability) ranged from .84 to .92. Item-scale correlations ranged from .50 to .85. Measures of fit showed values of .052 for RMSEA (Cl = 0.50-.054) and .067 for SRMR for absolute model fit, and values of .846 (TLI) and .855 (CFI) for relative model-fit. Factor loadings ranged from .55 to .91. The psychometric properties and factor structure of the TICS-E are comparable to the German version of the TICS. The instrument therefore meets quality standards for an adequate measurement of chronic stress.

Leader empowering behaviours, staff nurse empowerment and work engagement/burnout.

PubMed

Greco, Paula; Laschinger, Heather K Spence; Wong, Carol

2006-12-01

Efforts to improve nursing working conditions are critical to retaining nurses currently in the system and attracting newcomers to the profession (Laschinger et al. 2003b). The nurse leader's empowering behaviours can be pivotal in the way nurses react to their work environment. The purpose of this study was to test a model examining the relationship between nurse leaders' empowerment behaviours, perceptions of staff empowerment, areas of work life and work engagement using Kanter's theory of structural power in organizations. A cross-sectional correlational survey design tested the model in a random sample of 322 staff nurses in acute care hospitals across Ontario. Overall, staff nurses perceived their leaders' behaviours to be somewhat empowering and their work environment to be moderately empowering. Fifty-three percent reported severe levels of burnout. Leader empowering behaviour had an indirect effect on emotional exhaustion (burnout) through structural empowerment and overall fit in the six areas of work life. The final model statistics revealed a good fit (chi(2)=30.4, chi=3, chi=0.96, chi=0.95, chi=0.95). These findings suggest that the Leader's empowering behaviours can enhance person-job fit and prevent burnout. These findings have important implications in the current nursing shortage.

Estimation and prediction of maximum daily rainfall at Sagar Island using best fit probability models

NASA Astrophysics Data System (ADS)

Mandal, S.; Choudhury, B. U.

2015-07-01

Sagar Island, setting on the continental shelf of Bay of Bengal, is one of the most vulnerable deltas to the occurrence of extreme rainfall-driven climatic hazards. Information on probability of occurrence of maximum daily rainfall will be useful in devising risk management for sustaining rainfed agrarian economy vis-a-vis food and livelihood security. Using six probability distribution models and long-term (1982-2010) daily rainfall data, we studied the probability of occurrence of annual, seasonal and monthly maximum daily rainfall (MDR) in the island. To select the best fit distribution models for annual, seasonal and monthly time series based on maximum rank with minimum value of test statistics, three statistical goodness of fit tests, viz. Kolmogorove-Smirnov test (K-S), Anderson Darling test ( A 2 ) and Chi-Square test ( X 2) were employed. The fourth probability distribution was identified from the highest overall score obtained from the three goodness of fit tests. Results revealed that normal probability distribution was best fitted for annual, post-monsoon and summer seasons MDR, while Lognormal, Weibull and Pearson 5 were best fitted for pre-monsoon, monsoon and winter seasons, respectively. The estimated annual MDR were 50, 69, 86, 106 and 114 mm for return periods of 2, 5, 10, 20 and 25 years, respectively. The probability of getting an annual MDR of >50, >100, >150, >200 and >250 mm were estimated as 99, 85, 40, 12 and 03 % level of exceedance, respectively. The monsoon, summer and winter seasons exhibited comparatively higher probabilities (78 to 85 %) for MDR of >100 mm and moderate probabilities (37 to 46 %) for >150 mm. For different recurrence intervals, the percent probability of MDR varied widely across intra- and inter-annual periods. In the island, rainfall anomaly can pose a climatic threat to the sustainability of agricultural production and thus needs adequate adaptation and mitigation measures.

Conceptual Model on Application of Chi-Square Test in Education and Social Sciences

ERIC Educational Resources Information Center

Onchiri, Sureiman

2013-01-01

Whenever you think you have an idea of how something works, you have a mental model. That is, in effect, a layman's way of talking about having an hypothesis. The hypothesis needs to be tested for how closely it fits reality--and reality is the data collected from an experiment. So the data is collected on the few and compared with a few…

Reconnaissance On Chi-Square Test Procedure For Determining Two Species Association

NASA Astrophysics Data System (ADS)

Marisa, Hanifa

2008-01-01

Determining the assosiation of two species by using chi-square test has been published. Utility of this procedure to plants species at certain location, shows that the procedure could not find "ecologically" association. Tens sampling units have been made to record some weeds species in Indralaya, South Sumatera. Chi square test; Xt2 = N[|(ad)-(bc)|-(N/2)]2/mnrs (Eq:1) on two species (Cleome sp and Eleusine indica) of the weeds shows positive assosiation; while ecologically in nature, there is no relationship between them. Some alternatives are proposed to this problem; simplified chi-square test steps, make further study to find out ecologically association, or at last, ignore it.

Chi-square-based scoring function for categorization of MEDLINE citations.

PubMed

Kastrin, A; Peterlin, B; Hristovski, D

2010-01-01

Text categorization has been used in biomedical informatics for identifying documents containing relevant topics of interest. We developed a simple method that uses a chi-square-based scoring function to determine the likelihood of MEDLINE citations containing genetic relevant topic. Our procedure requires construction of a genetic and a nongenetic domain document corpus. We used MeSH descriptors assigned to MEDLINE citations for this categorization task. We compared frequencies of MeSH descriptors between two corpora applying chi-square test. A MeSH descriptor was considered to be a positive indicator if its relative observed frequency in the genetic domain corpus was greater than its relative observed frequency in the nongenetic domain corpus. The output of the proposed method is a list of scores for all the citations, with the highest score given to those citations containing MeSH descriptors typical for the genetic domain. Validation was done on a set of 734 manually annotated MEDLINE citations. It achieved predictive accuracy of 0.87 with 0.69 recall and 0.64 precision. We evaluated the method by comparing it to three machine-learning algorithms (support vector machines, decision trees, naïve Bayes). Although the differences were not statistically significantly different, results showed that our chi-square scoring performs as good as compared machine-learning algorithms. We suggest that the chi-square scoring is an effective solution to help categorize MEDLINE citations. The algorithm is implemented in the BITOLA literature-based discovery support system as a preprocessor for gene symbol disambiguation process.

Assessment of performance and utility of mortality prediction models in a single Indian mixed tertiary intensive care unit.

PubMed

Sathe, Prachee M; Bapat, Sharda N

2014-01-01

To assess the performance and utility of two mortality prediction models viz. Acute Physiology and Chronic Health Evaluation II (APACHE II) and Simplified Acute Physiology Score II (SAPS II) in a single Indian mixed tertiary intensive care unit (ICU). Secondary objectives were bench-marking and setting a base line for research. In this observational cohort, data needed for calculation of both scores were prospectively collected for all consecutive admissions to 28-bedded ICU in the year 2011. After excluding readmissions, discharges within 24 h and age <18 years, the records of 1543 patients were analyzed using appropriate statistical methods. Both models overpredicted mortality in this cohort [standardized mortality ratio (SMR) 0.88 ± 0.05 and 0.95 ± 0.06 using APACHE II and SAPS II respectively]. Patterns of predicted mortality had strong association with true mortality (R (2) = 0.98 for APACHE II and R (2) = 0.99 for SAPS II). Both models performed poorly in formal Hosmer-Lemeshow goodness-of-fit testing (Chi-square = 12.8 (P = 0.03) for APACHE II, Chi-square = 26.6 (P = 0.001) for SAPS II) but showed good discrimination (area under receiver operating characteristic curve 0.86 ± 0.013 SE (P < 0.001) and 0.83 ± 0.013 SE (P < 0.001) for APACHE II and SAPS II, respectively). There were wide variations in SMRs calculated for subgroups based on International Classification of Disease, 10(th) edition (standard deviation ± 0.27 for APACHE II and 0.30 for SAPS II). Lack of fit of data to the models and wide variation in SMRs in subgroups put a limitation on utility of these models as tools for assessing quality of care and comparing performances of different units without customization. Considering comparable performance and simplicity of use, efforts should be made to adapt SAPS II.

Some applications of categorical data analysis to epidemiological studies.

PubMed Central

Grizzle, J E; Koch, G G

1979-01-01

Several examples of categorized data from epidemiological studies are analyzed to illustrate that more informative analysis than tests of independence can be performed by fitting models. All of the analyses fit into a unified conceptual framework that can be performed by weighted least squares. The methods presented show how to calculate point estimate of parameters, asymptotic variances, and asymptotically valid chi 2 tests. The examples presented are analysis of relative risks estimated from several 2 x 2 tables, analysis of selected features of life tables, construction of synthetic life tables from cross-sectional studies, and analysis of dose-response curves. PMID:540590

Statistical analysis of NaOH pretreatment effects on sweet sorghum bagasse characteristics

NASA Astrophysics Data System (ADS)

Putri, Ary Mauliva Hada; Wahyuni, Eka Tri; Sudiyani, Yanni

2017-01-01

We analyze the behavior of sweet sorghum bagasse characteristics before and after NaOH pretreatments by statistical analysis. These characteristics include the percentages of lignocellulosic materials and the degree of crystallinity. We use the chi-square method to get the values of fitted parameters, and then deploy student's t-test to check whether they are significantly different from zero at 99.73% confidence level (C.L.). We obtain, in the cases of hemicellulose and lignin, that their percentages after pretreatment decrease statistically. On the other hand, crystallinity does not possess similar behavior as the data proves that all fitted parameters in this case might be consistent with zero. Our statistical result is then cross examined with the observations from X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) Spectroscopy, showing pretty good agreement. This result may indicate that the 10% NaOH pretreatment might not be sufficient in changing the crystallinity index of the sweet sorghum bagasse.

Coronal temperatures of unusually active K-dwarf binary systems

NASA Technical Reports Server (NTRS)

Stern, Robert A.

1994-01-01

We report the results of a ROSAT pointed study of 4 BY Dra systems. Good quality pulse-height spectra are available from all four systems. Except for a required interstellar absorption component in HD 319139, the four systems have remarkably similar x-ray spectra; the two systems BD +22deg.669 and BD +23deg.635 look virtually identical in x rays. Analysis of the 4 x-ray spectra reveals that, in all cases, a single-temperature hot plasma (RS or Mewe) spectra is inadequate to fit the data, and two temperatures are required. We present examples of fitted pulse-height spectra and chi squared contours in kT(sub 1)-kT(sub 2) space.

Using latent class analysis to model prescription medications in the measurement of falling among a community elderly population

PubMed Central

2013-01-01

Background Falls among the elderly are a major public health concern. Therefore, the possibility of a modeling technique which could better estimate fall probability is both timely and needed. Using biomedical, pharmacological and demographic variables as predictors, latent class analysis (LCA) is demonstrated as a tool for the prediction of falls among community dwelling elderly. Methods Using a retrospective data-set a two-step LCA modeling approach was employed. First, we looked for the optimal number of latent classes for the seven medical indicators, along with the patients’ prescription medication and three covariates (age, gender, and number of medications). Second, the appropriate latent class structure, with the covariates, were modeled on the distal outcome (fall/no fall). The default estimator was maximum likelihood with robust standard errors. The Pearson chi-square, likelihood ratio chi-square, BIC, Lo-Mendell-Rubin Adjusted Likelihood Ratio test and the bootstrap likelihood ratio test were used for model comparisons. Results A review of the model fit indices with covariates shows that a six-class solution was preferred. The predictive probability for latent classes ranged from 84% to 97%. Entropy, a measure of classification accuracy, was good at 90%. Specific prescription medications were found to strongly influence group membership. Conclusions In conclusion the LCA method was effective at finding relevant subgroups within a heterogenous at-risk population for falling. This study demonstrated that LCA offers researchers a valuable tool to model medical data. PMID:23705639

Caregiving for Parkinson's disease patients: an exploration of a stress-appraisal model for quality of life and burden.

PubMed

Goldsworthy, Belinda; Knowles, Simon

2008-11-01

Extending the 2002 stress-appraisal model of Chappell and Reid, we examined the relationships between caregiver stressors (e.g., cognitive impairment and functional dependency of the recipient), appraisal (informal hours of caregiving), and protective factors (e.g., social support, self-esteem, and quality of the caregiver-recipient relationship) associated with the burden and quality of life of Parkinson's disease caregivers. There were 136 caregivers (M = 64.59 years) who completed an online survey. Using structural equation modeling, we found that the extended stress-appraisal model of Chappell and Reid provided a good fit to the data (chi2 = 67.87, df = 55, p >.05; chi2/df = 1.23, Comparative Fit Index = 0.98, Root Mean Square Error of Approximation = 0.04). This study provides an important contribution to a growing field of research that applies theoretical models to investigate the stressors, appraisals, and protective factors that impact caregiver well-being.

Evaluation of the Edinburgh Post Natal Depression Scale using Rasch analysis

PubMed Central

Pallant, Julie F; Miller, Renée L; Tennant, Alan

2006-01-01

Background The Edinburgh Postnatal Depression Scale (EPDS) is a 10 item self-rating post-natal depression scale which has seen widespread use in epidemiological and clinical studies. Concern has been raised over the validity of the EPDS as a single summed scale, with suggestions that it measures two separate aspects, one of depressive feelings, the other of anxiety. Methods As part of a larger cross-sectional study conducted in Melbourne, Australia, a community sample (324 women, ranging in age from 18 to 44 years: mean = 32 yrs, SD = 4.6), was obtained by inviting primiparous women to participate voluntarily in this study. Data from the EPDS were fitted to the Rasch measurement model and tested for appropriate category ordering, for item bias through Differential Item Functioning (DIF) analysis, and for unidimensionality through tests of the assumption of local independence. Results Rasch analysis of the data from the ten item scale initially demonstrated a lack of fit to the model with a significant Item-Trait Interaction total chi-square (chi Square = 82.8, df = 40; p < .001). Removal of two items (items 7 and 8) resulted in a non-significant Item-Trait Interaction total chi-square with a residual mean value for items of -0.467 with a standard deviation of 0.850, showing fit to the model. No DIF existed in the final 8-item scale (EPDS-8) and all items showed fit to model expectations. Principal Components Analysis of the residuals supported the local independence assumption, and unidimensionality of the revised EPDS-8 scale. Revised cut points were identified for EPDS-8 to maintain the case identification of the original scale. Conclusion The results of this study suggest that EPDS, in its original 10 item form, is not a viable scale for the unidimensional measurement of depression. Rasch analysis suggests that a revised eight item version (EPDS-8) would provide a more psychometrically robust scale. The revised cut points of 7/8 and 9/10 for the EPDS-8 show high levels of agreement with the original case identification for the EPDS-10. PMID:16768803

How motivation affects academic performance: a structural equation modelling analysis.

PubMed

Kusurkar, R A; Ten Cate, Th J; Vos, C M P; Westers, P; Croiset, G

2013-03-01

Few studies in medical education have studied effect of quality of motivation on performance. Self-Determination Theory based on quality of motivation differentiates between Autonomous Motivation (AM) that originates within an individual and Controlled Motivation (CM) that originates from external sources. To determine whether Relative Autonomous Motivation (RAM, a measure of the balance between AM and CM) affects academic performance through good study strategy and higher study effort and compare this model between subgroups: males and females; students selected via two different systems namely qualitative and weighted lottery selection. Data on motivation, study strategy and effort was collected from 383 medical students of VU University Medical Center Amsterdam and their academic performance results were obtained from the student administration. Structural Equation Modelling analysis technique was used to test a hypothesized model in which high RAM would positively affect Good Study Strategy (GSS) and study effort, which in turn would positively affect academic performance in the form of grade point averages. This model fit well with the data, Chi square = 1.095, df = 3, p = 0.778, RMSEA model fit = 0.000. This model also fitted well for all tested subgroups of students. Differences were found in the strength of relationships between the variables for the different subgroups as expected. In conclusion, RAM positively correlated with academic performance through deep strategy towards study and higher study effort. This model seems valid in medical education in subgroups such as males, females, students selected by qualitative and weighted lottery selection.

Detecting Non-Gaussian and Lognormal Characteristics of Temperature and Water Vapor Mixing Ratio

NASA Astrophysics Data System (ADS)

Kliewer, A.; Fletcher, S. J.; Jones, A. S.; Forsythe, J. M.

2017-12-01

Many operational data assimilation and retrieval systems assume that the errors and variables come from a Gaussian distribution. This study builds upon previous results that shows that positive definite variables, specifically water vapor mixing ratio and temperature, can follow a non-Gaussian distribution and moreover a lognormal distribution. Previously, statistical testing procedures which included the Jarque-Bera test, the Shapiro-Wilk test, the Chi-squared goodness-of-fit test, and a composite test which incorporated the results of the former tests were employed to determine locations and time spans where atmospheric variables assume a non-Gaussian distribution. These tests are now investigated in a "sliding window" fashion in order to extend the testing procedure to near real-time. The analyzed 1-degree resolution data comes from the National Oceanic and Atmospheric Administration (NOAA) Global Forecast System (GFS) six hour forecast from the 0Z analysis. These results indicate the necessity of a Data Assimilation (DA) system to be able to properly use the lognormally-distributed variables in an appropriate Bayesian analysis that does not assume the variables are Gaussian.

The parental monitoring of diabetes care scale: development, reliability and validity of a scale to evaluate parental supervision of adolescent illness management.

PubMed

Ellis, Deborah A; Templin, Thomas N; Podolski, Cheryl-Lynn; Frey, Maureen A; Naar-King, Sylvie; Moltz, Kathleen

2008-02-01

Monitoring of adolescents' behavior and whereabouts has been repeatedly identified as an important predictor of adolescent behavioral outcomes. However, to date, measures of parental supervision and monitoring are lacking in the chronic illness literature. The present study describes development and initial evaluation of a measure of parental monitoring of the illness management of adolescents with diabetes: the Parental Monitoring of Diabetes Care scale (PMDC). Ninety-nine parents of 12-18-year-old children with type 1 diabetes completed the PMDC. Measures of illness management and metabolic control were also obtained. The PMDC demonstrated good internal consistency (alpha coefficient = .81) and test-rest reliability (ICC = .80). Supporting the instrument's construct validity, confirmatory factor analysis indicated that a five subdomain structure had an acceptable fit to the data, [chi(2) (181.65)/df (126) = 1.44, Bollen-Stine chi(2) = 165.03, p = .32, comparative fit index (CFI) = .91, and root-mean-square error of approximation = .07]. In structural equation models, parental monitoring as assessed by the PMDC had a significant direct effect on adolescent diabetes management, accounting for 38% of the variance. Parental monitoring also had a significant indirect effect on metabolic control. The PMDC represents an important first step in the development of measures of parental monitoring for use with adolescents with chronic medical conditions.

IUE observations of the Jovian dayglow emission

NASA Technical Reports Server (NTRS)

Mcgrath, M. A.; Feldman, P. D.; Ballester, G. E.; Moos, H. W.

1989-01-01

IUE spectra of Jupiter are examined in light of recent models put forward to explain the anomalously bright ultraviolet emissions seen from the upper atmospheres of the outer planets. Chi-squared fits of the IUE spectra with model spectra produced by two proposed excitation mechanisms, electron impact and fluorescence of solar radiation, result in consistently higher chi-squared values for the solar fluorescence model. No conclusive evidence is found in the IUE data for the dominance of solar fluorescence over electron excitation in producing the Jovian dayglow emission.

Italian version of the Task and Ego Orientation in physical education questionnaire.

PubMed

Bortoli, Laura; Robazza, Claudio

2005-12-01

The 1992 Task and Ego Orientation in Sport Questionnaire developed by Duda and Nicholls was modified by Walling and Duda in 1995 to assess task and ego orientation in physical education. The modified version was translated into Italian and administered to 1,547 students, 786 girls and 761 boys ages 14 to 19 years, to examine the factor structure. To evaluate the goodness of fit of the expected two-factor solution as in the original questionnaire, confirmatory factor analysis was conducted on four samples of boys and girls of two classes of age (14-16 and 17-19 years). Across sex and age, chi-squared/df ratios were less than 5.0, fit indices (GFI, NNFI, and CFI) not less than .90, and root mean square error of approximation (RMSEA) below .10. Thus, the two-factor solution of the questionnaire was supported. In the total sample, the two scales showed good internal consistency, with Cronbach alpha values of .92 for the Ego factor and .83 for the Task factor. The Ego factor accounted for 34.1% of variance and the Task factor accounted for 21.0% of variance.

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.

A Comparison of Lord's Chi Square and Raju's Area Measures in Detection of DIF.

ERIC Educational Resources Information Center

Cohen, Allan S.; Kim, Seock-Ho

1993-01-01

The effectiveness of two statistical tests of the area between item response functions (exact signed area and exact unsigned area) estimated in different samples, a measure of differential item functioning (DIF), was compared with Lord's chi square. Lord's chi square was found the most effective in determining DIF. (SLD)

Residual depressive symptoms, sleep disturbance and perceived cognitive impairment as determinants of functioning in patients with bipolar disorder.

PubMed

Samalin, Ludovic; Boyer, Laurent; Murru, Andrea; Pacchiarotti, Isabella; Reinares, María; Bonnin, Caterina Mar; Torrent, Carla; Verdolini, Norma; Pancheri, Corinna; de Chazeron, Ingrid; Boucekine, Mohamed; Geoffroy, Pierre-Alexis; Bellivier, Frank; Llorca, Pierre-Michel; Vieta, Eduard

2017-03-01

Many patients with bipolar disorder (BD) experience residual symptoms during their inter-episodic periods. The study aimed to analyse the relationship between residual depressive symptoms, sleep disturbances and self-reported cognitive impairment as determinants of psychosocial functioning in a large sample of euthymic BD patients. This was a cross-sectional study of 468 euthymic BD outpatients. We evaluated the residual depressive symptoms with the Bipolar Depression Rating Scale, the sleep disturbances with the Pittsburgh Sleep Quality Index, the perceived cognitive performance using visual analogic scales and functioning with the Functioning Assessment Short Test. Structural equation modelling (SEM) was used to describe the relationships among the residual depressive symptoms, sleep disturbances, perceived cognitive performance and functioning. SEM showed good fit with normed chi square=2.46, comparative fit index=0.94, root mean square error of approximation=0.05 and standardized root mean square residuals=0.06. This model revealed that residual depressive symptoms (path coefficient =0.37) and perceived cognitive performance (path coefficient=0.27) were the most important features significantly related to psychosocial functioning. Sleep disturbances were indirectly associated with functioning via residual depressive symptoms and perceived cognitive performance (path coefficient=0.23). This study contributes to a better understanding of the determinants of psychosocial functioning during the inter-episodic periods of BD patients. These findings should facilitate decision-making in therapeutics to improve the functional outcomes of BD during this period. Copyright © 2017 Elsevier B.V. All rights reserved.

Uncertainties in extracted parameters of a Gaussian emission line profile with continuum background.

PubMed

Minin, Serge; Kamalabadi, Farzad

2009-12-20

We derive analytical equations for uncertainties in parameters extracted by nonlinear least-squares fitting of a Gaussian emission function with an unknown continuum background component in the presence of additive white Gaussian noise. The derivation is based on the inversion of the full curvature matrix (equivalent to Fisher information matrix) of the least-squares error, chi(2), in a four-variable fitting parameter space. The derived uncertainty formulas (equivalent to Cramer-Rao error bounds) are found to be in good agreement with the numerically computed uncertainties from a large ensemble of simulated measurements. The derived formulas can be used for estimating minimum achievable errors for a given signal-to-noise ratio and for investigating some aspects of measurement setup trade-offs and optimization. While the intended application is Fabry-Perot spectroscopy for wind and temperature measurements in the upper atmosphere, the derivation is generic and applicable to other spectroscopy problems with a Gaussian line shape.

Validation of the Chinese Version of the Quality of Nursing Work Life Scale

PubMed Central

Fu, Xia; Xu, Jiajia; Song, Li; Li, Hua; Wang, Jing; Wu, Xiaohua; Hu, Yani; Wei, Lijun; Gao, Lingling; Wang, Qiyi; Lin, Zhanyi; Huang, Huigen

2015-01-01

Quality of Nursing Work Life (QNWL) serves as a predictor of a nurse’s intent to leave and hospital nurse turnover. However, QNWL measurement tools that have been validated for use in China are lacking. The present study evaluated the construct validity of the QNWL scale in China. A cross-sectional study was conducted conveniently from June 2012 to January 2013 at five hospitals in Guangzhou, which employ 1938 nurses. The participants were asked to complete the QNWL scale and the World Health Organization Quality of Life abbreviated version (WHOQOL-BREF). A total of 1922 nurses provided the final data used for analyses. Sixty-five nurses from the first investigated division were re-measured two weeks later to assess the test-retest reliability of the scale. The internal consistency reliability of the QNWL scale was assessed using Cronbach’s α. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC). Criterion-relation validity was assessed using the correlation of the total scores of the QNWL and the WHOQOL-BREF. Construct validity was assessed with the following indices: χ2 statistics and degrees of freedom; relative mean square error of approximation (RMSEA); the Akaike information criterion (AIC); the consistent Akaike information criterion (CAIC); the goodness-of-fit index (GFI); the adjusted goodness of fit index; and the comparative fit index (CFI). The findings demonstrated high internal consistency (Cronbach’s α = 0.912) and test-retest reliability (interclass correlation coefficient = 0.74) for the QNWL scale. The chi-square test (χ2 = 13879.60, df [degree of freedom] = 813 P = 0.0001) was significant. The RMSEA value was 0.091, and AIC = 1806.00, CAIC = 7730.69, CFI = 0.93, and GFI = 0.74. The correlation coefficient between the QNWL total scores and the WHOQOL-BREF total scores was 0.605 (p<0.01). The QNWL scale was reliable and valid in Chinese-speaking nurses and could be used as a clinical and research instrument for measuring work-related factors among nurses in China. PMID:25950838

Compulsory military service as a measure of later physical and cognitive performance in male survivors of childhood cancer.

PubMed

Ahomäki, Ritva; Harila-Saari, Arja; Parkkola, Kai; Matomäki, Jaakko; Lähteenmäki, Päivi M

2017-12-01

Compromised physical fitness and cognitive difficulties have been reported as late effects of cancer treatment during childhood. To assess this issue, the military rankings of cancer survivors in medical checkups at call-up, and conscripts' physical and cognitive performance during the first weeks of compulsory military education were compared to those of matched population controls without a history of cancer. A total of 1680 male patients born between 1960 and 1992 with a malignancy diagnosed before the age of 16 who were alive at the call-up age (18 years) were identified using the Finnish Cancer Registry, and five age, sex and place of residence matched controls for each patient using the Population Register Centre. Data on military service were gathered from Finnish Defense Forces. A conditional logistic regression analysis, the GEE-method with the cumulative logit link function, the chi-square test, the chi-square test for trend and a one-way analysis of variance were used in different analyses. Cancer survivors were exempted from military service more often than the controls (p < .001). The fit-for-service frequency was highest for survivors of kidney tumors (68%) and lowest after irradiated brain tumors (19%). In service, the results of the 12-min running test were poorer than those of controls for leukemia/non-Hodgkin lymphoma (p = .03) and brain tumor (p = .01) survivors. Interestingly, the standing long-jump test was the only muscle test for which survivor groups performed worse than controls. Performance on cognitive tests only differed from controls in brain tumor survivors. Exemption from service is still common under the current guidelines, but fit-for-service survivors do well in military education. These results can be used for reassuring survivors that completion of military service is possible for those fulfilling the national general guidelines for military fitness.

Interstitial cystitis patients' use and rating of complementary and alternative medicine therapies.

PubMed

O'Hare, Peter Gregory; Hoffmann, Amy Rejba; Allen, Penny; Gordon, Barbara; Salin, Linda; Whitmore, Kristene

2013-06-01

The purpose of this study was to describe the use of complementary and alternative medicine (CAM) therapies among interstitial cystitis (IC) patients, patients' perception of CAM therapies' effectiveness, and the association of time since diagnosis with perceived effectiveness of these therapies. In April 2009, the Interstitial Cystitis Association (ICA) initiated an Internet-based survey on CAM. Respondents indicated whether they received an IC diagnosis and how long ago, whether they tried CAM, and who recommended it. On a 5-point scale, respondents rated 49 therapies. For respondents confirming a diagnosis, we used a chi-square goodness-of-fit test to assess which therapies were rated positively or negatively by a majority of patients who tried them. Using separate one-way analyses of variance, we assessed differences in mean perceived effectiveness among groups based on time since diagnosis and conducted post hoc tests, if necessary. Using chi-square tests, we explored the association of time since diagnosis with the use of CAM and the number of therapies tried. A total of 2,101 subjects responded to the survey; 1,982 confirmed an IC diagnosis. Most (84.2 %) had tried CAM, and 55 % said physicians had recommended CAM. Of those trying CAM, 82.8 % had tried diet or physical therapy and 69.2 % other therapies. Of the therapies, 22 were rated positively and 20 negatively; 7 were inconclusive. Therapies patients perceived to be helpful included dietary management and pain management adjuncts such as physical therapy, heat and cold, meditation and relaxation, acupuncture, stress reduction, exercise, and sleep hygiene. Many therapies worked better for those diagnosed recently than for those diagnosed long before. Randomized, placebo-controlled studies are needed to demonstrate which therapies may indeed control IC symptoms and help send research in new and productive directions.

Statistical Analysis And Treatment Of Accident Black Spots: A Case Study Of Nandyal Mandal

NASA Astrophysics Data System (ADS)

Sudharshan Reddy, B.; Vishnu Vardhan Reddy, L.; Sreenivasa Reddy, G., Dr

2017-08-01

Background: Increased, economic activity raised the consumption levels of the people across the country. This created scope for increase in travel and transportation. The increase in the vehicles since last 10 years has put lot of pressure on the existing roads and ultimately resulting in road accidents. Nandyal Mandal is located in the Kurnool district of Andhra Pradesh and well developed in both agricultural and industrial sectors after Kurnool. 567 accidents occurred in the last seven years at 143 locations shows the severity of the accidents in the Nandyal Mandal. There is a need to carry out some work in the Nandyal Mandal to improve the accidents black spots for reducing the accidents. Methods: Last seven years (2010-2016) of accident data collected from Police Stations. Weighted Severity Index (WSI), a scientific method is used for identifying the accident black spots. Statistical analysis has carried out for the collected data using Chi-Square Test to determine the independence of accidents with other attributes. Chi-Square Goodness of fit test conducted for test whether the accidents are occurring by chance or following any pattern. Results: WSI values are determined for the 143 locations. The Locations with high WSI are treated as accident black spots. Five black spots are taken for field study. After field observations and interaction with the public, some improvements are suggested for improving the accident black spots. There is no relationship between the severity of accidents and the other attributes like month, season, day, hours in day and the age group except type of vehicle. Road accidents are distributed throughout the Year, Month and Season. Road accidents are not distributed throughout the day.

F-Test Alternatives to Fisher's Exact Test and to the Chi-Square Test of Homogeneity in 2x2 Tables.

ERIC Educational Resources Information Center

Overall, John E.; Starbuck, Robert R.

1983-01-01

An alternative to Fisher's exact test and the chi-square test for homogeneity in two-by-two tables is developed. The method provides for Type I error rates which are closer to the stated alpha level than either of the alternatives. (JKS)

Estimation of Measurement Characteristics of Ultrasound Fetal Heart Rate Monitor

NASA Astrophysics Data System (ADS)

Noguchi, Yasuaki; Mamune, Hideyuki; Sugimoto, Suguru; Yoshida, Atsushi; Sasa, Hidenori; Kobayashi, Hisaaki; Kobayashi, Mitsunao

1995-05-01

Ultrasound fetal heart rate monitoring is very useful to determine the status of the fetus because it is noninvasive. In order to ensure the accuracy of the fetal heart rate (FHR) obtained from the ultrasound Doppler data, we measure the fetal electrocardiogram (ECG) directly and obtain the Doppler data simultaneously. The FHR differences of the Doppler data from the direct ECG data are concentrated at 0 bpm (beats per minute), and are practically symmetrical. The distribution is found to be very close to the Student's t distribution by the test of goodness of fit with the chi-square test. The spectral density of the FHR differences shows the white noise spectrum without any dominant peaks. Furthermore, the f-n (n>1) fluctuation is observed both with the ultrasound Doppler FHR and with the direct ECG FHR. Thus, it is confirmed that the FHR observation and observation of the f-n (n>1) fluctuation using the ultrasound Doppler FHR are as useful as the direct ECG.

Risk adjusted surgical audit in gynaecological oncology: P-POSSUM does not predict outcome.

PubMed

Das, N; Talaat, A S; Naik, R; Lopes, A D; Godfrey, K A; Hatem, M H; Edmondson, R J

2006-12-01

To assess the Physiological and Operative Severity Score for the enumeration of mortality and morbidity (POSSUM) and its validity for use in gynaecological oncology surgery. All patients undergoing gynaecological oncology surgery at the Northern Gynaecological Oncology Centre (NGOC) Gateshead, UK over a period of 12months (2002-2003) were assessed prospectively. Mortality and morbidity predictions using the Portsmouth modification of the POSSUM algorithm (P-POSSUM) were compared to the actual outcomes. Performance of the model was also evaluated using the Hosmer and Lemeshow Chi square statistic (testing the goodness of fit). During this period 468 patients were assessed. The P-POSSUM appeared to over predict mortality rates for our patients. It predicted a 7% mortality rate for our patients compared to an observed rate of 2% (35 predicted deaths in comparison to 10 observed deaths), a difference that was statistically significant (H&L chi(2)=542.9, d.f. 8, p<0.05). The P-POSSUM algorithm overestimates the risk of mortality for gynaecological oncology patients undergoing surgery. The P-POSSUM algorithm will require further adjustments prior to adoption for gynaecological cancer surgery as a risk adjusted surgical audit tool.

The Chi-Square Test: Often Used and More Often Misinterpreted

ERIC Educational Resources Information Center

Franke, Todd Michael; Ho, Timothy; Christie, Christina A.

2012-01-01

The examination of cross-classified category data is common in evaluation and research, with Karl Pearson's family of chi-square tests representing one of the most utilized statistical analyses for answering questions about the association or difference between categorical variables. Unfortunately, these tests are also among the more commonly…

Principles and Practice of Scaled Difference Chi-Square Testing

ERIC Educational Resources Information Center

Bryant, Fred B.; Satorra, Albert

2012-01-01

We highlight critical conceptual and statistical issues and how to resolve them in conducting Satorra-Bentler (SB) scaled difference chi-square tests. Concerning the original (Satorra & Bentler, 2001) and new (Satorra & Bentler, 2010) scaled difference tests, a fundamental difference exists in how to compute properly a model's scaling correction…

Health benefits of tai chi: What is the evidence?

PubMed

Huston, Patricia; McFarlane, Bruce

2016-11-01

To summarize the evidence on the health benefits of tai chi. A literature review was conducted on the benefits of tai chi for 25 specific conditions, as well as for general health and fitness, to update a 2014 review of systematic reviews. Systematic reviews and recent clinical trials were assessed and organized into 5 different groups: evidence of benefit as excellent, good, fair, or preliminary, or evidence of no direct benefit. During the past 45 years more than 500 trials and 120 systematic reviews have been published on the health benefits of tai chi. Systematic reviews of tai chi for specific conditions indicate excellent evidence of benefit for preventing falls, osteoarthritis, Parkinson disease, rehabilitation for chronic obstructive pulmonary disease, and improving cognitive capacity in older adults. There is good evidence of benefit for depression, cardiac and stroke rehabilitation, and dementia. There is fair evidence of benefit for improving quality of life for cancer patients, fibromyalgia, hypertension, and osteoporosis. Current evidence indicates no direct benefit for diabetes, rheumatoid arthritis, or chronic heart failure. Systematic reviews of general health and fitness benefits show excellent evidence of benefit for improving balance and aerobic capacity in those with poor fitness. There is good evidence for increased strength in the lower limbs. There is fair evidence for increased well-being and improved sleep. There were no studies that found tai chi worsened a condition. A recent systematic review on the safety of tai chi found adverse events were typically minor and primarily musculoskeletal; no intervention-related serious adverse events have been reported. There is abundant evidence on the health and fitness effects of tai chi. Based on this, physicians can now offer evidence-based recommendations to their patients, noting that tai chi is still an area of active research, and patients should continue to receive medical follow-up for any clinical conditions. Copyright© the College of Family Physicians of Canada.

Validation of the Pain Resilience Scale in Chinese-speaking patients with temporomandibular disorders pain.

PubMed

He, S L; Wang, J H; Ji, P

2018-03-01

To validate the Pain Resilience Scale (PRS) for use in Chinese patients with temporomandibular disorders (TMD) pain. According to international guidelines, the original PRS was first translated and cross-culturally adapted to formulate the Chinese version of PRS (PRS-C). A total of 152 patients with TMD pain were recruited to complete series of questionnaires. Reliability of the PRS-C was investigated using internal consistency and test-retest reliability. Validity of the PRS-C was calculated using cross-cultural validity and convergent validity. Cross-cultural validity was evaluated by examining the confirmatory factor analysis (CFA). And convergent validity was examined through correlating the PRS-C scores with scores of 2 commonly used pain-related measures (the Connor-Davidson Resilience Scale [CD-RISC] and the Tampa Scale for Kinesiophobia for Temporomandibular Disorders [TSK-TMD]). The PRS-C had a high internal consistency (Cronbach's alpha = 0.92) and good test-retest reliability (intra-class correlation coefficient [ICC] = 0.81). The CFA supported a 2-factor model for the PRS-C with acceptable fit to the data. The fit indices were chi-square/DF = 2.21, GFI = 0.91, TLI = 0.97, CFI = 0.98 and RMSEA = 0.08. As regards convergent validity, the PRS-C evidenced moderate-to-good relationships with the CD-RISC and the TSK-TMD. The PRS-C shows good psychometric properties and could be considered as a reliable and valid measure to evaluate pain-related resilience in patients with TMD pain. © 2017 John Wiley & Sons Ltd.

Psychometric properties of the medical outcomes study: social support survey among methadone maintenance patients in Ho Chi Minh City, Vietnam: a validation study.

PubMed

Khuong, Long Quynh; Vu, Tuong-Vi Thi; Huynh, Van-Anh Ngoc; Thai, Truc Thanh

2018-02-14

Social support plays a crucial role in the treatment and recovery process of patients engaging in methadone maintenance treatment (MMT). However, there is a paucity of research about social support among MMT patients, possibly due to a lack of appropriate measuring tools. This study aimed to evaluate the psychometric properties of the Vietnamese version of the Medical Outcomes Study: Social Support Survey (MOS-SSS) among MMT patients. A cross-sectional survey of 300 patients was conducted in a methadone clinic in Ho Chi Minh City, Vietnam. MMT patients who agreed to participate in the study completed a face-to-face interview in a private room. The MOS-SSS was translated into Vietnamese using standard forward-backward process. Internal consistency was measured by Cronbach's alpha. The intra-class correlation coefficient was used to determine the test-retest reliability of the MOS-SSS in 75 participants two weeks after the first survey. Concurrent validity of the MOS-SSS was evaluated by correlations with the Multidimensional Scale of Perceived Social Support (MSPSS) and the Perceived Stigma of Addiction Scale (PSAS). Construct validity was investigated by confirmatory factor analysis. The MOS-SSS had good internal consistency with Cronbach's alpha from 0.95 to 0.97 for the four subscales and 0.97 for the overall scale. The two-week test-retest reliability was at moderate level with intra-class correlation coefficients of 0.61-0.73 for the four subscales and 0.76 for the overall scale. Strong significant correlations between the MOS-SSS and the MSPSS (r = 0.77; p < 0.001) and the PSAS (r = - 0.76; p < 0.001) indicated good concurrent validity. Construct validity of the MOS-SSS was established since a final four-factor model fitted the data well with Comparative Fit Index (0.97), Tucker-Lewis Index (0.97), Standardized Root Mean Square Residual (0.03) and Root Mean Square Error of Approximation (0.068; 90% CI = 0.059-0.077). The MOS-SSS is a reliable and valid tool for measuring social support in Vietnamese MMT patients. Further studies among methadone patients at different stages of their treatment and among those from different areas of Vietnam are needed.

Adaptation to nursing home: The role of leisure activities in light of motivation and relatedness.

PubMed

Altintas, Emin; De Benedetto, Giorgio; Gallouj, Karim

Based on the motivational sequence described in Self-Determination Theory, this study explored the relationship between relatedness, motivation, adaptation and leisure in nursing homes. We formulated the hypothesis that the variables of the study would be found in an integrative mediational sequence: Participation in leisure activities→Relatedness→Self-determined motivation→Adaptation to nursing homes. Participants (N=112, mean age=84.17) were invited to complete questionnaires assessing these variables. Results of the path analysis found an unsatisfactory fit for this model but revealed another model (Model 2) with a good fit index: Relatedness→Participation in leisure activities→Self-determined motivation→Adaptation to nursing homes→Relatedness. Model 2 fitted better than model 1: the Chi-square values were not significant, Chi 2 (df=2)=5.1, p=0.078 and other indices were satisfactory (CFI=0.930, RMSEA=0.049 and NFI=0.918). These results suggest that feeling connected and secure in the relationships with others, and integrated as an individual to the group contribute to enhance leisure practice, self-determined motivation, and finally adaptation to life environment. Consequently, the relatedness promotes leisure activities practice which represents a central adaptive behavior in nursing homes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

On the appropriateness of applying chi-square distribution based confidence intervals to spectral estimates of helicopter flyover data

NASA Technical Reports Server (NTRS)

Rutledge, Charles K.

1988-01-01

The validity of applying chi-square based confidence intervals to far-field acoustic flyover spectral estimates was investigated. Simulated data, using a Kendall series and experimental acoustic data from the NASA/McDonnell Douglas 500E acoustics test, were analyzed. Statistical significance tests to determine the equality of distributions of the simulated and experimental data relative to theoretical chi-square distributions were performed. Bias and uncertainty errors associated with the spectral estimates were easily identified from the data sets. A model relating the uncertainty and bias errors to the estimates resulted, which aided in determining the appropriateness of the chi-square distribution based confidence intervals. Such confidence intervals were appropriate for nontonally associated frequencies of the experimental data but were inappropriate for tonally associated estimate distributions. The appropriateness at the tonally associated frequencies was indicated by the presence of bias error and noncomformity of the distributions to the theoretical chi-square distribution. A technique for determining appropriate confidence intervals at the tonally associated frequencies was suggested.

Tests of Independence in Contingency Tables with Small Samples: A Comparison of Statistical Power.

ERIC Educational Resources Information Center

Parshall, Cynthia G.; Kromrey, Jeffrey D.

1996-01-01

Power and Type I error rates were estimated for contingency tables with small sample sizes for the following four types of tests: (1) Pearson's chi-square; (2) chi-square with Yates's continuity correction; (3) the likelihood ratio test; and (4) Fisher's Exact Test. Various marginal distributions, sample sizes, and effect sizes were examined. (SLD)

Calibration of Self-Efficacy for Conducting a Chi-Squared Test of Independence

ERIC Educational Resources Information Center

Zimmerman, Whitney Alicia; Goins, Deborah D.

2015-01-01

Self-efficacy and knowledge, both concerning the chi-squared test of independence, were examined in education graduate students. Participants rated statements concerning self-efficacy and completed a related knowledge assessment. After completing a demographic survey, participants completed the self-efficacy and knowledge scales a second time.…

Normal versus Noncentral Chi-Square Asymptotics of Misspecified Models

ERIC Educational Resources Information Center

Chun, So Yeon; Shapiro, Alexander

2009-01-01

The noncentral chi-square approximation of the distribution of the likelihood ratio (LR) test statistic is a critical part of the methodology in structural equation modeling. Recently, it was argued by some authors that in certain situations normal distributions may give a better approximation of the distribution of the LR test statistic. The main…

Distributions of the Kullback-Leibler divergence with applications.

PubMed

Belov, Dmitry I; Armstrong, Ronald D

2011-05-01

The Kullback-Leibler divergence (KLD) is a widely used method for measuring the fit of two distributions. In general, the distribution of the KLD is unknown. Under reasonable assumptions, common in psychometrics, the distribution of the KLD is shown to be asymptotically distributed as a scaled (non-central) chi-square with one degree of freedom or a scaled (doubly non-central) F. Applications of the KLD for detecting heterogeneous response data are discussed with particular emphasis on test security. © The British Psychological Society.

Chi-square analysis of the reduction of ATP levels in L-02 hepatocytes by hexavalent chromium.

PubMed

Yuan, Yang; Peng, Li; Gong-Hua, Hu; Lu, Dai; Xia-Li, Zhong; Yu, Zhou; Cai-Gao, Zhong

2012-06-01

This study explored the reduction of adenosine triphosphate (ATP) levels in L-02 hepatocytes by hexavalent chromium (Cr(VI)) using chi-square analysis. Cells were treated with 2, 4, 8, 16, or 32 μM Cr(VI) for 12, 24, or 36 h. Methyl thiazolyl tetrazolium (MTT) experiments and measurements of intracellular ATP levels were performed by spectrophotometry or bioluminescence assays following Cr(VI) treatment. The chi-square test was used to determine the difference between cell survival rate and ATP levels. For the chi-square analysis, the results of the MTT or ATP experiments were transformed into a relative ratio with respect to the control (%). The relative ATP levels increased at 12 h, decreased at 24 h, and increased slightly again at 36 h following 4, 8, 16, 32 μM Cr(VI) treatment, corresponding to a "V-shaped" curve. Furthermore, the results of the chi-square analysis demonstrated a significant difference of the ATP level in the 32-μM Cr(VI) group (P < 0.05). The results suggest that the chi-square test can be applied to analyze the interference effects of Cr(VI) on ATP levels in L-02 hepatocytes. The decreased ATP levels at 24 h indicated disruption of mitochondrial energy metabolism and the slight increase of ATP levels at 36 h indicated partial recovery of mitochondrial function or activated glycolysis in L-02 hepatocytes.

False star detection and isolation during star tracking based on improved chi-square tests.

PubMed

Zhang, Hao; Niu, Yanxiong; Lu, Jiazhen; Yang, Yanqiang; Su, Guohua

2017-08-01

The star sensor is a precise attitude measurement device for a spacecraft. Star tracking is the main and key working mode for a star sensor. However, during star tracking, false stars become an inevitable interference for star sensor applications, which may result in declined measurement accuracy. A false star detection and isolation algorithm in star tracking based on improved chi-square tests is proposed in this paper. Two estimations are established based on a Kalman filter and a priori information, respectively. The false star detection is operated through adopting the global state chi-square test in a Kalman filter. The false star isolation is achieved using a local state chi-square test. Semi-physical experiments under different trajectories with various false stars are designed for verification. Experiment results show that various false stars can be detected and isolated from navigation stars during star tracking, and the attitude measurement accuracy is hardly influenced by false stars. The proposed algorithm is proved to have an excellent performance in terms of speed, stability, and robustness.

Using volcano plots and regularized-chi statistics in genetic association studies.

PubMed

Li, Wentian; Freudenberg, Jan; Suh, Young Ju; Yang, Yaning

2014-02-01

Labor intensive experiments are typically required to identify the causal disease variants from a list of disease associated variants in the genome. For designing such experiments, candidate variants are ranked by their strength of genetic association with the disease. However, the two commonly used measures of genetic association, the odds-ratio (OR) and p-value may rank variants in different order. To integrate these two measures into a single analysis, here we transfer the volcano plot methodology from gene expression analysis to genetic association studies. In its original setting, volcano plots are scatter plots of fold-change and t-test statistic (or -log of the p-value), with the latter being more sensitive to sample size. In genetic association studies, the OR and Pearson's chi-square statistic (or equivalently its square root, chi; or the standardized log(OR)) can be analogously used in a volcano plot, allowing for their visual inspection. Moreover, the geometric interpretation of these plots leads to an intuitive method for filtering results by a combination of both OR and chi-square statistic, which we term "regularized-chi". This method selects associated markers by a smooth curve in the volcano plot instead of the right-angled lines which corresponds to independent cutoffs for OR and chi-square statistic. The regularized-chi incorporates relatively more signals from variants with lower minor-allele-frequencies than chi-square test statistic. As rare variants tend to have stronger functional effects, regularized-chi is better suited to the task of prioritization of candidate genes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Power of tests for comparing trend curves with application to national immunization survey (NIS).

PubMed

Zhao, Zhen

2011-02-28

To develop statistical tests for comparing trend curves of study outcomes between two socio-demographic strata across consecutive time points, and compare statistical power of the proposed tests under different trend curves data, three statistical tests were proposed. For large sample size with independent normal assumption among strata and across consecutive time points, the Z and Chi-square test statistics were developed, which are functions of outcome estimates and the standard errors at each of the study time points for the two strata. For small sample size with independent normal assumption, the F-test statistic was generated, which is a function of sample size of the two strata and estimated parameters across study period. If two trend curves are approximately parallel, the power of Z-test is consistently higher than that of both Chi-square and F-test. If two trend curves cross at low interaction, the power of Z-test is higher than or equal to the power of both Chi-square and F-test; however, at high interaction, the powers of Chi-square and F-test are higher than that of Z-test. The measurement of interaction of two trend curves was defined. These tests were applied to the comparison of trend curves of vaccination coverage estimates of standard vaccine series with National Immunization Survey (NIS) 2000-2007 data. Copyright © 2011 John Wiley & Sons, Ltd.

Perception of competence in middle school physical education: instrument development and validation.

PubMed

Scrabis-Fletcher, Kristin; Silverman, Stephen

2010-03-01

Perception of Competence (POC) has been studied extensively in physical activity (PA) research with similar instruments adapted for physical education (PE) research. Such instruments do not account for the unique PE learning environment. Therefore, an instrument was developed and the scores validated to measure POC in middle school PE. A multiphase design was used consisting of an intensive theoretical review, elicitation study, prepilot study, pilot study, content validation study, and final validation study (N=1281). Data analysis included a multistep iterative process to identify the best model fit. A three-factor model for POC was tested and resulted in root mean square error of approximation = .09, root mean square residual = .07, goodness offit index = .90, and adjusted goodness offit index = .86 values in the acceptable range (Hu & Bentler, 1999). A two-factor model was also tested and resulted in a good fit (two-factor fit indexes values = .05, .03, .98, .97, respectively). The results of this study suggest that an instrument using a three- or two-factor model provides reliable and valid scores ofPOC measurement in middle school PE.

Study about the effects of different fitness sports on cognitive function and emotion of the aged.

PubMed

Zhang, Xinan; Ni, Xiaomei; Chen, Peijie

2014-12-01

The aim of the study was to explore the effects of different fitness sports on cognitive function and emotion of the aged people. A total of 150 subjects aged between 60 and 70 were recruited from Shenyang Aged University and elderly activity center. All subjects reported no fitness before this study. The aged subjects were divided into five groups, included swimming group (A group), running group (B group), square dancing group (C group), Tai Chi group (D group) and control group (E group) with 30 people in each group. Subjects in each group received exercise intervention continued for 18 months. At baseline, 6, 12 and 18 months after intervention, the P300 test, SECF, HAMD and HAMA scale evaluations were performed. Compared to E group, the P2, N2 and P3 latency and response time in the D group after intervention for 6 months, and in the A-C groups after intervention for 12 months were significantly prolonged. The anxiety symptom and depression levels in the A-D groups after intervention for 12 months were significantly decreased when compared to E group (P < 0. 01), where significantly improved compared with the E group (P < 0. 01). The effect of exercise intervention for Tai Chi group was the most significant. Different fitness sports have marked beneficial effect on cognitive function and emotion of the aged people, especially the Tai Chi exercise.

Earth Observing System Covariance Realism

NASA Technical Reports Server (NTRS)

Zaidi, Waqar H.; Hejduk, Matthew D.

2016-01-01

The purpose of covariance realism is to properly size a primary object's covariance in order to add validity to the calculation of the probability of collision. The covariance realism technique in this paper consists of three parts: collection/calculation of definitive state estimates through orbit determination, calculation of covariance realism test statistics at each covariance propagation point, and proper assessment of those test statistics. An empirical cumulative distribution function (ECDF) Goodness-of-Fit (GOF) method is employed to determine if a covariance is properly sized by comparing the empirical distribution of Mahalanobis distance calculations to the hypothesized parent 3-DoF chi-squared distribution. To realistically size a covariance for collision probability calculations, this study uses a state noise compensation algorithm that adds process noise to the definitive epoch covariance to account for uncertainty in the force model. Process noise is added until the GOF tests pass a group significance level threshold. The results of this study indicate that when outliers attributed to persistently high or extreme levels of solar activity are removed, the aforementioned covariance realism compensation method produces a tuned covariance with up to 80 to 90% of the covariance propagation timespan passing (against a 60% minimum passing threshold) the GOF tests-a quite satisfactory and useful result.

Agreement among readers on what is relevant in self-help psychology books.

PubMed

Forest, James J; Del Ben, Kevin; Toews, Stuart B

2003-12-01

It was hypothesized that text marking in self-help psychology books would indicate that readers agree on which pages and lines contain relevant information. Previously owned copies of two self-help book titles (n=48, n=38), all with marked text, were collected from second-hand book stores and scored for line and page marking. Chi-squares for goodness-of-fit yielded significant differences between observed and chance agreement in marking behavior. Intraclass and KR-20 correlations were significantly different from zero, suggesting that readers agreed on what information was relevant and irrelevant. Actual users of self-help books may have similar standards because of cultural values, social group relations, or common problem experiences.

Colour Preference to Emotions in Relation to the Anxiety Level among School Children in Puducherry – A Cross-Sectional Study

PubMed Central

Prathima, Gajula Shivashankarappa; Sajeev, Renganathan; Kayalvizhi, Gurusamy; Ramesh, Venkatesan; Ezhumalai, Govindasamy

2016-01-01

Introduction Dental setting plays an important role in child’s behavior and cooperation to the planned dental treatment. Adding attractive colours to the dental environment and by incorporating colourful equipments can make the child feel good and be at ease. This study tries to convey the relationship between colours and dental anxiety among children. Aim To evaluate the colour preference to emotions in relation to children’s age, gender and anxiety level. Materials and Methods A total of 382 children aged 6-12 years were randomly selected from schools in and around Puducherry. Modified dental anxiety scale was recorded by a calibrated examiner. Each question was scored from one (not anxious) to five (extremely anxious); such that the total score ranges from 5 to 25, wherein a score of 15 or more was considered to be anxious. Based on this, children were divided into anxious and non-anxious groups. All the children were provided with eight different coloured crayon pencils and were asked to shade two cartoon emoticons indicating happiness and sadness with their preferred colour. Values were tabulated and statistically analyzed to evaluate the association between the variables using Z test, Chi-square, Chi-square goodness of fit and odds ratio. (p≤0.05 was considered statistically significant). Results Among 382 children, 77% (294) were graded as anxious and 23% (88) as non- anxious. For positive emotion (happiness), 31.2% (119) children preferred blue followed by pink 29.3% (112). For negative emotion (sadness), 52.1% (199) of children preferred black and 46.9% (179) preferred red. Association between colour and emotion was highly significant (p= 0.005). Conclusion From the colours preferred by the children in our study, it can be concluded that colours like blue and pink in the dental set-up could enhance a positive attitude while black and red could develop a negative outlook in their mind. PMID:27630948

Colour Preference to Emotions in Relation to the Anxiety Level among School Children in Puducherry - A Cross-Sectional Study.

PubMed

Annamary, Kattakayam; Prathima, Gajula Shivashankarappa; Sajeev, Renganathan; Kayalvizhi, Gurusamy; Ramesh, Venkatesan; Ezhumalai, Govindasamy

2016-07-01

Dental setting plays an important role in child's behavior and cooperation to the planned dental treatment. Adding attractive colours to the dental environment and by incorporating colourful equipments can make the child feel good and be at ease. This study tries to convey the relationship between colours and dental anxiety among children. To evaluate the colour preference to emotions in relation to children's age, gender and anxiety level. A total of 382 children aged 6-12 years were randomly selected from schools in and around Puducherry. Modified dental anxiety scale was recorded by a calibrated examiner. Each question was scored from one (not anxious) to five (extremely anxious); such that the total score ranges from 5 to 25, wherein a score of 15 or more was considered to be anxious. Based on this, children were divided into anxious and non-anxious groups. All the children were provided with eight different coloured crayon pencils and were asked to shade two cartoon emoticons indicating happiness and sadness with their preferred colour. Values were tabulated and statistically analyzed to evaluate the association between the variables using Z test, Chi-square, Chi-square goodness of fit and odds ratio. (p≤0.05 was considered statistically significant). Among 382 children, 77% (294) were graded as anxious and 23% (88) as non- anxious. For positive emotion (happiness), 31.2% (119) children preferred blue followed by pink 29.3% (112). For negative emotion (sadness), 52.1% (199) of children preferred black and 46.9% (179) preferred red. Association between colour and emotion was highly significant (p= 0.005). From the colours preferred by the children in our study, it can be concluded that colours like blue and pink in the dental set-up could enhance a positive attitude while black and red could develop a negative outlook in their mind.

[Development of a Questionnaire Measuring Sexual Mental Health of Tibetan University Students].

PubMed

Chen, Jun-cheng; Yan, Yu-ruo; Ai, Li; Guo, Xue-hua; He, Jian-xiu; Yuan, Ping

2016-05-01

To develop a questionnaire measuring sexual mental health of Tibetan university students. A draft questionnaire was developed with reference to the Sexual Civilization Survey for University Students of New Century and other published literature, and in consultation with experts. The questionnaire was tested in 230 students. Exploratory factor analyses with principal component and varimax orthogonal rotation were performed. Common factors with a > 1 eigenvalues and ≥ 3 loaded items (factor loading ≥ 0.4) were retained. Items with a < 0.4 factor loading, < 0.2 commonality, or falling into a common factor with < 3 items were excluded. The revised questionnaire was administered in another sample of 481 university students. Cronbach's α and split-half reliabilities were estimated. Confirmatory factor analyses were performed to test the construct validity of the questionnaire. Four rounds of exploratory factor analyses reduced the draft questionnaire items from 39 to 34 with a 7-factor structure. The questionnaire had a Cronbach's α of 0.920, 0.898, 0.812, 0.844, 0.787, 0.684, 0.703, and 0.608, and a Spearman-Brown coefficient of 0.763, 0.867, 0.742, 0838, 0.746, 0.822, 0.677, and 0.564 for the overall questionnaire and its 7 domains, respectively, suggesting good internal reliability. The structural equation of confirmatory factor analysis fitted well with the raw data: fit index χ²/df 3.736; root mean square residual (RMR) 0.081; root mean square error of approximation (RMSEA = 0.076; goodness of fit index (GFI) 0.805; adjusted goodness of fit index (AGFI) 0.770; normed fit index (NFI) = 0.774; relative fit index (RFI) 0.749; incremental fit index (IFI) 0.824; non-normed fit index (NNFI) = 0.803; comparative fit index (CFI) = 0.823; parsimony goodness of fit index (PGFI) = 0.684; parsimony normed fit index (PNFI) = 0.698; parsimony comparative fit index (PCFI) = 0.742, suggesting good construct validity of the questionnaire. The Sexual Mental Health Questionnaire for Tibetan University Student has demonstrated good reliability and validity.

Cross-cultural adaptation and validation of the osteoporosis assessment questionnaire short version (OPAQ-SV) for Chinese osteoporotic fracture females.

PubMed

Zhang, Yin-Ping; Wei, Huan-Huan; Wang, Wen; Xia, Ru-Yi; Zhou, Xiao-Ling; Porr, Caroline; Lammi, Mikko

2016-04-01

The Osteoporosis Assessment Questionnaire Short Version (OPAQ-SV) was cross-culturally adapted to measure health-related quality of life in Chinese osteoporotic fracture females and then validated in China for its psychometric properties. Cross-cultural adaptation, including translation of the original OPAQ-SV into Mandarin Chinese language, was performed according to published guidelines. Validation of the newly cross-culturally adapted OPAQ-SV was conducted by sampling 234 Chinese osteoporotic fracture females and also a control group of 235 Chinese osteoporotic females without fractures, producing robust content, construct, and discriminant validation results. Major categories of reliability were also met: the Cronbach alpha coefficient was 0.975, indicating good internal consistency; the test-retest reliability was 0.80; and principal component analysis resulted in a 6-factor structure explaining 75.847 % of the total variance. Further, the Comparative Fit Index result was 0.922 following the modified model confirmatory factor analysis, and the chi-squared test was 1.98. The root mean squared error of approximation was 0.078. Moreover, significant differences were revealed between females with fractures and those without fractures across all domains (p < 0.001). Overall, the newly cross-culturally adapted OPAQ-SV appears to possess adequate validity and reliability and may be utilized in clinical trials to assess the health-related quality of life in Chinese osteoporotic fracture females.

[Association between health anthropometric indexes with physical fitness in physically active elderly women].

PubMed

Valdés-Badilla, Pablo; Godoy-Cumillaf, Andrés; Ortega-Spuler, Jenny; Herrera-Valenzuela, Tomás; Durán-Agüero, Samuel; Zapata-Bastias, José; Vargas-Vitoria, Rodrigo; Guzmán-Muñoz, Eduardo; López-Fuenzalida, Antonio

2017-01-01

To associate health anthropometric indexes with physical fitness of elderly women (EW) who participate in physical exercise workshops. 272 Chilean women over 60 years took part in the study. The variables studied were BMI, waist circumference (WC), waist-height index (WHI) and physical fitness (PF). Correlations were made through the Pearson or Spearman coefficient, and bivariate associations using Pearson's Chi-square and the Fisher's exact test, considering p<0.05. 70.8% of the EW were overweight or obese; 68.8% and 96% were at cardiometabolic risk due to their WC and WHI, respectively. Their PF showed equal performance (53.5%) or higher (33.8%) according to their age and gender. Inverse correlations were found between nutritional status and cardiometabolic risk with PF tests (except for agility and dynamic balance [direct]), and direct association with back scratch test. Excess weight in physically active EW would not affect their physical-functional performance; however, cardiometabolic risk would be inversely associated with motor function.

Muscular and Cardiorespiratory Fitness in Homeschool versus Public School Children.

PubMed

Kabiri, Laura S; Mitchell, Katy; Brewer, Wayne; Ortiz, Alexis

2017-08-01

The growth and unregulated structure of homeschooling creates an unknown population in regard to muscular and cardiorespiratory fitness. The purpose of this research was to compare muscular and cardiorespiratory fitness between elementary school aged homeschool and public school children. Homeschool children ages 8-11 years old (n = 75) completed the curl-up, 90° push-up, and Progressive Aerobic Capacity Endurance Run (PACER) portions of the FitnessGram to assess abdominal and upper body strength and endurance as well as cardiorespiratory fitness. Comparisons to public school children (n = 75) were made using t tests and chi-square tests. Homeschool children showed significantly lower abdominal (t(148) = -11.441, p < .001; χ 2 (1) = 35.503, p < .001) and upper body (t(148) = -3.610, p < .001; χ 2 (1) = 4.881, p = .027) strength and endurance. There were no significant differences in cardiorespiratory fitness by total PACER laps (t(108) = 0.879, p = .381) or estimated VO 2max (t(70) = 1.187, p = .239; χ 2 (1) = 1.444, p = .486). Homeschool children showed significantly lower levels of both abdominal and upper body muscular fitness compared with their age and gender matched public school peers but no difference in cardiorespiratory fitness.

Modelling road accident blackspots data with the discrete generalized Pareto distribution.

PubMed

Prieto, Faustino; Gómez-Déniz, Emilio; Sarabia, José María

2014-10-01

This study shows how road traffic networks events, in particular road accidents on blackspots, can be modelled with simple probabilistic distributions. We considered the number of crashes and the number of fatalities on Spanish blackspots in the period 2003-2007, from Spanish General Directorate of Traffic (DGT). We modelled those datasets, respectively, with the discrete generalized Pareto distribution (a discrete parametric model with three parameters) and with the discrete Lomax distribution (a discrete parametric model with two parameters, and particular case of the previous model). For that, we analyzed the basic properties of both parametric models: cumulative distribution, survival, probability mass, quantile and hazard functions, genesis and rth-order moments; applied two estimation methods of their parameters: the μ and (μ+1) frequency method and the maximum likelihood method; used two goodness-of-fit tests: Chi-square test and discrete Kolmogorov-Smirnov test based on bootstrap resampling; and compared them with the classical negative binomial distribution in terms of absolute probabilities and in models including covariates. We found that those probabilistic models can be useful to describe the road accident blackspots datasets analyzed. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Third Moment Adjusted Test Statistic for Small Sample Factor Analysis.

PubMed

Lin, Johnny; Bentler, Peter M

2012-01-01

Goodness of fit testing in factor analysis is based on the assumption that the test statistic is asymptotically chi-square; but this property may not hold in small samples even when the factors and errors are normally distributed in the population. Robust methods such as Browne's asymptotically distribution-free method and Satorra Bentler's mean scaling statistic were developed under the presumption of non-normality in the factors and errors. This paper finds new application to the case where factors and errors are normally distributed in the population but the skewness of the obtained test statistic is still high due to sampling error in the observed indicators. An extension of Satorra Bentler's statistic is proposed that not only scales the mean but also adjusts the degrees of freedom based on the skewness of the obtained test statistic in order to improve its robustness under small samples. A simple simulation study shows that this third moment adjusted statistic asymptotically performs on par with previously proposed methods, and at a very small sample size offers superior Type I error rates under a properly specified model. Data from Mardia, Kent and Bibby's study of students tested for their ability in five content areas that were either open or closed book were used to illustrate the real-world performance of this statistic.

An Item Fit Statistic Based on Pseudocounts from the Generalized Graded Unfolding Model: A Preliminary Report.

ERIC Educational Resources Information Center

Roberts, James S.

Stone and colleagues (C. Stone, R. Ankenman, S. Lane, and M. Liu, 1993; C. Stone, R. Mislevy and J. Mazzeo, 1994; C. Stone, 2000) have proposed a fit index that explicitly accounts for the measurement error inherent in an estimated theta value, here called chi squared superscript 2, subscript i*. The elements of this statistic are natural…

Data Reduction Pipeline for the CHARIS Integral-Field Spectrograph I: Detector Readout Calibration and Data Cube Extraction

NASA Technical Reports Server (NTRS)

Groff, Tyler; Rizzo, Maxime; Greco, Johnny P.; Loomis, Craig; Mede, Kyle; Kasdin, N. Jeremy; Knapp, Gillian; Tamura, Motohide; Hayashi, Masahiko; Galvin, Michael;

A measurement model of multiple intelligence profiles of management graduates

NASA Astrophysics Data System (ADS)

Krishnan, Heamalatha; Awang, Siti Rahmah

2017-05-01

In this study, developing a fit measurement model and identifying the best fitting items to represent Howard Gardner's nine intelligences namely, musical intelligence, bodily-kinaesthetic intelligence, mathematical/logical intelligence, visual/spatial intelligence, verbal/linguistic intelligence, interpersonal intelligence, intrapersonal intelligence, naturalist intelligence and spiritual intelligence are the main interest in order to enhance the opportunities of the management graduates for employability. In order to develop a fit measurement model, Structural Equation Modeling (SEM) was applied. A psychometric test which is the Ability Test in Employment (ATIEm) was used as the instrument to measure the existence of nine types of intelligence of 137 University Teknikal Malaysia Melaka (UTeM) management graduates for job placement purposes. The initial measurement model contains nine unobserved variables and each unobserved variable is measured by ten observed variables. Finally, the modified measurement model deemed to improve the Normed chi-square (NC) = 1.331; Incremental Fit Index (IFI) = 0.940 and Root Mean Square of Approximation (RMSEA) = 0.049 was developed. The findings showed that the UTeM management graduates possessed all nine intelligences either high or low. Musical intelligence, mathematical/logical intelligence, naturalist intelligence and spiritual intelligence contributed highest loadings on certain items. However, most of the intelligences such as bodily kinaesthetic intelligence, visual/spatial intelligence, verbal/linguistic intelligence interpersonal intelligence and intrapersonal intelligence possessed by UTeM management graduates are just at the borderline.

Normal tissue complication probability model parameter estimation for xerostomia in head and neck cancer patients based on scintigraphy and quality of life assessments

PubMed Central

2012-01-01

Background With advances in modern radiotherapy (RT), many patients with head and neck (HN) cancer can be effectively cured. However, xerostomia is a common complication in patients after RT for HN cancer. The purpose of this study was to use the Lyman–Kutcher–Burman (LKB) model to derive parameters for the normal tissue complication probability (NTCP) for xerostomia based on scintigraphy assessments and quality of life (QoL) questionnaires. We performed validation tests of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) guidelines against prospectively collected QoL and salivary scintigraphic data. Methods Thirty-one patients with HN cancer were enrolled. Salivary excretion factors (SEFs) measured by scintigraphy and QoL data from self-reported questionnaires were used for NTCP modeling to describe the incidence of grade 3+ xerostomia. The NTCP parameters estimated from the QoL and SEF datasets were compared. Model performance was assessed using Pearson’s chi-squared test, Nagelkerke’s R2, the area under the receiver operating characteristic curve, and the Hosmer–Lemeshow test. The negative predictive value (NPV) was checked for the rate of correctly predicting the lack of incidence. Pearson’s chi-squared test was used to test the goodness of fit and association. Results Using the LKB NTCP model and assuming n=1, the dose for uniform irradiation of the whole or partial volume of the parotid gland that results in 50% probability of a complication (TD50) and the slope of the dose–response curve (m) were determined from the QoL and SEF datasets, respectively. The NTCP-fitted parameters for local disease were TD50=43.6 Gy and m=0.18 with the SEF data, and TD50=44.1 Gy and m=0.11 with the QoL data. The rate of grade 3+ xerostomia for treatment plans meeting the QUANTEC guidelines was specifically predicted, with a NPV of 100%, using either the QoL or SEF dataset. Conclusions Our study shows the agreement between the NTCP parameter modeling based on SEF and QoL data, which gave a NPV of 100% with each dataset, and the QUANTEC guidelines, thus validating the cut-off values of 20 and 25 Gy. Based on these results, we believe that the QUANTEC 25/20-Gy spared-gland mean-dose guidelines are clinically useful for avoiding xerostomia in the HN cohort. PMID:23206972

Normal tissue complication probability model parameter estimation for xerostomia in head and neck cancer patients based on scintigraphy and quality of life assessments.

PubMed

Lee, Tsair-Fwu; Chao, Pei-Ju; Wang, Hung-Yu; Hsu, Hsuan-Chih; Chang, PaoShu; Chen, Wen-Cheng

2012-12-04

With advances in modern radiotherapy (RT), many patients with head and neck (HN) cancer can be effectively cured. However, xerostomia is a common complication in patients after RT for HN cancer. The purpose of this study was to use the Lyman-Kutcher-Burman (LKB) model to derive parameters for the normal tissue complication probability (NTCP) for xerostomia based on scintigraphy assessments and quality of life (QoL) questionnaires. We performed validation tests of the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) guidelines against prospectively collected QoL and salivary scintigraphic data. Thirty-one patients with HN cancer were enrolled. Salivary excretion factors (SEFs) measured by scintigraphy and QoL data from self-reported questionnaires were used for NTCP modeling to describe the incidence of grade 3+ xerostomia. The NTCP parameters estimated from the QoL and SEF datasets were compared. Model performance was assessed using Pearson's chi-squared test, Nagelkerke's R2, the area under the receiver operating characteristic curve, and the Hosmer-Lemeshow test. The negative predictive value (NPV) was checked for the rate of correctly predicting the lack of incidence. Pearson's chi-squared test was used to test the goodness of fit and association. Using the LKB NTCP model and assuming n=1, the dose for uniform irradiation of the whole or partial volume of the parotid gland that results in 50% probability of a complication (TD50) and the slope of the dose-response curve (m) were determined from the QoL and SEF datasets, respectively. The NTCP-fitted parameters for local disease were TD50=43.6 Gy and m=0.18 with the SEF data, and TD50=44.1 Gy and m=0.11 with the QoL data. The rate of grade 3+ xerostomia for treatment plans meeting the QUANTEC guidelines was specifically predicted, with a NPV of 100%, using either the QoL or SEF dataset. Our study shows the agreement between the NTCP parameter modeling based on SEF and QoL data, which gave a NPV of 100% with each dataset, and the QUANTEC guidelines, thus validating the cut-off values of 20 and 25 Gy. Based on these results, we believe that the QUANTEC 25/20-Gy spared-gland mean-dose guidelines are clinically useful for avoiding xerostomia in the HN cohort.

Performance of the S - [chi][squared] Statistic for Full-Information Bifactor Models

ERIC Educational Resources Information Center

Li, Ying; Rupp, Andre A.

2011-01-01

This study investigated the Type I error rate and power of the multivariate extension of the S - [chi][squared] statistic using unidimensional and multidimensional item response theory (UIRT and MIRT, respectively) models as well as full-information bifactor (FI-bifactor) models through simulation. Manipulated factors included test length, sample…

GOSSIP: SED fitting code

NASA Astrophysics Data System (ADS)

Franzetti, Paolo; Scodeggio, Marco

2012-10-01

GOSSIP fits the electro-magnetic emission of an object (the SED, Spectral Energy Distribution) against synthetic models to find the simulated one that best reproduces the observed data. It builds-up the observed SED of an object (or a large sample of objects) combining magnitudes in different bands and eventually a spectrum; then it performs a chi-square minimization fitting procedure versus a set of synthetic models. The fitting results are used to estimate a number of physical parameters like the Star Formation History, absolute magnitudes, stellar mass and their Probability Distribution Functions.

Measuring the Nursing Work Environment in Mainland China: Further Development of the Chinese Nursing Work Environment Scale.

PubMed

Shao, Jing; Tang, Leiwen; Ye, Zhihong

For the stabilization of the nursing profession in mainland China, a valid and reliable nursing work environment instrument, grounded in China's context, should be developed to better provide rigorous evidence for policy makers. The purpose of the current research was to further develop a scale that could capture the characteristics of the nursing work environment in mainland China. A convenience sample of 542 nurses employed in a tertiary hospital of mainland China completed the 108-item Chinese Nursing Work Environment (C-NWE) Scale (1st ed.). Items that did not differentiate between respondents with the highest and lowest 27% of total scores and those that did not meet criteria for factor loadings were set aside. Exploratory factor analysis based on the maximum likelihood method was used to identify the structure of the scale. The chi-square test was used to evaluate model fit, and expert review was conducted to test content validity. Reliability was estimated using Cronbach's alpha coefficient. The revised C-NWE Scale, which consists of nine subscales and 47 items, is a simplified version of the C-NWE (1st ed.). Using exploratory maximum likelihood factor analysis, the normed chi-square fit index for a nine-factor solution was 1.97. The content validity index for the total scale was 0.93; Cronbach's alpha was .94. Initial evidence of the psychometric properties of C-NWE scores was presented. Further studies could be conducted in various settings to identify the C-NWE Scale's validity and reliability.

Effects of Sun-style Tai Chi exercise on physical fitness and fall prevention in fall-prone older adults.

PubMed

Choi, Jung Hyun; Moon, Jung-Soon; Song, Rhayun

2005-07-01

This paper reports a study to determine changes in the physical fitness (knee and ankle muscle strength, balance, flexibility, and mobility), fall avoidance efficacy, and fall episodes of institutionalized older adults after participating in a 12-week Sun-style Tai Chi exercise programme. Fall prevention has a high priority in health promotion for older people because a fall is associated with serious morbidity in this population. Regular exercise is effective in fall prevention for older adults because of improvements in strength and balance. Tai Chi exercise is considered to offer great potential for health promotion and rehabilitation, particularly in the maintenance of good mental and physical condition in older people. A quasi-experimental design with a non-equivalent control group was used. Data were collected from September 2001 to January 2002. A total of 68 fall-prone older adults with a mean age of 77.8 years participated in the study, and 29 people in the Tai Chi group and 30 controls completed the post-test measures. The Tai Chi exercise programme was provided three times a week for 12 weeks in the experimental group. Data were analysed for group differences using t-tests. At post-test, the experimental group showed significantly improved muscle strength in knee and ankle flexors (P < 0.001) and extensors (P < 0.01), and improved flexibility (P < 0.01) and mobility (P < 0.001) compared with the control group. There was no significant group difference in fall episodes, but the relative risk ratio for the Tai Chi exercise group compared with the control group was 0.62. The experimental group reported significantly more confidence in fall avoidance than did the control group. The findings reveal that Tai Chi exercise programmes can safely improve physical strength and reduce fall risk for fall-prone older adults in residential care facilities.

Product Quality Research Institute evaluation of cascade impactor profiles of pharmaceutical aerosols: part 2--evaluation of a method for determining equivalence.

PubMed

Christopher, David; Adams, Wallace P; Lee, Douglas S; Morgan, Beth; Pan, Ziqing; Singh, Gur Jai Pal; Tsong, Yi; Lyapustina, Svetlana

2007-01-19

The purpose of this article is to present the thought process, methods, and interim results of a PQRI Working Group, which was charged with evaluating the chi-square ratio test as a potential method for determining in vitro equivalence of aerodynamic particle size distribution (APSD) profiles obtained from cascade impactor measurements. Because this test was designed with the intention of being used as a tool in regulatory review of drug applications, the capability of the test to detect differences in APSD profiles correctly and consistently was evaluated in a systematic way across a designed space of possible profiles. To establish a "base line," properties of the test in the simplest case of pairs of identical profiles were studied. Next, the test's performance was studied with pairs of profiles, where some difference was simulated in a systematic way on a single deposition site using realistic product profiles. The results obtained in these studies, which are presented in detail here, suggest that the chi-square ratio test in itself is not sufficient to determine equivalence of particle size distributions. This article, therefore, introduces the proposal to combine the chi-square ratio test with a test for impactor-sized mass based on Population Bioequivalence and describes methods for evaluating discrimination capabilities of the combined test. The approaches and results described in this article elucidate some of the capabilities and limitations of the original chi-square ratio test and provide rationale for development of additional tests capable of comparing APSD profiles of pharmaceutical aerosols.

Psychometric Properties and Correlates of the Beck Hopelessness Scale in Family Caregivers of Nigerian Patients with Psychiatric Disorders in Southwestern Nigeria

PubMed Central

Aloba, Olutayo; Ajao, Olayinka; Alimi, Taiwo; Esan, Olufemi

2016-01-01

Objectives: To examine the construct and correlates of hopelessness among family caregivers of Nigerian psychiatric patients. Materials and Methods: This is a cross-sectional, descriptive study involving 264 family caregiver-patients’ dyads recruited from two university teaching hospitals psychiatric clinics in Southwestern Nigeria. Results: Exploratory factor analysis revealed a two-factor 9-item model of the Beck Hopelessness Scale (BHS) among the family caregivers. Confirmatory factor analysis of the model revealed satisfactory indices of fitness (goodness of fit index = 0.97, comparative fit index = 0.96, Chi-square/degree of freedom (CMIN/DF) = 1.60, root mean square error of approximation = 0.048, expected cross-validation index = 0.307, and standardized root mean residual = 0.005). Reliability of the scale was modestly satisfactory (Cronbach's alpha 0.72). Construct validity of scale was supported by significant correlations with the family caregivers’ scores on the Zarit Burden Interview, mini international neuropsychiatric interview suicidality module, General Health Questionnaire-12 (GHQ-12), and Patient Health Questionnaire-9. The greatest variance in the family caregivers’ scores on the BHS was contributed by their scores on the psychological distress scale (GHQ-12). Conclusions: The BHS has adequate psychometric properties among Nigerian psychiatric patients’ family caregivers. There is the need to pay attention to the psychological well-being of the family caregivers of Nigerian psychiatric patients. PMID:28163498

Students' motivational processes and their relationship to teacher ratings in school physical education: a self-determination theory approach.

PubMed

Standage, Martyn; Duda, Joan L; Ntoumanis, Nikos

2006-03-01

In the present study, we used a model of motivation grounded in self-determination theory (Deci & Ryan, 1985, 1991; Ryan & Deci, 2000a, 2000b, 2002) to examine the relationship between physical education (PE) students' motivational processes and ratings of their effort and persistence as provided by their PE teacher. Data were obtained from 394 British secondary school students (204 boys, 189 girls, 1 gender not specified; M age = 11.97 years; SD = .89; range = 11-14 years) who responded to a multisection inventory (tapping autonomy-support, autonomy, competence, relatedness, and self-determined motivation). The students' respective PE teachers subsequently provided ratings reflecting the effort and persistence each student exhibited in their PE classes. The hypothesized relationships among the study variables were examined via structural equation modeling analysis using latent factors. Results of maximum likelihood analysis using the bootstrapping method revealed the proposed model demonstrated a good fit to the data, chi-squared (292) = 632.68, p < .001; comparative fit index = .95; incremental fit index = .95, standardized root mean square residual = .077; root mean square error of approximation (RMSEA) = .054 (90% confidence interval of RMSEA = .049 -.060). Specifically, the model showed that students who perceived an autonomy supportive environment experienced greater levels of autonomy, competence, and relatedness and had higher scores on an index of self-determination. Student-reported levels of self-determined motivation positively predicted teacher ratings of effort and persistence in PE. The findings are discussed with regard to enhancing student motivation in PE settings.

Model Fit and Item Factor Analysis: Overfactoring, Underfactoring, and a Program to Guide Interpretation.

PubMed

Clark, D Angus; Bowles, Ryan P

2018-04-23

In exploratory item factor analysis (IFA), researchers may use model fit statistics and commonly invoked fit thresholds to help determine the dimensionality of an assessment. However, these indices and thresholds may mislead as they were developed in a confirmatory framework for models with continuous, not categorical, indicators. The present study used Monte Carlo simulation methods to investigate the ability of popular model fit statistics (chi-square, root mean square error of approximation, the comparative fit index, and the Tucker-Lewis index) and their standard cutoff values to detect the optimal number of latent dimensions underlying sets of dichotomous items. Models were fit to data generated from three-factor population structures that varied in factor loading magnitude, factor intercorrelation magnitude, number of indicators, and whether cross loadings or minor factors were included. The effectiveness of the thresholds varied across fit statistics, and was conditional on many features of the underlying model. Together, results suggest that conventional fit thresholds offer questionable utility in the context of IFA.

Physical fitness and associations with anthropometric measurements in 7 to 15-year-old school children.

PubMed

Andreasi, Viviane; Michelin, Edilaine; Rinaldi, Ana Elisa M; Burini, Roberto Carlos

2010-01-01

To analyze associations between health-related physical fitness and the anthropometric and demographic indicators of children at three elementary schools in Botucatu, SP, Brazil. The sample for this cross-sectional study was 988 elementary school students, recruited from the second to ninth grades (an age range of 7 to 15 years). The children underwent anthropometric assessment (weight, height, waist circumference and tricipital and subscapular skin folds) and were tested for health-related physical fitness (flexibility: sit and reach test; abdominal strength/stamina: 1-minute abdominal test; and aerobic stamina: 9-minute running/walking test). Data were analyzed using descriptive statistics plus Student's t test, the chi-square test or Fisher's exact test and logistic regression with a significance level of 5%. The physical fitness levels observed were significantly influenced by age (all levels), sex (abdominal strength/stamina), obesity (all levels), body adiposity (flexibility, abdominal strength/stamina) and abdominal adiposity (abdominal strength/stamina and aerobic stamina). Females were more prone to be unfit in abdominal strength/stamina. Both obesity and excessive abdominal adiposity predisposed children to be unfit in abdominal strength/stamina and aerobic stamina. Excess body adiposity increased the likelihood of poor trunk flexibility. Unhealthy physical fitness levels were related to female sex, obesity and excessive abdominal adiposity. Implementing programs designed to effect lifestyle changes to achieve physical fitness and healthy nutrition in these schools would meet the objectives of promoting healthy body weight and increased physical fitness among these schoolchildren.

Study of Factors Related to Army Delayed-Entry Program Attrition

DTIC Science & Technology

1985-11-01

level, gender , and tenure in DEP. Military classification and assignment are determined almost solely on cognitive factors, physical examinations...Between Gender and Responses to Question 13 for Voluntary DEP Losses . . . . . , . . . , . . . . o , o . ° . 99 P-2. Chi-square Tests for Independence...Between Gender and Responses to Question 13 for DHP Aooession/ Voluntary Active Duty Losses . . 9 0 4 . 0 0 0 0 a a 0 106 B-9. Chi-square Tests for

Anxiety, Depression and Hopelessness in Adolescents: A Structural Equation Model

PubMed Central

Cunningham, Shaylyn; Gunn, Thelma; Alladin, Assen; Cawthorpe, David

2008-01-01

Objective This study tested a structural model, examining the relationship between a latent variable termed demoralization and measured variables (anxiety, depression and hopelessness) in a community sample of Canadian youth. Methods The combined sample consisted of data collected from four independent studies from 2001 to 2005. Nine hundred and seventy one (n=971) participants were high school students (grades 10–12) from three geographic locations: Calgary, Saskatchewan and Lethbridge. Participants completed the Beck Anxiety Inventory (BAI), Beck Depression Inventory-Revised (BDI-II), Beck Hopelessness Scale (BHS), and demographic survey. Structural equation modeling was used for statistical analysis. Results The analysis revealed that the final model, including depression, anxiety and hopelessness and one latent variable demoralization, fit the data (chi-square value, X2 (2) = 7.25, p< .001, goodness of fit indices (CFI=0.99, NFI=0.98) and standardized error (0.05). Overall, the findings suggest that close relationships exist among depression, anxiety, hopelessness and demoralization that is stable across demographic variables. Further, the model explains the relationship between sub-clinical anxiety, depression and hopelessness. Conclusion These findings contribute to a theoretical framework, which has implications for educational and clinical intervention. The present findings will help guide further preventative research on examining demoralization as a precursor to sub-clinical anxiety and depression. PMID:18769644

Risk analysis in cohort studies with heterogeneous strata. A global chi2-test for dose-response relationship, generalizing the Mantel-Haenszel procedure.

PubMed

Ahlborn, W; Tuz, H J; Uberla, K

1990-03-01

In cohort studies the Mantel-Haenszel estimator ORMH is computed from sample data and is used as a point estimator of relative risk. Test-based confidence intervals are estimated with the help of the asymptotic chi-squared distributed MH-statistic chi 2MHS. The Mantel-extension-chi-squared is used as a test statistic for a dose-response relationship. Both test statistics--the Mantel-Haenszel-chi as well as the Mantel-extension-chi--assume homogeneity of risk across strata, which is rarely present. Also an extended nonparametric statistic, proposed by Terpstra, which is based on the Mann-Whitney-statistics assumes homogeneity of risk across strata. We have earlier defined four risk measures RRkj (k = 1,2,...,4) in the population and considered their estimates and the corresponding asymptotic distributions. In order to overcome the homogeneity assumption we use the delta-method to get "test-based" confidence intervals. Because the four risk measures RRkj are presented as functions of four weights gik we give, consequently, the asymptotic variances of these risk estimators also as functions of the weights gik in a closed form. Approximations to these variances are given. For testing a dose-response relationship we propose a new class of chi 2(1)-distributed global measures Gk and the corresponding global chi 2-test. In contrast to the Mantel-extension-chi homogeneity of risk across strata must not be assumed. These global test statistics are of the Wald type for composite hypotheses.(ABSTRACT TRUNCATED AT 250 WORDS)

Gender, mathematics, reading comprehension and science reasoning as predictors of science achievement among African-American students at a historical black college or university

NASA Astrophysics Data System (ADS)

Davis, Consuella Artiemese

This study investigated predictors that influence the science achievement of African-American non-science majors in a Physical Science class. The population consisted of male and female college students enrolled in Physical Science courses at a historical black college or university (HBCU) located in the southeastern portion of the United States. A personal data information sheet was administered to 120 participants during the Fall of 2008. The personal data information sheet consisted of questions pertaining to the high school courses, students took in math, language arts and science. It also consisted of basic background information. Students also gave written consent for their midterm and final grades earned in Physical Science to be used in the study as part of the analyses. A t-Test including chi-square tests revealed that there was not a significant difference in the raw scores of African-American females and African American males on the American College Test. A significant difference was not observed between the females and males on the ACT math subtest, t (118) = -.78, p = .43; reading comprehension subtest, t (118) = -1.44, .15 or on the science reasoning subtest, t (118) = -1.46, p = .15. A significant difference was not found between the final grades of African American females and the final grades of African American males. Chi-square tests were conducted to determine goodness of fit, X2 = 6.11, df = 1, p = .191. Although the grades of females were higher than males, results were not significant. The correlation between math ACT and final grades were not significant, r = .131, N = 120, p = .155, reading comprehension ACT and final grades were not significant, r = .072, N = 120, p = .434 and science reasoning ACT and final grades were found not to be significant, r = .109, N = 120, p = .237. Being that the majority of students who participated in the study were from one state, had similar high school backgrounds, had similar majors and were similar in age the sample had more homogeneity than difference. This may be the most plausible explanation for the results found in this study.

Assessing the fit of site-occupancy models

USGS Publications Warehouse

MacKenzie, D.I.; Bailey, L.L.

2004-01-01

Few species are likely to be so evident that they will always be detected at a site when present. Recently a model has been developed that enables estimation of the proportion of area occupied, when the target species is not detected with certainty. Here we apply this modeling approach to data collected on terrestrial salamanders in the Plethodon glutinosus complex in the Great Smoky Mountains National Park, USA, and wish to address the question 'how accurately does the fitted model represent the data?' The goodness-of-fit of the model needs to be assessed in order to make accurate inferences. This article presents a method where a simple Pearson chi-square statistic is calculated and a parametric bootstrap procedure is used to determine whether the observed statistic is unusually large. We found evidence that the most global model considered provides a poor fit to the data, hence estimated an overdispersion factor to adjust model selection procedures and inflate standard errors. Two hypothetical datasets with known assumption violations are also analyzed, illustrating that the method may be used to guide researchers to making appropriate inferences. The results of a simulation study are presented to provide a broader view of the methods properties.

California Wellness Study: American Indians and Obesity

PubMed Central

Hodge, Felicia Schanche; Kotkin-Jaszi, Suzanne T.

2011-01-01

This paper identifies the prevalence and predictors of obesity among California’s American Indian adults. A cross-sectional study was conducted at 13 rural sites. Indian healthcare clinics served as the sampling frame and were selected because of their proximity and access to the target population. Four-hundred and fifty adult American Indians participated; 74 percent were female and 26 percent were male. The average age was 40, ranging from 18–74. Measures included socio-demographics, general health, BMI, type 2 diabetes, exercise and dietary habits. Eighty-two percent were overweight, obese or morbidly obese. Chi-square tests revealed three variables significantly associated with BMI categories: having type 2 diabetes, female gender and poor general health status. A logistic regression model for obese/morbidly obese (BMI > 30) versus overweight/normal (BMI < 30) persons found gender and diabetes status as significant predictors, while general health status showed trend. Females had 1.59 greater odds of being obese than males (p=0.04). Those that do not have diabetes are less likely to be obese (p=0.02). Those that do not have good general health were 2.5 times more likely to be obese than those that have good general health (p=0.06). Overall goodness of fit was significant (p=0.0009). It is important to identify individuals and population who are normal/overweight, obese/morbidly obese so support and interventions can be planned and implemented. PMID:21625381

A Study of the Properties of a New Goodness-of-Fit Test

DTIC Science & Technology

1980-05-01

FANDOM STAEILIZEC STANDARD FORM 4LFH/S = 1.30, EET4 = 0,0 NIMEER OF HYPOTHESIS REJECTIONS IN 5000 REPLICATIONS 49 CHI SQU/RFD TFST 20 PTS 3C PTS 5C FT...51 240 PSSF 10? 2708 VS 5% 2043 N (0,1) 1? 1023 •CCNTRCL’ IS THE T EST OF UNIF0RM(0,1> VS UNIFORMED •RSSF* IS TFE FANDOM STAEILIZEQ STANDARD FORM ALPH

A Third Moment Adjusted Test Statistic for Small Sample Factor Analysis

PubMed Central

Lin, Johnny; Bentler, Peter M.

2012-01-01

Goodness of fit testing in factor analysis is based on the assumption that the test statistic is asymptotically chi-square; but this property may not hold in small samples even when the factors and errors are normally distributed in the population. Robust methods such as Browne’s asymptotically distribution-free method and Satorra Bentler’s mean scaling statistic were developed under the presumption of non-normality in the factors and errors. This paper finds new application to the case where factors and errors are normally distributed in the population but the skewness of the obtained test statistic is still high due to sampling error in the observed indicators. An extension of Satorra Bentler’s statistic is proposed that not only scales the mean but also adjusts the degrees of freedom based on the skewness of the obtained test statistic in order to improve its robustness under small samples. A simple simulation study shows that this third moment adjusted statistic asymptotically performs on par with previously proposed methods, and at a very small sample size offers superior Type I error rates under a properly specified model. Data from Mardia, Kent and Bibby’s study of students tested for their ability in five content areas that were either open or closed book were used to illustrate the real-world performance of this statistic. PMID:23144511

Determination of suitable drying curve model for bread moisture loss during baking

NASA Astrophysics Data System (ADS)

Soleimani Pour-Damanab, A. R.; Jafary, A.; Rafiee, S.

2013-03-01

This study presents mathematical modelling of bread moisture loss or drying during baking in a conventional bread baking process. In order to estimate and select the appropriate moisture loss curve equation, 11 different models, semi-theoretical and empirical, were applied to the experimental data and compared according to their correlation coefficients, chi-squared test and root mean square error which were predicted by nonlinear regression analysis. Consequently, of all the drying models, a Page model was selected as the best one, according to the correlation coefficients, chi-squared test, and root mean square error values and its simplicity. Mean absolute estimation error of the proposed model by linear regression analysis for natural and forced convection modes was 2.43, 4.74%, respectively.

Correcting Too Much or Too Little? The Performance of Three Chi-Square Corrections.

PubMed

Foldnes, Njål; Olsson, Ulf Henning

2015-01-01

This simulation study investigates the performance of three test statistics, T1, T2, and T3, used to evaluate structural equation model fit under non normal data conditions. T1 is the well-known mean-adjusted statistic of Satorra and Bentler. T2 is the mean-and-variance adjusted statistic of Sattertwaithe type where the degrees of freedom is manipulated. T3 is a recently proposed version of T2 that does not manipulate degrees of freedom. Discrepancies between these statistics and their nominal chi-square distribution in terms of errors of Type I and Type II are investigated. All statistics are shown to be sensitive to increasing kurtosis in the data, with Type I error rates often far off the nominal level. Under excess kurtosis true models are generally over-rejected by T1 and under-rejected by T2 and T3, which have similar performance in all conditions. Under misspecification there is a loss of power with increasing kurtosis, especially for T2 and T3. The coefficient of variation of the nonzero eigenvalues of a certain matrix is shown to be a reliable indicator for the adequacy of these statistics.

[Development of a presenteeism questionnaire for skilled workers at high-technology enterprises].

PubMed

Sheng, Li; Huang, Jian-Shi; He, Lian; Cui, Jian-Xia; Xie, Jing; Liu, Feng-Juan

2009-08-01

To develop a presenteeism questionnaire for Chinese high-technology skilled workers. Methods being used would include literature review, face-to-face in depth interview, experts' consultation in developing the questionnaire. The presenteeism questionnaire includes two sections;one on employee's general health condition and the second one is a survey on the influences of employees'health conditions on their productivity. The first section includes 55 terms and 8 dimensionalities as below: Ache, Symptoms, Sleeping problem, Attention, Bad emotion, Pressure, Fatigue, Social adapting. These dimensionalities Cronbach's alpha are 0.79, 0.83, 0.75, 0.69, 0.83, 0.86, 0.80, 0.88 respectively and their half Spearman-Browns are 0.78, 0.75, 0.61, 0.62, 0.82, 0.81, 0.77, 0.88, respectively. Goodness of fit test model indices are as below: chi(2)/df -3.68, normed fit index 0.95, non-normed fit index 0.96, compatative fit index 0.96, standardized root mean residual 0.05, root mean square error of approximation 0.05. The relate-coefficient with SF-36 is 0.55. 42.77% of employees having received the survey, claim that their health problem do not influence their productivity, and 55.72% of them claiming that their productivity are reduced to 50%-90% because of their health problems while another 1.51% of them claim that their productivity reduced more than 50%. 84.5% of the interviewees claim that they have never been absent at work because of health problems, and 15.3% of them claim that their total hours of absence are between 0 and 100. Only 0.2% of the workers claim that the total hours of absence are more than 100. The developed presenteeism shows good reliability and higher validity, so can be used to measure the presenteeism of skilled workers working at high-technology enterprises.

A Comparison of Latent Growth Models for Constructs Measured by Multiple Items

ERIC Educational Resources Information Center

Leite, Walter L.

2007-01-01

Univariate latent growth modeling (LGM) of composites of multiple items (e.g., item means or sums) has been frequently used to analyze the growth of latent constructs. This study evaluated whether LGM of composites yields unbiased parameter estimates, standard errors, chi-square statistics, and adequate fit indexes. Furthermore, LGM was compared…

Monte Carlo analysis for the determination of the conic constant of an aspheric micro lens based on a scanning white light interferometric measurement

NASA Astrophysics Data System (ADS)

Gugsa, Solomon A.; Davies, Angela

2005-08-01

Characterizing an aspheric micro lens is critical for understanding the performance and providing feedback to the manufacturing. We describe a method to find the best-fit conic of an aspheric micro lens using a least squares minimization and Monte Carlo analysis. Our analysis is based on scanning white light interferometry measurements, and we compare the standard rapid technique where a single measurement is taken of the apex of the lens to the more time-consuming stitching technique where more surface area is measured. Both are corrected for tip/tilt based on a planar fit to the substrate. Four major parameters and their uncertainties are estimated from the measurement and a chi-square minimization is carried out to determine the best-fit conic constant. The four parameters are the base radius of curvature, the aperture of the lens, the lens center, and the sag of the lens. A probability distribution is chosen for each of the four parameters based on the measurement uncertainties and a Monte Carlo process is used to iterate the minimization process. Eleven measurements were taken and data is also chosen randomly from the group during the Monte Carlo simulation to capture the measurement repeatability. A distribution of best-fit conic constants results, where the mean is a good estimate of the best-fit conic and the distribution width represents the combined measurement uncertainty. We also compare the Monte Carlo process for the stitched data and the not stitched data. Our analysis allows us to analyze the residual surface error in terms of Zernike polynomials and determine uncertainty estimates for each coefficient.

The Essential Resilience Scale: Instrument Development and Prediction of Perceived Health and Behaviour.

PubMed

Chen, Xinguang; Wang, Yan; Yan, Yaqiong

2016-12-01

Further advancement in stress and health research calls for better tools to assess resilience. In this study, we developed the Essential Resilience Scale (ERS) and investigated the association between ERS scores and several health and behaviour measures. We developed the ERS with an operationalized definition of resilience-an individual's capability to anticipate, be flexible with and bounce back from three types of traumatic and adverse events (physical, emotional and social). The 15-item ERS was assessed using survey data from a diverse sample (n = 238, aged 18-45 years, 76 rural-to-urban migrants, 85 rural residents, 77 urban residents) recruited in Wuhan, China. Results showed a high reliability of the ERS (α = 0.94). Confirmatory factor analysis demonstrated a satisfactory fit of the proposed second-order ERS measurement model (goodness-of-fit index = 0.94, comparative fit index = 0.98, root mean square error of approximation = 0.06, chi-square/df = 1.75). Multivariate regression analysis indicated that ERS scores significantly predicted perceived health status, stress, anxiety, depression and cigarette smoking after controlling for important covariates. Findings of this study indicate high reliability and validity of the scale and its potential use in advancing stress and health research. Further studies are implied to provide additional support for the ERS and its relations with other health outcomes. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Improvements in Spectrum's fit to program data tool.

PubMed

Mahiane, Severin G; Marsh, Kimberly; Grantham, Kelsey; Crichlow, Shawna; Caceres, Karen; Stover, John

2017-04-01

The Joint United Nations Program on HIV/AIDS-supported Spectrum software package (Glastonbury, Connecticut, USA) is used by most countries worldwide to monitor the HIV epidemic. In Spectrum, HIV incidence trends among adults (aged 15-49 years) are derived by either fitting to seroprevalence surveillance and survey data or generating curves consistent with program and vital registration data, such as historical trends in the number of newly diagnosed infections or people living with HIV and AIDS related deaths. This article describes development and application of the fit to program data (FPD) tool in Joint United Nations Program on HIV/AIDS' 2016 estimates round. In the FPD tool, HIV incidence trends are described as a simple or double logistic function. Function parameters are estimated from historical program data on newly reported HIV cases, people living with HIV or AIDS-related deaths. Inputs can be adjusted for proportions undiagnosed or misclassified deaths. Maximum likelihood estimation or minimum chi-squared distance methods are used to identify the best fitting curve. Asymptotic properties of the estimators from these fits are used to estimate uncertainty. The FPD tool was used to fit incidence for 62 countries in 2016. Maximum likelihood and minimum chi-squared distance methods gave similar results. A double logistic curve adequately described observed trends in all but four countries where a simple logistic curve performed better. Robust HIV-related program and vital registration data are routinely available in many middle-income and high-income countries, whereas HIV seroprevalence surveillance and survey data may be scarce. In these countries, the FPD tool offers a simpler, improved approach to estimating HIV incidence trends.

A Geomagnetic Estimate of Mean Paleointensity

NASA Technical Reports Server (NTRS)

Voorhies, Coerte V.

2004-01-01

To test a statistical hypothesis about Earth's magnetic field against paleomagnetism, the present field is used to estimate time averaged paleointensity. The estimate used the modern magnetic multipole spectrum R(n), which gives the mean square induction represented by spherical harmonics of degree n averaged over the sphere of radius a = 6371.2 km. The hypothesis asserts that low degree multi-pole powers of the coresource field are distributed as chi-squared with 2n+1 degrees of freedom and expectation values, where c is the 3480 km radius of the Earth's core. (This is compatible with a usually mainly geocentric axial dipolar field). Amplitude K is estimated by fitting theoretical to observational spectra through degree 12. The resulting calibrated expectation spectrum is summed through degree 12 to estimate expected square intensity F(exp 2). The sum also estimates F(exp 2) averaged over geologic time, in so far as the present magnetic spectrum is a fair sample of that generated in the past by core geodynamic processes. Additional information is included in the original extended abstract.

Deriving sulfamethoxazole dissipation endpoints in pasture soils using first order and biphasic kinetic models.

PubMed

Srinivasan, Prakash; Sarmah, Ajit K; Rohan, Maheswaran

2014-08-01

Single first-order (SFO) kinetic model is often used to derive the dissipation endpoints of an organic chemical in soil. This model is used due to its simplicity and requirement by regulatory agencies. However, using the SFO model for all types of decay pattern could lead to under- or overestimation of dissipation endpoints when the deviation from first-order is significant. In this study the performance of three biphasic kinetic models - bi-exponential decay (BEXP), first-order double exponential decay (FODED), and first-order two-compartment (FOTC) models was evaluated using dissipation datasets of sulfamethoxazole (SMO) antibiotic in three different soils under varying concentration, depth, temperature, and sterile conditions. Corresponding 50% (DT50) and 90% (DT90) dissipation times for the antibiotics were numerically obtained and compared against those obtained using the SFO model. The fit of each model to the measured values was evaluated based on an array of statistical measures such as coefficient of determination (R(2)adj), root mean square error (RMSE), chi-square (χ(2)) test at 1% significance, Bayesian Information Criteria (BIC) and % model error. Box-whisker residual plots were also used to compare the performance of each model to the measured datasets. The antibiotic dissipation was successfully predicted by all four models. However, the nonlinear biphasic models improved the goodness-of-fit parameters for all datasets. Deviations from datasets were also often less evident with the biphasic models. The fits of FOTC and FODED models for SMO dissipation datasets were identical in most cases, and were found to be superior to the BEXP model. Among the biphasic models, the FOTC model was found to be the most suitable for obtaining the endpoints and could provide a mechanistic explanation for SMO dissipation in the soils. Copyright © 2014 Elsevier B.V. All rights reserved.

Factors affecting access to head and neck cancer care after a natural disaster: a post-Hurricane Katrina survey.

PubMed

Loehn, Bridget; Pou, Anna M; Nuss, Daniel W; Tenney, Justin; McWhorter, Andrew; DiLeo, Michael; Kakade, Anagha C; Walvekar, Rohan R

2011-01-01

Our aim was to survey the factors affecting access to cancer care in patients with head and neck cancer after Hurricane Katrina. In this cross-sectional survey, 207 patients with head and neck cancer were identified post-Hurricane Katrina, but only 83 patients completed the questionnaires and were analyzed. Clinical, demographic, and socioeconomic data were recorded. Chi-square test and t test were used for comparisons. Patients who felt that there was a lack of access to cancer care would have sought treatment earlier had they had better access to cancer care (chi-square[1] = 32; p < .0001). Patients who felt that there was a lack of access to cancer care also had difficulty receiving treatment (chi-square[1] = 48; p < .0001). Availability of transportation affected access to cancer care in patients with early-stage cancers (chi-square[1] = 4; p < .035). In the postdisaster environment, patients who felt the lack of access to cancer care post-Hurricane Katrina would have sought treatment earlier with better access to cancer care. These patients also reported difficulty obtaining cancer treatment. Availability of transportation affected access to cancer care in patients with early-stage cancers. Clinical, demographic, and socioeconomic factors did not influence access to cancer care. © 2010 Wiley Periodicals, Inc. Head Neck, 2011.

Linearised and non-linearised isotherm models optimization analysis by error functions and statistical means

PubMed Central

2014-01-01

In adsorption study, to describe sorption process and evaluation of best-fitting isotherm model is a key analysis to investigate the theoretical hypothesis. Hence, numerous statistically analysis have been extensively used to estimate validity of the experimental equilibrium adsorption values with the predicted equilibrium values. Several statistical error analysis were carried out. In the present study, the following statistical analysis were carried out to evaluate the adsorption isotherm model fitness, like the Pearson correlation, the coefficient of determination and the Chi-square test, have been used. The ANOVA test was carried out for evaluating significance of various error functions and also coefficient of dispersion were evaluated for linearised and non-linearised models. The adsorption of phenol onto natural soil (Local name Kalathur soil) was carried out, in batch mode at 30 ± 20 C. For estimating the isotherm parameters, to get a holistic view of the analysis the models were compared between linear and non-linear isotherm models. The result reveled that, among above mentioned error functions and statistical functions were designed to determine the best fitting isotherm. PMID:25018878

FIREFLY (Fitting IteRativEly For Likelihood analYsis): a full spectral fitting code

NASA Astrophysics Data System (ADS)

Wilkinson, David M.; Maraston, Claudia; Goddard, Daniel; Thomas, Daniel; Parikh, Taniya

2017-12-01

We present a new spectral fitting code, FIREFLY, for deriving the stellar population properties of stellar systems. FIREFLY is a chi-squared minimization fitting code that fits combinations of single-burst stellar population models to spectroscopic data, following an iterative best-fitting process controlled by the Bayesian information criterion. No priors are applied, rather all solutions within a statistical cut are retained with their weight. Moreover, no additive or multiplicative polynomials are employed to adjust the spectral shape. This fitting freedom is envisaged in order to map out the effect of intrinsic spectral energy distribution degeneracies, such as age, metallicity, dust reddening on galaxy properties, and to quantify the effect of varying input model components on such properties. Dust attenuation is included using a new procedure, which was tested on Integral Field Spectroscopic data in a previous paper. The fitting method is extensively tested with a comprehensive suite of mock galaxies, real galaxies from the Sloan Digital Sky Survey and Milky Way globular clusters. We also assess the robustness of the derived properties as a function of signal-to-noise ratio (S/N) and adopted wavelength range. We show that FIREFLY is able to recover age, metallicity, stellar mass, and even the star formation history remarkably well down to an S/N ∼ 5, for moderately dusty systems. Code and results are publicly available.1

Group Influences on Young Adult Warfighters’ Risk Taking

DTIC Science & Technology

2016-12-01

Statistical Analysis Latent linear growth models were fitted using the maximum likelihood estimation method in Mplus (version 7.0; Muthen & Muthen...condition had a higher net score than those in the alone condition (b = 20.53, SE = 6.29, p < .001). Results of the relevant statistical analyses are...8.56 110.86*** 22.01 158.25*** 29.91 Model fit statistics BIC 4004.50 5302.539 5540.58 Chi-square (df) 41.51*** (16) 38.10** (20) 42.19** (20

40 CFR 89.322 - Carbon dioxide analyzer calibration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Test Equipment Provisions § 89.322 Carbon dioxide analyzer calibration. (a) Prior to its introduction... requirements of paragraph (a)(3) of this section. Proceed as follows: (1) Follow good engineering practices for... engineering practice. For each range calibrated, if the deviation from a least-squares best-fit straight line...

Recurrent pain and discomfort in relation to fitness and physical activity among young school children.

PubMed

Sollerhed, Ann-Christin; Andersson, Ingemar; Ejlertsson, Göran

2013-01-01

As an increase in pain symptoms among children has been shown in the last decades, the aim of this study was to describe perceptions of recurrent pain, measured physical fitness and levels of reported physical activity (PA) in children, and to investigate if any associations between PA, fitness and recurrent pain could be identified. A school-based study comprised 206 Swedish children 8-12 years old, 114 boys, 92 girls. A questionnaire with questions about perceived pain, self-reported PA and lifestyle factors was used. Health-related fitness was assessed by 11 physical tests. A physical index was calculated from these tests as a z score. High physical index indicated high fitness and low physical index indicated low fitness. ANOVA test, chi-square test and logistic regression analysis were used to compare active and inactive children. The prevalence of one pain location (head, abdomen or back) was 26%, two 11% and three 4% (n=206). Female gender, living in single-parent families, low PA and low subjective health were associated with reported recurrent pain. Children reporting high levels of PA had high physical index and reported low prevalence of pain symptoms. The physical index and level of self-reported PA decreased gradually the more pain locations. Physically active children had higher fitness levels and reported less pain symptoms than inactive peers. Coping with pain is an integral part of PA, and active children learn to cope with unpleasant body sensations which together with high fitness may reduce the perception of pain.

Re-calibration of coronary risk prediction: an example of the Seven Countries Study.

PubMed

Puddu, Paolo Emilio; Piras, Paolo; Kromhout, Daan; Tolonen, Hanna; Kafatos, Anthony; Menotti, Alessandro

2017-12-14

We aimed at performing a calibration and re-calibration process using six standard risk factors from Northern (NE, N = 2360) or Southern European (SE, N = 2789) middle-aged men of the Seven Countries Study, whose parameters and data were fully known, to establish whether re-calibration gave the right answer. Greenwood-Nam-D'Agostino technique as modified by Demler (GNDD) in 2015 produced chi-squared statistics using 10 deciles of observed/expected CHD mortality risk, corresponding to Hosmer-Lemeshaw chi-squared employed for multiple logistic equations whereby binary data are used. Instead of the number of events, the GNDD test uses survival probabilities of observed and predicted events. The exercise applied, in five different ways, the parameters of the NE-predictive model to SE (and vice-versa) and compared the outcome of the simulated re-calibration with the real data. Good re-calibration could be obtained only when risk factor coefficients were substituted, being similar in magnitude and not significantly different between NE-SE. In all other ways, a good re-calibration could not be obtained. This is enough to praise for an overall need of re-evaluation of most investigations that, without GNDD or another proper technique for statistically assessing the potential differences, concluded that re-calibration is a fair method and might therefore be used, with no specific caution.

Can the Presence of Crystalluria Predict Stone Formation in Patients with Cystinuria?

PubMed

Wong, Kathie A; Pardy, Caroline; Pillay, Soma; Athanasiou, Thanos; Rottenberg, Giles; Bultitude, Matthew; Chandra, Ashish; Thomas, Kay

2016-05-01

To determine the feasibility of crystalluria as a biomarker for stone disease in patients with cystinuria. All patients attending a multidisciplinary cystinuria clinic provided early morning urine (EMU) and clinic urine (CU) samples for crystal measurement over a 2-year period (August 1, 2010, to July 31, 2012). Association between presence of crystals, presence of stone(s), and new stone growth (NSG) was determined using the chi-square test. Crystal numbers in EMU and CU were compared in patients with stones/NSG and no stones/stable disease using the Mann-Whitney U test. There was a statistically significant difference between the presence of crystalluria and presence of stones for CU (chi-square test = 5.86, df = 1, p = 0.02) but not EMU (chi-square test = 1.92, df = 1, p = 0.17) and between the presence of crystalluria and NSG for CU (chi-square test = 8.10, df = 1, p = 0.004) but not EMU (chi-square test = 1.32, df = 1, p = 0.25). Patients with stones and NSG have higher levels of crystalluria in CU than patients with no stones or stable disease (stones, median = 41, interquartile range [IQR] = 600 vs median = 0, IQR = 21, p = 0.01; NSG, median = 49, IQR = 525 vs median = 0, IQR = 40, p = 0.01). The presence of crystalluria in CU samples is associated with the presence of stones. Crystalluria is comparable to ultrasound and may serve as a useful adjunct to predict whether a patient with cystinuria has stones, which could guide the frequency of clinic review and imaging.

Performance of Transit Model Fitting in Processing Four Years of Kepler Science Data

NASA Astrophysics Data System (ADS)

Li, Jie; Burke, Christopher J.; Jenkins, Jon Michael; Quintana, Elisa V.; Rowe, Jason; Seader, Shawn; Tenenbaum, Peter; Twicken, Joseph D.

2014-06-01

We present transit model fitting performance of the Kepler Science Operations Center (SOC) Pipeline in processing four years of science data, which were collected by the Kepler spacecraft from May 13, 2009 to May 12, 2013. Threshold Crossing Events (TCEs), which represent transiting planet detections, are generated by the Transiting Planet Search (TPS) component of the pipeline and subsequently processed in the Data Validation (DV) component. The transit model is used in DV to fit TCEs and derive parameters that are used in various diagnostic tests to validate planetary candidates. The standard transit model includes five fit parameters: transit epoch time (i.e. central time of first transit), orbital period, impact parameter, ratio of planet radius to star radius and ratio of semi-major axis to star radius. In the latest Kepler SOC pipeline codebase, the light curve of the target for which a TCE is generated is initially fitted by a trapezoidal model with four parameters: transit epoch time, depth, duration and ingress time. The trapezoidal model fit, implemented with repeated Levenberg-Marquardt minimization, provides a quick and high fidelity assessment of the transit signal. The fit parameters of the trapezoidal model with the minimum chi-square metric are converted to set initial values of the fit parameters of the standard transit model. Additional parameters, such as the equilibrium temperature and effective stellar flux of the planet candidate, are derived from the fit parameters of the standard transit model to characterize pipeline candidates for the search of Earth-size planets in the Habitable Zone. The uncertainties of all derived parameters are updated in the latest codebase to take into account for the propagated errors of the fit parameters as well as the uncertainties in stellar parameters. The results of the transit model fitting of the TCEs identified by the Kepler SOC Pipeline, including fitted and derived parameters, fit goodness metrics and diagnostic figures, are included in the DV report and one-page report summary, which are accessible by the science community at NASA Exoplanet Archive. Funding for the Kepler Mission has been provided by the NASA Science Mission Directorate.

Aging and quality of life of elderly people in rural areas.

PubMed

Garbaccio, Juliana Ladeira; Tonaco, Luís Antônio Batista; Estêvão, Wilson Goulart; Barcelos, Bárbara Jacome

2018-01-01

To evaluate the quality of life and health of elderly in rural areas of Minas Gerais State's center-west. Cross-sectional study, in four municipalities of Minas Gerais State, by interviewing elderly people. Associations between socio-demographic and quality of life variables were tested, separated into "satisfactory"/"unsatisfactory" with values from the median of positive answers. It was used the chi-square test, Fisher's test and regression. 182 elderly answered the questions and showed a relation with the "satisfactory" quality of life - bivariate (p < 0.05): age by 69 years (61.6%), married (61.7%), living by 54 years in rural areas (68%), with no financial support (59.5%), living with someone else (61%), non-smoker (60%), presenting good health (76.7%), satisfied with life (69.6%); regression: not having financial support, living with someone else and not smoking. Elderly people in rural areas present good quality of life/health in the cognitive aspect, access to services, goods, habits, but awareness must be constant due to their weakness.

An analysis of the positional distribution of DNA motifs in promoter regions and its biological relevance.

PubMed

Casimiro, Ana C; Vinga, Susana; Freitas, Ana T; Oliveira, Arlindo L

2008-02-07

Motif finding algorithms have developed in their ability to use computationally efficient methods to detect patterns in biological sequences. However the posterior classification of the output still suffers from some limitations, which makes it difficult to assess the biological significance of the motifs found. Previous work has highlighted the existence of positional bias of motifs in the DNA sequences, which might indicate not only that the pattern is important, but also provide hints of the positions where these patterns occur preferentially. We propose to integrate position uniformity tests and over-representation tests to improve the accuracy of the classification of motifs. Using artificial data, we have compared three different statistical tests (Chi-Square, Kolmogorov-Smirnov and a Chi-Square bootstrap) to assess whether a given motif occurs uniformly in the promoter region of a gene. Using the test that performed better in this dataset, we proceeded to study the positional distribution of several well known cis-regulatory elements, in the promoter sequences of different organisms (S. cerevisiae, H. sapiens, D. melanogaster, E. coli and several Dicotyledons plants). The results show that position conservation is relevant for the transcriptional machinery. We conclude that many biologically relevant motifs appear heterogeneously distributed in the promoter region of genes, and therefore, that non-uniformity is a good indicator of biological relevance and can be used to complement over-representation tests commonly used. In this article we present the results obtained for the S. cerevisiae data sets.

COX-2 verexpression in pretreatment biopsies predicts response of rectal cancers to neoadjuvant radiochemotherapy

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

Smith, Fraser M.; Reynolds, John V.; Kay, Elaine W.

2006-02-01

Purpose: To determine the utility of COX-2 expression as a response predictor for patients with rectal cancer who are undergoing neoadjuvant radiochemotherapy (RCT). Methods and Materials: Pretreatment biopsies (PTB) from 49 patients who underwent RCT were included. COX-2 and proliferation in PTB were assessed by immunohistochemistry (IHC) and apoptosis was detected by TUNEL stain. Response to treatment was assessed by a 5-point tumor-regression grade (TRG) based on the ratio of residual tumor to fibrosis. Results: Good response (TRG 1 + 2), moderate response (TRG 3), and poor response (TRG 4 + 5) were seen in 21 patients (42%), 11 patientsmore » (22%), and 17 patients (34%), respectively. Patients with COX-2 overexpression in PTB were more likely to demonstrate moderate or poor response (TRG 3 + 4) to treatment than were those with normal COX-2 expression (p = 0.026, chi-square test). Similarly, poor response was more likely if patients had low levels of spontaneous apoptosis in PTBs (p = 0.0007, chi-square test). Conclusions: COX-2 overexpression and reduced apoptosis in PTB can predict poor response of rectal cancer to RCT. As COX-2 inhibitors are commercially available, their administration to patients who overexpress COX-2 warrants assessment in clinical trials in an attempt to increase overall response rates.« less

Knowledge of risk factors and early detection methods and practices towards breast cancer among nurses in Indira Gandhi Medical College, Shimla, Himachal Pradesh, India.

PubMed

Fotedar, Vikas; Seam, Rajeev K; Gupta, Manoj K; Gupta, Manish; Vats, Siddharth; Verma, Sunita

2013-01-01

Breast cancer is an increasing health problem in India. Screening for early detection should lead to a reduction in mortality from the disease. It is known that motivation by nurses influences uptake of screening methods by women. This study aimed to investigate knowledge of breast cancer risk factors and early detection methods and the practice of screening among nurses in Indira Gandhi Medical College, Shimla, Himachal Pradesh. A cross-sectional study was conducted using a self-administered questionnaire to assess the knowledge of breast cancer risk factors, early detection methods and practice of screening methods among 457 nurses working in an Indira Gandhi Medical College, Shimla-H.P. Chi square test, Data was analysed using SPSS version 16. Test of significance used was chi square test. The response rate of the study was 94.9%. The average knowledge of risk factors about breast cancer of the entire population is 49%. 10.5% of nurses had poor knowledge, 25.2% of the nurses had good knowledge, 45% had very good knowledge and 16.3% of the nurses had excellent knowledge about risk factors of breast cancer and early detection methods. The knowledge level was significantly higher among BSC nurses than nurses with Diploma. 54% of participants in this study reportedly practice BSE at least once every year. Less than one-third reported that they had CBE within the past one year. 7% ever had mammogram before this study. Results from this study suggest the frequent continuing medical education programmes on breast cancer at institutional level is desirable.

Hispanic ethnicity and Caucasian race: Relations with posttraumatic stress disorder's factor structure in clinic-referred youth.

PubMed

Contractor, Ateka A; Claycomb, Meredith A; Byllesby, Brianna M; Layne, Christopher M; Kaplow, Julie B; Steinberg, Alan M; Elhai, Jon D

2015-09-01

The severity of posttraumatic stress disorder (PTSD) symptoms is linked to race and ethnicity, albeit with contradictory findings (reviewed in Alcántara, Casement, & Lewis-Fernández, 2013; Pole, Gone, & Kulkarni, 2008). We systematically examined Caucasian (n = 3,767) versus non-Caucasian race (n = 2,824) and Hispanic (n = 2,395) versus non-Hispanic ethnicity (n = 3,853) as candidate moderators of PTSD's 5-factor model structural parameters (Elhai et al., 2013). The sample was drawn from the National Child Traumatic Stress Network's Core Data Set, currently the largest national data set of clinic-referred children and adolescents exposed to potentially traumatic events. Using confirmatory factor analysis, we tested the invariance of PTSD symptom structural parameters by race and ethnicity. Chi-square difference tests and goodness-of-fit values showed statistical equivalence across racial and ethnic groups in the factor structure of PTSD and in mean item-level indicators of PTSD symptom severity. Results support the structural invariance of PTSD's 5-factor model across the compared racial and ethnic groups. Furthermore, results indicated equivalent item-level severity across racial and ethnic groups; this supports the use of item-level comparisons across these groups. (c) 2015 APA, all rights reserved).

Ensuring Positiveness of the Scaled Difference Chi-square Test Statistic.

PubMed

Satorra, Albert; Bentler, Peter M

2010-06-01

A scaled difference test statistic [Formula: see text] that can be computed from standard software of structural equation models (SEM) by hand calculations was proposed in Satorra and Bentler (2001). The statistic [Formula: see text] is asymptotically equivalent to the scaled difference test statistic T̄(d) introduced in Satorra (2000), which requires more involved computations beyond standard output of SEM software. The test statistic [Formula: see text] has been widely used in practice, but in some applications it is negative due to negativity of its associated scaling correction. Using the implicit function theorem, this note develops an improved scaling correction leading to a new scaled difference statistic T̄(d) that avoids negative chi-square values.

Psychometric Testing of the Persian Version of the Perceived Perioperative Competence Scale-Revised.

PubMed

Ajorpaz, Neda Mirbagher; Tafreshi, Mansoureh Zagheri; Mohtashami, Jamileh; Zayeri, Farid; Rahemi, Zahra

2017-12-01

The clinical competence of nursing students in operating room (OR) is an important issue in nursing education. The purpose of this study was to evaluate the psychometric properties of the Persian Perceived Perioperative Competence Scale-Revised (PPCS-R) instrument. This cross-sectional study was conducted across 12 universities in Iran. The psychometric properties and factor structure of the PPCS-R for OR students was examined. Based on the results of factor analysis, seven items were removed from the original version of the scale. The fitness indices of the Persian scale include comparative fit index (CFI) = .90, goodness-of-fit-index (GFI) = .86, adjusted goodness-of-fit index (AGFI) = .90, normed fit index (NFI) = .84, and root mean square error of approximation (RMSEA) = .04. High validity and reliability indicated the scale's value for measuring perceived perioperative competence of Iranian OR students.

Effect of drying conditions on drying kinetics and quality of aromatic Pandanus amaryllifolius leaves.

PubMed

Rayaguru, Kalpana; Routray, Winny

2010-12-01

Pandanus amaryllifolius is a plant with aromatic leaves, which impart the characteristic flavour of aromatic rice. The quality of aromatic Pandanus leaves dried at low temperature (35 °C) and low RH (27%) in a heat pump dryer was evaluated and compared with those obtained from hot air drying at 45 °C. Thin-layer drying kinetics has been studied for both the conditions. To determine the kinetic parameters, the drying data were fitted to various semi-theoretical models. The goodness of fit was determined using the coefficient of determination, reduced chi square, and root mean square error. Aroma, colour, and overall acceptability determination of fresh and dried leaves were made using sensory evaluation. Drying of leaves took place mainly under the falling-rate period. The Page equation was found to be best among the proposed models to describe the thin-layer drying of Pandanus leaves with higher coefficient of determination. The effective moisture diffusivity values were also determined. The effect of low RH was prominent during the initial drying when the product was moist. The effect of temperature was prominent in the later part of drying, which acted as a driving force for moisture diffusion and hence the total drying time was reduced. Retention of aromatic compound 2-acetyl-1-pyrroline content was more in low temperature dried samples with higher sensory scores.

Examining the Affordances of Dual Cognitive Processing to Explain the Development of High School Students' Nature of Science Views

NASA Astrophysics Data System (ADS)

Jackson, Luke M.

This mixed method study was aimed at examining the influence of dual processing (Type 1 and Type 2 thinking) on the development of high school students' nature of science (NOS) views. Type 1 thinking is intuitive, experiential, and heuristic. Type 2 thinking is rational, analytical, and explicit. Three research questions were asked: (1) Do the experiential process (Type 1) and the logical process (Type 2) influence the development of students' NOS views? (2) If there is an influence on students' NOS views, then what is the nature of relationship between the experiential process (Type 1) and the development of NOS views? (3) What is the nature of relationship between the logical process (Type 2) and the development of NOS views? The Views of Nature of Science Questionnaire C (VNOS-C; Lederman, Abd-El-Khalick, Bell, & Schwartz, 2002) was administered to 29 high school students at the beginning and at the end of an explicit-reflective NOS intervention offered in an Advanced Placement environmental science course. Changes in students' NOS views were calculated through a chi-square test and examining the percentage of students holding NOS views at various levels of sophistication. With the chi-square goodness of fit test performed, the relationship between pre and post NOS scores was not significant, X2(3, 29) = 4.78, p <.05. The informed and preinformed NOS views increased (14%, 17%) in frequency while the mixed and uninformed NOS views decreased (i.e. improved 26%, 24%) in frequency from pre to posttest. The reading discussions were coded based on the EBR framework (Furtak et al., 2010) to analyze the use of dual processing. Type1 and Type 2 thinking were both used during the intervention and reading reflections. Type 2 thinking was more prominent when analyzing a problem, formulating a hypothesis, or stating logical claims. The association of NOS education and Type 1 and Type 2 thinking in scientific literacy was examined, and implications and future research are discussed.

Parametrization of electron impact ionization cross sections for CO, CO2, NH3 and SO2

NASA Technical Reports Server (NTRS)

Srivastava, Santosh K.; Nguyen, Hung P.

1987-01-01

The electron impact ionization and dissociative ionization cross section data of CO, CO2, CH4, NH3, and SO2, measured in the laboratory, were parameterized utilizing an empirical formula based on the Born approximation. For this purpose an chi squared minimization technique was employed which provided an excellent fit to the experimental data.

Financial Capability and Sociodemographic Factors among Survivors of Human Trafficking.

PubMed

Okech, David; McGarity, Stephen Vandiver; Hansen, Nathan; Burns, Abigail C; Howard, Waylon

2018-01-01

Improving the economic well-being of the girls and women is a key to reducing re-trafficking and in providing stability that survivors can use to rebuild their lives. The study looks at how various sociodemographic traits affected the financial capability of n = 144 women and girls who received intervention at a residential care facility in Ghana, West Africa. Three domain of financial capability are assessed in this, i.e., financial risk, financial planning, and financial saving. A scaled likelihood ratio test (chi-square difference test) was used to evaluate the significance of each direct covariate effect(%). Each of the overall goodness-of-fit indices suggested that the initial CFA model fit the data well, χ 2 (19, N = 144)  = 31.45, p = 0.04, RMSEA = 0.067 (90% CI: 0.017-0.108), TLI = 0.923, CFI = 0.948. Older women reported lower levels of financial savings than younger women. We found that women with secondary school education or higher reported significantly higher financial risk than women with less education. Women with children reported lower levels of financial saving than women without children. Married women indicated significantly more financial saving than single women. There was a significant negative effect of time spent in trafficking conditions on financial saving, indicating the highest average level of financial savings at intervention and decreased thereafter. Programs and policies in resource-scarce contexts that aim to assist trafficking survivors must go beyond providing psychosocial counseling and focus also on economic development opportunities.

Imipenem Resistant Pseudomonas aeruginosa: The fall of the final quarterback.

PubMed

Ameen, Nadya; Memon, Zahida; Shaheen, Shehla; Fatima, Ghulam; Ahmed, Farah

2015-01-01

To isolate, determine the frequency, and study the demographic trends of MBL positive Pseudomonas aeruginosa from imipenem resistant isolates collected from clinical samples in a tertiary care hospital of Pakistan. In this cross sectional study a total of 230 strains of Pseudomonas were isolated from various clinical specimens on the basis of culture and biochemical tests. Imipenem resistant isolates were selected by Kirby Bauer Diffusion technique, followed by screening for MBL production by Imipenem EDTA Combined Disk Test. Demographic details of each patient were recorded on a separate questionnaire. Chi-Square goodness-of-fit test was computed to review the isolation of MBL positive isolates (P-value ≤ 0.05) in different specimen. Out of 230 strains of P. aeruginosa 49.5% were imipenem resistant; MBL production was confirmed in 64.9% of the resistant isolates. Resistance to polymyxin B (12.5%) was notable. Majority of the MBL positive strains were isolated from patients aged between 20-39 years (45.9%) and the predominant source was pus (43.24%) which was found to be statistically significant (P-value=0.04). Outpatient departments (24.3%) and burn unit (21.6%) were the major places for resistant isolates. MBL production is one of the major causes of IRPA. Increasing resistance to polymyxin B is grave. Due to acquisition of MBL strains MDR P. aeruginosa has become endemic in tertiary setups.

Imipenem Resistant Pseudomonas aeruginosa: The fall of the final quarterback

PubMed Central

Ameen, Nadya; Memon, Zahida; Shaheen, Shehla; Fatima, Ghulam; Ahmed, Farah

2015-01-01

Objective: To isolate, determine the frequency, and study the demographic trends of MBL positive Pseudomonas aeruginosa from imipenem resistant isolates collected from clinical samples in a tertiary care hospital of Pakistan. Methods: In this cross sectional study a total of 230 strains of Pseudomonas were isolated from various clinical specimens on the basis of culture and biochemical tests. Imipenem resistant isolates were selected by Kirby Bauer Diffusion technique, followed by screening for MBL production by Imipenem EDTA Combined Disk Test. Demographic details of each patient were recorded on a separate questionnaire. Chi-Square goodness-of-fit test was computed to review the isolation of MBL positive isolates (P-value ≤ 0.05) in different specimen. Results: Out of 230 strains of P. aeruginosa 49.5% were imipenem resistant; MBL production was confirmed in 64.9% of the resistant isolates. Resistance to polymyxin B (12.5%) was notable. Majority of the MBL positive strains were isolated from patients aged between 20-39 years (45.9%) and the predominant source was pus (43.24%) which was found to be statistically significant (P-value=0.04). Outpatient departments (24.3%) and burn unit (21.6%) were the major places for resistant isolates. Conclusion: MBL production is one of the major causes of IRPA. Increasing resistance to polymyxin B is grave. Due to acquisition of MBL strains MDR P. aeruginosa has become endemic in tertiary setups. PMID:26150844

Action Dynamics of the Local Supercluster

NASA Astrophysics Data System (ADS)

Shaya, Edward J.; Tully, R. Brent; Hoffman, Yehuda; Pomarède, Daniel

2017-12-01

The fully nonlinear gravitationally induced trajectories of a nearly complete set of galaxies, groups, and clusters in the Local Supercluster are constructed in a numerical action method model constrained by data from the CosmicFlows survey and various distance indicators. We add the gravity field due to inhomogeneities external to the sample sphere by making use of larger-scale peculiar flow measurements. Assignments of total masses were made to find the best overall set of mutual attractions, as determined by a goodness criterion based on present-day radial velocities, individually for the Virgo Cluster, M31, and the Milky Way (MW), and via a mass-to-light ratio relationship for other masses. The low median chi-square found indicates that the model fits the present-day velocity flow well, but a slightly high mean chi-square may indicate that some masses underwent complex orbits. The best fit, when setting the value of H 0 to the CosmicFlows value of 75 km s‑1 Mpc‑1 and the WMAP value for Ω m = 0.244 consistent with that H 0, occurs with the following parameters: Ωorphan = 0.077 ± 0.016, M/{L}K=40+/- 2{L}100.15{M}ȯ /{L}ȯ (L 10 is the K-band luminosity in units of 1010 L ⊙), a Virgo mass of 6.3 ± 0.8 × 1014 M ⊙ (M/L K = 113 ± 15 M ⊙/L ⊙), and a mass for the MW plus M31 of 5.15 ± 0.35 × 1012 M ⊙. The best constant mass-to-light ratio is M/L K = 58 ± 3 M ⊙/L ⊙. The Virgocentric turnaround radius is 7.3 ± 0.3 Mpc. We explain several interesting trends in peculiar motions for various regions now that we can construct the 3D orbital histories.

Tai Chi and Kung-Fu practice maintains physical performance but not vascular health in young versus old participants.

PubMed

McAnulty, Steven; McAnulty, Lisa; Collier, Scott; Souza-Junior, Tacito P; McBride, Jeffrey

2016-01-01

Kung-Fu and Tai Chi along with other martial arts are gaining popularity but studies examining the benefits of martial arts on physical fitness, vascular health, nutrition, and psychological wellness are limited. Aging is associated with declines in these health components. The objectives of this study were to examine whether Tai Chi and Kung-Fu training would maintain physical fitness, vascular health, and psychological wellness components on older versus younger practitioners. Seventeen subjects were recruited and divided into Young (age <40 years, n=9) and Old (age 40 years and above, n=8). Participants reported twice for health screens, vascular and nutrition assessment, and fitness tests. Mean differences were compared between groups for all tests using Student's t-tests. Age, months of practice, systolic blood pressure, and cardiovascular augmentation index were significantly greater in Old versus Young (p=0.001, p=0.007, p=0.049, and p=0.011, respectively). Psychologically, old practitioners experienced greater sleep interference (p=0.035) and overall pain (p=0.036). No other differences existed for any variable. Our study indicates that the practice of Tai Chi and Kung-Fu maintains physical fitness in older compared to younger practitioners. However, age associated changes in cardiovascular stiffness, systolic blood pressure, and pain were not prevented.

The mediating role of psychological empowerment on job satisfaction and organizational commitment for school health nurses: a cross-sectional questionnaire survey.

PubMed

Chang, Li-Chun; Shih, Chia-Hui; Lin, Shu-Man

2010-04-01

The importance of the professional role of school health nurses in promoting children's health in their school environment is widely recognized. However, studies of their working experience have revealed feelings of disempowerment that appear to be related to insufficient support from school managers. In these unsupportive working environments, it seems possible that psychological empowerment may play a mediating role to strengthen employees' satisfaction and commitment to their employing organization. The aim of this study is to test an exploratory model of empowerment in a Taiwanese sample of school health nurses by examining the mediating role of psychological empowerment in the relationship between external factors and work-related attitudes, specifically job satisfaction and organizational commitment. A cross-sectional survey with self-reported questionnaires. Probability proportional sampling was used to generate a randomly selected sample of 500 school health nurses in elementary and junior high schools in Taiwan. A total of 330 valid questionnaires were returned, yielding a response rate of 66%. The exploratory model including all hypothesized variables provided an adequate fit (chi(2)=29.24; df=17; p=.052; adjusted goodness-of-fit index [AGFI]=.96; goodness-of-fit index [GFI]=.98; root-mean-square error of approximation [RMSEA]=.05) for the data and indicated that psychological empowerment did not fully mediate the relationship between organizational empowerment and job satisfaction because of the strong direct effects of organizational empowerment on job satisfaction. The influence of empowerment on organizational commitment was mediated through job satisfaction. Psychological empowerment did not mediate the relationship between external factors and work attitudes, and job satisfaction emerged as an important factor. If school leaders can improve the job satisfaction of school health nurses, this will help them achieve greater commitment and loyalty of school health nurses to their employing schools. Copyright 2009 Elsevier Ltd. All rights reserved.

Distributional Tests for Gravitational Waves from Core-Collapse Supernovae

NASA Astrophysics Data System (ADS)

Szczepanczyk, Marek; LIGO Collaboration

2017-01-01

Core-Collapse Supernovae (CCSN) are spectacular and violent deaths of massive stars. CCSN are some of the most interesting candidates for producing gravitational-waves (GW) transients. Current published results focus on methodologies to detect single GW unmodelled transients. The advantages of these tests are that they do not require a background for which we have an analytical model. Examples of non-parametric tests that will be compared are Kolmogorov-Smirnov, Mann-Whitney, chi squared, and asymmetric chi squared. I will present methodological results using publicly released LIGO-S6 data recolored to the design sensitivity of Advanced LIGO and that will be time lagged between interferometers sites so that the resulting coincident events are not GW.

Gender differences in variance and means on the Naglieri Non-verbal Ability Test: data from the Philippines.

PubMed

Vista, Alvin; Care, Esther

2011-06-01

Research on gender differences in intelligence has focused mostly on samples from Western countries and empirical evidence on gender differences from Southeast Asia is relatively sparse. This article presents results on gender differences in variance and means on a non-verbal intelligence test using a national sample of public school students from the Philippines. More than 2,700 sixth graders from public schools across the country were tested with the Naglieri Non-verbal Ability Test (NNAT). Variance ratios (VRs) and log-transformed VRs were computed. Proportion ratios for each of the ability levels were also calculated and a chi-square goodness-of-fit test was performed. An analysis of variance was performed to determine the overall gender difference in mean scores as well as within each of three age subgroups. Our data show non-existent or trivial gender difference in mean scores. However, the tails of the distributions show differences between the males and females, with greater variability among males in the upper half of the distribution and greater variability among females in the lower half of the distribution. Descriptions of the results and their implications are discussed. Results on mean score differences support the hypothesis that there are no significant gender differences in cognitive ability. The unusual results regarding differences in variance and the male-female proportion in the tails require more complex investigations. ©2010 The British Psychological Society.

FORESEE: Fully Outsourced secuRe gEnome Study basEd on homomorphic Encryption

PubMed Central

2015-01-01

Background The increasing availability of genome data motivates massive research studies in personalized treatment and precision medicine. Public cloud services provide a flexible way to mitigate the storage and computation burden in conducting genome-wide association studies (GWAS). However, data privacy has been widely concerned when sharing the sensitive information in a cloud environment. Methods We presented a novel framework (FORESEE: Fully Outsourced secuRe gEnome Study basEd on homomorphic Encryption) to fully outsource GWAS (i.e., chi-square statistic computation) using homomorphic encryption. The proposed framework enables secure divisions over encrypted data. We introduced two division protocols (i.e., secure errorless division and secure approximation division) with a trade-off between complexity and accuracy in computing chi-square statistics. Results The proposed framework was evaluated for the task of chi-square statistic computation with two case-control datasets from the 2015 iDASH genome privacy protection challenge. Experimental results show that the performance of FORESEE can be significantly improved through algorithmic optimization and parallel computation. Remarkably, the secure approximation division provides significant performance gain, but without missing any significance SNPs in the chi-square association test using the aforementioned datasets. Conclusions Unlike many existing HME based studies, in which final results need to be computed by the data owner due to the lack of the secure division operation, the proposed FORESEE framework support complete outsourcing to the cloud and output the final encrypted chi-square statistics. PMID:26733391

FORESEE: Fully Outsourced secuRe gEnome Study basEd on homomorphic Encryption.

PubMed

Zhang, Yuchen; Dai, Wenrui; Jiang, Xiaoqian; Xiong, Hongkai; Wang, Shuang

2015-01-01

The increasing availability of genome data motivates massive research studies in personalized treatment and precision medicine. Public cloud services provide a flexible way to mitigate the storage and computation burden in conducting genome-wide association studies (GWAS). However, data privacy has been widely concerned when sharing the sensitive information in a cloud environment. We presented a novel framework (FORESEE: Fully Outsourced secuRe gEnome Study basEd on homomorphic Encryption) to fully outsource GWAS (i.e., chi-square statistic computation) using homomorphic encryption. The proposed framework enables secure divisions over encrypted data. We introduced two division protocols (i.e., secure errorless division and secure approximation division) with a trade-off between complexity and accuracy in computing chi-square statistics. The proposed framework was evaluated for the task of chi-square statistic computation with two case-control datasets from the 2015 iDASH genome privacy protection challenge. Experimental results show that the performance of FORESEE can be significantly improved through algorithmic optimization and parallel computation. Remarkably, the secure approximation division provides significant performance gain, but without missing any significance SNPs in the chi-square association test using the aforementioned datasets. Unlike many existing HME based studies, in which final results need to be computed by the data owner due to the lack of the secure division operation, the proposed FORESEE framework support complete outsourcing to the cloud and output the final encrypted chi-square statistics.

Comparative evaluation of a new lactation curve model for pasture-based Holstein-Friesian dairy cows.

PubMed

Adediran, S A; Ratkowsky, D A; Donaghy, D J; Malau-Aduli, A E O

2012-09-01

Fourteen lactation models were fitted to average and individual cow lactation data from pasture-based dairy systems in the Australian states of Victoria and Tasmania. The models included a new "log-quadratic" model, and a major objective was to evaluate and compare the performance of this model with the other models. Nine empirical and 5 mechanistic models were first fitted to average test-day milk yield of Holstein-Friesian dairy cows using the nonlinear procedure in SAS. Two additional semiparametric models were fitted using a linear model in ASReml. To investigate the influence of days to first test-day and the number of test-days, 5 of the best-fitting models were then fitted to individual cow lactation data. Model goodness of fit was evaluated using criteria such as the residual mean square, the distribution of residuals, the correlation between actual and predicted values, and the Wald-Wolfowitz runs test. Goodness of fit was similar in all but one of the models in terms of fitting average lactation but they differed in their ability to predict individual lactations. In particular, the widely used incomplete gamma model most displayed this failing. The new log-quadratic model was robust in fitting average and individual lactations, and was less affected by sampled data and more parsimonious in having only 3 parameters, each of which lends itself to biological interpretation. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Reliability and validity of the Turkish version of the situational self-efficacy scale for fruit and vegetable consumption in adolescents.

PubMed

Kadioglu, Hasibe; Erol, Saime; Ergun, Ayse

2015-01-01

The purpose of this research was to examine the psychometric properties of the Turkish version of the situational self-efficacy scale for vegetable and fruit consumption in adolescents. This was a methodological study. The study was conducted in four public secondary schools in Istanbul, Turkey. Subjects were 1586 adolescents. Content and construct validity were assessed to test the validity of the scale. The reliability was assessed in terms of internal consistency and test-retest reliability. For confirmatory factor analysis, χ(2) statistics plus other fit indices were used, including the goodness-of-fit index, the adjusted goodness-of-fit index, the nonnormed fit index, the comparative fit index, the standardized root mean residual, and the root mean square error of approximation. Pearson's correlation was used for test-retest reliability and item total correlation. The internal consistency was assessed by using Cronbach α. Confirmatory factor analysis strongly supported the three-component structure representing positive social situations (α = .81), negative effect situations (α = .93), and difficult situations (α = .78). Psychometric analyses of the Turkish version of the situational self-efficacy scale indicate high reliability and good content and construct validity. Researchers and health professionals will find it useful to employ the Turkish situational self-efficacy scale in evaluating situational self-efficacy for fruit and vegetable consumption in Turkish adolescents.

Assessment of Caregiver Inventory for Rett Syndrome

PubMed Central

Lane, Jane B.; Salter, Amber R.; Jones, Nancy E.; Cutter, Gary; Horrigan, Joseph; Skinner, Steve A.; Kaufmann, Walter E.; Glaze, Daniel G.; Neul, Jeffrey L.; Percy, Alan K.

2017-01-01

Rett syndrome (RTT) requires total caregiver attention and leads to potential difficulties throughout life. The Caregiver Burden Inventory, designed for Alzheimer disease, was modified to a RTT Caregiver Inventory Assessment (RTT CIA). Reliability and face, construct, and concurrent validity were assessed in caregivers of individuals with RTT. Chi-square or Fisher’s exact test for categorical variables and t-tests or Wilcoxon two-sample tests for continuous variables were utilized. Survey completed by 198 caregivers; 70 caregivers completed follow-up assessment. Exploratory factor analysis revealed good agreement for Physical Burden, Emotional Burden, and Social Burden. Internal reliability was high (Cronbach’s alpha: 0.898). RTT CIA represents a reliable and valid measure, providing a needed metric of caregiver burden in this disorder. PMID:28132121

A threshold method for immunological correlates of protection

PubMed Central

2013-01-01

Background Immunological correlates of protection are biological markers such as disease-specific antibodies which correlate with protection against disease and which are measurable with immunological assays. It is common in vaccine research and in setting immunization policy to rely on threshold values for the correlate where the accepted threshold differentiates between individuals who are considered to be protected against disease and those who are susceptible. Examples where thresholds are used include development of a new generation 13-valent pneumococcal conjugate vaccine which was required in clinical trials to meet accepted thresholds for the older 7-valent vaccine, and public health decision making on vaccination policy based on long-term maintenance of protective thresholds for Hepatitis A, rubella, measles, Japanese encephalitis and others. Despite widespread use of such thresholds in vaccine policy and research, few statistical approaches have been formally developed which specifically incorporate a threshold parameter in order to estimate the value of the protective threshold from data. Methods We propose a 3-parameter statistical model called the a:b model which incorporates parameters for a threshold and constant but different infection probabilities below and above the threshold estimated using profile likelihood or least squares methods. Evaluation of the estimated threshold can be performed by a significance test for the existence of a threshold using a modified likelihood ratio test which follows a chi-squared distribution with 3 degrees of freedom, and confidence intervals for the threshold can be obtained by bootstrapping. The model also permits assessment of relative risk of infection in patients achieving the threshold or not. Goodness-of-fit of the a:b model may be assessed using the Hosmer-Lemeshow approach. The model is applied to 15 datasets from published clinical trials on pertussis, respiratory syncytial virus and varicella. Results Highly significant thresholds with p-values less than 0.01 were found for 13 of the 15 datasets. Considerable variability was seen in the widths of confidence intervals. Relative risks indicated around 70% or better protection in 11 datasets and relevance of the estimated threshold to imply strong protection. Goodness-of-fit was generally acceptable. Conclusions The a:b model offers a formal statistical method of estimation of thresholds differentiating susceptible from protected individuals which has previously depended on putative statements based on visual inspection of data. PMID:23448322

Relation of knowledge and level of education to the rationality of self-medication on childhood diarrhea on the Code River banks in Jogoyudan, Jetis, Yogyakarta

NASA Astrophysics Data System (ADS)

Dania, H.; Ihsan, M. N.

2017-11-01

Self-medication as an alternative is used to reduce the severity of diarrhea. Optimal treatment can be done by increasing the rationalization of self-medication on diarrhea. This can be achieved with good knowledge about self-medication, which is in turn influenced by level of education. The aim of this study was to determine the relationship of knowledge and education level to rationality of self-medication on childhood diarrhea around the Code River in Jogoyudan, Jetis, Yogyakarta. The study was conducted by cross-sectional analytical observational design. The subjects were mothers who had children aged 2-11 years who had experienced diarrhea and had self-medication. Questionnaires were used to assess the rationality of self-medication on children's diarrhea by the parents. The respondents were askeds to fill out about indications, right drugs, doses, time intervals and periods of drug administration. Data were analyzed using chi- square. It was showed that of 40 respondents, 14 respondents (35%) performed rational self-medication on children's diarrhea and 26 respondents (65%). did not rationalize the treatment. The results of a bivariate test obtained a chi-square value of 9.808 (> 3.841) and a p value of 0.002 (<0.05) on the relationship between education level and rationality of self-medication and a chi-square value of 19.476 (> 3.841) and a p value of 0.000 (<0.05) on relationship between knowledge and rationality of self- medication. The conclusion of this study is that there is a correlation between knowledge and level of education and rationality of self-medication on childhood diarrhea on the Code River banks in Jogoyudan, Jetis, Yogyakarta.

How do physicians become medical experts? A test of three competing theories: distinct domains, independent influence and encapsulation models.

PubMed

Violato, Claudio; Gao, Hong; O'Brien, Mary Claire; Grier, David; Shen, E

2018-05-01

The distinction between basic sciences and clinical knowledge which has led to a theoretical debate on how medical expertise is developed has implications for medical school and lifelong medical education. This longitudinal, population based observational study was conducted to test the fit of three theories-knowledge encapsulation, independent influence, distinct domains-of the development of medical expertise employing structural equation modelling. Data were collected from 548 physicians (292 men-53.3%; 256 women-46.7%; mean age = 24.2 years on admission) who had graduated from medical school 2009-2014. They included (1) Admissions data of undergraduate grade point average and Medical College Admission Test sub-test scores, (2) Course performance data from years 1, 2, and 3 of medical school, and (3) Performance on the NBME exams (i.e., Step 1, Step 2 CK, and Step 3). Statistical fit indices (Goodness of Fit Index-GFI; standardized root mean squared residual-SRMR; root mean squared error of approximation-RSMEA) and comparative fit [Formula: see text] of three theories of cognitive development of medical expertise were used to assess model fit. There is support for the knowledge encapsulation three factor model of clinical competency (GFI = 0.973, SRMR = 0.043, RSMEA = 0.063) which had superior fit indices to both the independent influence and distinct domains theories ([Formula: see text] vs [Formula: see text] [[Formula: see text

Parameter Estimation in Astronomy with Poisson-Distributed Data. 1; The (CHI)2(gamma) Statistic

NASA Technical Reports Server (NTRS)

Mighell, Kenneth J.

1999-01-01

Applying the standard weighted mean formula, [Sigma (sub i)n(sub i)ssigma(sub i, sup -2)], to determine the weighted mean of data, n(sub i), drawn from a Poisson distribution, will, on average, underestimate the true mean by approx. 1 for all true mean values larger than approx.3 when the common assumption is made that the error of the i th observation is sigma(sub i) = max square root of n(sub i), 1).This small, but statistically significant offset, explains the long-known observation that chi-square minimization techniques which use the modified Neyman'chi(sub 2) statistic, chi(sup 2, sub N) equivalent Sigma(sub i)((n(sub i) - y(sub i)(exp 2)) / max(n(sub i), 1), to compare Poisson - distributed data with model values, y(sub i), will typically predict a total number of counts that underestimates the true total by about 1 count per bin. Based on my finding that weighted mean of data drawn from a Poisson distribution can be determined using the formula [Sigma(sub i)[n(sub i) + min(n(sub i), 1)](n(sub i) + 1)(exp -1)] / [Sigma(sub i)(n(sub i) + 1)(exp -1))], I propose that a new chi(sub 2) statistic, chi(sup 2, sub gamma) equivalent, should always be used to analyze Poisson- distributed data in preference to the modified Neyman's chi(exp 2) statistic. I demonstrated the power and usefulness of,chi(sub gamma, sup 2) minimization by using two statistical fitting techniques and five chi(exp 2) statistics to analyze simulated X-ray power - low 15 - channel spectra with large and small counts per bin. I show that chi(sub gamma, sup 2) minimization with the Levenberg - Marquardt or Powell's method can produce excellent results (mean slope errors approx. less than 3%) with spectra having as few as 25 total counts.

A Geomagnetic Estimate of Mean Paleointensity

NASA Technical Reports Server (NTRS)

Voorhies, Coerte

2004-01-01

To test a statistical hypothesis about Earth's magnetic field against paleomagnetism, the present field is used to estimate time averaged paleointensity. The estimate uses the modem magnetic multipole spectrum R(n), which gives the mean square induction represented by spherical harmonics of degree n averaged over the sphere of radius a = 6371.2 km. The hypothesis asserts that the low degree multipole powers of the core-source field are distributed as chi-squared with 2n+l degrees of freedom and expectation values {R(n)} = K[(n+l/2)/n(n+l](c/a)(sup 2n+4), where c is the 3480 km radius of Earth's core. (This is compatible with a usually mainly geocentric axial dipolar field). Amplitude K is estimated by fitting theoretical to observational spectra through degree 12. The resulting calibrated expectation spectrum is summed through degree 12 to estimate expected square intensity {F(sup 2)}. The sum also estimates {F(sup 2)} averaged over geologic time, in so far as the present magnetic spectrum is a fair sample of that generated in the past by core geodynamic processes.

The effects of Tai-Chi in conjunction with thera-band resistance exercise on functional fitness and muscle strength among community-based older people.

PubMed

Lin, Shu-Fen; Sung, Huei-Chuan; Li, Tzai-Li; Hsieh, Tsung-Cheng; Lan, Hsiao-Chin; Perng, Shoa-Jen; Smith, Graeme D

2015-05-01

The aim of this study was to investigate the effects of Tai-Chi in conjunction with thera-band resistance exercise on functional fitness and muscle strength in community-based older people. Tai-Chi is known to improve functional fitness in older people. Tai-Chi is usually performed with free hands without resistance training and usually focuses on training lower limbs. To date, no study has examined the use of Tai-Chi in conjunction with thera-band resistance exercise in this population. Cluster randomised trial design. Older people at six senior day care centres in Taiwan were assigned to thera-band resistance exercise or control group using a cluster randomisation. The thera-band resistance exercise group (n = 48) received sixty minute thera-band resistance exercise twice weekly for a period of 16 weeks. The control group (n = 47) underwent routine activities in the day care centre, receiving no Tai-Chi or resistance exercise. After receiving the thera-band resistance exercise, intervention participants displayed a significant increase in muscle strength of upper and lower extremities. Significant improvements were recorded on most measures of the Senior Fitness Test, with the exception of the chair-stand and back-scratch test. Thera-band resistance exercise has the potential to improve functional fitness and muscle strength in community-based older people. Thera-band resistance exercise potentially offers a safe and appropriate form of physical activity that nursing staff can easily incorporate into the daily routine of older people in day care centres, potentially improving functional performance and muscle strength. © 2015 John Wiley & Sons Ltd.

Nutritional supplement use among fitness club participants in Tehran, Iran.

PubMed

Saeedi, Pouya; Mohd Nasir, Mohd Taib; Hazizi, Abu Saad; Vafa, Mohammad Reza; Rahimi Foroushani, Abbas

2013-01-01

The aim of this study was to assess nutritional supplement use among fitness club participants in Tehran, Iran. A cross sectional study was conducted in 24 fitness clubs throughout the city of Tehran, Iran. A total of 1625 fitness club participants were recruited to participate in this study. They were asked to complete a self-administered pre-tested questionnaire. Descriptive statistics and chi-square test were performed to determine the characteristics of participants, reasons for supplement use, sources of information and also the influential advisors regarding nutritional supplement use. A high prevalence rate of nutritional supplement use (66.7%) was reported. Overall, multivitamin-mineral (43.8%) and iron tablets (30.5%) were the common nutritional supplements used and only a small number of participants used illegal substances (0.5%). Younger participants were more likely to use ergogenic aids, whereas, older participants were more likely to use vitamin D. Males were more likely than females to use creatine and amino acids, whereas, iron tablets and mint water were more common among females. Also, males were more likely to use nutritional supplements for increasing energy, whereas, females were more likely to use nutritional supplements for nutritional deficiencies. In conclusion, a high prevalence rate of nutritional supplement use was seen among participants. Copyright © 2012 Elsevier Ltd. All rights reserved.

Validation of "Signs of Inflammation in Children that Kill" (SICK) score for immediate non-invasive assessment of severity of illness.

PubMed

Gupta, Manoj A; Chakrabarty, Anjan; Halstead, Ruth; Sahni, Mohit; Rangasami, Jayanti; Puliyel, Ashish; Sreenivas, Vishnubhatla; Green, David A; Puliyel, Jacob M

2010-04-26

To validate the SICK scoring system's ability to differentiate between individuals with higher and lower probabilities of death We performed a one year two-centre prospective evaluation of all children aged between one month and 12 years referred to the Paediatric team at St Stephens Hospital in Delhi and admitted to the Paediatric Department at West Middlesex University Hospital in London. We calculated SICK scores at presentation and correlated them with subsequent in-hospital mortality. We used discrimination by areas under receiver operating characteristic (ROC) curves to measure performance. We prospectively evaluated 3895 children in Delhi and 1473 children in London. The areas under the ROC curves were 84.8% in Delhi, 81.0% in London and 84.1% (95% CI 77.4-90.8%) for combined data. Hosmer-Lemeshow goodness of fit for the combined data was good (Hosmer-Lemeshow Chi-square=2.13 (p=0.345). We propose the SICK score as a useful triage tool at initial presentation and highlight its particular suitability for resource poor settings.

Validation of "Signs of Inflammation in Children that Kill" (SICK) score for immediate non-invasive assessment of severity of illness

PubMed Central

2010-01-01

Objective To validate the SICK scoring system's ability to differentiate between individuals with higher and lower probabilities of death Method We performed a one year two-centre prospective evaluation of all children aged between one month and 12 years referred to the Paediatric team at St Stephens Hospital in Delhi and admitted to the Paediatric Department at West Middlesex University Hospital in London. We calculated SICK scores at presentation and correlated them with subsequent in-hospital mortality. We used discrimination by areas under receiver operating characteristic (ROC) curves to measure performance. Results We prospectively evaluated 3895 children in Delhi and 1473 children in London. The areas under the ROC curves were 84.8% in Delhi, 81.0% in London and 84.1% (95% CI 77.4 - 90.8%) for combined data. Hosmer-Lemeshow goodness of fit for the combined data was good (Hosmer-Lemeshow Chi-square = 2.13 (p = 0.345). Conclusions We propose the SICK score as a useful triage tool at initial presentation and highlight its particular suitability for resource poor settings. PMID:20420670

Modelling of the batch biosorption system: study on exchange of protons with cell wall-bound mineral ions.

PubMed

Mishra, Vishal

2015-01-01

The interchange of the protons with the cell wall-bound calcium and magnesium ions at the interface of solution/bacterial cell surface in the biosorption system at various concentrations of protons has been studied in the present work. A mathematical model for establishing the correlation between concentration of protons and active sites was developed and optimized. The sporadic limited residence time reactor was used to titrate the calcium and magnesium ions at the individual data point. The accuracy of the proposed mathematical model was estimated using error functions such as nonlinear regression, adjusted nonlinear regression coefficient, the chi-square test, P-test and F-test. The values of the chi-square test (0.042-0.017), P-test (<0.001-0.04), sum of square errors (0.061-0.016), root mean square error (0.01-0.04) and F-test (2.22-19.92) reported in the present research indicated the suitability of the model over a wide range of proton concentrations. The zeta potential of the bacterium surface at various concentrations of protons was observed to validate the denaturation of active sites.

Body image, nutritional status, abdominal strength, and cardiorespiratory fitness in children and adolescents practicing sports.

PubMed

Schubert, Alexandre; Januário, Renata Selvatici B; Casonatto, Juliano; Sonoo, Christi Noriko

2013-01-01

To verify the association between nutritional status, physical fitness, and body image in children and adolescents. This cross-sectional study included 401 students (236 boys and 165 girls) aged between 8 and 16 years that were regularly enrolled in sports in the local clubs. The nutritional status was evaluated by the body mass index. Students were assessed for satisfaction with body image, abdominal strength resistance, and cardiorespiratory fitness. The variables were assessed on the same day following a standardized order. In order to verify relationships between variables, the chi-square test was used. Afterwards, the binary logistic regression was applied to identify the magnitude of the associations, considering p<0.05 as significant. Association was found between body image and body mass index (p=0.001), abdominal strength resistance (p=0.005) and cardiorespiratory fitness (p=0.001). The Odds Ratio for presenting the body image insatisfaction for those who have not achieved the expected values for the health criteria in abdominal strength resistance and cardiorespiratory fitness were 2.14 and 2.42 times respectively, and for those with overweight and obesity, 2.87 times. Insatisfaction with body image is associated with body mass index and also with physical fitness, abdominal strength resistance, and cardiorespiratory fitness variables.

Consistency of Rasch Model Parameter Estimation: A Simulation Study.

ERIC Educational Resources Information Center

van den Wollenberg, Arnold L.; And Others

1988-01-01

The unconditional--simultaneous--maximum likelihood (UML) estimation procedure for the one-parameter logistic model produces biased estimators. The UML method is inconsistent and is not a good alternative to conditional maximum likelihood method, at least with small numbers of items. The minimum Chi-square estimation procedure produces unbiased…

Work related stress and coping mechanisms among bankers in Lagos, Nigeria.

PubMed

Olatona, F A; Ezeobika, E N; Okafor, I P; Owoeye, O B A

2014-03-01

This study assessed knowledge, prevalence, associated factors and mechanisms of coping with stress among bankers in Lagos State. It was a descriptive cross sectional study. A two stage sampling technique was used to select two hundred and twenty seven (227) respondents. Data was collected using a structured self administered questionnaire. The analysis was done using Epi-info version 2002 software and Chi Square was used to determine association between variables at p value 0.05. Fischer's Exact test was used where Chi-square was not valid. The age range of respondents was between 20 and 49 years while the mean age was 31.3 +/- 5.0 years. Only 3.6% had good level of knowledge about stress, 42.2% had fair level while more than half of the respondents had poor level of knowledge about stress (54.3%). Majority (67.0%) of the respondents were moderately stressed while one quarter (24.7%) were highly stressed. Majority (92.4%) of the respondents used good coping mechanisms though 69.5% of the respondents also used bad coping mechanisms. A greater proportion of those who had poor knowledge about stress were stressed or highly stressed (p = 0.002). A statistically significant association was also found between the departments in the bank and level of stress of the respondents (p = 0.002). The prevalence of stress was high among the bank workers studied. It is recommended that effective stress management programmes are implemented to address the problem of stress among bank workers.

Measuring the Processes of Change From the Transtheoretical Model for Physical Activity and Exercise in Overweight and Obese Adults.

PubMed

Romain, Ahmed Jerôme; Bernard, Paquito; Hokayem, Marie; Gernigon, Christophe; Avignon, Antoine

2016-03-01

This study aimed to test three factorial structures conceptualizing the processes of change (POC) from the transtheoretical model and to examine the relationships between the POC and stages of change (SOC) among overweight and obese adults. Cross-sectional study. This study was conducted at the University Hospital of Montpellier, France. A sample of 289 overweight or obese participants (199 women) was enrolled in the study. Participants completed the POC and SOC questionnaires during a 5-day hospitalization for weight management. Structural equation modeling was used to compare the different factorial structures. The unweighted least-squares method was used to identify the best-fit indices for the five fully correlated model (goodness-of-fit statistic = .96; adjusted goodness-of-fit statistic = .95; standardized root mean residual = .062; normed-fit index = .95; parsimonious normed-fit index = .83; parsimonious goodness-of-fit statistic = .78). The multivariate analysis of variance was significant (p < .001). A post hoc test showed that individuals in advanced SOC used more of both experiential and behavioral POC than those in preaction stages, with effect sizes ranging from .06 to .29. This study supports the validity of the factorial structure of POC concerning physical activity and confirms the assumption that, in this context, people with excess weight use both experiential and behavioral processes. These preliminary results should be confirmed in a longitudinal study. © The Author(s) 2016.

Cost Growth in Weapons Systems: Re-examining Rubber Baselines and Economic Factors

DTIC Science & Technology

2007-03-01

committee members for their support in this endeavor. They allowed me to test my econometric limits without performing the analysis for me. I...Bruesch-Pagan Het Test Ramsey Omitted Variable Test 6 The adjusted r-squared value indicates that this model explains nearly 16% of the factors...Observations 1150 Chi2(1) 69.01 P(Chi) 0.0000 F(3, 1139) 7.22 P(F) 0.0001 Bruesch-Pagan Het Test Ramsey Omitted Variable Test The results of these two

Patterns of multi-drug resistant bacteria at first culture from patients admitted to a third level University hospital in Calabria from 2011 to 2014: implications for empirical therapy and infection control.

PubMed

Reale, Mariaconcetta; Strazzulla, Alessio; Quirino, Angela; Rizzo, Claudia; Marano, Vito; Postorino, Maria Concetta; Mazzitelli, Maria; Greco, Giuseppe; Pisani, Vincenzo; Costa, Chiara; Cesana, Bruno Mario; Liberto, Maria Carla; Torti, Carlo; Focà, Alfredo

2017-06-01

Surveillance of antimicrobial drug resistance is fundamental to guide empirical treatment. However, the European Antimicrobial Resistance Surveillance Network provides a general picture, which might not be applicable to clinical settings that are excluded from this survey. We evaluated resistance patterns of ESKAPE isolates over a four-year period in a third level University hospital in the province of Catanzaro (Southern Italy). In this retrospective study, we evaluated the frequency of ESKAPE isolates with different resistance patterns (group 1=low-resistant bacteria; group 2=multi-drug and extremely drug-resistant bacteria; group 3=pan-resistant bacteria), stratified by year (2011, 2012, 2013 and 2014), hospital units (intensive care units, medical and surgical units) and by sample type (urine, blood, wound swabs, respiratory samples, other samples). Chi square test was applied to find differences between isolates with different resistance patterns by hospital unit and by organs and systems. Cochran-Armitage trend test was applied to assess the trend in resistance patterns during the four years analyzed. Amongst 2385 isolates, Escherichia coli (38%) was the most frequent, followed by Pseudomonas aeruginosa (15%), Klebsiella pneumoniae (14%), Staphylococcus aureus (13%), Acinetobacter baumannii (9%), Enterococcus faecalis (8%) and Enterococcus faecium (3%). From 2011 to 2014, frequency of isolates in group 2 plus 3 decreased from 23% to 14% (chi square=55.093; p<0.0001), particularly for E. coli and K. pneumoniae, but the trend increased for S. aureus (from 5% in 2011 to 10% in 2014), and remained stable for the other species. Frequency of isolates in group 2 plus 3 was higher in intensive care units for K. pneumoniae (chi square =32.292; p<0.0001), A. baumannii (chi square =6.947; p<0.0001) and S. aureus (chi square =22.079; p<0.0001). It was also higher from blood than from different sources for most species.

A population-based randomized controlled trial of the effect of combining a pedometer with an intervention toolkit on physical activity among individuals with low levels of physical activity or fitness.

PubMed

Petersen, Christina Bjørk; Severin, Maria; Hansen, Andreas Wolff; Curtis, Tine; Grønbæk, Morten; Tolstrup, Janne Schurmann

2012-02-01

To examine if receiving a pedometer along with an intervention toolkit is associated with increased physical activity, aerobic fitness and better self-rated health among individuals with low levels of physical activity or fitness. The intervention was nested in the Danish Health Examination Survey (DANHES) and carried out in 2008. Participants were randomly assigned to either a pedometer group (n=326) or a control group (n=329). Physical activity, aerobic fitness, and self-rated health were measured at baseline and at 3-month follow-up, and differences were tested by Wilcoxons signed rank tests and Chi-squared tests. At follow-up, no significant differences in physical activity, aerobic fitness and self-rated health were found between the groups. However, the oldest participants in the pedometer group reported significantly more walking time compared to the controls (controls=368 min/week, pedometer group=680 min/week, P=0.05). Among participants who completed the intervention, a significant effect on total walking time was observed (median difference=225 min/week, P=0.04). The results suggest that receiving a pedometer and along with an intervention toolkit can increase walking time in older individuals, but not in younger individuals. Thus, this type of intervention offers great potential for promoting physical activity in older individuals. NCT01071811. Copyright © 2011 Elsevier Inc. All rights reserved.

Surveying the factor structure and reliability of the Persian version of the Jefferson Scale of Physician Lifelong Learning (JeffSPLL) in staff of medical sciences.

PubMed

Karimi, Fatemeh Zahra; Alesheikh, Aytay; Pakravan, Soheila; Abdollahi, Mahbubeh; Damough, Mozhdeh; Anbaran, Zahra Khosravi; Farahani, Leila Amiri

2017-10-01

In medical sciences, commitment to lifelong learning has been expressed as an important element. Today, due to the rapid development of medical information and technology, lifelong learning is critical for safe medical care and development in medical research. JeffSPLL is one of the scales for measuring lifelong learning among the staff of medical sciences that has never been used in Iran. The aim of the present study was to determine the factor structure and reliability of the Persian version of JeffSPLL among Persian-speaking staff of universities of medical sciences in Iran. This study was a cross-sectional study, methodologically, that was conducted in 2012-2013. In this study, 210 staff members of Birjand University of Medical Sciences were selected. Data collection tool was the Persian version of JeffSPLL. To investigate the factor structure of this tool, confirmatory factor analysis was used and to evaluate the model fit, goodness-of-fit indices, root mean square error of approximation (RMSEA), the ratio of chi-square to the degree of freedom associated with it, comparative fit index (CFI), and root mean square residual (RMR) were used. To investigate the reliability of tool, Cronbach's alpha was employed. Data analysis was conducted using LISREL8.8 and SPSS 20 software. Confirmatory factor analysis showed that RMSEA was close to 0.1, and CFI and GFI were close to one. Therefore, four-factor model was appropriate. Cronbach's alpha was 0.92 for the whole tool and it was between 0.82 and 0.89 for subscales. The present study verified the four-factor structure of the 19-item Persian version of JeffSPLL that included professional learning beliefs and motivation, scholarly activities, attention to learning opportunities, and technical skills in information seeking among the staff. In addition, this tool has acceptable reliability. Therefore, it was appropriate to assess lifelong learning in the Persian-speaking staff population.

Herd-level risk factors for bovine viral diarrhea infection in cattle of Tamil Nadu.

PubMed

Kumar, Subbiah Krishna; Palanivel, K M; Sukumar, K; Ronald, B Samuel Masilamoni; Selvaraju, G; Ponnudurai, G

2018-04-01

A cross-sectional study was carried out to identify risk factors for bovine viral diarrhea virus (BVDV) infection in 62 randomly selected dairy herds which were tested for BVD serum antibodies by using an indirect ELISA kit (IDEXX). Results from the chi-square test analysis were interpreted by analyzing by chi-square test. A sum of 500 sera samples were screened and 66 animals (13.20%) showed positive for BVDV antibody. Within herd, BVD seroprevalence was 12-65%. This study concluded that epidemiological risk factors like location, herd size, housing patterns like, tail to tail system, roofing pattern, distance between the manure pit and farm, and distance between farms were significantly associated with BVDV serological status (P < 0.05).

Implications of New Methane Absorption Coefficients on Uranus Vertical Structure Derived from Near-IR Spectra

NASA Astrophysics Data System (ADS)

Fry, Patrick M.; Sromovsky, L. A.

2009-09-01

Using new methane absorption coefficients from Karkoschka and Tomasko (2009, submitted to Icarus, "Methane Absorption Coefficients for the Jovian Planets from Laboratory, Huygens, and HST Data"), we fit Uranus near-IR spectra previously analyzed in Sromovsky et al. (2006, Icarus 182, 577-593, Fink and Larson, 1979 J- and H-band), Sromovsky and Fry (2008, Icarus 193, 252-266, 2006 NIRC2 J- and H-band, 2006 SpeX) using Irwin et al. (2006, Icarus 181, 309-319) methane absorption coefficients. Because the new absorption coefficients usually result in higher opacities at the low temperatures seen in Uranus' upper troposphere, our previously derived cloud altitudes are expected to generally rise to higher altitudes. For example, using Lindal et al. (1987, JGR 92, 14987-15001) model D temperature and methane abundance profiles, we are better able to fit the J-band 43-deg. south bright band with the new coefficients (chi-square=205, vs. 315 for Irwin), with the pressure of the upper tropospheric cloud decreasing to 1.6 bars (from 2.4 bars using Irwin coefficients). Improvements in fitting H-band spectra from the same latitude are not as readily obtained. Derived upper tropospheric cloud pressures are very similar using the two absorption datasets (1.6-1.7 bars), but the character of the fits differs. New Karkoschka and Tomasko coefficients better fit some details in the 1.5-1.58 micron region, but Irwin fits the broad absorption band wing at 1.61-1.62 microns better, and the fit chi-square values are similar (K&T: 243, Irwin: 220). Results for a higher methane concentration (Lindal et al. model F) were similar. Whether the new coefficients will simply raise derived altitudes across the planet or will result in fundamental changes in structure is as yet unclear. This work was suported by NASA planetary astronomy and planetary atmospheres programs.

2 × 2 Tables: a note on Campbell's recommendation.

PubMed

Busing, F M T A; Weaver, B; Dubois, S

2016-04-15

For 2 × 2 tables, Egon Pearson's N - 1 chi-squared statistic is theoretically more sound than Karl Pearson's chi-squared statistic, and provides more accurate p values. Moreover, Egon Pearson's N - 1 chi-squared statistic is equal to the Mantel-Haenszel chi-squared statistic for a single 2 × 2 table, and as such, is often available in statistical software packages like SPSS, SAS, Stata, or R, which facilitates compliance with Ian Campbell's recommendations. Copyright © 2015 John Wiley & Sons, Ltd.

Generating Fiducial Cuts for CLAS E5

NASA Astrophysics Data System (ADS)

Greenholt, Kristen

2005-04-01

The Thomas Jefferson National Accelerator Facility, located in Newport News, Virginia, is home to CLAS (CEBAF Large Acceptance Spectrometer) which observes the scattering effects of high-energy collisions of an electron beam and a proton or deuteron target. When data are collected with CLAS, one of the properties measured is the cross-section, which is proportional to the number of events and the efficiency and inversely proportional to the solid angle. The efficiency, or acceptance of the detector, is the ratio between the data one expects to observe in an ideal detector and the data that we actually measure with the real CLAS detector. In outlying azimuthal regions, the efficiency is less clearly understood, which leads to measurements which are reliant on the conditions of the detector itself. In order to analyze data which fall in regions of stable and well-understood efficiency, we generated fiducial cuts on CLAS. Our fiducial cuts fit a function to the edges of regions of stable efficiency. These cuts enable us to focus on the data with good acceptance/efficiency. When examining at the fiducial cuts, we required stable efficiency, or flat regions, a good visual fit, a minimized chi squared, and a reasonable behavior in each in azimuthal versus polar angle plane for each electron-momentum bin. Generating these fiducial cuts enables us to focus on data from CLAS where the efficiency of the detector is well understood.

Fit between Africa and Antarctica: A Continental Drift Reconstruction.

PubMed

Dietz, R S; Sproll, W P

1970-03-20

A computerized (smallest average misfit) best fit position is obtained for the juxtaposition of Africa and Antarctica in a continental drift reconstruction. An S-shaped portion of the Weddell and Princess Martha Coast regions of western East Antarctica is fitted into a similar profile along southeastern Africa. The total amount of overlap is 36,300 square kilometers, and the underlap is 23,600 square kilometers; the total mismatch is thus of 59,900 square kilometers. The congruency along the 1000-fathom isobath is remarkably good and suggests that this reconstruction is valid within the overall framework of the Gondwana supercontinent.

Comparison of delinquents and nondelinquents in ethnicity, ordinal position, and self-perception.

PubMed

Calhoun, G; Connley, S; Bolton, J A

1984-01-01

Compared three groups of black, white, and Mexican-American delinquent and nondelinquent males, aged 11 to 18, on measures of self-concept, self-esteem, and ordinal position by groups (N = 135). Data were analyzed with analysis of variance and Chi-square test. Significant main effects were found with respect to delinquency, self-concept, and self-esteem. A significant interaction was present for delinquency and ethnicity for both self-concept and self-esteem. Chi-square results found birth-order and ethnicity to be related significantly.

Evaluating the MSCEIT V2.0 via CFA: comment on Mayer et al. (2003).

PubMed

Gignac, Gilles E

2005-06-01

This investigation uncovered several substantial errors in the confirmatory factor analysis results reported by J. D. Mayer, P. Salovey, D. R. Caruso, and G. Sitarenios (see record 2003-02341-015). Specifically, the values associated with the close-fit indices (normed fit index, Tucker-Lewis Index, and root-mean-square error of approximation) are inaccurate. A reanalysis of the Mayer et al. subscale intercorrelation matrix provided accurate values of the close-fit indices, which resulted in different evaluations of the models tested by J. D. Mayer et al. Contrary to J. D. Mayer et al., the 1-factor model and the 2-factor model did not provide good fit. Although the 4-factor model was still considered good fitting, the non-constrained 4-factor model yielded a non-positive definite matrix, which was interpreted to be due to the fact that two of the branch-level factors (Perceiving and Facilitating) were collinear, suggesting that a model with 4 factors was implausible.

Empirical likelihood-based confidence intervals for the sensitivity of a continuous-scale diagnostic test at a fixed level of specificity.

PubMed

Gengsheng Qin; Davis, Angela E; Jing, Bing-Yi

2011-06-01

For a continuous-scale diagnostic test, it is often of interest to find the range of the sensitivity of the test at the cut-off that yields a desired specificity. In this article, we first define a profile empirical likelihood ratio for the sensitivity of a continuous-scale diagnostic test and show that its limiting distribution is a scaled chi-square distribution. We then propose two new empirical likelihood-based confidence intervals for the sensitivity of the test at a fixed level of specificity by using the scaled chi-square distribution. Simulation studies are conducted to compare the finite sample performance of the newly proposed intervals with the existing intervals for the sensitivity in terms of coverage probability. A real example is used to illustrate the application of the recommended methods.

Does positivity mediate the relation of extraversion and neuroticism with subjective happiness?

PubMed

Lauriola, Marco; Iani, Luca

2015-01-01

Recent theories suggest an important role of neuroticism, extraversion, attitudes, and global positive orientations as predictors of subjective happiness. We examined whether positivity mediates the hypothesized relations in a community sample of 504 adults between the ages of 20 and 60 years old (females = 50%). A model with significant paths from neuroticism to subjective happiness, from extraversion and neuroticism to positivity, and from positivity to subjective happiness fitted the data (Satorra-Bentler scaled chi-square (38) = 105.91; Comparative Fit Index = .96; Non-Normed Fit Index = .95; Root Mean Square Error of Approximation = .060; 90% confidence interval = .046, .073). The percentage of subjective happiness variance accounted for by personality traits was only about 48%, whereas adding positivity as a mediating factor increased the explained amount of subjective happiness to 78%. The mediation model was invariant by age and gender. The results show that the effect of extraversion on happiness was fully mediated by positivity, whereas the effect of neuroticism was only partially mediated. Implications for happiness studies are also discussed.

VizieR Online Data Catalog: Transiting planet WASP-50b (Tregloan-Reed+, 2013)

NASA Astrophysics Data System (ADS)

Tregloan-Reed, J.; Southworth, J.

2018-05-01

Two high-quality light curves of transits of the extrasolar planetary system WASP-50 are presented. They were obtained using the 3.6m NTT at ESO La Silla, Chile, in the Gunn r passband. The errorbars for each transit have been scaled so the best-fitting model (obtained using the JKTEBOP code) has a reduced chi-squared value of 1.0. (1 data file).

V3885 Sagittarius: A Comparison With a Range of Standard Model Accretion Disks

NASA Technical Reports Server (NTRS)

Linnell, Albert P.; Godon, Patrick; Hubeny, Ivan; Sion, Edward M; Szkody, Paula; Barrett, Paul E.

2009-01-01

A chi-squared analysis of standard model accretion disk synthetic spectrum fits to combined Far Ultraviolet Spectroscopic Explorer and Space Telescope Imaging Spectrograph spectra of V3885 Sagittarius, on an absolute flux basis, selects a model that accurately represents the observed spectral energy distribution. Calculation of the synthetic spectrum requires the following system parameters. The cataclysmic variable secondary star period-mass relation calibrated by Knigge in 2006 and 2007 sets the secondary component mass. A mean white dwarf (WD) mass from the same study, which is consistent with an observationally determined mass ratio, sets the adopted WD mass of 0.7M(solar mass), and the WD radius follows from standard theoretical models. The adopted inclination, i = 65 deg, is a literature consensus, and is subsequently supported by chi-squared analysis. The mass transfer rate is the remaining parameter to set the accretion disk T(sub eff) profile, and the Hipparcos parallax constrains that parameter to mas transfer = (5.0 +/- 2.0) x 10(exp -9) M(solar mass)/yr by a comparison with observed spectra. The fit to the observed spectra adopts the contribution of a 57,000 +/- 5000 K WD. The model thus provides realistic constraints on mass transfer and T(sub eff) for a large mass transfer system above the period gap.

A clinical study of patient acceptance and satisfaction of Varilux Plus and Varilux Infinity lenses.

PubMed

Cho, M H; Barnette, C B; Aiken, B; Shipp, M

1991-06-01

An independent study was conducted at the UAB School of Optometry to determine the clinical success with Varilux Plus (Varilux 2) and Varilux Infinity progressive addition lenses (PAL). Two hundred eighty patients (280) were fit between June 1988 and May 1989. The acceptance rate of 97.5 percent was based on the number of lenses ordered versus the number of lenses returned. Patients were contacted by telephone and asked to rate their level of satisfaction with their PALs. A chi-square (non-parametric) test revealed no statistically significant differences in levels of satisfaction with respect to gender, PAL type, or degree of presbyopia. Also, neither refractive error nor previous lens history had a measurable impact on patient satisfaction.

Measuring Microaggression and Organizational Climate Factors in Military Units

DTIC Science & Technology

2011-04-01

i.e., items) to accurately assess what we intend for them to measure. To assess construct and convergent validity, the author assessed the statistical ...sample indicated both convergent and construct validity of the microaggression scale. Table 5 presents these statistics . Measuring Microaggressions...models. As shown in Table 7, the measurement models had acceptable fit indices. That is, the Chi-square statistics were at their minimum; although the

Syndromes of collateral-reported psychopathology for ages 18-59 in 18 Societies

PubMed Central

Ivanova, Masha Y.; Achenbach, Thomas M.; Rescorla, Leslie A.; Turner, Lori V.; Árnadóttir, Hervör Alma; Au, Alma; Caldas, J. Carlos; Chaalal, Nebia; Chen, Yi Chuen; da Rocha, Marina M.; Decoster, Jeroen; Fontaine, Johnny R.J.; Funabiki, Yasuko; Guðmundsson, Halldór S.; Kim, Young Ah; Leung, Patrick; Liu, Jianghong; Malykh, Sergey; Marković, Jasminka; Oh, Kyung Ja; Petot, Jean-Michel; Samaniego, Virginia C.; Silvares, Edwiges Ferreira de Mattos; Šimulionienė, Roma; Šobot, Valentina; Sokoli, Elvisa; Sun, Guiju; Talcott, Joel B.; Vázquez, Natalia; Zasępa, Ewa

2017-01-01

The purpose was to advance research and clinical methodology for assessing psychopathology by testing the international generalizability of an 8-syndrome model derived from collateral ratings of adult behavioral, emotional, social, and thought problems. Collateral informants rated 8,582 18–59-year-old residents of 18 societies on the Adult Behavior Checklist (ABCL). Confirmatory factor analyses tested the fit of the 8-syndrome model to ratings from each society. The primary model fit index (Root Mean Square Error of Approximation) showed good model fit for all societies, while secondary indices (Tucker Lewis Index, Comparative Fit Index) showed acceptable to good fit for 17 societies. Factor loadings were robust across societies and items. Of the 5,007 estimated parameters, 4 (0.08%) were outside the admissible parameter space, but 95% confidence intervals included the admissible space, indicating that the 4 deviant parameters could be due to sampling fluctuations. The findings are consistent with previous evidence for the generalizability of the 8-syndrome model in self-ratings from 29 societies, and support the 8-syndrome model for operationalizing phenotypes of adult psychopathology from multi-informant ratings in diverse societies. PMID:29399019

Coalesced chitosan activated carbon composite for batch and fixed-bed adsorption of cationic and anionic dyes.

PubMed

Auta, M; Hameed, B H

2013-05-01

A renewable waste tea activated carbon (WTAC) was coalesced with chitosan to form composite adsorbent used for waste water treatment. Adsorptive capacities of crosslinked chitosan beads (CCB) and its composite (WTAC-CCB) for Methylene blue dye (MB) and Acid blue 29 (AB29) were evaluated through batch and fixed-bed studies. Langmuir, Freundlich and Temkin adsorption isotherms were tested for the adsorption process and the experimental data were best fitted by Langmuir model and least by Freundlich model; the suitability of fitness was adjudged by the Chi-square (χ(2)) and Marquadt's percent standard deviation error functions. Judging by the values of χ(2), pseudo-second-order reaction model best described the adsorption process than pseudo-first-order kinetic model for MB/AB29 on both adsorbents. After five cycles of adsorbents desorption test, more than 50% WTAC-CCB adsorption efficiency was retained while CCB had <20% adsorption efficiency. The results of this study revealed that WTAC-CCB composite is a promising adsorbent for treatment of anionic and cationic dyes in effluent wastewaters. Copyright © 2012 Elsevier B.V. All rights reserved.

Mixture distributions of wind speed in the UAE

NASA Astrophysics Data System (ADS)

Shin, J.; Ouarda, T.; Lee, T. S.

2013-12-01

Wind speed probability distribution is commonly used to estimate potential wind energy. The 2-parameter Weibull distribution has been most widely used to characterize the distribution of wind speed. However, it is unable to properly model wind speed regimes when wind speed distribution presents bimodal and kurtotic shapes. Several studies have concluded that the Weibull distribution should not be used for frequency analysis of wind speed without investigation of wind speed distribution. Due to these mixture distributional characteristics of wind speed data, the application of mixture distributions should be further investigated in the frequency analysis of wind speed. A number of studies have investigated the potential wind energy in different parts of the Arabian Peninsula. Mixture distributional characteristics of wind speed were detected from some of these studies. Nevertheless, mixture distributions have not been employed for wind speed modeling in the Arabian Peninsula. In order to improve our understanding of wind energy potential in Arabian Peninsula, mixture distributions should be tested for the frequency analysis of wind speed. The aim of the current study is to assess the suitability of mixture distributions for the frequency analysis of wind speed in the UAE. Hourly mean wind speed data at 10-m height from 7 stations were used in the current study. The Weibull and Kappa distributions were employed as representatives of the conventional non-mixture distributions. 10 mixture distributions are used and constructed by mixing four probability distributions such as Normal, Gamma, Weibull and Extreme value type-one (EV-1) distributions. Three parameter estimation methods such as Expectation Maximization algorithm, Least Squares method and Meta-Heuristic Maximum Likelihood (MHML) method were employed to estimate the parameters of the mixture distributions. In order to compare the goodness-of-fit of tested distributions and parameter estimation methods for sample wind data, the adjusted coefficient of determination, Bayesian Information Criterion (BIC) and Chi-squared statistics were computed. Results indicate that MHML presents the best performance of parameter estimation for the used mixture distributions. In most of the employed 7 stations, mixture distributions give the best fit. When the wind speed regime shows mixture distributional characteristics, most of these regimes present the kurtotic statistical characteristic. Particularly, applications of mixture distributions for these stations show a significant improvement in explaining the whole wind speed regime. In addition, the Weibull-Weibull mixture distribution presents the best fit for the wind speed data in the UAE.

In Defense of the Chi-Square Continuity Correction.

ERIC Educational Resources Information Center

Veldman, Donald J.; McNemar, Quinn

Published studies of the sampling distribution of chi-square with and without Yates' correction for continuity have been interpreted as discrediting the correction. Yates' correction actually produces a biased chi-square value which in turn yields a better estimate of the exact probability of the discrete event concerned when used in conjunction…

Nursing professional practice environments: setting the stage for constructive conflict resolution and work effectiveness.

PubMed

Siu, Heidi; Spence Laschinger, Heather K; Finegan, Joan

2008-05-01

The aim of this study was to examine the impact of nurses' perceived professional practice environment on their quality of nursing conflict management approaches and ultimately their perceptions of unit effectiveness from the perspective of Deutsch's theory of constructive conflict management. Rising reports of hostility and conflict among Canadian nurses are a concern to nurses' health and the viability of effective patient care delivery. However, research on the situational factors that influence nurses' ability to apply effective conflict resolution skills that lead to positive results in practice is limited. A nonexperimental, predictive design was used in a sample of 678 registered nurses working in community hospitals within a large metropolitan area in Ontario. The results supported a modified version of the hypothesized model [chi2(1) = 16.25, Goodness of Fit = 0.99, Comparative Fit Index = 0.98, Root-Mean-Square Error of Approximation = 0.15] linking professional practice environment and core self-evaluation to nurses' conflict management and, ultimately, unit effectiveness. Professional practice environment, conflict management, and core-self evaluation explained approximately 46.6% of the variance in unit effectiveness. Positive professional practice environments and high core self-evaluations predicted nurses' constructive conflict management and, in turn, greater unit effectiveness.

Perceptions of acceptable conducts by university students.

PubMed

Marques, Dora Nazaré; Macedo, António Filipe

2016-01-01

To determine perceptions of acceptable conducts amongst under and postgraduate optometry students and to compare them with students from other disciplines. Students (under/postgraduate) of optometry (n=156) and other courses (n=54) from University of Minho participated in a voluntary online questionnaire about perception of conducts, classifying as acceptable or unacceptable 15 academic or professional scenarios. 210 questionnaires were analyzed. Differences in perceptions were found between optometry under and postgraduates in scenario 5, Chi-square(2,156)=4.3, p=0.038, and scenario 7, Chi-square(2,156)=7.0, p=0.008 (both with cheating more acceptable for postgrads). Differences between under and postgraduates from other courses were found in scenario 9 (taking supplies from classroom more acceptable for undergrads), Chi-square(1,54)=5.0, p=0.025, and scenario 14 (forging a signature more acceptable for postgrads), Chi-square(1,54)=3.9, p=0.046. Differences between optometry and other courses undergraduates were observed in scenario 2 (plagiarism more acceptable for optometry undergrads), Chi-square(1,154)=8.3, p=0.004 and scenario 9 (taking supplies from classroom more acceptable for other undergrads), chi-square(1,54)=7.8, p=0.005. Differences between optometry and other courses postgraduates were observed in scenario 7, Chi-square(1,56)=5.8, p=0.016, scenario 10 (both with cheating more acceptable for optometry postgrads), chi-square(1,54)=8.1, p=0.004 and scenario 14 (forging a signature more acceptable for other postgrads), Chi-square(1,54)=6.1, p=0.026. Academic misconducts were mainly considered more acceptable than professional misconducts. Our results show that perceptions of acceptable conducts amongst optometry students are not very different from other students, and, against our initial prediction, do not show a general change in misconduct perception when students become more mature. Universities should pay more attention to this problem and take action. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

Affected sib pair tests in inbred populations.

PubMed

Liu, W; Weir, B S

2004-11-01

The affected-sib-pair (ASP) method for detecting linkage between a disease locus and marker loci was first established 50 years ago, and since then numerous modifications have been made. We modify two identity-by-state (IBS) test statistics of Lange (Lange, 1986a, 1986b) to allow for inbreeding in the population. We evaluate the power and false positive rates of the modified tests under three disease models, using simulated data. Before estimating false positive rates, we demonstrate that IBS tests are tests of both linkage and linkage disequilibrium between marker and disease loci. Therefore, the null hypothesis of IBS tests should be no linkage and no LD. When the population inbreeding coefficient is large, the false positive rates of Lange's tests become much larger than the nominal value, while those of our modified tests remain close to the nominal value. To estimate power with a controlled false positive rate, we choose the cutoff values based on simulated datasets under the null hypothesis, so that both Lange's tests and the modified tests generate same false positive rate. The powers of Lange's z-test and our modified z-test are very close and do not change much with increasing inbreeding. The power of the modified chi-square test also stays stable when the inbreeding coefficient increases. However, the power of Lange's chi-square test increases with increasing inbreeding, and is larger than that of our modified chi-square test for large inbreeding coefficients. The power is high under a recessive disease model for both Lange's tests and the modified tests, though the power is low for additive and dominant disease models. Allowing for inbreeding is therefore appropriate, at least for diseases known to be recessive.

Is there an association between astrological data and personality?

PubMed

Hume, N

1977-07-01

A test was made of the hypothesis that personality characteristics can be predicted on the basis of various features of the individual's astrological chart. Astrological charts were prepared for 196 college-age Ss who also were administered the MMPI and the Leary Interpersonal Check List. Ss were divided into those who had extreme scores on any of the 13 personality variables studied and those who did not. For each personality variable, comparisons were made on a large number of astrological dimensions between distributions of Ss with and without extreme test scores. Six hundred thirty-two such comparisons were made and evaluated with chi-square tests. In that the obtained number of statistically significnat chi-squares was less than what would be expected on a chance basis, the hypothesis was rejected.

An early, novel illness severity score to predict outcome after cardiac arrest.

PubMed

Rittenberger, Jon C; Tisherman, Samuel A; Holm, Margo B; Guyette, Francis X; Callaway, Clifton W

2011-11-01

Illness severity scores are commonly employed in critically ill patients to predict outcome. To date, prior scores for post-cardiac arrest patients rely on some event-related data. We developed an early, novel post-arrest illness severity score to predict survival, good outcome and development of multiple organ failure (MOF) after cardiac arrest. Retrospective review of data from adults treated after in-hospital or out-of-hospital cardiac arrest in a single tertiary care facility between 1/1/2005 and 12/31/2009. In addition to clinical data, initial illness severity was measured using serial organ function assessment (SOFA) scores and full outline of unresponsiveness (FOUR) scores at hospital or intensive care unit arrival. Outcomes were hospital mortality, good outcome (discharge to home or rehabilitation) and development of multiple organ failure (MOF). Single-variable logistic regression followed by Chi-squared automatic interaction detector (CHAID) was used to determine predictors of outcome. Stepwise multivariate logistic regression was used to determine the independent association between predictors and each outcome. The Hosmer-Lemeshow test was used to evaluate goodness of fit. The n-fold method was used to cross-validate each CHAID analysis and the difference between the misclassification risk estimates was used to determine model fit. Complete data from 457/495 (92%) subjects identified distinct categories of illness severity using combined FOUR motor and brainstem subscales, and combined SOFA cardiovascular and respiratory subscales: I. Awake; II. Moderate coma without cardiorespiratory failure; III. Moderate coma with cardiorespiratory failure; and IV. Severe coma. Survival was independently associated with category (I: OR 58.65; 95% CI 27.78, 123.82; II: OR 14.60; 95% CI 7.34, 29.02; III: OR 10.58; 95% CI 4.86, 23.00). Category was also similarly associated with good outcome and development of MOF. The proportion of subjects in each category changed over time. Initial illness severity explains much of the variation in cardiac arrest outcome. This model provides prognostic information at hospital arrival and may be used to stratify patients in future studies. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Adaptive channel estimation for soft decision decoding over non-Gaussian optical channel

NASA Astrophysics Data System (ADS)

Xiang, Jing-song; Miao, Tao-tao; Huang, Sheng; Liu, Huan-lin

2016-10-01

An adaptive priori likelihood ratio (LLR) estimation method is proposed over non-Gaussian channel in the intensity modulation/direct detection (IM/DD) optical communication systems. Using the nonparametric histogram and the weighted least square linear fitting in the tail regions, the LLR is estimated and used for the soft decision decoding of the low-density parity-check (LDPC) codes. This method can adapt well to the three main kinds of intensity modulation/direct detection (IM/DD) optical channel, i.e., the chi-square channel, the Webb-Gaussian channel and the additive white Gaussian noise (AWGN) channel. The performance penalty of channel estimation is neglected.

Multivariate normality

NASA Technical Reports Server (NTRS)

Crutcher, H. L.; Falls, L. W.

1976-01-01

Sets of experimentally determined or routinely observed data provide information about the past, present and, hopefully, future sets of similarly produced data. An infinite set of statistical models exists which may be used to describe the data sets. The normal distribution is one model. If it serves at all, it serves well. If a data set, or a transformation of the set, representative of a larger population can be described by the normal distribution, then valid statistical inferences can be drawn. There are several tests which may be applied to a data set to determine whether the univariate normal model adequately describes the set. The chi-square test based on Pearson's work in the late nineteenth and early twentieth centuries is often used. Like all tests, it has some weaknesses which are discussed in elementary texts. Extension of the chi-square test to the multivariate normal model is provided. Tables and graphs permit easier application of the test in the higher dimensions. Several examples, using recorded data, illustrate the procedures. Tests of maximum absolute differences, mean sum of squares of residuals, runs and changes of sign are included in these tests. Dimensions one through five with selected sample sizes 11 to 101 are used to illustrate the statistical tests developed.

Generalizing Terwilliger's likelihood approach: a new score statistic to test for genetic association.

PubMed

el Galta, Rachid; Uitte de Willige, Shirley; de Visser, Marieke C H; Helmer, Quinta; Hsu, Li; Houwing-Duistermaat, Jeanine J

2007-09-24

In this paper, we propose a one degree of freedom test for association between a candidate gene and a binary trait. This method is a generalization of Terwilliger's likelihood ratio statistic and is especially powerful for the situation of one associated haplotype. As an alternative to the likelihood ratio statistic, we derive a score statistic, which has a tractable expression. For haplotype analysis, we assume that phase is known. By means of a simulation study, we compare the performance of the score statistic to Pearson's chi-square statistic and the likelihood ratio statistic proposed by Terwilliger. We illustrate the method on three candidate genes studied in the Leiden Thrombophilia Study. We conclude that the statistic follows a chi square distribution under the null hypothesis and that the score statistic is more powerful than Terwilliger's likelihood ratio statistic when the associated haplotype has frequency between 0.1 and 0.4 and has a small impact on the studied disorder. With regard to Pearson's chi-square statistic, the score statistic has more power when the associated haplotype has frequency above 0.2 and the number of variants is above five.

[Modification and evaluation of assessment of 
medication literacy].

PubMed

Zheng, Feng; Zhong, Zhuqing; Ding, Siqing; Luo, Aijing; Liu, Zina

2016-11-28

To translate and revise the Medication Literacy Assessment in English (MedLitRxSE-English) and evaluate its validity and reliability.
 Methods: We introduced MedLitRxSE-English from abroad. According to the principles of Brislin and culture adjustment, we revised it as a Chinese edition. Using random sampling method, from Oct, 2014 to Jan, 2015, 461 non-hospitalized patients from the outpatient departments of the top three hospitals in Changsha city were investigated. The reliability and validity of the scale was tested.
 Results: The test-retest reliability of the Chinese version for medication literacy scale was 0.885; the split reliability was 0.840; K-R was 0.820; the correlations between the assessment of medication literacy and the corresponding items were 0.427-0.587; the confirmatory factor analysis revealed overall good fit. Root mean square error of approximation (RMSEA), χ2/df, goodness of fit index (GFI) and comparative fit index (CFI) was 0.08, 3.06, 0.91 and 0.94, respectively. 
 Conclusion: The Chinese version for the assessment of medication literacy is in good reliability and validity, and it can be used to evaluate the medication literacy in our country.

Customers' satisfaction about prehospital emergency medical services in Lorestan, Iran.

PubMed

Heydari, Heshmatolah; Kamran, Aziz; Zali, Morad Esmaiel; Novinmehr, Nasser; Safari, Mehdi

2017-03-01

Patient's satisfaction with health care in ambulance services is an important quality indicator and a helpful tool for managers of prehospital emergency services. This study aimed to measure patient satisfaction with health provided by prehospital emergency medical services (EMS) in Lorestan, Iran. This cross-sectional study was conducted on patients (n=450) transferred by EMS to hospitals of Lorestan University of Medical Sciences in a two-year period (2013-2014). Data collection was performed by patient questionnaire, which is a standard LKFR tool. Validity and reliability of the instrument was confirmed by scientific method. Collected data were analyzed by SPSS Version 19. Descriptive and inferential statistics such as Chi-square, paired-samples t-test, independent-samples t-test, ANOVA, Pearson's product-moment correlation coefficient, and Fisher's exact test were used. One hundred ninety-two (42.8%) and 257 (57.2%) patients were female and male, respectively (mean: 41 years, r: 37-83). Patient satisfaction of the dispatcher was good, and satisfaction level in regards to the technicians' performance, physical situation, and facilities inside the ambulance was moderate. The Wilcoxon test did not show any significant difference between pain severity before and after arriving EMS in the cardiac and respiratory patients (p=0.691), but severity of pain in orthopedic patients after arriving EMS was decreased (p=0.001). Cardiac and respiratory patients had low satisfaction of EMS, and the Chi-square test was significant (p=0.001). Orthopedic patients had the most satisfaction of EMS. Generally, patients' satisfaction of EMS was low. Satisfaction with pain relief in orthopedic patients was better than pain relief in cardiac and respiratory patients. It is recommended to take necessary actions to improve the level of patient satisfaction of EMS.

How well will you FIT? Use of a modified MMI to assess applicants' compatibility with an emergency medicine residency program.

PubMed

Min, Alice A; Leetch, Aaron; Nuño, Tomas; Fiorello, Albert B

2016-01-01

Emergency medicine residency programs have evaluated the use of Multiple Mini Interviews (MMIs) for applicants. The authors developed an MMI-style method called the Fast Interview Track (FIT) to predict an applicant's 'fit' within an individual residency program. Applicants meet with up to five residents and are asked one question by each. Residents score the applicant using a Likert scale from 1 to 5 on two questions: 'How well does the applicant think on his/her feet?' and 'How well do you think the applicant will fit in here?'. To assess how well these questions predicted a resident's 'fit', current residents scored fellow residents on these same questions. These scores were compared with the residents' interview FIT scores. A postmatch survey of applicants who did not match at this program solicited applicants' attitudes toward the FIT sessions. Among the junior class, the correlation between interview and current scores was significant for question 1 (rho=0.5192 [p=0.03]) and question 2 (rho=0.5753 [p=0.01]). Among seniors, Spearman's rho was statistically significant for question 2, though not statistically significant for question 1. The chi-square measure of high scores (4-5) versus low scores (1-3) found a statistically significant association between interview and current scores for interns and juniors. Of the 29 responses to the postmatch survey, 16 (55%) felt FIT sessions provided a good sense of the program's personality and only 6 (21%) disagreed. Nine (31%) felt FIT sessions positively impacted our program's ranking and 11 (38%) were 'Neutral'. Only two (7%) reported that FIT sessions negatively impacted their ranking of our program. FIT provided program leadership with a sense of an applicant's 'fit' within this program. Interview day scores correlated with scores received during residency. Most applicants report a positive experience with FIT sessions. FIT provides a useful tool to recruit applicants who fit with the residency program.

How well will you FIT? Use of a modified MMI to assess applicants' compatibility with an emergency medicine residency program.

PubMed

Min, Alice A; Leetch, Aaron; Nuño, Tomas; Fiorello, Albert B

2016-01-01

Purpose Emergency medicine residency programs have evaluated the use of Multiple Mini Interviews (MMIs) for applicants. The authors developed an MMI-style method called the Fast Interview Track (FIT) to predict an applicant's 'fit' within an individual residency program. Methods Applicants meet with up to five residents and are asked one question by each. Residents score the applicant using a Likert scale from 1 to 5 on two questions: 'How well does the applicant think on his/her feet?' and 'How well do you think the applicant will fit in here?'. To assess how well these questions predicted a resident's 'fit', current residents scored fellow residents on these same questions. These scores were compared with the residents' interview FIT scores. A postmatch survey of applicants who did not match at this program solicited applicants' attitudes toward the FIT sessions. Results Among the junior class, the correlation between interview and current scores was significant for question 1 (rho=0.5192 [p=0.03]) and question 2 (rho=0.5753 [p=0.01]). Among seniors, Spearman's rho was statistically significant for question 2, though not statistically significant for question 1. The chi-square measure of high scores (4-5) versus low scores (1-3) found a statistically significant association between interview and current scores for interns and juniors. Of the 29 responses to the postmatch survey, 16 (55%) felt FIT sessions provided a good sense of the program's personality and only 6 (21%) disagreed. Nine (31%) felt FIT sessions positively impacted our program's ranking and 11 (38%) were 'Neutral'. Only two (7%) reported that FIT sessions negatively impacted their ranking of our program. Conclusions FIT provided program leadership with a sense of an applicant's 'fit' within this program. Interview day scores correlated with scores received during residency. Most applicants report a positive experience with FIT sessions. FIT provides a useful tool to recruit applicants who fit with the residency program.

Technical player profiles related to the physical fitness of young female volleyball players predict team performance.

PubMed

Dávila-Romero, C; Hernández-Mocholí, M A; García-Hermoso, A

2015-03-01

This study is divided into three sequential stages: identification of fitness and game performance profiles (individual player performance), an assessment of the relationship between these profiles, and an assessment of the relationship between individual player profiles and team performance during play (in championship performance). The overall study sample comprised 525 (19 teams) female volleyball players aged 12-16 years and a subsample (N.=43) used to examine study aims one and two was selected from overall sample. Anthropometric, fitness and individual player performance (actual game) data were collected in the subsample. These data were analyzed through clustering methods, ANOVA and independence chi-square test. Then, we investigated whether the proportion of players with the highest individual player performance profile might predict a team's results in the championship. Cluster analysis identified three volleyball fitness profiles (high, medium, and low) and two individual player performance profiles (high and low). The results showed a relationship between both types of profile (fitness and individual player performance). Then, linear regression revealed a moderate relationship between the number of players with a high volleyball fitness profile and a team's results in the championship (R2=0.23). The current study findings may enable coaches and trainers to manage training programs more efficiently in order to obtain tailor-made training, identify volleyball-specific physical fitness training requirements and reach better results during competitions.

VizieR Online Data Catalog: Transiting planet GJ 1132 (Southworth+, 2017)

NASA Astrophysics Data System (ADS)

Southworth, J.; Mancini, L.; Madhusudhan, N.; Molliere, P.; Ciceri, S.; Henning, T.

2018-05-01

Light curves of 10 transits of the extrasolar planetary system GJ 1132 are presented. The data were obtained using the MPG 2.2m telescope with GROND imager, and observed simultaneously in the g, r, i, z, J, H and K passbands. The errorbars for each transit have been scaled so the best-fitting model (obtained using the JKTEBOP code) has a reduced chi-squared value of 1.0. (1 data file).

Workplace Breastfeeding Support Varies by Employment Type: The Service Workplace Disadvantage.

PubMed

Snyder, Kailey; Hansen, Kelli; Brown, Sara; Portratz, Amy; White, Kate; Dinkel, Danae

The majority of women are returning to work full-time after childbirth, and support within their place of employment may influence intention and duration for breastfeeding, but more research is needed. Therefore, the purpose of this study was to explore the influence of employment type on breastfeeding duration upon return to work by examining informal (i.e., verbal encouragement) and direct (i.e., lactation space, flexible time) factors of support. This was a retrospective survey of women's returning-to-work experiences while breastfeeding. Survey contents included respondent demographics as well as questions surrounding perceptions of employer support, work environment, and goal/satisfaction regarding breastfeeding. Data were analyzed via crosstabs and chi-square goodness of fit tests. A total of 1,002 women completed the survey. Significant differences were seen across different employment types. Women within the professional/management industry were most likely to receive informal and direct support for breastfeeding upon return to work. Women within the service industry and production/transportation industry reported receiving the lowest levels of informal and direct support. Workplace support varies by employment type and women in the service and production/transportation industry appear to be at a disadvantage compared with other employment types. There is a need for more breastfeeding support programs to be developed that target specific workplace characteristics.

Nutritional Status of Rural Older Adults is Linked to Physical and Emotional Health

PubMed Central

Jung, Seung Eun; Bishop, Alex J; Kim, Minjung; Hermann, Janice; Kim, Giyeon; Lawrence, Jeannine

2017-01-01

Background Although nutritional status is influenced by multi-dimensional aspects encompassing physical and emotional well-being, there is limited research on this complex relationship. Objective The purpose of this study was to examine the interplay between indicators of physical health (perceived health status and self-care capacity) and emotional well-being (depressive affect and loneliness) on rural older adults’ nutritional status. Design The cross-sectional study was conducted from June 1, 2007 to June 1, 2008. Participants/setting A total of 171 community-dwelling older adults, 65 years and older, who resided within non-metro rural communities in the U.S. participated in this study. Main outcome measures Participants completed validated instruments measuring self-care capacity, perceived health status, loneliness, depressive affect, and nutritional status. Statistical analyses performed Structural equation modeling (SEM) was employed to investigate the complex interplay of physical and emotional health status with nutritional status among rural older adults, Chi-square statistic, CFI, RMSEA and SRMR were used to assess model fit. Results Chi-square statistic and the other model fit indices showed the hypothesized SEM model provided a good fit to the data (χ2 (2)=2.15, p=0.34; CFI=1.00; RMSEA=0.02; SRMR=0.03). Self-care capacity was significantly related with depressive affect (γ = −0.11, p=0.03) whereas self-care capacity was not significantly related with loneliness. Perceived health status had a significant negative relationship with both loneliness (γ = −0.16, p=0.03) and depressive affect (γ = −0.22, p=0.03). Although loneliness showed no significant direct relationship with nutritional status, it showed a significant direct relationship with depressive affect (β = 0.46, p<0.01). Finally, the results demonstrated that depressive affect had a significant negative relationship with nutritional status (β = −0.30, p<0.01). The results indicated physical health and emotional indicators have significant multi-dimensional associations with nutritional status among rural older adults. Conclusions The present study provides insights into the importance of addressing both physical and emotional well-being together to reduce potential effects of poor emotional well-being on nutritional status, particularly among rural older adults with impaired physical health and self-care capacity. PMID:28274787

Hospital mortality prediction for intermediate care patients: Assessing the generalizability of the Intermediate Care Unit Severity Score (IMCUSS).

PubMed

Hager, David N; Tanykonda, Varshitha; Noorain, Zeba; Sahetya, Sarina K; Simpson, Catherine E; Lucena, Juan Felipe; Needham, Dale M

2018-05-19

The Intermediate Care Unit Severity Score (IMCUSS) is an easy to calculate predictor of in-hospital death, and the only such tool developed for patients in the intermediate care setting. We sought to examine its external validity. Using data from patients admitted to the intermediate care unit (IMCU) of an urban academic medical center from July to December of 2012, model discrimination and calibration for predicting in-hospital death were assessed using the area under the receiver operating characteristic (AUROC) and the Hosmer-Lemeshow goodness-of-fit chi-squared (HL GOF X 2 ) test, respectively. The standardized mortality ratio (SMR) with 95% confidence intervals (95% CI) was also calculated. The cohort included data from 628 unique admissions to the IMCU. Overall hospital mortality was 8.3%. The median IMCUSS was 10 (Interquartile Range: 0-16), with 229 (36%) patients having a score of zero. The AUROC for the IMCUSS was 0.72 (95% CI: 0.64-0.78), the HL GOF X 2  = 30.7 (P < 0.001), and the SMR was 1.22 (95% CI: 0.91-1.60). The IMCUSS exhibited acceptable discrimination, poor calibration, and underestimated mortality. Other centers should assess the performance of the IMCUSS before adopting its use. Copyright © 2018. Published by Elsevier Inc.

Mexican Americans receive less intensive stroke rehabilitation than non Hispanic whites

PubMed Central

Morgenstern, Lewis B.; Sais, Emma; Fuentes, Michael; Ifejika, Nneka L.; Jiang, Xiaqing; Horn, Susan D.; Case, Erin; Lisabeth, Lynda D.

2017-01-01

Background and Purpose Mexican Americans (MAs) have worse neurologic, functional and cognitive outcomes after stroke. Stroke rehabilitation is important for good outcome. In a population-based study, we sought to determine if allocation of stroke rehabilitation services differed by ethnicity. Methods Stroke patients were identified as part of the Brain Attack Surveillance in Corpus Christi (BASIC) project, Texas, USA. Cases were validated by physicians using source documentation. Patients were followed prospectively for three months following stroke to determine rehabilitation services and transitions. Descriptive statistics were used to depict the study population. Continuous baseline variables were compared using two sample t-tests or Wilcoxon rank-sum tests by ethnicity. Categorical baseline variables were compared using chi-squared tests. Ethnic comparisons of rehabilitation services were compared using chi-squared tests, Fisher’s exact tests and logistic regression. Results Seventy-two subjects (50 MA and 22 non-Hispanic white [NHW]) were followed. Mean age, NHW-69 (sd-13), MA-66 (sd-11) years, sex (NHW 55% male, MA 50% male) and median presenting NIHSS did not differ significantly. There were no ethnic differences among the proportion of patients who were sent home without any rehabilitation services (p=0.9). Among those who received rehabilitation NHWs were more likely to get inpatient rehabilitation (73%) compared with MAs (30%), p=0.016. MAs (51%) were much more likely to receive home rehabilitation services compared with NHWs (0%) (p=0.0017). Conclusions In this population-based study, MAs were more likely to receive home-based rehabilitation while NHWs more likely to get inpatient rehabilitation. This disparity may, in part, explain the worse stroke outcome in MAs. PMID:28386042

Sorption equilibrium of mercury onto ground-up tree fern.

PubMed

Ho, Yuh-Shan; Wang, Chung-Chi

2008-08-15

The sorption behavior of mercury at different temperatures onto ground-up tree fern was investigated. The experimental results were fitted to two two-parameter isotherms, the Freundlich and Langmuir isotherms, as well as to two three-parameter isotherms, the Redlich-Peterson and Sips isotherms to obtain the characteristic parameters of each model. A comparison of best-fitting was performed using the coefficient of determination and Chi-square test. Both the Langmuir and Redlich-Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of mercury ions onto ground-up tree fern was 26.5 mg/g at 298 K. It was noted that an increase in temperature resulted in a higher mercury ion loading per unit weight of the tree fern. In addition, various thermodynamic parameters, such as DeltaG degrees, DeltaH degrees, and DeltaS degrees, were calculated and compared with the sorption of mercury by other sorbents.

Evidence of Syndemics and Sexuality-Related Discrimination Among Young Sexual-Minority Women.

PubMed

Coulter, Robert W S; Kinsky, Suzanne M; Herrick, Amy L; Stall, Ron D; Bauermeister, José A

2015-09-01

Syndemics, or the co-occurrence and interaction of health problems, have been examined extensively among young men who have sex with men, but their existence remain unexamined, to our knowledge, among sexual-minority (i.e., lesbian, gay, and bisexual) women. Thus, we investigated if syndemics were present among young sexual-minority women, and if sexual-orientation discrimination was an independent variable of syndemic production. A total of 467 sexual-minority women between the ages of 18 and 24 completed a cross-sectional online survey regarding their substance use, mental health, sexual behaviors, height, weight, and experiences of discrimination. We used structural equation modeling to investigate the presence of syndemics and their relationship to sexual-orientation discrimination. Heavy episodic drinking, marijuana use, ecstasy use, hallucinogen use, depressive symptoms, multiple sexual partners, and history of sexually transmitted infections (STIs) comprised syndemics in this population (chi-square=24.989, P=.201; comparative fit index [CFI]=0.946; root mean square error of approximation [RMSEA]=0.023). Sexual-orientation discrimination is significantly and positively associated with the latent syndemic variable (unstandardized coefficient=0.095, P<.05), and this model fit the data well (chi-square=33.558, P=.059; CFI=0.914; RMSEA=0.029). The reverse causal model showed syndemics is not an independent variable of sexual-orientation discrimination (unstandardized coefficient=0.602, P>.05). Syndemics appear to be present and associated with sexual-orientation discrimination among young sexual-minority women. Interventions aimed at reducing discrimination or increasing healthy coping may help reduce substance use, depressive symptoms, and sexual risk behaviors in this population.

The Mentoring Competency Assessment: validation of a new instrument to evaluate skills of research mentors.

PubMed

Fleming, Michael; House, Stephanie; Hanson, Vansa Shewakramani; Yu, Lan; Garbutt, Jane; McGee, Richard; Kroenke, Kurt; Abedin, Zainab; Rubio, Doris M

2013-07-01

To determine the psychometric properties of the Mentoring Competency Assessment (MCA), a 26-item skills inventory that enables research mentors and mentees to evaluate six competencies of mentors: maintaining effective communication, aligning expectations, assessing understanding, addressing diversity, fostering independence, and promoting professional development. In 2010, investigators administered the MCA to 283 mentor-mentee pairs from 16 universities participating in a trial of a mentoring curriculum for clinical and translational research mentors. The authors analyzed baseline MCA data to describe the instrument's psychometric properties. Coefficient alpha scores for the MCA showed reliability (internal consistency). The hypothesized model with its six latent constructs (competencies) resulted in an acceptable fit to the data. For the instrument completed by mentors, chi-square = 663.20; df = 284; P < .001; root mean square error of approximation (RMSEA) = 0.069 (90% CI, 0.062-0.076); comparative fit index (CFI) = 0.85; and Tucker-Lewis index (TLI) = 0.83. For the instrument completed by mentees, chi-square = 840.62; df = 284; P < .001; RMSEA = 0.080 (90% CI, 0.063-0.077); CFI = 0.87; and TLI = 0.85. The correlations among the six competencies were high: 0.49-0.87 for mentors, 0.58-0.92 for mentees. All parameter estimates for the individual items were significant; standardized factor loadings ranged from 0.32 to 0.81 for mentors and 0.56 to 0.86 for mentees. The findings demonstrate that the MCA has reliability and validity. In addition, this study provides preliminary norms derived from a national sample of mentors and mentees.

Relationship between long working hours and depression: a 3-year longitudinal study of clerical workers.

PubMed

Amagasa, Takashi; Nakayama, Takeo

2013-08-01

To clarify how long working hours affect the likelihood of current and future depression. Using data from four repeated measurements collected from 218 clerical workers, four models associating work-related factors to the depressive mood scale were established. The final model was constructed after comparing and testing the goodness-of-fit index using structural equation modeling. Multiple logistic regression analysis was also performed. The final model showed the best fit (normed fit index = 0.908; goodness-of-fit index = 0.936; root-mean-square error of approximation = 0.018). Its standardized total effect indicated that long working hours affected depression at the time of evaluation and 1 to 3 years later. The odds ratio for depression risk was 14.7 in employees who were not long-hours overworked according to the initial survey but who were long-hours overworked according to the second survey. Long working hours increase current and future risks of depression.

[Hospitalization period and nutritional status in hospitalized patients].

PubMed

Merhi, V A Leandro; de Oliveira, Ma R Marques; Caran, A L; Tristão, T Menuzzo Graupner; Ambo, R Miante; Tanner, M A; Vergna, C Marton

2007-01-01

With the objective of studying the nutritional status and its relationship with hospitalization period, a cross-sectional study was done with patients from a private hospital representing a population with a better socioeconomic condition. The anthropometric data of 267 patients, 46% males and 54% females ranging from 20 to 80 years of age, were assessed on the second day of hospitalization. Hospitalization period associated with nutritional status. The data were analyzed by the software Excel and Sigma Stat, using Fisher's exact test and the chi-square test. The studied population presented a body mass index of 25.9 +/- 5.3 and most patients lost weight during hospitalization. The longest hospitalization periods were found among patients with lung diseases (13 days), some being pre-obese (40%) with a small prevalence of undernutrition (4%). The percentage distribution of nutritional status among the groups according to diagnosis was different (P < 0.01) when assessed by the Fisher's exact test and the percentage distribution in weight variation between men and women was different (P < 0.02) when assessed by the chi-square test. When the population was segmented according to age, the percentage distribution of the nutritional status between > 60 and < or = 60 did not present a difference when assessed by the chi-square test. The results of this study show that the nutritional status in some diseases deserves special attention given the greater risk found in these situations, contributing to a longer hospitalization period.

[Music therapy and regional anesthesia in orthopedic surgery].

PubMed

Rupérez Ruiz, Ma Pilar; De San José, Isabel; Hermoso Montoya, Anna; Ferreira Valencia, Teresa; Gómez Sanz, Amelia; López Gutiérrez, Anna

2014-06-01

To evaluate the sedative effects, intra-operation, of music therapy in orthopedic surgery patients with locoregional anesthesia in the Hospital Clínic i Provincial of Barcelona. Prospective comparative study on a random sample of 110 patients undergoing or not music therapy. The degree of anxiety was assessed with the Questionnaire STAIC. The application of the music was done with a MP3 player and headphones. The collected data were analyzed with Excel. For the statistical analysis we used the SPSS-18 software and Chi-square test to test the hypothesis of whether there was relationship between the level of peace and music therapy. After the analysis, the results of Chi-square were in the group of no sedation with/without music Chi2 = 2.01, P = 0.35. The statistical significance level was p < 0.05. No relationship was found between hearing music or not and the patient's comfort level. Most patients recommend listening to music in the operating room despite the sounds around do not bother them.

Does clinical pretest probability influence image quality and diagnostic accuracy in dual-source coronary CT angiography?

PubMed

Thomas, Christoph; Brodoefel, Harald; Tsiflikas, Ilias; Bruckner, Friederike; Reimann, Anja; Ketelsen, Dominik; Drosch, Tanja; Claussen, Claus D; Kopp, Andreas; Heuschmid, Martin; Burgstahler, Christof

2010-02-01

To prospectively evaluate the influence of the clinical pretest probability assessed by the Morise score onto image quality and diagnostic accuracy in coronary dual-source computed tomography angiography (DSCTA). In 61 patients, DSCTA and invasive coronary angiography were performed. Subjective image quality and accuracy for stenosis detection (>50%) of DSCTA with invasive coronary angiography as gold standard were evaluated. The influence of pretest probability onto image quality and accuracy was assessed by logistic regression and chi-square testing. Correlations of image quality and accuracy with the Morise score were determined using linear regression. Thirty-eight patients were categorized into the high, 21 into the intermediate, and 2 into the low probability group. Accuracies for the detection of significant stenoses were 0.94, 0.97, and 1.00, respectively. Logistic regressions and chi-square tests showed statistically significant correlations between Morise score and image quality (P < .0001 and P < .001) and accuracy (P = .0049 and P = .027). Linear regression revealed a cutoff Morise score for a good image quality of 16 and a cutoff for a barely diagnostic image quality beyond the upper Morise scale. Pretest probability is a weak predictor of image quality and diagnostic accuracy in coronary DSCTA. A sufficient image quality for diagnostic images can be reached with all pretest probabilities. Therefore, coronary DSCTA might be suitable also for patients with a high pretest probability. Copyright 2010 AUR. Published by Elsevier Inc. All rights reserved.

Determinants of moderate to vigorous physical activity and obesity in children: a structural equation modeling analysis.

PubMed

Yeung, Daniel Chi-Shing; Yuan, Xin; Hui, Stanley Sai-Chuen; Feresu, Shingairai Aliifina

2016-05-01

The determinants of physical activity (PA) and body fatness in Chinese adolescents are rarely examined. This study aimed to investigate the effect of attitude toward PA, screen time, parents' socioeconomic status (SES), and exercise habit on PA and body fatness among Chinese children by using structural equation modeling (SEM) analysis. Data obtained from the second Community Fitness Survey in Hong Kong were utilized, in which students from one secondary school of each of the 18 districts of Hong Kong were recruited. A total of 2517 questionnaires with physical fitness items were successfully distributed to students aged 13-19 years in these districts. Families' SES, parents' exercise habit, children's intention to participate in PA, amount of moderate to vigorous PA (MVPA), screen time, children's attitude toward PA, and children's body fat percentage were measured and analyzed with SEM. The structural equation model was composed of a measurement model and a structural model. The model was tested with Mplus 6. The Chi-square test, root mean square error of approximation, comparative fit index, and Tucker-Lewis index were calculated to evaluate model fit. The model was then modified based on the model fit indices. Children's intention to participate in PA was a strong predictor of their engagement in MVPA. Parents' exercise habit had both direct and indirect (via attitude) effects on their children's intention to participate in PA. Screen time was not a predictor of body composition. Children's intention to participate in PA directly affected their body composition. Children's attitude toward PA, parents' exercise habit, and SES had significant effects on the children's intention to participate in PA. Furthermore, obesity had a negative effect on the children's attitude toward PA. To promote MVPA and prevent obesity in Chinese children of Hong Kong, it is important to design intervention that enhances children's intention and attitude in PA, as well as parent's exercise habits. Tailormade programs that take SES into consideration are also essential. Further studies are necessary to extend the results and test the model in other metropolitan areas in China.

The Effect of Number of Ability Intervals on the Stability of Item Bias Detection.

ERIC Educational Resources Information Center

Loyd, Brenda

The chi-square procedure has been suggested as a viable index of test bias because it provides the best agreement with the three parameter item characteristic curve without the large sample requirement, computer complexity, and cost. This study examines the effect of using different numbers of ability intervals on the reliability of chi-square…

Psychometric evaluation of the muscle appearance satisfaction scale in a Mexican male sample.

PubMed

Escoto Ponce de León, María Del Consuelo; Bosques-Brugada, Lilián Elizabeth; Camacho Ruiz, Esteban Jaime; Alvarez-Rayón, Georgina; Franco Paredes, Karina; Rodríguez Hernández, Gabriela

2017-03-02

The purpose of this study was to determine whether the muscle appearance satisfaction scale (MASS) shows acceptable psychometric properties in Mexican bodybuilders. A total of 258 Mexican male bodybuilders were recruited. Two self-report questionnaires, including the MASS and drive for muscularity scale (DMS), were administered. Six models of the latent structure of the MASS were evaluated, using confirmatory factor analysis with maximum likelihood, considering robust Satorra-Bentler correction to estimate the fit of the models to the data. Similar to the original MASS, the series of CFA confirmed that the Mexican version was well represented with the 17-item five-factor structure, which showed a good model fit [Satorra-Bentler Chi-square (109, n = 258) = 189.18, p < 0.0001; NNFI = 0.91; CFI = 0.93; IFI = 0.93; RMSEA = 0.05 (0.04, 0.07)]. Internal consistency was estimated with McDonald's omega, which was acceptable for the MASS (0.88), and their subscales (0.80 to 0.89), except for muscle checking scale (0.77). Test-retest reliability analysis showed stability of the MASS total as well as of the subscale scores over a 2-week period (intraclass correlation coefficients = 0.75-0.91). Construct validity was demonstrated by a significant positive correlation between MASS and DMS results (r = 0.75; p = 0.0001). These results were similar to those of previous studies, which demonstrate the scale's usefulness. Our results support the suitability of the MASS and its subscales to measure muscle dysmorphia symptoms in Mexican male bodybuilders.

Pearson's chi-square test and rank correlation inferences for clustered data.

PubMed

Shih, Joanna H; Fay, Michael P

2017-09-01

Pearson's chi-square test has been widely used in testing for association between two categorical responses. Spearman rank correlation and Kendall's tau are often used for measuring and testing association between two continuous or ordered categorical responses. However, the established statistical properties of these tests are only valid when each pair of responses are independent, where each sampling unit has only one pair of responses. When each sampling unit consists of a cluster of paired responses, the assumption of independent pairs is violated. In this article, we apply the within-cluster resampling technique to U-statistics to form new tests and rank-based correlation estimators for possibly tied clustered data. We develop large sample properties of the new proposed tests and estimators and evaluate their performance by simulations. The proposed methods are applied to a data set collected from a PET/CT imaging study for illustration. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Clinical, biochemical, and hematological characteristics, disease prevalence, and prognosis of dogs presenting with neutrophil cytoplasmic toxicity.

PubMed

Aroch, Itamar; Klement, Eyal; Segev, Gilad

2005-01-01

Neutrophil cytoplasmic toxicity is manifested as an abnormality in cell size or the cytoplasmic content upon examination of Romanowsky-stained blood smears, and is traditionally associated with infection and inflammation. The purpose of this retrospective study was to investigate the association of such changes with clinical and clinicopathologic characteristics, diseases, and prognoses in dogs. Dogs with neutrophil toxicity (n = 248) were compared with negative controls (n = 248). Statistical analyses included chi-square tests, independent t-tests, nonparametric Mann-Whitney tests, the chi-square trend test, and survival analysis. Dogs with neutrophil toxicity had a significantly higher prevalence of pale mucous membranes, tachycardia, fever, abdominal organomegaly, icterus, melena, and hematuria. Most mean hematologic variables were significantly different between groups. Dogs with neutrophil toxicity had a significantly (P < .05) higher prevalence of leukocytosis, leukopenia, neutrophilia, neutropenia, anemia, hyponatremia, hypokalemia, hypoproteinemia, hypoalbuminemia, and hypocalcemia. The prevalence of pyometra, parvovirus infection, acute renal failure, peritonitis, immune-mediated hemolytic anemia, disseminated intravascular coagulation, pancreatitis, septicemia, and neoplastic disorders was significantly higher among these dogs. Case fatality, hospitalization length, and treatment cost were significantly (P < .001) higher in dogs with neutrophil toxicity. Neutrophil toxicity severity was significantly (P < .0035) and positively associated with neutropenia, and negatively associated with leukocytosis and neutrophilia. A significant trend (P = .05) toward increasing case fatality with an increase of neutrophil toxicity was observed. In the neutrophil toxicity group, dogs with leukopenia (<5.0 X 10(3)/mm3) had a significantly (P < .0001) higher case fatality compared to dogs with normal or high leukocyte counts. We conclude that evaluation of blood smears for neutrophil cytoplasmic toxicity provides useful clinical information and can serve as a good prognostic predictor.

On-road assessment of fitness-to-drive in persons with MS with cognitive impairment: A prospective study.

PubMed

Morrow, Sarah A; Classen, Sherrilene; Monahan, Miriam; Danter, Tim; Taylor, Robert; Krasniuk, Sarah; Rosehart, Heather; He, Wenqing

2017-08-01

Cognitive impairment is common in multiple sclerosis (MS). In other populations, cognitive impairment is known to affect fitness-to-drive. Few studies have focused on fitness-to-drive in MS and no studies have solely focused on the influence of cognitive impairment. To assess fitness-to-drive in persons with MS with cognitive impairment and low physical disability. Persons with MS, aged 18-59 years with EDSS ⩽ 4.0, impaired processing speed, and impairment on at least one measure of memory or executive function, were recruited. Cognition was assessed using the Minimal Assessment of Cognitive Function battery. A formal on-road driving assessment was conducted. Chi-square analysis examined the association between the fitness-to-drive (pass/fail) and the neuropsychological test results (normal/impaired). Bayesian statistics predicting failure of the on-road assessment were calculated. Of 36 subjects, eight (22.2%) were unfit to drive. Only the BVMTR-IR, measuring visual-spatial memory, predicted on-road driving assessment failure ( X 2 ( df = 1, N = 36) = 3.956; p = 0.047) with a sensitivity of 100%, but low specificity (35.7%) due to false positives (18/25). In persons with MS and impaired processing speed, impairment on the BVMTR-IR should lead clinicians to address fitness-to-drive.

VizieR Online Data Catalog: Transiting planet WASP-6b (Tregloan-Reed+, 2015)

NASA Astrophysics Data System (ADS)

Tregloan-Reed, J.; Southworth, J.; Burgdorf, M.; Calchi Novati, S.; Dominik, M.; Finet, F.; Jorgensen, U. G.; Maier, G.; Mancini, L.; Prof, S.; Ricci, D.; Snodgrass, C.; Bozza, V.; Browne, P.; Dodds, P.; Gerner, T.; Harpsoe, K.; Hinse, T. C.; Hundertmark, M.; Kains, N.; Kerins, E.; Liebig, C.; Penny, M. T.; Rahvar, S.; Sahu, K.; Scarpetta, G.; Schafer, S.; Schonebeck, F.; Skottfelt, J.; Surdej, J.

2018-05-01

Four light curves of transits of the extrasolar planetary system WASP-6 are presented. They were obtained using the Danish 1.54m telescope at ESO La Silla, Chile, in the Bessell R passband. The errorbars for each transit have been scaled so the best-fitting model (obtained using the JKTEBOP code and without accounting for the presence of starspots) has a reduced chi-squared value of 1.0. (1 data file).

The impact of prism adaptation test on surgical outcomes in patients with primary exotropia.

PubMed

Kiyak Yilmaz, Ayse; Kose, Suheyla; Guven Yilmaz, Suzan; Uretmen, Onder

2015-05-01

We aimed to determine the impact of the preoperative prism adaptation test (PAT) on surgical outcomes in patients with primary exotropia. Thirty-eight consecutive patients with primary exotropia were enrolled. Pre-operative PAT was performed in 18 randomly selected patients (Group 1). Surgery was based on the angle of deviation at distance measured after PAT. The remaining 20 patients in whom PAT was not performed comprised Group 2. Surgery was based on the angle of deviation at distance in these patients. Surgical success was defined as ocular alignment within eight prism dioptres (PD) of orthophoria. Satisfactory motor alignment (± 8 PD) was achieved in 16 Group 1 patients (88.9 per cent) and 16 Group 2 patients (80 per cent) one year after surgery (p = 0.6; chi-square test). There were no statistically significant differences in demographic parameters, pre-operative and post-operative angle of deviation between the two groups (p > 0.05; Mann-Whitney U and chi-square tests). Nine patients in Group 1 (50 per cent) and two patients in Group 2 (10 per cent) had increased binocular vision one year post-operatively. A statistically significant difference was determined in terms of change in binocular single vision between the two groups (p = 0.01; chi-square test). Although the prism adaptation test did not lead to a significant increment in motor success, it may be helpful in achieving a more favourable functional surgical outcome in patients with primary exotropia. © 2014 The Authors. Clinical and Experimental Optometry © 2014 Optometrists Association Australia.

Relationship between long working hours and depression in two working populations: a structural equation model approach.

PubMed

Amagasa, Takashi; Nakayama, Takeo

2012-07-01

To test the hypothesis that relationship reported between long working hours and depression was inconsistent in previous studies because job demand was treated as a confounder. Structural equation modeling was used to construct five models, using work-related factors and depressive mood scale obtained from 218 clerical workers, to test for goodness of fit and was externally validated with data obtained from 1160 sales workers. Multiple logistic regression analysis was also performed. The model that showed that long working hours increased depression risk when job demand was regarded as an intermediate variable was the best fitted model (goodness-of-fit index/root-mean-square error of approximation: 0.981 to 0.996/0.042 to 0.044). The odds ratio for depression risk with work that was high demand and 60 hours or more per week was estimated at 2 to 4 versus work that was low demand and less than 60 hours per week. Long working hours increased depression risk, with job demand being an intermediate variable.

[Establishment of Assessment Method for Air Bacteria and Fungi Contamination].

PubMed

Zhang, Hua-ling; Yao, Da-jun; Zhang, Yu; Fang, Zi-liang

2016-03-15

In this paper, in order to settle existing problems in the assessment of air bacteria and fungi contamination, the indoor and outdoor air bacteria and fungi filed concentrations by impact method and settlement method in existing documents were collected and analyzed, then the goodness of chi square was used to test whether these concentration data obeyed normal distribution at the significant level of α = 0.05, and combined with the 3σ principle of normal distribution and the current assessment standards, the suggested concentrations ranges of air microbial concentrations were determined. The research results could provide a reference for developing air bacteria and fungi contamination assessment standards in the future.

Public secondary school teachers' attitude to family life education in two geopolitical zones of Nigeria: a comparative analysis.

PubMed

Okusanya, B O; Isabu, P A

2010-03-01

This qualitative study was conducted to assess and compare the attitude of teachers in two geopolitical zones of Nigeria to family life education. Multi stage sample selection was used to pick 6 public secondary schools (3 junior, 3 senior) in each zone. All teachers (221) in the selected schools were surveyed. Pre-tested questionnaires were self administered, responses analyzed and results presented using descriptive frequencies. Where appropriate statistical evaluation was done with Yates corrected Chi square at 95% confidence interval. Katsina respondents were mostly Muslims (92.4%), married (64.8%) and had the National Certificate of Education (62.9%). Ekpoma teachers were mostly Christians (97.4%), married (93.1%) and 67.2% had a University degree. Attendance at a seminar on family life education was by 19% and 25.9% of respondents from Katsina and Ekpoma respectively. Teachers' knowledge of family life education was very good and most teachers in both regions considered it useful but there were geographical disparities in perception and attitude. While teachers in Katsina discussed HIV/AIDS twice more with their students than sexuality (54.3% vs 28%) those in Ekpoma discussed sexuality more than HIV/AIDS (80.2% vs 72.4%). Respondents in Katsina reported three times (60% vs 19.8%) more that parents would object to FLE in schools than those in Ekpoma and also that its introduction would encourage promiscuity amongst the students (53.3% vs 21.6%). While being married positively influenced respondents' perception, their attitude was influenced positively by having university degree and teaching at the senior secondary school. Christians significantly discussed sexuality (Chi square 58.60; RR: 3.03) and HIV/AIDS (Chi square 15.01; RR: 1.50) with students than Muslims. Policy makers need to be aware of the regional differences in teachers' attitude to family life education as this may hinder the implementation of curriculum.

Testing for independence in J×K contingency tables with complex sample survey data.

PubMed

Lipsitz, Stuart R; Fitzmaurice, Garrett M; Sinha, Debajyoti; Hevelone, Nathanael; Giovannucci, Edward; Hu, Jim C

2015-09-01

The test of independence of row and column variables in a (J×K) contingency table is a widely used statistical test in many areas of application. For complex survey samples, use of the standard Pearson chi-squared test is inappropriate due to correlation among units within the same cluster. Rao and Scott (1981, Journal of the American Statistical Association 76, 221-230) proposed an approach in which the standard Pearson chi-squared statistic is multiplied by a design effect to adjust for the complex survey design. Unfortunately, this test fails to exist when one of the observed cell counts equals zero. Even with the large samples typical of many complex surveys, zero cell counts can occur for rare events, small domains, or contingency tables with a large number of cells. Here, we propose Wald and score test statistics for independence based on weighted least squares estimating equations. In contrast to the Rao-Scott test statistic, the proposed Wald and score test statistics always exist. In simulations, the score test is found to perform best with respect to type I error. The proposed method is motivated by, and applied to, post surgical complications data from the United States' Nationwide Inpatient Sample (NIS) complex survey of hospitals in 2008. © 2015, The International Biometric Society.

HIV/AIDS knowledge and its implications on dentists

PubMed Central

Prabhu, Anand; Rao, Arun Prasad; Reddy, Venugopal; Krishnakumar, Ramalingam; Thayumanavan, Shanmugam; Swathi, Silla Swarna

2014-01-01

Aims and Objectives: The aim of the present study was to evaluate the knowledge of dentists regarding human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Materials and Methods: A structured questionnaire to evaluate the knowledge, fears, and attitudes was self administered to 102 dentists. The data was then evaluated using Chi-square test and a P < 0.05 was considered statistically significant. Results and Conclusion: The findings of the present study suggest that dentists in private practice and affiliated with teaching institutions, had better knowledge than their counterparts who were into private practice alone. It was concluded that despite good knowledge many of the dentists expressed some hesitation in treating patients with HIV/AIDS. PMID:25097403

Does Positivity Mediate the Relation of Extraversion and Neuroticism with Subjective Happiness?

PubMed Central

Lauriola, Marco; Iani, Luca

2015-01-01

Recent theories suggest an important role of neuroticism, extraversion, attitudes, and global positive orientations as predictors of subjective happiness. We examined whether positivity mediates the hypothesized relations in a community sample of 504 adults between the ages of 20 and 60 years old (females = 50%). A model with significant paths from neuroticism to subjective happiness, from extraversion and neuroticism to positivity, and from positivity to subjective happiness fitted the data (Satorra–Bentler scaled chi-square (38) = 105.91; Comparative Fit Index = .96; Non-Normed Fit Index = .95; Root Mean Square Error of Approximation = .060; 90% confidence interval = .046, .073). The percentage of subjective happiness variance accounted for by personality traits was only about 48%, whereas adding positivity as a mediating factor increased the explained amount of subjective happiness to 78%. The mediation model was invariant by age and gender. The results show that the effect of extraversion on happiness was fully mediated by positivity, whereas the effect of neuroticism was only partially mediated. Implications for happiness studies are also discussed. PMID:25781887

Lysine clonixinate in minor dental surgery: double-blind randomized parallel study versus paracetamol.

PubMed

Martí, M L; De los Santos, A R; Di Girolamo, G; Gil, M; Manero, E O; Fraga, C

1993-01-01

Lysine clonixinate (LC), an effective and well tolerated non-morphinic analgesic whose mechanism of action is basically due to the inhibition of cyclo-oxygenase, was assessed with a double-blind randomized dummy design versus paracetamol (P) on 200 patients suffering from pain after minor dental surgery. Patients received according to their needs 1 or 2 tablets of 125 mg lysine clonixinate or 500 mg paracetamol every 8 h during 48 h or until pain relief. Both groups, each composed of 100 patients, were comparable in terms of demographic conditions (t test), initial symptoms (chi-square test), characteristics of the extracted dental pieces, surgical complications and wound treatment (chi-square test). Pain intensity scores and daily average intake of tablets (3.4/day) documented in the patients' diary revealed no statistically significant differences between the two treatments (chi-square test). It was found that spontaneous pain measured using a visual analogue scale (VAS) decreased significantly in both treatment groups at the 24-h control examination. The following values were observed in the LC group: baseline 4.38 +/- 1.7; 24-h * 1.20 +/- 1.4; 48-h * 0.36 +/- 1.2. In the P group the values were: baseline 4.28 +/- 1.6; 24-h * 1.11 +/- 1.4; 48-h * 0.30 +/- 0.7 (*p < 0.05). Other variables like facial swelling and night pain, evaluated on a score from 0 to 4 and symptom presence or absence respectively, showed a similar response.(ABSTRACT TRUNCATED AT 250 WORDS)

Measuring teacher self-report on classroom practices: Construct validity and reliability of the Classroom Strategies Scale-Teacher Form.

PubMed

Reddy, Linda A; Dudek, Christopher M; Fabiano, Gregory A; Peters, Stephanie

2015-12-01

This article presents information about the construct validity and reliability of a new teacher self-report measure of classroom instructional and behavioral practices (the Classroom Strategies Scales-Teacher Form; CSS-T). The theoretical underpinnings and empirical basis for the instructional and behavioral management scales are presented. Information is provided about the construct validity, internal consistency, test-retest reliability, and freedom from item-bias of the scales. Given previous investigations with the CSS Observer Form, it was hypothesized that internal consistency would be adequate and that confirmatory factor analyses (CFA) of CSS-T data from 293 classrooms would offer empirical support for the CSS-T's Total, Composite and subscales, and yield a similar factor structure to that of the CSS Observer Form. Goodness-of-fit indices of χ2/df, Root Mean Square Error of Approximation, Goodness of Fit Index, and Adjusted Goodness of Fit Index suggested satisfactory fit of proposed CFA models whereas the Comparative Fit Index did not. Internal consistency estimates of .93 and .94 were obtained for the Instructional Strategies and Behavioral Strategies Total scales respectively. Adequate test-retest reliability was found for instructional and behavioral total scales (r = .79, r = .84, percent agreement 93% and 93%). The CSS-T evidences freedom from item bias on important teacher demographics (age, educational degree, and years of teaching experience). Implications of results are discussed. (c) 2015 APA, all rights reserved).

Validation of the LOD score compared with APACHE II score in prediction of the hospital outcome in critically ill patients.

PubMed

Khwannimit, Bodin

2008-01-01

The Logistic Organ Dysfunction score (LOD) is an organ dysfunction score that can predict hospital mortality. The aim of this study was to validate the performance of the LOD score compared with the Acute Physiology and Chronic Health Evaluation II (APACHE II) score in a mixed intensive care unit (ICU) at a tertiary referral university hospital in Thailand. The data were collected prospectively on consecutive ICU admissions over a 24 month period from July1, 2004 until June 30, 2006. Discrimination was evaluated by the area under the receiver operating characteristic curve (AUROC). The calibration was assessed by the Hosmer-Lemeshow goodness-of-fit H statistic. The overall fit of the model was evaluated by the Brier's score. Overall, 1,429 patients were enrolled during the study period. The mortality in the ICU was 20.9% and in the hospital was 27.9%. The median ICU and hospital lengths of stay were 3 and 18 days, respectively, for all patients. Both models showed excellent discrimination. The AUROC for the LOD and APACHE II were 0.860 [95% confidence interval (CI) = 0.838-0.882] and 0.898 (95% Cl = 0.879-0.917), respectively. The LOD score had perfect calibration with the Hosmer-Lemeshow goodness-of-fit H chi-2 = 10 (p = 0.44). However, the APACHE II had poor calibration with the Hosmer-Lemeshow goodness-of-fit H chi-2 = 75.69 (p < 0.001). Brier's score showed the overall fit for both models were 0.123 (95%Cl = 0.107-0.141) and 0.114 (0.098-0.132) for the LOD and APACHE II, respectively. Thus, the LOD score was found to be accurate for predicting hospital mortality for general critically ill patients in Thailand.

Use of Pearson's Chi-Square for Testing Equality of Percentile Profiles across Multiple Populations.

PubMed

Johnson, William D; Beyl, Robbie A; Burton, Jeffrey H; Johnson, Callie M; Romer, Jacob E; Zhang, Lei

2015-08-01

In large sample studies where distributions may be skewed and not readily transformed to symmetry, it may be of greater interest to compare different distributions in terms of percentiles rather than means. For example, it may be more informative to compare two or more populations with respect to their within population distributions by testing the hypothesis that their corresponding respective 10 th , 50 th , and 90 th percentiles are equal. As a generalization of the median test, the proposed test statistic is asymptotically distributed as Chi-square with degrees of freedom dependent upon the number of percentiles tested and constraints of the null hypothesis. Results from simulation studies are used to validate the nominal 0.05 significance level under the null hypothesis, and asymptotic power properties that are suitable for testing equality of percentile profiles against selected profile discrepancies for a variety of underlying distributions. A pragmatic example is provided to illustrate the comparison of the percentile profiles for four body mass index distributions.

A note on the SG( m) test

NASA Astrophysics Data System (ADS)

López, Fernando A.; Matilla-García, Mariano; Mur, Jesús; Páez, Antonio; Ruiz, Manuel

2016-01-01

López et al. (Reg Sci Urban Econ 40(2-3):106-115, 2010) introduce a nonparametric test of spatial dependence, called SG( m). The test is claimed to be consistent and asymptotically Chi-square distributed. Elsinger (Reg Sci Urban Econ 43(5):838-840, 2013) raises doubts about the two properties. Using a particular counterexample, he shows that the asymptotic distribution of the SG( m) test may be far from the Chi-square family; the property of consistency is also questioned. In this note, the authors want to clarify the properties of the SG( m) test. We argue that the cause of the conflict is in the specification of the symbolization map. The discrepancies can be solved by adjusting some of the definitions made in the original paper. Moreover, we introduce a permutational bootstrapped version of the SG( m) test, which is powerful and robust to the underlying statistical assumptions. This bootstrapped version may be very useful in an applied context.

Classifier for gravitational-wave inspiral signals in nonideal single-detector data

NASA Astrophysics Data System (ADS)

Kapadia, S. J.; Dent, T.; Dal Canton, T.

2017-11-01

We describe a multivariate classifier for candidate events in a templated search for gravitational-wave (GW) inspiral signals from neutron-star-black-hole (NS-BH) binaries, in data from ground-based detectors where sensitivity is limited by non-Gaussian noise transients. The standard signal-to-noise ratio (SNR) and chi-squared test for inspiral searches use only properties of a single matched filter at the time of an event; instead, we propose a classifier using features derived from a bank of inspiral templates around the time of each event, and also from a search using approximate sine-Gaussian templates. The classifier thus extracts additional information from strain data to discriminate inspiral signals from noise transients. We evaluate a random forest classifier on a set of single-detector events obtained from realistic simulated advanced LIGO data, using simulated NS-BH signals added to the data. The new classifier detects a factor of 1.5-2 more signals at low false positive rates as compared to the standard "reweighted SNR" statistic, and does not require the chi-squared test to be computed. Conversely, if only the SNR and chi-squared values of single-detector events are available, random forest classification performs nearly identically to the reweighted SNR.

The recovery of weak impulsive signals based on stochastic resonance and moving least squares fitting.

PubMed

Jiang, Kuosheng; Xu, Guanghua; Liang, Lin; Tao, Tangfei; Gu, Fengshou

2014-07-29

In this paper a stochastic resonance (SR)-based method for recovering weak impulsive signals is developed for quantitative diagnosis of faults in rotating machinery. It was shown in theory that weak impulsive signals follow the mechanism of SR, but the SR produces a nonlinear distortion of the shape of the impulsive signal. To eliminate the distortion a moving least squares fitting method is introduced to reconstruct the signal from the output of the SR process. This proposed method is verified by comparing its detection results with that of a morphological filter based on both simulated and experimental signals. The experimental results show that the background noise is suppressed effectively and the key features of impulsive signals are reconstructed with a good degree of accuracy, which leads to an accurate diagnosis of faults in roller bearings in a run-to failure test.

An improved model for provision of rural community-based health rehabilitation services in Vhembe District, Limpopo Province of South Africa

PubMed Central

Netshandama, Vhonani O.; Francis, Joseph

2016-01-01

Background In 1991, Riakona Community Rehabilitation Programme initiated community-based rehabilitation (CBR) in the Vhembe District of Limpopo Province. Subsequently, the South African government adopted the programme. Aim The aim of the study was to suggest an improvement in the model of providing CBR services. Setting The study was conducted in six rehabilitation centres located in hospitals in the Vhembe District in Limpopo Province of South Africa. Method A mixed-mode research design with qualitative and quantitative elements was used to conduct the study. Content analysis, the chi-square test for Goodness of Fit and the Kruskal–Wallis and Mann–Whitney non-parametric tests were conducted. Results The key determinants of client satisfaction with the services that the community rehabilitation workers rendered included provision of assistive devices and the adoption of a holistic approach to their work. Overall, satisfaction per domain for each one of the five domains of satisfaction scored less than 90%. More than 80% of clients were satisfied with empathy (83%) and assurance (80%) domains. Tangibles, reliability and responsiveness domains had scores of 78%, 72% and 67%, respectively. These results, together with the reasoning map of conceptual framework description, were used as the building blocks of the CBR model. Conclusion The improved CBR model is useful for putting the programme into practice. This is particularly so for the CBR managers in the districts of the Limpopo Province. PMID:27380835

Factors Influencing Consumer Purchase Decisions for Health-Promoting Goods and Services in Malaysia

PubMed Central

CHEAH, Yong Kang

2014-01-01

Background: In the context of global increases in the prevalence of non-communicable diseases, the objective of the present study is to investigate the factors affecting individuals’ decisions to use health-promoting goods and services. Methods: The Third National Health and Morbidity Survey (NHMS III), consisting of 30992 respondents, was analysed. The Pearson chi-square test was applied to compare the distribution of categorical variables. A binary logistic regression model was used to assess the likelihood of using health-promoting goods and services. Results: Age, income, gender, ethnicity, education, marital status, location of residence, job characteristics, and being diagnosed with hypercholesterolemia were significantly associated with use of health-promoting goods and services. In contrast, young individuals, low income earners, males, Indians and others, the less-educated, single individuals, rural dwellers, the unemployed and individuals with hypercholesterolemia were less likely to use health-promoting goods and services than others. Conclusion: Socio-demographic and health factors played an important role in affecting the use of health-promoting goods and services. Based on these factors, several intervention measures with the intent of increasing the use of health-promoting goods and services were suggested, if only applicable to Malaysians. PMID:25897281

Performance assessment of individual and ensemble data-mining techniques for gully erosion modeling.

PubMed

Pourghasemi, Hamid Reza; Yousefi, Saleh; Kornejady, Aiding; Cerdà, Artemi

2017-12-31

Gully erosion is identified as an important sediment source in a range of environments and plays a conclusive role in redistribution of eroded soils on a slope. Hence, addressing spatial occurrence pattern of this phenomenon is very important. Different ensemble models and their single counterparts, mostly data mining methods, have been used for gully erosion susceptibility mapping; however, their calibration and validation procedures need to be thoroughly addressed. The current study presents a series of individual and ensemble data mining methods including artificial neural network (ANN), support vector machine (SVM), maximum entropy (ME), ANN-SVM, ANN-ME, and SVM-ME to map gully erosion susceptibility in Aghemam watershed, Iran. To this aim, a gully inventory map along with sixteen gully conditioning factors was used. A 70:30% randomly partitioned sets were used to assess goodness-of-fit and prediction power of the models. The robustness, as the stability of models' performance in response to changes in the dataset, was assessed through three training/test replicates. As a result, conducted preliminary statistical tests showed that ANN has the highest concordance and spatial differentiation with a chi-square value of 36,656 at 95% confidence level, while the ME appeared to have the lowest concordance (1772). The ME model showed an impractical result where 45% of the study area was introduced as highly susceptible to gullying, in contrast, ANN-SVM indicated a practical result with focusing only on 34% of the study area. Through all three replicates, the ANN-SVM ensemble showed the highest goodness-of-fit and predictive power with a respective values of 0.897 (area under the success rate curve) and 0.879 (area under the prediction rate curve), on average, and correspondingly the highest robustness. This attests the important role of ensemble modeling in congruently building accurate and generalized models which emphasizes the necessity to examine different models integrations. The result of this study can prepare an outline for further biophysical designs on gullies scattered in the study area. Copyright © 2017 Elsevier B.V. All rights reserved.

Qualitative and quantitative salivary changes and subjective oral dryness among patients with thyroid dysfunction.

PubMed

Naik, Meghal Mehul; Vassandacoumara, Vaishnavee

2018-01-01

There is a paucity of literature regarding the effects of thyroid disorders on the oral cavity by influencing the salivary gland function. This study aims to understand the qualitative and quantitative changes that thyroid disorder can cause in the salivary function. After obtaining ethical clearance, 46 consecutive newly diagnosed thyroid dysfunction patients were enrolled in this cross-sectional study, along with 45 age-and sex-matched controls. Unstimulated and stimulated salivary flow rates, pH, and buffering capacity of the whole saliva were studied in addition to subjective oral dryness in the study participants. The independent t-test was employed to compare the means between the two groups and Pearson's Chi-square test was used to assess the goodness of fit. The findings showed that females are more affected with thyroid disorders and that hypothyroidism is more commonly reported than hyperthyroidism. A significant reduction in the salivary flow rates and buffering capacity was observed among the affected group compared to the controls, whereas the salivary pH did not show significant differences between genders and also between the case and control groups. A feeling of subjective oral dryness was perceived by many affected patients. The study was able to establish an association between thyroid dysfunction and salivary gland function. We hope that this study leads to more high-impact research in this field as salivary diagnostics is gaining more popularity with every passing day.

Simulation of Autonomic Logistics System (ALS) Sortie Generation

DTIC Science & Technology

2003-03-01

84 Appendix B. ANOVA Assumptions Mission Capable Rate ANOVA Assumptions Constant Variance SSR # X cols SSE n Breusch - Pagan Chi-square 3.57E...85 Flying Scheduling Effectiveness ANOVA Assumptions Constant Variance SSR # X cols SSE n Breusch - Pagan Chi-square 2.12E-10 3 0.000816 270...Constant Variance SSR # X cols SSE n Breusch - Pagan Chi-square 1.86E-09 3 0.003758 270 3.20308814 0.9556957 Independence Durbin-Watson

Socioeconomic and Health Profile of Haitian Immigrants in a Brazilian Amazon State.

PubMed

Borges, Fabiano Tonaco; Muraro, Ana Paula; da Costa Leão, Luís Henrique; de Andrade Carvalho, Luciana; Siqueira, Carlos Eduardo Gomes

2018-01-25

We analyzed the sociodemographic profile, migration journey, health conditions, and health care access and utilization among recent Haitian immigrants to the Brazilian Amazon state of Mato Grosso. We conducted a cross-sectional study with a probabilistic sample of 452 Haitians. We administered a bilingual questionnaire from December 2014 to February 2015. Data were analyzed using chi square tests to evaluate differences among groups. The majority of participants were married men younger than 35 years old. They mostly came from the Haiti's Artibonite Department, living in Brazil for less than a year. Half of the participants were employed at the time of the interviews, and 81.8% relied exclusively on the Brazilian Unified Healthcare System for medical care. The overall health profile and health care access were good. Haitian migration to Brasil is a case of South-South migration driven by economic needs. Our population had good health status despite socioeconomic challenges.

From least squares to multilevel modeling: A graphical introduction to Bayesian inference

NASA Astrophysics Data System (ADS)

Loredo, Thomas J.

2016-01-01

This tutorial presentation will introduce some of the key ideas and techniques involved in applying Bayesian methods to problems in astrostatistics. The focus will be on the big picture: understanding the foundations (interpreting probability, Bayes's theorem, the law of total probability and marginalization), making connections to traditional methods (propagation of errors, least squares, chi-squared, maximum likelihood, Monte Carlo simulation), and highlighting problems where a Bayesian approach can be particularly powerful (Poisson processes, density estimation and curve fitting with measurement error). The "graphical" component of the title reflects an emphasis on pictorial representations of some of the math, but also on the use of graphical models (multilevel or hierarchical models) for analyzing complex data. Code for some examples from the talk will be available to participants, in Python and in the Stan probabilistic programming language.

Evidence of Syndemics and Sexuality-Related Discrimination Among Young Sexual-Minority Women

PubMed Central

Kinsky, Suzanne M.; Herrick, Amy L.; Stall, Ron D.; Bauermeister, José A.

2015-01-01

Abstract Purpose: Syndemics, or the co-occurrence and interaction of health problems, have been examined extensively among young men who have sex with men, but their existence remain unexamined, to our knowledge, among sexual-minority (i.e., lesbian, gay, and bisexual) women. Thus, we investigated if syndemics were present among young sexual-minority women, and if sexual-orientation discrimination was an independent variable of syndemic production. Methods: A total of 467 sexual-minority women between the ages of 18 and 24 completed a cross-sectional online survey regarding their substance use, mental health, sexual behaviors, height, weight, and experiences of discrimination. We used structural equation modeling to investigate the presence of syndemics and their relationship to sexual-orientation discrimination. Results: Heavy episodic drinking, marijuana use, ecstasy use, hallucinogen use, depressive symptoms, multiple sexual partners, and history of sexually transmitted infections (STIs) comprised syndemics in this population (chi-square=24.989, P=.201; comparative fit index [CFI]=0.946; root mean square error of approximation [RMSEA]=0.023). Sexual-orientation discrimination is significantly and positively associated with the latent syndemic variable (unstandardized coefficient=0.095, P<.05), and this model fit the data well (chi-square=33.558, P=.059; CFI=0.914; RMSEA=0.029). The reverse causal model showed syndemics is not an independent variable of sexual-orientation discrimination (unstandardized coefficient=0.602, P>.05). Conclusions: Syndemics appear to be present and associated with sexual-orientation discrimination among young sexual-minority women. Interventions aimed at reducing discrimination or increasing healthy coping may help reduce substance use, depressive symptoms, and sexual risk behaviors in this population. PMID:26788674

The Mentoring Competency Assessment: Validation of a New Instrument to Evaluate Skills of Research Mentors

PubMed Central

Fleming, Michael; House, Stephanie; Shewakramani, Vansa; Yu, Lan; Garbutt, Jane; McGee, Richard; Kroenke, Kurt; Abedin, Zainab; Rubio, Doris M.

2013-01-01

Purpose To determine the psychometric properties of the Mentoring Competency Assessment (MCA), a 26-item skills inventory that enables research mentors and mentees to evaluate six competencies of mentors: maintaining effective communication, aligning expectations, assessing understanding, addressing diversity, and fostering independence promoting professional development. Method In 2010, investigators administered the MCA to 283 mentor–mentee pairs from 16 universities participating in a trial of a mentoring curriculum for clinical and translational research mentors. The authors analyzed baseline MCA data to describe the instrument’s psychometric properties. Results Coefficient alpha scores for the MCA showed reliability (internal consistency). The hypothesized model with its six latent constructs (competencies) resulted in an acceptable fit to the data. For the instrument completed by mentors, chi-square = 663.20; df = 284; P < .001; root mean square error of approximation (RMSEA) = 0.069 (90% CI, 0.062–0.076); confirmatory fit index (CFI) = 0.85; and Tucker-Lewis index (TLI) = 0.83. For the instrument completed by mentees, chi-square = 840.62; df = 284; P < .001; RMSEA = 0.080 (90% CI, 0.063–0.077); CFI = 0.87; and TLI = 0.85. The correlations among the six competencies were high: 0.49–0.87 for mentors, 0.58–0.92 for mentees. All parameter estimates for the individual items were significant; standardized factor loadings ranged from 0.32–0.81 for mentors and 0.56–0.86 for mentees. Conclusions The findings demonstrate that the MCA has reliability and validity. In addition, this study provides preliminary norms derived from a national sample of mentors and mentees. PMID:23702534

Clinical statistics analysis on the characteristics of pneumoconiosis of Chinese miner population

PubMed Central

Wang, Mei-Fang; Li, Run-Ze; Li, Ying; Cheng, Xue-Qin; Yang, Jun; Chen, Wen; Fan, Xing-Xing; Pan, Hu-Dan; Yao, Xiao-Jun; Ren, Tao; Qian, Xin

2016-01-01

Background Pneumoconiosis is one of the most common occupational diseases, which shows the progressive and irreversible pathological changes. It ultimately can induce pulmonary failure and lead to death. To date, these patients have no curative treatment option under the current standard of care, so it is especially important to delay the onset of the disease and slow down its progression. Therefore, understanding of clinical features of pneumoconiosis is particularly critical for medical intervention. Methods We collected the clinical data from 118 pneumoconiosis cases of miners admitted in hospital and processed the statistics analysis by using the Chi-square test and the risk assessment. Results Compared to other types of miners, gold miners are liable to cause Broncho-pulmonary co-infection with Chi-square value 18.748 and the P value <0.001. However, unexpectedly, the smoking miners displayed a better Activities of Daily Living (ADLs) compared to non-smokers, which showed 19.318 of Chi-square score and less than 0.001 of P value. And this connection was associated with the dust exposure time (P<0.05), showing the increasing risk of non-smoking miners occurred as the increasing time exposed to dust. In addition, our analysis indicated that the probability of smoking miners suffered from Broncho-pulmonary co-infection was less than non-smoking miners with Chi-square value 8.044 and P<0.01, which was also associated with the dust exposure time tendentiously, though P>0.05. Moreover, smoking history exhibited a deteriorating effect to the overall survival (OS) with 9.546 of Chi-square value and P<0.05, in accordance with smoking reducing life time. Interestingly, pneumoconiosis drugs could extend the smokers’ OS, but not non-smokers’. Conclusions Our studies suggest that the history of smoking and exposure time of dust play important roles in the development of pneumoconiosis and smoking could be a factor that determines the treatment options depending on patients’ smoking history. PMID:27621877

Specular reflectance of optical-black coatings in the far infrared

NASA Technical Reports Server (NTRS)

Smith, S. M.

1984-01-01

Far-infrared specular reflectance spectra of seven optically black coatings near normal incidence are presented. Seven photometric spectra were obtained using eleven bandpass transmission filters in the wavelength range between 12 and 500 microns, and three interferometric spectra were obtained for corroboration. Data on the construction, thickness, and rms surface roughness of the coatings are also presented. The chemical composition of three coatings can be distinguished from that of the others by a strong absorption feature between 20 and 40 microns, which can be largely attributed to amorphous silicate material. At 100 microns, the most and least reflective coatings differ by nearly 3 orders of magnitude. Inverse relationships observed between the spectra and the roughness and thickness of the coatings led to development of a reflecting-layer model for the measured reflectance. The model successfully describes the spectra at wavelengths outside the silicate absorption, and optical constants are deduced from a nonlinear least squares fit to the data. Parametric errors are estimated by chi-square analysis, and sensitivity tests are performed to determine which parameters control reflectance in different spectral regions.

Personal hygiene among military personnel: developing and testing a self-administered scale.

PubMed

Saffari, Mohsen; Koenig, Harold G; Pakpour, Amir H; Sanaeinasab, Hormoz; Jahan, Hojat Rshidi; Sehlo, Mohammad Gamal

2014-03-01

Good personal hygiene (PH) behavior is recommended to prevent contagious diseases, and members of military forces may be at high risk for contracting contagious diseases. The aim of this study was to develop and test a new questionnaire on PH for soldiers. Participants were all male and from different military settings throughout Iran. Using a five-stage guideline, a panel of experts in the Persian language (Farsi) developed a 21-item self-administered questionnaire. Face and content validity of the first-draft items were assessed. The questionnaire was then translated and subsequently back-translated into English, and both the Farsi and English versions were tested in pilot studies. The consistency and stability of the questionnaire were tested using Cronbach's alpha and the test-retest strategy. The final scale was administered to a sample of 502 military personnel. Explanatory and confirmatory factor analyses evaluated the structure of the scale. Both the convergent and discriminative validity of the scale were also determined. Cronbach's alpha coefficients were >0.85. Principal component analysis demonstrated a uni-dimensional structure that explained 59 % of the variance in PH behaviors. Confirmatory factor analysis indicated a good fit (goodness-of-fit index = 0.902; comparative fitness index = 0.923; root mean square error of approximation = 0.0085). The results show that this new PH scale has solid psychometric properties for testing PH behaviors among an Iranian sample of military personnel. We conclude that this scale can be a useful tool for assessing PH behaviors in military personnel. Further research is needed to determine the scale's value in other countries and cultures.

Consumer motivations toward buying local rice: The case of northern Iranian consumers.

PubMed

Rahnama, Hassan

2017-07-01

This research had two purposes. The first aim was to identify Iranian and Non-Iranian rice consumers based on demographic characteristics and examine difference of these features with buying behaviors. The second purpose of study was to investigate consumer's motivation to buy local rice in Iran. The sample were 1500 people (men and women). The data was collected by using questionnaire based on a face-to-face survey. Chi-square, confirmatory factor analysis, and multiple linear regression were applied to assess collected data by a questionnaire survey. Regarding Iranian local rice buyers, 884 people buy local rice. Chi-square test showed that there is a significant difference between gender, having children, and marital status in buying local rice. Habitual Iranian local rice buyers include: female (51%), people who are more than 45 years old (51%), people with children (63%), people who are living urban (61%), married people (48%) and individuals that their monthly income is between 321.5 and 625 Dollars (53%). Regarding non-Iranian rice buyers, 616 people buy it. Also there is a significant difference between gender, location, marital status, and income in buying local rice. For considering consumers motivation toward buying local rice the econometrical model is used. Model had three aspects including; quality aspects (taste, good appearance), economic aspects (price, convenience, consumer's ethnocentrism), and safety aspects (health, not using pesticides and environment protection) and seven subset. The results of analysis indicated that quality aspects, economic aspects and safety aspects have positive effects on buying Iranian local rice. Also, indicative variables including; taste, good appearance, price, convenience, consumer's ethnocentrism, health, not using pesticides and environment have significant effects on buying it. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physical Activity and Fitness of First Nations Youth in a Remote and Isolated Northern Ontario Community: A Needs Assessment.

PubMed

Gates, Michelle; Hanning, Rhona; Gates, Allison; Stephen, Judy; Fehst, Andrew; Tsuji, Leonard

2016-02-01

Among a group of First Nations youth, this research aimed to obtain objective measures of anthropometry, physical activity (PA) and fitness; to identify any group-level differences by sex, body mass index, waist circumference and body fat categories; to assess the barriers and supports to PA. Youth participated in anthropometric measures (BMI, waist circumference, body fat percentage), PA assessment (3 days of accelerometry) and fitness testing (guided by the Canadian Physical Activity, Fitness and Lifestyle Approach). Barriers and supports were assessed via environmental scan and focus groups. Descriptive statistics were compared to reference data. Group differences by sex, BMI status, waist circumference and body fat categories were tested using Mann-Whitney U and Chi square tests (p ≤ 0.05). Qualitative data were assembled into one file and coded manually for categories and themes. Seventy-two youth (12.1 ± 1.1 years, 61.1% male) participated in at least one measure; 36 completed the accelerometry. Sixty-three percent were overweight or obese, 51% were abdominally obese and 21% had excess body fat. Most (86.1%) met Canada's PA guidelines. Boys were more active than girls (p = 0.025) and had greater cardiorespiratory endurance (p = 0.003). Overweight, obese, or abdominally obese youth had lower cardiorespiratory endurance than normal weight youth (p < 0.001). Barriers and supports fell under the main themes: motivation, role models, personnel and facilities, environment and programs. Based on this assessment, youth in this community are active, but not sufficiently physically fit, especially among those affected by obesity and abdominal obesity. The findings, in addition to the numerous barriers to PA, support the community's desire for school-based PA programming.

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

Hou Fengji; Hogg, David W.; Goodman, Jonathan

Markov chain Monte Carlo (MCMC) proves to be powerful for Bayesian inference and in particular for exoplanet radial velocity fitting because MCMC provides more statistical information and makes better use of data than common approaches like chi-square fitting. However, the nonlinear density functions encountered in these problems can make MCMC time-consuming. In this paper, we apply an ensemble sampler respecting affine invariance to orbital parameter extraction from radial velocity data. This new sampler has only one free parameter, and does not require much tuning for good performance, which is important for automatization. The autocorrelation time of this sampler is approximatelymore » the same for all parameters and far smaller than Metropolis-Hastings, which means it requires many fewer function calls to produce the same number of independent samples. The affine-invariant sampler speeds up MCMC by hundreds of times compared with Metropolis-Hastings in the same computing situation. This novel sampler would be ideal for projects involving large data sets such as statistical investigations of planet distribution. The biggest obstacle to ensemble samplers is the existence of multiple local optima; we present a clustering technique to deal with local optima by clustering based on the likelihood of the walkers in the ensemble. We demonstrate the effectiveness of the sampler on real radial velocity data.« less

Synchrotron speciation data for zero-valent iron nanoparticles

EPA Pesticide Factsheets

This data set encompasses a complete analysis of synchrotron speciation data for 5 iron nanoparticle samples (P1, P2, P3, S1, S2, and metallic iron) to include linear combination fitting results (Table 6 and Figure 9) and ab-initio extended x-ray absorption fine structure spectroscopy fitting (Figure 10 and Table 7).Table 6: Linear combination fitting of the XAS data for the 5 commercial nZVI/ZVI products tested. Species proportions are presented as percentages. Goodness of fit is indicated by the chi^2 value.Figure 9: Normalised Fe K-edge k3-weighted EXAFS of the 5 commercial nZVI/ZVIproducts tested. Dotted lines show the best 4-component linear combination fit ofreference spectra.Figure 10: Fourier transformed radial distribution functions (RDFs) of the five samplesand an iron metal foil. The black lines in Fig. 10 represent the sample data and the reddotted curves represent the non-linear fitting results of the EXAFS data.Table 7: Coordination parameters of Fe in the samples.This dataset is associated with the following publication:Chekli, L., B. Bayatsarmadi, R. Sekine, B. Sarkar, A. Maoz Shen, K. Scheckel , W. Skinner, R. Naidu, H. Shon, E. Lombi, and E. Donner. Analytical Characterisation of Nanoscale Zero-Valent Iron: A Methodological Review. Richard P. Baldwin ANALYTICA CHIMICA ACTA. Elsevier Science Ltd, New York, NY, USA, 903: 13-35, (2016).

Filter Tuning Using the Chi-Squared Statistic

NASA Technical Reports Server (NTRS)

Lilly-Salkowski, Tyler B.

2017-01-01

This paper examines the use of the Chi-square statistic as a means of evaluating filter performance. The goal of the process is to characterize the filter performance in the metric of covariance realism. The Chi-squared statistic is the value calculated to determine the realism of a covariance based on the prediction accuracy and the covariance values at a given point in time. Once calculated, it is the distribution of this statistic that provides insight on the accuracy of the covariance. The process of tuning an Extended Kalman Filter (EKF) for Aqua and Aura support is described, including examination of the measurement errors of available observation types, and methods of dealing with potentially volatile atmospheric drag modeling. Predictive accuracy and the distribution of the Chi-squared statistic, calculated from EKF solutions, are assessed.

[Comparison of thromboelastography and routine coagulation tests for evaluation of blood coagulation function in patients].

PubMed

Chen, Guan-Yi; Ou Yang, Xi-Lin; Wu, Jing-Hui; Wang, Li-Hua; Yang, Jin-Hua; Gu, Li-Nan; Lu, Zhu-Jie; Zhao, Xiao-Zi

2015-04-01

To investigate the correlation and consistency between thromboelastography(TEG) and routine coagulation tests, and to evaluate the value of the two methods in determining the blood coagulation of patients. The TEG, routine coagulation tests and platelet counts of 182 patients from the Intensive Care Unit(ICU) and Department of Gastroenterology in our hospital from January to September 2014 were performed and analyzed retrospectively for their correlation, Kappa identity test analysis and chi-square test, and the diagnostic sensitivity and specificity of both methods in the patients with bleeding were evaluated. The TEG R time and PT, R time and APTT showed a linear dependence (P<0.01). The relationship between the TEG K value, α-Angle, MA and Fibrinogen showed a linear dependence (P<0.001). And the relationship between the TEG K value, α-Angle, MA and the platelet count were in a linear dependent way (P<0.001). The Kappa values of the TEG R time with PT and APTT were 0.038 (P>0.05) and 0.061 (P>0.05), respectively. The chi-square test values of the TEG R time with PT and APTT were 35.309 (P<0.001) and 15.848 (P<0.001), respectively. The Fibrinogen and the TEG K value, α-Angle, MA value had statistical significance (P<0.001), with a Kappa value of 0.323, 0.288 and 0.427, respectively. The chi-square test values between Fibrinogen and the TEG K value, α-Angle, MA value were not statistically significant, with X2=1.091 (P=0.296), X2=1.361 (P=0.243), X2=0.108 (P=0.742). The Kappa values of the platelet count and the TEG K value, α-Angle, MA value were 0.379, 0.208 and 0.352, respectively, which were also statistically significant difference (P<0.001). The chi-square test values between the platelet count and the TEG K value, α-Angle, MA value showed a statistically significant difference (P<0.001), with X2=37.5, X2=37.23, X2=26.630. The diagnostic sensitivity of the two methods for the patients with bleeding was less than 50%. There was a significant correlation between some TEG parameters and routine coagulation tests, but the consistency is weak. Moreover, the diagnostic sensitivity of two methods in the patients with bleeding is low. It was concluded that the TEG cannot replace the conventional coagulation tests, and the preferable method remains uncertain which could reflect the risk of bleeding.

Measuring Skew in Average Surface Roughness as a Function of Surface Preparation

NASA Technical Reports Server (NTRS)

Stahl, Mark T.

2015-01-01

Characterizing surface roughness is important for predicting optical performance. Better measurement of surface roughness reduces grinding saving both time and money and allows the science requirements to be better defined. In this study various materials are polished from a fine grind to a fine polish. Each sample's RMS surface roughness is measured at 81 locations in a 9x9 square grid using a Zygo white light interferometer at regular intervals during the polishing process. Each data set is fit with various standard distributions and tested for goodness of fit. We show that the skew in the RMS data changes as a function of polishing time.

Open versus laparoscopic approach in the treatment of abdominal emergencies in elderly population

PubMed Central

COCORULLO, G.; FALCO, N.; TUTINO, R.; FONTANA, T.; SCERRINO, G.; SALAMONE, G.; LICARI, L.; GULOTTA, G.

2016-01-01

Aim To evaluate the role of laparoscopy in the treatment of surgical emergency in old population. Patients and Methods Over-70 years-old patients submitted to emergency abdominal surgery from January 2013 to December 2014 were collected and grouped according to admission diagnoses. These accounted small bowel obstruction, colonic acute disease, appendicitis, ventral hernia, gastro-duodenal perforation, biliary disease. In each group it was analyzed the operation time (OT), the morbidity rate and the mortality rate comparing open and laparoscopic management using T-test and Chi-square test. Results 159 over 70-years-old patients underwent emergency surgery in the General and Emergency surgery Operative Unit (O.U.) of the Policlinic of Palermo. 75 patients were managed by a laparoscopic approach and 84 underwent traditional open emergency surgery. T-Test for OT and Chi-square test for morbidity rate and mortality rate showed no differences in small bowel emergencies (p=0,4; 0,250,9; p>0,95) and in gastro-duodenal perforation (p=0,9; p>0.9; p>0.95). In cholecystitis, laparoscopy group showed lower OT (T-Test: p= 0,0002) while Chi-square test for morbidity rate (0,1

Depression, stress, and intimate partner violence among Latino migrant and seasonal farmworkers in rural Southeastern North Carolina.

PubMed

Kim-Godwin, Yeoun Soo; Maume, Michael O; Fox, Jane A

2014-12-01

The purpose of the study is to identify the predictors of depression and intimate partner violence (IPV) among Latinos in rural Southeastern North Carolina. A sample of 291 migrant and seasonal farmworkers was interviewed to complete the demographic questionnaire, HITS (intimate violence tendency), Migrant Farmworker Stress Inventory, Center for Epidemiologic Studies Depression Scale (depression), and CAGE/4M (alcohol abuse). OLS regression and structural equation modeling were used to test the hypothesized relations between predictors of IPV and depression. The findings indicated that respondents reporting higher levels of stress also reported higher levels of IPV and depression. The goodness-of-fit statistics for the overall model again indicated a moderate fit of the model to the data (χ2 = 5,612, p < .001; root mean square error for approximation = 0.09; adjusted goodness-of-fit index = 0.44; comparative fit index = 0.52). Although the findings were not robust to estimation in the structural equation models, the OLS regression models indicated direct associations between IPV and depression.

Environmental justice assessment for transportation : risk analysis

DOT National Transportation Integrated Search

1999-04-01

This paper presents methods of comparing populations and their racial/ethnic compositions using tabulations, histograms, and Chi Squared tests for statistical significance of differences found. Two examples of these methods are presented: comparison ...

Assessing Goodness of Fit in Item Response Theory with Nonparametric Models: A Comparison of Posterior Probabilities and Kernel-Smoothing Approaches

ERIC Educational Resources Information Center

Sueiro, Manuel J.; Abad, Francisco J.

2011-01-01

The distance between nonparametric and parametric item characteristic curves has been proposed as an index of goodness of fit in item response theory in the form of a root integrated squared error index. This article proposes to use the posterior distribution of the latent trait as the nonparametric model and compares the performance of an index…

Validation of the Hong Kong Liver Cancer Staging System in Determining Prognosis of the North American Patients Following Intra-arterial Therapy.

PubMed

Sohn, Jae Ho; Duran, Rafael; Zhao, Yan; Fleckenstein, Florian; Chapiro, Julius; Sahu, Sonia; Schernthaner, Rüdiger E; Qian, Tianchen; Lee, Howard; Zhao, Li; Hamilton, James; Frangakis, Constantine; Lin, MingDe; Salem, Riad; Geschwind, Jean-Francois

2017-05-01

There is debate over the best way to stage hepatocellular carcinoma (HCC). We attempted to validate the prognostic and clinical utility of the recently developed Hong Kong Liver Cancer (HKLC) staging system, a hepatitis B-based model, and compared data with that from the Barcelona Clinic Liver Cancer (BCLC) staging system in a North American population that underwent intra-arterial therapy (IAT). We performed a retrospective analysis of data from 1009 patients with HCC who underwent IAT from 2000 through 2014. Most patients had hepatitis C or unresectable tumors; all patients underwent IAT, with or without resection, transplantation, and/or systemic chemotherapy. We calculated HCC stage for each patient using 5-stage HKLC (HKLC-5) and 9-stage HKLC (HKLC-9) system classifications, and the BCLC system. Survival information was collected up until the end of 2014 at which point living or unconfirmed patients were censored. We compared performance of the BCLC, HKLC-5, and HKLC-9 systems in predicting patient outcomes using Kaplan-Meier estimates, calibration plots, C statistic, Akaike information criterion, and the likelihood ratio test. Median overall survival time, calculated from first IAT until date of death or censorship, for the entire cohort (all stages) was 9.8 months. The BCLC and HKLC staging systems predicted patient survival times with significance (P < .001). HKLC-5 and HKLC-9 each demonstrated good calibration. The HKLC-5 system outperformed the BCLC system in predicting patient survival times (HKLC C = 0.71, Akaike information criterion = 6242; BCLC C = 0.64, Akaike information criterion = 6320), reducing error in predicting survival time (HKLC reduced error by 14%, BCLC reduced error by 12%), and homogeneity (HKLC chi-square = 201, P < .001; BCLC chi-square = 119, P < .001) and monotonicity (HKLC linear trend chi-square = 193, P < .001; BCLC linear trend chi-square = 111, P < .001). Small proportions of patients with HCC of stages IV or V, according to the HKLC system, survived for 6 months and 4 months, respectively. In a retrospective analysis of patients who underwent IAT for unresectable HCC, we found the HKLC-5 staging system to have the best combination of performances in survival separation, calibration, and discrimination; it consistently outperformed the BCLC system in predicting survival times of patients. The HKLC system identified patients with HCC of stages IV and V who are unlikely to benefit from IAT. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

A Monte Carlo Approach to Unidimensionality Testing in Polytomous Rasch Models

ERIC Educational Resources Information Center

Christensen, Karl Bang; Kreiner, Svend

2007-01-01

Many statistical tests are designed to test the different assumptions of the Rasch model, but only few are directed at detecting multidimensionality. The Martin-Lof test is an attractive approach, the disadvantage being that its null distribution deviates strongly from the asymptotic chi-square distribution for most realistic sample sizes. A Monte…

A single factor underlies the metabolic syndrome: a confirmatory factor analysis.

PubMed

Pladevall, Manel; Singal, Bonita; Williams, L Keoki; Brotons, Carlos; Guyer, Heidi; Sadurni, Josep; Falces, Carles; Serrano-Rios, Manuel; Gabriel, Rafael; Shaw, Jonathan E; Zimmet, Paul Z; Haffner, Steven

2006-01-01

Confirmatory factor analysis (CFA) was used to test the hypothesis that the components of the metabolic syndrome are manifestations of a single common factor. Three different datasets were used to test and validate the model. The Spanish and Mauritian studies included 207 men and 203 women and 1,411 men and 1,650 women, respectively. A third analytical dataset including 847 men was obtained from a previously published CFA of a U.S. population. The one-factor model included the metabolic syndrome core components (central obesity, insulin resistance, blood pressure, and lipid measurements). We also tested an expanded one-factor model that included uric acid and leptin levels. Finally, we used CFA to compare the goodness of fit of one-factor models with the fit of two previously published four-factor models. The simplest one-factor model showed the best goodness-of-fit indexes (comparative fit index 1, root mean-square error of approximation 0.00). Comparisons of one-factor with four-factor models in the three datasets favored the one-factor model structure. The selection of variables to represent the different metabolic syndrome components and model specification explained why previous exploratory and confirmatory factor analysis, respectively, failed to identify a single factor for the metabolic syndrome. These analyses support the current clinical definition of the metabolic syndrome, as well as the existence of a single factor that links all of the core components.

Latent class profile of psychiatric symptoms and treatment utilization in a sample of patients with co-occurring disorders.

PubMed

Villalobos-Gallegos, Luis; Marín-Navarrete, Rodrigo; Roncero, Calos; González-Cantú, Hugo

2017-01-01

To identify symptom-based subgroups within a sample of patients with co-occurring disorders (CODs) and to analyze intersubgroup differences in mental health services utilization. Two hundred and fifteen patients with COD from an addiction clinic completed the Symptom Checklist 90-Revised. Subgroups were determined using latent class profile analysis. Services utilization data were collected from electronic records during a 3-year span. The five-class model obtained the best fit (Bayesian information criteria [BIC] = 3,546.95; adjusted BIC = 3,363.14; bootstrapped likelihood ratio test p < 0.0001). Differences between classes were quantitative, and groups were labeled according to severity: mild (26%), mild-moderate (28.8%), moderate (18.6%), moderate-severe (17.2%), and severe (9.3%). A significant time by class interaction was obtained (chi-square [χ2[15

The organization of irrational beliefs in posttraumatic stress symptomology: testing the predictions of REBT theory using structural equation modelling.

PubMed

Hyland, Philip; Shevlin, Mark; Adamson, Gary; Boduszek, Daniel

2014-01-01

This study directly tests a central prediction of rational emotive behaviour therapy (REBT) that has received little empirical attention regarding the core and intermediate beliefs in the development of posttraumatic stress symptoms. A theoretically consistent REBT model of posttraumatic stress disorder (PTSD) was examined using structural equation modelling techniques among a sample of 313 trauma-exposed military and law enforcement personnel. The REBT model of PTSD provided a good fit of the data, χ(2) = 599.173, df = 356, p < .001; standardized root mean square residual = .05 (confidence interval = .04-.05); standardized root mean square residual = .04; comparative fit index = .95; Tucker Lewis index = .95. Results demonstrated that demandingness beliefs indirectly affected the various symptom groups of PTSD through a set of secondary irrational beliefs that include catastrophizing, low frustration tolerance, and depreciation beliefs. Results were consistent with the predictions of REBT theory and provides strong empirical support that the cognitive variables described by REBT theory are critical cognitive constructs in the prediction of PTSD symptomology. © 2013 Wiley Periodicals, Inc.

The use of Cole-Cole plots to compare two multifrequency bioimpedance instruments.

PubMed

Stroud, D B; Cornish, B H; Thomas, B J; Ward, L C

1995-10-01

Two commercially available multifrequency bioimpedance spectrometers (Xitron 4000B and SEAC SFB3) were compared by performing measurements on a set of electronic circuits and by studying 14 healthy volunteers. Output data were plotted as reactance versus resistance and fitted with a semi-circle using a least squares fitting program. In tests with six electronic circuits both instruments produced impedance loci that were well described by semicircular Cole-Cole plots, though there were some minor discrepancies using the Xitron instrument at frequencies above 150 kHz. When tested on the volunteers the SEAC instrument gave very good fits (RMSE = 1.5 Omega) to a semi-circle from 5-600 kHz on all volunteers. The Xitron instrument gave excellent fits to the semi-circle between 5 and 55 kHz (RMSE = 0.7 Omega) but above 55 kHz the phase measurements stayed constant or even increased, confirming the anomalous behaviour reported by other authors. The conclusions to be drawn are that the semicircular plots predicted by the Cole-Cole theory give a very good description of multifrequency impedance data recorded by the SEAC SFB3 instrument, on human subjects, for frequencies between 5 and 600 kHz. The Xitron 4000B is not able to reproduce the theoretically expected results in humans above 55 kHz.

Influence of Field Position on Rugby League Players Requiring Shoulder Reconstruction.

PubMed

Bokor, D J; Sundaram, A; Graham, P L

2016-06-01

A consecutive series of patients sustaining their index anterior instability while playing Rugby League and requiring shoulder reconstruction was retrospectively reviewed and evaluated. The details of their on-field position and hand dominance at time of injury, the side of injury, and mechanism of injury were collated and statistically analyzed. A total of 173 Bankart repairs were performed on 132 patients, and 102 players had one injury while 30 had 2 or more injuries. Players are more likely to injure their non-dominant side (P=0.009) in the first-time injury. Whereas second and subsequent injuries were not associated with a particular side (P=0.81). Applying a Bonferroni correction to the chi-squared goodness-of-fit test of position at time of injury revealed players on the wing had a significantly lower frequency of injury (P<0.001), whereas the full back had a significantly higher frequency of injury (P<0.001). 30 players sustained 69 re-dislocations with the lock and fullback positions incurring significantly more re-injuries and the wing position fewer re-injuries than expected (P<0.006). Understanding which player positions on the rugby league field are more likely to sustain an anterior instability will assist medical and support staff to optimize the pre-season conditioning and post surgical rehabilitation of players. © Georg Thieme Verlag KG Stuttgart · New York.

Admixture analysis of the diagnostic subtypes of social anxiety disorder: implications for the DSM-V.

PubMed

Aderka, Idan M; Nickerson, Angela; Hofmann, Stefan G

2012-06-01

Much controversy exists regarding diagnostic subtypes of social anxiety disorder (SAD). The present study used admixture analysis to examine whether individuals with generalized and nongeneralized SAD belong to the same or different populations of origin. This can inform diagnostic subtyping of SAD in the forthcoming DSM-V. Treatment-seeking individuals with generalized SAD (n = 154) and nongeneralized SAD (n = 48) completed a battery of questionnaires. Based on participants' responses to the Liebowitz Social Anxiety Scale (LSAS), we estimated log likelihood and chi-square goodness-of-fit for models with 1, 2, 3, or 4 populations of origin, and compared models using forward stepwise estimation and maximum likelihood ratio tests. Admixture analyses suggested that the two diagnostic subtypes of SAD belong to the same underlying population of origin. In addition, observable differences in depression, general anxiety, and comorbidity were no longer significant when controlling for social anxiety severity. Our sample was recruited in the U.S. and was a treatment-seeking sample. Future studies should examine whether our results generalize to different cultures, and community samples. Support for qualitative differences between SAD subtypes was not found. Rather, our findings support the notion that the diagnostic subtypes of SAD differ quantitatively, and that SAD exists on a continuum of severity. This finding informs diagnostic subtyping of SAD in the forthcoming DSM-V. Copyright © 2011 Elsevier Ltd. All rights reserved.

Reported Influences on Restaurant-Type Food Selection Decision Making in a Grocery Store Chain.

PubMed

Bachman, Jessica Lynne; Arigo, Danielle

2018-06-01

To examine food decision-making priorities for restaurant-type foods at grocery stores and determine whether adding calorie information, as required by federal menu labeling laws, affected decision-making priorities. Natural experiment: intervention and control groups with baseline and follow-up. Regional grocery store chain with 9 locations. Participants (n = 393; mean age, 54.8 ± 15.1 years) were primarily women (71%) and Caucasian (95%). Data were collected before and after calorie information was added to restaurant-type foods at 4 intervention locations. Primary influencers of food selection decision making for restaurant-type foods and frequency of use of nutrition information. Quantitative analysis examined the top 3 influencers of food selections and chi-square goodness of fit test determined whether the calorie labeling intervention changed food decision-making priorities. Qualitative data were used to describe responses. Taste, cost, and convenience were the most frequently reported influencers of restaurant-type food selections; 20% of participants rated calories as influential. Calorie labeling did not affect food selection decision making; 16% of participants in intervention stores noticed calorie labels. Qualitative explanations confirmed these findings. Menu labeling laws increase access to calorie information; however, use of this information is limited. Additional interventions are needed to encourage healthier restaurant-type food selections in grocery stores. Copyright © 2018 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Pattern of Antibiotic Prescription among Dentists in Iran

PubMed Central

Kakoei, Shahla; Raoof, Maryam; Baghaei, Fahimeh; Adhami, Shahrzad

2007-01-01

INTRODUCTION: This study examines the antibiotic prescription in dentists participated in 9th Congress of Iranian Association of Endodontists in Esfahan/2006. MATERIALS AND METHODS: A questionnaire for this cross sectional study was designed for evaluating the patterns of antibiotic prescription. It included some demographic information, clinical signs, and conditions in need for antibiotic and prophylactic prescription and their choices. Data was analyzed using Pearson’s Chi-square test. RESULTS: High percentage of responders prescribe antibiotic for fever (78.2%) and diffuse swelling (85.1%). However, some situations such as acute pulpitis, chronic periapical lesions and marginal gingivitis were irrationally prescribed. CONCLUSION: This study showed a fairly good pattern of antibiotic prescription but it was far from ideal. PMID:24348653

Association between cardiorespiratory fitness and body fat in girls

PubMed Central

Minatto, Giseli; de Sousa, Thiago Ferreira; de Carvalho, Wellington Roberto Gomes; Ribeiro, Roberto Régis; Santos, Keila Donassolo; Petroski, Edio Luiz

2016-01-01

Abstract Objective: To estimate the prevalence of low cardiorespiratory fitness and its association with excess body fat, considering the sexual maturation and economic level in female adolescents. Methods: Cross-sectional, epidemiological study of 1223 adolescents (10-17 years) from the public school system of Cascavel, PR, Brazil, in 2006. We analyzed the self-assessed sexual maturation level (prepubertal, pubertal and post-pubertal), the economic level (high and low) through a questionnaire and body fat (normal and high) through triceps and subscapular skinfolds. The 20-meter back-and-forth test was applied to estimate maximum oxygen consumption. Cardiorespiratory fitness was assessed according to reference criteria and considered low when the minimum health criterion for age and sex was not met. Chi-square test and logistic regression were applied, with a significance level of 5%. Results: The prevalence of low cardiorespiratory fitness was 51.3%, being associated with all study variables (p<0.001). At the crude analysis, adolescents with high body fat were associated with low cardiorespiratory fitness, when compared to those with normal body fat (OR=2.76; 95%CI: 2.17-3.52). After adjustment by sexual maturation, this association remained valid and showed an effect that was 1.8-fold higher (95%CI: 1.39-2.46) and after adjusting by economic level, the effect was 1.9-fold higher (95%CI: 1.45-2.61). Conclusions: Approximately half of the assessed girls showed unsatisfactory levels of cardiorespiratory fitness for health, which was associated with high body fat, regardless of sexual maturation level and economic level. Effective public health measures are needed, with particular attention to high-risk groups. PMID:27131896

Association between cardiorespiratory fitness and body fat in girls.

PubMed

Minatto, Giseli; Sousa, Thiago Ferreira de; Carvalho, Wellington Roberto Gomes de; Ribeiro, Roberto Régis; Santos, Keila Donassolo; Petroski, Edio Luiz

2016-12-01

To estimate the prevalence of low cardiorespiratory fitness and its association with excess body fat, considering the sexual maturation and economic level in female adolescents. Cross-sectional, epidemiological study of 1,223 adolescents (10-17 years) from the public school system of Cascavel, PR, Brazil, in 2006. We analyzed the self-assessed sexual maturation level (prepubertal, pubertal and post-pubertal), the Economic Level (EL) (high and low) through a questionnaire and body fat (normal and high) through triceps and subscapular skinfolds. The 20-meter back-and-forth test was applied to estimate maximum oxygen consumption. Cardiorespiratory fitness was assessed according to reference criteria and considered low when the minimum health criterion for age and sex was not met. Chi-square test and logistic regression were applied, with a significance level of 5%. The prevalence of low cardiorespiratory fitness was 51.3%, being associated with all study variables (p<0.001). At the crude analysis, adolescents with high body fat were associated with low cardiorespiratory fitness, when compared to those with normal body fat (OR=2.76; 95%CI: 2.17-3.52). After adjustment by sexual maturation, this association remained valid and showed an effect that was 1.8-fold higher (95%CI: 1.39-2.46) and after adjusting by EL, the effect was 1.9-fold higher (95%CI: 1.45-2.61). Approximately half of the assessed girls showed unsatisfactory levels of cardiorespiratory fitness for health, which was associated with high body fat, regardless of sexual maturation level and EL. Effective public health measures are needed, with particular attention to high-risk groups. Copyright © 2016 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

Healthy life expectancy and the correlates of self-rated health in Bangladesh in 1996 and 2002.

PubMed

Tareque, Md Ismail; Saito, Yasuhiko; Kawahara, Kazuo

2015-03-31

Life expectancy (LE) at birth has increased steadily in Bangladesh since its independence. When people live longer, quality of life becomes a central issue. This study examines whether healthy life expectancy (HLE) at ages 15, 25, 35, and 45 is keeping pace with LE at those ages between 1996 and 2002. It also seeks to investigate the correlates of self-rated health (SRH) in 1996 and 2002. We used data from the World Values Survey conducted in 1996 and 2002 among individuals 15 years and older. The Sullivan method was used to compute HLE. Socio-demographic differences and their association with different states of health were examined by chi-square and Pearson's correlation tests. Multiple linear regression models were fitted to examine the correlates of SRH. The results show that perceived health improved between 1996 and 2002. For males, statistically significant increases in the expected number of years lived in good SRH were found. Proportionally, in 2002, both males and females at ages 15, 25, 35 and 45 expected more life years in good health and fewer life years in fair and poor health than did their counterparts in 1996. Comparatively, males expected fewer life years spent in good health but a much larger proportion of expected life in good health than did females. Finally, in multivariate analyses, life satisfaction was the only factor found to be significantly and positively associated with SRH for males and females in both years, although in both years the association was much more pronounced for females than for males. This study documented changes in HLE during 1996-2002. Women outlive men, but they have a lower quality of life and are more likely to live a greater part of their remaining life in poor SRH. Life satisfaction as well as other significant factors associated with SRH should be promoted, with special attention given to women, to improve healthy life expectancy and the quality of life of the Bangladeshi people.

Response Surface Analysis of Experiments with Random Blocks

DTIC Science & Technology

1988-09-01

partitioned into a lack of fit sum of squares, SSLOF, and a pure error sum of squares, SSPE . The latter is obtained by pooling the pure error sums of squares...from the blocks. Tests concerning the polynomial effects can then proceed using SSPE as the error term in the denominators of the F test statistics. 3.2...the center point in each of the three blocks is equal to SSPE = 2.0127 with 5 degrees of freedom. Hence, the lack of fit sum of squares is SSLoF

Polyomino Problems to Confuse Computers

ERIC Educational Resources Information Center

Coffin, Stewart

2009-01-01

Computers are very good at solving certain types combinatorial problems, such as fitting sets of polyomino pieces into square or rectangular trays of a given size. However, most puzzle-solving programs now in use assume orthogonal arrangements. When one departs from the usual square grid layout, complications arise. The author--using a computer,…

Exploring the seasonality of birth defects in the New York State Congenital Malformations Registry.

PubMed

Caton, Alissa R

2012-06-01

Examining seasonal patterns of birth defects may help to identify environmental risk factors. Because the teratogenic window for most birth defects is during gestational weeks 3 to 8, investigating exposures closer to the timing of conception is important. However, studies are usually based on month of birth, which is not the biologically relevant exposure period and does not account for differences in gestational length. We aimed to determine whether the occurrence of birth defects varied by month of conception using the population-based New York State Congenital Malformations Registry (CMR). We merged live birth certificates (n = 2,044,091) with CMR records for mothers residing in New York State, excluding New York City, for the years 1992 through 2006. We categorized birth defects according to the National Birth Defects Prevention Network guidelines and performed Cochran-Armitage trend, Hewitt-Rogerson, and Walter-Elwood tests on month of conception and chi-square tests on season of conception. We graphed seasonal distributions and seasonality test results. We performed stratified analyses by maternal and infant characteristics. Of 42 groups examined in the 15-year period, 24 (57%) had at least one statistically significant test result, suggesting a trend or seasonal variation: Cochran-Armitage (18), Hewitt-Rogerson (17), Walter-Elwood (4), and chi-square (5). Ventricular septal defect showed the most consistent results: Cochran-Armitage (p = 0.0006), Hewitt-Rogerson (December to May; p = 0.0130), Walter-Elwood (March 14; p = 0.0027), and chi-square (winter; p = 0.0046). Congenital cataract, pulmonary valve atresia/stenosis, coarctation of aorta, biliary atresia, and renal agenesis or hypoplasia had at least three significant tests. These results may help to generate hypotheses about environmental factors that vary by season for further studies. Copyright © 2012 Wiley Periodicals, Inc.

The Effects of Selection Strategies for Bivariate Loglinear Smoothing Models on NEAT Equating Functions

ERIC Educational Resources Information Center

Moses, Tim; Holland, Paul W.

2010-01-01

In this study, eight statistical strategies were evaluated for selecting the parameterizations of loglinear models for smoothing the bivariate test score distributions used in nonequivalent groups with anchor test (NEAT) equating. Four of the strategies were based on significance tests of chi-square statistics (Likelihood Ratio, Pearson,…

Factors affecting pharmacy engagement and pharmacy customer devotion in community pharmacy: A structural equation modeling approach.

PubMed

Nitadpakorn, Sujin; Farris, Karen B; Kittisopee, Tanattha

2017-01-01

The concept of customer engagement and devotion has been applied in various service businesses to keep the customers with business However, a limited number of studies were performed to examine the context of customer engagement and devotion in pharmacy business which focus on the impact of customer perceptions about pharmacists, perceived quality of pharmacy structure, medication price strategy on pharmacy engagement and pharmacy customer devotion in a pharmacy providing pharmaceutical care to the customers. This study aimed to assess a conceptual model depicting the relationships among customer perceptions about pharmacists, pharmacy quality structure, medication price, customer engagement, and customer devotion. And also aimed to assess and measure if there is a direct or indirect relationship between these factors. A quantitative study was conducted by using self-administered questionnaires. Two hundred and fifty three customers who regularly visited the pharmacy were randomly recruited from a purposively selected 30 community pharmacies in Bangkok. The survey was completed during February to April 2016. A structural equation model (SEM) was used to assess the direct and indirect relationships between constructs. A total of 253/300 questionnaires were returned for analysis, and the response rate was 84%. Only perceptions about pharmacist in customers receiving professional pharmacy services was statically significant regarding relationship with pharmacy engagement (beta=0.45). Concurrently, the model from empirical data fit with the hypothetical model (p-value = 0.06, adjusted chi-square (CMIN/DF)=1.16, Goodness of Fit Index (GFI)=0.93, Comparatively Fit Index (CFI)=0.99, and Root Mean Square Error Approximation (RMSEA)=0.03). The study confirmed the indirect positive influence of customer perceptions about pharmacist on pharmacy customer devotion in providing pharmacy services via pharmacy engagement It was customer perceptions about pharmacist that influenced customer retention, positive word of mouth and constructive advice to pharmacies, not quality of pharmacy structure and medication price. To create a long term impact on community pharmacy business, pharmacist is the key success factor.

Some Exact Conditional Tests of Independence for R X C Cross-Classification Tables

ERIC Educational Resources Information Center

Agresti, Alan; Wackerly, Dennis

1977-01-01

Exact conditional tests of independence in cross-classification tables are formulated based on chi square and other statistics with stronger operational interpretations, such as some nominal and ordinal measures of association. Guidelines for table dimensions and sample sizes for which the tests are economically implemented on a computer are…

Ensuring Positiveness of the Scaled Difference Chi-Square Test Statistic

ERIC Educational Resources Information Center

Satorra, Albert; Bentler, Peter M.

2010-01-01

A scaled difference test statistic T[tilde][subscript d] that can be computed from standard software of structural equation models (SEM) by hand calculations was proposed in Satorra and Bentler (Psychometrika 66:507-514, 2001). The statistic T[tilde][subscript d] is asymptotically equivalent to the scaled difference test statistic T[bar][subscript…

An Evaluation of Statistical Strategies for Making Equating Function Selections. Research Report. ETS RR-08-60

ERIC Educational Resources Information Center

Moses, Tim

2008-01-01

Nine statistical strategies for selecting equating functions in an equivalent groups design were evaluated. The strategies of interest were likelihood ratio chi-square tests, regression tests, Kolmogorov-Smirnov tests, and significance tests for equated score differences. The most accurate strategies in the study were the likelihood ratio tests…

Prognostic Significance of Modified Advanced Lung Cancer Inflammation Index (ALI) in Patients with Small Cell Lung Cancer_ Comparison with Original ALI.

PubMed

Kim, Eun Young; Kim, Nambeom; Kim, Young Saing; Seo, Ja-Young; Park, Inkeun; Ahn, Hee Kyung; Jeong, Yu Mi; Kim, Jeong Ho

2016-01-01

Advanced lung cancer inflammation index (ALI, body mass index [BMI] x serum albumin/neutrophil-lymphocyte ratio [NLR]) has been shown to predict overall survival (OS) in small cell lung cancer (SCLC). CT enables skeletal muscle to be quantified, whereas BMI cannot accurately reflect body composition. The purpose was to evaluate prognostic value of modified ALI (mALI) using CT-determined L3 muscle index (L3MI, muscle area at L3/height2) beyond original ALI. L3MIs were calculated using the CT images of 186 consecutive patients with SCLC taken at diagnosis, and mALI was defined as L3MI x serum albumin/NLR. Using chi-squared test determined maximum cut-offs for low ALI and low mALI, the prognostic values of low ALI and low mALI were tested using Kaplan-Meier method and Cox proportional hazards analysis. Finally, deviance statistics was used to test whether the goodness of fit of the prognostic model is improved by adding mALI as an extra variable. Patients with low ALI (cut-off, 31.1, n = 94) had shorter OS than patients with high ALI (median, 6.8 months vs. 15.8 months; p < 0.001), and patients with low mALI (cut-off 67.7, n = 94) had shorter OS than patients with high mALI (median, 6.8 months vs. 16.5 months; p < 0.001). There was no significant difference in estimates of median survival time between low ALI and low mALI (z = 0.000, p = 1.000) and between high ALI and high mALI (z = 0.330, p = 0.740). Multivariable analysis showed that low ALI was an independent prognostic factor for shorter OS (HR, 1.67, p = 0.004), along with advanced age (HR, 1.49, p = 0.045), extensive disease (HR, 2.27, p < 0.001), supportive care only (HR, 7.86, p < 0.001), and elevated LDH (HR, 1.45, p = 0.037). Furthermore, goodness of fit of this prognostic model was not significantly increased by adding mALI as an extra variable (LR difference = 2.220, p = 0.136). The present study confirms mALI using CT-determined L3MI has no additional prognostic value beyond original ALI using BMI. ALI is a simple and useful prognostic indicator in SCLC.

Impact of structural and psychological empowerment on job strain in nursing work settings: expanding Kanter's model.

PubMed

Laschinger, H K; Finegan, J; Shamian, J; Wilk, P

2001-05-01

In this study, we tested an expanded model of Kanter's structural empowerment, which specified the relationships among structural and psychological empowerment, job strain, and work satisfaction. Strategies proposed in Kanter's empowerment theory have the potential to reduce job strain and improve employee work satisfaction and performance in current restructured healthcare settings. The addition to the model of psychological empowerment as an outcome of structural empowerment provides an understanding of the intervening mechanisms between structural work conditions and important organizational outcomes. A predictive, nonexperimental design was used to test the model in a random sample of 404 Canadian staff nurses. The Conditions of Work Effectiveness Questionnaire, the Psychological Empowerment Questionnaire, the Job Content Questionnaire, and the Global Satisfaction Scale were used to measure the major study variables. Structural equation modelling analyses revealed a good fit of the hypothesized model to the data based on various fit indices (chi 2 = 1140, df = 545, chi 2/df ratio = 2.09, CFI = 0.986, RMSEA = 0.050). The amount of variance accounted for in the model was 58%. Staff nurses felt that structural empowerment in their workplace resulted in higher levels of psychological empowerment. These heightened feelings of psychological empowerment in turn strongly influenced job strain and work satisfaction. However, job strain did not have a direct effect on work satisfaction. These results provide initial support for an expanded model of organizational empowerment and offer a broader understanding of the empowerment process.

Measurement of sigma chi c2 B(chi c2-->J/psi gamma)/sigma chi c1 B(chi c1 -->J/psi gamma) in pp collisions at square root s=1.96 TeV.

PubMed

Abulencia, A; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arguin, J-F; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Budroni, S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carillo, S; Carlsmith, D; Carosi, R; Carron, S; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Ciljak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Cyr, D; DaRonco, S; Datta, M; D'Auria, S; Davies, T; D'Onofrio, M; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; Dell'Orso, M; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; DiTuro, P; Dörr, C; Donati, S; Donega, M; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Griffiths, M; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jensen, H; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kovalev, A; Kraan, A C; Kraus, J; Kravchenko, I; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Manca, G; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Nachtman, J; Nagano, A; Naganoma, J; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nigmanov, T; Nodulman, L; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Osterberg, K; Pagliarone, C; Palencia, E; Papadimitriou, V; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ranjan, N; Rappoccio, S; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Sabik, S; Safonov, A; Sakumoto, W K; Salamanna, G; Saltó, O; Saltzberg, D; Sánchez, C; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyrla, A; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Sjolin, J; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tsuchiya, R; Tsuno, S; Turini, N; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Veramendi, G; Veszpremi, V; Vidal, R; Vila, I; Vilar, R; Vine, T; Vollrath, I; Volobouev, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, J; Wagner, W; Wallny, R; Wang, S M; Warburton, A; Waschke, S; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zhou, J; Zucchelli, S

2007-06-08

We measure the ratio of cross section times branching fraction, Rp=sigma chi c2 B(chi c2-->J/psi gamma)/sigma chi c1 B(chi c1-->J/psi gamma), in 1.1 fb(-1) of pp collisions at square root s=1.96 TeV. This measurement covers the kinematic range pT(J/psi)>4.0 GeV/c, |eta(J/psi)<1.0, and pT(gamma)>1.0 GeV/c. For events due to prompt processes, we find Rp=0.395+/-0.016(stat)+/-0.015(syst). This result represents a significant improvement in precision over previous measurements of prompt chi c1,2 hadro production.

Selecting predictors for discriminant analysis of species performance: an example from an amphibious softwater plant.

PubMed

Vanderhaeghe, F; Smolders, A J P; Roelofs, J G M; Hoffmann, M

2012-03-01

Selecting an appropriate variable subset in linear multivariate methods is an important methodological issue for ecologists. Interest often exists in obtaining general predictive capacity or in finding causal inferences from predictor variables. Because of a lack of solid knowledge on a studied phenomenon, scientists explore predictor variables in order to find the most meaningful (i.e. discriminating) ones. As an example, we modelled the response of the amphibious softwater plant Eleocharis multicaulis using canonical discriminant function analysis. We asked how variables can be selected through comparison of several methods: univariate Pearson chi-square screening, principal components analysis (PCA) and step-wise analysis, as well as combinations of some methods. We expected PCA to perform best. The selected methods were evaluated through fit and stability of the resulting discriminant functions and through correlations between these functions and the predictor variables. The chi-square subset, at P < 0.05, followed by a step-wise sub-selection, gave the best results. In contrast to expectations, PCA performed poorly, as so did step-wise analysis. The different chi-square subset methods all yielded ecologically meaningful variables, while probable noise variables were also selected by PCA and step-wise analysis. We advise against the simple use of PCA or step-wise discriminant analysis to obtain an ecologically meaningful variable subset; the former because it does not take into account the response variable, the latter because noise variables are likely to be selected. We suggest that univariate screening techniques are a worthwhile alternative for variable selection in ecology. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

A Comparison of Pictorial and Speech Warning Messages in the Modern Cockpit.

DTIC Science & Technology

1984-12-01

Significance Tests for Video Game Score in Experiment One .................................... 81 5. Significance Tests for Response Time in...91 7. Significance Tests for Video Game Score in Experiment Two ..................................... 96 8. Significance Tests for Response Time in...107 10. Significance Tests for Video Game Score in Experiment Three ................................. 112 Appendix Table 1C. Chi-Square Tests for

A Tutorial for the Student Edition (Release 1.1) of Minitab.

ERIC Educational Resources Information Center

MacFarland, Thomas W.; Hou, Cheng-I

This guide for using Minitab requires DOS version 2.0 or greater, 512K RAM memory, two double-sided diskette drives, and a graphics monitor. Topics covered in the tutorial are Getting started; Installation; Making a data diskette; Entering data; Central tendency and dispersion; t-test; Chi-square test; Oneway ANOVA test; Twoway ANOVA test; and…

Health Promotion Behavior of Chinese International Students in Korea Including Acculturation Factors: A Structural Equation Model.

PubMed

Kim, Sun Jung; Yoo, Il Young

2016-03-01

The purpose of this study was to explain the health promotion behavior of Chinese international students in Korea using a structural equation model including acculturation factors. A survey using self-administered questionnaires was employed. Data were collected from 272 Chinese students who have resided in Korea for longer than 6 months. The data were analyzed using structural equation modeling. The p value of final model is .31. The fitness parameters of the final model such as goodness of fit index, adjusted goodness of fit index, normed fit index, non-normed fit index, and comparative fit index were more than .95. Root mean square of residual and root mean square error of approximation also met the criteria. Self-esteem, perceived health status, acculturative stress and acculturation level had direct effects on health promotion behavior of the participants and the model explained 30.0% of variance. The Chinese students in Korea with higher self-esteem, perceived health status, acculturation level, and lower acculturative stress reported higher health promotion behavior. The findings can be applied to develop health promotion strategies for this population. Copyright © 2016. Published by Elsevier B.V.

Validation of the Spanish Version of the Quality of Dying and Death Questionnaire (QODD-ESP) in a Home-Based Cancer Palliative Care Program and Development of the QODD-ESP-12.

PubMed

Pérez-Cruz, Pedro E; Padilla Pérez, Oslando; Bonati, Pilar; Thomsen Parisi, Oliva; Tupper Satt, Laura; Gonzalez Otaiza, Marcela; Ceballos Yáñez, Diego; Maldonado Morgado, Armando

2017-06-01

Improving quality of death (QOD) is a key goal in palliative care (PC). To our knowledge, no instruments to measure QOD have been validated in Spanish. The goals of this study were to validate the Spanish version of the quality of dying and death (QODD) questionnaire and to develop and validate a shortened version of this instrument by phone interview. We enrolled caregivers (CGs) of consecutive deceased cancer patients who participated in a single PC clinic. CGs were contacted by phone between 4 and 12 weeks after patients' death and completed the Spanish QODD (QODD-ESP). A question assessing quality of life during last week of life was included. A 12-item QODD (QODD-ESP-12) was developed. Reliability, convergent validity, and construct validity were estimated for both versions. About 150 (50%) of 302 CGs completed the QODD-ESP. Patient's mean age (SD) was 67 (14); 71 (47%) were females, and 131 (87%) died at home. CGs' mean age (SD) was 51 (13); 128 (85%) were females. Mean QODD-ESP score was 69 (range 35-96). Kaiser-Meyer-Olkin measure of sampling adequacy was 0.322, not supporting the use of factorial analysis to assess the existence of an underlying construct. Mean QODD-ESP-12 score was 69 (range 31-97). Correlation with last week quality of life was 0.306 (P < 0.01). Confirmatory factorial analysis of QODD-ESP-12 showed that data fitted well Downey's four factors; Chi-square test = 6.32 (degrees of freedom = 60), P = 0.394 comparative fit index = 0.988; Tucker-Lewis Index = 0.987, and root mean square error of approximation = 0.016 (95% CI 0-0.052). QODD-ESP-12 is a reliable and valid instrument with good psychometric properties and can be used to assess QOD in a Spanish-speaking cancer PC population by phone interview. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Role of general and specific competence skills in protecting inner-city adolescents from alcohol use.

PubMed

Epstein, J A; Griffin, K W; Botvin, G J

2000-05-01

The purpose of this longitudinal investigation was to test whether higher levels of general competence are linked to greater refusal assertiveness that is, in turn, related to less subsequent alcohol use among inner-city adolescents. A large sample of students attending 22 middle and junior high schools in New York City participated. Students completed surveys at baseline, at 1-year follow-up and at 2-year follow-up (N = 1,459; 54% female). The students self-reported alcohol use. decision-making skills, self-efficacy and refusal assertiveness. Teams of three to five data collectors administered the questionnaire following a standardized protocol. The data were collected in school during a regular 40-minute class period. According to the tested structural equation model, Decision Making (beta = .07, p < .05) and Self-Efficacy (beta = .24, p < .001) predicted higher Refusal Assertiveness and this greater assertiveness predicted less drinking at the 2-year follow-up (beta = -.21, p < .001). Earlier drinking predicted 2-year follow-up drinking (beta = .40, p < .001). Goodness-of-fit indices were excellent (chi2 = 1107.9, 238 df, N = 1,438, p < .001; NFI = .93, NNFI = .94, CFI = .95). The tested model had a good fit and was parsimonious and consistent with theory. This research highlights the importance of addressing decision-making skills, self-efficacy and refusal assertiveness within adolescent alcohol prevention programs.

Quality of residential care for older people: does education for healthcare assistants make a difference?

PubMed

Smith, Barbara; Kerse, Ngaire; Parsons, Matthew

2005-05-06

To determine the impact of a healthcare assistant education programme on the quality of care for older people living in a residential home in Auckland, New Zealand. A pre- and post-intervention evaluation study was undertaken within a residential home for older people. Quality of care was established by two periods of non-participant time-sampling observation of residents, separated by a programme of 10 interactive teaching sessions for healthcare assistants. Informed consent was gained from all observed residents and staff. Using the Quality Assessment Project (QAP) quality measure, the non-participant time-sampling observation data identified a 12.5% increase in resident care that was considered appropriate and adequate (chi-squared=12.05) and an 11.53% decrease in resident care that was considered inappropriate and inadequate (chi-squared=11.43). The intermediate grades did not alter significantly. Residents with low functional activity scores (Barthel Index) received better care after the education intervention (chi-squared=32.99), as did residents with moderate cognitive impairment (Abbreviated Mental Test Score [AMTS]<8/10). Healthcare assistant education can positively impact on the quality of care given to older people in residential care.

Chi-Square Statistics, Tests of Hypothesis and Technology.

ERIC Educational Resources Information Center

Rochowicz, John A.

The use of technology such as computers and programmable calculators enables students to find p-values and conduct tests of hypotheses in many different ways. Comprehension and interpretation of a research problem become the focus for statistical analysis. This paper describes how to calculate chisquare statistics and p-values for statistical…

A Probability Based Framework for Testing the Missing Data Mechanism

ERIC Educational Resources Information Center

Lin, Johnny Cheng-Han

2013-01-01

Many methods exist for imputing missing data but fewer methods have been proposed to test the missing data mechanism. Little (1988) introduced a multivariate chi-square test for the missing completely at random data mechanism (MCAR) that compares observed means for each pattern with expectation-maximization (EM) estimated means. As an alternative,…

STUDIES IN RESEARCH METHODOLOGY. IV. A SAMPLING STUDY OF THE CENTRAL LIMIT THEOREM AND THE ROBUSTNESS OF ONE-SAMPLE PARAMETRIC TESTS,

DTIC Science & Technology

iconoclastic . Even at N=1024 these departures were quite appreciable at the testing tails, being greatest for chi-square and least for Z, and becoming worse in all cases at increasingly extreme tail areas. (Author)

Frequency of in-hospital acquired staphylococcus bacteremia/sepsis within ten-year period.

PubMed

Pitic, Aida; Lukovac, Enra; Koluder, Nada; Baljic, Rusmir

2013-01-01

Analyzing data in the literature, it is noted that in-hospital acquired infections are an increasing problem even in more developed countries. This increasing trend is related to the progress of medical science and introduction of new invasive diagnostic-therapeutic methods, as well as increase of multiresistant types of bacteria, including staphylococci in big percentages. To analyze frequency of in-hospital acquired staphylococcus bacteremia/sepsis. Anamneses of patients who were diagnosed with staphylococcus bacteremia/sepsis were analyzed within a ten-year period. Within the analyzed period from 2001 to 2011, there were 87 patients with diagnosis of staphylococcus bacteremia/sepsis, out of which (20) 77% were diagnosed with sepsis, and (67) 23% with bacteremia. In-hospital outcome was present with 32 (36.8%) patients, while 55 (63.2%) were out of hospital. The chi-square test for independence showed that the diagnosis of bacteremia/sepsis and the place of the infection origin (in hospital/ out of hospital) were independent chi2 = 1.951 df= 1 p=0.162. The cause isolated from hemoculture depends on the place of the infection origin (out of hospital/in hospital); larger percentage of methicillin-resistant types was presented in in-hospital acquired infections chi2 11.352 df=1 p=0.001. And the chi-square test for independence showed both dependence of the preceding antibiotic treatment and the place of the infection origin in both categories of patients. Sepsis: chi2 = 22.92 df=1 p<0.0005; Bacteremia: chi2 = 9.89 df=1 p= 0.005. The results showed larger percentage of methicillin-resistant types in in-hospital acquired infections, as well as significantly larger percentage of hospital infections with the preceding antibiotic therapy, which puts in focus possible rationalization of including antibiotic therapy.

Examples of Data Analysis with SPSS-X.

ERIC Educational Resources Information Center

MacFarland, Thomas W.

Intended for classroom use only, these unpublished notes contain computer lessons on descriptive statistics using SPSS-X Release 3.0 for VAX/UNIX. Statistical measures covered include Chi-square analysis; Spearman's rank correlation coefficient; Student's t-test with two independent samples; Student's t-test with a paired sample; One-way analysis…

Psychometric properties and Confirmatory structure of the Strengths and difficulties questionnaire in a sample of adolescents in Nigeria.

PubMed

Akpa, Onoja M; Afolabi, Rotimi F; Fowobaje, Kayode R

Though the SDQ has been used in selected studies in Nigeria, its theoretical structure has not been fully and appropriately investigated in the setting. The present study employs Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) to investigate the theoretical structure of the self-reported version of the SDQ in a sample of adolescents in Benue state, Nigeria. A total of 1,244 adolescents from different categories of secondary schools in Makurdi and Vandekya Local government areas of Benue state participated in the study. Preliminary data analyses were performed using descriptive statistics while the theoretical structure of the SDQ was assessed using EFA and CFA. Model fits were assessed using Chi-square test and other fit indices at 5% significance level. Participants were 14.19±2.45 (Vandekya) and 14.19±2.45 (Makurdi) years old. Results of the EFA and CFA revealed a 3-factor oblique model as the best model for the sample of adolescents studied ( χ 2 / df =2.20, p<0.001) with all fit indices yielding better results. A correlated 3-factor model fits the present data better than the 5-factor theoretical model of the SDQ. The use of the original 5-factor model of the SDQ in the present setting should be interpreted with caution.

Detecting Reddening by Dust for Star Clusters in the Andromeda Galaxy

NASA Astrophysics Data System (ADS)

Cohn, Amy; Dorman, C.; Guhathakurta, P.; PHAT Collaboration

2014-01-01

We have developed a technique to detect reddening by interstellar dust of star clusters in the Andromeda Galaxy, using Hubble Space Telescope ACS/WFC imaging in B and I and spectroscopic data from Keck II DEIMOS spectrograph. These data are from the Panchromatic Hubble Andromeda Treasury (PHAT) and Spectroscopic and Panchromatic Landscape of Andromeda's Stellar Halo (SPLASH) surveys. We compared the observed color indices from the PHAT data to the intrinsic color indices quantitatively inferred from a chi-squared goodness of fit comparison between the SPLASH data and a library of template spectra, to detect reddening. The spectral comparison utilizes the strength of the titanium oxide bands. This technique will be applied to an additional 150 star clusters, in Andromeda, to determine the amount of reddening they have experienced. It will also be used as part of the process of correcting for the reddening, developing a reddening law, and learning more about the physical properties of the dust. This research was carried out under the auspices of UCSC's Science Internship Program. We thank the National Aeronautics and Space Administration and the National Science Foundation for funding support.

Intimate partner violence in Europe: design and methods of a multinational study.

PubMed

Costa, Diogo; Soares, Joaquim J F; Lindert, Jutta; Hatzidimitriadou, Eleni; Karlsso, Andreas; Sundin, Örjan; Toth, Olga; Ioannidi-Kapolou, Ellisabeth; Degomme, Olivier; Cervilla, Jorge; Barros, Henrique

2013-01-01

To describe the design, methods, procedures and characteristics of the population involved in a study designed to compare Intimate Partner Violence (IPV) in eight European countries. Women and men aged 18-65, living in Ghent-Belgium (n = 245), Stuttgart-Germany (n = 546), Athens-Greece (n = 548), Budapest-Hungary (n = 604), Porto-Portugal (n = 635), Granada-Spain (n = 138), Östersund-Sweden (n = 592), London-United Kingdom (n = 571), were sampled and administered a common questionnaire. Chi-square goodness of fit and five-age strata population fractions ratios for sex and education were computed to evaluate samples' representativeness. Differences in the age distributions were found among women from Sweden and Portugal and among men from Belgium, Hungary, Portugal and Sweden. Over-recruitment of more educated respondents was noted in all sites. The use of a common research protocol with the same structured questionnaire is likely to provide accurate estimates of the general population IPV frequency, despite limitations in probabilistic sampling and restrictions in methods of administration. Copyright © 2012 SESPAS. Published by Elsevier Espana. All rights reserved.

Using statistical process control for monitoring the prevalence of hospital-acquired pressure ulcers.

PubMed

Kottner, Jan; Halfens, Ruud

2010-05-01

Institutionally acquired pressure ulcers are used as outcome indicators to assess the quality of pressure ulcer prevention programs. Determining whether quality improvement projects that aim to decrease the proportions of institutionally acquired pressure ulcers lead to real changes in clinical practice depends on the measurement method and statistical analysis used. To examine whether nosocomial pressure ulcer prevalence rates in hospitals in the Netherlands changed, a secondary data analysis using different statistical approaches was conducted of annual (1998-2008) nationwide nursing-sensitive health problem prevalence studies in the Netherlands. Institutions that participated regularly in all survey years were identified. Risk-adjusted nosocomial pressure ulcers prevalence rates, grade 2 to 4 (European Pressure Ulcer Advisory Panel system) were calculated per year and hospital. Descriptive statistics, chi-square trend tests, and P charts based on statistical process control (SPC) were applied and compared. Six of the 905 healthcare institutions participated in every survey year and 11,444 patients in these six hospitals were identified as being at risk for pressure ulcers. Prevalence rates per year ranged from 0.05 to 0.22. Chi-square trend tests revealed statistically significant downward trends in four hospitals but based on SPC methods, prevalence rates of five hospitals varied by chance only. Results of chi-square trend tests and SPC methods were not comparable, making it impossible to decide which approach is more appropriate. P charts provide more valuable information than single P values and are more helpful for monitoring institutional performance. Empirical evidence about the decrease of nosocomial pressure ulcer prevalence rates in the Netherlands is contradictory and limited.

In vitro evaluation of the sealing ability of three newly developed root canal sealers: A bacterial microleakage study

PubMed Central

Sobhani, Ehsan; Samadi-Kafil, Hossein; Pirzadeh, Ahmad; Jafari, Sanaz

2016-01-01

Background The purpose of this study was to compare the sealing ability of MTA Fillapex, Apatite Root Canal Sealer and AH26 sealers. Material and Methods The present in vitro study was carried out on 142 extracted single-rooted human mature teeth. The teeth were randomly divided into three experimental groups (n=44) and two control groups (n=5). Three root canal sealers were MTA Fillapex, Apatite Root Canal Sealer and AH26. The teeth in the control groups were either filled with no sealer or made completely impermeable. The root canals were prepared and obturated with gutta-percha and one of the sealers. The teeth were sterilized with ethylene oxide gas prior to the bacterial leakage assessment using Enterococcus faecalis. Leakage was evaluated every 24 hours for 90 days. Data were analyzed with descriptive statistical methods and chi-squared test. If the data were significant, a proper post hoc test was used. Statistical significance was set at P<0.05. Results The positive control specimens exhibited total bacterial penetration whilst the negative control specimens showed no evidence of bacterial penetration. At the end of the study, the analysis of microleakage with chi-squared test showed no significant differences between the experimental groups (P<0.05). The results of chi-squared test analyzing the pair-wise differences between the groups considering the numerical values for leakage day indicated the lowest leakage with AH26 and the highest with Apatite root sealer. Conclusions According to the results of the present study, sealing ability of AH26 was significantly higher than that of MTA Fillapex and Apatite Root Canal Sealer. Key words:Mineral Trioxide aggregate, root canal obturation, dental seal. PMID:27957271

Genotyping and drug resistance patterns of M. tuberculosis strains in Pakistan.

PubMed

Tanveer, Mahnaz; Hasan, Zahra; Siddiqui, Amna R; Ali, Asho; Kanji, Akbar; Ghebremicheal, Solomon; Hasan, Rumina

2008-12-24

The incidence of tuberculosis in Pakistan is 181/100,000 population. However, information about transmission and geographical prevalence of Mycobacterium tuberculosis strains and their evolutionary genetics as well as drug resistance remains limited. Our objective was to determine the clonal composition, evolutionary genetics and drug resistance of M. tuberculosis isolates from different regions of the country. M. tuberculosis strains isolated (2003-2005) from specimens submitted to the laboratory through collection units nationwide were included. Drug susceptibility was performed and strains were spoligotyped. Of 926 M. tuberculosis strains studied, 721(78%) were grouped into 59 "shared types", while 205 (22%) were identified as "Orphan" spoligotypes. Amongst the predominant genotypes 61% were Central Asian strains (CAS ; including CAS1, CAS sub-families and Orphan Pak clusters), 4% East African-Indian (EAI), 3% Beijing, 2% poorly defined TB strains (T), 2% Haarlem and LAM (0.2). Also TbD1 analysis (M. tuberculosis specific deletion 1) confirmed that CAS1 was of "modern" origin while EAI isolates belonged to "ancestral" strain types.Prevalence of CAS1 clade was significantly higher in Punjab (P < 0.01, Pearsons Chi-square test) as compared with Sindh, North West Frontier Province and Balochistan provinces. Forty six percent of isolates were sensitive to five first line antibiotics tested, 45% were Rifampicin resistant, 50% isoniazid resistant. MDR was significantly associated with Beijing strains (P = 0.01, Pearsons Chi-square test) and EAI (P = 0.001, Pearsons Chi-square test), but not with CAS family. Our results show variation of prevalent M. tuberculosis strain with greater association of CAS1 with the Punjab province. The fact that the prevalent CAS genotype was not associated with drug resistance is encouraging. It further suggests a more effective treatment and control programme should be successful in reducing the tuberculosis burden in Pakistan.

[Analysis of burnout and job satisfaction among nurses based on the Job Demand-Resource Model].

PubMed

Yom, Young-Hee

2013-02-01

The purpose of this study was to examine burnout and job satisfaction among nurses based on Job Demand-Resource Model. A survey using a structured questionnaire was conducted with 464 hospital nurses. Analysis of data was done with both SPSS Win 17.0 for descriptive statistics and AMOS 18.0 for the structural equation model. The hypothetical model yielded the following Chi-square=34.13 (p = <.001), df=6, GFI=.98, AGFI=.92, CFI=.94, RMSR=.02, NFI=.93, IFI=.94 and showed good fit indices. Workload had a direct effect on emotional exhaustion (β = 0.39), whereas supervisor support had direct effects on emotional exhaustion (β = -0.24), depersonalization (β = -0.11), and low personal accomplishment (β = -0.22). Emotional exhaustion (β = -0.42), depersonalization (β = -0.11) and low personal accomplishment (β = -0.36) had significant direct effects on job satisfaction. The results suggest that nurses' workload should be decreased and supervisor's support should be increased in order to retain nurses. Further study with a longitudinal design is necessary.

How well will you FIT? Use of a modified MMI to assess applicants’ compatibility with an emergency medicine residency program

PubMed Central

Min, Alice A.; Leetch, Aaron; Nuño, Tomas; Fiorello, Albert B.

2016-01-01

Purpose Emergency medicine residency programs have evaluated the use of Multiple Mini Interviews (MMIs) for applicants. The authors developed an MMI-style method called the Fast Interview Track (FIT) to predict an applicant's ‘fit’ within an individual residency program. Methods Applicants meet with up to five residents and are asked one question by each. Residents score the applicant using a Likert scale from 1 to 5 on two questions: ‘How well does the applicant think on his/her feet?’ and ‘How well do you think the applicant will fit in here?’. To assess how well these questions predicted a resident's ‘fit’, current residents scored fellow residents on these same questions. These scores were compared with the residents’ interview FIT scores. A postmatch survey of applicants who did not match at this program solicited applicants’ attitudes toward the FIT sessions. Results Among the junior class, the correlation between interview and current scores was significant for question 1 (rho=0.5192 [p=0.03]) and question 2 (rho=0.5753 [p=0.01]). Among seniors, Spearman's rho was statistically significant for question 2, though not statistically significant for question 1. The chi-square measure of high scores (4–5) versus low scores (1–3) found a statistically significant association between interview and current scores for interns and juniors. Of the 29 responses to the postmatch survey, 16 (55%) felt FIT sessions provided a good sense of the program's personality and only 6 (21%) disagreed. Nine (31%) felt FIT sessions positively impacted our program's ranking and 11 (38%) were ‘Neutral’. Only two (7%) reported that FIT sessions negatively impacted their ranking of our program. Conclusions FIT provided program leadership with a sense of an applicant's ‘fit’ within this program. Interview day scores correlated with scores received during residency. Most applicants report a positive experience with FIT sessions. FIT provides a useful tool to recruit applicants who fit with the residency program. PMID:26842824

Impact of nursing interventions on adherence to treatment with antituberculosis drugs in children and young people: A non-randomized controlled trial.

PubMed

Guix-Comellas, Eva Maria; Rozas-Quesada, Librada; Velasco-Arnaiz, Eneritz; Ferres-Canals, Ariadna; Estrada-Masllorens, Joan Maria; Force-Sanmartín, Enriqueta; Noguera-Julian, Antoni

2018-05-03

To evaluate the association of a new nursing intervention on the adherence to antituberculosis treatment in a pediatric cohort (<18 years). Tuberculosis remains a public health problem worldwide. The risk of developing tuberculosis after primary infection and its severity are higher in children. Proper adherence to antituberculosis treatment is critical for disease control. Non-randomized controlled trial; Phase 1, retrospective (2011-2013), compared with Phase 2, prospective with intervention (2015-2016), in a referral center for pediatric tuberculosis in Spain (NCT03230409). A total of 359 patients who received antituberculosis drugs after close contact with a smear-positive patient (primary chemoprophylaxis) or were treated for latent tuberculosis infection or tuberculosis disease were included, 261 in Phase 1 and 98 in Phase 2. In phase 2, a new nurse-led intervention was implemented in all patients and included two educational steps (written information in the child's native language and follow-up telephone calls) and two monitoring steps (Eidus-Hamilton test and follow-up questionnaire) that were exclusively carried out by nurses. Adherence to antituberculosis treatment increased from 74.7% in Phase 1 to 87.8% in Phase 2 (p=0.014; Chi-square test), after the implementation of the nurse-led intervention. In Phase 2, non-adherence was only associated with being born abroad (28.6% versus 7.8%; p=0.019; Chi-square test) and with foreign origin families (27.3% versus 0%; p<0.0001; Chi-square test). The nurse-led intervention was associated to an increase in adherence to antituberculosis treatment. Immigrant-related variables remained major risk factors for sub-optimal adherence in a low-endemic setting. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Relationship between Service Quality, Satisfaction, Motivation and Loyalty: A Multi-Dimensional Perspective

ERIC Educational Resources Information Center

Subrahmanyam, Annamdevula

2017-01-01

Purpose: This paper aims to identify and test four competing models with the interrelationships between students' perceived service quality, students' satisfaction, loyalty and motivation using structural equation modeling (SEM), and to select the best model using chi-square difference (??2) statistic test. Design/methodology/approach: The study…

The effect of teacher quality on the achievement of students in Integrated Physics and Chemistry

NASA Astrophysics Data System (ADS)

Alexander, Rima

For many years, researchers, policy makers, and the education community have explored various school variables and their impact on student achievement (Darling-Hammond, 2000; Ferguson and Womack 1993; Ferguson and Ladd 1996; Rice, 2003; Rockoff, 2003; Rowan, Chiang, and Miller 1997; Sanders and Horn, 1996; Wright Horn and Sanders, 1997). Invariably, the issue of teacher quality arises. Teacher quality is the single most influential factor under school control that affects student achievement (Darling-Hammond, 2000; Rice, 2003; Rockoff, 2003; Sanders and Horn, 1996; Wright Horn and Sanders, 1997). Generally, students taught by highly qualified teachers perform better on standardized tests than students with less qualified teachers (Ferguson and Womack 1993; Ferguson and Ladd 1996; Rowan, Chiang, and Miller 1997). Previous research indicates that teachers indeed matter for the improvement of student achievement, but getting good measures of what is meant by teacher quality is a continuing challenge (Goldhaber, 2002). The purpose of this study was to describe the effect of teacher quality on the achievement of students in Integrated Physics and Chemistry (IPC). In order to achieve this purpose, this study addressed the following research question: chemistry and physics teachers compare to the achievement of students taught by less-qualified IPC teachers? A causal-comparative methodology was employed to address this research question. The independent variable was teacher quality---highly-qualified or less qualified. The teacher attributes that were examined in this study are: (1) teachers' educational background; (2) content knowledge; (3) pedagogical knowledge; and (4) certification. The dependent variable was student achievement in integrated physics and chemistry, as measured by an end-of-course IPC District Assessment of Curriculum, IPC DAC. Descriptive statistics were computed for the independent variable in the study. A Chi Square was performed on the data, utilizing SPSS version 12.0.1 software. Next a test of statistical significance was done to determine whether the null hypothesis could be rejected; and whether or not the research hypothesis could be accepted. Since this is a causal comparative design with only two groups in which student achievement was measured by a test that will yield raw scores, a Chi Square was conducted to determine whether the pass rates of the two groups of students based on obtained and expected percentages were statistically significantly different A Chi Square value of 4.29 was obtained, which indicates that the pass rate for students of highly-qualified teachers was statistically significantly higher than for students of less-qualified teachers. For the purpose of this study a criterion value of (p<.05) was used.

A Method for Assessing Change in Attitude: The McNemar Test.

ERIC Educational Resources Information Center

Ciechalski, Joseph C.; Pinkney, James W.; Weaver, Florence S.

This paper illustrates the use of the McNemar Test, using a hypothetical problem. The McNemar Test is a nonparametric statistical test that is a type of chi square test using dependent, rather than independent, samples to assess before-after designs in which each subject is used as his or her own control. Results of the McNemar test make it…

Syndromes of Self-Reported Psychopathology for Ages 18-59 in 29 Societies.

PubMed

Ivanova, Masha Y; Achenbach, Thomas M; Rescorla, Leslie A; Tumer, Lori V; Ahmeti-Pronaj, Adelina; Au, Alma; Maese, Carmen Avila; Bellina, Monica; Caldas, J Carlos; Chen, Yi-Chuen; Csemy, Ladislav; da Rocha, Marina M; Decoster, Jeroen; Dobrean, Anca; Ezpeleta, Lourdes; Fontaine, Johnny R J; Funabiki, Yasuko; Guðmundsson, Halldór S; Harder, Valerie S; de la Cabada, Marie Leiner; Leung, Patrick; Liu, Jianghong; Mahr, Safia; Malykh, Sergey; Maras, Jelena Srdanovic; Markovic, Jasminka; Ndetei, David M; Oh, Kyung Ja; Petot, Jean-Michel; Riad, Geylan; Sakarya, Direnc; Samaniego, Virginia C; Sebre, Sandra; Shahini, Mimoza; Silvares, Edwiges; Simulioniene, Roma; Sokoli, Elvisa; Talcott, Joel B; Vazquez, Natalia; Zasepa, Ewa

2015-06-01

This study tested the multi-society generalizability of an eight-syndrome assessment model derived from factor analyses of American adults' self-ratings of 120 behavioral, emotional, and social problems. The Adult Self-Report (ASR; Achenbach and Rescorla 2003) was completed by 17,152 18-59-year-olds in 29 societies. Confirmatory factor analyses tested the fit of self-ratings in each sample to the eight-syndrome model. The primary model fit index (Root Mean Square Error of Approximation) showed good model fit for all samples, while secondary indices showed acceptable to good fit. Only 5 (0.06%) of the 8,598 estimated parameters were outside the admissible parameter space. Confidence intervals indicated that sampling fluctuations could account for the deviant parameters. Results thus supported the tested model in societies differing widely in social, political, and economic systems, languages, ethnicities, religions, and geographical regions. Although other items, societies, and analytic methods might yield different results, the findings indicate that adults in very diverse societies were willing and able to rate themselves on the same standardized set of 120 problem items. Moreover, their self-ratings fit an eight-syndrome model previously derived from self-ratings by American adults. The support for the statistically derived syndrome model is consistent with previous findings for parent, teacher, and self-ratings of 1½-18-year-olds in many societies. The ASR and its parallel collateral-report instrument, the Adult Behavior Checklist (ABCL), may offer mental health professionals practical tools for the multi-informant assessment of clinical constructs of adult psychopathology that appear to be meaningful across diverse societies.

Validation and uncertainty quantification of detector response functions for a 1″×2″ NaI collimated detector intended for inverse radioisotope source mapping applications

NASA Astrophysics Data System (ADS)

Nelson, N.; Azmy, Y.; Gardner, R. P.; Mattingly, J.; Smith, R.; Worrall, L. G.; Dewji, S.

2017-11-01

Detector response functions (DRFs) are often used for inverse analysis. We compute the DRF of a sodium iodide (NaI) nuclear material holdup field detector using the code named g03 developed by the Center for Engineering Applications of Radioisotopes (CEAR) at NC State University. Three measurement campaigns were performed in order to validate the DRF's constructed by g03: on-axis detection of calibration sources, off-axis measurements of a highly enriched uranium (HEU) disk, and on-axis measurements of the HEU disk with steel plates inserted between the source and the detector to provide attenuation. Furthermore, this work quantifies the uncertainty of the Monte Carlo simulations used in and with g03, as well as the uncertainties associated with each semi-empirical model employed in the full DRF representation. Overall, for the calibration source measurements, the response computed by the DRF for the prediction of the full-energy peak region of responses was good, i.e. within two standard deviations of the experimental response. In contrast, the DRF tended to overestimate the Compton continuum by about 45-65% due to inadequate tuning of the electron range multiplier fit variable that empirically represents physics associated with electron transport that is not modeled explicitly in g03. For the HEU disk measurements, computed DRF responses tended to significantly underestimate (more than 20%) the secondary full-energy peaks (any peak of lower energy than the highest-energy peak computed) due to scattering in the detector collimator and aluminum can, which is not included in the g03 model. We ran a sufficiently large number of histories to ensure for all of the Monte Carlo simulations that the statistical uncertainties were lower than their experimental counterpart's Poisson uncertainties. The uncertainties associated with least-squares fits to the experimental data tended to have parameter relative standard deviations lower than the peak channel relative standard deviation in most cases and good reduced chi-square values. The highest sources of uncertainty were identified as the energy calibration polynomial factor (due to limited source availability and NaI resolution) and the Ba-133 peak fit (only a very weak source was available), which were 20% and 10%, respectively.

Design and validation of a self-administered test to assess bullying (bull-M) in high school Mexicans: a pilot study.

PubMed

Ramos-Jimenez, Arnulfo; Wall-Medrano, Abraham; Villar, Oscar Esparza-Del; Hernández-Torres, Rosa P

2013-04-11

Bullying (Bull) is a public health problem worldwide, and Mexico is not exempt. However, its epidemiology and early detection in our country is limited, in part, by the lack of validated tests to ensure the respondents' anonymity. The aim of this study was to validate a self-administered test (Bull-M) for assessing Bull among high-school Mexicans. Experts and school teachers from highly violent areas of Ciudad Juarez (Chihuahua, México), reported common Bull behaviors. Then, a 10-item test was developed based on twelve of these behaviors; the students' and peers' participation in Bull acts and in some somatic consequences in Bull victims with a 5-point Likert frequency scale. Validation criteria were: content (CV, judges); reliability [Cronbach's alpha (CA), test-retest (spearman correlation, rs)]; construct [principal component (PCA), confirmatory factor (CFA), goodness-of-fit (GF) analysis]; and convergent (Bull-M vs. Bull-S test) validity. Bull-M showed good reliability (CA = 0.75, rs = 0.91; p < 0.001). Two factors were identified (PCA) and confirmed (CFA): "bullying me (victim)" and "bullying others (aggressor)". GF indices were: Root mean square error of approximation (0.031), GF index (0.97), and normalized fit index (0.92). Bull-M was as good as Bull-S for measuring Bull prevalence. Bull-M has a good reliability and convergent validity and a bi-modal factor structure for detecting Bull victims and aggressors; however, its external validity and sensitivity should be analyzed on a wider and different population.

Biology Notes.

ERIC Educational Resources Information Center

School Science Review, 1983

1983-01-01

Describes laboratory procedures, demonstrations, and classroom activities/materials, including chi-square tests on a microcomputer, an integrated biology game, microscope slides of leaf stomata, culturing soil nematodes, technique for watering locust egg-laying tubes, hazards of biological chemicals (such as benzene, benzidene, calchicine,…

A New Algorithm to Optimize Maximal Information Coefficient

PubMed Central

Luo, Feng; Yuan, Zheming

2016-01-01

The maximal information coefficient (MIC) captures dependences between paired variables, including both functional and non-functional relationships. In this paper, we develop a new method, ChiMIC, to calculate the MIC values. The ChiMIC algorithm uses the chi-square test to terminate grid optimization and then removes the restriction of maximal grid size limitation of original ApproxMaxMI algorithm. Computational experiments show that ChiMIC algorithm can maintain same MIC values for noiseless functional relationships, but gives much smaller MIC values for independent variables. For noise functional relationship, the ChiMIC algorithm can reach the optimal partition much faster. Furthermore, the MCN values based on MIC calculated by ChiMIC can capture the complexity of functional relationships in a better way, and the statistical powers of MIC calculated by ChiMIC are higher than those calculated by ApproxMaxMI. Moreover, the computational costs of ChiMIC are much less than those of ApproxMaxMI. We apply the MIC values tofeature selection and obtain better classification accuracy using features selected by the MIC values from ChiMIC. PMID:27333001

Modelling lifetime data with multivariate Tweedie distribution

NASA Astrophysics Data System (ADS)

Nor, Siti Rohani Mohd; Yusof, Fadhilah; Bahar, Arifah

2017-05-01

This study aims to measure the dependence between individual lifetimes by applying multivariate Tweedie distribution to the lifetime data. Dependence between lifetimes incorporated in the mortality model is a new form of idea that gives significant impact on the risk of the annuity portfolio which is actually against the idea of standard actuarial methods that assumes independent between lifetimes. Hence, this paper applies Tweedie family distribution to the portfolio of lifetimes to induce the dependence between lives. Tweedie distribution is chosen since it contains symmetric and non-symmetric, as well as light-tailed and heavy-tailed distributions. Parameter estimation is modified in order to fit the Tweedie distribution to the data. This procedure is developed by using method of moments. In addition, the comparison stage is made to check for the adequacy between the observed mortality and expected mortality. Finally, the importance of including systematic mortality risk in the model is justified by the Pearson's chi-squared test.

Pasta Predation.

ERIC Educational Resources Information Center

Waugh, Michael L.

1986-01-01

Presents a predator-prey simulation which involves students in collecting data, solving problems, and making predictions on the evolution of prey populations. Provides directives on how to perform the chi-square test and also includes an Applesoft BASK program that performs the calculations. (ML)

Rugby Union on-field position and its relationship to shoulder injury leading to anterior reconstruction for instability.

PubMed

Sundaram, Abayasankar; Bokor, Desmond J; Davidson, Andrew S

2011-03-01

Due to the unique demands of each position on the Rugby Union field, the likelihood of an athlete sustaining a dislocation of their shoulder joint that requires surgical reconstruction may be affected by their position on the field. 166 patients with 184 involved shoulders requiring anterior reconstruction following an on-field Rugby Union injury between January 1996 and September 2008 were analysed. The mean age at time of injury was 18 years with the mean age at time of surgery being 20 years. The most prevalent mechanism of injury was a tackle in 66.3% of players. Players were more likely to suffer injury to their non-dominant shoulder than their dominant side (McNemar's Test, p<0.001). Statistical analysis using chi-squared test of goodness of fit showed there was not a uniform risk of injury for all player positions. Positions with significantly different risk of injury were five-eighth (increased risk) and wing (reduced risk). Although we observed an increased risk in flankers and fullbacks, and a lower risk in second row, these results did not reach statistical significance after application of the Bonferroni correction. This information can be utilized by team staff to assist in pre-season conditioning as well as the development of improved muscle co-ordination programmes for the non-dominant shoulder, and planning a graduated return to sport by the player recovering from surgical reconstruction of the shoulder for instability. Copyright © 2010 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Medicine and Physiotherapy students: are they physically active? Comparative research on Spanish and German population.

PubMed

Zeńczak-Praga, Krystyna; Pluto-Prondzinska, Joanna; Zgorzalewicz-Stachowiak, Małgorzata

2017-05-23

Despite the fact that regular physical activity is beneficial to human life, there are still more and more overweight and obese people throughout the world today. Healthy habits taken from home or socioeconomic situation are factors which might influence on regular physical activity. People who lead a healthy lifestyle in childhood are also active during adulthood. On the other hand academic life might promote less healthy lifestyle. The aim of the study was to assess and compare the level of physical activity of both German and Spanish students of Medicine and Physiotherapy. The study involved 100 Spanish and 100 German students aged from 19 to 24 years. Based on Eurobarometer 72.3, the respondents were asked a set of questions regarding physical activity. The chi-squared test (χ2) and Mann-Whitney U test were used for the statistical analysis. The vast majority of students presented a normal BMI value, but it was not related to high physical activity. More than one-third of all students seldom practised any sports. The Spanish students usually did some form of physical activity outdoors, whereas the German students exercised in a fitness centre. Lack of time was to the Medicine and Physiotherapy students the most significant factor that did not allow them to be more physically active. Medicine and Physiotherapy students should be more physically active in order to promote a good, healthy lifestyle model to society and there should be more physical activity education to encourage more students to practise sports.

Use of a non-linear method for including the mass uncertainty of gravimetric standards and system measurement errors in the fitting of calibration curves for XRFA freeze-dried UNO/sub 3/ standards

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

Pickles, W.L.; McClure, J.W.; Howell, R.H.

1978-05-01

A sophisticated nonlinear multiparameter fitting program was used to produce a best fit calibration curve for the response of an x-ray fluorescence analyzer to uranium nitrate, freeze dried, 0.2% accurate, gravimetric standards. The program is based on unconstrained minimization subroutine, VA02A. The program considers the mass values of the gravimetric standards as parameters to be fit along with the normal calibration curve parameters. The fitting procedure weights with the system errors and the mass errors in a consistent way. The resulting best fit calibration curve parameters reflect the fact that the masses of the standard samples are measured quantities withmore » a known error. Error estimates for the calibration curve parameters can be obtained from the curvature of the ''Chi-Squared Matrix'' or from error relaxation techniques. It was shown that nondispersive XRFA of 0.1 to 1 mg freeze-dried UNO/sub 3/ can have an accuracy of 0.2% in 1000 s.« less

Nonlinear method for including the mass uncertainty of standards and the system measurement errors in the fitting of calibration curves

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

Pickles, W.L.; McClure, J.W.; Howell, R.H.

1978-01-01

A sophisticated non-linear multiparameter fitting program has been used to produce a best fit calibration curve for the response of an x-ray fluorescence analyzer to uranium nitrate, freeze dried, 0.2% accurate, gravimetric standards. The program is based on unconstrained minimization subroutine, VA02A. The program considers the mass values of the gravimetric standards as parameters to be fit along with the normal calibration curve parameters. The fitting procedure weights with the system errors and the mass errors in a consistent way. The resulting best fit calibration curve parameters reflect the fact that the masses of the standard samples are measured quantitiesmore » with a known error. Error estimates for the calibration curve parameters can be obtined from the curvature of the Chi-Squared Matrix or from error relaxation techniques. It has been shown that non-dispersive x-ray fluorescence analysis of 0.1 to 1 mg freeze-dried UNO/sub 3/ can have an accuracy of 0.2% in 1000 sec.« less

Effects of a 12-week program of Tai Chi exercise on the kidney disease quality of life and physical functioning of patients with end-stage renal disease on hemodialysis.

PubMed

Chang, Jo-Han; Koo, Malcolm; Wu, Sheng-Wen; Chen, Chiu-Yuan

2017-02-01

Previous studies have shown that exercise training in patients with end-stage renal disease could improve their physical functioning and quality of life. Nevertheless, few studies have evaluated the effects of Tai Chi exercise in patients on hemodialysis. To investigate the effects of a Tai Chi exercise intervention on the quality of life and physical functioning in end-stage renal disease patients on hemodialysis. A pre-post experimental design. Patients, aged 20 years or older, on hemodialysis recruited from the hemodialysis unit at a medical center in central Taiwan were assigned, based on their own preference, to either a control group (n=25) or an intervention group (n=21). A weekly one-hour short-form Yang style Tai Chi session for a total of 12 weeks. Physical functioning and Kidney Disease Quality of Life (KDQOL) at the baseline and at the end of the intervention. The least square means of repetition of sit-to-stand cycles in one minute (STS-60), 6-min walk test, and gait speed test were significantly improved in the intervention group. In addition, the least square means of the five different dimensions of the KDQOL were all significantly higher in the intervention group, except the SF-12 physical health score. Improvements in the kidney disease quality of life and physical functioning were observed in Taiwanese patients on hemodialysis with a 12-week Tai Chi exercise intervention. Copyright © 2016. Published by Elsevier Ltd.

[Depressive symptoms and its related factors among primary and middle school students in an urban-rural-integrated area of Chongqing].

PubMed

Li, Chen; Wang, Hong; Cao, Xingyuan; Gou, Min; Zhang, Zhuan

2013-09-01

To investigate the prevalence of depressive symptom and its influencing factors among primary and middle school students in urban-rural-integrated area of Chongqing. A total of 3 013 primary and middle school students from an urban-rural-integrated area of Chongqing were selected by using multistage stratified cluster sampling method in this study. The general information, physical activities and physical examination conditions were investigated. Meanwhile, the depress symptoms were assessed by using children's depression inventory (CDI) and the incidence of adolescence related events were evaluated by using pubertal development scale (PDS). Chi-square test was used to analyze the detection rate of depression symptoms among different population and Logistic regression was used to analyse the influencing factors of depressive symptoms among primary and middle school students. The detection rate of depressive symptoms was 20.1% (607/3013) totally, and it was gradually higher among the students with bad to good economic status (28.3%/18.4%/18.3%, chi2 = 28.415, P < 0.05). The students' detection rate of depression symptoms in different development level compared to companion by self image were 43.1%, 26.5%, 22.0% and 15.8% (chi2 = 79.621, P < 0.01). Among the senior school students, worse economic status, higher development level in self-evaluation, and no physical activities in a recent month (including physical training, aerobic exercise) were considered as the influencing factors of depressive symptoms. Focusing on the physical and mental health of growing children, establishing a good school environment and family environment, and strengthening physical activities will contribute to reducing the incidence of depressive symptoms.

Assessment of health literacy of municipal employees in Shemiranat, Iran.

PubMed

Solhi, Mahnaz; Jormand, Hanieh

2017-12-01

Health literacy is one of the major determinants of health promotion among individuals and within society. The present study is aimed to determine the health literacy status of office employees in Shemiranat using the native instruments of health literacy for Iranian adults (HELIA). The present descriptive-analytical cross-sectional study was done in 2016-17. It was conducted on 360 office employees in Shemiranat. The samples were selected using a multi-stage simple random sampling method. Data collection tools in this study included HELIA questionnaire. The data were imported into SPSS v.18 software and then analyzed using descriptive statistical indices (mean, SD, number, and percentage) and inferential statistics (Chi-square, Pearson's correlation coefficient, Spearman's correlation coefficient, and Kruskal-Wallis test). Written informed consent was obtained from the employees participating in the study and they were assured about confidentiality. Also, they were informed that participation was voluntary. The mean and standard deviation of the total health literacy score among the studied individuals was 125.99±16.01. The mean score of health literacy in the areas of reading (15.36±2.89) and evaluation (5.01±2.8) among the studied individuals was lower than other dimensions of health literacy. Based on the Chi-square test, there was a statistically significant relationship between health literacy and education level, occupational rank, work place, and work experience (p=0.0001 in all the cases). The individuals with medium and good levels of health literacy acquired most of their health-related information through the Internet, friends, relatives, physicians, and health staff. Health literacy status was not sufficient among the studied staff. Thus, it is recommended to perform promotional interventions in order to improve the health literacy status and its dimensions among these staff.

Evaluating Mesorectal Lymph Nodes in Rectal Cancer Before and After Neoadjuvant Chemoradiation Using Thin-Section T2-Weighted Magnetic Resonance Imaging

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

Koh, Dow-Mu; Chau, Ian; Tait, Diana

2008-06-01

Purpose: To apply thin-section T2-weighted magnetic resoance imaging (MRI) to evaluate the number, size, distribution, and morphology of benign and malignant mesorectal lymph nodes before and after chemoradiation treatment compared with histopathologic findings. Methods and Materials: Twenty-five patients with poor-risk adenocarcinoma of the rectum treated with neoadjuvant chemoradiation were evaluated prospectively. Thin-section T2-weighted MR images obtained before and after chemoradiation treatment were independently reviewed in consensus by 2 expert radiologists to determine the tumor stage, nodal size, nodal distribution, and nodal stage. Total mesorectal excision surgery after chemoradiation allowed MR nodal stage to be compared with histopathology using {kappa} statistics.more » Nodal downstaging was compared using the Chi-square test. Results: Before chemoradiation, 152 mesorectal nodes were visible (mean, 6.2 mm; 100 benign, 52 malignant) and 4 of 52 malignant nodes were in contact with the mesorectal fascia. The nodal staging was 7/25 N0, 10/25 N1, and 7/25 N2. After chemoradiation, only 29 nodes (mean, 4.1 mm; 24 benign, 5 malignant) were visible, and none were in contact with the mesorectal fascia. Nodal downstaging was observed: 20/25 N0 and 5/25 N1 (p < 0.01, Chi-square test). There was good agreement between MRI and pathologic T-staging ({kappa} = 0.64) and N-staging ({kappa} = 0.65) after chemoradiation. Conclusions: Neoadjuvant chemoradiation treatment resulted in a decrease in size and number of malignant- and benign-appearing mesorectal nodes on MRI. Nodal downstaging and nodal regression from the mesorectal fascia were observed after treatment. MRI is a useful tool for assessing nodal response to neoadjuvant treatment.« less

Patterns of Library Use by Undergraduate Students in a Chilean University

ERIC Educational Resources Information Center

Jara, Magdalena; Clasing, Paula; Gonzalez, Carlos; Montenegro, Maximiliano; Kelly, Nick; Alarcón, Rosa; Sandoval, Augusto; Saurina, Elvira

2017-01-01

This paper explores the patterns of use of print materials and digital resources in an undergraduate library in a Chilean university, by the students' discipline and year of study. A quantitative analysis was carried out, including descriptive analysis of contingency tables, chi-squared tests, t-tests, and multiple linear regressions. The results…

A poverty-related quality of life questionnaire can help to detect health inequalities in emergency departments.

PubMed

Boyer, Laurent; Baumstarck, Karine; Iordanova, Teodora; Fernandez, Jessica; Jean, Philippe; Auquier, Pascal

2014-03-01

This study aimed to develop a self-administered, multidimensional, poverty-related quality of life (PQoL) questionnaire for individuals seeking care in emergency departments (EDs): the PQoL-17. The development of the PQoL was undertaken in three steps: item generation, item reduction, and validation. The content of the PQoL was derived from 80 interviews with patients seeking care in EDs. Using item response and classical test theories, item reduction was performed in 3 EDs on 300 patients and validation was completed in 10 EDs on 619 patients. The PQoL contains 17 items describing seven dimensions (self-esteem/vitality, psychological well-being, relationships with family, relationships with friends, autonomy, physical well-being/access to care, and future perception). The seven-factor structure accounted for 75.1% of the total variance. This model showed a good fit (indices from the LISREL model: root mean square error of approximation, 0.055; comparative fit index, 0.97; general fit index, 0.96; standardized root mean square residual, 0.058). Each item achieved the 0.40 standard for item internal consistency, and Cronbach α coefficients were >0.70. Significant associations with socioeconomic and clinical indicators showed good discriminant and external validity. Infit statistics ranged from 0.82 to 1.16. The PQoL-17 presents satisfactory psychometric properties and can be completed quickly, thereby fulfilling the goal of brevity sought in EDs. Copyright © 2014 Elsevier Inc. All rights reserved.

Perspectives of Teachers Regarding Inclusive Education in Ghana

ERIC Educational Resources Information Center

Deku, Prosper; Vanderpuye, Irene

2017-01-01

The study explored teachers' perspectives on the curriculum, the physical environment and their preparation for the inclusive education programme. Data was collected using questionnaires. A sample of 120 teachers from schools identified as inclusive was used for the study. The t-test of independent samples and chi-square test were used to analyse…

Evaluating the performance of the Lee-Carter method and its variants in modelling and forecasting Malaysian mortality

NASA Astrophysics Data System (ADS)

Zakiyatussariroh, W. H. Wan; Said, Z. Mohammad; Norazan, M. R.

2014-12-01

This study investigated the performance of the Lee-Carter (LC) method and it variants in modeling and forecasting Malaysia mortality. These include the original LC, the Lee-Miller (LM) variant and the Booth-Maindonald-Smith (BMS) variant. These methods were evaluated using Malaysia's mortality data which was measured based on age specific death rates (ASDR) for 1971 to 2009 for overall population while those for 1980-2009 were used in separate models for male and female population. The performance of the variants has been examined in term of the goodness of fit of the models and forecasting accuracy. Comparison was made based on several criteria namely, mean square error (MSE), root mean square error (RMSE), mean absolute deviation (MAD) and mean absolute percentage error (MAPE). The results indicate that BMS method was outperformed in in-sample fitting for overall population and when the models were fitted separately for male and female population. However, in the case of out-sample forecast accuracy, BMS method only best when the data were fitted to overall population. When the data were fitted separately for male and female, LCnone performed better for male population and LM method is good for female population.

Association between socioeconomic deprivation and colorectal cancer screening outcomes: Low uptake rates among the most and least deprived people

PubMed Central

Auge, Josep M.; Sala, Maria; Román, Marta; Castells, Antoni; Macià, Francesc; Comas, Mercè; Guiriguet, Carolina; Bessa, Xavier; Castells, Xavier

2017-01-01

Background Screening with faecal occult blood tests reduces colorectal cancer-related mortality; however, age, sex and socioeconomic factors affect screening outcomes and could lead to unequal mortality benefits. The aim of this study was to describe the main outcomes of the population-based Barcelona colorectal cancer screening programme (BCRCSP) by deprivation. Methods Retrospective study of the eligible population of the first round of the BCRCSP. Participants’ postal addresses were linked with the MEDEA database to obtain the deprivation quintiles (Dq). Chi-squared tests were used to compare proportions across variables and logistic regression was used to estimate the adjusted effects of age, sex and deprivation on uptake, FIT positivity, colonoscopy adherence and advanced neoplasia detection rate. Results Overall uptake was 44.7%, higher in Dq2, 3 and 4 (OR 1.251, 1.250 and 1.276, respectively) than in the least deprived quintile (Dq 1), and lowest in Dq5 (OR 0.84). Faecal immunochemical test (FIT) positivity and the percentage of people with detectable faecal haemoglobin below the positivity threshold increased with deprivation. The advanced neoplasia detection rate was highest in Dq4. Conclusion Unlike most regions where inequalities are graded along the socioeconomic continuum, inequalities in the uptake of colorectal cancer screening in Spain seem to be concentrated first in the most disadvantaged group and second in the least deprived group. The correlation of deprivation with FIT-positivity and faecal haemoglobin below the positivity threshold is worrying due to its association with colorectal cancer and overall mortality. PMID:28622365

Outcome expectations for exercise scale: utility and psychometrics.

PubMed

Resnick, B; Zimmerman, S I; Orwig, D; Furstenberg, A L; Magaziner, J

2000-11-01

The purpose of this study was to develop a measure of outcome expectations for exercise specifically for the older adult (The Outcome Expectations for Exercise [OEE] Scale), and to test the reliability and validity of this measure in a sample of older individuals. This scale was developed based on Bandura's theory of self-efficacy and the work of prior researchers in the development of measures of outcome expectations. The OEE scale, which was completed during a face-to-face interview, was tested in a sample of 175 residents in a continuing care retirement community. There was support for the internal consistency of the OEE scale (alpha coefficient of .89), and some support for reliability based on a structural equation modeling approach that used R2 estimates, although less than half of these were greater than 0.5. There was evidence of validity of the measure based on: (a) a confirmatory factor analysis in which the model fit the data (normed fit index [NFI] = .99, root mean square error of approximation [RMSEA] - .07, chi2/df = 2.8); (b) support for the hypothesis that those who exercised regularly had higher OEE scores than those who did not (F = 31.3, p < .05, eta squared = .15); and (c) a statistically significant relationship between outcome expectations and self-efficacy expectations (r = .66). This study provides some initial support for the reliability and validity of the OEE scale. Outcome expectations for exercise were related to exercise behavior in the older adult, and the OEE scale can help identify older adults with low outcome expectations for exercise. Interventions can then be implemented to help these individuals strengthen their outcome expectations, which may subsequently improve exercise behavior.

Exercise training in adults with Pompe disease: the effects on pain, fatigue, and functioning.

PubMed

Favejee, Marein M; van den Berg, Linda E M; Kruijshaar, Michelle E; Wens, Stephan C A; Praet, Stephan F E; Pim Pijnappel, W W M; van Doorn, Pieter A; Bussmann, Johannes B J; van der Ploeg, Ans T

2015-05-01

To assess if a 12-week exercise intervention to improve aerobic fitness, muscle strength, and core stability also had an impact on fatigue, pain, activity, and participation in adults with Pompe disease, an inherited neuromuscular disorder. Open-label trial. Change was assessed by the chi-square test and Wilcoxon signed-rank test. Physiotherapy practices. Mildly affected adult patients with Pompe disease who were not dependent on ventilators and/or walking devices and were receiving enzyme replacement therapy. Patients participated in a 12-week exercise program, which included 36 sessions of standardized aerobic, resistance, and core stability exercises. Before and after the training program we evaluated fatigue (Fatigue Severity Scale), pain (yes/no), motor function (Quantitative Muscle Function Test, Rasch-built Pompe-specific Activity Scale), amount of physical activity (activity monitor), and health status (Medical Outcomes Study 36-Item Short-Form Health Survey). Of the 25 patients enrolled, 23 completed the program. At the end of the program, levels of fatigue (median, 5.33 to 4.78, P=.01) and pain (56.5% to 21.7%, P=.04) improved. The quality of motor function and the amount of physical activity patients engaged in did not change. Changes in pain and fatigue were not related to improvements in aerobic fitness or muscle strength. This study in mildly affected adult patients with Pompe disease suggests that a combined training program aiming to increase aerobic fitness, muscle strength, and core stability also leads to improvements in fatigue and pain. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Perceptions and receptivity of non-spousal family support: A mixed methods study of psychological distress among older, church-going African American men

PubMed Central

Watkins, Daphne C.; Wharton, Tracy; Mitchell, Jamie A.; Matusko, Niki; Kales, Helen

2016-01-01

The purpose of this study was to explore the role of non-spousal family support on mental health among older, church-going African American men. The mixed methods objective was to employ a design that used existing qualitative and quantitative data to explore the interpretive context within which social and cultural experiences occur. Qualitative data (n=21) were used to build a conceptual model that was tested using quantitative data (n= 401). Confirmatory factor analysis indicated an inverse association between non-spousal family support and distress. The comparative fit index, Tucker-Lewis fit index, and root mean square error of approximation indicated good model fit. This study offers unique methodological approaches to using existing, complementary data sources to understand the health of African American men. PMID:28943829

Revisiting galactic black hole binary GX 339-4 by using 2007 – 2014 Swift XRT observations

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

Azizi, Febrie Ahmad; Vierdayanti, Kiki; Putra, Mahasena

2015-09-30

This work aims to study the X-ray properties of the galactic black hole binary GX 339-4. Focus of the study is on exploration of data from Swift-XRT in exclusively photon-counting mode. We use data from 2007 up to August 2014, which contain about 40 pointing observations with level 1 data. The flux of GX 339-4 varies in a factor of 100 during this period of observations. For the purpose of this work, we also try to develop a system to conduct standard SWIFT XRT data reduction automatically, in order to greatly reduce time when working with data bulk, which producesmore » images, lightcurves as well as spectra. We also develop another system to conduct fitting of bulk spectral data with a two-component model, disk blackbody and power-law. The fitting results show that no data have a reduced chi-squared > 2. The fraction of the disk to total flux and the power-law to total flux range from 0.00389 – 0.994 and 0.00605 – 0.996, respectively. From the analysis of the disk component, we obtain the value of the innermost disk radius that does not show any large scale truncation which is in a good agreement with a previous study that used 2007 – 2011 Swift-XRT data, indicating that the systems we developed work properly.« less

Impact of physical fitness and body composition on injury risk among active young adults: A study of Army trainees.

PubMed

Jones, Bruce H; Hauret, Keith G; Dye, Shamola K; Hauschild, Veronique D; Rossi, Stephen P; Richardson, Melissa D; Friedl, Karl E

2017-11-01

To determine the combined effects of physical fitness and body composition on risk of training-related musculoskeletal injuries among Army trainees. Retrospective cohort study. Rosters of soldiers entering Army basic combat training (BCT) from 2010 to 2012 were linked with data from multiple sources for age, sex, physical fitness (heights, weights (mass), body mass index (BMI), 2 mile run times, push-ups), and medical injury diagnoses. Analyses included descriptive means and standard deviations, comparative t-tests, risks of injury, and relative risks (RR) and 95% confidence intervals (CI). Fitness and BMI were divided into quintiles (groups of 20%) and stratified for chi-square (χ 2 ) comparisons and to determine trends. Data were obtained for 143,398 men and 41,727 women. As run times became slower, injury risks increased steadily (men=9.8-24.3%, women=26.5-56.0%; χ 2 trends (p<0.00001)). For both genders, the relationship of BMI to injury risk was bimodal, with the lowest risk in the average BMI group (middle quintile). Injury risks were highest in the slowest groups with lowest BMIs (male trainees=26.5%; female trainees=63.1%). Compared to lowest risk group (average BMI with fastest run-times), RRs were significant (male trainees=8.5%; RR 3.1, CI: 2.8-3.4; female trainees=24.6%; RR 2.6, CI: 2.3-2.8). Trainees with the lowest BMIs exhibited highest injury risks for both genders and across all fitness levels. While the most aerobically fit Army trainees experience lower risk of training-related injury, at any given aerobic fitness level those with the lowest BMIs are at highest risk. This has implications for recruitment and retention fitness standards. Copyright © 2017. Published by Elsevier Ltd.

Uncertainty in least-squares fits to the thermal noise spectra of nanomechanical resonators with applications to the atomic force microscope.

PubMed

Sader, John E; Yousefi, Morteza; Friend, James R

2014-02-01

Thermal noise spectra of nanomechanical resonators are used widely to characterize their physical properties. These spectra typically exhibit a Lorentzian response, with additional white noise due to extraneous processes. Least-squares fits of these measurements enable extraction of key parameters of the resonator, including its resonant frequency, quality factor, and stiffness. Here, we present general formulas for the uncertainties in these fit parameters due to sampling noise inherent in all thermal noise spectra. Good agreement with Monte Carlo simulation of synthetic data and measurements of an Atomic Force Microscope (AFM) cantilever is demonstrated. These formulas enable robust interpretation of thermal noise spectra measurements commonly performed in the AFM and adaptive control of fitting procedures with specified tolerances.

Uncertainty in least-squares fits to the thermal noise spectra of nanomechanical resonators with applications to the atomic force microscope

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

Sader, John E., E-mail: jsader@unimelb.edu.au; Yousefi, Morteza; Friend, James R.

2014-02-15

Thermal noise spectra of nanomechanical resonators are used widely to characterize their physical properties. These spectra typically exhibit a Lorentzian response, with additional white noise due to extraneous processes. Least-squares fits of these measurements enable extraction of key parameters of the resonator, including its resonant frequency, quality factor, and stiffness. Here, we present general formulas for the uncertainties in these fit parameters due to sampling noise inherent in all thermal noise spectra. Good agreement with Monte Carlo simulation of synthetic data and measurements of an Atomic Force Microscope (AFM) cantilever is demonstrated. These formulas enable robust interpretation of thermal noisemore » spectra measurements commonly performed in the AFM and adaptive control of fitting procedures with specified tolerances.« less

Prevalence of alveolar bone loss in healthy children treated at private pediatric dentistry clinics

PubMed Central

GUIMARÃES, Maria do Carmo Machado; de ARAÚJO, Valéria Martins; AVENA, Márcia Raquel; DUARTE, Daniel Rocha da Silva; FREITAS, Francisco Valter

2010-01-01

Objectives The purpose of this study was to evaluate the prevalence of alveolar bone loss (BL) in healthy children treated at private pediatric dentistry clinics in Brasília, Brazil. Material and Methods The research included 7,436 sites present in 885 radiographs from 450 children. The BL prevalence was estimated by measuring the distance from the cementoenamel junction (CEJ) to alveolar bone crest (ABC). Data were divided in groups: (I) No BL: distance from CEJ to ABC is ≤2 mm; (II) questionable BL (QBL): distance from CEJ to ABC is >2 and <3 mm; (III) definite BL (DBL): distance from CEJ to ABC ≥3 mm. Data were treated by the chi-square nonparametric test and Fisher's exact test (p<0.05). Results Among males, 89.31% were classified in group I, 9.82% were classified in group II and 0.85% in group III. Among females, 93.05%, 6.48% and 0.46% patients were classified in Group I, II and III, respectively. The differences between genders were not statistically significant (Chi-square test, p = 0.375). Group composition according to patients’ age showed that 91.11% of individuals were classified as group I, 8.22% in group II and 0.67% in group III. The differences among the age ranges were not statistically significant (Chi-square test, p = 0.418). The mesial and distal sites showed a higher prevalence of BL in the jaw, QBL (89.80%) and DBL (79.40%), and no significant difference was observed in the distribution of QBL (Fisher’s exact test p = 0.311) and DBL (Fisher’s exact test p = 0.672) in the dental arches. The distal sites exhibited higher prevalence of both QBL (77.56%) and DBL (58.82%). Conclusions The periodontal status of children should never be underestimated because BL occurs even in healthy populations, although in a lower frequency. PMID:20857009

Prevalence of alveolar bone loss in healthy children treated at private pediatric dentistry clinics.

PubMed

Guimarães, Maria do Carmo Machado; de Araújo, Valéria Martins; Avena, Márcia Raquel; Duarte, Daniel Rocha da Silva; Freitas, Francisco Valter

2010-01-01

The purpose of this study was to evaluate the prevalence of alveolar bone loss (BL) in healthy children treated at private pediatric dentistry clinics in Brasília, Brazil. The research included 7,436 sites present in 885 radiographs from 450 children. The BL prevalence was estimated by measuring the distance from the cementoenamel junction (CEJ) to alveolar bone crest (ABC). Data were divided in groups: (I) No BL: distance from CEJ to ABC is <2 mm; (II) questionable BL (QBL): distance from CEJ to ABC is >2 and <3 mm; (III) definite BL (DBL): distance from CEJ to ABC >3 mm. Data were treated by the chi-square nonparametric test and Fisher's exact test (p<0.05). Among males, 89.31% were classified in group I, 9.82% were classified in group II and 0.85% in group III. Among females, 93.05%, 6.48% and 0.46% patients were classified in Group I, II and III, respectively. The differences between genders were not statistically significant (Chi-square test, p = 0.375). Group composition according to patients' age showed that 91.11% of individuals were classified as group I, 8.22% in group II and 0.67% in group III. The differences among the age ranges were not statistically significant (Chi-square test, p = 0.418). The mesial and distal sites showed a higher prevalence of BL in the jaw, QBL (89.80%) and DBL (79.40%), and no significant difference was observed in the distribution of QBL (Fisher's exact test p = 0.311) and DBL (Fisher's exact test p = 0.672) in the dental arches. The distal sites exhibited higher prevalence of both QBL (77.56%) and DBL (58.82%). The periodontal status of children should never be underestimated because BL occurs even in healthy populations, although in a lower frequency.

Foveal Curvature and Asymmetry Assessed Using Optical Coherence Tomography.

PubMed

VanNasdale, Dean A; Eilerman, Amanda; Zimmerman, Aaron; Lai, Nicky; Ramsey, Keith; Sinnott, Loraine T

2017-06-01

The aims of this study were to use cross-sectional optical coherence tomography imaging and custom curve fitting software to evaluate and model the foveal curvature as a spherical surface and to compare the radius of curvature in the horizontal and vertical meridians and test the sensitivity of this technique to anticipated meridional differences. Six 30-degree foveal-centered radial optical coherence tomography cross-section scans were acquired in the right eye of 20 clinically normal subjects. Cross sections were manually segmented, and custom curve fitting software was used to determine foveal pit radius of curvature using the central 500, 1000, and 1500 μm of the foveal contour. Radius of curvature was compared across different fitting distances. Root mean square error was used to determine goodness of fit. The radius of curvature was compared between the horizontal and vertical meridians for each fitting distance. There radius of curvature was significantly different when comparing each of the three fitting distances (P < .01 for each comparison). The average radii of curvature were 970 μm (95% confidence interval [CI], 913 to 1028 μm), 1386 μm (95% CI, 1339 to 1439 μm), and 2121 μm (95% CI, 2066 to 2183) for the 500-, 1000-, and 1500-μm fitting distances, respectively. Root mean square error was also significantly different when comparing each fitting distance (P < .01 for each comparison). The average root mean square errors were 2.48 μm (95% CI, 2.41 to 2.53 μm), 6.22 μm (95% CI, 5.77 to 6.60 μm), and 13.82 μm (95% CI, 12.93 to 14.58 μm) for the 500-, 1000-, and 1500-μm fitting distances, respectively. The radius of curvature between the horizontal and vertical meridian radii was statistically different only in the 1000- and 1500-μm fitting distances (P < .01 for each), with the horizontal meridian being flatter than the vertical. The foveal contour can be modeled as a sphere with low curve fitting error over a limited distance and capable of detecting subtle foveal contour differences between meridians.

Injury Rate and Patterns Among CrossFit Athletes.

PubMed

Weisenthal, Benjamin M; Beck, Christopher A; Maloney, Michael D; DeHaven, Kenneth E; Giordano, Brian D

2014-04-01

CrossFit is a type of competitive exercise program that has gained widespread recognition. To date, there have been no studies that have formally examined injury rates among CrossFit participants or factors that may contribute to injury rates. To establish an injury rate among CrossFit participants and to identify trends and associations between injury rates and demographic categories, gym characteristics, and athletic abilities among CrossFit participants. Descriptive epidemiology study. A survey was conducted, based on validated epidemiologic injury surveillance methods, to identify patterns of injury among CrossFit participants. It was sent to CrossFit gyms in Rochester, New York; New York City, New York; and Philadelphia, Pennsylvania, and made available via a posting on the main CrossFit website. Participants were encouraged to distribute it further, and as such, there were responses from a wide geographical location. Inclusion criteria included participating in CrossFit training at a CrossFit gym in the United States. Data were collected from October 2012 to February 2013. Data analysis was performed using Fisher exact tests and chi-square tests. A total of 486 CrossFit participants completed the survey, and 386 met the inclusion criteria. The overall injury rate was determined to be 19.4% (75/386). Males (53/231) were injured more frequently than females (21/150; P = .03). Across all exercises, injury rates were significantly different (P < .001), with shoulder (21/84), low back (12/84), and knee (11/84) being the most commonly injured overall. The shoulder was most commonly injured in gymnastic movements, and the low back was most commonly injured in power lifting movements. Most participants did not report prior injury (72/89; P < .001) or discomfort in the area (58/88; P < .001). Last, the injury rate was significantly decreased with trainer involvement (P = .028). The injury rate in CrossFit was approximately 20%. Males were more likely to sustain an injury than females. The involvement of trainers in coaching participants on their form and guiding them through the workout correlates with a decreased injury rate. The shoulder and lower back were the most commonly injured in gymnastic and power lifting movements, respectively. Participants reported primarily acute and fairly mild injuries.

A SIGNIFICANCE TEST FOR THE LASSO1

PubMed Central

Lockhart, Richard; Taylor, Jonathan; Tibshirani, Ryan J.; Tibshirani, Robert

2014-01-01

In the sparse linear regression setting, we consider testing the significance of the predictor variable that enters the current lasso model, in the sequence of models visited along the lasso solution path. We propose a simple test statistic based on lasso fitted values, called the covariance test statistic, and show that when the true model is linear, this statistic has an Exp(1) asymptotic distribution under the null hypothesis (the null being that all truly active variables are contained in the current lasso model). Our proof of this result for the special case of the first predictor to enter the model (i.e., testing for a single significant predictor variable against the global null) requires only weak assumptions on the predictor matrix X. On the other hand, our proof for a general step in the lasso path places further technical assumptions on X and the generative model, but still allows for the important high-dimensional case p > n, and does not necessarily require that the current lasso model achieves perfect recovery of the truly active variables. Of course, for testing the significance of an additional variable between two nested linear models, one typically uses the chi-squared test, comparing the drop in residual sum of squares (RSS) to a χ12 distribution. But when this additional variable is not fixed, and has been chosen adaptively or greedily, this test is no longer appropriate: adaptivity makes the drop in RSS stochastically much larger than χ12 under the null hypothesis. Our analysis explicitly accounts for adaptivity, as it must, since the lasso builds an adaptive sequence of linear models as the tuning parameter λ decreases. In this analysis, shrinkage plays a key role: though additional variables are chosen adaptively, the coefficients of lasso active variables are shrunken due to the l1 penalty. Therefore, the test statistic (which is based on lasso fitted values) is in a sense balanced by these two opposing properties—adaptivity and shrinkage—and its null distribution is tractable and asymptotically Exp(1). PMID:25574062

Scale construction utilising the Rasch unidimensional measurement model: A measurement of adolescent attitudes towards abortion.

PubMed

Hendriks, Jacqueline; Fyfe, Sue; Styles, Irene; Skinner, S Rachel; Merriman, Gareth

2012-01-01

Measurement scales seeking to quantify latent traits like attitudes, are often developed using traditional psychometric approaches. Application of the Rasch unidimensional measurement model may complement or replace these techniques, as the model can be used to construct scales and check their psychometric properties. If data fit the model, then a scale with invariant measurement properties, including interval-level scores, will have been developed. This paper highlights the unique properties of the Rasch model. Items developed to measure adolescent attitudes towards abortion are used to exemplify the process. Ten attitude and intention items relating to abortion were answered by 406 adolescents aged 12 to 19 years, as part of the "Teen Relationships Study". The sampling framework captured a range of sexual and pregnancy experiences. Items were assessed for fit to the Rasch model including checks for Differential Item Functioning (DIF) by gender, sexual experience or pregnancy experience. Rasch analysis of the original dataset initially demonstrated that some items did not fit the model. Rescoring of one item (B5) and removal of another (L31) resulted in fit, as shown by a non-significant item-trait interaction total chi-square and a mean log residual fit statistic for items of -0.05 (SD=1.43). No DIF existed for the revised scale. However, items did not distinguish as well amongst persons with the most intense attitudes as they did for other persons. A person separation index of 0.82 indicated good reliability. Application of the Rasch model produced a valid and reliable scale measuring adolescent attitudes towards abortion, with stable measurement properties. The Rasch process provided an extensive range of diagnostic information concerning item and person fit, enabling changes to be made to scale items. This example shows the value of the Rasch model in developing scales for both social science and health disciplines.

An automated approach to Litchfield and Wilcoxon's evaluation of dose–effect experiments using the R package LW1949

USGS Publications Warehouse

Adams, Jean V.; Slaght, Karen; Boogaard, Michael A.

2016-01-01

The authors developed a package, LW1949, for use with the statistical software R to automatically carry out the manual steps of Litchfield and Wilcoxon's method of evaluating dose–effect experiments. The LW1949 package consistently finds the best fitting dose–effect relation by minimizing the chi-squared statistic of the observed and expected number of affected individuals and substantially speeds up the line-fitting process and other calculations that Litchfield and Wilcoxon originally carried out by hand. Environ Toxicol Chem 2016;9999:1–4. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.

Effect of a checklist on advanced trauma life support workflow deviations during trauma resuscitations without pre-arrival notification.

PubMed

Kelleher, Deirdre C; Jagadeesh Chandra Bose, R P; Waterhouse, Lauren J; Carter, Elizabeth A; Burd, Randall S

2014-03-01

Trauma resuscitations without pre-arrival notification are often initially chaotic, which can potentially compromise patient care. We hypothesized that trauma resuscitations without pre-arrival notification are performed with more variable adherence to ATLS protocol and that implementation of a checklist would improve performance. We analyzed event logs of trauma resuscitations from two 4-month periods before (n = 222) and after (n = 215) checklist implementation. Using process mining techniques, individual resuscitations were compared with an ideal workflow model of 6 ATLS primary survey tasks performed by the bedside evaluator and given model fitness scores (range 0 to 1). Mean fitness scores and frequency of conformance (fitness = 1) were compared (using Student's t-test or chi-square test, as appropriate) for activations with and without notification both before and after checklist implementation. Multivariable linear regression, controlling for patient and resuscitation characteristics, was also performed to assess the association between pre-arrival notification and model fitness before and after checklist implementation. Fifty-five (12.6%) resuscitations lacked pre-arrival notification (23 pre-implementation and 32 post-implementation; p = 0.15). Before checklist implementation, resuscitations without notification had lower fitness (0.80 vs 0.90; p < 0.001) and conformance (26.1% vs 50.8%; p = 0.03) than those with notification. After checklist implementation, the fitness (0.80 vs 0.91; p = 0.007) and conformance (26.1% vs 59.4%; p = 0.01) improved for resuscitations without notification, but still remained lower than activations with notification. In multivariable analysis, activations without notification had lower fitness both before (b = -0.11, p < 0.001) and after checklist implementation (b = -0.04, p = 0.02). Trauma resuscitations without pre-arrival notification are associated with a decreased adherence to key components of the ATLS primary survey protocol. The addition of a checklist improves protocol adherence and reduces the effect of notification on task performance. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

The Malay Version of the Perceived Stress Scale (PSS)-10 is a Reliable and Valid Measure for Stress among Nurses in Malaysia.

PubMed

Sandhu, Sukhvinder Singh; Ismail, Noor Hassim; Rampal, Krishna Gopal

2015-11-01

The Perceived Stress Scale-10 (PSS-10) is widely used to assess stress perception. The aim of this study was to translate the original PSS-10 into Malay and assess the reliability and validity of the Malay version among nurses. The Malay version of the PSS-10 was distributed among 229 nurses from four government hospitals in Selangor State. Test-retest reliability and concurrent validity was conducted with 25 nurses with the Malay version of the Depression Anxiety Stress Scales (DASS) 21. Cronbach's alpha, confirmatory factor analysis (CFA), intraclass correlation coefficient and Pearson's r correlation coefficient were used to determine the psychometric properties of the Malay PSS-10. Two factor components were yielded through exploratory factor analysis with eigenvalues of 3.37 and 2.10, respectively. Both of the factors accounted for 54.6% of the variance. CFA yielded a two-factor structure with satisfactory goodness-of-fit indices [x 2 /df = 2.43; comparative fit index (CFI) = 0.92, goodness-of-fit Index (GFI) = 0.94; standardised root mean square residual (SRMR) = 0.07 and root mean square error of approximation (RMSEA) = 0.08 (90% CI = 0.07-0.09)]. The Cronbach's alpha coefficient for the total items was 0.63 (0.82 for factor 1 and 0.72 for factor 2). The intraclass correlation coefficient (ICC) was 0.81 (95% CI: 0.62-0.91) for test-retest reliability testing after seven days. The total score and the negative component of the PSS-10 correlated significantly with the stress component of the DASS-21: (r = 0.61, P < 0.001) and (r = 0.56, P < 0.004), respectively. The Malay version of the PSS-10 demonstrated a satisfactory level of validity and reliability to assess stress perception. Therefore, this questionnaire is valid in assessing stress perception among nurses in Malaysia.

Double asymptotics for the chi-square statistic.

PubMed

Rempała, Grzegorz A; Wesołowski, Jacek

2016-12-01

Consider distributional limit of the Pearson chi-square statistic when the number of classes m n increases with the sample size n and [Formula: see text]. Under mild moment conditions, the limit is Gaussian for λ = ∞, Poisson for finite λ > 0, and degenerate for λ = 0.

What are the most important factors determining different vegetation types in the Chapada Diamantina, Brazil?

PubMed

Neves, S P S; Funch, R; Conceição, A A; Miranda, L A P; Funch, L S

2016-06-01

A transect was used to examine the environmental and biological descriptors of a compact vegetation mosaic in the Chapada Diamantina in northeastern Brazil, including the floristic composition, spectrum of plant life forms, rainfall, and soil properties that defined areas of cerrado (Brazilian savanna), caatinga (seasonally dry tropical forest thorny, deciduous shrub/arboreal vegetation) and cerrado-caatinga transition vegetation. The floristic survey was made monthly from April/2009 to March/2012. A dendrogram of similarity was generated using the Jaccard Index based on a matrix of the species that occurred in at least two of the vegetation types examined. The proportions of life forms in each vegetation type were compared using the chi-square test. Composite soil samples were analyzed by simple variance (ANOVA) to examine relationships between soil parameters of each vegetation type and the transition area. The monthly precipitation levels in each vegetation type were measured and compared using the chi-square test. A total of 323 species of angiosperms were collected distributed in 193 genera and 54 families. The dendrogram demonstrated strong difference between the floristic compositions of the cerrado and caatinga, sharing 2% similarity. The chi-square test did not demonstrate any significant statistical differences between the monthly values of recorded rainfall. The organic matter and clay contents of the soilsin the caatinga increased while sand decreased, and the proportions of therophyte, hemicryptophyte, and chamaephyte life forms decreased and phanerophytes increased. We can therefore conclude that the floristic composition and the spectrum of life forms combined to define the cerrado and caatinga vegetation along the transect examined, with soil being the principal conditioning factor determining the different vegetation types, independent of precipitation levels.

Evaluation of the efficacy of rotary vs. hand files in root canal preparation of primary teeth in vitro using CBCT.

PubMed

Musale, P K; Mujawar, S A V

2014-04-01

This in vitro study aimed to evaluate the efficacy of rotary ProFile, ProTaper, Hero Shaper and K-files in shaping ability, cleaning efficacy, preparation time and instrument distortion in primary molars. Sixty extracted primary mandibular second molars were divided into four equal groups: Group I K-file, Group II ProFile, Group III ProTaper file and Group IV Hero Shaper file. The shaping ability was determined by comparing pre- and post-instrumentation CBCT scans and data analysed with SPSS program using the Chi-square test. Cleaning efficacy was evaluated by the degree of India ink removal from the canal walls under stereomicroscopy. Instrumentation times were calculated for each tooth and instrument distortion was visually checked and duly noted. The cleaning efficacy and instrumentation time were determined using ANOVA with Tukey's correction. Instrument distortion was analysed using Chi-square test. The canal taper was significantly more conical for rotary files as compared to K-files with Chi-square test (p < 0.05). Cleaning efficacy of rotary files with average scores (Groups II- 0.68, III- 0.48 and IV- 0.58) was significantly better than K-files (Group I- 0.93) (p < 0.05). Mean instrumentation time with K-file (20.7 min) was significantly higher than rotary files (Groups II 8.9, III 5.6, and IV 8.1 min) (p < 0.05). Instrument distortion was observed in Group I (4.3%), while none of the rotary files were distorted. Rotary files prepared more conical canals in primary teeth than manual instruments. Reduced preparation time with rotary files enhances patient cooperation especially in young children.

On the Likelihood Ratio Test for the Number of Factors in Exploratory Factor Analysis

ERIC Educational Resources Information Center

Hayashi, Kentaro; Bentler, Peter M.; Yuan, Ke-Hai

2007-01-01

In the exploratory factor analysis, when the number of factors exceeds the true number of factors, the likelihood ratio test statistic no longer follows the chi-square distribution due to a problem of rank deficiency and nonidentifiability of model parameters. As a result, decisions regarding the number of factors may be incorrect. Several…

Educators' Understanding of the Mediation Role in the Classroom

ERIC Educational Resources Information Center

Ngidi, D. P.

2012-01-01

This study investigated educators' understanding of the mediation role in the classroom. A quantitative research approach was used in a survey of a sample of 261 participants. To this end, a questionnaire was used for collecting data. The Chi-square test was used to analyse data and to test the hypotheses of the study. The findings indicated that…

Construct and content validity of the Turkish Birth Satisfaction Scale - Revised (T-BSS-R).

PubMed

Göncü Serhatlıoğlu, Seda; Karahan, Nazan; Hollins Martin, Caroline J; Martin, Colin R

2018-07-01

The Birth Satisfaction Scale - Revised (BSS-R) is a valid and reliable scale designed to assess women's experiences of labour and childbirth. To assess factor structure, validity, and reliability of the Turkish Birth Satisfaction Scale - Revised (T-BSS-R) using data collected from a Turkish population. Istanbul Ministry of Health Zeynep Kamil Women's and Children's Training and Research Hospital. A convenience sample of healthy child-bearing women (n = 120) who had experienced a spontaneous vertex delivery at full term. A survey was conducted post backtranslating the T-BSS-R, with survey data analysed using confirmatory factor analysis. Factor modelling found three subscales embedded in the T-BSS-R, which indicated a good model fit, χ 2 = 44.67, CFI = .94; RMSEA = .057; SRMR = .075. A Chi-square value of 1.33 also indicated a good fit. Means for the T-BSS-R subdimensions (1) Stress Experienced (T-BSS-SE-R) = 6.86 ± 3.10, (2) Women's Attributes (T-BSS-WA-R) = 2.84 ± 1.89, (3) Quality of Care (T-BSS-QC-R) = 10.69 ± 3.19 and total scale = 20.39 ± 5.98. The Cronbach alpha coefficient for total scale = 0.71 and for subdimensions T-BSS-SE-R = 0.55, T-BSS-WA-R = 0.44 and T-BSS-QC-R = -0.74. Data analysis determined that the T-BSS-R is a valid and reliable instrument to measure birth satisfaction in a population of Turkish women. The T-BSS-R is available for use from c.hollinsmartin@napier.ac.uk .

Uranium, radium and thorium in soils with high-resolution gamma spectroscopy, MCNP-generated efficiencies, and VRF non-linear full-spectrum nuclide shape fitting

NASA Astrophysics Data System (ADS)

Metzger, Robert; Riper, Kenneth Van; Lasche, George

2017-09-01

A new method for analysis of uranium and radium in soils by gamma spectroscopy has been developed using VRF ("Visual RobFit") which, unlike traditional peak-search techniques, fits full-spectrum nuclide shapes with non-linear least-squares minimization of the chi-squared statistic. Gamma efficiency curves were developed for a 500 mL Marinelli beaker geometry as a function of soil density using MCNP. Collected spectra were then analyzed using the MCNP-generated efficiency curves and VRF to deconvolute the 90 keV peak complex of uranium and obtain 238U and 235U activities. 226Ra activity was determined either from the radon daughters if the equilibrium status is known, or directly from the deconvoluted 186 keV line. 228Ra values were determined from the 228Ac daughter activity. The method was validated by analysis of radium, thorium and uranium soil standards and by inter-comparison with other methods for radium in soils. The method allows for a rapid determination of whether a sample has been impacted by a man-made activity by comparison of the uranium and radium concentrations to those that would be expected from a natural equilibrium state.

Characteristics and Psychosocial Predictors of Adolescent Nonsuicidal Self-Injury in Residential Care

ERIC Educational Resources Information Center

Gallant, Jason; Snyder, Gregory S.; von der Embse, Nathaniel P.

2014-01-01

This study examined characteristics and biopsychosocial predictors of nonsuicidal self-injury in a sample (N = 753) of youth in residential care admitted between 2005 and 2010. To model the data, the authors used t-tests, chi-square tests, and multiple logistic regressions stratified by gender. Results suggested that 12% of youth engaged in…

DIF Detection Using Multiple-Group Categorical CFA with Minimum Free Baseline Approach

ERIC Educational Resources Information Center

Chang, Yu-Wei; Huang, Wei-Kang; Tsai, Rung-Ching

2015-01-01

The aim of this study is to assess the efficiency of using the multiple-group categorical confirmatory factor analysis (MCCFA) and the robust chi-square difference test in differential item functioning (DIF) detection for polytomous items under the minimum free baseline strategy. While testing for DIF items, despite the strong assumption that all…

Modeling The Atmosphere In The Era Of Big Data From Extremely Wide Field-Of-View Telescopes

NASA Astrophysics Data System (ADS)

Gonzalez Quiles, Junellie; Nordin, Jakob

2018-01-01

Surveys like the Sloan Digital Sky Survey (SDSS), Pan-STARRS and the Palomar Transient Factory Survey (PTF) receive large amounts of data, which need to be processed and calibrated in order to correct for various factors. One of the limiting factors in obtaining high quality data is the atmosphere, and it is therefore essential to find the appropriate calibration for the atmospheric extinction. It is to be expected that a physical atmospheric model, compared to a photometric calibration used currently by PTF, is more effective in calibrating for the atmospheric extinction due to its ability to account for rapid atmospheric fluctuation and objects of different colors. We focused on creating tools to model the atmospheric extinction for the upcoming Zwicky Transient Factory Survey (ZTF). In order to model the atmosphere, we created a program that combines input data and catalogue values, and efficiently handles them. Then, using PTF data and the SDSS catalogue, we created several models to fit the data, and tested the quality of the fits by chi-square minimization. This will allow us to optimize atmospheric extinction for the upcoming ZTF in the near future.

A comparison of the prognostic value of preoperative inflammation-based scores and TNM stage in patients with gastric cancer.

PubMed

Pan, Qun-Xiong; Su, Zi-Jian; Zhang, Jian-Hua; Wang, Chong-Ren; Ke, Shao-Ying

2015-01-01

People's Republic of China is one of the countries with the highest incidence of gastric cancer, accounting for 45% of all new gastric cancer cases in the world. Therefore, strong prognostic markers are critical for the diagnosis and survival of Chinese patients suffering from gastric cancer. Recent studies have begun to unravel the mechanisms linking the host inflammatory response to tumor growth, invasion and metastasis in gastric cancers. Based on this relationship between inflammation and cancer progression, several inflammation-based scores have been demonstrated to have prognostic value in many types of malignant solid tumors. To compare the prognostic value of inflammation-based prognostic scores and tumor node metastasis (TNM) stage in patients undergoing gastric cancer resection. The inflammation-based prognostic scores were calculated for 207 patients with gastric cancer who underwent surgery. Glasgow prognostic score (GPS), neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), prognostic nutritional index (PNI), and prognostic index (PI) were analyzed. Linear trend chi-square test, likelihood ratio chi-square test, and receiver operating characteristic were performed to compare the prognostic value of the selected scores and TNM stage. In univariate analysis, preoperative serum C-reactive protein (P<0.001), serum albumin (P<0.001), GPS (P<0.001), PLR (P=0.002), NLR (P<0.001), PI (P<0.001), PNI (P<0.001), and TNM stage (P<0.001) were significantly associated with both overall survival and disease-free survival of patients with gastric cancer. In multivariate analysis, GPS (P=0.024), NLR (P=0.012), PI (P=0.001), TNM stage (P<0.001), and degree of differentiation (P=0.002) were independent predictors of gastric cancer survival. GPS and TNM stage had a comparable prognostic value and higher linear trend chi-square value, likelihood ratio chi-square value, and larger area under the receiver operating characteristic curve as compared to other inflammation-based prognostic scores. The present study indicates that preoperative GPS and TNM stage are robust predictors of gastric cancer survival as compared to NLR, PLR, PI, and PNI in patients undergoing tumor resection.

A comparison of the prognostic value of preoperative inflammation-based scores and TNM stage in patients with gastric cancer

PubMed Central

Pan, Qun-Xiong; Su, Zi-Jian; Zhang, Jian-Hua; Wang, Chong-Ren; Ke, Shao-Ying

2015-01-01

Background People’s Republic of China is one of the countries with the highest incidence of gastric cancer, accounting for 45% of all new gastric cancer cases in the world. Therefore, strong prognostic markers are critical for the diagnosis and survival of Chinese patients suffering from gastric cancer. Recent studies have begun to unravel the mechanisms linking the host inflammatory response to tumor growth, invasion and metastasis in gastric cancers. Based on this relationship between inflammation and cancer progression, several inflammation-based scores have been demonstrated to have prognostic value in many types of malignant solid tumors. Objective To compare the prognostic value of inflammation-based prognostic scores and tumor node metastasis (TNM) stage in patients undergoing gastric cancer resection. Methods The inflammation-based prognostic scores were calculated for 207 patients with gastric cancer who underwent surgery. Glasgow prognostic score (GPS), neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), prognostic nutritional index (PNI), and prognostic index (PI) were analyzed. Linear trend chi-square test, likelihood ratio chi-square test, and receiver operating characteristic were performed to compare the prognostic value of the selected scores and TNM stage. Results In univariate analysis, preoperative serum C-reactive protein (P<0.001), serum albumin (P<0.001), GPS (P<0.001), PLR (P=0.002), NLR (P<0.001), PI (P<0.001), PNI (P<0.001), and TNM stage (P<0.001) were significantly associated with both overall survival and disease-free survival of patients with gastric cancer. In multivariate analysis, GPS (P=0.024), NLR (P=0.012), PI (P=0.001), TNM stage (P<0.001), and degree of differentiation (P=0.002) were independent predictors of gastric cancer survival. GPS and TNM stage had a comparable prognostic value and higher linear trend chi-square value, likelihood ratio chi-square value, and larger area under the receiver operating characteristic curve as compared to other inflammation-based prognostic scores. Conclusion The present study indicates that preoperative GPS and TNM stage are robust predictors of gastric cancer survival as compared to NLR, PLR, PI, and PNI in patients undergoing tumor resection. PMID:26124667

Examples of Data Analysis with SPSS/PC+ Studentware.

ERIC Educational Resources Information Center

MacFarland, Thomas W.

Intended for classroom use only, these unpublished notes contain computer lessons on descriptive statistics with files previously created in WordPerfect 4.2 and Lotus 1-2-3 Version 1.A for the IBM PC+. The statistical measures covered include Student's t-test with two independent samples; Student's t-test with a paired sample; Chi-square analysis;…

PTSD's latent structure in Malaysian tsunami victims: assessing the newly proposed Dysphoric Arousal model.

PubMed

Armour, Cherie; Raudzah Ghazali, Siti; Elklit, Ask

2013-03-30

The underlying latent structure of Posttraumatic Stress Disorder (PTSD) is widely researched. However, despite a plethora of factor analytic studies, no single model has consistently been shown as superior to alternative models. The two most often supported models are the Emotional Numbing and the Dysphoria models. However, a recently proposed five-factor Dysphoric Arousal model has been gathering support over and above existing models. Data for the current study were gathered from Malaysian Tsunami survivors (N=250). Three competing models (Emotional Numbing/Dysphoria/Dysphoric Arousal) were specified and estimated using Confirmatory Factor Analysis (CFA). The Dysphoria model provided superior fit to the data compared to the Emotional Numbing model. However, using chi-square difference tests, the Dysphoric Arousal model showed a superior fit compared to both the Emotional Numbing and Dysphoria models. In conclusion, the current results suggest that the Dysphoric Arousal model better represents PTSD's latent structure and that items measuring sleeping difficulties, irritability/anger and concentration difficulties form a separate, unique PTSD factor. These results are discussed in relation to the role of Hyperarousal in PTSD's on-going symptom maintenance and in relation to the DSM-5. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Relief from Back Pain Through Postural Adjustment: a Controlled Clinical Trial of the Immediate Effects of Muscular Chains Therapy (MCT).

PubMed

Rosario, Jose L

2014-09-01

Back pain can be one of the most common health problems, causing suffering, disabilities, and financial losses. Postural models for pain treatment state that poor posture alters the joint position and causes pain, such as back pain. Muscular Chain Therapy (MCT) is a technique that is used to treat posture pathologies, among others. The aim of the present study was to assess the efficiency of a single session of Muscular Chain Therapy (MCT) on complaints of undiagnosed musculoskeletal spinal pain. Physical therapy clinic of the University of Center-West (Guarapuava, Brazil). 100 subjects, aged between 20 and 39 years, with complaints of spinal musculoskeletal pain. Randomized controlled trial. The participants were randomly assigned by a non-care provider into two groups: The MCT Group that received Muscular Chain Treatment and the Control Group that received a placebo treatment of 15 minutes turned off ultrasound therapy. All volunteers were assessed before and after treatment using an analog pain scale. A score of 0 indicated no pain and 10 was the maximum degree of pain on the scale. Degree of pain measured by analog scale. The chi-square goodness of fit test was used to compare gender distribution among groups displayed a p value = .25. Subject age had differences analyzed using the unpaired t test (p = .44). Pain assessment for treatment and placebo control groups was analyzed using a paired t test and unpaired t test. The paired t test was used for intragroup before/after treatment comparison (MCT p = .00001; Control Group p = .0001). The unpaired t test was used for comparing the difference of the pain level before and after treatment between groups (p = .0001). A priori statistical significance was set a p = .05. It is possible to conclude that one MCT session is an effective treatment of undiagnosed spinal musculoskeletal pain.

Factor analysis for instruments of science learning motivation and its implementation for the chemistry and biology teacher candidates

NASA Astrophysics Data System (ADS)

Prasetya, A. T.; Ridlo, S.

2018-03-01

The purpose of this study is to test the learning motivation of science instruments and compare the learning motivation of science from chemistry and biology teacher candidates. Kuesioner Motivasi Sains (KMS) in Indonesian adoption of the Science Motivation Questionnaire II (SMQ II) consisting of 25 items with a 5-point Likert scale. The number of respondents for the Exploratory Factor Analysis (EFA) test was 312. The Kaiser-Meyer-Olkin (KMO), determinant, Bartlett’s Sphericity, Measures of Sampling Adequacy (MSA) tests against KMS using SPSS 20.0, and Lisrel 8.51 software indicate eligible indications. However testing of Communalities obtained results that there are 4 items not qualified, so the item is discarded. The second test, all parameters of eligibility and has a magnitude of Root Mean Square Error of Approximation (RMSEA), P-Value for the Test of Close Fit (RMSEA <0.05), Goodness of Fit Index (GFI) was good. The new KMS with 21 valid items and composite reliability of 0.9329 can be used to test the level of learning motivation of science which includes Intrinsic Motivation, Sefl-Efficacy, Self-Determination, Grade Motivation and Career Motivation for students who master the Indonesian language. KMS trials of chemistry and biology teacher candidates obtained no significant difference in the learning motivation between the two groups.

Design and validation of a self-administered test to assess bullying (bull-M) in high school Mexicans: a pilot study

PubMed Central

2013-01-01

Background Bullying (Bull) is a public health problem worldwide, and Mexico is not exempt. However, its epidemiology and early detection in our country is limited, in part, by the lack of validated tests to ensure the respondents’ anonymity. The aim of this study was to validate a self-administered test (Bull-M) for assessing Bull among high-school Mexicans. Methods Experts and school teachers from highly violent areas of Ciudad Juarez (Chihuahua, México), reported common Bull behaviors. Then, a 10-item test was developed based on twelve of these behaviors; the students’ and peers’ participation in Bull acts and in some somatic consequences in Bull victims with a 5-point Likert frequency scale. Validation criteria were: content (CV, judges); reliability [Cronbach’s alpha (CA), test-retest (spearman correlation, rs)]; construct [principal component (PCA), confirmatory factor (CFA), goodness-of-fit (GF) analysis]; and convergent (Bull-M vs. Bull-S test) validity. Results Bull-M showed good reliability (CA = 0.75, rs = 0.91; p < 0.001). Two factors were identified (PCA) and confirmed (CFA): “bullying me (victim)” and “bullying others (aggressor)”. GF indices were: Root mean square error of approximation (0.031), GF index (0.97), and normalized fit index (0.92). Bull-M was as good as Bull-S for measuring Bull prevalence. Conclusions Bull-M has a good reliability and convergent validity and a bi-modal factor structure for detecting Bull victims and aggressors; however, its external validity and sensitivity should be analyzed on a wider and different population. PMID:23577755

Syndromes of Self-Reported Psychopathology for Ages 18–59 in 29 Societies

PubMed Central

Achenbach, Thomas M.; Rescorla, Leslie A.; Tumer, Lori V.; Ahmeti-Pronaj, Adelina; Au, Alma; Maese, Carmen Avila; Bellina, Monica; Caldas, J. Carlos; Chen, Yi-Chuen; Csemy, Ladislav; da Rocha, Marina M.; Decoster, Jeroen; Dobrean, Anca; Ezpeleta, Lourdes; Fontaine, Johnny R. J.; Funabiki, Yasuko; Guðmundsson, Halldór S.; Harder, Valerie s; de la Cabada, Marie Leiner; Leung, Patrick; Liu, Jianghong; Mahr, Safia; Malykh, Sergey; Maras, Jelena Srdanovic; Markovic, Jasminka; Ndetei, David M.; Oh, Kyung Ja; Petot, Jean-Michel; Riad, Geylan; Sakarya, Direnc; Samaniego, Virginia C.; Sebre, Sandra; Shahini, Mimoza; Silvares, Edwiges; Simulioniene, Roma; Sokoli, Elvisa; Talcott, Joel B.; Vazquez, Natalia; Zasepa, Ewa

2017-01-01

This study tested the multi-society generalizability of an eight-syndrome assessment model derived from factor analyses of American adults’ self-ratings of 120 behavioral, emotional, and social problems. The Adult Self-Report (ASR; Achenbach and Rescorla 2003) was completed by 17,152 18–59-year-olds in 29 societies. Confirmatory factor analyses tested the fit of self-ratings in each sample to the eight-syndrome model. The primary model fit index (Root Mean Square Error of Approximation) showed good model fit for all samples, while secondary indices showed acceptable to good fit. Only 5 (0.06%) of the 8,598 estimated parameters were outside the admissible parameter space. Confidence intervals indicated that sampling fluctuations could account for the deviant parameters. Results thus supported the tested model in societies differing widely in social, political, and economic systems, languages, ethnicities, religions, and geographical regions. Although other items, societies, and analytic methods might yield different results, the findings indicate that adults in very diverse societies were willing and able to rate themselves on the same standardized set of 120 problem items. Moreover, their self-ratings fit an eight-syndrome model previously derived from self-ratings by American adults. The support for the statistically derived syndrome model is consistent with previous findings for parent, teacher, and self-ratings of 1½–18-year-olds in many societies. The ASR and its parallel collateral-report instrument, the Adult Behavior Checklist (ABCL), may offer mental health professionals practical tools for the multi-informant assessment of clinical constructs of adult psychopathology that appear to be meaningful across diverse societies. PMID:29805197

Psychometric Evaluation of the Ford Insomnia Response to Stress Test (FIRST) in Early Pregnancy.

PubMed

Gelaye, Bizu; Zhong, Qiu-Yue; Barrios, Yasmin V; Redline, Susan; Drake, Christopher L; Williams, Michelle A

2016-04-15

To evaluate the construct validity and factor structure of the Spanish-language version of the Ford Insomnia Response to Stress Test questionnaire (FIRST-S) when used in early pregnancy. A cohort of 647 women were interviewed at ≤ 16 weeks of gestation to collect information regarding lifestyle, demographic, and sleep characteristics. The factorial structure of the FIRST-S was tested through exploratory and confirmatory factor analyses (EFA and CFA). Internal consistency and construct validity were also assessed by evaluating the association between the FIRST-S with symptoms of depression, anxiety, and sleep quality. Item response theory (IRT) analyses were conducted to complement classical test theory (CTT) analytic approaches. The mean score of the FIRST-S was 13.8 (range: 9-33). The results of the EFA showed that the FIRST-S contained a one-factor solution that accounted for 69.8% of the variance. The FIRST-S items showed good internal consistency (Cronbach α = 0.81). CFA results corroborated the one-factor structure finding from the EFA; and yielded measures indicating goodness of fit (comparative fit index of 0.902) and accuracy (root mean square error of approximation of 0.057). The FIRST-S had good construct validity as demonstrated by statistically significant associations of FIRST-S scores with sleep quality, antepartum depression and anxiety symptoms. Finally, results from IRT analyses suggested excellent item infit and outfit measures. The FIRST-S was found to have good construct validity and internal consistency for assessing vulnerability to insomnia during early pregnancy. © 2016 American Academy of Sleep Medicine.

Some Small Sample Results for Maximum Likelihood Estimation in Multidimensional Scaling.

ERIC Educational Resources Information Center

Ramsay, J. O.

1980-01-01

Some aspects of the small sample behavior of maximum likelihood estimates in multidimensional scaling are investigated with Monte Carlo techniques. In particular, the chi square test for dimensionality is examined and a correction for bias is proposed and evaluated. (Author/JKS)

One year comparative clinical evaluation of EQUIA with resin-modified glass ionomer and a nanohybrid composite in noncarious cervical lesions

PubMed Central

Vaid, Deepa Sunil; Shah, Nimisha Chinmay; Bilgi, Priyanka Shripad

2015-01-01

Aims: Comparative evaluation of EQUIA with a resin-modified glass ionomer cement (RMGIC; GC Gold Label glass ionomer light cured universal restorative cement) and a nanohybrid composite (Tetric N-Ceram) in noncarious cervical lesions (NCCLs). Background: To establish the most suitable material for the restoration of NCCLs. Settings and Design: In vivo study. Materials and Methods: Eighty-seven NCCLs were randomly restored with EQUIA, a RMGIC, and a nanohybrid composite. Clinical evaluation of the restorations was done following the Unites States Public Health criteria by a single-blinded investigator. Data were formulated, and statistical analysis was done by Chi-square test. Statistical Analysis Used: Chi-square test. Results: No significant difference was found between EQUIA, RMGIC, and nanohybrid composite at 1-month, at 6 months, and at 1-year (P > 0.05). Conclusions: EQUIA, resin-modified glass ionomer, and nanohybrid composite performed equally at 1-month, 6 months, and 1-year follow-up periods. PMID:26752837

Thermostability of heterophile antibodies from human sera infected with Schistosoma mansoni and geo-helminths. An immuno-metric statistical analysis.

PubMed

Chamone, Munir; Atuncar, Gregorio S; Coelho, Paulo Marcos Zech

2006-01-01

Antibody in human sera that induces lysis of sheep erythrocytes in hemolytic assay was investigated. The present study showed that the presence in serum of the thermostable cytolytic anti-sheep red blood cells antibodies is dependent on the Schistosoma mansoni infection, and this is more frequent in adults than in children. The thermostable characteristic of hemolysins in normal sera was not dependent on the presence of Ascaris lumbricoides, Trichuris trichiura or hookworm geo-helminths. Further, thermostable complement-activating heterophile antibodies were noticed in children in association with massive number of S. mansoni eggs. The results were obtained by using the z- and the chi-square tests. The z-test allows us to formulate a one-sided alternative, i.e., a tendency of one of the attributes. On the other hand, the chi-square test analyzes the independence between attributes by using a contingency table. Besides the obtained results being interesting in the field of schistosomiasis mansoni, they can provide a new insight into the use of statistics in medical science.

Open-Ended Laboratory Investigations with Drosophila.

ERIC Educational Resources Information Center

Mertens, Thomas R.

1983-01-01

Background information, laboratory procedures (including matings performed), and results are presented for an open-ended investigation using the fruitfly Drosophila melanogaster. Once data are collected, students develop hypotheses to explain results as well as devise additional experiments to test their hypotheses. Calculation of chi-square for…

HIV-Related Risk Behaviors, Perceptions of Risk, HIV Testing, and Exposure to Prevention Messages and Methods among Urban American Indians and Alaska Natives

ERIC Educational Resources Information Center

Lapidus, Jodi A.; Bertolli, Jeanne; McGowan, Karen; Sullivan, Patrick

2006-01-01

The goal of this study was to describe HIV risk behaviors, perceptions, testing, and prevention exposure among urban American Indians and Alaska Natives (AI/AN). Interviewers administered a questionnaire to participants recruited through anonymous peer-referral sampling. Chi-square tests and multiple logistic regression were used to compare HIV…

[Effects of community health promotion project for garlic cultivating farmers based on self-efficacy theory and community capacity building framework].

PubMed

Kim, Hyang-Sook; Gu, Mee Ock

2011-02-01

This study was conducted to test the effects of a community health promotion project for farmers cultivating garlic. Bandura's self-efficacy theory (1986) and Chaskin's community capacity framework (2001) were used as the theoretical framework. A nonequivalent control group pretest-posttest design was used. Study participants were 72 garlic farmers (intervention: 36, control: 36). The community health promotion project consisted of health promotion program and community capacity building strategies and was provided for 12 weeks (8 during farming off-season and 4 during farming season). Data were collected between February 23 and May 31, 2009 and were analyzed using chi-square test, Fisher's exact test, t-test, and repeated measure ANOVA using SPSS/WIN 12.0. For the experimental group, significant improvement was found for self-efficacy, farming related health behavior, physical fitness (muscle strength, muscle endurance, upper body flexibility, lower body flexibility, cardiovascular endurance, balance, agility), farmer's syndrome, and health related quality of life as compared to the control group. The findings of the study indicate that the community health promotion project for garlic farmers is effective and can be recommended as a nursing intervention for health promotion of garlic cultivating farmers.

Validity and reliability of the Multidimensional Body Image Scale in Malaysian university students.

PubMed

Gan, W Y; Mohd, Nasir M T; Siti, Aishah H; Zalilah, M S

2012-12-01

This study aimed to evaluate the validity and reliability of the Multidimensional Body Image Scale (MBIS), a seven-factor, 62-item scale developed for Malaysian female adolescents. This scale was evaluated among male and female Malaysian university students. A total of 671 university students (52.2% women and 47.8% men) completed a self-administered questionnaire on MBIS, Eating Attitude Test-26, and Rosenberg Self-Esteem Scale. Their height and weight were measured. Results in confirmatory factor analysis showed that the 62-item MBIS reported poor fit to the data, xhi2/df = 4.126, p < 0.001, CFI = 0.808, SRMR = 0.070, RMSEA = 0.068 (90% CI = 0.067, 0.070). After re-specification of the model, the model fit was improved with 46 items remaining, chi2/df = 3.346, p < 0.001, CFI = 0.903, SRMR = 0.053, RMSEA = 0.059 (90% CI = 0.057, 0.061), and the model showed good fit to the data for men and women separately. This 46-item MBIS had good internal consistency in both men (Cronbach's alpha = 0.88) and women (Cronbach's alpha = 0.92). In terms of construct validity, it showed positive correlations with disordered eating and body weight status, but negative correlation with self-esteem. Also, this scale discriminated well between participants with and without disordered eating. The MBIS-46 demonstrated good reliability and validity for the evaluation of body image among university students. Further studies need to be conducted to confirm the validation results of the 46-item MBIS.

Predictors of Relapse after Discontinuing Systemic Treatment in Childhood Autoimmune Chronic Uveitis.

PubMed

Simonini, Gabriele; Bracaglia, Claudia; Cattalini, Marco; Taddio, Andrea; Brambilla, Alice; De Libero, Cinzia; Pires Marafon, Denise; Caputo, Roberto; Cimaz, Rolando

2017-06-01

To identify clinical predictors of relapse in childhood autoimmune chronic uveitis after stopping systemic treatment. A retrospective, multicenter, cohort study. Ninety-four children in remission, receiving no treatments and with at least a 6-month followup, were enrolled. A higher probability of maintaining remission after discontinuing treatment was shown in idiopathic compared with juvenile idiopathic arthritis uveitis (Mantel-Cox chi-square = 23.21) if inactivity had been obtained within 6 months from starting systemic treatment (Mantel-Cox chi-square = 24.17) and by antitumor necrosis factor-α treatment (Mantel-Cox chi-square = 6.43). Type of disease, time, and type of systemic therapy to achieve inactivity predict different duration of uveitis remission after treatment withdrawal.

Clinical variables related to antidepressant-induced mania in bipolar disorder.

PubMed

Mundo, Emanuela; Cattaneo, Elisabetta; Russo, Michela; Altamura, A Carlo

2006-06-01

The development of mania or hypomania during antidepressant treatment is a serious complication of the clinical management of bipolar disorder (BP). The primary aim of this study was to evaluate the clinical variables related to antidepressant-induced mania or hypomania (AIM) in patients with BP. DSM-IV BP-I or BP-II patients who had had at least one depressive episode treated with antidepressants were considered. Patients were subdivided into two groups according to the presence (n = 30) or absence (n = 106) of manic or hypomanic episodes occurring during antidepressant treatment. Possible predictive clinical variables of AIM were considered: gender, diagnostic subtype, age at onset, duration of illness, duration of untreated illness, type of antidepressant administered, number of previous spontaneous hypomanic or manic episodes, number of previous depressive episodes, presence of lifetime suicide attempts, presence of mood stabilizer treatments, presence of psychotic symptoms during spontaneous episodes, family history for psychiatric disorders in first degree relatives. Data were compared between the two groups, with (AIM+) and without (AIM-) antidepressant-induced mania, using Student's t tests and chi-square tests. The lack of mood stabilizer treatments during antidepressant therapy (chi-square = 37.602, df = 1, p < 0.001) and the exposure to tricyclic antidepressants (chi-square = 4.901, df = 1, p < 0.05) resulted significantly associated to the development of AIM. This study was not done under controlled conditions and the relatively small sample studied warrants further replications. These results point out the risk of mania induction associated to the use of tricyclic antidepressants in BP patients, mainly in absence of adequate mood stabilizers.

Non-linear Multidimensional Optimization for use in Wire Scanner Fitting

NASA Astrophysics Data System (ADS)

Henderson, Alyssa; Terzic, Balsa; Hofler, Alicia; Center Advanced Studies of Accelerators Collaboration

2014-03-01

To ensure experiment efficiency and quality from the Continuous Electron Beam Accelerator at Jefferson Lab, beam energy, size, and position must be measured. Wire scanners are devices inserted into the beamline to produce measurements which are used to obtain beam properties. Extracting physical information from the wire scanner measurements begins by fitting Gaussian curves to the data. This study focuses on optimizing and automating this curve-fitting procedure. We use a hybrid approach combining the efficiency of Newton Conjugate Gradient (NCG) method with the global convergence of three nature-inspired (NI) optimization approaches: genetic algorithm, differential evolution, and particle-swarm. In this Python-implemented approach, augmenting the locally-convergent NCG with one of the globally-convergent methods ensures the quality, robustness, and automation of curve-fitting. After comparing the methods, we establish that given an initial data-derived guess, each finds a solution with the same chi-square- a measurement of the agreement of the fit to the data. NCG is the fastest method, so it is the first to attempt data-fitting. The curve-fitting procedure escalates to one of the globally-convergent NI methods only if NCG fails, thereby ensuring a successful fit. This method allows for the most optimal signal fit and can be easily applied to similar problems.

Reasons for the increasing Hispanic infant mortality rate: Florida, 2004-2007.

PubMed

Sauber-Schatz, Erin K; Sappenfield, William; Hernandez, Leticia; Freeman, Karen M; Barfield, Wanda; Bensyl, Diana M

2012-08-01

Assess whether the 55% increase in Florida's Hispanic infant mortality rate (HIMR) during 2004-2007 was real or artifactual. Using linked data from Florida resident live births and infant deaths for 2004-2007, we calculated traditional (infant Hispanic ethnicity from death certificates and maternal Hispanic ethnicity from birth certificates) and nontraditional (infant and maternal Hispanic ethnicity from birth certificate maternal ethnicity) HIMRs. We assessed trends in HIMRs (per 1,000 live births) using Chi-square statistics. We tested agreement in Hispanic ethnicity after implementation of a revised 2005 death certificate by using kappa statistics and used logistic regression to test the associations of infant mortality risk factors. Hispanic was defined as being of Mexican, Puerto Rican, Cuban, Central/South American, or other/unknown Hispanic origin. During 2004-2007 traditional HIMR increased 55%, from 4.0 to 6.2 (Chi-square, P < 0.001) and nontraditional HIMR increased 20%, from 4.5 to 5.4 (Chi-square, P = 0.03). During 2004-2005, agreement in Hispanic ethnicity did not change with use of the revised certificate (kappa = 0.70 in 2004; kappa = 0.76 in 2005). Birth weight was the most significant risk factor for trends in Hispanic infant mortality (OR = 1.33, 95% CI = 1.10-1.61). Differences in Hispanic reporting on revised death certificates likely accounted for the majority of traditional HIMR increase, indicating a primarily artifactual increase. Reasons for the 20% increase in nontraditional HIMR during 2004-2007 should be further explored through other individual and community factors. Use of nontraditional HIMRs, which use a consistent source of Hispanic classification, should be considered.

Nutritional Status of Rural Older Adults Is Linked to Physical and Emotional Health.

PubMed

Jung, Seung Eun; Bishop, Alex J; Kim, Minjung; Hermann, Janice; Kim, Giyeon; Lawrence, Jeannine

2017-06-01

Although nutritional status is influenced by multidimensional aspects encompassing physical and emotional well-being, there is limited research on this complex relationship. The purpose of this study was to examine the interplay between indicators of physical health (perceived health status and self-care capacity) and emotional well-being (depressive affect and loneliness) on rural older adults' nutritional status. The cross-sectional study was conducted from June 1, 2007, to June 1, 2008. A total of 171 community-dwelling older adults, aged 65 years and older, residing within nonmetro rural communities in the United States participated in this study. Participants completed validated instruments measuring self-care capacity, perceived health status, loneliness, depressive affect, and nutritional status. Structural equation modeling was employed to investigate the complex interplay of physical and emotional health status with nutritional status among rural older adults. The χ 2 test, comparative fit index, root mean square error of approximation, and standardized root mean square residual were used to assess model fit. The χ 2 test and the other model fit indexes showed the hypothesized structural equation model provided a good fit to the data (χ 2 (2)=2.15; P=0.34; comparative fit index=1.00; root mean square error of approximation=0.02; and standardized root mean square residual=0.03). Self-care capacity was significantly related with depressive affect (γ=-0.11; P=0.03), whereas self-care capacity was not significantly related with loneliness. Perceived health status had a significant negative relationship with both loneliness (γ=-0.16; P=0.03) and depressive affect (γ=-0.22; P=0.03). Although loneliness showed no significant direct relationship with nutritional status, it showed a significant direct relationship with depressive affect (β=.4; P<0.01). Finally, the results demonstrated that depressive affect had a significant negative relationship with nutritional status (β=-.30; P<0.01). The results indicated physical health and emotional indicators have significant multidimensional associations with nutritional status among rural older adults. The present study provides insights into the importance of addressing both physical and emotional well-being together to reduce potential effects of poor emotional well-being on nutritional status, particularly among rural older adults with impaired physical health and self-care capacity. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Glacial isostatic adjustment using GNSS permanent stations and GIA modelling tools

NASA Astrophysics Data System (ADS)

Kollo, Karin; Spada, Giorgio; Vermeer, Martin

2013-04-01

Glacial Isostatic Adjustment (GIA) affects the Earth's mantle in areas which were once ice covered and the process is still ongoing. In this contribution we focus on GIA processes in Fennoscandian and North American uplift regions. In this contribution we use horizontal and vertical uplift rates from Global Navigation Satellite System (GNSS) permanent stations. For Fennoscandia the BIFROST dataset (Lidberg, 2010) and North America the dataset from Sella, 2007 were used respectively. We perform GIA modelling with the SELEN program (Spada and Stocchi, 2007) and we vary ice model parameters in space in order to find ice model which suits best with uplift values obtained from GNSS time series analysis. In the GIA modelling, the ice models ICE-5G (Peltier, 2004) and the ice model denoted as ANU05 ((Fleming and Lambeck, 2004) and references therein) were used. As reference, the velocity field from GNSS permanent station time series was used for both target areas. Firstly the sensitivity to the harmonic degree was tested in order to reduce the computation time. In the test, nominal viscosity values and pre-defined lithosphere thicknesses models were used, varying maximum harmonic degree values. Main criteria for choosing the suitable harmonic degree was chi-square fit - if the error measure does not differ more than 10%, then one might use as well lower harmonic degree value. From this test, maximum harmonic degree of 72 was chosen to perform calculations, as the larger value did not significantly modify the results obtained, as well the computational time for observations was kept reasonable. Secondly the GIA computations were performed to find the model, which could fit with highest probability to the GNSS-based velocity field in the target areas. In order to find best fitting Earth viscosity parameters, different viscosity profiles for the Earth models were tested and their impact on horizontal and vertical velocity rates from GIA modelling was studied. For every tested model the chi-square misfit for horizontal, vertical and three-dimensional velocity rates from the reference model was found (Milne, 2001). Finally, the best fitting models from GIA modelling were compared with rates obtained from GNSS data. Keywords: Fennoscandia, North America, land uplift, glacial isostatic adjustment, visco-elastic modelling, BIFROST. References Lidberg, M., Johannson, J., Scherneck, H.-G. and Milne, G. (2010). Recent results based on continuous GPS observations of the GIA process in Fennoscandia from BIFROST. Journal of Geodynamics, 50. pp. 8-18. Sella, G. F., Stein, S., Dixon, T. H., Craymer, M., James, T. S., Mazotti, S. and Dokka, R. K. (2007). Observations of glacial isostatic adjustment in "stable" North America with GPS. Geophysical Research Letters, 34, L02306. Spada, G., Stocchi, P. (2007). SELEN: A Fortran 90 program for solving the "sea-level equation". Computers & Geosciences, 33:538-562, 2007. Peltier, W. R. (2004). Global glacial isostasy and the surface of the ice-age Earth: The Ice-5G (VM2) model and GRACE. Annu. Rev. Earth Planet. Sci., 32:111-149, 2004. Fleming, K. and Lambeck, K. (2004). Constraints on the Greenland Ice Sheet since the Last Glacial Maximum from sea-level observations and glacial-rebound models. Quaternary Science Reviews 23 (2004), pp. 1053-1077. Milne, G. A. and Davis, J. L. and Mitrovica, J. X. and Scherneck, H.-G. and Johansson, J. M. and Vermeer, M. and Koivula, H. (2001). Space-geodetic constraints on glacial isostatic adjustment in Fennoscandia. Science 291 (2001), pp. 2381-2385.

Optimal iodine-131 dose for eliminating hyperthyroidism in Graves' disease

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

Nordyke, R.A.; Gilbert, F.I. Jr.

1991-03-01

Since hypothyroidism is commonplace after treatment of Graves' disease with radioiodine, the goal should be cure of hyperthyroidism rather than avoidance of hypothyroidism. To find the optimal dose to accomplish cure, we treated 605 patients with stepwise increasing doses of 3, 4, 5, 6, 8, and 10 mCi, analyzing the relationship of dose, age, sex, gland weight, and thyroidal uptake to cure. Estimates of cure at doses above 10 mCi were made from the literature. Cure was directly related to dose between 5 and 10 mCi. There was no significant relationship between cure and age (chi-square, p = 0.74), sexmore » (chi-square, p = 0.12), and 24-hr uptake if over 30% (chi-square for slope, p greater than 0.10). Cure and gland weight had an inverse relationship (chi-square for slope, 0.01 less than p less than 0.02). We concluded that the optimal 131I dose for curing hyperthyroidism is approximated by starting with 10 mCi and increasing it for unusually large glands or for special patient circumstances.« less

Investigation into solar drying of potato: effect of sample geometry on drying kinetics and CO2 emissions mitigation.

PubMed

Tripathy, P P

2015-03-01

Drying experiments have been performed with potato cylinders and slices using a laboratory scale designed natural convection mixed-mode solar dryer. The drying data were fitted to eight different mathematical models to predict the drying kinetics, and the validity of these models were evaluated statistically through coefficient of determination (R(2)), root mean square error (RMSE) and reduced chi-square (χ (2)). The present investigation showed that amongst all the mathematical models studied, the Modified Page model was in good agreement with the experimental drying data for both potato cylinders and slices. A mathematical framework has been proposed to estimate the performance of the food dryer in terms of net CO2 emissions mitigation potential along with unit cost of CO2 mitigation arising because of replacement of different fossil fuels by renewable solar energy. For each fossil fuel replaced, the gross annual amount of CO2 as well as net amount of annual CO2 emissions mitigation potential considering CO2 emissions embodied in the manufacture of mixed-mode solar dryer has been estimated. The CO2 mitigation potential and amount of fossil fuels saved while drying potato samples were found to be the maximum for coal followed by light diesel oil and natural gas. It was inferred from the present study that by the year 2020, 23 % of CO2 emissions can be mitigated by the use of mixed-mode solar dryer for drying of agricultural products.

Preschool psychopathology reported by parents in 23 societies: testing the seven-syndrome model of the child behavior checklist for ages 1.5-5.

PubMed

Ivanova, Masha Y; Achenbach, Thomas M; Rescorla, Leslie A; Harder, Valerie S; Ang, Rebecca P; Bilenberg, Niels; Bjarnadottir, Gudrun; Capron, Christiane; De Pauw, Sarah S W; Dias, Pedro; Dobrean, Anca; Doepfner, Manfred; Duyme, Michele; Eapen, Valsamma; Erol, Nese; Esmaeili, Elaheh Mohammad; Ezpeleta, Lourdes; Frigerio, Alessandra; Gonçalves, Miguel M; Gudmundsson, Halldor S; Jeng, Suh-Fang; Jetishi, Pranvera; Jusiene, Roma; Kim, Young-Ah; Kristensen, Solvejg; Lecannelier, Felipe; Leung, Patrick W L; Liu, Jianghong; Montirosso, Rosario; Oh, Kyung Ja; Plueck, Julia; Pomalima, Rolando; Shahini, Mimoza; Silva, Jaime R; Simsek, Zynep; Sourander, Andre; Valverde, Jose; Van Leeuwen, Karla G; Woo, Bernardine S C; Wu, Yen-Tzu; Zubrick, Stephen R; Verhulst, Frank C

2010-12-01

To test the fit of a seven-syndrome model to ratings of preschoolers' problems by parents in very diverse societies. Parents of 19,106 children 18 to 71 months of age from 23 societies in Asia, Australasia, Europe, the Middle East, and South America completed the Child Behavior Checklist for Ages 1.5-5 (CBCL/1.5-5). Confirmatory factor analyses were used to test the seven-syndrome model separately for each society. The primary model fit index, the root mean square error of approximation (RMSEA), indicated acceptable to good fit for each society. Although a six-syndrome model combining the Emotionally Reactive and Anxious/Depressed syndromes also fit the data for nine societies, it fit less well than the seven-syndrome model for seven of the nine societies. Other fit indices yielded less consistent results than the RMSEA. The seven-syndrome model provides one way to capture patterns of children's problems that are manifested in ratings by parents from many societies. Clinicians working with preschoolers from these societies can thus assess and describe parents' ratings of behavioral, emotional, and social problems in terms of the seven syndromes. The results illustrate possibilities for culture-general taxonomic constructs of preschool psychopathology. Problems not captured by the CBCL/1.5-5 may form additional syndromes, and other syndrome models may also fit the data. Copyright © 2010 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Preschool Psychopathology Reported by Parents in 23 Societies: Testing the Seven-Syndrome Model of the Child Behavior Checklist for Ages 1.5–5

PubMed Central

Ivanova, Masha Y.; Achenbach, Thomas M.; Rescorla, Leslie A.; Harder, Valerie S.; Ang, Rebecca P.; Bilenberg, Niels; Bjarnadottir, Gudrun; Capron, Christiane; De Pauw, Sarah S.W.; Dias, Pedro; Dobrean, Anca; Doepfner, Manfred; Duyme, Michele; Eapen, Valsamma; Erol, Nese; Esmaeili, Elaheh Mohammad; Ezpeleta, Lourdes; Frigerio, Alessandra; Gonçalves, Miguel M.; Gudmundsson, Halldor S.; Jeng, Suh-Fang; Jetishi, Pranvera; Jusiene, Roma; Kim, Young-Ah; Kristensen, Solvejg; Lecannelier, Felipe; Leung, Patrick W.L.; Liu, Jianghong; Montirosso, Rosario; Oh, Kyung Ja; Plueck, Julia; Pomalima, Rolando; Shahini, Mimoza; Silva, Jaime R.; Simsek, Zynep; Sourander, Andre; Valverde, Jose; Van Leeuwen, Karla G.; Woo, Bernardine S.C.; Wu, Yen-Tzu; Zubrick, Stephen R.; Verhulst, Frank C.

2014-01-01

Objective To test the fit of a seven-syndrome model to ratings of preschoolers' problems by parents in very diverse societies. Method Parents of 19,106 children 18 to 71 months of age from 23 societies in Asia, Australasia, Europe, the Middle East, and South America completed the Child Behavior Checklist for Ages 1.5–5 (CBCL/1.5–5). Confirmatory factor analyses were used to test the seven-syndrome model separately for each society. Results The primary model fit index, the root mean square error of approximation (RMSEA), indicated acceptable to good fit for each society. Although a six-syndrome model combining the Emotionally Reactive and Anxious/Depressed syndromes also fit the data for nine societies, it fit less well than the seven-syndrome model for seven of the nine societies. Other fit indices yielded less consistent results than the RMSEA. Conclusions The seven-syndrome model provides one way to capture patterns of children's problems that are manifested in ratings by parents from many societies. Clinicians working with preschoolers from these societies can thus assess and describe parents' ratings of behavioral, emotional, and social problems in terms of the seven syndromes. The results illustrate possibilities for culture–general taxonomic constructs of preschool psychopathology. Problems not captured by the CBCL/1.5–5 may form additional syndromes, and other syndrome models may also fit the data. PMID:21093771

The applicability of ordinary least squares to consistently short distances between taxa in phylogenetic tree construction and the normal distribution test consequences.

PubMed

Roux, C Z

2009-05-01

Short phylogenetic distances between taxa occur, for example, in studies on ribosomal RNA-genes with slow substitution rates. For consistently short distances, it is proved that in the completely singular limit of the covariance matrix ordinary least squares (OLS) estimates are minimum variance or best linear unbiased (BLU) estimates of phylogenetic tree branch lengths. Although OLS estimates are in this situation equal to generalized least squares (GLS) estimates, the GLS chi-square likelihood ratio test will be inapplicable as it is associated with zero degrees of freedom. Consequently, an OLS normal distribution test or an analogous bootstrap approach will provide optimal branch length tests of significance for consistently short phylogenetic distances. As the asymptotic covariances between branch lengths will be equal to zero, it follows that the product rule can be used in tree evaluation to calculate an approximate simultaneous confidence probability that all interior branches are positive.

An Empirical Investigation of Methods for Assessing Item Fit for Mixed Format Tests

ERIC Educational Resources Information Center

Chon, Kyong Hee; Lee, Won-Chan; Ansley, Timothy N.

2013-01-01

Empirical information regarding performance of model-fit procedures has been a persistent need in measurement practice. Statistical procedures for evaluating item fit were applied to real test examples that consist of both dichotomously and polytomously scored items. The item fit statistics used in this study included the PARSCALE's G[squared],…

Personality and the predisposition(s) to bipolar disorder: heuristic benefits of a two-dimensional model.

PubMed

Murray, Greg; Goldstone, Eliot; Cunningham, Everarda

2007-08-01

The aim of this study was to model normal personality correlates of the predisposition(s) to bipolar disorder (BD), and in so doing explore the proposition that the tendency to bipolar depression [trait depression (T-Depression)] and the tendency to mania [trait mania (T-Mania)] can usefully be viewed as separable but correlated dimensions of BD predisposition. A well student sample (n = 176, modal age 18-25 years, 71% female) completed the NEO Personality Inventory-Revised and the General Behavior Inventory. A good-fitting model (normed chi2 = 0.60, significance of chi2 = 0.73) was identified in which T-Depression was determined solely by neuroticism, while T-Mania was determined by extraversion and (negative) agreeableness. The pathway from T-Depression to T-Mania was also significant (standardized regression weight = 0.80), with a weaker significant reciprocal path (coefficient = 0.27). A model in which bipolar vulnerability was represented as a single dimension (T-Bipolarity) also provided a good fit to the data, but provided less heuristic power. Predisposition to BD can be usefully understood in terms of two reciprocally related dimensions of vulnerability (T-Depression and T-Mania), which can be separated on the basis of their personality correlates.

Season of birth and multiple sclerosis in Tunisia.

PubMed

Sidhom, Youssef; Kacem, Imen; Bayoudh, Lamia; Ben Djebara, Mouna; Hizem, Yosr; Ben Abdelfettah, Sami; Gargouri, Amina; Gouider, Riadh

2015-11-01

Recent studies on date of birth of multiple sclerosis (MS) patients showed an association between month of birth and the risk of developing MS. This association has not been investigated in an African country. We aimed to determine if the risk of MS is associated with month of birth in Tunisia. Data concerning date of birth for MS patients in Tunisia (n = 1912) was obtained. Birth rates of MS patients were compared with all births in Tunisia matched by year of birth (n = 11,615,912). We used a chi-squared analysis and the Hewitt's non-parametric test for seasonality. The distribution of births among MS patients compared with the control population was not different when tested by the chi-squared test. The Hewitt's test for seasonality showed an excess of births between May and October among MS patients (p = 0.03). The peak of Births of MS patients in Tunisia was in July and the nadir in December. Our data does support the seasonality hypothesis of month of birth as risk factor for MS in Tunisia. Low vitamin D levels during pregnancy could be a possible explanation that needs further investigation. Copyright © 2015 Elsevier B.V. All rights reserved.

Curve fitting of the corporate recovery rates: the comparison of Beta distribution estimation and kernel density estimation.

PubMed

Chen, Rongda; Wang, Ze

2013-01-01

Recovery rate is essential to the estimation of the portfolio's loss and economic capital. Neglecting the randomness of the distribution of recovery rate may underestimate the risk. The study introduces two kinds of models of distribution, Beta distribution estimation and kernel density distribution estimation, to simulate the distribution of recovery rates of corporate loans and bonds. As is known, models based on Beta distribution are common in daily usage, such as CreditMetrics by J.P. Morgan, Portfolio Manager by KMV and Losscalc by Moody's. However, it has a fatal defect that it can't fit the bimodal or multimodal distributions such as recovery rates of corporate loans and bonds as Moody's new data show. In order to overcome this flaw, the kernel density estimation is introduced and we compare the simulation results by histogram, Beta distribution estimation and kernel density estimation to reach the conclusion that the Gaussian kernel density distribution really better imitates the distribution of the bimodal or multimodal data samples of corporate loans and bonds. Finally, a Chi-square test of the Gaussian kernel density estimation proves that it can fit the curve of recovery rates of loans and bonds. So using the kernel density distribution to precisely delineate the bimodal recovery rates of bonds is optimal in credit risk management.

Curve Fitting of the Corporate Recovery Rates: The Comparison of Beta Distribution Estimation and Kernel Density Estimation

PubMed Central

Chen, Rongda; Wang, Ze

2013-01-01

Recovery rate is essential to the estimation of the portfolio’s loss and economic capital. Neglecting the randomness of the distribution of recovery rate may underestimate the risk. The study introduces two kinds of models of distribution, Beta distribution estimation and kernel density distribution estimation, to simulate the distribution of recovery rates of corporate loans and bonds. As is known, models based on Beta distribution are common in daily usage, such as CreditMetrics by J.P. Morgan, Portfolio Manager by KMV and Losscalc by Moody’s. However, it has a fatal defect that it can’t fit the bimodal or multimodal distributions such as recovery rates of corporate loans and bonds as Moody’s new data show. In order to overcome this flaw, the kernel density estimation is introduced and we compare the simulation results by histogram, Beta distribution estimation and kernel density estimation to reach the conclusion that the Gaussian kernel density distribution really better imitates the distribution of the bimodal or multimodal data samples of corporate loans and bonds. Finally, a Chi-square test of the Gaussian kernel density estimation proves that it can fit the curve of recovery rates of loans and bonds. So using the kernel density distribution to precisely delineate the bimodal recovery rates of bonds is optimal in credit risk management. PMID:23874558

The effect of message type on physician compliance with disease reporting requirements.

PubMed

Brissette, Ian; Gelberg, Kitty H; Grey, Anthony J

2006-01-01

Despite the existence of mandatory reporting laws, the underreporting of disease conditions to public health authorities is widespread. This article describes an evaluation of the effects of using different appeals to promote complete and timely reporting to the New York State Occupational Lung Disease Registry (NYS OLDR). Three-hundred sixty-eight physicians who had not reported patients were randomly assigned to receive correspondence emphasizing either the legal obligation to report, the public health benefits of reporting, or both. Chi-square tests were used to determine if the proportion of physicians who subsequently reported patients differed by message group. Chi-square tests and the Kruskall Wallis rank sum test were used to test for differences in the completeness and timeliness of reports received from physicians in the three message groups. Physicians receiving correspondence describing the legal obligation to report were more likely to report patients than those receiving only the benefit message, while those receiving correspondence describing the public health benefits of reporting submitted more complete reports than those receiving only the obligation message. To maximize physician reporting, it is important for public health agencies to emphasize both the legal and public health basis for reporting conditions in correspondence to physicians.

Spatially explicit habitat models for 28 fishes from the Upper Mississippi River System (AHAG 2.0)

USGS Publications Warehouse

Ickes, Brian S.; Sauer, J.S.; Richards, N.; Bowler, M.; Schlifer, B.

2014-01-01

Environmental management actions in the Upper Mississippi River System (UMRS) typically require pre-project assessments of predicted benefits under a range of project scenarios. The U.S. Army Corps of Engineers (USACE) now requires certified and peer-reviewed models to conduct these assessments. Previously, habitat benefits were estimated for fish communities in the UMRS using the Aquatic Habitat Appraisal Guide (AHAG v.1.0; AHAG from hereon). This spreadsheet-based model used a habitat suitability index (HSI) approach that drew heavily upon Habitat Evaluation Procedures (HEP; U.S. Fish and Wildlife Service, 1980) by the U.S. Fish and Wildlife Service (USFWS). The HSI approach requires developing species response curves for different environmental variables that seek to broadly represent habitat. The AHAG model uses species-specific response curves assembled from literature values, data from other ecosystems, or best professional judgment. A recent scientific review of the AHAG indicated that the model’s effectiveness is reduced by its dated approach to large river ecosystems, uncertainty regarding its data inputs and rationale for habitat-species response relationships, and lack of field validation (Abt Associates Inc., 2011). The reviewers made two major recommendations: (1) incorporate empirical data from the UMRS into defining the empirical response curves, and (2) conduct post-project biological evaluations to test pre-project benefits estimated by AHAG. Our objective was to address the first recommendation and generate updated response curves for AHAG using data from the Upper Mississippi River Restoration-Environmental Management Program (UMRR-EMP) Long Term Resource Monitoring Program (LTRMP) element. Fish community data have been collected by LTRMP (Gutreuter and others, 1995; Ratcliff and others, in press) for 20 years from 6 study reaches representing 1,930 kilometers of river and >140 species of fish. We modeled a subset of these data (28 different species; occurrences at sampling sites as observed in day electrofishing samples) using multiple logistic regression with presence/absence responses. Each species’ probability of occurrence, at each sample site, was modeled as a function of 17 environmental variables observed at each sample site by LTRMP standardized protocols. The modeling methods used (1) a forward-selection process to identify the most important predictors and their relative contributions to predictions; (2) partial methods on the predictor set to control variance inflation; and (3) diagnostics for LTRMP design elements that may influence model fits. Models were fit for 28 species, representing 3 habitat guilds (Lentic, Lotic, and Generalist). We intended to develop “systemic models” using data from all six LTRMP study reaches simultaneously; however, this proved impossible. Thus, we “regionalized” the models, creating two models for each species: “Upper Reach” models, using data from Pools 4, 8, and 13; and “Lower Reach” models, using data from Pool 26, the Open River Reach of the Mississippi River, and the La Grange reach of the Illinois River. A total of 56 models were attempted. For any given site-scale prediction, each model used data from the three LTRMP study reaches comprising the regional model to make predictions. For example, a site-scale prediction in Pool 8 was made using data from Pools 4, 8, and 13. This is the fundamental nature and trade-off of regionalizing these models for broad management application. Model fits were deemed “certifiably good” using the Hosmer and Lemeshow Goodness-of-Fit statistic (Hosmer and Lemeshow, 2000). This test post-partitions model predictions into 10 groups and conducts inferential tests on correspondences between observed and expected probability of occurrence across all partitions, under Chi-square distributional assumptions. This permits an inferential test of how well the models fit and a tool for reporting when they did not (and perhaps why). Our goal was to develop regionalized models, and to assess and describe circumstances when a good fit was not possible. Seven fish species composed the Lentic guild. Good fits were achieved for six Upper Reach models. In the Lower Reach, no model produced good fits for the Lentic guild. This was due to (1) lentic species being much less prominent in the Lower Reach study areas, and (2) those that do express greater prominence principally do so only in the La Grange reach of the Illinois River. Thus, developing Lower Reach models for Lentic species will require parsing La Grange from the other two Lower Reach study areas and fitting separate models. We did not do that as part of this study, but it could be done at a later time. Nine species comprised the Lotic guild. Good fits were achieved for seven Upper Reach models and six Lower Reach models. Four species had good fits for both regions (flathead catfish, blue sucker, sauger, and shorthead redhorse). Three species showed zoogeographic zonation, with a good model fit in one of the regions, but not in the region in which they were absent or rarely occurred (blue catfish, rock bass, and skipjack herring). Twelve species comprised the Generalist guild. Good fits were achieved for five Upper Reach models and eight Lower Reach models. Six species had good fits for both regions (brook silverside, emerald shiner, freshwater drum, logperch, longnose gar, and white bass). Two species showed zoogeographic zonation, with a good model fit in one of the regions, but not in the region in which they were absent or rarely occurred (red shiner and blackstripe topminnow). Poorly fit models were almost always due to the diagnostic variable “field station,” a surrogate for river mile. In these circumstances, the residuals for “field station” were non-randomly distributed and often strongly ordered. This indicates either fitting “pool scale” models for these species and regions, or explicitly model covariances between “field station” and the other predictors within the existing modeling framework. Further efforts on these models should seek to resolve these issues using one of these two approaches. In total, nine species, representing two of the three guilds (Lotic and Generalist), produced well-fit models for both regions. These nine species should comprise the basis for AHAG 2.0. Additional work, likely requiring downscaling of the regional models to pool-scale models, will be needed to incorporate additional species. Alternately, a regionalized AHAG could be comprised of those species, per region, that achieved well-fit models. The number of species and the composition of the regional species pools will differ among regions as a consequence. Each of these alternatives has both pros and cons, and managers are encouraged to consider them fully before further advancing this approach to modeling multi-species habitat suitability.

The self-transcendence scale: an investigation of the factor structure among nursing home patients.

PubMed

Haugan, Gørill; Rannestad, Toril; Garåsen, Helge; Hammervold, Randi; Espnes, Geir Arild

2012-09-01

Self-transcendence, the ability to expand personal boundaries in multiple ways, has been found to provide well-being. The purpose of this study was to examine the dimensionality of the Norwegian version of the Self-Transcendence Scale, which comprises 15 items. Reed's empirical nursing theory of self-transcendence provided the theoretical framework; self-transcendence includes an interpersonal, intrapersonal, transpersonal, and temporal dimension. Cross-sectional data were obtained from a sample of 202 cognitively intact elderly patients in 44 Norwegian nursing homes. Exploratory factor analysis revealed two and four internally consistent dimensions of self-transcendence, explaining 35.3% (two factors) and 50.7% (four factors) of the variance, respectively. Confirmatory factor analysis indicated that the hypothesized two- and four-factor models fitted better than the one-factor model (cx (2), root mean square error of approximation, standardized root mean square residual, normed fit index, nonnormed fit index, comparative fit index, goodness-of-fit index, and adjusted goodness-of-fit index). The findings indicate self-transcendence as a multifactorial construct; at present, we conclude that the two-factor model might be the most accurate and reasonable measure of self-transcendence. This research generates insights in the application of the widely used Self-Transcendence Scale by investigating its psychometric properties by applying a confirmatory factor analysis. It also generates new research-questions on the associations between self-transcendence and well-being.

Using the Theory of Planned Behavior to Understand Cervical Cancer Screening Among Latinas.

PubMed

Roncancio, Angelica M; Ward, Kristy K; Sanchez, Ingrid A; Cano, Miguel A; Byrd, Theresa L; Vernon, Sally W; Fernandez-Esquer, Maria Eugenia; Fernandez, Maria E

2015-10-01

To reduce the high incidence of cervical cancer among Latinas in the United States it is important to understand factors that predict screening behavior. The aim of this study was to test the utility of theory of planned behavior in predicting cervical cancer screening among a group of Latinas. A sample of Latinas (N = 614) completed a baseline survey about Pap test attitudes subjective norms, perceived behavioral control, and intention to be screened for cervical cancer. At 6 months postbaseline, cervical cancer screening behavior was assessed. Structural equation modeling was used to test the theory. Model fit statistics indicated good model fit: χ(2)(48) = 54.32, p = .246; comparative fit index = .992; root mean square error of approximation = .015; weighted root mean square residual = .687. Subjective norms (p = .005) and perceived behavioral control (p < .0001) were positively associated with intention to be screened for cervical cancer, and the intention to be screened predicted actual cervical cancer screening (p < .0001). The proportion of variance (R2) in intention accounted for by the predictors was .276 and the R2 in cervical cancer screening accounted for was .130. This study provides support for the use of the theory of planned behavior in predicting cervical cancer screening among Latinas. This knowledge can be used to inform the development of a theory of planned behavior-based intervention to increase cervical cancer screening among Latinas and reduce the high incidence of cervical cancer in this group of women. © 2015 Society for Public Health Education.

A Ray of Light: A Mixed-Methods Approach to Understanding Why Parents Choose Montessori Education

ERIC Educational Resources Information Center

Zarybnisky, Emily M.

2010-01-01

This study explored why parents choose Montessori schools for their children. Parents from two public (n = 40) and two private (n = 10) Montessori schools responded to a written survey designed to discern what characteristics parents valued in making their decision. Descriptive statistics, t-tests, and chi-square tests were used to understand the…

Evaluating the validity of the Work Role Functioning Questionnaire (Canadian French version) using classical test theory and item response theory.

PubMed

Hong, Quan Nha; Coutu, Marie-France; Berbiche, Djamal

2017-01-01

The Work Role Functioning Questionnaire (WRFQ) was developed to assess workers' perceived ability to perform job demands and is used to monitor presenteeism. Still few studies on its validity can be found in the literature. The purpose of this study was to assess the items and factorial composition of the Canadian French version of the WRFQ (WRFQ-CF). Two measurement approaches were used to test the WRFQ-CF: Classical Test Theory (CTT) and non-parametric Item Response Theory (IRT). A total of 352 completed questionnaires were analyzed. A four-factor and three-factor model models were tested and shown respectively good fit with 14 items (Root Mean Square Error of Approximation (RMSEA) = 0.06, Standardized Root Mean Square Residual (SRMR) = 0.04, Bentler Comparative Fit Index (CFI) = 0.98) and with 17 items (RMSEA = 0.059, SRMR = 0.048, CFI = 0.98). Using IRT, 13 problematic items were identified, of which 9 were common with CTT. This study tested different models with fewer problematic items found in a three-factor model. Using a non-parametric IRT and CTT for item purification gave complementary results. IRT is still scarcely used and can be an interesting alternative method to enhance the quality of a measurement instrument. More studies are needed on the WRFQ-CF to refine its items and factorial composition.

Curve fitting methods for solar radiation data modeling

NASA Astrophysics Data System (ADS)

Karim, Samsul Ariffin Abdul; Singh, Balbir Singh Mahinder

2014-10-01

This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R2. The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods.

Curve fitting methods for solar radiation data modeling

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

Karim, Samsul Ariffin Abdul, E-mail: samsul-ariffin@petronas.com.my, E-mail: balbir@petronas.com.my; Singh, Balbir Singh Mahinder, E-mail: samsul-ariffin@petronas.com.my, E-mail: balbir@petronas.com.my

2014-10-24

This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R{sup 2}. The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both withmore » two terms) gives better results as compare with the other fitting methods.« less

Psychometric properties of the Spanish version of the Resilience Scale.

PubMed

Heilemann, MarySue V; Lee, Kathryn; Kury, Felix Salvador

2003-01-01

The purpose of this study is to test the reliability and validity of a Spanish translation of the Resilience Scale (RS), which was originally created in English by Wagnild and Young (1993). A team of bilingual, bicultural translators participated in the translation process to enhance the linguistic accuracy and cultural appropriateness of the Spanish translation. As part of the convenience sample of 315 women of Mexican descent who participated in the larger study, data from 147 women who preferred to read and write in Spanish were used in this analysis. The English version of the RS consists of a 17-item "Personal Competence" subscale and an 8-item "Acceptance of Self and Life" subscale for a total of 25 items. However, two items had low item-total loadings and were removed to form a modified 23-item RS. The exploratory principal components factor analysis, varimax rotation, and subsequent goodness of fit indices were ambivalent on whether a one or two-factor solution was appropriate, but the chi-square difference test clearly demonstrated that the two-factor solution of the Spanish version was more useful in explaining variance than a one-factor solution. Internal consistency reliability was estimated with Cronbach's alpha (alpha = 0.93) which was acceptable for the 23-item RS as well as its subscales. Construct validity was demonstrated by a significant positive correlation between resilience and life satisfaction (r = 0.36; p < 0.001), and a significant negative correlation between resilience and depressive symptoms (r = -0.29; p < 0.01). This analysis ultimately supports the appropriateness of the modified 23-item Spanish translation of the RS and its subscales in a sample of urban, low-income women of Mexican descent in the U.S.

LC-PROM: Validation of a patient reported outcomes measure for liver cirrhosis patients.

PubMed

Zhang, Ying; Yang, Yuanyuan; Lv, Jing; Zhang, Yanbo

2016-05-10

The aim of the study is to develop a specific patient-reported scale of liver cirrhosis according to the Patient Reported Outcome guidelines of the Food and Drug Administration (FDA), and to examine its capacity to fill gaps in this field. A conceptual framework was developed and a preliminary item pool developed through literature review and interviews of 10 patients with liver cirrhosis. With the preliminary items, we performed a pilot survey that included a cognitive test with patients and interviews with experts; the focus was on content and language of the scale. In the item selection stage, seven statistical methods including discrete trends method, discrimination analysis, exploratory factor analysis, Cronbach's α coefficient, correlation coefficient, test-retest reliability, Item-Response Theory were applied to survey data from 200 subjects (150 liver cirrhosis patients and 50 controls). This produced the preliminary Liver Cirrhosis Patient-reported Outcome Measure (LC-PROM). In the next stage, we conducted the survey with 620 subjects (500 patients and 120 controls) to validate reliability, validity and acceptability of this scale. The 55 items and 13 dimensions addressed four domains: physical, psychological, social, and therapeutic. Cronbach's α coefficients were 0.921 for the total scale; the confirmatory factor analysis, t-tests and ANOVA supported scale validity; the model fit index as Root Mean Square Error of Approximation (RMSEA), Root Mean Square Residual (RMR), Normed Fit Index (NFI), Non-Normed Fit Index (NNFI), Comparative Fit Index (CFI) and Incremental Fit Index (IFI) met the criterion generally. The acceptance ratio and response rate indicated good feasibility. This study developed an accurate and stable patient-reported outcome scale of liver cirrhosis, which is able to evaluate clinical effects effectively, is helpful to patients in recognizing their health condition, and contributes to clinical decision making both for patients and physicians. Additionally, the LC-PROM can perform as an ultimate assessment of medical and health care effects and can inform clinical trials of new drugs for liver cirrhosis.

The interns' learning assessment in obstetrics and gynecology department of Zahedan University of Medical Sciences.

PubMed

Roudbari, Masoud; Yaghmaei, Minoo

2007-09-01

One of the aims of management priorities in medical universities is the evaluation of learning in educational departments in order to prevent educational retardation and to improve the quality of education. The aim of this study was to evaluate the interns' learning in the obstetrics and gynecology (O&G) department at Zahedan University of Medical Sciences (ZUMS). The study was performed in ZUMS, Iran, in 2002-2003 on all interns at the O&G department, including 30 men and 40 women. For data collection, a questionnaire was used and included some questions regarding the common emergencies and diseases in O&G, together with different learning indicators such as reading, observation, hearing, management, and the capability of management. The data were analyzed using descriptive statistics, tables, t test, and chi-square test using the SPSS software. The mean percentages of learning indicators of observation, bedside teaching, supervised management, and personal management in the common emergencies and diseases of O&G in male interns were significantly lower than those in female interns. Also, the mean percentages of managing capabilities were 12% and 70.5% in common emergencies and 14.2% and 59.3% in common diseases for male and female interns, respectively. The chi-square test showed a significant difference between the mean percentages of the managing capabilities in male and female interns for the majority of the common emergencies and diseases. Also, the chi-square test revealed a significant relationship between the learning indicators and the interns' managing capabilities for common emergencies and diseases. Some learning indicators in the male interns were very low. This needs urgent improvement of the learning quality in the O&G department, especially for the male interns, particularly those who are supposed to work in the deprived areas of the country after graduation in the public service.

Cardiovascular risk and metabolic syndrome in obese youth enrolled in a multidisciplinary medical weight management program: implications of musculoskeletal pain, cardiorespiratory fitness, and health-related quality of life.

PubMed

Briggs, Matthew S; Spees, Colleen; Bout-Tabaku, Sharon; Taylor, Christopher A; Eneli, Ihuoma; Schmitt, Laura C

2015-04-01

Obese youth demonstrate the same obesity-associated morbidities observed in obese adults, including poor cardiorespiratory fitness, poor quality of life, and reports of musculoskeletal pain. The purposes of this study were to compare the prevalence of cardiovascular risk factors and evaluate the odds of metabolic syndrome in obese youth based on measures of cardiorespiratory fitness, quality of life, and pain. A medical chart review of 183 obese youth in a medical weight management program was conducted. Measures of cardiovascular risk and metabolic syndrome were recorded. Groups were categorized based on Progressive Aerobic Cardiovascular Endurance Run (PACER) score, Pediatric Quality of Life (PedsQL)-Physical Function score, PedsQL-Psychosocial Health score, and reports of musculoskeletal pain. Statistical analysis included independent t-tests, Mann-Whitney U-test, chi-squared test, and logistic regression. Thirty-three percent of the entire sample had C-reactive protein (CRP) levels >3.0 mg/dL and 30% were categorized as having metabolic syndrome. Patients with lower PACER scores demonstrated a greater prevalence of CRP levels >3.0 mg/dL versus those with higher PACER scores (45% vs. 12%; P=0.01). There were no other differences in the prevalence of cardiovascular risk factors or metabolic syndrome when categorized by PACER, PedsQL, or pain. Those with CRP levels >3.0 mg/dL demonstrated increased odds of metabolic syndrome-[odds (95% confidence interval, CI): 4.93 (1.24-19.61); P=0.02]. Overall, results do not show differences in cardiovascular risk in obese youth when categorized by PACER, PedsQL, or reports of MSK pain. Elevated CRP may be a useful predictor of metabolic syndrome in obese youth and warrants further investigation.

Evaluating flow cytometer performance with weighted quadratic least squares analysis of LED and multi-level bead data

PubMed Central

Parks, David R.; Khettabi, Faysal El; Chase, Eric; Hoffman, Robert A.; Perfetto, Stephen P.; Spidlen, Josef; Wood, James C.S.; Moore, Wayne A.; Brinkman, Ryan R.

2017-01-01

We developed a fully automated procedure for analyzing data from LED pulses and multi-level bead sets to evaluate backgrounds and photoelectron scales of cytometer fluorescence channels. The method improves on previous formulations by fitting a full quadratic model with appropriate weighting and by providing standard errors and peak residuals as well as the fitted parameters themselves. Here we describe the details of the methods and procedures involved and present a set of illustrations and test cases that demonstrate the consistency and reliability of the results. The automated analysis and fitting procedure is generally quite successful in providing good estimates of the Spe (statistical photoelectron) scales and backgrounds for all of the fluorescence channels on instruments with good linearity. The precision of the results obtained from LED data is almost always better than for multi-level bead data, but the bead procedure is easy to carry out and provides results good enough for most purposes. Including standard errors on the fitted parameters is important for understanding the uncertainty in the values of interest. The weighted residuals give information about how well the data fits the model, and particularly high residuals indicate bad data points. Known photoelectron scales and measurement channel backgrounds make it possible to estimate the precision of measurements at different signal levels and the effects of compensated spectral overlap on measurement quality. Combining this information with measurements of standard samples carrying dyes of biological interest, we can make accurate comparisons of dye sensitivity among different instruments. Our method is freely available through the R/Bioconductor package flowQB. PMID:28160404

Standardization and Prevalence of the Booster Phenomenon: Evaluation Using a Two-Step Skin Test with 43 kDa Glycoprotein in Individuals from an Endemic Region of Paracoccidioidomycosis.

PubMed

Marques, Ana Paula C; Oliveira, Sandra Maria V L; Rezende, Grazielli R; Melo, Dayane A; Fernandes-Fitts, Sonia M; Pontes, Elenir Rose J C; Bonecini-Almeida, Maria da Glória; Camargo, Zoilo P; Mendes, Rinaldo P; Paniago, Anamaria M M

2017-10-01

We estimated the occurrence rate of the booster phenomenon by using an intradermal test with 43 kDa glycoprotein in an endemic area of paracoccidioidomycosis in the central-west region of Brazil. Individuals who had a negative result on a survey performed by using an intradermal test with 43 kDa glycoprotein in an endemic area of paracoccidioidomycosis underwent a second intradermal test after 10-15 days to determine the presence or absence of the booster phenomenon. Statistical analyses were performed using the Chi-square test, Chi-square for linear trend test, Student's t test, and binomial test; p < 0.05 was considered significant. For the first time, we reported the occurrence of the booster phenomenon to an intradermal reaction caused by 43 kDa glycoprotein at a rate of 5.8-8.4%, depending on the test's cutoff point. This suggests that a cutoff point should be considered for the booster phenomenon in intradermal tests with 43 kDa glycoprotein: a difference of 6-7 mm between readings according to the first and second tests, depending on the purpose of the evaluation. The results indicate that the prevalence of paracoccidioidal infection in endemic areas is underestimated, as the booster phenomenon has not been considered in epidemiological surveys for this infection.

Genotyping and drug resistance patterns of M. tuberculosis strains in Pakistan

PubMed Central

Tanveer, Mahnaz; Hasan, Zahra; Siddiqui, Amna R; Ali, Asho; Kanji, Akbar; Ghebremicheal, Solomon; Hasan, Rumina

2008-01-01

Background The incidence of tuberculosis in Pakistan is 181/100,000 population. However, information about transmission and geographical prevalence of Mycobacterium tuberculosis strains and their evolutionary genetics as well as drug resistance remains limited. Our objective was to determine the clonal composition, evolutionary genetics and drug resistance of M. tuberculosis isolates from different regions of the country. Methods M. tuberculosis strains isolated (2003–2005) from specimens submitted to the laboratory through collection units nationwide were included. Drug susceptibility was performed and strains were spoligotyped. Results Of 926 M. tuberculosis strains studied, 721(78%) were grouped into 59 "shared types", while 205 (22%) were identified as "Orphan" spoligotypes. Amongst the predominant genotypes 61% were Central Asian strains (CAS ; including CAS1, CAS sub-families and Orphan Pak clusters), 4% East African-Indian (EAI), 3% Beijing, 2% poorly defined TB strains (T), 2% Haarlem and LAM (0.2). Also TbD1 analysis (M. tuberculosis specific deletion 1) confirmed that CAS1 was of "modern" origin while EAI isolates belonged to "ancestral" strain types. Prevalence of CAS1 clade was significantly higher in Punjab (P < 0.01, Pearsons Chi-square test) as compared with Sindh, North West Frontier Province and Balochistan provinces. Forty six percent of isolates were sensitive to five first line antibiotics tested, 45% were Rifampicin resistant, 50% isoniazid resistant. MDR was significantly associated with Beijing strains (P = 0.01, Pearsons Chi-square test) and EAI (P = 0.001, Pearsons Chi-square test), but not with CAS family. Conclusion Our results show variation of prevalent M. tuberculosis strain with greater association of CAS1 with the Punjab province. The fact that the prevalent CAS genotype was not associated with drug resistance is encouraging. It further suggests a more effective treatment and control programme should be successful in reducing the tuberculosis burden in Pakistan. PMID:19108722

Using permutations to detect dependence between time series

NASA Astrophysics Data System (ADS)

Cánovas, Jose S.; Guillamón, Antonio; Ruíz, María del Carmen

2011-07-01

In this paper, we propose an independence test between two time series which is based on permutations. The proposed test can be carried out by means of different common statistics such as Pearson’s chi-square or the likelihood ratio. We also point out why an exact test is necessary. Simulated and real data (return exchange rates between several currencies) reveal the capacity of this test to detect linear and nonlinear dependences.

Pre-Deployment Stress, Mental Health, and Help-Seeking Behaviors Among Marines

DTIC Science & Technology

2014-01-01

associations between two categori- cal variables, and Wald tests were conducted to compare mean scores on continuous variables across groups (e.g...Cluster- adjusted wald tests were conducted to determine whether there were significant differences by rank on the average number of potentially...deployed to Iraq or Afghanistan in 2010 or 2011 of rank O6 or lower. a Omnibus rao-Scott chi-square test or adjusted wald test is statistically

An alternative to traditional goodness-of-fit tests for discretely measured continuous data

Treesearch

KaDonna C. Randolph; Bill Seaver

2007-01-01

Traditional goodness-of-fit tests such as the Kolmogorov-Smirnov and x2 tests are easily applied to data of the continuous or discrete type, respectively. Occasionally, however, the case arises when continuous data are recorded into discrete categories due to an imprecise measurement system. In this instance, the traditional goodness-of-fit...

Effects of Linking Methods on Detection of DIF.

ERIC Educational Resources Information Center

Kim, Seock-Ho; Cohen, Allan S.

1992-01-01

Effects of the following methods for linking metrics on detection of differential item functioning (DIF) were compared: (1) test characteristic curve method (TCC); (2) weighted mean and sigma method; and (3) minimum chi-square method. With large samples, results were essentially the same. With small samples, TCC was most accurate. (SLD)

Interdependence of PRECIS Role Operators: A Quantitative Analysis of Their Associations.

ERIC Educational Resources Information Center

Mahapatra, Manoranjan; Biswas, Subal Chandra

1986-01-01

Analyzes associations among different role operators quantitatively by taking input strings from 200 abstracts, each related to subject fields of taxation, genetic psychology, and Shakespearean drama, and subjecting them to the Chi-square test. Significant associations by other differencing operators and connectives are discussed. A schema of role…

Genetic structure of populations and differentiation in forest trees

Treesearch

Raymond P. Guries; F. Thomas Ledig

1981-01-01

Electrophoretic techniques permit population biologists to analyze genetic structure of natural populations by using large numbers of allozyme loci. Several methods of analysis have been applied to allozyme data, including chi-square contingency tests, F-statistics, and genetic distance. This paper compares such statistics for pitch pine (Pinus rigida...

Availability of Vending Machines and School Stores in California Schools

ERIC Educational Resources Information Center

Cisse-Egbuonye, Nafissatou; Liles, Sandy; Schmitz, Katharine E.; Kassem, Nada; Irvin, Veronica L.; Hovell, Melbourne F.

2016-01-01

Background: This study examined the availability of foods sold in vending machines and school stores in United States public and private schools, and associations of availability with students' food purchases and consumption. Methods: Descriptive analyses, chi-square tests, and Spearman product-moment correlations were conducted on data collected…

Structural Model of psychological risk and protective factors affecting on quality of life in patients with coronary heart disease: A psychocardiology model

PubMed Central

Nekouei, Zohreh Khayyam; Yousefy, Alireza; Doost, Hamid Taher Neshat; Manshaee, Gholamreza; Sadeghei, Masoumeh

2014-01-01

Background: Conducted researches show that psychological factors may have a very important role in the etiology, continuity and consequences of coronary heart diseases. This study has drawn the psychological risk and protective factors and their effects in patients with coronary heart diseases (CHD) in a structural model. It aims to determine the structural relations between psychological risk and protective factors with quality of life in patients with coronary heart disease. Materials and Methods: The present cross-sectional and correlational studies were conducted using structural equation modeling. The study sample included 398 patients of coronary heart disease in the university referral Hospital, as well as other city health care centers in Isfahan city. They were selected based on random sampling method. Then, in case, they were executed the following questionnaires: Coping with stressful situations (CISS- 21), life orientation (LOT-10), general self-efficacy (GSE-10), depression, anxiety and stress (DASS-21), perceived stress (PSS-14), multidimensional social support (MSPSS-12), alexithymia (TAS-20), spiritual intelligence (SQ-23) and quality of life (WHOQOL-26). Results: The results showed that protective and risk factors could affect the quality of life in patients with CHD with factor loadings of 0.35 and −0.60, respectively. Moreover, based on the values of the framework of the model such as relative chi-square (CMIN/DF = 3.25), the Comparative Fit Index (CFI = 0.93), the Parsimony Comparative Fit Index (PCFI = 0.68), the Root Mean Square Error of Approximation (RMSEA = 0.07) and details of the model (significance of the relationships) it has been confirmed that the psychocardiological structural model of the study is the good fitting model. Conclusion: This study was among the first to research the different psychological risk and protective factors of coronary heart diseases in the form of a structural model. The results of this study have emphasized the necessity of noticing the psychological factors in primary prevention by preventive programs and in secondary prevention by rehabilitation centers to improve the quality of life of the people with heart diseases. PMID:24778660

[Confirmative study of a French version of the Exercise Dependence Scale-revised with a French population].

PubMed

Allegre, B; Therme, P

2008-10-01

Since the first writings on excessive exercise, there has been an increased interest in exercise dependence. One of the major consequences of this increased interest has been the development of several definitions and measures of exercise dependence. The work of Veale [Does primary exercise dependence really exist? In: Annet J, Cripps B, Steinberg H, editors. Exercise addiction: Motivation for participation in sport and exercise.Leicester, UK: Br Psychol Soc; 1995. p. 1-5.] provides an advance for the definition and measure of exercise dependence. These studies have adapted the DSM-IV criteria for substance dependence to measure exercise dependence. The Exercise Dependence Scale-Revised is based on these diagnostic criteria, which are: tolerance; withdrawal effects; intention effect; lack of control; time; reductions in other activities; continuance. Confirmatory factor analyses of EDS-R provided support to present a measurement model (21 items loaded in seven factors) of EDS-R (Comparative Fit Index=0.97; Root mean Square Error of Approximation=0.05; Tucker-Lewis Index=0.96). The aim of this study was to examine the psychometric properties of a French version of the EDS-R [Factorial validity and psychometric examination of the exercise dependence scale-revised. Meas Phys Educ Exerc Sci 2004;8(4):183-201.] to test the stability of the seven-factor model of the original version with a French population. A total of 516 half-marathoners ranged in age from 17 to 74 years old (Mean age=39.02 years, ET=10.64), with 402 men (77.9%) and 114 women (22.1%) participated in the study. The principal component analysis results in a six-factor structure, which accounts for 68.60% of the total variance. Because principal component analysis presents a six-factor structure differing from the original seven-factor structure, two models were tested, using confirmatory factor analysis. The first model is the seven-factor model of the original version of the EDS-R and the second is the model produced by the principal component analysis. The results of confirmatory factor analysis presented the original model (with a seven-factor structure) as a good model and fit indices were good (X(2)/ddl=2.89, Root Mean Square Error of Approximation (RMSEA)=0.061, Expected Cross Validation Index (ECVI)=1.20, Goodness-of-Fit Index (GFI)=0.92, Comparative Fit Index (CFI)=0.94, Standardized Root Mean Square (SRMS)=0.048). These results showed that the French version of EDS-R has an identical factor structure to the original. Therefore, the French version of EDS-R was an acceptable scale to measure exercise dependence and can be used on a French population.

What Do Teachers Need to Support English Learners?

ERIC Educational Resources Information Center

Gomez, Marjorie N.; Diarrassouba, Nagnon

2014-01-01

This study explored K-8 teachers' perceptions of their preparation and the challenges they encountered in delivering instruction to culturally and linguistically diverse learners. Using a mixed method research design, data were collected through a web-based survey from teachers in the state of Michigan. Researchers used chi-square tests to…

Public Opinion toward Sexuality Education: Findings among One South Florida County

ERIC Educational Resources Information Center

Howard-Barr, Elissa; Moore, Michele Johnson; Weiss, Josie A.; Jobli, Edessa

2011-01-01

As part of a community plan to implement abstinence-based sexuality education, this study assessed opinions toward sexuality education among residents. Respondents (N = 1,090) were selected by random digit dialing. The survey, adopted from previous national studies, assessed attitudes towards sexuality education. Chi-square tests of significance…

A validated model for the 22-item Sino-Nasal Outcome Test subdomain structure in chronic rhinosinusitis.

PubMed

Feng, Allen L; Wesely, Nicholas C; Hoehle, Lloyd P; Phillips, Katie M; Yamasaki, Alisa; Campbell, Adam P; Gregorio, Luciano L; Killeen, Thomas E; Caradonna, David S; Meier, Josh C; Gray, Stacey T; Sedaghat, Ahmad R

2017-12-01

Previous studies have identified subdomains of the 22-item Sino-Nasal Outcome Test (SNOT-22), reflecting distinct and largely independent categories of chronic rhinosinusitis (CRS) symptoms. However, no study has validated the subdomain structure of the SNOT-22. This study aims to validate the existence of underlying symptom subdomains of the SNOT-22 using confirmatory factor analysis (CFA) and to develop a subdomain model that practitioners and researchers can use to describe CRS symptomatology. A total of 800 patients with CRS were included into this cross-sectional study (400 CRS patients from Boston, MA, and 400 CRS patients from Reno, NV). Their SNOT-22 responses were analyzed using exploratory factor analysis (EFA) to determine the number of symptom subdomains. A CFA was performed to develop a validated measurement model for the underlying SNOT-22 subdomains along with various tests of validity and goodness of fit. EFA demonstrated 4 distinct factors reflecting: sleep, nasal, otologic/facial pain, and emotional symptoms (Cronbach's alpha, >0.7; Bartlett's test of sphericity, p < 0.001; Kaiser-Meyer-Olkin >0.90), independent of geographic locale. The corresponding CFA measurement model demonstrated excellent measures of fit (root mean square error of approximation, <0.06; standardized root mean square residual, <0.08; comparative fit index, >0.95; Tucker-Lewis index, >0.95) and measures of construct validity (heterotrait-monotrait [HTMT] ratio, <0.85; composite reliability, >0.7), again independent of geographic locale. The use of the 4-subdomain structure for SNOT-22 (reflecting sleep, nasal, otologic/facial pain, and emotional symptoms of CRS) was validated as the most appropriate to calculate SNOT-22 subdomain scores for patients from different geographic regions using CFA. © 2017 ARS-AAOA, LLC.

Factors affecting pharmacy engagement and pharmacy customer devotion in community pharmacy: A structural equation modeling approach

PubMed Central

Nitadpakorn, Sujin; Kittisopee, Tanattha

2017-01-01

Background: The concept of customer engagement and devotion has been applied in various service businesses to keep the customers with business However, a limited number of studies were performed to examine the context of customer engagement and devotion in pharmacy business which focus on the impact of customer perceptions about pharmacists, perceived quality of pharmacy structure, medication price strategy on pharmacy engagement and pharmacy customer devotion in a pharmacy providing pharmaceutical care to the customers. Objective: This study aimed to assess a conceptual model depicting the relationships among customer perceptions about pharmacists, pharmacy quality structure, medication price, customer engagement, and customer devotion. And also aimed to assess and measure if there is a direct or indirect relationship between these factors. Methods: A quantitative study was conducted by using self-administered questionnaires. Two hundred and fifty three customers who regularly visited the pharmacy were randomly recruited from a purposively selected 30 community pharmacies in Bangkok. The survey was completed during February to April 2016. A structural equation model (SEM) was used to assess the direct and indirect relationships between constructs. Results: A total of 253/300 questionnaires were returned for analysis, and the response rate was 84%. Only perceptions about pharmacist in customers receiving professional pharmacy services was statically significant regarding relationship with pharmacy engagement (beta=0.45). Concurrently, the model from empirical data fit with the hypothetical model (p-value = 0.06, adjusted chi-square (CMIN/DF)=1.16, Goodness of Fit Index (GFI)=0.93, Comparatively Fit Index (CFI)=0.99, and Root Mean Square Error Approximation (RMSEA)=0.03). Conclusion: The study confirmed the indirect positive influence of customer perceptions about pharmacist on pharmacy customer devotion in providing pharmacy services via pharmacy engagement It was customer perceptions about pharmacist that influenced customer retention, positive word of mouth and constructive advice to pharmacies, not quality of pharmacy structure and medication price. To create a long term impact on community pharmacy business, pharmacist is the key success factor. PMID:28943984

New Software for Market Segmentation Analysis: A Chi-Square Interaction Detector. AIR 1983 Annual Forum Paper.

ERIC Educational Resources Information Center

Lay, Robert S.

The advantages and disadvantages of new software for market segmentation analysis are discussed, and the application of this new, chi-square based procedure (CHAID), is illustrated. A comparison is presented of an earlier, binary segmentation technique (THAID) and a multiple discriminant analysis. It is suggested that CHAID is superior to earlier…

The Blind Men and the Elephant: Identification of a Latent Maltreatment Construct for Youth in Foster Care

PubMed Central

Gabrielli, Joy; Jackson, Yo; Tunno, Angela M.; Hambrick, Erin P.

2017-01-01

Child maltreatment is a major public health concern due to its impact on developmental trajectories and consequences across mental and physical health outcomes. Operationalization of child maltreatment has been complicated, as research has used simple dichotomous counts to identification of latent class profiles. This study examines a latent measurement model assessed within foster youth inclusive of indicators of maltreatment chronicity and severity across four maltreatment types: physical, sexual, and psychological abuse, and neglect. Participants were 500 foster youth with a mean age of 12.99 years (SD = 2.95 years). Youth completed survey questions through a confidential audio computer-assisted self-interview program. A two-factor model with latent constructs of chronicity and severity of maltreatment revealed excellent fit across fit indices; however, the latent constructs were correlated .972. A one-factor model also demonstrated excellent model fit to the data (χ2 (16, n = 500) =28.087, p =.031, RMSEA (0.012 – 0.062) =.039, TLI =.990, CFI =.994, SRMR =.025) with a nonsignificant chi-square difference test comparing the one- and two-factor models. Invariance tests across age, gender, and placement type also were conducted with recommendations provided. Results suggest a single-factor latent model of maltreatment severity and chronicity can be attained. Thus, the maltreatment experiences reported by foster youth, though varied and complex, were captured in a model that may prove useful in later predictions of outcome behaviors. Appropriate identification of both the chronicity and severity of maltreatment inclusive of the range of maltreatment types remains a high priority for future research. PMID:28254690

The relationship of attitude, subjective norm, and behavioral intent to the documentation behavior of nurses.

PubMed

Renfroe, D H; O'Sullivan, P S; McGee, G W

1990-01-01

Ajzen and Fishbein's theory of reasoned action was used to assess the relationship of nurses' attitude, subjective norm, and behavioral intention to their documentation behavior. Attitudes, subjective norms, and behavioral intentions toward documentation were elicited from 108 staff nurses. Documentation behavior was based on what should be documented in any hospitalized patient's chart during a shift. This exploratory model was analyzed with LISREL VI. The overall fit of the final model to the data was good, as judged by a chi-square (df = 7, p = .845). The total coefficient of determination for the structural equation was .461. Attitude toward documentation did not relate significantly to intention to document optimally. Subjective norm did have a significant effect on behavioral intent. Attitude and subjective norm accounted for 46.1% of the variance in behavioral intent. Behavioral intent had a significant effect on documentation behavior, accounting for 15.2% of the variance. It appears that subjective norm, which is the influence of others, is what directs the intention to document and thus relates to subsequent documentation. Recommendations for practice include the communication of high ideals and expectations of important others to the staff nurse in order to improve the quality of documentation.

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

PubMed

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

2015-09-01

Can we build and validate predictive models for ovulation and pregnancy outcomes in infertile women with polycystic ovary syndrome (PCOS)? We were able to develop and validate a predictive model for pregnancy outcomes in women with PCOS using simple clinical and biochemical criteria particularly duration of attempting conception, which was the most consistent predictor among all considered factors for pregnancy outcomes. Predictive models for ovulation and pregnancy outcomes in infertile women with polycystic ovary syndrome have been reported, but such models require validation. This is a secondary analysis of the data from the Pregnancy in Polycystic Ovary Syndrome I and II (PPCOS-I and -II) trials. Both trials were double-blind, randomized clinical trials that included 626 and 750 infertile women with PCOS, respectively. PPCOS-I participants were randomized to either clomiphene citrate (CC), metformin, or their combination, and PPCOS-II participants to either letrozole or CC for up to five treatment cycles. Linear logistic regression models were fitted using treatment, BMI, and other published variables as predictors of ovulation, conception, clinical pregnancy, and live birth as the outcome one at a time. We first evaluated previously reported significant predictors, and then constructed new prediction models. Receiver operating characteristic (ROC) curves were constructed and the area under the curves (AUCs) was calculated to compare performance using different models and data. Chi-square tests were used to examine the goodness-of-fit and prediction power of logistic regression model. Predictive factors were similar between PPCOS-I and II, but the two participant samples differed statistically significantly but the differences were clinically minor on key baseline characteristics and hormone levels. Women in PPCOS-II had an overall more severe PCOS phenotype than women in PPCOS-I. The clinically minor but statistically significant differences may be due to the large sample sizes. Younger age, lower baseline free androgen index and insulin, shorter duration of attempting conception, and higher baseline sex hormone-binding globulin significantly predicted at least one pregnancy outcome. The ROC curves (with AUCs of 0.66-0.76) and calibration plots and chi-square tests indicated stable predictive power of the identified variables (P-values ≥0.07 for all goodness-of-fit and validation tests). This is a secondary analysis. Although our primary objective was to confirm previously reported results and identify new predictors of ovulation and pregnancy outcomes among PPCOS-II participants, our approach is exploratory and warrants further replication. We have largely confirmed the predictors that were identified in the PPCOS-I trial. However, we have also revealed new predictors, particularly the role of smoking. While a history of ever smoking was not a significant predictor for live birth, a closer look at current, quit, and never smoking revealed that current smoking was a significant risk factor. The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Grants U10 HD27049, U10 HD38992, U10HD055925, U10 HD39005, U10 HD33172, U10 HD38998, U10 HD055936, U10 HD055942, and U10 HD055944; and U54-HD29834. Heilongjiang University of Chinese Medicine Grants 051277 and B201005. R.S.L. reports receiving consulting fees from Euroscreen, AstraZeneca, Clarus Therapeutics, and Takeda, and grant support from Ferring, Astra Zeneca, and Toba. K.R.H. reports receiving grant support from Roche Diagnostics and Ferring Pharmascience. G.C. reports receiving Honorarium and grant support from Abbvie Pharmaceuticals and Bayer Pharmaceuticals. M.P.D. holds equity from Advanced Reproductive Care Inc. and DS Biotech, receives fees from Advanced Reproductive Care Inc., Actamax, Auxogyn, ZSX Medical, Halt Medical, and Neomed, and receives grant support from Boehringer-Ingelheim, Abbott, and BioSante, Ferring Pharmaceuticals, and EMD Serono. H.Z. receives research support from the Chinese 1000-scholar plan. Others report no disclosures other than NIH grant support. PPCOS-I and -II were respectively registered at Clinicaltrials.gov: NCT00719186 and NCT00719186. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The healthy diver: A cross-sectional survey to evaluate the health status of recreational scuba diver members of Divers Alert Network (DAN).

PubMed

Ranapurwala, Shabbar I; Kucera, Kristen L; Denoble, Petar J

2018-01-01

Scuba diver fitness is paramount to confront environmental stressors of diving. However, the diving population is aging and the increasing prevalence of diseases may be a concern for diver fitness. The purpose of this study is to assess the demographics, lifestyle factors, disease prevalence, and healthcare access and utilization of Divers Alert Network (DAN) members and compare them with those from the general population. DAN membership health survey (DMHS) was administered online in 2011 to DAN members in the United States (US). Health status of DMHS respondents was compared with the general US population data from the Center for Disease Control and Prevention's Behavioral Risk Factor Surveillance System using two-sided student's t-tests and Mantel-Haenszel chi-square tests. Univariate and multivariate logistic regression analyses were conducted to identify factors associated with healthcare utilization among the DMHS participants. Compared to the general US population, the DMHS population had lower prevalence of asthma, heart attack, angina, stroke, diabetes, hypertension, hypercholesterolemia, and disabilities (p<0.01); more heavy alcohol drinkers, and fewer smokers (p<0.01); and greater access and utilization (routine checkup) of healthcare (p<0.01). Healthcare utilization in males was lower than among females. Increasing age and increase in the number of chronic illnesses were associated with increased healthcare utilization. DAN members are healthier than the general US population. DAN members also have better access to healthcare and utilize healthcare for preventive purposes more often than the general population. DAN members appear to have a better fitness level than their non-diving peers.

The distance function effect on k-nearest neighbor classification for medical datasets.

PubMed

Hu, Li-Yu; Huang, Min-Wei; Ke, Shih-Wen; Tsai, Chih-Fong

2016-01-01

K-nearest neighbor (k-NN) classification is conventional non-parametric classifier, which has been used as the baseline classifier in many pattern classification problems. It is based on measuring the distances between the test data and each of the training data to decide the final classification output. Since the Euclidean distance function is the most widely used distance metric in k-NN, no study examines the classification performance of k-NN by different distance functions, especially for various medical domain problems. Therefore, the aim of this paper is to investigate whether the distance function can affect the k-NN performance over different medical datasets. Our experiments are based on three different types of medical datasets containing categorical, numerical, and mixed types of data and four different distance functions including Euclidean, cosine, Chi square, and Minkowsky are used during k-NN classification individually. The experimental results show that using the Chi square distance function is the best choice for the three different types of datasets. However, using the cosine and Euclidean (and Minkowsky) distance function perform the worst over the mixed type of datasets. In this paper, we demonstrate that the chosen distance function can affect the classification accuracy of the k-NN classifier. For the medical domain datasets including the categorical, numerical, and mixed types of data, K-NN based on the Chi square distance function performs the best.

Comparison of the multiple mini-interview with the traditional interview for U.S. emergency medicine residency applicants: a single-institution experience.

PubMed

Soares, William E; Sohoni, Aparajita; Hern, Herbert G; Wills, Charlotte P; Alter, Harrison J; Simon, Barry C

2015-01-01

The multiple mini-interview (MMI) is a validated interview technique used primarily to evaluate medical school applicants. No study has compared MMIs with traditional interviews (TIs) in the evaluation of U.S. emergency medicine residency (EMR) applicants. During the 2011-2012 interview season, a four-station MMI was incorporated into the interview process for EMR applicants at Alameda Health System-Highland Hospital (AHS). A postinterview anonymous questionnaire was offered to all applicants after they submitted their rank lists but prior to release of National Residency Matching Program results. Respondents rated their perceptions of the MMI and TI on a five-point Likert scale. McNemar chi-square test was used to explore differences in respondents' perceptions of interview styles. One hundred ten interviewees completed the survey (73%). Overall, applicants found the TI more enjoyable than the MMI process (98 [89%] compared with 48 [44%], McNemar chi-square=28.66, P<.01) and preferred the TI process to the MMI (66 [60%] compared with 9 [10%], McNemar chi-square=40.81, P<.01). Sixteen applicants (14%) indicated that the use of the MMI would negatively affect their ranking of the program. In contrast to prior studies, U.S. EMR applicants to AHS preferred the TI to the MMI. Further investigation into the use of the MMI for selecting U.S. EMR applicants is warranted.

Computer user's manual for a generalized curve fit and plotting program

NASA Technical Reports Server (NTRS)

Schlagheck, R. A.; Beadle, B. D., II; Dolerhie, B. D., Jr.; Owen, J. W.

1973-01-01

A FORTRAN coded program has been developed for generating plotted output graphs on 8-1/2 by 11-inch paper. The program is designed to be used by engineers, scientists, and non-programming personnel on any IBM 1130 system that includes a 1627 plotter. The program has been written to provide a fast and efficient method of displaying plotted data without having to generate any additions. Various output options are available to the program user for displaying data in four different types of formatted plots. These options include discrete linear, continuous, and histogram graphical outputs. The manual contains information about the use and operation of this program. A mathematical description of the least squares goodness of fit test is presented. A program listing is also included.

Improvement of Raman lidar algorithm for quantifying aerosol extinction

NASA Technical Reports Server (NTRS)

Russo, Felicita; Whiteman, David; Demoz, Belay; Hoff, Raymond

2005-01-01

Aerosols are particles of different composition and origin and influence the formation of clouds which are important in atmospheric radiative balance. At the present there is high uncertainty on the effect of aerosols on climate and this is mainly due to the fact that aerosol presence in the atmosphere can be highly variable in space and time. Monitoring of the aerosols in the atmosphere is necessary to better understanding many of these uncertainties. A lidar (an instrument that uses light to detect the extent of atmospheric aerosol loading) can be particularly useful to monitor aerosols in the atmosphere since it is capable to record the scattered intensity as a function of altitude from molecules and aerosols. One lidar method (the Raman lidar) makes use of the different wavelength changes that occur when light interacts with the varying chemistry and structure of atmospheric aerosols. One quantity that is indicative of aerosol presence is the aerosol extinction which quantifies the amount of attenuation (removal of photons), due to scattering, that light undergoes when propagating in the atmosphere. It can be directly measured with a Raman lidar using the wavelength dependence of the received signal. In order to calculate aerosol extinction from Raman scattering data it is necessary to evaluate the rate of change (derivative) of a Raman signal with respect to altitude. Since derivatives are defined for continuous functions, they cannot be performed directly on the experimental data which are not continuous. The most popular technique to find the functional behavior of experimental data is the least-square fit. This procedure allows finding a polynomial function which better approximate the experimental data. The typical approach in the lidar community is to make an a priori assumption about the functional behavior of the data in order to calculate the derivative. It has been shown in previous work that the use of the chi-square technique to determine the most likely functional behavior of the data prior to actually calculating the derivative eliminates the need for making a priori assumptions. We note that the a priori choice of a model itself can lead to larger uncertainties as compared to the method that is validated here. In this manuscript, the chi-square technique that determines the most likely functional behavior is validated through numerical simulation and by application to a large body of Raman lidar measurements. In general, we show that the chi-square approach to evaluate aerosol extinction yields lower extinction uncertainty than the traditional technique. We also use the technique to study the feasibility of developing a general characterization of the extinction uncertainty that could permit the uncertainty in Raman lidar aerosol extinction measurements to be estimated accurately without the use of the chi-square technique.

Quantitative photoplethysmography: Lambert-Beer law or inverse function incorporating light scatter.

PubMed

Cejnar, M; Kobler, H; Hunyor, S N

1993-03-01

Finger blood volume is commonly determined from measurement of infra-red (IR) light transmittance using the Lambert-Beer law of light absorption derived for use in non-scattering media, even when such transmission involves light scatter around the phalangeal bone. Simultaneous IR transmittance and finger volume were measured over the full dynamic range of vascular volumes in seven subjects and outcomes compared with data fitted according to the Lambert-Beer exponential function and an inverse function derived for light attenuation by scattering materials. Curves were fitted by the least-squares method and goodness of fit was compared using standard errors of estimate (SEE). The inverse function gave a better data fit in six of the subjects: mean SEE 1.9 (SD 0.7, range 0.7-2.8) and 4.6 (2.2, 2.0-8.0) respectively (p < 0.02, paired t-test). Thus, when relating IR transmittance to blood volume, as occurs in the finger during measurements of arterial compliance, an inverse function derived from a model of light attenuation by scattering media gives more accurate results than the traditional exponential fit.

Validation of a pre-existing safety climate scale for the Turkish furniture manufacturing industry.

PubMed

Akyuz, Kadri Cemil; Yildirim, Ibrahim; Gungor, Celal

2018-03-22

Understanding the safety climate level is essential to implement a proactive safety program. The objective of this study is to explore the possibility of having a safety climate scale for the Turkish furniture manufacturing industry since there has not been any scale available. The questionnaire recruited 783 subjects. Confirmatory factor analysis (CFA) tested a pre-existing safety scale's fit to the industry. The CFA indicated that the structures of the model present a non-satisfactory fit with the data (χ 2  = 2033.4, df = 314, p ≤ 0.001; root mean square error of approximation = 0.08, normed fit index = 0.65, Tucker-Lewis index = 0.65, comparative fit index = 0.69, parsimony goodness-of-fit index = 0.68). The results suggest that a new scale should be developed and validated to measure the safety climate level in the Turkish furniture manufacturing industry. Due to the hierarchical structure of organizations, future studies should consider a multilevel approach in their exploratory factor analyses while developing a new scale.

Testing goodness of fit in regression: a general approach for specified alternatives.

PubMed

Solari, Aldo; le Cessie, Saskia; Goeman, Jelle J

2012-12-10

When fitting generalized linear models or the Cox proportional hazards model, it is important to have tools to test for lack of fit. Because lack of fit comes in all shapes and sizes, distinguishing among different types of lack of fit is of practical importance. We argue that an adequate diagnosis of lack of fit requires a specified alternative model. Such specification identifies the type of lack of fit the test is directed against so that if we reject the null hypothesis, we know the direction of the departure from the model. The goodness-of-fit approach of this paper allows to treat different types of lack of fit within a unified general framework and to consider many existing tests as special cases. Connections with penalized likelihood and random effects are discussed, and the application of the proposed approach is illustrated with medical examples. Tailored functions for goodness-of-fit testing have been implemented in the R package global test. Copyright © 2012 John Wiley & Sons, Ltd.

Use of Selected Goodness-of-Fit Statistics to Assess the Accuracy of a Model of Henry Hagg Lake, Oregon

NASA Astrophysics Data System (ADS)

Rounds, S. A.; Sullivan, A. B.

2004-12-01

Assessing a model's ability to reproduce field data is a critical step in the modeling process. For any model, some method of determining goodness-of-fit to measured data is needed to aid in calibration and to evaluate model performance. Visualizations and graphical comparisons of model output are an excellent way to begin that assessment. At some point, however, model performance must be quantified. Goodness-of-fit statistics, including the mean error (ME), mean absolute error (MAE), root mean square error, and coefficient of determination, typically are used to measure model accuracy. Statistical tools such as the sign test or Wilcoxon test can be used to test for model bias. The runs test can detect phase errors in simulated time series. Each statistic is useful, but each has its limitations. None provides a complete quantification of model accuracy. In this study, a suite of goodness-of-fit statistics was applied to a model of Henry Hagg Lake in northwest Oregon. Hagg Lake is a man-made reservoir on Scoggins Creek, a tributary to the Tualatin River. Located on the west side of the Portland metropolitan area, the Tualatin Basin is home to more than 450,000 people. Stored water in Hagg Lake helps to meet the agricultural and municipal water needs of that population. Future water demands have caused water managers to plan for a potential expansion of Hagg Lake, doubling its storage to roughly 115,000 acre-feet. A model of the lake was constructed to evaluate the lake's water quality and estimate how that quality might change after raising the dam. The laterally averaged, two-dimensional, U.S. Army Corps of Engineers model CE-QUAL-W2 was used to construct the Hagg Lake model. Calibrated for the years 2000 and 2001 and confirmed with data from 2002 and 2003, modeled parameters included water temperature, ammonia, nitrate, phosphorus, algae, zooplankton, and dissolved oxygen. Several goodness-of-fit statistics were used to quantify model accuracy and bias. Model performance was judged to be excellent for water temperature (annual ME: -0.22 to 0.05 ° C; annual MAE: 0.62 to 0.68 ° C) and dissolved oxygen (annual ME: -0.28 to 0.18 mg/L; annual MAE: 0.43 to 0.92 mg/L), showing that the model is sufficiently accurate for future water resources planning and management.

Delivering good service: personal resources, job satisfaction and nurses' 'customer' (patient) orientation.

PubMed

Gountas, Sandra; Gountas, John; Soutar, Geoffrey; Mavondo, Felix

2014-07-01

To explore the complex relationships between nurses' personal resources, job satisfaction and 'customer' (patient) orientation. Previous research has shown that nursing is highly intensive, emotionally charged work, which affects nurses' job performance and their customer orientation as well as patient or 'customer' satisfaction. This study contributes to the literature by examining how nurses' personal resources relate to their personal satisfaction and customer orientation and the relationships between them. Specifically, this study explores the effects of two facets of emotional labour (deep acting and surface acting), empathic concern, self-efficacy and emotional exhaustion on personal job satisfaction and customer orientation. We also test the moderating effects of inauthenticity and emotional contagion. A quantitative survey. Data were collected through a self-completion questionnaire administered to a sample of 159 Australian nurses, in a public teaching hospital, in 2010. The data were analysed using Partial Least Square analysis. Partial Least Square analysis indicates that the final model is a good fit to the data (Goodness of Fit = 0.51). Deep acting and surface acting have different effects (positive and negative) on job satisfaction and 'customer' orientation, self-efficacy has a positive effect on both and emotional exhaustion has a positive effect on customer orientation and a negative effect on job satisfaction. The moderating effects of emotional contagion and empathic concern, in the final model, are discussed. Understanding the complex interactions between personal resources, job satisfaction and customer orientation helps to increase service providers' (nurses in this study) personal satisfaction and 'customer' orientation particularly in difficult contexts. © 2013 John Wiley & Sons Ltd.

K-S Test for Goodness of Fit and Waiting Times for Fatal Plane Accidents

ERIC Educational Resources Information Center

Gwanyama, Philip Wagala

2005-01-01

The Kolmogorov?Smirnov (K-S) test for goodness of fit was developed by Kolmogorov in 1933 [1] and Smirnov in 1939 [2]. Its procedures are suitable for testing the goodness of fit of a data set for most probability distributions regardless of sample size [3-5]. These procedures, modified for the exponential distribution by Lilliefors [5] and…

Dynamic Bayesian Networks as a Probabilistic Metamodel for Combat Simulations

DTIC Science & Technology

2014-09-18

test is commonly used for large data sets and is the method of comparison presented in Section 5.5. 4.3.3 Kullback - Leibler Divergence Goodness of Fit ...methods exist that might improve the results. A goodness of fit test using the Kullback - Leibler Divergence was proposed in the first paper, but still... Kullback - Leibler Divergence Goodness of Fit Test . . .

Reliability Engineering Handbook

DTIC Science & Technology

1964-06-01

Figure 6-18(a). The Chi-Square (X 2) Test compares the observed values against the Expected Am = 1 A = &. 0002 ) expected values in the tables. 5C 5...9382 .9394 .9406 .9418 .9429 .9441 1.6 .9452 .9463 .9474 .9484 .9495 . 9505 .9515 .9525 .9535 .9545 1.7 .9554 .9564 .9573 .9582 .9591 .9599 .9608

Physical Activity Patterns among U.S. Adults with Disabilities

ERIC Educational Resources Information Center

Chiu, Chung-Yi; An, Ruopeng

2016-01-01

Purpose: To characterize physical activity patterns among people with disabilities using data from a nationally representative health survey. Method: Individual-level data came from the Behavioral Risk Factor Surveillance System 2011 survey. Pearson's chi-squared tests were conducted to assess the difference in the proportion distribution of…

Do College Faculty Embrace Web 2.0 Technology?

ERIC Educational Resources Information Center

Siha, Samia M.; Bell, Reginald Lamar; Roebuck, Deborah

2016-01-01

The authors sought to determine if Rogers's Innovation Decision Process model could analyze Web 2.0 usage within the collegiate environment. The key independent variables studied in relationship to this model were gender, faculty rank, course content delivery method, and age. Chi-square nonparametric tests on the independent variables across…

Validation of the Malay version of the Inventory of Functional Status after Childbirth questionnaire.

PubMed

Noor, Norhayati Mohd; Aziz, Aniza Abd; Mostapa, Mohd Rosmizaki; Awang, Zainudin

2015-01-01

This study was designed to examine the psychometric properties of Malay version of the Inventory of Functional Status after Childbirth (IFSAC). A cross-sectional study. A total of 108 postpartum mothers attending Obstetrics and Gynaecology Clinic, in a tertiary teaching hospital in Malaysia, were involved. Construct validity and internal consistency were performed after the translation, content validity, and face validity process. The data were analyzed using Analysis of Moment Structure version 18 and Statistical Packages for the Social Sciences version 20. The final model consists of four constructs, namely, infant care, personal care, household activities, and social and community activities, with 18 items demonstrating acceptable factor loadings, domain to domain correlation, and best fit (Chi-squared/degree of freedom = 1.678; Tucker-Lewis index = 0.923; comparative fit index = 0.936; and root mean square error of approximation = 0.080). Composite reliability and average variance extracted of the domains ranged from 0.659 to 0.921 and from 0.499 to 0.628, respectively. The study suggested that the four-factor model with 18 items of the Malay version of IFSAC was acceptable to be used to measure functional status after childbirth because it is valid, reliable, and simple.

The Model-Size Effect on Traditional and Modified Tests of Covariance Structures

ERIC Educational Resources Information Center

Herzog, Walter; Boomsma, Anne; Reinecke, Sven

2007-01-01

According to Kenny and McCoach (2003), chi-square tests of structural equation models produce inflated Type I error rates when the degrees of freedom increase. So far, the amount of this bias in large models has not been quantified. In a Monte Carlo study of confirmatory factor models with a range of 48 to 960 degrees of freedom it was found that…

Using Technology-Assisted Instruction and Assessment to Reduce the Effect of Class Size on Student Outcomes in Undergraduate Mathematics Courses

ERIC Educational Resources Information Center

Gleason, Jim

2012-01-01

The implementation of online texts, videos, homework, and tests has changed the process of instruction in introductory college mathematics courses. With this change, more of the students' learning takes place outside of the traditional college classroom and in places such as tutoring centers and dorm rooms. A combination of chi-square tests--for…

Item Performance Across Native Language Groups on the Test of English as a Foreign Language. TOEFL Research Reports, 9.

ERIC Educational Resources Information Center

Alderman, Donald L.; Holland, Paul W.

The Test of English as a Foreign Language (TOEFL) was examined for instances in which the item performance of examinees with comparable scores differed according to their native languages. A chi-square procedure, sensitive to deviations of less than ten percent from the expected frequencies of correct item responses across several language groups,…

Treatment needs and impact of oral health screening of athletes with intellectual disability in Belgium.

PubMed

Fernandez, C; Declerck, D; Dedecker, M; Marks, L

2015-12-30

Special Olympics Special Smiles (SOSS) is an initiative created for oral health data collection and education in oral hygiene for athletes with an intellectual disability. The aims of this study were to evaluate treatment needs of participants of Special Olympics in Belgium 2013 in comparison with those from 2008 and to assess the impact of screening and referral within the SOSS in a group of athletes who participated in two consecutive events, 2012 and 2013. Data were collected following a standardized protocol developed by the U.S. Centres for Disease Control and Prevention, Division of Oral Health. Oral hygiene habits, treatment urgency and reports of oral pain, gingival signs, sealants, untreated caries, missing and filled teeth were recorded. Data analysis of data from 2013 consisted in descriptive statistics followed by the analysis of the data by univariable and multivariable logistic regression. This data was compared with data from 2008 published by Leroy et al., 2012 using Chi square tests. Data from athletes who participated in both Special Olympics events (2012 and 2013) were compared using Exact McNemar's test and Chi-square test for homogeneity of proportions. The level of significance for all tests was set at a p-value < 0.05. A total of 627 athletes with intellectual disability participated to the SOSS program in 2013, while 132 athletes met the inclusion criteria of being a participant at both SO Belgium 2012 and 2013. The prevalence of gingival signs was 44.3 % in 2013, slightly higher than in 2008 (42.4 %). The burden of untreated decay affected 27.1 % of the population showing a net increase in comparison to 2008 (20.9 %). McNemar's test and Chi-square test revealed that there were no statistically significant differences in the proportions of all compared parameters between 2012 and 2013. Special Olympics results from 2013 indicate a considerable unmet treatment need among Belgian Special Olympics Athletes, persistent from 2008 to 2013. Moreover, SO intervention had no impact in the oral health of athletes who participated in 2012 and 2013 events. Continuous efforts for preventive and restorative oral health care are needed for this population.

Nuclear matter parameters and optical model analysis of proton elastic scattering on the doubly magic nucleus 40Ca

NASA Astrophysics Data System (ADS)

Khalaf, A. M.; Khalifa, M. M.; Solieman, A. H. M.; Comsan, M. N. H.

2018-01-01

Owing to its doubly magic nature having equal numbers of protons and neutrons, the 40Ca nuclear scattering can be successfully described by the optical model that assumes a spherical nuclear potential. Therefore, optical model analysis was employed to calculate the elastic scattering cross section for p +40Ca interaction at energies from 9 to 22 MeV as well as the polarization at energies from 10 to 18.2 MeV. New optical model parameters (OMPs) were proposed based on the best fitting to experimental data. It is found that the best fit OMPs depend on the energy by smooth relationships. The results were compared with other OMPs sets regarding their chi square values (χ2). The obtained OMP's set was used to calculate the volume integral of the potentials and the root mean square (rms) value of nuclear matter radius of 40Ca. In addition, 40Ca bulk nuclear matter properties were discussed utilizing both the obtained rms radius and the Thomas-Fermi rms radius calculated using spherical Hartree-Fock formalism employing Skyrme type nucleon-nucleon force. The nuclear scattering SCAT2000 FORTRAN code was used for the optical model analysis.

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.

Factor Structure of the PTSD Checklist for DSM-5: Relationships Among Symptom Clusters, Anger, and Impulsivity.

PubMed

Armour, Cherie; Contractor, Ateka; Shea, Tracie; Elhai, Jon D; Pietrzak, Robert H

2016-02-01

Scarce data are available regarding the dimensional structure of Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) posttraumatic stress disorder (PTSD) symptoms and how factors relate to external constructs. We evaluated six competing models of DSM-5 PTSD symptoms, including Anhedonia, Externalizing Behaviors, and Hybrid models, using confirmatory factor analyses in a sample of 412 trauma-exposed college students. We then examined whether PTSD symptom clusters were differentially related to measures of anger and impulsivity using Wald chi-square tests. The seven-factor Hybrid model was deemed optimal compared with the alternatives. All symptom clusters were associated with anger; the strongest association was between externalizing behaviors and anger (r = 0.54). All symptom clusters, except re-experiencing and avoidance, were associated with impulsivity, with the strongest association between externalizing behaviors and impulsivity (r = 0.49). A seven-factor Hybrid model provides superior fit to DSM-5 PTSD symptom data, with the externalizing behaviors factor being most strongly related to anger and impulsivity.

Conservativeness in Rejection of the Null Hypothesis when Using the Continuity Correction in the MH Chi-Square Test in DIF Applications

ERIC Educational Resources Information Center

Paek, Insu

2010-01-01

Conservative bias in rejection of a null hypothesis from using the continuity correction in the Mantel-Haenszel (MH) procedure was examined through simulation in a differential item functioning (DIF) investigation context in which statistical testing uses a prespecified level [alpha] for the decision on an item with respect to DIF. The standard MH…

Noncentral Chi-Square versus Normal Distributions in Describing the Likelihood Ratio Statistic: The Univariate Case and Its Multivariate Implication

ERIC Educational Resources Information Center

Yuan, Ke-Hai

2008-01-01

In the literature of mean and covariance structure analysis, noncentral chi-square distribution is commonly used to describe the behavior of the likelihood ratio (LR) statistic under alternative hypothesis. Due to the inaccessibility of the rather technical literature for the distribution of the LR statistic, it is widely believed that the…

Exploring relationships among social integration, social isolation, self-rated health, and demographics among Latino day laborers.

PubMed

Steel, Kenneth C; Fernandez-Esquer, Maria Eugenia; Atkinson, John S; Taylor, Wendell C

2018-05-01

Research indicates social integration and social isolation are related to health, and Latino day laborers (LDLs) tend to be socially isolated and, thus, at high risk for adverse health consequences. relationships among social isolation, social integration, self-rated health (SRH), and demographics were examined in a sample of LDLs to contribute to the literature on social networks and health in this and other migrant populations. We analyzed data from 324 LDLs who participated in Proyecto SHILOS (Salud del Hombre Inmigrante Latino), a Houston-based survey of Latino immigrant men's health. Based on the literature, we hypothesized SRH would be (1) positively associated with social integration and (2) negatively associated with social isolation. All proposed measures were first entered into a correlation matrix to identify significant bivariate relationships (p ≤ .05, two-tailed). Associations between variables that were directly correlated with SRH and variables that were, in turn, proximally associated with these variables were then used to develop a structural equation path model of SRH. Individual paths in the model were measured for significance, and goodness of fit was assessed by the model chi-square, the Comparative Fit Index, and the Root Mean Square Error of Approximation. Inconsistent with the first hypothesis, SRH was negatively associated with social integration, as measured by the number of trusted friends. Consistent with the second hypothesis, SRH was negatively associated with social isolation, as measured by needing someone to talk to. More frequent contact with family was also negatively associated with social isolation. Our findings suggest social integration may not always protect and promote health. Therefore, assessing the quality of LDLs' different relationships, not just the quantity, is vital. Future studies should further analyze the effects that social resources have on perceptions of social isolation and health in LDLs and other migrant populations.

Association between litterers' profile and littering behavior: A chi-square approach

NASA Astrophysics Data System (ADS)

Asmui, Mas'udah; Zaki, Suhanom Mohd; Wahid, Sharifah Norhuda Syed; Mokhtar, Noorsuraya Mohd; Harith, Siti Suhaila

2017-05-01

Littering is not a novelty, yet a prolonged issue. The solutions have been discussed for a long time; however this issue still remains unresolved. Littering is commonly associated with littering behavior and awareness. The littering behavior is normally influenced by the litter profile such as gender, family income, education level and age. Jengka Street market, which is located in Pahang, is popularly known as a trade market. It offers diversities of wet and dry goods and is awaited by local residents and tourists. This study analyzes association between litterers' profile and littering behavior. Littering behavior is measured based on factors of trash bin facilities, awareness campaign and public littering behavior. 114 respondents were involved in this study with 62 (54.39%) are female aged more than 18 years old and majority of these female respondents are diploma holders. In addition, 78.95% of the respondents have family income below than RM3,000.00 per month. Based on the data analysis, it was found that first-time visitors littered higher than frequent visitors, lack of providing trash bin facilities contributes to positive littering behavior and there is a significant association between litterers' age and littering behavior by using chi-square approach.

VizieR Online Data Catalog: WASP-22, WASP-41, WASP-42, WASP-55 (Southworth+, 2016)

NASA Astrophysics Data System (ADS)

Southworth, J.; Tregloan-Reed, J.; Andersen, M. I.; Calchi Novati, S.; Ciceri, S.; Colque, J. P.; D'Ago, G.; Dominik, M.; Evans, D. F.; Gu, S.-H.; Herrera-Cordova, A.; Hinse, T. C.; Jorgensen, U. G.; Juncher, D.; Kuffmeier, M.; Mancini, L.; Peixinho, N.; Popovas, A.; Rabus, M.; Skottfelt, J.; Tronsgaard, R.; Unda-Sanzana, E.; Wang, X.-B.; Wertz, O.; Alsubai, K. A.; Andersen, J. M.; Bozza, V.; Bramich, D. M.; Burgdorf, M.; Damerdji, Y.; Diehl, C.; Elyiv, A.; Figuera Jaimes, R.; Haugbolle, T.; Hundertmark, M.; Kains, N.; Kerins, E.; Korhonen, H.; Liebig, C.; Mathiasen, M.; Penny, M. T.; Rahvar, S.; Scarpetta, G.; Schmidt, R. W.; Snodgrass, C.; Starkey, D.; Surdej, J.; Vilela, C.; von Essen, C.; Wang, Y.

2018-05-01

17 light curves of transits of the extrasolar planetary systems WASP-22, WASP-41, WASP-42 and WASP-55 are presented. 13 of the light curves were obtained using the Danish 1.54m telescope at ESO La Silla, Chile, in the Bessell R or Bessell I passbands. The other 4 light curves were obtained using the 84cm telescope at Observatorio Cerro Armazones, Chile, using either an R filter or no filter. The errorbars for each transit have been scaled so the best-fitting model (obtained using the JKTEBOP code) has a reduced chi-squared value of 1.0. (4 data files).

2D Bayesian automated tilted-ring fitting of disc galaxies in large H I galaxy surveys: 2DBAT

NASA Astrophysics Data System (ADS)

Oh, Se-Heon; Staveley-Smith, Lister; Spekkens, Kristine; Kamphuis, Peter; Koribalski, Bärbel S.

2018-01-01

We present a novel algorithm based on a Bayesian method for 2D tilted-ring analysis of disc galaxy velocity fields. Compared to the conventional algorithms based on a chi-squared minimization procedure, this new Bayesian-based algorithm suffers less from local minima of the model parameters even with highly multimodal posterior distributions. Moreover, the Bayesian analysis, implemented via Markov Chain Monte Carlo sampling, only requires broad ranges of posterior distributions of the parameters, which makes the fitting procedure fully automated. This feature will be essential when performing kinematic analysis on the large number of resolved galaxies expected to be detected in neutral hydrogen (H I) surveys with the Square Kilometre Array and its pathfinders. The so-called 2D Bayesian Automated Tilted-ring fitter (2DBAT) implements Bayesian fits of 2D tilted-ring models in order to derive rotation curves of galaxies. We explore 2DBAT performance on (a) artificial H I data cubes built based on representative rotation curves of intermediate-mass and massive spiral galaxies, and (b) Australia Telescope Compact Array H I data from the Local Volume H I Survey. We find that 2DBAT works best for well-resolved galaxies with intermediate inclinations (20° < i < 70°), complementing 3D techniques better suited to modelling inclined galaxies.

Assessing the performance and reliability of PERSIANN-CDR satellite-based rainfall estimates over Spain: case study of rainfall Dry Spell Lengths (DSL)

NASA Astrophysics Data System (ADS)

Garcia Galiano, S. G.; Giraldo Osorio, J. D.; Nguyen, P.; Hsu, K. L.; Braithwaite, D.; Olmos, P.; Sorooshian, S.

2015-12-01

Studying Spain's long-term variability and changing trends in rainfall, due to its unique position in the Mediterranean basin (i.e., the latitudinal gradient from North to South and its orographic variation), can provide a valuable insight into how hydroclimatology of the region has changed. A recently released high resolution satellite-based global daily precipitation climate dataset PERSIANN-CDR (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Network - Climate Data Record), provided the opportunity to conduct such study. It covers the period 01/01/1983 - to date, at 0.25° resolution. In areas without a dense network of rain-gauges, the PERSIANN-CDR dataset could be useful for identifying the reliability of regional climate models (RCMs), in order to build robust RCMs ensemble for reducing the uncertainties in the climate and hydrological projections. However, before using this data set for RCM evaluation, an assessment of performance of PERSIANN-CDR dataset against in-situ observations is necessary. The high-resolution gridded daily rain-gauge dataset, named Spain02, was employed in this study. The variable Dry Spell Lengths (DSL) considering 1 mm and 10 mm as thresholds of daily rainfall, and the time period 1988-2007 was defined for the study. A procedure for improving the consistency and homogeneity between the two datasets was applied. The assessment is based on distributional similarity and the well-known statistical tests (Smirnov-Kolmogorov of two samples and Chi-Square) are used as fitting criteria. The results demonstrate good fit of PERSIANN-CDR over whole Spain, for threshold 10 mm/day. However, for threshold 1 mm/day PERSIANN-CDR compares well with Spain02 dataset for areas with high values of rainfall (North of Spain); while in semiarid areas (South East of Spain) there is strong overestimation of short DSLs. Overall, PERSIANN-CDR demonstrate its robustness in the simulation of DSLs for the highest thresholds.

Evaluating cultural competence among Japanese clinical nurses: Analyses of a translated scale.

PubMed

Noji, Ariko; Mochizuki, Yuki; Nosaki, Akiko; Glaser, Dale; Gonzales, Lucia; Mizobe, Akiko; Kanda, Katsuya

2017-06-01

This paper describes the factor analysis testing and construct validation of the Japanese version of the Caffrey Cultural Competence Health Services (J-CCCHS). The inventory, composed of 28 items, was translated using language and subject matter experts. Psychometric testing (exploratory factor, alpha reliability, and confirmatory factor analyses) was undertaken with nurses (N = 7494, 92% female, mean age 32.6 years) from 19 hospitals across Japan. Principal components extraction with varimax rotation yielded a 5-factor solution (62.31% variance explained) that was labeled: knowledge, comfort-proximal, comfort-distal, awareness, and awareness of national policy. Cronbach α for the subscales ranged from 0.756 to 0.892. In confirmatory factor analysis using the robust maximum likelihood estimator, the chi-square test was as follows: χ 2 (340) = 14604.44, P < .001. After correlated errors were introduced, there was evidence of improved model fit (χ 2 (335) = 8681.61, P < .05) but the other indices showed improvement (RMSEA = .058 [90% CI, 0.057-0.059], TLI = .891, CFI = .903, and SRMR = .059). The discriminating power of the J-CCCHS was indicated by statistically mean differences in J-CCCHS subscale scores between predefined groups. Taking into consideration that this is the first foray into construct validation for this instrument, and that fit was improved when a subsequent data driven model was tested, and it has the ability to distinguish between known groups that are expected to differ in cultural competence, the instrument can be of value to clinicians and educators alike. © 2017 John Wiley & Sons Australia, Ltd.

Study on creep behavior of Grade 91 heat-resistant steel using theta projection method

NASA Astrophysics Data System (ADS)

Ren, Facai; Tang, Xiaoying

2017-10-01

Creep behavior of Grade 91 heat-resistant steel used for steam cooler was characterized using the theta projection method. Creep tests were conducted at the temperature of 923K under the stress ranging from 100-150MPa. Based on the creep curve results, four theta parameters were established using a nonlinear least square fitting method. Four theta parameters showed a good linearity as a function of stress. The predicted curves coincided well with the experimental data and creep curves were also modeled to the low stress level of 60MPa.

Women at Sea: Welcome Aboard.

DTIC Science & Technology

1983-03-01

should be familiar with typical military/navy terms, and elementary statistical tests (T-test, Chi Square, and One-Way Analysis of Variance). The ...and the media. One theory is that the gradual internalization or acceptance of values and ideals (which is influenced by the individual’s class, family...completed with a comparison of the two. A similar format is followed for the commanding officer’s data. Three sets of statistical tests were done on the

Comparison of random regression models with Legendre polynomials and linear splines for production traits and somatic cell score of Canadian Holstein cows.

PubMed

Bohmanova, J; Miglior, F; Jamrozik, J; Misztal, I; Sullivan, P G

2008-09-01

A random regression model with both random and fixed regressions fitted by Legendre polynomials of order 4 was compared with 3 alternative models fitting linear splines with 4, 5, or 6 knots. The effects common for all models were a herd-test-date effect, fixed regressions on days in milk (DIM) nested within region-age-season of calving class, and random regressions for additive genetic and permanent environmental effects. Data were test-day milk, fat and protein yields, and SCS recorded from 5 to 365 DIM during the first 3 lactations of Canadian Holstein cows. A random sample of 50 herds consisting of 96,756 test-day records was generated to estimate variance components within a Bayesian framework via Gibbs sampling. Two sets of genetic evaluations were subsequently carried out to investigate performance of the 4 models. Models were compared by graphical inspection of variance functions, goodness of fit, error of prediction of breeding values, and stability of estimated breeding values. Models with splines gave lower estimates of variances at extremes of lactations than the model with Legendre polynomials. Differences among models in goodness of fit measured by percentages of squared bias, correlations between predicted and observed records, and residual variances were small. The deviance information criterion favored the spline model with 6 knots. Smaller error of prediction and higher stability of estimated breeding values were achieved by using spline models with 5 and 6 knots compared with the model with Legendre polynomials. In general, the spline model with 6 knots had the best overall performance based upon the considered model comparison criteria.

Willingness to support antenatal blood donation among married men in a Metropolitan City in North-central Nigeria.

PubMed

Ameen, H A; Isiaka-Lawal, S; Okesina, B S; Shittu, R O; Sanni, M A; Uthman, M M B; Bolarinwa, O A

2015-01-01

Improving blood availability through voluntary or compulsory antenatal blood donation is pivotal to reducing maternal morbidity and mortality in developing countries. Willingness to donate blood is adjudged to be an important step to the actual practice of donating blood. This study aimed to determine the knowledge, attitude and willingness of men towards antenatal blood donation. This was a descriptive cross-sectional study. A multi-stage sampling technique was used to recruit 500 married men into the study using interviewer-administered questionnaire. Data analysis was done using SPSS version 16 software package. Pearson's Chi-squared test was used to test for significant associations between variables. A P < 0.05 was considered as statistically significant. More than half 300 (60%) of the respondents had good knowledge of antenatal blood donation in general. Majority (85.8%) of the respondents were willing to support voluntary blood donation. The overall attitude to blood donation was positive in 77.8% of the respondents. A significantly higher proportion 268 (89.3%) of respondents with good knowledge of antenatal blood donation were willing to donate blood (P = 0.0006). The majority have good knowledge and positive attitude towards antenatal blood donation. However, there is need to urgently transform this positive attitude to action through continual public enlightenment to reduce maternal morbidity and mortality.

Chinese version of Impact of Weight on Quality of Life for Kids: psychometric properties in a large school-based sample.

PubMed

He, Jinbo; Zhu, Hong; Luo, Xingwei; Cai, Taisheng; Wu, Siyao; Lu, Yao

2016-06-01

The Impact of Weight on Quality of Life for Kids (IWQOL-Kids) is the first self-report questionnaire for assessing weight-related quality of life for youth. However, there is no Chinese version of IWQOL-Kids. Thus, the objective of this research was to translate IWQOL-Kids into Mandarin and evaluate its psychometric properties in a large school-based sample. The total sample included 2282 participants aged 11-18 years old, including 1703 non-overweight, 386 overweight and 193 obese students. IWQOL-Kids was translated and culturally adapted by following the international guidelines for instrument linguistic validation procedures. The psychometric evaluation included internal consistency, test-retest reliability, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), convergent validity and discriminant validity. Cronbach's α for the Chinese version of IWQOL-Kids (IWQOL-Kids-C) was 0.956 and ranged from 0.891 to 0.927 for subscales. IWQOL-Kids-C showed a test-retest coefficient of 0.937 after 2 weeks and ranged from 0.847 to 0.903 for subscales. The original four-factor model was reproduced by EFA after seven iterations, accounting for 69.28% of the total variance. CFA demonstrated that the four-factor model had good fit indices with comparative fit index = 0.92, normed fit index = 0.91, goodness of fit index = 0.86, root mean square error of approximation = 0.07 and root mean square residual = 0.03. Convergent validity and discriminant validity were demonstrated with higher correlations between similar constructs and lower correlations between dissimilar constructs of IWQOL-Kids-C and PedsQL™ 4.0. The significant differences were found across the body mass index groups, and IWQOL-Kids-C had higher effect sizes than PedsQL™4.0 when comparing non-overweight and obese groups, supporting the sensitivity of IWQOL-Kids-C. IWQOL-Kids-C is a satisfactory, valid and reliable instrument to assess weight-related quality of life for Chinese children and adolescents aged 11-18 years old. © The Author 2015. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Evaluation of the VIDAS Listeria (LIS) immunoassay for the detection of Listeria in foods using demi-Fraser and Fraser enrichment broths, as modification of AOAC Official Method 999.06 (AOAC Official Method 2004.06).

PubMed

Silbernagel, Karen M; Jechorek, Robert P; Kaufer, Amanda L; Johnson, Ronald L; Aleo, V; Brown, B; Buen, M; Buresh, J; Carson, M; Franklin, J; Ham, P; Humes, L; Husby, G; Hutchins, J; Jechorek, R; Jenkins, J; Kaufer, A; Kexel, N; Kora, L; Lam, L; Lau, D; Leighton, S; Loftis, M; Luc, S; Martin, J; Nacar, I; Nogle, J; Park, J; Schultz, A; Seymore, D; Smith, C; Smith, J; Thou, P; Ulmer, M; Voss, R; Weaver, V

2005-01-01

A multilaboratory study was conducted to compare the VIDAS LIS immunoassay with the standard cultural methods for the detection of Listeria in foods using an enrichment modification of AOAC Official Method 999.06. The modified enrichment protocol was implemented to harmonize the VIDAS LIS assay with the VIDAS LMO2 assay. Five food types--brie cheese, vanilla ice cream, frozen green beans, frozen raw tilapia fish, and cooked roast beef--at 3 inoculation levels, were analyzed by each method. A total of 15 laboratories representing government and industry participated. In this study, 1206 test portions were tested, of which 1170 were used in the statistical analysis. There were 433 positive by the VIDAS LIS assay and 396 positive by the standard culture methods. A Chi-square analysis of each of the 5 food types, at the 3 inoculation levels tested, was performed. The resulting average Chi square analysis, 0.42, indicated that, overall, there are no statistical differences between the VIDAS LIS assay and the standard methods at the 5% level of significance.

Effects of T'ai Chi on Serotonin, Nicotine Dependency, Depression, and Anger in Hospitalized Alcohol-Dependent Patients.

PubMed

Oh, Chung-Uk; Kim, Nam-Cho

2016-12-01

The aim of this study was to investigate the effects of t'ai chi on blood serotonin levels, nicotine dependence, depression, and anger in hospitalized alcohol-dependent patients. This study followed an experimental and nonequivalent control group in a non-synchronized design. It was performed in a hospital located in Young Ju city, Korea, from April to August 2013. Thirty-eight patients who were hospitalized with alcohol dependence were included. They were randomly divided into an experimental and a control group, with 19 patients in each group. Patients in the experimental group practiced the 24-posture yang style t'ai chi for 50 min three times per week for 8 weeks as part of the routine hospital rehabilitation program, and those in the control group followed only the routine hospital rehabilitation program. The effect of treatment was measured using blood serotonin levels and a questionnaire on nicotine dependence, depression, and anger. Both measurements were performed before and after 8 weeks of intervention. Data were analyzed using the t-test, chi-square test, and paired t-tests. The experimental group showed a significantly increased blood serotonin level (p = 0.001) and significantly reduced nicotine dependence, depression, and anger (p = 0.001) than the control group did after 8 weeks of treatment. T'ai chi was shown to be an effective nursing intervention in hospitalized alcohol-dependent patients.

Injury Rate and Patterns Among CrossFit Athletes

PubMed Central

Weisenthal, Benjamin M.; Beck, Christopher A.; Maloney, Michael D.; DeHaven, Kenneth E.; Giordano, Brian D.

2014-01-01

Background: CrossFit is a type of competitive exercise program that has gained widespread recognition. To date, there have been no studies that have formally examined injury rates among CrossFit participants or factors that may contribute to injury rates. Purpose: To establish an injury rate among CrossFit participants and to identify trends and associations between injury rates and demographic categories, gym characteristics, and athletic abilities among CrossFit participants. Study Design: Descriptive epidemiology study. Methods: A survey was conducted, based on validated epidemiologic injury surveillance methods, to identify patterns of injury among CrossFit participants. It was sent to CrossFit gyms in Rochester, New York; New York City, New York; and Philadelphia, Pennsylvania, and made available via a posting on the main CrossFit website. Participants were encouraged to distribute it further, and as such, there were responses from a wide geographical location. Inclusion criteria included participating in CrossFit training at a CrossFit gym in the United States. Data were collected from October 2012 to February 2013. Data analysis was performed using Fisher exact tests and chi-square tests. Results: A total of 486 CrossFit participants completed the survey, and 386 met the inclusion criteria. The overall injury rate was determined to be 19.4% (75/386). Males (53/231) were injured more frequently than females (21/150; P = .03). Across all exercises, injury rates were significantly different (P < .001), with shoulder (21/84), low back (12/84), and knee (11/84) being the most commonly injured overall. The shoulder was most commonly injured in gymnastic movements, and the low back was most commonly injured in power lifting movements. Most participants did not report prior injury (72/89; P < .001) or discomfort in the area (58/88; P < .001). Last, the injury rate was significantly decreased with trainer involvement (P = .028). Conclusion: The injury rate in CrossFit was approximately 20%. Males were more likely to sustain an injury than females. The involvement of trainers in coaching participants on their form and guiding them through the workout correlates with a decreased injury rate. The shoulder and lower back were the most commonly injured in gymnastic and power lifting movements, respectively. Participants reported primarily acute and fairly mild injuries. PMID:26535325

Smile line and occlusion: An epidemiological study

PubMed Central

Harati, Mahsa; Mostofi, Shahbaz Naser; Jalalian, Ezzatollah; Rezvani, Gholamreza

2013-01-01

Background: The purpose of the present study was to discuss some new concepts of the desirable characteristics of smile tooth display. Due to the increasing application of cosmetic dental treatments, there is an increasing need for better understanding of the esthetic principles. Materials and Methods: In the present descriptive study, with 212 participants, included were patients with no history of orthodontic treatment, loss or prosthetic replacement of anterior teeth, extracted teeth, lips with asymmetry or a history of trauma. Chi-square test was used to determine possible significances in the relation of smile line to Angle occlusion class, overbite and overjet and arch form. A P level of <0.05 was set as to be significant. Results: Chi-square test indicated that there was a significant difference between the smile design and overbite, overjet and gender but no statistically significant association was found between the smile design and crossbite, molar Angle classification and arch form. Conclusion: Within the limitations of such studies, it might be concluded that there is a significant and important relation between some occlusal parameters and smile design, which must be considered. PMID:24379858

Smile line and occlusion: An epidemiological study.

PubMed

Harati, Mahsa; Mostofi, Shahbaz Naser; Jalalian, Ezzatollah; Rezvani, Gholamreza

2013-11-01

The purpose of the present study was to discuss some new concepts of the desirable characteristics of smile tooth display. Due to the increasing application of cosmetic dental treatments, there is an increasing need for better understanding of the esthetic principles. In the present descriptive study, with 212 participants, included were patients with no history of orthodontic treatment, loss or prosthetic replacement of anterior teeth, extracted teeth, lips with asymmetry or a history of trauma. Chi-square test was used to determine possible significances in the relation of smile line to Angle occlusion class, overbite and overjet and arch form. A P level of <0.05 was set as to be significant. Chi-square test indicated that there was a significant difference between the smile design and overbite, overjet and gender but no statistically significant association was found between the smile design and crossbite, molar Angle classification and arch form. Within the limitations of such studies, it might be concluded that there is a significant and important relation between some occlusal parameters and smile design, which must be considered.

Doing More with Less: A Preliminary Study of the School District Investment.

ERIC Educational Resources Information Center

MacPhail-Wilcox, Bettye

1983-01-01

Changes in cash management practices from 1978 to 1981 were investigated in a random sample of 145 North Carolina school districts, stratified by attendance size. Analysis using chi-square tests indicated the level of investment sophistication (as measured by the proportion of cash invested) has increased, especially for large districts. (RW)

Racial/ethnic variation in mental health correlates of substance use among college students.

PubMed

Sumstine, Stephanie; Cruz, Sheena; Schroeder, Cassandra; Takeda, Summer; Bavarian, Niloofar

2018-01-01

This study investigated mental health indicators, substance use, and their relationships, by race/ethnicity. A probability sample of 1,053 students at two California universities self-reported their frequency of substance use and rated their experience with indicators of mental health. One-way analysis of variance (ANOVA), chi-square tests, and multivariate censored regression models were estimated to examine which indicators of mental health were associated with each substance use form by race/ethnicity. Results from the one-way ANOVA and chi-square tests showed differences in substance use prevalence and mental health by race/ethnicity. For example, students who identified as White demonstrate a higher prevalence for every form of substance use in comparison to the Asian, Latino, and "All other" categories. Results from the regression showed, among Whites, inattention was associated with prescription stimulant misuse, and psychological distress was associated with marijuana use. Among Latinos, inattention was associated with cocaine and prescription stimulant use. Among Asians, psychological distress was associated with tobacco use and the misuse of prescription painkillers. Findings highlight the need to ensure subpopulations receive needed services.

Clinical Skills Passport: A Method to Increase Participation in Clinical Skills by Medical Students During a Surgery Clerkship.

PubMed

Read, Thomas E

To prospectively evaluate the effect of introducing a clinical skills "passport" on medical students' reporting of their experience with basic clinical skills. A prospective longitudinal intervention study was conducted. Medical students were administered a questionnaire at the conclusion of their 12-week surgery clerkship regarding their experience with 15 clinical skills, inquiring whether they had "learned on surgery clerkship", "learned before surgery clerkship", or "not learned". Preintervention baseline data were obtained for 2 consecutive academic years (n = 213 students). In the third year, students (n = 124) were given a clinical skills passport to document performance of 8 of the 15 skills under the supervision of a surgical resident or faculty member. After excluding from analysis those students who learned a skill before their surgery clerkship, the fraction of students who reported learning clinical skills during their surgery clerkship before and after the introduction of the clinical skills passport was compared using Fisher exact test and chi-squared test, where appropriate (p ≤ 0.003 was considered significant; Bonferroni correction for multiple comparisons). Washington University School of Medicine. A total of 337 medical students completing the junior surgery clerkship over a 3-year period were included in the study. All 337 students completed a survey. Considering each skill individually, survey response rate was 5045/5055 (99.8%). Combining all responses for all skills, the fraction of students reporting that skills were learned on the surgery clerkship increased after the introduction of the clinical skills passport (1498/1938 [77%] preintervention vs. 974/1109 [88%] postintervention, p < 0.0001, chi square). After the introduction of the clinical skills passport, the fraction of students reporting that a skill was "learned on surgery clerkship" significantly increased for the 8 skills listed on the passport (1026/1699 [83%] preintervention vs. 685/714 [96%] postintervention, p < 0.0001, chi square), but did not increase for the 7 skills not listed on the passport (472/695 [68%] preintervention vs. 289/395 [73%] postintervention, p = 0.08, chi square). Considering each skill individually, after the introduction of the clinical skills passport, the fraction of students reporting that a skill was "learned on surgery clerkship" significantly increased for 4/15 skills (all listed on the clinical passport) and decreased for 0/15 skills (p < 0.003, Fisher exact test, 2 tailed). Institution of a clinical skills passport system during a surgery clerkship increased medical student reporting of their performance of basic clinical skills. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.