Determinants of new-onset diabetes in older adults—Results of a national cohort study.

PubMed

Tsai, Alan C; Lee, Shu-Hui

2015-10-01

Diabetes mellitus is prevalent in many countries around the world, but the potential causal factors are not clearly known. We attempted to determine the risk factors for new-onset diabetes in ≥53-year old Taiwanese. We analyzed the 1999 and 2003 datasets of the Taiwan Longitudinal Survey on Aging (TLSA). We performed logistic regression analyses to determine the cross-sectional and longitudinal (1999-2003) associations of the sociodemographic, lifestyle, and health-related variables with diabetes and new-onset diabetes, respectively. We excluded those who were diabetic at baseline in the longitudinal analysis. Results of the cross-sectional analysis showed that higher weight, past betel-quid chewing, IADL dependency, hypertension, heart disease, chronic kidney disease and depressive symptoms were positively associated with diabetes while alcohol drinking was negatively associated with diabetes. Longitudinal analysis showed that excessive weight, physical inactivity, depressive symptoms, and hypertension were associated with increased likelihood of new-onset diabetes while higher physical activity was associated with reduced likelihood of new-onset diabetes. Cigarette-smoking and moderate alcohol drinking showed no clear impacts on new-onset diabetes in older Taiwanese. Results show that excessive weight, physical inactivity, hypertension and depressive symptoms are the major risk factors for new-onset diabetes for both Eastern and Western populations, whereas smoking and alcohol drinking have varying impacts among these populations. Better understanding of these relationships should be helpful for planning effective health promotion strategies for reducing the risk of new-onset diabetes in older adults. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Using Administrative Data for Longitudinal Substance Abuse Research

PubMed Central

Evans, Elizabeth; Grella, Christine E.; Murphy, Debra A.; Hser, Yih-Ing

2008-01-01

The utilization of administrative data in substance abuse research has become more widespread than ever. This selective review synthesizes recent extant research from 31 articles to consider what has been learned from using administrative data to conduct longitudinal substance abuse research in four overlapping areas: (1) service access and utilization, (2) underrepresented populations, (3) treatment outcomes, and (4) cost analysis. Despite several notable limitations, administrative data contribute valuable information, particularly in the investigation of service system interactions and outcomes among substance abusers as they unfold and influence each other over the long term. This critical assessment of the advantages and disadvantages of using existing administrative data within a longitudinal framework should stimulate innovative thinking regarding future applications of administrative data for longitudinal substance abuse research purposes. PMID:18679805

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…

Detection of a novel, integrative aging process suggests complex physiological integration.

PubMed

Cohen, Alan A; Milot, Emmanuel; Li, Qing; Bergeron, Patrick; Poirier, Roxane; Dusseault-Bélanger, Francis; Fülöp, Tamàs; Leroux, Maxime; Legault, Véronique; Metter, E Jeffrey; Fried, Linda P; Ferrucci, Luigi

2015-01-01

Many studies of aging examine biomarkers one at a time, but complex systems theory and network theory suggest that interpretations of individual markers may be context-dependent. Here, we attempted to detect underlying processes governing the levels of many biomarkers simultaneously by applying principal components analysis to 43 common clinical biomarkers measured longitudinally in 3694 humans from three longitudinal cohort studies on two continents (Women's Health and Aging I & II, InCHIANTI, and the Baltimore Longitudinal Study on Aging). The first axis was associated with anemia, inflammation, and low levels of calcium and albumin. The axis structure was precisely reproduced in all three populations and in all demographic sub-populations (by sex, race, etc.); we call the process represented by the axis "integrated albunemia." Integrated albunemia increases and accelerates with age in all populations, and predicts mortality and frailty--but not chronic disease--even after controlling for age. This suggests a role in the aging process, though causality is not yet clear. Integrated albunemia behaves more stably across populations than its component biomarkers, and thus appears to represent a higher-order physiological process emerging from the structure of underlying regulatory networks. If this is correct, detection of this process has substantial implications for physiological organization more generally.

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

Two Populations of Sunspots: Differential Rotation

NASA Astrophysics Data System (ADS)

Nagovitsyn, Yu. A.; Pevtsov, A. A.; Osipova, A. A.

2018-03-01

To investigate the differential rotation of sunspot groups using the Greenwich data, we propose an approach based on a statistical analysis of the histograms of particular longitudinal velocities in different latitude intervals. The general statistical velocity distributions for all such intervals are shown to be described by two rather than one normal distribution, so that two fundamental rotation modes exist simultaneously: fast and slow. The differentiality of rotation for the modes is the same: the coefficient at sin2 in Faye's law is 2.87-2.88 deg/day, while the equatorial rotation rates differ significantly, 0.27 deg/day. On the other hand, an analysis of the longitudinal velocities for the previously revealed two differing populations of sunspot groups has shown that small short-lived groups (SSGs) are associated with the fast rotation mode, while large long-lived groups (LLGs) are associated with both fast and slow modes. The results obtained not only suggest a real physical difference between the two populations of sunspots but also give new empirical data for the development of a dynamo theory, in particular, for the theory of a spatially distributed dynamo.

Genetic structure of Quechua-speakers of the Central Andes and geographic patterns of gene frequencies in South Amerindian populations.

PubMed

Luiselli, D; Simoni, L; Tarazona-Santos, E; Pastor, S; Pettener, D

2000-09-01

A sample of 141 Quechua-speaking individuals of the population of Tayacaja, in the Peruvian Central Andes, was typed for the following 16 genetic systems: ABO, Rh, MNSs, P, Duffy, AcP1, EsD, GLOI, PGM1, AK, 6-PGD, Hp, Gc, Pi, C3, and Bf. The genetic structure of the population was analyzed in relation to the allele frequencies available for other South Amerindian populations, using a combination of multivariate and multivariable techniques. Spatial autocorrelation analysis was performed independently for 13 alleles to identify patterns of gene flow in South America as a whole and in more specific geographic regions. We found a longitudinal cline for the AcP1*a and EsD*1 alleles which we interpreted as the result of an ancient longitudinal expansion of a putative ancestral population of modern Amerindians. Monmonnier's algorithm, used to identify areas of sharp genetic discontinuity, suggested a clear east-west differentiation of native South American populations, which was confirmed by analysis of the distribution of genetic distances. We suggest that this pattern of genetic structures is the consequence of the independent peopling of western and eastern South America or to low levels of gene flow between these regions, related to different environmental and demographic histories. Copyright 2000 Wiley-Liss, Inc.

Budget Impact Analysis to Estimate the Cost Dynamics of Treating Refractory Gastroesophageal Reflux Disease With Radiofrequency Energy: a Payer Perspective.

PubMed

Gregory, David; Scotti, Dennis J; Buck, Daniel; Triadafilopoulos, George

2016-05-01

A minimally invasive endoscopic treatment that utilizes radio-frequency energy (RFE) has received increased attention as an appropriate middle-ground approach in the treatment of refractory gastroesophageal reflux disease (GERD) and as an alternative to complicated and invasive surgical procedures. The objective of this study was to develop a longitudinal budget impact analysis from the payer perspective to estimate the direct medical costs of treatment for the refractory GERD patient population and to estimate the budgetary impact of further extending the RFE treatment option to other target populations. A retrospective analysis of claims designed to assess the longitudinal costs and budget impact on payer expenditures associated with managing and treating GERD surgically (Nissen fundoplication [NF]), endoscopically (RFE), or medically was performed. Both Medicare and commercially insured claims databases were interrogated for such population-level analyses. At current adoption rates (less than 1% of procedures), RFE demonstrated overall cost savings ranging from 7.3% to 50.5% in the 12-month time period following the index procedure (inclusive of procedure costs) when compared to medical management and fundoplication across the commercial and Medicare patient populations. Increasing the total number of RFE procedures to 2% of total cases performed generated per-member, per-month (PMPM) savings of $0.28 in the Medicare population and $0.37 in the commercially insured population. Further increases yielded higher PMPM savings. Adding to the clinical importance of RFE in filling the gap between medical and surgical management, this economic analysis demonstrates to payers that the adoption of RFE can create notable savings to their plans when compared to surgery or medical management.

Longitudinal imaging of Caenorhabditis elegans in a microfabricated device reveals variation in behavioral decline during aging

PubMed Central

Churgin, Matthew A; Jung, Sang-Kyu; Yu, Chih-Chieh; Chen, Xiangmei; Raizen, David M; Fang-Yen, Christopher

2017-01-01

The roundworm C. elegans is a mainstay of aging research due to its short lifespan and easily manipulable genetics. Current, widely used methods for long-term measurement of C. elegans are limited by low throughput and the difficulty of performing longitudinal monitoring of aging phenotypes. Here we describe the WorMotel, a microfabricated device for long-term cultivation and automated longitudinal imaging of large numbers of C. elegans confined to individual wells. Using the WorMotel, we find that short-lived and long-lived strains exhibit patterns of behavioral decline that do not temporally scale between individuals or populations, but rather resemble the shortest and longest lived individuals in a wild type population. We also find that behavioral trajectories of worms subject to oxidative stress resemble trajectories observed during aging. Our method is a powerful and scalable tool for analysis of C. elegans behavior and aging. DOI: http://dx.doi.org/10.7554/eLife.26652.001 PMID:28537553

[Risk factors associated with the conformation of the medial longitudinal arch and the symptomatic flat foot in a metropolitan school population in Mexico].

PubMed

Rivera-Saldívar, G; Torres-González, R; Franco-Valencia, M; Ríos-Monroy, R; Martínez-Ramírez, F; Pérez-Hernández, E; Duarte-Dagnino, D

2012-01-01

The investigation on the medial longitudinal arch is aimed at addressing the diagnostic problems of flat foot. The diagnosis is currently based on clinical tests and the appropriate identification of both postural and gait abnormalities. Risk factors are associated with pre-school ages, but there is no adequate analysis of such factors during school ages, when the longitudinal arch reaches its conformational maturity. Probabilistic methods were used to obtain a sample of 476 patients from elementary schools in the Federal District and the state of Puebla. Once the approval of the research committee was obtained, an analytical, prospective, cross-sectional study was conducted. Anthropometric measurements were performed, together with anamnesis, physical exam of the students, and conventional wet footprint analysis in a standardized and duplicate way. Of the 476 patients, 101 had flat foot (21.2%) and 49 of them had pain symptoms in the feet, knees or both (48.5%), accounting for 10.2% of the patients examined. Forefoot pronation and valgus hindfoot resulted in an increased risk of symptomatic flat foot in the school population in the study. In cases of flat or cavus foot, the presence of foot and/or knee pain symptoms in the school population was associated in a statistically significant way with one or more of the factors analyzed (overweight, genu valgus, valgus hindfoot, forefoot pronation and claw toes). Girls with such factors had a 3-7 higher chance of having symptomatic flat foot.

MIXED MODELS ANALYSIS OR URBANIZATION LEVEL ON CHLORPYRIFOS EXPOSURE

EPA Science Inventory

The National Human Exposure Assessment Survey (NHEXAS) pilot studies were conducted from 1995 through 1997 to examine human population exposure to a wide range of environmental contaminants. In one of the studies, NHEXAS-Maryland, a longitudinal design was used to repeatedly m...

Los Medanos College Fact Book.

ERIC Educational Resources Information Center

MacDonald, Ross; And Others

Prepared to support the self-study and strategic planning processes at Los Medanos College (LMC), in Pittsburgh, California, this fact book offers information about LMC's students, staff, programs, services, facilities, and expenditures. The first section focuses on the student population, including a trend analysis and longitudinal data on…

Asthma caused by occupational exposures is common – A systematic analysis of estimates of the population-attributable fraction

PubMed Central

Torén, Kjell; Blanc, Paul D

2009-01-01

Background The aim of this paper is to highlight emerging data on occupational attributable risk in asthma. Despite well documented outbreaks of disease and the recognition of numerous specific causal agents, occupational exposures previously had been relegated a fairly minor role relative to other causes of adult onset asthma. In recent years there has been a growing recognition of the potential importance of asthma induced by work-related exposures Methods We searched Pub Med from June 1999 through December 2007. We identified six longitudinal general population-based studies; three case-control studies and eight cross-sectional analyses from seven general population-based samples. For an integrated analysis we added ten estimates prior to 1999 included in a previous review. Results The longitudinal studies indicate that 16.3% of all adult-onset asthma is caused by occupational exposures. In an overall synthesis of all included studies the overall median PAR value was 17.6%. Conclusion Clinicians should consider the occupational history when evaluating patients in working age who have asthma. At a societal level, these findings underscore the need for further preventive action to reduce the occupational exposures to asthma-causing agents. PMID:19178702

Mixture Modeling: Applications in Educational Psychology

ERIC Educational Resources Information Center

Harring, Jeffrey R.; Hodis, Flaviu A.

2016-01-01

Model-based clustering methods, commonly referred to as finite mixture modeling, have been applied to a wide variety of cross-sectional and longitudinal data to account for heterogeneity in population characteristics. In this article, we elucidate 2 such approaches: growth mixture modeling and latent profile analysis. Both techniques are…

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

Estimating mono- and bi-phasic regression parameters using a mixture piecewise linear Bayesian hierarchical model

PubMed Central

Zhao, Rui; Catalano, Paul; DeGruttola, Victor G.; Michor, Franziska

2017-01-01

The dynamics of tumor burden, secreted proteins or other biomarkers over time, is often used to evaluate the effectiveness of therapy and to predict outcomes for patients. Many methods have been proposed to investigate longitudinal trends to better characterize patients and to understand disease progression. However, most approaches assume a homogeneous patient population and a uniform response trajectory over time and across patients. Here, we present a mixture piecewise linear Bayesian hierarchical model, which takes into account both population heterogeneity and nonlinear relationships between biomarkers and time. Simulation results show that our method was able to classify subjects according to their patterns of treatment response with greater than 80% accuracy in the three scenarios tested. We then applied our model to a large randomized controlled phase III clinical trial of multiple myeloma patients. Analysis results suggest that the longitudinal tumor burden trajectories in multiple myeloma patients are heterogeneous and nonlinear, even among patients assigned to the same treatment cohort. In addition, between cohorts, there are distinct differences in terms of the regression parameters and the distributions among categories in the mixture. Those results imply that longitudinal data from clinical trials may harbor unobserved subgroups and nonlinear relationships; accounting for both may be important for analyzing longitudinal data. PMID:28723910

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.

Hyperthyroidism is a Risk Factor for Developing Adhesive Capsulitis of the Shoulder: A Nationwide Longitudinal Population-Based Study

PubMed Central

Huang, Shih-Wei; Lin, Jia-Wei; Wang, Wei-Te; Wu, Chin-Wen; Liou, Tsan-Hon; Lin, Hui-Wen

2014-01-01

The purpose of this study was to investigate the prevalence and risk of adhesive capsulitis among hyperthyroidism patients. The data were obtained from the Longitudinal Health Insurance Database 2005 (LHID 2005) in Taiwan, using 1 million participants and a prospective population-based 7-year cohort study of survival analysis. The ambulatory-care claim records of patients diagnosed according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes relating to hyperthyroidism between January 1, 2004 and December 31, 2007, were obtained. The prevalence and the adjusted hazard ratio (HR) of adhesive capsulitis among hyperthyroid patients and the control group were estimated. Of 4472 hyperthyroid patients, 162 (671/100 000 person-years) experienced adhesive capsulitis during the 24 122 person-year follow-up period. The crude HR of stroke was 1.26 (95% confidence interval [CI], 1.06 to 1.49), which was larger than that of the control group. The adjusted HR of developing adhesive capsulitis was 1.22 (95% CI, 1.03 to 1.45) for hyperthyroid patients during the 7-year follow-up period, which achieved statistical significance. The results of our large-scale longitudinal population-based study indicated that hyperthyroidism is an independent risk factor of developing adhesive capsulitis. PMID:24567049

Hyperthyroidism is a risk factor for developing adhesive capsulitis of the shoulder: a nationwide longitudinal population-based study.

PubMed

Huang, Shih-Wei; Lin, Jia-Wei; Wang, Wei-Te; Wu, Chin-Wen; Liou, Tsan-Hon; Lin, Hui-Wen

2014-02-25

The purpose of this study was to investigate the prevalence and risk of adhesive capsulitis among hyperthyroidism patients. The data were obtained from the Longitudinal Health Insurance Database 2005 (LHID 2005) in Taiwan, using 1 million participants and a prospective population-based 7-year cohort study of survival analysis. The ambulatory-care claim records of patients diagnosed according to the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes relating to hyperthyroidism between January 1, 2004 and December 31, 2007, were obtained. The prevalence and the adjusted hazard ratio (HR) of adhesive capsulitis among hyperthyroid patients and the control group were estimated. Of 4472 hyperthyroid patients, 162 (671/100,000 person-years) experienced adhesive capsulitis during the 24,122 person-year follow-up period. The crude HR of stroke was 1.26 (95% confidence interval [CI], 1.06 to 1.49), which was larger than that of the control group. The adjusted HR of developing adhesive capsulitis was 1.22 (95% CI, 1.03 to 1.45) for hyperthyroid patients during the 7-year follow-up period, which achieved statistical significance. The results of our large-scale longitudinal population-based study indicated that hyperthyroidism is an independent risk factor of developing adhesive capsulitis.

Risk and Protective Factors for Educational Achievement among Serious Offending Girls

ERIC Educational Resources Information Center

Oudekerk, Barbara A.; Chauhan, Preeti; Reppucci, N. Dickon

2012-01-01

Using longitudinal data, this analysis: (1) documented educational outcomes for serious offending girls, and (2) identified risk and protective factors associated with academic achievement in mid-adolescence and degree attainment by early adulthood. In mid-adolescence, girls performed nearly one standard deviation below the population mean on…

Against Conventional Wisdom: Factors Influencing Hispanic Students' Reading Achievement

ERIC Educational Resources Information Center

Percell, Jay C.; Kaufman, Kristina

2013-01-01

The researchers performed a variable analysis of the 2002 Educational Longitudinal Study data investigating factors that influence students' reading scores on standardized tests. Hispanic and non-Hispanic Scores were analyzed and controlling variables were compared to determine the effect of each on both populations. Certain variables commonly…

Identifying and separating the effects of practice and of cognitive ageing during a large longitudinal study of elderly community residents.

PubMed

Rabbitt, P; Diggle, P; Smith, D; Holland, F; Mc Innes, L

2001-01-01

In protracted longitudinal studies of cognitive changes in old age volunteers must be repeatedly tested. Even with intervals of several years between assessment, this raises the possibility that improvements due to practice mask other changes. This problem is much more acute in brief studies of cognitive changes associated with progressive pathologies such as Alzheimer's disease or the effects of clinical interventions. Both types of study also encounter problems of selective dropout of frail and less able individuals leaving relatively 'elite' survivors. An analysis of data from repeated testing at 2-3 years intervals on the AH4 (1) intelligence test is presented to illustrate how a random effects model can be used to identify and disassociate age-related changes and practice effects at the population level, after effects of selective dropout and of background demographical variables have been taken into consideration. This analysis also provides some new, substantive empirical findings. Age-related changes are relatively slight between 49 and 70 years but much more marked between 70 and 80 years. Even with assessment points, several years apart the population average effect of practice is large relative to that of age-related change. Variation between individuals increases as samples age, providing the first clear evidence from a longitudinal study for marked individual differences in trajectories of cognitive ageing.

The reduction of health care costs associated with alcoholism treatment: a 14-year longitudinal study.

PubMed

Holder, H D; Blose, J O

1992-07-01

This study utilized two separate research designs to examine whether the initiation of alcoholism treatment is associated with a change in overall medical care cost in a population of alcoholics enrolled under a health plan sponsored by a large midwestern manufacturing corporation. In the longest longitudinal study of alcoholism treatment costs to date, a review of claims filed from 1974 to 1987 identified 3,729 alcoholics (3,068 of whom received treatment and 661 of whom did not). In one design, a time-series analysis found that following treatment initiation the total health care costs of treated alcoholics--including the cost of alcoholism treatment--declined by 23% to 55% from their highest pretreatment levels. Costs for identified but untreated alcoholics rose following identification. In a second design, analysis of variance was used to control for group differences including pretreatment health status and age. This analysis indicated that the posttreatment costs of treated alcoholics were 24% lower than comparable costs for untreated alcoholics. The study provides considerable evidence that alcoholism treatment can reduce overall medical costs in a heterogeneous alcoholic population (white collar/blue collar; fee-for-service/HMO).

First genealogy for a wild marine fish population reveals multigenerational philopatry.

PubMed

Salles, Océane C; Pujol, Benoit; Maynard, Jeffrey A; Almany, Glenn R; Berumen, Michael L; Jones, Geoffrey P; Saenz-Agudelo, Pablo; Srinivasan, Maya; Thorrold, Simon R; Planes, Serge

2016-11-15

Natal philopatry, the return of individuals to their natal area for reproduction, has advantages and disadvantages for animal populations. Natal philopatry may generate local genetic adaptation, but it may also increase the probability of inbreeding that can compromise persistence. Although natal philopatry is well documented in anadromous fishes, marine fish may also return to their birth site to spawn. How philopatry shapes wild fish populations is, however, unclear because it requires constructing multigenerational pedigrees that are currently lacking for marine fishes. Here we present the first multigenerational pedigree for a marine fish population by repeatedly genotyping all individuals in a population of the orange clownfish (Amphiprion percula) at Kimbe Island (Papua New Guinea) during a 10-y period. Based on 2927 individuals, our pedigree analysis revealed that longitudinal philopatry was recurrent over five generations. Progeny tended to settle close to their parents, with related individuals often sharing the same colony. However, successful inbreeding was rare, and genetic diversity remained high, suggesting occasional inbreeding does not impair local population persistence. Local reproductive success was dependent on the habitat larvae settled into, rather than the habitat they came from. Our study suggests that longitudinal philopatry can influence both population replenishment and local adaptation of marine fishes. Resolving multigenerational pedigrees during a relatively short period, as we present here, provides a framework for assessing the ability of marine populations to persist and adapt to accelerating climate change.

First genealogy for a wild marine fish population reveals multigenerational philopatry

PubMed Central

Salles, Océane C.; Pujol, Benoit; Maynard, Jeffrey A.; Almany, Glenn R.; Berumen, Michael L.; Jones, Geoffrey P.; Saenz-Agudelo, Pablo; Srinivasan, Maya; Thorrold, Simon R.; Planes, Serge

2016-01-01

Natal philopatry, the return of individuals to their natal area for reproduction, has advantages and disadvantages for animal populations. Natal philopatry may generate local genetic adaptation, but it may also increase the probability of inbreeding that can compromise persistence. Although natal philopatry is well documented in anadromous fishes, marine fish may also return to their birth site to spawn. How philopatry shapes wild fish populations is, however, unclear because it requires constructing multigenerational pedigrees that are currently lacking for marine fishes. Here we present the first multigenerational pedigree for a marine fish population by repeatedly genotyping all individuals in a population of the orange clownfish (Amphiprion percula) at Kimbe Island (Papua New Guinea) during a 10-y period. Based on 2927 individuals, our pedigree analysis revealed that longitudinal philopatry was recurrent over five generations. Progeny tended to settle close to their parents, with related individuals often sharing the same colony. However, successful inbreeding was rare, and genetic diversity remained high, suggesting occasional inbreeding does not impair local population persistence. Local reproductive success was dependent on the habitat larvae settled into, rather than the habitat they came from. Our study suggests that longitudinal philopatry can influence both population replenishment and local adaptation of marine fishes. Resolving multigenerational pedigrees during a relatively short period, as we present here, provides a framework for assessing the ability of marine populations to persist and adapt to accelerating climate change. PMID:27799530

Physical exercise and cognitive function across the life span: Results of a nationwide population-based study.

PubMed

Gaertner, Beate; Buttery, Amanda K; Finger, Jonas D; Wolfsgruber, Steffen; Wagner, Michael; Busch, Markus A

2018-05-01

To examine cross-sectional and longitudinal associations between physical exercise and cognitive function across different age groups in a nationwide population-based sample of adults aged 18-79 years in Germany. Cross-sectional/prospective. Cognitive function was assessed in the mental health module of the German Health Interview and Examination Survey for Adults (DEGS1-MH, 2009-2012, n=3535), using a comprehensive neuropsychological test battery. Cognitive domain scores for executive function and memory were derived from confirmatory factor analysis. Regular physical exercise in the last three months was assessed by self-report and defined as no exercise, <2 and ≥2h (hours) of exercise per week. A subgroup of DEGS1-MH participants who previously participated in the German National Health Interview and Examination Survey 1998 (GNHIES98, 1997-1999, n=1624) enabled longitudinal analyses with a mean follow-up of 12.4 years. Compared to no exercise, more weekly physical exercise was associated with better executive function in cross-sectional (<2h: β=0.12; ≥2h: β=0.17; all p<0.001) and longitudinal analyses (<2h: β=0.14, p<0.001; ≥2h: β=0.15, p=0.001) using linear regression models adjusted for age, sex, education, smoking, alcohol consumption, fruit and vegetable consumption and obesity. Slightly weaker associations were found for memory in cross-sectional (<2h: β=0.08, p=0.009; ≥2h: β=0.08, p=0.026) and longitudinal analysis (<2h: β=0.09, p=0.036; ≥2h: β=0.08, p=0.114). There was no evidence of interaction between physical exercise and age. Higher levels of physical exercise were associated with better executive function and memory in cross-sectional and longitudinal analyses with no evidence for differential effects by age. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Disability Measurement for Korean Community-Dwelling Adults With Stroke: Item-Level Psychometric Analysis of the Korean Longitudinal Study of Ageing

PubMed Central

2018-01-01

Objective To investigate the psychometric properties of the activities of daily living (ADL) instrument used in the analysis of Korean Longitudinal Study of Ageing (KLoSA) dataset. Methods A retrospective study was carried out involving 2006 KLoSA records of community-dwelling adults diagnosed with stroke. The ADL instrument used for the analysis of KLoSA included 17 items, which were analyzed using Rasch modeling to develop a robust outcome measure. The unidimensionality of the ADL instrument was examined based on confirmatory factor analysis with a one-factor model. Item-level psychometric analysis of the ADL instrument included fit statistics, internal consistency, precision, and the item difficulty hierarchy. Results The study sample included a total of 201 community-dwelling adults (1.5% of the Korean population with an age over 45 years; mean age=70.0 years, SD=9.7) having a history of stroke. The ADL instrument demonstrated unidimensional construct. Two misfit items, money management (mean square [MnSq]=1.56, standardized Z-statistics [ZSTD]=2.3) and phone use (MnSq=1.78, ZSTD=2.3) were removed from the analysis. The remaining 15 items demonstrated good item fit, high internal consistency (person reliability=0.91), and good precision (person strata=3.48). The instrument precisely estimated person measures within a wide range of theta (−4.75 logits < θ < 3.97 logits) and a reliability of 0.9, with a conceptual hierarchy of item difficulty. Conclusion The findings indicate that the 15 ADL items met Rasch expectations of unidimensionality and demonstrated good psychometric properties. It is proposed that the validated ADL instrument can be used as a primary outcome measure for assessing longitudinal disability trajectories in the Korean adult population and can be employed for comparative analysis of international disability across national aging studies. PMID:29765888

Prognostic Significance of Spot Urine Na/K for Longitudinal Changes in Blood Pressure and Renal Function: The Nagahama Study.

PubMed

Tabara, Yasuharu; Takahashi, Yoshimitsu; Setoh, Kazuya; Kawaguchi, Takahisa; Kosugi, Shinji; Nakayama, Takeo; Matsuda, Fumihiko

2017-09-01

Urinary sodium-to-potassium ratio (Na/K) represents a simple measure of sodium load and has been reported to be associated with blood pressure (BP) levels in a cross-sectional setting even with spot measurements. The aim of the present large-scale cohort study is to determine prognostic significance of spot urine Na/K for longitudinal changes in BP levels and renal function. The present study population consisted of 7,063 individuals from the general population. Clinical parameters were measured at baseline and at a follow-up interval of 5 years. Mean systolic BP was slightly increased during the follow-up period (overall, 124 ± 17 to 125 ± 18 mm Hg; nontreated participants, 119 ± 15 to 122 ± 17 mm Hg). Although, the urinary Na/K demonstrated a linear association with BP in a cross-sectional analysis (P < 0.001), analysis of repeated measured BP values identified baseline Na/K * time interaction, i.e., an intraindividual effect, as an inverse determinant (F = 76.9, P < 0.001) independently of hypertension status and fasting conditions possibly due to regression to the mean of temporary high baseline Na/K values at baseline. Spot urine Na/K values were found to be positively associated with renal function in a cross-sectional analysis (P < 0.001). Although baseline Na/K * time interaction showed inverse associated with renal functional decline (F = 85.8, P < 0.001), this inverse association might not represent physiological relationship in likewise fashion with the analysis for BP. Spot urine Na/K may have limited utility as a prognostic marker of longitudinal BP change, as well as renal functional decline. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

The Sociocultural Factors of Russian Stagnation and Modernization

ERIC Educational Resources Information Center

Lapin, N. I.

2012-01-01

An analysis of the results of six Russian Longitudinal Monitoring Surveys, "The Values and Interests of the Population of Russia" (1990, 1994, 1998, 2002, 2006, and 2010), conducted by the Center for the Study of Sociocultural Changes at the Institute of Philosophy, Russian Academy of Sciences, provides evidence that two stages in the…

Multiple Trajectories of Successful Aging of Older and Younger Cohorts

ERIC Educational Resources Information Center

Hsu, Hui-Chuan; Jones, Bobby L.

2012-01-01

Purpose: The purpose of this study was to apply group-based trajectory analysis to identify multiple successful aging trajectories by multiple indicators and to examine the factors related to successful aging among the elderly population in Taiwan. Design and Methods: Nation-representative longitudinal data collected from 1993 to 2007 and…

Application of a large electronic health record database to study effects of air quality on mortality in a heart failure population

EPA Science Inventory

Background: Electronic health records (EHRs) are now a ubiquitous component of the US healthcare system and are attractive for secondary data analysis as they contain detailed and longitudinal clinical records on potentially millions of individuals. However, due to their relative...

The American Freshman: National Norms for Fall 2000.

ERIC Educational Resources Information Center

Sax, Linda J.; Astin, Alexander W.; Korn, William S.; Mahoney, Kathryn M.

This 35th annual report of national normative data on college freshmen is part of the Cooperative Institutional Research Program (CIRP) longitudinal study to assess the effects of college on students. The freshman data reported here are weighted to provide a normative profile of the U.S. freshman population for use in policy analysis, human…

Longitudinal associations of intimate partner violence attitudes and perpetration: Dyadic couples data from a randomized controlled trial in rural India

PubMed Central

Shakya, Holly B.; Fleming, Paul; Saggurti, Niranjan; Donta, Balaiah; Silverman, Jay; Raj, Anita

2018-01-01

We conducted longitudinal analyses examining the associations between intimate partner violence (IPV) attitudes and women’s reported IPV in couples (N = 762) using 3 waves of data from a randomized controlled trial in Maharashtra, India. We found that, between Waves 1 and 2, men’s and women’s acceptance of IPV in the overall population decreased significantly while reports of IPV increased. These changes, we hypothesize, are evidence of an exogenous shock, possibly a high profile rape in Delhi in December 2012, that may have impacted the entire population. Cross-sectional associations between men’s attitudes towards IPV and reported IPV were not significant in Wave 1, while positively and significantly associated in Waves 2 and 3. Longitudinal analysis showed that reduction in men’s acceptance of IPV between Waves 1 and 2 was associated with a lower likelihood of reported IPV in Wave 3. Women’s Wave 1 acceptance of IPV was positively associated with reported IPV in the Wave 1 cross-sectional analysis, while Wave 2 and Wave 3 measures of IPV acceptance were negatively associated with reported IPV in Waves 2 and 3 respectively. Longitudinal analyses of the change in women’s attitudes towards IPV from Wave 1 to 2 and reported IPV in Wave 3 were insignificant. However, When women first reported IPV in Waves 2 or 3 they were less likely to report acceptance of IPV in that same wave. Findings suggest that changes in husbands’ IPV acceptance is predictive of subsequent IPV, while newly experienced IPV predicts decreased IPV acceptance for women. Wave 2 and Wave 3 results were significant for the control group only, evidence that the intervention affected those associations, potentially changing attitudes more quickly than behavior. We recommend interventions that expose community opposition to IPV as a new social norm, and analysis of how the 2012 Delhi rape case may have affected these norms. PMID:28260640

Two-dimensional speckle-tracking strain echocardiography in long-term heart transplant patients: a study comparing deformation parameters and ejection fraction derived from echocardiography and multislice computed tomography.

PubMed

Syeda, Bonni; Höfer, Peter; Pichler, Philipp; Vertesich, Markus; Bergler-Klein, Jutta; Roedler, Susanne; Mahr, Stephane; Goliasch, Georg; Zuckermann, Andreas; Binder, Thomas

2011-07-01

Longitudinal strain determined by speckle tracking is a sensitive parameter to detect systolic left ventricular dysfunction. In this study, we assessed regional and global longitudinal strain values in long-term heart transplants and compared deformation indices with ejection fraction as determined by transthoracic echocardiography (TTE) and multislice computed tomographic coronary angiography (MSCTA). TTE and MSCTA were prospectively performed in 31 transplant patients (10.6 years post-transplantation) and in 42 control subjects. Grey-scale apical views were recorded for speckle tracking (EchoPAC 7.0, GE) of the 16 segments of the left ventricle. The presence of coronary artery disease (CAD) was assessed by MSCTA. Strain analysis was performed in 1168 segments [496 in transplant patients (42.5%), 672 in control subjects (57.7%)]. Global longitudinal peak systolic strain was significantly lower in the transplant recipients than in the healthy population (-13.9 ± 4.2 vs. -17.4 ± 5.8%, P< 0.01). This was still the case after exclusion of the nine transplant patients with CAD (-14.1 ± 4.4 vs. -17.4 ± 5.8%, P=0.03). Transplant patients exhibited significantly lower regional strain values in 9 of the 16 segments. Left ventricular ejection fraction (%) (MSCTA/Simpsons method) was 60.7 ± 10.1%/60.2 ± 6.7% in transplant recipients vs. 64.7 ± 6.4%/63.0 ± 6.2% in the healthy population, P=ns. Even though 'healthy' heart transplants without CAD exhibit normal ejection fraction, deformation indices are reduced in this population when compared with control subjects. Our findings suggests that strain analysis is more sensitive than assessment of ejection fraction for the detection of abnormalities of systolic function.

The ONS Longitudinal Study--a prestigious past and a bright future.

PubMed

Goldring, Shayla; Newman, Jim

2010-01-01

This issue of Population Trends includes a number of articles and reports resulting from research based on the ONS Longitudinal Study (ONS LS). They have been drawn together in one issue to highlight the value of this type of study for demographic research.2009 marked the 35th anniversary of the establishment of the ONS LS. The study now contains data from the last four censuses (1971 to 2001), linked to vital events data since 1971, for a sample of one per cent of the population of England and Wales.More recently, sister studies have been established in Scotland and Northern Ireland. The Scottish Longitudinal Study (SLS) started with 1991 Census data and the Northern Ireland Longitudinal Study (NILS)started with 2001 Census data.The lead article in this issue comes from an exemplar project that was established to explore how to utilise the three studies to carry out UK-wide longitudinal analysis. Two different methods were used to analyse socio-economic and country level differences in health and mortality across the studies. The article summarises the results of this analysis, reports on the relative strengths of the different methods used, and draws attention to a number of new resources that have been developed by the project researchers as aids to using all three studies.This is an excellent example of collaborative working across the UK, involving researchers from the Centre for Longitudinal Study Information and User Support (CeLSIUS) at the London School of Hygiene and Tropical Medicine, the Longitudinal Studies Centre - Scotland (LSCS) at the University of St.Andrews and the Northern Ireland Longitudinal Study - Research Support Unit (NILS-RSU) at Queen's University Belfast. The project also involved collaboration between ONS, the General Register Office for Scotland (GROS) and the Northern Ireland Statistics and Research Agency (NISRA) to ensure the secure transfer and handling of data from the three studies so that it could be brought together in one place for analysis.The other ONS LS-based articles and reports in this edition largely focus on research into issues related to families and households, as summarised below: A collaborative project involving Ben Wilson (ONS) and Rachel Stuchbury (CeLSIUS) comparing the stability of partnerships involving marriage and cohabitation.A project looking at transitions in children's experience of living in a workless household and how this varies by ethnic group, submitted by Lucinda Platt (Institute for Social & Economic Research, University of Essex).An article on the effect of a change in the census definition of a child between 1991 and 2001 submitted by Emily Grundy, Rachel Stuchbury and Harriet Young (CeLSIUS).The remainder of this introductory article will focus on the ONS LS, its history and some examples of its use, and gives a summary of planned developments over the coming years. Please refer to the contact details at the end of the article if you require further information on any of the three longitudinal studies.

Socio-economic position and common mental disorders. Longitudinal study in the general population in the UK.

PubMed

Skapinakis, Petros; Weich, Scott; Lewis, Glyn; Singleton, Nicola; Araya, Ricardo

2006-08-01

Individuals in lower socio-economic groups have an increased prevalence of common mental disorders. To investigate the longitudinal association between socio-economic position and common mental disorders in a general population sample in the UK. Participants (n=2406) were assessed at two time points 18 months apart with the Revised Clinical Interview Schedule. The sample was stratified into two cohorts according to mental health status at baseline. None of the socio-economic indicators studied was significantly associated with an episode of common mental disorder at follow-up after adjusting for baseline psychiatric morbidity. The analysis of separate diagnostic categories showed that subjective financial difficulties at baseline were independently associated with depression at follow-up in both cohorts. These findings support the view that apart from objective measures of socio-economic position, more subjective measures might be equally important from an aetiological or clinical perspective.

Risk factors for common mental disorders in women. Population-based longitudinal study.

PubMed

Patel, Vikram; Kirkwood, Betty R; Pednekar, Sulochana; Weiss, Helen; Mabey, David

2006-12-01

The determinants of common mental disorders in women have not been described in longitudinal studies from a low-income country. Population-based cohort study of 2494 women aged 18 to 50 years, in India. The Revised Clinical Interview Schedule was used for the detection of common mental disorders. There were 39 incident cases of common mental disorder in 2166 participants eligible for analysis (12-month rate 1.8%, 95% CI 1.3-2.4%). The following baseline factors were independently associated with the risk for common mental disorder: poverty (low income and having difficulty making ends meet); being married as compared with being single; use of tobacco; experiencing abnormal vaginal discharge; reporting a chronic physical illness; and having higher psychological symptom scores at baseline. Programmes to reduce the burden of common mental disorder in women should target poorer women, women with chronic physical illness and who have gynaecological symptoms, and women who use tobacco.

Physical activity and asthma: A longitudinal and multi-country study.

PubMed

Russell, Melissa A; Janson, Christer; Real, Francisco Gómez; Johannessen, Ane; Waatevik, Marie; Benediktsdóttir, Bryndis; Holm, Mathias; Lindberg, Eva; Schlünssen, Vivi; Raza, Wasif; Dharmage, Shyamali C; Svanes, Cecilie

2017-11-01

To investigate the impact of physical activity on asthma in middle-aged adults, in one longitudinal analysis, and one multi-centre cross-sectional analysis. The Respiratory Health in Northern Europe (RHINE) is a population-based postal questionnaire cohort study. Physical activity, height and weight were self-reported in Bergen, Norway, at RHINE II (1999-2001) and all centres at RHINE III (2010-2012). A longitudinal analysis of Bergen data investigated the association of baseline physical activity with follow-up asthma, incident asthma and symptoms, using logistic and zero-inflated Poisson regression (n = 1782). A cross-sectional analysis of all RHINE III centres investigated the association of physical activity with concurrent asthma and symptoms (n = 13,542) using mixed-effects models. Body mass index (BMI) was categorised (<20, 20-24.99, 25-29.99, 30+ kg/m 2 ) and physical activity grouped by amount and frequency of lighter (no sweating/heavy breathing) and vigorous (sweating/heavy breathing) activity. In the Bergen longitudinal analysis, undertaking light activity 3+ times/week at baseline was associated with less follow-up asthma (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.22, 0.89), whilst an effect from undertaking vigorous activity 3+ times/week was not detected (OR 1.22, 95% CI 0.44, 2.76). The associations were attenuated with BMI adjustment. In the all-centre cross-sectional analysis an interaction was found, with the association between physical activity and asthma varying across BMI categories. These findings suggest potential longer-term benefit from lighter physical activity, whilst improvement in asthma outcomes from increasing activity intensity was not evident. Additionally, it appears the benefit from physical activity may differ according to BMI.

Influence of Social Engagement on Mortality in Korea: Analysis of the Korean Longitudinal Study of Aging (2006-2012).

PubMed

Kim, Jae-Hyun; Lee, Sang Gyu; Kim, Tae-Hyun; Choi, Young; Lee, Yunhwan; Park, Eun-Cheol

2016-07-01

The objective of this study was to investigate the impact of social engagement and patterns of change in social engagement over time on mortality in a large population, aged 45 years or older. Data from the Korean Longitudinal Study of Aging from 2006 and 2012 were assessed using longitudinal data analysis. We included 8,234 research subjects at baseline (2006). The primary analysis was based on Cox proportional hazards models to examine our hypothesis. The hazard ratio of all-cause mortality for the lowest level of social engagement was 1.841-times higher (P < 0.001) compared with the highest level of social engagement. Subgroup analysis results by gender showed a similar trend. A six-class linear solution fit the data best, and class 1 (the lowest level of social engagement class, 7.6% of the sample) was significantly related to the highest mortality (HR: 4.780, P < 0.001). Our results provide scientific insight on the effects of the specificity of the level of social engagement and changes in social engagement on all-cause mortality in current practice, which are important for all-cause mortality risk. Therefore, protection from all-cause mortality may depend on avoidance of constant low-levels of social engagement.

Predictors of Disordered Eating in Adolescence and Young Adulthood: A Population-Based, Longitudinal Study of Females and Males in Norway

ERIC Educational Resources Information Center

Abebe, Dawit Shawel; Torgersen, Leila; Lien, Lars; Hafstad, Gertrud S.; von Soest, Tilmann

2014-01-01

We investigated longitudinal predictors for disordered eating from early adolescence to young adulthood (12-34 years) across gender and different developmental phases among Norwegian young people. Survey data from a population-based sample were collected at four time points (T) over a 13-year time span. A population-based sample of 5,679 females…

The Australian longitudinal study on male health sampling design and survey weighting: implications for analysis and interpretation of clustered data.

PubMed

Spittal, Matthew J; Carlin, John B; Currier, Dianne; Downes, Marnie; English, Dallas R; Gordon, Ian; Pirkis, Jane; Gurrin, Lyle

2016-10-31

The Australian Longitudinal Study on Male Health (Ten to Men) used a complex sampling scheme to identify potential participants for the baseline survey. This raises important questions about when and how to adjust for the sampling design when analyzing data from the baseline survey. We describe the sampling scheme used in Ten to Men focusing on four important elements: stratification, multi-stage sampling, clustering and sample weights. We discuss how these elements fit together when using baseline data to estimate a population parameter (e.g., population mean or prevalence) or to estimate the association between an exposure and an outcome (e.g., an odds ratio). We illustrate this with examples using a continuous outcome (weight in kilograms) and a binary outcome (smoking status). Estimates of a population mean or disease prevalence using Ten to Men baseline data are influenced by the extent to which the sampling design is addressed in an analysis. Estimates of mean weight and smoking prevalence are larger in unweighted analyses than weighted analyses (e.g., mean = 83.9 kg vs. 81.4 kg; prevalence = 18.0 % vs. 16.7 %, for unweighted and weighted analyses respectively) and the standard error of the mean is 1.03 times larger in an analysis that acknowledges the hierarchical (clustered) structure of the data compared with one that does not. For smoking prevalence, the corresponding standard error is 1.07 times larger. Measures of association (mean group differences, odds ratios) are generally similar in unweighted or weighted analyses and whether or not adjustment is made for clustering. The extent to which the Ten to Men sampling design is accounted for in any analysis of the baseline data will depend on the research question. When the goals of the analysis are to estimate the prevalence of a disease or risk factor in the population or the magnitude of a population-level exposure-outcome association, our advice is to adopt an analysis that respects the sampling design.

Age, Gender, and Race-Based Coronary Artery Calcium Score Percentiles in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

PubMed

Pereira, Alexandre C; Gomez, Luz M; Bittencourt, Marcio Sommer; Staniak, Henrique Lane; Sharovsky, Rodolfo; Foppa, Murilo; Blaha, Michael J; Bensenor, Isabela M; Lotufo, Paulo A

2016-06-01

Coronary artery calcium (CAC) has been demonstrated to independently predict the risk of cardiovascular events and all-cause mortality, especially among White populations. Although the population distribution of CAC has been determined for several White populations, the distribution in ethnically admixed groups has not been well established. The CAC distribution, stratified for age, gender and race, is similar to the previously described distribution in the MESA study. The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a prospective cohort study designed to investigate subclinical cardiovascular disease in 6 different centers of Brazil. Similar to previous studies, individuals with self-reported coronary or cerebrovascular disease and those treated for diabetes mellitus were excluded from analysis. Percentiles of CAC distribution were estimated with nonparametric techniques. The analysis included 3616 individuals (54% female; mean age, 50 years). As expected, CAC prevalence and burden were steadily higher with increasing age, as well as increased in men and in White individuals. Our results revealed that for a given CAC score, the ELSA-derived CAC percentile would be lower in men compared with the Multi-Ethnic Study of Atherosclerosis (MESA) and would be higher in women compared with MESA. In our sample of the Brazilian population, we observed significant differences in CAC by sex, age, and race. Adjusted for age and sex, low-risk individuals from the Brazilian population present with significantly lower CAC prevalence and burden compared with other low-risk individuals from other worldwide populations. Using US-derived percentiles in Brazilian individuals may lead to overestimating relative CAC burden in men and underestimating relative CAC burden in women. © 2016 Wiley Periodicals, Inc.

Understanding Individual-Level Change through the Basis Functions of a Latent Curve Model

ERIC Educational Resources Information Center

Blozis, Shelley A.; Harring, Jeffrey R.

2017-01-01

Latent curve models have become a popular approach to the analysis of longitudinal data. At the individual level, the model expresses an individual's response as a linear combination of what are called "basis functions" that are common to all members of a population and weights that may vary among individuals. This article uses…

Recidivism among High-Risk Drug Felons: A Longitudinal Analysis following Residential Treatment

ERIC Educational Resources Information Center

Belenko, Steven; Foltz, Carol; Lang, Michelle A.; Sung, Hung-En

2004-01-01

Recent interest in increasing access to substance abuse treatment for drug-involved offenders has been spurred by concerns over expanding prison and jail populations, high recidivism rates for drug-involved offenders, and the close link between illegal drug use and criminal activity. Chronic untreated drug and alcohol abuse is likely to result in…

Adolescent Tobacco and Cannabis Use: Young Adult Outcomes from the Ontario Child Health Study

ERIC Educational Resources Information Center

Georgiades, Katholiki; Boyle, Michael H.

2007-01-01

Background: This study examines the longitudinal associations between adolescent tobacco and cannabis use and young adult functioning. Methods: Data for analysis come from the Ontario Child Health Study (OCHS), a prospective study of child health, psychiatric disorder and adolescent substance use in a general population sample that began in 1983,…

Characteristics of Specialists' Adaptation to the Conditions of a Society in Transformation

ERIC Educational Resources Information Center

Nizamova, A. E.

2012-01-01

The declining size of the Russian population means that labor resources need to be used more effectively, which is especially true of highly skilled workers. An analysis of data from the Russian Longitudinal Monitoring Survey (RLMS) shows that the social and workplace situations of specialists need to be improved significantly. (Contains 5 tables…

The Mutual Relationship Between Men's Drinking and Depression: A 4-Year Longitudinal Analysis.

PubMed

Lee, Soo Bi; Chung, Sulki; Lee, HaeKook; Seo, Jeong Seok

2018-03-17

The purpose of the current study was to examine the longitudinal reciprocal relationship between depression and drinking among male adults from the general population. This study used a panel dataset from the Korean Welfare Panel (from 2011 to 2014). The subjects were 2511 male adults aged between 20 and 65 years. Based on the Korean Version of the Alcohol Use Disorders Identification Test (AUDIT-K) scores, 2191 subjects were categorized as the control group (AUDIT-K < 12) and 320 subjects were categorized as the problem drinking group (AUDIT-K ≥ 12). An autoregressive cross-lagged modelling analysis was performed to investigate the mutual relationship between problem drinking and depression measured consecutively over time. The results indicated that alcohol drinking and depression were stable over time. In the control group, there was no significant causal relationship between problem drinking and depression while in the problem drinking group, drinking in the previous year significantly influenced depression in the following second, third and fourth years. This study compared normal versus problem drinkers and showed a 4-year mutual causal relationship between depression and drinking. No longitudinal interaction between drinking and depression occurred in normal drinkers, while drinking intensified depression over time in problem drinkers. This study found that problem drinking was a risk factor for development of depression. Therefore, more attention should be given to problem alcohol use in the general population and evaluation of past alcohol use history in patients with depressive disorders.

Longitudinal differentiation among pelagic populations in a planktic foraminifer

PubMed Central

Ujiié, Yurika; Asami, Takahiro; de Garidel-Thoron, Thibault; Liu, Hui; Ishitani, Yoshiyuki; de Vargas, Colomban

2012-01-01

Evolutionary processes in marine plankton have been assumed to be dependent on the oceanic circulation system, which transports plankton between populations in marine surface waters. Gene flow facilitated by oceanic currents along longitudinal gradients may efficiently impede genetic differentiation of pelagic populations in the absence of confounding marine environmental effects. However, how responsible oceanic currents are for the geographic distribution and dispersal of plankton is poorly understood. We examined the phylogeography of the planktic foraminifer Pulleniatina obliquiloculata in the Indo-Pacific Warm Pool (IPWP) by using partial small subunit ribosomal DNA (SSU rDNA) sequences. We found longitudinal clines in the frequencies of three distinct genetic types in the IPWP area. These frequencies were correlated with environmental factors that are characteristic of three water masses in the IPWP. Noteworthy, populations inhabiting longitudinally distant water masses at the Pacific and Indian sides of the IPWP were genetically different, despite transportation of individuals via oceanic currents. These results demonstrate that populations of pelagic plankton have diverged genetically among different water masses within a single climate zone. Changes of the oceanic circulation system could have impacted the geographic patterns of dispersal and divergence of pelagic plankton. PMID:22957176

Can a bank crisis break your heart?

PubMed Central

Stuckler, David; Meissner, Christopher M; King, Lawrence P

2008-01-01

Background To assess whether a banking system crisis increases short-term population cardiovascular mortality rates. Methods International, longitudinal multivariate regression analysis of cardiovascular disease mortality data from 1960 to 2002 Results A system-wide banking crisis increases population heart disease mortality rates by 6.4% (95% CI: 2.5% to 10.2%, p < 0.01) in high income countries, after controlling for economic change, macroeconomic instability, and population age and social distribution. The estimated effect is nearly four times as large in low income countries. Conclusion Banking crises are a significant determinant of short-term increases in heart disease mortality rates, and may have more severe consequences for developing countries. PMID:18197979

Longitudinal Change in Telomere Length and the Chronic Stress Response in a Randomized Pilot Biobehavioral Clinical Study: Implications for Cancer Prevention

PubMed Central

Biegler, Kelly A.; Anderson, Amanda K. L.; Wenzel, Lari B.; Osann, Kathryn; Nelson, Edward L.

2015-01-01

Shortened telomere length is associated with increased cancer incidence and mortality. Populations experiencing chronic stress have accelerated telomere shortening. In this exploratory study, we examined associations between longitudinal changes in patient reported outcomes (PRO) of psychologic distress and peripheral blood mononuclear cell (PBMC) telomere length to test the hypothesis that modulation of the chronic stress response would also modulate telomere dynamics. Archived PBMC specimens (N = 22) were analyzed from a completed and reported randomized, longitudinal trial that showed a psychosocial telephone counseling intervention improved quality of life (QOL) and modulated stress-associated biomarkers in cervical cancer survivors. PROs and biospecimens were collected at baseline and 4 months postenrollment. Telomere length of archived PBMCs was evaluated using the flow-FISH assay. Longitudinal changes in psychologic distress, measured by the Brief Symptom Inventory-18, were significantly associated with increased telomere length within the CD14+ (monocyte) population (r = 0.46, P = 0.043); a similar trend was observed for the CD14− population. Longitudinal changes in telomere length of the CD14− subset, primarily T lymphocytes, were associated with longitudinal increases in the naive T-cell population (r = 0.49, P = 0.052). Alterations in the chronic stress response were associated with modulation of telomere length in PBMCs, with evidence for mobilization of “younger” cells from progenitor populations. These data provide preliminary support for the (i) capacity to modulate the chronic stress response and the associated accelerated telomere shortening, (ii) inclusion of telomere length in the biobehavioral paradigm, and (iii) potential link between the chronic stress response and biologic mechanisms responsible for genomic integrity and carcinogenesis. PMID:22827974

Crash and rebound of indigenous populations in lowland South America

NASA Astrophysics Data System (ADS)

Hamilton, Marcus J.; Walker, Robert S.; Kesler, Dylan C.

2014-04-01

Lowland South America has long been a battle-ground between European colonization and indigenous survival. Initial waves of European colonization brought disease epidemics, slavery, and violence that had catastrophic impacts on indigenous cultures. In this paper we focus on the demography of 238 surviving populations in Brazil. We use longitudinal censuses from all known indigenous Brazilian societies to quantify three demographic metrics: 1) effects of European contact on indigenous populations; 2) empirical estimates of minimum viable population sizes; and 3) estimates of post-contact population growth rates. We use this information to conduct population viability analysis (PVA). Our results show that all surviving populations suffered extensive mortality during, and shortly after, contact. However, most surviving populations exhibit positive growth rates within the first decade post-contact. Our findings paint a positive demographic outlook for these indigenous populations, though long-term survival remains subject to powerful externalities, including politics, economics, and the pervasive illegal exploitation of indigenous lands.

Ontogeny of modern human longitudinal body and transverse shoulder proportions.

PubMed

Frelat, Mélanie A; Coquerelle, Michael; Trinkaus, Erik

2017-03-01

Whereas variation of modern human adult body size and shape has been widely studied in the context of ecogeographical clines, little is known about the differential growth patterns of transverse and longitudinal dimensions among human populations. Our study explored the ontogenetic variation of those body proportions in modern humans. We compared results from four different approaches to study cross-sectional skeletal samples of Africans (n = 43), Amerindians (n = 69) and Europeans (n = 40) from 0 to 14 years of age. Clavicle, humerus, and femur intermetaphyseal lengths, and femoral distal metaphyseal breadth, were measured. Average ontogenetic trajectories were computed in order to compare the growth patterns of the three groups. Our findings demonstrated that the three geographical groups shared similar absolute and relative patterns of change with age for the four dimensions considered. Although interpopulation differences existed in transverse to longitudinal as well as in interlimb proportions, those differences did not seem to remain constant throughout ontogeny, similar to what has been shown for intralimb proportions. Growth rates of transverse shoulder proportions differed between populations from different regions after 10 years, whereas those for longitudinal proportions were very similar. The ontogeny of transverse shoulder proportions is more complex than what is observed for bi-iliac breadth, suggesting that transverse shoulder to limb proportions are not solely influenced by ecogeographical conditions. Our analysis demonstrates that methodologies that incorporate critical dimensions of body form could shed new light on human adaptation in both paleontological and neontological contexts. © 2016 Wiley Periodicals, Inc.

Kidney function changes with aging in adults: comparison between cross-sectional and longitudinal data analyses in renal function assessment.

PubMed

Chung, Sang M; Lee, David J; Hand, Austin; Young, Philip; Vaidyanathan, Jayabharathi; Sahajwalla, Chandrahas

2015-12-01

The study evaluated whether the renal function decline rate per year with age in adults varies based on two primary statistical analyses: cross-section (CS), using one observation per subject, and longitudinal (LT), using multiple observations per subject over time. A total of 16628 records (3946 subjects; age range 30-92 years) of creatinine clearance and relevant demographic data were used. On average, four samples per subject were collected for up to 2364 days (mean: 793 days). A simple linear regression and random coefficient models were selected for CS and LT analyses, respectively. The renal function decline rates per year were 1.33 and 0.95 ml/min/year for CS and LT analyses, respectively, and were slower when the repeated individual measurements were considered. The study confirms that rates are different based on statistical analyses, and that a statistically robust longitudinal model with a proper sampling design provides reliable individual as well as population estimates of the renal function decline rates per year with age in adults. In conclusion, our findings indicated that one should be cautious in interpreting the renal function decline rate with aging information because its estimation was highly dependent on the statistical analyses. From our analyses, a population longitudinal analysis (e.g. random coefficient model) is recommended if individualization is critical, such as a dose adjustment based on renal function during a chronic therapy. Copyright © 2015 John Wiley & Sons, Ltd.

The Impact of the College Assistance Migrant Program on Migrant Student Academic Achievement in the California State University System

ERIC Educational Resources Information Center

Ramirez, Adrian D.

2012-01-01

The 7-year longitudinal study examined the College Assistance Migrant Program (CAMP) impact on migrant student achievement in the California State University system. Participants included migrant students, Latinos, and general student populations from 2002-2009. The analysis of variance and chi-square test of independence were used to explore…

Longitudinal Study of Performance of Students Entering Harper College, Years 1967-1975. Vol. IX, No. 6.

ERIC Educational Resources Information Center

Lucas, John A.

Analysis of the transcripts of 200 full-time and 200 part-time beginning traditional credit students randomly sampled from the population of students entering each fall from 1967 to 1975 at William Rainey Harper College indicated that: (1) overall student grade point average rose in direct relationship to changes in grading policy; (2) the grade…

Social and Emotional Characteristics and Early Childhood Mathematical and Literacy Giftedness: Observations From Parents and Childcare Providers Using the ECLS-B

ERIC Educational Resources Information Center

Wilson, Hope E.

2015-01-01

Research has demonstrated mixed results regarding differences in social and emotional characteristics between gifted and typical populations. The purpose of this secondary analysis of data from the Early Childhood Longitudinal Study: Birth Cohort (ECLS-B) is to investigate the affective characteristics of early mathematics and literacy ability…

Big data in multiple sclerosis: development of a web-based longitudinal study viewer in an imaging informatics-based eFolder system for complex data analysis and management

NASA Astrophysics Data System (ADS)

Ma, Kevin; Wang, Ximing; Lerner, Alex; Shiroishi, Mark; Amezcua, Lilyana; Liu, Brent

2015-03-01

In the past, we have developed and displayed a multiple sclerosis eFolder system for patient data storage, image viewing, and automatic lesion quantification results stored in DICOM-SR format. The web-based system aims to be integrated in DICOM-compliant clinical and research environments to aid clinicians in patient treatments and disease tracking. This year, we have further developed the eFolder system to handle big data analysis and data mining in today's medical imaging field. The database has been updated to allow data mining and data look-up from DICOM-SR lesion analysis contents. Longitudinal studies are tracked, and any changes in lesion volumes and brain parenchyma volumes are calculated and shown on the webbased user interface as graphical representations. Longitudinal lesion characteristic changes are compared with patients' disease history, including treatments, symptom progressions, and any other changes in the disease profile. The image viewer is updated such that imaging studies can be viewed side-by-side to allow visual comparisons. We aim to use the web-based medical imaging informatics eFolder system to demonstrate big data analysis in medical imaging, and use the analysis results to predict MS disease trends and patterns in Hispanic and Caucasian populations in our pilot study. The discovery of disease patterns among the two ethnicities is a big data analysis result that will help lead to personalized patient care and treatment planning.

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.

Spatio-Temporal Regularization for Longitudinal Registration to Subject-Specific 3d Template

PubMed Central

Guizard, Nicolas; Fonov, Vladimir S.; García-Lorenzo, Daniel; Nakamura, Kunio; Aubert-Broche, Bérengère; Collins, D. Louis

2015-01-01

Neurodegenerative diseases such as Alzheimer's disease present subtle anatomical brain changes before the appearance of clinical symptoms. Manual structure segmentation is long and tedious and although automatic methods exist, they are often performed in a cross-sectional manner where each time-point is analyzed independently. With such analysis methods, bias, error and longitudinal noise may be introduced. Noise due to MR scanners and other physiological effects may also introduce variability in the measurement. We propose to use 4D non-linear registration with spatio-temporal regularization to correct for potential longitudinal inconsistencies in the context of structure segmentation. The major contribution of this article is the use of individual template creation with spatio-temporal regularization of the deformation fields for each subject. We validate our method with different sets of real MRI data, compare it to available longitudinal methods such as FreeSurfer, SPM12, QUARC, TBM, and KNBSI, and demonstrate that spatially local temporal regularization yields more consistent rates of change of global structures resulting in better statistical power to detect significant changes over time and between populations. PMID:26301716

Semiparametric mixed-effects analysis of PK/PD models using differential equations.

PubMed

Wang, Yi; Eskridge, Kent M; Zhang, Shunpu

2008-08-01

Motivated by the use of semiparametric nonlinear mixed-effects modeling on longitudinal data, we develop a new semiparametric modeling approach to address potential structural model misspecification for population pharmacokinetic/pharmacodynamic (PK/PD) analysis. Specifically, we use a set of ordinary differential equations (ODEs) with form dx/dt = A(t)x + B(t) where B(t) is a nonparametric function that is estimated using penalized splines. The inclusion of a nonparametric function in the ODEs makes identification of structural model misspecification feasible by quantifying the model uncertainty and provides flexibility for accommodating possible structural model deficiencies. The resulting model will be implemented in a nonlinear mixed-effects modeling setup for population analysis. We illustrate the method with an application to cefamandole data and evaluate its performance through simulations.

Fractal dimension and lacunarity analysis of mammographic patterns in assessing breast cancer risk related to HRT treated population: a longitudinal and cross-sectional study

NASA Astrophysics Data System (ADS)

Karemore, Gopal; Nielsen, Mads

2009-02-01

Structural texture measures are used to address the aspect of breast cancer risk assessment in screening mammograms. The current study investigates whether texture properties characterized by local Fractal Dimension (FD) and Lacunarity contribute to asses breast cancer risk. FD represents the complexity while the Lacunarity characterize the gappiness of a fractal. Our cross-sectional case-control study includes mammograms of 50 patients diagnosed with breast cancer in the subsequent 2-4 years and 50 matched controls. The longitudinal double blind placebo controlled HRT study includes 39 placebo and 36 HRT treated volunteers for two years. ROIs with same dimension (250*150 pixels) were created behind the nipple region on these radiographs. Box counting method was used to calculate the fractal dimension (FD) and the Lacunarity. Paired t-test and Pearson correlation coefficient were calculated. It was found that there were no differences between cancer and control group for FD (P=0.8) and Lacunarity (P=0.8) in crosssectional study whereas earlier published heterogeneity examination of radiographs (BC-HER) breast cancer risk score separated groups (p=0.002). In the longitudinal study, FD decreased significantly (P<0.05) in the HRT treated population while Lacunarity remained insignificant (P=0.2). FD is negatively correlated to Lacunarity (-0.74, P<0.001), BIRADS (-0.34, P<0.001) and Percentage Density (-0.41, P<0.001). FD is invariant to the mammographic texture change from control to cancer population but marginally varying in HRT treated population. This study yields no evidence that lacunarity or FD are suitable surrogate markers of mammographic heterogeneity as they neither pick up breast cancer risk, nor show good sensitivity to HRT.

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.

Intra- and inter-population variability and evaluation of the physical development of a young generation.

PubMed

Yampolskaya, Yulia A

2005-07-01

This study is concerned with long-term anthropometric examinations of children and adolescents aged 3-17 years in Moscow (over 10,500 persons, longitudinal and cross-sectional). Population variability of physical development was analyzed by means of regional estimation tables, which were developed on the basis of a regression analysis (scale of the regression of body mass to body length within a range from M - 1sigmaR to M + 2 sigmaR) and used for individual and group diagnostics taking into account age and sex. Such an approach allowed for the determination of the dynamics of the variability of Moscow schoolchildren from decade to decade (inter-population variability) and variations due to social differences (intra-population variability).

A Longitudinal Investigation of Reading Development from Kindergarten to Grade Eight in a Spanish-Speaking Bilingual Population

ERIC Educational Resources Information Center

Grimm, Ryan P.; Solari, Emily J.; Gerber, Michael M.

2018-01-01

This longitudinal study used latent growth curve modeling to investigate English literacy development in a sample of Spanish-speaking language minority students from third through eighth grade. This study also compared the sample's literacy development to the entire population of California students using state standardized test data. Second, this…

Equalisation of alcohol participation among socioeconomic groups over time: an analysis based on the total differential approach and longitudinal data from Sweden

PubMed Central

2011-01-01

Background Health inequality and its social determinants are well-studied, but the determinants of inequality of alcohol consumption are less well-investigated. Methods The total differential approach of decomposition of changes in the concentration index of the probability of participation in alcohol consumption was applied to 8-year longitudinal data for Swedish women aged 28-76 in 1988/89. Results Alcohol consumption showed a pro-rich inequality, with income being a strong contributor. Overall participation remained fairly constant, but the inequality decreased over time as abstinence became less common among the poor and more common among the rich. This was mainly due to changes in the relative weights of certain population groups, such as a decrease in the proportional size of the oldest cohorts. Conclusions Inequality in participation in alcohol consumption is pro-rich in Sweden. This inequality has tended to decrease over time, due to changes in population composition rather than to policy intervention. PMID:21306654

MIXOR: a computer program for mixed-effects ordinal regression analysis.

PubMed

Hedeker, D; Gibbons, R D

1996-03-01

MIXOR provides maximum marginal likelihood estimates for mixed-effects ordinal probit, logistic, and complementary log-log regression models. These models can be used for analysis of dichotomous and ordinal outcomes from either a clustered or longitudinal design. For clustered data, the mixed-effects model assumes that data within clusters are dependent. The degree of dependency is jointly estimated with the usual model parameters, thus adjusting for dependence resulting from clustering of the data. Similarly, for longitudinal data, the mixed-effects approach can allow for individual-varying intercepts and slopes across time, and can estimate the degree to which these time-related effects vary in the population of individuals. MIXOR uses marginal maximum likelihood estimation, utilizing a Fisher-scoring solution. For the scoring solution, the Cholesky factor of the random-effects variance-covariance matrix is estimated, along with the effects of model covariates. Examples illustrating usage and features of MIXOR are provided.

Eating Problems and Their Risk Factors: A 7-Year Longitudinal Study of a Population Sample of Norwegian Adolescent Girls

ERIC Educational Resources Information Center

Kansi, Juliska; Wichstrom, Lars; Bergman, Lars R.

2005-01-01

The longitudinal stability of eating problems and their relationships to risk factors were investigated in a representative population sample of 623 Norwegian girls aged 13-14 followed over 7 years (3 time points). Three eating problem symptoms were measured: Restriction, Bulimia-food preoccupation, and Diet, all taken from the 12-item Eating…

Sleep Problems in Children with Autism Spectrum Problems: A Longitudinal Population-Based Study

ERIC Educational Resources Information Center

Sivertsen, Borge; Posserud, Maj-Britt; Gillberg, Christopher; Lundervold, Astri J.; Hysing, Mari

2012-01-01

This study examined the prevalence and chronicity of sleep problems in children who manifest problems believed to be typical of Autism Spectrum Disorders (ASD). Using data from a longitudinal total population study, symptoms of ASD, insomnia and potential explanatory factors were assessed at ages 7-9 and 11-13. Children were included in a group…

A Relationship between Early Language Skills and Adult Autistic-Like Traits: Evidence from a Longitudinal Population-Based Study

ERIC Educational Resources Information Center

Armstrong, Rebecca; Whitehouse, Andrew J. O.; Scott, James G.; Copland, David A.; McMahon, Katie L.; Fleming, Sophie; Arnott, Wendy

2017-01-01

The current study examined the relationship between early language ability and autistic-like traits in adulthood, utilising data from 644 participants from a longitudinal study of the general population. Language performance at 2 years was measured with the Language Development Survey (LDS), and at 20 years the participants completed the…

Long-Term Benefits of Full-Day Kindergarten: A Longitudinal Population-Based Study

ERIC Educational Resources Information Center

Brownell, M. D.; Nickel, N. C.; Chateau, D.; Martens, P. J.; Taylor, C.; Crockett, L.; Katz, A.; Sarkar, J.; Burland, E.; Goh, C. Y.

2015-01-01

In the first longitudinal, population-based study of full-day kindergarten (FDK) outcomes beyond primary school in Canada, we used linked administrative data to follow 15 kindergarten cohorts (n ranging from 112 to 736) up to grade 9. Provincial assessments conducted in grades 3, 7, and 8 and course marks and credits earned in grade 9 were…

The influence of place on weight gain during early childhood: a population-based, longitudinal study.

PubMed

Carter, Megan Ann; Dubois, Lise; Tremblay, Mark S; Taljaard, Monica

2013-04-01

The objective of this paper was to determine the influence of place factors on weight gain in a contemporary cohort of children while also adjusting for early life and individual/family social factors. Participants from the Québec Longitudinal Study of Child Development comprised the sample for analysis (n = 1,580). A mixed-effects regression analysis was conducted to determine the longitudinal relationship between these place factors and standardized BMI, from age 4 to 10 years. The average relationship with time was found to be quadratic (rate of weight gain increased over time). Neighborhood material deprivation was found to be positively related to weight gain. Social deprivation, social disorder, and living in a medium density area were inversely related, while no association was found for social cohesion. Early life factors and genetic proxies appeared to be important in explaining weight gain in this sample. This study suggests that residential environments may play a role in childhood weight change; however, pathways are likely to be complex and interacting and perhaps not as important as early life factors and genetic proxies. Further work is required to clarify these relationships.

A longitudinal examination of the interrelationship of multiple health behaviors.

PubMed

deRuiter, Wayne K; Cairney, John; Leatherdale, Scott T; Faulkner, Guy E J

2014-09-01

Evaluating the interrelationship of health behaviors could assist in the development of effective public health interventions. Furthermore, the ability to identify cognitive mediators that may influence multiple behavioral changes requires evaluation. To evaluate covariation among health behaviors, specifically alcohol consumption, leisure-time physical activity, and smoking, and examine whether mastery acts as a mediating social-cognitive mechanism that facilitates multiple health behavior change in a longitudinal analysis. In 2010, secondary data analysis was conducted on the first seven cycles of the Canadian National Population Health Survey. Data collection began in 1994-1995 and has continued biennially. At the time of this analysis, only seven cycles of data (2006-2007) were available. Parallel process growth curve models were used to analyze covariation between health behaviors and the potential mediating effects of perceived mastery. Increases in leisure-time physical activity were associated with reductions in tobacco use, whereas declines in alcohol consumption were associated with decreases in tobacco use. Covariation between alcohol consumption and leisure-time physical activity did not reach statistical significance. For the most part, mastery was unsuccessful in mediating the interrelationship of multiple behavioral changes. Health behaviors are not independent but rather interrelated. In order to optimize limited prevention resources, these results suggest that population-level intervention efforts targeting multiple modifiable behavioral risk factors may not need to occur simultaneously. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

Second- to Third-Trimester Longitudinal Growth Assessment for the Prediction of Largeness for Gestational Age and Macrosomia in an Unselected Population.

PubMed

Caradeux, Javier; Eixarch, Elisenda; Mazarico, Edurne; Basuki, Tri Rahmat; Gratacós, Eduard; Figueras, Francesc

2018-01-01

Prenatal detection of excessive growth remains inaccurate. Most strategies rely on a single cross-sectional evaluation of fetal size during the third trimester. To compare second- to third-trimester longitudinal growth assessment with cross-sectional evaluation at the third trimester in the prediction of largeness for gestational age (LGA) and macrosomia. A cohort of 2,696 unselected singleton pregnancies scanned at 21 ± 2 and 32 ± 2 weeks was created. Abdominal circumference (AC) measurements were transformed to z values according to the INTERGROWTH-21st standards. Longitudinal growth assessment was performed by calculation of z velocity and conditional growth. Both methods were compared to cross-sectional assessment at 32 ± 2 weeks. Predictive performance for LGA and macrosomia was determined by receiver operating characteristic curve analysis. A total of 188 (7%) newborns qualified for LGA and 182 (6.8%) for macrosomia. The areas under the curve (AUCs) for 32-week AC z score, AC z velocity, and conditional AC were 0.78, 0.61, and 0.55, respectively, for the prediction of LGA, and 0.75, 0.61, and 0.55, respectively, for the prediction of macrosomia. Both AUCs of AC z velocity and conditional AC were significantly lower (p < 0.001) than the AUC of cross-sectional AC z scores. In the general population, second- to third-trimester longitudinal assessment of fetal growth is inferior to third-trimester cross-sectional evaluation of size in the prediction of LGA and macrosomia. © 2017 S. Karger AG, Basel.

Approaches in methodology for population-based longitudinal study on neuroprotective model for healthy longevity (TUA) among Malaysian Older Adults.

PubMed

Shahar, Suzana; Omar, Azahadi; Vanoh, Divya; Hamid, Tengku Aizan; Mukari, Siti Zamratol Mai-Sarah; Din, Normah Che; Rajab, Nor Fadilah; Mohammed, Zainora; Ibrahim, Rahimah; Loo, Won Hui; Meramat, Asheila; Kamaruddin, Mohd Zul Amin; Bagat, Mohamad Fazdillah; Razali, Rosdinom

2016-12-01

A number of longitudinal studies on aging have been designed to determine the predictors of healthy longevity, including the neuroprotective factors, however, relatively few studies included a wide range of factors and highlighted the challenges faced during data collection. Thus, the longitudinal study on neuroprotective model for healthy longevity (LRGS TUA) has been designed to prospectively investigate the magnitude of cognitive decline and its risk factors through a comprehensive multidimensional assessment comprising of biophysical health, auditory and visual function, nutrition and dietary pattern and psychosocial aspects. At baseline, subjects were interviewed for their status on sociodemographic, health, neuropsychological test, psychosocial and dietary intake. Subjects were also measured for anthropometric and physical function and fitness. Biospecimens including blood, buccal swap, hair and toenail were collected, processed and stored. A subsample was assessed for sensory function, i.e., vision and auditory. During follow-up, at 18 and 36 months, most of the measurements, along with morbidity and mortality outcomes will be collected. The description of mild cognitive impairment, successful aging and usual aging process is presented here. A total 2322 respondents were recruited in the data analysis at baseline. Most of the respondents were categorized as experiencing usual aging (73 %), followed by successful aging (11 %) and mild cognitive impairment (16 %). The LRGS TUA study is the most comprehensive longitudinal study on aging in Malaysia, and will contribute to the understanding of the aging process and factors associated with healthy aging and mental well-being of a multiethnic population in Malaysia.

Health shocks adversely impact participation in the labour force in a working age population: a longitudinal analysis.

PubMed

Carter, Kristie N; Gunasekara, Fiona Imlach; Blakely, Tony; Richardson, Ken

2013-06-01

It is well understood that health affects labour force participation (LFP). However, much of the published research has been on older (retiring age) populations and using subjective health measures. This paper aims to assess the impact of an objective measure of 'health shock' (cancer registration or hospitalisation) on LFP in a working age population using longitudinal panel study data and fixed effect regression analyses. Seven waves of data from 2002-09 from the longitudinal Survey of Family, Income and Employment (SoFIE) were used, including working aged individuals who consented to have their survey information linked to health records (n=6,780). Fixed effect conditional logistic regression was used to model the impact of health shocks (hospitalisation or cancer registration) in the previous year on labour force participation at date of annual interview. Models were stratified by gender, age group (25-39 years, 40-54 years) and gender by age group. A health shock was associated with a significantly increased risk of subsequent non-participation in the labour force (odds ratio 1.54, 95%CI 1.30-1.82). Although interactions of age, sex and age by sex with health shock were not statistically significant, the association was largest in younger men and women. Using an objective measure of health, we have shown that a health shock adversely affects subsequent labour force participation. There are a number of policy and practice implications relating to support for working age people who have hospitalisations. © 2013 The Authors. ANZJPH © 2013 Public Health Association of Australia.

An investigation of emotion dynamics in major depressive disorder patients and healthy persons using sparse longitudinal networks.

PubMed

de Vos, Stijn; Wardenaar, Klaas J; Bos, Elisabeth H; Wit, Ernst C; Bouwmans, Mara E J; de Jonge, Peter

2017-01-01

Differences in within-person emotion dynamics may be an important source of heterogeneity in depression. To investigate these dynamics, researchers have previously combined multilevel regression analyses with network representations. However, sparse network methods, specifically developed for longitudinal network analyses, have not been applied. Therefore, this study used this approach to investigate population-level and individual-level emotion dynamics in healthy and depressed persons and compared this method with the multilevel approach. Time-series data were collected in pair-matched healthy persons and major depressive disorder (MDD) patients (n = 54). Seven positive affect (PA) and seven negative affect (NA) items were administered electronically at 90 times (30 days; thrice per day). The population-level (healthy vs. MDD) and individual-level time series were analyzed using a sparse longitudinal network model based on vector autoregression. The population-level model was also estimated with a multilevel approach. Effects of different preprocessing steps were evaluated as well. The characteristics of the longitudinal networks were investigated to gain insight into the emotion dynamics. In the population-level networks, longitudinal network connectivity was strongest in the healthy group, with nodes showing more and stronger longitudinal associations with each other. Individually estimated networks varied strongly across individuals. Individual variations in network connectivity were unrelated to baseline characteristics (depression status, neuroticism, severity). A multilevel approach applied to the same data showed higher connectivity in the MDD group, which seemed partly related to the preprocessing approach. The sparse network approach can be useful for the estimation of networks with multiple nodes, where overparameterization is an issue, and for individual-level networks. However, its current inability to model random effects makes it less useful as a population-level approach in case of large heterogeneity. Different preprocessing strategies appeared to strongly influence the results, complicating inferences about network density.

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

Factors associated with repeated refusal to participate in longitudinal population-based HIV surveillance in rural South Africa: an observational study, regression analyses

PubMed Central

Giordano, Katie; McGrath, Nuala; Snow, Rachel; Harlow, Siobán; Newell, Marie-Louise

2014-01-01

Background For many estimation purposes, individuals who repeatedly refuse to participate in longitudinal HIV surveillance pose a bigger threat to valid inferences than individuals who participate at least occasionally. We investigate the determinants of repeated refusal to consent to HIV testing in a population-based longitudinal surveillance in rural South Africa. Methods We used data from two years (2005 & 2006) of the annual HIV surveillance conducted by the Africa Centre for Health and Population Studies, linking the HIV surveillance data to demographic and socioeconomic data. The outcome for the analysis was “repeated refusal”. Demographic variables included sex, age, highest educational attainment, and place of residence. We also included a measure of wealth and the variable “ever had sex”. To compare the association of each variable with the outcome, unadjusted odds ratios and standard errors were estimated. Multivariable logistic regression was used to estimate adjusted odds ratios and their standard errors. Data were analyzed using STATA 10.0. Results Of 15,557 eligible individuals, 46% refused to test for HIV in both rounds. Males were significantly more likely than females to repeatedly refuse testing. Holding all other variables constant, individuals in the middle age groups were more likely to repeatedly refuse testing compared with younger and older age groups. The odds of repeated refusal increased with increasing level of education and relative wealth. People living in urban areas were significantly more likely to repeatedly refuse an HIV test than people living in peri-urban or rural areas. Compared to those who had ever had sex, both males and females who had not yet had sex were significantly more likely to refuse to participate. Conclusions The likelihood of repeated refusal to test for HIV in this longitudinal surveillance increases with education, wealth, urbanization, and primary sexual abstinence. Since the factors determining repeated HIV testing refusal are likely associated with HIV status, it is critical that selection effects are controlled for in the analysis of HIV surveillance data. Interventions to increase consent to HIV testing should consider targeting the relatively well educated and wealthy, people in urban areas, and individuals who have not yet sexually debuted. PMID:25621095

The influence of management and environment on local health department organizational structure and adaptation: a longitudinal network analysis.

PubMed

Keeling, Jonathan W; Pryde, Julie A; Merrill, Jacqueline A

2013-01-01

The nation's 2862 local health departments (LHDs) are the primary means for assuring public health services for all populations. The objective of this study is to assess the effect of organizational network analysis on management decisions in LHDs and to demonstrate the technique's ability to detect organizational adaptation over time. We conducted a longitudinal network analysis in a full-service LHD with 113 employees serving about 187,000 persons. Network survey data were collected from employees at 3 times: months 0, 8, and 34. At time 1 the initial analysis was presented to LHD managers as an intervention with information on evidence-based management strategies to address the findings. At times 2 and 3 interviews documented managers' decision making and events in the task environment. Response rates for the 3 network analyses were 90%, 97%, and 83%. Postintervention (time 2) results showed beneficial changes in network measures of communication and integration. Screening and case identification increased for chlamydia and for gonorrhea. Outbreak mitigation was accelerated by cross-divisional teaming. Network measurements at time 3 showed LHD adaptation to H1N1 and budget constraints with increased centralization. Task redundancy increased dramatically after National Incident Management System training. Organizational network analysis supports LHD management with empirical evidence that can be translated into strategic decisions about communication, allocation of resources, and addressing knowledge gaps. Specific population health outcomes were traced directly to management decisions based on network evidence. The technique can help managers improve how LHDs function as organizations and contribute to our understanding of public health systems.

Atlas-Guided Segmentation of Vervet Monkey Brain MRI

PubMed Central

Fedorov, Andriy; Li, Xiaoxing; Pohl, Kilian M; Bouix, Sylvain; Styner, Martin; Addicott, Merideth; Wyatt, Chris; Daunais, James B; Wells, William M; Kikinis, Ron

2011-01-01

The vervet monkey is an important nonhuman primate model that allows the study of isolated environmental factors in a controlled environment. Analysis of monkey MRI often suffers from lower quality images compared with human MRI because clinical equipment is typically used to image the smaller monkey brain and higher spatial resolution is required. This, together with the anatomical differences of the monkey brains, complicates the use of neuroimage analysis pipelines tuned for human MRI analysis. In this paper we developed an open source image analysis framework based on the tools available within the 3D Slicer software to support a biological study that investigates the effect of chronic ethanol exposure on brain morphometry in a longitudinally followed population of male vervets. We first developed a computerized atlas of vervet monkey brain MRI, which was used to encode the typical appearance of the individual brain structures in MRI and their spatial distribution. The atlas was then used as a spatial prior during automatic segmentation to process two longitudinal scans per subject. Our evaluation confirms the consistency and reliability of the automatic segmentation. The comparison of atlas construction strategies reveals that the use of a population-specific atlas leads to improved accuracy of the segmentation for subcortical brain structures. The contribution of this work is twofold. First, we describe an image processing workflow specifically tuned towards the analysis of vervet MRI that consists solely of the open source software tools. Second, we develop a digital atlas of vervet monkey brain MRIs to enable similar studies that rely on the vervet model. PMID:22253661

Change in adult self-esteem: a longitudinal assessment.

PubMed

Schafer, R B; Keith, P M

1999-09-01

This is a longitudinal investigation of self-esteem change in an adult population. The analysis addresses two limitations in earlier studies: the use of convenience samples of children and adolescents, and cross-sectional or short-duration longitudinal studies of self-esteem change. Participants are 97 randomly selected married couples interviewed at two points in time separated by 13 years. Two components of the self were measured: self-esteem and reflected appraisals (perception of others' evaluation). Contrary to previous research on self-esteem change, a significant decline was found in all components of the self for both husbands and wives. The decline in self-esteem was not a function of age, education or income. The decline was more likely to occur for high, rather than low, self-esteem participants. This finding is attributed to the demands on higher self-esteem participants to maintain or enhance self-esteem and the caution of low self-esteem participants to engage in behaviours that would threaten the self.

Methodological issues in volumetric magnetic resonance imaging of the brain in the Edinburgh High Risk Project.

PubMed

Whalley, H C; Kestelman, J N; Rimmington, J E; Kelso, A; Abukmeil, S S; Best, J J; Johnstone, E C; Lawrie, S M

1999-07-30

The Edinburgh High Risk Project is a longitudinal study of brain structure (and function) in subjects at high risk of developing schizophrenia in the next 5-10 years for genetic reasons. In this article we describe the methods of volumetric analysis of structural magnetic resonance images used in the study. We also consider potential sources of error in these methods: the validity of our image analysis techniques; inter- and intra-rater reliability; possible positional variation; and thresholding criteria used in separating brain from cerebro-spinal fluid (CSF). Investigation with a phantom test object (of similar imaging characteristics to the brain) provided evidence for the validity of our image acquisition and analysis techniques. Both inter- and intra-rater reliability were found to be good in whole brain measures but less so for smaller regions. There were no statistically significant differences in positioning across the three study groups (patients with schizophrenia, high risk subjects and normal volunteers). A new technique for thresholding MRI scans longitudinally is described (the 'rescale' method) and compared with our established method (thresholding by eye). Few differences between the two techniques were seen at 3- and 6-month follow-up. These findings demonstrate the validity and reliability of the structural MRI analysis techniques used in the Edinburgh High Risk Project, and highlight methodological issues of general concern in cross-sectional and longitudinal studies of brain structure in healthy control subjects and neuropsychiatric populations.

Characterizing Longitudinal Patterns of Physical Activity in Mid-Adulthood Using Latent Class Analysis: Results From a Prospective Cohort Study

PubMed Central

Silverwood, Richard J.; Nitsch, Dorothea; Pierce, Mary; Kuh, Diana; Mishra, Gita D.

2011-01-01

The authors aimed to describe how longitudinal patterns of physical activity during mid-adulthood (ages 31–53 years) can be characterized using latent class analysis in a population-based birth cohort study, the Medical Research Council’s 1946 National Survey of Health and Development. Three different types of physical activity—walking, cycling, and leisure-time physical activity—were analyzed separately using self-reported data collected from questionnaires between 1977 and 1999; 3,847 study members were included in the analysis for one or more types of activity. Patterns of activity differed by sex, so stratified analyses were conducted. Two walking latent classes were identified representing low (52.8% of males in the cohort, 33.5% of females) and high (47.2%, 66.5%) levels of activity. Similar low (91.4%, 82.1%) and high (8.6%, 17.9%) classes were found for cycling, while 3 classes were identified for leisure-time physical activity: “low activity” (46.2%, 48.2%), “sports and leisure activity” (31.0%, 35.3%), and “gardening and do-it-yourself activities” (22.8%, 16.5%). The classes were reasonably or very well separated, with the exception of walking in females. Latent class analysis was found to be a useful tool for characterizing longitudinal patterns of physical activity, even when the measurement instrument differs slightly across ages, which added value in comparison with observed activity at a single age. PMID:22074812

Temporal growth and spatial distribution of the fast food industry and its relationship with economic development in China - 2005-2012.

PubMed

Xue, Hong; Cheng, Xi; Zhang, Qi; Wang, Huijun; Zhang, Bing; Qu, Weidong; Wang, Youfa

2017-09-01

The fast food (FF) industry has expanded rapidly in China during the past two decades, in parallel with an increase in the prevalence of obesity. Using government-reported longitudinal data from 21 provinces and cities in China, this study examined the growth over time and the spatial distribution patterns of the FF industry as well as the key social economic factors involved. We visualized the temporal and geographic distributions of FF industry development and conducted cross-sectional and longitudinal spatial analysis to assess associations between macroeconomic conditions, population dynamics, and the growth and distributional changes of the industry. It grew faster in the southeast coastal (more economically developed) areas since 2005 than in other regions. The industry was: 1) highly correlated with Gross Domestic Product; 2) highly correlated with per capita disposable income for urban residents; 3) moderately correlated with urban population; and 4) not correlated with an increase of population size. The mean center of the FF industry shifted westward as the mean center of the GDP moved in the same direction, while the mean center of the population shifted eastward. The results suggest that the rapid FF industry expansion in China was closely associated with economic growth and that improving the food environment should be a major component in local economic development planning. Copyright © 2017 Elsevier Inc. All rights reserved.

Time Spent Walking and Risk of Diabetes in Japanese Adults: The Japan Public Health Center-Based Prospective Diabetes Study.

PubMed

Kabeya, Yusuke; Goto, Atsushi; Kato, Masayuki; Matsushita, Yumi; Takahashi, Yoshihiko; Isogawa, Akihiro; Inoue, Manami; Mizoue, Tetsuya; Tsugane, Shoichiro; Kadowaki, Takashi; Noda, Mitsuhiko

2016-01-01

The association between time spent walking and risk of diabetes was investigated in a Japanese population-based cohort. Data from the Japan Public Health Center-based Prospective Diabetes cohort were analyzed. The surveys of diabetes were performed at baseline and at the 5-year follow-up. Time spent walking per day was assessed using a self-reported questionnaire (<30 minutes, 30 minutes to <1 hour, 1 to <2 hours, or ≥2 hours). A cross-sectional analysis was performed among 26 488 adults in the baseline survey. Logistic regression was used to examine the association between time spent walking and the presence of unrecognized diabetes. We then performed a longitudinal analysis that was restricted to 11 101 non-diabetic adults who participated in both the baseline and 5-year surveys. The association between time spent walking and the incidence of diabetes during the 5 years was examined. In the cross-sectional analysis, 1058 participants had unrecognized diabetes. Those with time spent walking of <30 minutes per day had increased odds of having diabetes in relation to those with time spent walking of ≥2 hours (adjusted odds ratio [OR] 1.23; 95% CI, 1.02-1.48). In the longitudinal analysis, 612 participants developed diabetes during the 5 years of follow-up. However, a significant association between time spent walking and the incidence of diabetes was not observed. Increased risk of diabetes was implied in those with time spent walking of <30 minutes per day, although the longitudinal analysis failed to show a significant result.

History of having a macrosomic infant and the risk of diabetes: the Japan public health center-based prospective diabetes study.

PubMed

Kabeya, Yusuke; Goto, Atsushi; Kato, Masayuki; Takahashi, Yoshihiko; Matsushita, Yumi; Inoue, Manami; Mizoue, Tetsuya; Tsugane, Shoichiro; Kadowaki, Takashi; Noda, Mitsuhiko

2013-01-01

The aim of the present study was to test a hypothesis that a history of having a macrosomic infant (≥ 4000 g) is associated with the risk of diabetes. Data on the Japan Public Health Center-based Prospective diabetes cohort were analyzed, which is a population-based cohort study on diabetes. The survey of diabetes was performed at baseline and at the 5-year follow-up. A history of having a macrosomic infant was assessed using a self-administered questionnaire. A cross-sectional analysis was performed among 12,153 women who participated in the 5-year survey of the cohort. Logistic regression was used to examine the relationship between a history of having a macrosomic infant and the presence of diabetes. A longitudinal analysis was also conducted among 7,300 women without diabetes who participated in the baseline survey. Logistic regression was used to investigate the relationship between a history of having a macrosomic infant and the incidence of diabetes between the baseline survey and the 5-year survey. In the cross-sectional analysis, parous women with a positive history were more likely to have diabetes in relation to parous women without (OR = 1.44, 95% CI = 1.13-1.83). The longitudinal analysis showed a modest but non-significant increased risk of developing diabetes among women with a positive history (OR = 1.24, 95% CI = 0.80-1.94). An increased risk of diabetes was implied among women with a history of having a macrosomic infant although the longitudinal analysis showed a non-significant increased risk.

Work time control and sleep disturbances: prospective cohort study of Finnish public sector employees.

PubMed

Salo, Paula; Ala-Mursula, Leena; Rod, Naja Hulvej; Tucker, Philip; Pentti, Jaana; Kivimäki, Mika; Vahtera, Jussi

2014-07-01

Employee control over work times has been associated with favorable psychosocial and health-related outcomes, but the evidence regarding sleep quality remains inconclusive. We examined cross-sectional and prospective associations between work time control and sleep disturbances in a large working population, taking into account total hours worked. The data were from a full-panel longitudinal cohort study of Finnish public sector employees who responded to questions on work time control and sleep disturbances in years 2000-2001, 2004-2005, 2008-2009, and 2012. The analysis of cross-sectional associations was based on 129,286 person measurements from 68,089 participants (77% women) aged 17-73 years (mean 43.1). Data from 16,503 participants were used in the longitudinal analysis. Log-binomial regression analysis with the generalized estimating equations method was used. Consistently in both cross-sectional and longitudinal models, less control over work time was associated with greater sleep disturbances in the total population and among those working normal 40-hour weeks. Among participants working more than 40 hours a week, work time that was both very high (cross-sectional prevalence ratio compared to intermediate work time control [PR] 1.32, 95% confidence interval [CI] 1.05-1.65) and very low (PR 1.23, 95% CI 1.08-1.39) was associated with sleep disturbances, after adjustment for potential confounding factors. These data suggest that having few opportunities to influence the duration and positioning of work time may increase the risk of sleep disturbances among employees. For persons working long hours, very high levels of control over working times were also associated with increased risk of sleep disturbances. Salo P, Ala-Mursula L, Rod NH, Tucker P, Pentti J, Kivimäki M, Vahtera J. Work time control and sleep disturbances: prospective cohort study of Finnish public sector employees. SLEEP 2014;37(7):1217-1225.

Work Time Control and Sleep Disturbances: Prospective Cohort Study of Finnish Public Sector Employees

PubMed Central

Salo, Paula; Ala-Mursula, Leena; Rod, Naja Hulvej; Tucker, Philip; Pentti, Jaana; Kivimäki, Mika; Vahtera, Jussi

2014-01-01

Objectives: Employee control over work times has been associated with favorable psychosocial and health-related outcomes, but the evidence regarding sleep quality remains inconclusive. We examined cross-sectional and prospective associations between work time control and sleep disturbances in a large working population, taking into account total hours worked. Methods: The data were from a full-panel longitudinal cohort study of Finnish public sector employees who responded to questions on work time control and sleep disturbances in years 2000-2001, 2004-2005, 2008-2009, and 2012. The analysis of cross-sectional associations was based on 129,286 person measurements from 68,089 participants (77% women) aged 17-73 years (mean 43.1). Data from 16,503 participants were used in the longitudinal analysis. Log-binomial regression analysis with the generalized estimating equations method was used. Results: Consistently in both cross-sectional and longitudinal models, less control over work time was associated with greater sleep disturbances in the total population and among those working normal 40-hour weeks. Among participants working more than 40 hours a week, work time that was both very high (cross-sectional prevalence ratio compared to intermediate work time control [PR] 1.32, 95% confidence interval [CI] 1.05-1.65) and very low (PR 1.23, 95% CI 1.08-1.39) was associated with sleep disturbances, after adjustment for potential confounding factors. Conclusions: These data suggest that having few opportunities to influence the duration and positioning of work time may increase the risk of sleep disturbances among employees. For persons working long hours, very high levels of control over working times were also associated with increased risk of sleep disturbances. Citation: Salo P, Ala-Mursula L, Rod NH, Tucker P, Pentti J, Kivimäki M, Vahtera J. Work time control and sleep disturbances: prospective cohort study of Finnish public sector employees. SLEEP 2014;37(7):1217-1225. PMID:25061250

Risk prediction for chronic kidney disease progression using heterogeneous electronic health record data and time series analysis.

PubMed

Perotte, Adler; Ranganath, Rajesh; Hirsch, Jamie S; Blei, David; Elhadad, Noémie

2015-07-01

As adoption of electronic health records continues to increase, there is an opportunity to incorporate clinical documentation as well as laboratory values and demographics into risk prediction modeling. The authors develop a risk prediction model for chronic kidney disease (CKD) progression from stage III to stage IV that includes longitudinal data and features drawn from clinical documentation. The study cohort consisted of 2908 primary-care clinic patients who had at least three visits prior to January 1, 2013 and developed CKD stage III during their documented history. Development and validation cohorts were randomly selected from this cohort and the study datasets included longitudinal inpatient and outpatient data from these populations. Time series analysis (Kalman filter) and survival analysis (Cox proportional hazards) were combined to produce a range of risk models. These models were evaluated using concordance, a discriminatory statistic. A risk model incorporating longitudinal data on clinical documentation and laboratory test results (concordance 0.849) predicts progression from state III CKD to stage IV CKD more accurately when compared to a similar model without laboratory test results (concordance 0.733, P<.001), a model that only considers the most recent laboratory test results (concordance 0.819, P < .031) and a model based on estimated glomerular filtration rate (concordance 0.779, P < .001). A risk prediction model that takes longitudinal laboratory test results and clinical documentation into consideration can predict CKD progression from stage III to stage IV more accurately than three models that do not take all of these variables into consideration. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association.

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.

Latitude Variation for Pluto's Crater Distribution

NASA Astrophysics Data System (ADS)

Dwivedi, A. K.; Binzel, R. P.; Earle, A. M.; Singer, K. N.; Stern, A.; Olkin, C.; Weaver, H. A., Jr.; Ennico Smith, K.; Young, L. A.

2017-12-01

The crater population distribution on Pluto and Charon have been studied to infer the size distribution of objects in the Kuiper belt (Singer et al. 2017; submitted). In this talk, we will look at the variation in crater distribution with latitude. To circumvent possible bias effects in the analysis, we focus our analysis on a region having the most consistent imaging resolution afforded by the flyby geometry. The longitudinal extent of our study region is 90E to 150E, and the latitudinal extent is 0°N to 90°N. Our preliminary analysis shows crater population peaks in the latitude range 30°N to 60°N and drops off sharply toward the north pole. Here we describe how we quantify the crater distribution in this region and explore a range of processes for volatile transport over both orbital timescales and perihelion precession timescales, including million year Milankovitch cycles for obliquity oscillations.

Population Income and Longitudinal Trends in Living Kidney Donation in the United States

PubMed Central

Dong, Jianghu; Gill, John

2015-01-01

Living kidney donation is declining in the United States. We examined longitudinal trends in living donation as a function of median household income and donor relation to assess the effect of financial barriers on donation in a changing economic environment. The zip code–level median household income of all 71,882 living donors was determined by linkage to the 2000 US Census. Longitudinal changes in the rate of donation were determined in income quintiles between 1999 and 2004, when donations were increasing, and between 2005 and 2010, when donations were declining. Rates were adjusted for population differences in age, sex, race, and ESRD rate using multilevel linear regression models. Between 1999 and 2004, the rate of growth in living donation per million population was directly related to income, increasing progressively from the lowest to highest income quintile, with annualized changes of 0.55 (95% confidence interval [95% CI], 0.14 to 1.05) for Q1 and 1.77 (95% CI, 0.66 to 2.77) for Q5 (P<0.05). Between 2005 and 2010, donation declined in Q1, Q2, and Q3; was stable in Q4; and continued to grow in Q5. Longitudinal changes varied by donor relationship, and the association of income with longitudinal changes also varied by donor relationship. In conclusion, changes in living donation in the past decade varied by median household income, resulting in increased disparities in donation between low- and high-income populations. These findings may inform public policies to support living donation during periods of economic volatility. PMID:25035519

"Old Age and Loneliness: Cross-Sectional and Longitudinal Analyses in the Tampere Longitudinal Study on Aging"

ERIC Educational Resources Information Center

Jylha, Marja

2004-01-01

The purpose of this study was to examine whether older age is associated with increasing loneliness in people aged 60 and over. Data came from TamELSA, a population-based prospective longitudinal study in Tampere, Finland. The followup time was 20 years. Loneliness was measured by a single question--"Do you feel lonely?"--with the…

What Alumni Value from New Product Development Education: A Longitudinal Study

ERIC Educational Resources Information Center

Cobb, Corie L.; Hey, Jonathan; Agogino, Alice M.; Beckman, Sara L.; Kim, Sohyeong

2016-01-01

We present a longitudinal study of what graduates take away from a cross-disciplinary graduate-level New Product Development (NPD) course at UC Berkeley over a 15-year period from 1996-2010. We designed and deployed a longitudinal survey and interviewed a segment of our NPD alumni population to better understand how well our course prepared these…

Longitudinal analysis of relationships between social support and general health in an Australian population cohort of young women.

PubMed

Holden, Libby; Lee, Christina; Hockey, Richard; Ware, Robert S; Dobson, Annette J

2015-02-01

The influence of social support on health and quality of life has been well documented. There is less evidence on whether health status affects social support, and little is known about longitudinal relationships between social support and health in early adulthood. This study investigates these associations using both concurrent and time-lagged measures at 5 time-points over 12 years during early adulthood. A population-based cohort of 9,758 young women from the Australian Longitudinal Study on Women's Health was used. Women were aged 22-27 in 2000 and 35-39 in 2012. The General Health subscale of the SF-36 and the MOS Social Support Survey 6-item Scale were used, with scores standardised to a range of 0-100. Longitudinal tobit models were used, because both social support and general health data were left skewed, with marked ceiling effects. All models were adjusted for status of the outcome of interest at the immediately previous survey. With both concurrent and time-lagged measures, there was a statistically significant difference in mean general health scores across social support quintiles after adjusting for demographic and behavioural covariates: lower general health was associated with lower social support. In reverse, social support mean scores were also significantly different across general health quintiles in both concurrent and time-lagged fully adjusted models. Social support is significantly associated with both current and subsequent general health in early adulthood. The significance of the reverse associations indicates that the two mutually influence each other. This study highlights the importance of social support as a health-related quality of life issue.

Age, Sex, and Blood Pressure-Related Influences on Reference Values of Left Atrial Deformation and Mechanics From a Large-Scale Asian Population.

PubMed

Liao, Jo-Nan; Chao, Tze-Fan; Kuo, Jen-Yuan; Sung, Kuo-Tzu; Tsai, Jui-Peng; Lo, Chi-In; Lai, Yau-Huei; Su, Cheng-Huang; Hung, Chung-Lieh; Yeh, Hung-I; Chen, Shih-Ann

2017-10-01

Left atrial (LA) function is tightly linked to several cardiovascular diseases and confers key prognostic information. Speckle tracking-based deformation as a feasible and sensitive LA mechanical assessment has proven its clinical significance beyond volume measures; however, the reference values remain largely unknown. We studied 4042 participants undergoing annual cardiovascular survey. Among them, 2812 healthy participants (65% men; mean age, 47.4±9.9 years) were eligible for speckle tracking analysis. Peak atrial longitudinal systolic strain and strain rate (SR) at systolic (SRs), early diastolic (SRe), and late diastolic atrial contraction phases (SRa) were analyzed by dedicated software (EchoPAC, GE) and compared in terms of age, sex, and blood pressure. Overall, women demonstrated higher peak atrial longitudinal systolic strain (39.34±7.99% versus 37.95±7.96%; P<0.001) and showed age-dependent more pronounced peak atrial longitudinal systolic strain functional decay than those of men (P value for interaction, <0.05), with men showing higher SRs and SRa, although lower SRe (all P<0.001). Both increasing age and higher blood pressure were independently associated with deteriorated peak atrial longitudinal systolic strain, SRs, and SRe, although augmented LA SRa, even after accounting for baseline clinical covariates in multivariable models that incorporated LA volume, NT-proBNP (N-terminal pro-B-type natriuretic peptide), or left ventricular E/e' (all P<0.001). Our findings suggest LA mechanical functional decays in association with increasing age and higher blood pressure, which seem to be compensated for by augmentation of atrial pump function. We have also provided age- and sex-stratified reference values for strain and SR based on a large-scale Asian population. © 2017 American Heart Association, Inc.

Parent Expectations Mediate Outcomes for Young Adults with Autism Spectrum Disorder.

PubMed

Kirby, Anne V

2016-05-01

Understanding the complex relationships among factors that may predict the outcomes of young adults with autism spectrum disorder (ASD) is of utmost importance given the increasing population undergoing and anticipating the transition to adulthood. With a sample of youth with ASD (n = 1170) from the National Longitudinal Transition Study-2, structural equation modeling techniques were used to test parent expectations as a mediator of young adult outcomes (i.e., employment, residential independence, social participation) in a longitudinal analysis. The mediation hypothesis was confirmed; family background and functional performance variables significantly predicted parent expectations which significantly predicted outcomes. These findings add context to previous studies examining the role of parent expectations on young adult outcomes and inform directions for family-centered interventions and future research.

Trends in acute psychiatric inpatient care in Massachusetts.

PubMed

Hudson, Christopher G

2004-11-01

This report presents the preliminary results of a longitudinal study of acute psychiatric hospitalization in the Commonwealth of Massachusetts for fiscal years 1994 to 2000. The study was a secondary analysis of data obtained through the Commonwealth's mandated case-mix reporting system, covering 42 acute psychiatric facilities and 119,284 patients. Results include a 58.4 percent increase in the patient population, accompanied by declines in both length of stay and readmission rates; increases in the number of diagnoses of depression and in the number of patient deaths; and shifts to an older population increasingly supported by Medicaid and Medicare, especially managed care programs.

Changes in aerobic power of men, ages 25-70 yr

NASA Technical Reports Server (NTRS)

Jackson, A. S.; Beard, E. F.; Wier, L. T.; Ross, R. M.; Stuteville, J. E.; Blair, S. N.

1995-01-01

This study quantified and compared the cross-sectional and longitudinal influence of age, self-report physical activity (SR-PA), and body composition (%fat) on the decline of maximal aerobic power (VO2peak). The cross-sectional sample consisted of 1,499 healthy men ages 25-70 yr. The 156 men of the longitudinal sample were from the same population and examined twice, the mean time between tests was 4.1 (+/- 1.2) yr. Peak oxygen uptake was determined by indirect calorimetry during a maximal treadmill exercise test. The zero-order correlations between VO2peak and %fat (r = -0.62) and SR-PA (r = 0.58) were significantly (P < 0.05) higher that the age correlation (r = -0.45). Linear regression defined the cross-sectional age-related decline in VO2peak at 0.46 ml.kg-1.min-1.yr-1. Multiple regression analysis (R = 0.79) showed that nearly 50% of this cross-sectional decline was due to %fat and SR-PA, adding these lifestyle variables to the multiple regression model reduced the age regression weight to -0.26 ml.kg-1.min-1.yr-1. Statistically controlling for time differences between tests, general linear models analysis showed that longitudinal changes in aerobic power were due to independent changes in %fat and SR-PA, confirming the cross-sectional results.

Relationships between eating quickly and weight gain in Japanese university students: a longitudinal study.

PubMed

Yamane, Mayu; Ekuni, Daisuke; Mizutani, Shinsuke; Kataoka, Kota; Sakumoto-Kataoka, Masami; Kawabata, Yuya; Omori, Chie; Azuma, Tetsuji; Tomofuji, Takaaki; Iwasaki, Yoshiaki; Morita, Manabu

2014-10-01

Many cross-sectional studies have reported a relationship between overweight/obesity and eating quickly, but there have been few longitudinal studies to address this relationship in younger populations. The purpose of this prospective longitudinal study was to investigate whether eating quickly was related to being overweight in Japanese university students. Of 1,396 students who underwent a general examination and completed questionnaires at the start of university and before graduation, 1,314 students (676 male and 638 female) of normal body composition [body mass index (BMI) < 25 kg m(-2) ] at baseline were included in the analysis. The questionnaires included speed of eating and other lifestyle factors. After a 3-year follow-up, the students whose BMIs were ≥ 25 kg m(-2) were defined as overweight. In this study, 38 participants (2.9%) became overweight. In the logistic regression analysis, the risk of being overweight was increased in males [adjusted odds ratio (OR): 2.77; 95% confidence interval (CI): 1.33-5.79; P < 0.01] and in those who ate quickly at baseline (OR: 4.40; 95% CI: 2.22-8.75; P < 0.001). Eating quickly may predict risk of being overweight in Japanese university students. Copyright © 2014 The Obesity Society.

A longitudinal analysis of peer-delivered permanent supportive housing: Impact of housing on mental and overall health in an ethnically diverse population.

PubMed

Crisanti, Annette S; Duran, Danielle; Greene, R Neil; Reno, Jessica; Luna-Anderson, Carol; Altschul, Deborah B

2017-05-01

Permanent supportive housing (PSH) is an evidence-based health intervention for persons experiencing homelessness, but the impact of individual mechanisms within this intervention on health requires further research. This study examines the longitudinal impact of the mechanism of supportive housing within a peer-delivered PSH model on overall health and mental health (as measured by psychological distress and self-report of bothersome symptoms) outcomes in an ethnically diverse population. The 237 participants in the study included persons who were homeless or at risk of homelessness and who also had been diagnosed with a serious mental illness. Sixty-one percent of all participants received supportive housing. All 3 outcomes were significantly associated with quality of life indicators, recovery, and social connectedness. In addition, overall health was significantly associated with employment, age, and psychological distress. Psychological distress was associated with gender, type of housing, and history of violence or trauma. Experiencing bothersome symptoms was associated with drug use, history of violence or trauma, and psychological distress. Longitudinal models of these 3 outcomes showed that supportive housing was significantly associated with good to excellent health 6 months after baseline (odds ratio = 3.11, 95% confidence interval [1.12, 8.66]). The models also demonstrated that the supportive housing and comparison groups experienced decreased psychological distress after baseline. The results of this study demonstrate the importance of supportive housing within the context of PSH, particularly for the overall health of participants, and the positive overall impact of PSH on mental health in a diverse population. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

A longitudinal cohort study of malaria exposure and changing serostatus in a malaria endemic area of rural Tanzania.

PubMed

Simmons, Ryan A; Mboera, Leonard; Miranda, Marie Lynn; Morris, Alison; Stresman, Gillian; Turner, Elizabeth L; Kramer, Randall; Drakeley, Chris; O'Meara, Wendy P

2017-08-02

Measurements of anti-malarial antibodies are increasingly used as a proxy of transmission intensity. Most serological surveys are based on the use of cross-sectional data that, when age-stratified, approximates historical patterns of transmission within a population. Comparatively few studies leverage longitudinal data to explicitly relate individual infection events with subsequent antibody responses. The occurrence of seroconversion and seroreversion events for two Plasmodium falciparum asexual stage antigens (MSP-1 and AMA-1) was examined using three annual measurements of 691 individuals from a cohort of individuals in a malaria-endemic area of rural east-central Tanzania. Mixed-effect logistic regression models were employed to determine factors associated with changes in serostatus over time. While the expected population-level relationship between seroprevalence and disease incidence was observed, on an individual level the relationship between individual infections and the antibody response was complex. MSP-1 antibody responses were more dynamic in response to the occurrence and resolution of infection events than AMA-1, while the latter was more correlated with consecutive infections. The MSP-1 antibody response to an observed infection seemed to decay faster over time than the corresponding AMA-1 response. Surprisingly, there was no evidence of an age effect on the occurrence of a conversion or reversion event. While the population-level results concur with previously published sero-epidemiological surveys, the individual-level results highlight the more complex relationship between detected infections and antibody dynamics than can be analysed using cross-sectional data. The longitudinal analysis of serological data may provide a powerful tool for teasing apart the complex relationship between infection events and the corresponding immune response, thereby improving the ability to rapidly assess the success or failure of malaria control programmes.

How effective are risk assessments/measures for predicting future aggressive behaviour in adults with intellectual disabilities (ID): A systematic review and meta-analysis.

PubMed

Lofthouse, Rachael; Golding, Laura; Totsika, Vasiliki; Hastings, Richard; Lindsay, William

2017-12-01

Risk assessments assist professionals in the identification and management of risk of aggression. The present study aimed to systematically review evidence on the efficacy of assessments for managing the risk of physical aggression in adults with intellectual disabilities (ID). A literature search was conducted using the databases PsycINFO, EMBASE, MEDLINE, Web of Science, and Google Scholar. Electronic and hand searches identified 14 studies that met the inclusion criteria. Standardised mean difference effect sizes Area Under Curve (AUC) were calculated for studies. Random effects subgroup analysis was used to compare different types of risk measures (Actuarial, Structured Professional Judgment and dynamic), and prospective vs. catch-up longitudinal study designs. Overall, evidence of predictive validity was found for risk measures with ID populations: (AUC)=0.724, 95% CI [0.681, 0.768]. There was no variation in the performance of different types of risk measures, or different study design. Risk assessment measures predict the likelihood of aggression in ID population and are comparable to those in mainstream populations. Further meta-analysis is necessary when risk measures are more established in this population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Accuracy of Bioelectrical Impedance Analysis in Estimated Longitudinal Fat-Free Mass Changes in Male Army Cadets.

PubMed

Langer, Raquel D; Matias, Catarina N; Borges, Juliano H; Cirolini, Vagner X; Páscoa, Mauro A; Guerra-Júnior, Gil; Gonçalves, Ezequiel M

2018-03-26

Bioelectrical impedance analysis (BIA) is a practical and rapid method for making a longitudinal analysis of changes in body composition. However, most BIA validation studies have been performed in a clinical population and only at one moment, or point in time (cross-sectional study). The aim of this study is to investigate the accuracy of predictive equations based on BIA with regard to the changes in fat-free mass (FFM) in Brazilian male army cadets after 7 mo of military training. The values used were determined using dual-energy X-ray absorptiometry (DXA) as a reference method. The study included 310 male Brazilian Army cadets (aged 17-24 yr). FFM was measured using eight general predictive BIA equations, with one equation specifically applied to this population sample, and the values were compared with results obtained using DXA. The student's t-test, adjusted coefficient of determination (R2), standard error of estimation (SEE), Lin's approach, and the Bland-Altman test were used to determine the accuracy of the predictive BIA equations used to estimate FFM in this population and between the two moments (pre- and post-moment). The FFM measured using the nine predictive BIA equations, and determined using DXA at the post-moment, showed a significant increase when compared with the pre-moment (p < 0.05). All nine predictive BIA equations were able to detect FFM changes in the army cadets between the two moments in a very similar way to the reference method (DXA). However, only the one BIA equation specific to this population showed no significant differences in the FFM estimation between DXA at pre- and post-moment of military routine. All predictive BIA equations showed large limits of agreement using the Bland-Altman approach. The eight general predictive BIA equations used in this study were not found to be valid for analyzing the FFM changes in the Brazilian male army cadets, after a period of approximately 7 mo of military training. Although the BIA equation specific to this population is dependent on the amount of FFM, it appears to be a good alternative to DXA for assessing FFM in Brazilian male army cadets.

Tobacco price increase and smoking behaviour changes in various subgroups: a nationwide longitudinal 7-year follow-up study among a middle-aged Japanese population

PubMed Central

Fujiwara, Takeo; Shinozaki, Tomohiro

2017-01-01

Objective Few longitudinal studies have examined the effect of tobacco price increase on both cessation among smokers and relapse among quitters. Our objective was to investigate the differential impact of the tobacco price increase on the changes in smoking status in the total population and various subgroups. Methods We analysed data from a Japanese nationally representative longitudinal study of 30 773 individuals aged 50–59 years (weighted sum of discrete-time number = 215 411) with smoking information, using inverse probability weighting to account for non-response at follow-up. Generalised estimating equation models were used to calculate the odds ratios (ORs) for smoking behavioural changes (cessation among smokers and relapse among quitters), using discrete-time design. Stratified analyses were conducted according to demographic, socioeconomic and health behavioural characteristics. Results From 2005 to 2012, current smoker prevalence among the middle-aged Japanese population decreased from 30.5% to 24.3%. Of all the factors surveyed, only the tobacco price increase in 2010 (up by 37%, the highest increase during the period) was significantly associated with both cessation among smokers (OR 2.14, 95% confidence interval 1.90 to 2.41) and prevention of relapse among quitters (0.60, 0.46 to 0.77). Regarding the subgroup analysis, the tobacco price increase was associated with a significant reduction in relapse in the lowest income, recent quitters and very poor health subgroups. However, different associations were observed for cessation; a significant association between price increase and cessation was observed among all subgroups except for the heavy smoker and recently unemployed subgroups. Conclusions We confirmed that the tobacco price rise was associated with increasing cessation and decreasing relapse concurrently. Furthermore, this price rise was associated with favourable smoking changes in nearly all population subgroups; a large differential impact was not observed across the various subgroups. PMID:26880743

Retention strategies in longitudinal studies with emerging adults.

PubMed

Hanna, Kathleen M; Scott, Linda L; Schmidt, Karen K

2014-01-01

The purpose of this report was to describe retention strategies that were useful and those that were not in a longitudinal study of emerging adults. A longitudinal study examining the transition to young adulthood among emerging adults with type 1 diabetes, which had success in retention, provided the context for describing retention strategies. A challenge in longitudinally designed studies is retention of participants because the loss decreases power for statistical analysis. Given that emerging adulthood is a period of instability, retention is particularly challenging among this population. However, longitudinal studies are the best way to understand developmental changes, and it is also important to increase our knowledge of health outcomes during emerging adulthood. Retention strategies used in the study are described, including promoting a positive relationship with participants, maintaining contact with participants, having a study staff with good interpersonal skills, using incentives, conveying respect for participants, and using user-friendly data collection. Useful strategies to promote a positive relationship included sending cards and newsletters to participants, maintaining consistency of contact person, and expressing appreciation for participant's time and effort. Useful strategies for maintaining contact with participants included obtaining contact information at every data collection point, maintaining birth dates and chart numbers in tracking databases, monitoring returned mail, and using Web search engines. Other useful strategies were providing incentives to participants, employing staff with good interpersonal skills, providing participants with choices when appropriate, and using user-friendly data collection. One strategy, using contests, was not found useful. Despite the challenges of conducting longitudinally designed studies with emerging adults, multiple retention strategies can be used that are useful to retention. It is feasible to conduct longitudinal studies with emerging adults despite the challenges.

Health Information Needs and Health Seeking Behavior During the 2014-2016 Ebola Outbreak: A Twitter Content Analysis.

PubMed

Odlum, Michelle; Yoon, Sunmoo

2018-03-23

For effective public communication during major disease outbreaks like the 2014-2016 Ebola epidemic, health information needs of the population must be adequately assessed. Through content analysis of social media data, like tweets, public health information needs can be effectively assessed and in turn provide appropriate health information to address such needs. The aim of the current study was to assess health information needs about Ebola, at distinct epidemic time points, through longitudinal tracking. Natural language processing was applied to explore public response to Ebola over time from July 2014 to March 2015. A total 155,647 tweets (unique 68,736, retweet 86,911) mentioning Ebola were analyzed and visualized with infographics. Public fear, frustration, and health information seeking regarding Ebola-related global priorities were observed across time. Our longitudinal content analysis revealed that due to ongoing health information deficiencies, resulting in fear and frustration, social media was at times an impediment and not a vehicle to support health information needs. Content analysis of tweets effectively assessed Ebola information needs. Our study also demonstrates the use of Twitter as a method for capturing real-time data to assess ongoing information needs, fear, and frustration over time.

Population density and youth antisocial behavior.

PubMed

Harden, K Paige; D'Onofrio, Brian M; Van Hulle, Carol; Turkheimer, Eric; Rodgers, Joseph L; Waldman, Irwin D; Lahey, Benjamin B

2009-08-01

Theoretical models concerning how neighborhood contexts adversely influence juvenile antisocial behavior frequently focus on urban neighborhoods; however, previous studies comparing urban and rural areas on the prevalence of youth antisocial behavior have yielded mixed results. The current study uses longitudinal data on the offspring of a nationally representative sample of mothers (N = 4,886) in the US. There was no relation between density and mother-reported child conduct problems across ages 4-13 years, but youth living in areas of greater population density exhibited more youth self-reported delinquency across 10-17 years. Families often moved to counties with greater or lesser population density, but longitudinal analyses treating population density as a time-varying covariate did not support the hypothesis that living in densely populated counties influenced youth delinquency. Rather, the association between population density and delinquency appears to be due to unmeasured selection variables that differ between families who live in more or less densely populated counties.

Closing the gap: Longitudinal changes in employment for Australians with multiple sclerosis.

PubMed

Van Dijk, Pieter A; Kirk-Brown, Andrea K; Taylor, Bruce; van der Mei, Ingrid

2017-09-01

Previous studies have documented far lower employment participation rates for people with multiple sclerosis (PwMS) compared to the general population. In a large national sample of PwMS, we examined employment status, longitudinal changes in employment and the provision of modifications to work role/environment from 2010 to 2013. Employment data were collected through the Australian MS Longitudinal Study from 2010 to 2013, with 1260 people responding to all four surveys. Employment rates were compared with the Australian general population. The survey included questions on the provision of modifications to employees' work role and work environment. Employment (full- and part-time) increased from 48.8% in 2010 to 57.8% in 2013, mainly due to increases in male full-time employment. The employment gap between PwMS and the general population fell from 14.3% in 2010 to 3.5% in 2013. Male employment rates, however, remain significantly lower than the general population. The majority of PwMS who required adjustments to either their work role or environment received them. The gap in employment between PwMS and the general population has substantially reduced from 2010 to 2013, with organisations responding positively to requests for work role/environment adjustments.

Food and fitness: associations between crop yields and life-history traits in a longitudinally monitored pre-industrial human population.

PubMed

Hayward, Adam D; Holopainen, Jari; Pettay, Jenni E; Lummaa, Virpi

2012-10-22

Severe food shortage is associated with increased mortality and reduced reproductive success in contemporary and historical human populations. Studies of wild animal populations have shown that subtle variation in environmental conditions can influence patterns of mortality, fecundity and natural selection, but the fitness implications of such subtle variation on human populations are unclear. Here, we use longitudinal data on local grain production, births, marriages and mortality so as to assess the impact of crop yield variation on individual age-specific mortality and fecundity in two pre-industrial Finnish populations. Although crop yields and fitness traits showed profound year-to-year variation across the 70-year study period, associations between crop yields and mortality or fecundity were generally weak. However, post-reproductive individuals of both sexes, and individuals of lower socio-economic status experienced higher mortality when crop yields were low. This is the first longitudinal, individual-based study of the associations between environmental variation and fitness traits in pre-industrial humans, which emphasizes the importance of a portfolio of mechanisms for coping with low food availability in such populations. The results are consistent with evolutionary ecological predictions that natural selection for resilience to food shortage is likely to weaken with age and be most severe on those with the fewest resources.

[The effect of ivermectin on geohelminth frequency (i.e. as used in the onchocerciasis control program in Colombia)].

PubMed

Knudson, Angélica; Ariza, Yoseth; López, Myriam C; Fajardo, Oscar S; Reyes, Patricia; Moncada, Ligia I; Duque, Sofía; Álvarez, Carlos A; Nicholls, Rubén S

2012-08-01

Evaluating the effect of ivermectin on soil-transmitted helminthes (STH) infection frequency in a Colombian population included in the Onchocerciasis Elimination Program for the Americas (OEPA). This was an impact evaluation study which adopted a longitudinal approach using the population of Naicioná (1996) as baseline for comparison to people from the same population as controls (2008). The cross-sectional approach involved comparing the reference population of Naicioná (2008) to the population of Dos Quebradas (2008) used as controls. Fecal samples were processed by a modified Ritchie-Frick method. Ascaris lumbricoides was the most frequently found parasite in Naicioná (60/121; 49.6 %: 37.8-63.895%CI) and in Dos Quebradas (36/76; 47.4 %: 33.2-65.6 95 % CI). Ivermectin's main effect on the population aged over 5 years was a decreased risk of Trichiuris trichiura infection in both longitudinal assessment (86 % reduction: 74-93 95 % CI) and cross-sectional assessment (63 %:24-82 95 % CI). A 93 % reduction (45-99 95 % CI) in Strongyloides stercoralis frequency was found in longitudinal assessment, compared to 85 % in cross-sectional assessment (-031-99 95 % CI). Ivermectin use in the OEPA is not sufficient for STH morbidity control. Integrated programs including education and basic sanitation are required.

Improving the Rank Precision of Population Health Measures for Small Areas with Longitudinal and Joint Outcome Models

PubMed Central

Athens, Jessica K.; Remington, Patrick L.; Gangnon, Ronald E.

2015-01-01

Objectives The University of Wisconsin Population Health Institute has published the County Health Rankings since 2010. These rankings use population-based data to highlight health outcomes and the multiple determinants of these outcomes and to encourage in-depth health assessment for all United States counties. A significant methodological limitation, however, is the uncertainty of rank estimates, particularly for small counties. To address this challenge, we explore the use of longitudinal and pooled outcome data in hierarchical Bayesian models to generate county ranks with greater precision. Methods In our models we used pooled outcome data for three measure groups: (1) Poor physical and poor mental health days; (2) percent of births with low birth weight and fair or poor health prevalence; and (3) age-specific mortality rates for nine age groups. We used the fixed and random effects components of these models to generate posterior samples of rates for each measure. We also used time-series data in longitudinal random effects models for age-specific mortality. Based on the posterior samples from these models, we estimate ranks and rank quartiles for each measure, as well as the probability of a county ranking in its assigned quartile. Rank quartile probabilities for univariate, joint outcome, and/or longitudinal models were compared to assess improvements in rank precision. Results The joint outcome model for poor physical and poor mental health days resulted in improved rank precision, as did the longitudinal model for age-specific mortality rates. Rank precision for low birth weight births and fair/poor health prevalence based on the univariate and joint outcome models were equivalent. Conclusion Incorporating longitudinal or pooled outcome data may improve rank certainty, depending on characteristics of the measures selected. For measures with different determinants, joint modeling neither improved nor degraded rank precision. This approach suggests a simple way to use existing information to improve the precision of small-area measures of population health. PMID:26098858

Occupational mortality of women aged 15-59 years at death in England and Wales.

PubMed Central

Moser, K A; Goldblatt, P O

1991-01-01

STUDY OBJECTIVE--The aim was to analyse occupational mortality differences among women using follow up data from a large nationally representative sample. DESIGN--Occupational information was obtained from the 1971 census records of women in the Longitudinal Study carried out by the Office of Population Censuses and Surveys (OPCS) and related to their subsequent mortality in the period between the 1971 and 1981 censuses. SETTING--In the Longitudinal Study, census, vital statistics, and other OPCS records are linked for a 1% sample of the population of England and Wales. The women studied in this paper were drawn from the 513,071 persons in the 1971 census who were included in the Longitudinal Study and whose entries were traced at the National Health Service Central Register by 1977. PARTICIPANTS--The analysis was based on 77,081 women aged 15-59 years in the Longitudinal Study for whom occupational information was collected in the 1971 census (99% of whom were in paid employment in the week before the census). There were 1553 deaths among these women in the follow up period analysed here. MEASUREMENTS AND MAIN RESULTS--Numbers of deaths in each occupational group at census were compared to those expected on the basis of age specific death rates among all women in the study. "Professional, technical workers, and artists" had significantly low mortality while "Engineering and allied trades workers nec" had significantly high mortality. Among the latter, cancer mortality of electrical production process workers was extremely high. A number of other cause specific associations (which appear to confirm proportionate Decennial Supplement analyses) were suggested by the data; examples include high levels of mortality from ischaemic heart disease among cooks, lung cancer and respiratory disease among charwomen and cleaners, and accidents, poisonings, and violence among several groups of professional and technical workers. CONCLUSIONS--By using prospective follow up from the census, occupational differences in mortality can be identified among women in paid employment. As follow up of this study continues, numbers of deaths available for analysis will increase, allowing increasingly comprehensive analyses to be undertaken. PMID:2072070

Longitudinal study of factors affecting taste sense decline in old-old individuals.

PubMed

Ogawa, T; Uota, M; Ikebe, K; Arai, Y; Kamide, K; Gondo, Y; Masui, Y; Ishizaki, T; Inomata, C; Takeshita, H; Mihara, Y; Hatta, K; Maeda, Y

2017-01-01

The sense of taste plays a pivotal role for personal assessment of the nutritional value, safety and quality of foods. Although it is commonly recognised that taste sensitivity decreases with age, alterations in that sensitivity over time in an old-old population have not been previously reported. Furthermore, no known studies utilised comprehensive variables regarding taste changes and related factors for assessments. Here, we report novel findings from a 3-year longitudinal study model aimed to elucidate taste sensitivity decline and its related factors in old-old individuals. We utilised 621 subjects aged 79-81 years who participated in the Septuagenarians, Octogenarians, Nonagenarians Investigation with Centenarians Study for baseline assessments performed in 2011 and 2012, and then conducted follow-up assessments 3 years later in 328 of those. Assessment of general health, an oral examination and determination of taste sensitivity were performed for each. We also evaluated cognitive function using Montreal Cognitive Assessment findings, then excluded from analysis those with a score lower than 20 in order to secure the validity and reliability of the subjects' answers. Contributing variables were selected using univariate analysis, then analysed with multivariate logistic regression analysis. We found that males showed significantly greater declines in taste sensitivity for sweet and sour tastes than females. Additionally, subjects with lower cognitive scores showed a significantly greater taste decrease for salty in multivariate analysis. In conclusion, our longitudinal study revealed that gender and cognitive status are major factors affecting taste sensitivity in geriatric individuals. © 2016 John Wiley & Sons Ltd.

Income inequality and depressive symptoms in South Africa: A longitudinal analysis of the National Income Dynamics Study.

PubMed

Adjaye-Gbewonyo, Kafui; Avendano, Mauricio; Subramanian, S V; Kawachi, Ichiro

2016-11-01

Research suggests that income inequality may detrimentally affect mental health. We examined the relationship between district-level income inequality and depressive symptoms among individuals in South Africa-one of the most unequal countries in the world-using longitudinal data from Wave 1 (2008) and Wave 3 (2012) of the National Income Dynamics Study. Depressive symptoms were measured using the Center for Epidemiological Studies of Depression Short Form while district Gini coefficients were estimated from census and survey sources. Age, African population group, being single, being female, and having lower household income were independently associated with higher depressive symptoms. However, in longitudinal, fixed-effects regression models controlling for several factors, district-level Gini coefficients were not significantly associated with depressive symptoms scores. Our results do not support the hypothesis of a causal link between income inequality and depressive symptoms in the short-run. Possible explanations include the high underlying levels of inequality in all districts, or potential lags in the effect of inequality on depression. Copyright © 2016 Elsevier Ltd. All rights reserved.

Time Spent Walking and Risk of Diabetes in Japanese Adults: The Japan Public Health Center-Based Prospective Diabetes Study

PubMed Central

Kabeya, Yusuke; Goto, Atsushi; Kato, Masayuki; Matsushita, Yumi; Takahashi, Yoshihiko; Isogawa, Akihiro; Inoue, Manami; Mizoue, Tetsuya; Tsugane, Shoichiro; Kadowaki, Takashi; Noda, Mitsuhiko

2016-01-01

Background The association between time spent walking and risk of diabetes was investigated in a Japanese population-based cohort. Methods Data from the Japan Public Health Center-based Prospective Diabetes cohort were analyzed. The surveys of diabetes were performed at baseline and at the 5-year follow-up. Time spent walking per day was assessed using a self-reported questionnaire (<30 minutes, 30 minutes to <1 hour, 1 to <2 hours, or ≥2 hours). A cross-sectional analysis was performed among 26 488 adults in the baseline survey. Logistic regression was used to examine the association between time spent walking and the presence of unrecognized diabetes. We then performed a longitudinal analysis that was restricted to 11 101 non-diabetic adults who participated in both the baseline and 5-year surveys. The association between time spent walking and the incidence of diabetes during the 5 years was examined. Results In the cross-sectional analysis, 1058 participants had unrecognized diabetes. Those with time spent walking of <30 minutes per day had increased odds of having diabetes in relation to those with time spent walking of ≥2 hours (adjusted odds ratio [OR] 1.23; 95% CI, 1.02–1.48). In the longitudinal analysis, 612 participants developed diabetes during the 5 years of follow-up. However, a significant association between time spent walking and the incidence of diabetes was not observed. Conclusions Increased risk of diabetes was implied in those with time spent walking of <30 minutes per day, although the longitudinal analysis failed to show a significant result. PMID:26725285

HIV populations are large and accumulate high genetic diversity in a nonlinear fashion.

PubMed

Maldarelli, Frank; Kearney, Mary; Palmer, Sarah; Stephens, Robert; Mican, JoAnn; Polis, Michael A; Davey, Richard T; Kovacs, Joseph; Shao, Wei; Rock-Kress, Diane; Metcalf, Julia A; Rehm, Catherine; Greer, Sarah E; Lucey, Daniel L; Danley, Kristen; Alter, Harvey; Mellors, John W; Coffin, John M

2013-09-01

HIV infection is characterized by rapid and error-prone viral replication resulting in genetically diverse virus populations. The rate of accumulation of diversity and the mechanisms involved are under intense study to provide useful information to understand immune evasion and the development of drug resistance. To characterize the development of viral diversity after infection, we carried out an in-depth analysis of single genome sequences of HIV pro-pol to assess diversity and divergence and to estimate replicating population sizes in a group of treatment-naive HIV-infected individuals sampled at single (n = 22) or multiple, longitudinal (n = 11) time points. Analysis of single genome sequences revealed nonlinear accumulation of sequence diversity during the course of infection. Diversity accumulated in recently infected individuals at rates 30-fold higher than in patients with chronic infection. Accumulation of synonymous changes accounted for most of the diversity during chronic infection. Accumulation of diversity resulted in population shifts, but the rates of change were low relative to estimated replication cycle times, consistent with relatively large population sizes. Analysis of changes in allele frequencies revealed effective population sizes that are substantially higher than previous estimates of approximately 1,000 infectious particles/infected individual. Taken together, these observations indicate that HIV populations are large, diverse, and slow to change in chronic infection and that the emergence of new mutations, including drug resistance mutations, is governed by both selection forces and drift.

Smoking and heavy drinking patterns in rural, urban and rural-to-urban migrants: the PERU MIGRANT Study.

PubMed

Taype-Rondan, Alvaro; Bernabe-Ortiz, Antonio; Alvarado, Germán F; Gilman, Robert H; Smeeth, Liam; Miranda, J Jaime

2017-02-03

Previous studies have found mixed results about cigarette and alcohol consumption patterns among rural-to-urban migrants. Moreover, there are limited longitudinal data about consumption patterns in this population. As such, this study aimed to compare the smoking and heavy drinking prevalence among rural, urban, and rural-to-urban migrants in Peru, as well as the smoking and heavy drinking incidence in a 5-year follow-up. We analyzed the PERU MIGRANT Study data from rural, urban, and rural-to-urban migrant populations in Peru. The baseline study was carried out in 2006-2007 and follow-up was performed five years later. For the baseline data analysis, the prevalence of lifetime smoking, current smokers, and heavy drinking was compared by population group using prevalence ratios (PR) and 95% confidence intervals (95% CI). For the longitudinal analysis, the incidence of smoking and heavy drinking was compared by population group with risk ratios (RR) and 95% CI. Poisson regression with robust variance was used to calculate both PRs and RRs. We analyzed data from 988 participants: 200 rural dwellers, 589 migrants, and 199 urban dwellers. Compared with migrants, lifetime smoking prevalence was higher in the urban group (PR = 2.29, 95% CI = 1.64-3.20), but lower in the rural group (PR = 0.55, 95% CI = 0.31-0.99). Compared with migrants, the urban group had a higher current smoking prevalence (PR = 2.29, 95% CI = 1.26-4.16), and a higher smoking incidence (RR = 2.75, 95% CI = 1.03-7.34). Current smoking prevalence and smoking incidence showed no significant difference between rural and migrant groups. The prevalence and incidence of heavy drinking was similar across the three population groups. Our results show a trend in lifetime smoking prevalence (urban > migrant > rural), while smoking incidence was similar between migrant and rural groups, but higher in the urban group. In addition, our results suggest that different definitions of smoking status could lead to different smoking rates and potentially different measures of association. The prevalence and incidence of heavy drinking were similar between the three population groups.

Estimating correlation between multivariate longitudinal data in the presence of heterogeneity.

PubMed

Gao, Feng; Philip Miller, J; Xiong, Chengjie; Luo, Jingqin; Beiser, Julia A; Chen, Ling; Gordon, Mae O

2017-08-17

Estimating correlation coefficients among outcomes is one of the most important analytical tasks in epidemiological and clinical research. Availability of multivariate longitudinal data presents a unique opportunity to assess joint evolution of outcomes over time. Bivariate linear mixed model (BLMM) provides a versatile tool with regard to assessing correlation. However, BLMMs often assume that all individuals are drawn from a single homogenous population where the individual trajectories are distributed smoothly around population average. Using longitudinal mean deviation (MD) and visual acuity (VA) from the Ocular Hypertension Treatment Study (OHTS), we demonstrated strategies to better understand the correlation between multivariate longitudinal data in the presence of potential heterogeneity. Conditional correlation (i.e., marginal correlation given random effects) was calculated to describe how the association between longitudinal outcomes evolved over time within specific subpopulation. The impact of heterogeneity on correlation was also assessed by simulated data. There was a significant positive correlation in both random intercepts (ρ = 0.278, 95% CI: 0.121-0.420) and random slopes (ρ = 0.579, 95% CI: 0.349-0.810) between longitudinal MD and VA, and the strength of correlation constantly increased over time. However, conditional correlation and simulation studies revealed that the correlation was induced primarily by participants with rapid deteriorating MD who only accounted for a small fraction of total samples. Conditional correlation given random effects provides a robust estimate to describe the correlation between multivariate longitudinal data in the presence of unobserved heterogeneity (NCT00000125).

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.

Evaluation of the Finnish Diabetes Risk Score to predict type 2 diabetes mellitus in a Colombian population: A longitudinal observational study.

PubMed

Gomez-Arbelaez, Diego; Alvarado-Jurado, Laura; Ayala-Castillo, Miguel; Forero-Naranjo, Leonardo; Camacho, Paul Anthony; Lopez-Jaramillo, Patricio

2015-12-10

To assess the performance of the Finnish Diabetes Risk Score (FINDRISC) questionnaire for detecting and predicting type 2 diabetes mellitus (DM2) in a Colombian population. This is a longitudinal observational study conducted in Floridablanca, Colombia. Adult subjects (age ≥ 35 years) without known diabetes, were included. A modified version of FINDRISC was completed, and the glycemia values from all the subjects were collected from the hospital's database. Firstly, a cross-sectional analysis was performed and then, the subsample of prediabetic participants was followed for diabetes incidence. A total of 772 subjects were suitable for the study. The overall prevalence of undiagnosed DM2 was 2.59%, and the incidence of DM2 among the prediabetic participants was 7.5 per 100 person-years after a total of 265257 person-years follow-up. The FINDRISC at baseline was significantly associated with undiagnosed and incident DM2. The area under receiver operating characteristics curve of the FINDRISC score for detecting undiagnosed DM2 in both men and women was 0.7477 and 0.7175, respectively; and for predicting the incidence of DM2 among prediabetics was 71.99% in men and 67.74% in women. The FINDRISC questionnaire is a useful screening tool to identify cross-sectionally unknown DM2 and to predict the incidence of DM2 among prediabetics in the Colombian population.

Unemployment and subsequent depression: A mediation analysis using the parametric G-formula.

PubMed

Bijlsma, Maarten J; Tarkiainen, Lasse; Myrskylä, Mikko; Martikainen, Pekka

2017-12-01

The effects of unemployment on depression are difficult to establish because of confounding and limited understanding of the mechanisms at the population level. In particular, due to longitudinal interdependencies between exposures, mediators and outcomes, intermediate confounding is an obstacle for mediation analyses. Using longitudinal Finnish register data on socio-economic characteristics and medication purchases, we extracted individuals who entered the labor market between ages 16 and 25 in the period 1996 to 2001 and followed them until the year 2007 (n = 42,172). With the parametric G-formula we estimated the population-averaged effect on first antidepressant purchase of a simulated intervention which set all unemployed person-years to employed. In the data, 74% of person-years were employed and 8% unemployed, the rest belonging to studying or other status. In the intervention scenario, employment rose to 85% and the hazard of first antidepressant purchase decreased by 7.6%. Of this reduction 61% was mediated, operating primarily through changes in income and household status, while mediation through other health conditions was negligible. These effects were negligible for women and particularly prominent among less educated men. By taking complex interdependencies into account in a framework of observed repeated measures data, we found that eradicating unemployment raises income levels, promotes family formation, and thereby reduces antidepressant consumption at the population-level. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Different outcomes for different health measures in immigrants: evidence from a longitudinal analysis of the National Population Health Survey (1994-2006).

PubMed

Setia, Maninder Singh; Quesnel-Vallee, Amelie; Abrahamowicz, Michal; Tousignant, Pierre; Lynch, John

2012-02-01

The response of immigrants to new societies is dynamic. There may be an initial period of happiness followed by peaks of stressful periods. These reactions along with socio-economic changes are likely to influence their health, which may start converging towards the average health of the host population. We used a longitudinal analysis to assess the differences in health outcomes (mental health and self-rated health), separately in men and women, in Canadian born and immigrants over a 12-year period (and the associated socio-economic factors). We used random effects logistic regression models for evaluation of these health outcomes in 3,081 men and 4,187 women from the National Population Health Survey (1994/95 to 2006/07). After adjusting for all the covariates, non-white immigrants were less likely to have severe psychological distress compared with the Canadian born individuals [odds ratio (OR) Men: 0.49, 95% confidence intervals (CI) 0.24-1.00, Women-OR: 0.54; 95% CI: 0.32-0.92]. Immigrant women (white and non-white) were more likely to rate their health as poor through this 12-year period than the Canadian born women (White-OR: 1.64, 95% CI: 1.17-2.64; Non-white-OR: 1.82, 95% CI: 1.01-3.28). Immigrants in the lowest income adequacy category reported higher psychological distress and poorer health than those in the highest income categories. We did not find any significant differences in the mental health and self-rated health of Canadian men and white male immigrants throughout this 12-year period. Though, non-white immigrant women were less likely to have severe psychological distress through this 12 year period, they were the ones most likely to rate their health as poor.

Prostate cancer in Germany among migrants from the Former Soviet Union

PubMed Central

Winkler, Volker; Holleczek, Bernd; Stegmaier, Christa; Becher, Heiko

2012-01-01

Background In Germany, prostate cancer is the leading cause of cancer and the third leading cause of death from cancer in males. We investigate prostate cancer in Gernmany among migrants from the Former Soviet Union (FSU) and compare them to indigenous German population with regard to prostate cancer incidence, mortality and longitudinal effects. Methods Data were obtained from two migrant cohorts residing in the federal states of North Rhine Westphalia (n=34,393) and Saarland (n=18,619). Vital status was ascertained through local population registries. Causes of death were obtained from the federal statistical office or from local health authorities. Cancer incidence of the Saarland cohort was derived from the Saarland Cancer Registry using record linkage. Results From 1990 to 2005 we observed 3360 deaths of which 28 were due to prostate cancer. In the Saarland cohort 35 men were diagnosed with prostate cancer during the respective period. Migrants had lower prostate cancer incidence (SIR 0.74 (95% CI: 0.52–1.03)) and mortality (SMR 0.57 (95% CI: 0.38–0.83)) compared to the German population. Multivariate analysis showed a strong age effect on incidence meaning young migrants (below age 60) were diagnosed significantly more often with prostate cancer compared to Germans of the same age. However, mortality did not show any effects. Discussion Lower prostate cancer mortality and incidence among migrants may reflect an ongoing situation in the FSU. Additionally, longitudinal analysis did not reveal convergence of migrant prostate cancer to German rates as expected from lifestyle driven cancer sites. Therefore, our results support the hypothesis of a genetic effect on prostate cancer risk. PMID:22229025

Cohort study of cervical ossification of posterior longitudinal ligament in a Korean populations: Demographics of prevalence, surgical treatment, and disability.

PubMed

Shin, Jaeyong; Kim, Yong Wook; Lee, Sang Gyu; Park, Eun-Cheol; Yoon, Seo Yeon

2018-03-01

To investigate the demographic characteristics of cervical ossification of posterior longitudinal ligament (OPLL) including prevalence, surgical treatment, and disability in Korean population using Korean National Health Insurance Service National Sample Cohort (NHIS-NSC) data, and to analyze association between accessibility for surgical treatment and socioeconomic factors. A population-based cohort study was conducted using stratified representative sampling from NHIS-NSC data from the year 2002 to 2013. We analyzed prevalence and distribution of cervical OPLL according to age, sex, and socioeconomic factors. Multiple logistic regression analysis was conducted to investigate associations between independent variables and the rate of surgical treatment. The overall prevalence of cervical OPLL was 190 per 100,000 people in Korea, and 11.4% of male patients and 4.0% of female patients received surgical treatment. Logistic regression analysis revealed that male patients received more surgical treatment than did female patients, also income level and residential area influence the rate of surgical treatment in females after adjustment of covariates (p< 0.05). Disability rate associated with cervical OPLL was 2.27% in male and 0.99% in female patients. In this cohort study, the prevalence of cervical OPLL was 190 per 100,000 people. Male patients received more surgery, and disability rate of male was higher than female patients. Although surgical treatment is covered by medical insurance in Korea, socioeconomic factors such as income level and residential area influence the treatment plans in females. These findings can help in the understanding of disease progression and can inform surgical treatment plans to reduce disability. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Associations of Renin-Angiotensin-Aldosterone System Genes With Blood Pressure Changes and Hypertension Incidence.

PubMed

He, William J; Li, Changwei; Rao, Dabeeru C; Hixson, James E; Huang, Jianfeng; Cao, Jie; Rice, Treva K; Shimmin, Lawrence C; Gu, Dongfeng; Kelly, Tanika N

2015-11-01

The renin-angiotensin-aldosterone system (RAAS) plays an important role in blood pressure (BP) regulation. The current study uses single-marker and gene-based analyses to examine the association between RAAS genes and longitudinal BP phenotypes in a Han Chinese population. A total of 1,768 participants from the Genetic Epidemiology Network of Salt Sensitivity (GenSalt) follow-up study were included in the current study. Twenty-seven BP measurements were taken using random-zero sphygmomanometers at baseline and 2 follow-up visits. Mixed-effect models were used to assess the additive associations of 106 single-nucleotide polymorphisms (SNPs) in 10 RAAS genes with longitudinal BP changes and hypertension incidence. Gene-based analyses were conducted using the truncated product method. Attempts were made to replicate significant findings among Asian participants of the Multi-ethnic Study of Atherosclerosis (MESA). False discovery rate procedures were used to adjust for multiple testing. During an average of 7.2 years of follow-up, average systolic and diastolic BP increased, and 32.1% (512) of participants free from hypertension at baseline developed hypertension. NR3C2 SNPs rs7694064 and rs6856803 were significantly associated with longitudinal changes in systolic BP (P interaction = 6.9×10(-5) and 8.2×10(-4), respectively). Through gene-based analysis, NR3C2 was found to be significantly associated with longitudinal systolic BP change (P value of 1.00×10(-7)), even after removal of significant markers rs7694064 and rs6856803 from the analysis. The association between NR3C2 and longitudinal systolic BP change was replicated in Asian MESA participants (P value of 1.00×10(-4)). These findings indicate that NR3C2 may play an important role in BP progression and development of hypertension. © American Journal of Hypertension, Ltd 2015. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A Comparison of Educational Differences on Physical Health, Mortality, and Healthy Life Expectancy in Japan and the United States.

PubMed

Chiu, Chi-Tsun; Hayward, Mark; Saito, Yasuhiko

2016-10-01

This study examined the educational gradient of health and mortality between two long-lived populations: Japan and the United States. This analysis is based on the Nihon University Japanese Longitudinal Study of Aging and the Health and Retirement Study to compare educational gradients in multiple aspects of population health-life expectancy with/without disability, functional limitations, or chronic diseases, using prevalence-based Sullivan life tables. Our results show that education coefficients from physical health and mortality models are similar for both Japan and American populations, and older Japanese have better mortality and health profiles. Japan's compulsory national health service system since April 1961 and living arrangements with adult children may play an important role for its superior health profile compared with that of the United States. © The Author(s) 2016.

Landscape genomics and pathway analysis to understand genetic adaptation of South African indigenous goat populations.

PubMed

Mdladla, K; Dzomba, E F; Muchadeyi, F C

2018-04-01

In Africa, extensively raised livestock populations in most smallholder farming communities are exposed to harsh and heterogeneous climatic conditions and disease pathogens that they adapt to in order to survive. Majority of these livestock species, including goats, are of non-descript and uncharacterized breeds and their response to natural selection presented by heterogeneous environments is still unresolved. This study investigated genetic diversity and its association with environmental and geographic conditions in 194 South African indigenous goats from different geographic locations genotyped on the Illumina goat SNP50K panel. Population structure analysis revealed a homogeneous genetic cluster of the Tankwa goats, restricted to the Northern Cape province. Overall, the Boer, Kalahari Red, and Savanna showed a wide geographic spread of shared genetic components, whereas the village ecotypes revealed a longitudinal distribution. The relative importance of environmental factors on genetic variation of goat populations was assessed using redundancy analysis (RDA). Climatic and geographic variables explained 22% of the total variation while climatic variables alone accounted for 17% of the diversity. Geographic variables solitarily explained 1% of the total variation. The first axis (Model I) of the RDA analysis revealed 329 outlier SNPs. Landscape genomic approaches of spatial analysis method (SAM) identified a total of 843 (1.75%) SNPs, while latent factor mixed models (LFMM) identified 714 (1.48%) SNPs significantly associated with environmental variables. Significant markers were within genes involved in biological functions potentially important for environmental adaptation. Overall, the study suggested environmental factors to have some effect in shaping the genetic variation of South African indigenous goat populations. Loci observed to be significant and under selection may be responsible for the adaption of the goat populations to local production systems.

[New design of the Health Survey of Catalonia (Spain, 2010-2014): a step forward in health planning and evaluation].

PubMed

Alcañiz-Zanón, Manuela; Mompart-Penina, Anna; Guillén-Estany, Montserrat; Medina-Bustos, Antonia; Aragay-Barbany, Josep M; Brugulat-Guiteras, Pilar; Tresserras-Gaju, Ricard

2014-01-01

This article presents the genesis of the Health Survey of Catalonia (Spain, 2010-2014) with its semiannual subsamples and explains the basic characteristics of its multistage sampling design. In comparison with previous surveys, the organizational advantages of this new statistical operation include rapid data availability and the ability to continuously monitor the population. The main benefits are timeliness in the production of indicators and the possibility of introducing new topics through the supplemental questionnaire as a function of needs. Limitations consist of the complexity of the sample design and the lack of longitudinal follow-up of the sample. Suitable sampling weights for each specific subsample are necessary for any statistical analysis of micro-data. Accuracy in the analysis of territorial disaggregation or population subgroups increases if annual samples are accumulated. Copyright © 2013 SESPAS. Published by Elsevier Espana. All rights reserved.

Multiplexed LC-MS/MS analysis of horse plasma proteins to study doping in sport.

PubMed

Barton, Chris; Beck, Paul; Kay, Richard; Teale, Phil; Roberts, Jane

2009-06-01

The development of protein biomarkers for the indirect detection of doping in horse is a potential solution to doping threats such as gene and protein doping. A method for biomarker candidate discovery in horse plasma is presented using targeted analysis of proteotypic peptides from horse proteins. These peptides were first identified in a novel list of the abundant proteins in horse plasma. To monitor these peptides, an LC-MS/MS method using multiple reaction monitoring was developed to study the quantity of 49 proteins in horse plasma in a single run. The method was optimised and validated, and then applied to a population of race-horses to study protein variance within a population. The method was finally applied to longitudinal time courses of horse plasma collected after administration of an anabolic steroid to demonstrate utility for hypothesis-driven discovery of doping biomarker candidates.

Mild thyroid hormone excess is associated with a decreased physical function in elderly men.

PubMed

Ceresini, Graziano; Ceda, Gian Paolo; Lauretani, Fulvio; Maggio, Marcello; Bandinelli, Stefania; Guralnik, Jack M; Cappola, Anne R; Usberti, Elisa; Morganti, Simonetta; Valenti, Giorgio; Ferrucci, Luigi

2011-12-01

In the adult, subclinical hyperthyroidism (Shyper) may alter skeletal muscle mass and strength. However, whether these effects are present in elderly subjects is not known. We explored the relationship between mild hyperthyroidism and physical function in a population-based sample of older persons. In a cross-sectional analysis, calf muscle cross-sectional area (CMA), handgrip strength, nerve conduction velocity (NCV), and Short Physical Performance Battery (SPPB) scores were compared between 364 euthyroid (Eut) and 28 Shyper men as well as between 502 Eut and 39 Shyper women. In a longitudinal analysis, we evaluated the relationship between baseline plasma TSH, FT3 and FT4 and the 3-year change in SPPB score in 304 men and 409 women who were euthyroid at enrolment. At the cross-sectional analysis, Shyper men, but not women, had a significantly (p = 0.02) lower SPPB score than Eut controls, although with comparable CMA, grip strength and NCV, and were more likely to have poor physical performance (odds ratio = 2.97, p < 0.05). Longitudinal analysis showed that in Eut men higher baseline FT4 was significantly (p = 0.02) predictive of a lower SPPB score at the 3-year follow-up. Even a modest thyroid hormone excess is associated with a reduced physical function in elderly men.

Health Information Needs and Health Seeking Behavior During the 2014-2016 Ebola Outbreak: A Twitter Content Analysis

PubMed Central

Odlum, Michelle; Yoon, Sunmoo

2018-01-01

Introduction: For effective public communication during major disease outbreaks like the 2014-2016 Ebola epidemic, health information needs of the population must be adequately assessed. Through content analysis of social media data, like tweets, public health information needs can be effectively assessed and in turn provide appropriate health information to address such needs. The aim of the current study was to assess health information needs about Ebola, at distinct epidemic time points, through longitudinal tracking. Methods: Natural language processing was applied to explore public response to Ebola over time from July 2014 to March 2015. A total 155,647 tweets (unique 68,736, retweet 86,911) mentioning Ebola were analyzed and visualized with infographics. Results: Public fear, frustration, and health information seeking regarding Ebola-related global priorities were observed across time. Our longitudinal content analysis revealed that due to ongoing health information deficiencies, resulting in fear and frustration, social media was at times an impediment and not a vehicle to support health information needs.  Discussion: Content analysis of tweets effectively assessed Ebola information needs. Our study also demonstrates the use of Twitter as a method for capturing real-time data to assess ongoing information needs, fear, and frustration over time.  PMID:29707416

Survey of United States Army Reserve (USAR) Troop Program Unit (TPU) soldiers 1989. Tabulation of Questionnaire Responses: Longitudinal Sample: Junior Enlisted Stayers from 1988 to 1989. 1989 Questionnaire Responses

DTIC Science & Technology

1989-09-30

AD-A237 531 1989 SURVEY OF UNITED STATES ARMY RESERVE (USAR) TROOP PROGRAM UNIT (TPU) SOLDIERS Tabulation of Questionnaire Responses: Longitudinal...Program Unit (TPU) Soldiers . The Tabulation Volumes list questionnaire items and the percent of respondents (weighted to population estimates) who have...Reserve population eligible for selection was defined by the number of personnel rec,,rds on a Dpeber 1988 SIDPERS data base; this totalled 280,265

The Change in Living Kidney Donation in Women and Men in the United States (2005-2015): A Population-Based Analysis.

PubMed

Gill, Jagbir; Joffres, Yayuk; Rose, Caren; Lesage, Julie; Landsberg, David; Kadatz, Matthew; Gill, John

2018-04-01

The factors underlying the decline in living kidney donation in the United States since 2005 must be understood to inform strategies to ensure access to this option for future patients. Population-based estimates provide a better assessment of donation activity than do trends in the number of living donor transplants. Using data from the Scientific Registry of Transplant Recipients and the United States Census, we determined longitudinal changes in living kidney donation between 2005 and 2015, focusing on the effect of sex and income. We used multilevel Poisson models to adjust for differences in age, race, the incidence of ESRD, and geographic factors (including population density, urbanization, and daily commuting). During the study period, the unadjusted rate of donation was 30.1 and 19.3 per million population in women and men, respectively, and the adjusted incidence of donation was 44% higher in women (incidence rate ratio [IRR], 1.44; 95% confidence interval [95% CI], 1.39 to 1.49). The incidence of donation was stable in women (IRR, 0.95; 95% CI, 0.84 to 1.07) but declined in men (IRR, 0.75; 95% CI, 0.68 to 0.83). Income was associated with longitudinal changes in donation in both sexes, yet donation was stable in the highest two population income quartiles in women but only in the highest income quartile in men. In both sexes, living related donations declined, irrespective of income. In conclusion, living donation declined in men but remained stable in women between 2005 and 2015, and income appeared to have a greater effect on living donation in men. Copyright © 2018 by the American Society of Nephrology.

Assessment of the effect of population and diary sampling methods on estimation of school-age children exposure to fine particles.

PubMed

Che, W W; Frey, H Christopher; Lau, Alexis K H

2014-12-01

Population and diary sampling methods are employed in exposure models to sample simulated individuals and their daily activity on each simulation day. Different sampling methods may lead to variations in estimated human exposure. In this study, two population sampling methods (stratified-random and random-random) and three diary sampling methods (random resampling, diversity and autocorrelation, and Markov-chain cluster [MCC]) are evaluated. Their impacts on estimated children's exposure to ambient fine particulate matter (PM2.5 ) are quantified via case studies for children in Wake County, NC for July 2002. The estimated mean daily average exposure is 12.9 μg/m(3) for simulated children using the stratified population sampling method, and 12.2 μg/m(3) using the random sampling method. These minor differences are caused by the random sampling among ages within census tracts. Among the three diary sampling methods, there are differences in the estimated number of individuals with multiple days of exposures exceeding a benchmark of concern of 25 μg/m(3) due to differences in how multiday longitudinal diaries are estimated. The MCC method is relatively more conservative. In case studies evaluated here, the MCC method led to 10% higher estimation of the number of individuals with repeated exposures exceeding the benchmark. The comparisons help to identify and contrast the capabilities of each method and to offer insight regarding implications of method choice. Exposure simulation results are robust to the two population sampling methods evaluated, and are sensitive to the choice of method for simulating longitudinal diaries, particularly when analyzing results for specific microenvironments or for exposures exceeding a benchmark of concern. © 2014 Society for Risk Analysis.

Does it matter what friends think, say, or do? The role of friends' smoking attitudes and behavior for Dutch adolescents' smoking behavior.

PubMed

Huisman, Chip

2014-05-01

Using stochastic actor-based models for longitudinal network analysis, this study examines the role of friends' smoking attitudes and behavior for Dutch adolescents' smoking behavior in four secondary schools (N = 875). The data were collected in two waves in two small suburban towns under second graders in 2008 to 2009 by means of a standardized questionnaire. Stochastic actor-based models for longitudinal network analysis can control for friendship selection while examining the effect of friends' attitudes and smoking behavior on the smoking behavior of a student. The findings suggest that friends tend to select each other on similar smoking behavior. Influence of friends' smoking behavior seems to play no role. In one school, an effect of friends' attitudes towards smoking on the smoking behavior is found. The implications for future research are to consider attitudes when examining the influence of friendship network on smoking behavior. The main limitation of this study lies in the limited sample, which makes generalizations to the general population difficult.

Analysis of longitudinal diffusion-weighted images in healthy and pathological aging: An ADNI study.

PubMed

Kruggel, Frithjof; Masaki, Fumitaro; Solodkin, Ana

2017-02-15

The widely used framework of voxel-based morphometry for analyzing neuroimages is extended here to model longitudinal imaging data by exchanging the linear model with a linear mixed-effects model. The new approach is employed for analyzing a large longitudinal sample of 756 diffusion-weighted images acquired in 177 subjects of the Alzheimer's Disease Neuroimaging initiative (ADNI). While sample- and group-level results from both approaches are equivalent, the mixed-effect model yields information at the single subject level. Interestingly, the neurobiological relevance of the relevant parameter at the individual level describes specific differences associated with aging. In addition, our approach highlights white matter areas that reliably discriminate between patients with Alzheimer's disease and healthy controls with a predictive power of 0.99 and include the hippocampal alveus, the para-hippocampal white matter, the white matter of the posterior cingulate, and optic tracts. In this context, notably the classifier includes a sub-population of patients with minimal cognitive impairment into the pathological domain. Our classifier offers promising features for an accessible biomarker that predicts the risk of conversion to Alzheimer's disease. Data used in preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database (adni.loni.usc.edu). As such, the investigators within the ADNI contributed to the design and implementation of ADNI and/or provided data but did not participate in analysis or writing of this report. A complete listing of ADNI investigators can be found at: http://adni.loni.usc.edu/wp-content/uploads/how to apply/ADNI Acknowledgement List.pdf. Significance statement This study assesses neuro-degenerative processes in the brain's white matter as revealed by diffusion-weighted imaging, in order to discriminate healthy from pathological aging in a large sample of elderly subjects. The analysis of time-series examinations in a linear mixed effects model allowed the discrimination of population-based aging processes from individual determinants. We demonstrate that a simple classifier based on white matter imaging data is able to predict the conversion to Alzheimer's disease with a high predictive power. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of demographics and disease progression on the relationship between glucose and HbA1c.

PubMed

Claussen, Anetta; Møller, Jonas B; Kristensen, Niels R; Klim, Søren; Kjellsson, Maria C; Ingwersen, Steen H; Karlsson, Mats O

2017-06-15

Several studies have shown that the relationship between mean plasma glucose (MPG) and glycated haemoglobin (HbA1c) may vary across populations. Especially race has previously been referred to shift the regression line that links MPG to HbA1c at steady-state (Herman & Cohen, 2012). To assess the influence of demographic and disease progression-related covariates on the intercept of the estimated linear MPG-HbA1c relationship in a longitudinal model. Longitudinal patient-level data from 16 late-phase trials in type 2 diabetes with a total of 8927 subjects was used to study covariates for the relationship between MPG and HbA1c. The analysed covariates included age group, BMI, gender, race, diabetes duration, and pre-trial treatment. Differences between trials were taken into account by estimating a trial-to-trial variability component. Participants included 47% females and 20% above 65years. 77% were Caucasian, 9% were Asian, 5% were Black and the remaining 9% were analysed together as other races. Estimates of the change in the intercept of the MPG-HbA1c relationship due to the mentioned covariates were determined using a longitudinal model. The analysis showed that pre-trial treatment with insulin had the most pronounced impact associated with a 0.34% higher HbA1c at a given MPG. However, race, diabetes duration and age group also had an impact on the MPG-HbA1c relationship. Our analysis shows that the relationship between MPG and HbA1c is relatively insensitive to covariates, but shows small variations across populations, which may be relevant to take into account when predicting HbA1c response based on MPG measurements in clinical trials. Copyright © 2017 Elsevier B.V. All rights reserved.

Left ventricular function in relation to chronic residential air pollution in a general population

PubMed Central

Yang, Wen-Yi; Zhang, Zhen-Yu; Thijs, Lutgarde; Bijnens, Esmée M; Janssen, Bram G; Vanpoucke, Charlotte; Lefebvre, Wouter; Cauwenberghs, Nicholas; Wei, Fang-Fei; Luttun, Aernout; Verhamme, Peter; Van Hecke, Etienne; Kuznetsova, Tatiana; D’hooge, Jan; Nawrot, Tim S

2017-01-01

Background In view of the increasing heart failure epidemic and awareness of the adverse impact of environmental pollution on human health, we investigated the association of left ventricular structure and function with air pollutants in a general population. Methods In 671 randomly recruited Flemish (51.7% women; mean age, 50.4 years) we echocardiographically assessed left ventricular systolic strain and strain rate and the early and late peak velocities of transmitral blood flow and mitral annular movement (2005−2009). Using subject-level data, left ventricular function was cross-sectionally correlated with residential long-term exposure to air pollutants, including black carbon, PM2.5, PM10 (particulate matter) and nitrogen dioxide (NO2), while accounting for clustering by residential address and confounders. Results Annual exposures to black carbon, PM2.5, PM10 and NO2 averaged 1.19, 13.0, 17.7, and 16.8 µg/m3. Systolic left ventricular function was worse (p ≤ 0.027) with higher black carbon, PM2.5, PM10 and NO2 with association sizes per interquartile interval increment ranging from −0.339 to −0.458% for longitudinal strain and from −0.033 to −0.049 s−1 for longitudinal strain rate. Mitral E and a′ peak velocities were lower (p ≤ 0.021) with higher black carbon, PM2.5 and PM10 with association sizes ranging from −1.727 to −1.947 cm/s and from −0.175 to −0.235 cm/s, respectively. In the geographic analysis, the systolic longitudinal strain sided with gradients in air pollution. The path analysis identified systemic inflammation as a possible mediator of associations with black carbon. Conclusions Long-term low-level air pollution is associated with subclinical impairment of left ventricular performance and might be a risk factor for heart failure. PMID:28617090

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.

Some methodological issues in the longitudinal analysis of demographic data.

PubMed

Krishinan, P

1982-12-01

Most demographic data are macro (or aggregate) in nature. Some relevant methodological issues are presented here in a time series study using aggregate data. The micro-macro distinction is relative. Time enters into the micro and macro variables in different ways. A simple micro model of rural-urban migration is given. Method 1 is to assume homogeneity in behavior. Method 2 is a Bayesian estimation. A discusssion of the results follows. Time series models of aggregate data are given. The nature of the model--predictive or explanatory--must be decided on. Explanatory models in longitudinal studies have been developed. Ways to go to the micro level from the macro are discussed. The aggregation-disaggregation problem in demography is not similar to that in econometrics. To understand small populations, separate micro level data have to be collected and analyzed and appropriate models developed. Both types of models have their uses.

Transtheoretical Model Constructs for Physical Activity Behavior are Invariant across Time among Ethnically Diverse Adults in Hawaii

PubMed Central

Nigg, Claudio R; Motl, Robert W; Horwath, Caroline; Dishman, Rod K

2012-01-01

Objectives Physical activity (PA) research applying the Transtheoretical Model (TTM) to examine group differences and/or change over time requires preliminary evidence of factorial validity and invariance. The current study examined the factorial validity and longitudinal invariance of TTM constructs recently revised for PA. Method Participants from an ethnically diverse sample in Hawaii (N=700) completed questionnaires capturing each TTM construct. Results Factorial validity was confirmed for each construct using confirmatory factor analysis with full-information maximum likelihood. Longitudinal invariance was evidenced across a shorter (3-month) and longer (6-month) time period via nested model comparisons. Conclusions The questionnaires for each validated TTM construct are provided, and can now be generalized across similar subgroups and time points. Further validation of the provided measures is suggested in additional populations and across extended time points. PMID:22778669

Coronary heart disease index based on longitudinal electrocardiography

NASA Technical Reports Server (NTRS)

Townsend, J. C.; Cronin, J. P.

1977-01-01

A coronary heart disease index was developed from longitudinal ECG (LCG) tracings to serve as a cardiac health measure in studies of working and, essentially, asymptomatic populations, such as pilots and executives. For a given subject, the index consisted of a composite score based on the presence of LCG aberrations and weighted values previously assigned to them. The index was validated by correlating it with the known presence or absence of CHD as determined by a complete physical examination, including treadmill, resting ECG, and risk factor information. The validating sample consisted of 111 subjects drawn by a stratified-random procedure from 5000 available case histories. The CHD index was found to be significantly more valid as a sole indicator of CHD than the LCG without the use of the index. The index consistently produced higher validity coefficients in identifying CHD than did treadmill testing, resting ECG, or risk factor analysis.

Generation of double giant pulses in actively Q-switched lasers

NASA Astrophysics Data System (ADS)

Korobeynikova, A. P.; Shaikin, I. A.; Shaykin, A. A.; Koryukin, I. V.; Khazanov, E. A.

2018-04-01

Generation of a second giant pulse in a longitudinal mode neighbouring to the longitudinal mode possessing minimal losses is theoretically and experimentally studied in actively Q-switched lasers. A mathematical model is suggested for explaining the giant pulse generation in a laser with multiple longitudinal modes. The model makes allowance for not only a standing, but also a running wave for each cavity mode. Results of numerical simulation and data of experiments with a Nd : YLF laser explain the effect of second giant pulse generation in a neighbouring longitudinal mode. After a giant pulse in the mode with minimal losses is generated, the threshold for the neighbouring longitudinal mode is still exceeded due to the effect of burning holes in the population inversion spatial distribution.

[Which route leads from chronic back pain to depression? A path analysis on direct and indirect effects using the cognitive mediators catastrophizing and helplessness/hopelessness in a general population sample].

PubMed

Fahland, R A; Kohlmann, T; Hasenbring, M; Feng, Y-S; Schmidt, C O

2012-12-01

Chronic pain and depression are highly comorbid; however, the longitudinal link is only partially understood. This study examined direct and indirect effects of chronic back pain on depression using path analysis in a general population sample, focussing on cognitive mediator variables. Analyses are based on 413 participants (aged 18-75 years) in a population-based postal survey on back pain who reported chronic back pain at baseline. Follow-up data were collected after 1 year. Depression was measured with the Center for Epidemiologic Studies Depression Scale (CES-D). Fear-avoidance-beliefs (FABQ), catastrophizing and helplessness/hopelessness (KRSS) were considered as cognitive mediators. Data were analyzed using path analysis. Chronic back pain had no direct effect on depression at follow-up when controlling for cognitive mediators. A mediating effect emerged for helplessness/hopelessness but not for catastrophizing or fear-avoidance beliefs. These results support the cognitive mediation hypothesis which assumes that psychological variables mediate the association between pain and depression. The importance of helplessness/hopelessness is of relevance for the treatment of patients with chronic back pain.

Longitudinal measures of perfluoroalkyl substances (PFAS) in serum of Gullah African Americans in South Carolina: 2003-2013.

PubMed

Gribble, Matthew O; Bartell, Scott M; Kannan, Kurunthachalam; Wu, Qian; Fair, Patricia A; Kamen, Diane L

2015-11-01

Charleston Harbor has elevated concentrations of PFAS in dolphins, but local human exposure data are limited. We sought to describe PFAS serum concentrations' temporal trends among Gullah African American residents of coastal South Carolina. Longitudinal measures of PFAS in blood serum from a Gullah clinical sample, without lupus, were examined using spaghetti plots and visit-to-visit change scores (e.g., differences in concentrations between visits) among the 68 participants with repeated measures available. We also modeled population-level trends among the 71 participants with any data using proportionate percentile models, accounting for clustering through robust standard errors. In a post-hoc analysis we examined heterogeneity of temporal trends by age through mixed-effects models for the log-transformed PFAS compounds. Population concentrations of PFOS dropped approximately 9 (95% CI: 8, 10) percent each year over 2003-2013. This was concordant with individual PFOS trajectories (median PFOS change score -21.7 ng/g wet weight, interquartile range of PFOS change scores: -32.8, -14.9) and reports for other populations over this time period. Several other compounds including PFOA, PFHxS, and PFuNDA also showed a population-level decrease. However, examination of individual trajectories suggested substantial heterogeneity. Post-hoc analyses indicated that PFAS trajectories were heterogeneous by age. Many PFAS compounds are decreasing in a sample of Gullah African Americans from coastal South Carolina. There may be age differences in the elimination kinetics of PFASs. The possible role of age as a modifier of PFAS serum trends merits further research. Copyright © 2015 Elsevier Inc. All rights reserved.

Cultural events - does attendance improve health? Evidence from a Polish longitudinal study.

PubMed

Węziak-Białowolska, Dorota; Białowolski, Piotr

2016-08-05

Although there is strong advocacy for uptake of both the arts and creative activities as determinants of individual health conditions, studies evaluating causal influence of attendance at cultural events on population health using individual population data on health are scarce. If available, results are often only of an associative nature. In this light, this study investigated causative impact of attendance at cultural events on self-reported and physical health in the Polish population. Four recent waves (2009, 2011, 2013 and 2015) of the biennial longitudinal Polish household panel study, Social Diagnosis, were analysed. The data, representative for the Polish population aged over 16, with respect to age, gender, classes of place of residence and NUTS 2 regions, were collected from self-report questionnaires. Causative influence of cultural attendance on population health was established using longitudinal population representative data. To account for unobserved heterogeneity of individuals and to mitigate issues caused by omitted variables, a panel data model with a fixed effects estimator was applied. The endogeneity problem (those who enjoy good health are more likely to participate in cultural activities more frequently) was circumvented by application of instrumental variables. Results confirmed positive association between cultural attendance and self-reported health. However, in contrast to the often suggested positive causative relationship, such a link was not confirmed by the study. Additionally, no evidence was found to corroborate a positive impact from cultural attendance on physical health. Both findings were substantiated by augmentation in the longitudinal perspective and causal link. We showed the relation between attendance at cultural events and self-reported health could only be confirmed as associational. Therefore, this study provided little justification to encourage use of passive cultural participation as a measure of health promotion (improvement). Our study did not confirm any identifiable benefit to physical health from passive participation in culture. Future research should investigate the causative influence of active participation in creative activities on health outcomes as, in contrast to passive attendance, it may be influential.

Analytic strategies to evaluate the association of time-varying exposures to HIV-related outcomes: Alcohol consumption as an example.

PubMed

Cook, Robert L; Kelso, Natalie E; Brumback, Babette A; Chen, Xinguang

2016-01-01

As persons with HIV are living longer, there is a growing need to investigate factors associated with chronic disease, rate of disease progression and survivorship. Many risk factors for this high-risk population change over time, such as participation in treatment, alcohol consumption and drug abuse. Longitudinal datasets are increasingly available, particularly clinical data that contain multiple observations of health exposures and outcomes over time. Several analytic options are available for assessment of longitudinal data; however, it can be challenging to choose the appropriate analytic method for specific combinations of research questions and types of data. The purpose of this review is to help researchers choose the appropriate methods to analyze longitudinal data, using alcohol consumption as an example of a time-varying exposure variable. When selecting the optimal analytic method, one must consider aspects of exposure (e.g. timing, pattern, and amount) and outcome (fixed or time-varying), while also addressing minimizing bias. In this article, we will describe several analytic approaches for longitudinal data, including developmental trajectory analysis, generalized estimating equations, and mixed effect models. For each analytic strategy, we describe appropriate situations to use the method and provide an example that demonstrates the use of the method. Clinical data related to alcohol consumption and HIV are used to illustrate these methods.

LADES: a software for constructing and analyzing longitudinal designs in biomedical research.

PubMed

Vázquez-Alcocer, Alan; Garzón-Cortes, Daniel Ladislao; Sánchez-Casas, Rosa María

2014-01-01

One of the most important steps in biomedical longitudinal studies is choosing a good experimental design that can provide high accuracy in the analysis of results with a minimum sample size. Several methods for constructing efficient longitudinal designs have been developed based on power analysis and the statistical model used for analyzing the final results. However, development of this technology is not available to practitioners through user-friendly software. In this paper we introduce LADES (Longitudinal Analysis and Design of Experiments Software) as an alternative and easy-to-use tool for conducting longitudinal analysis and constructing efficient longitudinal designs. LADES incorporates methods for creating cost-efficient longitudinal designs, unequal longitudinal designs, and simple longitudinal designs. In addition, LADES includes different methods for analyzing longitudinal data such as linear mixed models, generalized estimating equations, among others. A study of European eels is reanalyzed in order to show LADES capabilities. Three treatments contained in three aquariums with five eels each were analyzed. Data were collected from 0 up to the 12th week post treatment for all the eels (complete design). The response under evaluation is sperm volume. A linear mixed model was fitted to the results using LADES. The complete design had a power of 88.7% using 15 eels. With LADES we propose the use of an unequal design with only 14 eels and 89.5% efficiency. LADES was developed as a powerful and simple tool to promote the use of statistical methods for analyzing and creating longitudinal experiments in biomedical research.

Crash injury risk behavior in adolescent latino males: the power of friends and relational connections.

PubMed

Vaca, Federico E; Anderson, Craig L

2011-01-01

The adolescent Latino male mortality profile is an anomaly when compared to an otherwise more favorable overall U.S. Latino population mortality profile. Motor vehicle crash fatalities bear a considerable proportion of mortality burden in this vulnerable population. Friend influence and relational connection are two contextual domains that may mediate crash injury risk behavior in these adolescents. Our study goal was to assess the role of friend influence over time and relational connections associated with crash injury risk behavior (CIRB) in adolescent Latino males. Waves I and II data from the National Longitudinal Study of Adolescent Health were used. Scale of CIRB, and three relational connections; school connectedness, parent connectedness, and expectation of academic success were developed and tested. Friend nomination data were available and the index student responses were linked to friend responses. Linear regression was used to assess the relationship of relational connections and friend CIRB on index student CIRB at wave I and II. Longitudinal analysis did not show significant evidence for friend influence among adolescent Latino males on CIRB. The best predictor of CIRB at wave II for adolescent Latino males was their CIRB at wave I. Relational connections were important yet exaggerated cross-sectionally but their effect was substantially attenuated longitudinally. The lack of friend influence on CIRB for adolescent Latino males may be specific to this demographic group or characteristic of the sample studied. Prevention strategies that focus on modulating friend influence in adolescent Latino males may not yield the desired prevention effects on CIRB.

Longitudinal variability in outdoor, indoor, and personal PM 2.5 exposure in healthy non-smoking adults

NASA Astrophysics Data System (ADS)

Adgate, J. L.; Ramachandran, G.; Pratt, G. C.; Waller, L. A.; Sexton, K.

Multiple 24-h average outdoor, indoor and personal PM 2.5 measurements were made in a population of healthy non-smoking adults from the Minneapolis-St. Paul metropolitan area between April and November 1999. Personal ( P) PM 2.5 concentrations were higher than indoor ( I) concentrations, which were higher than outdoor (O) concentrations. For 28 adults with a median of 9 (range 5-11) measurements per person, the distribution of longitudinal (i.e., within-person) correlation coefficients between P and I was moderate (median r=0.45). The distribution of longitudinal correlation coefficients between I and O concentrations showed that these variables were less strongly associated (median r=0.25; 28 residences; measurement median n=10 per residence, range 7-13), and the distribution of P and O correlation coefficients (median r=0.02; 29 subjects; measurement median n=11 per subject, range 7-15) showed little statistical relation between these two variables for a majority of participants. A sensitivity analysis indicated that correlations did not increase if days with exposure to environmental tobacco smoke or occupational exposures were excluded. On average these adults spent 91% of their time indoors, and the mean of the average PM 2.5 "personal cloud" was 15.3 μg/m 3. Participants who had the largest personal cloud values tended to work outside the home and spent more time outdoors than subjects who did not work outside the home. In this population of healthy non-smoking adults, personal exposure to PM 2.5 does not correlate strongly with outdoor central site PM 2.5 concentrations.

Reliability measures of functional magnetic resonance imaging in a longitudinal evaluation of mild cognitive impairment.

PubMed

Zanto, Theodore P; Pa, Judy; Gazzaley, Adam

2014-01-01

As the aging population grows, it has become increasingly important to carefully characterize amnestic mild cognitive impairment (aMCI), a preclinical stage of Alzheimer's disease (AD). Functional magnetic resonance imaging (fMRI) is a valuable tool for monitoring disease progression in selectively vulnerable brain regions associated with AD neuropathology. However, the reliability of fMRI data in longitudinal studies of older adults with aMCI is largely unexplored. To address this, aMCI participants completed two visual working tasks, a Delayed-Recognition task and a One-Back task, on three separate scanning sessions over a three-month period. Test-retest reliability of the fMRI blood oxygen level dependent (BOLD) activity was assessed using an intraclass correlation (ICC) analysis approach. Results indicated that brain regions engaged during the task displayed greater reliability across sessions compared to regions that were not utilized by the task. During task-engagement, differential reliability scores were observed across the brain such that the frontal lobe, medial temporal lobe, and subcortical structures exhibited fair to moderate reliability (ICC=0.3-0.6), while temporal, parietal, and occipital regions exhibited moderate to good reliability (ICC=0.4-0.7). Additionally, reliability across brain regions was more stable when three fMRI sessions were used in the ICC calculation relative to two fMRI sessions. In conclusion, the fMRI BOLD signal is reliable across scanning sessions in this population and thus a useful tool for tracking longitudinal change in observational and interventional studies in aMCI. © 2013.

Longitudinal multigroup invariance analysis of the satisfaction with food-related life scale in university students.

PubMed

Schnettler, Berta; Miranda, Horacio; Miranda-Zapata, Edgardo; Salinas-Oñate, Natalia; Grunert, Klaus G; Lobos, Germán; Sepúlveda, José; Orellana, Ligia; Hueche, Clementina; Bonilla, Héctor

2017-06-01

This study examined longitudinal measurement invariance in the Satisfaction with Food-related Life (SWFL) scale using follow-up data from university students. We examined this measure of the SWFL in different groups of students, separated by various characteristics. Through non-probabilistic longitudinal sampling, 114 university students (65.8% female, mean age: 22.5) completed the SWFL questionnaire three times, over intervals of approximately one year. Confirmatory factor analysis was used to examine longitudinal measurement invariance. Two types of analysis were conducted: first, a longitudinal invariance by time, and second, a multigroup longitudinal invariance by sex, age, socio-economic status and place of residence during the study period. Results showed that the 3-item version of the SWFL exhibited strong longitudinal invariance (equal factor loadings and equal indicator intercepts). Longitudinal multigroup invariance analysis also showed that the 3-item version of the SWFL displays strong invariance by socio-economic status and place of residence during the study period over time. Nevertheless, it was only possible to demonstrate equivalence of the longitudinal factor structure among students of both sexes, and among those older and younger than 22 years. Generally, these findings suggest that the SWFL scale has satisfactory psychometric properties for longitudinal measurement invariance in university students with similar characteristics as the students that participated in this research. It is also possible to suggest that satisfaction with food-related life is associated with sex and age. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysing the relationship between family planning workers' contact and contraceptive switching in rural Bangladesh using multilevel modelling.

PubMed

Hossain, Mian B

2005-09-01

With a population of over 131 million and a fertility rate of 29.9 per 1000, population growth constitutes a primary threat to continued economic growth and development in Bangladesh. One strategy that has been used to cease further increases in fertility in Bangladesh involves using family planning outreach workers who travel throughout rural and urban areas educating women regarding contraceptive alternatives. This study uses a longitudinal database to assess the impact of family planning outreach workers' contact upon contraceptive switching and upon the risk of an unintended pregnancy. Using longitudinal data on contraceptive use from the Operations Research Project (ORP) of the International Centre for Diarrhoeal Disease Research (ICDDR,B) in Bangladesh, multiple decrement life table analysis and multilevel, discrete-time competing risk hazards models were used to estimate the cumulative probabilities of switching to an alternative form of contraceptive use after a woman engaged in a discussion with an outreach worker. After controlling for the effects of socio-demographic and economic characteristics, the analysis revealed that family planning outreach workers' contact with women significantly decreases the risk of transitioning to the non-use of contraceptives. This contact also reduces the risk of an unintended pregnancy. Family planning workers' contact with women is associated with the increased risk of a woman switching from one modern method to another modern method. The study results indicate that side-effects and other method-related reasons are the two primary reasons for contraceptive discontinuation in rural Bangladesh.

Tobacco price increase and smoking behaviour changes in various subgroups: a nationwide longitudinal 7-year follow-up study among a middle-aged Japanese population.

PubMed

Tabuchi, Takahiro; Fujiwara, Takeo; Shinozaki, Tomohiro

2017-01-01

Few longitudinal studies have examined the effect of tobacco price increase on both cessation among smokers and relapse among quitters. Our objective was to investigate the differential impact of the tobacco price increase on the changes in smoking status in the total population and various subgroups. We analysed data from a Japanese nationally representative longitudinal study of 30 773 individuals aged 50-59 years (weighted sum of discrete-time number = 215 411) with smoking information, using inverse probability weighting to account for non-response at follow-up. Generalised estimating equation models were used to calculate the odds ratios (ORs) for smoking behavioural changes (cessation among smokers and relapse among quitters), using discrete-time design. Stratified analyses were conducted according to demographic, socioeconomic and health behavioural characteristics. From 2005 to 2012, current smoker prevalence among the middle-aged Japanese population decreased from 30.5% to 24.3%. Of all the factors surveyed, only the tobacco price increase in 2010 (up by 37%, the highest increase during the period) was significantly associated with both cessation among smokers (OR 2.14, 95% confidence interval 1.90 to 2.41) and prevention of relapse among quitters (0.60, 0.46 to 0.77). Regarding the subgroup analysis, the tobacco price increase was associated with a significant reduction in relapse in the lowest income, recent quitters and very poor health subgroups. However, different associations were observed for cessation; a significant association between price increase and cessation was observed among all subgroups except for the heavy smoker and recently unemployed subgroups. We confirmed that the tobacco price rise was associated with increasing cessation and decreasing relapse concurrently. Furthermore, this price rise was associated with favourable smoking changes in nearly all population subgroups; a large differential impact was not observed across the various subgroups. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

A Primer on Longitudinal Data Analysis in Education. Technical Report #1320

ERIC Educational Resources Information Center

Nese, Joseph F. T.; Lai, Cheng-Fei; Anderson, Daniel

2013-01-01

Longitudinal data analysis in education is the study growth over time. A longitudinal study is one in which repeated observations of the same variables are recorded for the same individuals over a period of time. This type of research is known by many names (e.g., time series analysis or repeated measures design), each of which can imply subtle…

Risk factor modifications and depression incidence: a 4-year longitudinal Canadian cohort of the Montreal Catchment Area Study

PubMed Central

Meng, Xiangfei; Brunet, Alain; Turecki, Gustavo; Liu, Aihua; D'Arcy, Carl; Caron, Jean

2017-01-01

Objective Few studies have examined the effect of risk factor modifications on depression incidence. This study was to explore psychosocial risk factors for depression and quantify the effect of risk factor modifications on depression incidence in a large-scale, longitudinal population-based study. Methods Data were from the Montreal Longitudinal Catchment Area study (N=2433). Multivariate modified Poisson regression was used to estimate relative risk (RR). Population attributable fractions were also used to estimate the potential impact of risk factor modifications on depression incidence. Results The cumulative incidence rate of major depressive disorder at the 2-year follow-up was 4.8%, and 6.6% at the 4-year follow-up. Being a younger adult, female, widowed, separated or divorced, Caucasian, poor, occasional drinker, having a family history of mental health problems, having less education and living in areas with higher unemployment rates and higher proportions of visible minorities, more cultural community centres and community organisations, were consistently associated with the increased risk of incident major depressive disorder. Although only 5.1% of the disease incidence was potentially attributable to occasional drinking (vs abstainers) at the 2-year follow-up, the attribution of occasional drinking doubled at the 4-year follow-up. A 10% reduction in the prevalence of occasional drinking in this population could potentially prevent half of incident cases. Conclusions Modifiable risk factors, both individual and societal, could be the targets for public depression prevention programmes. These programmes should also be gender-specific, as different risk factors have been identified for men and women. Public health preventions at individual levels could focus on the better management of occasional drinking, as it explained around 5%~10% of incident major depressive disorders. Neighbourhood characteristics could also be the target for public prevention programmes. However, this could be very challenging. A cost-effectiveness analysis of a variety of prevention efforts is warranted. PMID:28601831

A Longitudinal Analysis of Mosquito Net Ownership and Use in an Indigenous Batwa Population after a Targeted Distribution.

PubMed

Clark, Sierra; Berrang-Ford, Lea; Lwasa, Shuaib; Namanya, Didacus; Twesigomwe, Sabastian; Kulkarni, Manisha

2016-01-01

Major efforts for malaria prevention programs have gone into scaling up ownership and use of insecticidal mosquito nets, particularly in sub-Saharan Africa where the malaria burden is high. Socioeconomic inequities in access to long lasting insecticidal nets (LLINs) are reduced with free distributions of nets. However, the relationship between social factors and retention of nets after a free distribution has been less studied, particularly using a longitudinal approach. Our research aimed to estimate the ownership and use of LLINs, and examine the determinants of LLIN retention, within an Indigenous Batwa population after a free LLIN distribution. Two LLINs were given free of charge to each Batwa household in Kanungu District, Uganda in November 2012. Surveyors collected data on LLIN ownership and use through six cross-sectional surveys pre- and post-distribution. Household retention, within household access, and individual use of LLINs were assessed over an 18-month period. Socioeconomic determinants of household retention of LLINs post-distribution were modelled longitudinally using logistic regression with random effects. Direct house-to-house distribution of free LLINs did not result in sustainable increases in the ownership and use of LLINs. Three months post-distribution, only 73% of households owned at least one LLIN and this period also saw the greatest reduction in ownership compared to other study periods. Eighteen-months post distribution, only a third of households still owned a LLIN. Self-reported age-specific use of LLINs was generally higher for children under five, declined for children aged 6-12, and was highest for older adults aged over 35. In the model, household wealth was a significant predictor of LLIN retention, controlling for time and other variables. This research highlights on-going socioeconomic inequities in access to malaria prevention measures among the Batwa in southwestern Uganda, even after free distribution of LLINs, and provides critical information to inform local malaria programs on possible intervention entry-points to increase access and use among this marginalized population.

Triglyceride and glucose (TyG) index as a predictor of incident hypertension: a 9-year longitudinal population-based study.

PubMed

Zheng, Rongjiong; Mao, Yushan

2017-09-13

Hypertension and the triglyceride and glucose index both have been associated with insulin resistance; however, the longitudinal association remains unclear. This study was designed to investigate the longitudinal association between the triglyceride and glucose index and incident hypertension among the Chinese population. We studied 4686 subjects (3177 males and 1509 females) and followed up for 9 years. The subjects were divided into four groups based on the triglyceride and glucose index. Univariate and multivariate Cox regression models were used to analyse the risk factors of hypertension. After 9 years of follow-up, 2047 subjects developed hypertension. The overall 9-year cumulative incidence of hypertension was 43.7%, ranging from 28.5% in quartile 1 to 36.9% in quartile 2, 49.2% in quartile 3 and 59.8% in quartile 4 (p for trend < 0.001). Cox regression analyses indicated that higher triglyceride and glucose index was associated with an increased risk of subsequent incident hypertension. The triglyceride and glucose index can predict the incident hypertension among the Chinese population.

The Reality of Longitudinal Data Collection: Locating Vanishing Veterans.

ERIC Educational Resources Information Center

Camara, Wayne J.; And Others

This paper investigates the utility of various procedures used to locate and interview veterans as part of a longitudinal research study being conducted for the Department of Defense. The populations are comprised of below entry aptitude standards males who entered the military during the late 1960s, and potentially ineligibles who entered between…

Predicting Posttraumatic Stress Symptoms Longitudinally in a Representative Sample of Hospitalized Injured Adolescents

ERIC Educational Resources Information Center

Zatzick, Douglas F.; Grossman, David C.; Russo, Joan; Pynoos, Robert; Berliner, Lucy; Jurkovich, Gregory; Sabin, Janice A.; Katon, Wayne; Ghesquiere, Angela; McCauley, Elizabeth; Rivara, Frederick P.

2006-01-01

Objective: Adolescents constitute a high-risk population for traumatic physical injury, yet few longitudinal investigations have assessed the development of posttraumatic stress disorder (PTSD) symptoms over time in representative samples. Method: Between July 2002 and August 2003,108 randomly selected injured adolescent patients ages 12 to 18 and…

The Role of Acculturative Stress on Mental Health Symptoms for Immigrant Adolescents: A Longitudinal Investigation

ERIC Educational Resources Information Center

Sirin, Selcuk R.; Ryce, Patrice; Gupta, Taveeshi; Rogers-Sirin, Lauren

2013-01-01

Immigrant-origin adolescents represent the fastest growing segment of youth population in the United States, and in many urban schools they represent the majority of students. In this 3-wave longitudinal study, we explored trajectories of internalizing mental health symptoms (depression, anxiety, and somatic symptoms). The participants included…

Early Indicators of Autism Spectrum Disorders at 12 and 24 Months of Age: A Prospective, Longitudinal Comparative Study

ERIC Educational Resources Information Center

Veness, Carly; Prior, Margot; Bavin, Edith; Eadie, Patricia; Cini, Eileen; Reilly, Sheena

2012-01-01

Prospective questionnaire data from a longitudinal population sample on children with autism spectrum disorders (ASD), developmental delay, specific language impairment, or typical development (TD), were collected at ages eight, 12 and 24 months, via the Communication and Symbolic Behavior Scale Developmental Profile (CSBS)--Infant Toddler…

Recruiting and Retaining an Ethnically Diverse Sample of Older Adults in a Longitudinal Intervention Study

ERIC Educational Resources Information Center

Austin-Wells, Vonnette; McDougall, Graham J.; Becker, Heather

2006-01-01

This paper describes strategies developed to recruit and retain an ethnically diverse sample in a longitudinal intervention of 246 participants in the SeniorWISE study. The ethnic and socioeconomic differences of these participants necessitated the use of different methods of effectively communicating with this population. Recruitment benefited…

Evidence for a General ADHD Factor from a Longitudinal General School Population Study

ERIC Educational Resources Information Center

Normand, Sebastien; Flora, David B.; Toplak, Maggie E.; Tannock, Rosemary

2012-01-01

Recent factor analytic studies in Attention-Deficit/Hyperactivity Disorder (ADHD) have shown that hierarchical models provide a better fit of ADHD symptoms than correlated models. A hierarchical model includes a general ADHD factor and specific factors for inattention, and hyperactivity/impulsivity. The aim of this 12-month longitudinal study was…

Criminal Victimization and Crime Risk Perception: A Multilevel Longitudinal Study

ERIC Educational Resources Information Center

Russo, Silvia; Roccato, Michele; Vieno, Alessio

2013-01-01

In a national sample of the Italian population, surveyed four times between October 2002 and January 2007 (N = 2,008), we performed a multilevel longitudinal study aimed at predicting the increase in crime risk perception as a function of three families of independent variables, respectively lying at the within individual level (direct…

Making Full Use of the Longitudinal Design of the Current Population Survey: Methods for Linking Records Across 16 Months *

PubMed Central

Drew, Julia A. Rivera; Flood, Sarah; Warren, John Robert

2015-01-01

Data from the Current Population Survey (CPS) are rarely analyzed in a way that takes advantage of the CPS’s longitudinal design. This is mainly because of the technical difficulties associated with linking CPS files across months. In this paper, we describe the method we are using to create unique identifiers for all CPS person and household records from 1989 onward. These identifiers—available along with CPS basic and supplemental data as part of the on-line Integrated Public Use Microdata Series (IPUMS)—make it dramatically easier to use CPS data for longitudinal research across any number of substantive domains. To facilitate the use of these new longitudinal IPUMS-CPS data, we also outline seven different ways that researchers may choose to link CPS person records across months, and we describe the sample sizes and sample retention rates associated with these seven designs. Finally, we discuss a number of unique methodological challenges that researchers will confront when analyzing data from linked CPS files. PMID:26113770

Relative survival: a useful tool to assess generalisability in longitudinal studies of health in older persons

PubMed Central

2011-01-01

Background Generalisability of longitudinal studies is threatened by issues such as choice of sampling frame, representativeness of the initial sample, and attrition. To determine representativeness, cohorts are often compared with the population of interest at baseline on demographic and health characteristics. This study illustrates the use of relative survival as a tool for assessing generalisability of results from a cohort of older people among whom death is a potential threat to generalisability. Methods The authors used data from the 1921-26 cohort (n = 12,416, aged 70-75 in 1996) of the Australian Longitudinal Study on Women's Health (ALSWH). Vital status was determined by linkage to the National Death Index, and expected deaths were derived using Australian life tables. Relative survival was estimated using observed survival in the cohort divided by expected survival among women of the same age and State or Territory. Results Overall, the ALSWH women showed relative survival 9.5% above the general population. Within States and Territories, the relative survival advantage varied from 6% to 23%. The interval-specific relative survival remained relatively constant over the 12 years (1996-2008) under review, indicating that the survival advantage of the cohort has not diminished over time. Conclusion This study demonstrates that relative survival can be a useful measure of generalisability in a longitudinal study of the health of the general population, particularly when participants are older. PMID:21294918

A longitudinal genetic survey identifies temporal shifts in the population structure of Dutch house sparrows

PubMed Central

Cousseau, L; Husemann, M; Foppen, R; Vangestel, C; Lens, L

2016-01-01

Dutch house sparrow (Passer domesticus) densities dropped by nearly 50% since the early 1980s, and similar collapses in population sizes have been reported across Europe. Whether, and to what extent, such relatively recent demographic changes are accompanied by concomitant shifts in the genetic population structure of this species needs further investigation. Therefore, we here explore temporal shifts in genetic diversity, genetic structure and effective sizes of seven Dutch house sparrow populations. To allow the most powerful statistical inference, historical populations were resampled at identical locations and each individual bird was genotyped using nine polymorphic microsatellites. Although the demographic history was not reflected by a reduction in genetic diversity, levels of genetic differentiation increased over time, and the original, panmictic population (inferred from the museum samples) diverged into two distinct genetic clusters. Reductions in census size were supported by a substantial reduction in effective population size, although to a smaller extent. As most studies of contemporary house sparrow populations have been unable to identify genetic signatures of recent population declines, results of this study underpin the importance of longitudinal genetic surveys to unravel cryptic genetic patterns. PMID:27273323

Job strain in relation to body mass index: pooled analysis of 160 000 adults from 13 cohort studies.

PubMed

Nyberg, S T; Heikkilä, K; Fransson, E I; Alfredsson, L; De Bacquer, D; Bjorner, J B; Bonenfant, S; Borritz, M; Burr, H; Casini, A; Clays, E; Dragano, N; Erbel, R; Geuskens, G A; Goldberg, M; Hooftman, W E; Houtman, I L; Jöckel, K-H; Kittel, F; Knutsson, A; Koskenvuo, M; Leineweber, C; Lunau, T; Madsen, I E H; Hanson, L L Magnusson; Marmot, M G; Nielsen, M L; Nordin, M; Oksanen, T; Pentti, J; Rugulies, R; Siegrist, J; Suominen, S; Vahtera, J; Virtanen, M; Westerholm, P; Westerlund, H; Zins, M; Ferrie, J E; Theorell, T; Steptoe, A; Hamer, M; Singh-Manoux, A; Batty, G D; Kivimäki, M

2012-07-01

Evidence of an association between job strain and obesity is inconsistent, mostly limited to small-scale studies, and does not distinguish between categories of underweight or obesity subclasses. To examine the association between job strain and body mass index (BMI) in a large adult population. We performed a pooled cross-sectional analysis based on individual-level data from 13 European studies resulting in a total of 161 746 participants (49% men, mean age, 43.7 years). Longitudinal analysis with a median follow-up of 4 years was possible for four cohort studies (n = 42 222). A total of 86 429 participants were of normal weight (BMI 18.5-24.9 kg m(-2) ), 2149 were underweight (BMI < 18.5 kg m(-2) ), 56 572 overweight (BMI 25.0-29.9 kg m(-2) ) and 13 523 class I (BMI 30-34.9 kg m(-2) ) and 3073 classes II/III (BMI ≥ 35 kg m(-2) ) obese. In addition, 27 010 (17%) participants reported job strain. In cross-sectional analyses, we found increased odds of job strain amongst underweight [odds ratio 1.12, 95% confidence interval (CI) 1.00-1.25], obese class I (odds ratio 1.07, 95% CI 1.02-1.12) and obese classes II/III participants (odds ratio 1.14, 95% CI 1.01-1.28) as compared with participants of normal weight. In longitudinal analysis, both weight gain and weight loss were related to the onset of job strain during follow-up. In an analysis of European data, we found both weight gain and weight loss to be associated with the onset of job strain, consistent with a 'U'-shaped cross-sectional association between job strain and BMI. These associations were relatively modest; therefore, it is unlikely that intervention to reduce job strain would be effective in combating obesity at a population level. © 2011 The Association for the Publication of the Journal of Internal Medicine.

CRITICAL EVALUATION OF MAGNETIC FIELD DETECTIONS REPORTED FOR PULSATING B-TYPE STARS IN LIGHT OF ESPaDOnS, NARVAL, AND REANALYZED FORS1/2 OBSERVATIONS

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

Shultz, M.; Wade, G. A.; Grunhut, J.

2012-05-01

Recent spectropolarimetric studies of seven slowly pulsating B (SPB) and {beta} Cep stars have suggested that photospheric magnetic fields are more common in B-type pulsators than in the general population of B stars, suggesting a significant connection between magnetic and pulsational phenomena. We present an analysis of new and previously published spectropolarimetric observations of these stars. New Stokes V observations obtained with the high-resolution ESPaDOnS and Narval instruments confirm the presence of a magnetic field in one of the stars ({epsilon} Lup), but find no evidence of magnetism in five others. A re-analysis of the published longitudinal field measurements obtainedmore » with the low-resolution FORS1/2 spectropolarimeters finds that the measurements of all stars show more scatter from zero than can be attributed to Gaussian noise, suggesting the presence of a signal and/or systematic underestimation of error bars. Re-reduction and re-measurement of the FORS1/2 spectra from the ESO archive demonstrates that small changes in reduction procedure lead to substantial changes in the inferred longitudinal field, and substantially reduces the number of field detections at the 3{sigma} level. Furthermore, we find that the published periods are not unique solutions to the time series of either the original or the revised FORS1/2 data. We conclude that the reported field detections, proposed periods, and field geometry models for {alpha} Pyx, 15 CMa, 33 Eri, and V1449 Aql are artifacts of the data analysis and reduction procedures, and that magnetic fields at the reported strength are no more common in SPB/{beta} Cep stars than in the general population of B stars.« less

Mortality among immigrants in England and Wales by major causes of death, 1971-2012: A longitudinal analysis of register-based data.

PubMed

Wallace, Matthew; Kulu, Hill

2015-12-01

Recent research has found a migrant mortality advantage among immigrants relative to the UK-born population living in England and Wales. However, while all-cause mortality is useful to show differences in mortality between immigrants and the host population, it can mask variation in mortality patterns from specific causes of death. This study analyses differences in the causes of death among immigrants living in England and Wales. We extend previous research by applying competing-risks survival analysis to study a large-scale longitudinal dataset from 1971 to 2012 to directly compare causes of death. We confirm low all-cause mortality among nearly all immigrants, except immigrants from Scotland, Northern Ireland and the Republic of Ireland (who have high mortality). In most cases, low all-cause mortality among immigrants is driven by lower mortality from chronic diseases (in nearly all cases by lower cancer mortality and in some cases by lower mortality from cardiovascular diseases (CVD)). This low all-cause mortality often coexists with low respiratory disease mortality and among non-western immigrants, coexists with high mortality from infectious diseases; however, these two causes of death contribute little to mortality among immigrants. For men, CVD is the leading cause of death (particularly among South Asians). For women, cancer is the leading cause of death (except among South Asians, for whom CVD is also the leading cause). Differences in CVD mortality over time remain constant between immigrants relative to UK-born, but immigrant cancer patterns shows signs of some convergence to the cancer mortality among the UK-born (though cancer mortality is still low among immigrants by age 80). The study provides the most up-to-date, reliable UK-based analysis of immigrant mortality. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of the Finnish Diabetes Risk Score to predict type 2 diabetes mellitus in a Colombian population: A longitudinal observational study

PubMed Central

Gomez-Arbelaez, Diego; Alvarado-Jurado, Laura; Ayala-Castillo, Miguel; Forero-Naranjo, Leonardo; Camacho, Paul Anthony; Lopez-Jaramillo, Patricio

2015-01-01

AIM: To assess the performance of the Finnish Diabetes Risk Score (FINDRISC) questionnaire for detecting and predicting type 2 diabetes mellitus (DM2) in a Colombian population. METHODS: This is a longitudinal observational study conducted in Floridablanca, Colombia. Adult subjects (age ≥ 35 years) without known diabetes, were included. A modified version of FINDRISC was completed, and the glycemia values from all the subjects were collected from the hospital’s database. Firstly, a cross-sectional analysis was performed and then, the subsample of prediabetic participants was followed for diabetes incidence. RESULTS: A total of 772 subjects were suitable for the study. The overall prevalence of undiagnosed DM2 was 2.59%, and the incidence of DM2 among the prediabetic participants was 7.5 per 100 person-years after a total of 265257 person-years follow-up. The FINDRISC at baseline was significantly associated with undiagnosed and incident DM2. The area under receiver operating characteristics curve of the FINDRISC score for detecting undiagnosed DM2 in both men and women was 0.7477 and 0.7175, respectively; and for predicting the incidence of DM2 among prediabetics was 71.99% in men and 67.74% in women. CONCLUSION: The FINDRISC questionnaire is a useful screening tool to identify cross-sectionally unknown DM2 and to predict the incidence of DM2 among prediabetics in the Colombian population. PMID:26675051

Associations between cognitive abilities and life satisfaction in the oldest-old. Results from the longitudinal population study Good Aging in Skåne

PubMed Central

Enkvist, Åsa; Ekström, Henrik; Elmståhl, Sölve

2013-01-01

Introduction Studies on the associations between cognitive abilities and life satisfaction (LS) in the oldest-old are few. The aim of this study was to explore whether abilities in six different cognitive domains could predict LS in the oldest-old 3 years later. Methods The study population consisted of 681 individuals aged 78–98 years, drawn from the longitudinal population study “Good Aging in Skåne,” which is part of a national survey (The Swedish National Study on Aging and Care). Scores on 13 cognitive tests were related to scores on Neugartens’ LS index A (LSI-A) 3 years later. The cognitive tests were added into six different cognitive domains. A multiple regression analysis was constructed for each cognitive domain separately, with scores on the LSI-A as the dependent variable. The model was adjusted stepwise for sex, age, education, functional capacity, and depressive mood. Results Significant correlations were found between digit cancellation, word recall, verbal fluency (VF) A, VF animals, VF occupations, and mental rotations at baseline, as well as LSI-A at follow-up. The domains of spatial abilities (B = 0.453, P = 0.014) and processing speed (B = 0.118, P = 0.020) remained significantly associated with LSI-A 3 years later after adjustment. Conclusion The cognitive domains of spatial abilities and processing speed predicted LS 3 years later in the oldest-old. Clinical implications are discussed. PMID:23874091

Is Child Abuse Associated with Adolescent Obesity? A Population Cohort Study.

PubMed

Hawton, Katherine; Norris, Tom; Crawley, Esther; Shield, Julian P H

Child abuse is associated with obesity in adulthood through multiple mechanisms. However, little is known about the relationship between abuse and obesity during adolescence. The aim of this study was to investigate, using a birth cohort, whether there is an association between child abuse and overweight or obesity in adolescence. This study utilizes data from the Avon Longitudinal Study of Parents and Children, a prospective cohort study based in South West England. Using data from the 4205 children with complete data at 13 and 16 years, we analyzed body mass index (BMI) and anonymous parental report of abuse. Abuse was categorized as emotional, physical, or sexual. A sub-sample of 3429 had BMI recorded at 18 years, enabling a longitudinal analysis of BMI trajectories. Using linear and logistic regression analysis, adjusting for sex and family adversity, no association was found between child abuse and BMI, BMI Z-scores, overweight, or obesity, at 13 or 16 years, with all confidence intervals straddling the null. There was weak evidence of a negative association between physical and emotional abuse and BMI trajectories between 13 and 18 years. No relationship was found between child abuse and adolescent obesity in this cohort. This challenges the assumption that adolescent obesity is linked to previous child abuse, as demonstrated for obesity in adult life. A further longitudinal study utilizing both parental and child reports with data record linkage, to improve reporting of abuse, and including neglect as an abuse category, would be desirable.

Changes in aerobic power of women, ages 20-64 yr

NASA Technical Reports Server (NTRS)

Jackson, A. S.; Wier, L. T.; Ayers, G. W.; Beard, E. F.; Stuteville, J. E.; Blair, S. N.

1996-01-01

This study quantified and compared the cross-sectional and longitudinal influence of age, self-report physical activity (SR-PA), and body composition (%fat) on the decline of maximal aerobic power (VO2peak) of women. The cross-sectional sample consisted of 409 healthy women, ages 20-64 yr. The 43 women of the longitudinal sample were from the same population and examined twice, the mean time between tests was 3.7 (+/-2.2) yr. Peak oxygen uptake was determined by indirect calorimetry during a maximal treadmill test. The zero-order correlation of -0.742 between VO2peak and %fat was significantly (P < 0.05) higher then the SR-PA (r = 0.626) and age correlations (r = -0.633). Linear regression defined the cross-sectional age-related decline in VO2peak at 0.537 ml.kg-1.min-1.yr-1. Multiple regression analysis (R = 0.851) showed that adding %fat and SR-PA and their interaction to the regression model reduced the age regression weight of -0.537, to -0.265 ml.kg-1.min-1.yr-1. Statistically controlling for time differences between tests, general linear models analysis showed that longitudinal changes in aerobic power were due to independent changes in %fat and SR-PA, confirming the cross-sectional results. These findings are consistent with men's data from the same lab showing that about 50% of the cross-sectional age-related decline in VO2peak was due to %fat and SR-PA.

Factors Associated with Post-Seasonal Serological Titer and Risk Factors for Infection with the Pandemic A/H1N1 Virus in the French General Population

PubMed Central

Lapidus, Nathanael; de Lamballerie, Xavier; Salez, Nicolas; Setbon, Michel; Delabre, Rosemary M.; Ferrari, Pascal; Moyen, Nanikaly; Gougeon, Marie-Lise; Vely, Frédéric; Leruez-Ville, Marianne; Andreoletti, Laurent; Cauchemez, Simon; Boëlle, Pierre-Yves; Vivier, Éric; Abel, Laurent; Schwarzinger, Michaël; Legeas, Michèle; Le Cann, Pierre; Flahault, Antoine; Carrat, Fabrice

2013-01-01

The CoPanFlu-France cohort of households was set up in 2009 to study the risk factors for infection by the pandemic influenza virus (H1N1pdm) in the French general population. The authors developed an integrative data-driven approach to identify individual, collective and environmental factors associated with the post-seasonal serological H1N1pdm geometric mean titer, and derived a nested case-control analysis to identify risk factors for infection during the first season. This analysis included 1377 subjects (601 households). The GMT for the general population was 47.1 (95% confidence interval (CI): 45.1, 49.2). According to a multivariable analysis, pandemic vaccination, seasonal vaccination in 2009, recent history of influenza-like illness, asthma, chronic obstructive pulmonary disease, social contacts at school and use of public transports by the local population were associated with a higher GMT, whereas history of smoking was associated with a lower GMT. Additionally, young age at inclusion and risk perception of exposure to the virus at work were identified as possible risk factors, whereas presence of an air humidifier in the living room was a possible protective factor. These findings will be interpreted in light of the longitudinal analyses of this ongoing cohort. PMID:23613718

Stability and Change in Farming Plans: Results from a Longitudinal Study of Young Adults.

ERIC Educational Resources Information Center

Lyson, Thomas A.

To examine 2 shortcomings of previous cross-sectional farm recruitment research, the study population of the National Longitudinal Survey of the High School Class of 1972, consisting of 14,112 individuals who completed the base year questionnaire and 3 subsequent follow-up questionnaires, was divided into analytic sub-groups based on senior year…

Predictors of Parent-Reported Attention-Deficit/Hyperactivity Disorder in Children Aged 6-7 Years: A National Longitudinal Study

ERIC Educational Resources Information Center

Sciberras, Emma; Ukoumunne, Obioha C.; Efron, Daryl

2011-01-01

This study examined the prenatal, postnatal and demographic predictors of parent-reported attention-deficit/hyperactivity disorder (ADHD) in an Australian population-based sample. Participants were families participating in the Longitudinal Study of Australian Children. There were approximately even numbers of males (51%) and females (49%) in the…

Longitudinal Investigation of the Relationship among Maternal Victimization, Depressive Symptoms, Social Support, and Children's Behavior and Development

ERIC Educational Resources Information Center

Koverola, Catherine; Papas, Mia A.; Pitts, Steven; Murtaugh, Cristin; Black, Maureen M.; Dubowitz, Howard

2005-01-01

This article is a longitudinal investigation of the relationships between maternal victimization, maternal functioning, and children's behavior and development. Participants include 203 mother-child dyads from a low-income population recruited from pediatric primary care clinics. Data are collected when children are 4 and 8 years of age. Child…

A Longitudinal Investigation of Reading in High-Stakes Tests for Adolescent English Language Learners

ERIC Educational Resources Information Center

Lim, Hyo Jin

2010-01-01

The present study investigated longitudinal changes of the reading achievement among schools populated with English learners. It also examined the heterogeneity in the English learners group in terms of students' performance in high stakes reading tests. Historically, English learners have often been considered the students who are in the process…

Statewide Longitudinal Follow-up Study of Former Secondary Level Vocational Education Students (Project SEE). Report of Accomplishments.

ERIC Educational Resources Information Center

Wright, Calvin E.; Kim, Yungho

A longitudinal followup study, entitled Project Student Employment Experiences (SEE), examined the long-term employment experiences of former vocational education students, especially special needs population students, and the long-term effects of their training. During the project, researchers collected a 3-year followup information file on their…

Are Body Dissatisfaction, Eating Disturbance, and Body Mass Index Predictors of Suicidal Behavior in Adolescents? A Longitudinal Study

ERIC Educational Resources Information Center

Crow, Scott; Eisenberg, Marla E.; Story, Mary; Neumark-Sztainer, Dianne

2008-01-01

Disordered eating, body dissatisfaction, and obesity have been associated cross sectionally with suicidal behavior in adolescents. To determine the extent to which these variables predicted suicidal ideation and attempts, the authors examined these relationships in a longitudinal design. The study population included 2,516 older adolescents and…

College Completion and Participation in a Developmental Math Course for Hispanic and White Non-Hispanic Students

ERIC Educational Resources Information Center

Glazier, Stephen Gene

2011-01-01

Purpose, Scope, and Method of Study. The population of interest in the study consisted of white and Hispanic high school graduates in the United States who attended college and completed a college developmental mathematics course. Data from the National Educational Longitudinal Study of 1988 were employed, and a longitudinal, quasi-experimental…

Longitudinal Associations between Triglycerides and Metabolic Syndrome Components in a Beijing Adult Population, 2007-2012.

PubMed

Tao, Li-Xin; Yang, Kun; Liu, Xiang-Tong; Cao, Kai; Zhu, Hui-Ping; Luo, Yan-Xia; Guo, Jin; Wu, Li-Juan; Li, Xia; Guo, Xiu-Hua

2016-01-01

Longitudinal associations between triglycerides (TG) and other metabolic syndrome (MetS) components have rarely been reported. The purpose was to investigate the longitudinal association between TG and other MetS components with time. The longitudinal study was established in 2007 on individuals who attended health check-ups at Beijing Tongren Hospital and Beijing Xiaotangshan Hospital. Data used in this study was based on 7489 participants who had at least three health check-ups over a period of 5-year follow up. Joint model was used to explore longitudinal associations between TG and other MetS components after adjusted for age. There were positive correlations between TG and other MetS components except for high density lipoprotein (HDL), and the correlations increased with time. A negative correlation was displayed between TG and HDL, and the correlation also increased with time. Among all five pairs of TG and other MetS components, the marginal correlation between TG and body mass index (BMI) was the largest for both men and women. The marginal correlation between TG and fasting plasma glucose was the smallest for men, while the marginal correlation between TG and diastolic blood pressure was the smallest for women. The longitudinal association between TG and other MetS components increased with time. Among five pairs of TG and other MetS components, the longitudinal correlation between TG and BMI was the largest. It is important to closely monitor subjects with high levels of TG and BMI in health check-up population especially for women, because these two components are closely associated with development of hypertension, diabetes, cardiovascular disease and other metabolic diseases.

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

Second International Mathematics Study; Longitudinal, Classroom Process Surveys for Population A: Students, Teachers, and Schools, 1981-1982 [machine-readable data file].

ERIC Educational Resources Information Center

Wolfe, Richard G.

The Second International Mathematics Study (SIMS) of the International Association for the Evaluation of Educational Achievement (IEA) was conducted in 20 countries on two sampled populations: Population A of 13-year-olds and Population B of students studying mathematics in their final year of secondary school. Mathematics achievement was measured…

Built environment change and change in BMI and waist circumference: Multi-ethnic Study of Atherosclerosis.

PubMed

Hirsch, Jana A; Moore, Kari A; Barrientos-Gutierrez, Tonatiuh; Brines, Shannon J; Zagorski, Melissa A; Rodriguez, Daniel A; Diez Roux, Ana V

2014-11-01

To examine longitudinal associations of the neighborhood built environment with objectively measured body mass index (BMI) and waist circumference (WC) in a geographically and racial/ethnically diverse group of adults. This study used data from 5,506 adult participants in the Multi-Ethnic Study of Atherosclerosis, aged 45-84 years in 2000 (baseline). BMI and WC were assessed at baseline and four follow-up visits (median follow-up 9.1 years). Time-varying built environment measures (population density, land-use, destinations, bus access, and street characteristics) were created using Geographic Information Systems. Principal components analysis was used to derive composite scores for three built environment factors. Fixed-effects models, tightly controlling for all time-invariant characteristics, estimated associations between change in the built environment, and change in BMI and WC. Increases in the intensity of development (higher density of walking destinations and population density, and lower percent residential) were associated with less pronounced increases or decreases over time in BMI and WC. Changes in connected retail centers (higher percent retail, higher street connectivity) and public transportation (distance to bus) were not associated with changes in BMI or WC. Longitudinal changes in the built environment, particularly increased density, are associated with decreases in BMI and WC. © 2014 The Obesity Society.

Promising Long-Term Health-Related Quality of Life After High-Dose-Rate Brachytherapy Boost for Localized Prostate Cancer

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

Wahlgren, Thomas; Nilsson, Sten; Lennernaes, Bo

2007-11-01

Purpose: To explore the long-term general and disease-specific health-related quality of life (HRQOL) >5 years after combined radiotherapy for localized prostate cancer, including a high-dose-rate brachytherapy boost and hormonal deprivation therapy. Methods and Materials: Of 196 eligible patients with localized prostate cancer (Stage T1-T3a) consecutively treated with curative radiotherapy at our institution between June 1998 and August 2000, 182 (93%) completed the European Organization for Research and Treatment of Cancer Quality of Life questionnaires QLQ-C30 and QLQ-PR25, including specific questions on fecal incontinence >5 years after treatment in September 2005. A comparison with age-matched normative data was done, as wellmore » as a longitudinal analysis using HRQOL data from a previous study. Results: The analysis included 158 nonrecurrent patients. Comparisons made with normative data showed that physical and role functioning were significantly better statistically and social functioning was significantly worse. Diarrhea and sleep disturbances were more pronounced and pain less pronounced than in a normal male population. The longitudinal analysis of disease-specific HRQOL showed that urinary urgency and erectile problems persisted 5 years after treatment, and nocturia and hormonally dependent symptoms had declined significantly, with a statistically significant difference. Fecal incontinence was recognized by 25% of patients, of whom 80% considered it a minor problem. Conclusion: More than 5 years after combined radiotherapy, irritative urinary problems and erectile dysfunction remain concerns, although severe bowel disturbance and fecal incontinence seem to be minor problems. Longitudinally, a decline mainly in hormonally dependent symptoms was seen. Minor differences in general HRQOL compared with normative data were observed, possibly including 'response shift' effects.« less

Context-dependent survival, fecundity and predicted population-level consequences of brucellosis in African buffalo

USGS Publications Warehouse

Gorsich, Erin E.; Ezenwa, Vanessa O.; Cross, Paul C.; Bengis, Roy G.; Jolles, Anna E.

2015-01-01

Our results suggest that brucellosis infection can potentially result in reduced population growth rates, but because these effects varied with demographic and environmental conditions, they may remain unseen without intensive, longitudinal monitoring.

Mild thyroid hormone excess is associated with a decreased physical function in elderly men

PubMed Central

Ceresini, Graziano; Ceda, Gian Paolo; Lauretani, Fulvio; Maggio, Marcello; Bandinelli, Stefania; Guralnik, Jack M.; Cappola, Anne R.; Usberti, Elisa; Morganti, Simonetta; Valenti, Giorgio; Ferrucci, Luigi

2015-01-01

Introduction In the adult, subclinical hyperthyroidism (Shyper) may alter skeletal muscle mass and strength. However, whether these effects are present in elderly subjects is not known. We explored the relationship between mild hyperthyroidism and physical function in a population-based sample of older persons. Methods In a cross-sectional analysis, calf muscle cross-sectional area (CMA), handgrip strength, nerve conduction velocity (NCV), and Short Physical Performance Battery (SPPB) scores were compared between 364 euthyroid (Eut) and 28 Shyper men as well as between 502 Eut and 39 Shyper women. In a longitudinal analysis, we evaluated the relationship between baseline plasma TSH, FT3 and FT4 and the 3-year change in SPPB score in 304 men and 409 women who were euthyroid at enrolment. Results At the cross-sectional analysis, Shyper men, but not women, had a significantly (p = 0.02) lower SPPB score than Eut controls, although with comparable CMA, grip strength and NCV, and were more likely to have poor physical performance (odds ratio = 2.97, p< 0.05). Longitudinal analysis showed that in Eut men higher baseline FT4 was significantly (p=0.02) predictive of a lower SPPB score at the 3-year follow-up. Conclusion Even a modest thyroid hormone excess is associated with a reduced physical function in elderly men. PMID:21875391

Longitudinal measures of perfluoroalkyl substances (PFAS) in serum of Gullah African Americans in South Carolina: 2003–2013

PubMed Central

Gribble, Matthew O.; Bartell, Scott M.; Kannan, Kurunthachalam; Wu, Qian; Fair, Patricia A.; Kamen, Diane L.

2015-01-01

Background Charleston Harbor has elevated concentrations of PFAS in dolphins, but local human exposure data are limited. Objectives We sought to describe PFAS serum concentrations’ temporal trends among Gullah African American residents of coastal South Carolina. Methods Longitudinal measures of PFAS in blood serum from a Gullah clinical sample, without lupus, were examined using spaghetti plots and visit-to-visit change scores (e.g., differences in concentrations between visits) among the 68 participants with repeated measures available. We also modeled population-level trends among the 71 participants with any data using proportionate percentile models, accounting for clustering through robust standard errors. In a post-hoc analysis we examined heterogeneity of temporal trends by age through mixed-effects models for the log-transformed PFAS compounds. Results Population concentrations of PFOS dropped approximately 9 (95% CI: 8, 10) percent each year over 2003–2013. This was concordant with individual PFOS trajectories (median PFOS change score −21.7 ng/g wet weight, interquartile range of PFOS change scores: −32.8, −14.9) and reports for other populations over this time period. Several other compounds including PFOA, PFHxS, and PFuNDA also showed a population-level decrease. However, examination of individual trajectories suggested substantial heterogeneity. Post-hoc analyses indicated that PFAS trajectories were heterogeneous by age. Conclusions Many PFAS compounds are decreasing in a sample of Gullah African Americans from coastal South Carolina. There may be age differences in the elimination kinetics of PFASs. The possible role of age as a modifier of PFAS serum trends merits further research. PMID:25819541

Apparent Fibre Density: a novel measure for the analysis of diffusion-weighted magnetic resonance images.

PubMed

Raffelt, David; Tournier, J-Donald; Rose, Stephen; Ridgway, Gerard R; Henderson, Robert; Crozier, Stuart; Salvado, Olivier; Connelly, Alan

2012-02-15

This article proposes a new measure called Apparent Fibre Density (AFD) for the analysis of high angular resolution diffusion-weighted images using higher-order information provided by fibre orientation distributions (FODs) computed using spherical deconvolution. AFD has the potential to provide specific information regarding differences between populations by identifying not only the location, but also the orientations along which differences exist. In this work, analytical and numerical Monte-Carlo simulations are used to support the use of the FOD amplitude as a quantitative measure (i.e. AFD) for population and longitudinal analysis. To perform robust voxel-based analysis of AFD, we present and evaluate a novel method to modulate the FOD to account for changes in fibre bundle cross-sectional area that occur during spatial normalisation. We then describe a novel approach for statistical analysis of AFD that uses cluster-based inference of differences extended throughout space and orientation. Finally, we demonstrate the capability of the proposed method by performing voxel-based AFD comparisons between a group of Motor Neurone Disease patients and healthy control subjects. A significant decrease in AFD was detected along voxels and orientations corresponding to both the corticospinal tract and corpus callosal fibres that connect the primary motor cortices. In addition to corroborating previous findings in MND, this study demonstrates the clear advantage of using this type of analysis by identifying differences along single fibre bundles in regions containing multiple fibre populations. Copyright © 2011 Elsevier Inc. All rights reserved.

A longitudinal investigation of nutrition and dietary patterns in children of mothers with eating disorders.

PubMed

Easter, Abigail; Naumann, Ulrike; Northstone, Kate; Schmidt, Ulrike; Treasure, Janet; Micali, Nadia

2013-07-01

To investigate dietary patterns and nutritional intake in children of mothers with eating disorders. Mothers (N = 9423) from a longitudinal general population birth cohort study, the Avon Longitudinal Study of Parents and Children, completed Food Frequency Questionnaires on their children at 3, 4, 7, and 9 years of age. Macronutrient intake was estimated, and dietary patterns were obtained using principal components analysis. Linear regression and mixed-effects models were used to assess dietary patterns and nutritional intake among children of women with lifetime anorexia nervosa (AN, n = 140), bulimia nervosa (BN, n = 170), or AN+BN (n = 71), compared with children of women without eating disorders (unexposed women, n = 9037). Children in the maternal AN and BN groups had higher scores on the "health conscious/vegetarian" dietary pattern compared with unexposed children. Less adherence to the "traditional" dietary pattern was observed in children of exposed mothers, with more pronounced differences in early childhood. Children of women with AN and BN had higher intake of energy and children of women with BN had higher intake of carbohydrates and starch and lower intake of fat, compared with children in the unexposed group. Maternal eating disorders are associated with altered offspring dietary patterns and macronutrient intake. Longitudinal changes in patterns of diet in children of women with eating disorders may increase the risk of weight gain or disordered eating later in life. Copyright © 2013 Mosby, Inc. All rights reserved.

Cross-sectional and Longitudinal Associations between Knee Joint Effusion Synovitis and Knee Pain in Older Adults.

PubMed

Wang, Xia; Jin, Xingzhong; Han, Weiyu; Cao, Yuelong; Halliday, Andrew; Blizzard, Leigh; Pan, Faming; Antony, Benny; Cicuttini, Flavia; Jones, Graeme; Ding, Changhai

2016-01-01

To describe the cross-sectional and longitudinal associations between knee regional effusion synovitis and knee pain in older adults. Data from a population-based random sample (n = 880, mean age 62 yrs, 50% women) were used. Baseline knee joint effusion synovitis was graded (0-3) using T2-weighted magnetic resonance imaging (MRI) in the suprapatellar pouch, central portion, posterior femoral recess, and subpopliteal recess. Effusion synovitis of the whole joint was defined as a score of ≥ 2 in any subregion. Other knee structural (including cartilage, bone marrow, and menisci) lesions were assessed by MRI at baseline. Knee pain was assessed by the Western Ontario and McMaster Universities Osteoarthritis Index questionnaire at baseline and 2.6 years later. Multivariable analyses were performed after adjustment for age, sex, body mass index, and other structural lesions. The prevalence of effusion synovitis was 67%. Suprapatellar pouch effusion synovitis was significantly and independently associated with increased total and nonweight-bearing knee pain in both cross-sectional and longitudinal analyses (for an increase in total knee pain of ≥ 5, RR 1.26 per grade, 95% CI 1.04-1.52), and increased weight-bearing knee pain in longitudinal analysis only. Effusion synovitis in posterior femoral recess and central portion were independently associated with increases in nonweight-bearing pain (RR 1.63 per grade, 95% CI 1.32-2.01 and RR 1.29 per grade, 95% CI 1.01-1.65, respectively) in longitudinal analyses only. Knee joint effusion synovitis has independent associations with knee pain in older adults. Suprapatellar pouch effusion synovitis is associated with nonweight-bearing and weight-bearing knee pain, while posterior femoral recess and central portion effusion synovitis are only associated with nonweight-bearing pain.

PET Imaging of Tau Pathology and Relationship to Amyloid, Longitudinal MRI, and Cognitive Change in Down Syndrome: Results from the Down Syndrome Biomarker Initiative (DSBI).

PubMed

Rafii, Michael S; Lukic, Ana S; Andrews, Randolph D; Brewer, James; Rissman, Robert A; Strother, Stephen C; Wernick, Miles N; Pennington, Craig; Mobley, William C; Ness, Seth; Matthews, Dawn C

2017-01-01

Adults with Down syndrome (DS) represent an enriched population for the development of Alzheimer's disease (AD), which could aid the study of therapeutic interventions, and in turn, could benefit from discoveries made in other AD populations. 1) Understand the relationship between tau pathology and age, amyloid deposition, neurodegeneration (MRI and FDG PET), and cognitive and functional performance; 2) detect and differentiate AD-specific changes from DS-specific brain changes in longitudinal MRI. Twelve non-demented adults, ages 30 to 60, with DS were enrolled in the Down Syndrome Biomarker Initiative (DSBI), a 3-year, observational, cohort study to demonstrate the feasibility of conducting AD intervention/prevention trials in adults with DS. We collected imaging data with 18F-AV-1451 tau PET, AV-45 amyloid PET, FDG PET, and volumetric MRI, as well as cognitive and functional measures and additional laboratory measures. All amyloid negative subjects imaged were tau-negative. Among the amyloid positive subjects, three had tau in regions associated with Braak stage VI, two at stage V, and one at stage II. Amyloid and tau burden correlated with age. The MRI analysis produced two distinct volumetric patterns. The first differentiated DS from normal (NL) and AD, did not correlate with age or amyloid, and was longitudinally stable. The second pattern reflected AD-like atrophy and differentiated NL from AD. Tau PET and MRI atrophy correlated with several cognitive and functional measures. Tau accumulation is associated with amyloid positivity and age, as well as with progressive neurodegeneration measurable using FDG and MRI. Tau correlates with cognitive decline, as do AD-specific hypometabolism and atrophy.

Aging Baby Boomers and the Rising Cost of Chronic Back Pain: Secular Trend Analysis of Longitudinal Medical Expenditures Panel Survey Data for Years 2000 to 2007

PubMed Central

Smith, Monica; Davis, Matthew A.; Stano, Miron; Whedon, James M.

2013-01-01

Objectives The purposes of this study were to analyze data from the longitudinal Medical Expenditures Panel Survey (MEPS) to evaluate the impact of an aging population on secular trends in back pain and chronicity and to provide estimates of treatment costs for patients who used only ambulatory services. Methods Using the MEPS 2-year longitudinal data for years 2000 to 2007, we analyzed data from all adult respondents. Of the total number of MEPS respondent records analyzed (N = 71 838), we identified 12 104 respondents with back pain and further categorized 3842 as chronic cases and 8262 as nonchronic cases. Results Secular trends from the MEPS data indicate that the prevalence of back pain has increased by 29%, whereas chronic back pain increased by 64%. The average age among all adults with back pain increased from 45.9 to 48.2 years; the average age among adults with chronic back pain increased from 48.5 to 52.2 years. Inflation-adjusted (to 2010 dollars) biennial expenditures on ambulatory services for chronic back pain increased by 129% over the same period, from $15.6 billion in 2000 to 2001 to $35.7 billion in 2006 to 2007. Conclusion The prevalence of back pain, especially chronic back pain, is increasing. To the extent that the growth in chronic back pain is caused, in part, by an aging population, the growth will likely continue or accelerate. With relatively high cost per adult with chronic back pain, total expenditures associated with back pain will correspondingly accelerate under existing treatment patterns. This carries implications for prioritizing health policy, clinical practice, and research efforts to improve care outcomes, costs, and cost-effectiveness and for health workforce planning. PMID:23380209

The socioeconomic determinants of HIV incidence: evidence from a longitudinal, population-based study in rural South Africa.

PubMed

Bärnighausen, Till; Hosegood, Victoria; Timaeus, Ian M; Newell, Marie-Louise

2007-11-01

Knowledge of the effect of socioeconomic status on HIV infection in Africa stems largely from cross-sectional studies. Cross-sectional studies suffer from two important limitations: two-way causality between socioeconomic status and HIV serostatus and simultaneous effects of socioeconomic status on HIV incidence and HIV-positive survival time. Both problems are avoided in longitudinal cohort studies. We used data from a longitudinal HIV surveillance and a linked demographic surveillance in a poor rural community in KwaZulu-Natal, South Africa, to investigate the effect of three measures of socioeconomic status on HIV incidence: educational attainment, household wealth categories (based on a ranking of households on an assets index scale) and per capita household expenditure. Our sample comprised of 3325 individuals who tested HIV-negative at baseline and either HIV-negative or -positive on a second test (on average 1.3 years later). In multivariable survival analysis, one additional year of education reduced the hazard of acquiring HIV by 7% (P = 0.017) net of sex, age, wealth, household expenditure, rural vs. urban/periurban residence, migration status and partnership status. Holding other factors equal, members of households that fell into the middle 40% of relative wealth had a 72% higher hazard of HIV acquisition than members of the 40% poorest households (P = 0.012). Per capita household expenditure did not significantly affect HIV incidence (P = 0.669). Although poverty reduction is important for obvious reasons, it may not be as effective as anticipated in reducing the spread of HIV in rural South Africa. In contrast, our results suggest that increasing educational attainment in the general population may lower HIV incidence.

Longitudinal association of hypertension and diabetes mellitus with cognitive functioning in a general 70-year-old population: the SONIC study.

PubMed

Ryuno, Hirochika; Kamide, Kei; Gondo, Yasuyuki; Kabayama, Mai; Oguro, Ryosuke; Nakama, Chikako; Yokoyama, Serina; Nagasawa, Motonori; Maeda-Hirao, Satomi; Imaizumi, Yuki; Takeya, Miyuki; Yamamoto, Hiroko; Takeda, Masao; Takami, Yoichi; Itoh, Norihisa; Takeya, Yasushi; Yamamoto, Koichi; Sugimoto, Ken; Nakagawa, Takeshi; Yasumoto, Saori; Ikebe, Kazunori; Inagaki, Hiroki; Masui, Yukie; Takayama, Michiyo; Arai, Yasumichi; Ishizaki, Tatsuro; Takahashi, Ryutaro; Rakugi, Hiromi

2017-07-01

Both hypertension and diabetes in middle-aged individuals have been suggested to be predictive indicators of cognitive decline. However, the association of hypertension, diabetes and their combination with cognitive functioning is still controversial in older people. The purpose of this study was to investigate the association between cognitive decline and hypertension, diabetes, and their combination in 70-year-old people based on a 3-year longitudinal analysis. Four hundred and fifty-four people aged 70 (±1) years who participated in the Japanese longitudinal cohort study of Septuagenarians, Octogenarians and Nonagenarians Investigation with Centenarians (SONIC) were recruited randomly from a general population and were monitored for 3 years. The data, including most of the demographics, cognitive functioning measured by the Montreal Cognitive Assessment Japanese version (MoCA-J), blood pressure, blood chemistry and other medical histories, were collected at baseline and during the follow-up. The prevalence of hypertension noted in the follow-up survey was significantly higher than than noted at baseline. The mean MoCA-J score at follow-up was not significantly different from the score obtained at baseline. However, the participants with diabetes, especially combined with hypertension at baseline, had significantly lower MoCA-J scores than those without lifestyle-related diseases. The combination of hypertension and diabetes was still a significant risk factor for cognitive decline, considering the MoCA-J scores obtained during the follow-up after adjustments at baseline, relative to sex, body mass index, dyslipidemia, smoking, excessive alcohol intake, antihypertensive treatment and education level (β=-0.14; P<0.01). Our findings indicate that diabetes and the combination of hypertension and diabetes are clear risk factors for future cognitive decline in elderly individuals who are 70 years of age.

A U-Shaped Relationship between Body Mass Index and Dysmenorrhea: A Longitudinal Study

PubMed Central

Ju, Hong; Jones, Mark; Mishra, Gita D.

2015-01-01

Background Both obesity and dysmenorrhea are prevalent among women. Few population-based longitudinal studies investigate the association between body mass index (BMI) and dysmenorrhea yielding mixed results, especially for obesity. This study aims to investigate the long-term association between BMI and dysmenorrhea. Methods 9,688 women from a prospective population-based cohort study were followed for 13 years. Data were collected through self-reported questionnaires. The longitudinal association between dysmenorrhea and BMI or BMI change was investigated by logistic regression analysis using generalized estimating equations to account for the repeated measures. Results When the women were aged 22 to 27 years, approximately 11% were obese, 7% underweight, and 25% reported dysmenorrhea. Compared to women with a normal weight, significantly higher odds of reporting dysmenorrhea were detected for both women who were underweight (odds ratio (OR) 1.34, 95% confidence interval (CI) 1.15, 1.57) and obese (OR 1.22, 95% CI 1.11, 1.35). Compared to women who remained at normal weight or overweight over time, significant risk was detected for women who: remained underweight or obese (OR 1.33, 95% CI 1.20, 1.48), were underweight despite weight gain (OR 1.33, 95% CI 1.12, 1.58), became underweight (OR 1.28, 95% CI 1.02, 1.61). However the higher risk among obese women disappeared when they lost weight (OR 1.06, 95% CI 0.85, 1.32). Conclusions A U-shaped association was revealed between dysmenorrhea and BMI, revealing a higher risk of dysmenorrhea for both underweight and obese women. Maintaining a healthy weight over time may be important for women to have pain-free periods. PMID:26218569

A U-Shaped Relationship between Body Mass Index and Dysmenorrhea: A Longitudinal Study.

PubMed

Ju, Hong; Jones, Mark; Mishra, Gita D

2015-01-01

Both obesity and dysmenorrhea are prevalent among women. Few population-based longitudinal studies investigate the association between body mass index (BMI) and dysmenorrhea yielding mixed results, especially for obesity. This study aims to investigate the long-term association between BMI and dysmenorrhea. 9,688 women from a prospective population-based cohort study were followed for 13 years. Data were collected through self-reported questionnaires. The longitudinal association between dysmenorrhea and BMI or BMI change was investigated by logistic regression analysis using generalized estimating equations to account for the repeated measures. When the women were aged 22 to 27 years, approximately 11% were obese, 7% underweight, and 25% reported dysmenorrhea. Compared to women with a normal weight, significantly higher odds of reporting dysmenorrhea were detected for both women who were underweight (odds ratio (OR) 1.34, 95% confidence interval (CI) 1.15, 1.57) and obese (OR 1.22, 95% CI 1.11, 1.35). Compared to women who remained at normal weight or overweight over time, significant risk was detected for women who: remained underweight or obese (OR 1.33, 95% CI 1.20, 1.48), were underweight despite weight gain (OR 1.33, 95% CI 1.12, 1.58), became underweight (OR 1.28, 95% CI 1.02, 1.61). However the higher risk among obese women disappeared when they lost weight (OR 1.06, 95% CI 0.85, 1.32). A U-shaped association was revealed between dysmenorrhea and BMI, revealing a higher risk of dysmenorrhea for both underweight and obese women. Maintaining a healthy weight over time may be important for women to have pain-free periods.

A population genetic transect of Panicum hallii (Poaceae).

PubMed

Lowry, David B; Purmal, Colin T; Juenger, Thomas E

2013-03-01

Understanding the relationship between climate, adaptation, and population structure is of fundamental importance to botanists because these factors are crucial for the evolution of biodiversity and the response of species to future climate change. Panicum hallii is an emerging model system for perennial grass and bioenergy research, yet very little is known about the relationship between climate and population structure in this system. • We analyzed geographic population differentiation across 39 populations of P. hallii along a longitudinal transect from the savannas of central Texas through the deserts of Arizona and New Mexico. A combination of morphological and genetic (microsatellite) analysis was used to explore patterns of population structure. • We found strong differentiation between high elevation western desert populations and lower elevation eastern populations of P. hallii, with a pronounced break in structure occurring in western Texas. In addition, we confirmed that there are high levels of morphological and genetic structure between previous recognized varieties (var. hallii and var. filipes) within this species. • The results of this study suggest that patterns of population structure within P. hallii may be driven by climatic variation over space. Overall, this study lays the groundwork for future studies on the genetics of local adaptation and reproductive isolation in this system.

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

The Influence of Social Conditions Across the Life Course on the Human Gut Microbiota: A Pilot Project With the Wisconsin Longitudinal Study.

PubMed

Herd, Pamela; Schaeffer, Nora Cate; DiLoreto, Kerryann; Jacques, Karen; Stevenson, John; Rey, Federico; Roan, Carol

2017-12-15

To test the feasibility of collecting and integrating data on the gut microbiome into one of the most comprehensive longitudinal studies of aging and health, the Wisconsin Longitudinal Study (WLS). The long-term goal of this integration is to clarify the contribution of social conditions in shaping the composition of the gut microbiota late in life. Research on the microbiome, which is considered to be of parallel importance to human health as the human genome, has been hindered by human studies with nonrandomly selected samples and with limited data on social conditions over the life course. No existing population-based longitudinal study had collected fecal specimens. Consequently, we created an in-person protocol to collect stool specimens from a subgroup of WLS participants. We collected 429 stool specimens, yielding a 74% response rate and one of the largest human samples to date. The addition of data on the gut microbiome to the WLS-and to other population based longitudinal studies of aging-is feasible, under the right conditions, and can generate innovative research on the relationship between social conditions and the gut microbiome. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Temporal Patterns of Variable Relationships in Person-Oriented Research: Longitudinal Models of Configural Frequency Analysis

ERIC Educational Resources Information Center

von Eye, Alexander; Mun, Eun Young; Bogat, G. Anne

2008-01-01

This article reviews the premises of configural frequency analysis (CFA), including methods of choosing significance tests and base models, as well as protecting [alpha], and discusses why CFA is a useful approach when conducting longitudinal person-oriented research. CFA operates at the manifest variable level. Longitudinal CFA seeks to identify…

Violence against Pregnant Women Can Increase the Risk of Child Abuse: A Longitudinal Study

ERIC Educational Resources Information Center

Chan, Ko Ling; Brownridge, Douglas A.; Fong, Daniel Y. T.; Tiwari, Agnes; Leung, Wing Cheong; Ho, Pak Chung

2012-01-01

Objective: To assess the impact of intimate partner violence (IPV) against pregnant women on subsequent perpetration of child abuse and neglect (CAN) by parents; and to test the mediation effect of recent IPV on the link between IPV during pregnancy and subsequent CAN. Methods: This study was a longitudinal follow-up of a population-based study on…

Are Family Meal Patterns Associated with Overall Diet Quality during the Transition from Early to Middle Adolescence?

ERIC Educational Resources Information Center

Burgess-Champoux, Teri L.; Larson, Nicole; Neumark-Sztainer, Dianne; Hannan, Peter J.; Story, Mary

2009-01-01

Objective: To examine longitudinal associations of participation in regular family meals (greater than or equal to 5 meals/week) with eating habits and dietary intake during adolescence. Design: Population-based, longitudinal study (Project EAT: Eating Among Teens). Surveys were completed in Minnesota classrooms at Time 1 (1998-1999) and by mail…

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…

A Multidimensional Model of School Dropout from an 8-Year Longitudinal Study in a General High School Population

ERIC Educational Resources Information Center

Fortin, Laurier; Marcotte, Diane; Diallo, Thierno; Potvin, Pierre; Royer, Egide

2013-01-01

This study tests an empirical multidimensional model of school dropout, using data collected in the first year of an 8-year longitudinal study, with first year high school students aged 12-13 years. Structural equation modeling analyses show that five personal, family, and school latent factors together contribute to school dropout identified at…

Researching Special Populations: Retention of Latino Gay and Bisexual Men and Transgender Persons in Longitudinal Health Research

ERIC Educational Resources Information Center

Kuhns, L. M.; Vazquez, R.; Ramirez-Valles, J.

2008-01-01

Few studies have sought to assess predictors of retention of racial/ethnic or sexual minorities in longitudinal health research. The purpose of this study is to investigate predictors of retention of Latino gay and bisexual men and transgender (GBT) research participants after the baseline interview. Data come from a sample of 643 Latino GBT…

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…

A Longitudinal Examination of the Psychoeducational, Neurocognitive, and Psychiatric Functioning in Children with 22q11.2 Deletion Syndrome

ERIC Educational Resources Information Center

Hooper, Stephen R.; Curtiss, Kathleen; Schoch, Kelly; Keshavan, Matcheri S.; Allen, Andrew; Shashi, Vandana

2013-01-01

The present study sought to examine the longitudinal psychoeducational, neurocognitive, and psychiatric outcomes of children and adolescents with chromosome 22q11.2 deletion syndrome (22q11DS), a population with a high incidence of major psychiatric illnesses appearing in late adolescence/early adulthood. Little is known of the developmental…

Can Language Attitudes Be Improved? A Longitudinal Study of Immigrant Students in Catalonia (Spain)

ERIC Educational Resources Information Center

Ianos, Maria-Adelina; Huguet, Ángel; Janés, Judit; Lapresta, Cecilio

2017-01-01

This study explores changes in attitudes towards Catalan, Spanish, and English over a 2-year period, on the part of secondary education students of immigrant origin residing in Catalonia. It aims to provide new data by adopting a longitudinal design and by focusing on the immigrant population, which has raised new challenges for the Catalan…

Social relationships and risk of dementia: A systematic review and meta-analysis of longitudinal cohort studies.

PubMed

Kuiper, Jisca S; Zuidersma, Marij; Oude Voshaar, Richard C; Zuidema, Sytse U; van den Heuvel, Edwin R; Stolk, Ronald P; Smidt, Nynke

2015-07-01

It is unclear to what extent poor social relationships are related to the development of dementia. A comprehensive systematic literature search identified 19 longitudinal cohort studies investigating the association between various social relationship factors and incident dementia in the general population. Relative risks (RRs) with 95% confidence intervals (CIs) were pooled using random-effects meta-analysis. Low social participation (RR: 1.41 (95% CI: 1.13-1.75)), less frequent social contact (RR: 1.57 (95% CI: 1.32-1.85)), and more loneliness (RR: 1.58 (95% CI: 1.19-2.09)) were statistically significant associated with incident dementia. The results of the association between social network size and dementia were inconsistent. No statistically significant association was found for low satisfaction with social network and the onset of dementia (RR: 1.25 (95% CI: 0.96-1.62). We conclude that social relationship factors that represent a lack of social interaction are associated with incident dementia. The strength of the associations between poor social interaction and incident dementia is comparable with other well-established risk factors for dementia, including low education attainment, physical inactivity, and late-life depression. Copyright © 2015 Elsevier B.V. All rights reserved.

Reconstructing genealogies of serial samples under the assumption of a molecular clock using serial-sample UPGMA.

PubMed

Drummond, A; Rodrigo, A G

2000-12-01

Reconstruction of evolutionary relationships from noncontemporaneous molecular samples provides a new challenge for phylogenetic reconstruction methods. With recent biotechnological advances there has been an increase in molecular sequencing throughput, and the potential to obtain serial samples of sequences from populations, including rapidly evolving pathogens, is fast being realized. A new method called the serial-sample unweighted pair grouping method with arithmetic means (sUPGMA) is presented that reconstructs a genealogy or phylogeny of sequences sampled serially in time using a matrix of pairwise distances. The resulting tree depicts the terminal lineages of each sample ending at a different level consistent with the sample's temporal order. Since sUPGMA is a variant of UPGMA, it will perform best when sequences have evolved at a constant rate (i.e., according to a molecular clock). On simulated data, this new method performs better than standard cluster analysis under a variety of longitudinal sampling strategies. Serial-sample UPGMA is particularly useful for analysis of longitudinal samples of viruses and bacteria, as well as ancient DNA samples, with the minimal requirement that samples of sequences be ordered in time.

Global Longitudinal Strain Using Speckle-Tracking Echocardiography as a Mortality Predictor in Sepsis: A Systematic Review.

PubMed

Vallabhajosyula, Saraschandra; Rayes, Hamza A; Sakhuja, Ankit; Murad, Mohammad Hassan; Geske, Jeffrey B; Jentzer, Jacob C

2018-01-01

The data on speckle-tracking echocardiography (STE) in patients with sepsis are limited. This systematic review from 1975 to 2016 included studies in adults and children evaluating cardiovascular dysfunction in sepsis, severe sepsis, and septic shock utilizing STE for systolic global longitudinal strain (GLS). The primary outcome was short- or long-term mortality. Given the significant methodological and statistical differences between published studies, combining the data using meta-analysis methods was not appropriate. A total of 120 studies were identified, with 5 studies (561 patients) included in the final analysis. All studies were prospective observational studies using the 2001 criteria for defining sepsis. Three studies demonstrated worse systolic GLS to be associated with higher mortality, whereas 2 did not show a statistically significant association. Various cutoffs between -10% and -17% were used to define abnormal GLS across studies. This systematic review revealed that STE may predict mortality in patients with sepsis; however, the strength of evidence is low due to heterogeneity in study populations, GLS technologies, cutoffs, and timing of STE. Further dedicated studies are needed to understand the optimal application of STE in patients with sepsis.

Reciprocal Influences Between Maternal Parenting and Child Adjustment in a High-risk Population: A Five-Year Cross-Lagged Analysis of Bidirectional Effects

PubMed Central

Barbot, Baptiste; Crossman, Elizabeth; Hunter, Scott R.; Grigorenko, Elena L.; Luthar, Suniya S.

2014-01-01

This study examines longitudinally the bidirectional influences between maternal parenting (behaviors and parenting stress) and mothers' perceptions of their children's adjustment, in a multivariate approach. Data was gathered from 361 low-income mothers (many with psychiatric diagnoses) reporting on their parenting behavior, parenting stress and their child's adjustment, in a two-wave longitudinal study over 5 years. Measurement models were developed to derive four broad parenting constructs (Involvement, Control, Rejection, and Stress) and three child adjustment constructs (Internalizing problems, Externalizing problems, and Social competence). After measurement invariance of these constructs was confirmed across relevant groups and over time, both measurement models were integrated in a single crossed-lagged regression analysis of latent constructs. Multiple reciprocal influence were observed between parenting and perceived child adjustment over time: Externalizing and internalizing problems in children were predicted by baseline maternal parenting behaviors, while child social competence was found to reduce parental stress and increase parental involvement and appropriate monitoring. These findings on the motherhood experience are discussed in light of recent research efforts to understand mother-child bi-directional influences, and their potential for practical applications. PMID:25089759

Profiles of rural longitudinal integrated clerkship students: a descriptive study of six consecutive student cohorts *.

PubMed

Brooks, Kathleen D; Eley, Diann S; Zink, Therese

2014-02-01

Medical schools worldwide are challenged to address the rural primary care workforce shortage by creating community-engaged curricula to nurture student interest in rural practice. To examine the personal characteristics of six consecutive rural longitudinal integrated clerkship student cohorts to understand whom the programs attract and select and thus inform the development of such programs. A cross-sectional cohort design was used. Six cohorts (2007-2012) completed a survey on demographics and factors that influenced their choice of rural primary care. The Temperament and Character Inventory was used to measure personality. Analysis was mainly descriptive. Where appropriate univariate analysis compared variables between groups. Sample size was 205 with the majority female (61%), between 25 and 29 years (64%), single (60%) and lived longest in rural communities with populations less than 20,000 (60%). Rural lifestyle, background and desire to work in underserved areas were noted to impact rural medicine interest. Professional satisfaction, personal and professional goals and family needs had the highest impact on career decisions, and financial concerns lowest. The stability of students' personal characteristics across cohorts and the workforce outcomes of this program suggest the recruitment process successfully nurtures students who will fit well into future rural practice.

Gender and education impact on brain aging: a general cognitive factor approach.

PubMed

Proust-Lima, Cécile; Amieva, Hélène; Letenneur, Luc; Orgogozo, Jean-Marc; Jacqmin-Gadda, Hélène; Dartigues, Jean-François

2008-09-01

In cognitive aging research, the study of a general cognitive factor has been shown to have a substantial explanatory power over the study of isolated tests. The authors aimed at differentiating the impact of gender and education on global cognitive change with age from their differential impact on 4 psychometric tests using a new latent process approach, which intermediates between a single-factor longitudinal model for sum scores and an item-response theory approach for longitudinal data. The analysis was conducted on a sample of 2,228 subjects from PAQUID, a population-based cohort of older adults followed for 13 years with repeated measures of cognition. Adjusted for vascular factors, the analysis confirmed that women performed better in tests involving verbal components, while men performed better in tests involving visuospatial skills. In addition, the model suggested that women had a slightly steeper global cognitive decline with oldest age than men, even after excluding incident dementia or death. Subjects with higher education exhibited a better mean score for the 4 tests, but this difference tended to attenuate with age for tests involving a speed component. (c) 2008 APA, all rights reserved

A longitudinal study of Latino and non-Hispanic mothers' and fathers' depressive symptoms and its association with parent-child communication.

PubMed

De Luca, Susan M; Yueqi, Yan; DiCorcia, Daley; Padilla, Yolanda

2018-02-01

Roughly 8% of the U.S. population report moderate or severe depression for two or more weeks and Latinos (3.7%) report higher rates of severe depression compared to non-Hispanic whites (2.6%) (Pratt and Brody, 2014). As the Latino population continues to grow in the U.S., there is little research on the manifestations for depression, and how this affects the family system longitudinally. Based on data from the Fragile Families and Child Wellbeing Study, a 3-step latent class analysis examined the association of self-reported parental depressive symptoms and their children's perceived levels of closeness and openness to communicate with their parents over 9 years (N=3956 families). Latino parents reported four different depressive patterns, while non-Hispanic parents were more diversified and had six patterns in terms of latent class analysis. Latinos reported episodic symptoms, while NH parents were more likely to report chronic depressive symptoms over time. Regardless of race/ethnicity, parental depressive symptoms negatively affected their children's reported level of parental closeness and openness to communicate with mothers and fathers. As with any self-report data, the risk of social desirability bias is likely still present. Additionally, these results cannot be generalized to the broader U.S. Due to the different mental health presentations over 9 years, and following the federal initiatives (National Institute of Mental Health, 2015) of early and consistent surveillance, we advise that clinicians and primary care physicians screen for depressive symptoms at least yearly. Copyright © 2017 Elsevier B.V. All rights reserved.

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.

Changes in population characteristics and their implication on public health research.

PubMed

Du, Ping; Coles, F Bruce; O'Campo, Patricia; McNutt, Louise-Anne

2007-07-10

Population estimates are generally drawn from one point in time to study disease trends over time; changes in population characteristics over time are usually not assessed and included in the study design. We evaluated whether population characteristics remained static and assessed the degree of population shifts over time. The analysis was based on the New York State 1990 and 2000 census data with adjustments for changes in geographic boundaries. Differences in census tract information were quantified by calculating the mean, median, standard deviation, and the percent of change for each population characteristic. Between 1990 and 2000, positive and negative fluctuations in population size created a U-shaped bimodal pattern of population change which increased the disparities in demographics and socioeconomic status for many census tracts. While 268 (10%) census tracts contracted by 10%, twice as many census tracts (21%, N = 557) grew at least 10%. Notably, the non-Hispanic African-American population grew 10% or more in 152 tracts. Although there were overall reductions in working class and undereducated populations and gains in incomes, most census tracts experienced growing income inequalities and an increased poverty rate. These changes were most pronounced in urban census tracts. Differences in population characteristics in a decade showed growing disparities in demographics and socioeconomic status. This study elucidates that important population shifts should be taken into account when conducting longitudinal research.

Changes in population characteristics and their implication on public health research

PubMed Central

Du, Ping; Coles, F Bruce; O'Campo, Patricia; McNutt, Louise-Anne

2007-01-01

Population estimates are generally drawn from one point in time to study disease trends over time; changes in population characteristics over time are usually not assessed and included in the study design. We evaluated whether population characteristics remained static and assessed the degree of population shifts over time. The analysis was based on the New York State 1990 and 2000 census data with adjustments for changes in geographic boundaries. Differences in census tract information were quantified by calculating the mean, median, standard deviation, and the percent of change for each population characteristic. Between 1990 and 2000, positive and negative fluctuations in population size created a U-shaped bimodal pattern of population change which increased the disparities in demographics and socioeconomic status for many census tracts. While 268 (10%) census tracts contracted by 10%, twice as many census tracts (21%, N = 557) grew at least 10%. Notably, the non-Hispanic African-American population grew 10% or more in 152 tracts. Although there were overall reductions in working class and undereducated populations and gains in incomes, most census tracts experienced growing income inequalities and an increased poverty rate. These changes were most pronounced in urban census tracts. Differences in population characteristics in a decade showed growing disparities in demographics and socioeconomic status. This study elucidates that important population shifts should be taken into account when conducting longitudinal research. PMID:17623097

Changes in the bacterial community in the fermentation process of kôso, a Japanese sugar-vegetable fermented beverage.

PubMed

Chiou, Tai-Ying; Suda, Wataru; Oshima, Kenshiro; Hattori, Masahira; Takahashi, Tomoya

2017-02-01

Kôso is a Japanese fermented beverage made with over 20 kinds of vegetables, mushrooms, and sugars. The changes in the bacterial population of kôso during fermentation at 25 °C over a period of 10 days were studied using 454 pyrosequencing of the 16S rRNA gene. The analysis detected 224 operational taxonomic units (OTUs) clustered from 8 DNA samples collected on days 0, 3, 7, and 10 from two fermentation batches. Proteobacteria were the dominant phylum in the starting community, but were replaced by Firmicutes within three days. Seventy-eight genera were identified from the 224 OTUs, in which Bifidobacterium, Leuconostoc, Lactococcus, and Lactobacillus dominated, accounting for over 96% of the total bacterial population after three days' fermentation. UniFrac-Principal Coordinate Analysis of longitudinal fermented samples revealed dramatic changes in the bacterial community in kôso, resulting in significantly low diversity at the end of fermentation as compared with the complex starting community.

An analysis of the effects of aeroelasticity on static longitudinal stability and control of a swept-wing airplane

NASA Technical Reports Server (NTRS)

Skoog, Richard B

1957-01-01

A theoretical analysis has been made of the effects of aeroelasticity on the static longitudinal stability and elevator angle required for balance of an airplane. The analysis is based on the familiar stability equation expressing the contribution of wing and tail to longitudinal stability. Effects of wing, tail, and fuselage flexibility are considered. Calculated effects are shown for a swept-wing bomber of relatively high flexibility.

Composite marginal quantile regression analysis for longitudinal adolescent body mass index data.

PubMed

Yang, Chi-Chuan; Chen, Yi-Hau; Chang, Hsing-Yi

2017-09-20

Childhood and adolescenthood overweight or obesity, which may be quantified through the body mass index (BMI), is strongly associated with adult obesity and other health problems. Motivated by the child and adolescent behaviors in long-term evolution (CABLE) study, we are interested in individual, family, and school factors associated with marginal quantiles of longitudinal adolescent BMI values. We propose a new method for composite marginal quantile regression analysis for longitudinal outcome data, which performs marginal quantile regressions at multiple quantile levels simultaneously. The proposed method extends the quantile regression coefficient modeling method introduced by Frumento and Bottai (Biometrics 2016; 72:74-84) to longitudinal data accounting suitably for the correlation structure in longitudinal observations. A goodness-of-fit test for the proposed modeling is also developed. Simulation results show that the proposed method can be much more efficient than the analysis without taking correlation into account and the analysis performing separate quantile regressions at different quantile levels. The application to the longitudinal adolescent BMI data from the CABLE study demonstrates the practical utility of our proposal. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Associations between sleep disturbance and mental health status: a longitudinal study of Japanese junior high school students.

PubMed

Kaneita, Yoshitaka; Yokoyama, Eise; Harano, Satoru; Tamaki, Tetsuo; Suzuki, Hiroyuki; Munezawa, Takeshi; Nakajima, Hiromi; Asai, Takami; Ohida, Takashi

2009-08-01

A limited number of longitudinal studies have addressed the association between sleep disturbance and mental health status among adolescents. To examine whether each of these is a risk factor for the onset of the other, we conducted a prospective longitudinal study of Japanese adolescents. In 2004, we performed a baseline study of students attending three private junior high schools in Tokyo, and in 2006, a follow-up study was performed on the same population. The mean age of the subjects was 13 years. The Pittsburgh Sleep Quality Index was used to evaluate sleep disturbance, and the 12-item General Health Questionnaire was used to evaluate mental health status. The subjects were 698 students, of whom 516 were suitable for analysis. The incidence of newly developed poor mental health status during the 2 years leading to the follow-up study was 35.1%. New onset of poor mental health status was significantly associated with new onset of sleep disturbance and lasting sleep disturbance. The incidence of sleep disturbance during the 2 years leading to the follow-up study was 33.3%. New onset of sleep disturbance was significantly associated with new onset of poor mental health status and lasting poor mental health status. Sleep disturbance and poor mental health status increase each other's onset risk.

Longitudinal Effects of Health-Harming and Health-Protective Behaviors within Adolescent Romantic Dyads

PubMed Central

Aalsma, Matthew C.; Carpentier, Melissa; Azzouz, Faouzi; Fortenberry, Dennis

2012-01-01

Most models exploring adolescent health behavior have focused on individual influences to understand behavior change. The goal of the current study was to assess the role of adolescent romantic partners on the expression of health behavior. Our sample utilized two waves of data from the US National Longitudinal Study of Adolescent Health (1994, 1996), which included 80 romantic dyads (160 individuals). A longitudinal multilevel analysis was conducted. We assessed individual and romantic partner health-harming behaviors (i.e., delinquency, alcohol use, smoking, and marijuana use), health-protective behaviors (i.e., physical activity, physical inactivity, sleep patterns, seatbelt use, and contraception motivations), as well as the role of gender and age. Participants average age was 16 years at baseline. We found evidence for partner similarity and partner influence with the majority of health-harming behaviors. Specifically, partner influence was evident for smoking and alcohol use with partner influence approaching significance for marijuana use. We found limited evidence for partner similarity and partner influence for health-protective behaviors. The importance of assessing romantic dyads was evident in these data. Interventions focusing on health-harming behavior for adolescent populations are important public health goals. It is recommended that future intervention efforts with adolescent health-harming behaviors should target not only peers, but also consider the role of romantic partners. PMID:22424832

Examining the work–crime association in emerging adulthood: A longitudinal analysis based on a Dutch population sample

PubMed Central

Wensveen, Maaike; Palmen, Hanneke; Blokland, Arjan; Meeus, Wim

2016-01-01

Social control theory links being employed with reduced criminal behaviour. In particular, the indirect social control generated by the perceived benefits of the current job are expected to underlie the work–crime association. Features specific to the emerging adult period, however, call into question the strength of the work–crime association during this new life stage. This study uses data from the Utrecht Study of Adolescent Development (USAD), a longitudinal self-report study among 669 men and women aged 18 to 24 at the start of the study to examine the extent to which working a paid job is associated with reduced levels of delinquency and crime, and the extent to which this association is conditional on individual job perceptions. We also test for gender differences in these associations. Results indicate that for men – but not for women – paid work is associated with lower levels of delinquency and crime, but only from age 24 onwards. PMID:28781582

Social support at work and leisure time and its association with self-rated health and sickness absence.

PubMed

Falkenberg, A; Nyfjäll, M; Hellgren, C; Vingård, E

2012-01-01

The aim of this longitudinal study is to investigate how different aspects of social support at work and in leisure time are associated with self rated health and sickness absence. The 541 participants in the study were representative for a working population in the public sector in Sweden with a majority being woman. Most of the variables were created from data from a questionnaire in March-April 2005. There were four independent variables and two dependent variables. The dependent were based on data from November 2006. A logistic regression model was used for the analysis of associations. A separate model was adapted for each of the explanatory variables for each outcome, which gave five models per independent variable. The study has given a greater awareness of the importance of employees receiving social support, regardless of type of support or from whom the support is coming. Social support has a strong association with SRH in a longitudinal perspective and no association between social support and sickness absence.

Regression Models for the Analysis of Longitudinal Gaussian Data from Multiple Sources

PubMed Central

O’Brien, Liam M.; Fitzmaurice, Garrett M.

2006-01-01

We present a regression model for the joint analysis of longitudinal multiple source Gaussian data. Longitudinal multiple source data arise when repeated measurements are taken from two or more sources, and each source provides a measure of the same underlying variable and on the same scale. This type of data generally produces a relatively large number of observations per subject; thus estimation of an unstructured covariance matrix often may not be possible. We consider two methods by which parsimonious models for the covariance can be obtained for longitudinal multiple source data. The methods are illustrated with an example of multiple informant data arising from a longitudinal interventional trial in psychiatry. PMID:15726666

A Genome-Wide Metabolic QTL Analysis in Europeans Implicates Two Loci Shaped by Recent Positive Selection

PubMed Central

Nicholson, George; Rantalainen, Mattias; Li, Jia V.; Maher, Anthony D.; Malmodin, Daniel; Ahmadi, Kourosh R.; Faber, Johan H.; Barrett, Amy; Min, Josine L.; Rayner, N. William; Toft, Henrik; Krestyaninova, Maria; Viksna, Juris; Neogi, Sudeshna Guha; Dumas, Marc-Emmanuel; Sarkans, Ugis; Donnelly, Peter; Illig, Thomas; Adamski, Jerzy; Suhre, Karsten; Allen, Maxine; Zondervan, Krina T.; Spector, Tim D.; Nicholson, Jeremy K.; Lindon, John C.

2011-01-01

We have performed a metabolite quantitative trait locus (mQTL) study of the 1H nuclear magnetic resonance spectroscopy (1H NMR) metabolome in humans, building on recent targeted knowledge of genetic drivers of metabolic regulation. Urine and plasma samples were collected from two cohorts of individuals of European descent, with one cohort comprised of female twins donating samples longitudinally. Sample metabolite concentrations were quantified by 1H NMR and tested for association with genome-wide single-nucleotide polymorphisms (SNPs). Four metabolites' concentrations exhibited significant, replicable association with SNP variation (8.6×10−11

Diabetes mellitus increases the risk of rotator cuff tear repair surgery: A population-based cohort study.

PubMed

Huang, Shih-Wei; Wang, Wei-Te; Chou, Lin-Chuan; Liou, Tsan-Hon; Chen, Yi-Wen; Lin, Hui-Wen

Rotator cuff tears are the most common cause of shoulder disability in people older than 50years, and surgical intervention is usually required for restoring functioning. However, in patients undergoing rotator cuff repair surgery, patients with DM had poorer functional outcomes than those without DM, and hence, DM is one of the possible risks factor for rotator cut off tear. The aim of this population-based study was to investigate the relationship between DM and the risk of rotator cuff tear in patients receiving rotator cuff repair surgery. In this retrospective longitudinal population-based 7-year cohort study, we investigated the risk of rotator cuff repair surgery in patients with DM. We performed a case-control matched analysis by using data from the Taiwan Longitudinal Health Insurance Database 2005. Patients were enrolled on the basis of the International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic codes for DM between January 1, 2004, and December 31, 2007. The prevalence and the adjusted hazard ratios (HRs) of a rotator cuff repair surgery in patients with and without DM were estimated according to the Cox proportional hazard regression analysis using the frailty model. The DM and non-DM cohorts comprised 58,652 patients with DM and 117,304 (1:2) patients without DM after matching for age and sex. The incidence of rotator cuff repair surgery was 41 per 100,000 and 26 per 100,000 person-years in the DM and non-DM cohorts, respectively. The HR of rotator cuff repair surgery during the follow-up period was 1.56 (95% confidence interval [CI] 1.25-1.93, p<0.001) for patients with DM. After adjustment for covariates, the adjusted HR of rotator cuff repair surgery was 1.33 (95% CI, 1.05-1.68, p<0.001) in the DM cohort. DM is an independent risk factor for rotator cuff tear repair surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

A Systematic Review and Meta-Analysis of The Effect of Low Vitamin D on Cognition.

PubMed

Goodwill, Alicia M; Szoeke, Cassandra

2017-10-01

With an aging population and no cure for dementia on the horizon, risk factor modification prior to disease onset is an urgent health priority. Therefore, this review examined the effect of low vitamin D status or vitamin D supplementation on cognition in midlife and older adults without a diagnosis of dementia. Systematic review and random effect meta-analysis. Observational (cross-sectional and longitudinal cohort) studies comparing low and high vitamin D status and interventions comparing vitamin D supplementation with a control group were included in the review and meta-analysis. Studies including adults and older adults without a dementia diagnosis were included. Medline (PubMed), AMED, Psych INFO, and Cochrane Central databases were searched for articles until August 2016. The Newcastle-Ottawa Scale and Physiotherapy Evidence Database assessed methodological quality of all studies. Twenty-six observational and three intervention studies (n = 19-9,556) were included in the meta-analysis. Low vitamin D was associated with worse cognitive performance (OR = 1.24, CI = 1.14-1.35) and cognitive decline (OR = 1.26, CI = 1.09-1.23); with cross-sectional yielding a stronger effect compared to longitudinal studies. Vitamin D supplementation showed no significant benefit on cognition compared with control (SMD = 0.21, CI = -0.05 to 0.46). Observational evidence demonstrates low vitamin D is related to poorer cognition; however, interventional studies are yet to show a clear benefit from vitamin D supplementation. From the evidence to date, there is likely a therapeutic age window relevant to the development of disease and therefore vitamin D therapy. Longitudinal lifespan studies are necessary to depict the optimal timing and duration in which repletion of vitamin D may protect against cognitive decline and dementia in aging, to better inform trials and practice towards a successful therapy. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

Clonotype and repertoire changes drive the functional improvement of HIV-specific CD8 T cell populations under conditions of limited antigenic stimulation

PubMed Central

Janbazian, Loury; Price, David A.; Canderan, Glenda; Filali-Mouhim, Abdelali; Asher, Tedi E.; Ambrozak, David R.; Scheinberg, Phillip; Boulassel, Mohamad Rachid; Routy, Jean-Pierre; Koup, Richard A.; Douek, Daniel C.; Sekaly, Rafick-Pierre; Trautmann, Lydie

2011-01-01

Persistent exposure to cognate antigen leads to the functional impairment and exhaustion of HIV-specific CD8 T cells. Antigen withdrawal, due either to antiretroviral treatment or the emergence of epitope escape mutations, causes HIV-specific CD8 T cell responses to wane over time. However, this process does not continue to extinction, and residual CD8 T cells likely play an important role in the control of HIV replication. Here, we conducted a longitudinal analysis of clonality, phenotype and function to define the characteristics of HIV-specific CD8 T cell populations that persist under conditions of limited antigenic stimulation. Antigen decay was associated with dynamic changes in the TCR repertoire, increased expression of CD45RA and CD127, decreased expression of PD-1 and the emergence of poly-functional HIV-specific CD8 T cells. High definition analysis of individual clonotypes revealed that the antigen loss-induced gain of function within HIV-specific CD8 T cell populations could be attributed to two non-exclusive mechanisms: (i) functional improvement of persisting clonotypes; and, (ii) recruitment of particular clonotypes endowed with superior functional capabilities. PMID:22210916

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.…

Attrition in a Large Scale Longitudinal Study of the Elderly: The Role of Health-Status Variables.

ERIC Educational Resources Information Center

Horgas, Ann L.; And Others

In a longitudinal study, subject attrition constitutes a potential threat to the usefulness of data collected from subjects remaining in later waves of the study. If attrition is selective, then the sample at later waves of the study may be representative of a different population than that represented at the outset of the study. This study…

A Prospective Longitudinal Study of Shyness from Infancy to Adolescence: Stability, Age-Related Changes, and Prediction of Socio-Emotional Functioning

ERIC Educational Resources Information Center

Karevold, Evalill; Ystrom, Eivind; Coplan, Robert J.; Sanson, Ann V.; Mathiesen, Kristin S.

2012-01-01

This longitudinal, population-based and prospective study investigated the stability, age-related changes, and socio-emotional outcomes of shyness from infancy to early adolescence. A sample of 921 children was followed from ages 1.5 to 12.5 years. Parent-reported shyness was assessed at five time points and maternal- and self-reported social…

Preschool Affects Longer Term Literacy and Numeracy: Results from a General Population Longitudinal Study in Northern Ireland

ERIC Educational Resources Information Center

Melhuish, Edward; Quinn, Louise; Sylva, Kathy; Sammons, Pam; Siraj-Blatchford, Iram; Taggart, Brenda

2013-01-01

The Effective Pre-school Provision in Northern Ireland (EPPNI) project is a longitudinal study of child development from 3 to 11 years. It is one of the first large-scale UK projects to investigate the effects of different kinds of preschool provision, and to relate experience in preschool to child development. In EPPNI, 683 children were randomly…

Prenatal Stress and Risk of Febrile Seizures in Children: A Nationwide Longitudinal Study in Denmark

ERIC Educational Resources Information Center

Li, Jiong; Olsen, Jorn; Obel, Carsten; Christensen, Jakob; Precht, Dorthe Hansen; Vestergaard, Mogens

2009-01-01

We aimed to examine whether exposure to prenatal stress following maternal bereavement is associated with an increased risk of febrile seizures. In a longitudinal population-based cohort study, we followed 1,431,175 children born in Denmark. A total of 34,777 children were born to women who lost a close relative during pregnancy or within 1 year…

Incentivised chronic disease management and the inverse equity hypothesis: findings from a longitudinal analysis of Scottish primary care practice-level data.

PubMed

Lowrie, Richard; McConnachie, Alex; Williamson, Andrea E; Kontopantelis, Evangelos; Forrest, Marie; Lannigan, Norman; Mercer, Stewart W; Mair, Frances S

2017-04-11

The inverse equity hypothesis asserts that new health policies initially widen inequality, then attenuate inequalities over time. Since 2004, the UK's pay-for-performance scheme for chronic disease management (CDM) in primary care general practices (the Quality and Outcomes Framework) has permitted practices to except (exclude) patients from attending annual CDM reviews, without financial penalty. Informed dissent (ID) is one component of exception rates, applied to patients who have not attended due to refusal or non-response to invitations. 'Population achievement' describes the proportion receiving care, in relation to those eligible to receive it, including excepted patients. Examination of exception reporting (including ID) and population achievement enables the equity impact of the UK pay-for-performance contract to be assessed. We conducted a longitudinal analysis of practice-level rates and of predictors of ID, overall exceptions and population achievement for CDM to examine whether the inverse equity hypothesis holds true. We carried out a retrospective, longitudinal study using routine primary care data, analysed by multilevel logistic regression. Data were extracted from 793 practices (83% of Scottish general practices) serving 4.4 million patients across Scotland from 2010/2011 to 2012/2013, for 29 CDM indicators covering 11 incentivised diseases. This provided 68,991 observations, representing a total of 15 million opportunities for exception reporting. Across all observations, the median overall exception reporting rate was 7.0% (7.04% in 2010-2011; 7.02% in 2011-2012 and 6.92% in 2012-2013). The median non-attendance rate due to ID was 0.9% (0.76% in 2010-2011; 0.88% in 2011-2012 and 0.96% in 2012-2013). Median population achievement was 83.5% (83.51% in 2010-2011; 83.41% in 2011-2012 and 83.63% in 2012-2013). The odds of ID reporting in 2012/2013 were 16.0% greater than in 2010/2011 (p < 0.001). Practices in Scotland's most deprived communities were twice as likely to report non-attendance due to ID (odds ratio 2.10, 95% confidence interval 1.83-2.40, p < 0.001) compared with those in the least deprived; rural practices reported lower levels of non-attendance due to ID. These predictors were also independently associated with overall exceptions. Rates of population achievement did not change over time, with higher levels (higher remuneration) associated with increased rates of overall and ID exception and more affluent practices. Non-attendance for CDM due to ID has risen over time, and higher rates are seen in patients from practices located in disadvantaged areas. This suggests that CDM incentivisation does not conform to the inverse equity hypothesis, because inequalities are widening over time with lower uptake of anticipatory care health checks and CDM reviews noted among those most in need. Incentivised CDM needs to include incentives for engaging with the 'hard to reach' if inequalities in healthcare delivery are to be tackled.

Substance abuse and quality of life among severely mentally ill consumers: a longitudinal modelling analysis.

PubMed

Urbanoski, Karen A; Cairney, John; Adlaf, Edward; Rush, Brian

2007-10-01

Evidence suggests that substance abuse negatively affects both psychiatric symptom severity and quality of life (QOL) in people with severe mental illness (SMI). However, these relationships have not been examined simultaneously, nor have they been characterized over time. Thus, it is difficult to appreciate the extent to which substance abuse exerts an enduring effect on psychiatric symptoms and distress and/or QOL in this population. The purpose of this study is to test a conceptual model linking these factors together. Subjects were participants in a longitudinal evaluation of community mental healthcare in Ontario (n = 133). Comprehensive consumer assessments were conducted at treatment entry, and at 9 and 18 months. Subjects were receiving intensive case management or assertive community treatment throughout the 18-month study period. Structural equation modelling was used to examine the concurrent and longitudinal relationships between substance abuse, symptoms and distress, and QOL. The prevalence of substance abuse was 55.0%. The SEM analysis suggested that substance abuse at baseline was associated with elevated symptomatology and distress and lower QOL, and that these effects endured after 18 months of treatment. Psychiatric symptoms and distress mediated the negative relationship between substance abuse and QOL. The mediating role played by symptom and distress levels in the relationship between substance abuse and QOL suggests the importance of closely monitoring changes in these factors among SMI patients with substance problems. Tracking symptom severity and distress levels over time will allow service providers to intervene and potentially improve the QOL of individuals with SMI.

Longitudinal genomic surveillance of Plasmodium falciparum malaria parasites reveals complex genomic architecture of emerging artemisinin resistance.

PubMed

Cerqueira, Gustavo C; Cheeseman, Ian H; Schaffner, Steve F; Nair, Shalini; McDew-White, Marina; Phyo, Aung Pyae; Ashley, Elizabeth A; Melnikov, Alexandre; Rogov, Peter; Birren, Bruce W; Nosten, François; Anderson, Timothy J C; Neafsey, Daniel E

2017-04-28

Artemisinin-based combination therapies are the first line of treatment for Plasmodium falciparum infections worldwide, but artemisinin resistance has risen rapidly in Southeast Asia over the past decade. Mutations in the kelch13 gene have been implicated in this resistance. We used longitudinal genomic surveillance to detect signals in kelch13 and other loci that contribute to artemisinin or partner drug resistance. We retrospectively sequenced the genomes of 194 P. falciparum isolates from five sites in Northwest Thailand, over the period of a rapid increase in the emergence of artemisinin resistance (2001-2014). We evaluate statistical metrics for temporal change in the frequency of individual SNPs, assuming that SNPs associated with resistance increase in frequency over this period. After Kelch13-C580Y, the strongest temporal change is seen at a SNP in phosphatidylinositol 4-kinase, which is involved in a pathway recently implicated in artemisinin resistance. Furthermore, other loci exhibit strong temporal signatures which warrant further investigation for involvement in artemisinin resistance evolution. Through genome-wide association analysis we identify a variant in a kelch domain-containing gene on chromosome 10 that may epistatically modulate artemisinin resistance. This analysis demonstrates the potential of a longitudinal genomic surveillance approach to detect resistance-associated gene loci to improve our mechanistic understanding of how resistance develops. Evidence for additional genomic regions outside of the kelch13 locus associated with artemisinin-resistant parasites may yield new molecular markers for resistance surveillance, which may be useful in efforts to reduce the emergence or spread of artemisinin resistance in African parasite populations.

A longitudinal analysis of the influence of the neighborhood built environment on walking for transportation: the RESIDE study.

PubMed

Knuiman, Matthew W; Christian, Hayley E; Divitini, Mark L; Foster, Sarah A; Bull, Fiona C; Badland, Hannah M; Giles-Corti, Billie

2014-09-01

The purpose of the present analysis was to use longitudinal data collected over 7 years (from 4 surveys) in the Residential Environments (RESIDE) Study (Perth, Australia, 2003-2012) to more carefully examine the relationship of neighborhood walkability and destination accessibility with walking for transportation that has been seen in many cross-sectional studies. We compared effect estimates from 3 types of logistic regression models: 2 that utilize all available data (a population marginal model and a subject-level mixed model) and a third subject-level conditional model that exclusively uses within-person longitudinal evidence. The results support the evidence that neighborhood walkability (especially land-use mix and street connectivity), local access to public transit stops, and variety in the types of local destinations are important determinants of walking for transportation. The similarity of subject-level effect estimates from logistic mixed models and those from conditional logistic models indicates that there is little or no bias from uncontrolled time-constant residential preference (self-selection) factors; however, confounding by uncontrolled time-varying factors, such as health status, remains a possibility. These findings provide policy makers and urban planners with further evidence that certain features of the built environment may be important in the design of neighborhoods to increase walking for transportation and meet the health needs of residents. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Longitudinal evaluation of leukocyte transcripts in killer whales (Orcinus Orca)

USGS Publications Warehouse

Sitt, Tatjana; Bowen, Lizabeth; Lee, Chia-Shan; Blanchard, Myra; McBain, James; Dold, Christopher; Stott, Jeffrey L.

2016-01-01

Early identification of illness and/or presence of environmental and/or social stressors in free-ranging and domestic cetaceans is a priority for marine mammal health care professionals. Incorporation of leukocyte gene transcript analysis into the diagnostic tool kit has the potential to augment classical diagnostics based upon ease of sample storage and shipment, inducible nature and well-defined roles of transcription and associated downstream actions. Development of biomarkers that could serve to identify “insults” and potentially differentiate disease etiology would be of great diagnostic value. To this end, a modest number of peripheral blood leukocyte gene transcripts were selected for application to a domestic killer whale population with a focus on broad representation of inducible immunologically relevant genes. Normalized leukocyte transcript values, longitudinally acquired from 232 blood samples derived from 26 clinically healthy whales, were not visibly influenced temporally nor by sex or the specific Park in which they resided. Stability in leukocyte transcript number during periods of health enhances their potential use in diagnostics through identification of outliers. Transcript levels of two cytokine genes, IL-4 and IL-17, were highly variable within the group as compared to the other transcripts. IL-4 transcripts were typically absent. Analysis of transcript levels on the other genes of interest, on an individual animal basis, identified more outliers than were visible when analyzed in the context of the entire population. The majority of outliers (9 samples) were low, though elevated transcripts were identified for IL-17 from 2 animals and one each for Cox-2 and IL-10. The low number of outliers was not unexpected as sample selection was intentionally directed towards animals that were clinically healthy at the time of collection. Outliers may reflect animals experiencing subclinical disease that is transient and self-limiting. The immunologic knowledge derived from longitudinal immunologic studies in killer whales, as was the target of the present study, has the potential to improve diagnostics and health related decision making for this and other domestic and free-ranging cetacean species.

Longitudinal evaluation of leukocyte transcripts in killer whales (Orcinus Orca).

PubMed

Sitt, Tatjana; Bowen, Lizabeth; Lee, Chia-Shan; Blanchard, Myra T; McBain, James; Dold, Christopher; Stott, Jeffrey L

2016-07-01

Early identification of illness and/or presence of environmental and/or social stressors in free-ranging and domestic cetaceans is a priority for marine mammal health care professionals. Incorporation of leukocyte gene transcript analysis into the diagnostic tool kit has the potential to augment classical diagnostics based upon ease of sample storage and shipment, inducible nature and well-defined roles of transcription and associated downstream actions. Development of biomarkers that could serve to identify "insults" and potentially differentiate disease etiology would be of great diagnostic value. To this end, a modest number of peripheral blood leukocyte gene transcripts were selected for application to a domestic killer whale population with a focus on broad representation of inducible immunologically relevant genes. Normalized leukocyte transcript values, longitudinally acquired from 232 blood samples derived from 26 clinically healthy whales, were not visibly influenced temporally nor by sex or the specific Park in which they resided. Stability in leukocyte transcript number during periods of health enhances their potential use in diagnostics through identification of outliers. Transcript levels of two cytokine genes, IL-4 and IL-17, were highly variable within the group as compared to the other transcripts. IL-4 transcripts were typically absent. Analysis of transcript levels on the other genes of interest, on an individual animal basis, identified more outliers than were visible when analyzed in the context of the entire population. The majority of outliers (9 samples) were low, though elevated transcripts were identified for IL-17 from 2 animals and one each for Cox-2 and IL-10. The low number of outliers was not unexpected as sample selection was intentionally directed towards animals that were clinically healthy at the time of collection. Outliers may reflect animals experiencing subclinical disease that is transient and self-limiting. The immunologic knowledge derived from longitudinal immunologic studies in killer whales, as was the target of the present study, has the potential to improve diagnostics and health related decision making for this and other domestic and free-ranging cetacean species. Copyright © 2016. Published by Elsevier B.V.

The relation between pathological worrying and fatigue in a working population.

PubMed

Andrea, H; Beurskens, A J H M; Kant, Ij; Davey, G C L; Field, A P; van Schayck, C P

2004-10-01

This study aimed to explore cross-sectional and longitudinal associations between pathological worry and fatigue in a working population. In employees with very low or very high fatigue levels, psychometrics of the Penn State Worry Questionnaire (PSWQ; measuring pathological worry) and the Checklist Individual Strength (CIS; measuring fatigue) were examined and their cross-sectional and longitudinal associations were explored. Pathological worry and fatigue can be measured as different constructs. However, pathological worry and fatigue were also associated on a cross-sectional level. Pathological worry predicted fatigue level 10 months later, but this association disappeared after adjustment for the cross-sectional association between pathological worry and fatigue. Although they can be measured as different constructs, pathological worry and fatigue seem to be associated. When studying longitudinal relations between pathological worry and fatigue, their cross-sectional association should be taken into account. Pathological worry might not be a risk factor for fatigue per se, but might act more like a mediating factor.

Longitudinal density monitor for the LHC

NASA Astrophysics Data System (ADS)

Jeff, A.; Andersen, M.; Boccardi, A.; Bozyigit, S.; Bravin, E.; Lefevre, T.; Rabiller, A.; Roncarolo, F.; Welsch, C. P.; Fisher, A. S.

2012-03-01

The longitudinal density monitor (LDM) is primarily intended for the measurement of the particle population in nominally empty rf buckets. These so-called satellite or ghost bunches can cause problems for machine protection as well as influencing the luminosity calibration of the LHC. The high dynamic range of the system allows measurement of ghost bunches with as little as 0.01% of the main bunch population at the same time as characterization of the main bunches. The LDM is a single-photon counting system using visible synchrotron light. The photon detector is a silicon avalanche photodiode operated in Geiger mode, which allows the longitudinal distribution of the LHC beams to be measured with a resolution of 90 ps. Results from the LDM are presented, including a proposed method for constructing a 3-dimensional beam density map by scanning the LDM sensor in the transverse plane. In addition, we present a scheme to improve the sensitivity of the system by using an optical switching technique.

Evolution and Determinants of Health-Related Quality-of-Life in Kidney Transplant Patients Over the First 3 Years After Transplantation.

PubMed

Villeneuve, Claire; Laroche, Marie-Laure; Essig, Marie; Merville, Pierre; Kamar, Nassim; Coubret, Anne; Lacroix, Isabelle; Bouchet, Stéphane; Fruit, Dorothée; Marquet, Pierre; Rousseau, Annick

2016-03-01

Health-related quality of life (HRQOL) usually improved after kidney transplantation; however, a non-negligible number of patients did not benefit from transplantation in HRQOL. The aims of this cohort study were to describe the evolution of HRQOL in kidney transplant recipients to search for subgroups with distinct time profiles and to investigate these determinants. Three hundred thirty-seven adult patients were followed up from 1 to 36 months after kidney transplantation. Each patient completed repeated HRQOL assessments (median, 5; range, 2-9). K-means for longitudinal data was used to identify homogeneous clusters of HRQOL time profiles obtained for the mental and physical composite scores (MCS and PCS) and for the 8 dimensions of the short-form 36 scale. Covariates associated with these clusters were investigated using random forest analysis. Magnitude and shape of the HRQOL variations over time were investigated using linear regression mixed models. Two longitudinal clusters were identified for the time profiles of PCS and MCS. Patients classified in the higher cluster (ie, 60% of the population) exhibited a steady-state HRQOL, similar on average to the general population, whereas in the lower cluster, PCS and MCS scores were significantly lower than in the general population. Muscular weakness in the first year after transplantation explained 19% of the interpatient variability of PCS 3 months after transplantation, whereas associated with anxiety, it explained 24% of interpatient MCS variability. This work suggests to promote (i) physical rehabilitation programs after transplantation to curb the muscular loss and (ii) systematic attention to the patient's anxiety.

The Relationship of Housing and Population Health: A 30-Year Retrospective Analysis

PubMed Central

Jacobs, David E.; Wilson, Jonathan; Dixon, Sherry L.; Smith, Janet; Evens, Anne

2009-01-01

Objective We analyzed the relationship between health status and housing quality over time. Methods We combined data from two nationally representative longitudinal surveys of the U.S. population and its housing, the National Health and Nutrition Examination Survey and the American Housing Survey, respectively. We identified housing and health trends from approximately 1970 to 2000, after excluding those trends for which data were missing or where we found no plausible association or change in trend. Results Changes in housing include construction type, proportion of rental versus home ownership, age, density, size, moisture, pests, broken windows, ventilation and air conditioning, and water leaks. Changes in health measures include asthma, respiratory illness, obesity and diabetes, and lead poisoning, among others. The results suggest ecologic trends in childhood lead poisoning follow housing age, water leaks, and ventilation; asthma follows ventilation, windows, and age; overweight trends follow ventilation; blood pressure trends follow community measures; and health disparities have not changed greatly. Conclusions Housing trends are consistent with certain health trends over time. Future national longitudinal surveys should include health, housing, and community metrics within a single integrated design, instead of separate surveys, in order to develop reliable indicators of how housing changes affect population health and how to best target resources. Little progress has been made in reducing the health and housing disparities of disadvantaged groups, with the notable exception of childhood lead poisoning caused by exposure to lead-based paint hazards. Use of these and other data sets to create reliable integrated indicators of health and housing quality are needed. PMID:19440499

Does Helicobacter pylori infection increase incidence of dementia? The Personnes Agées QUID Study.

PubMed

Roubaud Baudron, Claire; Letenneur, Luc; Langlais, Anthony; Buissonnière, Alice; Mégraud, Francis; Dartigues, Jean-François; Salles, Nathalie

2013-01-01

To determine whether Helicobacter pylori infection was associated with dementia and risk of developing dementia in a longitudinal population-based cohort of elderly adults living in the community. Prospective community-based cohort study. The population-based Personnes Agées QUID (PAQUID) Study. Six hundred three noninstitutionalized individuals aged 65 and older living in the southwest of France followed from 1989 to 2008. A descriptive and comparative analysis including dementia prevalence, according to H. pylori status (serology), was made at baseline. Cox proportional hazard models were used to study the risk of developing dementia according to H. pylori status assessed on sera samples from elderly adults initially free of dementia and followed for 20 years. A neurologist diagnosed dementia according to Diagnostic and Statistical Manual of Mental Disorders Third Edition criteria. At baseline, 391 (64.8%) subjects (348 women, mean age 73.9 ± 6.5) were seropositive for H. pylori. Dementia prevalence was higher in the infected group (5.4% vs 1.4%, P = .02). After 20 years of follow-up, 148 incident cases of dementia were diagnosed. After controlling for age, sex, educational level, apolipoprotein E4 status, cardiovascular risk factors, and Mini-Mental State Examination score, H. pylori infection was determined to be a risk factor for developing dementia (hazard ratio = 1.46, P = .04). This longitudinal population-based study provides additional epidemiological support to the hypothesis of an association between dementia and H. pylori infection, which may enhance neurodegeneration. © 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.

The influence of unmet supportive care needs on anxiety and depression during cancer treatment and beyond: a longitudinal study of survivors of haematological cancers.

PubMed

Oberoi, Devesh; White, Victoria M; Seymour, John F; Miles Prince, H; Harrison, Simon; Jefford, Michael; Winship, Ingrid; Hill, David; Bolton, Damien; Kay, Anne; Millar, Jeremy; Doo, Nicole Wong; Giles, Graham

2017-11-01

This paper aims to examine the cross-sectional and longitudinal associations between patient-reported unmet needs and anxiety and depression for survivors of diffuse large B cell lymphoma (DLBCL) and multiple myeloma (MM). In a longitudinal study design, self-reported data were collected through telephone interviews at two time points approximately 7 (T1) and 15 (T2) months post-diagnosis. The sample was recruited through the population-based Victorian Cancer Registry. At T1 and T2, the study outcomes, anxiety and depression, were assessed using the Hospital Anxiety and Depression Scale (HADS) and unmet needs were measured using the Supportive Care Needs Survey (SCNS-SF34). Questions related to social/family problems, relationship problems and financial problems were also asked. A three-step multivariable hierarchical logistic regression analysis examined the relative role of T1 anxiety and depression, T1 and T2 unmet needs and other psychosocial factors with T2 anxiety and depression. Both cross-sectional and longitudinal associations were observed between unmet needs and psychological distress. T2 anxiety was associated with T1 anxiety (OR 4.75, 95% CI 1.86-11.09), T2 psychological needs (OR 1.68, 95% CI 1.34-2.11) and with T1 social problems (OR 2.33, 95% CI 1.03-5.05) in multivariate analysis. T2 depression was associated with both T1 (OR 1.28, 95% CI 1.06-1.57) and T2 psychological needs (OR 1.35, 95% CI 1.06-1.70), T2 physical needs (OR 1.89, 95% CI 1.27-2.81) and T1 depression (OR 4.52, 95% CI 1.88-10.86). Unmet needs that manifest following diagnosis and treatment may persist into early survivorship and contribute to psychological distress. Addressing these needs during treatment may diminish the risk of current and future anxiety and depression.

The Adopted Adolescent. Selected Papers Number 55.

ERIC Educational Resources Information Center

Banning, Anne

This review of studies on clinical and nonclinical populations explores outcomes of adoption and developmental issues for adolescents, and in particular, developmental problems for adopted adolescents. Studies on nonclinical populations demonstrate that adoption is a highly successful form of substitute care. Prospective longitudinal studies show…

An empirical analysis of the public's attitudes toward advertising hospital services: a comparative cross-sectional study.

PubMed

Moser, H Ronald; Freeman, Gordon L

2014-01-01

This study investigates current opinions about hospital advertising and compares them to the attitudes expressed 25 years ago. It replicates a survey done in 1985, using the same questionnaire and population to compare responses longitudinally. The study indicates some changes in the public's opinions of hospital advertising. Although the image of hospitals remains positive, most of the 2010 respondents' opinions were rather mixed regarding whether it is proper for hospitals to advertise. The study also confirmed that the quality of service and reputation of hospitals remain more important to the public than price.

Impulsive Behavior and Associated Clinical Variables in Parkinson's Disease

PubMed Central

Abosch, Aviva; Gupte, Akshay; Eberly, Lynn E.; Tuite, Paul J.; Nance, Martha; Grant, Jon E.

2011-01-01

Parkinson's disease (PD) is a degenerative brain disorder accompanied by the loss of dopaminergic neurons and the presence of motor and non-motor symptoms. We performed a cross-sectional, questionnaire-based analysis of impulsive behavior in our PD clinic population to assess prevalence and associated characteristics. We found a higher prevalence of impulsive behavior (29.7%) than previously reported, and found multiple, concurrent impulsive behaviors in 26% of subjects reporting impulsive behavior. Our findings contribute to the growing awareness of impulsive behavior in PD, and support the need for longitudinal studies to assess changes in impulsive behaviors in Parkinson's patients. PMID:21300194

Genomic Consequences of Population Decline in the Endangered Florida Scrub-Jay.

PubMed

Chen, Nancy; Cosgrove, Elissa J; Bowman, Reed; Fitzpatrick, John W; Clark, Andrew G

2016-11-07

Understanding the population genetic consequences of declining population size is important for conserving the many species worldwide facing severe decline [1]. Thorough empirical studies on the impacts of population reduction at a genome-wide scale in the wild are scarce because they demand huge field and laboratory investments [1, 2]. Previous studies have demonstrated the importance of gene flow in introducing genetic variation to small populations [3], but few have documented both genetic and fitness consequences of decreased immigration through time in a natural population [4-6]. Here we assess temporal variation in gene flow, inbreeding, and fitness using longitudinal genomic, demographic, and phenotypic data from a long-studied population of federally Threatened Florida scrub-jays (Aphelocoma coerulescens). We exhaustively sampled and genotyped the study population over two decades, providing one of the most detailed longitudinal investigations of genetics in a wild animal population to date. Immigrants were less heterozygous than residents but still introduced genetic variation into our study population. Owing to regional population declines, immigration into the study population declined from 1995-2013, resulting in increased levels of inbreeding and reduced fitness via inbreeding depression, even as the population remained demographically stable. Our results show that, contrary to conventional wisdom, small peripheral populations that already have undergone a genetic bottleneck may play a vital role in preserving genetic diversity of larger and seemingly stable populations. These findings underscore the importance of investing in the persistence of small populations and maintaining population connectivity in conservation of fragmented species. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bayesian Covariate Selection in Mixed-Effects Models For Longitudinal Shape Analysis

PubMed Central

Muralidharan, Prasanna; Fishbaugh, James; Kim, Eun Young; Johnson, Hans J.; Paulsen, Jane S.; Gerig, Guido; Fletcher, P. Thomas

2016-01-01

The goal of longitudinal shape analysis is to understand how anatomical shape changes over time, in response to biological processes, including growth, aging, or disease. In many imaging studies, it is also critical to understand how these shape changes are affected by other factors, such as sex, disease diagnosis, IQ, etc. Current approaches to longitudinal shape analysis have focused on modeling age-related shape changes, but have not included the ability to handle covariates. In this paper, we present a novel Bayesian mixed-effects shape model that incorporates simultaneous relationships between longitudinal shape data and multiple predictors or covariates to the model. Moreover, we place an Automatic Relevance Determination (ARD) prior on the parameters, that lets us automatically select which covariates are most relevant to the model based on observed data. We evaluate our proposed model and inference procedure on a longitudinal study of Huntington's disease from PREDICT-HD. We first show the utility of the ARD prior for model selection in a univariate modeling of striatal volume, and next we apply the full high-dimensional longitudinal shape model to putamen shapes. PMID:28090246

Volunteering and older women: psychosocial and health predictors of participation.

PubMed

Parkinson, Lynne; Warburton, Jeni; Sibbritt, David; Byles, Julie

2010-11-01

As populations age, there will be a need for more volunteers in social welfare, and consequently a need to better understand potential effects of volunteering for older people. Whilst there is a body of international literature exploring health benefits of volunteering in later life, there are currently no longitudinal studies of Australian populations. Internationally, there is a lack of studies focusing on older women, who comprise the majority of the ageing population. The aim of this article was to explore the relationship between volunteering and psychosocial and health factors for a cohort of older Australian women over time. Data for this study were from the oldest cohort of Australian Longitudinal Study on Women's Health, a 20-year longitudinal survey of Australian women aged 70-75 years in 1996. Volunteering status was the factor of interest and study factors included a broad range of demographic, health and social factors. A longitudinal model was developed for mediators of volunteering over time. Of 7088 women in 2005, 24.5% reported actively volunteering, 15.5% were continuing, 7.5% were new, 15.3% were intermittent and 34.7% had never been volunteers. Volunteering was associated with increased quality of life and social support. Women were more likely to continue volunteering over time if they lived in a rural area, had higher socioeconomic indicators, and better levels of physical and mental health. This study contributes to the literature on the relationship between volunteering and health for older women. Understanding the potential health implications of volunteering is a critical issue in current policy debates.

C-reactive protein, APOE genotype and longitudinal cognitive change in an older population

PubMed Central

Lima, Thomas A. S.; Adler, Amanda L.; Minett, Thais; Matthews, Fiona E.; Brayne, Carol; Marioni, Riccardo E.

2014-01-01

Background: circulating measures of inflammatory markers, such as C-reactive protein (CRP) have been associated with an increased risk of future cognitive decline. However, the nature of the relationship among the very old (>75 years) is unclear. Cross-sectional evidence suggests that elevated CRP may even be protective in this age group. This study examines these associations longitudinally. Methods: logistic regression was used to investigate the association between CRP and drop in cognitive performance (≥3 point change on the Mini-Mental State Examination) over a 4-year period in a population of 266 people, mean age 77 years. Results: increased levels of CRP were associated with a decreased risk of a drop in cognitive performance; however, this association was only seen in those without an APOE e4 allele [odds ratio of decline per unit increase in ln(CRP) 0.57, P = 0.04]. The magnitude of the finding remained consistent after adjustment for cardiovascular confounders (smoking, drinking, MI, stroke, diabetes, education, medication and blood pressure). For those with an e4 allele, the relationship with longitudinal cognitive decline was neither statistically significant nor in a consistent direction after controlling for acute inflammation. Conclusions: this study strengthens previous cross-sectional findings and shows elevated levels of CRP to be linked to a decreased risk of longitudinal cognitive decline in the very old. However, as with prior analyses, this was only observed in those not carrying an APOE e4 allele. Future work on larger APOE e4 allele carrying samples is required to determine the nature of the association in this population. PMID:24305621

Obsessive-Compulsive Disorder, Psychosis, and Bipolarity: A Longitudinal Cohort and Multigenerational Family Study

PubMed Central

Cederlöf, Martin; Lichtenstein, Paul; Larsson, Henrik; Boman, Marcus; Rück, Christian; Landén, Mikael; Mataix-Cols, David

2015-01-01

Obsessive-compulsive disorder (OCD) often co-occurs with psychotic and bipolar disorders; this comorbidity complicates the clinical management of these conditions. In this population-based longitudinal and multigenerational family study, we examined the patterns of comorbidity, longitudinal risks, and shared familial risks between these disorders. Participants were individuals with a diagnosis of OCD (n = 19814), schizophrenia (n = 58336), bipolar disorder (n = 48180), and schizoaffective disorder (n = 14904) included in the Swedish Patient Register between January 1969 and December 2009; their first-, second-, and third-degree relatives; and population-matched (1:10 ratio) unaffected comparison individuals and their relatives. The Swedish Prescribed Drug Register was used to control for the potential effect of medication in the longitudinal analyses. Individuals with OCD had a 12-fold increased risk of having a comorbid diagnosis of schizophrenia and a 13-fold increased risk of bipolar disorder and schizoaffective disorder. Longitudinal analyses showed that individuals first diagnosed with OCD had an increased risk for later diagnosis of all other disorders, and vice versa. The risk of bipolar disorder was reduced, but not eliminated, when the use of selective serotonin reuptake inhibitors was adjusted for. OCD-unaffected first-, second-, and third-degree relatives of probands with OCD had a significantly increased risk for all 3 disorders; the magnitude of this risk decreased as the genetic distance increased. We conclude that OCD is etiologically related to both schizophrenia spectrum and bipolar disorders. The results have implications for current gene-searching efforts and for clinical practice. PMID:25512596

A mechanical analysis of conduit arteries accounting for longitudinal residual strains.

PubMed

Wang, Ruoya; Gleason, Rudolph L

2010-04-01

Identification of an appropriate stress-free reference configuration is critically important in providing a reasonable prediction of the intramural stress distribution when performing biomechanical analyses on arteries. The stress-free state is commonly approximated as a radially cut ring that typically opens into a nearly circular sector, relieving much of the circumferential residual strains that exist in the traction-free configuration. An opening angle is often used to characterize this sector. In this study, we first present experimental results showing significant residual deformations in the longitudinal direction of two commonly studied arteries in the pig: the common carotid artery and the left anterior descending coronary artery. We concluded that a radially cut ring cannot completely describe the stress-free state of the arteries. Instead, we propose the use of a longitudinal opening angle, in conjunction with the traditional circumferential opening angle, to experimentally quantify the stress-free state of an artery. Secondly, we propose a new kinematic model to account for the addition of longitudinal residual strains through employing the longitudinal opening angle and performed a stress analysis. We found that with the inclusion of longitudinal residual strains in the stress analysis, the predicted circumferential stress gradient was decreased by 3-fold and the predicted longitudinal stress gradient was increased by 5.7-fold. Thus, inclusion of longitudinal residual strains has a significant effect on the predicted stress distribution in arteries.

A Longitudinal Approach to Great Plains Migration

ERIC Educational Resources Information Center

Hudson, John C.

2002-01-01

Students of population and regional studies are familiar with the demographic accounting equation in which the size of the population at time t + x is equal to the population at time t plus the births, minus the deaths, plus the immigrants, minus the emigrants, during the interval of time x. This simple formula can be used to derive a variety of…

Sleep disturbance and longitudinal risk of inflammation: Moderating influences of social integration and social isolation in the Coronary Artery Risk Development in Young Adults (CARDIA) study.

PubMed

Cho, Hyong Jin; Seeman, Teresa E; Kiefe, Catarina I; Lauderdale, Diane S; Irwin, Michael R

2015-05-01

Both sleep disturbance and social isolation increase the risk for morbidity and mortality. Systemic inflammation is suspected as a potential mechanism of these associations. However, the complex relationships between sleep disturbance, social isolation, and inflammation have not been examined in a population-based longitudinal study. This study examined the longitudinal association between sleep disturbance and systemic inflammation, and the moderating effects of social isolation on this association. The CARDIA study is a population-based longitudinal study conducted in four US cities. Sleep disturbance - i.e., insomnia complaints and short sleep duration - was assessed in 2962 African-American and White adults at baseline (2000-2001, ages 33-45years). Circulating C-reactive protein (CRP) was measured at baseline and follow-up (2005-2006). Interleukin-6 (IL-6) and subjective and objective social isolation (i.e., feelings of social isolation and social network size) were measured at follow-up. Sleep disturbance was a significant predictor of inflammation five years later after full adjustment for covariates (adjusted betas: 0.048, P=0.012 for CRP; 0.047, P=0.017 for IL-6). Further adjustment for baseline CRP revealed that sleep disturbance also impacted the longitudinal change in CRP levels over five years (adjusted beta: 0.044, P=0.013). Subjective social isolation was a significant moderator of this association between sleep disturbance and CRP (adjusted beta 0.131, P=0.002). Sleep disturbance was associated with heightened systemic inflammation in a general population over a five-year follow-up, and this association was significantly stronger in those who reported feelings of social isolation. Clinical interventions targeting sleep disturbances may be a potential avenue for reducing inflammation, particularly in individuals who feel socially isolated. Copyright © 2015 Elsevier Inc. All rights reserved.

Longitudinal monitoring of bottlenose dolphins leukocyte cytokine mRNA responsiveness by qPCR

USDA-ARS?s Scientific Manuscript database

Both veterinarians caring for bottlenose dolphins (Tursiops truncatus) in managed populations and researchers monitoring wild populations use blood-based diagnostics to monitor bottlenose dolphin health. Quantitative PCR (qPCR) can be used to assess cytokine expression patterns of peripheral blood m...

Longitudinal monitoring of bottlenose dolphin leukocyte cytokine mRNA responsiveness by qPCR

USDA-ARS?s Scientific Manuscript database

Both veterinarians caring for bottlenose dolphins (Tursiops truncatus) in managed populations and researchers monitoring wild populations use blood-based diagnostics to monitor bottlenose dolphin health. Quantitative PCR (qPCR) can be used to assess cytokine expression patterns of peripheral blood m...

Improved Cognitive Development in Preterm Infants with Shared Book Reading.

PubMed

Braid, Susan; Bernstein, Jenny

2015-01-01

To examine the effect of shared book reading on the cognitive development of children born preterm and to determine what factors influence shared book reading in this population. Secondary analysis using the Early Childhood Longitudinal Study-Birth Cohort, a large, nationally representative survey of children born in the United States in 2001. One thousand four hundred singleton preterm infants (22-36 weeks gestation). Cognitive development measured using the Bayley Mental Scale score from the Bayley Scales of Infant Development Research Edition. Adjusting for neonatal, maternal, and socioeconomic characteristics, reading aloud more than two times a week is associated with higher cognitive development scores in two-year-old children born preterm (p < .001). Race/ethnicity and maternal education affect how often parents read to their children. Shared book reading holds potential as an early developmental intervention for this population.

Six-year changes in refraction and related ocular biometric factors in an adult Chinese population.

PubMed

Han, Xiaotong; Guo, Xinxing; Lee, Pei Ying; Morgan, Ian G; He, Mingguang

2017-01-01

To investigate longitudinal changes in refraction and biometry in Chinese adults. Population-based prospective cohort study. 1817 subjects aged ≥ 35 years were randomly recruited from Yuexiu district, Guangzhou, China in 2008. Of which 1595 (87.8%) were reexamined in 2010 and 1427 (78.5%) were reexamined in 2014. Non-cycloplegic automated refraction and visual acuity test were performed at baseline and the 6-year follow-up examination for all participants. In addition, 50% of the participants were randomly selected for axial length (AL), anterior chamber depth (ACD) and lens thickness (LT) measurements using non-contact partial coherence laser interferometry. Lens power (LP) was calculated with the Bennett's equation. A total of 1300 participants were included in current analysis (2008 mean [SD] age, 51.4 [10.6] years; 54.5% women). Mean change in spherical equivalence (SE) was +0.24 (95% confidence interval [CI], +0.19 to +0.30), +0.51 (95% CI, +0.46 to +0.57), +0.26 (95% CI, +0.15 to +0.38) and -0.05 (95% CI, -0.21 to +0.10) diopters (D) for individuals in the age groups of 35 to 44, 45 to 54, 55 to 64 and 65+ years at baseline, respectively. Corneal power, AL and LT increased while ACD and LP decreased during the follow-up. Baseline SE and changes in biometric factors could explain 97.2% of the variance in longitudinal SE change while LP solely could explain 65.2%. Six-year mean change in cylinder power was -0.16 (95% CI, -0.19 to -0.13) D, the axis of astigmatism changed from "with-the-rule" to "against-the-rule" in 16.4% of the participants and to "oblique" in 0.9%. This study confirms a hyperopic shift in the elderly before 65 years old and a myopic shift thereafter. Longitudinal refraction change could be well explained by corresponding biometry changes, especially LP. There is also a shift to "against-the-rule" astigmatism for the adult population.

Risk factor modifications and depression incidence: a 4-year longitudinal Canadian cohort of the Montreal Catchment Area Study.

PubMed

Meng, Xiangfei; Brunet, Alain; Turecki, Gustavo; Liu, Aihua; D'Arcy, Carl; Caron, Jean

2017-06-10

Few studies have examined the effect of risk factor modifications on depression incidence. This study was to explore psychosocial risk factors for depression and quantify the effect of risk factor modifications on depression incidence in a large-scale, longitudinal population-based study. Data were from the Montreal Longitudinal Catchment Area study (N=2433). Multivariate modified Poisson regression was used to estimate relative risk (RR). Population attributable fractions were also used to estimate the potential impact of risk factor modifications on depression incidence. The cumulative incidence rate of major depressive disorder at the 2-year follow-up was 4.8%, and 6.6% at the 4-year follow-up. Being a younger adult, female, widowed, separated or divorced, Caucasian, poor, occasional drinker, having a family history of mental health problems, having less education and living in areas with higher unemployment rates and higher proportions of visible minorities, more cultural community centres and community organisations, were consistently associated with the increased risk of incident major depressive disorder. Although only 5.1% of the disease incidence was potentially attributable to occasional drinking (vs abstainers) at the 2-year follow-up, the attribution of occasional drinking doubled at the 4-year follow-up. A 10% reduction in the prevalence of occasional drinking in this population could potentially prevent half of incident cases. Modifiable risk factors, both individual and societal, could be the targets for public depression prevention programmes. These programmes should also be gender-specific, as different risk factors have been identified for men and women. Public health preventions at individual levels could focus on the better management of occasional drinking, as it explained around 5%~10% of incident major depressive disorders. Neighbourhood characteristics could also be the target for public prevention programmes. However, this could be very challenging. A cost-effectiveness analysis of a variety of prevention efforts is warranted. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A Longitudinal Analysis of Mosquito Net Ownership and Use in an Indigenous Batwa Population after a Targeted Distribution

PubMed Central

Clark, Sierra; Berrang-Ford, Lea; Lwasa, Shuaib; Namanya, Didacus; Twesigomwe, Sabastian; Kulkarni, Manisha

2016-01-01

Major efforts for malaria prevention programs have gone into scaling up ownership and use of insecticidal mosquito nets, particularly in sub-Saharan Africa where the malaria burden is high. Socioeconomic inequities in access to long lasting insecticidal nets (LLINs) are reduced with free distributions of nets. However, the relationship between social factors and retention of nets after a free distribution has been less studied, particularly using a longitudinal approach. Our research aimed to estimate the ownership and use of LLINs, and examine the determinants of LLIN retention, within an Indigenous Batwa population after a free LLIN distribution. Two LLINs were given free of charge to each Batwa household in Kanungu District, Uganda in November 2012. Surveyors collected data on LLIN ownership and use through six cross-sectional surveys pre- and post-distribution. Household retention, within household access, and individual use of LLINs were assessed over an 18-month period. Socioeconomic determinants of household retention of LLINs post-distribution were modelled longitudinally using logistic regression with random effects. Direct house-to-house distribution of free LLINs did not result in sustainable increases in the ownership and use of LLINs. Three months post-distribution, only 73% of households owned at least one LLIN and this period also saw the greatest reduction in ownership compared to other study periods. Eighteen-months post distribution, only a third of households still owned a LLIN. Self-reported age-specific use of LLINs was generally higher for children under five, declined for children aged 6–12, and was highest for older adults aged over 35. In the model, household wealth was a significant predictor of LLIN retention, controlling for time and other variables. This research highlights on-going socioeconomic inequities in access to malaria prevention measures among the Batwa in southwestern Uganda, even after free distribution of LLINs, and provides critical information to inform local malaria programs on possible intervention entry-points to increase access and use among this marginalized population. PMID:27145034

Six-year changes in refraction and related ocular biometric factors in an adult Chinese population

PubMed Central

Han, Xiaotong; Guo, Xinxing; Lee, Pei Ying; Morgan, Ian G.; He, Mingguang

2017-01-01

Purpose To investigate longitudinal changes in refraction and biometry in Chinese adults. Design Population-based prospective cohort study. Methods 1817 subjects aged ≥ 35 years were randomly recruited from Yuexiu district, Guangzhou, China in 2008. Of which 1595 (87.8%) were reexamined in 2010 and 1427 (78.5%) were reexamined in 2014. Non-cycloplegic automated refraction and visual acuity test were performed at baseline and the 6-year follow-up examination for all participants. In addition, 50% of the participants were randomly selected for axial length (AL), anterior chamber depth (ACD) and lens thickness (LT) measurements using non-contact partial coherence laser interferometry. Lens power (LP) was calculated with the Bennett’s equation. Results A total of 1300 participants were included in current analysis (2008 mean [SD] age, 51.4 [10.6] years; 54.5% women). Mean change in spherical equivalence (SE) was +0.24 (95% confidence interval [CI], +0.19 to +0.30), +0.51 (95% CI, +0.46 to +0.57), +0.26 (95% CI, +0.15 to +0.38) and -0.05 (95% CI, -0.21 to +0.10) diopters (D) for individuals in the age groups of 35 to 44, 45 to 54, 55 to 64 and 65+ years at baseline, respectively. Corneal power, AL and LT increased while ACD and LP decreased during the follow-up. Baseline SE and changes in biometric factors could explain 97.2% of the variance in longitudinal SE change while LP solely could explain 65.2%. Six-year mean change in cylinder power was -0.16 (95% CI, -0.19 to -0.13) D, the axis of astigmatism changed from “with-the-rule” to “against-the-rule” in 16.4% of the participants and to “oblique” in 0.9%. Conclusions This study confirms a hyperopic shift in the elderly before 65 years old and a myopic shift thereafter. Longitudinal refraction change could be well explained by corresponding biometry changes, especially LP. There is also a shift to “against-the-rule” astigmatism for the adult population. PMID:28854269

[Public spending on health and population health in Algeria: an econometric analysis].

PubMed

Messaili, Moussa; Kaïd Tlilane, Nouara

2017-07-10

Objective: The objective of this study was to estimate the impact of public spending on health, among other determinants of health, on the health of the population in Algeria, using life expectancy (men and women) and infant mortality rates as indicators of health status. Methods: We conducted a longitudinal study over the period from 1974 to 2010 using the ARDL (Autoregressive Distributed Lags) approach to co-integration to estimate the short-term and long-term relationship. Results: Public spending on health has a positive, but not statistically significant impact, in the long and short term, on life expectancy (men and women). However, public spending significantly reduces the infant mortality rate. The long-term impact of the number of hospital beds is significant for the life expectancy of men, but not for women and infant mortality, but is significant for all indicators in the short-term relationship. The most important variables in improving the health of the population are real GDP per capita and fertility rate.

Long-Term Mortality Consequences of Childhood Family Context in Liaoning, China, 1749-1909

PubMed Central

Campbell, Cameron Dougall; Lee, James Z

2009-01-01

We examine the effects on adult and old age mortality of childhood living arrangements and other aspects of family context in early life. We focus on features of family context that have already been shown to be associated with infant or child mortality in historical and developing country populations. We apply discrete-time event-history analysis to longitudinal, individual-level household register data for a rural population in northeast China from the eighteenth and nineteenth centuries. Loss of a mother in childhood, a short preceding birth interval, and high maternal age were all associated with elevated mortality risks later in life. Such effects persist in a model with fixed effects that account for unobserved characteristics of the community and household. An important implication of these results is that in high mortality populations, features of early life family context that are associated with elevated infant and child mortality may also predict adverse mortality outcomes in adulthood. PMID:19278765

Microcracking, microcrack-induced delamination, and longitudinal splitting of advanced composite structures

NASA Technical Reports Server (NTRS)

Nairn, John A.

1992-01-01

A combined analytical and experimental study was conducted to analyze microcracking, microcrack-induced delamination, and longitudinal splitting in polymer matrix composites. Strain energy release rates, calculated by a variational analysis, were used in a failure criterion to predict microcracking. Predictions and test results were compared for static, fatigue, and cyclic thermal loading. The longitudinal splitting analysis accounted for the effects of fiber bridging. Test data are analyzed and compared for longitudinal splitting and delamination under mixed-mode loading. This study emphasizes the importance of using fracture mechanics analyses to understand the complex failure processes that govern composite strength and life.

Bullied children and psychosomatic problems: a meta-analysis.

PubMed

Gini, Gianluca; Pozzoli, Tiziana

2013-10-01

A previous meta-analysis showed that being bullied during childhood is related to psychosomatic problems, but many other studies have been published since then, including some longitudinal studies. We performed a new meta-analysis to quantify the association between peer victimization and psychosomatic complaints in the school-aged population. We searched online databases up to April 2012, and bibliographies of retrieved studies and of narrative reviews, for studies that examined the association between being bullied and psychosomatic complaints in children and adolescents. The original search identified 119 nonduplicated studies, of which 30 satisfied the prestated inclusion criteria. Two separate random effects meta-analyses were performed on 6 longitudinal studies (odds ratio = 2.39, 95% confidence interval, 1.76 to 3.24) and 24 cross-sectional studies (odds ratio = 2.17, 95% confidence interval, 1.91 to 2.46), respectively. Results showed that bullied children and adolescents have a significantly higher risk for psychosomatic problems than non-bullied agemates. In the cross-sectional studies, the magnitude of effect size significantly decreased with the increase of the proportion of female participants in the study sample. No other moderators were statistically significant. The association between being bullied and psychosomatic problems was confirmed. Given that school bullying is a widespread phenomenon in many countries around the world, the present results indicate that bullying should be considered a significant international public health problem.

Developing critical thinking disposition and emotional intelligence of nursing students: a longitudinal research.

PubMed

Kaya, Hülya; Şenyuva, Emine; Bodur, Gönül

2017-01-01

Emotional Intelligence is considered as an important characteristic of nurses that can affect the quality of their work including clinical decision-making, critical thinking, evidence and knowledge use in practice. The study is aimed to determine nursing students' critical thinking disposition and emotional intelligence in an academic year. A longitudinal design. The focus population of this longitudinal study consists of 197 freshman students studying at a faculty of nursing. Asymmetrical cluster sampling method was used to determine sample group and all the students registered in the first year were included in scope of the study. Information Form, California Critical Thinking Disposition Scale and Emotional Intelligence Assessment Scale were used for data collection. SPSS version 11.5 was used for data analysis. Nursing students have a low level of critical thinking disposition and intermediate level of emotional intelligence both at the beginning and end of academic year. There was no statistically significant difference in both skills at the beginning and end of year. There was a statistically significant difference between students' critical thinking disposition and emotional intelligence at the beginning of academic year. There was a positive correlation at a medium level between students' critical thinking disposition and emotional intelligence at the beginning and end of academic year. In light of these results, it is that suggested the study should be prolonged as longitudinal because development of both skills require a long time. The current study holds importance that it sheds light on other relevant studies and nursing education programs. Copyright © 2016 Elsevier Ltd. All rights reserved.

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.

Optimising qualitative longitudinal analysis: Insights from a study of traumatic brain injury recovery and adaptation.

PubMed

Fadyl, Joanna K; Channon, Alexis; Theadom, Alice; McPherson, Kathryn M

2017-04-01

Knowledge about aspects that influence recovery and adaptation in the postacute phase of disabling health events is key to understanding how best to provide appropriate rehabilitation and health services. Qualitative longitudinal research makes it possible to look for patterns, key time points and critical moments that could be vital for interventions and supports. However, strategies that support robust data management and analysis for longitudinal qualitative research in health-care are not well documented in the literature. This article reviews three challenges encountered in a large longitudinal qualitative descriptive study about experiences of recovery and adaptation after traumatic brain injury in New Zealand, and the strategies and technologies used to address them. These were (i) tracking coding and analysis decisions during an extended analysis period; (ii) navigating interpretations over time and in response to new data; and (iii) exploiting data volume and complexity. Concept mapping during coding review, a considered combination of information technologies, employing both cross-sectional and narrative analysis, and an expectation that subanalyses would be required for key topics helped us manage the study in a way that facilitated useful and novel insights. These strategies could be applied in other qualitative longitudinal studies in healthcare inquiry to optimise data analysis and stimulate important insights. © 2016 John Wiley & Sons Ltd.

Longitudinal Analyses of Gut Mucosal Microbiotas in Ulcerative Colitis in Relation to Patient Age and Disease Severity and Duration

PubMed Central

Fite, Alemu; Furrie, Elizabeth; Bahrami, Bahram; Cummings, John H.; Steinke, Douglas T.; Macfarlane, George T.

2013-01-01

Bacteria belonging to the normal colonic microbiota are associated with the etiology of ulcerative colitis (UC). Although several mucosal species have been implicated in the disease process, the organisms and mechanisms involved are unknown. The aim of this investigation was to characterize mucosal biofilm communities over time and to determine the relationship of these bacteria to patient age and disease severity and duration. Multiple rectal biopsy specimens were taken from 33 patients with active UC over a period of 1 year. Real-time PCR was used to quantify mucosal bacteria in UC patients compared to 18 noninflammatory bowel disease controls, and the relationship between indicators of disease severity and bacterial colonization was evaluated by linear regression analysis. Significant differences were detected in bacterial populations on the UC mucosa and in the control group, which varied over the study period. High clinical activity indices (CAI) and sigmoidoscopy scores (SS) were associated with enterobacteria, desulfovibrios, type E Clostridium perfringens, and Enterococcus faecalis, whereas the reverse was true for Clostridium butyricum, Ruminococcus albus, and Eubacterium rectale. Lactobacillus and bifidobacterium numbers were linked with low CAI. Only E. rectale and Clostridium clostridioforme had a high age dependence. These findings demonstrated that longitudinal variations in mucosal bacterial populations occur in UC and that bacterial community structure is related to disease severity. PMID:23269735

Nondestructive nanostraw intracellular sampling for longitudinal cell monitoring

PubMed Central

Cao, Yuhong; Chen, Haodong; Birey, Fikri; Leal-Ortiz, Sergio A.; Han, Crystal M.; Santiago, Juan G.; Paşca, Sergiu P.; Wu, Joseph C.; Melosh, Nicholas A.

2017-01-01

Here, we report a method for time-resolved, longitudinal extraction and quantitative measurement of intracellular proteins and mRNA from a variety of cell types. Cytosolic contents were repeatedly sampled from the same cell or population of cells for more than 5 d through a cell-culture substrate, incorporating hollow 150-nm-diameter nanostraws (NS) within a defined sampling region. Once extracted, the cellular contents were analyzed with conventional methods, including fluorescence, enzymatic assays (ELISA), and quantitative real-time PCR. This process was nondestructive with >95% cell viability after sampling, enabling long-term analysis. It is important to note that the measured quantities from the cell extract were found to constitute a statistically significant representation of the actual contents within the cells. Of 48 mRNA sequences analyzed from a population of cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs), 41 were accurately quantified. The NS platform samples from a select subpopulation of cells within a larger culture, allowing native cell-to-cell contact and communication even during vigorous activity such as cardiomyocyte beating. This platform was applied both to cell lines and to primary cells, including CHO cells, hiPSC-CMs, and human astrocytes derived in 3D cortical spheroids. By tracking the same cell or group of cells over time, this method offers an avenue to understand dynamic cell behavior, including processes such as induced pluripotency and differentiation. PMID:28223521

Longitudinal trends in climate drive flowering time clines in North American Arabidopsis thaliana.

PubMed

Samis, Karen E; Murren, Courtney J; Bossdorf, Oliver; Donohue, Kathleen; Fenster, Charles B; Malmberg, Russell L; Purugganan, Michael D; Stinchcombe, John R

2012-06-01

Introduced species frequently show geographic differentiation, and when differentiation mirrors the ancestral range, it is often taken as evidence of adaptive evolution. The mouse-ear cress (Arabidopsis thaliana) was introduced to North America from Eurasia 150-200 years ago, providing an opportunity to study parallel adaptation in a genetic model organism. Here, we test for clinal variation in flowering time using 199 North American (NA) accessions of A. thaliana, and evaluate the contributions of major flowering time genes FRI, FLC, and PHYC as well as potential ecological mechanisms underlying differentiation. We find evidence for substantial within population genetic variation in quantitative traits and flowering time, and putatively adaptive longitudinal differentiation, despite low levels of variation at FRI, FLC, and PHYC and genome-wide reductions in population structure relative to Eurasian (EA) samples. The observed longitudinal cline in flowering time in North America is parallel to an EA cline, robust to the effects of population structure, and associated with geographic variation in winter precipitation and temperature. We detected major effects of FRI on quantitative traits associated with reproductive fitness, although the haplotype associated with higher fitness remains rare in North America. Collectively, our results suggest the evolution of parallel flowering time clines through novel genetic mechanisms.

The Latent Curve ARMA (P, Q) Panel Model: Longitudinal Data Analysis in Educational Research and Evaluation

ERIC Educational Resources Information Center

Sivo, Stephen; Fan, Xitao

2008-01-01

Autocorrelated residuals in longitudinal data are widely reported as common to longitudinal data. Yet few, if any, researchers modeling growth processes evaluate a priori whether their data have this feature. Sivo, Fan, and Witta (2005) found that not modeling autocorrelated residuals present in longitudinal data severely biases latent curve…

A Comparison of Various MRA Methods Applied to Longitudinal Evaluation Studies in Vocational Education.

ERIC Educational Resources Information Center

Kapes, Jerome T.; And Others

Three models of multiple regression analysis (MRA): single equation, commonality analysis, and path analysis, were applied to longitudinal data from the Pennsylvania Vocational Development Study. Variables influencing weekly income of vocational education students one year after high school graduation were examined: grade point averages (grades…

A State Space Modeling Approach to Mediation Analysis

ERIC Educational Resources Information Center

Gu, Fei; Preacher, Kristopher J.; Ferrer, Emilio

2014-01-01

Mediation is a causal process that evolves over time. Thus, a study of mediation requires data collected throughout the process. However, most applications of mediation analysis use cross-sectional rather than longitudinal data. Another implicit assumption commonly made in longitudinal designs for mediation analysis is that the same mediation…

A 2-D numerical simulation study on longitudinal solute transport and longitudinal dispersion coefficient

NASA Astrophysics Data System (ADS)

Zhang, Wei

2011-07-01

The longitudinal dispersion coefficient, DL, is a fundamental parameter of longitudinal solute transport models: the advection-dispersion (AD) model and various deadzone models. Since DL cannot be measured directly, and since its calibration using tracer test data is quite expensive and not always available, researchers have developed various methods, theoretical or empirical, for estimating DL by easier available cross-sectional hydraulic measurements (i.e., the transverse velocity profile, etc.). However, for known and unknown reasons, DL cannot be satisfactorily predicted using these theoretical/empirical formulae. Either there is very large prediction error for theoretical methods, or there is a lack of generality for the empirical formulae. Here, numerical experiments using Mike21, a software package that implements one of the most rigorous two-dimensional hydrodynamic and solute transport equations, for longitudinal solute transport in hypothetical streams, are presented. An analysis of the evolution of simulated solute clouds indicates that the two fundamental assumptions in Fischer's longitudinal transport analysis may be not reasonable. The transverse solute concentration distribution, and hence the longitudinal transport appears to be controlled by a dimensionless number ?, where Q is the average volumetric flowrate, Dt is a cross-sectional average transverse dispersion coefficient, and W is channel flow width. A simple empirical ? relationship may be established. Analysis and a revision of Fischer's theoretical formula suggest that ɛ influences the efficiency of transverse mixing and hence has restraining effect on longitudinal spreading. The findings presented here would improve and expand our understanding of longitudinal solute transport in open channel flow.

Etiological overlap between obsessive-compulsive disorder and anorexia nervosa: a longitudinal cohort, multigenerational family and twin study

PubMed Central

Cederlöf, Martin; Thornton, Laura M; Baker, Jessica; Lichtenstein, Paul; Larsson, Henrik; Rück, Christian; Bulik, Cynthia M; Mataix-Cols, David

2015-01-01

Obsessive-compulsive disorder (OCD) often co-occurs with anorexia nervosa (AN), a comorbid profile that complicates the clinical management of both conditions. This population-based study aimed to examine patterns of comorbidity, longitudinal risks, shared familial risks and shared genetic factors between OCD and AN at the population level. Participants were individuals with a diagnosis of OCD (N=19,814) or AN (N=8,462) in the Swedish National Patient Register between January 1992 and December 2009; their first-, second- and third-degree relatives; and population-matched (1:10 ratio) unaffected comparison individuals and their relatives. Female twins from the population-based Swedish Twin Register (N=8,550) were also included. Females with OCD had a 16-fold increased risk of having a comorbid diagnosis of AN, whereas males with OCD had a 37-fold increased risk. Longitudinal analyses showed that individuals first diagnosed with OCD had an increased risk for a later diagnosis of AN (risk ratio, RR=3.6), whereas individuals first diagnosed with AN had an even greater risk for a later diagnosis of OCD (RR=9.6). These longitudinal risks were about twice as high for males than for females. First- and second-degree relatives of probands with OCD had an increased risk for AN, and the magnitude of this risk tended to increase with the degree of genetic relatedness. Bivariate twin models revealed a moderate but significant degree of genetic overlap between self-reported OCD and AN diagnoses (ra=0.52, 95% CI: 0.26-0.81), but most of the genetic variance was disorder-specific. The moderately high genetic correlation supports the idea that this frequently observed comorbid pattern is at least in part due to shared genetic factors, though disorder-specific factors are more important. These results have implications for current gene-searching efforts and for clinical practice. PMID:26407789

Population Change, Community Viability, and Migration Intentions in Selected Utah Communities. Research Report 51.

ERIC Educational Resources Information Center

Kim, Yun; And Others

The first phase of a longitudinal research project, "Assessing Rural Communities' Viability and Associated Factors Under Conditions of Population Change," was conducted in 1975 in eight Utah communities (Panguitch, Richfield, Salina, Delta, Moab, Duchesne, Roosevelt, and Vernal) to provide useful information for planners, researchers,…

Health Behaviors of Nursing Students: A Longitudinal Study.

ERIC Educational Resources Information Center

Clement, Madeleine; Jankowski, Louis W.; Bouchard, Louise; Perreault, Michel; Lepage, Yves

2002-01-01

A 3-year study compared 52 undergraduate nursing students with 93 education majors and with the general population. No significant differences among students on 9 health behaviors appeared. Compared with the general population, nursing students had inadequate time for sleep, exercise, and eating breakfast. (Contains 77 references.) (SK)

The Texas saltwater angler population: a longitudinal perspective (1989-2005)

Treesearch

Yung-Ping (Emilio) Tseng; Robert B. Ditton

2007-01-01

This paper focuses on selected human dimensions indicators of the Texas recreational fishery using the Index of Qualitative Variation (IQV) and Spearman Rank-Order Correlation Coefficient. Minority (Hispanic, Spanish, and females) participation and the overall participation rate in saltwater fishing did not keep pace with a dramatic population...

Trajectory of social isolation following hip fracture: an analysis of the English Longitudinal Study of Ageing (ELSA) cohort.

PubMed

Smith, Toby O; Dainty, Jack R; MacGregor, Alex

2018-01-01

social isolation is defined as a lack of meaningful and sustained communication or interactions with social networks. There is limited understanding on the prevalence of social isolation and loneliness in people following hip fracture and no previous understanding of how this changes over time. to determine the prevalence and trajectory of social isolation and loneliness before a hip fracture, during the recovery phase and a minimum of 2 years post-hip fracture in an English population. data were from the English Longitudinal Study of Ageing (ELSA) cohort (2004/5-2014/15). The sample comprised of 215 participants who had sustained a hip fracture. Measures of social isolation and loneliness were analysed through multilevel modelling to determine their trajectories during three-time intervals (pre-fracture; interval at hip fracture and recovery; minimum 2 years post-fracture). The prevalence of social isolation and loneliness were determined pre- and post-fracture. prevalence of social isolation was 19% post-hip fracture and loneliness 13% post-hip fracture. There was no statistically significant change in social isolation pre-fracture compared to a minimum of 2 years post-fracture (P = 0.78). Similarly, there was no statistically significant change in loneliness pre-fracture compared to a minimum of 2 years post-fracture (P = 0.12). this analysis has determined that whilst social isolation and loneliness do not change over time following hip fracture, these remain a significant problem for this population. Interventions are required to address these physical and psychological health needs. This is important as they may have short and longer term health benefits for people post-hip fracture. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.All rights reserved. For permissions, please email: journals.permissions@oup.com

Individual- and community-level correlates of cigarette-smoking trajectories from age 13 to 32 in a U.S. population-based sample.

PubMed

Fuemmeler, Bernard; Lee, Chien-Ti; Ranby, Krista W; Clark, Trenette; McClernon, F Joseph; Yang, Chongming; Kollins, Scott H

2013-09-01

Characterizing smoking behavior is important for informing etiologic models and targeting prevention efforts. This study explored the effects of both individual- and community-level variables in predicting cigarette use vs. non-use and level of use among adolescents as they transition into adulthood. Data on 14,779 youths (53% female) were drawn from the National Longitudinal Study of Adolescent Health (Add Health); a nationally representative longitudinal cohort. A cohort sequential design allowed for examining trajectories of smoking typologies from age 13 to 32 years. Smoking trajectories were evaluated by using a zero-inflated Poisson (ZIP) latent growth analysis and latent class growth analysis modeling approach. Significant relationships emerged between both individual- and community-level variables and smoking outcomes. Maternal and peer smoking predicted increases in smoking over development and were associated with a greater likelihood of belonging to any of the four identified smoking groups versus Non-Users. Conduct problems and depressive symptoms during adolescence were related to cigarette use versus non-use. State-level prevalence of adolescent smoking was related to greater cigarette use during adolescence. Individual- and community-level variables that distinguish smoking patterns within the population aid in understanding cigarette use versus non-use and the quantity of cigarette use into adulthood. Our findings suggest that efforts to prevent cigarette use would benefit from attention to both parental and peer smoking and individual well-being. Future work is needed to better understand the role of variables in the context of multiple levels (individual and community-level) on smoking trajectories. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Discrete associations of the GCKR variant with metabolic risk in a Chinese population: longitudinal change analysis.

PubMed

Xu, Min; Lv, Xiaofei; Xie, Lan; Huang, Xiaolin; Huang, Ya; Chen, Ying; Peng, Kui; Wang, Po; Wang, Weiqing; Qi, Lu; Bi, Yufang; Sun, Yimin; Ning, Guang

2016-02-01

Glucokinase regulatory protein gene (GCKR) variant rs780092 is a novel genetic variant associated with serum triacylglycerol (TG) identified in a genome-wide association study in East Asians. We aimed to investigate associations of rs780092 with incident type 2 diabetes and dyslipidaemia, and the longitudinal changes in glucose and lipid levels. A community-based prospective cohort study was conducted at baseline in 2008, including 5,613 non-diabetic participants (37% male, mean age 57.6 years) with 5 years of follow-up. Blood glucose and lipid was measured at baseline and follow-up. Each rs780092 T-allele was associated with a 17% lower risk of incident type 2 diabetes (HR 0.83 [95% CI 0.73, 0.95]) and 36% higher risk of incident hypertriacylglycerolaemia (OR 1.36 [95% CI 1.08, 1.72]), after adjustment for baseline fasting glucose and TG and other confounders. The T-allele was associated with a 5 year increasing level of log10 TG (β ± SE, 0.01 ± 0.004, p = 0.005). Mediation analysis showed that both baseline TG and the 5 year increase in log10 TG were significant mediators in the associations of rs780092 with risk of diabetes. The risk of incident type 2 diabetes associated with 1 SD increase in total and LDL-cholesterol was 35% and 22% lower in TT carriers compared with CC carriers, respectively (both p for interaction ≤ 0.04). The GCKR rs780092 variant showed opposite-directional associations with type 2 diabetes and hypertriacylglycerolaemia in a Chinese population. Both baseline level and 5 year change in serum TG were mediators of the association between the genetic variant and type 2 diabetes.

Associations between sensory loss and social networks, participation, support, and loneliness: Analysis of the Canadian Longitudinal Study on Aging.

PubMed

Mick, Paul; Parfyonov, Maksim; Wittich, Walter; Phillips, Natalie; Kathleen Pichora-Fuller, M

2018-01-01

To determine if hearing loss, vision loss, and dual sensory loss were associated with social network diversity, social participation, availability of social support, and loneliness, respectively, in a population-based sample of older Canadians and to determine whether age or sex modified the associations. Cross-sectional population-based study. Canada. The sample included 21 241 participants in the Canadian Longitudinal Study on Aging tracking cohort. The sample was nationally representative of English- and French-speaking, non-institutionalized 45- to 89-year-old Canadians who did not live on First Nations reserves and who had normal cognition. Participants with missing data for any of the variables in the multivariable regression models were excluded from analysis. Hearing and vision loss were determined by self-report. Dual sensory loss was defined as reporting both hearing and vision loss. Univariate analyses were performed to assess cross-sectional associations between hearing, vision, and dual sensory loss, and social, demographic, and medical variables. Multivariable regression models were used to analyze cross-sectional associations between each type of sensory loss and social network diversity, social participation, availability of social support, and loneliness. Vision loss (in men) and dual sensory loss (in 65- to 85-year-olds) were independently associated with reduced social network diversity. Vision loss and dual sensory loss (in 65- to 85-year-olds) were each independently associated with reduced social participation. All forms of sensory loss were associated with both low availability of social support and loneliness. Sensory impairment is associated with reduced social function in older Canadians. Interventions and research that address the social needs of older individuals with sensory loss are needed. Copyright© the College of Family Physicians of Canada.

Monthly food insecurity assessment in rural mkushi district, Zambia: a longitudinal analysis.

PubMed

Na, Muzi; Caswell, Bess L; Talegawkar, Sameera A; Palmer, Amanda

2017-03-16

Perception-based scales are widely used for household food insecurity (HFI) assessment but were only recently added in national surveys. The frequency of assessments needed to characterize dynamics in HFI over time is largely unknown. The study aims to examine longitudinal changes in monthly reported HFI at both population- and household-level. A total of 157 households in rural Mkushi District whose children were enrolled in the non-intervened arm of an efficacy trial of biofortified maize were included in the analysis. HFI was assessed by a validated 8-item perception-based Likert scale on a monthly basis from October 2012 to March 2013 (6 visits), characterizing mostly the lean season. An HFI index was created by summing scores over the Likert scale, with a possible range of 0-32. The Wilcoxon matched signed-ranks test was used to compare distribution of HFI index between visits. A random effect model was fit to quantify the sources of variance in indices at household level. The median [IQR] HFI index was 4.5 [2, 8], 5 [1, 8], 4 [1, 7], 4 [1, 6], 3 [1, 7] and 4 [1, 6] at the six monthly visits, respectively. HFI index was significantly higher in visit 1 and 2 than visit 3-6 and on average the index decreased by 0.25 points per visit. Within- and between-household variance in the index were 10.6 and 8.8, respectively. The small change in mean monthly HFI index over a single lean season indicated that a seasonal HFI measure may be sufficient for monitoring purposes at population level. Yet, higher variation within households suggests that repeated assessments may be required to avoid risk of misclassification at household level and to target households with the greatest risk of food insecurity.

Identification of five chronic obstructive pulmonary disease subgroups with different prognoses in the ECLIPSE cohort using cluster analysis.

PubMed

Rennard, Stephen I; Locantore, Nicholas; Delafont, Bruno; Tal-Singer, Ruth; Silverman, Edwin K; Vestbo, Jørgen; Miller, Bruce E; Bakke, Per; Celli, Bartolomé; Calverley, Peter M A; Coxson, Harvey; Crim, Courtney; Edwards, Lisa D; Lomas, David A; MacNee, William; Wouters, Emiel F M; Yates, Julie C; Coca, Ignacio; Agustí, Alvar

2015-03-01

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease that likely includes clinically relevant subgroups. To identify subgroups of COPD in ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) subjects using cluster analysis and to assess clinically meaningful outcomes of the clusters during 3 years of longitudinal follow-up. Factor analysis was used to reduce 41 variables determined at recruitment in 2,164 patients with COPD to 13 main factors, and the variables with the highest loading were used for cluster analysis. Clusters were evaluated for their relationship with clinically meaningful outcomes during 3 years of follow-up. The relationships among clinical parameters were evaluated within clusters. Five subgroups were distinguished using cross-sectional clinical features. These groups differed regarding outcomes. Cluster A included patients with milder disease and had fewer deaths and hospitalizations. Cluster B had less systemic inflammation at baseline but had notable changes in health status and emphysema extent. Cluster C had many comorbidities, evidence of systemic inflammation, and the highest mortality. Cluster D had low FEV1, severe emphysema, and the highest exacerbation and COPD hospitalization rate. Cluster E was intermediate for most variables and may represent a mixed group that includes further clusters. The relationships among clinical variables within clusters differed from that in the entire COPD population. Cluster analysis using baseline data in ECLIPSE identified five COPD subgroups that differ in outcomes and inflammatory biomarkers and show different relationships between clinical parameters, suggesting the clusters represent clinically and biologically different subtypes of COPD.

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

Sexual orientation and suicidal behaviour in adolescents and young adults: systematic review and meta-analysis.

PubMed

Miranda-Mendizábal, A; Castellví, P; Parés-Badell, O; Almenara, J; Alonso, I; Blasco, M J; Cebrià, A; Gabilondo, A; Gili, M; Lagares, C; Piqueras, J A; Roca, M; Rodríguez-Marín, J; Rodríguez-Jiménez, T; Soto-Sanz, V; Vilagut, G; Alonso, J

2017-08-01

Background Research suggests that lesbian, gay and bisexual (LGB) adolescents have a higher risk of suicidal behaviours than their heterosexual peers, but little is known about specific risk factors. Aims To assess sexual orientation as a risk factor for suicidal behaviours, and to identify other risk factors among LGB adolescents and young adults. Method A systematic search was made of six databases up to June 2015, including a grey literature search. Population-based longitudinal studies considering non-clinical populations aged 12-26 years and assessing being LGB as a risk factor for suicidal behaviour compared with being heterosexual, or evaluating risk factors for suicidal behaviour within LGB populations, were included. Random effect models were used in meta-analysis. Results Sexual orientation was significantly associated with suicide attempts in adolescents and youths (OR = 2.26, 95% CI 1.60-3.20). Gay or bisexual men were more likely to report suicide attempts compared with heterosexual men (OR = 2.21, 95% CI 1.21-4.04). Based on two studies, a non-significant positive association was found between depression and suicide attempts in LGB groups. Conclusions Sexual orientation is associated with a higher risk of suicide attempt in young people. Further research is needed to assess completed suicide, and specific risk factors affecting the LGB population. © The Royal College of Psychiatrists 2017.

Gambling Harm and Crime Careers.

PubMed

May-Chahal, Corinne; Humphreys, Leslie; Clifton, Alison; Francis, Brian; Reith, Gerda

2017-03-01

Incarcerated populations across the world have been found to be consistently and significantly more vulnerable to problem gambling than general populations in the same countries. In an effort to gain a more specific understanding of this vulnerability the present study applied latent class analysis and criminal career theory to gambling data collected from a sample of English and Scottish, male and female prisoners (N = 1057). Theoretical links between gambling and crime were tested through three hypotheses: (1) that prisoners in the UK would have higher rates of problem gambling behaviour than the national population; (2) that if the link between gambling and crime is coincidental, gambling behaviour would be highly prevalent in an offending population, and (3) if connections between gambling behaviour and offending are co-symptomatic a mediating factor would show a strong association. The first of these was supported, the second was not supported and the third was partially supported. Latent class analysis found six gambling behaviour clusters measured by responses to the Problem Gambling Severity Index, primarily distinguished by loss chasing behaviour. Longitudinal offending data drawn from the Police National Computer database found four criminal career types, distinguished by frequency and persistence over time. A significant association was found between higher level loss chasing and high rate offending in criminal careers suggesting that impulse control may be a mediating factor for both gambling harm and criminal careers.

Association of Serum Thyrotropin with Anthropometric Markers of Obesity in the General Population.

PubMed

Tiller, Daniel; Ittermann, Till; Greiser, Karin H; Meisinger, Christa; Agger, Carsten; Hofman, Albert; Thuesen, Betina; Linneberg, Allan; Peeters, Robin; Franco, Oscar; Heier, Margit; Kluttig, Alexander; Werdan, Karl; Stricker, Bruno; Schipf, Sabine; Markus, Marcello; Dörr, Marcus; Völzke, Henry; Haerting, Johannes

2016-09-01

Except from associations study with body weight, there are few longitudinal data regarding the association between thyroid function and anthropometric measurements such as waist circumference, waist-to-hip ratio, or waist-to height ratio. This study aimed to investigate the association of thyrotropin (TSH) at baseline with changes in different anthropometric markers between baseline and follow-up in the general population. Data were used from four population-based longitudinal cohort studies and one population-based cross-sectional study. A total of 16,902 (8204 males) subjects aged 20-95 years from the general population were studied. Body mass index, waist circumference, waist-to-hip ratio, and waist-to-height ratio were measured. Multivariable median regression models were calculated adjusting for the following covariates: age, sex, baseline value of the respective anthropometric marker, smoking status, follow-up-time period, and study site. In cross-sectional analyses, serum TSH within the reference range was positively associated with waist circumference (β = 0.94 cm [confidence interval (CI) 0.56-1.32]) and waist-to-height-ratio (β = 0.029 [CI 0.017-0.042]). These associations were also present for the full range of TSH. In the longitudinal analyses, serum TSH at baseline was inversely associated with a five-year change of all considered anthropometric measures within the prior defined study-specific reference range, as well as in the full range of serum TSH. High TSH serum levels were positively associated with current anthropometric markers, even in the study-specific reference ranges. In contrast, high TSH serum levels were associated with decreased anthropometric markers over a time span of approximately five years. Further research is needed to determine possible clinical implications as well as public health consequences of these findings.

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.

Multivariate analysis of longitudinal rates of change.

PubMed

Bryan, Matthew; Heagerty, Patrick J

2016-12-10

Longitudinal data allow direct comparison of the change in patient outcomes associated with treatment or exposure. Frequently, several longitudinal measures are collected that either reflect a common underlying health status, or characterize processes that are influenced in a similar way by covariates such as exposure or demographic characteristics. Statistical methods that can combine multivariate response variables into common measures of covariate effects have been proposed in the literature. Current methods for characterizing the relationship between covariates and the rate of change in multivariate outcomes are limited to select models. For example, 'accelerated time' methods have been developed which assume that covariates rescale time in longitudinal models for disease progression. In this manuscript, we detail an alternative multivariate model formulation that directly structures longitudinal rates of change and that permits a common covariate effect across multiple outcomes. We detail maximum likelihood estimation for a multivariate longitudinal mixed model. We show via asymptotic calculations the potential gain in power that may be achieved with a common analysis of multiple outcomes. We apply the proposed methods to the analysis of a trivariate outcome for infant growth and compare rates of change for HIV infected and uninfected infants. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Prevalence of Hyperactivity-Impulsivity and Inattention Among Canadian Children: Findings from the First Data Collection Cycle (1994-1995) of the National Longitudinal Survey of Children and Youth. Final Report

ERIC Educational Resources Information Center

Romano, Elisa; Baillargeon, Raymond H.; Tremblay, Richard E.

2002-01-01

Hyperactivity, impulsivity, and inattention are among the most common behaviour problems in children. The aim of this study was to estimate the prevalence of hyperactivity-impulsivity and inattention in the Canadian population of 2-11-year-old girls and boys, using data from the first National Longitudinal Survey of Children and Youth (NLSCY)…

Longitudinal Study of a Novel, Performance-based Measure of Everyday Functional Competence

DTIC Science & Technology

2014-04-01

longitudinal characteristics of the UPSA. Over the past year we have enrolled 25 subjects into our protocol. Of these 24 received the six week follow up... characteristics of the UPSA in these populations, including the severity of decline in this measure over time, the relationship of decline to cognitive...changes in order to determine the validity of the UPSA, and its technical psychometric characteristics (e.g., test-retest reliability). We will

Does gender inequity increase men's mortality risk in the United States? A multilevel analysis of data from the National Longitudinal Mortality Study.

PubMed

Kavanagh, Shane A; Shelley, Julia M; Stevenson, Christopher

2017-12-01

A number of theoretical approaches suggest that gender inequity may give rise to health risks for men. This study undertook a multilevel analysis to ascertain if state-level measures of gender inequity are predictors of men's mortality in the United States. Data for the analysis were taken primarily from the National Longitudinal Mortality Study, which is based on a random sample of the non-institutionalised population. The full data set included 174,703 individuals nested within 50 states and had a six-year follow-up for mortality. Gender inequity was measured by nine variables: higher education, reproductive rights, abortion provider access, elected office, management, business ownership, labour force participation, earnings and relative poverty. Covariates at the individual level were age, income, education, race/ethnicity, marital status and employment status. Covariates at the state level were income inequality and per capita gross domestic product. The results of logistic multilevel modelling showed a number of measures of state-level gender inequity were significantly associated with men's mortality. In all of these cases greater gender inequity was associated with an increased mortality risk. In fully adjusted models for all-age adult men the elected office (OR 1.05 95% CI 1.01-1.09), business ownership (OR 1.04 95% CI 1.01-1.08), earnings (OR 1.04 95% CI 1.01-1.08) and relative poverty (OR 1.07 95% CI 1.03-1.10) measures all showed statistically significant effects for each 1 standard deviation increase in the gender inequity z -score. Similar effects were seen for working-age men. In older men (65+ years) only the earnings and relative poverty measures were statistically significant. This study provides evidence that gender inequity may increase men's health risks. The effect sizes while small are large enough across the range of gender inequity identified to have important population health implications.

Association between earthquake events and cholera outbreaks: a cross-country 15-year longitudinal analysis.

PubMed

Sumner, Steven A; Turner, Elizabeth L; Thielman, Nathan M

2013-12-01

Large earthquakes can cause population displacement, critical sanitation infrastructure damage, and increased threats to water resources, potentially predisposing populations to waterborne disease epidemics such as cholera. Problem The risk of cholera outbreaks after earthquake disasters remains uncertain. A cross-country analysis of World Health Organization (WHO) cholera data that would contribute to this discussion has yet to be published. A cross-country longitudinal analysis was conducted among 63 low- and middle-income countries from 1995-2009. The association between earthquake disasters of various effect sizes and a relative spike in cholera rates for a given country was assessed utilizing fixed-effects logistic regression and adjusting for gross domestic product per capita, water and sanitation level, flooding events, percent urbanization, and under-five child mortality. Also, the association between large earthquakes and cholera rate increases of various degrees was assessed. Forty-eight of the 63 countries had at least one year with reported cholera infections during the 15-year study period. Thirty-six of these 48 countries had at least one earthquake disaster. In adjusted analyses, country-years with ≥10,000 persons affected by an earthquake had 2.26 times increased odds (95 CI, 0.89-5.72, P = .08) of having a greater than average cholera rate that year compared to country-years having <10,000 individuals affected by an earthquake. The association between large earthquake disasters and cholera infections appeared to weaken as higher levels of cholera rate increases were tested. A trend of increased risk of greater than average cholera rates when more people were affected by an earthquake in a country-year was noted. However these findings did not reach statistical significance at traditional levels and may be due to chance. Frequent large-scale cholera outbreaks after earthquake disasters appeared to be relatively uncommon.

A Relationship Between Early Language Skills and Adult Autistic-Like Traits: Evidence from a Longitudinal Population-Based Study.

PubMed

Armstrong, Rebecca; Whitehouse, Andrew J O; Scott, James G; Copland, David A; McMahon, Katie L; Fleming, Sophie; Arnott, Wendy

2017-05-01

The current study examined the relationship between early language ability and autistic-like traits in adulthood, utilising data from 644 participants from a longitudinal study of the general population. Language performance at 2 years was measured with the Language Development Survey (LDS), and at 20 years the participants completed the Autism-Spectrum Quotient (AQ). Vocabulary size at 2 years was negatively associated with Total AQ score, as well as scores on the Communication, and Social Skills subscales. Adults who had been late talkers were also more likely to have 'high' scores on the Communication subscale. This is the first study to show an association between early language ability and autistic-like traits in adulthood.

Self-Concept and Academic Achievement: A Meta-Analysis of Longitudinal Relations

ERIC Educational Resources Information Center

Huang, Chiungjung

2011-01-01

The relation between self-concept and academic achievement was examined in 39 independent and longitudinal samples through the integration of meta-analysis and path analysis procedures. For relations with more than 3 independent samples, the mean observed correlations ranged from 0.20 to 0.27 between prior self-concept and subsequent academic…

Utilization of nuclear medicine scintigraphy in Taiwan, 1997-2009.

PubMed

Hung, Mao-Chin; Hsieh, Wanhua Annie; Chang, Peter Wushou; Hwang, Jeng-Jong

2011-12-01

To analyze the utilization of nuclear medicine scintigraphy in the Taiwanese population within the national health-care system between 1997 and 2009. Based on the Taiwan's National Health Insurance Research Database of 1997-2009, a retrospective population-based analysis was conducted. Descriptive statistics and regression analysis were employed to analyze the frequencies and longitudinal trends in the utilization of diagnostic nuclear medicine procedures during the period. In addition, correlation analysis was applied to determine the correlated factors in the utility of nuclear medicine scintigraphy. The annual total nuclear medicine scintigraphy was estimated to be 256,389 on average in 1997-2009 and 11.7 per 1,000 population over the period. The frequency had increased by 67% over the years, from 8.2 per 1,000 population in 1997 to 13.7 per 1,000 population in 2009. The most frequently performed procedures were whole-body bone scans (33.4% of total) and myocardial perfusion scans (29.4% of total), with 4,615 and 5,620 increments per year, respectively. Most patients were in the age group of 41-65 years old when taking examinations. In addition, male subjects were slightly more than female patients (51.5 vs. 48.5%). Furthermore, the frequencies of whole-body bone scans and PET scans were proportional to the incidences of cancers (correlation coefficients were 0.96 and 0.94, respectively). The utilization of nuclear medicine scintigraphy with the National Health Insurance system in Taiwan has been changed considerably in the past 13 years. Both whole-body bone scan and myocardial perfusion scan were performed most often with significantly increases. The trend of nuclear medicine scintigraphy may have potential impact on making health-care policy in Taiwan.

Quantitative Amyloid Imaging in Autosomal Dominant Alzheimer's Disease: Results from the DIAN Study Group.

PubMed

Su, Yi; Blazey, Tyler M; Owen, Christopher J; Christensen, Jon J; Friedrichsen, Karl; Joseph-Mathurin, Nelly; Wang, Qing; Hornbeck, Russ C; Ances, Beau M; Snyder, Abraham Z; Cash, Lisa A; Koeppe, Robert A; Klunk, William E; Galasko, Douglas; Brickman, Adam M; McDade, Eric; Ringman, John M; Thompson, Paul M; Saykin, Andrew J; Ghetti, Bernardino; Sperling, Reisa A; Johnson, Keith A; Salloway, Stephen P; Schofield, Peter R; Masters, Colin L; Villemagne, Victor L; Fox, Nick C; Förster, Stefan; Chen, Kewei; Reiman, Eric M; Xiong, Chengjie; Marcus, Daniel S; Weiner, Michael W; Morris, John C; Bateman, Randall J; Benzinger, Tammie L S

2016-01-01

Amyloid imaging plays an important role in the research and diagnosis of dementing disorders. Substantial variation in quantitative methods to measure brain amyloid burden exists in the field. The aim of this work is to investigate the impact of methodological variations to the quantification of amyloid burden using data from the Dominantly Inherited Alzheimer's Network (DIAN), an autosomal dominant Alzheimer's disease population. Cross-sectional and longitudinal [11C]-Pittsburgh Compound B (PiB) PET imaging data from the DIAN study were analyzed. Four candidate reference regions were investigated for estimation of brain amyloid burden. A regional spread function based technique was also investigated for the correction of partial volume effects. Cerebellar cortex, brain-stem, and white matter regions all had stable tracer retention during the course of disease. Partial volume correction consistently improves sensitivity to group differences and longitudinal changes over time. White matter referencing improved statistical power in the detecting longitudinal changes in relative tracer retention; however, the reason for this improvement is unclear and requires further investigation. Full dynamic acquisition and kinetic modeling improved statistical power although it may add cost and time. Several technical variations to amyloid burden quantification were examined in this study. Partial volume correction emerged as the strategy that most consistently improved statistical power for the detection of both longitudinal changes and across-group differences. For the autosomal dominant Alzheimer's disease population with PiB imaging, utilizing brainstem as a reference region with partial volume correction may be optimal for current interventional trials. Further investigation of technical issues in quantitative amyloid imaging in different study populations using different amyloid imaging tracers is warranted.

Quantitative Amyloid Imaging in Autosomal Dominant Alzheimer’s Disease: Results from the DIAN Study Group

PubMed Central

Su, Yi; Blazey, Tyler M.; Owen, Christopher J.; Christensen, Jon J.; Friedrichsen, Karl; Joseph-Mathurin, Nelly; Wang, Qing; Hornbeck, Russ C.; Ances, Beau M.; Snyder, Abraham Z.; Cash, Lisa A.; Koeppe, Robert A.; Klunk, William E.; Galasko, Douglas; Brickman, Adam M.; McDade, Eric; Ringman, John M.; Thompson, Paul M.; Saykin, Andrew J.; Ghetti, Bernardino; Sperling, Reisa A.; Johnson, Keith A.; Salloway, Stephen P.; Schofield, Peter R.; Masters, Colin L.; Villemagne, Victor L.; Fox, Nick C.; Förster, Stefan; Chen, Kewei; Reiman, Eric M.; Xiong, Chengjie; Marcus, Daniel S.; Weiner, Michael W.; Morris, John C.; Bateman, Randall J.; Benzinger, Tammie L. S.

2016-01-01

Amyloid imaging plays an important role in the research and diagnosis of dementing disorders. Substantial variation in quantitative methods to measure brain amyloid burden exists in the field. The aim of this work is to investigate the impact of methodological variations to the quantification of amyloid burden using data from the Dominantly Inherited Alzheimer’s Network (DIAN), an autosomal dominant Alzheimer’s disease population. Cross-sectional and longitudinal [11C]-Pittsburgh Compound B (PiB) PET imaging data from the DIAN study were analyzed. Four candidate reference regions were investigated for estimation of brain amyloid burden. A regional spread function based technique was also investigated for the correction of partial volume effects. Cerebellar cortex, brain-stem, and white matter regions all had stable tracer retention during the course of disease. Partial volume correction consistently improves sensitivity to group differences and longitudinal changes over time. White matter referencing improved statistical power in the detecting longitudinal changes in relative tracer retention; however, the reason for this improvement is unclear and requires further investigation. Full dynamic acquisition and kinetic modeling improved statistical power although it may add cost and time. Several technical variations to amyloid burden quantification were examined in this study. Partial volume correction emerged as the strategy that most consistently improved statistical power for the detection of both longitudinal changes and across-group differences. For the autosomal dominant Alzheimer’s disease population with PiB imaging, utilizing brainstem as a reference region with partial volume correction may be optimal for current interventional trials. Further investigation of technical issues in quantitative amyloid imaging in different study populations using different amyloid imaging tracers is warranted. PMID:27010959

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.

Comparison of endothelial changes and power settings between torsional and longitudinal phacoemulsification.

PubMed

Reuschel, Anna; Bogatsch, Holger; Barth, Thomas; Wiedemann, Renate

2010-11-01

To compare the intraoperative and postoperative outcomes of conventional longitudinal phacoemulsification and torsional phacoemulsification. Department of Ophthalmology, University of Leipzig, Germany. Randomized single-center clinical trial. Eyes with senile cataract were randomized to have phacoemulsification using the Infiniti Vision System and the torsional mode (OZil) or conventional longitudinal mode. Primary outcomes were corrected distance visual acuity (CDVA) and central endothelial cell density (ECD), calculated according to the Conference on Harmonisation-E9 Guidelines in which missing values were substituted by the median in each group (primary analysis) and the loss was then calculated using actual data (secondary analysis). Secondary outcomes were ultrasound (US) time, cumulative dissipated energy (CDE), and percentage total equivalent power in position 3. Postoperative follow-up was at 3 months. The mean preoperative CDVA was 0.41 logMAR in the torsional group and 0.38 logMAR in the longitudinal group, improving to 0.07 logMAR postoperatively in both groups. The mean ECD loss was 7.2% ± 4.6% in the torsional group (72 patients) and 7.1% ± 4.4% in the longitudinal group (76 patients), with no statistically significant differences in the primary analysis (P = .342) or secondary analysis (P = .906). The mean US time, CDE, and percentage total equivalent power in position 3 were statistically significantly lower in the torsional group (98 patients) than in the longitudinal group (94 patients) (P<.001). The torsional mode was as safe as the longitudinal mode in phacoemulsification for age-related cataract. Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Child incarceration and long-term adult health outcomes: a longitudinal study.

PubMed

Barnert, Elizabeth S; Abrams, Laura S; Tesema, Lello; Dudovitz, Rebecca; Nelson, Bergen B; Coker, Tumaini; Bath, Eraka; Biely, Christopher; Li, Ning; Chung, Paul J

2018-03-12

Purpose Although incarceration may have life-long negative health effects, little is known about associations between child incarceration and subsequent adult health outcomes. The paper aims to discuss this issue. Design/methodology/approach The authors analyzed data from 14,689 adult participants in the National Longitudinal Study of Adolescent to Adult Health (Add Health) to compare adult health outcomes among those first incarcerated between 7 and 13 years of age (child incarceration); first incarcerated at>or=14 years of age; and never incarcerated. Findings Compared to the other two groups, those with a history of child incarceration were disproportionately black or Hispanic, male, and from lower socio-economic strata. Additionally, individuals incarcerated as children had worse adult health outcomes, including general health, functional limitations (climbing stairs), depressive symptoms, and suicidality, than those first incarcerated at older ages or never incarcerated. Research limitations/implications Despite the limitations of the secondary database analysis, these findings suggest that incarcerated children are an especially medically vulnerable population. Practical implications Programs and policies that address these medically vulnerable children's health needs through comprehensive health and social services in place of, during, and/or after incarceration are needed. Social implications Meeting these unmet health and social service needs offers an important opportunity to achieve necessary health care and justice reform for children. Originality/value No prior studies have examined the longitudinal relationship between child incarceration and adult health outcomes.

Maternal depressive symptoms across early childhood and asthma in school children: findings from a Longitudinal Australian Population Based Study.

PubMed

Giallo, Rebecca; Bahreinian, Salma; Brown, Stephanie; Cooklin, Amanda; Kingston, Dawn; Kozyrskyj, Anita

2015-01-01

There is a growing body of evidence attesting to links between early life exposure to stress and childhood asthma. However, available evidence is largely based on small, genetically high risk samples. The aim of this study was to explore the associations between the course of maternal depressive symptoms across early childhood and childhood asthma in a nationally representative longitudinal cohort study of Australian children. Participants were 4164 children and their biological mothers from the Longitudinal Study of Australian Children. Latent class analysis identified three trajectories of maternal depressive symptoms across four biennial waves from the first postnatal year to when children were 6-7 years: minimal symptoms (74.6%), sub-clinical symptoms (20.8%), and persistent and increasing high symptoms (4.6%). Logistic regression analyses revealed that childhood asthma at age 6-7 years was associated with persistent and increasing high depressive symptoms after accounting for known risk factors including smoking during pregnancy and maternal history of asthma (adjusted OR 2.36, 95% CI 1.61-3.45), p.001). Our findings from a nationally representative sample of Australian children provide empirical support for a relationship between maternal depressive symptoms across the early childhood period and childhood asthma. The burden of disease from childhood asthma may be reduced by strengthening efforts to promote maternal mental health in the early years of parenting.

Brief Intervention for Truant Youth Sexual Risk Behavior and Alcohol Use: A Parallel Process Growth Model Analysis

PubMed Central

Dembo, Richard; Briones-Robinson, Rhissa; Ungaro, Rocio; Barrett, Kimberly; Gulledge, Laura; Winters, Ken C.; Belenko, Steven; Karas, Lora M.; Wareham, Jennifer

2011-01-01

Truant youths represent a challenging, yet very promising group of at-risk youth to study. In addition to problems in school, they frequently experience troubled family situations, emotional/ psychological problems, involvement in substance use, and delinquency. Given the problems often experienced by truant youth, it is likely they are engaging in alcohol use and sexual risk behavior at a higher rate, than the general youth population. Identification of these youths’ problems and early placement into effective intervention services would benefit them, their families, and society. The current study presents interim findings from an ongoing, NIDA-funded experimental, Brief Intervention (BI) study involving truant youths and their parent/guardians. Baseline, 3-month, 6-month, and 12-month follow up data were analyzed to determine whether alcohol use and sexual risk behaviors were longitudinally related, examine the effects of the intervention on longitudinal alcohol use and sexual risk behaviors, identify latent subgroups of youths in the data for alcohol use and sexual risk behaviors, and determine whether the intervention influenced these subgroups. Results indicated alcohol use and sexual risk were longitudinally related. Subgroups of youth were also identified based on alcohol use and sexual risk behavior levels and trends. Further, limited treatment effects were observed for alcohol use. Implications of the results for future research and service delivery are considered. PMID:25242878

The prevalence and correlates of self-harm ideation trajectories in Australian women from pregnancy to 4-years postpartum.

PubMed

Giallo, Rebecca; Pilkington, Pamela; Borschmann, Rohan; Seymour, Monique; Dunning, Melissa; Brown, Stephanie

2018-03-15

Women in the perinatal period are at increased risk of experiencing self-harm ideation. The current study longitudinally examines the prevalence, trajectories, and correlates of self-harm ideation in a population-based sample of Australian women from pregnancy through to the early years of parenting. Drawing on data from 1507 women participating in a prospective pregnancy cohort study, data were collected during pregnancy, at 3-, 6-, 12-, and 18-months postpartum, and 4-years postpartum. Longitudinal Latent Class Analysis was conducted to identify groups of women based on their responses to thoughts of self-harm at each time-point. Logistic regression analysis was used to identify factors associated with group membership. Approximately 4-5% of women reported experiencing self-harm ideation at each time-point from pregnancy to 4-years postpartum. Cross-sectional analyses revealed that self-harm ideation was most frequently endorsed in the first 12-months postpartum (4.6%), and approximately 15% of women reported self-harm ideation at least once during the study period. Longitudinally, approximately 7% of women had an enduring pattern of self-harm ideation from pregnancy to 4-years postpartum. Women who had experienced a range of preconception and current social health issues and disadvantage were at increased risk of self-harm ideation over time. Limitations included use of brief measures, along with an underrepresentation of participants with particular socio-demographic characteristics. A proportion of women are at increased risk of experiencing self-harm ideation during the perinatal period and in the early years of parenting, underscoring the need for early identification during pregnancy and early postpartum to facilitate timely early intervention. Copyright © 2018 Elsevier B.V. All rights reserved.

Bioecological Theory, Early Child Development and the Validation of the Population-Level Early Development Instrument

ERIC Educational Resources Information Center

Guhn, Martin; Goelman, Hillel

2011-01-01

The Early Development Instrument (EDI; Janus and Offord in "Canadian Journal of Behavioural Science" 39:1-22, 2007) project is a Canadian population-level, longitudinal research project, in which teacher ratings of Kindergarten children's early development and wellbeing are linked to health and academic achievement variables at the…

Prevalence of Tourette Syndrome and Chronic Tics in the Population-Based Avon Longitudinal Study of Parents and Children Cohort

ERIC Educational Resources Information Center

Scharf, Jeremiah M.; Miller, Laura L.; Mathews, Carol A.; Ben-Shlomo, Yoav

2012-01-01

Objective: Recent epidemiologic studies have demonstrated that Tourette syndrome (TS) and chronic tic disorder (CT) are more common than previously recognized. However, few population-based studies have examined the prevalence of co-occurring neuropsychiatric conditions such as obsessive-compulsive disorder (OCD) and…

Application of a dynamic population-based model for evaluation of exposure reduction strategies in the baking industry

NASA Astrophysics Data System (ADS)

Meijster, Tim; Warren, Nick; Heederik, Dick; Tielemans, Erik

2009-02-01

Recently a dynamic population model was developed that simulates a population of bakery workers longitudinally through time and tracks the development of work-related sensitisation and respiratory symptoms in each worker. Input for this model comes from cross-sectional and longitudinal epidemiological studies which allowed estimation of exposure response relationships and disease transition probabilities This model allows us to study the development of diseases and transitions between disease states over time in relation to determinants of disease including flour dust and/or allergen exposure. Furthermore it enables more realistic modelling of the health impact of different intervention strategies at the workplace (e.g. changes in exposure may take several years to impact on ill-health and often occur as a gradual trend). A large dataset of individual full-shift exposure measurements and real-time exposure measurements were used to obtain detailed insight into the effectiveness of control measures and other determinants of exposure. Given this information a population wide reduction of the median exposure with 50% was evaluated in this paper.

The persistent prevalence and evolution of cross-family recombinant coronavirus GCCDC1 among a bat population: a two-year follow-up.

PubMed

Obameso, Joseph O; Li, Hong; Jia, Hao; Han, Min; Zhu, Shiyan; Huang, Canping; Zhao, Yuhui; Zhao, Min; Bai, Yu; Yuan, Fei; Zhao, Honglan; Peng, Xia; Xu, Wen; Tan, Wenjie; Zhao, Yingze; Yuen, Kwok-Yung; Liu, William J; Lu, Lin; Gao, George F

2017-12-01

Bats are connected with the increasing numbers of emerging and re-emerging viruses that may break the species barrier and spread into the human population. Coronaviruses are one of the most common viruses discovered in bats, which were considered as the natural source of recent human-susceptible coronaviruses, i.e. SARS-COV and MERS-CoV. Our previous study reported the discovery of a bat-derived putative cross-family recombinant coronavirus with a reovirus gene p10, named as Ro-BatCoV GCCDC1. In this report, through a two-year follow-up of a special bat population in one specific cave of south China, we illustrate that Ro-BatCoV GCCDC1 persistently circulates among bats. Notably, through the longitudinal observation, we identified the dynamic evolution of Ro-BatCoV GCCDC1 in bats represented by continuously recombination events. Our study provides the first glimpse of the virus evolution in one longitudinally observed bat population cohort and underlines the surveillance and pre-warning of potential interspecies transmittable viruses in bats.

Reliability of an fMRI Paradigm for Emotional Processing in a Multisite Longitudinal Study

PubMed Central

Gee, Dylan G.; McEwen, Sarah C.; Forsyth, Jennifer K.; Haut, Kristen M.; Bearden, Carrie E.; Addington, Jean; Goodyear, Bradley; Cadenhead, Kristin S.; Mirzakhanian, Heline; Cornblatt, Barbara A.; Olvet, Doreen; Mathalon, Daniel H.; McGlashan, Thomas H.; Perkins, Diana O.; Belger, Aysenil; Seidman, Larry J.; Thermenos, Heidi; Tsuang, Ming T.; van Erp, Theo G.M.; Walker, Elaine F.; Hamann, Stephan; Woods, Scott W.; Constable, Todd; Cannon, Tyrone D.

2015-01-01

Multisite neuroimaging studies can facilitate the investigation of brain-related changes in many contexts, including patient groups that are relatively rare in the general population. Though multisite studies have characterized the reliability of brain activation during working memory and motor functional magnetic resonance imaging tasks, emotion processing tasks, pertinent to many clinical populations, remain less explored. A traveling participants study was conducted with eight healthy volunteers scanned twice on consecutive days at each of the eight North American Longitudinal Prodrome Study sites. Tests derived from generalizability theory showed excellent reliability in the amygdala (Eρ2=0.82), inferior frontal gyrus (IFG;Eρ2=0.83), anterior cingulate cortex (ACC;Eρ2=0.76), insula (Eρ2=0.85), and fusiform gyrus (Eρ2=0.91) for maximum activation and fair to excellent reliability in the amygdala (Eρ2=0.44), IFG (Eρ2=0.48), ACC (Eρ2=0.55), insula (Eρ2=0.42), and fusiform gyrus (Eρ2=0.83) for mean activation across sites and test days. For the amygdala, habituation (Eρ2=0.71) was more stable than mean activation. In a second investigation, data from 111 healthy individuals across sites were aggregated in a voxelwise, quantitative meta-analysis. When compared with a mixed effects model controlling for site, both approaches identified robust activation in regions consistent with expected results based on prior single-site research. Overall, regions central to emotion processing showed strong reliability in the traveling participants study and robust activation in the aggregation study. These results support the reliability of blood oxygen level-dependent signal in emotion processing areas across different sites and scanners and may inform future efforts to increase efficiency and enhance knowledge of rare conditions in the population through multisite neuroimaging paradigms. PMID:25821147

Exposure to pesticide as a risk factor for depression: A population-based longitudinal study in Korea.

PubMed

Koh, Sang-Baek; Kim, Tae Hui; Min, Seongho; Lee, Kyungsuk; Kang, Dae Ryong; Choi, Jung Ran

2017-09-01

Exposure to pesticides is associated with mental disorders, including depression, especially among occupationally exposed populations, such as farmers. The results of experimental studies ascribed the negative effects of pesticides on mental health to their neurotoxic and endocrine-disrupting activities. This study aimed to investigate the association between the risk of depression and high- or low-level exposure to pesticides in a rural population. This longitudinal study was performed in 2005-2008 (baseline) and 2008-2012 (follow-up) to evaluate the risk of depression among 2151 Korean adults. A standardized questionnaire was used to obtain information on depression upon self-reported exposure to pesticide based on the Center for Epidemiologic Studies Depression Scale. Logistic regression analysis was performed to evaluate the association between pesticide exposure and depression. We adjusted the data for age, cigarette smoking status, current alcohol use, monthly income, educational level, marriage status, and religion. Among the individuals who reported depression, the number of participants who used pesticides was significantly higher than that who did not (N=61 [7.2%] vs. N=54 [4.2%], P=0.003). A positive association was noted between >20-year period of pesticide use and depression (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.41-3.88). Individuals who reported depression showed greater odds of being exposed to higher pesticide concentrations (OR, 2.33; 95% CI, 1.40-3.88) and experiencing pesticide poisoning (OR, 5.83; 95% CI, 1.80-18.86) than those who did not. Exposure to pesticides at a high concentration was found to be associated with depressive symptoms among Korean adults. Copyright © 2017 Elsevier B.V. All rights reserved.

Validity of the ATP III diagnostic criteria for the metabolic syndrome in an elderly Italian Caucasian population: the Italian Longitudinal Study on Aging.

PubMed

Maggi, Stefania; Noale, Marianna; Zambon, Alberto; Limongi, Federica; Romanato, Giovanna; Crepaldi, Gaetano

2008-04-01

The metabolic syndrome (MetS) is represented by the co-occurrence of multiple metabolic and physiologic risk factors for both type 2 diabetes mellitus and atherosclerotic cardiovascular diseases. In spite of its high frequency and association with morbidity and mortality in the adult population, very little is known about its magnitude in the elderly and about the validity of the diagnostic criteria commonly used. The objective of this paper is to assess the prevalence rate of MetS and the validity of the Adult Treatment Panel III (ATP III) diagnostic criteria in an elderly Caucasian cohort, considering data from the Italian Longitudinal Study on Aging (ILSA), a population-based study with a sample of 5632 individuals aged 65-84 years at baseline (1992). Logistic regression models and ROC curve were used to test the validity of the cut off levels proposed. The prevalence of MetS was 31.5% in men, and 59.8% in women. The cut off levels suggested for both men and women by the ATP III panel indicated a significant association with the MetS for all components. Actually, the ROC analysis would suggest lower levels for glycaemia (106 mg/dl) in men, and higher levels for blood pressure in both men and women (145/95 and 135/90, respectively). Concluding, MetS is very common in the aged Caucasians and the diagnostic criteria proposed by the ATP III panel seem to be appropriate in older individuals. Small adjustments in the cut off levels could be suggested for glycaemia (men) and in blood pressure (men and women).

Prevalence and correlates of diagnosed and undiagnosed type 2 diabetes mellitus and pre-diabetes in older adults: Findings from the Irish Longitudinal Study on Ageing (TILDA).

PubMed

Leahy, S; O' Halloran, A M; O' Leary, N; Healy, M; McCormack, M; Kenny, R A; O' Connell, J

2015-12-01

The prevalence of type 2 diabetes and pre-diabetes has increased rapidly in recent decades and this trend will continue as the global population ages. This study investigates the prevalence of, and factors associated with, diagnosed and undiagnosed type 2 diabetes mellitus and pre-diabetes in older adults in Ireland. Cross-sectional data from 5377 men and women aged 50 and over from Wave 1 of the Irish Longitudinal Study on Ageing (TILDA) was analysed. Diagnosed diabetes was defined using self-reported doctors' diagnosis and medications data. Glycated haemoglobin (HbA1c) analysis was used to identify undiagnosed and pre-diabetes. Age and sex-specific prevalence estimates were generated. Logistic regression was used to investigate the association between diabetes classification and the demographic, health and lifestyle characteristics of the population. The prevalence of diagnosed and undiagnosed type 2 diabetes was 8.6% (95% confidence interval (CI): 7.6-9.5%) and 0.9% (95% CI: 0.6-1.1%) respectively. Diabetes was more prevalent in men than women and increased with age. The prevalence of pre-diabetes was 5.5% (95% CI: 4.8-6.3%) and increased with age. Diabetes and pre-diabetes were independently associated with male sex, central obesity and a history of hypertension, while undiagnosed diabetes was associated with geographic location and medical costs cover. Despite high rates of obesity and other undiagnosed health conditions, the prevalence of undiagnosed and pre-diabetes is relatively low in community-dwelling older adults in Ireland. Addressing lifestyle factors in this population may help to further reduce the prevalence of pre-diabetes and improve outcomes for those with a previous diagnosis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Effect of neighbourhood deprivation and social cohesion on mental health inequality: a multilevel population-based longitudinal study.

PubMed

Fone, D; White, J; Farewell, D; Kelly, M; John, G; Lloyd, K; Williams, G; Dunstan, F

2014-08-01

The common mental disorders (CMDs) of anxiety and depression are the most common form of poor mental health in the general population. Evidence from the small number of previous cohort studies on the role of neighbourhood factors in mental health is inconclusive. We tested the hypothesis that high levels of neighbourhood social cohesion modify an adverse association between change in individual mental health and neighbourhood deprivation. We carried out a longitudinal multilevel analysis using data from the Caerphilly Health and Social Needs Cohort Study with a 7-year follow-up (n = 4426; age range 18-74 years at baseline). Neighbourhood deprivation and neighbourhood social cohesion were assessed at baseline and change in mental health between follow-up and baseline was assessed using the five-item Mental Health Inventory (MHI-5). Residence in the most deprived neighbourhoods was negatively associated with change in mental health, after adjusting for baseline individual socio-economic risk factors and transitions in life events. This negative effect was significantly reduced in high social cohesion neighbourhoods. The predicted change in mental health score was calculated for the 10th and 90th centiles of the household low-income distribution. The difference between them was -2.8 in the low social cohesion group and 1.1 in the high cohesion group. The difference between the groups was 3.9 [95% confidence interval (CI) 0.2-7.6]. The public health burden of poor mental health and mental health inequality could potentially be reduced by strengthening social cohesion in deprived neighbourhoods. This offers a mechanism to address the adverse effect of neighbourhood deprivation on population mental health.

Changes in Crohn's disease phenotype over time in the Chinese population: validation of the Montreal classification system.

PubMed

Chow, Dorothy K L; Leong, Rupert W L; Lai, Larry H; Wong, Grace L H; Leung, Wai-Keung; Chan, Francis K L; Sung, Joseph J Y

2008-04-01

Phenotypic evolution of Crohn's disease occurs in whites but has never been described in other populations. The Montreal classification may describe phenotypes more precisely. The aim of this study was to validate the Montreal classification through a longitudinal sensitivity analysis in detecting phenotypic variation compared to the Vienna classification. This was a retrospective longitudinal study of consecutive Chinese Crohn's disease patients. All cases were classified by the Montreal classification and the Vienna classification for behavior and location. The evolution of these characteristics and the need for surgery were evaluated. A total of 109 patients were recruited (median follow-up: 4 years, range: 6 months-18 years). Crohn's disease behavior changed 3 years after diagnosis (P = 0.025), with an increase in stricturing and penetrating phenotypes, as determined by the Montreal classification, but was only detected by the Vienna classification after 5 years (P = 0.015). Disease location remained stable on follow-up in both classifications. Thirty-four patients (31%) underwent major surgery during the follow-up period with the stricturing [P = 0.002; hazard ratio (HR): 3.3; 95% CI: 1.5-7.0] and penetrating (P = 0.03; HR: 5.8; 95% CI: 1.2-28.2) phenotypes according to the Montreal classification associated with the need for major surgery. In contrast, colonic disease was protective against a major operation (P = 0.02; HR: 0.3; 95% CI: 0.08-0.8). This is the first study demonstrating phenotypic evolution of Crohn's disease in a nonwhite population. The Montreal classification is more sensitive to behavior phenotypic changes than is the Vienna classification after excluding perianal disease from the penetrating disease category and was useful in predicting course and the need for surgery.

Dietary patterns and cardiovascular risk factors in adolescents and young adults: the Northern Ireland Young Hearts Project.

PubMed

McCourt, Hannah J; Draffin, Claire R; Woodside, Jayne V; Cardwell, Chris R; Young, Ian S; Hunter, Steven J; Murray, Liam J; Boreham, Colin A; Gallagher, Alison M; Neville, Charlotte E; McKinley, Michelle C

2014-11-28

Dietary pattern (DP) analysis allows examination of the combined effects of nutrients and foods on the markers of CVD. Very few studies have examined these relationships during adolescence or young adulthood. Traditional CVD risk biomarkers were analysed in 12-15-year-olds (n 487; Young Hearts (YH)1) and again in the same individuals at 20-25 years of age (n 487; YH3). Based on 7 d diet histories, in the present study, DP analysis was performed using a posteriori principal component analysis for the YH3 cohort and the a priori Mediterranean Diet Score (MDS) was calculated for both YH1 and YH3 cohorts. In the a posteriori DP analysis, YH3 participants adhering most closely to the 'healthy' DP were found to have lower pulse wave velocity (PWV) and homocysteine concentrations, the 'sweet tooth' DP were found to have increased LDL concentrations, and decreased HDL concentrations, [corrected] the 'drinker/social' DP were found to have lower LDL and homocysteine concentrations, but exhibited a trend towards a higher TAG concentration, and finally the 'Western' DP were found to have elevated homocysteine and HDL concentrations. In the a priori dietary score analysis, YH3 participants adhering most closely to the Mediterranean diet were found to exhibit a trend towards a lower PWV. MDS did not track between YH1 and YH3, and nor was there a longitudinal relationship between the change in the MDS and the change in CVD risk biomarkers. In conclusion, cross-sectional analysis revealed that some associations between DP and CVD risk biomarkers were already evident in the young adult population, namely the association between the healthy DP (and the MDS) and PWV; however, no longitudinal associations were observed between these relatively short time periods.

Social connections and happiness among the elder population of Taiwan.

PubMed

Hsu, H-C; Chang, W-C

2015-01-01

The purpose of this study was to examine the association between social connections and happiness among members of the elder population of Taiwan. Longitudinal panel data collected in three waves from 1999 to 2007 that are selected from national samples of Taiwanese older people were used for the analysis (n = 4731 persons). Happiness was defined as a dichotomous variable. Social connection variables included living arrangements, contacts with children/grandchildren/parents/relatives/friends, telephone contacts, providing instrumental and informational support, receiving instrumental and emotional support, and social participation. We controlled for the variables demographics, physical and mental health, economic satisfaction, and lifestyle. A generalized linear model (GLM) was applied in the analysis. Happiness remained stable over time. Receiving more emotional support and participating in social events were related to happiness at the beginning, while the effect of social participation was offset over time. Living arrangements, telephone contacts, providing social support, and receiving instrumental support were not significant. The quality of social relationships experienced is possibly more important than the quantity of social interaction for older people, and having social relationships outside the informal social network may increase happiness.

Occupational exposure and risk of chronic obstructive pulmonary disease: a systematic review and meta-analysis.

PubMed

Alif, Sheikh M; Dharmage, Shyamali C; Bowatte, Gayan; Karahalios, Amalia; Benke, Geza; Dennekamp, Martine; Mehta, Amar J; Miedinger, David; Künzli, Nino; Probst-Hensch, Nicole; Matheson, Melanie C

2016-08-01

Due to contradictory literature we have performed a systematic review and meta-analyse of population-based studies that have used Job Exposure Matrices to assess occupational exposure and risk of Chronic Obstructive Pulmonary Disease (COPD). Two researchers independently searched databases for published articles using predefined inclusion criteria. Study quality was assessed, and results pooled for COPD and chronic bronchitis for exposure to biological dust, mineral dust, and gases/fumes using a fixed and random effect model. Five studies met predetermined inclusion criteria. The meta-analysis showed low exposure to mineral dust, and high exposure to gases/fumes were associated with an increased risk of COPD. We also found significantly increased the risk of chronic bronchitis for low and high exposure to biological dust and mineral dust. Expert commentary: The relationship between occupational exposure assessed by the JEM and the risk of COPD and chronic bronchitis shows significant association with occupational exposure. However, the heterogeneity of the meta-analyses suggests more wide population-based studies with older age groups and longitudinal phenotype assessment of COPD to clarify the role of occupational exposure to COPD risk.

User’s Guide for the Longitudinal Scalogram Analysis Program

DTIC Science & Technology

1991-01-01

cannabis, pills, psychedelics , cocaine, and heroin. The LSA analysis was restricted to these respondents (n = 791), because complete information about...Total n = 791. 0 = not passed, I = passed. Items am legal drugs, cannabis, pills, psychedelics , cocaine, and heroin. Asterisks denote longitudinal

Medical resource use and expenditure in patients with chronic heart failure: a population-based analysis of 88 195 patients.

PubMed

Farré, Nuria; Vela, Emili; Clèries, Montse; Bustins, Montse; Cainzos-Achirica, Miguel; Enjuanes, Cristina; Moliner, Pedro; Ruiz, Sonia; Verdú-Rotellar, Jose Maria; Comín-Colet, Josep

2016-09-01

Heart failure (HF) is one of the diseases with greater healthcare expenditure. However, little is known about the cost of HF at a population level. Hence, our aim was to study the population-level distribution and predictors of healthcare expenditure in patients with HF. This was a population-based longitudinal study including all prevalent HF cases in Catalonia (Spain) on 31 December 2012 (n = 88 195). We evaluated 1-year healthcare resource use and expenditure using the Health Department (CatSalut) surveillance system that collects detailed information on healthcare usage for the entire population. Mean age was 77.4 (12) years; 55% were women. One-year mortality rate was 14%. All-cause emergency department visits and unplanned hospitalizations were required at least once in 53.4% and 30.8% of patients, respectively. During 2013, a total of €536.2 million were spent in the care of HF patients (7.1% of the total healthcare budget). The main source of expenditure was hospitalization (39% of the total) whereas outpatient care represented 20% of the total expenditure. In the general population, outpatient care and hospitalization were the main expenses. In multivariate analysis, younger age, higher presence of co-morbidities, and a recent HF or all-cause hospitalization were independently associated with higher healthcare expenditure. In Catalonia, a large portion of the annual healthcare budget is devoted to HF patients. Unplanned hospitalization represents the main source of healthcare-related expenditure. The knowledge of how expenditure is distributed in a non-selected HF population might allow health providers to plan the distribution of resources in patients with HF. © 2016 The Authors. European Journal of Heart Failure © 2016 European Society of Cardiology.

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.

Longitudinal Change and Stability of Refractive, Keratometric, and Internal Astigmatism in Childhood

PubMed Central

Harvey, Erin M.; Miller, Joseph M.; Twelker, J. Daniel; Sherrill, Duane L.

2015-01-01

Purpose. To assess longitudinal change in refractive, keratometric, and internal astigmatism in a sample of students from a population with a high prevalence of with-the-rule (WTR) astigmatism and to determine the optical origins of changes in refractive astigmatism. Methods. A retrospective analysis of longitudinal measurements of right eye refractive and keratometric astigmatism in Tohono O'odham Native American children was conducted. Changes in refractive and keratometric astigmatism per year were compared in a younger cohort (n = 1594, 3 to <11 years old) and an older cohort (n = 648, 11 to <19 years old). Data were analyzed in clinical notation (Cyl) and vector notation (J0, J45). Results. On average, refractive astigmatism (means: 1.19 diopters [D] Cyl, +0.54 J0, +0.03 J45) resulted primarily from WTR corneal astigmatism (means: +0.85 J0, −0.02 J45) and against-the-rule (ATR) internal astigmatism (means: −0.31 J0, +0.05 J45). Mean longitudinal changes in astigmatism were statistically significant (younger cohort −0.02 D/y Cyl; older cohort +0.06 D/y Cyl). In the younger cohort, astigmatism decreased with age in low and moderate astigmats (<3.00 D) and increased with age in high astigmats (≥3.00 D). In the older cohort, astigmatism increased with age across all levels of astigmatism. Longitudinal changes in keratometric and internal astigmatism were negatively correlated in both cohorts. Conclusions. Cross-sectional data suggest the presence of a constant ATR contribution from internal astigmatism (0.60 D Cyl) that is close to the 0.50 D ATR constant reported by Javal and others. Highly astigmatic 3- to <11-year-old children and children older than age 11 years show a small (not clinically significant) increase in astigmatism with age. A negative correlation between changes in keratometric astigmatism and internal astigmatism suggests an active compensation that may contribute to the stability of astigmatism in Tohono O'odham children. PMID:25515577

Progressive brain changes in children and adolescents with early-onset psychosis: A meta-analysis of longitudinal MRI studies.

PubMed

Fraguas, David; Díaz-Caneja, Covadonga M; Pina-Camacho, Laura; Janssen, Joost; Arango, Celso

2016-06-01

Studies on longitudinal brain volume changes in patients with early-onset psychosis (EOP) are particularly valuable for understanding the neurobiological basis of brain abnormalities associated with psychosis. However, findings have not been consistent across studies in this population. We aimed to conduct a meta-analysis on progressive brain volume changes in children and adolescents with EOP. A systematic literature search of magnetic resonance imaging (MRI) studies comparing longitudinal brain volume changes in children and adolescents with EOP and healthy controls was conducted. The annualized rates of relative change in brain volume by region of interest (ROI) were used as raw data for the meta-analysis. The effect of age, sex, duration of illness, and specific diagnosis on volume change was also evaluated. Five original studies with 156 EOP patients (mean age at baseline MRI in the five studies ranged from 13.3 to 16.6years, 67.31% males) and 163 age- and sex-matched healthy controls, with a mean duration of follow-up of 2.46years (range 2.02-3.40), were included. Frontal gray matter (GM) was the only region in which significant differences in volume change over time were found between patients and controls (Hedges' g -0.435, 95% confidence interval (CI): -0.678 to -0.193, p<0.001). Younger age at baseline MRI was associated with greater loss of temporal GM volume over time in patients as compared with controls (p=0.005). Within patients, a diagnosis of schizophrenia was related to greater occipital GM volume loss over time (p=0.001). Compared with healthy individuals, EOP patients show greater progressive frontal GM loss over the first few years after illness onset. Age at baseline MRI and diagnosis of schizophrenia appear to be significant moderators of particular specific brain volume changes. Copyright © 2014 Elsevier B.V. All rights reserved.

Inequality and adolescent violence: an exploration of community, family, and individual factors.

PubMed Central

Bruce, Marino A.

2004-01-01

PURPOSE: The study seeks to examine whether the relationships among community, family, individual factors, and violent behavior are parallel across race- and gender-specific segments of the adolescent population. METHODS: Data from the National Longitudinal Study of Adolescent Health are analyzed to highlight the complex relationships between inequality, community, family, individual behavior, and violence. RESULTS: The results from robust regression analysis provide evidence that social environmental factors can influence adolescent violence in race- and gender-specific ways. CONCLUSIONS: Findings from this study establish the plausibility of multidimensional models that specify a complex relationship between inequality and adolescent violence. PMID:15101669

Contribution of the polarization moments of different rank to the integral CPT signal

NASA Astrophysics Data System (ADS)

Taskova, E.; Alipieva, E.; Todorov, G.

2016-01-01

In the present work we investigate the relation of the polarization moments having different ranks with the tensor components which form the observable integral CPT signal, in the presence of a stray magnetic field. A numerical experiment with parameters close to the real ones is performed, using a program based on the irreducible tensor operator formalism1. The integral fluorescent signal is calculated for the non-polarized fluorescence at different laser power excitation. Detailed analysis of the numerical solutions for all tensor components which describe population and alignment allows visualizing the dynamics of their behavior in dependence on the experimental geometry and laboratory magnetic field B'. The dependence of population f00, longitudinal f02 and transverse f22 alignment in the presence of transverse magnetic field is investigated. The shape and sign of the resonance change with laser power.

Homelessness and Housing Insecurity Among Former Prisoners

PubMed Central

HERBERT, CLAIRE W.; MORENOFF, JEFFREY D.; HARDING, DAVID J.

2016-01-01

The United States has experienced dramatic increases in both incarceration rates and the population of insecurely housed or homeless persons since the 1980s. These marginalized populations have strong overlaps, with many people being poor, minority, and from an urban area. That a relationship between homelessness, housing insecurity, and incarceration exists is clear, but the extent and nature of this relationship is not yet adequately understood. We use longitudinal, administrative data on Michigan parolees released in 2003 to examine returning prisoners’ experiences with housing insecurity and homelessness. Our analysis finds relatively low rates of outright homelessness among former prisoners, but very high rates of housing insecurity, much of which is linked to features of community supervision, such as intermediate sanctions, returns to prison, and absconding. We identify risk factors for housing insecurity, including mental illness, substance use, prior incarceration, and homelessness, as well as protective “buffers” against insecurity and homelessness, including earnings and social supports. PMID:26913294

Arsenic exposure and oral cavity lesions in Bangladesh.

PubMed

Syed, Emdadul H; Melkonian, Stephanie; Poudel, Krishna C; Yasuoka, Junko; Otsuka, Keiko; Ahmed, Alauddin; Islam, Tariqul; Parvez, Faruque; Slavkovich, Vesna; Graziano, Joseph H; Ahsan, Habibul; Jimba, Masamine

2013-01-01

To evaluate the relationship between arsenic exposure and oral cavity lesions among an arsenic-exposed population in Bangladesh. We carried out an analysis utilizing the baseline data of the Health Effects of Arsenic Exposure Longitudinal Study, which is an ongoing population-based cohort study to investigate health outcomes associated with arsenic exposure via drinking water in Araihazar, Bangladesh. We used multinomial regression models to estimate the risk of oral cavity lesions. Participants with high urinary arsenic levels (286.1 to 5000.0 μg/g) were more likely to develop arsenical lesions of the gums (multinomial odds ratio = 2.90; 95% confidence interval, 1.11 to 7.54), and tongue (multinomial odds ratio = 2.79; 95% confidence interval, 1.51 to 5.15), compared with those with urinary arsenic levels of 7.0 to 134.0 μg/g. Higher level of arsenic exposure was positively associated with increased arsenical lesions of the gums and tongue.

Resilience in the Disabling Effect of Gait Speed Among Older Turkish and Moroccan Immigrants and Native Dutch.

PubMed

Klokgieters, Silvia S; van Tilburg, Theo G; Deeg, Dorly J H; Huisman, Martijn

2018-06-01

To investigate the factors that inhibit the disabling effect of impairments among citizens who have migrated from Turkey and Morocco and native Dutch according to a resilience perspective. Using data from the Longitudinal Aging Study Amsterdam with 928 native Dutch, 255 Turks, and 199 Moroccans aged 55 to 65, linear regression analysis assessed whether country of origin, mastery, income, and contact frequency modified the relationship between gait speed and activity limitations. Turks, but not Moroccans, demonstrated stronger associations between gait speed and activity limitations than the Dutch. Mastery modified the association among the Dutch and the Turks. Income modified the association only among the Dutch. Effect modification by contact frequency was not observed. Moroccans and Dutch appeared to be more resilient against impairments than Turks. As none of the resilience factors buffered in all three populations, we conclude that resilience mechanisms are not universal across populations.

Preliminary Rural Analysis of the Early Childhood Longitudinal Study--Kindergarten Cohort. Rural Early Childhood Brief Number 2

ERIC Educational Resources Information Center

National Center for Rural Early Childhood Learning Initiatives - Mississippi State University Early Childhood Institute, 2005

2005-01-01

This brief introduces the first results from a rural analysis of selected national datasets. Provided are key findings concerning kindergarten readiness of rural children from an analysis of the Kindergarten Cohort of the Early Childhood Longitudinal Study (ECLS). Future briefs will summarize the findings concerning the health of the Kindergarten…

Measuring molecular biomarkers in epidemiologic studies: laboratory techniques and biospecimen considerations.

PubMed

Erickson, Heidi S

2012-09-28

The future of personalized medicine depends on the ability to efficiently and rapidly elucidate a reliable set of disease-specific molecular biomarkers. High-throughput molecular biomarker analysis methods have been developed to identify disease risk, diagnostic, prognostic, and therapeutic targets in human clinical samples. Currently, high throughput screening allows us to analyze thousands of markers from one sample or one marker from thousands of samples and will eventually allow us to analyze thousands of markers from thousands of samples. Unfortunately, the inherent nature of current high throughput methodologies, clinical specimens, and cost of analysis is often prohibitive for extensive high throughput biomarker analysis. This review summarizes the current state of high throughput biomarker screening of clinical specimens applicable to genetic epidemiology and longitudinal population-based studies with a focus on considerations related to biospecimens, laboratory techniques, and sample pooling. Copyright © 2012 John Wiley & Sons, Ltd.

Investigating the historic long-term population health impact of the US National School Lunch Program.

PubMed

Peterson, Cora

2014-12-01

The present research aimed to compare historic participation in the US National School Lunch Program (NSLP) during childhood and subsequent prevalence of overweight and obesity among adults at the population level. Regression models examined cross-sectional, state- and age-based panel data constructed from multiple sources, including the Behavioural Risk Factor Surveillance System, US Congressional Record, US Census and the US Department of Agriculture. Models controlled for cohorts' racial/ethnic composition and state poverty rates. Adult-age cohorts (18-34, 35-49, 50-64 and 18-64 years) by US state over a 25-year period (1984-2008). The cohorts' prevalence of overweight and obesity was compared with the cohorts' estimated NSLP participation during schooling (1925-2007; the NSLP began in 1946). Among adults aged 18-64 years, a one percentage-point increase in estimated NSLP participation during schooling between 1925 and 2007 was significantly associated with a 0·29 percentage-point increase in the cohort's later prevalence of overweight and obesity. Analysis of narrower age cohorts and different schooling periods produced mixed results. The NSLP might have influenced population health historically. Longitudinal analysis of individuals from studies now underway will likely facilitate more robust conclusions about the NSLP's long-term health impact based on more recent experiences.

Mortality trajectory analysis reveals the drivers of sex-specific epidemiology in natural wildlife–disease interactions

PubMed Central

McDonald, Jennifer L.; Smith, Graham C.; McDonald, Robbie A.; Delahay, Richard J.; Hodgson, Dave

2014-01-01

In animal populations, males are commonly more susceptible to disease-induced mortality than females. However, three competing mechanisms can cause this sex bias: weak males may simultaneously be more prone to exposure to infection and mortality; being ‘male’ may be an imperfect proxy for the underlying driver of disease-induced mortality; or males may experience increased severity of disease-induced effects compared with females. Here, we infer the drivers of sex-specific epidemiology by decomposing fixed mortality rates into mortality trajectories and comparing their parameters. We applied Bayesian survival trajectory analysis to a 22-year longitudinal study of a population of badgers (Meles meles) naturally infected with bovine tuberculosis (bTB). At the point of infection, infected male and female badgers had equal mortality risk, refuting the hypothesis that acquisition of infection occurs in males with coincidentally high mortality. Males and females exhibited similar levels of heterogeneity in mortality risk, refuting the hypothesis that maleness is only a proxy for disease susceptibility. Instead, sex differences were caused by a more rapid increase in male mortality rates following infection. Males are indeed more susceptible to bTB, probably due to immunological differences between the sexes. We recommend this mortality trajectory approach for the study of infection in animal populations. PMID:25056621

Mortality level and predictors in a rural Ethiopian population: community based longitudinal study.

PubMed

Weldearegawi, Berhe; Spigt, Mark; Berhane, Yemane; Dinant, Geertjan

2014-01-01

Over the last fifty years the world has seen enormous decline in mortality rates. However, in low-income countries, where vital registration systems are absent, mortality statistics are not easily available. The recent economic growth of Ethiopia and the parallel large scale healthcare investments make investigating mortality figures worthwhile. Longitudinal health and demographic surveillance data collected from September 11, 2009 to September 10, 2012 were analysed. We computed incidence of mortality, overall and stratified by background variables. Poisson regression was used to test for a linear trend in the standardized mortality rates. Cox-regression analysis was used to identify predictors of mortality. Households located at <2300 meter and ≥ 2300 meter altitude were defined to be midland and highland, respectively. An open cohort, with a baseline population of 66,438 individuals, was followed for three years to generate 194,083 person-years of observation. The crude mortality rate was 4.04 (95% CI: 3.77, 4.34) per 1,000 person-years. During the follow-up period, incidence of mortality significantly declined among under five (P<0.001) and 5-14 years old (P<0.001), whereas it increased among 65 years and above (P<0.001). Adjusted for other covariates, mortality was higher in males (hazard ratio (HR) = 1.42, 95% CI: 1.22, 1.66), rural population (HR = 1.74, 95% CI: 1.32, 2.31), highland (HR = 1.20, 95% CI: 1.03, 1.40) and among those widowed (HR = 2.25, 95% CI: 1.81, 2.80) and divorced (HR = 1.80, 95% CI: 1.30, 2.48). Overall mortality rate was low. The level and patterns of mortality indicate changes in the epidemiology of major causes of death. Certain population groups had significantly higher mortality rates and further research is warranted to identify causes of higher mortality in those groups.

Cross-Sectional and Longitudinal Associations between Serum Bilirubin and Prediabetes in a Health Screening Population.

PubMed

Oda, Eiji

2016-06-01

Longitudinal associations between total bilirubin (TB) and prediabetes have not been reported. This study investigated cross-sectional and longitudinal associations between TB and prediabetes. Cross-sectional associations between TB and prediabetes were investigated in 3681 nondiabetic subjects. Longitudinal associations between TB and prediabetes over 6 years were investigated in 2149 subjects who were normoglycemic at baseline. Prediabetes was defined as fasting plasma glucose (FPG) levels of ≥5.6 mmol/L or glycated hemoglobin levels of ≥5.7% excluding diabetes. The prevalence of prediabetes was 25.4%, and the cumulative incidence of prediabetes during 6 years was 25.5% in a Japanese health screening population. Prevalent prediabetes was significantly associated with the quintiles of TB in nonsmoking men (trend, p<0.001) and women (trend, p=0.012), but not in smoking men (trend, p=0.689). Incident prediabetes was not significantly associated with the quintiles of TB, while it was positively associated with 1 standard deviation increase in TB in nonsmoking men (hazard ratio [95% confidence interval]; 1.21 [1.07 to 1.37], p=0.002). TB levels were significantly inversely associated with prevalent prediabetes in nonsmokers, but not in smokers, whereas an inverse association between TB levels and incident prediabetes seemed to be unlikely. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

A Proposed Approach for Joint Modeling of the Longitudinal and Time-To-Event Data in Heterogeneous Populations: An Application to HIV/AIDS's Disease.

PubMed

Roustaei, Narges; Ayatollahi, Seyyed Mohammad Taghi; Zare, Najaf

2018-01-01

In recent years, the joint models have been widely used for modeling the longitudinal and time-to-event data simultaneously. In this study, we proposed an approach (PA) to study the longitudinal and survival outcomes simultaneously in heterogeneous populations. PA relaxes the assumption of conditional independence (CI). We also compared PA with joint latent class model (JLCM) and separate approach (SA) for various sample sizes (150, 300, and 600) and different association parameters (0, 0.2, and 0.5). The average bias of parameters estimation (AB-PE), average SE of parameters estimation (ASE-PE), and coverage probability of the 95% confidence interval (CP) among the three approaches were compared. In most cases, when the sample sizes increased, AB-PE and ASE-PE decreased for the three approaches, and CP got closer to the nominal level of 0.95. When there was a considerable association, PA in comparison with SA and JLCM performed better in the sense that PA had the smallest AB-PE and ASE-PE for the longitudinal submodel among the three approaches for the small and moderate sample sizes. Moreover, JLCM was desirable for the none-association and the large sample size. Finally, the evaluated approaches were applied on a real HIV/AIDS dataset for validation, and the results were compared.

Patient-Related Benefits for Adults with Cochlear Implantation: A Multicultural Longitudinal Observational Study

PubMed Central

Lenarz, Thomas; Muller, Lida; Czerniejewska-Wolska, Hanna; Vallés Varela, Hector; Orús Dotú, César; Durko, Marcin; Huarte Irujo, Alicia; Piszczatowski, Bartosz; Zadrożniak, Marek; Irwin, Colin; Graham, Petra L.; Wyss, Josie

2017-01-01

Objectives To assess subjectively perceived, real-world benefits longitudinally for unilateral cochlear implant (CI) recipients in a multinational population treated routinely. To identify possible predictors of self-reported benefits. Design This was a prospective, multicenter, repeated-measures study. Self-assessment of performance at preimplantation and postimplantation at 1, 2, and 3 years using standardized, validated, local language versions of the Speech, Spatial, and Qualities of Hearing Scale (SSQ), and the Health Utilities Index Mark 3 (HUI3) was performed. Outcomes were analyzed using a longitudinal mixed-effects model incorporating country effect. Patient demographics were explored for associations with change over time. Subjects Two hundred ninety-one routinely treated, unilateral CI recipients, aged 137–81 years, from 9 clinics across 4 countries. Results Highly significant improvements were observed for all outcome measures (p < 0.0001). Postimplantation, mean outcome scores remained stable beyond 1 year, with notable individual variability. A significant association for one or more outcomes with preimplantation contralateral hearing aid use, telephone use, age at implantation, implantation side, preimplantation comorbidities, dizziness, and tinnitus was observed (p < 0.004). Conclusions Longitudinal benefits of CI treatment can be measured using clinically standardized self-assessment tools to provide a holistic view of patient-related benefits in routine clinical practice for aggregated data from multinational populations. Self-reported outcomes can provide medical-based evidence regarding CI treatment to support decision-making by health service providers. PMID:28719901

Tissue Probability Map Constrained 4-D Clustering Algorithm for Increased Accuracy and Robustness in Serial MR Brain Image Segmentation

PubMed Central

Xue, Zhong; Shen, Dinggang; Li, Hai; Wong, Stephen

2010-01-01

The traditional fuzzy clustering algorithm and its extensions have been successfully applied in medical image segmentation. However, because of the variability of tissues and anatomical structures, the clustering results might be biased by the tissue population and intensity differences. For example, clustering-based algorithms tend to over-segment white matter tissues of MR brain images. To solve this problem, we introduce a tissue probability map constrained clustering algorithm and apply it to serial MR brain image segmentation, i.e., a series of 3-D MR brain images of the same subject at different time points. Using the new serial image segmentation algorithm in the framework of the CLASSIC framework, which iteratively segments the images and estimates the longitudinal deformations, we improved both accuracy and robustness for serial image computing, and at the mean time produced longitudinally consistent segmentation and stable measures. In the algorithm, the tissue probability maps consist of both the population-based and subject-specific segmentation priors. Experimental study using both simulated longitudinal MR brain data and the Alzheimer’s Disease Neuroimaging Initiative (ADNI) data confirmed that using both priors more accurate and robust segmentation results can be obtained. The proposed algorithm can be applied in longitudinal follow up studies of MR brain imaging with subtle morphological changes for neurological disorders. PMID:26566399

Whole-Genome Sequencing and Variant Analysis of Human Papillomavirus 16 Infections.

PubMed

van der Weele, Pascal; Meijer, Chris J L M; King, Audrey J

2017-10-01

Human papillomavirus (HPV) is a strongly conserved DNA virus, high-risk types of which can cause cervical cancer in persistent infections. The most common type found in HPV-attributable cancer is HPV16, which can be subdivided into four lineages (A to D) with different carcinogenic properties. Studies have shown HPV16 sequence diversity in different geographical areas, but only limited information is available regarding HPV16 diversity within a population, especially at the whole-genome level. We analyzed HPV16 major variant diversity and conservation in persistent infections and performed a single nucleotide polymorphism (SNP) comparison between persistent and clearing infections. Materials were obtained in the Netherlands from a cohort study with longitudinal follow-up for up to 3 years. Our analysis shows a remarkably large variant diversity in the population. Whole-genome sequences were obtained for 57 persistent and 59 clearing HPV16 infections, resulting in 109 unique variants. Interestingly, persistent infections were completely conserved through time. One reinfection event was identified where the initial and follow-up samples clustered differently. Non-A1/A2 variants seemed to clear preferentially ( P = 0.02). Our analysis shows that population-wide HPV16 sequence diversity is very large. In persistent infections, the HPV16 sequence was fully conserved. Sequencing can identify HPV16 reinfections, although occurrence is rare. SNP comparison identified no strongly acting effect of the viral genome affecting HPV16 infection clearance or persistence in up to 3 years of follow-up. These findings suggest the progression of an early HPV16 infection could be host related. IMPORTANCE Human papillomavirus 16 (HPV16) is the predominant type found in cervical cancer. Progression of initial infection to cervical cancer has been linked to sequence properties; however, knowledge of variants circulating in European populations, especially with longitudinal follow-up, is limited. By sequencing a number of infections with known follow-up for up to 3 years, we gained initial insights into the genetic diversity of HPV16 and the effects of the viral genome on the persistence of infections. A SNP comparison between sequences obtained from clearing and persistent infections did not identify strongly acting DNA variations responsible for these infection outcomes. In addition, we identified an HPV16 reinfection event where sequencing of initial and follow-up samples showed different HPV16 variants. Based on conventional genotyping, this infection would incorrectly be considered a persistent HPV16 infection. In the context of vaccine efficacy and monitoring studies, such infections could potentially cause reduced reported efficacy or efficiency. Copyright © 2017 van der Weele et al.

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.

Association of Genetic Risk for Schizophrenia With Nonparticipation Over Time in a Population-Based Cohort Study.

PubMed

Martin, Joanna; Tilling, Kate; Hubbard, Leon; Stergiakouli, Evie; Thapar, Anita; Davey Smith, George; O'Donovan, Michael C; Zammit, Stanley

2016-06-15

Progress has recently been made in understanding the genetic basis of schizophrenia and other psychiatric disorders. Longitudinal studies are complicated by participant dropout, which could be related to the presence of psychiatric problems and associated genetic risk. We tested whether common genetic variants implicated in schizophrenia were associated with study nonparticipation among 7,867 children and 7,850 mothers from the Avon Longitudinal Study of Parents and Children (ALSPAC; 1991-2007), a longitudinal population cohort study. Higher polygenic risk scores for schizophrenia were consistently associated with noncompletion of questionnaires by study mothers and children and nonattendance at data collection throughout childhood and adolescence (ages 1-15 years). These associations persisted after adjustment for other potential correlates of nonparticipation. Results suggest that persons at higher genetic risk for schizophrenia are likely to be underrepresented in cohort studies, which will underestimate risk of this and related psychiatric, cognitive, and behavioral phenotypes in the population. Statistical power to detect associations with these phenotypes will be reduced, while analyses of schizophrenia-related phenotypes as outcomes may be biased by the nonrandom missingness of these phenotypes, even if multiple imputation is used. Similarly, in complete-case analyses, collider bias may affect associations between genetic risk and other factors associated with missingness. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Accounting for the dead in the longitudinal analysis of income-related health inequalities

PubMed Central

Petrie, Dennis; Allanson, Paul; Gerdtham, Ulf-G.

2011-01-01

This paper develops an accounting framework to consider the effect of deaths on the longitudinal analysis of income-related health inequalities. Ignoring deaths or using Inverse Probability Weights (IPWs) to re-weight the sample for mortality-related attrition can produce misleading results. Incorporating deaths into the longitudinal analysis of income-related health inequalities provides a more complete picture in terms of the evaluation of health changes in respect to socioeconomic status. We illustrate our work by investigating health mobility from 1999 till 2004 using the British Household Panel Survey (BHPS). We show that for Scottish males explicitly accounting for the dead rather than using IPWs to account for mortality-related attrition changes the direction of the relationship between relative health changes and initial income position, from negative to positive, while for other groups it significantly increases the strength of the positive relationship. Incorporating the dead may be vital in the longitudinal analysis of health inequalities. PMID:21820193

Accounting for the dead in the longitudinal analysis of income-related health inequalities.

PubMed

Petrie, Dennis; Allanson, Paul; Gerdtham, Ulf G

2011-09-01

This paper develops an accounting framework to consider the effect of deaths on the longitudinal analysis of income-related health inequalities. Ignoring deaths or using Inverse Probability Weights (IPWs) to re-weight the sample for mortality-related attrition can produce misleading results. Incorporating deaths into the longitudinal analysis of income-related health inequalities provides a more complete picture in terms of the evaluation of health changes in respect to socioeconomic status. We illustrate our work by investigating health mobility from 1999 till 2004 using the British Household Panel Survey (BHPS). We show that for Scottish males explicitly accounting for the dead rather than using IPWs to account for mortality-related attrition changes the direction of the relationship between relative health changes and initial income position, from negative to positive, while for other groups it significantly increases the strength of the positive relationship. Incorporating the dead may be vital in the longitudinal analysis of health inequalities. Copyright © 2011 Elsevier B.V. All rights reserved.

Genetic differentiation among migrant and resident populations of the threatened Asian houbara bustard.

PubMed

Riou, Samuel; Combreau, Olivier; Judas, Jacky; Lawrence, Mark; Al Baidani, Mohamed Saleh; Pitra, Christian

2012-01-01

The Asian houbara bustard Chlamydotis macqueenii is a partial migrant of conservation concern found in deserts of central Asia and the Middle East. In the southern part of the species range, resident populations have been greatly fragmented and reduced by sustained human pressure. In the north, birds migrate from breeding grounds between West Kazakhstan and Mongolia to wintering areas in the Middle East and south central Asia. Extensive satellite tracking has shown substantial partitioning in migration routes and wintering grounds, suggesting a longitudinal barrier to present-day gene flow among migrants. In this context, we explored genetic population structure using 17 microsatellite loci and sampling 108 individuals across the range. We identified limited but significant overall differentiation (F(CT) = 0.045), which was overwhelmingly due to the differentiation of resident Arabian populations, particularly the one from Yemen, relative to the central Asian populations. Population structure within the central Asian group was not detectable with the exception of subtle differentiation of West Kazakh birds on the western flyway, relative to eastern populations. We interpret these patterns as evidence of recent common ancestry in Asia, coupled with a longitudinal barrier to present-day gene flow along the migratory divide, which has yet to translate into genetic divergence. These results provide key parameters for a coherent conservation strategy aimed at preserving genetic diversity and migration routes.

Public Housing Relocations and Relationships of Changes in Neighborhood Disadvantage and Transportation Access to Unmet Need for Medical Care.

PubMed

Haley, Danielle F; Linton, Sabriya; Luo, Ruiyan; Hunter-Jones, Josalin; Adimora, Adaora A; Wingood, Gina M; Bonney, Loida; Ross, Zev; Cooper, Hannah L

2017-01-01

Cross-sectional research suggests that neighborhood characteristics and transportation access shape unmet need for medical care. This longitudinal analysis explores relationships of changes in neighborhood socioeconomic disadvantage and trans- portation access to unmet need for medical care. We analyzed seven waves of data from African American adults (N = 172) relocating from severely distressed public housing complexes in Atlanta, Georgia. Surveys yielded individual-level data and admin- istrative data characterized census tracts. We used hierarchical generalized linear models to explore relationships. Unmet need declined from 25% pre-relocation to 12% at Wave 7. Post-relocation reductions in neighborhood disadvantage were inversely associated with reductions in unmet need over time (OR = 0.71, 95% CI = 0.51-0.99). More frequent transportation barriers predicted unmet need (OR = 1.16, 95% CI = 1.02-1.31). These longitudinal findings support the importance of neighborhood environments and transportation access in shaping unmet need and suggest that improvements in these exposures reduce unmet need for medical care in this vulnerable population.

Public Housing Relocations and Relationships of Changes in Neighborhood Disadvantage and Transportation Access to Unmet Need for Medical Care

PubMed Central

Haley, Danielle F.; Linton, Sabriya; Luo, Ruiyan; Hunter-Jones, Josalin; Adimora, Adaora A.; Wingood, Gina M.; Bonney, Loida; Ross, Zev; Cooper, Hannah L.F.

2017-01-01

Introduction Cross-sectional research suggests that neighborhood characteristics and transportation access shape unmet need for medical care. This longitudinal analysis explores relationships of changes in neighborhood socioeconomic disadvantage and transportation access to unmet need for medical care. Methods We analyzed seven waves of data from African American adults (N = 172) relocating from severely distressed public housing complexes in Atlanta, Georgia. Surveys yielded individual-level data and administrative data characterized census tracts. We used hierarchical generalized linear models to explore relationships. Results Unmet need declined from 25% pre-relocation to 12% at Wave 7. Post-relocation reductions in neighborhood disadvantage were inversely associated with reductions in unmet need over time (OR = 0.71, 95% CI = 0.51–0.99). More frequent transportation barriers predicted unmet need (OR = 1.16, 95% CI = 1.02–1.31). Conclusion These longitudinal findings support the importance of neighborhood environments and transportation access in shaping unmet need and suggest that improvements in these exposures reduce unmet need for medical care in this vulnerable population. PMID:28239005

Left ventricular myocardial velocities and deformation indexes in top-level athletes.

PubMed

D'Andrea, Antonello; Cocchia, Rosangela; Riegler, Lucia; Scarafile, Raffaella; Salerno, Gemma; Gravino, Rita; Golia, Enrica; Pezzullo, Enrica; Citro, Rodolfo; Limongelli, Giuseppe; Pacileo, Giuseppe; Cuomo, Sergio; Caso, Pio; Russo, Maria Giovanna; Bossone, Eduardo; Calabrò, Raffaele

2010-12-01

The aim of this study was to define the range of left ventricular (LV) velocities and deformation indexes in highly trained athletes, analyzing potential differences induced by different long-term training protocols. Standard echocardiography, pulsed-wave tissue Doppler echocardiography, and two-dimensional strain echocardiography of the interventricular septum and lateral wall were performed in 370 endurance athletes and 280 power athletes. Using pulsed-wave tissue Doppler, the following parameters of myocardial function were assessed: systolic peak velocities (S(m)), early (E(m)) and late (A(m)) diastolic velocities, and the E(m)/A(m) ratio. By two-dimensional strain echocardiography, peaks of regional systolic strain and LV global longitudinal strain were calculated. LV mass index and ejection fraction did not significantly differ between the two groups. However, power athletes showed an increased sum of wall thicknesses (P < .01) and relative wall thickness, while LV stroke volume and LV end-diastolic diameter (P < .001) were greater in endurance athletes. By pulsed-wave tissue Doppler analysis, E(m) and E(m)/A(m) at both the septal and lateral wall levels were higher in endurance athletes. By two-dimensional strain echocardiography, myocardial deformation indexes were comparable between the two groups. E(m)/A(m) ratios ≥ 1 were found in the overall population, while 90 % of athletes had an E(m) ≥ 16 cm/sec, S(m) ≥ 10 cm/sec, and global longitudinal strain ≤ -16%. Multivariate analyses evidenced independent positive association between Em peak velocity and LV end-diastolic volume (P < .001) and an independent correlation of global longitudinal strain with the sum of LV wall thicknesses (P < .005). This study describes the full spectrum of systolic and diastolic myocardial velocities and deformation indexes in a large population of competitive athletes. Copyright © 2010 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

Does relationship satisfaction and financial aid from offspring influence the quality of life of older parents?: a longitudinal study based on findings from the Korean longitudinal study of aging, 2006-2012.

PubMed

Ju, Yeong Jun; Han, Kyu-Tae; Lee, Tae-Hoon; Kim, Woorim; Kim, Juyeong; Park, Eun-Cheol

2016-07-26

Quality of life (QoL) in old age is of major importance because the global population is aging rapidly. Offspring support, including financial and emotional support, is important in later life and directly affects the wellbeing of elderly individuals. The aim of this study was to examine the relationship between QoL in older parents and offspring support. We used baseline data from the 2006-2012 Korean Longitudinal Study of Aging, from 3,274 individuals aged 65 years or older. We measured the individual's QoL using a visual analog scale and included both relationship satisfaction and regular economic support as variables. A generalized estimating equation (GEE) model was used to perform longitudinal regression analysis on the data. Regarding the QoL of older parents, those with an unsatisfying relationship with their offspring had a QoL of -21.93 (SE = 0.55; P < 0.0001) compared to those with satisfying offspring relationships. Those receiving no regular financial aid from their offspring had a QoL of -0.92 (SE = 0.38; P = 0.0171) compared to those who received such economic support. Combination effects were observed, with cases living alone - and having poor offspring relationships and no regular financial support from their offspring - showing the most drastic decrease in QoL (-23.46; SE = 1.03; P < 0.0001). Offspring support influences the QoL of elderly individuals, and Korean children appear to play a crucial role in the QoL of their (older) parents. Considering that the role of offspring is rapidly diminishing due to industrialization policies, initiatives are required to revitalize offspring support for elderly parents.

Early detection of cardiac involvement in sarcoidosis with 2-dimensional speckle-tracking echocardiography.

PubMed

Schouver, Elie-Dan; Moceri, Pamela; Doyen, Denis; Tieulie, Nathalie; Queyrel, Viviane; Baudouy, Delphine; Cerboni, Pierre; Gibelin, Pierre; Leroy, Sylvie; Fuzibet, Jean-Gabriel; Ferrari, Emile

2017-01-15

Cardiac sarcoidosis (CS) is associated with high morbidity and sudden death. The absence of specific symptoms and lack of diagnostic gold standard technique is challenging. New imaging methods could improve the diagnosis of CS. The aim of our study was to assess the role of left ventricular (LV) longitudinal and circumferential strain as estimated by 2D speckle-tracking imaging in patients with diagnosed sarcoidosis without cardiac involvement according to the current guidelines. We investigated the prevalence of LV strain impairment in this population and assessed its relationship with clinical outcomes, composite of mortality, heart failure, arrhythmia and/or secondarily development of CS and cardiac device implantation. We performed a prospective case-control longitudinal study including 35 patients with diagnosed sarcoidosis and normal cardiac function as assessed by standard transthoracic echocardiography and 35 healthy age- and gender-matched controls. All patients underwent a comprehensive echocardiographic study. Mean age of patients was 47.9±14.8years old (22 women). Compared with controls, global LV longitudinal strain (LV GLS) was reduced in sarcoidosis patients: (-17.2±3.1 vs -21.3±1.5%, p<0.0001). Circumferential LV strain was preserved in patients compared to controls (-19.9±-4.3% vs -21.3±1.5%, p=0.12). Impaired LV GLS was significantly associated with clinical outcomes (HR 1.56; [1.16-2.11], p<0.01) on univariate analysis. Speckle-tracking echocardiography revealed decreased longitudinal LV strain in sarcoidosis patients that was associated with outcomes. LV GLS may represent an early marker of myocardial involvement in sarcoidosis patients that needs to be studied further. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Temporal patterns of variable relationships in person-oriented research: longitudinal models of configural frequency analysis.

PubMed

von Eye, Alexander; Mun, Eun Young; Bogat, G Anne

2008-03-01

This article reviews the premises of configural frequency analysis (CFA), including methods of choosing significance tests and base models, as well as protecting alpha, and discusses why CFA is a useful approach when conducting longitudinal person-oriented research. CFA operates at the manifest variable level. Longitudinal CFA seeks to identify those temporal patterns that stand out as more frequent (CFA types) or less frequent (CFA antitypes) than expected with reference to a base model. A base model that has been used frequently in CFA applications, prediction CFA, and a new base model, auto-association CFA, are discussed for analysis of cross-classifications of longitudinal data. The former base model takes the associations among predictors and among criteria into account. The latter takes the auto-associations among repeatedly observed variables into account. Application examples of each are given using data from a longitudinal study of domestic violence. It is demonstrated that CFA results are not redundant with results from log-linear modeling or multinomial regression and that, of these approaches, CFA shows particular utility when conducting person-oriented research.

Coexistence and Within-Host Evolution of Diversified Lineages of Hypermutable Pseudomonas aeruginosa in Long-term Cystic Fibrosis Infections

PubMed Central

Feliziani, Sofía; Moyano, Alejandro J.; Di Rienzo, Julio A.; Krogh Johansen, Helle; Molin, Søren; Smania, Andrea M.

2014-01-01

The advent of high-throughput sequencing techniques has made it possible to follow the genomic evolution of pathogenic bacteria by comparing longitudinally collected bacteria sampled from human hosts. Such studies in the context of chronic airway infections by Pseudomonas aeruginosa in cystic fibrosis (CF) patients have indicated high bacterial population diversity. Such diversity may be driven by hypermutability resulting from DNA mismatch repair system (MRS) deficiency, a common trait evolved by P. aeruginosa strains in CF infections. No studies to date have utilized whole-genome sequencing to investigate within-host population diversity or long-term evolution of mutators in CF airways. We sequenced the genomes of 13 and 14 isolates of P. aeruginosa mutator populations from an Argentinian and a Danish CF patient, respectively. Our collection of isolates spanned 6 and 20 years of patient infection history, respectively. We sequenced 11 isolates from a single sample from each patient to allow in-depth analysis of population diversity. Each patient was infected by clonal populations of bacteria that were dominated by mutators. The in vivo mutation rate of the populations was ∼100 SNPs/year–∼40-fold higher than rates in normo-mutable populations. Comparison of the genomes of 11 isolates from the same sample showed extensive within-patient genomic diversification; the populations were composed of different sub-lineages that had coexisted for many years since the initial colonization of the patient. Analysis of the mutations identified genes that underwent convergent evolution across lineages and sub-lineages, suggesting that the genes were targeted by mutation to optimize pathogenic fitness. Parallel evolution was observed in reduction of overall catabolic capacity of the populations. These findings are useful for understanding the evolution of pathogen populations and identifying new targets for control of chronic infections. PMID:25330091

Multivariate Analysis of Longitudinal Rates of Change

PubMed Central

Bryan, Matthew; Heagerty, Patrick J.

2016-01-01

Longitudinal data allow direct comparison of the change in patient outcomes associated with treatment or exposure. Frequently, several longitudinal measures are collected that either reflect a common underlying health status, or characterize processes that are influenced in a similar way by covariates such as exposure or demographic characteristics. Statistical methods that can combine multivariate response variables into common measures of covariate effects have been proposed by Roy and Lin [1]; Proust-Lima, Letenneur and Jacqmin-Gadda [2]; and Gray and Brookmeyer [3] among others. Current methods for characterizing the relationship between covariates and the rate of change in multivariate outcomes are limited to select models. For example, Gray and Brookmeyer [3] introduce an “accelerated time” method which assumes that covariates rescale time in longitudinal models for disease progression. In this manuscript we detail an alternative multivariate model formulation that directly structures longitudinal rates of change, and that permits a common covariate effect across multiple outcomes. We detail maximum likelihood estimation for a multivariate longitudinal mixed model. We show via asymptotic calculations the potential gain in power that may be achieved with a common analysis of multiple outcomes. We apply the proposed methods to the analysis of a trivariate outcome for infant growth and compare rates of change for HIV infected and uninfected infants. PMID:27417129

The Longitudinal Interplay of Maternal Warmth and Adolescents' Self-Disclosure in Predicting Maternal Knowledge

ERIC Educational Resources Information Center

Blodgett Salafia, Elizabeth H.; Gondoli, Dawn M.; Grundy, Amber M.

2009-01-01

This study examined the longitudinal associations among maternal warmth, adolescents' self-disclosure, and maternal knowledge during the transition to adolescence. Three years of self-report data were collected from 131 married mothers and their adolescents. Results from longitudinal analysis using adolescent reports indicated that greater…

Multivariate Longitudinal Methods for Studying Developmental Relationships between Depression and Academic Achievement

ERIC Educational Resources Information Center

Grimm, Kevin J.

2007-01-01

Recent advances in methods and computer software for longitudinal data analysis have pushed researchers to more critically examine developmental theories. In turn, researchers have also begun to push longitudinal methods by asking more complex developmental questions. One such question involves the relationships between two developmental…

Identifying reprioritization response shift in a stroke caregiver population: a comparison of missing data methods.

PubMed

Sajobi, Tolulope T; Lix, Lisa M; Singh, Gurbakhshash; Lowerison, Mark; Engbers, Jordan; Mayo, Nancy E

2015-03-01

Response shift (RS) is an important phenomenon that influences the assessment of longitudinal changes in health-related quality of life (HRQOL) studies. Given that RS effects are often small, missing data due to attrition or item non-response can contribute to failure to detect RS effects. Since missing data are often encountered in longitudinal HRQOL data, effective strategies to deal with missing data are important to consider. This study aims to compare different imputation methods on the detection of reprioritization RS in the HRQOL of caregivers of stroke survivors. Data were from a Canadian multi-center longitudinal study of caregivers of stroke survivors over a one-year period. The Stroke Impact Scale physical function score at baseline, with a cutoff of 75, was used to measure patient stroke severity for the reprioritization RS analysis. Mean imputation, likelihood-based expectation-maximization imputation, and multiple imputation methods were compared in test procedures based on changes in relative importance weights to detect RS in SF-36 domains over a 6-month period. Monte Carlo simulation methods were used to compare the statistical powers of relative importance test procedures for detecting RS in incomplete longitudinal data under different missing data mechanisms and imputation methods. Of the 409 caregivers, 15.9 and 31.3 % of them had missing data at baseline and 6 months, respectively. There were no statistically significant changes in relative importance weights on any of the domains when complete-case analysis was adopted. But statistical significant changes were detected on physical functioning and/or vitality domains when mean imputation or EM imputation was adopted. There were also statistically significant changes in relative importance weights for physical functioning, mental health, and vitality domains when multiple imputation method was adopted. Our simulations revealed that relative importance test procedures were least powerful under complete-case analysis method and most powerful when a mean imputation or multiple imputation method was adopted for missing data, regardless of the missing data mechanism and proportion of missing data. Test procedures based on relative importance measures are sensitive to the type and amount of missing data and imputation method. Relative importance test procedures based on mean imputation and multiple imputation are recommended for detecting RS in incomplete data.

International Spotlight: Israel

PubMed Central

Glicksman, Allen; Litwin, Howard

2011-01-01

The State of Israel provides significant opportunities to study social processes that can enhance our understanding of the aging experience. It has high life expectancy and rapid growth of its older population. With an older cohort that is composed largely of former immigrants and includes a minority Arab population, Israel provides much diversity for gerontological study. Among the unique issues facing older Israelis are the aging of Holocaust survivors, modernization in the Arab sector, and privatization in the kibbutzim. New legislation related to pensions and universal health care is expected to affect aging processes. The development of “supportive communities” offers a new service model. The article notes 2 longitudinal studies of importance—the Israeli component of the Survey of Health, Ageing, and Retirement in Europe and the Jerusalem Longitudinal Cohort Study. PMID:22038339

Are School-SES Effects Statistical Artefacts? Evidence from Longitudinal Population Data

ERIC Educational Resources Information Center

Marks, Gary N.

2015-01-01

Schools' socioeconomic status (SES) has been claimed as an important influence on student performance and there are calls for a policy response. However, there is an extensive literature which for various reasons casts doubt on the veracity of school-SES effects. This paper investigates school-SES effects with population data from a longitudinal…

Population Ecology (Organizational Ecology): An Experiential Exercise Demonstrating How Organizations in an Industry Are Born, Change, and Die

ERIC Educational Resources Information Center

MacMillan, Karen; Komar, Jennifer

2018-01-01

This article describes a classroom exercise that is designed to help students understand the basic tenets of population ecology (also known as organizational ecology). The macro-level, longitudinal approach to understanding organizations can be difficult for students to conceptualize as it involves systems thinking. This exercise makes the theory…

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…

A Population-Based Longitudinal Study of Depression in Children with Developmental Disabilities in Manitoba

ERIC Educational Resources Information Center

Shooshtari, Shahin; Brownell, Marni; Dik, Natalia; Chateau, Dan; Yu, C. T.; Mills, Rosemary S. L.; Burchill, Charles A.; Wetzel, Monika

2014-01-01

In this population-based study, prevalence of depression was estimated and compared between children with and without developmental disability (DD). Twelve years of administrative data were linked to identify a cohort of children with DD living in the Canadian province of Manitoba. Children in the study cohort were matched with children without DD…

Substance Use among Young Adults with Disabilities. Facts from NLTS2. NCSER 2008-3009

ERIC Educational Resources Information Center

Yu, Jennifer; Huang, Tracy; Newman, Lynn

2008-01-01

The report uses data from the National Longitudinal Transition Study-2 (NLTS2) to answer questions about the use of alcohol, cigarettes and illegal drugs such as marijuana, cocaine, and LSD among young adults with disabilities. The report compares substance use among this population with substance use in the general population, and compares…

Effects of College Experiences on Male and Female Student Leadership Capacity in Taiwan

ERIC Educational Resources Information Center

Wu, Ching-Ling

2011-01-01

This study examined how college experiences affect student leadership capacity in the general college population, as well as in male versus female populations. The data were drawn from a longitudinal sample of students across 156 colleges in Taiwan. Results of this study indicated that student leadership capacity increased after college entry.…

Conflict in Student Output Studies: National and State Needs vs. Local Management Needs.

ERIC Educational Resources Information Center

Lucas, John A.

In the past, almost all student follow-up studies have been cross institutional or very broad in nature. The target has consisted of populations of graduates, dropouts, or longitudinal entering classes. The output measures have centered around continued education of the population, job situation, mobility, reason for leaving, or a general…

Health-Related Quality of Life in Locally Advanced Cervical Cancer Patients After Definitive Chemoradiation Therapy Including Image Guided Adaptive Brachytherapy: An Analysis From the EMBRACE Study

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

Kirchheiner, Kathrin, E-mail: kathrin.kirchheiner@meduniwien.ac.at; Pötter, Richard; Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Vienna

Purpose: This study analyzed functioning and symptom scores for longitudinal quality of life (QoL) from patients with locally advanced cervical cancer who underwent definitive chemoradiation therapy with image guided adaptive brachytherapy in the EMBRACE study. Methods and Materials: In total, 744 patients at a median follow-up of 21 months were included. QoL was prospectively assessed using European Organization for Research and Treatment of Cancer Quality of Life core module 30 (EORTC QLQ-C30) and EORTC cervical cancer module 24 (CX24) questionnaires at baseline, then every 3 months during the first year, every 6 months in the second and third years, and finally yearly thereaftermore » in patients with no evidence of disease. Outcomes were evaluated over time and compared to those from an age-matched female reference population. Results: General QoL and emotional and social functioning were impaired at baseline but improved during the first 6 months after treatment, to reach a level comparable to that of the reference population, whereas cognitive functioning remained impaired. Both social and role functioning showed the lowest scores at baseline but which increased after treatment to reach a plateau at 6 months and then declined slightly at 3 and 4 years. The overall symptom experience was elevated at baseline and decreased to a level within the range of that of the reference population. Similarly, tumor-related symptoms (eg, pain, appetite loss, and constipation), which were present before treatment, decreased substantially at the first follow-up after treatment. Several treatment-related symptoms developed either immediately after and persisted over time (diarrhea, menopausal symptoms, peripheral neuropathy, and sexual functioning problems) or developed gradually after treatment (lymphedema and dyspnea). Conclusions: This longitudinal prospective QoL analysis showed that patients' general QoL and functioning were impaired before treatment compared to those of reference data. Several tumor-related symptoms resolved after treatment, and functioning and general QoL returned to that of the level of the reference population, indicating a transient impact of diagnosis and treatment. However, several treatment-related symptoms and problems did develop and persist, either immediately or gradually after treatment.« less

A Longitudinal Empirical Investigation of the Pathways Model of Problem Gambling.

PubMed

Allami, Youssef; Vitaro, Frank; Brendgen, Mara; Carbonneau, René; Lacourse, Éric; Tremblay, Richard E

2017-12-01

The pathways model of problem gambling suggests the existence of three developmental pathways to problem gambling, each differentiated by a set of predisposing biopsychosocial characteristics: behaviorally conditioned (BC), emotionally vulnerable (EV), and biologically vulnerable (BV) gamblers. This study examined the empirical validity of the Pathways Model among adolescents followed up to early adulthood. A prospective-longitudinal design was used, thus overcoming limitations of past studies that used concurrent or retrospective designs. Two samples were used: (1) a population sample of French-speaking adolescents (N = 1033) living in low socio-economic status (SES) neighborhoods from the Greater Region of Montreal (Quebec, Canada), and (2) a population sample of adolescents (N = 3017), representative of French-speaking students in Quebec. Only participants with at-risk or problem gambling by mid-adolescence or early adulthood were included in the main analysis (n = 180). Latent Profile Analyses were conducted to identify the optimal number of profiles, in accordance with participants' scores on a set of variables prescribed by the Pathways Model and measured during early adolescence: depression, anxiety, impulsivity, hyperactivity, antisocial/aggressive behavior, and drug problems. A four-profile model fit the data best. Three profiles differed from each other in ways consistent with the Pathways Model (i.e., BC, EV, and BV gamblers). A fourth profile emerged, resembling a combination of EV and BV gamblers. Four profiles of at-risk and problem gamblers were identified. Three of these profiles closely resemble those suggested by the Pathways Model.

A Comparison of Missing-Data Procedures for Arima Time-Series Analysis

ERIC Educational Resources Information Center

Velicer, Wayne F.; Colby, Suzanne M.

2005-01-01

Missing data are a common practical problem for longitudinal designs. Time-series analysis is a longitudinal method that involves a large number of observations on a single unit. Four different missing-data methods (deletion, mean substitution, mean of adjacent observations, and maximum likelihood estimation) were evaluated. Computer-generated…

Profiles of Intrinsic and Extrinsic Motivations in Elementary School: A Longitudinal Analysis

ERIC Educational Resources Information Center

Corpus, Jennifer Henderlong; Wormington, Stephanie V.

2014-01-01

The authors used a person-centered, longitudinal approach to identify and evaluate naturally occurring combinations of intrinsic and extrinsic motivations among 490 third- through fifth-grade students. Cluster analysis revealed 3 groups, characterized by high levels of both motivations ("high quantity"): high intrinsic motivation but low…

Issues in Longitudinal Research on Motivation

ERIC Educational Resources Information Center

Stoel, Reinoud D.; Roeleveld, Jaap; Peetsma, Thea; van den Wittenboer, Godfried; Hox, Joop

2006-01-01

This paper discusses two methodological issues regarding the analysis of longitudinal data using structural equation modeling that emerged during the reconsideration of the analysis of a recent study on the relationship between academic motivation and language achievement in elementary education [Stoel R.D., Peetsma, T.T.D. and Roeleveld, J.…

Age- and Sex-Related Influences on Left Ventricular Mechanics in Elderly Individuals Free of Prevalent Heart Failure: The ARIC Study (Atherosclerosis Risk in Communities).

PubMed

Hung, Chung-Lieh; Gonçalves, Alexandra; Shah, Amil M; Cheng, Susan; Kitzman, Dalane; Solomon, Scott D

2017-01-01

Advanced age is related to left ventricular (LV) remodeling. We sought to investigate the relationships between aging, elevated hemodynamic load, cardiac mechanics, and LV remodeling in an elderly community-based population. We studied 1105 subjects (76±5 years, 61% women) without prevalent heart failure, who attended the visit 5 of the ARIC study (Atherosclerosis Risk in Communities). LV global longitudinal strain, global circumferential strain, and torsion indices were analyzed using 3-dimensional echocardiography. Advanced age was associated with greater LV concentricity, lower myocardial diastolic relaxation, reduced global longitudinal strain (adjusted estimate, 0.39±0.19% (SE)/decade; P=0.038), borderline greater global circumferential strain (adjusted estimate, -0.59±0.36% (SE)/decade; P=0.08), and higher torsion indices (adjusted estimate for torsion, 0.33±0.04° (SE)/decade; P<0.001). In addition, greater concentricity was associated with decreased global longitudinal strain and greater torsion in multivariable models (all P<0.001). Women showed smaller LV cavity size, greater concentricity, lower myocardial relaxation velocity E', though demonstrated greater global longitudinal strain, global circumferential strain, and torsion than men (all P<0.05). Overall, subjects with hypertension and increasing age were more likely to have higher torsion, though the association between advanced age and greater torsion was more pronounced in women than in men (both interaction P<0.05). In an asymptomatic, senescent community-dwelling population, we observed a distinct, sex-specific pattern of cardiac remodeling. Although we observed worse diastolic and longitudinal function with advanced age or elevated load in both sexes, a significant increase of torsion was more pronounced in women. © 2017 American Heart Association, Inc.

Epidemiological evidence for the link between sleep duration and high blood pressure: a systematic review and meta-analysis.

PubMed

Guo, Xiaofan; Zheng, Liqiang; Wang, Jun; Zhang, Xiaoyu; Zhang, Xingang; Li, Jue; Sun, Yingxian

2013-04-01

We aim to assess if the relationship between short or long sleep duration and hypertension is present among adults from epidemiological evidence and to investigate the relationship quantitatively. We performed a comprehensive search of cross-sectional and longitudinal studies using PubMed and the Cochrane Library through February 2012. Our search was supplemented by reviewing reference lists of original and relevant reviews. After the related data were extracted by two investigators independently, pooled odds ratios (ORs) or relative risks (RRs) were estimated using a random-effects model or a fixed-effects model. Publication bias was evaluated, while sensitivity and meta-regression analyses were performed. Twenty-four adult studies met our inclusion criteria, with ages ranging from 18 to 106 years. Twenty-one studies involving 225,858 subjects were included in the meta-analysis. The pooled results from the cross-sectional studies showed that short sleep duration was associated with a greater risk for hypertension (OR, 1.21; 95% confidence interval [CI], 1.09-1.34; P<0.001), and long sleep duration also increased the risk for hypertension (OR, 1.11; 95% CI, 1.04-1.18; P=0.003). There was no evidence of publication bias. Pooled analysis from the longitudinal studies indicated a significant association between short sleep duration and hypertension (RR, 1.23; 95% CI, 1.06-1.42; P=0.005), but an insignificant relationship between long sleep duration and hypertension (RR, 1.02; 95% CI, 0.91-1.14; P=0.732). The effects of sleep duration differed by gender, location of the population, and definitions of short or long sleep duration. Meta regression analysis including seven variables did not find the sources of heterogeneity. Among adults, a U-shaped relationship between habitual sleep duration and hypertension was found at the cross-sectional level. Short sleep duration was associated with a higher risk for hypertension even longitudinally. We must pay more attention to this lifestyle factor. Copyright © 2012 Elsevier B.V. All rights reserved.

Validation of the Community Integration Questionnaire in the adult burn injury population.

PubMed

Gerrard, Paul; Kazis, Lewis E; Ryan, Colleen M; Shie, Vivian L; Holavanahalli, Radha; Lee, Austin; Jette, Alan; Fauerbach, James A; Esselman, Peter; Herndon, David; Schneider, Jeffrey C

2015-11-01

With improved survival, long-term effects of burn injuries on quality of life, particularly community integration, are important outcomes. This study aims to assess the Community Integration Questionnaire's psychometric properties in the adult burn population. Data were obtained from a multicenter longitudinal data set of burn survivors. The psychometric properties of the Community Integration Questionnaire (n = 492) were examined. The questionnaire items were evaluated for clinical and substantive relevance; validation procedures were conducted on different samples of the population; construct validity was assessed using exploratory factor analysis; internal consistency reliability was examined using Cronbach's α statistics; and item response theory was applied to the final models. The CIQ-15 was reduced by two questions to form the CIQ-13, with a two-factor structure, interpreted as self/family care and social integration. Item response theory testing suggests that Factor 2 captures a wider range of community integration levels. Cronbach's α was 0.80 for Factor 1, 0.77 for Factor 2, and 0.79 for the test as a whole. The CIQ-13 demonstrates validity and reliability in the adult burn survivor population addressing issues of self/family care and social integration. This instrument is useful in future research of community reintegration outcomes in the burn population.

Risk factors for human-directed canine aggression in a referral level clinical population.

PubMed

Lord, M; Casey, R A; Loftus, B A; Blackwell, E J

2017-07-07

Risk factors for human-directed aggression were investigated using retrospective analysis of data from a referral-level clinical behaviour population in the UK. A sample of 200 cases involving human-directed canine aggression and 200 control cases involving no instance of human-directed aggression were selected at random from a population of 746 cases. The final model suggested that clinical cases with human-directed aggression were significantly younger than those presenting with other undesired behaviours (P=0.008) and that male dogs were 1.4 times more likely to be aggressive towards human beings than female dogs (P=0.019). Dogs were 1.7 times more likely to be aggressive towards people if they had attended more than five puppy classes than if they had never attended puppy class (P=0.015) and that dogs were 2.8 times more likely to be aggressive towards human beings if there was another dog between 0 months and 24 months of age in the home (P=0.004). These factors only account for 7 per cent to 10 per cent of the variance between the human-directed aggression population and the control population, but factors such as attendance at puppy classes and numbers of dogs in the household suggest the need for longitudinal studies to investigate temporal relationships.

Genetic diversity and population structure of Plasmodium falciparum over space and time in an African archipelago.

PubMed

Salgueiro, Patrícia; Vicente, José Luís; Figueiredo, Rita Carrilho; Pinto, João

2016-09-01

The archipelago of São Tomé and Principe (STP), West Africa, has suffered the heavy burden of malaria since the 16th century. Until the last decade, when after a successful control program STP has become a low transmission country and one of the few nations with decreases of more than 90% in malaria admission and death rates. We carried out a longitudinal study to determine the genetic structure of STP parasite populations over time and space. Twelve microsatellite loci were genotyped in Plasmodium falciparum samples from two islands collected in 1997, 2000 and 2004. Analysis was performed on proportions of mixed genotype infections, allelic diversity, population differentiation, effective population size and bottleneck effects. We have found high levels of genetic diversity and minimal inter-population genetic differentiation typical of African continental regions with intense and stable malaria transmission. We detected significant differences between the years, with special emphasis for 1997 that showed the highest proportion of samples infected with P. falciparum and the highest mean number of haplotypes per isolate. This study establishes a comprehensive genetic data baseline of a pre-intervention scenario for future studies; taking into account the most recent and successful control intervention on the territory. Copyright © 2016 Elsevier B.V. All rights reserved.

The Association between Selenium and Lipid Levels: a Longitudinal Study in Rural Elderly Chinese

PubMed Central

Chen, Chen; Jin, Yinlong; Unverzagt, Frederick W.; Cheng, Yibin; Hake, Ann M.; Liang, Chaoke; Ma, Feng; Su, Liqin; Liu, Jingyi; Bian, Jianchao; Li, Ping; Gao, Sujuan

2014-01-01

A protective effect of selenium on lipid levels has been reported in populations with relatively low selenium status. However, recent studies found that high selenium exposure may lead to adverse cardiometabolic effects, particularly in selenium-replete populations. We examined the associations of selenium status with changes in lipid levels in a 7-year follow up of an elderly Chinese cohort including participants from selenium-deplete areas. Study population consisted of 140 elderly Chinese aged 65 or older with nail selenium levels measured at baseline (2003-2005). Lipid concentrations were measured in fasting blood samples collected at baseline and the 7-year follow-up (2010-2012). Analysis of covariance (ANCOVA) models was used to determine the association between baseline selenium status and changes in lipid levels from baseline to follow-up adjusting for other covariates. Mean (±standard deviation) baseline selenium concentration was 0.41±0.2mg/kg. In prospective analysis, we found that individuals in the highest selenium quartile group showed 1.11 SD decrease on total-cholesterol (p<0.001), 0.41 SD increase on HDL-cholesterol (p<0.001) and 0.52 SD decrease on triglyceride after 7 years than those in the lowest selenium quartile group. The similar trends were seen with significant lipids changes in the 2th and 3th quartile groups. Selenium has modestly beneficial effects on blood lipid levels in a population with relatively low selenium status. Our result suggests adequate dietary selenium intake as a potential prevention strategy for lowering lipid levels in selenium deplete populations. PMID:25263027

Trends in the location of the HIV-positive population in Australia: implications for access to healthcare services and delivery.

PubMed

Carman, Marina; Grierson, Jeffrey; Pitts, Marian; Hurley, Michael; Power, Jennifer

2010-06-01

Examining existing and potential trends in the HIV-positive population in Australia is important for current and future healthcare service development and delivery. A new analysis of existing data on this population from the HIV Futures 5 survey was based on linking a geographic breakdown of respondents based on 'area type'--capital city or inner suburban, outer suburban, regional centre and rural--with patterns of healthcare service access. In addition, the distance between the postcode of the respondent's residence and the postcode of the doctor seen for HIV-related treatment was calculated. An analysis of 'area type' by income and age was also conducted. The 'area type' analysis showed important differences in patterns of access to antiretroviral prescriptions and choice of provider for HIV-related and general healthcare. The median distance travelled to see a doctor for HIV-related treatment was higher for those living in outer suburbs than those living in regional centres. Differences in service use appear to be related to geographic accessibility of different service types. However, there may be other important social, economic and cultural factors involved. Ageing and socio-economic pressures may be influencing a move away from inner suburban areas where most HIV-specific care is located. This new analysis assists in finding the right balance between increasing the accessibility of HIV-specific services and 'mainstreaming'. Longitudinal data collection would further assist in tracking trends in geographic location, and how often and at what intervals people living with HIV utilise healthcare services.

Genetic Variation within a Lotic Population of Janthinobacterium lividum

PubMed Central

Saeger, Jennifer L.; Hale, Alan B.

1993-01-01

An understanding of the genetic variation within and between populations should allow scientists to address many problems, including those associated with endangered species and the release of genetically modified organisms into the environment. With respect to microorganisms, the release of genetically engineered microorganisms is likely to increase dramatically given the current growth in the bioremediation industry. In this study, genetic variation within a lotic, bacterial population of Janthinobacterium lividum was measured with restriction fragment length polymorphism analysis. Chromosomal DNA from 10 Kettle Creek (Hawk Mountain Sanctuary, Kempton, Pa.) J. lividum isolates was digested with six restriction endonucleases and probed with a 7.5-kb pKK3535 fragment containing the E. coli rrnB rRNA operon. Genetic variation, as measured in terms of nucleotide diversity, was high within the population. The 0.0781 value for genetic variation was especially high given the conservative nature of the genetic probe. The average percent similarity among isolates within the population was 67.25%. Pairwise comparisons of nucleotide diversity values (π) and similarity coefficients (F) yielded values ranging from 0.0032 to 0.1816 and 0.3363 to 0.9808, respectively. Putative clonemates were not present within the group of isolates; however, all isolates shared 14 fragments across a spectrum of six restriction enzymes. The presence of these common fragments indicates that restriction fragment length polymorphism analysis may provide population- or species-specific diagnostic markers for J. lividum. Data that suggest a plume effect with respect to the downstream movement of J. lividum are also presented. An increase in genetic variation within groups of isolates along the longitudinal gradient of Kettle Creek is also suggested. PMID:16348995

Genetic Variation within a Lotic Population of Janthinobacterium lividum.

PubMed

Saeger, J L; Hale, A B

1993-07-01

An understanding of the genetic variation within and between populations should allow scientists to address many problems, including those associated with endangered species and the release of genetically modified organisms into the environment. With respect to microorganisms, the release of genetically engineered microorganisms is likely to increase dramatically given the current growth in the bioremediation industry. In this study, genetic variation within a lotic, bacterial population of Janthinobacterium lividum was measured with restriction fragment length polymorphism analysis. Chromosomal DNA from 10 Kettle Creek (Hawk Mountain Sanctuary, Kempton, Pa.) J. lividum isolates was digested with six restriction endonucleases and probed with a 7.5-kb pKK3535 fragment containing the E. coli rrnB rRNA operon. Genetic variation, as measured in terms of nucleotide diversity, was high within the population. The 0.0781 value for genetic variation was especially high given the conservative nature of the genetic probe. The average percent similarity among isolates within the population was 67.25%. Pairwise comparisons of nucleotide diversity values (pi) and similarity coefficients (F) yielded values ranging from 0.0032 to 0.1816 and 0.3363 to 0.9808, respectively. Putative clonemates were not present within the group of isolates; however, all isolates shared 14 fragments across a spectrum of six restriction enzymes. The presence of these common fragments indicates that restriction fragment length polymorphism analysis may provide population- or species-specific diagnostic markers for J. lividum. Data that suggest a plume effect with respect to the downstream movement of J. lividum are also presented. An increase in genetic variation within groups of isolates along the longitudinal gradient of Kettle Creek is also suggested.

Applying the Nominal Response Model within a Longitudinal Framework to Construct the Positive Family Relationships Scale

ERIC Educational Resources Information Center

Preston, Kathleen Suzanne Johnson; Parral, Skye N.; Gottfried, Allen W.; Oliver, Pamella H.; Gottfried, Adele Eskeles; Ibrahim, Sirena M.; Delany, Danielle

2015-01-01

A psychometric analysis was conducted using the nominal response model under the item response theory framework to construct the Positive Family Relationships scale. Using data from the Fullerton Longitudinal Study, this scale was constructed within a long-term longitudinal framework spanning middle childhood through adolescence. Items tapping…

Training, Innovation and Business Performance: An Analysis of the Business Longitudinal Survey.

ERIC Educational Resources Information Center

Dockery, A. Michael

This paper uses the Australian Bureau of Statistics' Business Longitudinal Survey to explore relationships between training, innovation, and firm performance for Australian businesses with less than 200 employees. The longitudinal nature of the data is used to test various hypotheses about the nature of the link between training, business changes,…

Association of the Aspartate Aminotransferase to Alanine Aminotransferase Ratio with BNP Level and Cardiovascular Mortality in the General Population: The Yamagata Study 10-Year Follow-Up

PubMed Central

Yokoyama, Miyuki; Otaki, Yoichiro; Takahashi, Hiroki; Arimoto, Takanori; Shishido, Tetsuro; Miyamoto, Takuya; Konta, Tsuneo; Shibata, Yoko; Daimon, Makoto; Kayama, Takamasa; Kubota, Isao

2016-01-01

Background. Early identification of high risk subjects for cardiovascular disease in health check-up is still unmet medical need. Cardiovascular disease is characterized by the superior increase in aspartate aminotransferase (AST) to alanine aminotransferase (ALT). However, the association of AST/ALT ratio with brain natriuretic peptide (BNP) levels and cardiovascular mortality remains unclear in the general population. Methods and Results. This longitudinal cohort study included 3,494 Japanese subjects who participated in a community-based health check-up, with a 10-year follow-up. The AST/ALT ratio increased with increasing BNP levels. And multivariate logistic analysis showed that the AST/ALT ratio was significantly associated with a high BNP (≥100 pg/mL). There were 250 all-cause deaths including 79 cardiovascular deaths. Multivariate Cox proportional hazard regression analysis revealed that a high AST/ALT ratio (>90 percentile) was an independent predictor of all-cause and cardiovascular mortality after adjustment for confounding factors. Kaplan-Meier analysis demonstrated that cardiovascular mortality was higher in subjects with a high AST/ALT ratio than in those without. Conclusions. The AST/ALT ratio was associated with an increase in BNP and was predictive of cardiovascular mortality in a general population. Measuring the AST/ALT ratio during routine health check-ups may be a simple and cost-effective marker for cardiovascular mortality. PMID:27872510

Sequential Bottlenecks Drive Viral Evolution in Early Acute Hepatitis C Virus Infection

PubMed Central

McElroy, Kerensa; Gaudieri, Silvana; Pham, Son T.; Chopra, Abha; Cameron, Barbara; Maher, Lisa; Dore, Gregory J.; White, Peter A.; Lloyd, Andrew R.

2011-01-01

Hepatitis C is a pandemic human RNA virus, which commonly causes chronic infection and liver disease. The characterization of viral populations that successfully initiate infection, and also those that drive progression to chronicity is instrumental for understanding pathogenesis and vaccine design. A comprehensive and longitudinal analysis of the viral population was conducted in four subjects followed from very early acute infection to resolution of disease outcome. By means of next generation sequencing (NGS) and standard cloning/Sanger sequencing, genetic diversity and viral variants were quantified over the course of the infection at frequencies as low as 0.1%. Phylogenetic analysis of reassembled viral variants revealed acute infection was dominated by two sequential bottleneck events, irrespective of subsequent chronicity or clearance. The first bottleneck was associated with transmission, with one to two viral variants successfully establishing infection. The second occurred approximately 100 days post-infection, and was characterized by a decline in viral diversity. In the two subjects who developed chronic infection, this second bottleneck was followed by the emergence of a new viral population, which evolved from the founder variants via a selective sweep with fixation in a small number of mutated sites. The diversity at sites with non-synonymous mutation was higher in predicted cytotoxic T cell epitopes, suggesting immune-driven evolution. These results provide the first detailed analysis of early within-host evolution of HCV, indicating strong selective forces limit viral evolution in the acute phase of infection. PMID:21912520

Which language declines more? longitudinal versus cross-sectional decline of picture naming in bilinguals with Alzheimer's disease.

PubMed

Ivanova, Iva; Salmon, David P; Gollan, Tamar H

2014-05-01

In this study, we investigated dual-language decline in non-balanced bilinguals with probable Alzheimer's disease (AD) both longitudinally and cross-sectionally. We examined patients' naming accuracy on the Boston Naming Test (BNT: Kaplan et al., 1983) over three testing sessions (longitudinal analysis) and compared their performance to that of matched controls (cross-sectional analysis). We found different longitudinal and cross-sectional patterns of decline: Longitudinally, the non-dominant language seemed to decline more steeply than the dominant language, but, cross-sectionally, differences between patients and controls were larger for the dominant than for the non-dominant language, especially at the initial testing session. This differential pattern of results for cross-sectional versus longitudinal decline was supported by correlations between decline measures and BNT item characteristics. Further studies will be needed to better characterize the nature of linguistic decline in bilinguals with AD; however, these results suggest that representational robustness of individual lexical representations, rather than language membership, might determine the time course of decline for naming in bilinguals with AD.

An air brake model for longitudinal train dynamics studies

NASA Astrophysics Data System (ADS)

Wei, Wei; Hu, Yang; Wu, Qing; Zhao, Xubao; Zhang, Jun; Zhang, Yuan

2017-04-01

Experience of heavy haul train operation shows that heavy haul train fatigue fracture of coupler and its related components, even the accidents are caused by excessive coupler force. The most economical and effective method to study on train longitudinal impulse by reducing the coupler force is simulation method. The characteristics of train air brake system is an important excitation source for the study of longitudinal impulse. It is very difficult to obtain the braking characteristic by the test method, a better way to get the input parameters of the excitation source in the train longitudinal dynamics is modelling the train air brake system. In this paper, the air brake system model of integrated system of air brake and longitudinal dynamics is introduced. This introduce is focus on the locomotive automatic brake valve and vehicle distribution valve model, and the comparative analysis of the simulation and test results of the braking system is given. It is proved that the model can predict the characteristics of train braking system. This method provides a good solution for the excitation source of longitudinal dynamic analysis system.

Two-year changes in refractive error and related biometric factors in an adult Chinese population.

PubMed

He, Mingguang; Kong, Xiangbin; Chen, Qianyun; Zeng, Yangfa; Huang, Yuanzhou; Zhang, Jian; Morgan, Ian G; Meltzer, Mirjam E; Jin, Ling; Congdon, Nathan

2014-08-01

This article provides, to our knowledge, the first longitudinal population-based data on refractive error (RE) in Chinese persons. To study cohort effects and changes associated with aging in REs among Chinese adults. A 2-year, longitudinal population-based cohort study was conducted in southern China. Participants, identified using cluster random sampling, included residents of Yuexiu District, Guangzhou, China, aged 35 years or older who had undergone no previous eye surgery. Participants underwent noncycloplegic automated refraction and keratometry in December 2008 and December 2010; in a random 50% sample of the participants, anterior segment ocular coherence tomography measurement of lens thickness, as well as measurement of axial length and anterior chamber depth by partial coherence laser interferometry, were performed. Two-year change in spherical equivalent refraction (RE), lens thickness, axial length, and anterior chamber depth in the right eye. A total of 745 individuals underwent biometric testing in both 2008 and 2010 (2008 mean [SD] age, 52.2 [11.5] years; 53.7% women). Mean RE showed a 2-year hyperopic shift from -0.44 (2.21) to -0.31 (2.26) diopters (D) (difference, +0.13; 95% CI, 0.11 to 0.16). A consistent 2-year hyperopic shift of 0.09 to 0.22 D was observed among participants aged 35 to 64 years when stratifying by decade, suggesting that a substantial change in RE with aging may occur during this 30-year period. Cross-sectionally, RE increased only in the cohort younger than 50 years (0.11 D/y; 95% CI, 0.06 to 0.16). In the cross-sectional data, axial length decreased at -0.06 mm/y (95% CI, -0.09 to -0.04), although the 2-year change in axial length was positive and thus could not explain the cross-sectional difference. These latter results suggest a cohort effect, with greater myopia developing among younger persons. This first Chinese population-based longitudinal study of RE provides evidence for both important longitudinal aging changes and cohort effects, most notably greater myopia prevalence among younger persons.

The Lifetime Surveillance of Astronaut Health (LSAH) Project

NASA Technical Reports Server (NTRS)

Bopp, Eugenia; Wear, Mary L.; Lee, Lesley R.; VanBaalen, Mary

2013-01-01

From 1989-2010 NASA conducted a research study, the Longitudinal Study of Astronaut Health, to investigate the incidence of acute and chronic morbidity and mortality in astronauts and to determine whether their occupational exposures were associated with increased risk of death or disability. In 2004, the Institute of Medicine recommended that NASA convert the longitudinal study into an occupational health surveillance program and in 2010, NASA initiated the Lifetime Surveillance of Astronaut Health project. The new program collects data on astronaut workplace exposures, especially those occurring in the training and space flight environments, and conducts operational and health care analyses to look for trends in exposure and health outcomes. Astronaut selection and retention medical standards are rigorous, requiring an extensive clinical testing regimen. As a result, this employee population has contributed to a large set of health data available for analyses. Astronauts represent a special population with occupational exposures not typically experienced by other employee populations. Additionally, astronauts are different from the general population in terms of demographic and physiologic characteristics. The challenges and benefits of conducting health surveillance for an employee population with unique occupational exposures will be discussed. Several occupational surveillance projects currently underway to examine associations between astronaut workplace exposures and medical outcomes will be described.

Strategies for Longitudinal Analysis of the Career Paths of Beginning Teachers: Results from the First through Fourth Waves of the 2007-08 Beginning Teacher Longitudinal Study. Research and Development Report. NCES 2013-336

ERIC Educational Resources Information Center

Gray, Lucinda; Brauen, Marsha

2013-01-01

To learn more about the early career patterns of beginning teachers, the National Center for Education Statistics (NCES) of the Institute of Education Sciences within the U.S. Department of Education undertook the Beginning Teacher Longitudinal Study (BTLS). The ultimate purpose of this report is to develop a strategy for the longitudinal analysis…

Fast Genome-Wide QTL Association Mapping on Pedigree and Population Data.

PubMed

Zhou, Hua; Blangero, John; Dyer, Thomas D; Chan, Kei-Hang K; Lange, Kenneth; Sobel, Eric M

2017-04-01

Since most analysis software for genome-wide association studies (GWAS) currently exploit only unrelated individuals, there is a need for efficient applications that can handle general pedigree data or mixtures of both population and pedigree data. Even datasets thought to consist of only unrelated individuals may include cryptic relationships that can lead to false positives if not discovered and controlled for. In addition, family designs possess compelling advantages. They are better equipped to detect rare variants, control for population stratification, and facilitate the study of parent-of-origin effects. Pedigrees selected for extreme trait values often segregate a single gene with strong effect. Finally, many pedigrees are available as an important legacy from the era of linkage analysis. Unfortunately, pedigree likelihoods are notoriously hard to compute. In this paper, we reexamine the computational bottlenecks and implement ultra-fast pedigree-based GWAS analysis. Kinship coefficients can either be based on explicitly provided pedigrees or automatically estimated from dense markers. Our strategy (a) works for random sample data, pedigree data, or a mix of both; (b) entails no loss of power; (c) allows for any number of covariate adjustments, including correction for population stratification; (d) allows for testing SNPs under additive, dominant, and recessive models; and (e) accommodates both univariate and multivariate quantitative traits. On a typical personal computer (six CPU cores at 2.67 GHz), analyzing a univariate HDL (high-density lipoprotein) trait from the San Antonio Family Heart Study (935,392 SNPs on 1,388 individuals in 124 pedigrees) takes less than 2 min and 1.5 GB of memory. Complete multivariate QTL analysis of the three time-points of the longitudinal HDL multivariate trait takes less than 5 min and 1.5 GB of memory. The algorithm is implemented as the Ped-GWAS Analysis (Option 29) in the Mendel statistical genetics package, which is freely available for Macintosh, Linux, and Windows platforms from http://genetics.ucla.edu/software/mendel. © 2016 WILEY PERIODICALS, INC.

Recurrent respiratory papillomatosis: a longitudinal study comparing severity associated with human papilloma viral types 6 and 11 and other risk factors in a large pediatric population.

PubMed

Wiatrak, Brian J; Wiatrak, Deborah W; Broker, Thomas R; Lewis, Linda

2004-11-01

A database was developed for prospective, longitudinal study of recurrent respiratory papillomatosis (RRP) in a large population of pediatric patients. Data recorded for each patient included epidemiological factors, human papilloma virus (HPV) type, clinical course, staged severity of disease at each surgical intervention, and frequency of surgical intervention. The study hypothesizes that patients with HPV type 11 (HPV-11) and patients younger than 3 years of age at diagnosis are at risk for more aggressive and extensive disease. The 10-year prospective epidemiological study used disease staging for each patient with an original scoring system. Severity scores were updated at each surgical procedure. Parents of children with RRP referred to the authors' hospital completed a detailed epidemiological questionnaire at the initial visit or at the first return visit after the study began. At the first endoscopic debridement after study enrollment, tissue was obtained and submitted for HPV typing using polymerase chain reaction techniques and in situ hybridization. Staging of disease severity was performed in real time at each endoscopic procedure using an RRP scoring system developed by one of the authors (B.J.W.). The frequency of endoscopic operative debridement was recorded for each patient. Information in the database was analyzed to identify statistically significant relationships between extent of disease and/or HPV type, patient age at diagnosis, and selected epidemiological factors. The study may represent the first longitudinal prospective analysis of a large pediatric RRP population. Fifty-eight of the 73 patients in the study underwent HPV typing. Patients infected with HPV-11 were significantly more likely to have higher severity scores, require more frequent surgical intervention, and require adjuvant therapy to control disease progression. In addition, patients with HPV-11 RRP were significantly more likely to develop tracheal disease, to require tracheotomy, and to develop pulmonary disease. Patients receiving a diagnosis of RRP before 3 years of age had significantly higher severity scores, higher frequencies of surgical intervention, and greater likelihood of requiring adjuvant medical therapy. Patients with Medicaid insurance had significantly higher severity scores and required more frequent surgical debridement. Birth by cesarean section appeared to be a significant risk factor for more severe disease and necessity of more frequent surgical intervention. Statistical analysis of the relationships among epidemiological factors, HPV type, and clinical course revealed that patients with HPV-11 and patients younger than 3 years of age at RRP diagnosis are prone to develop more aggressive disease as represented by higher severity scores at endoscopic debridement, more frequent operative debridement procedures per year, a greater requirement for adjuvant therapy, and greater likelihood of tracheal disease with tracheotomy.

Anthropometry and blood pressure changes in a Caribbean adolescent population of African ancestry: an evaluation of longitudinal data using a multilevel mixed regression approach.

PubMed

Nichols, S; Cadogan, F

2012-10-01

The aim of this study was to determine the effect of growth pattern on blood pressure changes in an adolescent population of African ancestry based on longitudinal data and to compare this with estimates derived from cross-sectional data. Participants had measurements of weight, height, blood pressure and percentage body fat taken annually using standardized procedures. Annual blood pressure and anthropometry velocities as well as one- and three-year interval gender specific tracking coefficients were computed. We investigated whether changes in blood pressure could be explained by measures of growth using a multilevel mixed regression approach. The results showed that systolic blood pressure (SBP) increased by 1.27 and 3.09 mmHg per year among females and males, respectively. Similarly, diastolic blood pressure (DBP) increased by 1.16 and 1.92 mmHg per year among females and males, respectively. Multilevel analyses suggested that weight, body mass index, percentage body fat and height were the strongest anthropometric determinants of blood pressure change in this population. The results also suggest that there are gender differences in the relative importance of these anthropometric measures with height playing a minor role in predicting blood pressure changes among adolescent females. With the exception of DBP at 18 years among females, there were no significant differences between mean blood pressure generated from cross-sectional and longitudinal data by age in both males and females. Anthropometric measures are important covariates of age-related blood pressure changes and cross-sectional data may provide a more cost-effective and useful proxy for generating age-related blood pressure estimates in this population.

Long-term Quality of Life After Cytoreductive Surgery and Heated Intraperitoneal Chemotherapy for Pseudomyxoma Peritonei: A Prospective Longitudinal Study.

PubMed

Stearns, Adam T; Malcomson, Lee; Punnett, Grant; Abudeeb, Haytham; Aziz, Omer; Selvasekar, Chelliah R; Fulford, Paul E; Wilson, Malcolm S; Renehan, Andrew G; O'Dwyer, Sarah T

2018-04-01

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are an established treatment for pseudomyxoma peritonei (PMP), but it is a major surgical procedure and may be associated with long-term morbidity. To date, health-related quality-of-life (HRQL) data among survivors are lacking. A two-period qualitative study investigated patients undergoing CRS-HIPEC for PMP at a national peritoneal tumor center between 2003 and 2011. First, the European Organization for Research and Treatment (EORTC)-QLQ C30 HRQL questionnaire was used longitudinally preoperatively and at postoperative months 3, 6, 9, 12, 18, and 24, then yearly thereafter. Second, it was updated in 2016 as a cross-sectional study. Both studies were compared with age- and sex-matched reference populations (one-way t tests). A total of 553 longitudinal HRQL questionnaires were completed for 137 patients, truncated at 60 months. In the 2016 update, 85 responses were received from 103 survivors (mean follow-up period, 8.11 years). Patients' physical, role, and social function scores were impaired until 12 months postoperatively, after which the scores did not differ significantly from those of with reference populations. Similarly, fatigue, appetite loss, insomnia, and financial difficulties worsened significantly compared with reference populations in the first 12-months and then normalized. In contrast, impaired cognitive function (82.3 vs 88.5; P = 0.017), constipation (13.7 vs 7.3; P = 0.032), and diarrheal symptoms (15.1 vs 4.9; P = 0.0006) persisted through both periods. Global health scores did not differ significantly from those of the reference population. Beyond 12 months postoperatively, CRS-HIPEC for PMP is associated with a good quality of life except for some cognitive functional impairment and bowel disturbances.

"Development in Reverse?" A Longitudinal Analysis of Armed Conflict, Fragility and School Enrolment

ERIC Educational Resources Information Center

Shields, Robin; Paulson, Julia

2015-01-01

This paper presents a longitudinal analysis of cross-national data on armed conflict, state fragility, and enrolment in primary and secondary schooling. The study is motivated by questions raised in the 2012 "Human Security Report," which challenges the widely held assumption that conflict is necessarily detrimental to educational…

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…

A Longitudinal Analysis of Factors Related to Survival in Old Age.

ERIC Educational Resources Information Center

Shahtahmasebi, Said; And Others

1992-01-01

Used data from a longitudinal study of elderly which began in 1979 with 534 individuals in rural North Wales to study relationship between social circumstances and longevity. Multivariate analysis demonstrated there is no prima facie evidence that survival is affected by social networks or quality of life factors. However, socioeconomic factors…

Applying Longitudinal Mean and Covariance Structures (LMACS) Analysis to Assess Construct Stability Over Two Time Points: An Example Using Psychological Entitlement

ERIC Educational Resources Information Center

Bashkov, Bozhidar M.; Finney, Sara J.

2013-01-01

Traditional methods of assessing construct stability are reviewed and longitudinal mean and covariance structures (LMACS) analysis, a modern approach, is didactically illustrated using psychological entitlement data. Measurement invariance and latent variable stability results are interpreted, emphasizing substantive implications for educators and…

Marine dispersal determines the genetic population structure of migratory stream fauna of Puerto Rico: evidence for island-scale population recovery processes

Treesearch

Benjamin D. Cook; Sofie Bernays; Catherine M. Pringle; Jane M. Hughes

2009-01-01

Various components of island stream faunas, including caridean shrimps, fish, and gastropods, undertake obligate amphidromous migration, whereby larvae are released in upstream freshwater reaches, drift downstream to estuaries or marine waters, then migrate upstream as postlarvae to freshwater adult habitats. Longitudinal migration from estuaries to headwaters is well...

The Impact of Hearing Loss on Quality of Life in Older Adults

ERIC Educational Resources Information Center

Dalton, Dayna S.; Cruickshanks, Karen J.; Klein, Barbara E. K.; Klein, Ronald; Wiley, Terry L.; Nondahl, David M.

2003-01-01

Purpose: The authors investigate the impact of hearing loss on quality of life in a large population of older adults. Design and Methods: Data are from the 5-year follow-up Epidemiology of Hearing Loss Study, a population-based longitudinal study of age-related hearing impairment conducted in Beaver Dam, WI. Participants (N = 2,688) were 53-97…

Physical Function Decline and the Risk of Elder Self-Neglect in a Community-Dwelling Population

ERIC Educational Resources Information Center

Dong, XinQi; Simon, Melissa; Fulmer, Terry; de Leon, Carlos F. Mendes; Rajan, Bharat; Evans, Denis A.

2010-01-01

Purpose: This longitudinal study examines the association between physical function decline and the risk of elder self-neglect in a community-dwelling population. Design and Methods: Of the 5,570 participants in the Chicago Health Aging Project, 1,068 were reported to social services agency for suspected elder self-neglect from 1993 to 2005. The…

Can Routinely Collected Early Intervention Data for Deaf and Hard-of-Hearing Children Be Used for Outcome Monitoring? A Case Example from British Columbia, Canada

ERIC Educational Resources Information Center

Poon, Brenda T.; Simmons, Noreen R.

2016-01-01

Population-based outcome monitoring could provide useful information about factors that differentially influence the developmental trajectories of deaf or hard-of-hearing children. A strong basis for population-based outcome monitoring is a coordinated, longitudinal data collection, and management infrastructure that includes quality local…

Physical Aggression and Language Ability from 17 to 72 Months: Cross-Lagged Effects in a Population Sample

PubMed Central

Girard, Lisa-Christine; Pingault, Jean-Baptiste; Falissard, Bruno; Boivin, Michel; Dionne, Ginette; Tremblay, Richard E.

2014-01-01

Background Does poor language ability in early childhood increase the likelihood of physical aggression or is language ability delayed by frequent physical aggression? This study examined the longitudinal associations between physical aggression and language ability from toddlerhood to early childhood in a population sample while controlling for parenting behaviours, non-verbal intellectual functioning, and children’s sex. Methods Children enrolled in the Quebec Longitudinal Study of Child Development (QLSCD) (N = 2, 057) were assessed longitudinally from 17 to 72 months via parent reports and standardized assessments. Results The cross-lagged models revealed modest reciprocal associations between physical aggression and language performance from 17 to 41 months but not thereafter. Conclusions Significant associations between physical aggression and poor language ability are minimal and limited to the period when physical aggression and language performance are both substantially increasing. During that period parenting behaviours may play an important role in supporting language ability while reducing the frequency of physical aggression. Further studies are needed that utilize multiple assessments of physical aggression, assess multiple domains of language abilities, and that examine the potential mediating role of parenting behaviours between 12 and 48 months. PMID:25375971

Obesity and mobility disability in the older adult.

PubMed

Vincent, H K; Vincent, K R; Lamb, K M

2010-08-01

Mobility disability is becoming prevalent in the obese older population (> or = 60 years of age). We included a total of 13 cross-sectional and 15 longitudinal studies based on actual physical assessments of mobility in the obese older population in this review. We systematically examined existing evidence of which adiposity estimate best predicted mobility disability. Cross-sectional studies (82-4000 participants) showed poorer lower extremity mobility with increasing obesity severity in both men and women. All longitudinal studies (1-22 years) except for one, reported relationships between adiposity and declining mobility. While different physical tests made interpretation challenging, a consistent finding was that walking, stair climbing and chair rise ability were compromised with obesity, especially if the body mass index (BMI) exceeded 35 kg m(-2). More studies found that obese women were at an increased risk for mobility impairment than men. Existing evidence suggests that BMI and waist circumference are emerging as the more consistent predictors of the onset or worsening of mobility disability. Limited interventional evidence shows that weight loss is related with increased mobility and lower extremity function. Additional longitudinal studies are warranted that address overall body composition fat and muscle mass or change on future disability.

Quality differentials and reproductive health service utilisation determinants in India.

PubMed

Anand, Sandip; Sinha, R K

2010-01-01

This paper seeks to establish relationships between women's reproductive health service use, assessed longitudinally and by facility type, with service quality perceptions related to public or private health facilities. The study was mainly secondary and quantitative in nature. It included analysing data collected by the International Institute for Population Sciences (IIPS) and The Johns Hopkins University (JHU) as a follow-up study to the 1998-1999 National Family Health Survey (NFHS-2). The follow-up survey was carried out in Tamil Nadu, Maharashtra, Bihar and Jharkhand. In 2002-2003, these four states were selected to capture socio-economic and demographic variations. Analysis includes composite indices and logistic regression analysis. A scale was constructed to measure utilisation levels. Dimensions include: service proximity, doctor availability, waiting time, medicines, facility cleanliness, dignified treatment, privacy, service affordability and treatment effectiveness. Findings indicate that doctor availability, waiting time, cleanliness, privacy and affordability at private health facilities enhance the probability that a health facility will be used for any reproductive health purpose. At the combined states level, medicine availability and treatment effectiveness at public health facilities enhances service use. The major limitation is that the study includes only selected Indian states. The findings may enhance Indian service-quality policy. The paper's main contribution is that seemingly for the first time in India, healthcare service use has been measured longitudinally and then explained through service quality variables by comparing public and private health facilities.

A New Approach to Assess Lifetime Dietary Patterns Finds Lower Consumption of Animal Foods with Aging in a Longitudinal Analysis of a Health-Oriented Adventist Population

PubMed Central

Martins, Marcia C. T.; Jaceldo-Siegl, Karen; Fan, Jing; Mashchak, Andrew

2017-01-01

Life-course diet patterns may impact risk of disease, but little is known about dietary trends with aging. In a retrospective longitudinal analysis we estimated lifetime intake of animal products and adherence to vegetarian dietary patterns among 51,082 Adventist Health Study-2 (AHS-2) subjects using data from a reliable life-course dietary (meats, dairy, eggs) questionnaire. Results showed a marked tendency to consume fewer animal products (in total) in older years and to reduce consumption of meat, poultry and fish, but not eggs or dairy. Among the 29% of elderly subjects who during their lifetime kept the same dietary pattern (LTS) were: LTS-vegans (1.1%), LTS-lacto-ovo vegetarians (31.2%), LTS-pesco vegetarians (0.49%), LTS-semi vegetarians (3.7%), and LTS-non-vegetarians (63.5%). Among the 71% of switchers were “Converters” (59.7%) who moved towards and “Reverters” (9.1%) who moved away from vegetarian diets, and Multiverters (31.2%), who had moved in both directions. LTS-non-vegetarians, and also reverters, were more overweight and showed a less healthy lifestyle than others. We conclude that the dietary patterns are dynamic with strong trends to reduce animal foods and to adopt more vegetarian patterns with aging. The disease experience of subjects with different lifetime dietary patterns can be compared. PMID:29027960

Impact of multidimensional poverty on the self-efficacy of older people: Results from an Australian longitudinal study.

PubMed

Callander, Emily J; Schofield, Deborah J

2017-02-01

Self-efficacy has numerous benefits for active and healthy aging, including giving the people the ability to make positive changes to their living standards and lifestyles. The present study aims to determine whether falling into multidimensional poverty lowers self-efficacy. Longitudinal analysis of waves 7-11 (2007-2011) of the nationally representative Household, Income and Labor Dynamics in Australia survey using linear regression models. The analysis focused on the Australian population aged 65 years and older. The Freedom Poverty Measure was used to identify those in multidimensional poverty. Those who fell into multidimensional poverty for 3 or 4 years between 2007 and 2011 had their self-efficacy scores decline by an average of 27 points (SD 21.2). Those who fell into poverty had significantly lower self-efficacy scores in 2011 - up to 57% lower (-66.6%, -45.7% P < 0.0001) after being in multidimensional poverty for 3 or 4 years between 2007 and 2011 than those who were never in poverty. Falling into multidimensional poverty lowers the self-efficacy scores of older people. In order to improve the chances of older people making long-term changes to improve their living standards, feelings of self-efficacy should first be assessed and improved. Geriatr Gerontol Int 2017; 17: 308-314. © 2015 Japan Geriatrics Society.

Longitudinal data for interdisciplinary ageing research. Design of the Linnaeus Database.

PubMed

Malmberg, Gunnar; Nilsson, Lars-Göran; Weinehall, Lars

2010-11-01

To allow for interdisciplinary research on the relations between socioeconomic conditions and health in the ageing population, a new anonymized longitudinal database - the Linnaeus Database - has been developed at the Centre for Population Studies at Umeå University. This paper presents the database and its research potential. Using the Swedish personal numbers the researchers have, in collaboration with Statistics Sweden and the National Board for Health and Welfare, linked individual records from Swedish register data on death causes, hospitalization and various socioeconomic conditions with two databases - Betula and VIP (Västerbottens Intervention Programme) - previously developed by the researchers at Umeå University. Whereas Betula includes rich information about e.g. cognitive functions, VIP contains information about e.g. lifestyle and health indicators. The Linnaeus Database includes annually updated socioeconomic information from Statistics Sweden registers for all registered residents of Sweden for the period 1990 to 2006, in total 12,066,478. The information from the Betula includes 4,500 participants from the city of Umeå and VIP includes data for almost 90,000 participants. Both datasets include cross-sectional as well as longitudinal information. Due to the coverage and rich information, the Linnaeus Database allows for a variety of longitudinal studies on the relations between, for instance, socioeconomic conditions, health, lifestyle, cognition, family networks, migration and working conditions in ageing cohorts. By joining various datasets developed in different disciplinary traditions new possibilities for interdisciplinary research on ageing emerge.

Patient-Related Benefits for Adults with Cochlear Implantation: A Multicultural Longitudinal Observational Study.

PubMed

Lenarz, Thomas; Muller, Lida; Czerniejewska-Wolska, Hanna; Vallés Varela, Hector; Orús Dotú, César; Durko, Marcin; Huarte Irujo, Alicia; Piszczatowski, Bartosz; Zadrożniak, Marek; Irwin, Colin; Graham, Petra L; Wyss, Josie

2017-01-01

To assess subjectively perceived, real-world benefits longitudinally for unilateral cochlear implant (CI) recipients in a multinational population treated routinely. To identify possible predictors of self-reported benefits. This was a prospective, multicenter, repeated-measures study. Self-assessment of performance at preimplantation and postimplantation at 1, 2, and 3 years using standardized, validated, local language versions of the Speech, Spatial, and Qualities of Hearing Scale (SSQ), and the Health Utilities Index Mark 3 (HUI3) was performed. Outcomes were analyzed using a longitudinal mixed-effects model incorporating country effect. Patient demographics were explored for associations with change over time. Two hundred ninety-one routinely treated, unilateral CI recipients, aged 13-81 years, from 9 clinics across 4 countries. Highly significant improvements were observed for all outcome measures (p < 0.0001). Postimplantation, mean outcome scores remained stable beyond 1 year, with notable individual variability. A significant association for one or more outcomes with preimplantation contralateral hearing aid use, telephone use, age at implantation, implantation side, preimplantation comorbidities, dizziness, and tinnitus was observed (p < 0.004). Longitudinal benefits of CI treatment can be measured using clinically standardized self-assessment tools to provide a holistic view of patient-related benefits in routine clinical practice for aggregated data from multinational populations. Self-reported outcomes can provide medical-based evidence regarding CI treatment to support decision-making by health service providers. © 2017 The Author(s) Published by S. Karger AG, Basel.

Construction strength analysis of landing craft tank conversion to passenger ship using finite element method

NASA Astrophysics Data System (ADS)

Nurul Misbah, Mohammad; Setyawan, Dony; Murti Dananjaya, Wisnu

2018-03-01

This research aims to determine the longitudinal strength of passenger ship which was converted from Landing Craft Tank with 54 m of length as stated by BKI (Biro Klasifikasi Indonesia / Indonesian Classification Bureau). Verification of strength value is done to 4 (four) loading conditions which are (1) empty load condition during sagging wave, (2) empty load condition during hogging wave, (3) full load condition during sagging wave and (4) full load condition during hogging wave. Analysis is done using Finite Element Analysis (FEA) software by modeling the entire part of passenger ship and its loading condition. The back and upfront part of ship centerline were used as the boundary condition. From that analysis it can be concluded that the maximum stress for load condition (1) is 72,393 MPa, 74,792 MPa for load condition (2), 129,92 MPa for load condition (3), and 132,4 MPa for load condition (4). Longitudinal strength of passenger ship fulfilled the criteria of empty load condition having smaller stress value than allowable stress which is 90 MPa, and during full load condition with smaller stress value than allowable stress which is 150 MPa. Analysis on longitudinal strength comparison with entire ship plate thickness variation of ± 2 mm from initial plate was also done during this research. From this research it can be concluded that plate thickness reduction causes the value of longitudinal strength to decrease, while plate thickness addition causes the value of longitudinal strength to increase.

Caffeine Consumption and General Health in Secondary School Children: A Cross-sectional and Longitudinal Analysis

PubMed Central

Richards, Gareth; Smith, Andrew P.

2016-01-01

Although caffeine is sometimes associated with beneficial effects in adults, the substance may be dangerous if intake is too high. This concern is particularly relevant in regards to children and adolescents, as consumption of energy drinks may be particularly high in such populations. For this reason, the current study examined data from the Cornish Academies Project to determine whether caffeine intake in secondary school children was related to responses to a single-item measure of general health. Two cross-sections of data were available: questionnaires were completed by 2030 at baseline, by 2307 at 6-month follow-up, and by 1660 at both time-points. Relationships were, therefore, explored both cross-sectionally and longitudinally. High caffeine consumption (i.e., 1000 mg/week) was associated with low general health in both cross-sections of data, and analyses of individual caffeine sources suggested that the effects related specifically to cola and energy drinks. However, after controlling for additional aspects of diet, demography, and lifestyle, total weekly intake only remained significantly associated with general health at the latter time-point. Further to this, null findings from cross-lag and change-score analyses suggest that caffeine and general health were unlikely to be causally linked in this sample. However, due to methodological limitations, such as the two cross-sections of data being collected only 6 months apart, it is suggested that further longitudinal and intervention studies are required in order for firm conclusions to be drawn. PMID:27965962

Differential rate in decline in ovarian reserve markers in women with polycystic ovary syndrome compared with control subjects: results of a longitudinal study.

PubMed

Ahmad, Asima K; Kao, Chia-Ning; Quinn, Molly; Lenhart, Nikolaus; Rosen, Mitchell; Cedars, Marcelle I; Huddleston, Heather

2018-03-01

To estimate rates of ovarian aging in polycystic ovary syndrome (PCOS) subjects versus a community control population. Longitudinal. Tertiary academic center. PCOS subjects diagnosed according to the 2004 Rotterdam criteria were systematically enrolled in a PCOS cohort study. The comparison control subjects were from the Ovarian Aging study, a prospective longitudinal study of ovarian aging in healthy women with regular menstrual cycles. Clinical data collection over two study visits. Antral follicle count (AFC), ovarian volume (OV), and antimüllerian hormone level (AMH). PCOS subjects were found to have higher baseline values for all ovarian reserve markers compared with control subjects. Univariate models indicated that, compared with control subjects, PCOS patients experienced significantly faster rates of decline for both AFC and AMH. Change in OV did not differ significantly. To account for potential confounder effects, multiple analysis of covariance models were evaluated for the best fit, considering age, body mass index, and baseline ovarian reserve markers. Adjusted models demonstrated that PCOS patients do not experience a significant difference in AFC decline compared with control subjects, but they do experience a faster rate of decline in AMH (P<.01) and slower rate of decline in OV (P<.01). Ovarian aging in PCOS is characterized by a more rapid decline in AMH and a slower decline in OV compared with control subjects. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Longitudinal associations between parenting style and adolescent disordered eating behaviors.

PubMed

Zubatsky, Max; Berge, Jerica; Neumark-Sztainer, Dianne

2015-06-01

The main purpose of this study was to identify the longitudinal association between specific parenting styles (authoritarian, authoritative, permissive, and neglectful) and adolescent disordered eating behaviors. The current study uses longitudinal data from a 5-year study to examine the associations between parenting style and disordered eating behaviors among adolescents. Data from adolescents (n = 2516) participating in Project EAT (Eating Among Teens), a population-based study from 31 Minnesota schools, were used in the analysis. Time 1 data were collected using in-class assessments of adolescents from Minneapolis/St. Paul schools, and Time 2 data were collected using mailed surveys 5 years later. General Linear Models were used to predict adolescent-reported disordered eating behaviors at Time 2 from adolescent-reported parenting style at Time 1. Adolescent boys and girls who had authoritarian mothers at Time 1 had a higher probability of extreme weight control behaviors 5 years later compared to adolescents with authoritative, permissive, or neglectful mothers. Adolescent girls with authoritarian mothers at Time 1 had a higher probability of engaging in binge-eating behaviors at Time 2 compared to adolescent girls with authoritative or permissive mothers. There were no significant associations between paternal parenting style and adolescent disordered eating behaviors. Although authoritarian parenting style served as a possible risk factor for disordered eating behaviors in adolescents, the findings were not conclusive. Future studies should investigate further the association between parenting style and weight control behaviors in adolescents.

Event History Data and Survey Recall. An Analysis of the Longitudinal Survey of Youth 1979 Recall Experiment.

ERIC Educational Resources Information Center

Pierret, Charles R.

2001-01-01

To test the effect of less-frequent interviews on data quality in longitudinal surveys, event history data from the National Longitudinal Survey of Youth 1979 regarding welfare and employment were analyzed. Due to the longer recall period, respondents failed to report short spells of welfare, employment, and unemployment. (SK)

Using Longitudinal Assessment Data to Improve Retention and Student Experiences

ERIC Educational Resources Information Center

Trosset, Carol; Weisler, Steven

2010-01-01

The Wabash National Study of Liberal Arts Education presents a longitudinal analysis of how students change on a number of scales that purport to measure many of the outcomes of liberal learning over the span of a college education. The Wabash Study is designed to collect information longitudinally from students at the beginning and end of their…

Application of the Levenshtein Distance Metric for the Construction of Longitudinal Data Files

ERIC Educational Resources Information Center

Doran, Harold C.; van Wamelen, Paul B.

2010-01-01

The analysis of longitudinal data in education is becoming more prevalent given the nature of testing systems constructed for No Child Left Behind Act (NCLB). However, constructing the longitudinal data files remains a significant challenge. Students move into new schools, but in many cases the unique identifiers (ID) that should remain constant…

Research Assistants Caught in Limbo: Considering Their Role in Quantitative, Longitudinal Research with Vulnerable Populations.

PubMed

Zerger, Suzanne; Pridham, Katherine Francombe; Plenert, Erin; Newberry, Caitlin; Whisler, Adam; Fernando, Indira; Ahmed, Naveed

2015-11-01

Research assistants (RAs) play a variety of roles that are critical in making research happen and in determining its quality and effectiveness. Yet their locus of power in the production of knowledge stands in sharp contrast to their relative powerlessness in the hierarchical research organization. This article explores the experiences of RAs engaged in a randomized controlled longitudinal field trial of a Housing First intervention for individuals experiencing homelessness and mental illness in Toronto. They encountered several unexpected effects of navigating the power ascribed to them by both study participants and community service providers. This study underscores the importance of acknowledging that RAs are the face of the research study in the field, and of better understanding implications associated with that fact, especially when marginalized populations and their providers are involved.

Diffuse idiopathic skeletal hyperostosis from Roman Hungary.

PubMed

Hlavenková, Lucia; Gábor, Olivér; Benus, Radoslav; Smrcka, Václav; Jambor, Jaroslav; Hajdu, Tamás

2013-01-01

This paper deals with cases of diffuse idiopathic skeletal hyperostosis (DISH) found at the Late Roman Age necropolis in Pécs, Hungary (4th century AD). The skeletal remains of two male individuals, aged between 60-70 years and 45-55 years, displayed right-sided ossification of the anterior longitudinal ligament with extra-spinal manifestations typical in DISH cases. It is presumed that both male individuals were middle-class citizens. Their social status was supplemented with trace element analysis in order to reconstruct the dietary habits of the urban population. Concentrations of Sr and Zn indicated a predominantly vegetal diet. Potential DISH risk factors and associations were subsequently discussed and compared with our findings.

Longitudinal bunch monitoring at the Fermilab Tevatron and Main Injector synchrotrons

DOE PAGES

Thurman-Keup, R.; Bhat, C.; Blokland, W.; ...

2011-10-17

The measurement of the longitudinal behavior of the accelerated particle beams at Fermilab is crucial to the optimization and control of the beam and the maximizing of the integrated luminosity for the particle physics experiments. Longitudinal measurements in the Tevatron and Main Injector synchrotrons are based on the analysis of signals from resistive wall current monitors. This study describes the signal processing performed by a 2 GHz-bandwidth oscilloscope together with a computer running a LabVIEW program which calculates the longitudinal beam parameters.

A longitudinal evaluation of the Center for Epidemiologic Studies-Depression scale (CES-D) in a Rheumatoid Arthritis Population using Rasch Analysis

PubMed Central

Covic, Tanya; Pallant, Julie F; Conaghan, Philip G; Tennant, Alan

2007-01-01

Background The aim of this study was to test the internal validity of the total Center for Epidemiologic Studies-Depression (CES-D) scale using Rasch analysis in a rheumatoid arthritis (RA) population. Methods CES-D was administered to 157 patients with RA over three time points within a 12 month period. Rasch analysis was applied using RUMM2020 software to assess the overall fit of the model, the response scale used, individual item fit, differential item functioning (DIF) and person separation. Results Pooled data across three time points was shown to fit the Rasch model with removal of seven items from the original 20-item CES-D scale. It was necessary to rescore the response format from four to three categories in order to improve the scale's fit. Two items demonstrated some DIF for age and gender but were retained within the 13-item CES-D scale. A new cut point for depression score of 9 was found to correspond to the original cut point score of 16 in the full CES-D scale. Conclusion This Rasch analysis of the CES-D in a longstanding RA cohort resulted in the construction of a modified 13-item scale with good internal validity. Further validation of the modified scale is recommended particularly in relation to the new cut point for depression. PMID:17629902

Multivariate longitudinal data analysis with censored and intermittent missing responses.

PubMed

Lin, Tsung-I; Lachos, Victor H; Wang, Wan-Lun

2018-05-08

The multivariate linear mixed model (MLMM) has emerged as an important analytical tool for longitudinal data with multiple outcomes. However, the analysis of multivariate longitudinal data could be complicated by the presence of censored measurements because of a detection limit of the assay in combination with unavoidable missing values arising when subjects miss some of their scheduled visits intermittently. This paper presents a generalization of the MLMM approach, called the MLMM-CM, for a joint analysis of the multivariate longitudinal data with censored and intermittent missing responses. A computationally feasible expectation maximization-based procedure is developed to carry out maximum likelihood estimation within the MLMM-CM framework. Moreover, the asymptotic standard errors of fixed effects are explicitly obtained via the information-based method. We illustrate our methodology by using simulated data and a case study from an AIDS clinical trial. Experimental results reveal that the proposed method is able to provide more satisfactory performance as compared with the traditional MLMM approach. Copyright © 2018 John Wiley & Sons, Ltd.

Joint principal trend analysis for longitudinal high-dimensional data.

PubMed

Zhang, Yuping; Ouyang, Zhengqing

2018-06-01

We consider a research scenario motivated by integrating multiple sources of information for better knowledge discovery in diverse dynamic biological processes. Given two longitudinal high-dimensional datasets for a group of subjects, we want to extract shared latent trends and identify relevant features. To solve this problem, we present a new statistical method named as joint principal trend analysis (JPTA). We demonstrate the utility of JPTA through simulations and applications to gene expression data of the mammalian cell cycle and longitudinal transcriptional profiling data in response to influenza viral infections. © 2017, The International Biometric Society.

Association analysis of whole genome sequencing data accounting for longitudinal and family designs.

PubMed

Hu, Yijuan; Hui, Qin; Sun, Yan V

2014-01-01

Using the whole genome sequencing data and the simulated longitudinal phenotypes for 849 pedigree-based individuals from Genetic Analysis Workshop 18, we investigated various approaches to detecting the association of rare and common variants with blood pressure traits. We compared three strategies for longitudinal data: (a) using the baseline measurement only, (b) using the average from multiple visits, and (c) using all individual measurements. We also compared the power of using all of the pedigree-based data and the unrelated subset. The analyses were performed without knowledge of the underlying simulating model.

What Can Science Do for Me? Engaging Urban Teens in the Chandra Astrophysics Institute

NASA Astrophysics Data System (ADS)

Hartman, M.; Porro, I.; Baganoff, F.

2008-06-01

We present three years of longitudinal data showing how we can engage underrepresented high-school youth in out-of-school time research science. Over three years our participant population has evolved to be more reflective of the Boston student population as a result of changes in our recruitment strategy. In addition, changes in 4 major program areas helped all participant populations move toward our intended outcome of better understanding of the process of research science.

Construction of a web-based questionnaire for longitudinal investigation of work exposure, musculoskeletal pain and performance impairments in high-performance marine craft populations

PubMed Central

de Alwis, Manudul Pahansen; Äng, Björn Olov; Garme, Karl

2017-01-01

Objective High-performance marine craft personnel (HPMCP) are regularly exposed to vibration and repeated shock (VRS) levels exceeding maximum limitations stated by international legislation. Whereas such exposure reportedly is detrimental to health and performance, the epidemiological data necessary to link these adverse effects causally to VRS are not available in the scientific literature, and no suitable tools for acquiring such data exist. This study therefore constructed a questionnaire for longitudinal investigations in HPMCP. Methods A consensus panel defined content domains, identified relevant items and outlined a questionnaire. The relevance and simplicity of the questionnaire’s content were then systematically assessed by expert raters in three consecutive stages, each followed by revisions. An item-level content validity index (I-CVI) was computed as the proportion of experts rating an item as relevant and simple, and a scale-level content validity index (S-CVI/Ave) as the average I-CVI across items. The thresholds for acceptable content validity were 0.78 and 0.90, respectively. Finally, a dynamic web version of the questionnaire was constructed and pilot tested over a 1-month period during a marine exercise in a study population sample of eight subjects, while accelerometers simultaneously quantified VRS exposure. Results Content domains were defined as work exposure, musculoskeletal pain and human performance, and items were selected to reflect these constructs. Ratings from nine experts yielded S-CVI/Ave of 0.97 and 1.00 for relevance and simplicity, respectively, and the pilot test suggested that responses were sensitive to change in acceleration and that the questionnaire, following some adjustments, was feasible for its intended purpose. Conclusions A dynamic web-based questionnaire for longitudinal survey of key variables in HPMCP was constructed. Expert ratings supported that the questionnaire content is relevant, simple and sufficiently comprehensive, and the pilot test suggested that the questionnaire is feasible for longitudinal measurements in the study population. PMID:28729320

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.

Trends in traumatic brain injury mortality in China, 2006-2013: A population-based longitudinal study.

PubMed

Cheng, Peixia; Yin, Peng; Ning, Peishan; Wang, Lijun; Cheng, Xunjie; Liu, Yunning; Schwebel, David C; Liu, Jiangmei; Qi, Jinlei; Hu, Guoqing; Zhou, Maigeng

2017-07-01

Traumatic brain injury (TBI) is a significant global public health problem, but has received minimal attention from researchers and policy-makers in low- and middle-income countries (LMICs). Epidemiological evidence of TBI morbidity and mortality is absent at the national level for most LMICs, including China. Using data from China's Disease Surveillance Points (DSPs) system, we conducted a population-based longitudinal analysis to examine TBI mortality, and mortality differences by sex, age group, location (urban/rural), and external cause of injury, from 1 January 2006 to 31 December 2013 in China. Mortality data came from the national DSPs system of China, which has coded deaths using the International Classification of Diseases-10th Revision (ICD-10) since 2004. Crude and age-standardized mortality with 95% CIs were estimated using the census population in 2010 as a reference population. The Cochran-Armitage trend test was used to examine the significance of trends in mortality from 2006 to 2013. Negative binomial models were used to examine the associations of TBI mortality with location, sex, and age group. Subgroup analysis was performed by external cause of TBI. We found the following: (1) Age-adjusted TBI mortality increased from 13.23 per 100,000 population in 2006 to 17.06 per 100,000 population in 2008 and then began to fall slightly. In 2013, age-adjusted TBI mortality was 12.99 per 100,000 population (SE = 0.13). (2) Compared to females and urban residents, males and rural residents had higher TBI mortality risk, with adjusted mortality rate ratios of 2.57 and 1.71, respectively. TBI mortality increased substantially with older age. (3) Motor vehicle crashes and falls were the 2 leading causes of TBI mortality between 2006 and 2013. TBI deaths from motor vehicle crashes in children aged 0-14 years and adults aged 65 years and older were most often in pedestrians, and motorcyclists were the first or second leading category of road user for the other age groups. (4) TBI mortality attributed to motor vehicle crashes increased for pedestrians and motorcyclists in all 7 age groups from 2006 to 2013. Our analysis was limited by the availability and quality of data in the DSPs dataset, including lack of injury-related socio-economic factors, policy factors, and individual and behavioral factors. The dataset also may be incomplete in TBI death recording or contain misclassification of mortality data. TBI constitutes a serious public health threat in China. Further studies should explore the reasons for the particularly high risk of TBI mortality among particular populations, as well as the reasons for recent increases in certain subgroups, and should develop solutions to address these challenges. Interventions proven to work in other cultures should be introduced and implemented nationwide. Examples of these in the domain of motor vehicle crashes include policy change and enforcement of laws concerning helmet use for motorcyclists and bicyclists, car seat and booster seat use for child motor vehicle passengers, speed limit and drunk driving laws, and alcohol ignition interlock use. Examples to prevent falls, especially among elderly individuals, include exercise programs, home modification to reduce fall risk, and multifaceted interventions to prevent falls in all age groups.

The State of PR Graduate Curriculum as We Know It: A Longitudinal Analysis

ERIC Educational Resources Information Center

Briones, Rowena L.; Toth, Elizabeth L.

2013-01-01

This longitudinal content analysis study uses the Commission on Public Relations Education's 2006 report as a benchmark to determine whether master's education in public relations has evolved over the past decade. Findings show a lack of uniformity across the 75 programs studied. In addition, there is a lack of adherence to the Commission on…

Friendship Quality and School Achievement: A Longitudinal Analysis during Primary School

ERIC Educational Resources Information Center

Zucchetti, Giulia; Candela, Filippo; Sacconi, Beatrice; Rabaglietti, Emanuela

2015-01-01

This study examined the longitudinal relationship between friendship quality (positive and negative) and school achievement among 228 school-age children (51% girls, M = 8.09, SD = 0.41). A three-wave cross-lagged analysis was used to determine the direction of influence between these domains across school years. Findings revealed that: (a) school…

Social Capital, Self-Esteem, and Use of Online Social Network Sites: A Longitudinal Analysis

ERIC Educational Resources Information Center

Steinfield, Charles; Ellison, Nicole B.; Lampe, Cliff

2008-01-01

A longitudinal analysis of panel data from users of a popular online social network site, Facebook, investigated the relationship between intensity of Facebook use, measures of psychological well-being, and bridging social capital. Two surveys conducted a year apart at a large U.S. university, complemented with in-depth interviews with 18 Facebook…

Accolades and Recommendations: A Longitudinal Analysis of Monitoring Reports for Two Charter Schools Serving Native American Students

ERIC Educational Resources Information Center

Anderson, Derek L.; Holder, K. C.

2012-01-01

This longitudinal case study examines 10 years' worth of annual monitoring reports for two rural Native American Charter Schools. Using data from multiple sources including interviews, site visits, and document analyses, the authors used provisional coding and constant comparison analysis to categorize the accolades and recommendations embedded in…

Examining the Influence of Campus Climate on Students' Time to Degree: A Multilevel Discrete-Time Survival Analysis

ERIC Educational Resources Information Center

Zhou, Ji; Castellanos, Michelle

2013-01-01

Utilizing longitudinal data of 3477 students from 28 institutions, we examine the effects of structural diversity and quality of interracial relation on students' persistence towards graduation within six years. We utilize multilevel discrete-time survival analysis to account for the longitudinal persistence patterns as well as the nested…

Time-to-Event Analysis of Individual Variables Associated with Nursing Students' Academic Failure: A Longitudinal Study

ERIC Educational Resources Information Center

Dante, Angelo; Fabris, Stefano; Palese, Alvisa

2013-01-01

Empirical studies and conceptual frameworks presented in the extant literature offer a static imagining of academic failure. Time-to-event analysis, which captures the dynamism of individual factors, as when they determine the failure to properly tailor timely strategies, impose longitudinal studies which are still lacking within the field. The…

Longitudinal assessment of treatment effects on pulmonary ventilation using 1H/3He MRI multivariate templates

NASA Astrophysics Data System (ADS)

Tustison, Nicholas J.; Contrella, Benjamin; Altes, Talissa A.; Avants, Brian B.; de Lange, Eduard E.; Mugler, John P.

2013-03-01

The utitlity of pulmonary functional imaging techniques, such as hyperpolarized 3He MRI, has encouraged their inclusion in research studies for longitudinal assessment of disease progression and the study of treatment effects. We present methodology for performing voxelwise statistical analysis of ventilation maps derived from hyper­ polarized 3He MRI which incorporates multivariate template construction using simultaneous acquisition of IH and 3He images. Additional processing steps include intensity normalization, bias correction, 4-D longitudinal segmentation, and generation of expected ventilation maps prior to voxelwise regression analysis. Analysis is demonstrated on a cohort of eight individuals with diagnosed cystic fibrosis (CF) undergoing treatment imaged five times every two weeks with a prescribed treatment schedule.

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.

Determinant of Road Traffic Crash Fatalities in Iran: A Longitudinal Econometric Analysis.

PubMed

Rezaei, Satar; Bagheri Lankarani, Kamran; Karami Matin, Behzad; Bazyar, Mohammad; Hamzeh, Behrooz; Najafi, Farid

2015-01-01

Injuries and deaths from road traffic crashes are one of the main public health problems throughout the world. This study aimed to identify determinants of fatality traffic accident in Iran for the twenty-span year from 1991 to 2011. A time series analysis (1991-2011) was used to examine the effects of some of the key explanatory factors (GDP per capita, number of doctors per 10,000 populations, degree of urbanization, unemployment rate and motorization rate) on deaths from road traffic in Iran. In order to examine long- and short-run effects of variables, we employed autoregressive distributed lag (ARDL) approach and error correction method (ECM). The data for the study was obtained from the Central Bank of Iran (CBI), Iranian Statistical Center (ISC) and Legal medical organizations (LMO). GDP per capita, doctor per 10,000 populations, degree of urbanization and motorization rate had a significant impact on fatality from road traffic in Iran. We did not observe any short- and long-term effects of the unemployment rate on fatality from road traffic. GDP per capita, doctor per 10,000 populations, degree of urbanization and motorization rate were identified as main determinant of fatality from road traffic accidents in Iran. We hope the results of the current study enable health policy-makers to understand better the factors affecting deaths from road traffic accidents in the country.

Moving forward: using the experience of the CDCs' Colorectal Cancer Screening Demonstration Program to guide future colorectal cancer programming efforts.

PubMed

Seeff, Laura C; DeGroff, Amy; Joseph, Djenaba A; Royalty, Janet; Tangka, Florence K L; Nadel, Marion R; Plescia, Marcus

2013-08-01

The Centers for Disease Control and Prevention (CDC) established and supported a 4-year Colorectal Cancer Screening Demonstration Program (CRCSDP) from 2005 to 2009 for low-income, under- or uninsured men and women aged 50-64 at 5 sites in the United States. A multiple methods evaluation was conducted including 1) a longitudinal, comparative case study of program implementation, 2) the collection and analysis of client-level screening and diagnostic services outcome data, and 3) the collection and analysis of program- and patient-level cost data. Several themes emerged from the results reported in the series of articles in this Supplement. These included the benefit of building on an existing infrastructure, strengths and weakness of both the 2 most frequently used screening tests (colonoscopy and fecal occult blood tests), variability in costs of maintaining this screening program, and the importance of measuring the quality of screening tests. Population-level evaluation questions could not be answered because of the small size of the participating population and the limited time frame of the evaluation. The comprehensive evaluation of the program determined overall feasibility of this effort. Critical lessons learned through the implementation and evaluation of the CDC's CRCSDP led to the development of a larger population-based program, the CDC's Colorectal Cancer Control Program (CRCCP). © 2013 American Cancer Society.

Using a Large Scale Computational Model to Study the Effect of Longitudinal and Radial Electrical Coupling in the Cochlea

NASA Astrophysics Data System (ADS)

Mistrík, Pavel; Ashmore, Jonathan

2009-02-01

We describe a large scale computational model of electrical current flow in the cochlea which is constructed by a flexible Modified Nodal Analysis algorithm to incorporate electrical components representing hair cells and the intercellular radial and longitudinal current flow. The model is used as a laboratory to study the effects of changing longitudinal gap junctional coupling, and shows the way in which cochlear microphonic spreads and tuning is affected. The process for incorporating mechanical longitudinal coupling and feedback is described. We find a difference in tuning and attenuation depending on whether longitudinal or radial couplings are altered.

Coping Among Victims of Relationship Abuse: A Longitudinal Examination

PubMed Central

Taft, Casey T.; Resick, Patricia A.; Panuzio, Jillian; Vogt, Dawne S.; Mechanic, Mindy B.

2010-01-01

This longitudinal study examined the associations between relationship abuse, coping variables, and mental health outcomes among a sample of battered women obtained from shelter and nonresidential community agencies (N = 61). Sexual aggression was a stronger predictor of poorer mental health than was physical assault. Engagement coping strategies were generally predictive of positive mental health, and disengagement coping strategies were generally predictive of poorer mental health. Results highlight the complexity of the associations between different forms of relationship abuse, coping strategies, and mental health among this population. PMID:17691549

The clinical importance of white matter hyperintensities on brain magnetic resonance imaging: systematic review and meta-analysis.

PubMed

Debette, Stéphanie; Markus, H S

2010-07-26

To review the evidence for an association of white matter hyperintensities with risk of stroke, cognitive decline, dementia, and death. Systematic review and meta-analysis. PubMed from 1966 to 23 November 2009. Prospective longitudinal studies that used magnetic resonance imaging and assessed the impact of white matter hyperintensities on risk of incident stroke, cognitive decline, dementia, and death, and, for the meta-analysis, studies that provided risk estimates for a categorical measure of white matter hyperintensities, assessing the impact of these lesions on risk of stroke, dementia, and death. Population studied, duration of follow-up, method used to measure white matter hyperintensities, definition of the outcome, and measure of the association of white matter hyperintensities with the outcome. 46 longitudinal studies evaluated the association of white matter hyperintensities with risk of stroke (n=12), cognitive decline (n=19), dementia (n=17), and death (n=10). 22 studies could be included in a meta-analysis (nine of stroke, nine of dementia, eight of death). White matter hyperintensities were associated with an increased risk of stroke (hazard ratio 3.3, 95% confidence interval 2.6 to 4.4), dementia (1.9, 1.3 to 2.8), and death (2.0, 1.6 to 2.7). An association of white matter hyperintensities with a faster decline in global cognitive performance, executive function, and processing speed was also suggested. White matter hyperintensities predict an increased risk of stroke, dementia, and death. Therefore white matter hyperintensities indicate an increased risk of cerebrovascular events when identified as part of diagnostic investigations, and support their use as an intermediate marker in a research setting. Their discovery should prompt detailed screening for risk factors of stroke and dementia.

Typical Pubertal Timing in an Australian Population of Girls and Boys with Autism Spectrum Disorder

ERIC Educational Resources Information Center

May, Tamara; Pang, Ken C.; O'Connell, Michele A.; Williams, Katrina

2017-01-01

Secondary data analyses from the Longitudinal Study of Australian Children Kindergarten cohort were performed to understand any alterations in pubertal timing in Autism Spectrum Disorder (ASD) in a population sample. Timing of parent-reported pubertal events (ages 8-9, 10-11, 12-13 years), and self-report (14-15 years; N = 3454 no ASD, N = 94 with…

"We're Not Going to Suffer Like This in the Mud": Educational Aspirations, Social Mobility and Independent Child Migration among Populations Living in Poverty

ERIC Educational Resources Information Center

Boyden, Jo

2013-01-01

This article examines the association between formal education, social mobility and independent child migration in Ethiopia, India (Andhra Pradesh), Peru and Vietnam and draws on data from Young Lives, a longitudinal study of childhood poverty and schooling. It argues that among resource-poor populations, child migration sustains kin relations…

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.

Participatory design of ehealth solutions for women from vulnerable populations with perinatal depression.

PubMed

Gordon, Mara; Henderson, Rebecca; Holmes, John H; Wolters, Maria K; Bennett, Ian M

2016-01-01

Cultural and health service obstacles affect the quality of pregnancy care that women from vulnerable populations receive. Using a participatory design approach, the Stress in Pregnancy: Improving Results with Interactive Technology group developed specifications for a suite of eHealth applications to improve the quality of perinatal mental health care. We established a longitudinal participatory design group consisting of low-income women with a history of antenatal depression, their prenatal providers, mental health specialists, an app developer, and researchers. The group met 20 times over 24 months. Applications were designed using rapid prototyping. Meetings were documented using field notes. The group achieved high levels of continuity and engagement. Three apps were developed by the group: an app to support high-risk women after discharge from hospital, a screening tool for depression, and a patient decision aid for supporting treatment choice. Longitudinal participatory design groups are a promising, highly feasible approach to developing technology for underserved populations. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Vaccination coverage among children in Germany estimated by analysis of health insurance claims data

PubMed Central

Rieck, Thorsten; Feig, Marcel; Eckmanns, Tim; Benzler, Justus; Siedler, Anette; Wichmann, Ole

2014-01-01

In Germany, the national routine childhood immunization schedule comprises 12 vaccinations. Primary immunizations should be completed by 24 mo of age. However, nationwide monitoring of vaccination coverage (VC) is performed only at school entry. We utilized health insurance claims data covering ~85% of the total population with the objectives to (1) assess VC of all recommended childhood vaccinations in birth-cohorts 2004–2009, (2) analyze cross-sectional (at 24 and 36 mo) and longitudinal trends, and (3) validate the method internally and externally. Counting vaccine doses in a retrospective cohort fashion, we assembled individual vaccination histories and summarized VC to nationwide figures. For most long-established vaccinations, VC at 24 mo was at moderate levels (~73–80%) and increased slightly across birth-cohorts. One dose measles VC was high (94%), but low (69%) for the second dose. VC with a full course of recently introduced varicella, pneumococcal, and meningococcal C vaccines increased across birth-cohorts from below 10% above 60%, 70%, and 80%, respectively. At 36 mo, VC had increased further by up to 15 percentage points depending on vaccination. Longitudinal analysis suggested a continued VC increase until school entry. Validation of VC figures with primary data showed an overall good agreement. In conclusion, analysis of health insurance claims data allows for the estimation of VC among children in Germany considering completeness and timeliness of vaccination series. This approach provides valid nationwide VC figures for all currently recommended pediatric vaccinations and fills the information gap between early infancy and late assessment at school entry. PMID:24192604

Dietary Variety and Decline in Lean Mass and Physical Performance in Community-Dwelling Older Japanese: A 4-year Follow-Up Study.

PubMed

Yokoyama, Y; Nishi, M; Murayama, H; Amano, H; Taniguchi, Y; Nofuji, Y; Narita, M; Matsuo, E; Seino, S; Kawano, Y; Shinkai, S

2017-01-01

To examine associations of dietary variety with changes in lean mass and physical performance during a 4-year period in an elderly Japanese population. Four-year prospective study. The Hatoyama Cohort Study and Kusatsu Longitudinal Study, Japan. 935 community-dwelling Japanese aged 65 years or older. Dietary variety was assessed using a 10-item food frequency questionnaire. Body composition was determined by multifrequency bioelectrical impedance analysis, and physical performance (grip strength and usual gait speed) was measured in surveys at baseline and 4 years later. Longitudinal analysis included only participants who were originally in the upper three quartiles of lean body mass, appendicular lean mass, grip strength, and usual gait speed. The outcome measures were decline in lean body mass, appendicular lean mass, grip strength, and usual gait speed, defined as a decrease to the lowest baseline quartile level at the 4-year follow-up survey. Associations of dietary variety with the outcome measures were examined by logistic regression analysis adjusted for potential confounders. In the fully adjusted model, the odds ratios for decline in grip strength and usual gait speed were 0.43 (95% confidence interval, 0.19-0.99) and 0.43 (confidence interval, 0.19-0.99), respectively, for participants in the highest category of dietary variety score as compared with those in the lowest category. Dietary variety was not significantly associated with changes in lean body mass or appendicular lean mass. Among older adults, greater dietary variety may help maintain physical performance, such as grip strength and usual gait speed, but not lean mass.

Prophylaxis usage, bleeding rates, and joint outcomes of hemophilia, 1999 to 2010: a surveillance project

PubMed Central

Soucie, J. Michael; Gill, Joan Cox

2017-01-01

This analysis of the US Hemophilia Treatment Center Network and the Centers for Disease Control and Prevention surveillance registry assessed trends in prophylaxis use and its impact on key indicators of arthropathy across the life-span among participants with severe hemophilia A. Data on demographics, clinical characteristics, and outcomes were collected prospectively between 1999 and 2010 at annual clinical visits to 134 hemophilia treatment centers. Trends in treatment and outcomes were evaluated using cross-sectional and longitudinal analyses. Data analyzed included 26 614 visits for 6196 males; mean age at first registry visit was 17.7 years; and median was 14 (range, 2 to 69). During this time, prophylaxis use increased from 31% to 59% overall, and by 2010, 75% of children and youths <20 years were on prophylaxis. On cross-sectional analysis, bleeding rates decreased dramatically for the entire population (P < .001) in parallel with increased prophylaxis usage, possibly because frequent bleeders adopted prophylaxis. Joint bleeding decreased proportionately with prophylaxis (22%) and nonprophylaxis (23%), and target joints decreased more with prophylaxis (80% vs 61%). Joint, total, and target joint bleeding on prophylaxis were 33%, 41%, and 27%, respectively, compared with nonprophylaxis. On longitudinal analysis of individuals over time, prophylaxis predicted decreased bleeding at any age (P < .001), but only prophylaxis initiation prior to age 4 years and nonobesity predicted preservation of joint motion (P < .001 for each). Using a national registry, care providers in a specialized health care network for a rare disorder were able to detect and track trends in outcomes over time. PMID:28183693

Joint models for longitudinal and time-to-event data: a review of reporting quality with a view to meta-analysis.

PubMed

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

2016-12-05

Joint models for longitudinal and time-to-event data are commonly used to simultaneously analyse correlated data in single study cases. Synthesis of evidence from multiple studies using meta-analysis is a natural next step but its feasibility depends heavily on the standard of reporting of joint models in the medical literature. During this review we aim to assess the current standard of reporting of joint models applied in the literature, and to determine whether current reporting standards would allow or hinder future aggregate data meta-analyses of model results. We undertook a literature review of non-methodological studies that involved joint modelling of longitudinal and time-to-event medical data. Study characteristics were extracted and an assessment of whether separate meta-analyses for longitudinal, time-to-event and association parameters were possible was made. The 65 studies identified used a wide range of joint modelling methods in a selection of software. Identified studies concerned a variety of disease areas. The majority of studies reported adequate information to conduct a meta-analysis (67.7% for longitudinal parameter aggregate data meta-analysis, 69.2% for time-to-event parameter aggregate data meta-analysis, 76.9% for association parameter aggregate data meta-analysis). In some cases model structure was difficult to ascertain from the published reports. Whilst extraction of sufficient information to permit meta-analyses was possible in a majority of cases, the standard of reporting of joint models should be maintained and improved. Recommendations for future practice include clear statement of model structure, of values of estimated parameters, of software used and of statistical methods applied.

Psychological risk and protective factors for disability in chronic low back pain - a longitudinal analysis in primary care.

PubMed

Jegan, Nikita Roman A; Brugger, Markus; Viniol, Annika; Strauch, Konstantin; Barth, Jürgen; Baum, Erika; Leonhardt, Corinna; Becker, Annette

2017-03-20

Utilizing psychological resources when dealing with chronic low back pain might aid the prevention of disability. The observational study at hand examined the longitudinal impact of resilience and coping resources on disability in addition to established risk factors. Four hundred eighty four patients with chronic low back pain (>3 months) were recruited in primary care practices and followed up for one year. Resilience, coping, depression, somatization, pain and demographic variables were measured at baseline. At follow-up (participation rate 89%), data on disability was collected. We first calculated bivariate correlations of all the predictors with each other and with follow-up disability. We then used a multiple regression to evaluate the impact of all the predictors on disability together. More than half of the followed up sample showed a high degree of disability at baseline (53.7%) and had suffered for more than 10 years from pain (50.4%). Besides gender all of the predictors were bivariately associated with follow-up disability. However in the main analysis (multiple regression), disability at follow up was only predicted by baseline disability, age and somatization. There was no relationship between resilience and disability, nor between coping resources and disability. Although it is known that there are cross-sectional relationships between resilience/coping resources and disability we were not able to replicate it in the multiple regression. This can have several reasons: a) the majority of patients in our sample were much more disabled and suffered for a longer time than in other studies. Therefore our results might be limited to this specific population and resilience and coping resources might still have a protective influence in acute or subacute populations. b) We used a rather broad operationalization of resilience. There is emerging evidence that focusing on more concrete sub facets like (pain) self-efficacy and acceptance might be more beneficial. German Clinical Trial Register, DRKS00003123 (June 28th 2011).

Risk of Autoimmune Disease in Adults with Chronic Insomnia Requiring Sleep-Inducing Pills: A Population-Based Longitudinal Study.

PubMed

Kok, Victor C; Horng, Jorng-Tzong; Hung, Guo-Dung; Xu, Jia-Li; Hung, Tzu-Wei; Chen, Yu-Ching; Chen, Chien-Lung

2016-09-01

Recent studies indicate that chronic insomnia is associated with the development of certain somatic diseases. Whether it would be associated with the development of an autoimmune disease (AID) was unknown. We aimed to examine the association and quantify the magnitude of risk for AID in individuals suffering from chronic insomnia requiring sleep-inducing pills. This was a population-based, nationwide longitudinal study. Using a claims data set containing 1 million randomly sampled, insured subjects derived from the National Health Insurance Research Database, we assembled a chronic insomnia group and a 1:3 propensity score-matched comparison group (CP), which were balanced in terms of sex, age, insurance premium, urbanization, alcohol use disorder, smoking-related diagnoses, and morbid obesity. Person-time data with incidence rate, adjusted hazard ratios (aHR) by the Cox model, AID-free survival functions compared with the log-rank test, and a sensitivity analysis on the time lag effect were presented. Incident AID within the first year of follow-up were excluded. The error rate was controlled using the Benjamini-Hochberg procedure. With 39,550 and 129,914 person-years' follow-up for the chronic insomnia and CP groups (n = 5,736 and 17,208), respectively, we found an increased risk for subsequent AID, representing a 70 % increase in the aHR (1.7; 95 % confidence interval [CI], 1.5-1.9, p < 0.0001). A positive association between chronic insomnia and primary Sjögren's syndrome (pSS) was observed (aHR, 1.3; 95 % CI, 1.1-1.6). Sensitivity analysis disclosed that AID risk was even stronger after 5 years of follow-up (aHR, 2.0; 95 % CI, 1.7-2.4). Chronic insomnia requiring sleep-inducing pills may be associated with a 70 % increased risk for future AID, particularly pSS.

A successful model for longitudinal community-engaged health research: the 2040 Partners for Health Student Program.

PubMed

Redman, Romany M; Reinsvold, Magdalena C; Reddy, Anireddy; Bennett, Paige E; Hoerauf, Janine M; Puls, Kristina M; Ovrutsky, Alida R; Ly, Alexandra R; White, Gregory; McNeil, Owetta; Meredith, Janet J

2017-06-01

Community-based participatory research [CBPR] is an emerging approach to collaborative research aimed at creating locally effective and sustainable interventions. The 2040 Partners for Health student program was developed as a unique model of longitudinal CBPR. Analysis of this program and its components illuminates both the challenges and the opportunities inherent in community engagement. The program rests on a foundation of a community-based, non-profit organization and a supportive academic university centre. Inter-professional health students and community members of underserved populations work together on different health projects by employing an adapted CBPR methodology. Three successful examples of sustainable CBPR projects are briefly described. The three projects are presented as primary outcomes resulting from this model. Benefits and challenges of the model as an approach to community-engaged research are discussed as well as secondary benefits of student participation. The 2040 Partners for Health student program represents a successful model of CBPR, illuminating common challenges and reiterating the profound value of community-engaged research. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Frequencies and predictors of barriers to mental health service use: a longitudinal study of Hurricane Ike survivors.

PubMed

Lowe, Sarah R; Fink, David S; Norris, Fran H; Galea, Sandro

2015-01-01

The majority of disaster survivors suffering from psychological symptoms do not receive mental health services. Research on barriers to service use among disaster survivors is limited by a lack of longitudinal studies of representative samples and investigations of predictors of barriers. The purpose of this study was to address these limitations through analysis of a three-wave population-based study of Hurricane Ike survivors (N = 658). Frequencies of preference, outcome expectancy, resource, and stigma barriers among participants with unmet mental health needs were documented and logistic regression using a generalized estimating equations approach explored predisposing (e.g., age), illness-related (e.g., posttraumatic stress) and enabling (e.g., insurance coverage) factors as predictors of each type of barrier. Preference barriers were most frequently cited at each wave, whereas stigma barriers were least frequently cited. Older age and higher emotional support predicted preference barriers; being a parent of a child under 18-years old at the time of the hurricane, higher generalized anxiety, and lack of insurance predicted resource barriers; and higher posttraumatic stress predicted stigma barriers. These findings suggest that postdisaster practices targeting subpopulations most likely to have barriers to service use may be indicated.

Longitudinal Analysis of Adolescent Girls' Activity Patterns: Understanding the Influence of the Transition to Licensure

PubMed Central

McDonald, Noreen C.; Merlin, Louis; Hu, Haoting; Shih, Joshu; Cohen, Deborah A.; Evenson, Kelly R.; McKenzie, Thomas L.; Rodriguez, Daniel A.

2016-01-01

The proportion of teens and young adults with driver's licenses has declined sharply in many industrialized countries including the United States. Explanations for this decline have ranged from the introduction of graduated driver licensing programs to the increase in online social interaction. We used a longitudinal cohort study of teenage girls in San Diego and Minneapolis to evaluate factors associated with licensure and whether teens' travel patterns become more independent as they aged. We found that licensure depended not only on age, but on race and ethnicity as well as variables that correlate with household income. Results also showed evidence that teen travel became more independent as teen's age, and that acquiring a license is an important part of this increased independence. However, we found limited evidence that teen's travel-activity patterns changed as a result of acquiring a driver's license. Rather, teen independence resulted in less parental chauffeuring, but little shift in travel patterns. For the larger debate on declining Millennial mobility, our results suggest the need for more nuanced attention to variation across demographic groups and consideration of the equity implications if declines in travel and licensure are concentrated in low-income and minority populations. PMID:28458769

Trajectories of cognitive function in dementia-free subjects: Radiation Effects Research Foundation Adult Health Study.

PubMed

Yamada, Michiko; Landes, Reid D; Mimori, Yasuyo; Nagano, Yoshito; Sasaki, Hideo

2015-04-15

To investigate associations between age, sex, education, and birth cohort and global cognitive decline among a population that would most likely not progress to dementia. A total of 1538 dementia-free subjects aged 60 to 80years in 1992 were followed up through 2011 without dementia occurrence. We assessed cognitive function using the Cognitive Ability Screening Instrument (CASI). Using stepwise-like model selection procedure, we built mixed-effects models for initial cognition and longitudinal cognition. Initial CASI scores for younger age and more years of formal education were higher than those for older and less education. Sex did not show a significant effect. In the longitudinal analysis, cognitive decline became more rapid with increasing age. Sex and education did not modify the degree of deterioration with age. CASI scores were higher for younger cohorts and men due to differences in education levels. Among dementia-free subjects, age is an important predictor of cognitive function level and cognitive decline. Education level affects cognitive function level, but did not affect cognitive decline. The results have implications not only for elucidation of the aging process, but also for reference in dementia screening. Copyright © 2015 Elsevier B.V. All rights reserved.

A Longitudinal Analysis of Antiretroviral Adherence Among Young Black Men Who Have Sex With Men.

PubMed

Voisin, Dexter R; Quinn, Katherine; Kim, Dong Ha; Schneider, John

2017-04-01

Young black men who have sex with men (YBMSM) experience poorer antiretroviral therapy (ART) medication adherence relative to their white counterparts. However, few studies have longitudinally examined factors that may correlate with various classifications of ART adherence among this population, which was the primary aim of this study. Project nGage was a randomized controlled trial conducted across five Chicago clinics from 2012 to 2015. Survey and medical records data were collected at baseline and 3- and 12-month periods to assess whether psychological distress, HIV stigma, substance use, family acceptance, social support, and self-efficacy predicted ART medication adherence among 92 YBMSM ages 16-29 years. Major results controlling for the potential effects of age, education level, employment, and intervention condition indicated that participants with high versus low medication adherence were less likely to report daily/weekly alcohol or marijuana use, had higher family acceptance, and exhibited greater self-efficacy. These findings identity important factors that can be targeted in clinical and program interventions to help improve ART medication adherence for YBMSM. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Burnout during nursing education predicts lower occupational preparedness and future clinical performance: a longitudinal study.

PubMed

Rudman, Ann; Gustavsson, J Petter

2012-08-01

Early-career burnout among nurses can influence health and professional development, as well as quality of care. However, the prospective occupational consequences of study burnout have not previously been investigated in a national sample using a longitudinal design. To prospectively monitor study burnout for a national sample of nursing students during their years in higher education and at follow-up 1 year post graduation. Further, to relate the possible development of study burnout to prospective health and life outcomes, as well as student and occupational outcomes. A longitudinal cohort of Swedish nursing students (within the population-based LANE (Longitudinal Analysis of Nursing Education/Entry) study) from all sites of education in Sweden was surveyed annually. Data were collected at four points in time over 4 years: three times during higher education and 1 year post graduation. : A longitudinal sample of 1702 respondents was prospectively followed from late autumn 2002 to spring 2006. Mean level changes of study burnout (as measured by the Oldenburg Burnout Inventory, i.e. the Exhaustion and Disengagement subscales) across time, as well as prospective effects of baseline study burnout and changes in study burnout levels, were estimated using Latent Growth Curve Modeling. An increase in study burnout (from 30% to 41%) across 3 years in higher education was found, and levels of both Exhaustion and Disengagement increased significantly across the years in education (p<0.001). Baseline levels, as well as development of study burnout, predicted lower levels of in-class learner engagement and occupational preparedness in the final year. At follow-up 1 year post graduation, earlier development of study burnout was related to lower mastery of occupational tasks, less research utilization in everyday clinical practice and higher turnover intentions. The results suggest that study burnout may have interfered with learning and psychological well-being. Aspects related to work skills and intention to leave the profession were also affected. Thus, burnout development during higher education may be an important concern, and effective preventive measures to counteract burnout development may be necessary already at the outset of nursing education. Copyright © 2012 Elsevier Ltd. All rights reserved.

Study of Mini-Mental State Exam evolution in community-dwelling subjects aged over 60 years without dementia.

PubMed

Watfa, G; Husson, N; Buatois, S; Laurain, M C; Miget, P; Benetos, A

2011-12-01

In recent years, the Mini-Mental State Examination (MMSE) has been widely used and has been proposed for cognitive decline screening in the framework of a systematic geriatric evaluation in health centers. The aim of the present longitudinal study was to identify the potential determinants of MMSE score and its evolution over a 4-year period in a population aged over sixty years with good general health without dementia and consulting for a health check-up. Longitudinal study. The preventive medical center (CMP) in Nancy. 687 subjects over 60 years of age (mean age 65.6 ± 5.07 years) were included from the Senior health examination study. All subjects underwent 2 visits over a period of 4 years. MMSE measurement and a self-administered questionnaire of emotional and psychological state were evaluated at baseline and at the follow-up visit. The major components of total variance of baseline MMSE were represented by education level, practice of regular physical activity, nervousness and despair. Multivariate analysis identified 3 variables at baseline visit that independently predicted annual changes in MMSE: MMSE score, education level and "Difficulty in social relations" (r= -0.222, 0.154 and -0.255 respectively). Education level and several psychological factors may influence MMSE score and its evolution over time in community-dwelling subjects aged over 60 years without dementia. In these subjects, a low MMSE score does not predict cognitive decline over a period of 4 years. Therefore, the reliability of MMSE in this type of population is questionable.

Two-Year Course of Generalized Anxiety Disorder, Social Anxiety Disorder and Panic Disorder with Agoraphobia in a Sample of Latino Adults

PubMed Central

Bjornsson, Andri S.; Sibrava, Nicholas J.; Beard, Courtney; Moitra, Ethan; Weisberg, Risa B.; Pérez Benítez, Carlos I.; Keller, Martin B.

2014-01-01

Objective It is imperative to study the clinical course of anxiety disorders among Latinos, given the implications for culturally-sensitive treatment in this population. The current study is the first prospective, observational, longitudinal study of anxiety disorders among Latinos. Method Data are reported on 139 adult Latinos (mean age 34.65, SD =10.98, 70.5% female) diagnosed with social anxiety disorder (SAD, n = 86), generalized anxiety disorder (GAD, n = 90) or panic disorder with agoraphobia (PDA, n = 62). The participants were interviewed with standardized clinical interviews at intake and annually over two years of follow-up. Probabilities of recovery were calculated using standard survival analysis methods. Results The two-year recovery rates in this study were 0.07 for SAD, 0.14 for GAD, 0.03 for PDA, and 0.50 for major depressive disorder (MDD). Overall functioning, social adjustment and life satisfaction in this sample were poor. Conclusions The recovery rates for anxiety disorders in this Latino sample were markedly low. Although caution must be used in comparing these data with prior longitudinal studies, these recovery rates seem to be much lower than in non-Latino White samples. However, the clinical course of MDD in this sample was similar to its course among non-Latino Whites, invoking the pressing question of whether there is something about the experience of anxiety disorders (but not MDD) among Latinos that makes them more impairing and persistent. The answer to that question should inform future treatment development for this population. PMID:24731232

Two-year course of generalized anxiety disorder, social anxiety disorder, and panic disorder with agoraphobia in a sample of Latino adults.

PubMed

Bjornsson, Andri S; Sibrava, Nicholas J; Beard, Courtney; Moitra, Ethan; Weisberg, Risa B; Benítez, Carlos I Pérez; Keller, Martin B

2014-12-01

It is imperative to study the clinical course of anxiety disorders among Latinos, given the implications for culturally sensitive treatment in this population. The current study is the first prospective, observational, longitudinal study of anxiety disorders among Latinos. Data are reported on 139 adult Latinos (M age = 34.65 years, SD = 10.98, 70.5% female) diagnosed with social anxiety disorder (SAD; n = 86), generalized anxiety disorder (GAD; n = 90), or panic disorder with agoraphobia (PDA; n = 62). The participants were interviewed with standardized clinical interviews at intake and annually over 2 years of follow-up. Probabilities of recovery were calculated using standard survival analysis methods. The 2-year recovery rates in this study were 0.07 for SAD, 0.14 for GAD, 0.03 for PDA, and 0.50 for major depressive disorder (MDD). Overall functioning, social adjustment, and life satisfaction in this sample were poor. The recovery rates for anxiety disorders in this Latino sample were markedly low. Although caution must be used in comparing these data with prior longitudinal studies, these recovery rates seem to be much lower than in non-Latino White samples. However, the clinical course of MDD in this sample was similar to its course among non-Latino Whites, invoking the pressing question of whether there is something about the experience of anxiety disorders (but not MDD) among Latinos that makes them more impairing and persistent. The answer to that question should inform future treatment development for this population.

Which modifiable health risks are associated with changes in productivity costs?

PubMed

Kirkham, Heather S; Clark, Bobby L; Bolas, Cheryl A; Lewis, Geraint Hywel; Jackson, Allison S; Fisher, Don; Duncan, Ian

2015-02-01

The purpose of this retrospective, longitudinal study was to assess longitudinal associations between modifiable health risks and workplace absenteeism and presenteeism and to estimate lost productivity costs. Across the 4-year study period (2007-2010), 17,089 unique employees from a large US computer manufacturer with a highly technical workforce completed at least 1 health risk assessment. Generalized estimating equation models were used to estimate the mean population-level absenteeism and presenteeism for 11 modifiable health risks and adjust for 9 sociodemographic and employment-related factors. Because patient age was highly correlated with several other variables, the analysis was stratified by age (<45 vs. ≥45 years). For all ages, poor emotional health, inadequate exercise, tobacco use, and having a body mass index (BMI) greater than 35 (all P<.05) were consistently associated with both absenteeism and presenteeism. Having a BMI over 35 and poor emotional health were associated with the largest impact in absenteeism (0.46 days) and presenteeism (4.03 days), respectively. Younger and older workers had similar associations between health risks and presenteeism; however, hypertension, blood sugar, inadequate exercise, and alcohol were associated (P⋜.01) with greater absenteeism among older but not younger workers. The results suggest that productivity loss is strongly related to emotional health and obesity-related health risks (eg, BMI, exercise) but differs by age. These findings could help prioritize preventive health programs offered by employers at their worksite health centers. Given the aging of the US workforce, keeping older workers healthy and productive will be crucial to remaining competitive in the global economy. (Population Health Management 2015;18:30-38).

Modelling, simulation and applications of longitudinal train dynamics

NASA Astrophysics Data System (ADS)

Cole, Colin; Spiryagin, Maksym; Wu, Qing; Sun, Yan Quan

2017-10-01

Significant developments in longitudinal train simulation and an overview of the approaches to train models and modelling vehicle force inputs are firstly presented. The most important modelling task, that of the wagon connection, consisting of energy absorption devices such as draft gears and buffers, draw gear stiffness, coupler slack and structural stiffness is then presented. Detailed attention is given to the modelling approaches for friction wedge damped and polymer draft gears. A significant issue in longitudinal train dynamics is the modelling and calculation of the input forces - the co-dimensional problem. The need to push traction performances higher has led to research and improvement in the accuracy of traction modelling which is discussed. A co-simulation method that combines longitudinal train simulation, locomotive traction control and locomotive vehicle dynamics is presented. The modelling of other forces, braking propulsion resistance, curve drag and grade forces are also discussed. As extensions to conventional longitudinal train dynamics, lateral forces and coupler impacts are examined in regards to interaction with wagon lateral and vertical dynamics. Various applications of longitudinal train dynamics are then presented. As an alternative to the tradition single wagon mass approach to longitudinal train dynamics, an example incorporating fully detailed wagon dynamics is presented for a crash analysis problem. Further applications of starting traction, air braking, distributed power, energy analysis and tippler operation are also presented.

Analysis of a Pediatric Home Mechanical Ventilator Population.

PubMed

Amirnovin, Rambod; Aghamohammadi, Sara; Riley, Carley; Woo, Marlyn S; Del Castillo, Sylvia

2018-05-01

The population of children requiring home mechanical ventilation has evolved over the years and has grown to include a variety of diagnoses and needs that have led to changes in the care of this unique population. The purpose of this study was to provide a descriptive analysis of pediatric patients requiring home mechanical ventilation after hospitalization and how the evolution of this technology has impacted their care. A retrospective, observational, longitudinal analysis of 164 children enrolled in a university-affiliated home mechanical ventilation program over 26 years was performed. Data included each child's primary diagnosis, date of tracheostomy placement, duration of mechanical ventilation during hospitalization that consisted of home mechanical ventilator initiation, total length of pediatric ICU stay, ventilator settings at time of discharge from pediatric ICU, and disposition (home, facility, or died). Univariate, bivariate, and regression analysis was used as appropriate. The most common diagnosis requiring the use of home mechanical ventilation was neuromuscular disease (53%), followed by chronic pulmonary disease (29%). The median length of stay in the pediatric ICU decreased significantly after the implementation of a ventilator ward (70 d [30-142] vs 36 d [18-67], P = .02). The distribution of subjects upon discharge was home (71%), skilled nursing facility (24%), and died (4%), with an increase in the proportion of subjects discharged on PEEP and those going to nursing facilities over time ( P = 0.02). The evolution of home mechanical ventilation has allowed earlier transition out of the pediatric ICU and with increasing disposition to skilled nursing facilities over time. There has also been a change in ventilator management, including increased use of PEEP upon discharge, possibly driven by changes in ventilators and in-patient practice patterns. Copyright © 2018 by Daedalus Enterprises.

Effects of Computer Support, Collaboration, and Time Lag on Performance Self-Efficacy and Transfer of Training: A Longitudinal Meta-Analysis

ERIC Educational Resources Information Center

Gegenfurtner, Andreas; Veermans, Koen; Vauras, Marja

2013-01-01

This meta-analysis (29 studies, k = 33, N = 4158) examined the longitudinal development of the relationship between performance self-efficacy and transfer before and after training. A specific focus was on training programs that afforded varying degrees of computer-supported collaborative learning (CSCL). Consistent with social cognitive theory,…

The Developmental and Cultural Contexts of Objectified Body Consciousness: A Longitudinal Analysis of Two Cohorts of Women

ERIC Educational Resources Information Center

McKinley, Nita Mary

2006-01-01

Longitudinal analysis of 10-year follow-up data on objectified body consciousness, body esteem, weight-related attitudes and behaviors, and psychological well-being in 74 middle-aged and 72 young women tested hypotheses developed from age-related change and cohort differences models of body experience. Young women's body surveillance and body…

Decreasing Sports Activity with Increasing Age? Findings from a 20-Year Longitudinal and Cohort Sequence Analysis

ERIC Educational Resources Information Center

Breuer, Christoph; Wicker, Pamela

2009-01-01

According to cross-sectional studies in sport science literature, decreasing sports activity with increasing age is generally assumed. In this paper, the validity of this assumption is checked by applying more effective methods of analysis, such as longitudinal and cohort sequence analyses. With the help of 20 years' worth of data records from the…

Evolution of Online Discussion Forum Richness according to Channel Expansion Theory: A Longitudinal Panel Data Analysis

ERIC Educational Resources Information Center

Fernandez, Vicenc; Simo, Pep; Sallan, Jose M.; Enache, Mihaela

2013-01-01

The selection and use of communication media has been the center of attention for a great number of researchers in the area of organizational communication. The channel expansion theory combines elements of the main theories in this area; however, these investigations have a static cross-sectional design rather than a longitudinal analysis. With…

Neighborhood archetypes for population health research: is there no place like home?

PubMed

Weden, Margaret M; Bird, Chloe E; Escarce, José J; Lurie, Nicole

2011-01-01

This study presents a new, latent archetype approach for studying place in population health. Latent class analysis is used to show how the number, defining attributes, and change/stability of neighborhood archetypes can be characterized and tested for statistical significance. The approach is demonstrated using data on contextual determinants of health for US neighborhoods defined by census tracts in 1990 and 2000. Six archetypes (prevalence 13-20%) characterize the statistically significant combinations of contextual determinants of health from the social environment, built environment, commuting and migration patterns, and demographics and household composition of US neighborhoods. Longitudinal analyses based on the findings demonstrate notable stability (76.4% of neighborhoods categorized as the same archetype ten years later), with exceptions reflecting trends in (ex)urbanization, gentrification/downgrading, and racial/ethnic reconfiguration. The findings and approach is applicable to both research and practice (e.g. surveillance) and can be scaled up or down to study health and place in other geographical contexts or historical periods. Copyright © 2010 Elsevier Ltd. All rights reserved.

A stochastic step model of replicative senescence explains ROS production rate in ageing cell populations.

PubMed

Lawless, Conor; Jurk, Diana; Gillespie, Colin S; Shanley, Daryl; Saretzki, Gabriele; von Zglinicki, Thomas; Passos, João F

2012-01-01

Increases in cellular Reactive Oxygen Species (ROS) concentration with age have been observed repeatedly in mammalian tissues. Concomitant increases in the proportion of replicatively senescent cells in ageing mammalian tissues have also been observed. Populations of mitotic human fibroblasts cultured in vitro, undergoing transition from proliferation competence to replicative senescence are useful models of ageing human tissues. Similar exponential increases in ROS with age have been observed in this model system. Tracking individual cells in dividing populations is difficult, and so the vast majority of observations have been cross-sectional, at the population level, rather than longitudinal observations of individual cells.One possible explanation for these observations is an exponential increase in ROS in individual fibroblasts with time (e.g. resulting from a vicious cycle between cellular ROS and damage). However, we demonstrate an alternative, simple hypothesis, equally consistent with these observations which does not depend on any gradual increase in ROS concentration: the Stochastic Step Model of Replicative Senescence (SSMRS). We also demonstrate that, consistent with the SSMRS, neither proliferation-competent human fibroblasts of any age, nor populations of hTERT overexpressing human fibroblasts passaged beyond the Hayflick limit, display high ROS concentrations. We conclude that longitudinal studies of single cells and their lineages are now required for testing hypotheses about roles and mechanisms of ROS increase during replicative senescence.

A Stochastic Step Model of Replicative Senescence Explains ROS Production Rate in Ageing Cell Populations

PubMed Central

Lawless, Conor; Jurk, Diana; Gillespie, Colin S.; Shanley, Daryl; Saretzki, Gabriele; von Zglinicki, Thomas; Passos, João F.

2012-01-01

Increases in cellular Reactive Oxygen Species (ROS) concentration with age have been observed repeatedly in mammalian tissues. Concomitant increases in the proportion of replicatively senescent cells in ageing mammalian tissues have also been observed. Populations of mitotic human fibroblasts cultured in vitro, undergoing transition from proliferation competence to replicative senescence are useful models of ageing human tissues. Similar exponential increases in ROS with age have been observed in this model system. Tracking individual cells in dividing populations is difficult, and so the vast majority of observations have been cross-sectional, at the population level, rather than longitudinal observations of individual cells. One possible explanation for these observations is an exponential increase in ROS in individual fibroblasts with time (e.g. resulting from a vicious cycle between cellular ROS and damage). However, we demonstrate an alternative, simple hypothesis, equally consistent with these observations which does not depend on any gradual increase in ROS concentration: the Stochastic Step Model of Replicative Senescence (SSMRS). We also demonstrate that, consistent with the SSMRS, neither proliferation-competent human fibroblasts of any age, nor populations of hTERT overexpressing human fibroblasts passaged beyond the Hayflick limit, display high ROS concentrations. We conclude that longitudinal studies of single cells and their lineages are now required for testing hypotheses about roles and mechanisms of ROS increase during replicative senescence. PMID:22359661

Long-term benefits of full-day kindergarten: a longitudinal population-based study

PubMed Central

Brownell, M.D.; Nickel, N.C.; Chateau, D.; Martens, P.J.; Taylor, C.; Crockett, L.; Katz, A.; Sarkar, J.; Burland, E.; Goh, C.Y.

2015-01-01

In the first longitudinal, population-based study of full-day kindergarten (FDK) outcomes beyond primary school in Canada, we used linked administrative data to follow 15 kindergarten cohorts (n ranging from 112 to 736) up to grade 9. Provincial assessments conducted in grades 3, 7, and 8 and course marks and credits earned in grade 9 were compared between FDK and half-day kindergarten (HDK) students in both targeted and universal FDK programmes. Propensity score matched cohort and stepped-wedge designs allowed for stronger causal inferences than previous research on FDK. We found limited long-term benefits of FDK, specific to the type of programme, outcomes examined, and subpopulations. FDK programmes targeted at low-income areas showed long-term improvements in numeracy for lower income girls. Our results suggest that expectations for wide-ranging long-term academic benefits of FDK are unwarranted. PMID:25632172