A Snapshot of Young Children's Mathematical Competencies: Results from the Longitudinal Study of Australian Children

ERIC Educational Resources Information Center

MacDonald, Amy; Carmichael, Colin

2015-01-01

This article presents a snapshot of the mathematical competencies of children aged four to five years in Australian early childhood education settings, as perceived by their educators. Data are presented from a nationally-representative sample of 6511 children participating in the Longitudinal Study of Australian Children (LSAC). The results…

Colorism and Educational Outcomes of Asian Americans: Evidence from the National Longitudinal Study of Adolescent Health

ERIC Educational Resources Information Center

Ryabov, Igor

2016-01-01

Using a nationally representative longitudinal data set, the current study examines the link between colorism and educational attainment of Asian American young adults. Three levels of educational attainment are used as outcomes: high school diploma, some college and a Bachelor's degree or higher. Independent variables include skin tone, ethnic…

Analyzing longitudinal data with the linear mixed models procedure in SPSS.

PubMed

West, Brady T

2009-09-01

Many applied researchers analyzing longitudinal data share a common misconception: that specialized statistical software is necessary to fit hierarchical linear models (also known as linear mixed models [LMMs], or multilevel models) to longitudinal data sets. Although several specialized statistical software programs of high quality are available that allow researchers to fit these models to longitudinal data sets (e.g., HLM), rapid advances in general purpose statistical software packages have recently enabled analysts to fit these same models when using preferred packages that also enable other more common analyses. One of these general purpose statistical packages is SPSS, which includes a very flexible and powerful procedure for fitting LMMs to longitudinal data sets with continuous outcomes. This article aims to present readers with a practical discussion of how to analyze longitudinal data using the LMMs procedure in the SPSS statistical software package.

Gene expression models for prediction of longitudinal dispersion coefficient in streams

NASA Astrophysics Data System (ADS)

Sattar, Ahmed M. A.; Gharabaghi, Bahram

2015-05-01

Longitudinal dispersion is the key hydrologic process that governs transport of pollutants in natural streams. It is critical for spill action centers to be able to predict the pollutant travel time and break-through curves accurately following accidental spills in urban streams. This study presents a novel gene expression model for longitudinal dispersion developed using 150 published data sets of geometric and hydraulic parameters in natural streams in the United States, Canada, Europe, and New Zealand. The training and testing of the model were accomplished using randomly-selected 67% (100 data sets) and 33% (50 data sets) of the data sets, respectively. Gene expression programming (GEP) is used to develop empirical relations between the longitudinal dispersion coefficient and various control variables, including the Froude number which reflects the effect of reach slope, aspect ratio, and the bed material roughness on the dispersion coefficient. Two GEP models have been developed, and the prediction uncertainties of the developed GEP models are quantified and compared with those of existing models, showing improved prediction accuracy in favor of GEP models. Finally, a parametric analysis is performed for further verification of the developed GEP models. The main reason for the higher accuracy of the GEP models compared to the existing regression models is that exponents of the key variables (aspect ratio and bed material roughness) are not constants but a function of the Froude number. The proposed relations are both simple and accurate and can be effectively used to predict the longitudinal dispersion coefficients in natural streams.

Imputation of Test Scores in the National Education Longitudinal Study of 1988 (NELS:88). Working Paper Series.

ERIC Educational Resources Information Center

Bokossa, Maxime C.; Huang, Gary G.

This report describes the imputation procedures used to deal with missing data in the National Education Longitudinal Study of 1988 (NELS:88), the only current National Center for Education Statistics (NCES) dataset that contains scores from cognitive tests given the same set of students at multiple time points. As is inevitable, cognitive test…

A Comparison of Single-Sex and Coeducational Catholic Secondary Schooling: Evidence from the National Educational Longitudinal Study of 1988.

ERIC Educational Resources Information Center

LePore, Paul C.; Warren, John Robert

1997-01-01

Results from a comparison of single-sex and coeducational Catholic secondary schools using data from the National Educational Longitudinal Study of 1988 suggest that single-sex Catholic high schools are not especially favorable academic settings, and that any advantages of the schools only benefited boys. Pre-enrollment differences may explain…

Goals Set in the Land of the Living/Dying: A Longitudinal Study of Patients Living with Advanced Cancer

ERIC Educational Resources Information Center

Nissim, Rinat; Rennie, David; Fleming, Stephen; Hales, Sarah; Gagliese, Lucia; Rodin, Gary

2012-01-01

A longitudinal qualitative research study was undertaken to provide an understanding of a prolonged experience of advanced cancer, as seen through the eyes of dying individuals. Using a variant of the grounded theory method, the authors theoretically sampled, from outpatient clinics in a large comprehensive cancer treatment center, 27 patients…

National Longitudinal Study of the High School Class of 1972: Critical Data Base. 22U-884.

ERIC Educational Resources Information Center

Talbert, Robin

The National Longitudinal Study of the High School Class of 1972 (NLS) critical data base contains 151 items (plus background information) from the base year and followup questionnaires; about thirty-seven percent of all items. This set of critical items consists of: (1) basic demographic variables; (2) items necessary for defining activity states…

The Relationship between Early Language, Cognitive and Social Development through a Longitudinal Study of Autistic Children.

ERIC Educational Resources Information Center

Ogura, Tamiko

The development of and relationship between early language, symbolic play, sensorimotor skills, and social development were examined in a longitudinal study conducted in Japan with two young autistic males who were observed from the approximate ages of 2 to 4 years in clinic, day care, and home settings. One child acquired speech; the other did…

A Longitudinal Study of the Effects of OPAC Screen Changes on Searching Behavior and Searcher Success.

ERIC Educational Resources Information Center

Blecic, Deborah D.; Dorsch, Josephine L.; Koenig, Melissa H.; Bangalore, Nimala S.

1999-01-01

Describes a longitudinal study of four sets of OPAC (online public access catalog) transaction logs that examined the effects of screen changes in helping searchers improve their search behavior. Results show that while screen changes initially had a positive impact on search behavior, they were not always sustained over time. (Author/LRW)

Using National Education Longitudinal Data Sets in School Counseling Research

ERIC Educational Resources Information Center

Bryan, Julia A.; Day-Vines, Norma L.; Holcomb-McCoy, Cheryl; Moore-Thomas, Cheryl

2010-01-01

National longitudinal databases hold much promise for school counseling researchers. Several of the more frequently used data sets, possible professional implications, and strategies for acquiring training in the use of large-scale national data sets are described. A 6-step process for conducting research with the data sets is explicated:…

Mixed models approaches for joint modeling of different types of responses.

PubMed

Ivanova, Anna; Molenberghs, Geert; Verbeke, Geert

2016-01-01

In many biomedical studies, one jointly collects longitudinal continuous, binary, and survival outcomes, possibly with some observations missing. Random-effects models, sometimes called shared-parameter models or frailty models, received a lot of attention. In such models, the corresponding variance components can be employed to capture the association between the various sequences. In some cases, random effects are considered common to various sequences, perhaps up to a scaling factor; in others, there are different but correlated random effects. Even though a variety of data types has been considered in the literature, less attention has been devoted to ordinal data. For univariate longitudinal or hierarchical data, the proportional odds mixed model (POMM) is an instance of the generalized linear mixed model (GLMM; Breslow and Clayton, 1993). Ordinal data are conveniently replaced by a parsimonious set of dummies, which in the longitudinal setting leads to a repeated set of dummies. When ordinal longitudinal data are part of a joint model, the complexity increases further. This is the setting considered in this paper. We formulate a random-effects based model that, in addition, allows for overdispersion. Using two case studies, it is shown that the combination of random effects to capture association with further correction for overdispersion can improve the model's fit considerably and that the resulting models allow to answer research questions that could not be addressed otherwise. Parameters can be estimated in a fairly straightforward way, using the SAS procedure NLMIXED.

A Fast EM Algorithm for Fitting Joint Models of a Binary Response and Multiple Longitudinal Covariates Subject to Detection Limits

PubMed Central

Bernhardt, Paul W.; Zhang, Daowen; Wang, Huixia Judy

2014-01-01

Joint modeling techniques have become a popular strategy for studying the association between a response and one or more longitudinal covariates. Motivated by the GenIMS study, where it is of interest to model the event of survival using censored longitudinal biomarkers, a joint model is proposed for describing the relationship between a binary outcome and multiple longitudinal covariates subject to detection limits. A fast, approximate EM algorithm is developed that reduces the dimension of integration in the E-step of the algorithm to one, regardless of the number of random effects in the joint model. Numerical studies demonstrate that the proposed approximate EM algorithm leads to satisfactory parameter and variance estimates in situations with and without censoring on the longitudinal covariates. The approximate EM algorithm is applied to analyze the GenIMS data set. PMID:25598564

Longitudinal Surveys of Australian Youth (LSAY) 2009 Cohort: Wave 2 (2010)-- Questionnaire. Technical Report 71A

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This technical paper contains the questionnaire for the LSAY 2009 cohort Wave 2 (2010) data set.

Longitudinal Surveys of Australian Youth (LSAY) 2009 Cohort: Wave 3 (2011)--Questionnaire. Technical Report 72A

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This technical paper contains the questionnaire for the LSAY 2009 cohort Wave 3 (2011) data set.

Longitudinal Cross-Gender Factorial Invariance of the Academic Motivation Scale

ERIC Educational Resources Information Center

Grouzet, Frederick M. E.; Otis, Nancy; Pelletier, Luc G.

2006-01-01

This study examined the measurement and latent construct invariance of the Academic Motivation Scale (Vallerand, Blais, Brier, & Pelletier, 1989; Vallerand et al., 1992, 1993) across both gender and time. An integrative analytical strategy was used to assess in one set of nested models both longitudinal and cross-gender invariance, and…

Longitudinal Surveys of Australian Youth (LSAY) 2009 Cohort: Wave 2 (2010)--Frequency Tables. Technical Report 71B

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This technical paper contains the frequency tables for the LSAY 2009 cohort Wave 2 (2010) data set.

Longitudinal Predictors of Achievement: Achievement History, Family Environment, and Mental Health.

ERIC Educational Resources Information Center

Petersen, Anne C.; Kellam, Sheppard G.

In this seven year longitudinal study predictors of achievement for first graders were measured against actual school achievement of the same students in the seventh and eight grades. Three sets of variables were obtained in the first grade. Achievement history, family environment, and mental health were used as measures. Mental health was…

Positive Parenting Practices Associated with Subsequent Childhood Weight Change

ERIC Educational Resources Information Center

Avula, Rasmi; Gonzalez, Wendy; Shapiro, Cheri J.; Fram, Maryah S.; Beets, Michael W.; Jones, Sonya J.; Blake, Christine E.; Frongillo, Edward A.

2011-01-01

We aimed to identify positive parenting practices that set children on differential weight-trajectories. Parenting practices studied were cognitively stimulating activities, limit-setting, disciplinary practices, and parent warmth. Data from two U.S. national longitudinal data sets and linear and logistic regression were used to examine…

Inclusive Education, Support Provisions and Early Childhood Educational Pathways in the Context of Sweden: A Longitudinal Study

ERIC Educational Resources Information Center

Lundqvist, Johanna; Mara, Allodi Westling; Siljehag, Eva

2015-01-01

The purpose of this study was to investigate the educational pathways of a group of children with and without special educational needs from the last year in preschool to 1st grade. Fifty-six children participated and 65 educational settings were visited. A longitudinal and mixed method approach was adopted. Data was collected via observations,…

National Education Longitudinal Study of 1988. First Follow-Up: School Component Data File User's Manual.

ERIC Educational Resources Information Center

Ingels, Steven J.; And Others

This manual has been produced to familiarize data users with the procedures followed for data collection and processing of the first follow-up component of the National Education Longitudinal Study of 1988 (NELS:88). A corollary objective is to provide the necessary documentation for use of the data file. Use of the data set does not require the…

The Effects of an Undergraduate Programme of Preschool Teaching on Preservice Teachers' Attitudes Towards Early Mathematics Education in Turkey: A Longitudinal Study

ERIC Educational Resources Information Center

Kesicioglu, Oguz Serdar

2015-01-01

The aim of this study is to set forth preservice teachers' attitudes towards early mathematics education. For this purpose, quantitative and qualitative research methods were used conjunctively and the research was planned in accordance with a "screening model". The longitudinal screening model, one of the screening models, was used in…

Interaction between Social/Psychosocial Factors and Genetic Variants on Body Mass Index: A Gene-Environment Interaction Analysis in a Longitudinal Setting.

PubMed

Zhao, Wei; Ware, Erin B; He, Zihuai; Kardia, Sharon L R; Faul, Jessica D; Smith, Jennifer A

2017-09-29

Obesity, which develops over time, is one of the leading causes of chronic diseases such as cardiovascular disease. However, hundreds of BMI (body mass index)-associated genetic loci identified through large-scale genome-wide association studies (GWAS) only explain about 2.7% of BMI variation. Most common human traits are believed to be influenced by both genetic and environmental factors. Past studies suggest a variety of environmental features that are associated with obesity, including socioeconomic status and psychosocial factors. This study combines both gene/regions and environmental factors to explore whether social/psychosocial factors (childhood and adult socioeconomic status, social support, anger, chronic burden, stressful life events, and depressive symptoms) modify the effect of sets of genetic variants on BMI in European American and African American participants in the Health and Retirement Study (HRS). In order to incorporate longitudinal phenotype data collected in the HRS and investigate entire sets of single nucleotide polymorphisms (SNPs) within gene/region simultaneously, we applied a novel set-based test for gene-environment interaction in longitudinal studies (LGEWIS). Childhood socioeconomic status (parental education) was found to modify the genetic effect in the gene/region around SNP rs9540493 on BMI in European Americans in the HRS. The most significant SNP (rs9540488) by childhood socioeconomic status interaction within the rs9540493 gene/region was suggestively replicated in the Multi-Ethnic Study of Atherosclerosis (MESA) ( p = 0.07).

Interaction between Social/Psychosocial Factors and Genetic Variants on Body Mass Index: A Gene-Environment Interaction Analysis in a Longitudinal Setting

PubMed Central

Zhao, Wei; He, Zihuai; Kardia, Sharon L. R.; Faul, Jessica D.

2017-01-01

Obesity, which develops over time, is one of the leading causes of chronic diseases such as cardiovascular disease. However, hundreds of BMI (body mass index)-associated genetic loci identified through large-scale genome-wide association studies (GWAS) only explain about 2.7% of BMI variation. Most common human traits are believed to be influenced by both genetic and environmental factors. Past studies suggest a variety of environmental features that are associated with obesity, including socioeconomic status and psychosocial factors. This study combines both gene/regions and environmental factors to explore whether social/psychosocial factors (childhood and adult socioeconomic status, social support, anger, chronic burden, stressful life events, and depressive symptoms) modify the effect of sets of genetic variants on BMI in European American and African American participants in the Health and Retirement Study (HRS). In order to incorporate longitudinal phenotype data collected in the HRS and investigate entire sets of single nucleotide polymorphisms (SNPs) within gene/region simultaneously, we applied a novel set-based test for gene-environment interaction in longitudinal studies (LGEWIS). Childhood socioeconomic status (parental education) was found to modify the genetic effect in the gene/region around SNP rs9540493 on BMI in European Americans in the HRS. The most significant SNP (rs9540488) by childhood socioeconomic status interaction within the rs9540493 gene/region was suggestively replicated in the Multi-Ethnic Study of Atherosclerosis (MESA) (p = 0.07). PMID:28961216

A longitudinal model for functional connectivity networks using resting-state fMRI.

PubMed

Hart, Brian; Cribben, Ivor; Fiecas, Mark

2018-06-04

Many neuroimaging studies collect functional magnetic resonance imaging (fMRI) data in a longitudinal manner. However, the current fMRI literature lacks a general framework for analyzing functional connectivity (FC) networks in fMRI data obtained from a longitudinal study. In this work, we build a novel longitudinal FC model using a variance components approach. First, for all subjects' visits, we account for the autocorrelation inherent in the fMRI time series data using a non-parametric technique. Second, we use a generalized least squares approach to estimate 1) the within-subject variance component shared across the population, 2) the baseline FC strength, and 3) the FC's longitudinal trend. Our novel method for longitudinal FC networks seeks to account for the within-subject dependence across multiple visits, the variability due to the subjects being sampled from a population, and the autocorrelation present in fMRI time series data, while restricting the number of parameters in order to make the method computationally feasible and stable. We develop a permutation testing procedure to draw valid inference on group differences in the baseline FC network and change in FC over longitudinal time between a set of patients and a comparable set of controls. To examine performance, we run a series of simulations and apply the model to longitudinal fMRI data collected from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Overall, we found no difference in the global FC network between Alzheimer's disease patients and healthy controls, but did find differing local aging patterns in the FC between the left hippocampus and the posterior cingulate cortex. Copyright © 2018 Elsevier Inc. All rights reserved.

The re-identification risk of Canadians from longitudinal demographics

PubMed Central

2011-01-01

Background The public is less willing to allow their personal health information to be disclosed for research purposes if they do not trust researchers and how researchers manage their data. However, the public is more comfortable with their data being used for research if the risk of re-identification is low. There are few studies on the risk of re-identification of Canadians from their basic demographics, and no studies on their risk from their longitudinal data. Our objective was to estimate the risk of re-identification from the basic cross-sectional and longitudinal demographics of Canadians. Methods Uniqueness is a common measure of re-identification risk. Demographic data on a 25% random sample of the population of Montreal were analyzed to estimate population uniqueness on postal code, date of birth, and gender as well as their generalizations, for periods ranging from 1 year to 11 years. Results Almost 98% of the population was unique on full postal code, date of birth and gender: these three variables are effectively a unique identifier for Montrealers. Uniqueness increased for longitudinal data. Considerable generalization was required to reach acceptably low uniqueness levels, especially for longitudinal data. Detailed guidelines and disclosure policies on how to ensure that the re-identification risk is low are provided. Conclusions A large percentage of Montreal residents are unique on basic demographics. For non-longitudinal data sets, the three character postal code, gender, and month/year of birth represent sufficiently low re-identification risk. Data custodians need to generalize their demographic information further for longitudinal data sets. PMID:21696636

A Methodological Review of Statistical Methods for Handling Multilevel Non-Nested Longitudinal Data in Educational Research

ERIC Educational Resources Information Center

Sun, Shuyan; Pan, Wei

2014-01-01

As applications of multilevel modelling in educational research increase, researchers realize that multilevel data collected in many educational settings are often not purely nested. The most common multilevel non-nested data structure is one that involves student mobility in longitudinal studies. This article provides a methodological review of…

Educational Subculture and Dropping out in Higher Education: A Longitudinal Case Study

ERIC Educational Resources Information Center

Venuleo, C.; Mossi, P.; Salvatore, S.

2016-01-01

The paper tests longitudinally the hypothesis that educational subcultures in terms of which students interpret their role and their educational setting affect the probability of dropping out of higher education. A logistic regression model was performed to predict drop out at the beginning of the second academic year for the 823 freshmen of a…

Time Perspective and Identity Formation: Short-Term Longitudinal Dynamics in College Students

ERIC Educational Resources Information Center

Luyckx, Koen; Lens, Willy; Smits, Ilse; Goossens, Luc

2010-01-01

Planning for the future and developing a personalized identity are conceived of as important developmental tasks that adolescents and emerging adults are confronted with on the pathway to adulthood. The present study set out to examine whether both tasks develop in tandem by using a short-term longitudinal dataset consisting of 371 college…

School Attendance Problems and Youth Psychopathology: Structural Cross-Lagged Regression Models in Three Longitudinal Data Sets

ERIC Educational Resources Information Center

Wood, Jeffrey J.; Lynne-Landsman, Sarah D.; Langer, David A.; Wood, Patricia A.; Clark, Shaunna L.; Eddy, J. Mark; Ialongo, Nick

2012-01-01

This study tests a model of reciprocal influences between absenteeism and youth psychopathology using 3 longitudinal datasets (Ns = 20,745, 2,311, and 671). Participants in 1st through 12th grades were interviewed annually or biannually. Measures of psychopathology include self-, parent-, and teacher-report questionnaires. Structural cross-lagged…

[Change settings for visual analyzer of child users of mobile communication: longitudinal study].

PubMed

Khorseva, N I; Grigor'ev, Iu G; Gorbunova, N V

2014-01-01

The paper represents theresults of longitudinal monitoring of the changes in the parameters of simple visual-motor reaction, the visual acuity and the rate of the visual discrimination in the child users of mobile communication, which indicate the multivariability of the possible effects of radiation from mobile phones on the auditory system of children.

Tense over Time: The Longitudinal Course of Tense Acquisition in Children with Specific Language Impairment.

ERIC Educational Resources Information Center

Rice, Mabel L.; Wexler, Kenneth; Hershberger, Scott

1998-01-01

A longitudinal study of 43 typical children (ages 2 to 8) and 21 children with specific language impairments (SLI) found that a diverse set of morphemes share the property of tense marking, that acquisition shows linear and nonlinear components, and that mean length of utterance predicts rate of acquisition. (Author/CR)

A Longitudinal Examination of Risky Sexual Behaviors among Canadian and Italian Adolescents: Considering Individual, Parental, and Friend Characteristics

ERIC Educational Resources Information Center

Boislard P., Marie-Aude; Poulin, Francois; Kiesner, Jeff; Dishion, Thomas J.

2009-01-01

In this study, two longitudinal models of early adolescent risky sexual behaviors (RSB) were compared using a pooled sample of 267 Canadian and Italian adolescents (55% females; 53% Canadians) assessed yearly from grade 8 to 10. We focused on parenting practices (monitoring, control, limit setting), adolescent problem behaviors (antisocial…

Testing the Efficacy of Two New Variants of Recasts with Standard Recasts in Communicative Conversational Settings: An Exploratory Longitudinal Study

ERIC Educational Resources Information Center

Wacha, Richard Charles; Liu, Yeu-Ting

2017-01-01

The purpose of this exploratory longitudinal study was to evaluate the efficacy of two new forms of recasts (i.e., elaborated and paraphrased recasts), each of which was designed to be more in accordance with contested views of input processing. The effectiveness of the two new forms of recasts was compared to that of conventional standard…

Bayesian analysis of longitudinal dyadic data with informative missing data using a dyadic shared-parameter model.

PubMed

Ahn, Jaeil; Morita, Satoshi; Wang, Wenyi; Yuan, Ying

2017-01-01

Analyzing longitudinal dyadic data is a challenging task due to the complicated correlations from repeated measurements and within-dyad interdependence, as well as potentially informative (or non-ignorable) missing data. We propose a dyadic shared-parameter model to analyze longitudinal dyadic data with ordinal outcomes and informative intermittent missing data and dropouts. We model the longitudinal measurement process using a proportional odds model, which accommodates the within-dyad interdependence using the concept of the actor-partner interdependence effects, as well as dyad-specific random effects. We model informative dropouts and intermittent missing data using a transition model, which shares the same set of random effects as the longitudinal measurement model. We evaluate the performance of the proposed method through extensive simulation studies. As our approach relies on some untestable assumptions on the missing data mechanism, we perform sensitivity analyses to evaluate how the analysis results change when the missing data mechanism is misspecified. We demonstrate our method using a longitudinal dyadic study of metastatic breast cancer.

Investigation of 2‐stage meta‐analysis methods for joint longitudinal and time‐to‐event data through simulation and real data application

PubMed Central

Tudur Smith, Catrin; Gueyffier, François; Kolamunnage‐Dona, Ruwanthi

2017-01-01

Background Joint modelling of longitudinal and time‐to‐event data is often preferred over separate longitudinal or time‐to‐event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time‐to‐event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta‐analysis of joint model estimates from multiple studies. Methods We propose a 2‐stage method for meta‐analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta‐analyses of separate longitudinal or time‐to‐event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios. Results Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta‐analytic setting where association exists between the longitudinal and time‐to‐event outcomes. Conclusions Where evidence of association between longitudinal and time‐to‐event outcomes exists, results from joint models over standalone analyses should be pooled in 2‐stage meta‐analyses. PMID:29250814

Alternative Settings--Alternative Teachers? Reflections on Teaching outside the Mainstream

ERIC Educational Resources Information Center

Dyson, Michael; Plunkett, Margaret

2012-01-01

While alternative educational settings in Australia have expanded over the past two decades, there has been little formal research into teacher perceptions of what it means to teach outside the mainstream. This paper outlines part of a longitudinal study involving the School for Student Leadership (SSL), an alternate educational setting in…

Longitudinal Surveys of Australian Youth (LSAY): 2003 Cohort Wave 7 (2009)--Frequency Tables. Technical Report 57B

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2010

2010-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This technical paper contains the frequency tables for the LSAY 2003 cohort Wave 7 (2009) data set. [For the related questionnaire, see ED512164.

Longitudinal Surveys of Australian Youth (LSAY) 2009 Cohort: Wave 3 (2011)--Frequency Tables. Technical Report 72B

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This technical paper contains the frequency tables for the LSAY 2009 cohort Wave 3 (2011) data set. [For the related questionnaire, see ED536306.

Longitudinal Surveys of Australian Youth (LSAY) 2003 Cohort: Wave 7 (2009)--Questionnaire. Technical Report 57A

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2010

2010-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This technical paper contains the questionnaire for the LSAY 2003 cohort Wave 7 (2009) data set. [For the related frequency tables, see ED512163.

Longitudinal Surveys of Australian Youth (LSAY) 2006 Cohort: Wave 6 (2011)--Questionnaire. Technical Report 75A

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This series of documents provides supporting information for the LSAY data set of the 2006 cohort at wave 6 (2011). The document presents the questionnaire for LSAY…

Causal Latent Markov Model for the Comparison of Multiple Treatments in Observational Longitudinal Studies

ERIC Educational Resources Information Center

Bartolucci, Francesco; Pennoni, Fulvia; Vittadini, Giorgio

2016-01-01

We extend to the longitudinal setting a latent class approach that was recently introduced by Lanza, Coffman, and Xu to estimate the causal effect of a treatment. The proposed approach enables an evaluation of multiple treatment effects on subpopulations of individuals from a dynamic perspective, as it relies on a latent Markov (LM) model that is…

Families in a High-Tech Age: Technology Usage Patterns, Work and Family Correlates, and Gender

ERIC Educational Resources Information Center

Chesley, Noelle

2006-01-01

This study analyzes a couple-level ("N" = 581), longitudinal data set of employees to provide evidence about technology use over time, the factors that predict use, and the potential for a spouse to influence an individual's use. Although longitudinal usage patterns suggest a trend toward adoption and use of e-mail, the Internet, cell phones, and…

Sex Differences in the Longitudinal Prediction of Adult Personality.

ERIC Educational Resources Information Center

Sutton-Smith, B.; Rosenberg, B. G.

This paper deals with two sets of data-one that fails to find any long-term sex differences in adults, and another which seems to find such differences. The Berkeley Guidance Study offers longitudinal data in which no variables differentiate between the two sexes at all age levels. From these results, the authors conclude that the normal course of…

The Importance of Longitudinal Studies

NASA Astrophysics Data System (ADS)

Knezek, Patricia

2014-01-01

It has been eight years since the AAS Council unanimously endorsed the document, known as "Equity Now: The Pasadena Recommendations for Gender Equality in Astronomy," in January 2005. This document was the main product of the conference entitled “Women in Astronomy II: Ten Years After” (WIA II), held in June 2003 in Pasadena, CA. One of the key recommendations represented in that document was the need for a longitudinal study of astronomers. It was recognized that in order to understand our own field, how it is evolving, and the impact on individuals, we need to track people over time. I will discuss the fundamental questions that led to the recommendation, and set the stage for the current (ongoing) longitudinal study.

Using Hand Grip Force as a Correlate of Longitudinal Acceleration Comfort for Rapid Transit Trains

PubMed Central

Guo, Beiyuan; Gan, Weide; Fang, Weining

2015-01-01

Longitudinal acceleration comfort is one of the essential metrics used to evaluate the ride comfort of train. The aim of this study was to investigate the effectiveness of using hand grip force as a correlate of longitudinal acceleration comfort of rapid transit trains. In the paper, a motion simulation system was set up and a two-stage experiment was designed to investigate the role of the grip force on the longitudinal comfort of rapid transit trains. The results of the experiment show that the incremental grip force was linearly correlated with the longitudinal acceleration value, while the incremental grip force had no correlation with the direction of the longitudinal acceleration vector. The results also show that the effects of incremental grip force and acceleration duration on the longitudinal comfort of rapid transit trains were significant. Based on multiple regression analysis, a step function model was established to predict the longitudinal comfort of rapid transit trains using the incremental grip force and the acceleration duration. The feasibility and practicably of the model was verified by a field test. Furthermore, a comparative analysis shows that the motion simulation system and the grip force based model were valid to support the laboratory studies on the longitudinal comfort of rapid transit trains. PMID:26147730

Clustering of longitudinal data by using an extended baseline: A new method for treatment efficacy clustering in longitudinal data.

PubMed

Schramm, Catherine; Vial, Céline; Bachoud-Lévi, Anne-Catherine; Katsahian, Sandrine

2018-01-01

Heterogeneity in treatment efficacy is a major concern in clinical trials. Clustering may help to identify the treatment responders and the non-responders. In the context of longitudinal cluster analyses, sample size and variability of the times of measurements are the main issues with the current methods. Here, we propose a new two-step method for the Clustering of Longitudinal data by using an Extended Baseline. The first step relies on a piecewise linear mixed model for repeated measurements with a treatment-time interaction. The second step clusters the random predictions and considers several parametric (model-based) and non-parametric (partitioning, ascendant hierarchical clustering) algorithms. A simulation study compares all options of the clustering of longitudinal data by using an extended baseline method with the latent-class mixed model. The clustering of longitudinal data by using an extended baseline method with the two model-based algorithms was the more robust model. The clustering of longitudinal data by using an extended baseline method with all the non-parametric algorithms failed when there were unequal variances of treatment effect between clusters or when the subgroups had unbalanced sample sizes. The latent-class mixed model failed when the between-patients slope variability is high. Two real data sets on neurodegenerative disease and on obesity illustrate the clustering of longitudinal data by using an extended baseline method and show how clustering may help to identify the marker(s) of the treatment response. The application of the clustering of longitudinal data by using an extended baseline method in exploratory analysis as the first stage before setting up stratified designs can provide a better estimation of treatment effect in future clinical trials.

Returning findings within longitudinal cohort studies: the 1958 birth cohort as an exemplar.

PubMed

Wallace, Susan E; Walker, Neil M; Elliott, Jane

2014-01-01

Population-based, prospective longitudinal cohort studies are considering the issues surrounding returning findings to individuals as a result of genomic and other medical research studies. While guidance is being developed for clinical settings, the process is less clear for those conducting longitudinal research. This paper discusses work conducted on behalf of The UK Cohort and Longitudinal Study Enhancement Resource programme (CLOSER) to examine consent requirements, process considerations and specific examples of potential findings in the context of the 1958 British Birth cohort. Beyond deciding which findings to return, there are questions of whether re-consent is needed and the possible impact on the study, how the feedback process will be managed, and what resources are needed to support that process. Recommendations are made for actions a cohort study should consider taking when making vital decisions regarding returning findings. Any decisions need to be context-specific, arrived at transparently, communicated clearly, and in the best interests of both the participants and the study.

The Feeding Practices and Structure Questionnaire (FPSQ-28): A parsimonious version validated for longitudinal use from 2 to 5 years.

PubMed

Jansen, Elena; Williams, Kate E; Mallan, Kimberley M; Nicholson, Jan M; Daniels, Lynne A

2016-05-01

Prospective studies and intervention evaluations that examine change over time assume that measurement tools measure the same construct at each occasion. In the area of parent-child feeding practices, longitudinal measurement properties of the questionnaires used are rarely verified. To ascertain that measured change in feeding practices reflects true change rather than change in the assessment, structure, or conceptualisation of the constructs over time, this study examined longitudinal measurement invariance of the Feeding Practices and Structure Questionnaire (FPSQ) subscales (9 constructs; 40 items) across 3 time points. Mothers participating in the NOURISH trial reported their feeding practices when children were aged 2, 3.7, and 5 years (N = 404). Confirmatory Factor Analysis (CFA) within a structural equation modelling framework was used. Comparisons of initial cross-sectional models followed by longitudinal modelling of subscales, resulted in the removal of 12 items, including two redundant or poorly performing subscales. The resulting 28-item FPSQ-28 comprised 7 multi-item subscales: Reward for Behaviour, Reward for Eating, Persuasive Feeding, Overt Restriction, Covert Restriction, Structured Meal Setting and Structured Meal Timing. All subscales showed good fit over 3 time points and each displayed at least partial scalar (thresholds equal) longitudinal measurement invariance. We recommend the use of a separate single item indicator to assess the family meal setting. This is the first study to examine longitudinal measurement invariance in a feeding practices questionnaire. Invariance was established, indicating that the subscales of the shortened FPSQ-28 can be used with mothers to validly assess change in 7 feeding constructs in samples of children aged 2-5 years of age. Copyright © 2016 Elsevier Ltd. All rights reserved.

Making an unknown unknown a known unknown: Missing data in longitudinal neuroimaging studies.

PubMed

Matta, Tyler H; Flournoy, John C; Byrne, Michelle L

2017-10-28

The analysis of longitudinal neuroimaging data within the massively univariate framework provides the opportunity to study empirical questions about neurodevelopment. Missing outcome data are an all-to-common feature of any longitudinal study, a feature that, if handled improperly, can reduce statistical power and lead to biased parameter estimates. The goal of this paper is to provide conceptual clarity of the issues and non-issues that arise from analyzing incomplete data in longitudinal studies with particular focus on neuroimaging data. This paper begins with a review of the hierarchy of missing data mechanisms and their relationship to likelihood-based methods, a review that is necessary not just for likelihood-based methods, but also for multiple-imputation methods. Next, the paper provides a series of simulation studies with designs common in longitudinal neuroimaging studies to help illustrate missing data concepts regardless of interpretation. Finally, two applied examples are used to demonstrate the sensitivity of inferences under different missing data assumptions and how this may change the substantive interpretation. The paper concludes with a set of guidelines for analyzing incomplete longitudinal data that can improve the validity of research findings in developmental neuroimaging research. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

ETS Matched Pictures Language Comprehension Task I and II; Technical Report 5. Disadvantaged Children and Their First School Experiences. ETS-Head Start Longitudinal Study. Technical Report Series.

ERIC Educational Resources Information Center

Meissner, Judith A.; And Others

The ETS Matched Pictures test was used in the longitudinal study to measure children's comprehension of certain grammatical features, such as past and future tenses, negation and prepositions. The task materials for both I and II consist of a set of cards, with each card having a pair of black and white pictures. Both pictures in a pair contain…

Characterizing longitudinal health state transitions among heroin, cocaine, and methamphetamine users

PubMed Central

Nosyk, B; Li, L; Evans, E; Huang, D; Min, J; Kerr, T; Brecht, ML; Hser, YI

2014-01-01

Aims Characterize longitudinal patterns of drug use careers and identify determinants of drug use frequency across cohorts of primary heroin, methamphetamine (MA) and cocaine users. Design Pooled analysis of prospective cohort studies. Settings Illicit drug users recruited from community, criminal justice and drug treatment settings in California, USA. Participants We used longitudinal data on from five observational cohort studies featuring primary users of heroin (N=629), cocaine (N=694) and methamphetamine (N=474). The mean duration of follow-up was 20.9 years. Measurements Monthly longitudinal data was arranged according to five health states (incarceration, drug treatment, abstinence, non-daily and daily use). We fitted proportional hazards (PH) frailty models to determine independent differences in successive episode durations. We then executed multi-state Markov (MSM) models to estimate probabilities of transitioning between health states, and the determinants of these transitions. Findings Across primary drug use types, PH frailty models demonstrated durations of daily use diminished in successive episodes over time. MSM models revealed primary stimulant users had more erratic longitudinal patterns of drug use, transitioning more rapidly between periods of treatment, abstinence, non-daily and daily use. MA users exhibited relatively longer durations of high-frequency use. Criminal engagement had a destabilizing effect on health state durations across drug types. Longer incarceration histories were associated with delayed transitions towards cessation. Conclusions PH frailty and MSM modeling techniques provided complementary information on longitudinal patterns of drug abuse. This information can inform clinical practice and policy, and otherwise be used in health economic simulation models, designed to inform resource allocation decisions. PMID:24837584

Longitudinal Surveys of Australian Youth (LSAY) 2003 Cohort: Wave 9 (2011)--Frequency Tables. Technical Report 76B

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This series of documents provides supporting information for the LSAY data set of the 2003 cohort at wave 9 (2011). This document presents the frequency tables for…

Longitudinal Surveys of Australian Youth (LSAY) 2006 Cohort: Wave 6 (2011)--Frequency Tables. Technical Report 75B

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This series of documents provides supporting information for the LSAY data set of the 2006 cohort at wave 6 (2011). This document presents the frequency tables for…

Digital Divides and Socio-Demographic Factors: A Longitudinal Quantitative Study of Internet Users in U.S. from 2000 to 2010

ERIC Educational Resources Information Center

Zhang, Peter H.

2013-01-01

This research attempted to reveal the existence of digital divides, their relationships to users' socio-demographics, and the Internet adoption and usage patterns. It was a longitudinal investigation targeted to the adults eighteen years or older in the household setting from the nation-wide surveys conducted in the United States between 2000…

Longitudinal Retention of Families in the Assessment of a Prevention Program Targeting Adolescent Alcohol and Tobacco Use: The Utility of an Ecological Systems Framework

ERIC Educational Resources Information Center

Jones, Deborah J.; Foster, Sarah E.; Olson, Ardis L.; Forehand, Rex L.; Gaffney, Cecelia A.; Zens, Michael S.; Bau, J. J.

2007-01-01

This study examined the association between ecological context (extrafamilial, familial, child factors) at baseline and longitudinal retention of families in the 36-month assessment of an adolescent alcohol and tobacco use prevention program that was conducted within a pediatric primary care setting. A total of 1,780 families were enrolled at…

Stability and Change in Interests: A Longitudinal Study of Adolescents from Grades 8 through 12

ERIC Educational Resources Information Center

Tracey, Terence J. G.; Robbins, Steven B.; Hofsess, Christy D.

2005-01-01

The pattern of RIASEC interests and academic skills were assessed longitudinally from a large-scale national database at three time points: eight grade, 10th grade, and 12th grade. Validation and cross-validation samples of 1000 males and 1000 females in each set were used to test the pattern of these scores over time relative to mean changes,…

Investigation of 2-stage meta-analysis methods for joint longitudinal and time-to-event data through simulation and real data application.

PubMed

Sudell, Maria; Tudur Smith, Catrin; Gueyffier, François; Kolamunnage-Dona, Ruwanthi

2018-04-15

Joint modelling of longitudinal and time-to-event data is often preferred over separate longitudinal or time-to-event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time-to-event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta-analysis of joint model estimates from multiple studies. We propose a 2-stage method for meta-analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta-analyses of separate longitudinal or time-to-event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios. Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta-analytic setting where association exists between the longitudinal and time-to-event outcomes. Where evidence of association between longitudinal and time-to-event outcomes exists, results from joint models over standalone analyses should be pooled in 2-stage meta-analyses. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.

The Effect of Transition Planning Participation and Goal-Setting on College Enrollment among Youth with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Wei, Xin; Wagner, Mary; Hudson, Laura; Yu, Jennifer W.; Javitz, Harold

2016-01-01

This study used propensity score techniques to assess the relationship between transition planning participation and goal-setting and college enrollment among youth with Autism Spectrum Disorders. Using data from Waves 1 through 5 of the National Longitudinal Transition Study-2, this study found that 2- or 4-year college enrollment rates were…

The Effect of Transition Planning and Goal-Setting on College Enrollment among Youth with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Wei, Xin; Wagner, Mary; Hudson, Laura; Yu, Jennifer W.; Javitz, Harold

2016-01-01

This study used propensity score techniques to assess the relationship between transition planning participation and goal-setting and college enrollment among youth with Autism Spectrum Disorders (ASDs). Using data from waves 1 through 5 of the National Longitudinal Transition Study-2, this study found that 2- or 4-year college enrollment rates…

Early Predictors of ASD in Young Children Using a Nationally Representative Data Set

ERIC Educational Resources Information Center

Jeans, Laurie M.; Santos, Rosa Milagros; Laxman, Daniel J.; McBride, Brent A.; Dyer, W. Justin

2013-01-01

Current clinical diagnosis of Autism Spectrum Disorders (ASD) occurs between 3 and 4 years of age, but increasing evidence indicates that intervention begun earlier may improve outcomes. Using secondary analysis of the Early Childhood Longitudinal Study-Birth Cohort data set, the current study identifies early predictors prior to the diagnosis of…

A longitudinal multilevel CFA-MTMM model for interchangeable and structurally different methods

PubMed Central

Koch, Tobias; Schultze, Martin; Eid, Michael; Geiser, Christian

2014-01-01

One of the key interests in the social sciences is the investigation of change and stability of a given attribute. Although numerous models have been proposed in the past for analyzing longitudinal data including multilevel and/or latent variable modeling approaches, only few modeling approaches have been developed for studying the construct validity in longitudinal multitrait-multimethod (MTMM) measurement designs. The aim of the present study was to extend the spectrum of current longitudinal modeling approaches for MTMM analysis. Specifically, a new longitudinal multilevel CFA-MTMM model for measurement designs with structurally different and interchangeable methods (called Latent-State-Combination-Of-Methods model, LS-COM) is presented. Interchangeable methods are methods that are randomly sampled from a set of equivalent methods (e.g., multiple student ratings for teaching quality), whereas structurally different methods are methods that cannot be easily replaced by one another (e.g., teacher, self-ratings, principle ratings). Results of a simulation study indicate that the parameters and standard errors in the LS-COM model are well recovered even in conditions with only five observations per estimated model parameter. The advantages and limitations of the LS-COM model relative to other longitudinal MTMM modeling approaches are discussed. PMID:24860515

Determining optimal torsional ultrasound power for cataract surgery with automatic longitudinal pulses at maximum vacuum ex vivo.

PubMed

Ronquillo, Cecinio C; Zaugg, Brian; Stagg, Brian; Kirk, Kevin R; Gupta, Isha; Barlow, William R; Pettey, Jeff H; Olson, Randall J

2014-12-01

To determine the optimal longitudinal power settings for Infiniti OZil Intelligent Phaco (IP) at varying torsional amplitude settings; and to test the hypothesis that increasing longitudinal power is more important at lower torsional amplitudes to achieve efficient phacoemulsification. Laboratory investigation. setting: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah. procedure: Individual porcine nuclei were fixed in formalin, then cut into 2.0 mm cubes. Lens cube phacoemulsification was done using OZil IP at 60%, 80%, and 100% torsional amplitude with 0%, 10%, 20%, 30%, 50%, 75%, or 100% longitudinal power. All experiments were done using a 20 gauge 0.9 mm bent reverse bevel phaco tip at constant vacuum (550 mm Hg), aspiration rate (40 mL/min), and bottle height (50 cm). main outcome measure: Complete lens particle phacoemulsification (efficiency). Linear regression analysis showed a significant increase in efficiency with increasing longitudinal power at 60% torsional amplitude (R(2) = 0.7269, P = .01) and 80% torsional amplitude (R(2) = 0.6995, P = .02) but not at 100% amplitude (R(2) = 0.3053, P = .2). Baseline comparison of 60% or 80% vs 100% torsional amplitude without longitudinal power showed increased efficiency at 100% (P = .0004). Increasing longitudinal power to 20% abolished the efficiency difference between 80% vs 100% amplitudes. In contrast, 75% longitudinal power abolished the efficiency difference between 60% vs 100% torsional amplitudes. Results suggest that longitudinal power becomes more critical at increasing phacoemulsification efficiencies at torsional amplitudes less than 100%. Increasing longitudinal power does not further increase efficiency at maximal torsional amplitudes. Copyright © 2014 Elsevier Inc. All rights reserved.

The Merits of Using Longitudinal Mediation

ERIC Educational Resources Information Center

Jose, Paul E.

2016-01-01

Many of the mediation analyses reported in the literature are based on concurrent or single-occasion data sets. The 2 overarching themes of the present article are: Results of concurrent mediations are inherently ambiguous, and researchers would be wise to conduct mediations on longitudinal data sets instead. An example included here demonstrates…

Beliefs about Cancer and Diet among Those Considering Genetic Testing for Colon Cancer

ERIC Educational Resources Information Center

Palmquist, Aunchalee E. L.; Upton, Rachel; Lee, Seungjin; Panter, Abby T.; Hadley, Don W.; Koehly, Laura M.

2011-01-01

Objective: To assess beliefs about the role of diet in cancer prevention among individuals considering genetic testing for Lynch Syndrome. Design: Family-centered, cascade recruitment; baseline assessment of a longitudinal study. Setting: Clinical research setting. Participants: Participants were 390 persons, ages 18 and older, including persons…

Longitudinal construct validity of the minimum data set health status index.

PubMed

Jones, Aaron; Feeny, David; Costa, Andrew P

2018-05-24

The Minimum Data Set Health Status Index (MDS-HSI) is a generic, preference-based health-related quality of life (HRQOL) measure derived by mapping items from the Resident Assessment Instrument - Minimum Data Set (RAI-MDS) assessment onto the Health Utilities Index Mark 2 classification system. While the validity of the MDS-HSI has been examined in cross-sectional settings, the longitudinal validity has not been explored. The objective of this study was to investigate the longitudinal construct validity of the MDS-HSI in a home care population. This study utilized a retrospective cohort of home care patients in the Hamilton-Niagara-Haldimand-Brant health region of Ontario, Canada with at least two RAI-MDS Home Care assessments between January 2010 and December 2014. Convergent validity was assessed by calculating Spearman rank correlations between the change in MDS-HSI and changes in six validated indices of health domains that can be calculated from the RAI-MDS assessment. Known-groups validity was investigated by fitting multivariable linear regression models to estimate the mean change in MDS-HSI associated with clinically important changes in the six health domain indices and 15 disease symptoms from the RAI-MDS Home Care assessment, controlling for age and sex. The cohort contained 25,182 patients with two RAI-MDS Home Care assessments. Spearman correlations between the MDS-HSI change and changes in the health domain indices were all statistically significant and in the hypothesized small to moderate range [0.1 < ρ < 0.5]. Clinically important changes in all of the health domain indices and 13 of the 15 disease symptoms were significantly associated with clinically important changes in the MDS-HSI. The findings of this study support the longitudinal construct validity of the MDS-HSI in home care populations. In addition to evaluating changes in HRQOL among home care patients in clinical research, economic evaluation, and health technology assessment, the MDS-HSI may be used in system-level applications using routinely collected population-level data.

Does the Universal Health Insurance Program Affect Urban-Rural Differences in Health Service Utilization among the Elderly? Evidence from a Longitudinal Study in Taiwan

ERIC Educational Resources Information Center

Liao, Pei-An; Chang, Hung-Hao; Yang, Fang-An

2012-01-01

Purpose: To assess the impact of the introduction of Taiwan's National Health Insurance (NHI) on urban-rural inequality in health service utilization among the elderly. Methods: A longitudinal data set of 1,504 individuals aged 65 and older was constructed from the Survey of Health and Living Status of the Elderly. A difference-in-differences…

European Prevention of Alzheimer's Dementia Registry: Recruitment and prescreening approach for a longitudinal cohort and prevention trials.

PubMed

Vermunt, Lisa; Veal, Colin D; Ter Meulen, Lea; Chrysostomou, Charalambos; van der Flier, Wiesje; Frisoni, Giovanni B; Guessous, Idris; Kivipelto, Miia; Marizzoni, Moira; Martinez-Lage, Pablo; Molinuevo, José Luis; Porteous, David; Ritchie, Karen; Scheltens, Philip; Ousset, Pierre-Jean; Ritchie, Craig W; Luscan, Gerald; Brookes, Anthony J; Visser, Pieter Jelle

2018-06-01

It is a challenge to find participants for Alzheimer's disease (AD) prevention trials within a short period of time. The European Prevention of Alzheimer's Dementia Registry (EPAD) aims to facilitate recruitment by preselecting subjects from ongoing cohort studies. This article introduces this novel approach. A virtual registry, with access to risk factors and biomarkers for AD through minimal data sets of ongoing cohort studies, was set up. To date, ten cohorts have been included in the EPAD. Around 2500 participants have been selected, using variables associated with the risk for AD. Of these, 15% were already recruited in the EPAD longitudinal cohort study, which serves as a trial readiness cohort. This study demonstrates that a virtual registry can be used for the preselection of participants for AD studies. Copyright © 2018 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Children of the National Longitudinal Survey of Youth: A Unique Research Opportunity.

ERIC Educational Resources Information Center

Chase-Lansdale, P. Lindsay; And Others

1991-01-01

This article provides a history of the data set known as "the Children of the National Longitudinal Survey of Youth (NLSY)." Promising research agendas that use the data set are described. These agendas concern maternal employment and child care, adolescent pregnancy and parenthood, divorce, poverty, and multigenerational parenting. (BC)

A Semiparametric Change-Point Regression Model for Longitudinal Observations.

PubMed

Xing, Haipeng; Ying, Zhiliang

2012-12-01

Many longitudinal studies involve relating an outcome process to a set of possibly time-varying covariates, giving rise to the usual regression models for longitudinal data. When the purpose of the study is to investigate the covariate effects when experimental environment undergoes abrupt changes or to locate the periods with different levels of covariate effects, a simple and easy-to-interpret approach is to introduce change-points in regression coefficients. In this connection, we propose a semiparametric change-point regression model, in which the error process (stochastic component) is nonparametric and the baseline mean function (functional part) is completely unspecified, the observation times are allowed to be subject-specific, and the number, locations and magnitudes of change-points are unknown and need to be estimated. We further develop an estimation procedure which combines the recent advance in semiparametric analysis based on counting process argument and multiple change-points inference, and discuss its large sample properties, including consistency and asymptotic normality, under suitable regularity conditions. Simulation results show that the proposed methods work well under a variety of scenarios. An application to a real data set is also given.

Addressing Methodological Challenges in Large Communication Data Sets: Collecting and Coding Longitudinal Interactions in Home Hospice Cancer Care.

PubMed

Reblin, Maija; Clayton, Margaret F; John, Kevin K; Ellington, Lee

2016-07-01

In this article, we present strategies for collecting and coding a large longitudinal communication data set collected across multiple sites, consisting of more than 2000 hours of digital audio recordings from approximately 300 families. We describe our methods within the context of implementing a large-scale study of communication during cancer home hospice nurse visits, but this procedure could be adapted to communication data sets across a wide variety of settings. This research is the first study designed to capture home hospice nurse-caregiver communication, a highly understudied location and type of communication event. We present a detailed example protocol encompassing data collection in the home environment, large-scale, multisite secure data management, the development of theoretically-based communication coding, and strategies for preventing coder drift and ensuring reliability of analyses. Although each of these challenges has the potential to undermine the utility of the data, reliability between coders is often the only issue consistently reported and addressed in the literature. Overall, our approach demonstrates rigor and provides a "how-to" example for managing large, digitally recorded data sets from collection through analysis. These strategies can inform other large-scale health communication research.

Cross-Sectional Analysis of Longitudinal Mediation Processes.

PubMed

O'Laughlin, Kristine D; Martin, Monica J; Ferrer, Emilio

2018-01-01

Statistical mediation analysis can help to identify and explain the mechanisms behind psychological processes. Examining a set of variables for mediation effects is a ubiquitous process in the social sciences literature; however, despite evidence suggesting that cross-sectional data can misrepresent the mediation of longitudinal processes, cross-sectional analyses continue to be used in this manner. Alternative longitudinal mediation models, including those rooted in a structural equation modeling framework (cross-lagged panel, latent growth curve, and latent difference score models) are currently available and may provide a better representation of mediation processes for longitudinal data. The purpose of this paper is twofold: first, we provide a comparison of cross-sectional and longitudinal mediation models; second, we advocate using models to evaluate mediation effects that capture the temporal sequence of the process under study. Two separate empirical examples are presented to illustrate differences in the conclusions drawn from cross-sectional and longitudinal mediation analyses. Findings from these examples yielded substantial differences in interpretations between the cross-sectional and longitudinal mediation models considered here. Based on these observations, researchers should use caution when attempting to use cross-sectional data in place of longitudinal data for mediation analyses.

Prospects for the Comparative Study of International Migration using quasi-longitudinal micro-data

PubMed Central

Liu, Mao-Mei; Creighton, Mathew J.; Riosmena, Fernando; Baizán Mun͂oz, Pau

2017-01-01

BACKGROUND Longitudinal micro-level data about international migration behavior are notoriously difficult to collect, but data collection efforts have become more frequent in recent years. Comparative research of the patterns and processes of international migration, however, remains quite rare, especially that which compares across regions. OBJECTIVE We highlight the promises and difficulties of comparative international migration research, by offering a detailed comparison of two prominent data collection efforts. METHODS We systematically review existing sources of longitudinal and quasi-longitudinal individual-level and household-level data of international migration. We then compare two widely-used data sources: the Mexican Migration Project (MMP) and the Migration between Africa and Europe project (MAFE). RESULTS Data collection efforts are increasingly diverse, yet public accessibility of data remains limited. Also, comparability of data collected across settings can be complicated. In our MMP-MAFE analysis, we show some ways in which comparability can be achieved. CONCLUSIONS A primary roadblock to international comparative research is that, with some exceptions, the public accessibility of data remains low. Even when data is public and surveys are modeled after one another, comparability is not easy due to necessary trade-offs in adapting surveys to local settings and to developments in the field. CONTRIBUTION We demonstrate that, despite great strides in collecting quasi-longitudinal data of international migration, data accessibility still hinders the study of migration. With regards to comparability, our article provides important lessons for future data collection and analysis efforts that could improve comparability and thus advance understanding of the complex dynamics of international migration. PMID:29276429

Seasonal and spatial variation of topside He+ column density obtained from Extreme Ultra Violet Imager onboard the International Space Station

NASA Astrophysics Data System (ADS)

Hozumi, Y.; Saito, A.; Murakami, G.; Yamazaki, A.; Yoshikawa, I.

2016-12-01

The seasonal, longitudinal and latitudinal variations of He+ distribution in the topside ionosphere in 2013 are elucidated with data of He+ resonant scattering obtained by Extreme Ultra Violet Imager (EUVI) onboard the International Space Station (ISS). EUVI provides a data set of the column density of He+ above the ISS orbit altitude. The data set provides a unique opportunity to study He+ distribution in the topside ionosphere from a different perspective of past studies using in-situ measurement data. During the solstice seasons, an enhancement of He+ column density in the winter hemisphere is observed. The magnitude of this hemispheric asymmetry shows a longitudinal variability. Around the June solstice, the hemispheric asymmetry was greater in the longitude sector where the geomagnetic declination angle is negative and smaller in the longitude sector where the geomagnetic declination angle is positive. Around the December solstice, on the other hand, this longitudinal variation of the asymmetry magnitude had opposite tendency. The hemispheric asymmetry of the effective neutral wind well explains this behavior of He+. The field-aligned component of neutral wind in the F-region is varied in longitude under the presence of finite geomagnetic declination angle and large zonal wind. In the equinox seasons, two longitudinal maxima were observed at around 140ºE and 30ºE. The longitudinal variation of the effective neutral wind is a candidate of these two maxima of He+ concentration. These results suggest that the transport of ions in the topside ionosphere is strongly affected by the F-region neutral wind.

Learning from Longitudinal Research in Criminology and the Health Sciences

ERIC Educational Resources Information Center

Vanderstaay, Steven L.

2006-01-01

This article reviews longitudinal research within criminology and the health sciences on the relationship between reading and criminal, delinquent, or antisocial behavior. Longitudinal research in criminology, medicine, and psychology examines the role of reading within a broad set of interactive processes, connecting literacy to public health via…

Trail Making Test Elucidates Neural Substrates of Specific Poststroke Executive Dysfunctions.

PubMed

Muir, Ryan T; Lam, Benjamin; Honjo, Kie; Harry, Robin D; McNeely, Alicia A; Gao, Fu-Qiang; Ramirez, Joel; Scott, Christopher J M; Ganda, Anoop; Zhao, Jiali; Zhou, X Joe; Graham, Simon J; Rangwala, Novena; Gibson, Erin; Lobaugh, Nancy J; Kiss, Alex; Stuss, Donald T; Nyenhuis, David L; Lee, Byung-Chul; Kang, Yeonwook; Black, Sandra E

2015-10-01

Poststroke cognitive impairment is typified by prominent deficits in processing speed and executive function. However, the underlying neuroanatomical substrates of executive deficits are not well understood, and further elucidation is needed. There may be utility in fractionating executive functions to delineate neural substrates. One test amenable to fine delineation is the Trail Making Test (TMT), which emphasizes processing speed (TMT-A) and set shifting (TMT-B-A difference, proportion, quotient scores, and TMT-B set-shifting errors). The TMT was administered to 2 overt ischemic stroke cohorts from a multinational study: (1) a chronic stroke cohort (N=61) and (2) an acute-subacute stroke cohort (N=45). Volumetric quantification of ischemic stroke and white matter hyperintensities was done on magnetic resonance imaging, along with ratings of involvement of cholinergic projections, using the previously published cholinergic hyperintensities projections scale. Damage to the superior longitudinal fasciculus, which colocalizes with some cholinergic projections, was also documented. Multiple linear regression analyses were completed. Although larger infarcts (β=0.37, P<0.0001) were associated with slower processing speed, cholinergic hyperintensities projections scale severity (β=0.39, P<0.0001) was associated with all metrics of set shifting. Left superior longitudinal fasciculus damage, however, was only associated with the difference score (β=0.17, P=0.03). These findings were replicated in both cohorts. Patients with ≥2 TMT-B set-shifting errors also had greater cholinergic hyperintensities projections scale severity. In this multinational stroke cohort study, damage to lateral cholinergic pathways and the superior longitudinal fasciculus emerged as significant neuroanatomical correlates for executive deficits in set shifting. © 2015 American Heart Association, Inc.

LIFESPAN: A tool for the computer-aided design of longitudinal studies

PubMed Central

Brandmaier, Andreas M.; von Oertzen, Timo; Ghisletta, Paolo; Hertzog, Christopher; Lindenberger, Ulman

2015-01-01

Researchers planning a longitudinal study typically search, more or less informally, a multivariate space of possible study designs that include dimensions such as the hypothesized true variance in change, indicator reliability, the number and spacing of measurement occasions, total study time, and sample size. The main search goal is to select a research design that best addresses the guiding questions and hypotheses of the planned study while heeding applicable external conditions and constraints, including time, money, feasibility, and ethical considerations. Because longitudinal study selection ultimately requires optimization under constraints, it is amenable to the general operating principles of optimization in computer-aided design. Based on power equivalence theory (MacCallum et al., 2010; von Oertzen, 2010), we propose a computational framework to promote more systematic searches within the study design space. Starting with an initial design, the proposed framework generates a set of alternative models with equal statistical power to detect hypothesized effects, and delineates trade-off relations among relevant parameters, such as total study time and the number of measurement occasions. We present LIFESPAN (Longitudinal Interactive Front End Study Planner), which implements this framework. LIFESPAN boosts the efficiency, breadth, and precision of the search for optimal longitudinal designs. Its initial version, which is freely available at http://www.brandmaier.de/lifespan, is geared toward the power to detect variance in change as specified in a linear latent growth curve model. PMID:25852596

Longitudinal Reliability of Self-Reported Age at Menarche in Adolescent Girls: Variability across Time and Setting

ERIC Educational Resources Information Center

Dorn, Lorah D.; Sontag-Padilla, Lisa M.; Pabst, Stephanie; Tissot, Abbigail; Susman, Elizabeth J.

2013-01-01

Age at menarche is critical in research and clinical settings, yet there is a dearth of studies examining its reliability in adolescents. We examined age at menarche during adolescence, specifically, (a) average method reliability across 3 years, (b) test-retest reliability between time points and methods, (c) intraindividual variability of…

Setting up an Online Panel Representative of the General Population: The German Internet Panel

ERIC Educational Resources Information Center

Blom, Annelies G.; Gathmann, Christina; Krieger, Ulrich

2015-01-01

This article looks into the processes and outcomes of setting up and maintaining a probability-based longitudinal online survey, which is recruited face-to-face and representative of both the online and the offline population aged 16-75 in Germany. This German Internet Panel studies political and economic attitudes and reform preferences through…

Development of EFL Writing over Three Years in Secondary Education: CLIL and Non-CLIL Settings

ERIC Educational Resources Information Center

Gené-Gil, Maria; Juan-Garau, Maria; Salazar-Noguera, Joana

2015-01-01

Research on writing development in content and language integrated learning (CLIL) settings is still inconclusive. This study intends to make a contribution in this respect by presenting longitudinal findings on the development of written complexity, accuracy and fluency (CAF) in secondary education CLIL and non-CLIL learners. Participants in the…

Estimating the Effects of Parental Divorce and Death With Fixed Effects Models.

PubMed

Amato, Paul R; Anthony, Christopher J

2014-04-01

The authors used child fixed effects models to estimate the effects of parental divorce and death on a variety of outcomes using 2 large national data sets: (a) the Early Childhood Longitudinal Study, Kindergarten Cohort (kindergarten through the 5th grade) and (b) the National Educational Longitudinal Study (8th grade to the senior year of high school). In both data sets, divorce and death were associated with multiple negative outcomes among children. Although evidence for a causal effect of divorce on children was reasonably strong, effect sizes were small in magnitude. A second analysis revealed a substantial degree of variability in children's outcomes following parental divorce, with some children declining, others improving, and most not changing at all. The estimated effects of divorce appeared to be strongest among children with the highest propensity to experience parental divorce.

Assessing the goodness-of-fit of the Laird and Ware model--an example: the Jimma Infant Survival Differential Longitudinal Study.

PubMed

Lesaffre, E; Asefa, M; Verbeke, G

1999-04-15

The Jimma Infant Survival Differential Longitudinal Study is an Ethiopian study, set up to establish risk factors affecting infant survival and to investigate socio-economic, maternal and infant-rearing factors that contribute most to the child's early survival. Here, a subgroup of about 1500 children born in Jimma town is examined for their first year's weight gain. Of special interest is the impact of certain cultural practices like uvulectomy, milk teeth extraction and butter swallowing, on child's weight gain; these have never been thoroughly investigated in any study. In this context, the linear mixed model (Laird and Ware) is employed. The purpose of this paper is to illustrate the practical issues when constructing the longitudinal model. Recently developed diagnostics will be used herefor. Finally, special attention will be paid to the two-stage interpretation of the linear mixed model.

New trends in gender and mathematics performance: a meta-analysis.

PubMed

Lindberg, Sara M; Hyde, Janet Shibley; Petersen, Jennifer L; Linn, Marcia C

2010-11-01

In this article, we use meta-analysis to analyze gender differences in recent studies of mathematics performance. First, we meta-analyzed data from 242 studies published between 1990 and 2007, representing the testing of 1,286,350 people. Overall, d = 0.05, indicating no gender difference, and variance ratio = 1.08, indicating nearly equal male and female variances. Second, we analyzed data from large data sets based on probability sampling of U.S. adolescents over the past 20 years: the National Longitudinal Surveys of Youth, the National Education Longitudinal Study of 1988, the Longitudinal Study of American Youth, and the National Assessment of Educational Progress. Effect sizes for the gender difference ranged between -0.15 and +0.22. Variance ratios ranged from 0.88 to 1.34. Taken together, these findings support the view that males and females perform similarly in mathematics.

Longitudinal Changes in Serum Glucose Levels are Associated with Metabolic Changes in Alzheimer's Disease Related Brain Regions.

PubMed

Burns, Christine M; Kaszniak, Alfred W; Chen, Kewei; Lee, Wendy; Bandy, Daniel J; Caselli, Richard J; Reiman, Eric M

2018-01-01

The association between longitudinal changes in serum glucose level and longitudinal changes in [18F] Fluorodeoxyglucose-PET (FDG PET) measurements of Alzheimer's disease (AD) risk are unknown. To investigate whether variation in serum glucose levels across time are associated with changes in FDG PET measurements of cerebral metabolic rate for glucose (rCMRgl) in brain regions preferentially affected by Alzheimer's disease (AD). Participants are a subset of a prospective cohort study investigating FDG PET, apolipoprotein E (APOE) ɛ4, and risk for AD which includes data from baseline, interim, and follow up visits over 4.4±1.0-years. An automated brain-mapping algorithm was utilized to characterize and compare associations between longitudinal changes in serum glucose levels and longitudinal changes in rCMRgl. This study included 80 adults aged 61.5±5 years, including 38 carriers and 42 non-carriers of the APOE ɛ4 allele. Longitudinal increases in serum glucose levels were associated with longitudinal CMRgl decline in the vicinity of parietotemporal, precuneus/posterior cingulate, and prefrontal brain regions preferentially affected by AD (p < 0.05, corrected for multiple comparisons). Findings remained significant when controlled for APOE ɛ4 status and baseline and advancing age. Additional studies are needed to clarify and confirm the relationship between longitudinal changes in peripheral glucose and FDG PET measurements of AD risk. Future findings will set the stage on the use of FDG PET in the evaluation of possible interventions that target risk factors for the development of AD.

Longitudinal Study of Body Mass Index in Young Males and the Transition to Fatherhood

PubMed Central

Garfield, Craig F.; Duncan, Greg; Gutina, Anna; Rutsohn, Joshua; McDade, Thomas W.; Adam, Emma K.; Coley, Rebekah Levine; Chase-Lansdale, P. Lindsay

2017-01-01

Despite a growing understanding that the social determinants of health have an impact on body mass index (BMI), the role of fatherhood on young men’s BMI is understudied. This longitudinal study examines BMI in young men over time as they transition from adolescence into fatherhood in a nationally representative sample. Data from all four waves of the National Longitudinal Study of Adolescent Health supported a 20-year longitudinal analysis of 10,253 men beginning in 1994. A “fatherhood-year” data set was created and changes in BMI were examined based on fatherhood status (nonfather, nonresident father, resident father), fatherhood years, and covariates. Though age is positively associated with BMI over all years for all men, comparing nonresident and resident fathers with nonfathers reveals different trajectories based on fatherhood status. Entrance into fatherhood is associated with an increase in BMI trajectory for both nonresident and resident fathers, while nonfathers exhibit a decrease over the same period. In this longitudinal, population-based study, fatherhood and residence status play a role in men’s BMI. Designing obesity prevention interventions for young men that begin in adolescence and carry through young adulthood should target the distinctive needs of these populations, potentially improving their health outcomes. PMID:26198724

Longitudinal Course of Depression Scores with and without Insomnia in Non-Depressed Individuals: A 6-Year Follow-Up Longitudinal Study in a Korean Cohort

PubMed Central

Suh, Sooyeon; Kim, Hyun; Yang, Hae-Chung; Cho, Eo Rin; Lee, Seung Ku; Shin, Chol

2013-01-01

Study Objective: This is a population-based longitudinal study that followed insomnia symptoms over a 6-year period in non-depressed individuals. The purpose of the study was to (1) investigate the longitudinal course of depression based on number of insomnia episodes; and (2) describe longitudinal associations between insomnia and depression, and insomnia and suicidal ideation. Design: Population-based longitudinal study. Setting: Community-based sample from the Korean Genome and Epidemiology Study (KoGES). Participants: 1,282 non-depressed individuals (44% male, mean age 52.3 ± 7.14 years) Measurements and Results: This study prospectively assessed insomnia, depression, and suicidal ideation with 4 time points. Individuals were classified into no insomnia (NI), single episode insomnia (SEI), and persistent insomnia (PI; ≥ insomnia at 2+ time points) groups based on number of times insomnia was indicated. Mixed effects modeling indicated that depression scores increased significantly faster in the PI group compared to the NI (P < 0.001) and SEI (P = 0.02) groups. Additionally, the PI group had significantly increased odds of depression as compared to NI or SEI (OR 2.44, P = 0.001) groups, with 18.7% meeting criteria for depression compared to the NI (5.3%) and SEI (11.6%) groups at end point. The PI group also had significantly increased odds of suicidal ideation as compared to NI or SEI (OR 1.86, P = 0.002) groups. Conclusions: Persistent insomnia significantly increases the rate in which depression occurs over time in non-depressed individuals, which ultimately leads to higher risk for depression. Additionally, having persistent insomnia also increased the risk of suicidal ideation. Citation: Suh S; Kim H; Yang HC; Cho ER; Lee SK; Shin C. Longitudinal course of depression scores with and without insomnia in non-depressed individuals: a 6-year follow-up longitudinal study in a Korean cohort. SLEEP 2013;36(3):369-376. PMID:23449814

Jeans instability of rotating magnetized quantum plasma: Influence of radiation

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

Joshi, H., E-mail: hjoshi8525@yahoo.com; Pensia, R. K.

2015-07-31

The effect of radiative heat-loss function and rotation on the Jeans instability of quantum plasma is investigated. The basic set of equations for this problem is constructed by considering quantum magnetohydrodynamic (QMHD) model. Using normal mode analysis, the general dispersion relation is obtained. This dispersion relation is studied in both, longitudinal and transverse direction of propagations. In both case of longitudinal and transverse direction of propagation, the Jeans instability criterion is modified due to presence of radiative heat-loss function and quantum correction.

Longitudinal stability in relation to the use of an automatic pilot

NASA Technical Reports Server (NTRS)

Klemin, Alexander; Pepper, Perry A; Wittner, Howard A

1938-01-01

The effect of restraint in pitching introduced by an automatic pilot upon the longitudinal stability of an airplane has been studied. Customary simplifying assumptions have been made in setting down the equations of motion, and the results of computations based on the simplified equations are presented to show the effect of an automatic pilot installed in an airplane of known dimensions and characteristics. The equations developed have been applied by making calculations for a Clark biplane and a Fairchild 22 monoplane.

Joint model-based clustering of nonlinear longitudinal trajectories and associated time-to-event data analysis, linked by latent class membership: with application to AIDS clinical studies.

PubMed

Huang, Yangxin; Lu, Xiaosun; Chen, Jiaqing; Liang, Juan; Zangmeister, Miriam

2017-10-27

Longitudinal and time-to-event data are often observed together. Finite mixture models are currently used to analyze nonlinear heterogeneous longitudinal data, which, by releasing the homogeneity restriction of nonlinear mixed-effects (NLME) models, can cluster individuals into one of the pre-specified classes with class membership probabilities. This clustering may have clinical significance, and be associated with clinically important time-to-event data. This article develops a joint modeling approach to a finite mixture of NLME models for longitudinal data and proportional hazard Cox model for time-to-event data, linked by individual latent class indicators, under a Bayesian framework. The proposed joint models and method are applied to a real AIDS clinical trial data set, followed by simulation studies to assess the performance of the proposed joint model and a naive two-step model, in which finite mixture model and Cox model are fitted separately.

Application of pattern mixture models to address missing data in longitudinal data analysis using SPSS.

PubMed

Son, Heesook; Friedmann, Erika; Thomas, Sue A

2012-01-01

Longitudinal studies are used in nursing research to examine changes over time in health indicators. Traditional approaches to longitudinal analysis of means, such as analysis of variance with repeated measures, are limited to analyzing complete cases. This limitation can lead to biased results due to withdrawal or data omission bias or to imputation of missing data, which can lead to bias toward the null if data are not missing completely at random. Pattern mixture models are useful to evaluate the informativeness of missing data and to adjust linear mixed model (LMM) analyses if missing data are informative. The aim of this study was to provide an example of statistical procedures for applying a pattern mixture model to evaluate the informativeness of missing data and conduct analyses of data with informative missingness in longitudinal studies using SPSS. The data set from the Patients' and Families' Psychological Response to Home Automated External Defibrillator Trial was used as an example to examine informativeness of missing data with pattern mixture models and to use a missing data pattern in analysis of longitudinal data. Prevention of withdrawal bias, omitted data bias, and bias toward the null in longitudinal LMMs requires the assessment of the informativeness of the occurrence of missing data. Missing data patterns can be incorporated as fixed effects into LMMs to evaluate the contribution of the presence of informative missingness to and control for the effects of missingness on outcomes. Pattern mixture models are a useful method to address the presence and effect of informative missingness in longitudinal studies.

The Brain Health Registry: An internet-based platform for recruitment, assessment, and longitudinal monitoring of participants for neuroscience studies.

PubMed

Weiner, Michael W; Nosheny, Rachel; Camacho, Monica; Truran-Sacrey, Diana; Mackin, R Scott; Flenniken, Derek; Ulbricht, Aaron; Insel, Philip; Finley, Shannon; Fockler, Juliet; Veitch, Dallas

2018-05-08

Recruitment, assessment, and longitudinal monitoring of participants for neuroscience studies and clinical trials limit the development of new treatments. Widespread Internet use allows data capture from participants in an unsupervised setting. The Brain Health Registry, a website and online registry, collects data from participants and their study partners. The Brain Health Registry obtains self and study partner report questionnaires and neuropsychological data, including the Cogstate Brief Battery, Lumos Labs Neurocognitive Performance Test, and MemTrax Memory Test. Participants provide informed consent before participation. Baseline and longitudinal data were obtained from nearly 57,000 and 28,000 participants, respectively. Over 18,800 participants were referred to, and nearly 1800 were enrolled in, clinical Alzheimer's disease and aging studies, including five observational studies and seven intervention trials. Online assessments of participants and study partners provide useful information at relatively low cost for neuroscience studies and clinical trials and may ultimately be used in routine clinical practice. Copyright © 2018 the Alzheimer's Association. All rights reserved.

The impact of extended longitudinal observation on the assessment of personality disorders.

PubMed

Pedersen, G; Karterud, S; Hummelen, B; Wilberg, T

2013-11-01

Multiple sources of information are necessary for a valid assessment of personality disorders (PDs). This study investigates the impact of longitudinal observation. The sample comprised 1217 patients from 15 different treatment units. PDs were assessed at admission to treatment using the Structured Clinical Interview for DSM-IV Axis II Personality Disorders (SCID-II) and additional clinical information (best estimate diagnosis). After approximately 18 weeks of treatment, the SCID-II protocols were re-examined at clinical conferences and the diagnostic status reassessed on the basis of longitudinal observations in multiple group situations (longitudinal, expert, all data principle). Using this procedure, 78% of the patients' diagnostic criteria sets were changed, and 32% of patients' diagnostic statuses were changed. Many (32%) patients who were evaluated initially as not having a PD received a PD diagnosis after re-examination. The information provided by customary clinical assessment has important limitations, and longitudinal observation provides additional information that may change the diagnostic status in approximately one-third of PD cases. Copyright © 2013 John Wiley & Sons, Ltd.

Analytical investigation of the dynamics of tethered constellations in earth orbit

NASA Technical Reports Server (NTRS)

Lorenzini, Enrico C.; Gullahorn, Gordon E.; Estes, Robert D.

1988-01-01

This Quarterly Report on Tethering in Earth Orbit deals with three topics: (1) Investigation of the propagation of longitudinal and transverse waves along the upper tether. Specifically, the upper tether is modeled as three massive platforms connected by two perfectly elastic continua (tether segments). The tether attachment point to the station is assumed to vibrate both longitudinally and transversely at a given frequency. Longitudinal and transverse waves propagate along the tethers affecting the acceleration levels at the elevator and at the upper platform. The displacement and acceleration frequency-response functions at the elevator and at the upper platform are computed for both longitudinal and transverse waves. An analysis to optimize the damping time of the longitudinal dampers is also carried out in order to select optimal parameters. The analytical evaluation of the performance of tuned vs. detuned longitudinal dampers is also part of this analysis. (2) The use of the Shuttle primary Reaction Control System (RCS) thrusters for blowing away a recoiling broken tether is discussed. A microcomputer system was set up to support this operation. (3) Most of the effort in the tether plasma physics study was devoted to software development. A particle simulation code has been integrated into the Macintosh II computer system and will be utilized for studying the physics of hollow cathodes.

Long-Term Outcomes of Services for Two Persons with Significant Disabilities with Differing Educational Experiences: A Qualitative Consideration of the Impact of Educational Experiences

ERIC Educational Resources Information Center

Ryndak, Diane Lea; Ward, Terri; Alper, Sandra; Montgomery, Jennifer Wilson; Storch, Jill F.

2010-01-01

Though research exists related to effective services in inclusive general education settings for students with significant disabilities, there are no longitudinal investigations of adult outcomes for persons with significant disabilities who received services in inclusive general education settings. This study uses qualitative methods to describe…

The Role of Age and Setting in Adolescents' First Drinking Experience for Predicting College Problem Drinking

ERIC Educational Resources Information Center

Yaeger, Jeffrey P.; Moreno, Megan A.

2017-01-01

Objective: The purpose of this study was to determine the reliability of longitudinally reporting age at first drink (AFD), and to test AFD and setting of first drink (SFD) as predictors of collegiate problem drinking. Participants: 338 first-year college students were interviewed multiple times during their first academic year, from May 2011…

The development of video game enjoyment in a role playing game.

PubMed

Wirth, Werner; Ryffel, Fabian; von Pape, Thilo; Karnowski, Veronika

2013-04-01

This study examines the development of video game enjoyment over time. The results of a longitudinal study (N=62) show that enjoyment increases over several sessions. Moreover, results of a multilevel regression model indicate a causal link between the dependent variable video game enjoyment and the predictor variables exploratory behavior, spatial presence, competence, suspense and solution, and simulated experiences of life. These findings are important for video game research because they reveal the antecedents of video game enjoyment in a real-world longitudinal setting. Results are discussed in terms of the dynamics of video game enjoyment under real-world conditions.

Analyzing the Behavioral Differences between Students of Different Genders, Prior Knowledge and Learning Performance with an Educational MMORPG: A Longitudinal Case Study in an Elementary School

ERIC Educational Resources Information Center

Hou, Huei-Tse

2013-01-01

Many researchers have studied the effects of game-based learning (GBL) (eg, Annetta, Minogu, Holmes & Cheng, 2009; Kiili, 2007). However, empirical process analyses of long-term applications of GBL in a school setting are much less common. A process analysis of GBL in a school setting allows us to better understand the role of games in…

Meta-Analysis of Effect Sizes Reported at Multiple Time Points Using General Linear Mixed Model.

PubMed

Musekiwa, Alfred; Manda, Samuel O M; Mwambi, Henry G; Chen, Ding-Geng

2016-01-01

Meta-analysis of longitudinal studies combines effect sizes measured at pre-determined time points. The most common approach involves performing separate univariate meta-analyses at individual time points. This simplistic approach ignores dependence between longitudinal effect sizes, which might result in less precise parameter estimates. In this paper, we show how to conduct a meta-analysis of longitudinal effect sizes where we contrast different covariance structures for dependence between effect sizes, both within and between studies. We propose new combinations of covariance structures for the dependence between effect size and utilize a practical example involving meta-analysis of 17 trials comparing postoperative treatments for a type of cancer, where survival is measured at 6, 12, 18 and 24 months post randomization. Although the results from this particular data set show the benefit of accounting for within-study serial correlation between effect sizes, simulations are required to confirm these results.

Examining Procrastination Across Multiple Goal Stages: A Longitudinal Study of Temporal Motivation Theory

PubMed Central

Steel, Piers; Svartdal, Frode; Thundiyil, Tomas; Brothen, Thomas

2018-01-01

Procrastination is among the most common of motivational failures, putting off despite expecting to be worse off. We examine this dynamic phenomenon in a detailed and realistic longitudinal design (Study 1) as well as in a large correlational data set (N = 7400; Study 2). The results are largely consistent with temporal motivation theory. People’s pacing style reflects a hyperbolic curve, with the steepness of the curve predicted by self-reported procrastination. Procrastination is related to intention-action gaps, but not intentions. Procrastinators are susceptible to proximity of temptation and to the temporal separation between their intention and the planned act; the more distal, the greater the gap. Critical self-regulatory skills in explaining procrastination are attention control, energy regulation and automaticity, accounting for 74% of the variance. Future research using this design is recommended, as it provides an almost ideal blend of realism and detailed longitudinal assessment. PMID:29666590

Examining Procrastination Across Multiple Goal Stages: A Longitudinal Study of Temporal Motivation Theory.

PubMed

Steel, Piers; Svartdal, Frode; Thundiyil, Tomas; Brothen, Thomas

2018-01-01

Procrastination is among the most common of motivational failures, putting off despite expecting to be worse off. We examine this dynamic phenomenon in a detailed and realistic longitudinal design (Study 1) as well as in a large correlational data set ( N = 7400; Study 2). The results are largely consistent with temporal motivation theory. People's pacing style reflects a hyperbolic curve, with the steepness of the curve predicted by self-reported procrastination. Procrastination is related to intention-action gaps, but not intentions. Procrastinators are susceptible to proximity of temptation and to the temporal separation between their intention and the planned act; the more distal, the greater the gap. Critical self-regulatory skills in explaining procrastination are attention control, energy regulation and automaticity, accounting for 74% of the variance. Future research using this design is recommended, as it provides an almost ideal blend of realism and detailed longitudinal assessment.

Self-Concept Predicts Academic Achievement Across Levels of the Achievement Distribution: Domain Specificity for Math and Reading.

PubMed

Susperreguy, Maria Ines; Davis-Kean, Pamela E; Duckworth, Kathryn; Chen, Meichu

2017-09-18

This study examines whether self-concept of ability in math and reading predicts later math and reading attainment across different levels of achievement. Data from three large-scale longitudinal data sets, the Avon Longitudinal Study of Parents and Children, National Institute of Child Health and Human Development-Study of Early Child Care and Youth Development, and Panel Study of Income Dynamics-Child Development Supplement, were used to answer this question by employing quantile regression analyses. After controlling for demographic variables, child characteristics, and early ability, the findings indicate that self-concept of ability in math and reading predicts later achievement in each respective domain across all quantile levels of achievement. These results were replicated across the three data sets representing different populations and provide robust evidence for the role of self-concept of ability in understanding achievement from early childhood to adolescence across the spectrum of performance (low to high). © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Estimating the Effects of Parental Divorce and Death With Fixed Effects Models

PubMed Central

Amato, Paul R.; Anthony, Christopher J.

2014-01-01

The authors used child fixed effects models to estimate the effects of parental divorce and death on a variety of outcomes using 2 large national data sets: (a) the Early Childhood Longitudinal Study, Kindergarten Cohort (kindergarten through the 5th grade) and (b) the National Educational Longitudinal Study (8th grade to the senior year of high school). In both data sets, divorce and death were associated with multiple negative outcomes among children. Although evidence for a causal effect of divorce on children was reasonably strong, effect sizes were small in magnitude. A second analysis revealed a substantial degree of variability in children’s outcomes following parental divorce, with some children declining, others improving, and most not changing at all. The estimated effects of divorce appeared to be strongest among children with the highest propensity to experience parental divorce. PMID:24659827

STRUCTURAL AND CONNECTOMIC NEUROIMAGING FOR THE PERSONALIZED STUDY OF LONGITUDINAL ALTERATIONS IN CORTICAL SHAPE, THICKNESS AND CONNECTIVITY AFTER TRAUMATIC BRAIN INJURY

PubMed Central

Irimia, A.; Goh, S.-Y. M.; Torgerson, C. M.; Vespa, P. M.; Van Horn, J. D.

2014-01-01

The integration of longitudinal brain structure analysis with neurointensive care strategies continues to be a substantial difficulty facing the traumatic brain injury (TBI) research community. For patient-tailored case analysis, it remains challenging to establish how lesion profile modulates longitudinal changes in cortical structure and connectivity, as well as how these changes lead to behavioral, cognitive and neural dysfunction. Additionally, despite the clinical potential of morphometric and connectomic studies, few analytic tools are available for their study in TBI. Here we review the state of the art in structural and connectomic neuroimaging for the study of TBI and illustrate a set of recently-developed, patient-tailored approaches for the study of TBI-related brain atrophy and alterations in morphometry as well as inter-regional connectivity. The ability of such techniques to quantify how injury modulates longitudinal changes in cortical shape, structure and circuitry is highlighted. Quantitative approaches such as these can be used to assess and monitor the clinical condition and evolution of TBI victims, and can have substantial translational impact, especially when used in conjunction with measures of neuropsychological function. PMID:24844173

Health and aging: development of the Irish Longitudinal Study on Ageing health assessment.

PubMed

Cronin, Hilary; O'Regan, Clare; Finucane, Ciaran; Kearney, Patricia; Kenny, Rose Anne

2013-05-01

To assist researchers planning studies similar to The Irish Longitudinal Study on Ageing (TILDA), concerning the development of the health assessment component, to promote use of the archived data set, to inform researchers of the methods employed, and to complement the accompanying article on normative values. Prospective, longitudinal study of older adults. Republic of Ireland. Eight thousand five hundred four community-dwelling adults who participated in wave 1 of the TILDA study. The main areas of focus for the TILDA health assessments are neurocardiovascular instability, locomotion, and vision. The article describes the scientific rationale for the choice of assessments and seeks to determine the potential advantages of incorporating novel biomeasures and technologies in population-based studies to advance understanding of aging-related disorders. The detailed description of the physical measures will facilitate cross-national comparative research and put into context the normative values outlined in the subsequent article. © 2013, Copyright the Authors Journal compilation © 2013, The American Geriatrics Society.

The natural course of anxiety disorders in the elderly: a systematic review of longitudinal trials.

PubMed

Sami, Musa Basseer; Nilforooshan, Ramin

2015-07-01

The anxiety disorders are a prevalent mental health problem in older age with a considerable impact on quality of life. Until recently there have been few longitudinal studies on anxiety in this age group, consequently most of the evidence to date has been cross-sectional in nature. We undertook a literature search of Medline, PsycINFO, the Cochrane trials database and the TRIP medical database to identify longitudinal studies which would help elucidate natural history and prognosis of anxiety disorders in the elderly. We identified 12 papers of 10 longitudinal studies in our Review. This represented 34,691 older age participants with 5,199 with anxiety disorders including anxious depression and 3,532 individuals with depression without anxiety. Relapse rates of anxiety disorders are high over 6 year follow-up with considerable migration to mixed anxiety-depression and pure depressive mood episodes. Mixed anxiety-depression appears to be a poorer prognostic state than pure anxiety or pure depression with higher relapse rates across studies. In community settings treatment rates are low with 7-44% of the anxious elderly treated on antidepressant medications. To our knowledge this is the first Systematic Review of longitudinal trials of anxiety disorders in older people. Major longitudinal studies of the anxious elderly are establishing the high risk of relapse and persistence alongside the progression to depression and anxiety depression states. There remains considerable under-treatment in community studies. Specialist assessment and treatment and major public health awareness of the challenges of anxiety disorders in the elderly are required.

Causal mediation analysis for longitudinal data with exogenous exposure

PubMed Central

Bind, M.-A. C.; Vanderweele, T. J.; Coull, B. A.; Schwartz, J. D.

2016-01-01

Mediation analysis is a valuable approach to examine pathways in epidemiological research. Prospective cohort studies are often conducted to study biological mechanisms and often collect longitudinal measurements on each participant. Mediation formulae for longitudinal data have been developed. Here, we formalize the natural direct and indirect effects using a causal framework with potential outcomes that allows for an interaction between the exposure and the mediator. To allow different types of longitudinal measures of the mediator and outcome, we assume two generalized mixed-effects models for both the mediator and the outcome. The model for the mediator has subject-specific random intercepts and random exposure slopes for each cluster, and the outcome model has random intercepts and random slopes for the exposure, the mediator, and their interaction. We also expand our approach to settings with multiple mediators and derive the mediated effects, jointly through all mediators. Our method requires the absence of time-varying confounding with respect to the exposure and the mediator. This assumption is achieved in settings with exogenous exposure and mediator, especially when exposure and mediator are not affected by variables measured at earlier time points. We apply the methodology to data from the Normative Aging Study and estimate the direct and indirect effects, via DNA methylation, of air pollution, and temperature on intercellular adhesion molecule 1 (ICAM-1) protein levels. Our results suggest that air pollution and temperature have a direct effect on ICAM-1 protein levels (i.e. not through a change in ICAM-1 DNA methylation) and that temperature has an indirect effect via a change in ICAM-1 DNA methylation. PMID:26272993

Does informal caregiving affect self-esteem? Results from a population-based study of individuals aged 40 and over in Germany from 2002 to 2014.

PubMed

Hajek, André; König, Hans-Helmut

2017-11-29

While it is known that informal caregiving is associated with care-derived self-esteem cross-sectionally, little is known about the impact of informal caregiving on general self-esteem longitudinally. Thus, we aimed at examining whether informal caregiving affects general self-esteem using a longitudinal approach. Data were gathered from a population-based sample of community-dwelling individuals aged 40 and over in Germany from 2002 to 2014 (n = 21 271). General self-esteem was quantified using the Rosenberg scale. Individuals were asked whether they provide informal care regularly. Fixed effects regressions showed no significant effect of informal caregiving on general self-esteem longitudinally. General self-esteem decreased with increasing morbidity, increasing age, decreasing social ties, whereas it was not associated with changes in employment status, marital status and body mass index. Additional models showed that decreases in self-esteem were associated with decreases in functional health and increases in depressive symptoms. Our longitudinal study emphasises that the occurrence of informal caregiving did not affect general self-esteem longitudinally. Further research is needed in other cultural settings using panel data methods. © 2017 Nordic College of Caring Science.

Measuring housing quality in the absence of a monetized real estate market.

PubMed

Rindfuss, Ronald R; Piotrowski, Martin; Thongthai, Varachai; Prasartkul, Pramote

2007-03-01

Measuring housing quality or value or both has been a weak component of demographic and development research in less developed countries that lack an active real estate (housing) market. We describe a new method based on a standardized subjective rating process. It is designed to be used in settings that do not have an active, monetized housing market. The method is applied in an ongoing longitudinal study in north-east Thailand and could be straightforwardly used in many other settings. We develop a conceptual model of the process whereby households come to reside in high-quality or low-quality housing units. We use this theoretical model in conjunction with longitudinal data to show that the new method of measuring housing quality behaves as theoretically expected, thus providing evidence of face validity.

Early School Adjustment and Educational Attainment

ERIC Educational Resources Information Center

Magnuson, Katherine; Duncan, Greg J.; Lee, Kenneth T. H.; Metzger, Molly W.

2016-01-01

Although school attainment is a cumulative process combining mastery of both academic and behavioral skills, most studies have offered only a piecemeal view of the associations between middle-childhood capacities and subsequent schooling outcomes. Using a 20-year longitudinal data set, this study estimates the association between children's…

Predicting Second Grade Listening Comprehension Using Prekindergarten Measures

ERIC Educational Resources Information Center

Alonzo, Crystle N.; Yeomans-Maldonado, Gloria; Murphy, Kimberly A.; Bevens, Beau

2016-01-01

Purpose: The purpose of this study was to determine prekindergarten predictors of listening comprehension in second grade. Methods: Within a large, 5-year longitudinal study, children progressing from prekindergarten to second grade were administered a comprehensive set of prekindergarten measures of foundational language skills (vocabulary and…

The validity of a professional competence tool for physiotherapy students in simulation-based clinical education: a Rasch analysis.

PubMed

Judd, Belinda K; Scanlan, Justin N; Alison, Jennifer A; Waters, Donna; Gordon, Christopher J

2016-08-05

Despite the recent widespread adoption of simulation in clinical education in physiotherapy, there is a lack of validated tools for assessment in this setting. The Assessment of Physiotherapy Practice (APP) is a comprehensive tool used in clinical placement settings in Australia to measure professional competence of physiotherapy students. The aim of the study was to evaluate the validity of the APP for student assessment in simulation settings. A total of 1260 APPs were collected, 971 from students in simulation and 289 from students in clinical placements. Rasch analysis was used to examine the construct validity of the APP tool in three different simulation assessment formats: longitudinal assessment over 1 week of simulation; longitudinal assessment over 2 weeks; and a short-form (25 min) assessment of a single simulation scenario. Comparison with APPs from 5 week clinical placements in hospital and clinic-based settings were also conducted. The APP demonstrated acceptable fit to the expectations of the Rasch model for the 1 and 2 week clinical simulations, exhibiting unidimensional properties that were able to distinguish different levels of student performance. For the short-form simulation, nine of the 20 items recorded greater than 25 % of scores as 'not-assessed' by clinical educators which impacted on the suitability of the APP tool in this simulation format. The APP was a valid assessment tool when used in longitudinal simulation formats. A revised APP may be required for assessment in short-form simulation scenarios.

Standard deviation of vertical two-point longitudinal velocity differences in the atmospheric boundary layer.

NASA Technical Reports Server (NTRS)

Fichtl, G. H.

1971-01-01

Statistical estimates of wind shear in the planetary boundary layer are important in the design of V/STOL aircraft, and for the design of the Space Shuttle. The data analyzed in this study consist of eleven sets of longitudinal turbulent velocity fluctuation time histories digitized at 0.2 sec intervals with approximately 18,000 data points per time history. The longitudinal velocity fluctuations were calculated with horizontal wind and direction data collected at the 18-, 30-, 60-, 90-, 120-, and 150-m levels. The data obtained confirm the result that Eulerian time spectra transformed to wave-number spectra with Taylor's frozen eddy hypothesis possess inertial-like behavior at wave-numbers well out of the inertial subrange.

Assisted Repeated Reading with an Advanced-Level Japanese EFL Reader: A Longitudinal Diary Study

ERIC Educational Resources Information Center

Taguchi, Etsuo; Gorsuch, Greta; Takayasu-Maass, Miyoko; Snipp, Kirsten

2012-01-01

Reading fluency has attracted the attention of reading researchers and educators since the early 1970s and has become a priority issue in English as a first language (L1) settings. It has also become a critical issue in English as a second or foreign language (L2) settings because the lack of fluency is considered a major obstacle to developing…

Longitudinal research and data collection in primary care.

PubMed

van Weel, Chris

2005-01-01

This article reviews examples of and experience with longitudinal research in family medicine. The objective is to use this empirical information to formulate recommendations for improving longitudinal research. The article discusses 3 longitudinal studies from the Nijmegen academic family practice research network: 1 on the prognosis of depression and 1 each on the prognosis of and outcomes of care for type 2 diabetes mellitus. The Nijmegen network has recorded all episodes of morbidity encountered in Dutch family medicine since 1971 in a stable practice population. This network's experience is evaluated to identify lessons that may help other practice-based research networks (PBRNs) in pursuing longitudinal research. In terms of external conditions (conditions related to the general setting), the stability of a population and a high level of continuity of care substantially enhance the ability to perform longitudinal research. In terms of internal conditions (conditions related to the PBRN), motivation of family physicians and their staff to conduct ongoing data collection, and their ownership of the data are key for success. Other critical internal conditions include standardization of data; collection of data by clinician-friendly means; training of family physicians and their staff in data collection, as well as meetings for discussion of this task; provision of feedback to practices on the research findings; use of standard procedures to promote adherence to data collection; availability of facilities for regular measurement of patients' health status or chart review; and use of mechanisms for tracking patients who leave the practice area. Insight from existing experience suggests that longitudinal research can be enhanced in PBRNs. The best way forward is to build longitudinal data collection by drawing on lessons from successful studies. Primary care research policy should advocate for a role of longitudinal research and stimulate its development in PBRNs under favorable population circumstances.

Exposing the Backstage: Critical Reflections on a Longitudinal Qualitative Study of Residents’ Care Networks in Assisted Living

PubMed Central

Kemp, Candace L.; Ball, Mary M.; Morgan, Jennifer Craft; Doyle, Patrick J.; Burgess, Elisabeth O.; Dillard, Joy A.; Barmon, Christina E.; Fitzroy, Andrea F.; Helmly, Victoria E.; Avent, Elizabeth S.; Perkins, Molly M.

2018-01-01

In this article, we analyze the research experiences associated with a longitudinal qualitative study of residents’ care networks in assisted living. Using data from researcher meetings, field notes, and memos, we critically examine our design and decision making and accompanying methodological implications. We focus on one complete wave of data collection involving 28 residents and 114 care network members in four diverse settings followed for 2 years. We identify study features that make our research innovative, but that also represent significant challenges. They include the focus and topic; settings and participants; scope and design complexity; nature, modes, frequency, and duration of data collection; and analytic approach. Each feature has methodological implications, including benefits and challenges pertaining to recruitment, retention, data collection, quality, and management, research team work, researcher roles, ethics, and dissemination. Our analysis demonstrates the value of our approach and of reflecting on and sharing methodological processes for cumulative knowledge building. PMID:27651072

Exposing the Backstage: Critical Reflections on a Longitudinal Qualitative Study of Residents' Care Networks in Assisted Living.

PubMed

Kemp, Candace L; Ball, Mary M; Morgan, Jennifer Craft; Doyle, Patrick J; Burgess, Elisabeth O; Dillard, Joy A; Barmon, Christina E; Fitzroy, Andrea F; Helmly, Victoria E; Avent, Elizabeth S; Perkins, Molly M

2017-07-01

In this article, we analyze the research experiences associated with a longitudinal qualitative study of residents' care networks in assisted living. Using data from researcher meetings, field notes, and memos, we critically examine our design and decision making and accompanying methodological implications. We focus on one complete wave of data collection involving 28 residents and 114 care network members in four diverse settings followed for 2 years. We identify study features that make our research innovative, but that also represent significant challenges. They include the focus and topic; settings and participants; scope and design complexity; nature, modes, frequency, and duration of data collection; and analytic approach. Each feature has methodological implications, including benefits and challenges pertaining to recruitment, retention, data collection, quality, and management, research team work, researcher roles, ethics, and dissemination. Our analysis demonstrates the value of our approach and of reflecting on and sharing methodological processes for cumulative knowledge building.

Advanced analytical methodologies for measuring healthy ageing and its determinants, using factor analysis and machine learning techniques: the ATHLOS project

PubMed Central

Félix Caballero, Francisco; Soulis, George; Engchuan, Worrawat; Sánchez-Niubó, Albert; Arndt, Holger; Ayuso-Mateos, José Luis; Haro, Josep Maria; Chatterji, Somnath; Panagiotakos, Demosthenes B.

2017-01-01

A most challenging task for scientists that are involved in the study of ageing is the development of a measure to quantify health status across populations and over time. In the present study, a Bayesian multilevel Item Response Theory approach is used to create a health score that can be compared across different waves in a longitudinal study, using anchor items and items that vary across waves. The same approach can be applied to compare health scores across different longitudinal studies, using items that vary across studies. Data from the English Longitudinal Study of Ageing (ELSA) are employed. Mixed-effects multilevel regression and Machine Learning methods were used to identify relationships between socio-demographics and the health score created. The metric of health was created for 17,886 subjects (54.6% of women) participating in at least one of the first six ELSA waves and correlated well with already known conditions that affect health. Future efforts will implement this approach in a harmonised data set comprising several longitudinal studies of ageing. This will enable valid comparisons between clinical and community dwelling populations and help to generate norms that could be useful in day-to-day clinical practice. PMID:28281663

Advanced analytical methodologies for measuring healthy ageing and its determinants, using factor analysis and machine learning techniques: the ATHLOS project.

PubMed

Caballero, Francisco Félix; Soulis, George; Engchuan, Worrawat; Sánchez-Niubó, Albert; Arndt, Holger; Ayuso-Mateos, José Luis; Haro, Josep Maria; Chatterji, Somnath; Panagiotakos, Demosthenes B

2017-03-10

A most challenging task for scientists that are involved in the study of ageing is the development of a measure to quantify health status across populations and over time. In the present study, a Bayesian multilevel Item Response Theory approach is used to create a health score that can be compared across different waves in a longitudinal study, using anchor items and items that vary across waves. The same approach can be applied to compare health scores across different longitudinal studies, using items that vary across studies. Data from the English Longitudinal Study of Ageing (ELSA) are employed. Mixed-effects multilevel regression and Machine Learning methods were used to identify relationships between socio-demographics and the health score created. The metric of health was created for 17,886 subjects (54.6% of women) participating in at least one of the first six ELSA waves and correlated well with already known conditions that affect health. Future efforts will implement this approach in a harmonised data set comprising several longitudinal studies of ageing. This will enable valid comparisons between clinical and community dwelling populations and help to generate norms that could be useful in day-to-day clinical practice.

Longitudinal Study on Fluency among Novice Learners of Japanese

ERIC Educational Resources Information Center

Hirotani, Maki; Matsumoto, Kazumi; Fukada, Atsusi

2012-01-01

The present study examined various aspects of the development of learners' fluency in Japanese using a large set of speech samples collected over a long period, using an online speaking practice/assessment system called "Speak Everywhere." The purpose of the present study was to examine: (1) how the fluency related measures changed over…

Getting in Touch with Paramedic Student Career Intentions

ERIC Educational Resources Information Center

O'Meara, Peter; Tourle, Vianne; Madigan, Veronica; Lighton, David

2012-01-01

Objective: This study of paramedic and nursing/paramedic students aimed to determine the initial career intentions of full-time paramedic students and to identify the key factors that influence their career choices. Design: A longitudinal study design, utilizing surveys and a focus group, was employed. Setting: The study was conducted in an…

Arguments at Mealtime and Child Energy Intake

ERIC Educational Resources Information Center

Burnier, Daniel; Dubois, Lise; Girard, Manon

2011-01-01

Objective: To examine how arguments at mealtimes relate to children's daily energy intake. Design: A cross-sectional study using data obtained through the Quebec Longitudinal Study of Child Development 1998-2010 (QLSCD), a representative sample of children born in 1998, in the province of Quebec, Canada. Setting: Face-to-face interviews,…

Can Neighbor Attributes Predict School Absences?

ERIC Educational Resources Information Center

Gottfried, Michael A.

2014-01-01

Recent evidence suggests that the neighborhood context, particularly for urban youth, can influence a range of outcomes. This study makes contributions to the field by examining how the neighborhood context directly relates to missing school. To do so, this study employs a large-scale, longitudinal data set of multilevel observations for entire…

Blended and Online Learning: Student Perceptions and Performance

ERIC Educational Resources Information Center

Adam, Stewart; Nel, Deon

2009-01-01

Purpose: The purpose of this paper is to improve educator knowledge of the antecedents and consequences of blended learning in higher education. Design/methodology/approach: A longitudinal case study approach is adopted. Three case studies each involve tracking a student evaluations of teaching (SET) measure (willingness to recommend) and grade…

Graduate Teacher Preparation for Rural Schools in Victoria and Queensland

ERIC Educational Resources Information Center

Kline, Jodie; Walker-Gibbs, Bernadette

2015-01-01

Graduate teachers' preparedness for working in rural settings are mediated by the development of pedagogical expertise, professional engagement with parents and the community, and broader notions of preparation to teach in rural contexts. The Studying the Effectiveness of Teacher Education (SETE) project is a four-year longitudinal study tracking…

Time-Course Gene Set Analysis for Longitudinal Gene Expression Data

PubMed Central

Hejblum, Boris P.; Skinner, Jason; Thiébaut, Rodolphe

2015-01-01

Gene set analysis methods, which consider predefined groups of genes in the analysis of genomic data, have been successfully applied for analyzing gene expression data in cross-sectional studies. The time-course gene set analysis (TcGSA) introduced here is an extension of gene set analysis to longitudinal data. The proposed method relies on random effects modeling with maximum likelihood estimates. It allows to use all available repeated measurements while dealing with unbalanced data due to missing at random (MAR) measurements. TcGSA is a hypothesis driven method that identifies a priori defined gene sets with significant expression variations over time, taking into account the potential heterogeneity of expression within gene sets. When biological conditions are compared, the method indicates if the time patterns of gene sets significantly differ according to these conditions. The interest of the method is illustrated by its application to two real life datasets: an HIV therapeutic vaccine trial (DALIA-1 trial), and data from a recent study on influenza and pneumococcal vaccines. In the DALIA-1 trial TcGSA revealed a significant change in gene expression over time within 69 gene sets during vaccination, while a standard univariate individual gene analysis corrected for multiple testing as well as a standard a Gene Set Enrichment Analysis (GSEA) for time series both failed to detect any significant pattern change over time. When applied to the second illustrative data set, TcGSA allowed the identification of 4 gene sets finally found to be linked with the influenza vaccine too although they were found to be associated to the pneumococcal vaccine only in previous analyses. In our simulation study TcGSA exhibits good statistical properties, and an increased power compared to other approaches for analyzing time-course expression patterns of gene sets. The method is made available for the community through an R package. PMID:26111374

The wage effects of obesity: a longitudinal study.

PubMed

Baum, Charles L; Ford, William F

2004-09-01

We use National Longitudinal Survey of Youth (NLSY) data to examine the effects of obesity on wages by gender. Sample means indicate that both men and women experience a persistent obesity wage penalty over the first two decades of their careers. We then control for a standard set of socioeconomic and familial variables but find that standard covariates do not explain why obese workers experience persistent wage penalties. This suggests that other variables -- including job discrimination, health-related factors and/or obese workers' behavior patterns -- may be the channels through which obesity adversely affects wages. The study closes with a discussion of the public policy implications suggested by these findings.

Systematic review of the association between physical activity and burnout.

PubMed

Naczenski, Lea M; Vries, Juriena D de; Hooff, Madelon L M van; Kompier, Michiel A J

2017-11-25

Burnout constitutes a health risk, and interventions are needed to reduce it. The aim of this study was to synthesize evidence regarding the relationship between physical activity and burnout by conducting a systematic review of longitudinal and intervention studies. A literature search resulted in the identification of a final set of ten studies: four longitudinal and six intervention studies. In separate analyses for each category, evidence was synthesized by extracting the study characteristics and assessing the methodological quality of each study. The strength of evidence was calculated with the standardized index of convergence (SIC). In longitudinal studies, we found moderately strong evidence (SIC (4) = -1) for a negative relationship between physical activity and the key component of burnout, i.e., exhaustion. We found strong evidence (SIC (6) = -0.86) for the effect of physical activity on reducing exhaustion in intervention studies. As only one study could be classified as a high quality study, these results of previous studies need to be interpreted with some caution. This systematic review suggests that physical activity constitutes an effective medium for the reduction of burnout. Although consistent evidence was found, there is a lack of high quality longitudinal and intervention studies considering the influence of physical activity on burnout. Therefore, future research should be conducted with the aim to produce high quality studies, to develop a full picture of physical activity as a strategy to reduce burnout.

Gender differences in the longitudinal structure of cognitive diatheses for depression in children and adolescents.

PubMed

Cole, David A; Jacquez, Farrah M; Truss, Alanna E; Pineda, Ashley Q; Weitlauf, Amy S; Tilghman-Osborne, Carlos E; Felton, Julia W; Maxwell, Melissa A

2009-12-01

In a school-based, four-wave, longitudinal study, children (grades 4-7) and young adolescents (grades 6-9) completed questionnaires measuring depressive symptoms and depressive cognitions, including positive and negative cognitions on the Cognitive Triad Inventory for Children (CTI-C; Kaslow, Stark, Printz, Livingston, & Tsai, 1992) and self-perceived competence on the Self-Perception Profile for Children (SPPC; Harter, 1985). Application of the Trait-State-Occasion model (Cole, Martin, & Steiger, 2005) revealed the existence of a time-invariant trait factor and a set of time-varying occasion factors. Gender differences emerged, indicating that some cognitive diatheses were more trait-like for girls than for boys (i.e., positive and negative cognitions on the CTI-C; self-perceived physical appearance and global self-worth on the SPPC). Implications focus on the emergent gender difference in depression, the design of longitudinal studies, and clinical decisions about the implementation of prevention versus intervention programs.

Childhood Precursors of Adult Borderline Personality Disorder Features: A Longitudinal Study.

PubMed

Cramer, Phebe

2016-07-01

This study identifies childhood personality traits that are precursors of adult Borderline Personality Disorder (BPD) features. In a longitudinal study, childhood personality traits were assessed at age 11 (N = 100) using the California Child Q-set (CCQ: Block and Block, 1980). A number of these Q-items were found to be significantly correlated (p < 0.001) with a prototype-based measure of BPD features at age 23. Factor analysis of these Q-items suggested that they could be characterized by two underlying personality dimensions: Impulsivity and Nonconformity/Aggression. The findings thus provide evidence that childhood personality traits predict adult BPD features. Identifying such childhood precursors provides an opportunity for early intervention.

Quantification of right ventricular volumes and function by real time three-dimensional echocardiographic longitudinal axial plane method: validation in the clinical setting.

PubMed

Endo, Yuka; Maddukuri, Prasad V; Vieira, Marcelo L C; Pandian, Natesa G; Patel, Ayan R

2006-11-01

Measurement of right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) by three-dimensional echocardiographic (3DE) short-axis disc summation method has been validated in multiple studies. However, in some patients, short-axis images are of insufficient quality for accurate tracing of the RV endocardial border. This study examined the accuracy of long-axis analysis in multiple planes (longitudinal axial plane method) for assessment of RV volumes and RVEF. 3DE images were analyzed in 40 subjects with a broad range of RV function. RV end-diastolic (RVEDV) and end-systolic volumes (RVESV) and RVEF were calculated by both short-axis disc summation method and longitudinal axial plane method. Excellent correlation was obtained between the two methods for RVEDV, RVESV, and RVEF (r = 0.99, 0.99, 0.94, respectively; P < 0.0001 for all comparisons). 3DE longitudinal-axis analysis is a promising technique for the evaluation of RV function, and may provide an alternative method of assessment in patients with suboptimal short-axis images.

A Sociocultural Perspective on Young Deaf Children's Fingerspelling: An Ethnographic Study in a Signing Setting

ERIC Educational Resources Information Center

Roos, Carin

2014-01-01

This study, which is part of a larger longitudinal ethnographic study of young deaf children, reports on deaf children's use of fingerspelling. The children observed were early signers using Swedish Sign Language (SSL) in communication with teachers and peers. This study centres on the functions of fingerspelling in the children's everyday…

An ``Openable,'' High-Strength Gradient Set for Orthopedic MRI

NASA Astrophysics Data System (ADS)

Crozier, Stuart; Roffmann, Wolfgang U.; Luescher, Kurt; Snape-Jenkinson, Christopher; Forbes, Lawrence K.; Doddrell, David M.

1999-07-01

A novel three-axis gradient set and RF resonator for orthopedic MRI has been designed and constructed. The set is openable and may be wrapped around injured joints. The design methodology used was the minimization of magnetic field spherical harmonics by simulated annealing. Splitting of the longitudinal coil presents the major design challenge to a fully openable gradient set and in order to efficiently design such coils, we have developed a new fast algorithm for determining the magnetic field spherical harmonics generated by an arc of multiturn wire. The algorithm allows a realistic impression of the effect of split longitudinal designs. A prototype set was constructed based on the new designs and tested in a 2-T clinical research system. The set generated 12 mT/m/A with a linear region of 12 cm and a switching time of 100 μs, conforming closely with theoretical predictions. Preliminary images from the set are presented.

Structure and Correlates of Cognitive Aging in a Narrow Age Cohort

PubMed Central

2014-01-01

Aging-related changes occur for multiple domains of cognitive functioning. An accumulating body of research indicates that, rather than representing statistically independent phenomena, aging-related cognitive changes are moderately to strongly correlated across domains. However, previous studies have typically been conducted in age-heterogeneous samples over longitudinal time lags of 6 or more years, and have failed to consider whether results are robust to a comprehensive set of controls. Capitalizing on 3-year longitudinal data from the Lothian Birth Cohort of 1936, we took a longitudinal narrow age cohort approach to examine cross-domain cognitive change interrelations from ages 70 to 73 years. We fit multivariate latent difference score models to factors representing visuospatial ability, processing speed, memory, and crystallized ability. Changes were moderately interrelated, with a general factor of change accounting for 47% of the variance in changes across domains. Change interrelations persisted at close to full strength after controlling for a comprehensive set of demographic, physical, and medical factors including educational attainment, childhood intelligence, physical function, APOE genotype, smoking status, diagnosis of hypertension, diagnosis of cardiovascular disease, and diagnosis of diabetes. Thus, the positive manifold of aging-related cognitive changes is highly robust in that it can be detected in a narrow age cohort followed over a relatively brief longitudinal period, and persists even after controlling for many potential confounders. PMID:24955992

Structure and correlates of cognitive aging in a narrow age cohort.

PubMed

Tucker-Drob, Elliot M; Briley, Daniel A; Starr, John M; Deary, Ian J

2014-06-01

Aging-related changes occur for multiple domains of cognitive functioning. An accumulating body of research indicates that, rather than representing statistically independent phenomena, aging-related cognitive changes are moderately to strongly correlated across domains. However, previous studies have typically been conducted in age-heterogeneous samples over longitudinal time lags of 6 or more years, and have failed to consider whether results are robust to a comprehensive set of controls. Capitalizing on 3-year longitudinal data from the Lothian Birth Cohort of 1936, we took a longitudinal narrow age cohort approach to examine cross-domain cognitive change interrelations from ages 70 to 73 years. We fit multivariate latent difference score models to factors representing visuospatial ability, processing speed, memory, and crystallized ability. Changes were moderately interrelated, with a general factor of change accounting for 47% of the variance in changes across domains. Change interrelations persisted at close to full strength after controlling for a comprehensive set of demographic, physical, and medical factors including educational attainment, childhood intelligence, physical function, APOE genotype, smoking status, diagnosis of hypertension, diagnosis of cardiovascular disease, and diagnosis of diabetes. Thus, the positive manifold of aging-related cognitive changes is highly robust in that it can be detected in a narrow age cohort followed over a relatively brief longitudinal period, and persists even after controlling for many potential confounders. PsycINFO Database Record (c) 2014 APA, all rights reserved.

The ROOTS study: a 10-year review of findings on adolescent depression, and recommendations for future longitudinal research.

PubMed

Lewis, Gemma; Jones, Peter B; Goodyer, Ian M

2016-02-01

The purpose of this study is to review longitudinal findings on adolescent mental health from the 'ROOTS study', and provide directions and recommendations for future longitudinal research. To do this, we discuss relevant findings from the ROOTS study, and review its strengths and limitations. We examined all publications from the ROOTS study up to July 2015, selected those examining adolescent mental health, and classified them as investigating (a) childhood risk factors for adolescent depression, (b) genetic and cognitive vulnerability to depression in adolescence, (c) genetic markers, childhood adversities, and neuroendophenotypes, (d) morning cortisol and depression, (e) physical activity and depression symptoms, and (f) the underlying structure of mental health in adolescence. We reviewed the strengths and limitations of the ROOTS study, and how they feed into recommendations for future longitudinal research. There was evidence supporting a putative hormonal biomarker for the emergence of depression in boys. Environmental pathways from child adversity to adolescent depression were confirmed in girls, partly accounted for by negative life events in early adolescence. The preceding role of automatic cognitive biases assessed using behavioural tasks was substantiated, with evidence for genetic susceptibility. Novel latent statistical models of child adversity, depression, anxiety, and psychotic experiences were produced, with concurrent and prospective validity. Our experiences conducting the ROOTS study resulted in a set of strengths, limitations, and recommendations for future longitudinal studies. The ROOTS study has advanced knowledge on the aetiology of adolescent depression by investigating environmental, genetic, hormonal, and neural risk factors. Findings provide a foundation for future research integrating cognitive neuroscience with epidemiology.

Causal mediation analysis for longitudinal data with exogenous exposure.

PubMed

Bind, M-A C; Vanderweele, T J; Coull, B A; Schwartz, J D

2016-01-01

Mediation analysis is a valuable approach to examine pathways in epidemiological research. Prospective cohort studies are often conducted to study biological mechanisms and often collect longitudinal measurements on each participant. Mediation formulae for longitudinal data have been developed. Here, we formalize the natural direct and indirect effects using a causal framework with potential outcomes that allows for an interaction between the exposure and the mediator. To allow different types of longitudinal measures of the mediator and outcome, we assume two generalized mixed-effects models for both the mediator and the outcome. The model for the mediator has subject-specific random intercepts and random exposure slopes for each cluster, and the outcome model has random intercepts and random slopes for the exposure, the mediator, and their interaction. We also expand our approach to settings with multiple mediators and derive the mediated effects, jointly through all mediators. Our method requires the absence of time-varying confounding with respect to the exposure and the mediator. This assumption is achieved in settings with exogenous exposure and mediator, especially when exposure and mediator are not affected by variables measured at earlier time points. We apply the methodology to data from the Normative Aging Study and estimate the direct and indirect effects, via DNA methylation, of air pollution, and temperature on intercellular adhesion molecule 1 (ICAM-1) protein levels. Our results suggest that air pollution and temperature have a direct effect on ICAM-1 protein levels (i.e. not through a change in ICAM-1 DNA methylation) and that temperature has an indirect effect via a change in ICAM-1 DNA methylation. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Subjective and Objective Parameters Determining "Salience" in Long-Term Dialect Accommodation.

ERIC Educational Resources Information Center

Auer, Peter; Barden, Birgit; Grosskopf, Beate

1998-01-01

Presents results of a longitudinal study on long-term dialect accommodation in a German dialect setting. An important model of explaining which linguistic structures undergo such convergence and which do not makes use of the notion of "salience." (Author/VWL)

Estimating onset time from longitudinal and cross-sectional data with an application to estimating gestational age from longitudinal maternal anthropometry during pregnancy and neonatal anthropometry at birth.

PubMed

Ortega-Villa, Ana Maria; Grantz, Katherine L; Albert, Paul S

2018-06-01

Determining the date of conception is important for estimating gestational age and monitoring whether the fetus and mother are on track in their development and pregnancy. Various methods based on ultrasound have been proposed for dating a pregnancy in high resource countries. However, such techniques may not be available in under-resourced countries. We develop a shared random parameter model for estimating the date of conception using longitudinal assessment of multiple maternal anthropometry and cross-sectional neonatal anthropometry. The methodology is evaluated with a training-test set paradigm as well as with simulations to examine the robustness of the method to model misspecification. We illustrate this new methodology with data from the NICHD Fetal Growth Studies.

Can a Simple Dietary Index Derived from a Sub-Set of Questionnaire Items Assess Diet Quality in a Sample of Australian Adults?

PubMed Central

Trapp, Georgina S. A.; Knuiman, Matthew; Hooper, Paula; Ambrosini, Gina L.

2018-01-01

Large, longitudinal surveys often lack consistent dietary data, limiting the use of existing tools and methods that are available to measure diet quality. This study describes a method that was used to develop a simple index for ranking individuals according to their diet quality in a longitudinal study. The RESIDential Environments (RESIDE) project (2004–2011) collected dietary data in varying detail, across four time points. The most detailed dietary data were collected using a 24-item questionnaire at the final time point (n = 555; age ≥ 25 years). At preceding time points, sub-sets of the 24 items were collected. A RESIDE dietary guideline index (RDGI) that was based on the 24-items was developed to assess diet quality in relation to the Australian Dietary Guidelines. The RDGI scores were regressed on the longitudinal sub-sets of six and nine questionnaire items at T4, from which two simple index scores (S-RDGI1 and S-RDGI2) were predicted. The S-RDGI1 and S-RDGI2 showed reasonable agreement with the RDGI (Spearman’s rho = 0.78 and 0.84; gross misclassification = 1.8%; correct classification = 64.9% and 69.7%; and, Cohen’s weighted kappa = 0.58 and 0.64, respectively). For all of the indices, higher diet quality was associated with being female, undertaking moderate to high amounts of physical activity, not smoking, and self-reported health. The S-RDGI1 and S-RDGI2 explained 62% and 73% of the variation in RDGI scores, demonstrating that a large proportion of the variability in diet quality scores can be captured using a relatively small sub-set of questionnaire items. The methods described in this study can be applied elsewhere, in situations where limited dietary data are available, to generate a sample-specific score for ranking individuals according to diet quality. PMID:29652828

Can a Simple Dietary Index Derived from a Sub-Set of Questionnaire Items Assess Diet Quality in a Sample of Australian Adults?

PubMed

Bivoltsis, Alexia; Trapp, Georgina S A; Knuiman, Matthew; Hooper, Paula; Ambrosini, Gina L

2018-04-13

Large, longitudinal surveys often lack consistent dietary data, limiting the use of existing tools and methods that are available to measure diet quality. This study describes a method that was used to develop a simple index for ranking individuals according to their diet quality in a longitudinal study. The RESIDential Environments (RESIDE) project (2004-2011) collected dietary data in varying detail, across four time points. The most detailed dietary data were collected using a 24-item questionnaire at the final time point ( n = 555; age ≥ 25 years). At preceding time points, sub-sets of the 24 items were collected. A RESIDE dietary guideline index (RDGI) that was based on the 24-items was developed to assess diet quality in relation to the Australian Dietary Guidelines. The RDGI scores were regressed on the longitudinal sub-sets of six and nine questionnaire items at T4, from which two simple index scores (S-RDGI1 and S-RDGI2) were predicted. The S-RDGI1 and S-RDGI2 showed reasonable agreement with the RDGI (Spearman's rho = 0.78 and 0.84; gross misclassification = 1.8%; correct classification = 64.9% and 69.7%; and, Cohen's weighted kappa = 0.58 and 0.64, respectively). For all of the indices, higher diet quality was associated with being female, undertaking moderate to high amounts of physical activity, not smoking, and self-reported health. The S-RDGI1 and S-RDGI2 explained 62% and 73% of the variation in RDGI scores, demonstrating that a large proportion of the variability in diet quality scores can be captured using a relatively small sub-set of questionnaire items. The methods described in this study can be applied elsewhere, in situations where limited dietary data are available, to generate a sample-specific score for ranking individuals according to diet quality.

Definition and application of longitudinal stability derivatives for elastic airplanes

NASA Technical Reports Server (NTRS)

Kemp, W. B., Jr.

1972-01-01

A set of longitudinal stability derivatives for elastic airplanes is defined from fundamental principles allowing perturbations in forward speed. Application of these derivatives to longitudinal stability analysis by use of approximate expressions for static stability and control parameters as well as the dynamic equations of motion is illustrated. One commonly used alternative formulation for elastic airplanes is shown to yield significant inaccuracies because of inappropriate interpretation of inertial effects.

Brand name or generic? What are the health professionals prescribed for treating diabetes? A longitudinal analysis of the National Health Insurance reimbursement database.

PubMed

Liou, Wen-Shyong; Hsieh, Shu-Ching; Chang, Wai-Yuan; Wu, Grace Hui-Min; Huang, Hsu-Shan; Lee, Chuanfang

2013-07-01

This study aimed to explore whether physicians prescribe more brand-name oral hypoglycemic agents (OHA) for diabetic patients with medical training background (MP) than for general patients (GP). A longitudinal analysis of 1,000,000 National Health Insurance cohorts of 1998-2008 was conducted. Univariate and multivariate models were performed to assess the associations of the outcome (the ratio of brand-name/generic odds in the MP group to that in the GP group) and the covariates, including patient medical training background, characteristics of patient, prescriber, and medical settings, and market competition. A generalized estimating equation method was used to control the dependency of longitudinal data. A total of 46,850 diabetic patients were prescribed with 2,703,149 OHA prescriptions during the study period. Compared with GP, MP had 1.37 times greater odds of being prescribed with brand-name instead of generic OHA, among whom pharmacists and physicians had the highest odds ratios of 2.78 (95%CI, 1.05-7.36) and 1.68 (95%CI, 0.99-2.85), respectively. Patients' diabetes severity, prescribers' level of experience, medical settings that were publicly owned, had a higher accreditation level, and were located in a higher urbanized area, lower market competition, and earlier dates of prescription were positively associated with brand-name prescription. Among all medical sub-specialties, cardiologists were more likely to prescribe brand-name OHA. This study is the first to demonstrate how a patients' medical training background, in addition to the characteristics of patients, prescribers, and medical settings, and market competition might influence physicians' prescribing choice of brand-name or generic OHA. Copyright © 2013 John Wiley & Sons, Ltd.

A multisample study of longitudinal changes in brain network architecture in 4-13-year-old children.

PubMed

Wierenga, Lara M; van den Heuvel, Martijn P; Oranje, Bob; Giedd, Jay N; Durston, Sarah; Peper, Jiska S; Brown, Timothy T; Crone, Eveline A

2018-01-01

Recent advances in human neuroimaging research have revealed that white-matter connectivity can be described in terms of an integrated network, which is the basis of the human connectome. However, the developmental changes of this connectome in childhood are not well understood. This study made use of two independent longitudinal diffusion-weighted imaging data sets to characterize developmental changes in the connectome by estimating age-related changes in fractional anisotropy (FA) for reconstructed fibers (edges) between 68 cortical regions. The first sample included 237 diffusion-weighted scans of 146 typically developing children (4-13 years old, 74 females) derived from the Pediatric Longitudinal Imaging, Neurocognition, and Genetics (PLING) study. The second sample included 141 scans of 97 individuals (8-13 years old, 62 females) derived from the BrainTime project. In both data sets, we compared edges that had the most substantial age-related change in FA to edges that showed little change in FA. This allowed us to investigate if developmental changes in white matter reorganize network topology. We observed substantial increases in edges connecting peripheral and a set of highly connected hub regions, referred to as the rich club. Together with the observed topological differences between regions connecting to edges showing the smallest and largest changes in FA, this indicates that changes in white matter affect network organization, such that highly connected regions become even more strongly imbedded in the network. These findings suggest that an important process in brain development involves organizing patterns of inter-regional interactions. Hum Brain Mapp 39:157-170, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Ethnic Variations of Pathways Linking Socioeconomic Status, Parenting, and Preacademic Skills in a Nationally Representative Sample

ERIC Educational Resources Information Center

Iruka, Iheoma U.; Dotterer, Aryn M.; Pungello, Elizabeth P.

2014-01-01

Research Findings: Grounded in the investment model and informed by the integrative theory of the study of minority children, this study used the Early Childhood Longitudinal Study-Birth Cohort data set, a nationally representative sample of young children, to investigate whether the association between socioeconomic status (family income and…

Using Mixed Methods to Study First-Year College Impact on Liberal Arts Learning Outcomes

ERIC Educational Resources Information Center

Seifert, Tricia A.; Goodman, Kathleen; King, Patricia M.; Baxter Magolda, Marcia B.

2010-01-01

This study details the collection, analysis, and interpretation of data from a national multi-institutional longitudinal mixed methods study of college impact and student development of liberal arts outcomes. The authors found three sets of practices in the quantitative data that corroborated with the themes that emerged from the qualitative data:…

The impact of nutritional status and longitudinal recovery of motor and cognitive milestones in internationally adopted children.

PubMed

Park, Hyun; Bothe, Denise; Holsinger, Eva; Kirchner, H Lester; Olness, Karen; Mandalakas, Anna

2011-01-01

Internationally adopted children often arrive from institutional settings where they have experienced medical, nutritional and psychosocial deprivation. This study uses a validated research assessment tool to prospectively assess the impact of baseline (immediately post adoption) nutritional status on fifty-eight children as measured by weight-for-age, height-for-age, weight-for-height and head circumference-for-age z scores, as a determinant of cognitive (MDI) and psychomotor development (PDI) scores longitudinally. A statistical model was developed to allow for different ages at time of initial assessment as well as variable intervals between follow up visits. The study results show that both acute and chronic measures of malnutrition significantly affect baseline developmental status as well as the rate of improvement in both MDI and PDI scores. This study contributes to the body of literature with its prospective nature, unique statistical model for longitudinal evaluation, and use of a validated assessment tool to assess outcomes.

Cross-sectional and longitudinal epidemiological studies of Internet gaming disorder: A systematic review of the literature.

PubMed

Mihara, Satoko; Higuchi, Susumu

2017-07-01

The diagnostic criteria of Internet gaming disorder (IGD) have been included in section III of DSM-5. This study aims to systematically review both cross-sectional and longitudinal epidemiological studies of IGD. All publications included in PubMed and PsychINFO up to May 2016 were systematically searched to identify cross-sectional studies on prevalence and longitudinal studies of IGD. In the process of identification, articles in non-English languages and studies focusing solely on the use of gaming were excluded, and those meeting the methodological requirements set by this review were included. As a result, 37 cross-sectional and 13 longitudinal studies were selected for review. The prevalence of IGD in the total samples ranged from 0.7% to 27.5%. The prevalence was higher among males than females in the vast majority of studies and tended to be higher among younger rather than older people in some studies. Geographical region made little difference to prevalence. Factors associated with IGD were reported in 28 of 37 cross-sectional studies. These were diverse and covered gaming, demographic and familial factors, interpersonal relations, social and school functioning, personality, psychiatric comorbidity, and physical health conditions. Longitudinal studies identified risk and protective factors, and health and social consequences of IGD. The natural course of IGD was diverse but tended to be more stable among adolescents compared to adults. Although existing epidemiological studies have provided useful data, differences in methodologies make it difficult to compare the findings of these studies when drawing consensus. Future international studies using reliable and uniform methods are warranted. © 2017 The Authors. Psychiatry and Clinical Neurosciences © 2017 Japanese Society of Psychiatry and Neurology.

The Development of Information Search Expertise of Research Students

ERIC Educational Resources Information Center

Kai-Wah Chu, Samuel; Law, Nancy

2008-01-01

This study identifies the development of information search expertise of 12 beginning research students (six in education and six in engineering) who were provided with a set of systematic search training sessions over a period of one year. The study adopts a longitudinal approach in investigating whether there were different stages in the…

Acculturation Process and Distress: Mediating Roles of Sociocultural Adaptation and Acculturative Stress

ERIC Educational Resources Information Center

Wu, Ellery K. Y.; Mak, Winnie W. S.

2012-01-01

The present study applied the theory of planned behavior (TPB) to unfold the social cognitive antecedents of acculturation and investigated the effects of acculturation on psychological distress using a longitudinal design. A total of 180 mainland Chinese university students studying in Hong Kong completed three sets of questionnaires every 2…

Data Sharing and Reuse within the Academic Pathways Study

ERIC Educational Resources Information Center

Toye, George; Sheppard, Sheri; Chen, Helen L.

2016-01-01

The Academic Pathway Study (APS) research program within National Science Foundation (NSF) Center for Advancement of Engineering Education (CAEE) ran from 2003-2010. It amassed a collection of longitudinal as well as cross-sectional data sets, of varying research method types and formats, from four different primary cohorts that included over…

Diagnosis of Autism Spectrum Disorders in 2-Year-Olds: A Study of Community Practice

ERIC Educational Resources Information Center

Corsello, Christina M.; Akshoomoff, Natacha; Stahmer, Aubyn C.

2013-01-01

Background: Longitudinal research studies have demonstrated that experienced clinicians using standardized assessment measures can make a reliable diagnosis of autism spectrum disorders (ASDs) in children under age 3. Limited data are available regarding the sensitivity and specificity of these measures in community settings. The aims of this…

Postschool Goals and Transition Services for Students with Learning Disabilities

ERIC Educational Resources Information Center

Daviso, Alfred W.; Denney, Stephen C.; Baer, Robert M.; Flexer, Robert

2011-01-01

This article describes the initial findings for students with learning disabilities from the first year of The Ohio Longitudinal Transition Study (OLTS). The study included 416 participants with learning disabilities who were exiting high school. Data from an in-school survey were analyzed by sample demographics (e.g. school setting, school type,…

Discourse-Level Reading Comprehension in Chinese Children: What Is the Role of Syntactic Awareness?

ERIC Educational Resources Information Center

Tong, Xiuhong; Tong, Xiuli; Shu, Hua; Chan, Shingfong; McBride-Chang, Catherine

2014-01-01

This study aimed to investigate the association between syntactic awareness and discourse-level reading comprehension in 136 Hong Kong Chinese children. These children, aged 11, from a longitudinal study, were administered a set of cognitive and linguistic measures. Partial correlational analyses showed that children's performances in two…

The Consequences of Ignoring Individuals' Mobility in Multilevel Growth Models: A Monte Carlo Study

ERIC Educational Resources Information Center

Luo, Wen; Kwok, Oi-man

2012-01-01

In longitudinal multilevel studies, especially in educational settings, it is fairly common that participants change their group memberships over time (e.g., students switch to different schools). Participant's mobility changes the multilevel data structure from a purely hierarchical structure with repeated measures nested within individuals and…

Achievement Orientations, School Adjustment, and Well-Being: A Longitudinal Study

ERIC Educational Resources Information Center

Maatta, Sami; Nurmi, Jari-Erik; Stattin, Hakan

2007-01-01

This study set out to identify the kinds of achievement orientations that adolescents show, and to examine the kinds of antecedents and consequences the use of a particular orientation has. The participants were 734 Swedish adolescents (335 boys and 399 girls) who filled in questionnaires measuring their achievement beliefs and behaviors,…

Researchers Supporting Schools to Improve Health: Influential Factors and Outcomes of Knowledge Brokering in the COMPASS Study

ERIC Educational Resources Information Center

Brown, Kristin M.; Elliott, Susan J.; Leatherdale, Scott T.

2018-01-01

Background: Although schools are considered opportune settings for youth health interventions, a gap between school health research and practice exists. COMPASS, a longitudinal study of Ontario and Alberta secondary students and schools (2012-2021), used integrated knowledge translation to enhance schools' uptake of research findings. Schools…

Nutrition Beliefs of Disadvantaged Parents of Overweight Children

ERIC Educational Resources Information Center

Pescud, Melanie; Pettigrew, Simone; Henley, Nadine

2014-01-01

Objective: To explore low socioeconomic parents' beliefs in relation to children's nutrition. Design: A qualitative, longitudinal study over 12 months involving 37 low socioeconomic parents. Setting: Perth, Western Australia. Method: Parents' nutrition-related beliefs were explored via interviews, focus groups and…

Factor Structure of the Piagetian Stage of Concrete Operations.

ERIC Educational Resources Information Center

Klausmeier, Herbert J.; Sipple, Thomas S.

1982-01-01

The Piagetian developmental stage of concrete operational thought and the theoretical groupement structures underlying children's performance of 12 concrete operations tasks are discussed. Tasks were shown to develop in five related sets. Three factor structures were found in this longitudinal study. (Author/CM)

Patient Core Data Set. Standard for a longitudinal health/medical record.

PubMed

Renner, A L; Swart, J C

1997-01-01

Blue Chip Computers Company, in collaboration with Wright State University-Miami Valley College of Nursing and Health, with support from the Agency for Health Care Policy and Research, Public Health Service, completed Small Business innovative Research research to design a comprehensive integrated Patient information System. The Wright State University consultants undertook the development of a Patient Core Data Set (PCDS) in response to the lack of uniform standards of minimum data sets, and lack of standards in data transfer for continuity of care. The purpose of the Patient Core Data Set is to develop a longitudinal patient health record and medical history using a common set of standard data elements with uniform definitions and coding consistent with Health Level 7 (HL7) protocol and the American Society for Testing and Materials (ASTM) standards. The PCDS, intended for transfer across all patient-care settings, is essential information for clinicians, administrators, researchers, and health policy makers.

Facilitating Development Research: Suggestions for Recruiting and Re-Recruiting Children and Families

PubMed Central

Hurwitz, Lisa B.; Schmitt, Kelly L.; Olsen, Megan K.

2017-01-01

Recruiting children and families for research studies can be challenging, and re-recruiting former participants for longitudinal research can be even more difficult, especially when a study was not prospectively designed to encompass continuous data collection. In this article, we explain how researchers can set up initial studies to potentially facilitate later waves of data collection; locate former study participants using newer, often digital, tools; schedule families using recruitment phone/email/mail scripts that highlight the many benefits to continued study participation; and confirm appointments with other digital tools. We draw from prior methodological and longitudinal pieces to provide suggestions to others wishing to re-recruit families for longitudinal studies. In addition, we draw upon our own experience conducting a non-prospective longitudinal study 6 years after an educational intervention, in which we successfully re-located 122 (90%) and interviewed 101 of 136 (83% of the located sample and 74% of the full original sample) parents and their early adolescent children. Although the majority of participants were recruited via original contact information (especially phone numbers), using a range of strategies to recruit (e.g., search engines focused on contact information, social media) and motivate participation (e.g., multifaceted phone/email/mail scheduling scripts, flexibility in location and means of participation) yielded a more desirable sample size at relatively low costs. PMID:28955265

Social Learning in a Longitudinal Integrated Clinical Placement

ERIC Educational Resources Information Center

Roberts, Chris; Daly, Michele; Held, Fabian; Lyle, David

2017-01-01

Recent research has demonstrated that longitudinal integrated placements (LICs) are an alternative mode of clinical education to traditional placements. Extended student engagement in community settings provide the advantages of educational continuity as well as increased service provision in underserved areas. Developing and maintaining LICs…

Predicting longitudinal trajectories of health probabilities with random-effects multinomial logit regression.

PubMed

Liu, Xian; Engel, Charles C

2012-12-20

Researchers often encounter longitudinal health data characterized with three or more ordinal or nominal categories. Random-effects multinomial logit models are generally applied to account for potential lack of independence inherent in such clustered data. When parameter estimates are used to describe longitudinal processes, however, random effects, both between and within individuals, need to be retransformed for correctly predicting outcome probabilities. This study attempts to go beyond existing work by developing a retransformation method that derives longitudinal growth trajectories of unbiased health probabilities. We estimated variances of the predicted probabilities by using the delta method. Additionally, we transformed the covariates' regression coefficients on the multinomial logit function, not substantively meaningful, to the conditional effects on the predicted probabilities. The empirical illustration uses the longitudinal data from the Asset and Health Dynamics among the Oldest Old. Our analysis compared three sets of the predicted probabilities of three health states at six time points, obtained from, respectively, the retransformation method, the best linear unbiased prediction, and the fixed-effects approach. The results demonstrate that neglect of retransforming random errors in the random-effects multinomial logit model results in severely biased longitudinal trajectories of health probabilities as well as overestimated effects of covariates on the probabilities. Copyright © 2012 John Wiley & Sons, Ltd.

Systematic review of the association between physical activity and burnout

PubMed Central

Naczenski, Lea M.; de Vries, Juriena D.; van Hooff, Madelon L. M.; Kompier, Michiel A. J.

2017-01-01

Objective: Burnout constitutes a health risk, and interventions are needed to reduce it. The aim of this study was to synthesize evidence regarding the relationship between physical activity and burnout by conducting a systematic review of longitudinal and intervention studies. Methods: A literature search resulted in the identification of a final set of ten studies: four longitudinal and six intervention studies. In separate analyses for each category, evidence was synthesized by extracting the study characteristics and assessing the methodological quality of each study. The strength of evidence was calculated with the standardized index of convergence (SIC). Results: In longitudinal studies, we found moderately strong evidence (SIC (4) = -1) for a negative relationship between physical activity and the key component of burnout, i.e., exhaustion. We found strong evidence (SIC (6) = -0.86) for the effect of physical activity on reducing exhaustion in intervention studies. As only one study could be classified as a high quality study, these results of previous studies need to be interpreted with some caution. Conclusions: This systematic review suggests that physical activity constitutes an effective medium for the reduction of burnout. Although consistent evidence was found, there is a lack of high quality longitudinal and intervention studies considering the influence of physical activity on burnout. Therefore, future research should be conducted with the aim to produce high quality studies, to develop a full picture of physical activity as a strategy to reduce burnout. PMID:28993574

Multiple imputation as one tool to provide longitudinal databases for modelling human height and weight development.

PubMed

Aßmann, C

2016-06-01

Besides large efforts regarding field work, provision of valid databases requires statistical and informational infrastructure to enable long-term access to longitudinal data sets on height, weight and related issues. To foster use of longitudinal data sets within the scientific community, provision of valid databases has to address data-protection regulations. It is, therefore, of major importance to hinder identifiability of individuals from publicly available databases. To reach this goal, one possible strategy is to provide a synthetic database to the public allowing for pretesting strategies for data analysis. The synthetic databases can be established using multiple imputation tools. Given the approval of the strategy, verification is based on the original data. Multiple imputation by chained equations is illustrated to facilitate provision of synthetic databases as it allows for capturing a wide range of statistical interdependencies. Also missing values, typically occurring within longitudinal databases for reasons of item non-response, can be addressed via multiple imputation when providing databases. The provision of synthetic databases using multiple imputation techniques is one possible strategy to ensure data protection, increase visibility of longitudinal databases and enhance the analytical potential.

Recent Developments in Social Science Research

ERIC Educational Resources Information Center

Jenness, David

1978-01-01

In this discussion of recent theoretical and methodological developments in three selected areas of the social sciences--social indicators, social experimentation and evaluation, and longitudinal studies, attention is given to the growing availability of machine-readable data sets and to special archives and resources of interest to librarians.…

Measuring Narcissism within Add Health: The Development and Validation of a New Scale

ERIC Educational Resources Information Center

Davis, Mark S.; Brunell, Amy B.

2012-01-01

This study reports the development of a measure of narcissism within the National Longitudinal Study of Adolescent Health (Add Health) data set. In Study 1, items were selected from Wave III to form the Add Health Narcissism Scale (AHNS). These were factor analyzed, yielding a single factor comprised of five subscales. We correlated the AHNS and…

Is It the Music or Is It Selection Bias? A Nationwide Analysis of Music and Non-Music Students' SAT Scores

ERIC Educational Resources Information Center

Elpus, Kenneth

2013-01-01

This study examined the college entrance examination scores of music and non-music students in the United States, drawing data from the restricted-use data set of the Education Longitudinal Study of 2002 (ELS), a nationally representative education study ("N" = 15,630) conducted by the National Center for Education Statistics. Analyses…

The Avid Adolescent Reader Revisited: Gender Differences and Their Association with Family Factors

ERIC Educational Resources Information Center

Chen, Su-Yen; Lu, Luo

2012-01-01

As a follow-up study to a cross-sectional national study that established the linkage between gender as well as family factors and the likelihood of being Taiwanese adolescent readers, this study attempted to utilize the same data set with longitudinal data to explore whether the association between family factors and being an avid adolescent…

Longitudinal posturography and rotational testing in children 3-9 years of age: Normative data

PubMed Central

Casselbrant, Margaretha L.; Mandel, Ellen M.; Sparto, Patrick J; Perera, Subashan; Redfern, Mark S.; Fall, Patricia A.; Furman, Joseph M.

2010-01-01

Objective To obtain normative longitudinal vestibulo-ocular and balance test data in children from ages 3 to 9 with normal middle-ear status. Study Design Prospective, longitudinal cohort Setting Tertiary care pediatric hospital Subjects and Methods Three-year-old children were entered and tested yearly. Subjects underwent earth vertical axis rotation testing using sinusoidal and constant velocity stimuli and performed the Sensory Organization Test. Results One hundred forty-eight children were entered and usable data were collected on 127 children. A linear increase in the vestibulo-ocular reflex gain as children aged was found, without a change in the phase of the response. An age-related linear increase in Equilibrium Scores, indicating reduced postural sway, was also observed. Conclusion These normative data can be used in the evaluation of dizziness and balance disorders in children. PMID:20416461

Earning and Learning: The Impact of Paid Work on First-Generation Student Persistence

ERIC Educational Resources Information Center

Micka-Pickunka, Marilyn

2010-01-01

This study utilized the Beginning Postsecondary Student (BPS) longitudinal data set (2004-2006) from the National Center for Educational Statistics (NCES), which will follow for six academic years a nationally representative sample of students who began their postsecondary education during the 2004-2005 academic year. The purpose of this study is…

The Longitudinal Development of Oral Linguistic Complexity and Accuracy of Spanish Learner Language in Second-Year University Students

ERIC Educational Resources Information Center

Bajuniemi, Abby Louise

2015-01-01

To date, few studies have investigated the production of linguistic complexity and accuracy with naturalistic data. Very often, the data are obtained in a laboratory or laboratory-style settings, with tasks defined by the researcher rather than the instructor (Hatch, 1978; Seedhouse, 2004). Additionally, replicability of studies that investigate…

Variance of Student Achievement in Effective and Ineffective Schools: Inconsistencies across SES Categories.

ERIC Educational Resources Information Center

Crone, Linda J.; Tashakkori, Abbas

Findings from a study that sought to determine the degree to which effective schools are uniformly effective for all students regardless of socioeconomic status (SES) are presented in this paper. Data were derived from a large nationally representative set of 989 schools that were involved in the National Education Longitudinal Study (NELS) of…

An Empirical Study of Decisions Involving Post-Secondary Vocational School Training. Volume II--Technical Report. Final Report.

ERIC Educational Resources Information Center

Olson, Lawrence S.

A study examined decisions involving private, postsecondary vocational schooling using three large, national sets of data (from the National Longitudinal Surveys) on males. Particular attention is paid to three target groups: inner-city and rural individuals and dropouts. Various equations were estimated using a life-cycle model of time allocation…

An Empirical Study of Decisions Involving Post-Secondary Vocational School Training. Volume I--Executive Summary. Final Report.

ERIC Educational Resources Information Center

Olson, Lawrence S.

A study examined decisions involving private, postsecondary vocational schooling using three large, national sets of data (from the National Longitudinal Surveys) on males. Particular attention is paid to three target groups--inner-city and rural individuals and dropouts. Various equations were estimated using a life-cycle model of time allocation…

Patterns and Predictors of Disciplinary Exclusion over Time: An Analysis of the SEELS National Data Set

ERIC Educational Resources Information Center

Bowman-Perrott, Lisa; Benz, Michael R.; Hsu, Hsien-Yuan; Kwok, Oi-Man; Eisterhold, Leigh Ann; Zhang, Dalun

2013-01-01

Disciplinary exclusion practices are on the rise nationally, as are concerns about their disproportionate use and lack of effectiveness. This study used data from the Special Education Elementary Longitudinal Study to examine patterns and predictors of disciplinary exclusion over time. Students with emotional/behavioral disorders were most likely…

From Early Starters to Late Finishers? A Longitudinal Study of Early Foreign Language Learning in School

ERIC Educational Resources Information Center

Jaekel, Nils; Schurig, Michael; Florian, Merle; Ritter, Markus

2017-01-01

Foreign language education has now been implemented at the elementary school level across Europe, and early foreign language education has gained traction following language policies set by the European Commission. The long-term effects of an early start, however, have not received ample scientific scrutiny. The present study assessed early…

Perceptions of Healthy Eating: A Qualitative Study of School-Going Children in South India

ERIC Educational Resources Information Center

Swaminathan, S.; Thomas, T.; Kurpad, A. V.; Vaz, M.

2009-01-01

Objective: To document children's views on healthy eating, perceptions of healthy and unhealthy foods and health consequences of consuming unhealthy foods. Design: Baseline data from a three-year longitudinal study. Setting A purposive sample of 307 school children aged 7 to 15 years were recruited from three schools representing various…

Labor Market Returns to Sub-Baccalaureate Credentials: How Much Does a Community College Degree or Certificate Pay?

ERIC Educational Resources Information Center

Dadgar, Mina; Trimble, Madeline Joy

2015-01-01

This study provides one of the first estimates of the returns to different types of community college credentials--short-term certificates, long-term certificates, and associate degrees--across different fields of study. We exploit a rich data set that includes matched, longitudinal college transcripts and Unemployment Insurance records for…

Indicators of Home Care Use in Urban and Rural Settings

ERIC Educational Resources Information Center

Mitchell, Lori A.; Strain, Laurel A.; Blandford, Audrey A.

2007-01-01

This study employs a longitudinal design to examine rural-urban differences in home care service use over time, drawing on data from the Manitoba Study of Health and Aging (MSHA). Characteristics of community-dwelling, cognitively intact adults aged 65 years or older not receiving home care services in the province of Manitoba (n = 855) were…

Arthritis, Rheumatism and Aging Medical Information System Post-Marketing Surveillance Program.

PubMed

Singh, G

2001-05-01

The Arthritis, Rheumatism, and Aging Post-Marketing Surveillance Program (ARAMIS-PMS) is a collection of multicenter, prospective, noninterventional, observational longitudinal studies of patients with rheumatic diseases. The ARAMIS-PMS program aims to study patients in normal clinical setting to evaluate the real-life effectiveness, toxicity, and cost effectiveness of various medications used to treat rheumatic diseases.

A Longitudinal Study to Determine If Wiki Work Builds Community among Agricultural Adult Education Students

ERIC Educational Resources Information Center

Kelsey, Kathleen D.; Lin, Hong; Franke-Dvorak, Tanya C.

2011-01-01

Wiki has been lauded as a tool that enhances collaborative writing in educational settings and moves learners toward a state of communal constructivism (Holmes, Tangney, FitzGibbon, Savage, & Mehan., 2001). Many pedagogical claims exist regarding the benefits of using wiki. However, these claims have rarely been challenged. This study used a…

Are School Counselors Impacting Underrepresented Students' Thinking about Postsecondary Education? A Nationally Representative Study

ERIC Educational Resources Information Center

Cholewa, Blaire; Burkhardt, Christina K.; Hull, Michael F.

2016-01-01

Using the HSLS:09 [High School Longitudinal Study of 2009] data set and social capital theory as a framework, the authors examined which student and school characteristics predicted students' identification of their school counselor as the person who had the most influence in their thinking about postsecondary education (N = 3,239,560). Results…

Good Things Come in Threes: Single-Parent Multigenerational Family Structure and Adolescent Adjustment. JCPR Working Paper.

ERIC Educational Resources Information Center

DeLeire, Thomas; Kalil, Ariel

This research used data from the 1998 National Educational Longitudinal Study to investigate the development of outcomes for adolescents living with single mothers in multigenerational families compared with adolescents living in married families (as well as a disaggregated set of other family structures). The study measured family structure when…

Online communication, compulsive Internet use, and psychosocial well-being among adolescents: a longitudinal study.

PubMed

van den Eijnden, Regina J J M; Meerkerk, Gert-Jan; Vermulst, Ad A; Spijkerman, Renske; Engels, Rutger C M E

2008-05-01

The present study investigated the relationships between adolescents' online communication and compulsive Internet use, depression, and loneliness. The study had a 2-wave longitudinal design with an interval of 6 months. The sample consisted of 663 students, 318 male and 345 female, ages 12 to 15 years. Questionnaires were administered in a classroom setting. The results showed that instant messenger use and chatting in chat rooms were positively related to compulsive Internet use 6 months later. Moreover, in agreement with the well-known HomeNet study (R. Kraut et al., 1998), instant messenger use was positively associated with depression 6 months later. Finally, loneliness was negatively related to instant messenger use 6 months later. (PsycINFO Database Record (c) 2008 APA, all rights reserved).

Measurement and simulation of the RHIC abort kicker longitudinal impedence

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

Abreu,N.P.; Hahn,H.; Choi, E.

2009-09-01

In face of the new upgrades for RHIC the longitudinal impedance of the machine plays an important role in setting the threshold for instabilities and the efficacy of some systems. In this paper we describe the measurement of the longitudinal impedance of the abort kicker for RHIC as well as computer simulations of the structure. The impedance measurement was done by the S{sub 21} wire method covering the frequency range from 9 kHz to 2.5 GHz. We observed a sharp resonance peak around 10 MHz and a broader peak around 20 MHz in both, the real and imaginary part, ofmore » the Z/n. These two peaks account for a maximum imaginary longitudinal impedance of j15 {Omega}, a value an order of magnitude larger than the estimated value of j0.2 {Omega}, which indicates that the kicker is one of the main sources of longitudinal impedance in the machine. A computer model was constructed for simulations in the CST MWS program. Results for the magnet input and the also the beam impedance are compared to the measurements. A more detail study of the system properties and possible changes to reduce the coupling impedance are presented.« less

Longitudinal Beam Diagnostics for the ILC Injectors and Bunch Compressors

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

Piot, Philippe; Bracke, Adam; Demir, Veysel

2010-12-01

We present a diagnostics suite and analyze techniques for setting up the longitudinal beam dynamics in ILC e⁻ injectors and e⁺ and e⁻ bunch compressors. Techniques to measure the first order moments and recover the first order longitudinal transfer map of the injector's intricate bunching scheme are presented. Coherent transition radiation diagnostics needed to measure and monitor the bunch length downstream of the ~5 GeV bunch compressor are investigated using a vector diffraction model.

Longitudinal Mediation Analysis with Time-varying Mediators and Exposures, with Application to Survival Outcomes

PubMed Central

Zheng, Wenjing; van der Laan, Mark

2017-01-01

In this paper, we study the effect of a time-varying exposure mediated by a time-varying intermediate variable. We consider general longitudinal settings, including survival outcomes. At a given time point, the exposure and mediator of interest are influenced by past covariates, mediators and exposures, and affect future covariates, mediators and exposures. Right censoring, if present, occurs in response to past history. To address the challenges in mediation analysis that are unique to these settings, we propose a formulation in terms of random interventions based on conditional distributions for the mediator. This formulation, in particular, allows for well-defined natural direct and indirect effects in the survival setting, and natural decomposition of the standard total effect. Upon establishing identifiability and the corresponding statistical estimands, we derive the efficient influence curves and establish their robustness properties. Applying Targeted Maximum Likelihood Estimation, we use these efficient influence curves to construct multiply robust and efficient estimators. We also present an inverse probability weighted estimator and a nested non-targeted substitution estimator for these parameters. PMID:29387520

Changes in sport and physical activity participation for adolescent females: a longitudinal study.

PubMed

Eime, Rochelle M; Harvey, Jack T; Sawyer, Neroli A; Craike, Melinda J; Symons, Caroline M; Payne, Warren R

2016-07-08

Participation in sport and physical activity is reported to decline during adolescence, particularly for females. However we do not have a clear understanding of changes in the context (i.e., modes and settings) of participation throughout adolescence. This study investigated longitudinal changes in physical activity participation and the specific modes and settings of physical activity, together with cross-sectional comparisons, for two age cohorts of female adolescents. Survey of 729 adolescent girls (489 recruited in Year 7 and 243 in Year 11). Participation in eight different modes/settings was reported. PA was measured using 24-h recall diary and metabolic equivalent weighted energy expenditure (MET-min) in Leisure Time Moderate and Vigorous Physical Activity (LTMVPA) on the previous day was calculated. There were no significant changes in duration or total MET-min of LTMVPA on previous day. However, there were significant changes in the modes/settings of participation across time. Participation in school physical education rose during early adolescence before decreasing significantly, and participation in competitive sport and club sport significantly decreased over time; however there were increases in non-competitive forms of physical activity. Overall levels of physical activity did not significantly decrease over adolescence, which is positive for physical health. However, the transition from structured sport to non-organised physical activity may effect social and psychological health, which needs to be further examined.

Longitudinal Analysis of Mouse SDOCT Volumes

PubMed Central

Antony, Bhavna J.; Carass, Aaron; Lang, Andrew; Kim, Byung-Jin; Zack, Donald J.; Prince, Jerry L.

2017-01-01

Spectral-domain optical coherence tomography (SDOCT), in addition to its routine clinical use in the diagnosis of ocular diseases, has begun to find increasing use in animal studies. Animal models are frequently used to study disease mechanisms as well as to test drug efficacy. In particular, SDOCT provides the ability to study animals longitudinally and non-invasively over long periods of time. However, the lack of anatomical landmarks makes the longitudinal scan acquisition prone to inconsistencies in orientation. Here, we propose a method for the automated registration of mouse SDOCT volumes. The method begins by accurately segmenting the blood vessels and the optic nerve head region in the scans using a pixel classification approach. The segmented vessel maps from follow-up scans were registered using an iterative closest point (ICP) algorithm to the baseline scan to allow for the accurate longitudinal tracking of thickness changes. Eighteen SDOCT volumes from a light damage model study were used to train a random forest utilized in the pixel classification step. The area under the curve (AUC) in a leave-one-out study for the retinal blood vessels and the optic nerve head (ONH) was found to be 0.93 and 0.98, respectively. The complete proposed framework, the retinal vasculature segmentation and the ICP registration, was applied to a secondary set of scans obtained from a light damage model. A qualitative assessment of the registration showed no registration failures. PMID:29138527

Longitudinal analysis of mouse SDOCT volumes

NASA Astrophysics Data System (ADS)

Antony, Bhavna J.; Carass, Aaron; Lang, Andrew; Kim, Byung-Jin; Zack, Donald J.; Prince, Jerry L.

2017-03-01

Spectral-domain optical coherence tomography (SDOCT), in addition to its routine clinical use in the diagnosis of ocular diseases, has begun to fund increasing use in animal studies. Animal models are frequently used to study disease mechanisms as well as to test drug efficacy. In particular, SDOCT provides the ability to study animals longitudinally and non-invasively over long periods of time. However, the lack of anatomical landmarks makes the longitudinal scan acquisition prone to inconsistencies in orientation. Here, we propose a method for the automated registration of mouse SDOCT volumes. The method begins by accurately segmenting the blood vessels and the optic nerve head region in the scans using a pixel classification approach. The segmented vessel maps from follow-up scans were registered using an iterative closest point (ICP) algorithm to the baseline scan to allow for the accurate longitudinal tracking of thickness changes. Eighteen SDOCT volumes from a light damage model study were used to train a random forest utilized in the pixel classification step. The area under the curve (AUC) in a leave-one-out study for the retinal blood vessels and the optic nerve head (ONH) was found to be 0.93 and 0.98, respectively. The complete proposed framework, the retinal vasculature segmentation and the ICP registration, was applied to a secondary set of scans obtained from a light damage model. A qualitative assessment of the registration showed no registration failures.

The Oporto mixed-longitudinal growth, health and performance study. Design, methods and baseline results.

PubMed

Souza, Michele Caroline de; Chaves, Raquel Nichele de; Dos Santos, Fernanda Karina; Gomes, Thayse Natacha Queiroz Ferreira; Santos, Daniel Vilhena E; Borges, Alessandra Silva; Pereira, Sara Isabel Sampaio; Forjaz, Cláudia Lúcia de Moraes; Eisenmann, Joey; Maia, José António Ribeiro

2017-02-01

Studies concerning child and adolescent growth, development, performance and health aimed at the multiple interactions amongst this complex set of variables are not common in the Portuguese speaking countries. The aim of this paper is to address the key ideas, methodology and design of the Oporto Growth, Health and Performance Study (OGHPS). The OGHPS is a multidisciplinary mixed-longitudinal study whose main purpose is to examine the multiple interactions among biological, environmental and lifestyle indicators that affect growth, development, health and performance of Portuguese adolescents aged 10-18 years old. This study briefly presents baseline results for growth, physical fitness and lifestyle behaviours for those participating in the cross-sectional sample (n ≈ 8000). Approximately 30% were over-fat or obese. On average, boys were more physically fit and active than girls. Few adolescents meet the guidelines for sleep duration (≈10%) and eating habits (16.2-24.8%), while 76-85% meet the recommended levels of moderate-to-vigorous physical activity. The OGHPS has an innovative approach due to its mixed-longitudinal design and the broad array of variables. Furthermore, subsequent analyses of the longitudinal data will enable a detailed exploration of important factors affecting the growth trajectories of health and performance variables and will also help to identify some of the most opportune times for interventions in terms of health behaviours.

Learning from Errors: Critical Incident Reporting in Nursing

ERIC Educational Resources Information Center

Gartmeier, Martin; Ottl, Eva; Bauer, Johannes; Berberat, Pascal Oliver

2017-01-01

Purpose: The purpose of this paper is to conceptualize error reporting as a strategy for informal workplace learning and investigate nurses' error reporting cost/benefit evaluations and associated behaviors. Design/methodology/approach: A longitudinal survey study was carried out in a hospital setting with two measurements (time 1 [t1]:…

Advantaged/Disadvantaged School Neighborhoods, Parental Networks, and Parental Involvement at Elementary School

ERIC Educational Resources Information Center

Li, Angran; Fischer, Mary J.

2017-01-01

This article examines the relationship between parental networks and parental school involvement during the elementary school years. Using a large, nationally representative data set of elementary school students--the Early Childhood Longitudinal Study-Kindergarten Cohort--and contextual data from the 2000 U.S. Census, our multilevel analysis…

A Longitudinal Study of Total Quality Management Processes in Business Colleges.

ERIC Educational Resources Information Center

Vazzana, Gary; Elfrink, John; Bachmann, Duane P.

2000-01-01

Surveys of business school deans in 1995 (n=243) and 1998 (n=151) regarding total quality management (TQM) practices revealed increases in mission and strategy development, goal setting, and use of advisory boards and cross-functional teams. Few are using TQM to manage core learning processes. (SK)

Iron metabolism in African American women in the second and third trimesters of high-risk pregnancies

USDA-ARS?s Scientific Manuscript database

Objective: To examine iron metabolism during the second and third trimesters in African American women with high-risk pregnancies. Design: Longitudinal pilot study. Setting: Large, university-based, urban Midwestern U.S. medical center. Participants: Convenience sample of 32 African American wome...

Associations between ankle-brachial index and cognitive function: results from the Lifestyle Interventions and Independence for Elders trial

USDA-ARS?s Scientific Manuscript database

OBJECTIVE: The objective of this study was to evaluate cross-sectional and longitudinal associations between ankle-brachial index (ABI) and indicators of cognitive function. DESIGN: Randomized clinical trial (Lifestyle Interventions and Independence for Elders Trial). SETTING: Eight US academic ce...

The Longitudinal Effects of Behavioral Problems on Academic Performance

ERIC Educational Resources Information Center

Vu, Phuong Anna

2012-01-01

Students' behavior and emotional well being are instrumental for their success in the school setting. The present study examined the effects of behavioral problems on the academic performance of students three years later. The behavioral problems consisted of individual externalizing, internalizing, and inattentive behaviors. Next, this study…

Employer Perceptions of Student Informational Interviewing Skills and Behaviors

ERIC Educational Resources Information Center

Orr, Claudia; Sherony, Bruce; Steinhaus, Carol

2011-01-01

Employers continue to report that soft skills are critically important in obtaining employment and achieving long-term career success. Given the challenging job market for college graduates, business school faculty need to provide practical opportunities for students to develop their soft skills in professional settings. A longitudinal study was…

When Curriculum Does Not Match Readiness.

ERIC Educational Resources Information Center

Jaworski, Anne Porter; Riley, Stephanie Mueller

To evaluate the long term impact of developmental placement, a longitudinal study was initiated with over 500 subjects from a variety of school settings across the state of Michigan. Three groups of subjects were selected: (1) children recommended for a "growth year" before entering kindergarten who followed the recommendation, thus…

Propensity Score Analysis in R: A Software Review

ERIC Educational Resources Information Center

Keller, Bryan; Tipton, Elizabeth

2016-01-01

In this article, we review four software packages for implementing propensity score analysis in R: "Matching, MatchIt, PSAgraphics," and "twang." After briefly discussing essential elements for propensity score analysis, we apply each package to a data set from the Early Childhood Longitudinal Study in order to estimate the…

Developmental Change in Social Responsibility during Adolescence: An Ecological Perspective

ERIC Educational Resources Information Center

Wray-Lake, Laura; Syvertsen, Amy K.; Flanagan, Constance A.

2016-01-01

Social responsibility can be defined as a set of prosocial values representing personal commitments to contribute to community and society. Little is known about developmental change--and predictors of that change--in social responsibility during adolescence. The present study used an accelerated longitudinal research design to investigate the…

Environmental Stimulation, Parental Nurturance and Cognitive Development in Humans

ERIC Educational Resources Information Center

Farah, Martha J.; Betancourt, Laura; Shera, David M.; Savage, Jessica H.; Giannetta, Joan M.; Brodsky, Nancy L.; Malmud, Elsa K.; Hurt, Hallam

2008-01-01

The effects of environmental stimulation and parental nurturance on brain development have been studied extensively in animals. Much less is known about the relations between childhood experience and cognitive development in humans. Using a longitudinally collected data set with ecologically valid in-home measures of childhood experience and later…

Latent Motivational Change in an Academic Setting: A 3-Year Longitudinal Study

ERIC Educational Resources Information Center

Otis, Nancy; Grouzet, Frederick M. E.; Pelletier, Luc G.

2005-01-01

This research examined changes in intrinsic and extrinsic motivation during the transition from junior to senior high school as well as the impact of motivational changes on various educational consequences (i.e., dropout intentions, absenteeism, homework frequency, and educational aspirations). A total of 646 participants completed a…

Understanding the role of conscientiousness in healthy aging: where does the brain come in?

PubMed

Patrick, Christopher J

2014-05-01

In reviewing this impressive series of articles, I was struck by 2 points in particular: (a) the fact that the empirically oriented articles focused on analyses of data from very large samples, with the articles by Friedman, Kern, Hampson, and Duckworth (2014) and Kern, Hampson, Goldbert, and Friedman (2014) highlighting an approach to merging existing data sets through use of "metric bridges" to address key questions not addressable through 1 data set alone, and (b) the fact that the articles as a whole included limited mention of neuroscientific (i.e., brain research) concepts, methods, and findings. One likely reason for the lack of reference to brain-oriented work is the persisting gap between smaller sample size lab-experimental and larger sample size multivariate-correlational approaches to psychological research. As a strategy for addressing this gap and bringing a distinct neuroscientific component to the National Institute on Aging's conscientiousness and health initiative, I suggest that the metric bridging approach highlighted by Friedman and colleagues could be used to connect existing large-scale data sets containing both neurophysiological variables and measures of individual difference constructs to other data sets containing richer arrays of nonphysiological variables-including data from longitudinal or twin studies focusing on personality and health-related outcomes (e.g., Terman Life Cycle study and Hawaii longitudinal studies, as described in the article by Kern et al., 2014). (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Shielding of longitudinal magnetic fields with thin, closely, spaced concentric cylindrical shells with applications to atomic clocks

NASA Technical Reports Server (NTRS)

Wolf, S. A.; Gubser, D. U.; Cox, J. E.

1978-01-01

A general formula is given for the longitudinal shielding effectiveness of N closed concentric cylinders. The use of these equations is demonstrated by application to the design of magnetic shields for hydrogen maser atomic clocks. Examples of design tradeoffs such as size, weight, and material thickness are discussed. Experimental results on three sets of shields fabricated by three manufacturers are presented. Two of the sets were designed employing the techniques described. Agreement between the experimental results and the design calculations is then demonstrated.

Progression of major depression during pregnancy and postpartum: a preliminary study.

PubMed

Shivakumar, Geetha; Johnson, Neysa L; McIntire, Donald D; Leveno, Kenneth

2014-04-01

The purpose of this pilot study was to investigate major depressive symptoms among a high-risk group of pregnant women managed at a tertiary care setting. The study prospectively evaluated pregnant women who met DSM-IV criteria for a major depressive episode (MDE). Psychiatric measures for depression, anxiety and social impairment were administered at monthly intervals during pregnancy and immediate postpartum period. Twenty-four women provided longitudinal data from mid pregnancy to 2 months of postpartum period. 86% of women were clinically symptomatic at the beginning of study during pregnancy and only 32% remained clinically symptomatic at 2 months following delivery reaching. This difference reached a statistical significance level p < 0.001. Pregnant women with prior histories of major depression, comorbid anxiety disorder, histories of domestic violence, and those with uninvolved spouse or partners were more at-risk to be clinically symptomatic in the immediate postpartum period. In a group consisting of largely Latina women at a tertiary care setting, progression of major depression when treated with antidepressant medication(s) is that of an improvement from pregnancy to immediate postpartum period. Further longitudinal studies are needed to assess impact of clinical characteristics and treatment on major depression in larger diverse obstetric group.

Episodic memory change in late adulthood: generalizability across samples and performance indices.

PubMed

Dixon, Roger A; Wahlin, Ake; Maitland, Scott B; Hultsch, David F; Hertzog, Christopher; Bäckman, Lars

2004-07-01

Younger adults recall more information from episodic memory tasks than do older adults. Because longitudinal studies are rare and often incompatible, the extent of actual late-life memory change is not well established. We assemble two different longitudinal samples of normal older adults, each of which is tested twice at a 3-year interval, using a large battery of episodic memory indicators. Together, two-wave data from both the Victoria Longitudinal Study in Canada (n = 400) and the Kungsholmen Project in Sweden (n = 168) cover a 40-year span of adulthood, ranging from 54 to 94 years of age. Principal memory tasks include categorizable word lists, story recall, and random word lists, as well as indicators of cognitive support. Overall, an examination of performance on sets of common and complementary episodic tasks reveals that, for both samples, actual 3-year changes are modest and that, when decline occurs, it is gradual. The exception-greater decline for more supported tasks-suggests that these may be especially sensitive to late-life changes.

Enabling Analysis of Big, Thick, Long, and Wide Data: Data Management for the Analysis of a Large Longitudinal and Cross-National Narrative Data Set.

PubMed

Winskell, Kate; Singleton, Robyn; Sabben, Gaelle

2018-03-01

Distinctive longitudinal narrative data, collected during a critical 18-year period in the history of the HIV epidemic, offer a unique opportunity to examine how young Africans are making sense of evolving developments in HIV prevention and treatment. More than 200,000 young people from across sub-Saharan Africa took part in HIV-themed scriptwriting contests held at eight discrete time points between 1997 and 2014, creating more than 75,000 narratives. This article describes the data reduction and management strategies developed for our cross-national and longitudinal study of these qualitative data. The study aims to inform HIV communication practice by identifying cultural meanings and contextual factors that inform sexual behaviors and social practices, and also to help increase understanding of processes of sociocultural change. We describe our sampling strategies and our triangulating methodologies, combining in-depth narrative analysis, thematic qualitative analysis, and quantitative analysis, which are designed to enable systematic comparison without sacrificing ethnographic richness.

Magnetic field of longitudinal gradient bend

NASA Astrophysics Data System (ADS)

Aiba, Masamitsu; Böge, Michael; Ehrlichman, Michael; Streun, Andreas

2018-06-01

The longitudinal gradient bend is an effective method for reducing the natural emittance in light sources. It is, however, not a common element. We have analyzed its magnetic field and derived a set of formulae. Based on the derivation, we discuss how to model the longitudinal gradient bend in accelerator codes that are used for designing electron storage rings. Strengths of multipole components can also be evaluated from the formulae, and we investigate the impact of higher order multipole components in a very low emittance lattice.

Longitudinal associations between depression and problematic substance use in the Youth Partners in Care study.

PubMed

McKowen, James W; Tompson, Martha C; Brown, Timothy A; Asarnow, Joan R

2013-01-01

Large-scale treatment studies suggest that effective depression treatment and reduced depression are associated with improved substance use outcomes. Yet information is limited regarding the longitudinal association between depressive symptoms and problematic substance use and its predictors, particularly in real-world practice settings. Using latent growth modeling, we examined the (a) longitudinal association between depressive symptoms and problematic substance use, (b) impact of depressive symptoms on problematic substance use, (c) impact of problematic substance use on depressive symptoms, and (d) role of co-occurring symptoms on depression and problematic substance use. Participants were part of the Youth Partners in Care study, an effectiveness trial evaluating a quality improvement intervention for youth depression through primary care. This ethnically diverse sample included youths aged 13 to 21 years screening positive for depression from 5 health care organizations. Participants were followed 4 times over an 18-month period and assessed for both depressive symptoms and problematic substance use. Both depressive symptoms and problematic substance use declined over time. Higher baseline depressive symptoms predicted a slower decline in problematic substance use, but baseline problematic substance use did not predict changes in depressive symptoms. These prospective associations remained robust controlling for co-occurring symptoms. Results support prior large-scale depression studies indicating depression burden negatively impacts substance use outcome and extends these findings to real-world practice settings. Findings underscore the importance of addressing depression severity in youth with concurrent substance use problems, even in the context of comorbid symptoms of anxiety, delinquency, and aggression.

Medication discrepancies across multiple care transitions: A retrospective longitudinal cohort study in Italy.

PubMed

Bonaudo, Marco; Martorana, Maria; Dimonte, Valerio; D'Alfonso, Alessandra; Fornero, Giulio; Politano, Gianfranco; Gianino, Maria Michela

2018-01-01

Medication discrepancies are defined as unexplained differences among regimens across different sites of care. The problem of medication discrepancies that occur during the entire care pathway from hospital admission to a local care setting discharge (namely all types of settings dedicated to formal care other than hospitals) has received little attention in the medical literature. The present study aims to (1) determine the prevalence of medication discrepancies that occur during the entire care pathway from hospital admission to local care setting discharge, (2) describe the discrepancy and medication type, and (3) identify potential risk factors for experiencing medication discrepancies in patient care transitions. Evidence from an integrated health care system, such as the Italian one, may explain results from other studies in different healthcare systems. A retrospective longitudinal cohort study of patients admitted from July 2015 to July 2016 to the Giovanni Bosco Hospital serving Turin, Italy and its surrounding territory was performed. Discrepancies were recorded at the following four care transitions: T1: Hospital admission; T2: Hospital discharge; T3: Admission into local care settings; T4: Discharge from local care settings. All evaluations were based on documented regimens and were performed by a team (doctor, nurse and pharmacists). Of 366 included patients, 25.68% had at least one discrepancy. The most frequent type of discrepancy was from medication omission (N = 74; 71.15%). Only discharge from a long-stay care setting (T4) was significantly associated with the onset of discrepancies (p = 0.045). When considering a lack of adequate documentation, not as missing data but as a discrepancy, 43.72% of patients had at least one discrepancy. This study suggests that an integrated health care system, such as Italian system, may influence the prevalence of discrepancies, thus highlighting the need for structured multidisciplinary and, if possible, computerized medication reconciliation to prevent medication discrepancies and improve the quality of medical documentation.

A Longitudinal Analysis of the Influence of a Peer Run Warm Line Phone Service on Psychiatric Recovery.

PubMed

Dalgin, Rebecca Spirito; Dalgin, M Halim; Metzger, Scott J

2018-05-01

This article focuses on the impact of a peer run warm line as part of the psychiatric recovery process. It utilized data including the Recovery Assessment Scale, community integration measures and crisis service usage. Longitudinal statistical analysis was completed on 48 sets of data from 2011, 2012, and 2013. Although no statistically significant differences were observed for the RAS score, community integration data showed increases in visits to primary care doctors, leisure/recreation activities and socialization with others. This study highlights the complexity of psychiatric recovery and that nonclinical peer services like peer run warm lines may be critical to the process.

A Repeated Trajectory Class Model for Intensive Longitudinal Categorical Outcome

PubMed Central

Lin, Haiqun; Han, Ling; Peduzzi, Peter N.; Murphy, Terrence E.; Gill, Thomas M.; Allore, Heather G.

2014-01-01

This paper presents a novel repeated latent class model for a longitudinal response that is frequently measured as in our prospective study of older adults with monthly data on activities of daily living (ADL) for more than ten years. The proposed method is especially useful when the longitudinal response is measured much more frequently than other relevant covariates. The repeated trajectory classes represent distinct temporal patterns of the longitudinal response wherein an individual’s membership in the trajectory classes may renew or change over time. Within a trajectory class, the longitudinal response is modeled by a class-specific generalized linear mixed model. Effectively, an individual may remain in a trajectory class or switch to another as the class membership predictors are updated periodically over time. The identification of a common set of trajectory classes allows changes among the temporal patterns to be distinguished from local fluctuations in the response. An informative event such as death is jointly modeled by class-specific probability of the event through shared random effects. We do not impose the conditional independence assumption given the classes. The method is illustrated by analyzing the change over time in ADL trajectory class among 754 older adults with 70500 person-months of follow-up in the Precipitating Events Project. We also investigate the impact of jointly modeling the class-specific probability of the event on the parameter estimates in a simulation study. The primary contribution of our paper is the periodic updating of trajectory classes for a longitudinal categorical response without assuming conditional independence. PMID:24519416

A model for incomplete longitudinal multivariate ordinal data.

PubMed

Liu, Li C

2008-12-30

In studies where multiple outcome items are repeatedly measured over time, missing data often occur. A longitudinal item response theory model is proposed for analysis of multivariate ordinal outcomes that are repeatedly measured. Under the MAR assumption, this model accommodates missing data at any level (missing item at any time point and/or missing time point). It allows for multiple random subject effects and the estimation of item discrimination parameters for the multiple outcome items. The covariates in the model can be at any level. Assuming either a probit or logistic response function, maximum marginal likelihood estimation is described utilizing multidimensional Gauss-Hermite quadrature for integration of the random effects. An iterative Fisher-scoring solution, which provides standard errors for all model parameters, is used. A data set from a longitudinal prevention study is used to motivate the application of the proposed model. In this study, multiple ordinal items of health behavior are repeatedly measured over time. Because of a planned missing design, subjects answered only two-third of all items at a given point. Copyright 2008 John Wiley & Sons, Ltd.

Behavioral Manifestations and Parental Correlates of Intolerance of Ambiguity in Young Children.

ERIC Educational Resources Information Center

Harrington, David M.; And Others

The phenomenon of intolerance of ambiguity in young children was investigated in this longitudinal study. Personality data for the total of 120 children in the study were obtained from: (1) descriptions of the children at both 3 and 4 years of age by their teachers, using the California Child Q-set; (2) the children's performance on the Lowenfeld…

Entering the University: The Differentiated Experience of Two Chinese International Students in a New Zealand University

ERIC Educational Resources Information Center

Skyrme, Gillian

2007-01-01

This article draws on findings from a longitudinal study of Chinese international students beginning study in a New Zealand university, and focuses on the very different experience of two students in relation to a single course and its assessment requirements, as they sought ways to negotiate identities as university students in their new setting.…

Development of Teaching Beliefs and the Focus of Change in the Process of Pre-Service ESL Teacher Education

ERIC Educational Resources Information Center

Tang, Eunice Lai-Yiu; Lee, John Chi-Kin; Chun, Cecilia Ka-Wai

2012-01-01

This study sets out to investigate how pre-service ESL teachers shape their beliefs in the process of experimenting with new teaching methods introduced in the teacher education programme. A 4-year longitudinal study was conducted with four randomly selected ESL pre-service teachers. Their theoretical orientations of ESL instruction were tracked…

Breaking the Cycle of Disadvantage: Ties between Educational Attainments, Dropping Out and School-Age Motherhood.

ERIC Educational Resources Information Center

Manlove, Jennifer

This study used current data from a cohort of eighth graders in the National Education Longitudinal Study of 1988 to test whether dropping out of high school and other measures of educational performance and involvement influenced the likelihood of having a school-age birth for whites, blacks, and Hispanics. Three major sets of independent…

School-to-Career and Post-Secondary Education: Evidence from the Philadelphia Educational Longitudinal Study. NBER Working Paper No. 11260

ERIC Educational Resources Information Center

Furstenberg, Frank F., Jr.; Neumark, David

2005-01-01

We study a set of programs implemented in Philadelphia high schools that focus on boosting post-secondary enrollment. These programs are less career oriented than traditional school-to work programs, but are consistent with the broadening of the goals of school-to-work to emphasize post-secondary education. The Philadelphia Longitudinal…

Multicompetence in L2 Language Play: A Longitudinal Case Study

ERIC Educational Resources Information Center

Bell, Nancy; Skalicky, Stephen; Salsbury, Tom

2014-01-01

Humor and language play have been recognized as important aspects of second language (L2) development. Qualitative studies that have documented the forms and functions of language play for adult and child L2 users have taken place largely in classroom settings. In order to gain a fuller understanding of such creative manipulations by L2 users, it…

Modeling Associations among Multivariate Longitudinal Categorical Variables in Survey Data: A Semiparametric Bayesian Approach

ERIC Educational Resources Information Center

Tchumtchoua, Sylvie; Dey, Dipak K.

2012-01-01

This paper proposes a semiparametric Bayesian framework for the analysis of associations among multivariate longitudinal categorical variables in high-dimensional data settings. This type of data is frequent, especially in the social and behavioral sciences. A semiparametric hierarchical factor analysis model is developed in which the…

Longitudinal Prescribing Patterns for Psychoactive Medications in Community-Based Individuals with Developmental Disabilities: Utilization of Pharmacy Records

ERIC Educational Resources Information Center

Lott, I. T.; McGregor, M.; Engelman, L.; Touchette, P.; Tournay, A.; Sandman, C.; Fernandez, G.; Plon, L.; Walsh, D.

2004-01-01

Little is known about longitudinal prescribing practices for psychoactive medications for individuals with intellectual disabilities and developmental disabilities (IDDD) who are living in community settings. Computerized pharmacy records were accessed for 2344 community-based individuals with IDDD for whom a total of 3421 prescriptions were…

A mixed-effects regression model for longitudinal multivariate ordinal data.

PubMed

Liu, Li C; Hedeker, Donald

2006-03-01

A mixed-effects item response theory model that allows for three-level multivariate ordinal outcomes and accommodates multiple random subject effects is proposed for analysis of multivariate ordinal outcomes in longitudinal studies. This model allows for the estimation of different item factor loadings (item discrimination parameters) for the multiple outcomes. The covariates in the model do not have to follow the proportional odds assumption and can be at any level. Assuming either a probit or logistic response function, maximum marginal likelihood estimation is proposed utilizing multidimensional Gauss-Hermite quadrature for integration of the random effects. An iterative Fisher scoring solution, which provides standard errors for all model parameters, is used. An analysis of a longitudinal substance use data set, where four items of substance use behavior (cigarette use, alcohol use, marijuana use, and getting drunk or high) are repeatedly measured over time, is used to illustrate application of the proposed model.

An introduction to analyzing dichotomous outcomes in a longitudinal setting: a NIDRR traumatic brain injury model systems communication.

PubMed

Pretz, Christopher R; Ketchum, Jessica M; Cuthbert, Jeffery P

2014-01-01

An untapped wealth of temporal information is captured within the Traumatic Brain Injury Model Systems National Database. Utilization of appropriate longitudinal analyses can provide an avenue toward unlocking the value of this information. This article highlights 2 statistical methods used for assessing change over time when examination of noncontinuous outcomes is of interest where this article focuses on investigation of dichotomous responses. Specifically, the intent of this article is to familiarize the rehabilitation community with the application of generalized estimating equations and generalized linear mixed models as used in longitudinal studies. An introduction to each method is provided where similarities and differences between the 2 are discussed. In addition, to reinforce the ideas and concepts embodied in each approach, we highlight each method, using examples based on data from the Rocky Mountain Regional Brain Injury System.

A tutorial on count regression and zero-altered count models for longitudinal substance use data

PubMed Central

Atkins, David C.; Baldwin, Scott A.; Zheng, Cheng; Gallop, Robert J.; Neighbors, Clayton

2012-01-01

Critical research questions in the study of addictive behaviors concern how these behaviors change over time - either as the result of intervention or in naturalistic settings. The combination of count outcomes that are often strongly skewed with many zeroes (e.g., days using, number of total drinks, number of drinking consequences) with repeated assessments (e.g., longitudinal follow-up after intervention or daily diary data) present challenges for data analyses. The current article provides a tutorial on methods for analyzing longitudinal substance use data, focusing on Poisson, zero-inflated, and hurdle mixed models, which are types of hierarchical or multilevel models. Two example datasets are used throughout, focusing on drinking-related consequences following an intervention and daily drinking over the past 30 days, respectively. Both datasets as well as R, SAS, Mplus, Stata, and SPSS code showing how to fit the models are available on a supplemental website. PMID:22905895

Parenting Style and Behavior as Longitudinal Predictors of Adolescent Alcohol Use.

PubMed

Minaie, Matin Ghayour; Hui, Ka Kit; Leung, Rachel K; Toumbourou, John W; King, Ross M

2015-09-01

Adolescent alcohol use is a serious problem in Australia and other nations. Longitudinal data on family predictors are valuable to guide parental education efforts. The present study tested Baumrind's proposal that parenting styles are direct predictors of adolescent alcohol use. Latent class modeling was used to investigate adolescent perceptions of parenting styles and multivariate regression to examine their predictive effect on the development of adolescent alcohol use. The data set comprised 2,081 secondary school students (55.9% female) from metropolitan Melbourne, Australia, who completed three waves of annual longitudinal data starting in 2004. Baumrind's parenting styles were significant predictors in unadjusted analyses, but these effects were not maintained in multivariate models that also included parenting behavior dimensions. Family influences on the development of adolescent alcohol use appear to operate more directly through specific family management behaviors rather than through more global parenting styles.

Signal Detection and Monitoring Based on Longitudinal Healthcare Data

PubMed Central

Suling, Marc; Pigeot, Iris

2012-01-01

Post-marketing detection and surveillance of potential safety hazards are crucial tasks in pharmacovigilance. To uncover such safety risks, a wide set of techniques has been developed for spontaneous reporting data and, more recently, for longitudinal data. This paper gives a broad overview of the signal detection process and introduces some types of data sources typically used. The most commonly applied signal detection algorithms are presented, covering simple frequentistic methods like the proportional reporting rate or the reporting odds ratio, more advanced Bayesian techniques for spontaneous and longitudinal data, e.g., the Bayesian Confidence Propagation Neural Network or the Multi-item Gamma-Poisson Shrinker and methods developed for longitudinal data only, like the IC temporal pattern detection. Additionally, the problem of adjustment for underlying confounding is discussed and the most common strategies to automatically identify false-positive signals are addressed. A drug monitoring technique based on Wald’s sequential probability ratio test is presented. For each method, a real-life application is given, and a wide set of literature for further reading is referenced. PMID:24300373

Participation Dynamics in Population-Based Longitudinal HIV Surveillance in Rural South Africa

PubMed Central

Larmarange, Joseph; Mossong, Joël; Bärnighausen, Till; Newell, Marie Louise

2015-01-01

Population-based HIV surveillance is crucial to inform understanding of the HIV pandemic and evaluate HIV interventions, but little is known about longitudinal participation patterns in such settings. We investigated the dynamics of longitudinal participation patterns in a high HIV prevalence surveillance setting in rural South Africa between 2003 and 2012, taking into account demographic dynamics. At any given survey round, 22,708 to 30,495 persons were eligible. Although the yearly participation rates were relatively modest (26% to 46%), cumulative rates increased substantially with multiple recruitment opportunities: 68% of eligible persons participated at least once, 48% at least twice and 31% at least three times after five survey rounds. We identified two types of study fatigue: at the individual level, contact and consent rates decreased with multiple recruitment opportunities and, at the population level, these rates also decreased over calendar time, independently of multiple recruitment opportunities. Using sequence analysis and hierarchical clustering, we identified three broad individual participation profiles: consenters (20%), switchers (43%) and refusers (37%). Men were over represented among refusers, women among consenters, and temporary non-residents among switchers. The specific subgroup of persons who were systemically not contacted or refusers constitutes a challenge for population-based surveillance and interventions. PMID:25875851

The persistence of personal and social themes in context: Long- and short-term studies of students' scientific ideas

NASA Astrophysics Data System (ADS)

Helldén, Gustav F.; Solomon, Joan

2004-11-01

In this paper we will examine the persistence of misconceptions. We used data from a longitudinal study of personal ideas in 24 students' thinking about ecological processes. The results show students often speaking about personal experiences dating from an early age, to which they had also referred in similar interviews conducted years before. These data are compared with results from a different study of middle school physics students' thinking about energy and steam engines. After the new learning had been successfull completed and assessed, old ideas returned. These findings are used to set up a theoretical basis for understanding the longitudinal results. Findings from memory studies are shown to explicate the long-term effects of the passage of time and prompts for the recall of scientific concepts.

A patient-centered longitudinal care plan: vision versus reality

PubMed Central

Dykes, Patricia C; Samal, Lipika; Donahue, Moreen; Greenberg, Jeffrey O; Hurley, Ann C; Hasan, Omar; O'Malley, Terrance A; Venkatesh, Arjun K; Volk, Lynn A; Bates, David W

2014-01-01

Objective As healthcare systems and providers move toward meaningful use of electronic health records, longitudinal care plans (LCPs) may provide a means to improve communication and coordination as patients transition across settings. The objective of this study was to determine the current state of communication of LCPs across settings and levels of care. Materials and methods We conducted surveys and interviews with professionals from emergency departments, acute care hospitals, skilled nursing facilities, and home health agency settings in six regions in the USA. We coded the transcripts according to the Agency for Healthcare Research and Quality (AHRQ) ‘Broad Approaches’ to care coordination to understand the degree to which current practice meets the definition of an LCP. Results Participants (n=22) from all settings reported that LCPs do not exist in their current state. We found LCPs in practice, and none of these were shared or reconciled across settings. Moreover, we found wide variation in the types and formats of care plan information that was communicated as patients transitioned. The most common formats, even when care plan information was communicated within the same healthcare system, were paper and fax. Discussion These findings have implications for data reuse, interoperability, and achieving widespread adoption of LCPs. Conclusions The use of LCPs to support care transitions is suboptimal. Strategies are needed to transform the LCP from vision to reality. PMID:24996874

Wind-tunnel investigation of the powered low-speed longitudinal aerodynamics of the Vectored-Engine-Over (VEO) wing fighter configuration

NASA Technical Reports Server (NTRS)

Paulson, J. W.; Whitten, P. D.; Stumpfl, S. C.

1982-01-01

A wind-tunnel investigation incorporating both static and wind-on testing was conducted in the Langley 4- by 7-Meter Tunnel to determine the effects of vectored thrust along with spanwise blowing on the low-speed aerodynamics of an advanced fighter configuration. Data were obtained over a large range of thrust coefficients corresponding to takeoff and landing thrust settings for many nozzle configurations. The complete set of static thrust data and the complete set of longitudinal aerodynamic data obtained in the investigation are presented. These data are intended for reference purposes and, therefore, are presented without analysis or comment. The analysis of the thrust-induced effects found in the investigation are not discussed.

The Impact of Caregivers' Interrogative Styles in English and Japanese on Early Bilingual Development

ERIC Educational Resources Information Center

Nakamura, Janice; Quay, Suzanne

2012-01-01

This study examines the relationship between caregivers' conversational styles in One-Person-One-Language (OPOL) settings and early bilingual development. In particular, it attempts to demonstrate that interrogative styles may have an impact on bilingual children's responsiveness in two language contexts. It is based on longitudinal data of a…

Pattern Language Development in the Preparation of Inclusive Educators

ERIC Educational Resources Information Center

Bain, Alan; Lancaster, Julie; Zundans, Lucia

2008-01-01

Pattern language is the lexicon used to express the schema of a field of professional practice (Smethurst, 1997). This lexicon is frequently presumed to exist in communities of practice in educational settings, although the findings derived from the longitudinal study of schools (Elmore, 1996; Goodlad, 1984; Lortie, 1975; McLaughlin & Talbert,…

Preschool Experience in 10 Countries: Cognitive and Language Performance at Age 7

ERIC Educational Resources Information Center

Montie, Jeanne E.; Xiang, Zongping; Schweinhart, Lawrence J.

2006-01-01

The IEA Preprimary Project is a longitudinal, cross-national study of preprimary care and education designed to identify how process and structural characteristics of the settings children attended at age 4 are related to their age-7 cognitive and language performance. Investigators collaborated to develop common instruments to measure family…

Pathways to a STEMM Profession

ERIC Educational Resources Information Center

Miller, Jon D.; Kimmel, Linda G.

2012-01-01

The inadequate number of American young adults selecting a scientific or engineering profession continues to be a major national concern. Using data from the 23-year record of the Longitudinal Study of American Youth (LSAY) and working within the social learning paradigm, this analysis uses a set of 21 variables to predict young people's…

Influences on Children's Human Capital in Rural Malawi: Three Essays

ERIC Educational Resources Information Center

Appiah-Yeboah, Shirley Afua

2013-01-01

The circumstances that characterize poor, rural communities in Malawi suggest that children's health-wealth gradient can vary from other settings. This dissertation begins with a description of the methods used to create a household wealth variable using assets data in the Malawi Longitudinal Study of Families and Health project. By using a fixed…

Assessing Long-Term Outcomes of an Intervention Designed for Pregnant Incarcerated Women

ERIC Educational Resources Information Center

Kubiak, Sheryl Pimlott; Kasiborski, Natalie; Schmittel, Emily

2010-01-01

Objectives: Approximately 25% of women are pregnant or postpartum when they enter prison. This study assesses a system-level intervention that prevented the separation of mothers and infants at birth, allowing them to reside together in an alternative community setting. Method: Longitudinal analysis of several state-level administrative databases…

Development and Validation of a Unidimensional Maltreatment Scale in the Add Health Data Set

ERIC Educational Resources Information Center

Marszalek, Jacob M.; Hamilton, Jessica L.

2012-01-01

Four maltreatment items were examined from Wave III (N = 13,516) of the National Longitudinal Study of Adolescent Health. Item analysis, confirmatory factor analysis, cross-validation, reliability estimates, and convergent validity coefficients strongly supported the validity of using the four items as a unidimensional composite. Implications for…

Connecting Teacher Professional Development and Student Mathematics Achievement: Mediating Belonging With Multimodal Explorations in Language, Identity, and Culture

ERIC Educational Resources Information Center

Kutaka, Traci Shizu; Smith, Wendy M.; Albano, Anthony D.; Edwards, Carolyn Pope; Ren, Lixin; Beattie, Heidi Lynn; Lewis, W. James; Heaton, Ruth M.; Stroup, Walter W.

2017-01-01

The present study investigated the effects of "Primarily Math", an inservice elementary mathematics specialist program. "Primarily Math" sought to augment the mathematical knowledge for teaching of kindergarten through third-grade teachers using a longitudinal multiple cohort design. Two sets of analyses were conducted. The…

After-School Programs as a Prosocial Setting for Bonding between Peers

ERIC Educational Resources Information Center

Wright, Robin; John, Lindsay; Duku, Eric; Burgos, Giovani; Krygsman, Amanda; Esposto, Charlene

2009-01-01

This study reports on the longitudinal analysis of a structured after-school arts program for Canadian youth, ages 9 to 15 years, from low-income communities where the relationship of peer social support, family interactions, and psychosocial outcomes is evaluated. Multi-level growth curve analyses suggest an increase in prosocial development with…

Changes in Weight and Health Behaviors from Freshman through Senior Year of College

ERIC Educational Resources Information Center

Racette, Susan B.; Deusinger, Susan S.; Strube, Michael J.; Highstein, Gabrielle R.; Deusinger, Robert H.

2008-01-01

Objective: To assess weight changes, exercise and diet behaviors among college students from the beginning of freshman year until the end of senior year. Design: Longitudinal observational study. Setting: Private university in St. Louis, Missouri. Participants: College students (138 females, 66 males). Main Outcome Measures: Weight and height were…

The Changing World View of Minority Migrants in an Urban Setting.

ERIC Educational Resources Information Center

Shannon, Lyle W.

A series of "world view" or value orientation questions were utilized in generating scale scores that sharply differentiated representative samples of Mexican Americans (280), Negroes (280), and Anglos (413) in a longitudinal study. The original interviews were conducted in 1959, 1960, and 1961. In 1971, seventy-four percent of the original…

The Returned Prisoner of War: Factors in Family Reintegration

ERIC Educational Resources Information Center

McCubin, Hamilton I.; And Others

1975-01-01

Longitudinal study on 48 families of returned prisoners of war to identify factors to explain degree of reintegration of returnee into his family system. Four sets of data were considered: (1) background characteristics of husband and wife; (2) indices of family preparedness; (3) returnees' prison experiences and their psychiatric status; (4)…

Patterns of Non-Verbal Social Interactions within Intensive Mathematics Intervention Contexts

ERIC Educational Resources Information Center

Thomas, Jonathan Norris; Harkness, Shelly Sheats

2016-01-01

This study examined the non-verbal patterns of interaction within an intensive mathematics intervention context. Specifically, the authors draw on social constructivist worldview to examine a teacher's use of gesture in this setting. The teacher conducted a series of longitudinal teaching experiments with a small number of young, school-age…

Examining External and Internal Poverty as Antecedents of Teen Pregnancy

ERIC Educational Resources Information Center

Young, Tamera; Turner, Jean; Denny, George; Young, Michael

2004-01-01

Objectives: To identify antecedents of teen pregnancy. Methods: Data from the National Education Longitudinal Study were analyzed. This data set allowed us to identify eighth-grade antecedents of teen pregnancy/childbearing. Results: The variables that were found to be most predictive of later pregnancy were reflective of internal poverty (locus…

Destination Unknown? Study Choices and Graduate Destinations of Hungarian Youth in Slovakia

ERIC Educational Resources Information Center

Pásztor, Adél

2018-01-01

Focusing on Hungarian minority youth in a rural Slovakian setting, this article analyses their higher education aspirations and choices amidst significant economic, political and educational reforms. Relying on mixed methods and a longitudinal design, the research follows a cohort of high school students from their last year of secondary school…

Doing the Scut Work of Infant Care: Does Religiousness Encourage Father Involvement?

ERIC Educational Resources Information Center

DeMaris, Alfred; Mahoney, Annette; Pargament, Kenneth I.

2011-01-01

Considerable debate exists regarding whether religiousness promotes or impedes greater father involvement in parenting. Our study addresses this issue using a Midwestern longitudinal data set that tracks the transition to first parenthood for 169 married couples. We focus on performance of the "messier" tasks of infant care. We find little…

Age-Dependent and Age-Independent Measures of Locus of Control.

ERIC Educational Resources Information Center

Sherman, Lawrence W.; Hofmann, Richard

Using a longitudinal data set obtained from 169 pre-adolescent children between the ages of 8 and 13 years, this study statistically divided locus of control into two independent components. The first component was noted as "age-dependent" (AD) and was determined by predicted values generated by regressing children's ages onto their…

Teacher Effects and Teacher-Related Policies

ERIC Educational Resources Information Center

Jackson, C. Kirabo; Rockoff, Jonah E.; Staiger, Douglas O.

2014-01-01

The emergence of large longitudinal data sets linking students to teachers has led to rapid growth in the study of teacher effects on student outcomes by economists over the past decade. One large literature has documented wide variation in teacher effectiveness that is not well explained by observable student or teacher characteristics. A second…

Pre-Veterinary Medical Grade Point Averages as Predictors of Academic Success in Veterinary College.

ERIC Educational Resources Information Center

Julius, Marcia F.; Kaiser, Herbert E.

1978-01-01

A five-year longitudinal study was designed to find the best predictors of academic success in veterinary school at Kansas State University and to set up a multiple regression formula to be used in selecting students. The preveterinary grade point average was found to be the best predictor. (JMD)

Rural Agricultural Change and Fertility Transition in Nepal

ERIC Educational Resources Information Center

Bhandari, Prem; Ghimire, Dirgha

2013-01-01

Using longitudinal panel data from the Western Chitwan Valley of Nepal, this study examines the impact of the use of modern farm technologies on fertility transition--specifically, the number of births in a farm household. Previous explanations for the slow pace of fertility transition in rural agricultural settings often argued that the demand…

The Emergent Practice of Infant Compliance: An Exploration in Two Cultures

ERIC Educational Resources Information Center

Reddy, Vasudevi; Liebal, Katja; Hicks, Kerry; Jonnalagadda, Srujana; Chintalapuri, Beena

2013-01-01

Complying with directives is an important indicator of developing cooperativeness and of the awareness of others' intentions for one's own actions. Nonetheless, little is known about the early emergence of compliance. In the present longitudinal study, we explore this phenomenon in naturalistic settings in two cultural groups. Nine middle-class…

Positive psychology in rehabilitation medicine: a brief report.

PubMed

Bertisch, Hilary; Rath, Joseph; Long, Coralynn; Ashman, Teresa; Rashid, Tayyab

2014-01-01

The field of positive psychology has grown exponentially within the last decade. To date, however, there have been few empirical initiatives to clarify the constructs within positive psychology as they relate to rehabilitation medicine. Character strengths, and in particular resilience, following neurological trauma are clinically observable within rehabilitation settings, and greater knowledge of the way in which these factors relate to treatment variables may allow for enhanced treatment conceptualization and planning. The goal of this study was to explore the relationships between positive psychology constructs (character strengths, resilience, and positive mood) and rehabilitation-related variables (perceptions of functional ability post-injury and beliefs about treatment) within a baseline data set, a six-month follow-up data set, and longitudinally across time points. Pearson correlations and supplementary multiple regression analyses were conducted within and across these time points from a starting sample of thirty-nine individuals with acquired brain injury (ABI) in an outpatient rehabilitation program. Positive psychology constructs were related to rehabilitation-related variables within the baseline data set, within the follow-up data set, and longitudinally between baseline positive psychology variables and follow-up rehabilitation-related data. These preliminary findings support relationships between character strengths, resilience, and positive mood states with perceptions of functional ability and expectations of treatment, respectively, which are primary factors in treatment success and quality of life outcomes in rehabilitation medicine settings. The results suggest the need for more research in this area, with an ultimate goal of incorporating positive psychology constructs into rehabilitation conceptualization and treatment planning.

Hypothesis testing in functional linear regression models with Neyman's truncation and wavelet thresholding for longitudinal data.

PubMed

Yang, Xiaowei; Nie, Kun

2008-03-15

Longitudinal data sets in biomedical research often consist of large numbers of repeated measures. In many cases, the trajectories do not look globally linear or polynomial, making it difficult to summarize the data or test hypotheses using standard longitudinal data analysis based on various linear models. An alternative approach is to apply the approaches of functional data analysis, which directly target the continuous nonlinear curves underlying discretely sampled repeated measures. For the purposes of data exploration, many functional data analysis strategies have been developed based on various schemes of smoothing, but fewer options are available for making causal inferences regarding predictor-outcome relationships, a common task seen in hypothesis-driven medical studies. To compare groups of curves, two testing strategies with good power have been proposed for high-dimensional analysis of variance: the Fourier-based adaptive Neyman test and the wavelet-based thresholding test. Using a smoking cessation clinical trial data set, this paper demonstrates how to extend the strategies for hypothesis testing into the framework of functional linear regression models (FLRMs) with continuous functional responses and categorical or continuous scalar predictors. The analysis procedure consists of three steps: first, apply the Fourier or wavelet transform to the original repeated measures; then fit a multivariate linear model in the transformed domain; and finally, test the regression coefficients using either adaptive Neyman or thresholding statistics. Since a FLRM can be viewed as a natural extension of the traditional multiple linear regression model, the development of this model and computational tools should enhance the capacity of medical statistics for longitudinal data.

A Comparison of the Long-Term Learning Effects of Comprehensive and Topic-Specific Practice Set Assignments

ERIC Educational Resources Information Center

Fatemi, Darius; Marley, Robert; Marquis, Linda M.

2015-01-01

The authors examined the long-term learning effects of two different practice set assignment approaches on business students' long-term learning: a comprehensive, multiple-period practice set and a topic-specific practice set. Student learning was measured longitudinally across semesters. The authors found evidence that students using a…

Type of childcare at 18 months--I. Differences in interactional experience.

PubMed

Melhuish, E C; Mooney, A; Martin, S; Lloyd, E

1990-09-01

A longitudinal study has followed two-parent families and their first-born child. The families were chosen so that there were three groups of dual-earner families using relatives, childminders and nurseries for day care and one group of single-earner families. At 18 mths of age children in the study were observed in the four types of childcare setting. The data from the detailed observations were used to compare the children's interactional experience. The results indicate marked variation in the quality of children's experiences between different childcare settings. Possible reasons for such variation are discussed.

Model uncertainty and multimodel inference in reliability estimation within a longitudinal framework.

PubMed

Alonso, Ariel; Laenen, Annouschka

2013-05-01

Laenen, Alonso, and Molenberghs (2007) and Laenen, Alonso, Molenberghs, and Vangeneugden (2009) proposed a method to assess the reliability of rating scales in a longitudinal context. The methodology is based on hierarchical linear models, and reliability coefficients are derived from the corresponding covariance matrices. However, finding a good parsimonious model to describe complex longitudinal data is a challenging task. Frequently, several models fit the data equally well, raising the problem of model selection uncertainty. When model uncertainty is high one may resort to model averaging, where inferences are based not on one but on an entire set of models. We explored the use of different model building strategies, including model averaging, in reliability estimation. We found that the approach introduced by Laenen et al. (2007, 2009) combined with some of these strategies may yield meaningful results in the presence of high model selection uncertainty and when all models are misspecified, in so far as some of them manage to capture the most salient features of the data. Nonetheless, when all models omit prominent regularities in the data, misleading results may be obtained. The main ideas are further illustrated on a case study in which the reliability of the Hamilton Anxiety Rating Scale is estimated. Importantly, the ambit of model selection uncertainty and model averaging transcends the specific setting studied in the paper and may be of interest in other areas of psychometrics. © 2012 The British Psychological Society.

Limited genetic covariance between autistic traits and intelligence: findings from a longitudinal twin study.

PubMed

Hoekstra, Rosa A; Happé, Francesca; Baron-Cohen, Simon; Ronald, Angelica

2010-07-01

Intellectual disability is common in individuals with autism spectrum conditions. However, the strength of the association between both conditions and its relevance to finding the underlying (genetic) causes of autism is unclear. This study aimed to investigate the longitudinal association between autistic traits and intelligence in a general population twin sample and to examine the etiology of this association. Parental ratings of autistic traits and performance on intelligence tests were collected in a sample of 8,848 twin pairs when the children were 7/8, 9, and 12 years old. Phenotypic and longitudinal correlations in the sample as a whole were compared to the associations in the most extreme scoring 5% of the population. The genetic and environmental influences on the overlap between autistic traits and IQ and on the stability of this relationship over time were estimated using structural equation modeling. Autistic traits were modestly negatively correlated to intellectual ability, both in the extreme scoring groups and among the full-range scores. The correlation was stable over time and was mainly explained by autistic trait items assessing communication difficulties. Genetic model fitting showed that autistic traits and IQ were influenced by a common set of genes and a common set of environmental influences that continuously affect these traits throughout childhood. The genetic correlation between autistic traits and IQ was only modest. These findings suggest that individual differences in autistic traits are substantially genetically independent of intellectual functioning. The relevance of these findings to future studies is discussed. (c) 2010 Wiley-Liss, Inc.

NLS Handbook, 2005. National Longitudinal Surveys

ERIC Educational Resources Information Center

Bureau of Labor Statistics, 2006

2006-01-01

The National Longitudinal Surveys (NLS), sponsored by the U.S. Bureau of Labor Statistics (BLS), are a set of surveys designed to gather information at multiple points in time on the labor market experiences of groups of men and women. Each of the cohorts has been selected to represent all people living in the United States at the initial…

Latent Variable Regression 4-Level Hierarchical Model Using Multisite Multiple-Cohorts Longitudinal Data. CRESST Report 801

ERIC Educational Resources Information Center

Choi, Kilchan

2011-01-01

This report explores a new latent variable regression 4-level hierarchical model for monitoring school performance over time using multisite multiple-cohorts longitudinal data. This kind of data set has a 4-level hierarchical structure: time-series observation nested within students who are nested within different cohorts of students. These…

A varying-coefficient method for analyzing longitudinal clinical trials data with nonignorable dropout

PubMed Central

Forster, Jeri E.; MaWhinney, Samantha; Ball, Erika L.; Fairclough, Diane

2011-01-01

Dropout is common in longitudinal clinical trials and when the probability of dropout depends on unobserved outcomes even after conditioning on available data, it is considered missing not at random and therefore nonignorable. To address this problem, mixture models can be used to account for the relationship between a longitudinal outcome and dropout. We propose a Natural Spline Varying-coefficient mixture model (NSV), which is a straightforward extension of the parametric Conditional Linear Model (CLM). We assume that the outcome follows a varying-coefficient model conditional on a continuous dropout distribution. Natural cubic B-splines are used to allow the regression coefficients to semiparametrically depend on dropout and inference is therefore more robust. Additionally, this method is computationally stable and relatively simple to implement. We conduct simulation studies to evaluate performance and compare methodologies in settings where the longitudinal trajectories are linear and dropout time is observed for all individuals. Performance is assessed under conditions where model assumptions are both met and violated. In addition, we compare the NSV to the CLM and a standard random-effects model using an HIV/AIDS clinical trial with probable nonignorable dropout. The simulation studies suggest that the NSV is an improvement over the CLM when dropout has a nonlinear dependence on the outcome. PMID:22101223

Longitudinal analyses of the DNA methylome in deployed military servicemen identify susceptibility loci for post-traumatic stress disorder.

PubMed

Rutten, B P F; Vermetten, E; Vinkers, C H; Ursini, G; Daskalakis, N P; Pishva, E; de Nijs, L; Houtepen, L C; Eijssen, L; Jaffe, A E; Kenis, G; Viechtbauer, W; van den Hove, D; Schraut, K G; Lesch, K-P; Kleinman, J E; Hyde, T M; Weinberger, D R; Schalkwyk, L; Lunnon, K; Mill, J; Cohen, H; Yehuda, R; Baker, D G; Maihofer, A X; Nievergelt, C M; Geuze, E; Boks, M P M

2018-05-01

In order to determine the impact of the epigenetic response to traumatic stress on post-traumatic stress disorder (PTSD), this study examined longitudinal changes of genome-wide blood DNA methylation profiles in relation to the development of PTSD symptoms in two prospective military cohorts (one discovery and one replication data set). In the first cohort consisting of male Dutch military servicemen (n=93), the emergence of PTSD symptoms over a deployment period to a combat zone was significantly associated with alterations in DNA methylation levels at 17 genomic positions and 12 genomic regions. Evidence for mediation of the relation between combat trauma and PTSD symptoms by longitudinal changes in DNA methylation was observed at several positions and regions. Bioinformatic analyses of the reported associations identified significant enrichment in several pathways relevant for symptoms of PTSD. Targeted analyses of the significant findings from the discovery sample in an independent prospective cohort of male US marines (n=98) replicated the observed relation between decreases in DNA methylation levels and PTSD symptoms at genomic regions in ZFP57, RNF39 and HIST1H2APS2. Together, our study pinpoints three novel genomic regions where longitudinal decreases in DNA methylation across the period of exposure to combat trauma marks susceptibility for PTSD.

The Mother-Child Playgroup as Socialisation Context: A Short-Term Longitudinal Study of Mother-Child-Peer Relationship Dynamics

ERIC Educational Resources Information Center

Mize, Jacquelyn; Pettit, Gregory S.

2010-01-01

This study employed mother-child playgroups as a context for examining mothers' supervision of child-peer interactions and children's adaptation to a new peer-group setting. Six playgroups, consisting of quartets of mothers and their 24- to 54-month-old children (n = 23), were observed in ten 90-minute sessions. All mothers attended the first two…

I-States-as-Objects-Analysis (ISOA): Extensions of an Approach to Studying Short-Term Developmental Processes by Analyzing Typical Patterns

ERIC Educational Resources Information Center

Bergman, Lars R.; Nurmi, Jari-Erik; von Eye, Alexander A.

2012-01-01

I-states-as-objects-analysis (ISOA) is a person-oriented methodology for studying short-term developmental stability and change in patterns of variable values. ISOA is based on longitudinal data with the same set of variables measured at all measurement occasions. A key concept is the "i-state," defined as a person's pattern of variable…

The Relationship between Adolescents' News Media Use and Civic Engagement: The Indirect Effect of Interpersonal Communication with Parents

ERIC Educational Resources Information Center

Boyd, Michelle J.; Zaff, Jonathan F.; Phelps, Erin; Weiner, Michelle B.; Lerner, Richard M.

2011-01-01

Using data from the 4-H Study of Positive Youth Development, a longitudinal study involving U.S. adolescents, multi-group structural equation modeling (SEM) was used to evaluate whether news media use is predictive of a set of civic indicators (civic duty, civic efficacy, neighborhood social connection, and civic participation) for youth in Grades…

The Development of Approaches to Learning and Perceptions of the Teaching-Learning Environment during Bachelor Level Studies and Their Relation to Study Success

ERIC Educational Resources Information Center

Asikainen, Henna; Parpala, Anna; Lindblom-Ylänne, Sari; Vanthournout, Gert; Coertjens, Liesje

2014-01-01

The aim of the present study is to explore changes both in approaches to learning as well as in students' experiences of the teaching-learning environment and how these changes are related to each other during their Bachelor studies by using a longitudinal data set. The aim is further to explore how students' approaches to learning and their…

An Investigation of GeoBase Mission Data Set Design, Implementation, and Usage Within Air Force Civil Engineer Electrical and Utilities Work Centers

DTIC Science & Technology

2005-03-01

ethnography , grounded theory , phenomenological , case study , and content analysis. As ethnography is based upon a longitudinal study in...a qualitative methodology consisting of a case study strategy is warranted for this research project. Yin (2003) lists five components of research ...systems. Journal of End User Computing, 12(3), 14. Yin, R. K. (2003). Case Study Research : Design and

Adolescent Gender-Related Abuse, Androphilia, and HIV Risk Among Transfeminine People of Color in New York City

PubMed Central

Hwahng, Sel J.; Nuttbrock, Larry

2014-01-01

Public health research has indicated extremely high HIV seroprevalence (13–63%) among low-income transfeminine people of color of African, Latina, and Asian descent living in the U.S. This paper combines two data sets. One set is based on an ethnographic study (N=50, 120 hours of participant observation). The other set longitudinal quantitative study (baseline N=600, N=275 followed for 3 years). Transfeminine people of color are much more likely to be androphilic and at high HIV risk. A greater understanding of adolescent gender-related abuse and trauma-impacted androphilia contributes towards a holistic conceptual model of HIV risk. A theoretical model is proposed that incorporates findings from both studies and integrates sociostructural, interpersonal, and intrapsychic levels of HIV risk. PMID:24294927

Does contextual unemployment matter for health status across the life course? A longitudinal multilevel study exploring the link between neighbourhood unemployment and functional somatic symptoms.

PubMed

Brydsten, Anna; Gustafsson, Per E; Hammarström, Anne; San Sebastian, Miguel

2017-01-01

This study examines whether neighbourhood unemployment is related to functional somatic symptoms, independently of the individual employment, across the life course and at four specific life course periods (age 16, 21, 30 and 42). Self-reported questioner data was used from a 26-year prospective Swedish cohort (n=1010) with complementary neighbourhood register data. A longitudinal and a set of age-specific cross-sectional hierarchal linear regressions was carried out. The results suggest that living in a neighbourhood with high unemployment has implications for residents' level of functional somatic symptoms, regardless of their own unemployment across time, particularly at age 30. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Comparison of longitudinal excursion of a nerve-phantom model using quantitative ultrasound imaging and motion analysis system methods: A convergent validity study.

PubMed

Paquette, Philippe; El Khamlichi, Youssef; Lamontagne, Martin; Higgins, Johanne; Gagnon, Dany H

2017-08-01

Quantitative ultrasound imaging is gaining popularity in research and clinical settings to measure the neuromechanical properties of the peripheral nerves such as their capability to glide in response to body segment movement. Increasing evidence suggests that impaired median nerve longitudinal excursion is associated with carpal tunnel syndrome. To date, psychometric properties of longitudinal nerve excursion measurements using quantitative ultrasound imaging have not been extensively investigated. This study investigates the convergent validity of the longitudinal nerve excursion by comparing measures obtained using quantitative ultrasound imaging with those determined with a motion analysis system. A 38-cm long rigid nerve-phantom model was used to assess the longitudinal excursion in a laboratory environment. The nerve-phantom model, immersed in a 20-cm deep container filled with a gelatin-based solution, was moved 20 times using a linear forward and backward motion. Three light-emitting diodes were used to record nerve-phantom excursion with a motion analysis system, while a 5-cm linear transducer allowed simultaneous recording via ultrasound imaging. Both measurement techniques yielded excellent association ( r  = 0.99) and agreement (mean absolute difference between methods = 0.85 mm; mean relative difference between methods = 7.48 %). Small discrepancies were largely found when larger excursions (i.e. > 10 mm) were performed, revealing slight underestimation of the excursion by the ultrasound imaging analysis software. Quantitative ultrasound imaging is an accurate method to assess the longitudinal excursion of an in vitro nerve-phantom model and appears relevant for future research protocols investigating the neuromechanical properties of the peripheral nerves.

Longitudinal patterns of California Medicaid recipients with acquired immunodeficiency syndrome

PubMed Central

Andrews, Roxanne; Keyes, Margaret; Pine, Penelope

1991-01-01

In this study, the authors examine the longitudinal experience, annual trends, and subpopulation differences in Medicaid use and expenditures for persons with acquired immunodeficiency syndrome (AIDS) in California from 1983 through 1986. About two-thirds of adult males were enrolled in Medicaid within 1 month of their AIDS diagnosis. These recipients averaged approximately 20-percent higher lifetime expenditures than those enrolled at a later time. Monthly expenditures were higher in the beginning of enrollment and prior to death than in the months in between. From 1983 through 1986, there was a shift of care from inpatient to outpatient settings. In 1986, children and adult females had higher median expenditures than did adult males. PMID:10122357

Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition

PubMed Central

Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John

2013-01-01

BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition. PMID:24961428

Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition.

PubMed

Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John

2013-05-28

BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition.

Bayesian model selection techniques as decision support for shaping a statistical analysis plan of a clinical trial: An example from a vertigo phase III study with longitudinal count data as primary endpoint

PubMed Central

2012-01-01

Background A statistical analysis plan (SAP) is a critical link between how a clinical trial is conducted and the clinical study report. To secure objective study results, regulatory bodies expect that the SAP will meet requirements in pre-specifying inferential analyses and other important statistical techniques. To write a good SAP for model-based sensitivity and ancillary analyses involves non-trivial decisions on and justification of many aspects of the chosen setting. In particular, trials with longitudinal count data as primary endpoints pose challenges for model choice and model validation. In the random effects setting, frequentist strategies for model assessment and model diagnosis are complex and not easily implemented and have several limitations. Therefore, it is of interest to explore Bayesian alternatives which provide the needed decision support to finalize a SAP. Methods We focus on generalized linear mixed models (GLMMs) for the analysis of longitudinal count data. A series of distributions with over- and under-dispersion is considered. Additionally, the structure of the variance components is modified. We perform a simulation study to investigate the discriminatory power of Bayesian tools for model criticism in different scenarios derived from the model setting. We apply the findings to the data from an open clinical trial on vertigo attacks. These data are seen as pilot data for an ongoing phase III trial. To fit GLMMs we use a novel Bayesian computational approach based on integrated nested Laplace approximations (INLAs). The INLA methodology enables the direct computation of leave-one-out predictive distributions. These distributions are crucial for Bayesian model assessment. We evaluate competing GLMMs for longitudinal count data according to the deviance information criterion (DIC) or probability integral transform (PIT), and by using proper scoring rules (e.g. the logarithmic score). Results The instruments under study provide excellent tools for preparing decisions within the SAP in a transparent way when structuring the primary analysis, sensitivity or ancillary analyses, and specific analyses for secondary endpoints. The mean logarithmic score and DIC discriminate well between different model scenarios. It becomes obvious that the naive choice of a conventional random effects Poisson model is often inappropriate for real-life count data. The findings are used to specify an appropriate mixed model employed in the sensitivity analyses of an ongoing phase III trial. Conclusions The proposed Bayesian methods are not only appealing for inference but notably provide a sophisticated insight into different aspects of model performance, such as forecast verification or calibration checks, and can be applied within the model selection process. The mean of the logarithmic score is a robust tool for model ranking and is not sensitive to sample size. Therefore, these Bayesian model selection techniques offer helpful decision support for shaping sensitivity and ancillary analyses in a statistical analysis plan of a clinical trial with longitudinal count data as the primary endpoint. PMID:22962944

Bayesian model selection techniques as decision support for shaping a statistical analysis plan of a clinical trial: an example from a vertigo phase III study with longitudinal count data as primary endpoint.

PubMed

Adrion, Christine; Mansmann, Ulrich

2012-09-10

A statistical analysis plan (SAP) is a critical link between how a clinical trial is conducted and the clinical study report. To secure objective study results, regulatory bodies expect that the SAP will meet requirements in pre-specifying inferential analyses and other important statistical techniques. To write a good SAP for model-based sensitivity and ancillary analyses involves non-trivial decisions on and justification of many aspects of the chosen setting. In particular, trials with longitudinal count data as primary endpoints pose challenges for model choice and model validation. In the random effects setting, frequentist strategies for model assessment and model diagnosis are complex and not easily implemented and have several limitations. Therefore, it is of interest to explore Bayesian alternatives which provide the needed decision support to finalize a SAP. We focus on generalized linear mixed models (GLMMs) for the analysis of longitudinal count data. A series of distributions with over- and under-dispersion is considered. Additionally, the structure of the variance components is modified. We perform a simulation study to investigate the discriminatory power of Bayesian tools for model criticism in different scenarios derived from the model setting. We apply the findings to the data from an open clinical trial on vertigo attacks. These data are seen as pilot data for an ongoing phase III trial. To fit GLMMs we use a novel Bayesian computational approach based on integrated nested Laplace approximations (INLAs). The INLA methodology enables the direct computation of leave-one-out predictive distributions. These distributions are crucial for Bayesian model assessment. We evaluate competing GLMMs for longitudinal count data according to the deviance information criterion (DIC) or probability integral transform (PIT), and by using proper scoring rules (e.g. the logarithmic score). The instruments under study provide excellent tools for preparing decisions within the SAP in a transparent way when structuring the primary analysis, sensitivity or ancillary analyses, and specific analyses for secondary endpoints. The mean logarithmic score and DIC discriminate well between different model scenarios. It becomes obvious that the naive choice of a conventional random effects Poisson model is often inappropriate for real-life count data. The findings are used to specify an appropriate mixed model employed in the sensitivity analyses of an ongoing phase III trial. The proposed Bayesian methods are not only appealing for inference but notably provide a sophisticated insight into different aspects of model performance, such as forecast verification or calibration checks, and can be applied within the model selection process. The mean of the logarithmic score is a robust tool for model ranking and is not sensitive to sample size. Therefore, these Bayesian model selection techniques offer helpful decision support for shaping sensitivity and ancillary analyses in a statistical analysis plan of a clinical trial with longitudinal count data as the primary endpoint.

Joint modelling of longitudinal CEA tumour marker progression and survival data on breast cancer

NASA Astrophysics Data System (ADS)

Borges, Ana; Sousa, Inês; Castro, Luis

2017-06-01

This work proposes the use of Biostatistics methods to study breast cancer in patients of Braga's Hospital Senology Unit, located in Portugal. The primary motivation is to contribute to the understanding of the progression of breast cancer, within the Portuguese population, using a more complex statistical model assumptions than the traditional analysis that take into account a possible existence of a serial correlation structure within a same subject observations. We aim to infer which risk factors aect the survival of Braga's Hospital patients, diagnosed with breast tumour. Whilst analysing risk factors that aect a tumour markers used on the surveillance of disease progression the Carcinoembryonic antigen (CEA). As survival and longitudinal processes may be associated, it is important to model these two processes together. Hence, a joint modelling of these two processes to infer on the association of these was conducted. A data set of 540 patients, along with 50 variables, was collected from medical records of the Hospital. A joint model approach was used to analyse these data. Two dierent joint models were applied to the same data set, with dierent parameterizations which give dierent interpretations to model parameters. These were used by convenience as the ones implemented in R software. Results from the two models were compared. Results from joint models, showed that the longitudinal CEA values were signicantly associated with the survival probability of these patients. A comparison between parameter estimates obtained in this analysis and previous independent survival[4] and longitudinal analysis[5][6], lead us to conclude that independent analysis brings up bias parameter estimates. Hence, an assumption of association between the two processes in a joint model of breast cancer data is necessary. Results indicate that the longitudinal progression of CEA is signicantly associated with the probability of survival of these patients. Hence, an assumption of association between the two processes in a joint model of breast cancer data is necessary.

Longitudinal Differences in the Low-latitude Ionosphere and in the Ionospheric Variability

NASA Astrophysics Data System (ADS)

Goncharenko, L. P.; Zhang, S.; Liu, H.; Tsugawa, T.; Batista, I. S.; Reinisch, B. W.

2017-12-01

Analysis of longitudinal differences in ionospheric parameters can illuminate variety of mechanisms responsible for ionospheric variability. In this study, we aim to 1) quantitatively describe major features of longitudinal differences in peak electron density in the low-latitude ionosphere; 2) examine differences in ionospheric variability at different longitude sectors, and 3) illustrate longitudinal differences in ionospheric response to a large disturbance event, sudden stratospheric warming of 2016. We examine NmF2 observations by a network of ionosondes in the American (30-80W) and Asian (110-170E) longitudinal sectors. Selected instruments are located in the vicinity of EIA troughs (Jicamarca, Sao Luis, Guam, Kwajalein), northern and southern crests of EIA (Boa Vista, Tucuman, Cachoeira Paulista, Okinawa), and beyond EIA crests (Ramey, Yamagawa, Kokubunji). To examine main ionospheric features at each location, we use long-term datasets collected at each site to construct empirical models that describe variations in NmF2 as a function of local time, season, solar flux, and geomagnetic activity. This set of empirical models can be used to accurately describe background ionospheric behavior and serve as a set of observational benchmarks for global circulation models. It reveals, for example, higher NmF2 in the EIA trough in the Asian sector as compared to the American sector. Further, we quantitatively describe variability in NmF2 as a difference between local observations and local empirical model, and find that American sector's EIA trough has overall higher variability that maximizes for all local times during wintertime, while Asian sector trough variability does not change significantly with season. Additionally, local empirical models are used to isolate ionospheric features resulting from dynamical disturbances of different origin (e.g. geomagnetic storms, convective activity, sudden stratospheric warming events, etc.). We illustrate this approach with the case of sudden stratospheric warming of 2016.

Childhood stunting in relation to the pre- and postnatal environment during the first 2 years of life: The MAL-ED longitudinal birth cohort study

PubMed Central

2017-01-01

Background Stunting is the most prevalent manifestation of childhood malnutrition. To characterize factors that contribute to stunting in resource-poor settings, we studied a priori selected biological and social factors collected longitudinally in a cohort of newborns. Methods and findings We enrolled 1,868 children across 7 resource-poor settings in Bangladesh, Brazil, India, Nepal, Peru, South Africa, and Tanzania shortly after birth and followed them for 24 months between 2 November 2009 and 28 February 2014. We collected longitudinal anthropometry, sociodemographic factors, maternal-reported illnesses, and antibiotic use; child feeding practices; dietary intake starting at 9 months; and longitudinal blood, urine, and stool samples to investigate non-diarrheal enteropathogens, micronutrients, gut inflammation and permeability, and systemic inflammation. We categorized length-for-age Z-scores into 3 groups (not stunted, ≥−1; at risk, <−1 to −2; and stunted, <−2), and used multivariable ordinal logistic regression to model the cumulative odds of being in a lower length-for-age category (at risk or stunted). A total of 1,197 children with complete longitudinal data were available for analysis. The prevalence of having a length-for-age Z-score below −1 increased from 43% (range 37%–47% across sites) shortly after birth (mean 7.7 days post-delivery, range 0 to 17 days) to 74% (16%–96%) at 24 months. The prevalence of stunting increased 3-fold during this same time period. Factors that contributed to the odds of being in a lower length-for-age category at 24 months were lower enrollment weight-for-age (interquartile cumulative odds ratio = 1.82, 95% CI 1.49–2.23), shorter maternal height (2.38, 1.89–3.01), higher number of enteropathogens in non-diarrheal stools (1.36, 1.07–1.73), lower socioeconomic status (1.75, 1.20–2.55), and lower percent of energy from protein (1.39, 1.13–1.72). Site-specific analyses suggest that reported associations were similar across settings. While loss to follow-up and missing data are inevitable, some study sites had greater loss to follow-up and more missing data than others, which may limit the generalizability of the findings. Conclusions Neonatal and maternal factors were early determinants of lower length-for-age, and their contribution remained important throughout the first 24 months of life, whereas the average number of enteropathogens in non-diarrheal stools, socioeconomic status, and dietary intake became increasingly important contributors by 24 months relative to neonatal and maternal factors. PMID:29069076

Developmental Differences in Parenting Behavior: Comparing Adolescent, Emerging Adult, and Adult Mothers

ERIC Educational Resources Information Center

Lewin, Amy; Mitchell, Stephanie J.; Ronzio, Cynthia R.

2013-01-01

The nationally representative Early Childhood Longitudinal Study-Birth cohort data set was used to compare parenting behaviors of adolescent mothers (less than 19 years old), emerging adult mothers (19-25 years old), and adult mothers (greater than 25 years old) when their children were 2 years old. Regression models controlling for socioeconomic…

Mediating Role of Self-Determination Constructs in Explaining the Relationship between School Factors and Postschool Outcomes

ERIC Educational Resources Information Center

Shogren, Karrie A.; Garnier Villarreal, Mauricio; Lang, Kyle; Seo, Hyojeong

2017-01-01

Secondary data analysis using the National Longitudinal Transition Study-2 data set was conducted to examine the degree to which autonomy, psychological empowerment, and self-realization (3 of 4 essential characteristics of self-determination) play a mediating role in the relationship between school-based factors and postschool outcomes. The…

A Collaboratively Designed Child Mental Health Service Model: Multiple Family Groups for Urban Children with Conduct Difficulties

ERIC Educational Resources Information Center

McKay, Mary M.; Gopalan, Geetha; Franco, Lydia; Dean-Assael, Kara; Chacko, Anil; Jackson, Jerrold M.; Fuss, Ashley

2011-01-01

This article presents preliminary outcomes associated with an experimental, longitudinal study of a Multiple Family Group (MFG) service delivery approach set within 13 urban outpatient clinics serving children and their families living in inner-city, primarily African American and Latino communities. Specifically, this article focuses on parent…

Resources and Research Production in Higher Education: A Longitudinal Analysis of Chinese Universities, 2000-2010

ERIC Educational Resources Information Center

Zhang, Liang; Bao, Wei; Sun, Liang

2016-01-01

In this study we examined the resource-research relationship at China's research universities. The stochastic frontier production function was employed in analyses of a panel data set on a group of the most research-intensive universities in China from 2000 to 2010. Results suggested overall tight relationships between various resources (including…

Media Effects on Ethnic Identity among Linguistic Majorities and Minorities: A Longitudinal Study of a Bilingual Setting

ERIC Educational Resources Information Center

Clement, Richard; Baker, Susan C.; Josephson, Gordon; Noels, Kimberly A.

2005-01-01

Research on media effects has documented the media's influence on beliefs and behavior while cross-cultural psychology has documented the effects of the language used in communication on identification with the ingroup and the outgroup. Media usage in the outgroup language should, therefore, affect identification patterns. This research…

Parental Choice of Infant Feeding Behaviours in South West Sydney: A Preliminary Investigation

ERIC Educational Resources Information Center

Arora, A.; Gay, M.; Thirukumar, D.

2012-01-01

Objective: The purpose of this study was to test a research instrument that could possibly be used for longitudinal research on infant feeding and to report on the preliminary results from the data collected. Design: Mixed methods approach--cross-sectional survey and qualitative research. Setting: Mother-infant dyads in South West Sydney,…

Influences and Mediators of the Effect of Poverty on Young Adolescent Depressive Symptoms.

ERIC Educational Resources Information Center

Eamon, Mary Keegan

2002-01-01

Analyzed data from the mother-child data set of the National Longitudinal Survey of Youth for 898 young adolescents (10-12 years) to study the influences that explain the relations between poverty and depressive symptoms measured 2 years later. Findings show that youth depressive symptoms are multiply determined, and that poverty can adversely…

Differential Effects of Home and Preschool Learning Environments on Early Language Development

ERIC Educational Resources Information Center

Schmerse, Daniel; Anders, Yvonne; Flöter, Manja; Wieduwilt, Nadine; Roßbach, Hans-Günther; Tietze, Wolfgang

2018-01-01

The present study is based on longitudinal data from a German early childhood education and care (ECEC) governmental initiative assessing children's grammatical and vocabulary development between 2;6 and 4;0 years (N = 1,331), quality of the home learning environment and quality of the preschool setting. Results showed that the quality of the home…

Patterns and Correlates of Substance Use among Affluent, Suburban High School Students

ERIC Educational Resources Information Center

McMahon, Thomas J.; Luthar, Suniya S.

2006-01-01

Despite ongoing concern about substance use during adolescence, very little is known about alcohol and drug use among teens living in affluent social settings. In this longitudinal study, cluster analysis was used to characterize patterns of substance use and change in other dimensions of psychosocial adjustment within a cohort of 292 high school…

The Life Course in the Making: Gender and the Development of Adolescents' Expected Timing of Adult Role Transitions

ERIC Educational Resources Information Center

Crockett, Lisa J.; Beal, Sarah J.

2012-01-01

Adolescents' expectations about the timing of adult role transitions have the potential to shape their actual transitions, setting the stage for their adult lives. Although expectations about timing emerge by early adolescence, little is known about how these expectations develop across adolescence. This longitudinal study examined developmental…

Understanding the Co-construction of Inquiry Practices: A Case Study of a Responsive Teaching Environment

ERIC Educational Resources Information Center

Maskiewicz, April C.; Winters, Victoria A.

2012-01-01

We set out to understand how different instantiations of inquiry emerged in two different years of one elementary teacher's classroom. Longitudinal observations from Mrs. Charles' 5th grade science classroom forced us to carefully and deliberately consider who exactly was responsible for the change in the class activities and norms. We provide…

Effects of School-Based Point-of-Testing Counselling on Health Status Variables among Rural Adolescents

ERIC Educational Resources Information Center

Murimi, Mary W.; Chrisman, Matthew S.; Hughes, Kelly; Taylor, Chris; Kim, Yeonsoo; McAllister, Tiffany L.

2015-01-01

Objective: Rural areas may suffer from a lack of access to health care and programmes to promote behaviours such as healthy eating and physical activity. Point-of-testing counselling is a method of promoting a healthy lifestyle during an individual's most "teachable moment". Design/Setting: This longitudinal study examined the effects of…

Morbid Obesity and the Transition from Welfare to Work

ERIC Educational Resources Information Center

Cawley, John; Danziger, Sheldon

2005-01-01

This paper utilizes a rich longitudinal data set--the Women's Employment Study (WES)--to investigate whether obesity, which is common among women of low socioeconomic status, is a barrier to employment and earnings for current and former welfare recipients. We find that former welfare recipients who are both White and morbidly obese have been less…

The Outdoor Recess Activities of Children at an Urban School: Longitudinal and Intraperiod Patterns

ERIC Educational Resources Information Center

Holmes, Robyn M.

2012-01-01

Based on a study of 149 parochial-school students enrolled in kindergarten through eighth grade, this article explores children's outdoor recess activities in an urban setting--with a focus on how age, gender, and size of play group influence their outdoor play preferences--and examines changes in children's activity preferences over a single…

Beginning Subbaccalaureate Students' Labor Market Experiences: Six Years Later in 2009. Web Tables. NCES 2012-273

ERIC Educational Resources Information Center

Ifill, Nicole; Radford, Alexandria Walton

2012-01-01

This set of Web Tables presents descriptive statistics on the spring 2009 labor market experiences of subbaccalaureate students who first entered postsecondary education in 2003-04. The Web Tables use data from the nationally representative 2004/09 Beginning Post-secondary Students Longitudinal Study (BPS:04/09), which followed a cohort of…

Examining ECLS-B: Maternal Stress and Depressive Symptoms when Raising Children with ASD

ERIC Educational Resources Information Center

Jeans, Laurie M.; Santos, Rosa Milagros; Laxman, Daniel J.; McBride, Brent A.; Dyer, W. Justin

2013-01-01

Using the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B), a nationally representative data set, we examined the extent to which mothers of preschool children with and without the diagnosis of an Autism Spectrum Disorder (ASD) reported stress and depressive symptoms prior to and following diagnosis of ASD. At 4 years, approximately 100…

Beyond Quantitative Decline: Conceptual Shifts in Adolescents' Development of Interest in Mathematics

ERIC Educational Resources Information Center

Frenzel, Anne C.; Pekrun, Reinhard; Dicke, Anna-Lena; Goetz, Thomas

2012-01-01

Research has shown that the average values for academic interest decrease during adolescence. Looking beyond such quantitative decline, we explored qualitative change of interest in the domain of mathematics across adolescence. Study 1 was based on a longitudinal data set (annual assessments from Grade 5 to Grade 9; N = 3,193). Latent variable…

Estimating Survival Rates in Engineering for Community College Transfer Students Using Grades in Calculus and Physics

ERIC Educational Resources Information Center

Laugerman, Marcia; Shelley, Mack; Rover, Diane; Mickelson, Steve

2015-01-01

This study uses a unique synthesized set of data for community college students transferring to engineering by combining several cohorts of longitudinal data along with transcript-level data, from both the Community College and the University, to measure success rates in engineering. The success rates are calculated by developing Kaplan-Meier…

Consequences of Empowered CNA Teams in Nursing Home Settings: A Longitudinal Assessment

ERIC Educational Resources Information Center

Yeatts, Dale E.; Cready, Cynthia M.

2007-01-01

Purpose: Recent studies have concluded that there is a lack of "patient-centered" care in nursing homes and subsequently a need for nursing home culture change. As a result, a variety of new, promising initiatives have been introduced, with most of these incorporating the use of "empowered" employees. The purpose of this study…

The Relationship between Basic Skills and Operational Effectiveness in the British Army

ERIC Educational Resources Information Center

Swain, Jon

2015-01-01

This paper draws on data that formed part of a major three-year longitudinal study (2008-2011), which set out to investigate basic skills (BS) provision and needs in the British army and its relationship to operational effectiveness. Using mixed methods, the findings draw on qualitative data from 60 semi-structured interviews with 26 young…

Childhood Cognitive Ability, Education, and Personality Traits Predict Attainment in Adult Occupational Prestige over 17 Years

ERIC Educational Resources Information Center

Cheng, Helen; Furnham, Adrian

2012-01-01

This study explored a longitudinal data set of nearly 5000 adults examining the effects of childhood cognitive ability (measured at age 11), parental social class (measured at birth), and personality on current occupational prestige (all measured at age 50), taking account the effects of education and the previous occupational levels (both…

Children's Executive Function and High-Calorie, Low-Nutrient Food Intake: Mediating Effects of Child-Perceived Adult Fast Food Intake

ERIC Educational Resources Information Center

Tate, Eleanor B.; Unger, Jennifer B.; Chou, Chih-Ping; Spruijt-Metz, Donna; Pentz, Mary Ann; Riggs, Nathaniel R.

2015-01-01

Objective: This study tested the relationships among child executive function (EF), child-perceived parent fast food intake, and child self-reported subsequent consumption of high-calorie, low-nutrient (HCLN) food. Design: One year and 6-month longitudinal observation from a larger randomized controlled trial. Setting. Southern California…

Longitudinal Study: Efficacy of Online Technology Tools for Instructional Use

NASA Technical Reports Server (NTRS)

Uenking, Michael D.

2011-01-01

Studies show that the student population (secondary and post secondary) is becoming increasingly more technologically savvy. Use of the internet, computers, MP3 players, and other technologies along with online gaming has increased tremendously amongst this population such that it is creating an apparent paradigm shift in the learning modalities of these students. Instructors and facilitators of learning can no longer rely solely on traditional lecture-based lesson formals. In order to achieve student academic success and satisfaction and to increase student retention, instructors must embrace various technology tools that are available and employ them in their lessons. A longitudinal study (January 2009-June 2010) has been performed that encompasses the use of several technology tools in an instructional setting. The study provides further evidence that students not only like the tools that are being used, but prefer that these tools be used to help supplement and enhance instruction.

A Six-Year Longitudinal Study of Consumption of Pornographic Materials in Chinese Adolescents in Hong Kong.

PubMed

Shek, Daniel T L; Ma, Cecilia M S

2016-02-01

Using longitudinal data collected over 6 years, consumption of pornographic materials in adolescents in Hong Kong and the related demographic and psychosocial correlates were examined in this study. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: A longitudinal research design with 6 waves of data was used to examine consumption of pornographic materials in high school students. A total of 3291 high school students from 28 schools responded to the questionnaire at wave 1. Consumption of online pornography was higher than traditional pornography. There was an increase in consumption of pornographic materials in the high school years. Gender, family functioning, and positive youth development were related to the initial status of pornography consumption. Besides, gender, family intactness and positive youth development predicted rates of change in consumption of pornographic material over time. The present findings showed that gender, family functioning, and positive youth development are significant predictors for pornography consumption in Chinese adolescents. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Longitudinal Surveys of Australian Youth (LSAY): 1995 Cohort--User Guide. Data Elements B2: Education. Technical Report 49B2

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2009

2009-01-01

This technical paper contains information about the variables in the Longitudinal Surveys of Australian Youth (LSAY) Year 95 cohort data set. It groups each variable into data elements that identify common variables within and across waves. Information is provided about each data element, including its purpose, values, base populations and…

Longitudinal Surveys of Australian Youth (LSAY): 1995 Cohort--User Guide. Data Elements A: Demographics. Technical Report 49A

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2012

2012-01-01

This technical paper contains information about the variables in the LSAY (Longitudinal Surveys of Australian Youth) Y95 cohort data set. It groups each variable into data elements which identifies common variables within and across waves. Information is provided about each data element including its purpose, values, base populations and relevant…

Longitudinal Surveys of Australian Youth (LSAY): 1995 Cohort--User Guide. Data Elements C: Employment. Technical Report 49C

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2009

2009-01-01

This technical paper contains information about the variables in the Longitudinal Surveys of Australian Youth (LSAY) Year 95 cohort data set. It groups each variable into data elements that identify common variables within and across waves. Information is provided about each data element including its purpose, values, base populations and relevant…

Longitudinal Surveys of Australian Youth (LSAY): 1995 Cohort--User Guide. Data Elements D: Social. Technical Report 49D

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2009

2009-01-01

This technical paper contains information about the variables in the Longitudinal Surveys of Australian Youth (LSAY) Year 95 cohort data set. It groups each variable into data elements that identify common variables within and across waves. Information is provided about each data element including its purpose, values, base populations and relevant…

Longitudinal Surveys of Australian Youth (LSAY): 1998 Cohort--User Guide. Data Elements D: Social. Technical Report 53D

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2009

2009-01-01

This technical paper contains information about the variables in the Longitudinal Surveys of Australian Youth (LSAY) Year 1998 cohort data set. It groups each variable into data elements which identifies common variables within and across waves. Information is provided about each data element including its purpose, values, base populations and…

The use of supportive-educative and mutual goal-setting strategies to improve self-management for patients with heart failure.

PubMed

Kline, Kay Setter; Scott, Linda D; Britton, Agnes S

2007-09-01

This study examined the effects of 2 home healthcare nursing approaches--supportive-educative and mutual goal setting--on self-management for patients with heart failure. Both approaches are specifically related to participants' understanding of heart failure and self-efficacy in managing the condition. An experimental, longitudinal, repeated-measures design was used with a sample of 88 participants. Although no significant difference was demonstrated in participants' understanding of heart failure, the supportive-educative group showed a significantly increased self-efficacy in managing heart failure symptoms.

Impact of breastfeeding duration on age at menarche.

PubMed

Al-Sahab, Ban; Adair, Linda; Hamadeh, Mazen J; Ardern, Chris I; Tamim, Hala

2011-05-01

The study aims to assess the relation between breastfeeding duration and age at menarche. Analysis was based on a cohort of 994 Filipino girls born in 1983-1984 and followed up from infancy to adulthood by the Cebu Longitudinal Health and Nutrition Survey. The main outcome was self-reported age at menarche. Cox regression was used to investigate the relation between duration of exclusive and any breastfeeding with age at menarche with adjustment sequentially for specific sets of known socioeconomic, maternal, genetic, and prenatal confounders. The estimated median of age at menarche was 13.08 years. After adjustment for potential confounders of the association of breastfeeding with age at menarche, exclusive breastfeeding duration retained an independent and significant association with age at menarche. An increase in 1 month of exclusive breastfeeding decreases the hazard of attaining earlier menarche by 6% (hazard ratio = 0.94, 95% confidence interval: 0.90, 0.98). Any breastfeeding duration was not associated with age at menarche. Although this is the first longitudinal study that reveals a negative association between exclusive breastfeeding and early menarche, the relation is still elusive. Further longitudinal studies within different contexts are warranted to assess the generalizability of these findings.

Analysis of Self-Excited Combustion Instabilities Using Decomposition Techniques

DTIC Science & Technology

2016-07-05

are evaluated for the study of self-excited longitudinal combustion instabilities in laboratory-scaled single-element gas turbine and rocket...Air Force Base, California 93524 DOI: 10.2514/1.J054557 Proper orthogonal decomposition and dynamic mode decomposition are evaluated for the study of...instabilities. In addition, we also evaluate the capabilities of the methods to deal with data sets of different spatial extents and temporal resolution

Developing Effective Wording and Format Options for a Children's Nutrition Behavior Questionnaire for Mothers of Children in Kindergarten. Contractor and Cooperator Report No. 10

ERIC Educational Resources Information Center

US Department of Agriculture, 2005

2005-01-01

This study focuses on a set of eating habit questions proposed for inclusion in the U.S. Department of Education's Early Childhood Longitudinal Survey, Birth Cohort. The study assesses the wording and format of a series of questions for mothers of children in kindergarten and/or first grade regarding the child's food consumption habits. Most…

A comparison of multiple imputation methods for handling missing values in longitudinal data in the presence of a time-varying covariate with a non-linear association with time: a simulation study.

PubMed

De Silva, Anurika Priyanjali; Moreno-Betancur, Margarita; De Livera, Alysha Madhu; Lee, Katherine Jane; Simpson, Julie Anne

2017-07-25

Missing data is a common problem in epidemiological studies, and is particularly prominent in longitudinal data, which involve multiple waves of data collection. Traditional multiple imputation (MI) methods (fully conditional specification (FCS) and multivariate normal imputation (MVNI)) treat repeated measurements of the same time-dependent variable as just another 'distinct' variable for imputation and therefore do not make the most of the longitudinal structure of the data. Only a few studies have explored extensions to the standard approaches to account for the temporal structure of longitudinal data. One suggestion is the two-fold fully conditional specification (two-fold FCS) algorithm, which restricts the imputation of a time-dependent variable to time blocks where the imputation model includes measurements taken at the specified and adjacent times. To date, no study has investigated the performance of two-fold FCS and standard MI methods for handling missing data in a time-varying covariate with a non-linear trajectory over time - a commonly encountered scenario in epidemiological studies. We simulated 1000 datasets of 5000 individuals based on the Longitudinal Study of Australian Children (LSAC). Three missing data mechanisms: missing completely at random (MCAR), and a weak and a strong missing at random (MAR) scenarios were used to impose missingness on body mass index (BMI) for age z-scores; a continuous time-varying exposure variable with a non-linear trajectory over time. We evaluated the performance of FCS, MVNI, and two-fold FCS for handling up to 50% of missing data when assessing the association between childhood obesity and sleep problems. The standard two-fold FCS produced slightly more biased and less precise estimates than FCS and MVNI. We observed slight improvements in bias and precision when using a time window width of two for the two-fold FCS algorithm compared to the standard width of one. We recommend the use of FCS or MVNI in a similar longitudinal setting, and when encountering convergence issues due to a large number of time points or variables with missing values, the two-fold FCS with exploration of a suitable time window.

Fracture patterns in the Zagros fold-and-thrust belt, Kurdistan Region of Iraq

NASA Astrophysics Data System (ADS)

Reif, Daniel; Decker, Kurt; Grasemann, Bernhard; Peresson, Herwig

2012-11-01

Fracture data have been collected in the Kurdistan Region of Iraq, which is a poorly accessible and unexplored area of the Zagros. Pre to early folding NE-SW striking extensional fractures and NW-SE striking contractive elements represent the older set affecting the exposed multilayer of the area. These latter structures are early syn-folding and followed by folding-related mesostructural assemblages, which include elements striking parallel to the axial trend of major folds (longitudinal fractures). Bedding perpendicular joints and veins, and extensional faults belonging to this second fracture set are located in the outer arc of exposed anticlines, whilst longitudinal reverse faults locate in the inner arcs. Consistently, these elements are associated with syn-folding tangential longitudinal strain. The younger two sets are related to E-W extension and NNE-SSW to N-S shortening, frequently displaying reactivation of the older sets. The last shortening event, which is described along the entire Zagros Belt, probably relates with the onset of N-S compression induced by the northward movement of the Arabian plate relative to the Eurasian Plate. In comparison between the inferred palaeostrain directions and the kinematics of recent GPS measurements, we conclude that the N-S compression and the partitioning into NW-SE trending folds and NW to N trending strike-slip faults likely remained unchanged throughout the Neogene tectonic history of the investigated area.

Modeling Pathways of Character Development across the First Three Decades of Life: An Application of Integrative Data Analysis Techniques to Understanding the Development of Hopeful Future Expectations.

PubMed

Callina, Kristina Schmid; Johnson, Sara K; Tirrell, Jonathan M; Batanova, Milena; Weiner, Michelle B; Lerner, Richard M

2017-06-01

There were two purposes of the present research: first, to add to scholarship about a key character virtue, hopeful future expectations; and second, to demonstrate a recent innovation in longitudinal methodology that may be especially useful in enhancing the understanding of the developmental course of hopeful future expectations and other character virtues that have been the focus of recent scholarship in youth development. Burgeoning interest in character development has led to a proliferation of short-term, longitudinal studies on character. These data sets are sometimes limited in their ability to model character development trajectories due to low power or relatively brief time spans assessed. However, the integrative data analysis approach allows researchers to pool raw data across studies in order to fit one model to an aggregated data set. The purpose of this article is to demonstrate the promises and challenges of this new tool for modeling character development. We used data from four studies evaluating youth character strengths in different settings to fit latent growth curve models of hopeful future expectations from participants aged 7 through 26 years. We describe the analytic strategy for pooling the data and modeling the growth curves. Implications for future research are discussed in regard to the advantages of integrative data analysis. Finally, we discuss issues researchers should consider when applying these techniques in their own work.

Estimating gestational age at birth from fundal height and additional anthropometrics: a prospective cohort study.

PubMed

Pugh, S J; Ortega-Villa, A M; Grobman, W; Newman, R B; Owen, J; Wing, D A; Albert, P S; Grantz, K L

2018-02-23

Accurate assessment of gestational age (GA) is critical to paediatric care, but is limited in developing countries without access to ultrasound. Our objectives were to assess the accuracy of prediction of GA at birth and preterm birth classification using routinely collected anthropometry measures. Prospective cohort study. United States. A total of 2334 non-obese and 468 obese pregnant women. Enrolment GA was determined based on last menstrual period, confirmed by first-trimester ultrasound. Maternal anthropometry and fundal height (FH) were measured by a standardised protocol at study visits; FH alone was additionally abstracted from medical charts. Neonatal anthropometry measurements were obtained at birth. To estimate GA at delivery, we developed three predictor models using longitudinal FH alone and with maternal and neonatal anthropometry. For all predictors, we repeatedly sampled observations to construct training (60%) and test (40%) sets. Linear mixed models incorporated longitudinal maternal anthropometry and a shared parameter model incorporated neonatal anthropometry. We assessed models' accuracy under varied scenarios. Estimated GA at delivery. Prediction error for various combinations of anthropometric measures ranged between 13.9 and 14.9 days. Longitudinal FH alone predicted GA within 14.9 days with relatively stable prediction errors across individual race/ethnicities [whites (13.9 days), blacks (15.1 days), Hispanics (15.5 days) and Asians (13.1 days)], and correctly identified 75% of preterm births. The model was robust to additional scenarios. In low-risk, non-obese women, longitudinal FH measures alone can provide a reasonably accurate assessment of GA when ultrasound measures are not available. Longitudinal fundal height alone predicts gestational age at birth when ultrasound measures are unavailable. © 2018 Royal College of Obstetricians and Gynaecologists.

Multivariate Longitudinal Analysis with Bivariate Correlation Test

PubMed Central

Adjakossa, Eric Houngla; Sadissou, Ibrahim; Hounkonnou, Mahouton Norbert; Nuel, Gregory

2016-01-01

In the context of multivariate multilevel data analysis, this paper focuses on the multivariate linear mixed-effects model, including all the correlations between the random effects when the dimensional residual terms are assumed uncorrelated. Using the EM algorithm, we suggest more general expressions of the model’s parameters estimators. These estimators can be used in the framework of the multivariate longitudinal data analysis as well as in the more general context of the analysis of multivariate multilevel data. By using a likelihood ratio test, we test the significance of the correlations between the random effects of two dependent variables of the model, in order to investigate whether or not it is useful to model these dependent variables jointly. Simulation studies are done to assess both the parameter recovery performance of the EM estimators and the power of the test. Using two empirical data sets which are of longitudinal multivariate type and multivariate multilevel type, respectively, the usefulness of the test is illustrated. PMID:27537692

Multivariate Longitudinal Analysis with Bivariate Correlation Test.

PubMed

Adjakossa, Eric Houngla; Sadissou, Ibrahim; Hounkonnou, Mahouton Norbert; Nuel, Gregory

2016-01-01

In the context of multivariate multilevel data analysis, this paper focuses on the multivariate linear mixed-effects model, including all the correlations between the random effects when the dimensional residual terms are assumed uncorrelated. Using the EM algorithm, we suggest more general expressions of the model's parameters estimators. These estimators can be used in the framework of the multivariate longitudinal data analysis as well as in the more general context of the analysis of multivariate multilevel data. By using a likelihood ratio test, we test the significance of the correlations between the random effects of two dependent variables of the model, in order to investigate whether or not it is useful to model these dependent variables jointly. Simulation studies are done to assess both the parameter recovery performance of the EM estimators and the power of the test. Using two empirical data sets which are of longitudinal multivariate type and multivariate multilevel type, respectively, the usefulness of the test is illustrated.

High-resolution three-dimensional 19F-magnetic resonance imaging of rat lung in situ: evaluation of airway strain in the perfluorocarbon-filled lung.

PubMed

Weigel, Julia K; Steinmann, Daniel; Emerich, Philipp; Stahl, Claudius A; v Elverfeldt, Dominik; Guttmann, Josef

2011-02-01

Perfluorocarbons (PFC) are biologically and chemically inert fluids with high oxygen and CO(2) carrying capacities. Their use as liquid intrapulmonary gas carriers during liquid ventilation has been investigated. We established a method of high resolution 3D-(19)F-MRI of the totally PFC-filled lung. The goal of this study was to investigate longitudinal and circumferential airway strain in the setting of increasing airway pressures on 3D-(19)F-MR images of the PFC-filled lung. Sixteen female Wistar rats were euthanized and the liquid perfluorocarbon FC-84 instilled into their lungs. 3D-(19)F-MRI was performed at various intrapulmonary pressures. Measurements of bronchial length and cross-sectional area were obtained from transversal 2D images for each pressure range. Changes in bronchial area were used to determine circumferential strain, while longitudinal strain was calculated from changes in bronchial length. Our method of 3D-(19)F-MRI allowed clear visualization of the great bronchi. Longitudinal strain increased significantly up to 31.1 cmH(2)O. The greatest strain could be found in the range of low airway pressures. Circumferential strain increased strongly with the initial pressure rise, but showed no significant changes above 10.4 cmH(2)O. Longitudinal strain was generally higher in distal airways, while circumferential strain showed no difference. Analysis of mechanical characteristics showed that longitudinal and circumferential airway expansion occurred in an anisotropic fashion. Whereas longitudinal strain still increased with higher pressures, circumferential strain quickly reached a 'strain limit'. Longitudinal strain was higher in distal bronchi, as dense PFCs gravitate to dependent, in this case to dorso-basal parts of the lung, acting as liquid positive end expiratory pressure.

A longitudinal study of paternal mental health during transition to fatherhood as young adults.

PubMed

Garfield, Craig F; Duncan, Greg; Rutsohn, Joshua; McDade, Thomas W; Adam, Emma K; Coley, Rebekah Levine; Chase-Lansdale, P Lindsay

2014-05-01

Rates of paternal depression range from 5% to 10% with a growing body of literature describing the harm to fathers, children, and families. Changes in depression symptoms over the life course, and the role of social factors, are not well known. This study examines associations with changes in depression symptoms during the transition to fatherhood for young fathers and whether this association differed by key social factors. We combined all 4 waves of the National Longitudinal Study of Adolescent Health to support a 23-year longitudinal analysis of 10 623 men and then created a "fatherhood-year" data set, regressing age-adjusted standardized depressive symptoms scores on fatherhood status (nonresidence/residence), fatherhood-years, and covariates to determine associations between Center for Epidemiologic Studies Depression Scale scores and fatherhood life course intervals. Depressive symptom scores reported at the entry into fatherhood are higher for nonresident fathers than nonfathers, which in turn are higher than those of resident fathers. Resident fathers have a significant decrease in scores during late adolescence (β = -0.035, P = .023), but a significant increase in scores during early fatherhood (β = 0.023, P = .041). From entrance into fatherhood to the end of early fatherhood (+5 years), the depressive symptoms score for resident fathers increases on average by 68%. In our longitudinal, population-based study, resident fathers show increasing depressive symptom scores during children's key attachment years of 0-5. Identifying at-risk fathers based on social factors and designing effective interventions may ultimately improve health outcomes for the entire family. Copyright © 2014 by the American Academy of Pediatrics.

Longitudinal multiple imputation approaches for body mass index or other variables with very low individual-level variability: the mibmi command in Stata.

PubMed

Kontopantelis, Evangelos; Parisi, Rosa; Springate, David A; Reeves, David

2017-01-13

In modern health care systems, the computerization of all aspects of clinical care has led to the development of large data repositories. For example, in the UK, large primary care databases hold millions of electronic medical records, with detailed information on diagnoses, treatments, outcomes and consultations. Careful analyses of these observational datasets of routinely collected data can complement evidence from clinical trials or even answer research questions that cannot been addressed in an experimental setting. However, 'missingness' is a common problem for routinely collected data, especially for biological parameters over time. Absence of complete data for the whole of a individual's study period is a potential bias risk and standard complete-case approaches may lead to biased estimates. However, the structure of the data values makes standard cross-sectional multiple-imputation approaches unsuitable. In this paper we propose and evaluate mibmi, a new command for cleaning and imputing longitudinal body mass index data. The regression-based data cleaning aspects of the algorithm can be useful when researchers analyze messy longitudinal data. Although the multiple imputation algorithm is computationally expensive, it performed similarly or even better to existing alternatives, when interpolating observations. The mibmi algorithm can be a useful tool for analyzing longitudinal body mass index data, or other longitudinal data with very low individual-level variability.

Dieting and disordered eating behaviors from adolescence to young adulthood: Findings from a 10-year longitudinal study

PubMed Central

Neumark-Sztainer, Dianne; Wall, Melanie; Larson, Nicole I.; Eisenberg, Marla E.; Loth, Katie

2011-01-01

Background Disordered eating behaviors are prevalent in adolescence and can have harmful consequences. An important question is whether use of these behaviors in adolescence sets the pattern for continued use into young adulthood. Objective To examine the prevalence and tracking of dieting, unhealthy and extreme weight control behaviors, and binge eating from adolescence to young adulthood. Design Population-based, 10-year longitudinal study (Project EAT-III: Eating Among Teens and Young Adults, 1999–2010). Participants/setting The study population includes 2,287 young adults (55% female, 52% non-white). The sample includes a younger group (mean age = 12.8±0.7 years at baseline and 23.2±1.0 years at follow-up) and an older group (mean age = 15.9±0.8 at baseline and 26.2±0.9 years at follow-up). Statistical analyses performed Longitudinal trends in prevalence of behaviors were tested using generalized estimating equations. Tracking of behaviors were estimated using the relative risk of behaviors at follow-up given presence at baseline. Results In general, the prevalence of dieting and disordered eating was high and remained constant, or increased, from adolescence to young adulthood. Furthermore, behaviors tended to track within individuals and, in general, participants who engaged in dieting and disordered eating behaviors during adolescence were at increased risk for these behaviors ten years later. Tracking was particularly consistent for the older females and males transitioning from middle adolescence to middle young adulthood. Conclusions Study findings indicate that disordered eating behaviors are not just an adolescent problem, but continue to be prevalent among young adults. The tracking of dieting and disordered eating within individuals suggests that early use is likely to set the stage for ongoing use. Findings suggest a need for both early prevention efforts prior to the onset of harmful behavioral patterns, as well as ongoing prevention and treatment interventions to address the high prevalence of disordered eating throughout adolescence and young adulthood. PMID:21703378

Longitudinal Surveys of Australian Youth (LSAY): 1995 Cohort--User Guide. Data Elements B1: Education. Technical Report 49B1

ERIC Educational Resources Information Center

National Centre for Vocational Education Research (NCVER), 2009

2009-01-01

This technical paper contains information about the variables in the LSAY (Longitudinal Surveys of Australian Youth) Y95 cohort data set. It groups each variable into data elements which identifies common variables within and across waves. Information is provided about each data element including its purpose, values, base populations and relevant.…

Situational Effects May Account for Gain Scores in Cognitive Ability Testing: A Longitudinal SEM Approach

ERIC Educational Resources Information Center

Matton, Nadine; Vautier, Stephane; Raufaste, Eric

2009-01-01

Mean gain scores for cognitive ability tests between two sessions in a selection setting are now a robust finding, yet not fully understood. Many authors do not attribute such gain scores to an increase in the target abilities. Our approach consists of testing a longitudinal SEM model suitable to this view. We propose to model the scores' changes…

Growing Our Own: A Longitudinal Evaluation of a Professional Development Program for Early-Career 4-H Professionals

ERIC Educational Resources Information Center

Varrella, Gary F.; Luckey, Brian P.; Baca, Jacqueline S.; Peters, Curt

2016-01-01

We present the results of a longitudinal evaluation of the Western Region 4-H Institute, a 5-day training program designed to enhance the skill sets of early-career Extension professionals organized around the 4-H professional research, knowledge, and competencies model. Programs such as this often are assessed for their short-term relevance and…

Quality of life of residents with dementia in long-term care settings in the Netherlands and Belgium: design of a longitudinal comparative study in traditional nursing homes and small-scale living facilities

PubMed Central

2011-01-01

Background The increase in the number of people with dementia will lead to greater demand for residential care. Currently, large nursing homes are trying to transform their traditional care for residents with dementia to a more home-like approach, by developing small-scale living facilities. It is often assumed that small-scale living will improve the quality of life of residents with dementia. However, little scientific evidence is currently available to test this. The following research question is addressed in this study: Which (combination of) changes in elements affects (different dimensions of) the quality of life of elderly residents with dementia in long-term care settings over the course of one year? Methods/design A longitudinal comparative study in traditional and small-scale long-term care settings, which follows a quasi-experimental design, will be carried out in Belgium and the Netherlands. To answer the research question, a model has been developed which incorporates relevant elements influencing quality of life in long-term care settings. Validated instruments will be used to evaluate the role of these elements, divided into environmental characteristics (country, type of ward, group size and nursing staff); basic personal characteristics (age, sex, cognitive decline, weight and activities of daily living); behavioural characteristics (behavioural problems and depression); behavioural interventions (use of restraints and use of psychotropic medication); and social interaction (social engagement and visiting frequency of relatives). The main outcome measure for residents in the model is quality of life. Data are collected at baseline, after six and twelve months, from residents living in either small-scale or traditional care settings. Discussion The results of this study will provide an insight into the determinants of quality of life for people with dementia living in traditional and small-scale long-term care settings in Belgium and the Netherlands. Possible relevant strengths and weaknesses of the study are discussed in this article. Trial registration ISRCTN: ISRCTN23772945 PMID:21539731

Development of Search Behavior Through Visual Representation in Infancy. RIEEC Research Bulletin RRB-11.

ERIC Educational Resources Information Center

Shimada, Shoko; And Others

The purpose of this study was to cross-sectionally and longitudinally examine the developmental process of search behavior in infancy. Subjects were 23 Japanese normal infants (11 males and 12 females) who were individually tested once a month from the age of six to 13 months in laboratory settings. Small toys and three white opaque cubic boxes…

Predicting the Influence of Demographic Differences and Schooling Experience in Adolescence on Occupational Choice in Adulthood

ERIC Educational Resources Information Center

Fletcher, Edward C., Jr.

2012-01-01

The purpose of this study was to predict occupational choices based on demographic variables and high school curriculum tracks. Based on an analysis of the 1997 National Longitudinal Survey of Youth (NLSY) data set that examined high school graduates' occupational choices in 2006, findings indicated that CTE graduates were 2.7 times more likely to…

Maternal Influences on Asian American-Pacific Islander Adolescents' Perceived Maternal Sexual Expectations and Their Sexual Initiation

ERIC Educational Resources Information Center

Kao, Tsui-Sui Annie; Loveland-Cherry, Carol; Guthrie, Barbara

2010-01-01

Maternal influences on adolescents' sexual initiation have been examined over two time points in 433 Asian American-Pacific Islander (AAPI) adolescents in a secondary analysis of the Add Health data set using structural equation modeling. A longitudinal model built on a preliminary qualitative study is used to examine the fit between data and…

Revisiting the Relationship between International Assessment Outcomes and Educational Production: Evidence From a Longitudinal PISA-TIMSS Sample

ERIC Educational Resources Information Center

Carnoy, Martin; Khavenson, Tatiana; Loyalka, Prashant; Schmidt, William H.; Zakharov, Andrey

2016-01-01

International assessments, such as the Program for International Student Assessment (PISA), are being used to recommend educational policies to improve student achievement. This study shows that the cross-sectional estimates behind such recommendations may be biased. We use a unique data set from one country that applied the PISA mathematics test…

Brief Training of HIV Medical Providers Increases Their Frequency of Delivering Prevention Counselling to Patients at Risk of Transmitting HIV to Others

ERIC Educational Resources Information Center

Patel, Shilpa N.; Marks, Gary; Gardner, Lytt; Golin, Carol E.; Shinde, Sanjyot; O'Daniels, Christine; Wilson, Tracey E.; Quinlivan, E. Byrd; Banderas, Julie W.

2013-01-01

Objective: The aim of this study was to examine whether brief training of human immunodeficiency virus (HIV) medical providers increased the frequency with which they routinely delivered prevention counselling to patients, and whether patient characteristics were associated with receipt of that counselling. Design: Longitudinal. Setting: Seven HIV…

Analysis of Person-Situation Interactions in Educational Settings via Cross-Classified Multilevel Longitudinal Modelling: Illustrated with the Example of Students' Stress Experience

ERIC Educational Resources Information Center

Kärner, Tobias; Sembill, Detlef; Aßmann, Christian; Friederichs, Edgar; Carstensen, Claus H.

2017-01-01

The investigation of learning processes by assessing students' experience along with objective characteristics within a classroom context has a long tradition in empirical learning process research (e.g. Sembill, 1984 et passim; Wild & Krapp, 1996). However, most of the existing studies confine themselves to psychological variables that seem…

Introducing a longitudinal study of community gardeners and gardens in New York City

Treesearch

Erika S. Svendsen; Lindsay K. Campbell; Nancy Falxa-Raymond; Jessica Northridge; Edie Stone

2012-01-01

For almost a decade, the NYC Department of Parks and Recreation GreenThumb program has collected data about hundreds of New York City community gardens citywide to understand how these gardens function. Building on a data set that includes surveys and interviews conducted periodically with garden representatives since 2003, GreenThumb and USDA Forest Service...

Understanding the Black-White Test Score Gap in the First Two Years of School. NBER Working Paper Series.

ERIC Educational Resources Information Center

Fryer, Roland G., Jr.; Levitt, Steven D.

In previous research, a substantial gap in test scores between white and black students persists, even after controlling for a wide range of observable characteristics. Using a data set made available by the National Center for Education Statistics, the Early Childhood Longitudinal Study, this paper demonstrates that in stark contrast to earlier…

Changing People, Consistent Experiences: 20 Years of Change and Stability at Grand Canyon National Park 1984-2004

ERIC Educational Resources Information Center

Backlund, Erik A.

2009-01-01

The purpose of this dissertation is to examine long term changes in the overnight backcountry hiker population at Grand Canyon National Park (GCNP) between 1984 and 2004. Longitudinal studies of visitor behavior in wildland recreation settings have been relatively rare but offer great potential for the improvement of management, clarification of…

Change Trajectories for the Youth Outcome Questionnaire Self-Report: Identifying Youth at Risk for Treatment Failure

ERIC Educational Resources Information Center

Cannon, Jennifer A. N.; Warren, Jared S.; Nelson, Philip L.; Burlingame, Gary M.

2010-01-01

This study used longitudinal youth outcome data in routine mental health services to test a system for identifying cases at risk for treatment failure. Participants were 2,715 youth (M age = 14) served in outpatient managed care and community mental health settings. Change trajectories were developed using multilevel modeling of archival data.…

Ethnic Identity and Gender as Moderators of the Association between Discrimination and Academic Adjustment among Mexican-Origin Adolescents

ERIC Educational Resources Information Center

Umana-Taylor, Adriana J.; Wong, Jessie J.; Gonzales, Nancy A.; Dumka, Larry E.

2012-01-01

Existing work has identified perceived discrimination as a risk factor that may contribute to the relatively poorer academic outcomes exhibited by Mexican-origin adolescents in the U.S. The current study examined the longitudinal associations among perceived discrimination and three indices of adolescent adjustment in the school setting (i.e.,…

The Role of Specialty Mental Health Care in Predicting Child Welfare and Juvenile Justice Out-of-Home Placements

ERIC Educational Resources Information Center

Glisson, Charles; Green, Philip

2006-01-01

Objective: This longitudinal, prospective study examines the role of specialty mental health care as provided by community-based, usual-care practice settings in predicting out-of-home placements among children served by a child welfare and juvenile justice system. Method: The mental health needs of 1,249 children from 22 counties in Tennessee…

Developmental Associations between Adolescent Change in Depressive Symptoms and Menstrual-Cycle-Phase-Specific Negative Affect during Early Adulthood

ERIC Educational Resources Information Center

Kiesner, Jeff; Poulin, Francois

2012-01-01

The causal factors associated with increases in depressive symptoms among adolescent girls remain an area of theoretical debate, and the limited research considering a hormonal influence has provided mixed results. The goal of the present study was to test a set of longitudinal associations, that, if found, would provide support for a hormonal…

Psychosocial Needs of Boys in Secure Care for Serious or Persistent Offending

ERIC Educational Resources Information Center

Harrington, R. C.; Kroll, L.; Rothwell, J.; McCarthy, K.; Bradley, D.; Bailey, S.

2005-01-01

Background: The mental health of child offenders who are detained in secure settings is a matter of great public and professional concern but there has been little systematic longitudinal research on the outcomes of these problems once the young person has returned to the community. The aims of the present study were to describe the psychosocial…

Predicting Nursing Home Admissions among Incontinent Older Adults: A Comparison of Residential Differences across Six Years.

ERIC Educational Resources Information Center

Coward, Raymond T.

1995-01-01

Uses data from the Longitudinal Studies on Aging (1984-90) to examine a sample who at baseline lived in community settings and reported problems with urinary incontinence (n=719). Analyses indicate that residents of less urbanized and more thinly populated nonmetropolitan counties were more likely to have a nursing home admission than others. (JPS)

Maternal Psychopathology and Infant Development at 18 Months: The Impact of Maternal Personality Disorder and Depression

ERIC Educational Resources Information Center

Conroy, Susan; Pariante, Carmine M.; Marks, Maureen N.; Davies, Helen A.; Farrelly, Simone; Schacht, Robin; Moran, Paul

2012-01-01

Objective: No previous longitudinal study has examined the impact of comorbid maternal personality disorder (PD) and depression on child development. We set out to examine whether maternal PD and depression assessed at 2 months post partum would be independently associated with adverse developmental outcomes at 18 months of age. Method: Women were…

Towards a High Quality High School Workforce: A Longitudinal, Demographic Analysis of U.S. Public School Physics Teachers

ERIC Educational Resources Information Center

Rushton, Gregory T.; Rosengrant, David; Dewar, Andrew; Shah, Lisa; Ray, Herman E.; Sheppard, Keith; Watanabe, Lynn

2017-01-01

Efforts to improve the number and quality of the high school physics teaching workforce have taken several forms, including those sponsored by professional organizations. Using a series of large-scale teacher demographic data sets from the National Center for Education Statistics (NCES), this study sought to investigate trends in teacher quality…

Students' Production of Curricular Knowledge: Perspectives on Empowerment in Financial Capability Education

ERIC Educational Resources Information Center

Farnsworth, Valerie; Davis, Pauline; Kalambouka, Afroditi; Ralph, Susan; Shi, Xin; Farrell, Peter

2011-01-01

The aim of this article is to extend our understanding of the relationship between knowledge of personal finance and empowerment. The analysis is based on interview data obtained as part of a longitudinal study of students, aged 16-19, who completed a financial capability course in the UK. The analysis presents a set of cultural models or…

Addressing Methodological Challenges in Large Communication Datasets: Collecting and Coding Longitudinal Interactions in Home Hospice Cancer Care

PubMed Central

Reblin, Maija; Clayton, Margaret F; John, Kevin K; Ellington, Lee

2015-01-01

In this paper, we present strategies for collecting and coding a large longitudinal communication dataset collected across multiple sites, consisting of over 2000 hours of digital audio recordings from approximately 300 families. We describe our methods within the context of implementing a large-scale study of communication during cancer home hospice nurse visits, but this procedure could be adapted to communication datasets across a wide variety of settings. This research is the first study designed to capture home hospice nurse-caregiver communication, a highly understudied location and type of communication event. We present a detailed example protocol encompassing data collection in the home environment, large-scale, multi-site secure data management, the development of theoretically-based communication coding, and strategies for preventing coder drift and ensuring reliability of analyses. Although each of these challenges have the potential to undermine the utility of the data, reliability between coders is often the only issue consistently reported and addressed in the literature. Overall, our approach demonstrates rigor and provides a “how-to” example for managing large, digitally-recorded data sets from collection through analysis. These strategies can inform other large-scale health communication research. PMID:26580414

Structural nested mean models for assessing time-varying effect moderation.

PubMed

Almirall, Daniel; Ten Have, Thomas; Murphy, Susan A

2010-03-01

This article considers the problem of assessing causal effect moderation in longitudinal settings in which treatment (or exposure) is time varying and so are the covariates said to moderate its effect. Intermediate causal effects that describe time-varying causal effects of treatment conditional on past covariate history are introduced and considered as part of Robins' structural nested mean model. Two estimators of the intermediate causal effects, and their standard errors, are presented and discussed: The first is a proposed two-stage regression estimator. The second is Robins' G-estimator. The results of a small simulation study that begins to shed light on the small versus large sample performance of the estimators, and on the bias-variance trade-off between the two estimators are presented. The methodology is illustrated using longitudinal data from a depression study.

Order-restricted inference for multivariate longitudinal data with applications to the natural history of hearing loss.

PubMed

Rosen, Sophia; Davidov, Ori

2012-07-20

Multivariate outcomes are often measured longitudinally. For example, in hearing loss studies, hearing thresholds for each subject are measured repeatedly over time at several frequencies. Thus, each patient is associated with a multivariate longitudinal outcome. The multivariate mixed-effects model is a useful tool for the analysis of such data. There are situations in which the parameters of the model are subject to some restrictions or constraints. For example, it is known that hearing thresholds, at every frequency, increase with age. Moreover, this age-related threshold elevation is monotone in frequency, that is, the higher the frequency, the higher, on average, is the rate of threshold elevation. This means that there is a natural ordering among the different frequencies in the rate of hearing loss. In practice, this amounts to imposing a set of constraints on the different frequencies' regression coefficients modeling the mean effect of time and age at entry to the study on hearing thresholds. The aforementioned constraints should be accounted for in the analysis. The result is a multivariate longitudinal model with restricted parameters. We propose estimation and testing procedures for such models. We show that ignoring the constraints may lead to misleading inferences regarding the direction and the magnitude of various effects. Moreover, simulations show that incorporating the constraints substantially improves the mean squared error of the estimates and the power of the tests. We used this methodology to analyze a real hearing loss study. Copyright © 2012 John Wiley & Sons, Ltd.

Longitudinal Associations of Neighborhood Collective Efficacy and Maternal Corporal Punishment with Behavior Problems in Early Childhood

PubMed Central

Ma, Julie; Grogan-Kaylor, Andrew

2017-01-01

Neighborhood and parenting influences on early behavioral outcomes are strongly dependent upon a child's stage of development. However, little research has jointly considered the longitudinal associations of neighborhood and parenting processes with behavior problems in early childhood. To address this limitation, this study explores the associations of neighborhood collective efficacy and maternal corporal punishment with the longitudinal patterns of early externalizing and internalizing behavior problems. The study sample consisted of 3,705 families from a nationally representative cohort study of urban families. Longitudinal multilevel models examined the associations of collective efficacy and corporal punishment with behavior problems at age 3, as well as with patterns of behavior problems between the ages 3 to 5. Interactions between the main predictors and child age tested whether neighborhood and parent relationships with child behavior varied over time. Mediation analysis examined whether neighborhood influences on child behavior were mediated by parenting. The models controlled for a comprehensive set of possible confounders at the child, parent, and neighborhood levels. Results indicate that both maternal corporal punishment and low neighborhood collective efficacy were significantly associated with increased behavior problems. The significant interaction between collective efficacy and child age with internalizing problems suggests that neighborhood influences on internalizing behavior were stronger for younger children. The indirect effect of low collective efficacy on behavior problems through corporal punishment was not significant. These findings highlight the importance of multilevel interventions that promote both neighborhood collective efficacy and non-physical discipline in early childhood. PMID:28425727

A modeling analysis program for the JPL table mountain Io sodium cloud

NASA Technical Reports Server (NTRS)

Smyth, W. H.; Goldberg, B. A.

1985-01-01

Progress and achievements in the first year are discussed in three main areas: (1) review and assessment of the massive JPL Table Mountain Io sodium cloud data set, (2) formulation and execution of a plan to perform further processing of this data set, and (3) initiation of modeling activities. The complete 1976-79 and 1981 data sets are reviewed. Particular emphasis is placed on the superior 1981 Region B/C images which provide a rich base of information for studying the structure and escape of gases from Io as well as possible east-west and magnetic longitudinal asymmetries in the plasma torus. A data processing plan is developed and is undertaken by the Multimission Image Processing Laboratory of JPL for the purpose of providing a more refined and complete data set for our modeling studies in the second year. Modeling priorities are formulated and initial progress in achieving these goals is reported.

A Military-Relevant Model of Closed Concussive Head Injury: Longitudinal Studies Characterizing and Validating Single and Repetitive mTBI

DTIC Science & Technology

2014-10-01

Research Program (CCCRP). Provided in this Year 2 Annual Report are the results of our Phase I studies focused on characterizing the neuropathologic...effects of a single concussive impact to repeated concussive impacts using the PCI model. Phase I studies have been completed and these results set...the foundation for Phase II studies designed to evaluate the effects of repeated concussions that occur prior to and after the resolution of the

Longitudinal Study of Reproductive Performance of Female Cattle Produced by Somatic Cell Nuclear Transfer

PubMed Central

Polejaeva, Irina A.; Broek, Diane M.; Walker, Shawn C.; Zhou, Wenli; Walton, Mark; Benninghoff, Abby D.; Faber, David C.

2013-01-01

The objective of this study was to determine whether or not reproductive performance in cattle produced by somatic cell nuclear transfer (SCNT) is significantly different from that of their genetic donors. To address this question, we directed two longitudinal studies using different embryo production procedures: (1) superovulation followed by artificial insemination (AI) and embryo collection and (2) ultrasound-guided ovum pick-up followed by in vitro fertilization (OPU-IVF). Collectively, these two studies represent the largest data set available for any species on the reproductive performance of female clones and their genetic donors as measured by their embryo production outcomes in commercial embryo production program. The large-scale study described herein was conducted over a six-year period of time and provides a unique comparison of 96 clones to the 40 corresponding genetic donors. To our knowledge, this is the first longitudinal study on the reproductive performance of cattle clones using OPU-IVF. With nearly 2,000 reproductive procedures performed and more than 9,200 transferable embryos produced, our observations show that the reproductive performance of cattle produced by SCNT is not different compared to their genetic donors for the production of transferable embryos after either AI followed by embryo collection (P = 0.77) or OPU-IVF (P = 0.97). These data are in agreement with previous reports showing that the reproductive capabilities of cloned cattle are equal to that of conventionally produced cattle. In conclusion, results of this longitudinal study once again demonstrate that cloning technology, in combination with superovulation, AI and embryo collection or OPU-IVF, provides a valuable tool for faster dissemination of superior maternal genetics. PMID:24391930

Longitudinal study of reproductive performance of female cattle produced by somatic cell nuclear transfer.

PubMed

Polejaeva, Irina A; Broek, Diane M; Walker, Shawn C; Zhou, Wenli; Walton, Mark; Benninghoff, Abby D; Faber, David C

2013-01-01

The objective of this study was to determine whether or not reproductive performance in cattle produced by somatic cell nuclear transfer (SCNT) is significantly different from that of their genetic donors. To address this question, we directed two longitudinal studies using different embryo production procedures: (1) superovulation followed by artificial insemination (AI) and embryo collection and (2) ultrasound-guided ovum pick-up followed by in vitro fertilization (OPU-IVF). Collectively, these two studies represent the largest data set available for any species on the reproductive performance of female clones and their genetic donors as measured by their embryo production outcomes in commercial embryo production program. The large-scale study described herein was conducted over a six-year period of time and provides a unique comparison of 96 clones to the 40 corresponding genetic donors. To our knowledge, this is the first longitudinal study on the reproductive performance of cattle clones using OPU-IVF. With nearly 2,000 reproductive procedures performed and more than 9,200 transferable embryos produced, our observations show that the reproductive performance of cattle produced by SCNT is not different compared to their genetic donors for the production of transferable embryos after either AI followed by embryo collection (P = 0.77) or OPU-IVF (P = 0.97). These data are in agreement with previous reports showing that the reproductive capabilities of cloned cattle are equal to that of conventionally produced cattle. In conclusion, results of this longitudinal study once again demonstrate that cloning technology, in combination with superovulation, AI and embryo collection or OPU-IVF, provides a valuable tool for faster dissemination of superior maternal genetics.

Electrical contact tool set station

DOEpatents

Byers, M.E.

1988-02-22

An apparatus is provided for the precise setting to zero of electrically conductive cutting tools used in the machining of work pieces. An electrically conductive cylindrical pin, tapered at one end to a small flat, rests in a vee-shaped channel in a base so that its longitudinal axis is parallel to the longitudinal axis of the machine's spindle. Electronic apparatus is connected between the cylindrical pin and the electrically conductive cutting tool to produce a detectable signal when contact between tool and pin is made. The axes of the machine are set to zero by contact between the cutting tool and the sides, end or top of the cylindrical pin. Upon contact, an electrical circuit is completed, and the detectable signal is produced. The tool can then be set to zero for that axis. Should the tool contact the cylindrical pin with too much force, the cylindrical pin would be harmlessly dislodged from the vee-shaped channel, preventing damage either to the cutting tool or the cylindrical pin. 5 figs.

A longitudinal comparative study of the physical and mental health problems of affected residents of the firework disaster Enschede, The Netherlands.

PubMed

Grievink, L; van der Velden, P G; Stellato, R K; Dusseldorp, A; Gersons, B P R; Kleber, R J; Lebret, E

2007-05-01

After the firework disaster in Enschede, The Netherlands, on 13 May 2000, a longitudinal health study was carried out. Study questions were: (1) did the health status change over this period; and (2) how is the health status 18 months after the disaster compared with controls? A longitudinal comparative study with two surveys at 3 weeks and 18 months after the disaster. A control group for the affected residents was included in the second survey. Respondents filled in a set of validated questionnaires measuring their physical and mental health problems. The prevalence of physical and emotional role limitations, severe sleeping problems, feelings of depression and anxiety, as well as intrusion and avoidance decreased from 3 weeks to 18 months after the disaster for the affected residents. Independent of background characteristics and other life events, residents had 1.5 to three times more health problems than the control group; for example, physical role limitations (odds ratio [OR]=1.5, 95% confidence interval [CI] 1.2-2.0) and anxiety (OR=3.1, 95% CI 2.4-4.2). Although health problems decreased compared with 3 weeks after the disaster, 18 months after the disaster, the affected residents had more health problems than the people from the control group.

Where Self-Control Comes from: On the Development of Self-Control and Its Relationship to Deviance over Time

ERIC Educational Resources Information Center

Vazsonyi, Alexander T.; Huang, Li

2010-01-01

The current study tested a set of interrelated theoretical propositions based on self-control theory (M. R. Gottfredson & T. Hirschi 1990). Data were collected on 1,155 children at 4.5 years, at 8.5 years (3rd grade), and at 10.5 years (5th grade) as part of the National Institute of Child Health and Human Development longitudinal study over a…

Changes in the Characteristics, Services, and Performance of Preschoolers with Disabilities from 2003-04 to 2004-05. Wave 2 Overview Report from the Pre-Elementary Education Longitudinal Study (PEELS). NCSER 2008-3011

ERIC Educational Resources Information Center

Carlson, Elaine; Daley, Tamara; Shimshak, Amy; Riley, Jarnee; Keller, Brad; Jenkins, Frank; Markowitz, Joy; Rosenquist, Celia

2008-01-01

PEELS involves a nationally representative sample of children, 3 to 5 years of age when they entered the study, with diverse disabilities who are receiving preschool special education services in a variety of settings. Topics covered in the report include declassification (children leaving special education), reclassification (movement from one…

Longitudinal Effects of Class Size Reductions on Attainment: Results from Hong Kong Primary Classrooms

ERIC Educational Resources Information Center

Galton, Maurice; Pell, Tony

2012-01-01

In a four-year study of the effect of class size on pupil outcomes in a sample of 36 primary schools in Hong Kong, it has been found that there are few positive differences in attainment between classes set at less than 25 pupils and those of normal size averaging 38. Three cohorts of pupils were studied. In Cohort 1 pupils spent 3 years in small…

Contribution of the maculo-ocular reflex to gaze stability in the rabbit.

PubMed

Pettorossi, V E; Errico, P; Santarelli, R M

1991-01-01

The contribution of the maculo-ocular reflex to gaze stability was studied in 10 pigmented rabbits by rolling the animals at various angles of sagittal inclination of the rotation and/or longitudinal animal axes. At low frequencies (0.005-0.01 Hz) of sinusoidal stimulation the vestibulo-ocular reflex (VOR) was due to macular activation, while at intermediate and high frequencies it was mainly due to ampullar activation. The following results were obtained: 1) maculo-ocular reflex gain decreased as a function of the cosine of the angle between the rotation axis and the earth's horizontal plane. No change in gain was observed when longitudinal animal axis alone was inclined. 2) At 0 degrees of rotation axis and with the animal's longitudinal axis inclination also set at 0 degrees, the maculo-ocular reflex was oriented about 20 degrees forward and upward with respect to the earth's vertical axis. This orientation remained constant with sagittal inclinations of the rotation and/or longitudinal animal axes ranging from approximately 5 degrees upward to 30 degrees downward. When the longitudinal animal axis was inclined beyond these limits, the eye trajectory tended to follow the axis inclination. In the upside down position, the maculo-ocular reflex was anticompensatory, oblique and fixed with respect to orbital coordinates. 3) Ampullo-ocular reflex gain did not change with inclinations of the rotation and/or longitudinal animal axes. The ocular responses were consistently oriented to the stimulus plane. At intermediate frequencies the eye movement trajectory was elliptic because of directional differences between the ampullo- and maculo-ocular reflexes.(ABSTRACT TRUNCATED AT 250 WORDS)

A retrospective, longitudinal study of factors associated with new antipsychotic medication use among recently admitted long-term care residents.

PubMed

Foebel, Andrea; Ballokova, Anna; Wellens, Nathalie I H; Fialova, Daniela; Milisen, Koen; Liperoti, Rosa; Hirdes, John P

2015-10-19

Use of antipsychotic (AP) medications is high and often inappropriate among institutionalized populations. Little is known about the correlates of new AP drug use following admission to long-term care (LTC) settings. This study investigated the frequency and correlates of new AP drug use among newly admitted LTC residents. This longitudinal, retrospective study used data from the interRAI - Nursing Home Minimum Data Set version 2.0 (MDS 2.0) instrument. Data about demographic, clinical and social characteristics, and medication use, were collected in Ontario, Canada, from 2003-2011 by trained nurses. Residents with complete admission and 3-6 month follow-up data were included (N = 47,768). Multivariate logistic regression analyses, stratified by gender, explored correlates of new AP drug use upon admission to LTC. New AP drug users comprised 7 % of the final cohort. Severe cognitive impairment, dementia, and motor agitation were significantly associated with new AP drug use among both sexes. Additionally, behavioural problems, conflicts with staff and reduced social engagement were strong correlates of new AP drug use. Social factors were as strongly associated with new AP drug use after LTC admission as clinical factors. Strategies to prevent the potential misuse of AP drugs upon LTC admission should consider the social determinants of such prescribing.

A typology of longitudinal integrated clerkships.

PubMed

Worley, Paul; Couper, Ian; Strasser, Roger; Graves, Lisa; Cummings, Beth-Ann; Woodman, Richard; Stagg, Pamela; Hirsh, David

2016-09-01

Longitudinal integrated clerkships (LICs) represent a model of the structural redesign of clinical education that is growing in the USA, Canada, Australia and South Africa. By contrast with time-limited traditional block rotations, medical students in LICs provide comprehensive care of patients and populations in continuing learning relationships over time and across disciplines and venues. The evidence base for LICs reveals transformational professional and workforce outcomes derived from a number of small institution-specific studies. This study is the first from an international collaborative formed to study the processes and outcomes of LICs across multiple institutions in different countries. It aims to establish a baseline reference typology to inform further research in this field. Data on all LIC and LIC-like programmes known to the members of the international Consortium of Longitudinal Integrated Clerkships were collected using a survey tool developed through a Delphi process and subsequently analysed. Data were collected from 54 programmes, 44 medical schools, seven countries and over 15 000 student-years of LIC-like curricula. Wide variation in programme length, student numbers, health care settings and principal supervision was found. Three distinct typological programme clusters were identified and named according to programme length and discipline coverage: Comprehensive LICs; Blended LICs, and LIC-like Amalgamative Clerkships. Two major approaches emerged in terms of the sizes of communities and types of clinical supervision. These referred to programmes based in smaller communities with mainly family physicians or general practitioners as clinical supervisors, and those in more urban settings in which subspecialists were more prevalent. Three distinct LIC clusters are classified. These provide a foundational reference point for future studies on the processes and outcomes of LICs. The study also exemplifies a collaborative approach to medical education research that focuses on typology rather than on individual programme or context. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Clinical Utility of SPECT Neuroimaging in the Diagnosis and Treatment of Traumatic Brain Injury: A Systematic Review

PubMed Central

Raji, Cyrus A.; Tarzwell, Robert; Pavel, Dan; Schneider, Howard; Uszler, Michael; Thornton, John; van Lierop, Muriel; Cohen, Phil; Amen, Daniel G.; Henderson, Theodore

2014-01-01

Purpose This systematic review evaluated the clinical utility of single photon emission computed tomography (SPECT) in traumatic brain injury (TBI). Methods After defining a PICO Statement (Population, Intervention, Comparison and Outcome Statement), PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria were applied to identify 1600 articles. After screening, 374 articles were eligible for review. Inclusion for review was focus on SPECT in the setting of mild, moderate, or severe TBI with cerebral lobar specificity of SPECT findings. Other inclusion criteria were comparison modalities in the same subjects and articles in English. Foreign language articles, SPECT studies that did not include comparison modalities, and case reports were not included for review. Results We identified 19 longitudinal and 52 cross-sectional studies meeting inclusion criteria. Three longitudinal studies examined diagnostic predictive value. The first showed positive predictive value increases from initial SPECT scan shortly after trauma to one year follow up scans, from 59% to 95%. Subsequent work replicated these results in a larger cohort. Longitudinal and cross sectional studies demonstrated SPECT lesion localization not detected by CT or MRI. The most commonly abnormal regions revealed by SPECT in cross-sectional studies were frontal (94%) and temporal (77%) lobes. SPECT was found to outperform both CT and MRI in both acute and chronic imaging of TBI, particularly mild TBI. It was also found to have a near 100% negative predictive value. Conclusions This review demonstrates Level IIA evidence (at least one non-randomized controlled trial) for the value of SPECT in TBI. Given its advantages over CT and MRI in the detection of mild TBI in numerous studies of adequate quality, and given its excellent negative predictive value, it may be an important second test in settings where CT or MRI are negative after a closed head injury with post-injury neurological or psychiatric symptoms. PMID:24646878

Clinical utility of SPECT neuroimaging in the diagnosis and treatment of traumatic brain injury: a systematic review.

PubMed

Raji, Cyrus A; Tarzwell, Robert; Pavel, Dan; Schneider, Howard; Uszler, Michael; Thornton, John; van Lierop, Muriel; Cohen, Phil; Amen, Daniel G; Henderson, Theodore

2014-01-01

This systematic review evaluated the clinical utility of single photon emission computed tomography (SPECT) in traumatic brain injury (TBI). After defining a PICO Statement (Population, Intervention, Comparison and Outcome Statement), PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria were applied to identify 1600 articles. After screening, 374 articles were eligible for review. Inclusion for review was focus on SPECT in the setting of mild, moderate, or severe TBI with cerebral lobar specificity of SPECT findings. Other inclusion criteria were comparison modalities in the same subjects and articles in English. Foreign language articles, SPECT studies that did not include comparison modalities, and case reports were not included for review. We identified 19 longitudinal and 52 cross-sectional studies meeting inclusion criteria. Three longitudinal studies examined diagnostic predictive value. The first showed positive predictive value increases from initial SPECT scan shortly after trauma to one year follow up scans, from 59% to 95%. Subsequent work replicated these results in a larger cohort. Longitudinal and cross sectional studies demonstrated SPECT lesion localization not detected by CT or MRI. The most commonly abnormal regions revealed by SPECT in cross-sectional studies were frontal (94%) and temporal (77%) lobes. SPECT was found to outperform both CT and MRI in both acute and chronic imaging of TBI, particularly mild TBI. It was also found to have a near 100% negative predictive value. This review demonstrates Level IIA evidence (at least one non-randomized controlled trial) for the value of SPECT in TBI. Given its advantages over CT and MRI in the detection of mild TBI in numerous studies of adequate quality, and given its excellent negative predictive value, it may be an important second test in settings where CT or MRI are negative after a closed head injury with post-injury neurological or psychiatric symptoms.

Riparian Land Use/Land Cover Data for Three Study Units in Group II of the Nutrient Enrichment Effects Topical Study of the National Water-Quality Assessment Program

USGS Publications Warehouse

Johnson, Michaela R.; Clark, Jimmy M.; Dickinson, Ross G.; Sanocki, Chris A.; Tranmer, Andrew W.

2009-01-01

This data set was developed as part of the National Water-Quality Assessment (NAWQA) Program, Nutrient Enrichment Effects Topical (NEET) study. This report is concerned with three of the eight NEET study units distributed across the United States: Ozark Plateaus, Upper Mississippi River Basin, and Upper Snake River Basin, collectively known as Group II of the NEET study. Ninety stream reaches were investigated during 2006-08 in these three study units. Stream segments, with lengths equal to the base-10 logarithm of the basin area, were delineated upstream from the stream reaches through the use of digital orthophoto quarter-quadrangle (DOQQ) imagery. The analysis area for each stream segment was defined by a streamside buffer extending laterally to 250 meters from the stream segment. Delineation of landuse and land-cover (LULC) map units within stream-segment buffers was completed using on-screen digitizing of riparian LULC classes interpreted from the DOQQ. LULC units were classified using a strategy consisting of nine classes. National Wetlands Inventory (NWI) data were used to aid in wetland classification. Longitudinal riparian transects (lines offset from the stream segments) were generated digitally, used to sample the LULC maps, and partitioned in accord with the intersected LULC map-unit types. These longitudinal samples yielded the relative linear extent and sequence of each LULC type within the riparian zone at the segment scale. The resulting areal and linear estimates of LULC extent filled in the spatial-scale gap between the 30-meter resolution of the 1990s National Land Cover Dataset and the reach-level habitat assessment data collected onsite routinely for NAWQA ecological sampling. The resulting data consisted of 12 geospatial data sets: LULC within 25 meters of the stream reach (polygon); LULC within 50 meters of the stream reach (polygon); LULC within 50 meters of the stream segment (polygon); LULC within 100 meters of the stream segment (polygon); LULC within 150 meters of the stream segment (polygon); LULC within 250 meters of the stream segment (polygon); frequency of gaps in woody vegetation at the reach scale (arc); stream reaches (arc); longitudinal LULC transect sample at the reach scale (arc); frequency of gaps in woody vegetation at the segment scale (arc); stream segments (arc); and longitudinal LULC transect sample at the segment scale (arc).

Impact of integrated upper limb spasticity management including botulinum toxin A on patient-centred goal attainment: rationale and protocol for an international prospective, longitudinal cohort study (ULIS-III)

PubMed Central

Turner-Stokes, Lynne; Ashford, Stephen; Jacinto, Jorge; Maisonobe, Pascal; Balcaitiene, Jovita; Fheodoroff, Klemens

2016-01-01

Objectives Describe the rationale and protocol for the Upper Limb International Spasticity (ULIS)-III study, which aims to evaluate the impact of integrated spasticity management, involving multiple botulinum toxin A (BoNT-A) injection cycles and concomitant therapies, on patient-centred goal attainment. Outline novel outcome assessment methods for ULIS-III and report initial evaluation data from goal setting in early stages of the study. Design Large international longitudinal cohort study of integrated upper limb spasticity management, including BoNT-A. Participants and setting ULIS-III is a 2-year study expected to enrol >1000 participants at 58 study centres across 14 countries. Interventions The study design is non-interventional and intended to reflect real-life clinical practice. It will describe injection practices and additional treatment strategies, and record clinical decision-making in a serial approach to long-term spasticity management. Outcome measures ULIS-III will use a goal-directed approach to selection of targeted standardised measures to capture the diversity of presentation, goals and outcomes. ULIS-III will implement the Upper Limb Spasticity Index, a battery of assessments including a structured approach to goal attainment scaling (Goal Attainment Scaling—Evaluation of Outcomes for Upper Limb Spasticity tool), alongside a limited set of standardised measures, chosen according to patients' selected goal areas. Concomitant therapy inputs, patient satisfaction with engagement in goal setting, health economic end points and health-related quality of life data will also be captured. Results of initial evaluation of goal quality Recruitment started in January 2015. By June 2015, 58 sites had been identified and initial data collected for 79 patients across 13 sites in 3 countries. Goal setting data were quality-checked and centres rated on the basis of function-related and Specific, Measurable, Achievable, Realistic, Timed (SMART) characteristics of goal statements. Overall, 11/13 centres achieved the highest rating (A++). Conclusions ULIS-III will provide valuable information regarding treatment of and outcomes from real-life upper limb spasticity management worldwide. Trial registration number NCT02454803; Pre-results. PMID:27315835

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

DeChant, Lawrence Justin; Smith, Justin A.

Here we discuss an improved Corcos (Corcos (1963), (1963)) style cross spectral density utilizing zero pressure gradient, supersonic (Beresh et. al. (2013)) data sets. Using the connection between narrow band measurements with broadband cross-spectral density, i.e. Γ(ξ ,η ,ω )= Φ (ω) A(ωη/U )exp (-i ωξ/U) we focus on estimating coherence expressions of the form: A (ξω nb/U) and B (ηω nb/ U) where ω nb denotes the narrow band frequency, i.e. the band center frequency value and ξ and η are sensors spacing in streamwise/longitudinal and cross-stream/lateral directions, respectively. A methodology to estimate the parameters which retains the Corcosmore » exponential functional form, A(ξω/U)=exp(-k lat ηω/U) but identifies new parameters (constants) consistent with the Beresh et. al. data sets is discussed. The Corcos result requires that the data be properly explained by self-similar variable: ξω/U and ηω/U. The longitudinal (streamwise) variable ξω/U tends to provide a better data collapse, while, consistent with the literature the lateral ηω/U is only successful for higher band center frequencies. Assuming the similarity variables provide a useful description of the data, the longitudinal coherence decay constant result using the Beresh et. al. data sets yields a value for the longitudinal constant k long≈0.36-0.28 that is approximately 3x larger than the “traditional” (low speed, large Reynolds number and zero pressure gradient) of k long≈0.11. We suggest that the most likely reason that the Beresh et. al. data sets incur increased longitudinal decay which results in reduced coherence lengths is due to wall shear induced compression causing an adverse pressure gradient. Focusing on the higher band center frequency measurements where the frequency dependent similarity variables are applicable, the lateral or transverse coherence decay constant k lat≈0.7 is consistent with the “traditional” (low speed, large Reynolds number and zero pressure gradient). It should be noted, that the longitudinal/streamwise coherence decay deviates from the value observed by other researchers while the lateral/ cross-stream value is consistent has been observed by other researchers. We believe that while the measurements used to obtain new decay constant estimates are from internal wind tunnel tests, they likely provide a useful estimate expected reentry flow behavior and are therefore recommended for use. These data could also be useful in determining the uncertainty of correlation length for a uncertainty quantification (UQ) analysis.« less

Longitudinal weight gain in women identified with polycystic ovary syndrome: results of an observational study in young women.

PubMed

Teede, Helena J; Joham, Anju E; Paul, Eldho; Moran, Lisa J; Loxton, Deborah; Jolley, Damien; Lombard, Catherine

2013-08-01

Polycystic ovary syndrome (PCOS) affects 6-18% of women. The natural history of weight gain in women with PCOS has not been well described. Here we aimed to examine longitudinal weight gain in women with and without PCOS and to assess the association between obesity and PCOS prevalence. The observational study was set in the general community. Participants were women randomly selected from the national health insurance scheme (Medicare) database. Mailed survey data were collected by the Australian Longitudinal Study on Women's Health. Data from respondents to survey 4, aged 28-33 years (2006, n = 9,145) were analyzed. The main outcome measures were PCOS prevalence and body mass index (BMI). Self-reported PCOS prevalence was 5.8% (95% CI: 5.3%-6.4%). Women reporting PCOS had higher weight, mean BMI [2.5 kg/m(2) (95% CI: 1.9-3.1)], and greater 10-year weight gain [2.6 kg (95% CI: 1.2-4.0)]. BMI was the strongest correlate of PCOS status with every BMI increment increasing the risk of reporting PCOS by 9.2% (95% CI: 6%-12%). This community based observational study with longitudinal reporting of weight shows that weight, BMI, and 10-year weight gain were higher in PCOS. We report the novel finding that obesity and greater weight gain are significantly associated with PCOS status. Considering the prevalence, major health and economic burden of PCOS, the increasing weight gain in young women, and established benefits of weight loss, these results have major public health implications. Copyright © 2012 The Obesity Society.

Parallel But Not Equivalent: Challenges and Solutions for Repeated Assessment of Cognition over Time

PubMed Central

Gross, Alden L.; Inouye, Sharon K.; Rebok, George W.; Brandt, Jason; Crane, Paul K.; Parisi, Jeanine M.; Tommet, Doug; Bandeen-Roche, Karen; Carlson, Michelle C.; Jones, Richard N.

2013-01-01

Objective Analyses of individual differences in change may be unintentionally biased when versions of a neuropsychological test used at different follow-ups are not of equivalent difficulty. This study’s objective was to compare mean, linear, and equipercentile equating methods and demonstrate their utility in longitudinal research. Study Design and Setting The Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE, N=1,401) study is a longitudinal randomized trial of cognitive training. The Alzheimer’s Disease Neuroimaging Initiative (ADNI, n=819) is an observational cohort study. Nonequivalent alternate versions of the Auditory Verbal Learning Test (AVLT) were administered in both studies. Results Using visual displays, raw and mean-equated AVLT scores in both studies showed obvious nonlinear trajectories in reference groups that should show minimal change, poor equivalence over time (ps≤0.001), and raw scores demonstrated poor fits in models of within-person change (RMSEAs>0.12). Linear and equipercentile equating produced more similar means in reference groups (ps≥0.09) and performed better in growth models (RMSEAs<0.05). Conclusion Equipercentile equating is the preferred equating method because it accommodates tests more difficult than a reference test at different percentiles of performance and performs well in models of within-person trajectory. The method has broad applications in both clinical and research settings to enhance the ability to use nonequivalent test forms. PMID:22540849

Assessment of Atraumatic Restorative Treatment (ART) on the permanent dentition in a primary care setting in Nigeria.

PubMed

Ibiyemi, Olushola; Bankole, Olubunmi Olusola; Oke, Gbemisola Aderemi

2011-02-01

To assess the acceptability of ART and to evaluate on a longitudinal basis the survival rate of single surface occlusal ART restorations in the permanent dentition. Longitudinal Study of ART restorations. Primary Oral Health Care Setting. Aged 8-19 years in a low socioeconomic community, Southwestern Nigeria. Ninety-three ART restorations were applied on single surface occlusal caries by a dentist who had undergone training on ART. Six monthly follow-up of patients to evaluate restoration retention and marginal defect was conducted by an independent evaluator. Over 90.0% of the subjects had never undergone dental treatment, yet 63.0% perceived dental treatment as painful. After undergoing the treatment as many as 98.0% admitted that ART was not painful. On the question of their willingness to make recall visits, about 95.0% responded in the affirmative and about 96.0% reported that they would encourage others to come for treatment. The cumulative survival rate of single surface occlusal ART restorations after 2 years was 93.5% (SE=2.3%). ART was shown to be acceptable and effective in the management of single surface occlusal caries in the permanent dentition in these Nigerian children and adolescents outside the traditional clinical setting. © 2011 FDI World Dental Federation.

Surveying the Nation: Longitudinal Surveys and the Construction of National Solutions to Educational Inequity

ERIC Educational Resources Information Center

Hutt, Ethan L.

2016-01-01

This paper examines the origins and influences of the introduction of longitudinal student data-sets as a way of gaining insight into the operation of American schools and as a tool for policy-makers. The paper argues that the creation of this new form of data in the 1960s and 1970s represented a relatively new way of thinking about American…

Pooling Data from Multiple Longitudinal Studies: The Role of Item Response Theory in Integrative Data Analysis

PubMed Central

Curran, Patrick J.; Hussong, Andrea M.; Cai, Li; Huang, Wenjing; Chassin, Laurie; Sher, Kenneth J.; Zucker, Robert A.

2010-01-01

There are a number of significant challenges encountered when studying development over an extended period of time including subject attrition, changing measurement structures across group and developmental period, and the need to invest substantial time and money. Integrative data analysis is an emerging set of methodologies that overcomes many of the challenges of single sample designs through the pooling of data drawn from multiple existing developmental studies. This approach is characterized by a host of advantages, but this also introduces several new complexities that must be addressed prior to broad adoption by developmental researchers. In this paper we focus on methods for fitting measurement models and creating scale scores using data drawn from multiple longitudinal studies. We present findings from the analysis of repeated measures of internalizing symptomatology that were pooled from three existing developmental studies. We describe and demonstrate each step in the analysis and we conclude with a discussion of potential limitations and directions for future research. PMID:18331129

Symptom Trajectories Among Child Survivors of Maltreatment: Findings from the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN).

PubMed

Lauterbach, Dean; Armour, Cherie

2016-02-01

Very few studies have investigated the longitudinal trajectory of depression and anxiety related symptomatology among child victims of maltreatment or among those at risk for maltreatment. The current study examined latent class trajectories of anxiety/depression symptoms in a sample of 1354 (n = 657 boys, n = 697 girls) victimized or at risk children using data collected from the Longtitudinal Studies of Child Abuse and Neglect (LONGSCAN). Four trajectory groups were identified labeled low-stable, moderate-stable, moderate-increasing, and high-decreasing. This study also sought to investigate predictors of group membership. Relative to the low-stable group, membership in the three more pathological groups (i.e., moderate-stable, moderate-increasing, and high-decreasing) was predicted by a greater number of maltreatment allegations, more visits to a primary care physician for psychological issues, less perceived support by primary maternal caregiver, and lower rated popularity of the child. Implications for early identification of child maltreatment victims in primary health care settings was discussed.

Academic Crosswinds: When Professional Ethics and Professional Incentives Clash

ERIC Educational Resources Information Center

O'Neil, Jane

2016-01-01

This article provides a useful and perhaps not uncommon anecdote for researchers thinking about sharing professional expectations, scarce resources, "public good" aspects of academic inquiry, and professional responsibility. It appears as follows: Two sets of researchers, using a respected national longitudinal data set, have been…

The evaluation of complex interventions in palliative care: an exploration of the potential of case study research strategies.

PubMed

Walshe, Catherine

2011-12-01

Complex, incrementally changing, context dependent and variable palliative care services are difficult to evaluate. Case study research strategies may have potential to contribute to evaluating such complex interventions, and to develop this field of evaluation research. This paper explores definitions of case study (as a unit of study, a process, and a product) and examines the features of case study research strategies which are thought to confer benefits for the evaluation of complex interventions in palliative care settings. Ten features of case study that are thought to be beneficial in evaluating complex interventions in palliative care are discussed, drawing from exemplars of research in this field. Important features are related to a longitudinal approach, triangulation, purposive instance selection, comprehensive approach, multiple data sources, flexibility, concurrent data collection and analysis, search for proving-disproving evidence, pattern matching techniques and an engaging narrative. The limitations of case study approaches are discussed including the potential for subjectivity and their complex, time consuming and potentially expensive nature. Case study research strategies have great potential in evaluating complex interventions in palliative care settings. Three key features need to be exploited to develop this field: case selection, longitudinal designs, and the use of rival hypotheses. In particular, case study should be used in situations where there is interplay and interdependency between the intervention and its context, such that it is difficult to define or find relevant comparisons.

A review of longitudinal community and hospital placements in medical education: BEME Guide No. 26.

PubMed

Thistlethwaite, J E; Bartle, Emma; Chong, Amy Ai Ling; Dick, Marie-Louise; King, David; Mahoney, Sarah; Papinczak, Tracey; Tucker, George

2013-08-01

Traditionally, clinical learning for medical students consists of short-term and opportunistic encounters with primarily acute-care patients, supervised by an array of clinician preceptors. In response to educational concerns, some medical schools have developed longitudinal placements rather than short-term rotations. Many of these longitudinal placements are also integrated across the core clinical disciplines, are commonly termed longitudinal integrated clerkships (LICs) and often situated in rural locations. This review aimed to explore, analyse and synthesise evidence relating to the effectiveness of longitudinal placements, for medical students in particular to determine which aspects are most critical to successful outcomes. Extensive search of the literature resulted in 1679 papers and abstracts being considered, with 53 papers ultimately being included for review. The review group coded these 53 papers according to standard BEME review guidelines. Specific information extracted included: data relating to effectiveness, the location of the study, number of students involved, format, length and description of placement, the learning outcomes, research design, the impact level for evaluation and the main evaluation methods and findings. We applied a realist approach to consider what works well for whom and under what circumstances. The early LICs were all community-based immersion programs, situated in general practice and predominantly in rural settings. More recent LIC innovations were situated in tertiary-level specialist ambulatory care in urban settings. Not all placements were integrated across medical disciplines but were longitudinal in relation to location, patient base and/or supervision. Twenty-four papers focussed on one of four programs from different viewpoints. Most evaluations were student opinion (survey, interview, focus group) and/or student assessment results. Placements varied from one half day per week for six months through to full time immersion for more than 12 months. The predominant mechanism relating to factors influencing effectiveness was continuity of one or more of: patient care, supervision and mentorship, peer group and location. The success of LICs and participation satisfaction depended on the preparation of both students and clinical supervisors, and the level of support each received from their academic institutions. Longitudinal placements, including longitudinal integrated placements, are gaining in popularity as an alternative to traditional block rotations. Although relatively few established LICs currently exist, medical schools may look for ways to incorporate some of the principles of LICs more generally in their clinical education programmes. Further research is required to ascertain the optimum length of time for placements depending on the defined learning outcomes and timing within the programme, which students are most likely to benefit and the effects of context such as location and type of integration.

Noise-induced hearing loss in a longitudinal study of Norwegian railway workers

PubMed Central

Lie, Arve; Skogstad, Marit; Johnsen, Torstein Seip; Engdahl, Bo; Tambs, Kristian

2016-01-01

Objective The aim of this study was to analyse longitudinal data to assess the risk of noise-induced hearing loss (NIHL) in Norwegian railway workers. Design Longitudinal. Setting A major Norwegian railway company. Methods We examined data from the first and last audiograms for the period 1991–2014, from 9640 railway workers with varying occupational noise exposure and with an average observation period of 10 years. The course of hearing acuity in seven groups of railway workers (train drivers, conductors, bus drivers, traffic controllers, train maintenance workers, track maintenance workers and others) were compared with each other and with ISO standards (ISO 1999). Results The change in hearing threshold during the observation period was 2–3 dB in the 0.5–4 kHz range and 6–7 dB in the 3–6 kHz range adjusted for age and sex, for all occupational groups, which is slightly less than expected (8 dB) according to ISO 1999. Conclusions The risk of NIHL in Norwegian railway workers during the period 1991–2014 has been negligible. PMID:27591022

Longitudinal changes in ventral and dorsal neck muscle layers during loading against gravity in healthy volunteers using speckle tracking.

PubMed

Peolsson, Anneli; Peolsson, Michael

2014-05-01

This study aimed to describe and compare the longitudinal mechanical activity, deformation, and deformation rate of the different layers of dorsal and ventral neck muscles in healthy volunteers during head lifts against gravity. The cross-sectional study included 19 healthy volunteers (mean age, 28 years; SD, 7 years). Ultrasound with speckle-tracking analysis was used to investigate longitudinal mechanical activation, deformation, and deformation rate of dorsal and ventral neck muscles in real time during a head lift. Significance levels were set as P = .025 or P = .0125, depending on the number of comparisons. The dorsal neck muscles did not significantly differ in deformation (P > .04); however, the multifidus had a higher deformation rate than all other dorsal muscles (P < .003). The sternocleidomastoid had significantly higher deformation than the longus capitis (P = .005) and colli (P = .001) but a lower deformation rate than the longus colli (P = .02). The sternocleidomastoid deformed more than the deeper muscles, but it did significantly slower than the longus colli. Among the dorsal muscles, the deepest (the multifidus) had the highest deformation rate. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

The Longitudinal Process of Early Parent Involvement on Student Achievement: A Path Analysis

PubMed Central

Hayakawa, Momoko; Englund, Michelle M.; Warner-Richter, Mallory N.; Reynolds, Arthur J

2016-01-01

This longitudinal study investigated the process whereby early parent involvement in preschool effects student achievement from kindergarten through 6th grade. Participants were 1,539 low-income, mainly African American children and their mothers, in the Chicago Longitudinal Study. Program children (N = 989) received one or two years of the Child-Parent Center (CPC) program – a preschool intervention that strongly promoted parents' development of parent involvement skills within the school and at home. Children from similar backgrounds who did not attend the CPC, but participated in available local resources (e.g. day care), were obtained as a comparison group (N = 550). Path analysis revealed an interactive process between parent involvement, academic achievement, and children's motivation. Early parent involvement directly influenced kindergarten achievement, which in turn influenced first grade student motivation. Highly motivated children then encouraged parents to continue involvement. The cyclic nature of this process across elementary school was observed. The model accounted for 61% of the variance in 6th grade achievement. Findings suggest that early parent involvement promoted in the CPC program, sets the stage for subsequent parent involvement, student motivation, and academic achievement throughout early and middle childhood. PMID:27867317

A Longitudinal Investigation of Visual Event-Related Potentials in the First Year of Life

ERIC Educational Resources Information Center

Webb, Sara J.; Long, Jeffrey D.; Nelson, Charles A.

2005-01-01

The goal of the current study was to assess general maturational changes in the ERP in the same sample of infants from 4 to 12 months of age. All participants were tested in two experimental manipulations at each age: a test of facial recognition and one of object recognition. Two sets of analyses were undertaken. First, growth curve modeling with…

High School Students' Engagement in Planning Investigations: Findings from a Longitudinal Study in Spain

ERIC Educational Resources Information Center

Crujeiras-Pérez, B.; Jiménez-Aleixandre, M. P.

2017-01-01

This paper examines the process of high school students' planning investigations in the chemistry laboratory across two consecutive academic years in terms of their actions and their progress. The context is a set of five inquiry-based laboratory tasks in which participants (9th and 10th graders, 14-15 and 15-16 years of age) are required to plan…

Closing the Gap: How Sectoral Workforce Development Programs Benefit the Working Poor. SEDLP Research Report. The Sectoral Employment Development Learning Project.

ERIC Educational Resources Information Center

Zandniapour, Lily; Conway, Maureen

The benefits of sectoral workforce development programs to the working poor were examined in a 3-year longitudinal study of participants in six sectoral employment training programs across the United States. The programs, which were all designed to serve low-income clients, provided training in a diverse set of industries, including the following:…

Understanding the Antecedents of Adverse Peer Relationships among Early Adolescents in the United States: An Ecological Systems Analysis

ERIC Educational Resources Information Center

Hong, Jun Sung; Espelage, Dorothy L.; Sterzing, Paul R.

2017-01-01

This study examines ecological level correlates of adverse peer relationships among early adolescents (ages 12-14). Data analysis was conducted using the National Longitudinal Survey of Youth (NLSY). The sample was drawn from the mother-child data set, which included youth who in 2002 or 2004 were living with their mothers and enrolled in school.…

Discipline and Participation: The Long-Term Effects of Suspension and School Security on the Political and Civic Engagement of Youth

ERIC Educational Resources Information Center

Kupchik, Aaron; Catlaw, Thomas J.

2015-01-01

This study uses the National Longitudinal Survey of Adolescent Health data set to evaluate the long-term influence of school discipline and security on political and civic participation. We find that young adults with a history of school suspension are less likely than others to vote and volunteer in civic activities years later, suggesting that…

Learning Styles in the e-Learning Environment: The Approaches and Research on Longitudinal Changes

ERIC Educational Resources Information Center

Doulik, Pavel; Skoda, Jiri; Simonova, Ivana

2017-01-01

The paper focuses on the field of learning styles in e-learning. The study is structured in two main parts: (1) a brief overview of traditional approaches to learning styles is presented and their role in the process of instruction is set; this part results in the reflection of current state, when learning styles are considered within e-learning;…

Occupational and Educational Biographies of Older Workers and Their Participation in Further Education in Germany

ERIC Educational Resources Information Center

Schmidt-Hertha, Bernhard; Müller, Margaretha

2017-01-01

The adult cohort of the German National Educational Panel Study (NEPS) provides data from six sets of longitudinal data derived from 11,932 German adults. We used the NEPS data to look at the effects of formal education in adulthood and occupational changes on participation in further vocational education and training in order to gain a better…

Longitudinal Predictors of Disciplinary Alternative School Placement and the Risk of Subsequent Juvenile Detention in a Cohort of Third Grade Children

ERIC Educational Resources Information Center

Vanderhaar, Judi Elisa

2010-01-01

Alternative school settings for students who are identified as "disruptive or dangerous" are playing an increasingly prominent role in the world of public education, yet many gaps in the research literature are abound. This dissertation study is an effort to contribute to an understanding of the students placed in these alternative schools,…

Estimation of strength parameters of small-bore metal-polymer pipes

NASA Astrophysics Data System (ADS)

Shaydakov, V. V.; Chernova, K. V.; Penzin, A. V.

2018-03-01

The paper presents results from a set of laboratory studies of strength parameters of small-bore metal-polymer pipes of type TG-5/15. A wave method was used to estimate the provisional modulus of elasticity of the metal-polymer material of the pipes. Longitudinal deformation, transverse deformation and leak-off pressure were determined experimentally, with considerations for mechanical damage and pipe bend.

A Comparison of Classroom and Online Asynchronous Problem-Based Learning for Students Undertaking Statistics Training as Part of a Public Health Masters Degree

ERIC Educational Resources Information Center

de Jong, N.; Verstegen, D. M. L.; Tan, F. E. S.; O'Connor, S. J.

2013-01-01

This case-study compared traditional, face-to-face classroom-based teaching with asynchronous online learning and teaching methods in two sets of students undertaking a problem-based learning module in the multilevel and exploratory factor analysis of longitudinal data as part of a Masters degree in Public Health at Maastricht University. Students…

Developmental Trajectories of Work Values and Job Entitlement Beliefs in the Transition to Adulthood

ERIC Educational Resources Information Center

Chow, Angela; Krahn, Harvey J.; Galambos, Nancy L.

2014-01-01

Employing a life span developmental systems perspective, this study used a 5-wave (1985-1992) Canadian longitudinal data set (N = 404) to examine trajectories of intrinsic and extrinsic work values and job entitlement beliefs from age 18 to 25. Piecewise growth models (Slope 1: age 18-20; Slope 2: age 20-25) showed intriguing patterns of change.…

School Completion: What We Learn from Different Measures of Family Background. Longitudinal Surveys of Australian Youth. Research Report 59

ERIC Educational Resources Information Center

Homel, Jacqueline; Mavisakalyan, Astghik; Nguyen, Ha Trong; Ryan, Chris

2012-01-01

This paper examines how disadvantage affects educational outcomes, in this instance, Year 12 completion. While previous studies have found a strong link between parental education or occupational status and Year 12 completion, this research was able to capture a broader set of cultural, material and resource aspects of disadvantage. It did this by…

Studying learning in the healthcare setting: the potential of quantitative diary methods.

PubMed

Ciere, Yvette; Jaarsma, Debbie; Visser, Annemieke; Sanderman, Robbert; Snippe, Evelien; Fleer, Joke

2015-08-01

Quantitative diary methods are longitudinal approaches that involve the repeated measurement of aspects of peoples' experience of daily life. In this article, we outline the main characteristics and applications of quantitative diary methods and discuss how their use may further research in the field of medical education. Quantitative diary methods offer several methodological advantages, such as measuring aspects of learning with great detail, accuracy and authenticity. Moreover, they enable researchers to study how and under which conditions learning in the health care setting occurs and in which way learning can be promoted. Hence, quantitative diary methods may contribute to theory development and the optimization of teaching methods in medical education.

Can We Study Autonomous Driving Comfort in Moving-Base Driving Simulators? A Validation Study.

PubMed

Bellem, Hanna; Klüver, Malte; Schrauf, Michael; Schöner, Hans-Peter; Hecht, Heiko; Krems, Josef F

2017-05-01

To lay the basis of studying autonomous driving comfort using driving simulators, we assessed the behavioral validity of two moving-base simulator configurations by contrasting them with a test-track setting. With increasing level of automation, driving comfort becomes increasingly important. Simulators provide a safe environment to study perceived comfort in autonomous driving. To date, however, no studies were conducted in relation to comfort in autonomous driving to determine the extent to which results from simulator studies can be transferred to on-road driving conditions. Participants ( N = 72) experienced six differently parameterized lane-change and deceleration maneuvers and subsequently rated the comfort of each scenario. One group of participants experienced the maneuvers on a test-track setting, whereas two other groups experienced them in one of two moving-base simulator configurations. We could demonstrate relative and absolute validity for one of the two simulator configurations. Subsequent analyses revealed that the validity of the simulator highly depends on the parameterization of the motion system. Moving-base simulation can be a useful research tool to study driving comfort in autonomous vehicles. However, our results point at a preference for subunity scaling factors for both lateral and longitudinal motion cues, which might be explained by an underestimation of speed in virtual environments. In line with previous studies, we recommend lateral- and longitudinal-motion scaling factors of approximately 50% to 60% in order to obtain valid results for both active and passive driving tasks.

Modeling Longitudinal Dynamics in the Fermilab Booster Synchrotron

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

Ostiguy, Jean-Francois; Bhat, Chandra; Lebedev, Valeri

2016-06-01

The PIP-II project will replace the existing 400 MeV linac with a new, CW-capable, 800 MeV superconducting one. With respect to current operations, a 50% increase in beam intensity in the rapid cycling Booster synchrotron is expected. Booster batches are combined in the Recycler ring; this process limits the allowed longitudinal emittance of the extracted Booster beam. To suppress eddy currents, the Booster has no beam pipe; magnets are evacuated, exposing the beam to core laminations and this has a substantial impact on the longitudinal impedance. Noticeable longitudinal emittance growth is already observed at transition crossing. Operation at higher intensitymore » will likely necessitate mitigation measures. We describe systematic efforts to construct a predictive model for current operating conditions. A longitudinal only code including a laminated wall impedance model, space charge effects, and feedback loops is developed. Parameter validation is performed using detailed measurements of relevant beam, rf and control parameters. An attempt is made to benchmark the code at operationally favorable machine settings.« less

Learning from Friends: Measuring Influence in a Dyadic Computer Instructional Setting

ERIC Educational Resources Information Center

DeLay, Dawn; Hartl, Amy C.; Laursen, Brett; Denner, Jill; Werner, Linda; Campe, Shannon; Ortiz, Eloy

2014-01-01

Data collected from partners in a dyadic instructional setting are, by definition, not statistically independent. As a consequence, conventional parametric statistical analyses of change and influence carry considerable risk of bias. In this article, we illustrate a strategy to overcome this obstacle: the longitudinal actor-partner interdependence…

Feasibility of Spanish-language acquisition for acute medical care providers: novel curriculum for emergency medicine residencies.

PubMed

Grall, Kristi H; Panchal, Ashish R; Chuffe, Eliud; Stoneking, Lisa R

2016-01-01

Language and cultural barriers are detriments to quality health care. In acute medical settings, these barriers are more pronounced, which can lead to poor patient outcomes. We implemented a longitudinal Spanish-language immersion curriculum for emergency medicine (EM) resident physicians. This curriculum includes language and cultural instruction, and is integrated into the weekly EM didactic conference, longitudinal over the entire 3-year residency program. Language proficiency was assessed at baseline and annually on the Interagency Language Roundtable (ILR) scale, via an oral exam conducted by the same trained examiner each time. The objective of the curriculum was improvement of resident language skills to ILR level 1+ by year 3. Significance was evaluated through repeated-measures analysis of variance. The curriculum was launched in July 2010 and followed through June 2012 (n=16). After 1 year, 38% had improved over one ILR level, with 50% achieving ILR 1+ or above. After year 2, 100% had improved over one level, with 90% achieving the objective level of ILR 1+. Mean ILR improved significantly from baseline, year 1, and year 2 (F=55, df =1; P<0.001). Implementation of a longitudinal, integrated Spanish-immersion curriculum is feasible and improves language skills in EM residents. The curriculum improved EM-resident language proficiency above the goal in just 2 years. Further studies will focus on the effect of language acquisition on patient care in acute settings.

Mediating Mechanisms for the Intergenerational Transmission of Constructive Parenting: A Prospective Longitudinal Study

PubMed Central

Chen, Zeng-yin; Liu, Ruth X.; Kaplan, Howard B.

2010-01-01

Based on a prospective longitudinal panel data set that was collected at three developmental stages—early adolescence, young adulthood, and middle adulthood— this study investigates marital satisfaction and educational attainment as mediating mechanisms as well as gender's moderating effect for the intergenerational transmission of constructive parenting (N = 1,560). The results show that perceived satisfying experiences with parents during early adolescence are positively related to marital satisfaction and educational attainment in young adulthood, which, in turn, are positively related to individuals' utilization of constructive parenting in middle adulthood. The two mediating mechanisms account for most of the direct effect of the intergenerational transmission of constructive parenting. Furthermore, the mediating effect of marital relationship is stronger for current fathers than for mothers because of a stronger association between marital satisfaction and constructive parenting for men. The implications are discussed. PMID:20357901

Improved Doubly Robust Estimation when Data are Monotonely Coarsened, with Application to Longitudinal Studies with Dropout

PubMed Central

Tsiatis, Anastasios A.; Davidian, Marie; Cao, Weihua

2010-01-01

Summary A routine challenge is that of making inference on parameters in a statistical model of interest from longitudinal data subject to drop out, which are a special case of the more general setting of monotonely coarsened data. Considerable recent attention has focused on doubly robust estimators, which in this context involve positing models for both the missingness (more generally, coarsening) mechanism and aspects of the distribution of the full data, that have the appealing property of yielding consistent inferences if only one of these models is correctly specified. Doubly robust estimators have been criticized for potentially disastrous performance when both of these models are even only mildly misspecified. We propose a doubly robust estimator applicable in general monotone coarsening problems that achieves comparable or improved performance relative to existing doubly robust methods, which we demonstrate via simulation studies and by application to data from an AIDS clinical trial. PMID:20731640

Flight Controllability Limits and Related Human Transfer Functions as Determined from Simulator and Flight Tests

NASA Technical Reports Server (NTRS)

Taylor, Lawrence W., Jr.; Day, Richard E.

1961-01-01

A simulator study and flight tests were performed to determine the levels of static stability and damping necessary to enable a pilot to control the longitudinal and lateral-directional dynamics of a vehicle for short periods of time. Although a basic set of aerodynamic characteristics was used, the study was conducted so that the results would be applicable to a wide range of flight conditions and configurations. Novel piloting techniques were found which enabled the pilot to control the vehicle at conditions that were otherwise uncontrollable. The influence of several critical factors in altering the controllability limits was also investigated. Several human transfer functions were used which gave fairly good representations of the controllability limits determined experimentally for the short-period longitudinal, directional, and lateral modes. A transfer function with approximately the same gain and phase angle as the pilot at the controlling frequencies along the controllability limits was also derived.

Longitudinal analysis of categorical epidemiological data: a study of Three Mile Island.

PubMed

Fienberg, S E; Bromet, E J; Follmann, D; Lambert, D; May, S M

1985-11-01

The accident at the Three Mile Island nuclear power plant in 1979 led to an unprecedented set of events with potentially life threatening implications. This paper focusses on the analysis of a longitudinal study of the psychological well-being of the mothers of young children living within 10 miles of the plant. The initial analyses of the data utilize loglinear/logit model techniques from the contingency table literature, and involve the fitting of a sequence of logit models. The inadequancies of these analyses are noted, and a new class of mixture models for logistic response structures is introduced to overcome the noted shortcomings. The paper includes a brief outline of the methodology relevant for the fitting of these models using the method of maximum likelihood, and then the model is applied to the TMI data. The paper concludes with a discussion of some of the substantive implications of the mixture model analysis.

Simple Perfusion Apparatus (SPA) for Manipulation, Tracking and Study of Oocytes and Embryos

PubMed Central

Angione, Stephanie L.; Oulhen, Nathalie; Brayboy, Lynae M.; Tripathi, Anubhav; Wessel, Gary M.

2016-01-01

Objective To develop and implement a device and protocol for oocyte analysis at a single cell level. The device must be capable of high resolution imaging, temperature control, perfusion of media, drugs, sperm, and immunolabeling reagents all at defined flow-rates. Each oocyte and resultant embryo must remain spatially separated and defined. Design Experimental laboratory study Setting University and Academic Center for reproductive medicine. Patients/Animals Women with eggs retrieved for ICSI cycles, adult female FVBN and B6C3F1 mouse strains, sea stars. Intervention Real-time, longitudinal imaging of oocytes following fluorescent labeling, insemination, and viability tests. Main outcome measure(s) Cell and embryo viability, immunolabeling efficiency, live cell endocytosis quantitation, precise metrics of fertilization and embryonic development. Results Single oocytes were longitudinally imaged following significant changes in media, markers, endocytosis quantitation, and development, all with supreme control by microfluidics. Cells remained viable, enclosed, and separate for precision measurements, repeatability, and imaging. Conclusions We engineered a simple device to load, visualize, experiment, and effectively record individual oocytes and embryos, without loss of cells. Prolonged incubation capabilities provide longitudinal studies without need for transfer and potential loss of cells. This simple perfusion apparatus (SPA) provides for careful, precise, and flexible handling of precious samples facilitating clinical in vitro fertilization approaches. PMID:25450296

Browsing, Posting, and Liking on Instagram: The Reciprocal Relationships Between Different Types of Instagram Use and Adolescents' Depressed Mood.

PubMed

Frison, Eline; Eggermont, Steven

2017-10-01

Although studies have shown that Instagram use and young adults' mental health are cross-sectionally associated, longitudinal evidence is lacking. In addition, no study thus far examined this association, or the reverse, among adolescents. To address these gaps, we set up a longitudinal panel study among 12- to 19-year-old Flemish adolescents to investigate the reciprocal relationships between different types of Instagram use and depressed mood. Self-report data from 671 adolescent Instagram users (61% girls; M Age  = 14.96; SD = 1.29) were used to examine our research question and test our hypotheses. Structural equation modeling showed that Instagram browsing at Time 1 was related to increases in adolescents' depressed mood at Time 2. In addition, adolescents' depressed mood at Time 1 was related to increases in Instagram posting at Time 2. These relationships were similar among boys and girls. Potential explanations for the study findings and suggestions for future research are discussed.

A longitudinal investigation of the relationship between maternal mind-mindedness and theory of mind.

PubMed

Kirk, Elizabeth; Pine, Karen; Wheatley, Lisa; Howlett, Neil; Schulz, Joerg; Fletcher, Ben C

2015-11-01

Data are presented from a longitudinal investigation examining the relationship between maternal mind-mindedness (MM) in infancy and socio-cognitive development in childhood. We revisited children (n = 18) who had taken part in a longitudinal study as infants. MM had been assessed at 10, 12, 16, and 20 months of age. We followed up these children at 5-6 years of age to test their higher order theory of mind (ToM) (using the strange stories task). The convergent validity, temporal stability, and predictive validity of the construct of MM were examined in a longitudinal data set. The five measures of MM were not significantly correlated. Mother's production of appropriate mind-related comments (but no other measures) showed evidence of temporal stability throughout infancy. Thus, MM (as measured by appropriate mind-related comments) was confirmed as a stable construct. Children's ToM at 5-6 years of age was significantly predicted by their mother's MM up to 4 years earlier, with MM accounting for 40% of the variance of the strange stories task scores. These findings identify a relationship between MM across a protracted period of infancy and socio-cognitive development at 5-6 years of age. © 2015 The British Psychological Society.

The impact of preload reduction with head-up tilt testing on longitudinal and transverse left ventricular mechanics: a study utilizing deformation volume analysis

PubMed Central

Schneider, Caroline; Forsythe, Lynsey; Somauroo, John; George, Keith

2018-01-01

Background Left ventricular (LV) function is dependent on load, intrinsic contractility and relaxation with a variable impact on specific mechanics. Strain (ε) imaging allows the assessment of cardiac function; however, the direct relationship between volume and strain is currently unknown. The aim of this study was to establish the impact of preload reduction through head-up tilt (HUT) testing on simultaneous left ventricular (LV) longitudinal and transverse function and their respective contribution to volume change. Methods A focused transthoracic echocardiogram was performed on 10 healthy male participants (23 ± 3 years) in the supine position and following 1 min and 5 min of HUT testing. Raw temporal longitudinal ε (Ls) and transverse ε (Ts) values were exported and divided into 5% increments across the cardiac cycle and corresponding LV volumes were traced at each 5% increment. This provided simultaneous LV longitudinal and transverse ε and volume loops (deformation volume analysis – DVA). Results There was a leftward shift of the ε-volume loop from supine to 1 min and 5 min of HUT (P < 0.001). Moreover, longitudinal shortening was reduced (P < 0.001) with a concomitant increase in transverse thickening from supine to 1 min, which was further augmented at 5 min (P = 0.018). Conclusions Preload reduction occurs within 1 min of HUT but does not further reduce at 5 min. This decline is associated with a decrease in longitudinal ε and concomitant increase in transverse ε. Consequently, augmented transverse relaxation appears to be an important factor in the maintenance of LV filling in the setting of reduced preload. DVA provides information on the relative contribution of mechanics to a change in LV volume and may have a role in the assessment of clinical populations. PMID:29339401

The impact of preload reduction with head-up tilt testing on longitudinal and transverse left ventricular mechanics: a study utilizing deformation volume analysis.

PubMed

Schneider, Caroline; Forsythe, Lynsey; Somauroo, John; George, Keith; Oxborough, David

2018-03-01

Left ventricular (LV) function is dependent on load, intrinsic contractility and relaxation with a variable impact on specific mechanics. Strain (ε) imaging allows the assessment of cardiac function; however, the direct relationship between volume and strain is currently unknown. The aim of this study was to establish the impact of preload reduction through head-up tilt (HUT) testing on simultaneous left ventricular (LV) longitudinal and transverse function and their respective contribution to volume change. A focused transthoracic echocardiogram was performed on 10 healthy male participants (23 ± 3 years) in the supine position and following 1 min and 5 min of HUT testing. Raw temporal longitudinal ε (Ls) and transverse ε (Ts) values were exported and divided into 5% increments across the cardiac cycle and corresponding LV volumes were traced at each 5% increment. This provided simultaneous LV longitudinal and transverse ε and volume loops (deformation volume analysis - DVA). There was a leftward shift of the ε-volume loop from supine to 1 min and 5 min of HUT ( P  < 0.001). Moreover, longitudinal shortening was reduced ( P  < 0.001) with a concomitant increase in transverse thickening from supine to 1 min, which was further augmented at 5 min ( P  = 0.018). Preload reduction occurs within 1 min of HUT but does not further reduce at 5 min. This decline is associated with a decrease in longitudinal ε and concomitant increase in transverse ε. Consequently, augmented transverse relaxation appears to be an important factor in the maintenance of LV filling in the setting of reduced preload. DVA provides information on the relative contribution of mechanics to a change in LV volume and may have a role in the assessment of clinical populations. © 2018 The authors.

To track or not to track: user reactions to concepts in longitudinal health monitoring.

PubMed

Beaudin, Jennifer S; Intille, Stephen S; Morris, Margaret E

2006-01-01

Advances in ubiquitous computing, smart homes, and sensor technologies enable novel, longitudinal health monitoring applications in the home. Many home monitoring technologies have been proposed to detect health crises, support aging-in-place, and improve medical care. Health professionals and potential end users in the lay public, however, sometimes question whether home health monitoring is justified given the cost and potential invasion of privacy. The aim of the study was to elicit specific feedback from health professionals and laypeople about how they might use longitudinal health monitoring data for proactive health and well-being. Interviews were conducted with 8 health professionals and 26 laypeople. Participants were asked to evaluate mock data visualization displays that could be generated by novel home monitoring systems. The mock displays were used to elicit reactions to longitudinal monitoring in the home setting as well as what behaviors, events, and physiological indicators people were interested in tracking. Based on the qualitative data provided by the interviews, lists of benefits of and concerns about health tracking from the perspectives of the practitioners and laypeople were compiled. Variables of particular interest to the interviewees, as well as their specific ideas for applications of collected data, were documented. Based upon these interviews, we recommend that ubiquitous "monitoring" systems may be more readily adopted if they are developed as tools for personalized, longitudinal self-investigation that help end users learn about the conditions and variables that impact their social, cognitive, and physical health.

Temperature in the anterior chamber during phacoemulsification.

PubMed

Suzuki, Hisaharu; Oki, Kotaro; Igarashi, Tsutomu; Shiwa, Toshihiko; Takahashi, Hiroshi

2014-05-01

To evaluate changes in the aqueous humor temperature using 2 phacoemulsification units (Stellaris 28.5 kHz device and Whitestar Signature 40 kHz device). Nippon Medical School, Musashikosugi Hospital, Kawasaki City, Kanagawa, Japan. Experimental study. Aqueous humor temperatures were measured with a temperature probe set in the anterior chamber during ultrasound (US) oscillation in porcine eyes under 5 conditions. Continuous longitudinal oscillation caused a rapid rise in aqueous humor temperature, while the pulse and elliptical modes suppressed temperature elevation. Reducing the number of US tip vibrations did not reduce the temperature in the anterior chamber. However, raising the vacuum setting allowed the aspirations to rise to the set value, thereby lowering the temperature in the anterior chamber. Because differences in the phacoemulsification settings can lead to temperature elevations in the anterior chamber, surgeons must carefully monitor these settings to prevent corneal tissue damage. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Serum carotenoid and tocopherol concentrations and risk of asthma in childhood: a nested case-control study.

PubMed

Hämäläinen, N; Nwaru, B I; Erlund, I; Takkinen, H-M; Ahonen, S; Toppari, J; Ilonen, J; Veijola, R; Knip, M; Kaila, M; Virtanen, S M

2017-03-01

The antioxidant hypothesis regarding the risk of asthma in childhood has resulted in inconsistent findings. Some data indicate that the role of antioxidants in childhood asthma risk may have a critical time window of effect, but only a well-designed longitudinal cohort study can clarify this hypothesis. To study the longitudinal associations between serum carotenoid and tocopherol concentrations during the first 4 years of life and asthma risk by the age of 5 years. Based on a case-control design nested within a Finnish birth cohort, 146 asthma cases were matched to 270 controls on birth time, sex, genetic risk, and birth place. Non-fasting blood samples were collected at the ages of 1, 1.5, 2, 3, and 4 years and serum carotenoids and tocopherols were analysed. Parents reported the presence and age at start of persistent doctor-diagnosed asthma in the child at the age of 5 years. Data analyses were conducted using generalized estimating equations. We did not find strong associations between serum carotenoids and tocopherols and the risk of asthma based on age-specific and longitudinal analyses. Both lower and higher quarters of α-carotene and γ-tocopherol increased the risk of asthma. The current findings do not support the suggestion that the increased prevalence of asthma may be a consequence of decreased intake of antioxidant nutrients. Moreover, we did not confirm any critical time window of impact of antioxidants on asthma risk. Replication of these findings in similar longitudinal settings will strengthen this evidence base. © 2017 John Wiley & Sons Ltd.

Longitudinal associations of neighborhood collective efficacy and maternal corporal punishment with behavior problems in early childhood.

PubMed

Ma, Julie; Grogan-Kaylor, Andrew

2017-06-01

Neighborhood and parenting influences on early behavioral outcomes are strongly dependent upon a child's stage of development. However, little research has jointly considered the longitudinal associations of neighborhood and parenting processes with behavior problems in early childhood. To address this limitation, this study explores the associations of neighborhood collective efficacy and maternal corporal punishment with the longitudinal patterns of early externalizing and internalizing behavior problems. The study sample consisted of 3,705 families from a nationally representative cohort study of urban families. Longitudinal multilevel models examined the associations of collective efficacy and corporal punishment with behavior problems at age 3, as well as with patterns of behavior problems between the ages 3 to 5. Interactions between the main predictors and child age tested whether neighborhood and parent relationships with child behavior varied over time. Mediation analysis examined whether neighborhood influences on child behavior were mediated by parenting. The models controlled for a comprehensive set of possible confounders at the child, parent, and neighborhood levels. Results indicate that both maternal corporal punishment and low neighborhood collective efficacy were significantly associated with increased behavior problems. The significant interaction between collective efficacy and child age with internalizing problems suggests that neighborhood influences on internalizing behavior were stronger for younger children. The indirect effect of low collective efficacy on behavior problems through corporal punishment was not significant. These findings highlight the importance of multilevel interventions that promote both neighborhood collective efficacy and nonphysical discipline in early childhood. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Cohort profile: Wisconsin longitudinal study (WLS).

PubMed

Herd, Pamela; Carr, Deborah; Roan, Carol

2014-02-01

The Wisconsin Longitudinal Study (WLS) is a longitudinal study of men and women who graduated from Wisconsin high schools in 1957 and one of their randomly selected siblings. Wisconsin is located in the upper midwest of the United States and had a population of approximately 14 000 000 in 1957, making it the 14th most populous state at that time. Data spanning almost 60 years allow researchers to link family background, adolescent characteristics, educational experiences, employment experiences, income, wealth, family formation and social and religious engagement to midlife and late-life physical health, mental health, psychological well-being, cognition, end of life planning and mortality. The WLS is one of the few longitudinal data sets that include an administrative measure of cognition from childhood. Further, recently collected saliva samples allow researchers to explore the inter-relationships among genes, behaviours and environment, including genetic determinants of behaviours (e.g. educational attainment); the interactions between genes and environment; and how these interactions predict behaviours. Most panel members were born in 1939, and the sample is broadly representative of White, non-Hispanic American men and women who have completed at least a high school education. Siblings cover several adjoining cohorts: they were born primarily between 1930 and 1948. At each interview, about two-thirds of the sample lived in Wisconsin, and about one-third lived elsewhere in the United States or abroad. The data, along with documentation, are publicly accessible and can be accessed at http://www.ssc.wisc.edu/wlsresearch/. Requests for protected data or assistance should be sent to wls@ssc.wisc.edu.

Crohn's disease in Japan: diagnostic criteria and epidemiology.

PubMed

Yao, T; Matsui, T; Hiwatashi, N

2000-10-01

New diagnostic criteria for Crohn's disease and a review of Japanese epidemiologic studies are presented. New diagnostic criteria for Crohn's disease were established by the Research Committee of Inflammatory Bowel Disease, set up by the Japanese Ministry of Health and Welfare. For a definite diagnosis one of the following three conditions is required: 1) longitudinal ulcer or luminal deformity induced by longitudinal ulcer or cobblestone pattern, 2) intestinal small aphthous ulcerations arranged in a longitudinal fashion for at least three months plus noncaseating granulomas, and 3) multiple small aphthous ulcerations in both the upper and lower digestive tract not necessarily with longitudinal arrangement, for at least three months, plus noncaseating granulomas. Moreover, ulcerative colitis, ischemic enterocolitis, and acute infectious enterocolitis should be excluded. Data from the Japanese Ministry of Health and Welfare, in addition to data collected from two study groups, these being the two largest studies in Japan, are reviewed with regard to epidemiology. The number of patients with Crohn's disease has increased remarkably. The prevalence and the annual incidence of patients with Crohn's disease in Japan were estimated to be approximately 2.9 and 0.6 per 10(5) population in 1986, respectively, and 13.5 and 1.2 per 10(5) population in 1998. Characteristic features of Crohn's disease in Japan are that the male-female ratio exceeds 2, and that there is no second peak of incidence in the age group of 55 to 65 years. Clinically, Crohn's disease with only multiple small aphthous ulcerations, which is the earliest stage of the disease that is diagnosable, was found in 5 percent of patients.

Accelerated Optical Projection Tomography Applied to In Vivo Imaging of Zebrafish

PubMed Central

Correia, Teresa; Yin, Jun; Ramel, Marie-Christine; Andrews, Natalie; Katan, Matilda; Bugeon, Laurence; Dallman, Margaret J.; McGinty, James; Frankel, Paul; French, Paul M. W.; Arridge, Simon

2015-01-01

Optical projection tomography (OPT) provides a non-invasive 3-D imaging modality that can be applied to longitudinal studies of live disease models, including in zebrafish. Current limitations include the requirement of a minimum number of angular projections for reconstruction of reasonable OPT images using filtered back projection (FBP), which is typically several hundred, leading to acquisition times of several minutes. It is highly desirable to decrease the number of required angular projections to decrease both the total acquisition time and the light dose to the sample. This is particularly important to enable longitudinal studies, which involve measurements of the same fish at different time points. In this work, we demonstrate that the use of an iterative algorithm to reconstruct sparsely sampled OPT data sets can provide useful 3-D images with 50 or fewer projections, thereby significantly decreasing the minimum acquisition time and light dose while maintaining image quality. A transgenic zebrafish embryo with fluorescent labelling of the vasculature was imaged to acquire densely sampled (800 projections) and under-sampled data sets of transmitted and fluorescence projection images. The under-sampled OPT data sets were reconstructed using an iterative total variation-based image reconstruction algorithm and compared against FBP reconstructions of the densely sampled data sets. To illustrate the potential for quantitative analysis following rapid OPT data acquisition, a Hessian-based method was applied to automatically segment the reconstructed images to select the vasculature network. Results showed that 3-D images of the zebrafish embryo and its vasculature of sufficient visual quality for quantitative analysis can be reconstructed using the iterative algorithm from only 32 projections—achieving up to 28 times improvement in imaging speed and leading to total acquisition times of a few seconds. PMID:26308086

Specificity of the Association between Marital Discord and Longitudinal Changes in Symptoms of Depression and Generalized Anxiety Disorder in the Irish Longitudinal Study on Ageing.

PubMed

Whisman, Mark A; Robustelli, Briana L; Labrecque, Lindsay T

2018-03-25

This longitudinal study was conducted to evaluate actor and partner effects of marital discord on changes in symptoms of depression and generalized anxiety disorder (GAD) in a large population sample of Irish adults (N = 1,445 couples), adjusting for the potential confounds of quality of other social relationships and other psychopathology symptoms. The Actor-Partner Interdependence Model was used to examine actor and partner effects of marital discord on changes in symptoms of depression and GAD at a 2-year follow-up. Additional models examined these associations adjusting for family and friend discord and symptoms of the other type of psychopathology (depressive or GAD symptoms). Actor effects of marital discord on depressive and anxiety symptoms were greater for men than for women. There were significant, positive actor effects of marital discord on depressive symptoms for husbands and wives, which remained significant when adjusting for family and friend discord and GAD symptoms. There were significant, positive actor effects of marital discord on GAD symptoms for husbands, which remained significant when adjusting for family and friend discord and depressive symptoms. Results demonstrate that longitudinal associations between marital discord and depressive symptoms (for wives and husbands) and GAD symptoms (for husbands) are incremental to other rival explanations (family and friend discord and the other set of symptoms). Findings provide evidence for a potential causal association leading from marital discord to symptoms of depression and GAD. © 2018 Family Process Institute.

The impact of preload reduction with head-up tilt testing on longitudinal and transverse left ventricular mechanics.

PubMed

Schneider, Caroline; Forsythe, Lynsey; Somauroo, John; George, Keith; Oxborough, David

2018-01-03

Left ventricular (LV) function is dependent on load, intrinsic contractility and relaxation with a variable impact on specific mechanics. Strain (ε) imaging allows the assessment of cardiac function however the direct relationship between volume and strain is currently unknown. The aim of this study was to establish the impact of preload reduction through head-up tilt (HUT) testing on simultaneous left ventricular (LV) longitudinal and transverse function and their respective contribution to volume change. A focused transthoracic echocardiogram was performed on 10 healthy male participants (23 ± 3 years,) in the supine position and following 1 min and 5 min of HUT testing. Raw temporal longitudinal ε (Ls) and transverse ε (Ts) values were exported and divided into 5% increments across the cardiac cycle and corresponding LV volumes were traced at each 5% increment. This provided simultaneous LV longitudinal and transverse ε and volume-loops (deformation-volume analysis - DVA). There was a leftward- shift of the ε -volume loop from supine to 1 min and 5 min of HUT, p<0.001). Moreover, longitudinal shortening was reduced (p<0.001) with a concomitant increase in transverse thickening from supine to 1min, which was further augmented at 5min (p=0.018). Preload reduction occurs within 1 minute of HUT but does not further reduce at 5 minutes. This decline is associated with a decrease in longitudinal ε and concomitant increase in transverse ε. Consequently, augmented transverse relaxation appears to be an important factor in the maintenance of LV filling in the setting of reduced preload. DVA provides information on the relative contribution of mechanics to a change in LV volume and may have a role in the assessment of clinical populations. © 2018 The authors.

Does psychedelic drug use reduce risk of suicidality? Evidence from a longitudinal community-based cohort of marginalised women in a Canadian setting

PubMed Central

Argento, Elena; Strathdee, Steffanie A; Tupper, Kenneth; Braschel, Melissa; Wood, Evan; Shannon, Kate

2017-01-01

Objective This study aimed to longitudinally investigate whether ever having used a psychedelic drug can have a protective effect on incidence of suicidality among marginalised women. Design Longitudinal community-based cohort study. Setting Data were drawn from a prospective, community-based cohort of marginalised women in Metro Vancouver, Canada. Participants 766 women completed the baseline questionnaire between January 2010 and August 2014. Participants who did not report suicidality at baseline and who completed at least one follow-up visit were included. Main outcome measure Extended Cox regression was used to model predictors of new suicidality (suicide ideation or attempts) over 54-month follow-up. Results Nearly half (46%; n=355) of participants reported prior suicidality and were thus excluded from the present analyses. Of 290 women eligible at baseline, 11% (n=31) reported recent suicidality during follow-up, with an incidence density of 4.42 per 100 person-years (95% CI 3.10 to 6.30). In multivariable analysis, reported lifetime psychedelic drug use was associated with a 60% reduced hazard for suicidality (adjusted HR (AHR) 0.40; 95% CI 0.17 to 0.94). Crystal methamphetamine use (AHR 3.25; 95% CI 1.47 to 7.21) and childhood abuse (AHR 3.54; 95% CI 1.49 to 8.40) remained independent predictors of suicidality. Conclusion The high rate of suicidality identified in this study is of major concern. Alongside emerging evidence on the potential of psychedelic-assisted therapy to treat some mental illness and addiction issues, our findings demonstrate that naturalistic psychedelic drug use is independently associated with reduced suicidality, while other illicit drug use and childhood trauma predispose women to suicidality. While observational, this study supports calls for further investigation of the therapeutic utility of psychedelic drugs in treating poor mental health and promoting mental wellness. PMID:28939573

Analysis of longitudinal data from animals with missing values using SPSS.

PubMed

Duricki, Denise A; Soleman, Sara; Moon, Lawrence D F

2016-06-01

Testing of therapies for disease or injury often involves the analysis of longitudinal data from animals. Modern analytical methods have advantages over conventional methods (particularly when some data are missing), yet they are not used widely by preclinical researchers. Here we provide an easy-to-use protocol for the analysis of longitudinal data from animals, and we present a click-by-click guide for performing suitable analyses using the statistical package IBM SPSS Statistics software (SPSS). We guide readers through the analysis of a real-life data set obtained when testing a therapy for brain injury (stroke) in elderly rats. If a few data points are missing, as in this example data set (for example, because of animal dropout), repeated-measures analysis of covariance may fail to detect a treatment effect. An alternative analysis method, such as the use of linear models (with various covariance structures), and analysis using restricted maximum likelihood estimation (to include all available data) can be used to better detect treatment effects. This protocol takes 2 h to carry out.

Development of a bi-directional standing wave linear piezoelectric actuator with four driving feet.

PubMed

Liu, Yingxiang; Shi, Shengjun; Li, Chunhong; Chen, Weishan; Wang, Liang; Liu, Junkao

2018-03-01

A bi-directional standing wave linear piezoelectric ultrasonic actuator with four driving feet is proposed in this work. Two sandwich type transducers operated in longitudinal-bending hybrid modes are set parallelly. The working mode of the transducer is not simple hybrid vibrations of a longitudinal one and a bending one, but a special coupling vibration mode contained both longitudinal and bending components. Two transducers with the same structure and unsymmetrical boundary conditions are set parallelly to accomplish the bi-directional driving: the first transducer can push the runner forward, while the other one produces the backward driving. In the experiments, two voltages with different amplitudes are applied on the two transducers, respectively: the one with higher voltage serves as the actuator, whereas the other one applied with lower voltage is used to reduce the frictional force. The prototype achieves maximum no-load speed and thrust force of 244 mm/s and 9.8 N. This work gives a new idea for the construction of standing wave piezoelectric ultrasonic actuator with bi-directional driving ability. Copyright © 2017 Elsevier B.V. All rights reserved.

Wind-Tunnel Investigation of the Static Longitudinal Stability Characteristics of a 0.15-Scale Model of the Hermes A-1E2 Missile at High Subsonic Mach Numbers

NASA Technical Reports Server (NTRS)

Alford, William J., Jr.

1952-01-01

The static longitudinal stability characteristics of a 0.15-scale model of the Hermes A-lE2 missile have been determined in the Langley high-speed 7- by 10-foot tunnel over a Mach number range of 0.50 to 0.98, corresponding to Reynolds numbers, based on body length, of 12.3 x 10(exp 6) to 17.1 x 10(exp 6). This paper presents results obtained with body alone and body-fins combinations at 0 degrees (one set of fins vertical and the other set horizontal) and 45 degree angle of roll. The results indicate that the addition of the fins to the body insures static longitudinal stability and provides essentially linear variations of the lift and pitching moment at small angles of attack throughout the Mach number range. The slopes of the lift and pitching-moment curves vary slightly with Mach number and show only small effects due to the angle of roll.

Scaling relation of the anomalous Hall effect in (Ga,Mn)As

NASA Astrophysics Data System (ADS)

Glunk, M.; Daeubler, J.; Schoch, W.; Sauer, R.; Limmer, W.

2009-09-01

We present magnetotransport studies performed on an extended set of (Ga,Mn)As samples at 4.2 K with longitudinal conductivities σxx ranging from the low-conductivity to the high-conductivity regime. The anomalous Hall conductivity σxy(AH) is extracted from the measured longitudinal and Hall resistivities. A transition from σxy(AH)=20Ω-1cm-1 due to the Berry phase effect in the high-conductivity regime to a scaling relation σxy(AH)∝σxx1.6 for low-conductivity samples is observed. This scaling relation is consistent with a recently developed unified theory of the anomalous Hall effect in the framework of the Keldysh formalism. It turns out to be independent of crystallographic orientation, growth conditions, Mn concentration, and strain, and can therefore be considered universal for low-conductivity (Ga,Mn)As. The relation plays a crucial role when deriving values of the hole concentration from magnetotransport measurements in low-conductivity (Ga,Mn)As. In addition, the hole diffusion constants for the high-conductivity samples are determined from the measured longitudinal conductivities.

Neuroimaging in aphasia treatment research: Consensus and practical guidelines for data analysis

PubMed Central

Meinzer, Marcus; Beeson, Pélagie M.; Cappa, Stefano; Crinion, Jenny; Kiran, Swathi; Saur, Dorothee; Parrish, Todd; Crosson, Bruce; Thompson, Cynthia K.

2012-01-01

Functional magnetic resonance imaging is the most widely used imaging technique to study treatment-induced recovery in post-stroke aphasia. The longitudinal design of such studies adds to the challenges researchers face when studying patient populations with brain damage in cross-sectional settings. The present review focuses on issues specifically relevant to neuroimaging data analysis in aphasia treatment research identified in discussions among international researchers at the Neuroimaging in Aphasia Treatment Research Workshop held at Northwestern University (Evanston, Illinois, USA). In particular, we aim to provide the reader with a critical review of unique problems related to the pre-processing, statistical modeling and interpretation of such data sets. Despite the fact that data analysis procedures critically depend on specific design features of a given study, we aim to discuss and communicate a basic set of practical guidelines that should be applicable to a wide range of studies and useful as a reference for researchers pursuing this line of research. PMID:22387474

Learning from Multiple Cases: A New Paradigm for Investigating the Effects of Clinical Experience on Knowledge Restructuring and Knowledge Acquisition.

ERIC Educational Resources Information Center

Boshuizen, Henny P. A.; Bongaerts, Maureen Machiels; van de Wiel, Margaretha W. J.; Schmidt, Henk G.

The effects of experience with a series of similar cases on the knowledge restructuring and learning from text were studied in a longitudinal design. Two groups of fourth-year medical students were confronted with a series of cases, part of them having the same underlying disease. The cases were interspersed with fillers, and each set of cases had…

The Permanent Secretary as Policy-Maker, Shaper, Taker, Sharer, and Resister in Education--Reflections on Sir James Hamilton as a Centralising Outsider

ERIC Educational Resources Information Center

Ribbins, Peter; Sherratt, Brian

2013-01-01

Given that elevation to permanent secretary is widely recognised as the apotheosis of a career in the Whitehall bureaucracy, it is remarkable that so few have been the subject of sustained biographical research and that this key role remains largely un-theorised. As such, this paper reports on aspects of a longitudinal study which set out to…

Everything under Control? The Effects of Age, Gender, and Education on Trajectories of Perceived Control in a Nationally Representative German Sample

ERIC Educational Resources Information Center

Specht, Jule; Egloff, Boris; Schmukle, Stefan C.

2013-01-01

Perceived control is an important variable for various demands involved in successful aging. However, perceived control is not set in stone but rather changes throughout the life course. The aim of this study was to identify cross-sectional age differences and longitudinal mean-level changes as well as rank-order changes in perceived control with…

Expression of Self-Concept and Adjustment against Repeated Aggressions: The Case of a Longitudinal Study on School Bullying

ERIC Educational Resources Information Center

Houbre, Barbara; Tarquinio, Cyril; Lanfranchi, Jean-Baptiste

2010-01-01

Bullying between students in the school setting is an increasing problem. Bullying can be defined as any form of repeated mental or physical violence carried out by one or several individuals on a person who is not capable of defending himself (Roland and Idsoe, "Aggress Behav" 27:446-462, 2001). The aim of this paper is to observe the expression…

Asthma Education and Intervention Program: Partnership for Asthma Trigger-Free Homes (PATH)

DTIC Science & Technology

2008-08-01

military setting if additional funding is procured.) 15. SUBJECT TERMS Asthma , longitudinal study, asthma education, indoor asthma triggers, dust...caregiver quality of life, we make use of the Juniper Pediatric Asthma Caregiver’s Quality of Life questionnaire (PACQLQ). It measures the problems that...whose reliability and validity are described below. We employ the Juniper Pediatric Asthma Caregiver’s Quality of Life questionnaire (PACQLQ) to measure

"Because if You Don't Put the Top On, It Will Spill": A Longitudinal Study of Sibling Teaching in Early Childhood

ERIC Educational Resources Information Center

Howe, Nina; Della Porta, Sandra; Recchia, Holly; Ross, Hildy

2016-01-01

Naturalistic dyadic sequences of teaching and learning involving older and younger siblings were investigated in 39 middle-class dyads over a 2-year period in early childhood. Siblings were observed during ongoing interactions in the home setting for 6 90-min sessions at both Time 1 (older sibling "M" age = 4.4 years; younger sibling…

Spanking and child development across the first decade of life.

PubMed

MacKenzie, Michael J; Nicklas, Eric; Waldfogel, Jane; Brooks-Gunn, Jeanne

2013-11-01

To examine the prevalence of maternal and paternal spanking of children at 3 and 5 years of age and the associations between spanking and children's externalizing behavior and receptive vocabulary through age 9. The Fragile Families and Child Well-Being Study, a longitudinal birth cohort study of children in 20 medium to large US cities, was used. Parental reports of spanking were assessed at age 3 and 5, along with child externalizing behavior and receptive vocabulary at age 9 (N = 1933). The data set also included an extensive set of child and family controls (including earlier measures of the child outcomes). Overall, 57% of mothers and 40% of fathers engaged in spanking when children were age 3, and 52% of mothers and 33% of fathers engaged in spanking at age 5. Maternal spanking at age 5, even at low levels, was associated with higher levels of child externalizing behavior at age 9, even after an array of risks and earlier child behavior were controlled for. Father's high-frequency spanking at age 5 was associated with lower child receptive vocabulary scores at age 9. Spanking remains a typical rearing experience for American children. These results demonstrate negative effects of spanking on child behavioral and cognitive development in a longitudinal sample from birth through 9 years of age.

[Resources and risks in old age: the LUCAS-I marker set for a classification of elderly people as fit, pre-frail and frail. First results on validity from the Longitudinal Urban Cohort Ageing Study (LUCAS), Hamburg].

PubMed

Dapp, U; Anders, J; Golgert, S; von Renteln-Kruse, W; Minder, C E

2012-06-01

There is a need for a simple self-administered instrument to assess frailty in community-dwelling seniors. We present a new marker set to assess the functional state of seniors. Contrary to current literature, we focus not only on risks, but also include resources. The questions relate to facts (ways to do things), rather than on subjective information (e.g. exhaustion). It was developed in the context of the Longitudinal Urban Cohort Ageing Study (LUCAS) in Hamburg, Germany. The classification based on these questions proposes operational definitions of the terms fit, pre-frail and frail and is predictive for need for nursing care as well as mortality. A wealth of results establishes the validity of the categorisation compared to other health questions. One of the classification questions concerns cycling. For areas where cycling is not suitable, we propose to replace this question with one about independently walking 500 m. However, the cycling question appears to indicate frailty earlier. The self-administered questionnaire provides a simple, cost-effective way to screen seniors for early signs of declining function in order to start preventive action.

Rural Compared to Urban Home Community Settings as Predictors of First-Year Students' Adjustment to University

ERIC Educational Resources Information Center

Ames, Megan E.; Wintre, Maxine G.; Prancer, S. Mark; Pratt, Michael W.; Birnie-Lefcovitch, Shelly; Polivy, Janet; Adams, Gerald R.

2014-01-01

Undergraduates (N = 2,823) at 6 universities were surveyed longitudinally to examine the relevance of student home setting on the transition to university. Preliminary results indicated that rural students seem less likely to attend large, ethnically diverse universities. Hierarchical linear models revealed that "proximal rural" students…

Multilevel Latent Class Analysis: Parametric and Nonparametric Models

ERIC Educational Resources Information Center

Finch, W. Holmes; French, Brian F.

2014-01-01

Latent class analysis is an analytic technique often used in educational and psychological research to identify meaningful groups of individuals within a larger heterogeneous population based on a set of variables. This technique is flexible, encompassing not only a static set of variables but also longitudinal data in the form of growth mixture…

Recruitment and retention strategies in longitudinal clinical studies with low-income populations.

PubMed

Nicholson, Lisa M; Schwirian, Patricia M; Klein, Elizabeth G; Skybo, Theresa; Murray-Johnson, Lisa; Eneli, Ihuoma; Boettner, Bethany; French, Gina M; Groner, Judith A

2011-05-01

Conducting longitudinal research studies with low-income and/or minority participants present a unique set of challenges and opportunities. To outline the specific strategies employed to successfully recruit and retain participants in a longitudinal study of nutritional anticipatory guidance during early childhood, conducted with a low-income, ethnically diverse, urban population of mothers. We describe recruitment and retention efforts made by the research team for the 'MOMS' Study (Making Our Mealtimes Special). The 'multilayered' approach for recruitment and retention included commitment of research leadership, piloting procedures, frequent team reporting, emphasis on participant convenience, incentives, frequent contact with participants, expanded budget, clinical staff buy-in, a dedicated phone line, and the use of research project branding and logos. Barriers to enrollment were not encountered in this project, despite recruiting from a low-income population with a large proportion of African-American families. Process evaluation with clinic staff demonstrated the perception of the MOMS staff was very positive. Participant retention rate was 75% and 64% at 6 months and 12 months post-recruitment, respectively. We attribute retention success largely to a coordinated effort between the research team and the infrastructure support at the clinical sites, as well as project branding and a dedicated phone line. Successful participant recruitment and retention approaches need to be specific and consistent with clinical staff buy in throughout the project. Published by Elsevier Inc.

Longitudinal On-Column Thermal Modulation for Comprehensive Two-Dimensional Liquid Chromatography.

PubMed

Creese, Mari E; Creese, Mathew J; Foley, Joe P; Cortes, Hernan J; Hilder, Emily F; Shellie, Robert A; Breadmore, Michael C

2017-01-17

Longitudinal on-column thermal modulation for comprehensive two-dimensional liquid chromatography is introduced. Modulation optimization involved a systematic investigation of heat transfer, analyte retention, and migration velocity at a range of temperatures. Longitudinal on-column thermal modulation was realized using a set of alkylphenones and compared to a conventional valve-modulator employing sample loops. The thermal modulator showed a reduced modulation-induced pressure impact than valve modulation, resulting in reduced baseline perturbation by a factor of 6; yielding a 6-14-fold improvement in signal-to-noise. A red wine sample was analyzed to demonstrate the potential of the longitudinal on-column thermal modulator for separation of a complex sample. Discrete peaks in the second dimension using the thermal modulator were 30-55% narrower than with the valve modulator. The results shown herein demonstrate the benefits of an active focusing modulator, such as reduced detection limits and increased total peak capacity.

Spatiotemporal historical datasets at micro-level for geocoded individuals in five Swedish parishes, 1813–1914

PubMed Central

Hedefalk, Finn; Svensson, Patrick; Harrie, Lars

2017-01-01

This paper presents datasets that enable historical longitudinal studies of micro-level geographic factors in a rural setting. These types of datasets are new, as historical demography studies have generally failed to properly include the micro-level geographic factors. Our datasets describe the geography over five Swedish rural parishes, and by linking them to a longitudinal demographic database, we obtain a geocoded population (at the property unit level) for this area for the period 1813–1914. The population is a subset of the Scanian Economic Demographic Database (SEDD). The geographic information includes the following feature types: property units, wetlands, buildings, roads and railroads. The property units and wetlands are stored in object-lifeline time representations (information about creation, changes and ends of objects are recorded in time), whereas the other feature types are stored as snapshots in time. Thus, the datasets present one of the first opportunities to study historical spatio-temporal patterns at the micro-level. PMID:28398288

Improvements in HIV treatment outcomes among indigenous and non-indigenous people who use illicit drugs in a Canadian setting

PubMed Central

Milloy, M-J; King, Alexandra; Kerr, Thomas; Adams, Evan; Samji, Hasina; Guillemi, Silvia; Wood, Evan; Montaner, Julio

2016-01-01

Introduction In many settings worldwide, members of indigenous groups experience a disproportionate burden of HIV. In Canada, there is an urgent need to improve HIV treatment outcomes for indigenous people living with HIV (IPLWH), to not only reduce HIV/AIDS-associated morbidity and mortality but also curb elevated rates of viral transmission. Thus, by comparing indigenous and non-indigenous participants in an ongoing longitudinal cohort of HIV-positive people who use illicit drugs, we sought to investigate longitudinal changes in three HIV treatment indicators for IPLWH who use illicit drugs during a community-wide treatment-as-prevention (TasP) initiative in British Columbia, Canada. Methods We used data from the ACCESS study, an ongoing observational prospective cohort of HIV-positive illicit drug users recruited from community settings in Vancouver, British Columbia. Cohort data are linked to comprehensive retrospective and prospective clinical records in a setting of no-cost HIV/AIDS treatment and care. We used multivariable generalized estimating equations (GEE) to evaluate longitudinal changes in the proportion of participants with exposure to antiretroviral therapy (ART) in the previous 180 days, optimal adherence to ART (i.e. ≥95% vs. <95%) and non-detectable HIV-1 RNA viral load (VL <50 copies/mL plasma). Results Between 2005 and 2014, 845 individuals were recruited, including 326 (39%) self-reporting any indigenous ancestry, and contributed 6732 interviews and 13,495 VL measurements. Among indigenous participants, the proportion with recent ART increased from 51 to 94% and non-detectable VL from 23 to 65%. In multivariable models, later interview period was positively associated with recent ART (adjusted odds ratio (AOR)=1.16 per interview period, 95% confidence interval (CI): 1.11 to 1.20) and non-detectable VL (AOR=1.07, 95% CI: 1.04 to 1.10). In adjusted models comparing indigenous and non-indigenous participants, we did not observe differences between the two groups (all p>0.1). Conclusions In this large and long-term study involving community-recruited HIV-positive illicit drug users, we observed a substantial and increasing proportion of indigenous participants reach several important thresholds in HIV care at rates indistinguishable from non-indigenous participants. The current findings highlight the important role of TasP on vulnerable populations in this setting and contribute to the evidence base supporting the immediate scale-up of ART to address HIV/AIDS-associated morbidity, mortality and viral transmission. PMID:27094914

Improvements in HIV treatment outcomes among indigenous and non-indigenous people who use illicit drugs in a Canadian setting.

PubMed

Milloy, M-J; King, Alexandra; Kerr, Thomas; Adams, Evan; Samji, Hasina; Guillemi, Silvia; Wood, Evan; Montaner, Julio

2016-01-01

In many settings worldwide, members of indigenous groups experience a disproportionate burden of HIV. In Canada, there is an urgent need to improve HIV treatment outcomes for indigenous people living with HIV (IPLWH), to not only reduce HIV/AIDS-associated morbidity and mortality but also curb elevated rates of viral transmission. Thus, by comparing indigenous and non-indigenous participants in an ongoing longitudinal cohort of HIV-positive people who use illicit drugs, we sought to investigate longitudinal changes in three HIV treatment indicators for IPLWH who use illicit drugs during a community-wide treatment-as-prevention (TasP) initiative in British Columbia, Canada. We used data from the ACCESS study, an ongoing observational prospective cohort of HIV-positive illicit drug users recruited from community settings in Vancouver, British Columbia. Cohort data are linked to comprehensive retrospective and prospective clinical records in a setting of no-cost HIV/AIDS treatment and care. We used multivariable generalized estimating equations (GEE) to evaluate longitudinal changes in the proportion of participants with exposure to antiretroviral therapy (ART) in the previous 180 days, optimal adherence to ART (i.e. ≥ 95% vs. < 95%) and non-detectable HIV-1 RNA viral load (VL <50 copies/mL plasma). Between 2005 and 2014, 845 individuals were recruited, including 326 (39%) self-reporting any indigenous ancestry, and contributed 6732 interviews and 13,495 VL measurements. Among indigenous participants, the proportion with recent ART increased from 51 to 94% and non-detectable VL from 23 to 65%. In multivariable models, later interview period was positively associated with recent ART (adjusted odds ratio (AOR) = 1.16 per interview period, 95% confidence interval (CI): 1.11 to 1.20) and non-detectable VL (AOR = 1.07, 95% CI: 1.04 to 1.10). In adjusted models comparing indigenous and non-indigenous participants, we did not observe differences between the two groups (all p>0.1). In this large and long-term study involving community-recruited HIV-positive illicit drug users, we observed a substantial and increasing proportion of indigenous participants reach several important thresholds in HIV care at rates indistinguishable from non-indigenous participants. The current findings highlight the important role of TasP on vulnerable populations in this setting and contribute to the evidence base supporting the immediate scale-up of ART to address HIV/AIDS-associated morbidity, mortality and viral transmission.

Healthcare utilization in older patients using personal emergency response systems: an analysis of electronic health records and medical alert data : Brief Description: A Longitudinal Retrospective Analyses of healthcare utilization rates in older patients using Personal Emergency Response Systems from 2011 to 2015.

PubMed

Agboola, Stephen; Golas, Sara; Fischer, Nils; Nikolova-Simons, Mariana; Op den Buijs, Jorn; Schertzer, Linda; Kvedar, Joseph; Jethwani, Kamal

2017-04-18

Personal Emergency Response Systems (PERS) are traditionally used as fall alert systems for older adults, a population that contributes an overwhelming proportion of healthcare costs in the United States. Previous studies focused mainly on qualitative evaluations of PERS without a longitudinal quantitative evaluation of healthcare utilization in users. To address this gap and better understand the needs of older patients on PERS, we analyzed longitudinal healthcare utilization trends in patients using PERS through the home care management service of a large healthcare organization. Retrospective, longitudinal analyses of healthcare and PERS utilization records of older patients over a 5-years period from 2011-2015. The primary outcome was to characterize the healthcare utilization of PERS patients. This outcome was assessed by 30-, 90-, and 180-day readmission rates, frequency of principal admitting diagnoses, and prevalence of conditions leading to potentially avoidable admissions based on Centers for Medicare and Medicaid Services classification criteria. The overall 30-day readmission rate was 14.2%, 90-days readmission rate was 34.4%, and 180-days readmission rate was 42.2%. While 30-day readmission rates did not increase significantly (p = 0.16) over the study period, 90-days (p = 0.03) and 180-days (p = 0.04) readmission rates did increase significantly. The top 5 most frequent principal diagnoses for inpatient admissions included congestive heart failure (5.7%), chronic obstructive pulmonary disease (4.6%), dysrhythmias (4.3%), septicemia (4.1%), and pneumonia (4.1%). Additionally, 21% of all admissions were due to conditions leading to potentially avoidable admissions in either institutional or non-institutional settings (16% in institutional settings only). Chronic medical conditions account for the majority of healthcare utilization in older patients using PERS. Results suggest that PERS data combined with electronic medical records data can provide useful insights that can be used to improve health outcomes in older patients.

Association of Combined Patterns of Tobacco and Cannabis Use in Adolescence With Psychotic Experiences

PubMed Central

Gage, Suzanne H.; Heron, Jon; Hickman, Matthew; Lewis, Glyn; Munafò, Marcus R.; Zammit, Stanley

2018-01-01

Importance There is concern about potentially causal effects of tobacco use on psychosis, but epidemiological studies have been less robust in attempts to minimize effects of confounding than studies of cannabis use have been. Objectives To examine the association of patterns of cigarette and cannabis use with preceding and subsequent psychotic experiences, and to compare effects of confounding across these patterns. Design, Setting, and Participants This cohort study used data from the Avon Longitudinal Study of Parents and Children, which initially consisted of 14 062 children. Data were collected periodically from September 6, 1990, with collection ongoing, and analyzed from August 8, 2016, through June 14, 2017. Cigarette and cannabis use data were summarized using longitudinal latent class analysis to identify longitudinal classes of substance use. Associations between classes and psychotic experiences at age 18 years were assessed. Exposures Depending on the analysis model, exposures were longitudinal classes of substance use or psychotic experiences at age 12 years. Main Outcomes and Measures Logistic regression was used to examine the associations between substance use longitudinal classes and subsequent onset of psychotic experiences. Results Longitudinal classes were derived using 5300 participants (56.1% female) who had at least 3 measures of cigarette and cannabis use from ages 14 to 19 years. Prior to adjusting for a range of potential confounders, there was strong evdience that early-onset cigarette-only use (4.3%), early-onset cannabis use (3.2%), and late-onset cannabis use (11.9%) (but not later-onset cigarette-only use [14.8%]) latent classes were associated with increased psychotic experiences compared with nonusers (65.9%) (omnibus P < .001). After adjusting for confounders, the association for early-onset cigarette-only use attenuated substantially (unadjusted odds ratio [OR], 3.03; 95% CI, 1.13-8.14; adjusted OR, 1.78; 95% CI, 0.54-5.88), whereas those for early-onset cannabis use (adjusted OR, 3.70; 95% CI, 1.66-8.25) and late-onset cannabis use (adjusted OR, 2.97; 95% CI, 1.63-5.40) remained consistent. Conclusions and Relevance In this study, our findings indicate that while individuals who use cannabis or cigarettes during adolescence have an increased risk of subsequent psychotic experiences, epidemiological evidence is substantively more robust for cannabis use than it is for tobacco use. PMID:29344610

Assessing Patient Activation among High-Need, High-Cost Patients in Urban Safety Net Care Settings.

PubMed

Napoles, Tessa M; Burke, Nancy J; Shim, Janet K; Davis, Elizabeth; Moskowitz, David; Yen, Irene H

2017-12-01

We sought to examine the literature using the Patient Activation Measure (PAM) or the Patient Enablement Instrument (PEI) with high-need, high-cost (HNHC) patients receiving care in urban safety net settings. Urban safety net care management programs serve low-income, racially/ethnically diverse patients living with multiple chronic conditions. Although many care management programs track patient progress with the PAM or the PEI, it is not clear whether the PAM or the PEI is an effective and appropriate tool for HNHC patients receiving care in urban safety net settings in the United States. We searched PubMed, EMBASE, Web of Science, and PsycINFO for articles published between 2004 and 2015 that used the PAM and between 1998 and 2015 that used the PEI. The search was limited to English-language articles conducted in the United States and published in peer-reviewed journals. To assess the utility of the PAM and the PEI in urban safety net care settings, we defined a HNHC patient sample as racially/ethnically diverse, low socioeconomic status (SES), and multimorbid. One hundred fourteen articles used the PAM. All articles using the PEI were conducted outside the U.S. and therefore were excluded. Nine PAM studies (8%) included participants similar to those receiving care in urban safety net settings, three of which were longitudinal. Two of the three longitudinal studies reported positive changes following interventions. Our results indicate that research on patient activation is not commonly conducted on racially and ethnically diverse, low SES, and multimorbid patients; therefore, there are few opportunities to assess the appropriateness of the PAM in such populations. Investigators expressed concerns with the potential unreliability and inappropriate nature of the PAM on multimorbid, older, and low-literacy patients. Thus, the PAM may not be able to accurately assess patient progress among HNHC patients receiving care in urban safety net settings. Assessing progress in the urban safety net care setting requires measures that account for the social and structural challenges and competing demands of HNHC patients.

Exploring the success of an integrated primary care partnership: a longitudinal study of collaboration processes.

PubMed

Valentijn, Pim P; Vrijhoef, Hubertus J M; Ruwaard, Dirk; de Bont, Antoinette; Arends, Rosa Y; Bruijnzeels, Marc A

2015-01-22

Forming partnerships is a prominent strategy used to promote integrated service delivery across health and social service systems. Evidence about the collaboration process upon which partnerships evolve has rarely been addressed in an integrated-care setting. This study explores the longitudinal relationship of the collaboration process and the influence on the final perceived success of a partnership in such a setting. The collaboration process through which partnerships evolve is based on a conceptual framework which identifies five themes: shared ambition, interests and mutual gains, relationship dynamics, organisational dynamics and process management. Fifty-nine out of 69 partnerships from a national programme in the Netherlands participated in this survey study. At baseline, 338 steering committee members responded, and they returned 320 questionnaires at follow-up. Multiple-regression-analyses were conducted to explore the relationship between the baseline as well as the change in the collaboration process and the final success of the partnerships. Mutual gains and process management were the most significant baseline predictors for the final success of the partnership. A positive change in the relationship dynamics had a significant effect on the final success of a partnership. Insight into the collaboration process of integrated primary care partnerships offers a potentially powerful way of predicting their success. Our findings underscore the importance of monitoring the collaboration process during the development of the partnerships in order to achieve their full collaborative advantage.

Transformative Use of an Improved All-Payer Hospital Discharge Data Infrastructure for Community-Based Participatory Research: A Sustainability Pathway

PubMed Central

Salemi, Jason L; Salinas-Miranda, Abraham A; Wilson, Roneé E; Salihu, Hamisu M

2015-01-01

Objective To describe the use of a clinically enhanced maternal and child health (MCH) database to strengthen community-engaged research activities, and to support the sustainability of data infrastructure initiatives. Data Sources/Study Setting Population-based, longitudinal database covering over 2.3 million mother–infant dyads during a 12-year period (1998–2009) in Florida. Setting: A community-based participatory research (CBPR) project in a socioeconomically disadvantaged community in central Tampa, Florida. Study Design Case study of the use of an enhanced state database for supporting CBPR activities. Principal Findings A federal data infrastructure award resulted in the creation of an MCH database in which over 92 percent of all birth certificate records for infants born between 1998 and 2009 were linked to maternal and infant hospital encounter-level data. The population-based, longitudinal database was used to supplement data collected from focus groups and community surveys with epidemiological and health care cost data on important MCH disparity issues in the target community. Data were used to facilitate a community-driven, decision-making process in which the most important priorities for intervention were identified. Conclusions Integrating statewide all-payer, hospital-based databases into CBPR can empower underserved communities with a reliable source of health data, and it can promote the sustainability of newly developed data systems. PMID:25879276

The association between personal income and aging: A population-based 13-year longitudinal study.

PubMed

Lin, Tzu-Yu; Chen, Chia-Yu; Tsao, Chueh-Yung; Hsu, Kuang-Hung

Population aging is set to increase the elder dependency ratio, causing a rapid increase in healthcare expenditures and financial burden on the government. This study aims to construct an aging score from age-related diseases and to perform longitudinal analyses to examine the association between personal income and aging. A total of 86,838 subjects drawn from a community with 384,617 residents in northern Taiwan were examined. Personal income and aging-related diseases were measured from the National Health Insurance database during 1997-2010. Multiple linear regression and stratified analyses were used. Our results indicate that subjects with low personal income (defined as monthly income ≤610 USD) can have high aging scores as calculated by selected aging-related diseases. In stratified analyses, moreover, subjects with low personal income tended to have higher aging scores across different anthropometric groups. The association was particularly evident in subjects >60years old, and they were noted across multiple strata, including those of catastrophic illness as well as type of primary care setting. This study found evidence for association between low income and aging in a population with compulsory health insurance program, where accessibility barriers were low in terms of health care resources and personal socioeconomic status. The economic inequity causes difference in aging process, which deserves for future interventions. Copyright © 2017 Elsevier B.V. All rights reserved.

Monitoring training response in young Friesian dressage horses using two different standardised exercise tests (SETs).

PubMed

de Bruijn, Cornelis Marinus; Houterman, Willem; Ploeg, Margreet; Ducro, Bart; Boshuizen, Berit; Goethals, Klaartje; Verdegaal, Elisabeth-Lidwien; Delesalle, Catherine

2017-02-14

Most Friesian horses reach their anaerobic threshold during a standardized exercise test (SET) which requires lower intensity exercise than daily routine training. to study strengths and weaknesses of an alternative SET-protocol. Two different SETs (SETA and SETB) were applied during a 2 month training period of 9 young Friesian dressage horses. SETB alternated short episodes of canter with trot and walk, lacking long episodes of cantering, as applied in SETA. Following parameters were monitored: blood lactic acid (BLA) after cantering, average heart rate (HR) in trot and maximum HR in canter. HR and BLA of SETA and SETB were analyzed using a paired two-sided T-test and Spearman Correlation-coefficient (p* < 0.05). BLA after cantering was significantly higher in SETA compared to SETB and maximum HR in canter was significantly higher in SETA compared to SETB. The majority of horses showed a significant training response based upon longitudinal follow-up of BLA. Horses with the lowest fitness at start, displayed the largest training response. BLA was significantly lower in week 8 compared to week 0, in both SETA and SETB. A significantly decreased BLA level after cantering was noticeable in week 6 in SETA, whereas in SETB only as of week 8. In SETA a very strong correlation for BLA and average HR at trot was found throughout the entire training period, not for canter. Young Friesian horses do reach their anaerobic threshold during a SET which requires lower intensity than daily routine training. Therefore close monitoring throughout training is warranted. Longitudinal follow up of BLA and not of HR is suitable to assess training response. In the current study, horses that started with the lowest fitness level, showed the largest training response. During training monitoring HR in trot rather than in canter is advised. SETB is best suited as a template for daily training in the aerobic window.

Redesign of a Variable-Gain Output Feedback Longitudinal Controller Flown on the High-Alpha Research Vehicle (HARV)

NASA Technical Reports Server (NTRS)

Ostroff, Aaron J.

1998-01-01

This paper describes a redesigned longitudinal controller that flew on the High-Alpha Research Vehicle (HARV) during calendar years (CY) 1995 and 1996. Linear models are developed for both the modified controller and a baseline controller that was flown in CY 1994. The modified controller was developed with three gain sets for flight evaluation, and several linear analysis results are shown comparing the gain sets. A Neal-Smith flying qualities analysis shows that performance for the low- and medium-gain sets is near the level 1 boundary, depending upon the bandwidth assumed, whereas the high-gain set indicates a sensitivity problem. A newly developed high-alpha Bode envelope criterion indicates that the control system gains may be slightly high, even for the low-gain set. A large motion-base simulator in the United Kingdom was used to evaluate the various controllers. Desired performance, which appeared to be satisfactory for flight, was generally met with both the low- and medium-gain sets. Both the high-gain set and the baseline controller were very sensitive, and it was easy to generate pilot-induced oscillation (PIO) in some of the target-tracking maneuvers. Flight target-tracking results varied from level 1 to level 3 and from no sensitivity to PIO. These results were related to pilot technique and whether actuator rate saturation was encountered.

NUCLEAR REACTOR FUEL ELEMENT ASSEMBLY

DOEpatents

Stengel, F.G.

1963-12-24

A method of fabricating nuclear reactor fuel element assemblies having a plurality of longitudinally extending flat fuel elements in spaced parallel relation to each other to form channels is presented. One side of a flat side plate is held contiguous to the ends of the elements and a welding means is passed along the other side of the platertransverse to the direction of the longitudinal extension of the elements. The setting and speed of travel of the welding means is set to cause penetration of the side plate with welds at bridge the gap in each channel between adjacent fuel elements with a weld-through bubble of predetermined size. The fabrication of a high strength, dependable fuel element is provided, and the reduction of distortion and high production costs are facilitated by this method. (AEC)

Making Teamwork Work: Team Knowledge for Team Effectiveness.

PubMed

Guchait, Priyanko; Lei, Puiwa; Tews, Michael J

2016-01-01

This study examined the impact of two types of team knowledge on team effectiveness. The study assessed the impact of taskwork knowledge and teamwork knowledge on team satisfaction and performance. A longitudinal study was conducted with 27 service-management teams involving 178 students in a real-life restaurant setting. Teamwork knowledge was found to impact both team outcomes. Furthermore, team learning behavior was found to mediate the relationships between teamwork knowledge and team outcomes. Educators and managers should therefore ensure these types of knowledge are developed in teams along with learning behavior for maximum effectiveness.

Corneal endothelial morphology and function after torsional and longitudinal ultrasound mode phacoemulsification

PubMed Central

Módis, László Jr.; Szalai, Eszter; Flaskó, Zsuzsa; Németh, Gábor

2016-01-01

Purpose. To study the endothelial cell morphology and corneal thickness changes after phacoemulsification by using the OZil torsional and longitudinal ultrasound techniques (Infiniti Vision System, Alcon Laboratories). Setting. Department of Ophthalmology, Clinical Center, University of Debrecen, Debrecen, Hungary. Methods. 52 patients with cataract were randomly assigned to longitudinal ultrasound and torsional mode group. All surgeries were performed through a 2.2 mm clear corneal incision, the method employed being divide and conquer. The endothelial morphometry such as cell density (ECD), mean cell area, coefficient of variation of cell area, and central corneal thickness were examined with specular microscopy (EM-1000, Tomey) preoperatively and 4, 8 weeks postoperatively. Results. ECD values decreased significantly in both surgical groups (P < .001, repeated- mesures ANOVA), the postoperative endothelial cell loss was higher in the longitudinal ultrasound mode group (3.5% and 6.5%, at 4 and 8 weeks after surgery) than in the torsional group (3.3% and 5.5%, at 4 and 8 weeks after surgery), the difference not being significant between the two groups (P = .164 and P = .479, at 4 and 8 weeks after surgery, Mann-Whitney test). There was no statistically significant difference in any of the assessed parameters between the two surgical groups (P > .05). No significant correlation was found between the endothelial cell loss and the nucleus density. Conclusions. Both phacoemulsification techniques were safe and effective. The torsional handpiece performs oscillatory movements and delivers less energy into the eye than the longitudinal ultrasound technique, therefore providing more favorable energy and thermal safety profile. PMID:29450332

LONGITUDINAL FOLLOW-UP OF LATE-ONSET ALZHEIMER DISEASE FAMILIES

PubMed Central

Carney, R.M.; Slifer, M.A.; Lin, P.I.; Gaskell, P. C.; Scott, W. K.; Potocky, C.F.; Hulette, C. M.; Welsh-Bohmer, K. A.; Schmechel, D. E.; Vance, J.M.; Pericak-Vance, M. A.

2009-01-01

Historically, data for genetic studies are collected at one time point. However, for diseases with late onset or with complex phenotypes, such as Alzheimer disease (AD), restricting diagnosis to a single ascertainment contact may not be sufficient. Affection status may change over time, and some initial diagnoses may be inconclusive. Follow-up provides the opportunity to resolve these complications. However, to date, previous studies have not formally demonstrated that longitudinally re-contacting families is practical or productive. To update data initially collected for linkage analysis of late-onset Alzheimer disease (LOAD), we successfully re-contacted 63 of 81 (78%) multiplex families (two to 17 years after ascertainment). Clinical status changed for 73 of the 230 (32%) non-affected participants. Additionally, expanded family history identified 20 additional affected individuals to supplement the data set. Furthermore, fostering ongoing relationships with participating families helped recruit 101 affected participants into an autopsy and tissue donation program. Despite similar presentations, discordance between clinical diagnosis and neuropathologic diagnosis was observed in 28% of those with tissue diagnoses. Most of the families were successfully re-contacted, and significant refinement and supplementation of the data was achieved. We concluded that serial contact with longitudinal evaluation of families has significant implications for genetic analyses. PMID:18361431

Enhancing the stabilization of aircraft pitch motion control via intelligent and classical method

NASA Astrophysics Data System (ADS)

Lukman, H.; Munawwarah, S.; Azizan, A.; Yakub, F.; Zaki, S. A.; Rasid, Z. A.

2017-12-01

The pitching movement of an aircraft is very important to ensure passengers are intrinsically safe and the aircraft achieve its maximum stability. The equations governing the motion of an aircraft are a complex set of six nonlinear coupled differential equations. Under certain assumptions, it can be decoupled and linearized into longitudinal and lateral equations. Pitch control is a longitudinal problem and thus, only the longitudinal dynamics equations are involved in this system. It is a third order nonlinear system, which is linearized about the operating point. The system is also inherently unstable due to the presence of a free integrator. Because of this, a feedback controller is added in order to solve this problem and enhance the system performance. This study uses two approaches in designing controller: a conventional controller and an intelligent controller. The pitch control scheme consists of proportional, integral and derivatives (PID) for conventional controller and fuzzy logic control (FLC) for intelligent controller. Throughout the paper, the performance of the presented controllers are investigated and compared based on the common criteria of step response. Simulation results have been obtained and analysed by using Matlab and Simulink software. The study shows that FLC controller has higher ability to control and stabilize the aircraft's pitch angle as compared to PID controller.

A Hot-Deck Multiple Imputation Procedure for Gaps in Longitudinal Recurrent Event Histories

PubMed Central

Wang, Chia-Ning; Little, Roderick; Nan, Bin; Harlow, Siobán D.

2012-01-01

Summary We propose a regression-based hot deck multiple imputation method for gaps of missing data in longitudinal studies, where subjects experience a recurrent event process and a terminal event. Examples are repeated asthma episodes and death, or menstrual periods and the menopause, as in our motivating application. Research interest concerns the onset time of a marker event, defined by the recurrent-event process, or the duration from this marker event to the final event. Gaps in the recorded event history make it difficult to determine the onset time of the marker event, and hence, the duration from onset to the final event. Simple approaches such as jumping gap times or dropping cases with gaps have obvious limitations. We propose a procedure for imputing information in the gaps by substituting information in the gap from a matched individual with a completely recorded history in the corresponding interval. Predictive Mean Matching is used to incorporate information on longitudinal characteristics of the repeated process and the final event time. Multiple imputation is used to propagate imputation uncertainty. The procedure is applied to an important data set for assessing the timing and duration of the menopausal transition. The performance of the proposed method is assessed by a simulation study. PMID:21361886

Predictive Modeling of K-12 Academic Outcomes: A Primer for Researchers Working with Education Data

ERIC Educational Resources Information Center

Porter, Kristin E.; Balu, Rekha

2016-01-01

Education systems are increasingly creating rich, longitudinal data sets with frequent, and even real-time, data updates of many student measures, including daily attendance, homework submissions, and exam scores. These data sets provide an opportunity for district and school staff members to move beyond an indicators-based approach and instead…

The Creation and Development of an Interest Group: Life at the Intersection of Big Business and Education Reform.

ERIC Educational Resources Information Center

Sipple, John W.; Miskel, Cecil G.; Matheney, Timothy M.; Kearney, C. Philip

1997-01-01

Since business leaders have become increasingly involved in setting education reform agendas, understanding their motives would be helpful. Using five interest-group theories and longitudinal data, this article examines the formation, agenda setting, and maintenance of an organization of business leaders. Moderate support was found for each…

TRAJECTORIES OF ACCULTURATION AND ENCULTURATION IN RELATION TO HEAVY EPISODIC DRINKING AND MARIJUANA USE IN A SAMPLE OF MEXICAN AMERICAN SERIOUS JUVENILE OFFENDERS

PubMed Central

Losoya, Sandra H.; Knight, George P.; Chassin, Laurie; Little, Michelle; Vargas-Chanes, Delfino; Mauricio, Anne; Piquero, Alex

2009-01-01

This study examines the longitudinal relations of multiple dimensions of acculturation and enculturation to heavy episodic drinking and marijuana use in a sample of 300 male, Mexican-American, serious juvenile offenders. We track trajectories between ages 15 and 20 and also consider the effects of participants’ time spent residing in supervised settings during these years. Results showed some (although not entirely consistent) support for the hypothesis that bicultural adaptation is most functional in terms of lowered substance use involvement. The current findings demonstrate the importance of examining these relations longitudinally and among multiple dimensions of acculturation and enculturation, and they call into question simple models that suggest that greater acculturation is associated with greater substance use among Mexican-American adolescents. PMID:20198119

STORY AND HISTORY IN FETAL BEHAVIOR RESEARCH.

PubMed

Brakke, Karen

2015-09-01

In their monograph, DiPietro, Costigan, and Voegtline present an important and thoughtful portrait of low-risk fetal development during the last trimester of gestation, and they also pay tribute to the Fels Longitudinal Study investigators' early work in this area. In this commentary, the history and legacy of the Fels Institute is further explored within the broader context of fetal research, and DiPietro et al.'s findings are placed in alignment with contemporary dynamic systems' theoretical approaches that emphasize longitudinal analysis of emergent behavior and process during early development. The commentary puts forth the assertion that the work reported by DiPietro and her colleagues tells a story that sets the stage for a new generation of technology-enhanced and culturally expanded investigations of fetal behavior. © 2015 The Society for Research in Child Development, Inc.

Longitudinal histories as predictors of future diagnoses of domestic abuse: modelling study

PubMed Central

Kohane, Isaac S; Mandl, Kenneth D

2009-01-01

Objective To determine whether longitudinal data in patients’ historical records, commonly available in electronic health record systems, can be used to predict a patient’s future risk of receiving a diagnosis of domestic abuse. Design Bayesian models, known as intelligent histories, used to predict a patient’s risk of receiving a future diagnosis of abuse, based on the patient’s diagnostic history. Retrospective evaluation of the model’s predictions using an independent testing set. Setting A state-wide claims database covering six years of inpatient admissions to hospital, admissions for observation, and encounters in emergency departments. Population All patients aged over 18 who had at least four years between their earliest and latest visits recorded in the database (561 216 patients). Main outcome measures Timeliness of detection, sensitivity, specificity, positive predictive values, and area under the ROC curve. Results 1.04% (5829) of the patients met the narrow case definition for abuse, while 3.44% (19 303) met the broader case definition for abuse. The model achieved sensitive, specific (area under the ROC curve of 0.88), and early (10-30 months in advance, on average) prediction of patients’ future risk of receiving a diagnosis of abuse. Analysis of model parameters showed important differences between sexes in the risks associated with certain diagnoses. Conclusions Commonly available longitudinal diagnostic data can be useful for predicting a patient’s future risk of receiving a diagnosis of abuse. This modelling approach could serve as the basis for an early warning system to help doctors identify high risk patients for further screening. PMID:19789406

Childhood Precursors of the Narcissistic Personality.

PubMed

Cramer, Phebe

2017-09-01

This research identifies the childhood personality characteristics that predict the presence of narcissism in adulthood. Using data from the longitudinal study of Block and Block (The California Child Q-set. Palo Alto, CA: Consulting Psychologists Press, 1980), childhood personality characteristics were assessed at age 11 (N = 100) using the California Child Q-set. A number of these were shown to differentially predict the presence of grandiose or vulnerable narcissism at age 23. Factor analyses of the Child Q-set items showed that the presence of Grandiose Narcissism was positively related to childhood factors representing social presence and negatively related to planfulness. In contrast, vulnerable narcissism was positively related to childhood impulsivity and negatively related to stable self-esteem. Both types of narcissism were positively related to childhood factors representing need for control.

Idiopathic inflammatory myositis.

PubMed

Tieu, Joanna; Lundberg, Ingrid E; Limaye, Vidya

2016-02-01

Knowledge on idiopathic inflammatory myopathy (IIM) has evolved with the identification of myositis-associated and myositis-specific antibodies, development of histopathological classification and the recognition of how these correlate with clinical phenotype and response to therapy. In this paper, we outline key advances in diagnosis and histopathology, including the more recent identification of antibodies associated with immune-mediated necrotising myopathy (IMNM) and inclusion body myositis (IBM). Ongoing longitudinal observational cohorts allow further classification of these patients with IIM, their predicted clinical course and response to specific therapies. Registries have been developed worldwide for this purpose. A challenging aspect in IIM, a multisystem disease with multiple clinical subtypes, has been defining disease status and clinically relevant improvement. Tools for assessing activity and damage are now recognised to be important in determining disease activity and guiding therapeutic decision-making. The International Myositis Assessment and Clinical Studies (IMACS) group has developed such tools for use in research and clinical settings. There is limited evidence for specific treatment strategies in IIM. With significant development in the understanding of IIM and improved classification, longitudinal observational cohorts and trials using validated outcome measures are necessary, to provide important information for evidence-based care in the clinical setting. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Colorimetric and Longitudinal Analysis of Leukocoria in Recreational Photographs of Children with Retinoblastoma

PubMed Central

Holden, Rebecca L.; Shaw, Elizabeth V.; Kentsis, Alex; Rodriguez-Galindo, Carlos; Mukai, Shizuo; Shaw, Bryan F.

2013-01-01

Retinoblastoma is the most common primary intraocular tumor in children. The first sign that is often reported by parents is the appearance of recurrent leukocoria (i.e., “white eye”) in recreational photographs. A quantitative definition or scale of leukocoria – as it appears during recreational photography – has not been established, and the amount of clinical information contained in a leukocoric image (collected by a parent) remains unknown. Moreover, the hypothesis that photographic leukocoria can be a sign of early stage retinoblastoma has not been tested for even a single patient. This study used commercially available software (Adobe Photoshop®) and standard color space conversion algorithms (operable in Microsoft Excel®) to quantify leukocoria in actual “baby pictures” of 9 children with retinoblastoma (that were collected by parents during recreational activities i.e., in nonclinical settings). One particular patient with bilateral retinoblastoma (“Patient Zero”) was photographed >7, 000 times by his parents (who are authors of this study) over three years: from birth, through diagnosis, treatment, and remission. This large set of photographs allowed us to determine the longitudinal and lateral frequency of leukocoria throughout the patient's life. This study establishes: (i) that leukocoria can emerge at a low frequency in early-stage retinoblastoma and increase in frequency during disease progression, but decrease upon disease regression, (ii) that Hue, Saturation and Value (i.e., HSV color space) are suitable metrics for quantifying the intensity of retinoblastoma-linked leukocoria; (iii) that different sets of intraocular retinoblastoma tumors can produce distinct leukocoric reflections; and (iv) the Saturation-Value plane of HSV color space represents a convenient scale for quantifying and classifying pupillary reflections as they appear during recreational photography. PMID:24204654

Birth order, family environments, academic and affective outcomes.

PubMed

Marjoribanks, Kevin

2003-06-01

Relations were examined among birth order, family social status, family learning environments, and a set of affective and academic outcomes. Data were collected as part of an Australian longitudinal study (4,171 females and 3,718 males). Analysis suggested that birth order continued to have small but significant associations with adolescents' self-concept and educational aspirations and with young adults' educational attainment, after taking into account differences in family social status and family learning environments.

Polylingual Development among Turkish Speakers in a Danish Primary School--A Critical View on the Fourth Grade Slump

ERIC Educational Resources Information Center

Møller, Janus Spindler; Jørgensen, J. Normann; Holmen, Anne

2014-01-01

In this paper we report on a longitudinal study of the linguistic development among Turkish-speaking children in Denmark. A series of data were collected from a group of children attending a public school in Køge during the period 1989-1998 and from the same group--now in their 20s--in 2006-2007. The data set has been analyzed from a number of…

Longitudinal Associations Between Relationship Quality and Coparenting Across the Transition to Parenthood: A Dyadic Perspective

PubMed Central

Le, Yunying; McDaniel, Brandon T.; Leavitt, Chelom E.; Feinberg, Mark E.

2016-01-01

The couple and coparenting relationship are theorized to influence one another in a reciprocal manner over time. Empirical evidence demonstrates cross-sectional associations between the two as well as prospective predictions of coparenting by relationship quality and vice versa. However, less is known about the longitudinal reciprocity between the couple relationship and coparenting from the perspective of both parents. The current study sought to examine longitudinal associations between relationship quality and coparenting support/undermining across the transition to parenthood from a dyadic perspective. Participants were 164 cohabitating heterosexual couples expecting their first child assessed during pregnancy and at 6 and 36 months after birth. Actor Partner Interdependence Modeling (APIM) was used to examine, for both men and women, (1) stability over time in relationship quality and coparenting; (2) reciprocal associations between relationship quality and coparenting support/undermining; as well as (3) the gender differences in those associations. Moderate rank-order stability in relationship quality and coparenting support/undermining across the first three years of parenthood was demonstrated. For women, but not men, findings suggested longitudinal reciprocal associations between relationship quality and coparenting support/undermining. Specifically, our findings suggested that prenatal relationship quality sets the stage for coparenting functioning after birth for both men and women but that coparenting functioning is then connected to subsequent feelings about the romantic relationship only for women. PMID:27183188

Use of administrative records to describe longitudinal patterns of health services use among veterans.

PubMed Central

Williams, B C; Mehr, D R; Fries, B E

1994-01-01

Administrative records of the Department of Veterans Affairs (DVA) and the National Death Index were linked to create a four-year longitudinal database that describes the clinical status, hospital and nursing home use, and mortality for a nationwide cohort of persons admitted to DVA nursing homes (n = 23,039). Using Social Security Numbers as identifiers, the records of only 6% of these persons had logically inconsistent or implausible patterns. Nineteen percent of the remaining records had correctable logical errors. Information on the creation, consistency, and potential uses of this database may prove useful to health services researchers interested in describing longitudinal patterns of health care use across multiple settings within and outside the DVA. PMID:7719818

Registration Methods for IVUS: Transversal and Longitudinal Transducer Motion Compensation.

PubMed

Talou, Gonzalo D Maso; Blanco, Pablo J; Larrabide, Ignacio; Bezerra, Cristiano Guedes; Lemos, Pedro A; Feijoo, Raul A

2017-04-01

Intravascular ultrasound (IVUS) is a fundamental imaging technique for atherosclerotic plaque assessment, interventionist guidance, and, ultimately, as a tissue characterization tool. The studies acquired by this technique present the spatial description of the vessel during the cardiac cycle. However, the study frames are not properly sorted. As gating methods deal with the cardiac phase classification of the frames, the gated studies lack motion compensation between vessel and catheter. In this study, we develop registration strategies to arrange the vessel data into its rightful spatial sequence. Registration is performed by compensating longitudinal and transversal relative motion between vessel and catheter. Transversal motion is identified through maximum likelihood estimator optimization, while longitudinal motion is estimated by a neighborhood similarity estimator among the study frames. A strongly coupled implementation is proposed to compensate for both motion components at once. Loosely coupled implementations (DLT and DTL) decouple the registration process, resulting in more computationally efficient algorithms in detriment of the size of the set of candidate solutions. The DTL outperforms DLT and coupled implementations in terms of accuracy by a factor of 1.9 and 1.4, respectively. Sensitivity analysis shows that perivascular tissue must be considered to obtain the best registration outcome. Evidences suggest that the method is able to measure axial strain along the vessel wall. The proposed registration sorts the IVUS frames for spatial location, which is crucial for a correct interpretation of the vessel wall kinematics along the cardiac phases.

Determinants and impact of suboptimal asthma control in Europe: The INTERNATIONAL CROSS-SECTIONAL AND LONGITUDINAL ASSESSMENT ON ASTHMA CONTROL (LIAISON) study.

PubMed

Braido, Fulvio; Brusselle, Guy; Guastalla, Daniele; Ingrassia, Eleonora; Nicolini, Gabriele; Price, David; Roche, Nicolas; Soriano, Joan B; Worth, Heinrich

2016-05-14

According to the Global Initiative of Asthma, the aim of asthma treatment is to gain and maintain control. In the INTERNATIONAL CROSS-SECTIONAL AND LONGITUDINAL ASSESSMENT ON ASTHMA CONTROL (LIAISON) study, we evaluated the level of asthma control and quality of life (QoL), as well as their determinants and impact in a population consulting specialist settings. LIAISON is a prospective, multicentre, observational study with a cross-sectional and a 12-month longitudinal phase. Adults with an asthma diagnosis since at least 6 months, receiving the same asthma treatment in the 4 weeks before enrolment were included. Asthma control was assessed with the 6-item Asthma Control Questionnaire (ACQ) and QoL with the MiniAsthma Quality of Life Questionnaire (MiniAQLQ). Overall, 8111 asthmatic patients were enrolled in 12 European countries. Asthma control was suboptimal in 56.5 % of patients and it was associated with poorer asthma-related QoL, higher risk of exacerbations and greater consumption of healthcare resources. Variables associated with suboptimal control were age, gender, obesity, smoking and comorbidities. Major determinants of poor asthma control were seasonal worsening and persisting exposure to allergens/irritants/triggers, followed by treatment-related issues. The cross-sectional phase results confirm that suboptimal control is frequent and has a high individual and economic impact. The clinicaltrials.gov identifier is NCT01567280 .

Growth trajectories in the children of mothers with eating disorders: a longitudinal study

PubMed Central

Easter, Abigail; Howe, Laura D; Tilling, Kate; Schmidt, Ulrike; Treasure, Janet; Micali, Nadia

2014-01-01

Objective The aim of this study was to examine longitudinal patterns of growth trajectories in children of women with eating disorders (ED): anorexia nervosa (AN) and bulimia nervosa (BN). Design Prospective longitudinal birth cohort; Avon Longitudinal Study of Parents and Children (ALSPAC). Setting South West England, UK. Participants The sample consisted of women and their children (n=10 190) from ALSPAC. Patterns of growth among children of women reporting a history of AN (n=137), BN (n=165), both AN and BN (n=68) and other psychiatric disorders (n=920) were compared with an unexposed group of children (n=8900). Main outcome measures Height and weight data, from birth to 10 years, were extracted from health visitor records, parental report from questionnaires and clinic attendances. Growth trajectories were analysed using mixed-effects models and constructed separately for male and female children. Results Between birth and 10 years, male children of women with BN were taller than children in the unexposed group. Male children of women with a history of AN and BN, and female children of women with AN, were shorter throughout childhood. Between the ages of 2 and 5, higher body mass index (BMI) was observed in male children in all maternal ED groups. Conversely, female children of women with AN had a BMI of −0.35 kg/m2 lower at 2 years compared with the unexposed group, with catch-up by age 10. Conclusions Early childhood growth has been found to predict weight gain in adolescence and adulthood, and may be a risk factor for the development of an ED. These findings therefore have public health implications in relation to the prevention of weight-related and eating-related disorders later in life. PMID:24674996

Automatic detection of new tumors and tumor burden evaluation in longitudinal liver CT scan studies.

PubMed

Vivanti, R; Szeskin, A; Lev-Cohain, N; Sosna, J; Joskowicz, L

2017-11-01

Radiological longitudinal follow-up of liver tumors in CT scans is the standard of care for disease progression assessment and for liver tumor therapy. Finding new tumors in the follow-up scan is essential to determine malignancy, to evaluate the total tumor burden, and to determine treatment efficacy. Since new tumors are typically small, they may be missed by examining radiologists. We describe a new method for the automatic detection and segmentation of new tumors in longitudinal liver CT studies and for liver tumors burden quantification. Its inputs are the baseline and follow-up CT scans, the baseline tumors delineation, and a tumor appearance prior model. Its outputs are the new tumors segmentations in the follow-up scan, the tumor burden quantification in both scans, and the tumor burden change. Our method is the first comprehensive method that is explicitly designed to find new liver tumors. It integrates information from the scans, the baseline known tumors delineations, and a tumor appearance prior model in the form of a global convolutional neural network classifier. Unlike other deep learning-based methods, it does not require large tagged training sets. Our experimental results on 246 tumors, of which 97 were new tumors, from 37 longitudinal liver CT studies with radiologist approved ground-truth segmentations, yields a true positive new tumors detection rate of 86 versus 72% with stand-alone detection, and a tumor burden volume overlap error of 16%. New tumors detection and tumor burden volumetry are important for diagnosis and treatment. Our new method enables a simplified radiologist-friendly workflow that is potentially more accurate and reliable than the existing one by automatically and accurately following known tumors and detecting new tumors in the follow-up scan.

Longitudinal assessment of associations between food insecurity, antiretroviral adherence and HIV treatment outcomes in rural Uganda.

PubMed

Weiser, Sheri D; Palar, Kartika; Frongillo, Edward A; Tsai, Alexander C; Kumbakumba, Elias; Depee, Saskia; Hunt, Peter W; Ragland, Kathleen; Martin, Jeffrey; Bangsberg, David R

2014-01-02

Food insecurity is a potentially important barrier to the success of antiretroviral therapy (ART) programs in resource-limited settings. We undertook a longitudinal study in rural Uganda to estimate the associations between food insecurity and HIV treatment outcomes. Longitudinal cohort study. Participants were from the Uganda AIDS Rural Treatment Outcomes study and were followed quarterly for blood draws and structured interviews. We measured food insecurity with the validated Household Food Insecurity Access Scale. Our primary outcomes were: ART nonadherence (adherence <90%) measured by visual analog scale; incomplete viral load suppression (>400 copies/ml); and low CD4 T-cell count (<350 cells/μl). We used generalized estimating equations to estimate the associations, adjusting for socio-demographic and clinical variables. We followed 438 participants for a median of 33 months; 78.5% were food insecure at baseline. In adjusted analyses, food insecurity was associated with higher odds of ART nonadherence [adjusted odds ratio (AOR) 1.56, 95% confidence interval (CI) 1.10-2.20, P < 0.05], incomplete viral suppression (AOR 1.52, 95% CI 1.18-1.96, P < 0.01), and CD4 T-cell count less than 350 (AOR 1.47, 95% CI 1.24-1.74, P < 0.01). Adding adherence as a covariate to the latter two models removed the association between food insecurity and viral suppression, but not between food insecurity and CD4 T-cell count. Food insecurity is longitudinally associated with poor HIV outcomes in rural Uganda. Intervention research is needed to determine the extent to which improved food security is causally related to improved HIV outcomes and to identify the most effective policies and programs to improve food security and health.

Biases in Multicenter Longitudinal PET Standardized Uptake Value Measurements1

PubMed Central

Doot, Robert K; Pierce, Larry A; Byrd, Darrin; Elston, Brian; Allberg, Keith C; Kinahan, Paul E

2014-01-01

This study investigates measurement biases in longitudinal positron-emission tomography/computed tomography (PET/CT) studies that are due to instrumentation variability including human error. Improved estimation of variability between patient scans is of particular importance for assessing response to therapy and multicenter trials. We used National Institute of Standards and Technology-traceable calibration methodology for solid germanium-68/gallium-68 (68Ge/68Ga) sources used as surrogates for fluorine-18 (18F) in radionuclide activity calibrators. One cross-calibration kit was constructed for both dose calibrators and PET scanners using the same 9-month half-life batch of 68Ge/68Ga in epoxy. Repeat measurements occurred in a local network of PET imaging sites to assess standardized uptake value (SUV) errors over time for six dose calibrators from two major manufacturers and for six PET/CT scanners from three major manufacturers. Bias in activity measures by dose calibrators ranged from -50% to 9% and was relatively stable over time except at one site that modified settings between measurements. Bias in activity concentration measures by PET scanners ranged from -27% to 13% with a median of 174 days between the six repeat scans (range, 29 to 226 days). Corresponding errors in SUV measurements ranged from -20% to 47%. SUV biases were not stable over time with longitudinal differences for individual scanners ranging from -11% to 59%. Bias in SUV measurements varied over time and between scanner sites. These results suggest that attention should be paid to PET scanner calibration for longitudinal studies and use of dose calibrator and scanner cross-calibration kits could be helpful for quality assurance and control. PMID:24772207

Climate-driven longitudinal trends in pasture-borne helminth infections of dairy cattle.

PubMed

Charlier, Johannes; Ghebretinsae, Aklilu H; Levecke, Bruno; Ducheyne, Els; Claerebout, Edwin; Vercruysse, Jozef

2016-12-01

Helminth parasites of grazing ruminants are highly prevalent globally and impact negatively on animal productivity and food security. There is a growing concern that climate change increases helminth disease frequency and intensity. In Europe, these concerns stem from case reports and theoretical life cycle models assessing the effects of climate change scenarios on helminth epidemiology. We believe this study is the first to investigate climate-driven trends in helminth infections of cattle on a cohort of randomly selected farms. One thousand, six hundred and eighty dairy farms were monitored over an 8year period for the two major helminth infections in temperate climate regions and climate-driven trends were investigated by multivariable linear mixed models. The general levels of exposure to Fasciola hepatica decreased over the study period while those to Ostertagia ostertagi increased, and this could at least be partially explained by meteorological factors (i.e. the number of rainy (precipitation >1mm) and warm days (average daily temperature >10°C) in a year). The longitudinal trends varied according to the altitude and the agricultural region of the farm. This study shows that longitudinal epidemiological data from sentinel farms combined with meteorological datasets can significantly contribute to understanding the effects of climate on infectious disease dynamics. When local environmental conditions are taken into account, the effects of climate change on disease dynamics can also be understood at more local scales. We recommend setting up a longitudinal sampling strategy across Europe in order to monitor climate-driven changes in helminth disease risk to inform adaptation strategies to promote animal health and productivity. Copyright © 2016 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

A longitudinal test of the predictions of the interpersonal-psychological theory of suicidal behaviour for passive and active suicidal ideation in a large community-based cohort.

PubMed

Batterham, Philip J; Walker, Jennie; Leach, Liana S; Ma, Jennifer; Calear, Alison L; Christensen, Helen

2018-02-01

The Interpersonal-Psychological Theory of Suicide (IPTS) aims to elucidate the key antecedents of suicide deaths. Limited research has tested the IPTS in a community setting, and very little longitudinal research has been conducted. The current study longitudinally tested the predictions of the IPTS for suicidal ideation in a large population-based sample. The PATH through Life study assesses three age cohorts (20's, 40's, 60's) every four years. Two interpersonal factors were estimated at the third wave of assessment: thwarted belongingness (TB) and perceived burdensomeness (PB). The roles of these factors in suicide ideation (active and passive) four years later were estimated using logistic regression models (n = 4545). A one SD increase in TB was associated with increased odds of 37% for passive ideation and 24% for active ideation. For PB, odds were increased 2.5-fold for passive ideation and 2.4-fold for active ideation. A significant negative PB × TB interaction was found for passive but not active ideation. Effects were not consistent by age group or gender. Proxy measures were used to assess the constructs. The extended timeframe and low prevalence of suicidal ideation limited power to find effects within subgroups. Although TB and PB were individually associated with suicidal thoughts, little evidence was found for the key predictions of the IPTS longitudinally. Further investigation of the dynamic interplay between interpersonal factors over time is needed. Copyright © 2017 Elsevier B.V. All rights reserved.

Approaches to maximising the accuracy of anthropometric data on children: review and empirical evaluation using the Australian Longitudinal Study of Indigenous Children.

PubMed

Thurber, Katherine A; Banks, Emily; Banwell, Cathy

2014-11-28

Despite the burgeoning research interest in weight status, in parallel with the increase in obesity worldwide, research describing methods to optimise the validity and accuracy of measured anthropometric data is lacking. Even when 'gold standard' methods are employed, no data are 100% accurate, yet the accuracy of anthropometric data is critical to produce robust and interpretable findings. To date, described methods for identifying data that are likely to be inaccurate seem to be ad hoc or lacking in clear justification. This paper reviews approaches to evaluating the accuracy of cross-sectional and longitudinal data on height and weight in children, focusing on recommendations from the World Health Organization (WHO). This review, together with expert consultation, informed the development of a method for processing and verifying longitudinal anthropometric measurements of children. This approach was then applied to data from the Australian Longitudinal Study of Indigenous Children. The review identified the need to assess the likely plausibility of data by (a) examining deviation from the WHO reference population by calculating age- and sex-adjusted height, weight and body mass index z-scores, and (b) examining changes in height and weight in individuals over time. The method developed identified extreme measurements and implausible intraindividual trajectories. It provides evidence-based criteria for the exclusion of data points that are most likely to be affected by measurement error. This paper presents a probabilistic approach to identifying anthropometric measurements that are likely to be implausible. This systematic, practical method is intended to be reproducible in other settings, including for validating large databases.

Interaction of the TaqIA polymorphism and poor parental socialization on changes in adolescent marijuana use.

PubMed

Vaske, Jamie

2013-02-01

The current study uses data from the genetic subsample from the National Longitudinal Study of Adolescent Health (Add Health) in waves I and II (ages of 11-19 and 12-20 respectively) to investigate the interaction of the TaqIA polymorphism and poor parental socialization on changes in adolescent marijuana use. Results reveal that TaqIA interacts with poor parental rule setting, but not quality of mother-child communication, to influence changes in marijuana use. Adolescents who are homozygous for the A1 and whose parents allow the youth to set their own curfew experience significant increases in marijuana use during adolescence. In contrast, youths with the A1/A1 genotype whose parents do not allow the adolescent to set their own curfew experience significant decreases in the frequency of marijuana use. These results suggest that direct parental social control may effectively suppress the genetic risk of the A1/A1 genotype on marijuana use in adolescence. The study's limitations are noted.

Family structure and child food insecurity.

PubMed

Miller, Daniel P; Nepomnyaschy, Lenna; Ibarra, Gabriel Lara; Garasky, Steven

2014-07-01

We examined whether food insecurity was different for children in cohabiting or repartnered families versus those in single-mother or married-parent (biological) families. We compared probabilities of child food insecurity (CFI) across different family structures in 4 national data sets: the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B), the Fragile Families and Child Wellbeing Study (FFCWS), the Early Childhood Longitudinal Study-Kindergarten Cohort (ECLS-K), and the Panel Study of Income Dynamics-Child Development Supplement (PSID-CDS). Unadjusted probabilities of CFI in cohabiting or repartnered families were generally higher than in married-biological-parent families and often statistically indistinguishable from those of single-mother families. However, after adjustment for sociodemographic factors, most differences between family types were attenuated and most were no longer statistically significant. Although children whose biological parents are cohabiting or whose biological mothers have repartnered have risks for food insecurity comparable to those in single-mother families, the probability of CFI does not differ by family structure when household income, family size, and maternal race, ethnicity, education, and age were held at mean levels.

From Communication Skills to Skillful Communication: A Longitudinal Integrated Curriculum for Critical Care Medicine Fellows.

PubMed

Roze des Ordons, Amanda L; Doig, Christopher J; Couillard, Philippe; Lord, Jason

2017-04-01

Communication with patients and families in critical care medicine (CCM) can be complex and challenging. A longitudinal curricular model integrating multiple techniques within classroom and clinical milieus may facilitate skillful communication across diverse settings. In 2014-2015, the authors developed and implemented a curriculum for CCM fellows at the Cumming School of Medicine, University of Calgary, to promote the longitudinal development of skillful communication. A departmental needs assessment informed curriculum development. Five 4-hour classroom sessions were developed: basic communication principles, family meetings about goals and transitions of care, discussing patient safety incidents, addressing conflict, and offering organ donation. Teaching methods-including instructor-led presentations incorporating a consistent framework for approaching challenging conversations, simulation and clinical practice, and feedback from peers, trained facilitators, family members, and clinicians-supported integration of skills into the clinical setting and longitudinal development of skillful communication. Seven fellows participated during the first year of the curriculum. CCM fellows engaged enthusiastically in the program, commented that the framework provided was helpful, and highly valued the opportunity to practice challenging communication scenarios, learn from observing their peers, and receive immediate feedback. More detailed accounts of fellows', patients', and family members' experiences will be obtained to guide curricular development. The curriculum will be expanded to involve other members of the multidisciplinary intensive care unit team, and faculty education initiatives will be offered to enhance the quality of the feedback provided. The impact of the curriculum on initial skill development, retention, and progression will be assessed.

Setting times for endodontic sealers under clinical usage and in vitro conditions.

PubMed

Allan, N A; Walton, R C; Schaeffer, M A; Schaffer, A

2001-06-01

The object of this study was to determine the set of sealers under simulated clinical versus bench-top conditions. One hundred twenty extracted teeth were divided into four groups (Roth's, Tubuliseal, Sealapex, AH26). Canal preparation and lateral condensation were performed with the four sealers (30 teeth each). Teeth were placed into 100% humidity at 37 degrees C. The same mix of sealer on a glass slab was stored within the same environment. After 1 to 8 wk the teeth were fractured longitudinally to expose the gutta-percha-sealer interface. Evaluation, both clinical and in vitro, was qualitative under a microscope with a needle tip. The degree of set was categorized as: (a) unset (smearable), (b) partially set (indented easily, but not smearable), or (3) set (not easily indentable). There were inconsistencies in setting times within and between groups. In canals most of three (AH26, Sealapex, and Tubuliseal) were partially set after 1 wk; set was complete after 4 wk. Roth's was very slow; most were unset after 8 wk. Sealers on the glass slab set much more rapidly. In conclusion, under clinical conditions, sealers set slowly (particularly Roth's) and were more delayed than when tested in vitro.

Annotating longitudinal clinical narratives for de-identification: The 2014 i2b2/UTHealth corpus.

PubMed

Stubbs, Amber; Uzuner, Özlem

2015-12-01

The 2014 i2b2/UTHealth natural language processing shared task featured a track focused on the de-identification of longitudinal medical records. For this track, we de-identified a set of 1304 longitudinal medical records describing 296 patients. This corpus was de-identified under a broad interpretation of the HIPAA guidelines using double-annotation followed by arbitration, rounds of sanity checking, and proof reading. The average token-based F1 measure for the annotators compared to the gold standard was 0.927. The resulting annotations were used both to de-identify the data and to set the gold standard for the de-identification track of the 2014 i2b2/UTHealth shared task. All annotated private health information were replaced with realistic surrogates automatically and then read over and corrected manually. The resulting corpus is the first of its kind made available for de-identification research. This corpus was first used for the 2014 i2b2/UTHealth shared task, during which the systems achieved a mean F-measure of 0.872 and a maximum F-measure of 0.964 using entity-based micro-averaged evaluations. Copyright © 2015 Elsevier Inc. All rights reserved.

Optimization of Sample Preparation and Instrumental Parameters for the Rapid Analysis of Drugs of Abuse in Hair samples by MALDI-MS/MS Imaging

NASA Astrophysics Data System (ADS)

Flinders, Bryn; Beasley, Emma; Verlaan, Ricky M.; Cuypers, Eva; Francese, Simona; Bassindale, Tom; Clench, Malcolm R.; Heeren, Ron M. A.

2017-08-01

Matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) has been employed to rapidly screen longitudinally sectioned drug user hair samples for cocaine and its metabolites using continuous raster imaging. Optimization of the spatial resolution and raster speed were performed on intact cocaine contaminated hair samples. The optimized settings (100 × 150 μm at 0.24 mm/s) were subsequently used to examine longitudinally sectioned drug user hair samples. The MALDI-MS/MS images showed the distribution of the most abundant cocaine product ion at m/z 182. Using the optimized settings, multiple hair samples obtained from two users were analyzed in approximately 3 h: six times faster than the standard spot-to-spot acquisition method. Quantitation was achieved using longitudinally sectioned control hair samples sprayed with a cocaine dilution series. A multiple reaction monitoring (MRM) experiment was also performed using the `dynamic pixel' imaging method to screen for cocaine and a range of its metabolites, in order to differentiate between contaminated hairs and drug users. Cocaine, benzoylecgonine, and cocaethylene were detectable, in agreement with analyses carried out using the standard LC-MS/MS method. [Figure not available: see fulltext.

Long-term efficacy of first line antiretroviral therapy in Indian HIV-1 infected patients: a longitudinal cohort study.

PubMed

Neogi, Ujjwal; Heylen, Elsa; Shet, Anita; Chandy, Sara; Shamsunder, Ranjani; Sönnerborg, Anders; Ekstrand, Maria L

2013-01-01

Short term efficacy of combination antiretroviral therapy (cART) in resource-constrained settings is comparable to that found in western studies. However, long term data are limited. India has the third largest HIV infected population in the world but the long-term outcome of first line therapy according to the national guidelines has not been evaluated yet. Therefore, we conducted a long-term longitudinal analysis of the efficacy of the national first-line therapy in India from an observational cohort of Indian patients in two different clinical settings. A total 323 patients who had been on ART for a median of 23 months and achieved virological suppression <100 copies/ml by their study baseline visit, were included and followed for two years. Blood samples were collected every six months for viral load and CD4 count. Drug resistance genotyping was performed when the viral load was >2000 copies/mL. Adherence and treatment interruptions (>48 h) were assessed via self-report. In the studied patients, the median duration of viral suppression was 44 months; 15.8% of patients showed viral rebound, and 2.8% viral failure. Viral rebound or failure was significantly negatively related to perfect adherence (100% adherence and no treatment interruption >48 hrs). Virological re-suppression in the subsequent visit was observed in three patients without any change in therapy despite the presence of key mutations. Our study reports for the first time, a good long-term response to the first line therapy for a median of nearly four years although a less than perfect adherence increases the risk for treatment failure and subsequent drug resistance development. The empirical findings in this study also indicate the overall success of the Indian ART program in two different settings which likely are representative of other clinics that operate under the national guidelines.

The education of scientists: Gender differences during the early life course

NASA Astrophysics Data System (ADS)

Shauman, Kimberlee Akin

In this dissertation, I examine gender differences in the science and engineering (S/E) educational trajectory--the pre-college and college experiences that lead to specialized education and qualification for an S/E occupation. This research makes important contributions by providing detailed and updated information about gender differences in the timing and causal mechanisms for flows into and out of the S/E educational trajectory. By using longitudinal data to model the linkages between past and future science experiences, I measure the dynamic process underlying the S/E educational trajectory and challenge the predominant "science pipeline" conceptualization of this process. I use the life course perspective as a guide to conceptualizing the S/E trajectory and to analyzing the social forces that shape the educational and career goals of individual women and men. I develop a conceptual model that specifies how the effects of a set of social influences gradually shift in measurable and predictable ways over the educational "life histories" of individuals. The causal factors in the model are (1) individual influences such as ability and attitudes, (2) familial influences, and (3) the influence of significant others in the social structure. To uncover gender differences in the process of becoming a scientist, I use four nationally representative longitudinal studies: the National Education Longitudinal Study of 1988, the Longitudinal Study of American Youth, the High School and Beyond, and the National Longitudinal Study of the Class of 1972. The empirical analyses of this dissertation focus on the individual and familial influences on participation in the S/E educational trajectory. Past experience in S/E education increases the likelihood of future participation, but persistence in the S/E trajectory is not the only viable route to S/E degree attainment. Entry into S/E majors during college is common, and it is a prevalent path to an S/E bachelor's degree, especially for women. The transition from high school to college is the point where the educational paths of males and females diverge significantly. Expectations about future family roles have the greatest influence on the gender differences in the patterns of participation in the S/E educational trajectory.

Longitudinal spillover effects of conflict resolution styles between adolescent-parent relationships and adolescent friendships.

PubMed

Van Doorn, Muriel D; Branje, Susan J T; Vandervalk, Inge E; De Goede, Irene H A; Meeus, Wim H J

2011-02-01

This study longitudinally investigated spillover effects of conflict resolution styles in adolescent-parent relationships and adolescent friendships. Questionnaires about conflict resolution styles with parents and best friends were completed by adolescents from two age cohorts: 559 early adolescents (mean age 13.4) and 327 middle adolescents (mean age 17.7). Path analyses on two waves, with a three-year interval, indicated that in the early-to-middle adolescent group positive problem solving and conflict engagement spilled over from adolescent-parent relationships to adolescent friendships and not from adolescent friendships to adolescent-parent relationships. In the middle-to-late adolescent group, we found bidirectional spillover effects for these two conflict resolution styles. For withdrawal, we found bidirectional spillover effects in both cohorts. This study showed that both parents and friends set the stage for exercising and learning conflict resolution styles and thereby shape adolescents' future conflict behavior. PsycINFO Database Record (c) 2011 APA, all rights reserved.

Computerized Self-Administered Measures of Mood and Appetite for Older Adults: The Novel Assessment of Nutrition and Ageing Toolkit.

PubMed

Brown, Laura J E; Adlam, Tim; Hwang, Faustina; Khadra, Hassan; Maclean, Linda M; Rudd, Bridey; Smith, Tom; Timon, Claire; Williams, Elizabeth A; Astell, Arlene J

2018-02-01

The "Novel Assessment of Nutrition and Ageing" (NANA) toolkit is a computerized system for collecting longitudinal information about older adults' health and behavior. Here, we describe the validation of six items for measuring older adults' self-reported mood and appetite as part of the NANA system. In Study 1, 48 community-living older adults (aged 65-89 years) completed NANA measures of their current mood and appetite alongside standard paper measures, on three occasions, in a laboratory setting. In Study 2, 40 community-living older adults (aged 64-88 years) completed daily NANA measures of momentary mood and appetite in their own homes, unsupervised, alongside additional measures of health and behavior, over three 7-day periods. The NANA measures were significantly correlated with standard measures of mood and appetite, and showed stability over time. They show utility for tracking mood and appetite longitudinally, and for better understanding links with other aspects of health and behavior.

Recent and Past Intimate Partner Abuse and HIV Risk Among Young Women

PubMed Central

Teitelman, Anne M.; Ratcliffe, Sarah J.; Dichter, Melissa E.; Sullivan, Cris M.

2011-01-01

Objective To examine the associations between past intimate partner abuse experienced during adolescence (verbal and physical), recent intimate partner abuse (verbal, physical, and sexual), and HIV risk (as indicated by lack of condom use) for sexually active young adult women in relationships with male partners. Design Secondary data analysis of waves II and III of the National Longitudinal Study of Adolescent Health (Add Health). Setting The Add Health Study is a longitudinal, in-home survey of a nationally representative sample of adolescents. Sample Analyses involved 2,058 sexually active young adult women. Main Outcome Measures HIV risk was measured by consistent condom use over the past 12 months. Results Physical and verbal abuse experienced in adolescence were associated with physical/verbal abuse experienced in young adulthood. Young, sexually active women experiencing no abuse in their relationships were more likely to consistently use condoms in the past 12 months than were their abused counterparts. Conclusion A causal pathway may exist between prior abuse, current abuse, and HIV risk. PMID:18336447

Video Gaming Disorder and Sport and Exercise in Emerging Adulthood: A Longitudinal Study.

PubMed

Henchoz, Yves; Studer, Joseph; Deline, Stéphane; N'Goran, Alexandra A; Baggio, Stéphanie; Gmel, Gerhard

2016-01-01

Among the negative consequences of video gaming disorder, decreased participation in sport and exercise has received little attention. This study aimed to assess the longitudinal association between video gaming disorder and the level of sport and exercise in emerging adult men. A questionnaire was completed at baseline and 15-month follow-up by a representative national sample of 4,933 respondents. The seven items of the Game Addiction Scale were used to construct a latent variable representing video gaming disorder. Level of sport and exercise was also self-reported. Cross-lagged path modeling indicated a reciprocal causality between video gaming disorder and the level of sport and exercise, even after adjusting for a large set of confounders. These findings support the need for better promotion of sport and exercise among emerging adults in order to contribute to the prevention of video gaming disorder, and to raise the level of sport and exercise activity in addicted gamers.

Covariance Partition Priors: A Bayesian Approach to Simultaneous Covariance Estimation for Longitudinal Data.

PubMed

Gaskins, J T; Daniels, M J

2016-01-02

The estimation of the covariance matrix is a key concern in the analysis of longitudinal data. When data consists of multiple groups, it is often assumed the covariance matrices are either equal across groups or are completely distinct. We seek methodology to allow borrowing of strength across potentially similar groups to improve estimation. To that end, we introduce a covariance partition prior which proposes a partition of the groups at each measurement time. Groups in the same set of the partition share dependence parameters for the distribution of the current measurement given the preceding ones, and the sequence of partitions is modeled as a Markov chain to encourage similar structure at nearby measurement times. This approach additionally encourages a lower-dimensional structure of the covariance matrices by shrinking the parameters of the Cholesky decomposition toward zero. We demonstrate the performance of our model through two simulation studies and the analysis of data from a depression study. This article includes Supplementary Material available online.