ERIC Educational Resources Information Center
Steel, Jennifer L.; Herlitz, Claes A.
2005-01-01
Objective: Several studies with small and ''high risk'' samples have demonstrated that a history of childhood or adolescent sexual abuse (CASA) is associated with sexual risk behaviors (SRBs). However, few studies with large random samples from the general population have specifically examined the relationship between CASA and SRBs with a…
Assessing the Generalizability of Randomized Trial Results to Target Populations
Stuart, Elizabeth A.; Bradshaw, Catherine P.; Leaf, Philip J.
2014-01-01
Recent years have seen increasing interest in and attention to evidence-based practices, where the “evidence” generally comes from well-conducted randomized trials. However, while those trials yield accurate estimates of the effect of the intervention for the participants in the trial (known as “internal validity”), they do not always yield relevant information about the effects in a particular target population (known as “external validity”). This may be due to a lack of specification of a target population when designing the trial, difficulties recruiting a sample that is representative of a pre-specified target population, or to interest in considering a target population somewhat different from the population directly targeted by the trial. This paper first provides an overview of existing design and analysis methods for assessing and enhancing the ability of a randomized trial to estimate treatment effects in a target population. It then provides a case study using one particular method, which weights the subjects in a randomized trial to match the population on a set of observed characteristics. The case study uses data from a randomized trial of School-wide Positive Behavioral Interventions and Supports (PBIS); our interest is in generalizing the results to the state of Maryland. In the case of PBIS, after weighting, estimated effects in the target population were similar to those observed in the randomized trial. The paper illustrates that statistical methods can be used to assess and enhance the external validity of randomized trials, making the results more applicable to policy and clinical questions. However, there are also many open research questions; future research should focus on questions of treatment effect heterogeneity and further developing these methods for enhancing external validity. Researchers should think carefully about the external validity of randomized trials and be cautious about extrapolating results to specific populations unless they are confident of the similarity between the trial sample and that target population. PMID:25307417
Assessing the generalizability of randomized trial results to target populations.
Stuart, Elizabeth A; Bradshaw, Catherine P; Leaf, Philip J
2015-04-01
Recent years have seen increasing interest in and attention to evidence-based practices, where the "evidence" generally comes from well-conducted randomized trials. However, while those trials yield accurate estimates of the effect of the intervention for the participants in the trial (known as "internal validity"), they do not always yield relevant information about the effects in a particular target population (known as "external validity"). This may be due to a lack of specification of a target population when designing the trial, difficulties recruiting a sample that is representative of a prespecified target population, or to interest in considering a target population somewhat different from the population directly targeted by the trial. This paper first provides an overview of existing design and analysis methods for assessing and enhancing the ability of a randomized trial to estimate treatment effects in a target population. It then provides a case study using one particular method, which weights the subjects in a randomized trial to match the population on a set of observed characteristics. The case study uses data from a randomized trial of school-wide positive behavioral interventions and supports (PBIS); our interest is in generalizing the results to the state of Maryland. In the case of PBIS, after weighting, estimated effects in the target population were similar to those observed in the randomized trial. The paper illustrates that statistical methods can be used to assess and enhance the external validity of randomized trials, making the results more applicable to policy and clinical questions. However, there are also many open research questions; future research should focus on questions of treatment effect heterogeneity and further developing these methods for enhancing external validity. Researchers should think carefully about the external validity of randomized trials and be cautious about extrapolating results to specific populations unless they are confident of the similarity between the trial sample and that target population.
Ulfberg, J; Carter, N; Talbäck, M; Edling, C
1996-09-01
To evaluate excessive daytime sleepiness (EDS) at work and effects on reported work performance among men in the general population and male patients suffering from snoring and obstructive sleep apnea syndrome (OSAS). A cross-sectional study of Swedish men between the ages of 30 and 64 years in the county of Kopparberg, in mid-Sweden. A random sample of the general population (n = 285) and consecutive patients referred to a sleep laboratory who fulfilled objective diagnostic criteria (snorers = 289, OSAS = 62) responded to a questionnaire. Responders from the general population were divided into 2 groups, nonsnorers (n = 223) and snorers (n = 62). To validate a question on snoring in the questionnaire, 50 men, randomly selected from the sample of the general population, underwent sleep apnea screening in their homes. The specificity of the questions about snoring was 83% and the sensitivity was 42%. The risk ratios for reporting EDS at work were 4-fold for snorers in the general population, 20-fold for snoring patients, and 40-fold for patients with OSAS as compared with nonsnoring men in the general population. Patients with OSAS and snoring patients both showed increased ratios on measures of difficulties with concentration, learning new tasks, and performing monotonous tasks when compared with nonsnorers. Snoring and sleep apnea were highly associated with excessive EDS at work and subjective work performance problems. The results provide additional evidence that snoring is not merely a nuisance.
Scott, JoAnna M; deCamp, Allan; Juraska, Michal; Fay, Michael P; Gilbert, Peter B
2017-04-01
Stepped wedge designs are increasingly commonplace and advantageous for cluster randomized trials when it is both unethical to assign placebo, and it is logistically difficult to allocate an intervention simultaneously to many clusters. We study marginal mean models fit with generalized estimating equations for assessing treatment effectiveness in stepped wedge cluster randomized trials. This approach has advantages over the more commonly used mixed models that (1) the population-average parameters have an important interpretation for public health applications and (2) they avoid untestable assumptions on latent variable distributions and avoid parametric assumptions about error distributions, therefore, providing more robust evidence on treatment effects. However, cluster randomized trials typically have a small number of clusters, rendering the standard generalized estimating equation sandwich variance estimator biased and highly variable and hence yielding incorrect inferences. We study the usual asymptotic generalized estimating equation inferences (i.e., using sandwich variance estimators and asymptotic normality) and four small-sample corrections to generalized estimating equation for stepped wedge cluster randomized trials and for parallel cluster randomized trials as a comparison. We show by simulation that the small-sample corrections provide improvement, with one correction appearing to provide at least nominal coverage even with only 10 clusters per group. These results demonstrate the viability of the marginal mean approach for both stepped wedge and parallel cluster randomized trials. We also study the comparative performance of the corrected methods for stepped wedge and parallel designs, and describe how the methods can accommodate interval censoring of individual failure times and incorporate semiparametric efficient estimators.
Headache, snoring and sleep apnoea.
Ulfberg, J; Carter, N; Talbäck, M; Edling, C
1996-09-01
To evaluate reported headache prevalence among the general population and patients suffering from snoring and obstructive sleep apnoea syndrome (OSAS), a cross-sectional study was performed among those aged 30-64 years residing in Kopparberg county in central Sweden. Consecutive patients referred to the sleep laboratory in the catchment area who fulfilled objective diagnostic criteria (snorers = 448, OSAS = 324) and a random sample of the general population (n = 583) responded to the same questionnaire. Patients were selected following sleep apnoea screening with 100% specificity for both OSAS and snoring. Responders from the general population were divided into snorers or non-snorers on the basis of self-report. To validate the self-report question on snoring in the questionnaire, 50 males and 49 females, randomly selected from the sample of the general population, underwent sleep apnoea screening in their homes. Headache among both men and women was found to be more prevalent among heavy snorers and OSAS patients compared with the control group. Morning headache, in particular, was at least three times more common among male and female heavy snorers and OSAS patients then among the general population. Headache in the control group was more common among snorers than non-snorers. Among responders, 5% of the general population reported experiencing headache often or very often upon awakening. For the heavy snoring and OSAS groups, 18% reported experiencing headache often or very often upon awakening. The results indicate that headache is common among heavy snorers and OSAS patients regardless of gender.
Mullally, B J; Greiner, B A; Allwright, S; Paul, G; Perry, I J
2008-12-01
This study establishes baseline prevalence of smoking and cigarette consumption among Cork bar workers prior to the Republic of Ireland's (ROI) smokefree workplace legislation and compares gender- and age-specific smoking rates and estimates the adjusted odds of being a smoker for Cork bar workers relative to the general population. Cross-sectional random sample of bar workers in Cork city and cross-sectional random telephone survey of the general population were conducted prior to the smokefree legislation. Self reported smoking prevalence among Cork bar workers (n = 129) was 54% (58% using cotinine-validated measures), with particularly high rates in women (70%) and 18-28 years old (72%). Within the ROI (n = 1,240) sub-sample rates were substantially lower at 28%. Bar workers were twice as likely to be smokers as the general population sub-sample (OR = 2.15). Cork bar workers constitute an occupational group with an extremely high smoking prevalence.
General Population Norms about Child Abuse and Neglect and Associations with Childhood Experiences
ERIC Educational Resources Information Center
Bensley, L.; Ruggles, D.; Simmons, K.W.; Harris, C.; Williams, K.; Putvin, T.; Allen, M.
2004-01-01
Background:: A variety of definitions of child abuse and neglect exist. However, little is known about norms in the general population as to what constitutes child abuse and neglect or how perceived norms may be related to personal experiences. Methods:: We conducted a random-digit-dialed telephone survey of 504 Washington State adults.…
ERIC Educational Resources Information Center
Chan, Julia Y. K.; Bauer, Christopher F.
2015-01-01
This study investigated exam achievement and affective characteristics of students in general chemistry in a fully-randomized experimental design, contrasting Peer-Led Team Learning (PLTL) participation with a control group balanced for time-on-task and study activity. This study population included two independent first-semester courses with…
ERIC Educational Resources Information Center
Tipton, Elizabeth
2013-01-01
As a result of the use of random assignment to treatment, randomized experiments typically have high internal validity. However, units are very rarely randomly selected from a well-defined population of interest into an experiment; this results in low external validity. Under nonrandom sampling, this means that the estimate of the sample average…
Estimating the Variance of Design Parameters
ERIC Educational Resources Information Center
Hedberg, E. C.; Hedges, L. V.; Kuyper, A. M.
2015-01-01
Randomized experiments are generally considered to provide the strongest basis for causal inferences about cause and effect. Consequently randomized field trials have been increasingly used to evaluate the effects of education interventions, products, and services. Populations of interest in education are often hierarchically structured (such as…
Estimation of population mean under systematic sampling
NASA Astrophysics Data System (ADS)
Noor-ul-amin, Muhammad; Javaid, Amjad
2017-11-01
In this study we propose a generalized ratio estimator under non-response for systematic random sampling. We also generate a class of estimators through special cases of generalized estimator using different combinations of coefficients of correlation, kurtosis and variation. The mean square errors and mathematical conditions are also derived to prove the efficiency of proposed estimators. Numerical illustration is included using three populations to support the results.
LETTER TO THE EDITOR: Mixed population Minority Game with generalized strategies
NASA Astrophysics Data System (ADS)
Jefferies, P.; Hart, M.; Johnson, N. F.; Hui, P. M.
2000-11-01
We present a quantitative theory, based on crowd effects, for the market volatility in a Minority Game played by a mixed population. Below a critical concentration of generalized strategy players, we find that the volatility in the crowded regime remains above the random coin-toss value regardless of the `temperature' controlling strategy use. Our theory yields good agreement with numerical simulations.
Population density equations for stochastic processes with memory kernels
NASA Astrophysics Data System (ADS)
Lai, Yi Ming; de Kamps, Marc
2017-06-01
We present a method for solving population density equations (PDEs)-a mean-field technique describing homogeneous populations of uncoupled neurons—where the populations can be subject to non-Markov noise for arbitrary distributions of jump sizes. The method combines recent developments in two different disciplines that traditionally have had limited interaction: computational neuroscience and the theory of random networks. The method uses a geometric binning scheme, based on the method of characteristics, to capture the deterministic neurodynamics of the population, separating the deterministic and stochastic process cleanly. We can independently vary the choice of the deterministic model and the model for the stochastic process, leading to a highly modular numerical solution strategy. We demonstrate this by replacing the master equation implicit in many formulations of the PDE formalism by a generalization called the generalized Montroll-Weiss equation—a recent result from random network theory—describing a random walker subject to transitions realized by a non-Markovian process. We demonstrate the method for leaky- and quadratic-integrate and fire neurons subject to spike trains with Poisson and gamma-distributed interspike intervals. We are able to model jump responses for both models accurately to both excitatory and inhibitory input under the assumption that all inputs are generated by one renewal process.
Carter, Marissa J; Fife, Caroline E; Walker, David; Thomson, Brett
2009-07-01
To determine the percentage of individuals that would be excluded from wound care randomized controlled trials (RCTs) as a surrogate for applicability to general populations. A representative sample of wound-care RCTs was selected from the literature in the past 10 years. Exclusion criteria from the trials were evaluated, and prevalence values for each excluded condition were obtained from a large wound-care population, as well as from the literature. The percentage of patients excluded on this basis was calculated. Seventeen RCTs testing "high-technology" wound-care products were evaluated. : Patients in the trials were treated for ulcers (venous, diabetic foot, and pressure ulcers). A percentage of patients in the study population were excluded for each RCT. More than 50% of the study population would have been excluded in 15 of the 17 RCTs. When less clinically relevant exclusion criteria were removed, 14 of 17 RCTs would still have excluded between 25% and 50% of the study population. The results raise serious questions regarding the applicability of these RCTs to wound-care populations.
Lotka-Volterra system in a random environment.
Dimentberg, Mikhail F
2002-03-01
Classical Lotka-Volterra (LV) model for oscillatory behavior of population sizes of two interacting species (predator-prey or parasite-host pairs) is conservative. This may imply unrealistically high sensitivity of the system's behavior to environmental variations. Thus, a generalized LV model is considered with the equation for preys' reproduction containing the following additional terms: quadratic "damping" term that accounts for interspecies competition, and term with white-noise random variations of the preys' reproduction factor that simulates the environmental variations. An exact solution is obtained for the corresponding Fokker-Planck-Kolmogorov equation for stationary probability densities (PDF's) of the population sizes. It shows that both population sizes are independent gamma-distributed stationary random processes. Increasing level of the environmental variations does not lead to extinction of the populations. However it may lead to an intermittent behavior, whereby one or both population sizes experience very rare and violent short pulses or outbreaks while remaining on a very low level most of the time. This intermittency is described analytically by direct use of the solutions for the PDF's as well as by applying theory of excursions of random functions and by predicting PDF of peaks in the predators' population size.
Lotka-Volterra system in a random environment
NASA Astrophysics Data System (ADS)
Dimentberg, Mikhail F.
2002-03-01
Classical Lotka-Volterra (LV) model for oscillatory behavior of population sizes of two interacting species (predator-prey or parasite-host pairs) is conservative. This may imply unrealistically high sensitivity of the system's behavior to environmental variations. Thus, a generalized LV model is considered with the equation for preys' reproduction containing the following additional terms: quadratic ``damping'' term that accounts for interspecies competition, and term with white-noise random variations of the preys' reproduction factor that simulates the environmental variations. An exact solution is obtained for the corresponding Fokker-Planck-Kolmogorov equation for stationary probability densities (PDF's) of the population sizes. It shows that both population sizes are independent γ-distributed stationary random processes. Increasing level of the environmental variations does not lead to extinction of the populations. However it may lead to an intermittent behavior, whereby one or both population sizes experience very rare and violent short pulses or outbreaks while remaining on a very low level most of the time. This intermittency is described analytically by direct use of the solutions for the PDF's as well as by applying theory of excursions of random functions and by predicting PDF of peaks in the predators' population size.
Paranormal experiences in the general population.
Ross, C A; Joshi, S
1992-06-01
The Dissociative Disorders Interview Schedule was administered to a random sample of 502 adults in the general population of Winnipeg, a midwestern Canadian city. Results showed that paranormal/extrasensory experiences were common in the general population. They were linked to a history of childhood trauma and to other dissociative symptom clusters. A factor analysis of the paranormal experiences identified three factors which together accounted for 44.0% of the combined variance of the scores. A model is proposed in which paranormal experiences are conceptualized as an aspect of normal dissociation. Like dissociation in general, paranormal experiences can be triggered by trauma, especially childhood physical or sexual abuse. Such experiences discriminate individuals with childhood trauma histories from those without at high levels of significance.
[CardiReset: general medicine and monitoring of cardiovascular risk factors in a whole region].
Vanuzzo, Diego; Samani, Fabio; Canciani, Luigi; Paduano, Romano; Pilotto, Lorenza; Bader, Giovanni; Mirolo, Renata; Battigelli, Doriano; Panfilo, Marina; Fattori, Maria Grazia; Simon, Giorgio; Zanier, Loris
2009-01-01
The CardioRESET project was carried out in 2005 to evaluate the feasibility of a cardiovascular risk factor survey by general practitioners in Friuli Venezia Giulia, a north-eastern Italian region. We randomized 2701 subjects (1336 males and 1365 females), aged 35-74 years, from the general population. The family doctors surveyed the randomized population sample using the standardized methods of the Osservatorio Epidemiologico Cardiovascolare, a reference national survey. The participation rate was 85.4% and all variables were recorded at least in 60% of subjects. Mean values of risk factors, prevalence of hypertension, dyslipidemia, diabetes and data on their control, smoking habits were comparable with data from the Osservatorio Epidemiologico Cardiovascolare; only the mean value of low-density lipoprotein cholesterolemia was higher in our region. This experience points out that in a small region it is possible to engage general practitioners to achieve a standardized surveillance of cardiovascular risk factors at a low cost.
Site Selection in Experiments: A Follow-Up Evaluation of Site Recruitment in Two Scale-Up Studies
ERIC Educational Resources Information Center
Tipton, Elizabeth; Fellers, Lauren; Caverly, Sarah; Vaden-Kiernan, Michael; Borman, Geoffrey; Sullivan, Kate; Ruiz de Castillo, Veronica
2015-01-01
Randomized experiments are commonly used to evaluate if particular interventions improve student achievement. While these experiments can establish that a treatment actually "causes" changes, typically the participants are not randomly selected from a well-defined population and therefore the results do not readily generalize. Three…
Norekvål, Tone M; Wahl, Astrid K; Fridlund, Bengt; Nordrehaug, Jan E; Wentzel-Larsen, Tore; Hanestad, Berit R
2007-10-30
A substantial burden associated with MI has been reported. Thus, how survivors experience their quality of life (QOL) is now being given increasing attention. However, few studies have involved women and a comparison with the general population. The aims of this study were to determine the QOL of female MI survivors, to investigate whether their QOL differed from that of the general population, and to evaluate the clinical significance of the findings. Two cross-sectional surveys were performed; on female MI survivors and the general Norwegian population. The MI survey included women aged 62-80 years, three months to five years after their MI. One hundred and forty-five women responded, yielding a response rate of 60%. A subset of women in the same age range (n = 156) was drawn from a study of 1893 randomly selected Norwegian citizens. QOL was measured in both groups with the World Health Organization Quality of Life Instrument Abbreviated (WHOQOL-BREF). The majority (54%) of the female MI survivors presented with ST-elevation in their ECG, 31% received thrombolysis, and 38% had reduced left ventricular ejection fraction. Female MI survivors reported significantly lower satisfaction with general health (p = 0.020) and overall QOL (p = 0.017) than women from the general population. This was also the case for the physical and environmental QOL domains (p < 0.001), but not for the psychological and social relationship domains. Estimated effect sizes between the two groups of participants ranged from 0.1 to -0.6. The burden of MI significantly affects the physical health of elderly women. Still, female MI survivors fare as well as the general female population on psychosocial QOL domains. Action should be taken not only to support women's physical needs but also to reinforce their strengths in order to maintain optimal QOL.
Norekvål, Tone M; Wahl, Astrid K; Fridlund, Bengt; Nordrehaug, Jan E; Wentzel-Larsen, Tore; Hanestad, Berit R
2007-01-01
Background A substantial burden associated with MI has been reported. Thus, how survivors experience their quality of life (QOL) is now being given increasing attention. However, few studies have involved women and a comparison with the general population. The aims of this study were to determine the QOL of female MI survivors, to investigate whether their QOL differed from that of the general population, and to evaluate the clinical significance of the findings. Methods Two cross-sectional surveys were performed; on female MI survivors and the general Norwegian population. The MI survey included women aged 62–80 years, three months to five years after their MI. One hundred and forty-five women responded, yielding a response rate of 60%. A subset of women in the same age range (n = 156) was drawn from a study of 1893 randomly selected Norwegian citizens. QOL was measured in both groups with the World Health Organization Quality of Life Instrument Abbreviated (WHOQOL-BREF). Results The majority (54%) of the female MI survivors presented with ST-elevation in their ECG, 31% received thrombolysis, and 38% had reduced left ventricular ejection fraction. Female MI survivors reported significantly lower satisfaction with general health (p = 0.020) and overall QOL (p = 0.017) than women from the general population. This was also the case for the physical and environmental QOL domains (p < 0.001), but not for the psychological and social relationship domains. Estimated effect sizes between the two groups of participants ranged from 0.1 to -0.6. Conclusion The burden of MI significantly affects the physical health of elderly women. Still, female MI survivors fare as well as the general female population on psychosocial QOL domains. Action should be taken not only to support women's physical needs but also to reinforce their strengths in order to maintain optimal QOL. PMID:17971206
Single-Phase Mail Survey Design for Rare Population Subgroups
ERIC Educational Resources Information Center
Brick, J. Michael; Andrews, William R.; Mathiowetz, Nancy A.
2016-01-01
Although using random digit dialing (RDD) telephone samples was the preferred method for conducting surveys of households for many years, declining response and coverage rates have led researchers to explore alternative approaches. The use of address-based sampling (ABS) has been examined for sampling the general population and subgroups, most…
Assessing Methods for Generalizing Experimental Impact Estimates to Target Populations
ERIC Educational Resources Information Center
Kern, Holger L.; Stuart, Elizabeth A.; Hill, Jennifer; Green, Donald P.
2016-01-01
Randomized experiments are considered the gold standard for causal inference because they can provide unbiased estimates of treatment effects for the experimental participants. However, researchers and policymakers are often interested in using a specific experiment to inform decisions about other target populations. In education research,…
Smith, Blair H; Hannaford, Philip C; Elliott, Alison M; Smith, W Cairns; Chambers, W Alastair
2005-04-01
Sampling for primary care research must strike a balance between efficiency and external validity. For most conditions, even a large population sample will yield a small number of cases, yet other sampling techniques risk problems with extrapolation of findings. To compare the efficiency and external validity of two sampling methods for both an intervention study and epidemiological research in primary care--a convenience sample and a general population sample--comparing the response and follow-up rates, the demographic and clinical characteristics of each sample, and calculating the 'number needed to sample' (NNS) for a hypothetical randomized controlled trial. In 1996, we selected two random samples of adults from 29 general practices in Grampian, for an epidemiological study of chronic pain. One sample of 4175 was identified by an electronic questionnaire that listed patients receiving regular analgesic prescriptions--the 'repeat prescription sample'. The other sample of 5036 was identified from all patients on practice lists--the 'general population sample'. Questionnaires, including demographic, pain and general health measures, were sent to all. A similar follow-up questionnaire was sent in 2000 to all those agreeing to participate in further research. We identified a potential group of subjects for a hypothetical trial in primary care based on a recently published trial (those aged 25-64, with severe chronic back pain, willing to participate in further research). The repeat prescription sample produced better response rates than the general sample overall (86% compared with 82%, P < 0.001), from both genders and from the oldest and youngest age groups. The NNS using convenience sampling was 10 for each member of the final potential trial sample, compared with 55 using general population sampling. There were important differences between the samples in age, marital and employment status, social class and educational level. However, among the potential trial sample, there were no demographic differences. Those from the repeat prescription sample had poorer indices than the general population sample in all pain and health measures. The repeat prescription sampling method was approximately five times more efficient than the general population method. However demographic and clinical differences in the repeat prescription sample might hamper extrapolation of findings to the general population, particularly in an epidemiological study, and demonstrate that simple comparison with age and gender of the target population is insufficient.
ERIC Educational Resources Information Center
Smith, Douglas C.; Lanesskog, Deirdre; Cleeland, Leah; Motl, Robert; Weikert, Madeline; Dlugonski, Deirdre
2012-01-01
People with multiple sclerosis (MS) are likely to benefit from regular exercise, but physical inactivity is more common among people with MS than among the general population. This small randomized study evaluated whether motivational interviewing (MI) affects adherence to and personal experience in an exercise program. Inactive people with MS…
ERIC Educational Resources Information Center
Ptomey, Lauren T.; Saunders, Richard R.; Saunders, Muriel; Washburn, Richard A.; Mayo, Matthew S.; Sullivan, Debra K.; Gibson, Cheryl A.; Goetz, Jeannine R.; Honas, Jeff J.; Willis, Erik A.; Danon, Jessica C.; Krebill, Ron; Donnelly, Joseph E.
2018-01-01
Background: The prevalence of obesity among individuals with intellectual and developmental disabilities (IDD) is equal to or greater than the general population. Methods: Overweight/obese adults (BMI =25 kg/m2) with mild-to-moderate intellectual and developmental disabilities were randomized to an enhanced stop light diet…
Yun, Young Ho; Sim, Jin Ah; Park, Eun-Gee; Park, June Dong; Noh, Dong-Young
2016-09-01
To perform a comparison between health behaviors and health status of employees with those of the general population, to evaluate the association between employee health behaviors, health status, and absenteeism. Cross-sectional study enrolled 2433 employees from 16 Korean companies in 2014, and recruited 1000 general population randomly in 2012. The distribution of employee health behaviors, health status, and association with absenteeism were assessed. Employees had significantly worse health status and low rates of health behaviors maintenance compared with the general population. Multiple logistic regression model revealed that regular exercise, smoking cessation, work life balance, proactive living, religious practice, and good physical health status were associated with lower absenteeism. Maintaining health behaviors and having good health status were associated with less absenteeism. This study suggests investment of multidimensional health approach in workplace health and wellness (WHW) programs.
Baseline Characteristics of Participants in the Randomized National Lung Screening Trial
Aberle, Denise R.; Adams, Amanda M.; Berg, Christine D.; Clapp, Jonathan D.; Clingan, Kathy L.; Gareen, Ilana F.; Marcus, Pamela M.; Pinsky, Paul F.
2010-01-01
Background The National Lung Screening Trial (NLST), a randomized study conducted at 33 US sites, is comparing lung cancer mortality among persons screened with reduced dose helical computerized tomography and among persons screened with chest radiograph. In this article, we present characteristics of the study population. Methods Eligible participants were aged 55–74 years and were current or former smokers with a cigarette smoking history of at least 30 pack-years. Randomization was stratified by site, sex, and age. To assess representativeness of the study population, demographic characteristics of individuals from the general population who met NLST age and smoking history inclusion criteria were obtained from the Tobacco Use Supplement of the US Census Bureau Current Population Surveys. Results The NLST enrolled 53 456 persons, with 26 733 randomly assigned to chest radiograph screening and 26 723 to computerized tomography screening. Characteristics of the participants were as follows: 31 533 (59%) were men, 39 234 (73%) were younger than 65 years, 25 779 (48%) were current smokers, and 16 839 (32%) had a college or higher degree. Median cigarette exposure was 48 pack-years. Among Tobacco Use Supplement respondents who met NLST age and smoking history criteria, 59% were men, 65% were younger than 65 years, and 57% were current smokers. Median cigarette exposure among this group was 47 pack-years, and 14% had a college degree or higher. Conclusion The NLST cohort has a distribution of sex and pack-year history that is similar to the component of the general US population that meets the major NLST eligibility criteria; however, NLST participants are younger, better educated, and less likely to be current smokers. PMID:21119104
Lung, Tom W. C.; Hayes, Alison J.; Herman, William H.; Si, Lei; Palmer, Andrew J.; Clarke, Philip M.
2014-01-01
Aims Type 1 diabetes has been associated with an elevated relative risk (RR) of mortality compared to the general population. To review published studies on the RR of mortality of Type 1 diabetes patients compared to the general population, we conducted a meta-analysis and examined the temporal changes in the RR of mortality over time. Methods Systematic review of studies reporting RR of mortality for Type 1 diabetes compared to the general population. We conducted meta-analyses using a DerSimonian and Laird random effects model to obtain the average effect and the distribution of RR estimates. Sub-group meta-analyses and multivariate meta-regression analysis was performed to examine heterogeneity. Summary RR with 95% CIs was calculated using a random-effects model. Results 26 studies with a total of 88 subpopulations were included in the meta-analysis and overall RR of mortality was 3.82 (95% CI 3.41, 3.4.29) compared to the general population. Observations using data prior to 1971 had a much larger estimated RR (5.80 (95% CI 4.20, 8.01)) when compared to: data between; 1971 and 1980 (5.06 (95% CI 3.44, 7.45)); 1981–90 (3.59 (95% CI 3.15, 4.09)); and those after 1990 (3.11 (95% CI 2.47, 3.91)); suggesting mortality of Type 1 diabetes patients when compared to the general population have been improving over time. Similarly, females (4.54 (95% CI 3.79–5.45)) had a larger RR estimate when compared to males (3.25 (95% CI 2.82–3.73) and the meta-regression found evidence for temporal trends and sex (p<0.01) accounting for heterogeneity between studies. Conclusions Type 1 diabetes patients’ mortality has declined at a faster rate than the general population. However, the largest relative improvements have occurred prior to 1990. Emphasis on intensive blood glucose control alongside blood pressure control and statin therapy may translate into further reductions in mortality in coming years. PMID:25426948
Marks, G B; Nhung, N V; Nguyen, T A; Hoa, N B; Khoa, T H; Son, N V; Phuong, N T B; Tin, D M; Ho, J; Fox, G J
2018-03-01
The study was conducted in a randomly selected sample of persons aged 15 years living in Ca Mau Province, southern Viet Nam. To estimate the prevalence of latent tuberculous infection (LTBI) in the general adult population of this province of Viet Nam. The secondary objective was to examine age and sex differences in prevalence. A cross-sectional survey was conducted in a cluster-random sample of the population. Clusters were subcommunes. The presence of LTBI was assessed using the QuantiFERON®-TB Gold In-Tube test system. QuantiFERON tests were performed among 1319 persons aged 15 years (77.7% of those selected). The overall prevalence of positive tests was 36.8% (95%CI 33.4-40.3). The prevalence of a positive test was lower in females than in males (31.0% vs. 44.7%, OR 0.57, 95%CI 0.45-0.72, P < 0.0001). The prevalence of positive tests increased with increasing age quintile (P < 0.0001). More than one third of the general adult population in a province in southern Viet Nam have evidence of LTBI. Although LTBI prevalence is higher in males, the sex difference is not as great as that for TB notification rates.
Bias from Wireless Substitution in Surveys of Hispanics
ERIC Educational Resources Information Center
Dutwin, David; Keeter, Scott; Kennedy, Courtney
2010-01-01
Increasingly, American households are choosing to forgo ownership of landline telephones in favor of cell phones. Presently, more than 25% of Hispanics now only own a cell phone. Concern about potential bias from noncoverage of this "cell-only" population in traditional general population RDD (random digit dial) telephone interviewing has been a…
Stinchcombe, Adam R; Peskin, Charles S; Tranchina, Daniel
2012-06-01
We present a generalization of a population density approach for modeling and analysis of stochastic gene expression. In the model, the gene of interest fluctuates stochastically between an inactive state, in which transcription cannot occur, and an active state, in which discrete transcription events occur; and the individual mRNA molecules are degraded stochastically in an independent manner. This sort of model in simplest form with exponential dwell times has been used to explain experimental estimates of the discrete distribution of random mRNA copy number. In our generalization, the random dwell times in the inactive and active states, T_{0} and T_{1}, respectively, are independent random variables drawn from any specified distributions. Consequently, the probability per unit time of switching out of a state depends on the time since entering that state. Our method exploits a connection between the fully discrete random process and a related continuous process. We present numerical methods for computing steady-state mRNA distributions and an analytical derivation of the mRNA autocovariance function. We find that empirical estimates of the steady-state mRNA probability mass function from Monte Carlo simulations of laboratory data do not allow one to distinguish between underlying models with exponential and nonexponential dwell times in some relevant parameter regimes. However, in these parameter regimes and where the autocovariance function has negative lobes, the autocovariance function disambiguates the two types of models. Our results strongly suggest that temporal data beyond the autocovariance function is required in general to characterize gene switching.
Hierarchical model analysis of the Atlantic Flyway Breeding Waterfowl Survey
Sauer, John R.; Zimmerman, Guthrie S.; Klimstra, Jon D.; Link, William A.
2014-01-01
We used log-linear hierarchical models to analyze data from the Atlantic Flyway Breeding Waterfowl Survey. The survey has been conducted by state biologists each year since 1989 in the northeastern United States from Virginia north to New Hampshire and Vermont. Although yearly population estimates from the survey are used by the United States Fish and Wildlife Service for estimating regional waterfowl population status for mallards (Anas platyrhynchos), black ducks (Anas rubripes), wood ducks (Aix sponsa), and Canada geese (Branta canadensis), they are not routinely adjusted to control for time of day effects and other survey design issues. The hierarchical model analysis permits estimation of year effects and population change while accommodating the repeated sampling of plots and controlling for time of day effects in counting. We compared population estimates from the current stratified random sample analysis to population estimates from hierarchical models with alternative model structures that describe year to year changes as random year effects, a trend with random year effects, or year effects modeled as 1-year differences. Patterns of population change from the hierarchical model results generally were similar to the patterns described by stratified random sample estimates, but significant visibility differences occurred between twilight to midday counts in all species. Controlling for the effects of time of day resulted in larger population estimates for all species in the hierarchical model analysis relative to the stratified random sample analysis. The hierarchical models also provided a convenient means of estimating population trend as derived statistics from the analysis. We detected significant declines in mallard and American black ducks and significant increases in wood ducks and Canada geese, a trend that had not been significant for 3 of these 4 species in the prior analysis. We recommend using hierarchical models for analysis of the Atlantic Flyway Breeding Waterfowl Survey.
Prevalence of rosacea in the general population of Germany and Russia - The RISE study.
Tan, J; Schöfer, H; Araviiskaia, E; Audibert, F; Kerrouche, N; Berg, M
2016-03-01
There is an unmet need for general population-based epidemiological data on rosacea based on contemporary diagnostic criteria and validated population survey methodology. To evaluate the prevalence of rosacea in the general population of Germany and Russia. General population screening was conducted in 9-10 cities per country to ensure adequate geographic representation. In Part I of this two-phase study, screening of a representative sample of the general population (every fifth person or every fifth door using a fixed-step procedure on a random route sample) was expedited with use of a questionnaire and algorithm based on current diagnostic criteria for rosacea. Of the subjects that screened positive in the initial phase, a randomly selected sample (every third subject) t`hen underwent diagnostic confirmation by a dermatologist in Part II. A total of 3052 and 3013 subjects (aged 18-65 years) were screened in Germany and Russia respectively. Rosacea prevalence was 12.3% [95%CI, 10.2-14.4] in Germany and 5.0% [95%CI, 2.8-7.2] in Russia. The profile of subjects with rosacea (75% women; mean age of 40 years; mainly skin phototype II or III, majority of subjects with sensitive facial skin) and subtype distribution were similar. Overall, 18% of subjects diagnosed with rosacea were aged 18-30 years. Over 80% were not previously diagnosed. Within the previous year, 47.5% of subjects had received no rosacea care and 23.7% had received topical and/or systemic drugs. Over one-third (35% Germany, 43% Russia) of rosacea subjects reported a moderate to severe adverse impact on quality of life. Rosacea is highly prevalent in Germany (12.3%) and Russia (5.0%). The demographic profile of rosacea subjects was similar between countries and the majority were previously undiagnosed. © 2016 The Authors. Journal of the European Academy of Dermatology and Venereology published by John Wiley & Sons Ltd on behalf of European Academy of Dermatology and Venereology.
Crime Victimization in Adults With Severe Mental Illness
Teplin, Linda A.; McClelland, Gary M.; Abram, Karen M.; Weiner, Dana A.
2006-01-01
Context Since deinstitutionalization, most persons with severe mental illness (SMI) now live in the community, where they are at great risk for crime victimization. Objectives To determine the prevalence and incidence of crime victimization among persons with SMI by sex, race/ethnicity, and age, and to compare rates with general population data (the National Crime Victimization Survey), controlling for income and demographic differences between the samples. Design Epidemiologic study of persons in treatment. Independent master’s-level clinical research interviewers administered the National Crime Victimization Survey to randomly selected patients sampled from 16 randomly selected mental health agencies. Setting Sixteen agencies providing outpatient, day, and residential treatment to persons with SMI in Chicago, Ill. Participants Randomly selected, stratified sample of 936 patients aged 18 or older (483 men, 453 women) who were African American (n = 329), non-Hispanic white (n = 321), Hispanic (n = 270), or other race/ethnicity (n = 22). The comparison group comprised 32449 participants in the National Crime Victimization Survey. Main Outcome Measure National Crime Victimization Survey, developed by the Bureau of Justice Statistics. Results More than one quarter of persons with SMI had been victims of a violent crime in the past year, a rate more than 11 times higher than the general population rates even after controlling for demographic differences between the 2 samples (P<.001). The annual incidence of violent crime in the SMI sample (168.2 incidents per 1000 persons) is more than 4 times higher than the general population rates (39.9 incidents per 1000 persons) (P<.001). Depending on the type of violent crime (rape/sexual assault, robbery, assault, and their subcategories), prevalence was 6 to 23 times greater among persons with SMI than among the general population. Conclusions Crime victimization is a major public health problem among persons with SMI who are treated in the community. We recommend directions for future research, propose modifications in public policy, and suggest how the mental health system can respond to reduce victimization and its consequences. PMID:16061769
Teplin, Linda A; McClelland, Gary M; Abram, Karen M; Weiner, Dana A
2005-08-01
Since deinstitutionalization, most persons with severe mental illness (SMI) now live in the community, where they are at great risk for crime victimization. To determine the prevalence and incidence of crime victimization among persons with SMI by sex, race/ethnicity, and age, and to compare rates with general population data (the National Crime Victimization Survey), controlling for income and demographic differences between the samples. Epidemiologic study of persons in treatment. Independent master's-level clinical research interviewers administered the National Crime Victimization Survey to randomly selected patients sampled from 16 randomly selected mental health agencies. Sixteen agencies providing outpatient, day, and residential treatment to persons with SMI in Chicago, Ill. Randomly selected, stratified sample of 936 patients aged 18 or older (483 men, 453 women) who were African American (n = 329), non-Hispanic white (n = 321), Hispanic (n = 270), or other race/ethnicity (n = 22). The comparison group comprised 32 449 participants in the National Crime Victimization Survey. National Crime Victimization Survey, developed by the Bureau of Justice Statistics. More than one quarter of persons with SMI had been victims of a violent crime in the past year, a rate more than 11 times higher than the general population rates even after controlling for demographic differences between the 2 samples (P<.001). The annual incidence of violent crime in the SMI sample (168.2 incidents per 1000 persons) is more than 4 times higher than the general population rates (39.9 incidents per 1000 persons) (P<.001). Depending on the type of violent crime (rape/sexual assault, robbery, assault, and their subcategories), prevalence was 6 to 23 times greater among persons with SMI than among the general population. Crime victimization is a major public health problem among persons with SMI who are treated in the community. We recommend directions for future research, propose modifications in public policy, and suggest how the mental health system can respond to reduce victimization and its consequences.
Abdalla, Safa; Kelleher, Cecily C; Quirke, Brigid; Daly, Leslie
2013-01-01
Objectives To assess recent disparities in fatal and non-fatal injury between travellers and the general population in Ireland. Design A cross-sectional population-based comparative study. Setting Republic of Ireland. Participants Population census and retrospective mortality data were collected from 7042 traveller families, travellers being those identified by themselves and others as members of the traveller community. Retrospective injury incidence was estimated from a survey of a random sample of travellers in private households, aged 15 years or over (702 men and 961 women). Comparable general population data were obtained from official statistical reports, while retrospective incidence was estimated from the Survey of Lifestyle, Attitude and Nutrition 2002, a random sample of 5992 adults in private households aged 18 years or over. Outcome measures Potential Years of Life Lost (PYLL), Standardised Mortality Ratios (SMR), Standardised Incidence Ratios (SIR) and Case Fatality Ratios (CFR). Results Injury accounted for 36% of PYLL among travellers, compared with 13% in the general population. travellers were more likely to die of unintentional injury than the general population (SMR=454 (95% CI 279 to 690) in men and 460 (95% CI 177 to 905) in women), with a similar pattern for intentional injury (SMR=637 (95% CI 367 to 993) in men and 464 (95% CI 107 to 1204 in women). They had a lower incidence of unintentional injury but those aged 65 years or over were about twice as likely to report an injury. Travellers had a higher incidence of intentional injuries (SIR=181 (95% CI 116 to 269) in men and 268 (95% CI 187 to 373) in women). Injury CFR were consistently higher among travellers. Conclusions Irish travellers continue to bear a disproportionate burden of injury, which calls for scaling up injury prevention efforts in this group. Prevention and further research should focus on suicide, alcohol misuse and elderly injury among Irish travellers. PMID:23358563
Nonlinear Relaxation in Population Dynamics
NASA Astrophysics Data System (ADS)
Cirone, Markus A.; de Pasquale, Ferdinando; Spagnolo, Bernardo
We analyze the nonlinear relaxation of a complex ecosystem composed of many interacting species. The ecological system is described by generalized Lotka-Volterra equations with a multiplicative noise. The transient dynamics is studied in the framework of the mean field theory and with random interaction between the species. We focus on the statistical properties of the asymptotic behaviour of the time integral of the ith population and on the distribution of the population and of the local field.
Smoking profile among the gay and lesbian community in Ireland.
Kabir, Z; Keogan, S; Clarke, V; Currie, L M; Clancy, L
2010-09-01
We hypothesized that smoking rates among the Gay and Lesbian Community (GLC) in Ireland are not significantly different from the general Irish population. A convenience sampling of self-identified GLC was recruited using electronic (n = 700) and print (n = 500) media procedures in response to survey call advertisements (December 2006-March 2007). In all, 1,113 had complete smoking data and were analyzed. Data on a random sample of 4,000 individuals, using the Irish Office of Tobacco Control monthly telephone survey, were analyzed for the same period. Adjusted smoking rates in GLC were 26 and 24.6% in the general Irish population (P = 0.99), while "heavy" (> or =20 cigarettes/day) smoking prevalence was 44.1 and 36.6%, respectively (P = 0.02). Upper SES GLCs are "heavy" smokers compared with general population of similar SES group (P = 0.01). When considering two different sampling methodologies, this study suggests that smoking rates among the GLC in Ireland are not significantly different from the general Irish population.
Hobbs, F D R; Davis, R C; Roalfe, A K; Hare, R; Davies, M K
2004-08-01
To determine the performance of a new NT-proBNP assay in comparison with brain natriuretic peptide (BNP) in identifying left ventricular systolic dysfunction (LVSD) in randomly selected community populations. Blood samples were taken prospectively in the community from 591 randomly sampled individuals over the age of 45 years, stratified for age and socioeconomic status and divided into four cohorts (general population; clinically diagnosed heart failure; patients on diuretics; and patients deemed at high risk of heart failure). Definite heart failure (left ventricular ejection fraction (LVEF) < 40%) was identified in 33 people. Samples were handled as though in routine clinical practice. The laboratories undertaking the assays were blinded. Using NT-proBNP to diagnose LVEF < 40% in the general population, a level of > 40 pmol/l had 80% sensitivity, 73% specificity, 5% positive predictive value (PPV), 100% negative predictive value (NPV), and an area under the receiver-operator characteristic curve (AUC) of 76% (95% confidence interval (CI) 46% to 100%). For BNP to diagnose LVSD, a cut off level of > 33 pmol/l had 80% sensitivity, 88% specificity, 10% PPV, 100% NPV, and AUC of 88% (95% CI 75% to 100%). Similar NPVs were found for patients randomly screened from the three other populations. Both NT-proBNP and BNP have value in diagnosing LVSD in a community setting, with similar sensitivities and specificities. Using a high cut off for positivity will confirm the diagnosis of LVSD but will miss cases. At lower cut off values, positive results will require cardiac imaging to confirm LVSD.
Alcañiz, Manuela; Guillén, Montserrat; Santolino, Miguel; Sánchez-Moscona, Daniel; Llatje, Oscar; Ramon, Lluís
2014-04-01
Sobriety checkpoints are not usually randomly located by traffic authorities. As such, information provided by non-random alcohol tests cannot be used to infer the characteristics of the general driving population. In this paper a case study is presented in which the prevalence of alcohol-impaired driving is estimated for the general population of drivers. A stratified probabilistic sample was designed to represent vehicles circulating in non-urban areas of Catalonia (Spain), a region characterized by its complex transportation network and dense traffic around the metropolis of Barcelona. Random breath alcohol concentration tests were performed during spring 2012 on 7596 drivers. The estimated prevalence of alcohol-impaired drivers was 1.29%, which is roughly a third of the rate obtained in non-random tests. Higher rates were found on weekends (1.90% on Saturdays and 4.29% on Sundays) and especially at night. The rate is higher for men (1.45%) than for women (0.64%) and it shows an increasing pattern with age. In vehicles with two occupants, the proportion of alcohol-impaired drivers is estimated at 2.62%, but when the driver was alone the rate drops to 0.84%, which might reflect the socialization of drinking habits. The results are compared with outcomes in previous surveys, showing a decreasing trend in the prevalence of alcohol-impaired drivers over time. Copyright © 2014 Elsevier Ltd. All rights reserved.
Ollivier, Y; Saraux, A; Le Goff, P
2004-01-01
To evaluate the influence of lifestyle factors on the prevalence of rheumatoid arthritis (RA) by comparing Roman Catholic nuns and the general female population. RA prevalence in the general population was evaluated using a standardized telephone survey in 1857 homes taken at random. Individuals who reported an inflammatory joint disease were contacted by a rheumatologist of our unit, missing data were collected from the general practitioner or rheumatologist with the patient's permission, and if necessary a physical examination was done by a rheumatologist. The 9 largest Roman Catholic nun communities in Brittany were screened using the same standardized questionnaire administered face-to-face; nuns who reported an inflammatory joint disease were interviewed and examined by rheumatologists. In both populations, RA was diagnosed when (1) the rheumatologist of our unit who interviewed the patient considered the RA classification criteria positive and (2) the rheumatologist who examined the patient gave a diagnosis of RA independently from RA classification criteria. Data were available for 1706 adult females in the general population and 721 nuns. Of the 20 nuns who reported RA or polyarthritis, 11 received a diagnosis of RA (prevalence 1.52%). The prevalences adjustedfor the French population after 40 years were 1.66% (95% confidence interval, 0.84-2.44) and 1.33 (0.27-2.40) among the nuns and the general female population, respectively. Although our nun population was too small for definite conclusions, we found no evidence of a difference in RA prevalence among nuns and the general female population in Brittany.
Alfonso, Jose Hernan; Thyssen, Jacob P; Tynes, Tore; Mehlum, Ingrid Sivesind; Johannessen, Håkon A
2015-11-01
Prospective studies on occupational dermatoses in the general working population are sparse. This study investigated prospectively the impact of self-reported occupational exposure to chemicals and physical factors on the risk of skin problems. The cohort comprised respondents drawn randomly from the general population in Norway, who were registered employed in 2006 and 2009 (n = 6,745). Indoor dry air (odds ratio (OR) 1.3; 95% confidence interval (95% CI) 1.1-1.6) was a significant baseline predictor of skin problems at follow-up, whereas exposure to cleaning products (OR 1.7; 95% CI 1.2-2.5), water (OR 1.4; 95% CI 1.1-1.9) and indoor dry air (OR 1.6; 95% CI 1.1-2.1) at both measurement time-points was significantly associated with skin problems. The population risk attributable to these factors was 16%. This study quantified the contribution of occupational exposure factors to skin problems in the general working population of Norway.
Harry T. Valentine; David L. R. Affleck; Timothy G. Gregoire
2009-01-01
Systematic sampling is easy, efficient, and widely used, though it is not generally recognized that a systematic sample may be drawn from the population of interest with or without restrictions on randomization. The restrictions or the lack of them determine which estimators are unbiased, when using the sampling design as the basis for inference. We describe the...
Universal self-similarity of propagating populations
NASA Astrophysics Data System (ADS)
Eliazar, Iddo; Klafter, Joseph
2010-07-01
This paper explores the universal self-similarity of propagating populations. The following general propagation model is considered: particles are randomly emitted from the origin of a d -dimensional Euclidean space and propagate randomly and independently of each other in space; all particles share a statistically common—yet arbitrary—motion pattern; each particle has its own random propagation parameters—emission epoch, motion frequency, and motion amplitude. The universally self-similar statistics of the particles’ displacements and first passage times (FPTs) are analyzed: statistics which are invariant with respect to the details of the displacement and FPT measurements and with respect to the particles’ underlying motion pattern. Analysis concludes that the universally self-similar statistics are governed by Poisson processes with power-law intensities and by the Fréchet and Weibull extreme-value laws.
Universal self-similarity of propagating populations.
Eliazar, Iddo; Klafter, Joseph
2010-07-01
This paper explores the universal self-similarity of propagating populations. The following general propagation model is considered: particles are randomly emitted from the origin of a d-dimensional Euclidean space and propagate randomly and independently of each other in space; all particles share a statistically common--yet arbitrary--motion pattern; each particle has its own random propagation parameters--emission epoch, motion frequency, and motion amplitude. The universally self-similar statistics of the particles' displacements and first passage times (FPTs) are analyzed: statistics which are invariant with respect to the details of the displacement and FPT measurements and with respect to the particles' underlying motion pattern. Analysis concludes that the universally self-similar statistics are governed by Poisson processes with power-law intensities and by the Fréchet and Weibull extreme-value laws.
Coevolutionary dynamics in large, but finite populations
NASA Astrophysics Data System (ADS)
Traulsen, Arne; Claussen, Jens Christian; Hauert, Christoph
2006-07-01
Coevolving and competing species or game-theoretic strategies exhibit rich and complex dynamics for which a general theoretical framework based on finite populations is still lacking. Recently, an explicit mean-field description in the form of a Fokker-Planck equation was derived for frequency-dependent selection with two strategies in finite populations based on microscopic processes [A. Traulsen, J. C. Claussen, and C. Hauert, Phys. Rev. Lett. 95, 238701 (2005)]. Here we generalize this approach in a twofold way: First, we extend the framework to an arbitrary number of strategies and second, we allow for mutations in the evolutionary process. The deterministic limit of infinite population size of the frequency-dependent Moran process yields the adjusted replicator-mutator equation, which describes the combined effect of selection and mutation. For finite populations, we provide an extension taking random drift into account. In the limit of neutral selection, i.e., whenever the process is determined by random drift and mutations, the stationary strategy distribution is derived. This distribution forms the background for the coevolutionary process. In particular, a critical mutation rate uc is obtained separating two scenarios: above uc the population predominantly consists of a mixture of strategies whereas below uc the population tends to be in homogeneous states. For one of the fundamental problems in evolutionary biology, the evolution of cooperation under Darwinian selection, we demonstrate that the analytical framework provides excellent approximations to individual based simulations even for rather small population sizes. This approach complements simulation results and provides a deeper, systematic understanding of coevolutionary dynamics.
The Dynamical Classification of Centaurs which Evolve into Comets
NASA Astrophysics Data System (ADS)
Wood, Jeremy R.; Horner, Jonathan; Hinse, Tobias; Marsden, Stephen; Swinburne University of Technology
2016-10-01
Centaurs are small Solar system bodies with semi-major axes between Jupiter and Neptune and perihelia beyond Jupiter. Centaurs can be further subclassified into two dynamical categories - random walk and resonance hopping. Random walk Centaurs have mean square semi-major axes (< a2 >) which vary in time according to a generalized diffusion equation where < a2 > ~t2H. H is the Hurst exponent with 0 < H < 1, and t is time. The behavior of < a2 > for resonance hopping Centaurs is not well described by generalized diffusion.The aim of this study is to determine which dynamical type of Centaur is most likely to evolve into each class of comet. 31,722 fictional massless test particles were integrated for 3 Myr in the 6-body problem (Sun, Jovian planets, test particle). Initially each test particle was a member of one of four groups. The semi-major axes of all test particles in a group were clustered within 0.27 au from a first order, interior Mean Motion resonance of Neptune. The resonances were centered at 18.94 au, 22.95 au, 24.82 au and 28.37 au.If the perihelion of a test particle reached < 4 au then the test particle was considered to be a comet and classified as either a random walk or resonance hopping Centaur. The results showed that over 4,000 test particles evolved into comets within 3 Myr. 59% of these test particles were random walk and 41% were resonance hopping. The behavior of the semi-major axis in time was usually well described by generalized diffusion for random walk Centaurs (ravg = 0.98) and poorly described for resonance hopping Centaurs (ravg = 0.52). The average Hurst exponent was 0.48 for random walk Centaurs and 0.20 for resonance hopping Centaurs. Random walk Centaurs were more likely to evolve into short period comets while resonance hopping Centaurs were more likely to evolve into long period comets. For each initial cluster, resonance hopping Centaurs took longer to evolve into comets than random walk Centaurs. Overall the population of random walk Centaurs averaged 143 kyr to evolve into comets, and the population of resonance hopping Centaurs averaged 164 kyr.
Generalizing Evidence From Randomized Clinical Trials to Target Populations
Cole, Stephen R.; Stuart, Elizabeth A.
2010-01-01
Properly planned and conducted randomized clinical trials remain susceptible to a lack of external validity. The authors illustrate a model-based method to standardize observed trial results to a specified target population using a seminal human immunodeficiency virus (HIV) treatment trial, and they provide Monte Carlo simulation evidence supporting the method. The example trial enrolled 1,156 HIV-infected adult men and women in the United States in 1996, randomly assigned 577 to a highly active antiretroviral therapy and 579 to a largely ineffective combination therapy, and followed participants for 52 weeks. The target population was US people infected with HIV in 2006, as estimated by the Centers for Disease Control and Prevention. Results from the trial apply, albeit muted by 12%, to the target population, under the assumption that the authors have measured and correctly modeled the determinants of selection that reflect heterogeneity in the treatment effect. In simulations with a heterogeneous treatment effect, a conventional intent-to-treat estimate was biased with poor confidence limit coverage, but the proposed estimate was largely unbiased with appropriate confidence limit coverage. The proposed method standardizes observed trial results to a specified target population and thereby provides information regarding the generalizability of trial results. PMID:20547574
Townsend, T R; Shapiro, M; Rosner, B; Kass, E H
1979-06-01
The patterns of use of antimicrobial drugs in a random sample of general hosptials in Pennsylvania were studied. The sample was tested for validity, and all deaths and discharges were analyzed for 10 random days drawn across the year spanning July 1973 to June 1974. Methods were developed for abstracting the hospital records and for determining the reproducibility of the findings of the physician and nonphysician chart reviewers. More than 99% of the requested charts were available. In the 5,288 charts reviewed, most of the required data were readily available. The study population was 84% white and 58% female; most patients were in hospitals that had more than 300 beds and that were located in towns with populations of greater than 10,000. In 41% of the 2,070 antimicrobial courses administered to almost 30% of the patients, an explicit clinical statement of why the drug was being given could be found in the chart. The information for review was found in clinical charts, but in half of the charts, the information required was not on face sheets and discharge summaries.
ERIC Educational Resources Information Center
Walters, Karina L.; LaMarr, June; Levy, Rona L.; Pearson, Cynthia; Maresca, Teresa; Mohammed, Selina A.; Simoni, Jane M.; Evans-Campbell, Teresa; Fredriksen-Goldsen, Karen; Fryberg, Sheryl; Jobe, Jared B.
2012-01-01
American Indian and Alaska Native (AIAN) populations are disproportionately at risk for cardiovascular disease (CVD), diabetes, and obesity, compared with the general US population. This article describes the h[schwa]li?dx[superscript w]/Healthy Hearts Across Generations project, an AIAN-run, tribally based randomized controlled trial (January…
Nilsson, Annika; Carlsson, Marianne; Lindqvist, Ragny; Kristofferzon, Marja-Leena
2017-07-01
The aim was to compare coping strategies and quality of life (QoL) in patients with chronic heart failure (CHF) with such strategies and QOL in persons from two general Swedish populations and to investigate relationships between personal characteristics and coping strategies. A cross-sectional, comparative and correlational design was used to examine data from three sources. The patient group ( n = 124), defined using ICD-10, was selected consecutively from two hospitals in central Sweden. The population group ( n = 515) consisted of persons drawn randomly from the Swedish population. Data were collected with questionnaires in 2011; regarding QoL, Swedish population reference data from 1994 were used. Overall, women used more coping strategies than men did. Compared with the general population data from SF-36, patients with CHF rated lower QoL. In the regression models, perceived low "efficiency in managing psychological aspects of daily life" increased use of coping. Other personal characteristics related to increased use of coping strategies were higher education, lower age and unsatisfactory economic situation.
Generalizing the Network Scale-Up Method: A New Estimator for the Size of Hidden Populations*
Feehan, Dennis M.; Salganik, Matthew J.
2018-01-01
The network scale-up method enables researchers to estimate the size of hidden populations, such as drug injectors and sex workers, using sampled social network data. The basic scale-up estimator offers advantages over other size estimation techniques, but it depends on problematic modeling assumptions. We propose a new generalized scale-up estimator that can be used in settings with non-random social mixing and imperfect awareness about membership in the hidden population. Further, the new estimator can be used when data are collected via complex sample designs and from incomplete sampling frames. However, the generalized scale-up estimator also requires data from two samples: one from the frame population and one from the hidden population. In some situations these data from the hidden population can be collected by adding a small number of questions to already planned studies. For other situations, we develop interpretable adjustment factors that can be applied to the basic scale-up estimator. We conclude with practical recommendations for the design and analysis of future studies. PMID:29375167
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dong, J. J.; Skinner, B.; Breecher, N.
Spatial patterning can be crucially important for understanding the behavior of interacting populations. Here we investigate a simple model of parasite and host populations in which parasites are random walkers that must come into contact with a host in order to reproduce. We focus on the spatial arrangement of parasites around a single host, and we derive using analytics and numerical simulations the necessary conditions placed on the parasite fecundity and lifetime for the populations long-term survival. We also show that the parasite population can be pushed to extinction by a large drift velocity, but, counterintuitively, a small drift velocitymore » generally increases the parasite population.« less
Prevalence of atrial fibrillation in Spain. OFRECE study results.
Gómez-Doblas, Juan José; Muñiz, Javier; Martin, Joaquín J Alonso; Rodríguez-Roca, Gustavo; Lobos, José Maria; Awamleh, Paula; Permanyer-Miralda, Gaietá; Chorro, Francisco Javier; Anguita, Manuel; Roig, Eulalia
2014-04-01
Atrial fibrillation is associated with substantial morbidity and mortality and both its incidence and prevalence are high. Nevertheless, comprehensive data on this condition in Spain are lacking. The aim of this study was to estimate the prevalence of atrial fibrillation in Spain. A cross-sectional study was conducted in the general Spanish population older than 40 years. Two-stage random sampling was used, in which first-stage units were primary care physicians randomly selected in every Spanish province and second-stage units were 20 randomly selected persons drawn from each participating physician's assigned population. The reported prevalence was standardized for the age and sex distribution of the Spanish population. The electrocardiogram recordings were read centrally. Overall, 8343 individuals were evaluated. The mean age was 59.2 years (95% confidence interval, 58.6-59.8 years), and 52.4% of the participants were female. The overall age-adjusted prevalence of atrial fibrillation was 4.4% (95% confidence interval, 3.8-5.1). Prevalence was similar in both sexes, men 4.4% (3.6-5.2) and women 4.5% (3.6-5.3), rising with increasing age older than 60 years. In patients older than 80 years, the prevalence was 17.7% (14.1-21.3). In 10% of patients an unknown atrial fibrillation was diagnosed. The prevalence of atrial fibrillation in the general Spanish population older than 40 years is high, at 4.4%. The prevalence is similar in both sexes and rises steeply above 60 years of age. It is estimated that there are over 1 million patients with atrial fibrillation in the Spanish population, of whom over 90,000 are undiagnosed. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.
Person mobility in the design and analysis of cluster-randomized cohort prevention trials.
Vuchinich, Sam; Flay, Brian R; Aber, Lawrence; Bickman, Leonard
2012-06-01
Person mobility is an inescapable fact of life for most cluster-randomized (e.g., schools, hospitals, clinic, cities, state) cohort prevention trials. Mobility rates are an important substantive consideration in estimating the effects of an intervention. In cluster-randomized trials, mobility rates are often correlated with ethnicity, poverty and other variables associated with disparity. This raises the possibility that estimated intervention effects may generalize to only the least mobile segments of a population and, thus, create a threat to external validity. Such mobility can also create threats to the internal validity of conclusions from randomized trials. Researchers must decide how to deal with persons who leave study clusters during a trial (dropouts), persons and clusters that do not comply with an assigned intervention, and persons who enter clusters during a trial (late entrants), in addition to the persons who remain for the duration of a trial (stayers). Statistical techniques alone cannot solve the key issues of internal and external validity raised by the phenomenon of person mobility. This commentary presents a systematic, Campbellian-type analysis of person mobility in cluster-randomized cohort prevention trials. It describes four approaches for dealing with dropouts, late entrants and stayers with respect to data collection, analysis and generalizability. The questions at issue are: 1) From whom should data be collected at each wave of data collection? 2) Which cases should be included in the analyses of an intervention effect? and 3) To what populations can trial results be generalized? The conclusions lead to recommendations for the design and analysis of future cluster-randomized cohort prevention trials.
Stockburger, Martin; Boveda, Serge; Moreno, Javier; Da Costa, Antoine; Hatala, Robert; Brachmann, Johannes; Butter, Christian; Garcia Seara, Javier; Rolando, Mara; Defaye, Pascal
2015-01-01
Aim Right ventricular pacing (VP) has been hypothesized to increase the risk in heart failure (HF) and atrial fibrillation (AF). The ANSWER study evaluated, whether an AAI-DDD changeover mode to minimize VP (SafeR) improves outcome compared with DDD in a general dual-chamber pacemaker population. Methods and results ANSWER was a randomized controlled multicentre trial assessing SafeR vs. standard DDD in sinus node disease (SND) or AV block (AVB) patients. After a 1-month run-in period, they were randomized (1 : 1) and followed for 3 years. Pre-specified co-primary end-points were VP and the composite of hospitalization for HF, AF, or cardioversion. Pre-specified secondary end-points were cardiac death or HF hospitalizations and cardiovascular hospitalizations. ANSWER enrolled 650 patients (52.0% SND, 48% AVB) at 43 European centres and randomized in SafeR (n = 314) or DDD (n = 318). The SafeR mode showed a significant decrease in VP compared with DDD (11.5 vs. 93.6%, P < 0.0001 at 3 years). Deaths and syncope did not differ between randomization arms. No significant difference between groups [HR = 0.78; 95% CI (0.48–1.25); P = 0.30] was found in the time to event of the co-primary composite of hospitalization for HF, AF, or cardioversion, nor in the individual components. SafeR showed a 51% risk reduction (RR) in experiencing cardiac death or HF hospitalization [HR = 0.49; 95% CI (0.27–0.90); P = 0.02] and 30% RR in experiencing cardiovascular hospitalizations [HR = 0.70; 95% CI (0.49–1.00); P = 0.05]. Conclusion SafeR safely and significantly reduced VP in a general pacemaker population though had no effect on hospitalization for HF, AF, or cardioversion, when compared with DDD. PMID:25179761
Tanash, Hanan A; Ekström, Magnus; Rönmark, Eva; Lindberg, Anne; Piitulainen, Eeva
2017-09-01
Knowledge about the natural history of severe alpha 1-antitrypsin (AAT) deficiency (PiZZ) is limited. Our aim was to compare the survival of PiZZ individuals with randomly selected controls from the Swedish general population.The PiZZ subjects (n=1585) were selected from the Swedish National AATD Register. The controls (n=5999) were randomly selected from the Swedish population register. Smoking habits were known for all subjects.Median follow-up times for the PiZZ subjects (731 never-smokers) and controls (3179 never-smokers) were 12 and 17 years, respectively (p<0.001). During follow-up, 473 PiZZ subjects (30%), and 747 controls (12%) died. The PiZZ subjects had a significantly shorter survival time than the controls, p<0.001. After adjustment for gender, age, smoking habits and presence of respiratory symptoms, the risk of death was still significantly higher for the PiZZ individuals than for the controls, hazard ratio (HR) 3.2 (95% CI 2.8-3.6; p<0.001). By contrast, the risk of death was not increased in never-smoking PiZZ individuals identified by screening, compared to never-smoking controls, HR 1.2 (95% CI 0.6-2.2).The never-smoking PiZZ individuals identified by screening had a similar life expectancy to the never-smokers in the Swedish general population. Early diagnosis of AAT deficiency is of utmost importance. Copyright ©ERS 2017.
Vrdoljak, Davorka; Marković, Biserka Bergman; Puljak, Livia; Lalić, Dragica Ivezić; Kranjčević, Ksenija; Vučak, Jasna
2014-01-01
The purpose of the study was to compare the effectiveness of programmed and intensified intervention on lifestyle changes, including physical activity, cigarette smoking, alcohol consumption and diet, in patients aged ≥ 65 with the usual care of general practitioners (GP). In this multicenter randomized controlled trial, 738 patients aged ≥ 65 were randomly assigned to receive intensified intervention (N = 371) or usual care (N = 367) of a GP for lifestyle changes, with 18-month follow-up. The main outcome measures were physical activity, smoking, alcohol consumption and diet. The study was conducted in 59 general practices in Croatia between May 2008 and May 2010. The patients' mean age was 72.3 ± 5.2 years. Significant diet correction was achieved after 18-month follow-up in the intervention group, comparing to controls. More patients followed strictly Mediterranean diet and consumed healthy foods more frequently. There was no significant difference between the groups in physical activity, tobacco smoking and alcohol consumption or diet after the intervention. In conclusion, an 18-month intensified GP's intervention had limited effect on lifestyle habits. GP intervention managed to change dietary habits in elderly population, which is encouraging since elderly population is very resistant regarding lifestyle habit changes. Clinical trial registration number. ISRCTN31857696. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
ERIC Educational Resources Information Center
Scior, Katrina; Connolly, Theresa; Williams, Janice
2013-01-01
Labels are firmly rejected by the disability rights movement, yet the complex effects of labeling on lay beliefs are poorly understood. This study examined the effects of labeling on the general public's reactions to people with intellectual disabilities. A sample of 1,233 adult members of the UK general population were randomly presented with…
Spatial structures in a simple model of population dynamics for parasite-host interactions
NASA Astrophysics Data System (ADS)
Dong, J. J.; Skinner, B.; Breecher, N.; Schmittmann, B.; Zia, R. K. P.
2015-08-01
Spatial patterning can be crucially important for understanding the behavior of interacting populations. Here we investigate a simple model of parasite and host populations in which parasites are random walkers that must come into contact with a host in order to reproduce. We focus on the spatial arrangement of parasites around a single host, and we derive using analytics and numerical simulations the necessary conditions placed on the parasite fecundity and lifetime for the population's long-term survival. We also show that the parasite population can be pushed to extinction by a large drift velocity, but, counterintuitively, a small drift velocity generally increases the parasite population.
Randomized clinical trials and observational studies in the assessment of drug safety.
Sawchik, J; Hamdani, J; Vanhaeverbeek, M
2018-05-01
Randomized clinical trials are considered as the preferred design to assess the potential causal relationships between drugs or other medical interventions and intended effects. For this reason, randomized clinical trials are generally the basis of development programs in the life cycle of drugs and the cornerstone of evidence-based medicine. Instead, randomized clinical trials are not the design of choice for the detection and assessment of rare, delayed and/or unexpected effects related to drug safety. Moreover, the highly homogeneous populations resulting from restrictive eligibility criteria make randomized clinical trials inappropriate to describe comprehensively the safety profile of drugs. In that context, observational studies have a key added value when evaluating the benefit-risk balance of the drugs. However, observational studies are more prone to bias than randomized clinical trials and they have to be designed, conducted and reported judiciously. In this article, we discuss the strengths and limitations of randomized clinical trials and of observational studies, more particularly regarding their contribution to the knowledge of medicines' safety profile. In addition, we present general recommendations for the sensible use of observational data. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
NASA Technical Reports Server (NTRS)
Kastner, S. O.; Bhatia, A. K.
1980-01-01
A generalized method for obtaining individual level population ratios is used to obtain relative intensities of extreme ultraviolet Fe XV emission lines in the range 284-500 A, which are density dependent for electron densities in the tokamak regime or higher. Four lines in particular are found to attain quite high intensities in the high-density limit. The same calculation provides inelastic contributions to linewidths. The method connects level populations and level widths through total probabilities t(ij), related to 'taboo' probabilities of Markov chain theory. The t(ij) are here evaluated for a real atomic system, being therefore of potential interest to random-walk theorists who have been limited to idealized systems characterized by simplified transition schemes.
NASA Astrophysics Data System (ADS)
Kastner, S. O.; Bhatia, A. K.
1980-08-01
A generalized method for obtaining individual level population ratios is used to obtain relative intensities of extreme ultraviolet Fe XV emission lines in the range 284-500 A, which are density dependent for electron densities in the tokamak regime or higher. Four lines in particular are found to attain quite high intensities in the high-density limit. The same calculation provides inelastic contributions to linewidths. The method connects level populations and level widths through total probabilities t(ij), related to 'taboo' probabilities of Markov chain theory. The t(ij) are here evaluated for a real atomic system, being therefore of potential interest to random-walk theorists who have been limited to idealized systems characterized by simplified transition schemes.
Le Quintrec, Jean-Laurent; Bussy, Caroline; Golmard, Jean-Louis; Hervé, Christian; Baulon, Alain; Piette, François
2005-03-01
Very elderly subjects (VES; aged 80 years or older) constitute a special population as they frequently present multiple diseases (polypathology). Results from trials on general adult populations therefore cannot be extrapolated to VES. We performed a census of randomized controlled trials (RCT) on VES published between 1990 and 2002, and carried out a descriptive and methodological analysis of these RCT/VES, comparing them with matched RCT on general adult populations (control RCT, RCT/C). We searched for RCT/VES in two international databases (EMBASE and MEDLINE) and then manually. RCT/C were matched to RCT/VES for disease area and year of publication. The methodological quality of each RCT was assessed with Chalmers' scale. We identified 84 RCT/VES, 63 of which were conclusive and 21, inconclusive. Subjects were institutionalized in 48 RCT, and community dwelling in 11 RCT (unspecified in 25 RCT). Efficacy was the main criterion in 75 RCT; tolerance in 9 RCT. Twenty-six RCT were published by geriatrics journals, and 58 by general medical journals. The RCT/VES covered most of the disease areas of geriatrics. The 84 RCT/VES had a mean methodological quality score of 0.578 +/- 0.157. The matched 84 RCT/C had a mean methodological quality score of 0.592 +/- 0.116 (p = .466). The methodological quality score of RCT/VES increased with the number of included subjects (p = .004) and the year of publication (p = .001). The methodological quality of RCT/VES is equivalent to that of RCT in general adult populations. Nevertheless, RCT/VES remain very scarce, and neglect certain diseases. RCT/VES and the inclusion of very elderly subjects in RCT on adults should be strongly encouraged.
Peláez-Fernández, María Angeles; Ruiz-Lázaro, Pedro Manuel; Labrador, Francisco Javier; Raich, Rosa María
2014-02-20
To validate the best cut-off point of the Eating Attitudes Test (EAT-40), Spanish version, for the screening of eating disorders (ED) in the general population. This was a transversal cross-sectional study. The EAT-40 Spanish version was administered to a representative sample of 1.543 students, age range 12 to 21 years, in the Region of Madrid. Six hundred and two participants (probable cases and a random sample of controls) were interviewed. The best diagnostic prediction was obtained with a cut-off point of 21, with sensitivity: 88.2%; specificity: 62.1%; positive predictive value: 17.7%; negative predictive value: 62.1%. Use of a cut-off point of 21 is recommended in epidemiological studies of eating disorders in the Spanish general population. Copyright © 2012 Elsevier España, S.L. All rights reserved.
Zielaskowski, Kate; White, Kirsten AM; Rodríguez, Vivian M; Robers, Erika; Guest, Dolores D; Sussman, Andrew; Talamantes, Yvonne; Schwartz, Matthew R; Greb, Jennie; Bigney, Jessica; Kaphingst, Kimberly A; Hunley, Keith; Buller, David B
2017-01-01
Background Limited translational genomic research currently exists to guide the availability, comprehension, and appropriate use of personalized genomics in diverse general population subgroups. Melanoma skin cancers are preventable, curable, common in the general population, and disproportionately increasing in Hispanics. Objective Variants in the melanocortin-1 receptor (MC1R) gene are present in approximately 50% of the population, are major factors in determining sun sensitivity, and confer a 2-to-3-fold increase in melanoma risk in the general population, even in populations with darker skin. Therefore, feedback regarding MC1R risk status may raise risk awareness and protective behavior in the general population. Methods We are conducting a randomized controlled trial examining Internet presentation of the risks and benefits of personalized genomic testing for MC1R gene variants that are associated with increased melanoma risk. We will enroll a total of 885 participants (462 participants are currently enrolled), who will be randomized 6:1 to personalized genomic testing for melanoma risk versus waiting list control. Control participants will be offered testing after outcome assessments. Participants will be balanced across self-reported Hispanic versus non-Hispanic ethnicity (n=750 in personalized genomic testing for melanoma risk arm; n=135 in control arm), and will be recruited from a general population cohort in Albuquerque, New Mexico, which is subject to year-round sun exposure. Baseline surveys will be completed in-person with study staff and follow-up measures will be completed via telephone. Results Aim 1 of the trial will examine the personal utility of personalized genomic testing for melanoma risk in terms of short-term (3-month) sun protection and skin screening behaviors, family and physician communication, and melanoma threat and control beliefs (ie, putative mediators of behavior change). We will also examine potential unintended consequences of testing among those who receive average-risk personalized genomic testing for melanoma risk findings, and examine predictors of sun protection at 3 months as the outcome. These findings will be used to develop messages for groups that receive average-risk feedback. Aim 2 will compare rates of test consideration in Hispanics versus non-Hispanics, including consideration of testing pros and cons and registration of a decision to either accept or decline testing. Aim 3 will examine personalized genomic testing for melanoma risk feedback comprehension, recall, satisfaction, and cancer-related distress in those who undergo testing, and whether these outcomes differ by ethnicity (Hispanic vs non-Hispanic), or sociocultural or demographic factors. Final outcome data collection is anticipated to be complete by October 2017, at which point data analysis will commence. Conclusions This study has important implications for personalized genomics in the context of melanoma risk, and may be broadly applicable as a model for delivery of personalized genomic feedback for other health conditions. PMID:28442450
Identification of countermeasures for the youth crash problem related to alcohol
DOT National Transportation Integrated Search
1975-01-01
Face-to-face interviews were conducted with male New York State drivers. These groups, each containing young (16-24 years) and middle aged (35-49 years) drivers were sampled as follows: 1) random sample of the general population of licensed drivers (...
Stochastic analysis of a pulse-type prey-predator model
NASA Astrophysics Data System (ADS)
Wu, Y.; Zhu, W. Q.
2008-04-01
A stochastic Lotka-Volterra model, a so-called pulse-type model, for the interaction between two species and their random natural environment is investigated. The effect of a random environment is modeled as random pulse trains in the birth rate of the prey and the death rate of the predator. The generalized cell mapping method is applied to calculate the probability distributions of the species populations at a state of statistical quasistationarity. The time evolution of the population densities is studied, and the probability of the near extinction time, from an initial state to a critical state, is obtained. The effects on the ecosystem behaviors of the prey self-competition term and of the pulse mean arrival rate are also discussed. Our results indicate that the proposed pulse-type model shows obviously distinguishable characteristics from a Gaussian-type model, and may confer a significant advantage for modeling the prey-predator system under discrete environmental fluctuations.
Stochastic analysis of a pulse-type prey-predator model.
Wu, Y; Zhu, W Q
2008-04-01
A stochastic Lotka-Volterra model, a so-called pulse-type model, for the interaction between two species and their random natural environment is investigated. The effect of a random environment is modeled as random pulse trains in the birth rate of the prey and the death rate of the predator. The generalized cell mapping method is applied to calculate the probability distributions of the species populations at a state of statistical quasistationarity. The time evolution of the population densities is studied, and the probability of the near extinction time, from an initial state to a critical state, is obtained. The effects on the ecosystem behaviors of the prey self-competition term and of the pulse mean arrival rate are also discussed. Our results indicate that the proposed pulse-type model shows obviously distinguishable characteristics from a Gaussian-type model, and may confer a significant advantage for modeling the prey-predator system under discrete environmental fluctuations.
Shin, Hae Won; Noh, Dong Young; Lee, Eun Sook; Nam, Seok Jin; Park, Byeong Woo; Ahn, Sei Hyun; Yun, Young Ho
2009-11-01
The aim was to evaluate the correlates of existential well-being (EWB) and investigate the relationship between EWB and health-related quality of life (HRQOL) according to the McGill Quality of Life Questionnaire (MQOL) in breast cancer survivors (BCS) and in the general population. BCS (N = 1,933) recruited from five large hospitals completed a mailed survey, which included the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (QLQ-C30), Quality of Life Questionnaire Breast Cancer Module (QLQ-BR23) and the MQOL. Reference data were derived from a representative sample of the Korean adult population composed of 500 women selected by a nationwide random route technique. Multiple logistic regression analysis showed that members of the general population with a lower educational status were more likely to report poor EWB. However, among BCS, correlates that were associated with poor EWB included lower monthly income, lower educational status, unemployment and comorbidities. Almost all factors listed on the HRQOL questionnaire were correlated with EWB in BCS as well as in the general population (P < 0.001). Factors listed on the QLQ-C30 that were correlated to a clinically meaningful extent with EWB in the general population included physical functioning, nausea and vomiting, and appetite loss, whereas among BCS, insomnia and distress over hair loss were meaningfully correlated with EWB. Compared with general population, BCS showed different EWB correlates and distinct associations with HRQOL findings. Our data suggest that socio-economic status and comorbidities influence on their EWB.
Increased risk of chronic liver disease in patients with bipolar disorder: A population-based study.
Hsu, Jer-Hwa; Chien, I-Chia; Lin, Ching-Heng
2016-01-01
This study aimed to investigate the prevalence and incidence of chronic liver disease in patients with bipolar disorder. We used a random sample of 766,427 subjects aged ≥18 years from the National Health Research Institute database in the year 2005. Subjects with at least one primary diagnosis of bipolar disorder in 2005 were identified. Patients with a primary or secondary diagnosis of chronic liver disease were also defined. We compared the prevalence and associated factors of chronic liver disease between patients with bipolar disorder and the general population in 2005. We also compared the incidence of chronic liver disease in patients with bipolar disorder and the general population from 2006 to 2010. The prevalence of chronic liver disease in patients with bipolar disorder (13.9%) was 2.68 times higher than that of the general population (5.8%) in 2005. The average annual incidence of chronic liver disease in patients with bipolar disorder from 2006 to 2010 was also higher than that of the general population (2.95% vs. 1.73%; risk ratio: 1.71; 95% confidence interval: 1.46-2.01). Patients with bipolar disorder had a significantly higher prevalence and incidence of chronic liver disease than those in the general population, and younger patients with bipolar disorder have a much higher prevalence and incidence than those in the general population. Male sex, second-generation antipsychotic or antidepressant use, and hyperlipidemia were associated factors for chronic liver disease in patients with bipolar disorder. Copyright © 2016 Elsevier Inc. All rights reserved.
Diepgen, T L; Ofenloch, R; Bruze, M; Cazzaniga, S; Coenraads, P J; Elsner, P; Goncalo, M; Svensson, Å; Naldi, L
2015-12-01
Contact allergy to fragrances is assessed mostly in clinical populations of patients. Studies in the general population are scarce and vary in their methodology across countries. To determine the prevalence of fragrance contact allergy in the European general population and to assess the clinical relevance of positive patch test reactions to different fragrances. In five European countries (Germany, Italy, the Netherlands, Portugal and Sweden) a random sample from the general population aged 18-74 years was drawn. In total, 12 377 subjects were interviewed in this cross-sectional study and a random sample (n = 3119) was patch tested using the TRUE Test and Finn Chamber techniques. Patch test procedures were harmonized by mandatory training before the study and monitoring during the study. The highest prevalence for contact allergy of 2·6% [95% confidence interval (CI) 2·1-3·2] was found for fragrance mix (FM) I in petrolatum, with a high content of atranol and chloratranol, followed by 1·9% (95% CI 1·5-2·4) for FM II in petrolatum. The conservatively estimated prevalence of fragrance contact allergy was 1·9% (95% CI 1·5-2·5). This is defined as the existence of a positive patch test to FM I or FM II; any of their individual materials; Myroxylon pereirae; sesquiterpene lactones or 3- and 4-hydroxyisohexyl 3-cyclohexene carboxaldehyde that show clinical relevance, defined conservatively as lifetime avoidance of scented products and an itchy skin rash lasting > 3 days in a lifetime. Using the reported lifetime prevalence of any contact dermatitis instead of the lifetime prevalence of any itchy skin rash, the prevalence is 0·8% (95% CI 0·5-1·2). The prevalence rates of contact allergy to fragrances in women are about twice those in men. This study helps to identify targets for prevention of fragrance allergy. © 2015 British Association of Dermatologists.
Heuristics, Anecdote and Applying Art: Why War Theorists are Kidding Themselves
2009-03-17
century author and futurist Isaac Asimov . Pareto was able to demonstrate the non-random (or non-Gaussian) distribution of wealth in various European...societies, and conclude that this represented a general feature of human populations.19 Asimov suggested that human behavior might be modeled in the...population as well. 20 Isaac Asimov , Foundation (New York: Gnome Press, 1951). Asimov described (in admittedly vague terms) a theory of psychohistory, which
Animal social networks as substrate for cultural behavioural diversity.
Whitehead, Hal; Lusseau, David
2012-02-07
We used individual-based stochastic models to examine how social structure influences the diversity of socially learned behaviour within a non-human population. For continuous behavioural variables we modelled three forms of dyadic social learning, averaging the behavioural value of the two individuals, random transfer of information from one individual to the other, and directional transfer from the individual with highest behavioural value to the other. Learning had potential error. We also examined the transfer of categorical behaviour between individuals with random directionality and two forms of error, the adoption of a randomly chosen existing behavioural category or the innovation of a new type of behaviour. In populations without social structuring the diversity of culturally transmitted behaviour increased with learning error and population size. When the populations were structured socially either by making individuals members of permanent social units or by giving them overlapping ranges, behavioural diversity increased with network modularity under all scenarios, although the proportional increase varied considerably between continuous and categorical behaviour, with transmission mechanism, and population size. Although functions of the form e(c)¹(m)⁻(c)² + (c)³(Log(N)) predicted the mean increase in diversity with modularity (m) and population size (N), behavioural diversity could be highly unpredictable both between simulations with the same set of parameters, and within runs. Errors in social learning and social structuring generally promote behavioural diversity. Consequently, social learning may be considered to produce culture in populations whose social structure is sufficiently modular. Copyright © 2011 Elsevier Ltd. All rights reserved.
Vincenzi, Simone; Mangel, Marc; Crivelli, Alain J; Munch, Stephan; Skaug, Hans J
2014-09-01
The differences in demographic and life-history processes between organisms living in the same population have important consequences for ecological and evolutionary dynamics. Modern statistical and computational methods allow the investigation of individual and shared (among homogeneous groups) determinants of the observed variation in growth. We use an Empirical Bayes approach to estimate individual and shared variation in somatic growth using a von Bertalanffy growth model with random effects. To illustrate the power and generality of the method, we consider two populations of marble trout Salmo marmoratus living in Slovenian streams, where individually tagged fish have been sampled for more than 15 years. We use year-of-birth cohort, population density during the first year of life, and individual random effects as potential predictors of the von Bertalanffy growth function's parameters k (rate of growth) and L∞ (asymptotic size). Our results showed that size ranks were largely maintained throughout marble trout lifetime in both populations. According to the Akaike Information Criterion (AIC), the best models showed different growth patterns for year-of-birth cohorts as well as the existence of substantial individual variation in growth trajectories after accounting for the cohort effect. For both populations, models including density during the first year of life showed that growth tended to decrease with increasing population density early in life. Model validation showed that predictions of individual growth trajectories using the random-effects model were more accurate than predictions based on mean size-at-age of fish.
Cunningham, John A; Leatherdale, Scott T; Selby, Peter L; Tyndale, Rachel F; Zawertailo, Laurie; Kushnir, Vladyslav
2011-09-28
Considerable public health efforts are ongoing Canada-wide to reduce the prevalence of smoking in the general population. From 1985 to 2005, smoking rates among adults decreased from 35% to 19%, however, since that time, the prevalence has plateaued at around 18-19%. To continue to reduce the number of smokers at the population level, one option has been to translate interventions that have demonstrated clinical efficacy into population level initiatives. Nicotine Replacement Therapy (NRT) has a considerable clinical research base demonstrating its efficacy and safety and thus public health initiatives in Canada and other countries are distributing NRT widely through the mail. However, one important question remains unanswered--do smoking cessation programs that involve mailed distribution of free NRT work? To answer this question, a randomized controlled trial is required. A single blinded, panel survey design with random assignment to an experimental and a control condition will be used in this study. A two-stage recruitment process will be employed, in the context of a general population survey with two follow-ups (8 weeks and 6 months). Random digit dialing of Canadian home telephone numbers will identify households with adult smokers (aged 18+ years) who are willing to take part in a smoking study that involves three interviews, with saliva collection for 3-HC/cotinine ratio measurement at baseline and saliva cotinine verification at 8-week and 6-month follow-ups (N = 3,000). Eligible subjects interested in free NRT will be determined at baseline (N = 1,000) and subsequently randomized into experimental and control conditions to receive versus not receive nicotine patches. The primary hypothesis is that subjects who receive nicotine patches will display significantly higher quit rates (as assessed by 30 day point prevalence of abstinence from tobacco) at 6-month follow-up as compared to subjects who do not receive nicotine patches at baseline. The findings from the proposed trial are timely and highly relevant as mailed distribution of NRT require considerable resources and there are limited public health dollars available to combat this substantial health concern. In addition, findings from this randomized controlled trial will inform the development of models to engage smokers to quit, incorporating proactive recruitment and the offer of evidence based treatment. ClinicalTrials.gov: NCT01429129.
Shteingart, Hanan; Loewenstein, Yonatan
2016-01-01
There is a long history of experiments in which participants are instructed to generate a long sequence of binary random numbers. The scope of this line of research has shifted over the years from identifying the basic psychological principles and/or the heuristics that lead to deviations from randomness, to one of predicting future choices. In this paper, we used generalized linear regression and the framework of Reinforcement Learning in order to address both points. In particular, we used logistic regression analysis in order to characterize the temporal sequence of participants' choices. Surprisingly, a population analysis indicated that the contribution of the most recent trial has only a weak effect on behavior, compared to more preceding trials, a result that seems irreconcilable with standard sequential effects that decay monotonously with the delay. However, when considering each participant separately, we found that the magnitudes of the sequential effect are a monotonous decreasing function of the delay, yet these individual sequential effects are largely averaged out in a population analysis because of heterogeneity. The substantial behavioral heterogeneity in this task is further demonstrated quantitatively by considering the predictive power of the model. We show that a heterogeneous model of sequential dependencies captures the structure available in random sequence generation. Finally, we show that the results of the logistic regression analysis can be interpreted in the framework of reinforcement learning, allowing us to compare the sequential effects in the random sequence generation task to those in an operant learning task. We show that in contrast to the random sequence generation task, sequential effects in operant learning are far more homogenous across the population. These results suggest that in the random sequence generation task, different participants adopt different cognitive strategies to suppress sequential dependencies when generating the "random" sequences.
A Spatio-Temporally Explicit Random Encounter Model for Large-Scale Population Surveys
Jousimo, Jussi; Ovaskainen, Otso
2016-01-01
Random encounter models can be used to estimate population abundance from indirect data collected by non-invasive sampling methods, such as track counts or camera-trap data. The classical Formozov–Malyshev–Pereleshin (FMP) estimator converts track counts into an estimate of mean population density, assuming that data on the daily movement distances of the animals are available. We utilize generalized linear models with spatio-temporal error structures to extend the FMP estimator into a flexible Bayesian modelling approach that estimates not only total population size, but also spatio-temporal variation in population density. We also introduce a weighting scheme to estimate density on habitats that are not covered by survey transects, assuming that movement data on a subset of individuals is available. We test the performance of spatio-temporal and temporal approaches by a simulation study mimicking the Finnish winter track count survey. The results illustrate how the spatio-temporal modelling approach is able to borrow information from observations made on neighboring locations and times when estimating population density, and that spatio-temporal and temporal smoothing models can provide improved estimates of total population size compared to the FMP method. PMID:27611683
Löve, Jesper; Hensing, Gunnel; Holmgren, Kristina; Torén, Kjell
2013-06-05
Some previous studies have proposed potential explanatory factors for the social gradient in sickness absence. Yet, this research area is still in its infancy and in order to comprise the full range of socioeconomic positions there is a need for studies conducted on random population samples. The main aim of the present study was to investigate if somatic and mental symptoms, mental wellbeing, job strain, and physical work environment could explain the association between low socioeconomic position and belonging to a sample of new cases of sick-listed employees. This study was conducted on one random working population sample (n = 2763) and one sample of newly sick-listed cases of employees (n = 3044), drawn from the same random general population in western Sweden. Explanatory factors were self-rated 'Somatic and mental symptoms', 'Mental well-being', 'job strain', and 'physical work conditions' (i.e. heavy lifting and awkward work postures). Multiple logistic regression analyses were used. Somatic and mental symptoms, mental well-being, and job strain, could not explain the association between socioeconomic position and sickness absence in both women and men. However, physical work conditions explained the total association in women and much of this association in men. In men the gradient between Non-skilled manual OR 1.76 (1.24;2.48) and Skilled manual OR 1.59 (1.10;2.20), both in relation to Higher non-manual, remained unexplained. The present study strengthens the scientific evidence that social differences in physical work conditions seem to comprise a key element of the social gradient in sickness absence, particularly in women. Future studies should try to identify further predictors for this gradient in men.
Liu, Wei; Ding, Jinhui
2018-04-01
The application of the principle of the intention-to-treat (ITT) to the analysis of clinical trials is challenged in the presence of missing outcome data. The consequences of stopping an assigned treatment in a withdrawn subject are unknown. It is difficult to make a single assumption about missing mechanisms for all clinical trials because there are complicated reactions in the human body to drugs due to the presence of complex biological networks, leading to data missing randomly or non-randomly. Currently there is no statistical method that can tell whether a difference between two treatments in the ITT population of a randomized clinical trial with missing data is significant at a pre-specified level. Making no assumptions about the missing mechanisms, we propose a generalized complete-case (GCC) analysis based on the data of completers. An evaluation of the impact of missing data on the ITT analysis reveals that a statistically significant GCC result implies a significant treatment effect in the ITT population at a pre-specified significance level unless, relative to the comparator, the test drug is poisonous to the non-completers as documented in their medical records. Applications of the GCC analysis are illustrated using literature data, and its properties and limits are discussed.
Working situation of cancer survivors versus the general population.
Lee, Myung Kyung; Yun, Young Ho
2015-06-01
The purposes of this study were to compare the working situation of cancer survivors and the general (cancer-free) population and investigate characteristics associated with the increased likelihood of unemployment between the two groups. We selected 1927 cancer survivors from the 2008 Korean Community Health Survey data less than 65 years of age and used propensity score matching to randomly select 1924 individuals from the general population who closely resembled the cancer survivors. Compared to the general population, cancer survivors were less likely to be engaged in paid work, particularly as permanent workers, and were more likely to work regular hours. Additionally, they tended to do less work that involved lifting or moving heavy objects and uncomfortable postures and were more willing to express their emotions. An increased probability of unemployment among cancer survivors was associated with being over 50 years old, being female, having a lower monthly income, having multiple comorbidities, belonging to a nuclear family, being a National Basic Livelihood Act beneficiary, and having a recent diagnosis. Cancer survivors may want to pursue flexible occupations and improve their working situation. Further, they perceive their workplace more positively compared to the general population. Respecting the cancer survivor's choice to find flexible working conditions that suit their health needs and status, health-care providers involved in managing work-related issues among cancer survivors should be aware of the interaction between work-related concerns and post-cancer disease management.
ERIC Educational Resources Information Center
Behlol, Malik Ghulam; Anwar, Mohammad
2011-01-01
The study was conducted to compare the teaching methods and evaluation practices in English subject at secondary school certificate (SSC) and general certificate of education GCE-O-level in Pakistan. The population of the study was students, teachers and experts at SSC and 0-level in the Punjab province. Purposive and random sampling techniques…
Nagano, Yasuharu; Yako-Suketomo, Hiroko; Natsui, Hiroaki
2018-01-01
Raising awareness on a disorder is important for its prevention and for promoting public health. However, for sports injuries like the anterior cruciate ligament (ACL) injury no studies have investigated the awareness on risk factors for injury and possible preventative measures in the general population. The sources of information among the population are also unclear. The purpose of the present study was to identify these aspects of public awareness about the ACL injury. A questionnaire was randomly distributed among the general population registered with a web based questionnaire supplier, to recruit 900 participants who were aware about the ACL injury. The questionnaire consisted of two parts: Question 1 asked them about their sources of information regarding the ACL injury; Question 2 asked them about the risk factors for ACL injury. Multivariate logistic regression was used to determine the information sources that provide a good understanding of the risk factors. The leading source of information for ACL injury was television (57.0%). However, the results of logistic regression analysis revealed that television was not an effective medium to create awareness about the risk factors, among the general population. Instead "Lecture by a coach", "Classroom session on Health", and "Newspaper" were significantly more effective in creating a good awareness of the risk factors (p < 0.001).
Developing Sampling Frame for Case Study: Challenges and Conditions
ERIC Educational Resources Information Center
Ishak, Noriah Mohd; Abu Bakar, Abu Yazid
2014-01-01
Due to statistical analysis, the issue of random sampling is pertinent to any quantitative study. Unlike quantitative study, the elimination of inferential statistical analysis, allows qualitative researchers to be more creative in dealing with sampling issue. Since results from qualitative study cannot be generalized to the bigger population,…
Self-Efficacy in Incarcerated Adolescents: The Role of Family and Social Supports
ERIC Educational Resources Information Center
Tangeman, Keegan R.; Hall, Susan R.
2011-01-01
This research investigated the role of general and specific self-efficacy factors in positive family relationships and perceived social support within an U.S. incarcerated adolescent population. One hundred African American and Hispanic male adolescent participants, randomly selected from a southern California Probation Department, were included…
Verdurmen, Jacqueline E E; Koning, Ina M; Vollebergh, Wilma A M; van den Eijnden, Regina J J M; Engels, Rutger C M E
2014-03-01
To examine risk moderation of an alcohol intervention targeting parents and adolescents. A cluster randomized trial including 2937 Dutch early adolescents (m=12.68years, SD=0.51) and their parents randomized over four conditions: parent intervention, student intervention, combined parent-student intervention, and control group. 152 classes of 19 high schools in The Netherlands (2006). Moderators at baseline (adolescent: gender, educational level and externalizing behavior; parent: educational level and heavy alcohol use) were used to examine the differential effects of the interventions on onset of (heavy) weekly drinking at 22-month follow-up. The combined intervention effectively delayed the onset of weekly drinking in the general population of adolescents, and was particularly effective in delaying the onset of heavy weekly drinking in a higher-risk subsample of adolescents (i.e. those attending lower levels of education and reporting higher levels of externalizing behavior). Present and previous results have established the combined intervention to be universally effective in postponing weekly alcohol use among Dutch adolescents, with an added effect on postponing heavy weekly drinking in high risk subgroups. Therefore, implementation of this intervention in the general population of schools in The Netherlands is advised. NTR649. Copyright © 2013 Elsevier Inc. All rights reserved.
Miao, Ning; Liu, Shi-Rong; Shi, Zuo-Min; Yu, Hong; Liu, Xing-Liang
2009-06-01
Based on the investigation in a 4 hm2 Betula-Abies forest plot in sub-alpine area in West Sichuan of China, and by using point pattern analysis method in terms of O-ring statistics, the spatial patterns of dominant species Betula albo-sinensis and Abies faxoniana in different age classes in study area were analyzed, and the intra- and inter-species associations between these age classes were studied. B. albo-sinensis had a unimodal distribution of its DBH frequency, indicating a declining population, while A. faxoniana had a reverse J-shaped pattern, showing an increasing population. All the big trees of B. albo-sinensis and A. faxoniana were spatially in random at all scales, while the medium age and small trees were spatially clumped at small scales and tended to be randomly or evenly distributed with increasing spatial scale. The maximum aggregation degree decreased with increasing age class. Spatial association mainly occurred at small scales. A. faxoniana generally showed positive intra-specific association, while B. albo-sinensis generally showed negative intra-specific association. For the two populations, big and small trees had no significant spatial association, but middle age trees had negative spatial association. Negative inter-specific associations of the two populations were commonly found in different age classes. The larger the difference of age class, the stronger the negative inter-specific association.
Health indicators: eliminating bias from convenience sampling estimators.
Hedt, Bethany L; Pagano, Marcello
2011-02-28
Public health practitioners are often called upon to make inference about a health indicator for a population at large when the sole available information are data gathered from a convenience sample, such as data gathered on visitors to a clinic. These data may be of the highest quality and quite extensive, but the biases inherent in a convenience sample preclude the legitimate use of powerful inferential tools that are usually associated with a random sample. In general, we know nothing about those who do not visit the clinic beyond the fact that they do not visit the clinic. An alternative is to take a random sample of the population. However, we show that this solution would be wasteful if it excluded the use of available information. Hence, we present a simple annealing methodology that combines a relatively small, and presumably far less expensive, random sample with the convenience sample. This allows us to not only take advantage of powerful inferential tools, but also provides more accurate information than that available from just using data from the random sample alone. Copyright © 2011 John Wiley & Sons, Ltd.
Intervention-Based Stochastic Disease Eradication
NASA Astrophysics Data System (ADS)
Billings, Lora; Mier-Y-Teran-Romero, Luis; Lindley, Brandon; Schwartz, Ira
2013-03-01
Disease control is of paramount importance in public health with infectious disease extinction as the ultimate goal. Intervention controls, such as vaccination of susceptible individuals and/or treatment of infectives, are typically based on a deterministic schedule, such as periodically vaccinating susceptible children based on school calendars. In reality, however, such policies are administered as a random process, while still possessing a mean period. Here, we consider the effect of randomly distributed intervention as disease control on large finite populations. We show explicitly how intervention control, based on mean period and treatment fraction, modulates the average extinction times as a function of population size and the speed of infection. In particular, our results show an exponential improvement in extinction times even though the controls are implemented using a random Poisson distribution. Finally, we discover those parameter regimes where random treatment yields an exponential improvement in extinction times over the application of strictly periodic intervention. The implication of our results is discussed in light of the availability of limited resources for control. Supported by the National Institute of General Medical Sciences Award No. R01GM090204
Overall mortality among patients surviving an episode of peptic ulcer bleeding
Ruigomez, A.; Rodriguez, L. A.; Hasselgren, G.; Johansson, S.; Wallander, M.
2000-01-01
STUDY OBJECTIVE—The authors investigated whether patients who have survived an acute episode of peptic ulcer bleeding (PUB) have an excess long term all cause mortality compared with the general population free of PUB. DESIGN—Follow up study of previously identified cohort of patients with a PUB episode and a general population cohort. SETTING—The source population included all people aged 30 to 89 years, registered with general practitioners in the United Kingdom. PATIENTS—All patients alive one month after the PUB episode constituted the cohort of PUB patients (n=978). A control group of 5000 people was randomly sampled from the source population. The same eligibility criteria as for patients with PUB were applied to the control series. Also, controls had to be free of PUB before start date. MAIN RESULTS—Relative risk of mortality among PUB patients was 2.1, 95%CI: 1.7, 2.6) compared with the general population. This increased mortality risk occurred mainly in the patients less than 60 years old. No difference was observed between men and women. The excess mortality was not only circumscribed to deaths attributable to recurrent gastrointestinal bleed, but also cardiovascular, cancer and other causes. CONCLUSIONS—People who have survived an acute episode of PUB have a reduced long term survival compared with the general population.This reduction was stronger among middle age patients than in the elderly. Keywords: cohort study; mortality; peptic ulcer; bleeding; population-based study PMID:10715746
Nonlinear subdiffusive fractional equations and the aggregation phenomenon.
Fedotov, Sergei
2013-09-01
In this article we address the problem of the nonlinear interaction of subdiffusive particles. We introduce the random walk model in which statistical characteristics of a random walker such as escape rate and jump distribution depend on the mean density of particles. We derive a set of nonlinear subdiffusive fractional master equations and consider their diffusion approximations. We show that these equations describe the transition from an intermediate subdiffusive regime to asymptotically normal advection-diffusion transport regime. This transition is governed by nonlinear tempering parameter that generalizes the standard linear tempering. We illustrate the general results through the use of the examples from cell and population biology. We find that a nonuniform anomalous exponent has a strong influence on the aggregation phenomenon.
Udonwa, N. E.; Uko, E. K.; Ikpeme, B. M.; Ibanga, I. A.; Okon, B. O.
2009-01-01
A population-based-cross-sectional survey was carried out to investigate the potential risk of exposure to premium motor spirit (PMS) fumes in Calabar, Nigeria, among Automobile Mechanics (AM), Petrol Station Attendants (PSA) and the general population. Structured questionnaire was administered on the randomly chosen subjects to elicit information on their exposure to PMS. Duration of exposure was taken as the length of work in their various occupations. Venous blood was taken for methaemoglobin (MetHb) and packed cells volume (PCV). Mean MetHb value was higher in AM (7.3%) and PSA (5.8%) than in the subjects from the general population (2.7%). PCV was lower in PSA (30.8%), than AM (33.3%) and the subjects from the general population (40.8%). MetHb level was directly proportional, and PCV inversely related, to the duration of exposure. The study suggested increased exposure to petrol fumes among AM, PSA, and MetHb as a useful biomarker in determining the level of exposure to benzene in petrol vapour. PMID:19936128
Yiu, Sean; Farewell, Vernon T; Tom, Brian D M
2017-08-01
Many psoriatic arthritis patients do not progress to permanent joint damage in any of the 28 hand joints, even under prolonged follow-up. This has led several researchers to fit models that estimate the proportion of stayers (those who do not have the propensity to experience the event of interest) and to characterize the rate of developing damaged joints in the movers (those who have the propensity to experience the event of interest). However, when fitted to the same data, the paper demonstrates that the choice of model for the movers can lead to widely varying conclusions on a stayer population, thus implying that, if interest lies in a stayer population, a single analysis should not generally be adopted. The aim of the paper is to provide greater understanding regarding estimation of a stayer population by comparing the inferences, performance and features of multiple fitted models to real and simulated data sets. The models for the movers are based on Poisson processes with patient level random effects and/or dynamic covariates, which are used to induce within-patient correlation, and observation level random effects are used to account for time varying unobserved heterogeneity. The gamma, inverse Gaussian and compound Poisson distributions are considered for the random effects.
Smith, Caren E; Coltell, Oscar; Sorlí, Jose V; Estruch, Ramón; Martínez-González, Miguel Ángel; Salas-Salvadó, Jordi; Fitó, Montserrat; Arós, Fernando; Dashti, Hassan S; Lai, Chao Q; Miró, Leticia; Serra-Majem, Lluís; Gómez-Gracia, Enrique; Fiol, Miquel; Ros, Emilio; Aslibekyan, Stella; Hidalgo, Bertha; Neuhouser, Marian L; Di, Chongzhi; Tucker, Katherine L; Arnett, Donna K; Ordovás, José M; Corella, Dolores
2016-09-14
Controversy persists on the association between dairy products, especially milk, and cardiovascular diseases (CVD). Genetic proxies may improve dairy intake estimations, and clarify diet-disease relationships through Mendelian randomization. We meta-analytically (n ≤ 20,089) evaluated associations between a lactase persistence (LP) SNP, the minichromosome maintenance complex component 6 (MCM6)-rs3754686C>T (nonpersistence>persistence), dairy intake, and CVD biomarkers in American (Hispanics, African-American and Whites) and Mediterranean populations. Moreover, we analyzed longitudinal associations with milk, CVD and mortality in PREDIMED), a randomized Mediterranean diet (MedDiet) intervention trial (n = 7185). The MCM6-rs3754686/MCM6-rs309180 (as proxy), LP-allele (T) was strongly associated with higher milk intake, but inconsistently associated with glucose and lipids, and not associated with CVD or total mortality in the whole population. Heterogeneity analyses suggested some sex-specific associations. The T-allele was associated with higher CVD and mortality risk in women but not in men (P-sex interaction:0.005 and 0.032, respectively), mainly in the MedDiet group. However, milk intake was not associated with CVD biomarkers, CVD or mortality either generally or in sub-groups. Although MCM6-rs3754686 is a good milk intake proxy in these populations, attributing its associations with CVD and mortality in Mediterranean women to milk is unwarranted, as other factors limiting the assumption of causality in Mendelian randomization may exist.
Hay, Jennifer L; Berwick, Marianne; Zielaskowski, Kate; White, Kirsten Am; Rodríguez, Vivian M; Robers, Erika; Guest, Dolores D; Sussman, Andrew; Talamantes, Yvonne; Schwartz, Matthew R; Greb, Jennie; Bigney, Jessica; Kaphingst, Kimberly A; Hunley, Keith; Buller, David B
2017-04-25
Limited translational genomic research currently exists to guide the availability, comprehension, and appropriate use of personalized genomics in diverse general population subgroups. Melanoma skin cancers are preventable, curable, common in the general population, and disproportionately increasing in Hispanics. Variants in the melanocortin-1 receptor (MC1R) gene are present in approximately 50% of the population, are major factors in determining sun sensitivity, and confer a 2-to-3-fold increase in melanoma risk in the general population, even in populations with darker skin. Therefore, feedback regarding MC1R risk status may raise risk awareness and protective behavior in the general population. We are conducting a randomized controlled trial examining Internet presentation of the risks and benefits of personalized genomic testing for MC1R gene variants that are associated with increased melanoma risk. We will enroll a total of 885 participants (462 participants are currently enrolled), who will be randomized 6:1 to personalized genomic testing for melanoma risk versus waiting list control. Control participants will be offered testing after outcome assessments. Participants will be balanced across self-reported Hispanic versus non-Hispanic ethnicity (n=750 in personalized genomic testing for melanoma risk arm; n=135 in control arm), and will be recruited from a general population cohort in Albuquerque, New Mexico, which is subject to year-round sun exposure. Baseline surveys will be completed in-person with study staff and follow-up measures will be completed via telephone. Aim 1 of the trial will examine the personal utility of personalized genomic testing for melanoma risk in terms of short-term (3-month) sun protection and skin screening behaviors, family and physician communication, and melanoma threat and control beliefs (ie, putative mediators of behavior change). We will also examine potential unintended consequences of testing among those who receive average-risk personalized genomic testing for melanoma risk findings, and examine predictors of sun protection at 3 months as the outcome. These findings will be used to develop messages for groups that receive average-risk feedback. Aim 2 will compare rates of test consideration in Hispanics versus non-Hispanics, including consideration of testing pros and cons and registration of a decision to either accept or decline testing. Aim 3 will examine personalized genomic testing for melanoma risk feedback comprehension, recall, satisfaction, and cancer-related distress in those who undergo testing, and whether these outcomes differ by ethnicity (Hispanic vs non-Hispanic), or sociocultural or demographic factors. Final outcome data collection is anticipated to be complete by October 2017, at which point data analysis will commence. This study has important implications for personalized genomics in the context of melanoma risk, and may be broadly applicable as a model for delivery of personalized genomic feedback for other health conditions. ©Jennifer L Hay, Marianne Berwick, Kate Zielaskowski, Kirsten AM White, Vivian M Rodríguez, Erika Robers, Dolores D Guest, Andrew Sussman, Yvonne Talamantes, Matthew R Schwartz, Jennie Greb, Jessica Bigney, Kimberly A Kaphingst, Keith Hunley, David B Buller. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 25.04.2017.
Preliminary trial of the effect of general practice based nutritional advice.
Baron, J A; Gleason, R; Crowe, B; Mann, J I
1990-01-01
Despite formal recommendations for dietary change to reduce the incidence of ischaemic heart disease, the acceptability and effectiveness of the proposed diets have not been well investigated in population based studies. In this preliminary investigation of nutritional advice in a well population, subjects in one group practice were randomized to receive either dietary instruction or simple follow up without instruction. The dietary recommendations were well received, and a substantial proportion of subjects reported altering their diets in accordance with them. There were modest beneficial changes in plasma lipid levels among men. Thus, using general practice as an avenue for promoting dietary change is feasible, and may be effective among men. PMID:2115348
Vincenzi, Simone; Mangel, Marc; Crivelli, Alain J.; Munch, Stephan; Skaug, Hans J.
2014-01-01
The differences in demographic and life-history processes between organisms living in the same population have important consequences for ecological and evolutionary dynamics. Modern statistical and computational methods allow the investigation of individual and shared (among homogeneous groups) determinants of the observed variation in growth. We use an Empirical Bayes approach to estimate individual and shared variation in somatic growth using a von Bertalanffy growth model with random effects. To illustrate the power and generality of the method, we consider two populations of marble trout Salmo marmoratus living in Slovenian streams, where individually tagged fish have been sampled for more than 15 years. We use year-of-birth cohort, population density during the first year of life, and individual random effects as potential predictors of the von Bertalanffy growth function's parameters k (rate of growth) and (asymptotic size). Our results showed that size ranks were largely maintained throughout marble trout lifetime in both populations. According to the Akaike Information Criterion (AIC), the best models showed different growth patterns for year-of-birth cohorts as well as the existence of substantial individual variation in growth trajectories after accounting for the cohort effect. For both populations, models including density during the first year of life showed that growth tended to decrease with increasing population density early in life. Model validation showed that predictions of individual growth trajectories using the random-effects model were more accurate than predictions based on mean size-at-age of fish. PMID:25211603
Fowkes, F G; Lowe, G D; Rumley, A; Lennie, S E; Smith, F B; Donnan, P T
1993-05-01
Blood viscosity is elevated in hypertensive subjects, but the association of viscosity with arterial blood pressure in the general population, and the influence of social, lifestyle and disease characteristics on this association, are not established. In the Edinburgh Artery Study, 1592 men and women aged 55-74 years selected randomly from the general population attended a university clinic. A fasting blood sample was taken for the measurement of blood viscosity and its major determinants (haematocrit, plasma viscosity and fibrinogen). Systolic pressure was related univariately to blood viscosity (P < 0.001), plasma viscosity (P < 0.001) and plasma fibrinogen (P < 0.01), but the association with fibrinogen did not persist after adjusting for body mass index. Diastolic pressure was related univariately to blood viscosity (P < 0.001) and plasma viscosity (P < 0.001) and haematocrit (P < 0.001) but not to fibrinogen. The only difference between the sexes was that the association between blood viscosity and systolic pressure was confined to males. Blood viscosity was associated equally with systolic and diastolic pressures in males, and remained independently related on multivariate analysis adjusting for age, sex, body mass index, social class, smoking, alcohol intake, exercise, angina, HDL and non-HDL cholesterol, diabetes mellitus, plasma viscosity, fibrinogen, and haematocrit.
NASA Technical Reports Server (NTRS)
Johnson, R. A.; Wehrly, T.
1976-01-01
Population models for dependence between two angular measurements and for dependence between an angular and a linear observation are proposed. The method of canonical correlations first leads to new population and sample measures of dependence in this latter situation. An example relating wind direction to the level of a pollutant is given. Next, applied to pairs of angular measurements, the method yields previously proposed sample measures in some special cases and a new sample measure in general.
Is Knowledge Random? Introducing Sampling and Bias through Outdoor Inquiry
ERIC Educational Resources Information Center
Stier, Sam
2010-01-01
Sampling, very generally, is the process of learning about something by selecting and assessing representative parts of that population or object. In the inquiry activity described here, students learned about sampling techniques as they estimated the number of trees greater than 12 cm dbh (diameter at breast height) in a wooded, discrete area…
Physical Health Effects of Intimate Partner Abuse
ERIC Educational Resources Information Center
Sillito, Carrie LeFevre
2012-01-01
Although intimate partner violence has been recognized as both a social problem and health issue, the extent to which it is a health issue for both males and females in the general population is largely unknown. This longitudinal research uses data from the National Survey of Family and Households (1987-2003). Random effects logistic regression…
ERIC Educational Resources Information Center
Webb, Monica S.; de Ybarra, Denise Rodriguez; Baker, Elizabeth A.; Reis, Isildinha M.; Carey, Michael P.
2010-01-01
Objective: The health consequences of tobacco smoking disproportionately affect African Americans, but research on whether efficacious interventions can be generalized to this population is limited. This study examined the efficacy of group-based cognitive-behavioral therapy (CBT) for smoking cessation among African Americans. Method: Participants…
Foray search: an effective systematic dispersal strategy in fragmented landscapes
L. Conradt; P.A. Zollner; T.J. Roper; C.D. Thomas
2003-01-01
In the absence of evidence to the contrary, population models generally assume that the dispersal trajectories of animals are random, but systematic dispersal could be more efficient at detecting new habitat and may therefore constitute a more realistic assumption. Here, we investigate, by means of simulations, the properties of a potentially widespread systematic...
Simulation-Extrapolation for Estimating Means and Causal Effects with Mismeasured Covariates
ERIC Educational Resources Information Center
Lockwood, J. R.; McCaffrey, Daniel F.
2015-01-01
Regression, weighting and related approaches to estimating a population mean from a sample with nonrandom missing data often rely on the assumption that conditional on covariates, observed samples can be treated as random. Standard methods using this assumption generally will fail to yield consistent estimators when covariates are measured with…
Implications of Small Samples for Generalization: Adjustments and Rules of Thumb
ERIC Educational Resources Information Center
Tipton, Elizabeth; Hallberg, Kelly; Hedges, Larry V.; Chan, Wendy
2015-01-01
Policy-makers are frequently interested in understanding how effective a particular intervention may be for a specific (and often broad) population. In many fields, particularly education and social welfare, the ideal form of these evaluations is a large-scale randomized experiment. Recent research has highlighted that sites in these large-scale…
Nonsuicidal Self-Injury in a College Population: General Trends and Sex Differences
ERIC Educational Resources Information Center
Whitlock, Janis; Muehlenkamp, Jennifer; Purington, Amanda; Eckenrode, John; Barreira, Paul; Abrams, Gina Baral; Marchell, Tim; Kress, Victoria; Girard, Kristine; Chin, Calvin; Knox, Kerry
2011-01-01
Objective: To describe basic nonsuicidal self-injury (NSSI) characteristics and to explore sex differences. Methods: A random sample from 8 universities were invited to participate in a Web-based survey in 2006-2007; 38.9% (n = 14,372) participated. Analysis assessed sex differences in NSSI prevalence, practices, severity, perceived dependency,…
It's a Girl! Random Numbers, Simulations, and the Law of Large Numbers
ERIC Educational Resources Information Center
Goodwin, Chris; Ortiz, Enrique
2015-01-01
Modeling using mathematics and making inferences about mathematical situations are becoming more prevalent in most fields of study. Descriptive statistics cannot be used to generalize about a population or make predictions of what can occur. Instead, inference must be used. Simulation and sampling are essential in building a foundation for…
The use of computerized birthday greeting reminders in the management of diabetes.
Lafata, Jennifer Elston; Baker, Ann M; Divine, George W; McCarthy, Bruce D; Xi, Hugo
2002-07-01
Although mailed reminders have been used for prevention among general populations, few studies have evaluated their effectiveness among chronically ill populations. We evaluated the effectiveness of mailed reminders for improving diabetes management. The reminder included a letter from the individual's primary care physician (PCP), a self-care handbook, a preventive care checklist, and specific recommendations regarding receipt of routine monitoring and screening. Of 195 PCPs practicing with a large group practice, 111 agreed to have their adult patients with diabetes randomized to receive the reminder (n = 1,641) or usual care (n = 1,668). Using data from automated databases, we fit generalized estimating equations to evaluate the effect of reminder receipt on fasting lipid profile and glycated hemoglobin testing, dilated retinal exam receipt, and visit frequency during the 6 and 12 months following randomization, and glycated hemoglobin and cholesterol levels in the year following randomization. Reminder and usual care recipients did not differ in sociodemographic, clinical, or prior testing characteristics. In the 6 months following randomization, reminder recipients were more likely to receive a retinal exam (odds ratio [OR], 1.29; 95% confidence interval [95% CI], 1.12 to 1.49) and diabetes visit (OR, 1.28; 95% CI, 1.12 to 1.47). In the 12 months following randomization, reminder recipients were more likely to receive a glycated hemoglobin test (OR, 1.21; 95% CI, 1.03 to 1.43), retinal exam (OR, 1.23; 95% CI, 1.07 to 1.41), and diabetes visit (OR, 1.25; 95% CI, 1.09 to 1.29). In the follow-up year, reminder recipients also tended to have a glycated hemoglobin test that did not reflect poor control (<9.5%). We found small but significant improvements in the management of patients with diabetes receiving a computerized mailed reminder.
Emergence of a spectral gap in a class of random matrices associated with split graphs
NASA Astrophysics Data System (ADS)
Bassler, Kevin E.; Zia, R. K. P.
2018-01-01
Motivated by the intriguing behavior displayed in a dynamic network that models a population of extreme introverts and extroverts (XIE), we consider the spectral properties of ensembles of random split graph adjacency matrices. We discover that, in general, a gap emerges in the bulk spectrum between -1 and 0 that contains a single eigenvalue. An analytic expression for the bulk distribution is derived and verified with numerical analysis. We also examine their relation to chiral ensembles, which are associated with bipartite graphs.
Clagett, Bartholt; Nathanson, Katherine L.; Ciosek, Stephanie L.; McDermoth, Monique; Vaughn, David J.; Mitra, Nandita; Weiss, Andrew; Martonik, Rachel; Kanetsky, Peter A.
2013-01-01
Random-digit dialing (RDD) using landline telephone numbers is the historical gold standard for control recruitment in population-based epidemiologic research. However, increasing cell-phone usage and diminishing response rates suggest that the effectiveness of RDD in recruiting a random sample of the general population, particularly for younger target populations, is decreasing. In this study, we compared landline RDD with alternative methods of control recruitment, including RDD using cell-phone numbers and address-based sampling (ABS), to recruit primarily white men aged 18–55 years into a study of testicular cancer susceptibility conducted in the Philadelphia, Pennsylvania, metropolitan area between 2009 and 2012. With few exceptions, eligible and enrolled controls recruited by means of RDD and ABS were similar with regard to characteristics for which data were collected on the screening survey. While we find ABS to be a comparably effective method of recruiting young males compared with landline RDD, we acknowledge the potential impact that selection bias may have had on our results because of poor overall response rates, which ranged from 11.4% for landline RDD to 1.7% for ABS. PMID:24008901
Perony, Nicolas; Tessone, Claudio J.; König, Barbara; Schweitzer, Frank
2012-01-01
Out of all the complex phenomena displayed in the behaviour of animal groups, many are thought to be emergent properties of rather simple decisions at the individual level. Some of these phenomena may also be explained by random processes only. Here we investigate to what extent the interaction dynamics of a population of wild house mice (Mus domesticus) in their natural environment can be explained by a simple stochastic model. We first introduce the notion of perceptual landscape, a novel tool used here to describe the utilisation of space by the mouse colony based on the sampling of individuals in discrete locations. We then implement the behavioural assumptions of the perceptual landscape in a multi-agent simulation to verify their accuracy in the reproduction of observed social patterns. We find that many high-level features – with the exception of territoriality – of our behavioural dataset can be accounted for at the population level through the use of this simplified representation. Our findings underline the potential importance of random factors in the apparent complexity of the mice's social structure. These results resonate in the general context of adaptive behaviour versus elementary environmental interactions. PMID:23209394
[Krigle estimation and its simulated sampling of Chilo suppressalis population density].
Yuan, Zheming; Bai, Lianyang; Wang, Kuiwu; Hu, Xiangyue
2004-07-01
In order to draw up a rational sampling plan for the larvae population of Chilo suppressalis, an original population and its two derivative populations, random population and sequence population, were sampled and compared with random sampling, gap-range-random sampling, and a new systematic sampling integrated Krigle interpolation and random original position. As for the original population whose distribution was up to aggregative and dependence range in line direction was 115 cm (6.9 units), gap-range-random sampling in line direction was more precise than random sampling. Distinguishing the population pattern correctly is the key to get a better precision. Gap-range-random sampling and random sampling are fit for aggregated population and random population, respectively, but both of them are difficult to apply in practice. Therefore, a new systematic sampling named as Krigle sample (n = 441) was developed to estimate the density of partial sample (partial estimation, n = 441) and population (overall estimation, N = 1500). As for original population, the estimated precision of Krigle sample to partial sample and population was better than that of investigation sample. With the increase of the aggregation intensity of population, Krigel sample was more effective than investigation sample in both partial estimation and overall estimation in the appropriate sampling gap according to the dependence range.
Löve, Jesper; Holmgren, Kristina; Torén, Kjell; Hensing, Gunnel
2012-03-07
Understanding the reasons for the social gradient in sickness absence might provide an opportunity to reduce the general rates of sickness absence. The complete explanation for this social gradient still remains unclear and there is a need for studies using randomized working population samples. The main aim of the present study was to investigate if self-reported work ability could explain the association between low socioeconomic position and belonging to a sample of new cases of sick-listed employees. The two study samples consisted of a randomized working population (n = 2,763) and a sample of new cases of sick-listed employees (n = 3,044), 19-64 years old. Both samples were drawn from the same randomized general population. Socioeconomic status was measured with occupational position and physical and mental work ability was measured with two items extracted from the work ability index. There was an association between lower socioeconomic status and belonging to the sick-listed sample among both women and men. In men the crude Odds ratios increased for each downwards step in socioeconomic status, OR 1.32 (95% CI 0.98-1.78), OR 1.53 (1.05-2.24), OR 2.80 (2.11-3.72), and OR 2.98 (2.27-3.90). Among women this gradient was not as pronounced. Physical work ability constituted the strongest explanatory factor explaining the total association between socioeconomic status and being sick-listed in women. However, among men, the association between skilled non-manual, OR 2.07 (1.54-2.78), and non-skilled manual, OR 2.03 (1.53-2.71) positions in relation to being sick-listed remained. The explanatory effect of mental work ability was small. Surprisingly, even in the sick-listed sample most respondents had high mental and physical work ability. These results suggest that physical work ability may be an important key in explaining the social gradient in sickness absence, particularly in women. Hence, it is possible that the factors associated with the social gradient in sickness absence may differ, to some extent, between women and men.
Geriatric drug therapy and healthcare utilization in the United kingdom.
Kennerfalk, Anita; Ruigómez, Ana; Wallander, Mari-Ann; Wilhelmsen, Lars; Johansson, Saga
2002-05-01
To describe the use of prescription drug therapy, especially polypharmacy, in an elderly general population; to relate that use to age, gender, and different types of healthcare utilization; and to investigate the influence of selection of different time windows on the result of the quantity as well as the categories of drugs used. Data on a sample of 5000 patients aged 65-90 years in 1996 were derived from the General Practice Research Database (GPRD). The population covered by GPRD is broadly representative of the UK population treated in general practice. Drug use was assessed using 2 time windows - current use of individual drugs on a random day (index date) and 1 month following the index date. Healthcare utilization was analyzed by use of information on visits to general practitioners (GPs), hospitalizations, and referrals to specialists. Women used more drugs than men; however, the prevalence of polypharmacy, defined as concomitant use of > or =5 drugs, was similar in both genders. The most frequently used therapeutic groups were cardiovascular, central nervous, and gastrointestinal system drugs. Almost 80% of both women and men visited a GP at least once a year. Overall, women used more ambulatory care services and men were hospitalized more often. Use of random date compared with 1-month period resulted in a significant underestimation of the amount of drugs used for acute conditions and, consequently, the risk of polypharmacy. The overall results confirm the findings in earlier studies suggesting that the GPRD might be a useful tool in further studies on prescription drug use among elderly persons. More information on the appropriateness of drug use is needed to prevent overuse as well as underuse of medications among the elderly.
Rydvall, Anders; Juth, Niklas; Sandlund, Mikael; Domellöf, Magnus; Lynøe, Niels
2014-02-01
Ethical dilemmas are common in the neonatal intensive care setting. The aim of the present study was to investigate the opinions of Swedish physicians and the general public on treatment decisions regarding a newborn with severe brain damage. We used a vignette-based questionnaire which was sent to a random sample of physicians (n = 628) and the general population (n = 585). Respondents were asked to provide answers as to whether it is acceptable to discontinue ventilator treatment, and when it actually is discontinued whether or not it was acceptable to use drugs which hasten death unintentionally or intentionally. The response rate was 67 % of physicians and 46 % of the general population. A majority of both physicians [56 % (CI 50-62)] and the general population [53 % (CI 49-58)] supported arguments for withdrawing ventilator treatment. A large majority in both groups supported arguments for alleviating the patient's symptoms even if the treatment hastened death, but the two groups display significantly different views on whether or not to provide drugs with the additional intention of hastening death, although the difference disappeared when we compared subgroups of those who were for or against euthanasia-like actions. The study indicated that physicians and the general population have similar opinions regarding discontinuing life-sustaining treatment and providing effective drugs which might unintentionally hasten death but seem to have different views on intentions. The results might be helpful to physicians wanting to examine their own intentions when providing adequate treatment at the end of life.
Kirtadze, Irma; Otiashvili, David; Tabatadze, Mzia; Vardanashvili, Irina; Sturua, Lela; Zabransky, Tomas; Anthony, James C
2018-06-01
Validity of responses in surveys is an important research concern, especially in emerging market economies where surveys in the general population are a novelty, and the level of social control is traditionally higher. The Randomized Response Technique (RRT) can be used as a check on response validity when the study aim is to estimate population prevalence of drug experiences and other socially sensitive and/or illegal behaviors. To apply RRT and to study potential under-reporting of drug use in a nation-scale, population-based general population survey of alcohol and other drug use. For this first-ever household survey on addictive substances for the Country of Georgia, we used the multi-stage probability sampling of 18-to-64-year-old household residents of 111 urban and 49 rural areas. During the interviewer-administered assessments, RRT involved pairing of sensitive and non-sensitive questions about drug experiences. Based upon the standard household self-report survey estimate, an estimated 17.3% [95% confidence interval, CI: 15.5%, 19.1%] of Georgian household residents have tried cannabis. The corresponding RRT estimate was 29.9% [95% CI: 24.9%, 34.9%]. The RRT estimates for other drugs such as heroin also were larger than the standard self-report estimates. We remain unsure about what is the "true" value for prevalence of using illegal psychotropic drugs in the Republic of Georgia study population. Our RRT results suggest that standard non-RRT approaches might produce 'under-estimates' or at best, highly conservative, lower-end estimates. Copyright © 2018 Elsevier B.V. All rights reserved.
Firearm Homicide and Other Causes of Death in Delinquents: A 16-Year Prospective Study
Jakubowski, Jessica A.; Abram, Karen M.; Olson, Nichole D.; Stokes, Marquita L.; Welty, Leah J.
2014-01-01
BACKGROUND: Delinquent youth are at risk for early violent death after release from detention. However, few studies have examined risk factors for mortality. Previous investigations studied only serious offenders (a fraction of the juvenile justice population) and provided little data on females. METHODS: The Northwestern Juvenile Project is a prospective longitudinal study of health needs and outcomes of a stratified random sample of 1829 youth (657 females, 1172 males; 524 Hispanic, 1005 African American, 296 non-Hispanic white, 4 other race/ethnicity) detained between 1995 and 1998. Data on risk factors were drawn from interviews; death records were obtained up to 16 years after detention. We compared all-cause mortality rates and causes of death with those of the general population. Survival analyses were used to examine risk factors for mortality after youth leave detention. RESULTS: Delinquent youth have higher mortality rates than the general population to age 29 years (P < .05), irrespective of gender or race/ethnicity. Females died at nearly 5 times the general population rate (P < .05); Hispanic males and females died at 5 and 9 times the general population rates, respectively (P < .05). Compared with the general population, significantly more delinquent youth died of homicide and its subcategory, homicide by firearm (P < .05). Among delinquent youth, racial/ethnic minorities were at increased risk of homicide compared with non-Hispanic whites (P < .05). Significant risk factors for external-cause mortality and homicide included drug dealing (up to 9 years later), alcohol use disorder, and gang membership (up to a decade later). CONCLUSIONS: Delinquent youth are an identifiable target population to reduce disparities in early violent death. PMID:24936005
Müller, Juliana Dos Santos; Falcão, Ila Rocha; Couto, Maria Carolina Barreto Moreira; Viana, Wendel da Silva; Alves, Ivone Batista; Viola, Denise Nunes; Woods, Courtney Georgette; Rêgo, Rita Franco
2016-05-05
Quality of life is an indicator of how well one perceives that he/she is functioning physically and mentally. The aim of this paper is to determine the health-related quality of life (HRQOL) of artisanal fisherwomen/shellfish gatherers from the Saubara municipality in Bahia, Brazil in comparison to the general population. A structured questionnaire was administered to a sample of 209 artisanal fisherwomen selected at random. The HRQOL questionnaire, known as the 36-Item Short-Form Health Survey version 1 (SF-36v01), was also used, having been translated and verified cross-culturally for the Brazilian population. Sociodemographic, lifestyle and comorbidity information was also collected. Chronic diseases and indicators of musculoskeletal disorders (MSDs) were self-reported. The study population consisted primarily of individuals between 30 and 45 years of age (78%), of self-classified races black or brown (96.2%), with no more than an elementary school education (77%) and married (64.6%). In all the SF-36v01 dimensions, the values in the sample were lower than in the general population of Brazil, which was used as the reference population. In the "Physical Health" domain (Physical Functioning; Physical Role Limitations; Bodily Pain; General Health Perception) a tendency toward a lower health-related quality of life was observed among those who were older, had a lower education level, and had a prevalence of MSDs, hypertension or arthritis. The interference of health conditions linked to the fisherwomen's work activities may contribute to lower HRQOL in all analyzed aspects, in comparison to the general population. In light of these findings, public health policies must consider these informal workers who contribute greatly to Brazil's economy and food system.
General Aviation Aircraft Reliability Study
NASA Technical Reports Server (NTRS)
Pettit, Duane; Turnbull, Andrew; Roelant, Henk A. (Technical Monitor)
2001-01-01
This reliability study was performed in order to provide the aviation community with an estimate of Complex General Aviation (GA) Aircraft System reliability. To successfully improve the safety and reliability for the next generation of GA aircraft, a study of current GA aircraft attributes was prudent. This was accomplished by benchmarking the reliability of operational Complex GA Aircraft Systems. Specifically, Complex GA Aircraft System reliability was estimated using data obtained from the logbooks of a random sample of the Complex GA Aircraft population.
Hay, Jennifer L; Zielaskowski, Kate; Meyer White, Kirsten; Kaphingst, Kimberly; Robers, Erika; Guest, Dolores; Sussman, Andrew; Talamantes, Yvonne; Schwartz, Matthew; Rodríguez, Vivian M; Li, Yuelin; Schofield, Elizabeth; Bigney, Jessica; Hunley, Keith; Buller, David; Berwick, Marianne
2018-06-01
Germline variants in the MC1R gene are common and confer moderate melanoma risk in those with varied skin types. Approaches to precision skin cancer prevention that include genetic information may promote risk awareness and risk reduction in the general population, including Hispanics. To examine prevalence of interest in and uptake of MC1R testing in the general population and examine patterns across demographic and skin cancer risk factors. A randomized clinical trial examined interest in and uptake of MC1R testing among patients at University of New Mexico General Internal Medicine clinics. Study participants were randomized to either a usual-care condition (National Cancer Institute skin cancer pamphlet for diverse skin types) or an MC1R test offer. Participants were registered clinic patients (≥6 months) and English or Spanish fluent. Of the 600 participants recruited to the overall trial, the present study included those 499 participants randomized to the MC1R test offer. Participants were presented with the option to log onto the study website to read 3 educational modules presenting the rationale, benefits, and drawbacks of MC1R testing. Main outcomes include website log on (yes vs no), saliva test kit request (yes vs no), and saliva test kit return for MC1R testing (yes vs no). Demographic and skin cancer risk factors were examined as potential predictors of test interest and uptake. Of the 499 participants (220 [44%] non-Hispanic white, 242 [48%] Hispanic, 396 [79%] female; mean [SD] age, 54 [14.3] years), 232 (46%) elected to learn about MC1R testing by logging onto the website; 204 (88%) of those who logged on decided to request testing; and 167 (82%) of those who requested testing returned the kit. The strongest predictors of website log on were race/ethnicity and education (non-Hispanic whites were more likely to log on [odds ratio for Hispanics vs non-Hispanic whites, 0.5; 95% CI, 0.3-0.7], as were more highly educated individuals [odds ratio for more than high school vs high school or less, 2.7; 95% CI, 1.7-4.3]). The strongest predictor of ordering the test was sunburn history (odds ratio, 5.4; 95% CI, 2.3-12.9 vs no sunburn history). There were moderately high levels of MC1R test interest and uptake in this diverse sample. Addressing potential barriers to testing may be warranted as genomic information becomes integrated into general population approaches to the precision prevention of skin cancer. ClinicalTrials.gov identifier: NCT03130569.
Liu, Xiao-Kun; Xiao, Shui-Yuan; Zhou, Liang; Hu, Mi; Zhou, Wei; Liu, Hui-Ming
2018-01-01
The aims of this study were to investigate the distribution of sleep quality and its relationship with the prevalence of pain among rural Chinese people and to explore the association between sleep quality and pain intensity among the general population in real-life settings. This cross-sectional survey included a total of 2052 adults from rural areas in Liuyang, Hunan Province, recruited through random multistage sampling. The distributions of sleep quality and pain prevalence among the participants over a 4-week period were described. Because of multicollinearity among variables, the influence of self-rated sleep quality and psychosocial covariates on pain intensity was explored using a ridge regression model. The data showed that participants reporting all categories of sleep quality experienced some degree of pain. Sleep quality, along with physical and mental health, was a negative predictor of pain intensity among the general population. Symptoms of depression positively predicted pain intensity. Poor sleep quality increased pain intensity among the participants. Both previous research and the present data suggest that improving sleep quality may significantly decrease pain intensity in the general population. The relationship between sleep and pain may be bidirectional. This finding also suggests that treatment for sleep disorders and insomnia should be addressed in future efforts to alleviate pain intensity.
Kumar, Sanjeev; Karmeshu
2018-04-01
A theoretical investigation is presented that characterizes the emerging sub-threshold membrane potential and inter-spike interval (ISI) distributions of an ensemble of IF neurons that group together and fire together. The squared-noise intensity σ 2 of the ensemble of neurons is treated as a random variable to account for the electrophysiological variations across population of nearly identical neurons. Employing superstatistical framework, both ISI distribution and sub-threshold membrane potential distribution of neuronal ensemble are obtained in terms of generalized K-distribution. The resulting distributions exhibit asymptotic behavior akin to stretched exponential family. Extensive simulations of the underlying SDE with random σ 2 are carried out. The results are found to be in excellent agreement with the analytical results. The analysis has been extended to cover the case corresponding to independent random fluctuations in drift in addition to random squared-noise intensity. The novelty of the proposed analytical investigation for the ensemble of IF neurons is that it yields closed form expressions of probability distributions in terms of generalized K-distribution. Based on a record of spiking activity of thousands of neurons, the findings of the proposed model are validated. The squared-noise intensity σ 2 of identified neurons from the data is found to follow gamma distribution. The proposed generalized K-distribution is found to be in excellent agreement with that of empirically obtained ISI distribution of neuronal ensemble. Copyright © 2018 Elsevier B.V. All rights reserved.
Pooler, P.S.; Smith, D.R.
2005-01-01
We compared the ability of simple random sampling (SRS) and a variety of systematic sampling (SYS) designs to estimate abundance, quantify spatial clustering, and predict spatial distribution of freshwater mussels. Sampling simulations were conducted using data obtained from a census of freshwater mussels in a 40 X 33 m section of the Cacapon River near Capon Bridge, West Virginia, and from a simulated spatially random population generated to have the same abundance as the real population. Sampling units that were 0.25 m 2 gave more accurate and precise abundance estimates and generally better spatial predictions than 1-m2 sampling units. Systematic sampling with ???2 random starts was more efficient than SRS. Estimates of abundance based on SYS were more accurate when the distance between sampling units across the stream was less than or equal to the distance between sampling units along the stream. Three measures for quantifying spatial clustering were examined: Hopkins Statistic, the Clumping Index, and Morisita's Index. Morisita's Index was the most reliable, and the Hopkins Statistic was prone to false rejection of complete spatial randomness. SYS designs with units spaced equally across and up stream provided the most accurate predictions when estimating the spatial distribution by kriging. Our research indicates that SYS designs with sampling units equally spaced both across and along the stream would be appropriate for sampling freshwater mussels even if no information about the true underlying spatial distribution of the population were available to guide the design choice. ?? 2005 by The North American Benthological Society.
Religious characteristics of US women physicians.
Frank, E; Dell, M L; Chopp, R
1999-12-01
Physicians' religious attributes are unknown, and may affect patient care. The Women Physicians' Health Study (WPHS) is a random sample (n = 4501 respondents, 59% response rate) of US women physicians aged 30-70; the first large, national study of US women physicians. In this study US women physicians were less likely to be Christian than were other Americans (61.2% of women physicians versus 85.1% of the general population), but were more likely to be Jewish (13.2% vs 2.0%), Buddhist (1.4% vs 0.3%), Hindu (3.9% vs 0.4%), or atheist/agnostic (5.9% vs 0.6%). Protestantism (29.3% of the population) and Catholicism (24.9%) were the most commonly reported religious identities. The strongest religious identity was claimed by Mormons and Seventh Day Adventists. Thus, women physicians' religious beliefs differ from those of the general population in the US. This may be particularly important for physicians practicing with patient populations with different religious affiliations, and in addressing clinical questions with ethical or religious dimensions.
Dynamics of Competition between Subnetworks of Spiking Neuronal Networks in the Balanced State.
Lagzi, Fereshteh; Rotter, Stefan
2015-01-01
We explore and analyze the nonlinear switching dynamics of neuronal networks with non-homogeneous connectivity. The general significance of such transient dynamics for brain function is unclear; however, for instance decision-making processes in perception and cognition have been implicated with it. The network under study here is comprised of three subnetworks of either excitatory or inhibitory leaky integrate-and-fire neurons, of which two are of the same type. The synaptic weights are arranged to establish and maintain a balance between excitation and inhibition in case of a constant external drive. Each subnetwork is randomly connected, where all neurons belonging to a particular population have the same in-degree and the same out-degree. Neurons in different subnetworks are also randomly connected with the same probability; however, depending on the type of the pre-synaptic neuron, the synaptic weight is scaled by a factor. We observed that for a certain range of the "within" versus "between" connection weights (bifurcation parameter), the network activation spontaneously switches between the two sub-networks of the same type. This kind of dynamics has been termed "winnerless competition", which also has a random component here. In our model, this phenomenon is well described by a set of coupled stochastic differential equations of Lotka-Volterra type that imply a competition between the subnetworks. The associated mean-field model shows the same dynamical behavior as observed in simulations of large networks comprising thousands of spiking neurons. The deterministic phase portrait is characterized by two attractors and a saddle node, its stochastic component is essentially given by the multiplicative inherent noise of the system. We find that the dwell time distribution of the active states is exponential, indicating that the noise drives the system randomly from one attractor to the other. A similar model for a larger number of populations might suggest a general approach to study the dynamics of interacting populations of spiking networks.
Dynamics of Competition between Subnetworks of Spiking Neuronal Networks in the Balanced State
Lagzi, Fereshteh; Rotter, Stefan
2015-01-01
We explore and analyze the nonlinear switching dynamics of neuronal networks with non-homogeneous connectivity. The general significance of such transient dynamics for brain function is unclear; however, for instance decision-making processes in perception and cognition have been implicated with it. The network under study here is comprised of three subnetworks of either excitatory or inhibitory leaky integrate-and-fire neurons, of which two are of the same type. The synaptic weights are arranged to establish and maintain a balance between excitation and inhibition in case of a constant external drive. Each subnetwork is randomly connected, where all neurons belonging to a particular population have the same in-degree and the same out-degree. Neurons in different subnetworks are also randomly connected with the same probability; however, depending on the type of the pre-synaptic neuron, the synaptic weight is scaled by a factor. We observed that for a certain range of the “within” versus “between” connection weights (bifurcation parameter), the network activation spontaneously switches between the two sub-networks of the same type. This kind of dynamics has been termed “winnerless competition”, which also has a random component here. In our model, this phenomenon is well described by a set of coupled stochastic differential equations of Lotka-Volterra type that imply a competition between the subnetworks. The associated mean-field model shows the same dynamical behavior as observed in simulations of large networks comprising thousands of spiking neurons. The deterministic phase portrait is characterized by two attractors and a saddle node, its stochastic component is essentially given by the multiplicative inherent noise of the system. We find that the dwell time distribution of the active states is exponential, indicating that the noise drives the system randomly from one attractor to the other. A similar model for a larger number of populations might suggest a general approach to study the dynamics of interacting populations of spiking networks. PMID:26407178
Competition in a Social Structure
NASA Astrophysics Data System (ADS)
Legara, Erika Fille; Longjas, Anthony; Batac, Rene
Complex adaptive agents develop strategies in the presence of competition. In modern human societies, there is an inherent sense of locality when describing inter-agent dynamics because of its network structure. One then wonders whether the traditional advertising schemes that are globally publicized and target random individuals are as effective in attracting a larger portion of the population as those that take advantage of local neighborhoods, such as "word-of-mouth" marketing schemes. Here, we demonstrate using a differential equation model that schemes targeting local cliques within the network are more successful at gaining a larger share of the population than those that target users randomly at a global scale (e.g., television commercials, print ads, etc.). This suggests that success in the competition is dependent not only on the number of individuals in the population but also on how they are connected in the network. We further show that the model is general in nature by considering examples of competition dynamics, particularly those of business competition and language death.
Application of random effects to the study of resource selection by animals
Gillies, C.S.; Hebblewhite, M.; Nielsen, S.E.; Krawchuk, M.A.; Aldridge, Cameron L.; Frair, J.L.; Saher, D.J.; Stevens, C.E.; Jerde, C.L.
2006-01-01
1. Resource selection estimated by logistic regression is used increasingly in studies to identify critical resources for animal populations and to predict species occurrence.2. Most frequently, individual animals are monitored and pooled to estimate population-level effects without regard to group or individual-level variation. Pooling assumes that both observations and their errors are independent, and resource selection is constant given individual variation in resource availability.3. Although researchers have identified ways to minimize autocorrelation, variation between individuals caused by differences in selection or available resources, including functional responses in resource selection, have not been well addressed.4. Here we review random-effects models and their application to resource selection modelling to overcome these common limitations. We present a simple case study of an analysis of resource selection by grizzly bears in the foothills of the Canadian Rocky Mountains with and without random effects.5. Both categorical and continuous variables in the grizzly bear model differed in interpretation, both in statistical significance and coefficient sign, depending on how a random effect was included. We used a simulation approach to clarify the application of random effects under three common situations for telemetry studies: (a) discrepancies in sample sizes among individuals; (b) differences among individuals in selection where availability is constant; and (c) differences in availability with and without a functional response in resource selection.6. We found that random intercepts accounted for unbalanced sample designs, and models with random intercepts and coefficients improved model fit given the variation in selection among individuals and functional responses in selection. Our empirical example and simulations demonstrate how including random effects in resource selection models can aid interpretation and address difficult assumptions limiting their generality. This approach will allow researchers to appropriately estimate marginal (population) and conditional (individual) responses, and account for complex grouping, unbalanced sample designs and autocorrelation.
Application of random effects to the study of resource selection by animals.
Gillies, Cameron S; Hebblewhite, Mark; Nielsen, Scott E; Krawchuk, Meg A; Aldridge, Cameron L; Frair, Jacqueline L; Saher, D Joanne; Stevens, Cameron E; Jerde, Christopher L
2006-07-01
1. Resource selection estimated by logistic regression is used increasingly in studies to identify critical resources for animal populations and to predict species occurrence. 2. Most frequently, individual animals are monitored and pooled to estimate population-level effects without regard to group or individual-level variation. Pooling assumes that both observations and their errors are independent, and resource selection is constant given individual variation in resource availability. 3. Although researchers have identified ways to minimize autocorrelation, variation between individuals caused by differences in selection or available resources, including functional responses in resource selection, have not been well addressed. 4. Here we review random-effects models and their application to resource selection modelling to overcome these common limitations. We present a simple case study of an analysis of resource selection by grizzly bears in the foothills of the Canadian Rocky Mountains with and without random effects. 5. Both categorical and continuous variables in the grizzly bear model differed in interpretation, both in statistical significance and coefficient sign, depending on how a random effect was included. We used a simulation approach to clarify the application of random effects under three common situations for telemetry studies: (a) discrepancies in sample sizes among individuals; (b) differences among individuals in selection where availability is constant; and (c) differences in availability with and without a functional response in resource selection. 6. We found that random intercepts accounted for unbalanced sample designs, and models with random intercepts and coefficients improved model fit given the variation in selection among individuals and functional responses in selection. Our empirical example and simulations demonstrate how including random effects in resource selection models can aid interpretation and address difficult assumptions limiting their generality. This approach will allow researchers to appropriately estimate marginal (population) and conditional (individual) responses, and account for complex grouping, unbalanced sample designs and autocorrelation.
Depression Care for Low-Income, Minority, Safety Net Clinic Populations with Comorbid Illness
ERIC Educational Resources Information Center
Ell, Kathleen; Lee, Pey-Jiuan; Xie, Bin
2010-01-01
Objective: Increasingly, mental health care is provided within the general health care sector. Accompanying this significant change is the demand for evidence-based as well as cost-effective or cost-neutral care models. Method: The authors present a pooled analysis of three large randomized clinical trials in which social workers provide…
Biological system interactions.
Adomian, G; Adomian, G E; Bellman, R E
1984-01-01
Mathematical modeling of cellular population growth, interconnected subsystems of the body, blood flow, and numerous other complex biological systems problems involves nonlinearities and generally randomness as well. Such problems have been dealt with by mathematical methods often changing the actual model to make it tractable. The method presented in this paper (and referenced works) allows much more physically realistic solutions. PMID:6585837
Suicide in the Army National Guard: An Empirical Inquiry
ERIC Educational Resources Information Center
Griffith, James
2012-01-01
Since 2004, suicides in the U.S. military have risen, most notably in the Army National Guard (ARNG). Data used in this study were obtained for suicides occurring from 2007 to 2010 and for a random sample of nonsuicides from the general ARNG population. Of the military-related variables considered, a few showed relationships to suicide. Rather,…
Effects of Self-Efficacy on Social Entrepreneurship in Education: A Correlational Research
ERIC Educational Resources Information Center
Konakll, Tugba
2015-01-01
The aim of this research is to determine the effects of pre-service teachers' self-efficacy on their social entrepreneurship characteristics. The population of this study consisted of 220 randomly selected pre-service teachers in Kocaeli University Faculty of Education in Turkey. General Self Efficacy Scale-Turkish Form and Pre-service Teachers'…
Hanrahan, Nancy P.; Wu, Evan; Kelly, Deena; Aiken, Linda H.; Blank, Michael B.
2011-01-01
Individuals with serious mental illness have greater risk for contracting HIV, multiple morbidities, and die 25 years younger than the general population. This high need and high cost subgroup face unique barriers to accessing required health care in the current health care system. The effectiveness of an advanced practice nurse model of care management was assessed in a four-year random controlled trial. Results are reported in this paper. In a four-year random controlled trial, a total of 238 community-dwelling individuals with HIV and serious mental illness (SMI) were randomly assigned to an intervention group (n=128) or to a control group (n=110). Over 12 months, the intervention group received care management from advanced practice psychiatric nurse, and the control group received usual care. The intervention group showed significant improvement in depression (P=.012) and the physical component of health-related quality of life (P=.03) from baseline to 12 months. The advanced practice psychiatric nurse intervention is a model of care that holds promise for a higher quality of care and outcomes for this vulnerable population. PMID:21935499
[The general survey for chondromalacia of 2,743 Chinese population].
Guo, K; Ye, Q; Zeng, X; Lin, J; Wu, Z
1998-06-01
To evaluate the distribution of chondromalacia patella in Chinese population. A random cluster sampling survey was performed covering 2,743 subjects varied in age, sex and occupation in 1995. The prevalence rate is 36.2%. The occurrence in women was higher than that in men (P < 0.01), while in the age group, 30 to 39 years was the highest being 55.8%. The prevalence rate in soldier being 47.5% was the highest among varied occupations. Our study is the first survey to be performed in a large number of Chinese population. This investigation may reflect the prevalence rate of chondromalacia patella in China.
Development of Activity and Participation Norms among General Adult Populations in Taiwan.
Yen, Chia-Feng; Chiu, Tzu-Ying; Liou, Tsan-Hon; Chi, Wen-Chou; Liao, Hua-Fang; Liang, Chung-Chao; Escorpizo, Reuben
2017-06-06
Based on the International Classification of Functioning, Disability, and Health (ICF) and the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0), The Functioning Disability Evaluation Scale-Adult version (FUNDES-Adult) began development in 2011. The FUNDES-Adult was designed to assess the difficulty level of an individual's activities and participation in daily life. There is a lack of research regarding the profile of activity and participation for the general adult population. The purposes of this study were to establish activity and participation norms for the general adult population in Taiwan and to describe, discuss, and compare the activity and participation profile with other population. A population-based survey was administered in 2013 using a computer-assisted telephone interviewing system (CATI system). Using probability proportional to size (PPS) sampling and systematic sampling with random digit dialing (RDD), 1500 adults from Taiwan's general population were selected to participate in the survey. The FUNDES-Adult with six domains and two dimensions (performance and capability) was used to obtain data on activities and participation levels. A higher domain score indicated higher participation restriction. Approximately 50% of the respondents were male, and the average age of the respondents was 45.23 years. There were no significant differences in the demographic features between the sample and the population. Among the six domains, the self-care domain score was the lowest (least restriction) and the participation domain score was the highest (most restriction). Approximately 90% of the sample scored were less than 15, and only 0.1% scored more than 80. This is the first cross-national population-based survey to assess norms of activity and participation relevant to the general population of Taiwan. As such, the results of this survey can be used as a reference for comparing the activity and participation (AP) functioning of other countries and subgroups.
Pérez-Del-Olmo, A; Montero, F E; Fernández, M; Barrett, J; Raga, J A; Kostadinova, A
2010-10-01
We address the effect of spatial scale and temporal variation on model generality when forming predictive models for fish assignment using a new data mining approach, Random Forests (RF), to variable biological markers (parasite community data). Models were implemented for a fish host-parasite system sampled along the Mediterranean and Atlantic coasts of Spain and were validated using independent datasets. We considered 2 basic classification problems in evaluating the importance of variations in parasite infracommunities for assignment of individual fish to their populations of origin: multiclass (2-5 population models, using 2 seasonal replicates from each of the populations) and 2-class task (using 4 seasonal replicates from 1 Atlantic and 1 Mediterranean population each). The main results are that (i) RF are well suited for multiclass population assignment using parasite communities in non-migratory fish; (ii) RF provide an efficient means for model cross-validation on the baseline data and this allows sample size limitations in parasite tag studies to be tackled effectively; (iii) the performance of RF is dependent on the complexity and spatial extent/configuration of the problem; and (iv) the development of predictive models is strongly influenced by seasonal change and this stresses the importance of both temporal replication and model validation in parasite tagging studies.
Analytical connection between thresholds and immunization strategies of SIS model in random networks
NASA Astrophysics Data System (ADS)
Zhou, Ming-Yang; Xiong, Wen-Man; Liao, Hao; Wang, Tong; Wei, Zong-Wen; Fu, Zhong-Qian
2018-05-01
Devising effective strategies for hindering the propagation of viruses and protecting the population against epidemics is critical for public security and health. Despite a number of studies based on the susceptible-infected-susceptible (SIS) model devoted to this topic, we still lack a general framework to compare different immunization strategies in completely random networks. Here, we address this problem by suggesting a novel method based on heterogeneous mean-field theory for the SIS model. Our method builds the relationship between the thresholds and different immunization strategies in completely random networks. Besides, we provide an analytical argument that the targeted large-degree strategy achieves the best performance in random networks with arbitrary degree distribution. Moreover, the experimental results demonstrate the effectiveness of the proposed method in both artificial and real-world networks.
Allen, Benjamin; Sample, Christine; Dementieva, Yulia; Medeiros, Ruben C.; Paoletti, Christopher; Nowak, Martin A.
2015-01-01
Over time, a population acquires neutral genetic substitutions as a consequence of random drift. A famous result in population genetics asserts that the rate, K, at which these substitutions accumulate in the population coincides with the mutation rate, u, at which they arise in individuals: K = u. This identity enables genetic sequence data to be used as a “molecular clock” to estimate the timing of evolutionary events. While the molecular clock is known to be perturbed by selection, it is thought that K = u holds very generally for neutral evolution. Here we show that asymmetric spatial population structure can alter the molecular clock rate for neutral mutations, leading to either Ku. Our results apply to a general class of haploid, asexually reproducing, spatially structured populations. Deviations from K = u occur because mutations arise unequally at different sites and have different probabilities of fixation depending on where they arise. If birth rates are uniform across sites, then K ≤ u. In general, K can take any value between 0 and Nu. Our model can be applied to a variety of population structures. In one example, we investigate the accumulation of genetic mutations in the small intestine. In another application, we analyze over 900 Twitter networks to study the effect of network topology on the fixation of neutral innovations in social evolution. PMID:25719560
Allen, Benjamin; Sample, Christine; Dementieva, Yulia; Medeiros, Ruben C; Paoletti, Christopher; Nowak, Martin A
2015-02-01
Over time, a population acquires neutral genetic substitutions as a consequence of random drift. A famous result in population genetics asserts that the rate, K, at which these substitutions accumulate in the population coincides with the mutation rate, u, at which they arise in individuals: K = u. This identity enables genetic sequence data to be used as a "molecular clock" to estimate the timing of evolutionary events. While the molecular clock is known to be perturbed by selection, it is thought that K = u holds very generally for neutral evolution. Here we show that asymmetric spatial population structure can alter the molecular clock rate for neutral mutations, leading to either Ku. Our results apply to a general class of haploid, asexually reproducing, spatially structured populations. Deviations from K = u occur because mutations arise unequally at different sites and have different probabilities of fixation depending on where they arise. If birth rates are uniform across sites, then K ≤ u. In general, K can take any value between 0 and Nu. Our model can be applied to a variety of population structures. In one example, we investigate the accumulation of genetic mutations in the small intestine. In another application, we analyze over 900 Twitter networks to study the effect of network topology on the fixation of neutral innovations in social evolution.
Prevalence of contact allergy in the general population in different European regions.
Diepgen, T L; Ofenloch, R F; Bruze, M; Bertuccio, P; Cazzaniga, S; Coenraads, P-J; Elsner, P; Goncalo, M; Svensson, Å; Naldi, L
2016-02-01
Population-based studies about contact allergy are scarce. To obtain reliable estimates of the prevalence of contact allergy in the general population in Europe. A cross-sectional study of a random sample from the general population, aged 18-74 years, in five different European countries (Sweden, the Netherlands, Germany, Italy and Portugal). In total, 12 377 subjects were interviewed and a random sample (n = 3119) patch tested to TRUE Test panels 1-3 and Fragrance Mix (FM) II, hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) and sesquiterpene lactone mix. A positive patch test reaction is considered as contact allergy. In total, 27·0% [95% confidence interval (CI) 25·5-28·5] had at least one positive reaction to an allergen of the European baseline series, with a significantly higher prevalence in women than in men. The highest age-standardized prevalences (≥ 1%) were found for nickel (14·5%, 95% CI 13·2-15·8), thiomersal (5·0%, 95% CI 4·2-5·8), cobalt (2·2%, 95% CI 1·7-2·7), FM II (1·9%, 95% CI 1·5-2·5), FM I (1·8%, 95% CI 1·4-2·3), HICC (1·4%, 95% CI 1·0-1·9), p-tert-butylphenol formaldehyde resin (1·3%, 95% CI 0·9-1·7) and para-phenylenediamine (1·0%, 95% CI 0·6-1·3). Only nickel and thiomersal showed a statistically significantly different prevalence for contact allergy among the different European populations. Subjects reporting contact dermatitis in their lifetime (age-standardized prevalence 15·1%, 95% CI 13·8-16·3) had an increased risk for contact allergy (odds ratio 1·9, 95% CI 1·5-2·5). The risk of having a contact allergy was not increased in those with atopic dermatitis (prevalence 7·6%, 95% CI 6·7-8·6; odds ratio 1·0, 95% CI 0·7-1·4). Contact allergy to at least one allergen of the European baseline series was diagnosed in more than one-quarter of the general European population. Therefore measures to improve the primary prevention of contact allergy have to be enforced. © 2015 British Association of Dermatologists.
Popova, Svetlana; Lange, Shannon; Probst, Charlotte; Parunashvili, Nino; Rehm, Jürgen
2017-01-01
Prenatal alcohol exposure may cause a number of health complications for the mother and developing fetus, including Fetal Alcohol Spectrum Disorders (FASD). This study aimed to estimate the pooled prevalence of i) alcohol use (any amount) and binge drinking (4 or more standard drinks on a single occasion) during pregnancy, and ii) Fetal Alcohol Syndrome (FAS) and FASD among the general and Aboriginal populations in Canada and the United States, based on the available literature. Comprehensive systematic literature searches and meta-analyses, assuming a random-effects model, were conducted. It was revealed that about 10% and 15% of pregnant women in the general population consume alcohol in Canada and the United States, respectively, and that about 3% of women engage in binge drinking during pregnancy in both countries. However, the prevalence of alcohol use during pregnancy in the Aboriginal populations of the United States and Canada were found to be approximately 3-4 times higher, respectively, compared to the general population. Even more alarmingly, it was estimated that approximately one in five women in the Aboriginal populations in both countries engage in binge drinking during pregnancy. Further, among the general population of Canada, the pooled prevalence was estimated to be about 1 per 1000 for FAS and 5 per 1000 for FASD. However, compared to the general population, the prevalence of FAS and FASD among the Aboriginal population in Canada was estimated to be 38 times and 16 times higher, respectively. With respect to the United States, the pooled prevalence of FAS and FASD was estimated to be about 2 per 1000 and 15 per 1,000, respectively, among the general population, and 4 per 1000 and 10 per 1,000, respectively, among the Aboriginal population. The FAS and FASD pooled prevalence estimates presented here should be used with caution due to the limited number of existing studies and their methodological limitations. Based on the results of the current study, it is evident that there is an urgent need for implementing more effective national prevention and surveillance strategies to monitor and lower the prevalence of alcohol consumption during pregnancy and FASD. Copyright © 2016 The Authors. Published by Elsevier Masson SAS.. All rights reserved.
Hsu, Jer-Hwa; Chien, I-Chia; Lin, Ching-Heng
2017-10-01
We conducted this nationwide study to examine the prevalence and incidence of chronic obstructive pulmonary disease (COPD) among patients with bipolar disorder in Taiwan. We used a random sample of 766,427 subjects who were aged ≥18 years in 2005. Patients with at least one primary diagnosis of bipolar disorder were identified. Study participants with one primary or secondary diagnosis of COPD for either ambulatory or inpatient care were also identified. We compared the prevalence of COPD in patients with bipolar disorder and the general population in 2005. In addition, we further investigated this cohort from 2006 to 2010 to detect incident cases of COPD in patients with bipolar disorder compared with the general population. The factors associated with COPD among patients with bipolar disorder were also analyzed. The prevalence of COPD in patients with bipolar disorder was higher than in the general population in 2005 (5.68% vs. 2.88%, odds ratio 2.03; 95% confidence interval, 1.53-2.67). The average annual incidence of COPD in patients with bipolar disorder was also higher than in the general population (2.03% vs. 1.03%, risk ratio 1.94; 95% confidence interval, 1.65-2.29) from 2006 to 2010. Some risk factors for COPD such as substance use, obesity, or lifestyle pattern were not available in this study. Patients with bipolar disorder had a higher prevalence and incidence of COPD compared with the general population. Higher prevalence of COPD among bipolar patients was associated with increased age, males, hypertension, and second-generation antidepressant use. Copyright © 2017 Elsevier B.V. All rights reserved.
Hörnquist, Lina; Rickardsson, Jenny; Lannering, Birgitta; Gustafsson, Göran; Boman, Krister K.
2015-01-01
Background Survivors of pediatric CNS tumors are at risk for persistent tumor/treatment-related morbidity, physical disability and social consequences that may alter self-perception, vital for self-identity, mental health and quality of survival. We studied the long-term impact of childhood CNS tumors and their treatment on the self-perception of adult survivors and compared outcomes with those of the general population. Methods The cohort included 697 Swedish survivors diagnosed with a primary CNS tumor during 1982–2001. Comparison data were randomly collected from a stratified general population sample. Survivors and general population individuals were compared as regards self-perception in 5 domains: body image, sports/physical activities, peers, work, and family, and with a global self-esteem index. Within the survivor group, determinants of impact on self-perception were identified. Results The final analyzed sample included 528 survivors, 75.8% of the entire national cohort. The control sample consisted of 995, 41% of 2500 addressed. Survivors had significantly poorer self-perception outcomes in domains of peers, work, body image, and sports/physical activities, and in the global self-perception measure, compared with those of the general population (all P < .001). Within the survivor group, female gender and persistent visible physical sequelae predicted poorer outcomes in several of the studied domains. Tumor type and a history of cranial radiation therapy were associated with outcomes. Conclusion An altered self-perception is a potential late effect in adult survivors of pediatric CNS tumors. Self-perception and self-esteem are significant elements of identity, mental health and quality of survival. Therefore, care and psychosocial follow-up of survivors should include measures for identifying disturbances and for assessing the need for psychosocial intervention. PMID:25332406
Characteristics of a random sample of emergency food program users in New York: II. Soup kitchens.
Bowering, J; Clancy, K L; Poppendieck, J
1991-01-01
A random sample of soup kitchen clients in New York City was studied and specific comparisons made on various parameters including homelessness. Compared with the general population of low income persons, soup kitchen users were overwhelmingly male, disproportionately African-American, and more likely to live alone. The homeless (41 percent of the sample) were less likely to receive food stamps or free food, or to use food pantries. Fewer of them received Medicaid or had health insurance. Forty-seven percent had no income in contrast to 29 percent of the total sample. PMID:2053673
Quantifying the dose-response of walking in reducing coronary heart disease risk: meta-analysis.
Zheng, Henry; Orsini, Nicola; Amin, Janaki; Wolk, Alicja; Nguyen, Van Thi Thuy; Ehrlich, Fred
2009-01-01
The evidence for the efficacy of walking in reducing the risk of and preventing coronary heart disease (CHD) is not completely understood. This meta-analysis aimed to quantify the dose-response relationship between walking and CHD risk reduction for both men and women in the general population. Studies on walking and CHD primary prevention between 1954 and 2007 were identified through Medline, SportDiscus and the Cochrane Database of Systematic Reviews. Random-effect meta-regression models were used to pool the relative risks from individual studies. A total of 11 prospective cohort studies and one randomized control trial study met the inclusion criteria, with 295,177 participants free of CHD at baseline and 7,094 cases at follow-up. The meta-analysis indicated that an increment of approximately 30 min of normal walking a day for 5 days a week was associated with 19% CHD risk reduction (95% CI = 14-23%; P-heterogeneity = 0.56; I (2) = 0%). We found no evidence of heterogeneity between subgroups of studies defined by gender (P = 0.67); age of the study population (P = 0.52); or follow-up duration (P = 0.77). The meta-analysis showed that the risk for developing CHD decreases as walking dose increases. Walking should be prescribed as an evidence-based effective exercise modality for CHD prevention in the general population.
Griffioen, Brecht T; van der Vegt, Anna A; de Groot, Izaäk W; de Jongh, Ad
2017-01-01
Although low self-esteem has been found to be an important factor in the development and maintenance of psychopathology, surprisingly little is known about its treatment. This study investigated the effectiveness of Eye Movement Desensitization and Reprocessing (EMDR) therapy and Cognitive Behavioural Therapy (CBT), regarding their capacities in enhancing self-esteem in a general psychiatric secondary health care population. A randomized controlled trial with two parallel groups was used. Participants were randomly allocated to either 10 weekly sessions of EMDR ( n = 15) or CBT ( n = 15). They were assessed pre-treatment, after each session, post treatment and at 3 months follow-up on self-esteem (Rosenberg Self-esteem Scale and Credibility of Core Beliefs), psychological symptoms (Brief Symptom Inventory), social anxiety, and social interaction (Inventory of Interpersonal Situations) (IIS). The data were analyzed using repeated measures ANOVA for the complete cases ( n = 19) and intention-to-treat ( n = 30) to examine differences over time and between conditions. Both groups, EMDR as well as CBT, showed significant improvements on self-esteem, increasing two standard deviations on the main parameter (RSES). Furthermore, the results showed significant reductions in general psychiatric symptoms. The effects were maintained at 3 months follow-up. No between-group differences could be detected. Although the small sample requires to exercise caution in the interpretation of the findings, the results suggest that, when offering an adequate number of sessions, both EMDR and CBT have the potential to be effective treatments for patients with low self-esteem and a wide range of comorbid psychiatric conditions. This study was registered at www.trialregister.nl with identifier NTR4611.
Griffioen, Brecht T.; van der Vegt, Anna A.; de Groot, Izaäk W.; de Jongh, Ad
2017-01-01
Although low self-esteem has been found to be an important factor in the development and maintenance of psychopathology, surprisingly little is known about its treatment. This study investigated the effectiveness of Eye Movement Desensitization and Reprocessing (EMDR) therapy and Cognitive Behavioural Therapy (CBT), regarding their capacities in enhancing self-esteem in a general psychiatric secondary health care population. A randomized controlled trial with two parallel groups was used. Participants were randomly allocated to either 10 weekly sessions of EMDR (n = 15) or CBT (n = 15). They were assessed pre-treatment, after each session, post treatment and at 3 months follow-up on self-esteem (Rosenberg Self-esteem Scale and Credibility of Core Beliefs), psychological symptoms (Brief Symptom Inventory), social anxiety, and social interaction (Inventory of Interpersonal Situations) (IIS). The data were analyzed using repeated measures ANOVA for the complete cases (n = 19) and intention-to-treat (n = 30) to examine differences over time and between conditions. Both groups, EMDR as well as CBT, showed significant improvements on self-esteem, increasing two standard deviations on the main parameter (RSES). Furthermore, the results showed significant reductions in general psychiatric symptoms. The effects were maintained at 3 months follow-up. No between-group differences could be detected. Although the small sample requires to exercise caution in the interpretation of the findings, the results suggest that, when offering an adequate number of sessions, both EMDR and CBT have the potential to be effective treatments for patients with low self-esteem and a wide range of comorbid psychiatric conditions. This study was registered at www.trialregister.nl with identifier NTR4611. PMID:29167649
USDA-ARS?s Scientific Manuscript database
RMBUP-C4 (Random Mated Barbadense Upland Population Cycle 4) (Reg. No. GP_____: PI______) is a unique random mated germplasm population of Upland cotton (Gossypium hirsutum L.) which has introgression of G. barbadense L. alleles. This population involved five cycles of random mating beginning ...
Pengpid, Supa; Peltzer, Karl; Puckpinyo, Apa; Tiraphat, Sariyamon; Viripiromgool, Somchai; Apidechkul, Tawatchai; Sathirapanya, Chutarat; Leethongdee, Songkramchai; Chompikul, Jiraporn; Mongkolchati, Aroonsri
2016-08-02
The aim of this study was to assess tuberculosis (TB) knowledge, attitudes, and practices in both the general population and risk groups in Thailand. In a cross-sectional survey, a general population (n = 3,074) and family members of a TB patient (n = 559) were randomly selected, using stratified multistage sampling, and interviewed. The average TB knowledge score was 5.7 (maximum = 10) in the Thai and 5.1 in the migrant and ethnic minorities general populations, 6.3 in Thais with a family member with TB, and 5.4 in migrants and ethnic minorities with a family member with TB. In multivariate linear regression among the Thai general population, higher education, higher income, and knowing a person from the community with TB were all significantly associated with level of TB knowledge. Across the different study populations, 18.6% indicated that they had undergone a TB screening test. Multivariate logistic regression found that older age, lower education, being a migrant or belonging to an ethnic minority group, residing in an area supported by the Global Fund, better TB knowledge, having a family member with TB, and knowing other people in the community with TB was associated having been screened for TB. This study revealed deficiencies in the public health knowledge about TB, particularly among migrants and ethnic minorities in Thailand. Sociodemographic factors should be considered when designing communication strategies and TB prevention and control interventions.
Churchill, Jennifer D; Novroski, Nicole M M; King, Jonathan L; Seah, Lay Hong; Budowle, Bruce
2017-09-01
The MiSeq FGx Forensic Genomics System (Illumina) enables amplification and massively parallel sequencing of 59 STRs, 94 identity informative SNPs, 54 ancestry informative SNPs, and 24 phenotypic informative SNPs. Allele frequency and population statistics data were generated for the 172 SNP loci included in this panel on four major population groups (Chinese, African Americans, US Caucasians, and Southwest Hispanics). Single-locus and combined random match probability values were generated for the identity informative SNPs. The average combined STR and identity informative SNP random match probabilities (assuming independence) across all four populations were 1.75E-67 and 2.30E-71 with length-based and sequence-based STR alleles, respectively. Ancestry and phenotype predictions were obtained using the ForenSeq™ Universal Analysis System (UAS; Illumina) based on the ancestry informative and phenotype informative SNP profiles generated for each sample. Additionally, performance metrics, including profile completeness, read depth, relative locus performance, and allele coverage ratios, were evaluated and detailed for the 725 samples included in this study. While some genetic markers included in this panel performed notably better than others, performance across populations was generally consistent. The performance and population data included in this study support that accurate and reliable profiles were generated and provide valuable background information for laboratories considering internal validation studies and implementation. Copyright © 2017 Elsevier B.V. All rights reserved.
Prevalence of obesity in a rural Asian Indian (Bangladeshi) population and its determinants.
Siddiquee, Tasnima; Bhowmik, Bishwajit; Da Vale Moreira, Nayla Cristina; Mujumder, Anindita; Mahtab, Hajera; Khan, A K Azad; Hussain, Akhtar
2015-09-04
Obesity has reached epidemic proportions worldwide including Bangladesh. To assess the prevalence and associated factors of general and central obesity in a rural Bangladeshi population based on newly proposed cut off level for Asian population. 2293 subjects aged ≥ 20 years from rural Bangladesh were randomly recruited to participate in a population-based, cross sectional survey, conducted in 2009. Both socio-demographic and anthropometric measurements were recorded. Age adjusted data for anthropometric indices were examined. The age standardized prevalence of overweight (BMI 23-24.9 kg/m(2)) and obesity (BMI ≥ 25 kg/m(2)) were 17.7 (95% confidence interval (CI): 16.1, 19.2%) and 26.2% (95% CI: 24.4, 27.9%), respectively. The age standardized prevalence of central obesity based on WC (M ≥ 90 & F ≥ 80 cm) and WHR (M ≥ 0.90 & F ≥ 0.80) were 39.8% (95% CI: 37.9, 41.7%) and 71.6% (95% CI: 69.8, 73.4%) respectively. The result shows that prevalence of central obesity was more in female than male. Study shows middle age, medium and high socioeconomic status (SES), low education levels, physical inactivity, high consumption of carbohydrate, protein and fat, were significant risk indicators for general and central obesity. Smoking was shown as protective factor for both general and central obesity. In rural Bangladeshi population, the prevalence of both general and central obesity was high among both sexes with the use of newly proposed cut off points for Asian population. Gender, diet, physical activity, education levels and SES were associated with the increase prevalence of obesity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, K. S.; Nakae, L. F.; Prasad, M. K.
Here, we solve a simple theoretical model of time evolving fission chains due to Feynman that generalizes and asymptotically approaches the point model theory. The point model theory has been used to analyze thermal neutron counting data. This extension of the theory underlies fast counting data for both neutrons and gamma rays from metal systems. Fast neutron and gamma-ray counting is now possible using liquid scintillator arrays with nanosecond time resolution. For individual fission chains, the differential equations describing three correlated probability distributions are solved: the time-dependent internal neutron population, accumulation of fissions in time, and accumulation of leaked neutronsmore » in time. Explicit analytic formulas are given for correlated moments of the time evolving chain populations. The equations for random time gate fast neutron and gamma-ray counting distributions, due to randomly initiated chains, are presented. Correlated moment equations are given for both random time gate and triggered time gate counting. There are explicit formulas for all correlated moments are given up to triple order, for all combinations of correlated fast neutrons and gamma rays. The nonlinear differential equations for probabilities for time dependent fission chain populations have a remarkably simple Monte Carlo realization. A Monte Carlo code was developed for this theory and is shown to statistically realize the solutions to the fission chain theory probability distributions. Combined with random initiation of chains and detection of external quanta, the Monte Carlo code generates time tagged data for neutron and gamma-ray counting and from these data the counting distributions.« less
Using Propensity Score Matching Methods to Improve Generalization from Randomized Experiments
ERIC Educational Resources Information Center
Tipton, Elizabeth
2011-01-01
The main result of an experiment is typically an estimate of the average treatment effect (ATE) and its standard error. In most experiments, the number of covariates that may be moderators is large. One way this issue is typically skirted is by interpreting the ATE as the average effect for "some" population. Cornfield and Tukey (1956)…
ERIC Educational Resources Information Center
Dunning, Darren L.; Holmes, Joni; Gathercole, Susan E.
2013-01-01
Children with low working memory typically make poor educational progress, and it has been speculated that difficulties in meeting the heavy working memory demands of the classroom may be a contributory factor. Intensive working memory training has been shown to boost performance on untrained memory tasks in a variety of populations. This first…
ERIC Educational Resources Information Center
Skovgaard, Anne Mette; Houmann, Tine; Christiansen, Eva; Landorph, Susanne; Jorgensen, Torben; Olsen, E. M.; Heering, K.; Kaas-Nielsen, S.; Samberg, V.; Lichtenberg, A.
2007-01-01
Background: The Copenhagen Child Cohort, CCC 2000, was established to investigate developmental psychopathology prospectively from birth in a general population. Methods: A random sample of 211 children from the CCC 2000 was investigated when the children were 1 1/2 years of age. The prevalence and associates of mental health problems and…
ERIC Educational Resources Information Center
Legleye, Stéphane; Charrance, Géraldine; Razafindratsima, Nicolas; Bajos, Nathalie; Bohet, Aline; Moreau, Caroline
2018-01-01
Background: Reliability of nonprobability online volunteer panels for epidemiological purposes has rarely been studied. Objectives: To assess the quality of a questionnaire on sexual and reproductive health (SRH) administered in a nonprobability Web panel and in a random telephone survey (n = 8,992; n = 8,437, age 16-49 years). Especially, we were…
ERIC Educational Resources Information Center
Gavin, Amanda; Roche, Bryan; Ruiz, Maria R.; Hogan, Maria; O'Reilly, Anthony
2012-01-01
The current study assessed the sexual categorization of children among a random sample of adults from the general population. Twenty-seven males and 27 females (N = 54) were exposed to a categorization task that assessed their ability to discriminate adult- from child-related words and sexual from non-sexual words. Then, in a modified Implicit…
First passage properties of a generalized Pólya urn
NASA Astrophysics Data System (ADS)
Kearney, Michael J.; Martin, Richard J.
2016-12-01
A generalized two-component Pólya urn process, parameterized by a variable α , is studied in terms of the likelihood that due to fluctuations the initially smaller population in a scenario of competing population growth eventually becomes the larger, or is the larger after a certain passage of time. By casting the problem as an inhomogeneous directed random walk we quantify this role-reversal phenomenon through the first passage probability that equality in size is first reached at a given time, and the related exit probability that equality in size is reached no later than a given time. Using an embedding technique, exact results are obtained which complement existing results and provide new insights into behavioural changes (akin to phase transitions) which occur at defined values of α .
The non-equilibrium allele frequency spectrum in a Poisson random field framework.
Kaj, Ingemar; Mugal, Carina F
2016-10-01
In population genetic studies, the allele frequency spectrum (AFS) efficiently summarizes genome-wide polymorphism data and shapes a variety of allele frequency-based summary statistics. While existing theory typically features equilibrium conditions, emerging methodology requires an analytical understanding of the build-up of the allele frequencies over time. In this work, we use the framework of Poisson random fields to derive new representations of the non-equilibrium AFS for the case of a Wright-Fisher population model with selection. In our approach, the AFS is a scaling-limit of the expectation of a Poisson stochastic integral and the representation of the non-equilibrium AFS arises in terms of a fixation time probability distribution. The known duality between the Wright-Fisher diffusion process and a birth and death process generalizing Kingman's coalescent yields an additional representation. The results carry over to the setting of a random sample drawn from the population and provide the non-equilibrium behavior of sample statistics. Our findings are consistent with and extend a previous approach where the non-equilibrium AFS solves a partial differential forward equation with a non-traditional boundary condition. Moreover, we provide a bridge to previous coalescent-based work, and hence tie several frameworks together. Since frequency-based summary statistics are widely used in population genetics, for example, to identify candidate loci of adaptive evolution, to infer the demographic history of a population, or to improve our understanding of the underlying mechanics of speciation events, the presented results are potentially useful for a broad range of topics. Copyright © 2016 Elsevier Inc. All rights reserved.
Schwalger, Tilo; Deger, Moritz; Gerstner, Wulfram
2017-04-01
Neural population equations such as neural mass or field models are widely used to study brain activity on a large scale. However, the relation of these models to the properties of single neurons is unclear. Here we derive an equation for several interacting populations at the mesoscopic scale starting from a microscopic model of randomly connected generalized integrate-and-fire neuron models. Each population consists of 50-2000 neurons of the same type but different populations account for different neuron types. The stochastic population equations that we find reveal how spike-history effects in single-neuron dynamics such as refractoriness and adaptation interact with finite-size fluctuations on the population level. Efficient integration of the stochastic mesoscopic equations reproduces the statistical behavior of the population activities obtained from microscopic simulations of a full spiking neural network model. The theory describes nonlinear emergent dynamics such as finite-size-induced stochastic transitions in multistable networks and synchronization in balanced networks of excitatory and inhibitory neurons. The mesoscopic equations are employed to rapidly integrate a model of a cortical microcircuit consisting of eight neuron types, which allows us to predict spontaneous population activities as well as evoked responses to thalamic input. Our theory establishes a general framework for modeling finite-size neural population dynamics based on single cell and synapse parameters and offers an efficient approach to analyzing cortical circuits and computations.
Education in cardiopulmonary resuscitation in Russia: A systematic review of the available evidence
Birkun, Alexei; Glotov, Maksim
2017-01-01
BACKGROUND: To summarise and appraise cumulative published scientific evidence relevant to cardiopulmonary resuscitation (CPR) education in Russia. DATA RESOURCES: We searched Medline, Scopus, Science Direct and Russian Science Citation Index databases from December 1991 to December 2016 to identify studies pertaining to the field of CPR education that were carried out by Russian researchers and/or investigated the topic of interest for Russia/Russian population. Reference lists of eligible publications, contents pages of relevant Russian journals and Google Scholar were also searched. There was no limitation based on publication language or study design. RESULTS: Of 7 964 unique citations identified, 22 studies were included. All studies were published from 2009 to 2016, mainly in Russian. Only three studies were reported to be randomized controlled. Non-medical individuals constituted 17% of studied populations. Most of the studies aimed to assess effects of CPR educational interventions, generally suggesting positive influence of the training conducted. The studies were highly heterogeneous as for methodological approaches, structure and duration of educational interventions, evaluation methods and criteria being used. Methodological quality was generally poor, with >40% publications not passing quality screening and only 2 studies meeting the criteria of moderate high quality. CONCLUSION: The results suggest paucity, low population coverage, high thematic and methodological heterogeneity and low quality of the studies addressing CPR education, which were carried out in the Russian Federation. There is a critical need in conducting methodologically consistent, large-scale, randomized, controlled studies evaluating and comparing efficiency of educational interventions for teaching CPR in different population categories of Russia. PMID:29123601
Levene, Louis S; Baker, Richard; Walker, Nicola; Williams, Christopher; Wilson, Andrew; Bankart, John
2018-06-01
Increased relationship continuity in primary care is associated with better health outcomes, greater patient satisfaction, and fewer hospital admissions. Greater socioeconomic deprivation is associated with lower levels of continuity, as well as poorer health outcomes. To investigate whether deprivation scores predicted variations in the decline over time of patient-perceived relationship continuity of care, after adjustment for practice organisational and population factors. An observational study in 6243 primary care practices with more than one GP, in England, using a longitudinal multilevel linear model, 2012-2017 inclusive. Patient-perceived relationship continuity was calculated using two questions from the GP Patient Survey. The effect of deprivation on the linear slope of continuity over time was modelled, adjusting for nine confounding variables (practice population and organisational factors). Clustering of measurements within general practices was adjusted for by using a random intercepts and random slopes model. Descriptive statistics and univariable analyses were also undertaken. Relationship continuity declined by 27.5% between 2012 and 2017, and at all deprivation levels. Deprivation scores from 2012 did not predict variations in the decline of relationship continuity at practice level, after accounting for the effects of organisational and population confounding variables, which themselves did not predict, or weakly predicted with very small effect sizes, the decline of continuity. Cross-sectionally, continuity and deprivation were negatively correlated within each year. The decline in relationship continuity of care has been marked and widespread. Measures to maximise continuity will need to be feasible for individual practices with diverse population and organisational characteristics. © British Journal of General Practice 2018.
Emergence of cooperation with self-organized criticality
NASA Astrophysics Data System (ADS)
Park, Sangmin; Jeong, Hyeong-Chai
2012-02-01
Cooperation and self-organized criticality are two main keywords in current studies of evolution. We propose a generalized Bak-Sneppen model and provide a natural mechanism which accounts for both phenomena simultaneously. We use the prisoner's dilemma games to mimic the interactions among the members in the population. Each member is identified by its cooperation probability, and its fitness is given by the payoffs from neighbors. The least fit member with the minimum payoff is replaced by a new member with a random cooperation probability. When the neighbors of the least fit one are also replaced with a non-zero probability, a strong cooperation emerges. The Bak-Sneppen process builds a self-organized structure so that the cooperation can emerge even in the parameter region where a uniform or random population decreases the number of cooperators. The emergence of cooperation is due to the same dynamical correlation that leads to self-organized criticality in replacement activities.
Efficient mitigation strategies for epidemics in rural regions.
Scoglio, Caterina; Schumm, Walter; Schumm, Phillip; Easton, Todd; Roy Chowdhury, Sohini; Sydney, Ali; Youssef, Mina
2010-07-13
Containing an epidemic at its origin is the most desirable mitigation. Epidemics have often originated in rural areas, with rural communities among the first affected. Disease dynamics in rural regions have received limited attention, and results of general studies cannot be directly applied since population densities and human mobility factors are very different in rural regions from those in cities. We create a network model of a rural community in Kansas, USA, by collecting data on the contact patterns and computing rates of contact among a sampled population. We model the impact of different mitigation strategies detecting closely connected groups of people and frequently visited locations. Within those groups and locations, we compare the effectiveness of random and targeted vaccinations using a Susceptible-Exposed-Infected-Recovered compartmental model on the contact network. Our simulations show that the targeted vaccinations of only 10% of the sampled population reduced the size of the epidemic by 34.5%. Additionally, if 10% of the population visiting one of the most popular locations is randomly vaccinated, the epidemic size is reduced by 19%. Our results suggest a new implementation of a highly effective strategy for targeted vaccinations through the use of popular locations in rural communities.
Penedo, Frank J; Dahn, Jason R
2005-03-01
This review highlights recent work evaluating the relationship between exercise, physical activity and physical and mental health. Both cross-sectional and longitudinal studies, as well as randomized clinical trials, are included. Special attention is given to physical conditions, including obesity, cancer, cardiovascular disease and sexual dysfunction. Furthermore, studies relating physical activity to depression and other mood states are reviewed. The studies include diverse ethnic populations, including men and women, as well as several age groups (e.g. adolescents, middle-aged and older adults). Results of the studies continue to support a growing literature suggesting that exercise, physical activity and physical-activity interventions have beneficial effects across several physical and mental-health outcomes. Generally, participants engaging in regular physical activity display more desirable health outcomes across a variety of physical conditions. Similarly, participants in randomized clinical trials of physical-activity interventions show better health outcomes, including better general and health-related quality of life, better functional capacity and better mood states. The studies have several implications for clinical practice and research. Most work suggests that exercise and physical activity are associated with better quality of life and health outcomes. Therefore, assessment and promotion of exercise and physical activity may be beneficial in achieving desired benefits across several populations. Several limitations were noted, particularly in research involving randomized clinical trials. These trials tend to involve limited sample sizes with short follow-up periods, thus limiting the clinical implications of the benefits associated with physical activity.
Design of the Blood Pressure Goals in Dialysis pilot study.
Gul, Ambreen; Miskulin, Dana; Gassman, Jennifer; Harford, Antonia; Horowitz, Bruce; Chen, Joline; Paine, Susan; Bedrick, Edward; Kusek, John W; Unruh, Mark; Zager, Philip
2014-02-01
Cardiovascular disease (CVD) is markedly increased among hemodialysis (HD) patients. Optimizing blood pressure (BP) among HD patients may present an important opportunity to reduce the disparity in CVD rates between HD patients and the general population. The optimal target predialysis systolic BP (SBP) among HD patients is unknown. Current international guidelines, calling for a predialysis SBP < 140 mm Hg, are based on the opinion and extrapolation from the general population. Existing randomized controlled trials (RCTs) were small and did not include prespecified BP targets. The authors described the design of the Blood Pressure in Dialysis (BID) Study, a pilot, multicenter RCT where HD patients are randomized to either a target-standardized predialysis SBP of 110 to 140 mm Hg or 155 to 165 mm Hg. This is the first study to randomize HD patients to 2 different SBP targets. Primary outcomes are feasibility and safety. Feasibility parameters include recruitment and retention rates, adherence with prescribed BP measurements and achievement and maintenance of selected BP targets. Safety parameters include rates of hypotension and other adverse and serious adverse events. The authors obtained preliminary data on changes in left ventricular mass, aortic pulse wave velocity, vascular access thromboses and health-related quality of life across study arms, which may be the secondary outcomes in the full-scale study. The data acquired in the pilot RCT will determine the feasibility and safety and inform the design of a full-scale trial, powered for hard outcomes, which may require 2000 participants.
Conservation biology for suites of species: Demographic modeling for Pacific island kingfishers
Kesler, D.C.; Haig, S.M.
2007-01-01
Conservation practitioners frequently extrapolate data from single-species investigations when managing critically endangered populations. However, few researchers initiate work with the intent of making findings useful to conservation efforts for other species. We presented and explored the concept of conducting conservation-oriented research for suites of geographically separated populations with similar natural histories, resource needs, and extinction threats. An example was provided in the form of an investigation into the population demography of endangered Micronesian kingfishers (Todiramphus cinnamominus). We provided the first demographic parameter estimates for any of the 12 endangered Pacific Todiramphus species, and used results to develop a population projection matrix model for management throughout the insular Pacific. Further, we used the model for elasticity and simulation analyses with demographic values that randomly varied across ranges that might characterize congener populations. Results from elasticity and simulation analyses indicated that changes in breeding adult survival exerted the greatest magnitude of influence on population dynamics. However, changes in nestling survival were more consistently correlated with population dynamics as demographic rates were randomly altered. We concluded that conservation practitioners working with endangered Pacific kingfishers should primarily focus efforts on factors affecting nestling and breeder survival, and secondarily address fledgling juveniles and helpers. Further, we described how the generalized base model might be changed to focus on individual populations and discussed the potential application of multi-species models to other conservation situations. ?? 2007 Elsevier Ltd. All rights reserved.
Ant-inspired density estimation via random walks.
Musco, Cameron; Su, Hsin-Hao; Lynch, Nancy A
2017-10-03
Many ant species use distributed population density estimation in applications ranging from quorum sensing, to task allocation, to appraisal of enemy colony strength. It has been shown that ants estimate local population density by tracking encounter rates: The higher the density, the more often the ants bump into each other. We study distributed density estimation from a theoretical perspective. We prove that a group of anonymous agents randomly walking on a grid are able to estimate their density within a small multiplicative error in few steps by measuring their rates of encounter with other agents. Despite dependencies inherent in the fact that nearby agents may collide repeatedly (and, worse, cannot recognize when this happens), our bound nearly matches what would be required to estimate density by independently sampling grid locations. From a biological perspective, our work helps shed light on how ants and other social insects can obtain relatively accurate density estimates via encounter rates. From a technical perspective, our analysis provides tools for understanding complex dependencies in the collision probabilities of multiple random walks. We bound the strength of these dependencies using local mixing properties of the underlying graph. Our results extend beyond the grid to more general graphs, and we discuss applications to size estimation for social networks, density estimation for robot swarms, and random walk-based sampling for sensor networks.
Lithium levels in tap water and psychotic experiences in a general population of adolescents.
Shimodera, Shinji; Koike, Shinsuke; Ando, Shuntaro; Yamasaki, Syudo; Fujito, Ryosuke; Endo, Kaori; Iijima, Yudai; Yamamoto, Yu; Morita, Masaya; Sawada, Ken; Ohara, Nobuki; Okazaki, Yuji; Nishida, Atsushi
2018-06-09
Recently, several epidemiologic studies have reported that lithium in drinking water may be associated with lower rates of suicide mortality, lower incidence of dementia, and lower levels of adolescents' depression and aggression at the population level. However, to our knowledge, no study has investigated lithium level in tap water in relation to psychotic experiences in a general population of adolescents. This is the first study to investigate this using a large dataset. Information on psychotic experiences, distress associated with these experiences, and depressive symptoms were collected in 24 public junior high schools in Kochi Prefecture in Japan. Samples were collected from sources that supplied drinking water to schools, and lithium levels were measured using atomic absorption spectrophotometry. The association of lithium levels with psychotic experiences, considering distress as a degree of severity, was examined using an ordinal logistic regression model with schools and depressive symptoms as random effects. In total, 3040 students responded to the self-reporting questionnaire (response rate: 91.8%). Lithium levels in tap water were inversely associated with psychotic experiences (p = 0.021). We concluded that lithium level in tap water was inversely associated with psychotic experiences among a general population of adolescents and may have a preventive effect for such experiences and distress. Copyright © 2018 Elsevier B.V. All rights reserved.
Evolutionary dynamics on any population structure
NASA Astrophysics Data System (ADS)
Allen, Benjamin; Lippner, Gabor; Chen, Yu-Ting; Fotouhi, Babak; Momeni, Naghmeh; Yau, Shing-Tung; Nowak, Martin A.
2017-03-01
Evolution occurs in populations of reproducing individuals. The structure of a population can affect which traits evolve. Understanding evolutionary game dynamics in structured populations remains difficult. Mathematical results are known for special structures in which all individuals have the same number of neighbours. The general case, in which the number of neighbours can vary, has remained open. For arbitrary selection intensity, the problem is in a computational complexity class that suggests there is no efficient algorithm. Whether a simple solution for weak selection exists has remained unanswered. Here we provide a solution for weak selection that applies to any graph or network. Our method relies on calculating the coalescence times of random walks. We evaluate large numbers of diverse population structures for their propensity to favour cooperation. We study how small changes in population structure—graph surgery—affect evolutionary outcomes. We find that cooperation flourishes most in societies that are based on strong pairwise ties.
Rossow, H; Ollgren, J; Hytonen, J; Rissanen, H; Huitu, O; Henttonen, H; Kuusi, M; Vapalahti, O
2015-08-20
We studied the incidence of reported tularaemia by year and region and the prevalence of antibodies against Francisella tularensis in the adult general population in Finland. Moreover, we assessed the correlation between vole population cycles and human tularaemia outbreaks. The seroprevalence study made use of serum samples from a nationwide population-based health survey (Health 2000). The samples of 1,045 randomly selected persons, representative for the Finnish population in each region, were screened with an enzyme-linked immunosorbent assay (ELISA) for the presence of IgG antibodies against F. tularensis, and positive results were further confirmed by immunoblotting. A serological response to F. tularensis was found in 2% (95% confidence interval: 1.1–3.5) of the population. Incidence and seroprevalence were highest in the same areas, and vole population peaks clearly preceded tularaemia outbreaks one year later.
Baltar, M.; Keeley, Jon E.; Schoenberg, F.P.
2013-01-01
The extent to which the apparent increase in wildfire incidence and burn area in California from 1990 to 2006 is affected by population and temperature increases is examined. Using generalized linear models with random effects, we focus on the estimated impacts of increases in mean daily temperatures and populations in different counties on wildfire in those counties, after essentially controlling for the overall differences between counties in their overall mean temperatures and populations. We find that temperature increase appears to have a significant positive impact on both total burn area and number of observed wildfires. Population growth appears to have a much less pronounced impact on total burn area than do annual temperature increases, and population growth appears to be negatively correlated with the total number of observed wildfires. These effects are especially pronounced in the winter season and in Southern California counties.
Obesity, Body Mass Index, and Homicide.
Omond, Kimberley J; Langlois, Neil E I; Byard, Roger W
2017-07-01
The body mass indexes (BMIs) of 100 randomly selected homicide cases from the files of Forensic Science SA were compared to the Australian and South Australian populations. There were 70 males and 30 females (M:F = 2.3:1; age range 18-84 years; mean 42.3 years). There was a substantially lower proportion of obese individuals in the homicide population compared to the general Australian and South Australian populations (19% [vs.] 27.9% and 30%, respectively). A second group of 144 randomly selected autopsy cases where the BMI was ≥40 kg/m 2 was analyzed. There were 77 males and 67 females (M:F = 1.2:1; age range 23-78 years; mean 46.7 years). The majority of deaths were natural (N = 108), with no homicides. A negative association between obesity and homicide has, therefore, been demonstrated. Reasons for the lower numbers of obese/morbidly obese individuals among homicide victims are unclear, but may include physical protection afforded by fat padding from sharp force injuries, and relative sociodemographic isolation. © 2016 American Academy of Forensic Sciences.
Mahesh, P A; Wong, Gary W K; Ogorodova, L; Potts, J; Leung, T F; Fedorova, O; Holla, Amrutha D; Fernandez-Rivas, M; Clare Mills, E N; Kummeling, I; Versteeg, S A; van Ree, R; Yazdanbakhsh, M; Burney, P
2016-07-01
Data are lacking regarding the prevalence of food sensitization and probable food allergy among general population in India. We report the prevalence of sensitization and probable food allergy to 24 common foods among adults from general population in Karnataka, South India. The study was conducted in two stages: a screening study and a case-control study. A total of 11 791 adults in age group 20-54 were randomly sampled from general population in South India and answered a screening questionnaire. A total of 588 subjects (236 cases and 352 controls) participated in the case-control study involving a detailed questionnaire and specific IgE estimation for 24 common foods. A high level of sensitization (26.5%) was observed for most of the foods in the general population, higher than that observed among adults in Europe, except for those foods that cross-react with birch pollen. Most of the sensitization was observed in subjects who had total IgE above the median IgE level. A high level of cross-reactivity was observed among different pollens and foods and among foods. The prevalence of probable food allergy (self-reports of adverse symptoms after the consumption of food and specific IgE to the same food) was 1.2%, which was mainly accounted for cow's milk (0.5%) and apple (0.5%). Very high levels of sensitization were observed for most foods, including those not commonly consumed in the general population. For the levels of sensitization, the prevalence of probable food allergy was low. This disassociation needs to be further explored in future studies. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
2013-01-01
Background 2,5-hexanedione (2,5-HD) is the main neurotoxic metabolite of methyl-n-butyl ketone (MBK) and n-hexane, and known to cause polyneuropathy. The aim of our study was to compare the urinary levels of 2,5-HD between cases with cryptogenic polyneuropathy and the general Swedish population, and to elucidate the role of certain external factors. Methods Morning urine samples were collected from 114 cases with cryptogenic polyneuropathy (77 men and 37 women) and 227 referents (110 men and 117 women) randomly selected from the population registry. None had any current occupational exposure to n-hexane or MBK. The urine samples were analysed by a gas chromatographic method based on acidic hydrolysis. Results Cases had statistically higher urinary levels of 2,5-HD (0.48 mg/L) than the general population (0.41 mg/L) and men higher excretion than women (0.48 mg/L and 0.38 mg/L, respectively). There was no difference in 2,5-HD levels between current smokers and non-smokers. Occupational exposure to xylene, alcohol consumption and ever exposed to general anaesthesia were associated with lower excretion in men while for occupational exposure to nitrous oxide in women higher excretion was seen. Higher excretion of 2,5 HD was inversely related to increasing age. Conclusions Significantly higher levels of urinary 2,5-HD were seen in men and cryptogenic polyneuropathy cases seemingly unexposed to n-hexane. Hypothetically, this might be due to either differences in metabolic patterns or some concealed exposure. The difference in means between cases and the general population is small and can therefore not allow any firm conclusions of the causality, however. PMID:23898939
Urolithiasis risk: a comparison between healthcare providers and the general population.
Chen, Ming-Hung; Weng, Shih-Feng; Hsu, Chien-Chin; Lin, Hung-Jung; Su, Shih-Bin; Wang, Jhi-Joung; Guo, How-Ran; Huang, Chien-Cheng
2016-07-18
Healthcare providers have many health-related risk factors that might contribute to urolithiasis: a heavy workload, a stressful workplace, and an unhealthy quality of life. However, the urolithiasis risk in healthcare providers is not clear. Using Taiwan's National Health Insurance Research Database, we identified 50,226 physicians, 20,677 pharmacists, 122,357 nurses, and 25,059 other healthcare providers as the study cohort and then randomly selected an identical number of patients who are not healthcare providers (general population) as the comparison cohort for this study. Conditional logistical regression analysis was used to compare the urolithiasis risk between healthcare providers and comparisons. Physician specialty subgroups were also analyzed. Physicians had a lower urolithiasis risk than did the general population (adjusted odds ratio [AOR]: 0.682; 95 % confidence interval [CI]: 0.634-0.732) and other healthcare providers (AOR: 0.661; 95 % CI 0.588-0.742) after adjusting for hypertension, diabetes, hyperlipidemia, coronary artery disease, and residence location. For pharmacists, nurses, and other healthcare providers, the urolithiasis risk was not significantly different than that for general population. Subgroup analysis showed that surgeons and family medicine physicians had a lower urolithiasis risk than did physician comparisons (AOR: 0.778; 95 % CI: 0.630-0.962 and AOR: 0.737; 95 % CI: 0.564-0.962, respectively). Although job stress and heavy workloads affect physicians' health, physicians had a lower urolithiasis risk than did the general population and other healthcare providers. This might be attributable to their greater medical knowledge and access to healthcare. Our findings provide useful information for public health policy makers about the disease risks of healthcare providers.
[Epidemiologic findings on the spontaneous long-term course of psychogenic disease over 10 years].
Franz, M; Schepank, H; Reister, G; Schellberg, D
1994-01-01
207 individuals were selected from a random sample of the adult urban population of Mannheim according to the criterion of medium psychogenic impairment (high-risk population) and investigated three times between 1979 and 1991 with regard to prevalence and severity of psychogenic disorders. In contrast to clinical investigations, the present data render statements on the spontaneous course of psychogenic disorders in the general population. The existing psychogenic impairment was determined by means of various operationalizations (symptomatology, ICD-diagnoses, severity of impairment). The available data indicate a high stability of psychogenic impairment in the spontaneous course. Group statistically the severity of impairment even increases in the long term course. However, different subtypes of course in the investigated high-risk population can be identified by a cluster analysis.
Geyer, Siegfried; Norozi, Kambiz; Buchhorn, Reiner; Wessel, Armin
2009-01-01
It was examined whether women and men (17-45 years) with operated congenital heart disease differ with respect to chances of employment. Patients were compared with the general population. Patients (n = 314) were classified by type of surgery (curative, reparative, palliative) as indicator of initial severity of disease. The second classification was performed according to a system proposed by the New York Heart Association in order to take reported impairments into account. Controls (n = 1165) consisted of a 10% random sample drawn from the German Socio-Economic Panel. Chances of full-time employment decreased as disease severity increased. Chances of part-time and minor employment were higher in patients than among controls. These general effects were because of male patients, while the employment patterns of women did not differ from the control group. Independent of patient status, women were more likely to have lower rates of full-time employment, and the rates of part-time and minor employment were higher. Long-term adaptation to impairments as a result of congenital heart disease differs between women and men with respect to employment status. While female patients do not differ from the general population, males may lower their engagement in paid work.
Introductory Statistics Students' Conceptual Understanding of Study Design and Conclusions
NASA Astrophysics Data System (ADS)
Fry, Elizabeth Brondos
Recommended learning goals for students in introductory statistics courses include the ability to recognize and explain the key role of randomness in designing studies and in drawing conclusions from those studies involving generalizations to a population or causal claims (GAISE College Report ASA Revision Committee, 2016). The purpose of this study was to explore introductory statistics students' understanding of the distinct roles that random sampling and random assignment play in study design and the conclusions that can be made from each. A study design unit lasting two and a half weeks was designed and implemented in four sections of an undergraduate introductory statistics course based on modeling and simulation. The research question that this study attempted to answer is: How does introductory statistics students' conceptual understanding of study design and conclusions (in particular, unbiased estimation and establishing causation) change after participating in a learning intervention designed to promote conceptual change in these areas? In order to answer this research question, a forced-choice assessment called the Inferences from Design Assessment (IDEA) was developed as a pretest and posttest, along with two open-ended assignments, a group quiz and a lab assignment. Quantitative analysis of IDEA results and qualitative analysis of the group quiz and lab assignment revealed that overall, students' mastery of study design concepts significantly increased after the unit, and the great majority of students successfully made the appropriate connections between random sampling and generalization, and between random assignment and causal claims. However, a small, but noticeable portion of students continued to demonstrate misunderstandings, such as confusion between random sampling and random assignment.
A general stochastic model for sporophytic self-incompatibility.
Billiard, Sylvain; Tran, Viet Chi
2012-01-01
Disentangling the processes leading populations to extinction is a major topic in ecology and conservation biology. The difficulty to find a mate in many species is one of these processes. Here, we investigate the impact of self-incompatibility in flowering plants, where several inter-compatible classes of individuals exist but individuals of the same class cannot mate. We model pollen limitation through different relationships between mate availability and fertilization success. After deriving a general stochastic model, we focus on the simple case of distylous plant species where only two classes of individuals exist. We first study the dynamics of such a species in a large population limit and then, we look for an approximation of the extinction probability in small populations. This leads us to consider inhomogeneous random walks on the positive quadrant. We compare the dynamics of distylous species to self-fertile species with and without inbreeding depression, to obtain the conditions under which self-incompatible species can be less sensitive to extinction while they can suffer more pollen limitation. © Springer-Verlag 2011
Johannessen, Håkon A; Tynes, Tore; Sterud, Tom
2013-06-01
To examine the impact of occupational role conflict and emotional demands on subsequent psychological distress. A randomly drawn cohort from the general Norwegian working-age population was followed up for 3 years (n = 12,550; response rate = 67%). Eligible respondents were in paid work during the reference week in 2006 and 2009 or temporarily absent from such work (n = 6,745; response rate = 68%). In the fully adjusted model, both high role conflict (odds ratios = 1.53; 95% CI = 1.15 to 2.03) and high emotional demands (odds ratios = 1.38; 95% CI = 1.13 to 1.69) were significant predictors of psychological distress. Additional significant predictors were low job control, bullying/harassment, and job insecurity (P < 0.05). Considering all of the evaluated work-related factors, role conflict and emotional demands contributed the most to the population risk of developing psychological distress.
Extinction in neutrally stable stochastic Lotka-Volterra models
NASA Astrophysics Data System (ADS)
Dobrinevski, Alexander; Frey, Erwin
2012-05-01
Populations of competing biological species exhibit a fascinating interplay between the nonlinear dynamics of evolutionary selection forces and random fluctuations arising from the stochastic nature of the interactions. The processes leading to extinction of species, whose understanding is a key component in the study of evolution and biodiversity, are influenced by both of these factors. Here, we investigate a class of stochastic population dynamics models based on generalized Lotka-Volterra systems. In the case of neutral stability of the underlying deterministic model, the impact of intrinsic noise on the survival of species is dramatic: It destroys coexistence of interacting species on a time scale proportional to the population size. We introduce a new method based on stochastic averaging which allows one to understand this extinction process quantitatively by reduction to a lower-dimensional effective dynamics. This is performed analytically for two highly symmetrical models and can be generalized numerically to more complex situations. The extinction probability distributions and other quantities of interest we obtain show excellent agreement with simulations.
Extinction in neutrally stable stochastic Lotka-Volterra models.
Dobrinevski, Alexander; Frey, Erwin
2012-05-01
Populations of competing biological species exhibit a fascinating interplay between the nonlinear dynamics of evolutionary selection forces and random fluctuations arising from the stochastic nature of the interactions. The processes leading to extinction of species, whose understanding is a key component in the study of evolution and biodiversity, are influenced by both of these factors. Here, we investigate a class of stochastic population dynamics models based on generalized Lotka-Volterra systems. In the case of neutral stability of the underlying deterministic model, the impact of intrinsic noise on the survival of species is dramatic: It destroys coexistence of interacting species on a time scale proportional to the population size. We introduce a new method based on stochastic averaging which allows one to understand this extinction process quantitatively by reduction to a lower-dimensional effective dynamics. This is performed analytically for two highly symmetrical models and can be generalized numerically to more complex situations. The extinction probability distributions and other quantities of interest we obtain show excellent agreement with simulations.
Morrison, Charles S.; Chen, Pai-Lien; Kwok, Cynthia; McCormack, Sheena; McGrath, Nuala; Watson-Jones, Deborah; Gottlieb, Sami L.
2018-01-01
Background Estimates of sexually transmitted infection (STI) prevalence are essential for efforts to prevent and control STIs. Few large STI prevalence studies exist, especially for low- and middle-income countries (LMICs). Our primary objective was to estimate the prevalence of chlamydia, gonorrhea, trichomoniasis, syphilis, herpes simplex virus type 2 (HSV-2), and bacterial vaginosis (BV) among women in sub-Saharan Africa by age, region, and population type. Methods and findings We analyzed individual-level data from 18 HIV prevention studies (cohort studies and randomized controlled trials; conducted during 1993–2011), representing >37,000 women, that tested participants for ≥1 selected STIs or BV at baseline. We used a 2-stage meta-analysis to combine data. After calculating the proportion of participants with each infection and standard error by study, we used a random-effects model to obtain a summary mean prevalence of each infection and 95% confidence interval (CI) across ages, regions, and population types. Despite substantial study heterogeneity for some STIs/populations, several patterns emerged. Across the three primary region/population groups (South Africa community-based, Southern/Eastern Africa community-based, and Eastern Africa higher-risk), prevalence was higher among 15–24-year-old than 25–49-year-old women for all STIs except HSV-2. In general, higher-risk populations had greater prevalence of gonorrhea and syphilis than clinic/community-based populations. For chlamydia, prevalence among 15–24-year-olds was 10.3% (95% CI: 7.4%, 14.1%; I2 = 75.7%) among women specifically recruited from higher-risk settings for HIV in Eastern Africa and was 15.1% (95% CI: 12.7%, 17.8%; I2 = 82.3%) in South African clinic/community-based populations. Among clinic/community-based populations, prevalence was generally greater in South Africa than in Southern/Eastern Africa for most STIs; for gonorrhea, prevalence among 15–24-year-olds was 4.6% (95% CI: 3.3%, 6.4%; I2 = 82.8%) in South Africa and was 1.7% (95% CI: 1.2%, 2.6%; I2 = 55.2%) in Southern/Eastern Africa. Across the three primary region/population groups, HSV-2 and BV prevalence was high among 25–49-year-olds (ranging from 70% to 83% and 33% to 44%, respectively). The main study limitation is that the data are not from random samples of the target populations. Conclusions Combining data from 18 HIV prevention studies, our findings highlight important features of STI/BV epidemiology among sub-Saharan African women. This methodology can be used where routine STI surveillance is limited and offers a new approach to obtaining critical information on STI and BV prevalence in LMICs. PMID:29485986
Kuo, Wan-Yin; Huang, Chien-Cheng; Weng, Shih-Feng; Lin, Hung-Jung; Su, Shih-Bin; Wang, Jhi-Joung; Guo, How-Ran; Hsu, Chien-Chin
2015-01-01
High stress levels and shift work probably trigger migraine in healthcare professionals (HCPs). However, the migraine risk differences between HCPs and the general population is unknown. This nationwide population-based cohort study used Taiwan's National Health Insurance Research Database. Physicians (50,226), nurses (122,357), and other HCPs (pharmacists, technicians, dietitians, rehabilitation therapists, social workers, etc.) (45,736) were enrolled for the study cohort, and randomly selected non-HCPs (218,319) were enrolled for the comparison cohort. Conditional logistical regression analysis was used to compare the migraine risks. Comparisons between HCPs and between physician specialties were also done. Physicians, nurses, and other HCPs had higher migraine risks than did the general population (adjusted odds ratio [AOR]: 1.672; 95 % confidence interval [CI]: 1.468-1.905, AOR: 1.621; 95 % CI: 1.532-1.714, and AOR: 1.254; 95 % CI: 1.124-1.399, respectively) after stroke, hypertension, epilepsy, anxiety, depression, and insomnia had been adjusted for. Nurses and physicians had higher migraine risks than did other HCPs (AOR: 1.303; 95 % CI: 1.206-1.408, and AOR: 1.193; 95 % CI: 1.069-1.332, respectively). Obstetricians and gynecologists had a lower migraine risk than did other physician specialists (AOR: 0.550; 95 % CI: 0.323-0.937). HCPs in Taiwan had a higher migraine risk than did the general population. Heavy workloads, emotional stress, and rotating night shift sleep disturbances appear to be the most important risk factors. These findings should provide an important reference for promoting occupational health in HCPs in Taiwan.
Calabrese, Sarah K; Underhill, Kristen; Earnshaw, Valerie A; Hansen, Nathan B; Kershaw, Trace S; Magnus, Manya; Krakower, Douglas S; Mayer, Kenneth H; Betancourt, Joseph R; Dovidio, John F
2016-07-01
Strategic framing of public messages about HIV pre-exposure prophylaxis (PrEP) may influence public support for policies and programs affecting access. This survey study examined how public attitudes toward PrEP differed based on the social group PrEP was described as benefiting ("beneficiary") and the moderating effect of prejudice. Members of the general public (n = 154) recruited online were randomly assigned to three beneficiary conditions: general population, gay men, or Black gay men. All participants received identical PrEP background information before completing measures of PrEP attitudes (specifying beneficiary), racism, and heterosexism. Despite anticipating greater PrEP adherence among gay men and Black gay men and perceiving PrEP as especially beneficial to the latter, participants expressed lower support for policies/programs making PrEP affordable for these groups vs. the general population. This disparity in support was stronger among participants reporting greater prejudice. Inclusive framing of PrEP in public discourse may prevent prejudice from undermining implementation efforts.
Calabrese, Sarah K.; Underhill, Kristen; Earnshaw, Valerie A.; Hansen, Nathan B.; Kershaw, Trace S.; Magnus, Manya; Krakower, Douglas S.; Mayer, Kenneth H.; Betancourt, Joseph R.; Dovidio, John F.
2016-01-01
Strategic framing of public messages about HIV pre-exposure prophylaxis (PrEP) may influence public support for policies and programs affecting access. This survey study examined how public attitudes toward PrEP differed based on the social group PrEP was described as benefiting (“beneficiary”) and the moderating effect of prejudice. Members of the general public (n = 154) recruited online were randomly assigned to three beneficiary conditions: general population, gay men, or Black gay men. All participants received identical PrEP background information before completing measures of PrEP attitudes (specifying beneficiary), racism, and heterosexism. Despite anticipating greater PrEP adherence among gay men and Black gay men and perceiving PrEP as especially beneficial to the latter, participants expressed lower support for policies/programs making PrEP affordable for these groups vs. the general population. This disparity in support was stronger among participants reporting greater prejudice. Inclusive framing of PrEP in public discourse may prevent prejudice from undermining implementation efforts. PMID:26891840
Premigration harm and depression: findings from the new immigrant survey, 2003.
Montgomery, Michelle A; Jackson, Charlotte T; Kelvin, Elizabeth A
2014-10-01
Studies examining refugees from conflict areas have found that persecution in the place of origin is a risk factor for depression. No studies have looked at this association between mental health and the experience of premigration harm due to race, gender or religion in the general population of United States immigrants. The New Immigrant Survey baseline questionnaire was administered to a random sample of adults receiving legal permanent residency in the U.S. in 2003 (n = 8,573), including refugees, asylees and other immigrants. In multivariate analysis controlling for visa type, premigration harm was a predictor of general depression of borderline statistical significance [odds ratio (OR), 1.33; 95 % CI 0.98-1.80, p = 0.068] and a significant predictor of major depression with dysphoria (OR, 2.24; 95 % CI 1.48-3.38, p = 0.0001). These findings suggest that premigration harm is a risk factor for depression in the general immigrant population and not just among refugees.
Dinnen, Stephanie; Simiola, Vanessa; Cook, Joan M
2015-01-01
Older adults represent the fastest growing segment of the US and industrialized populations. However, older adults have generally not been included in randomized clinical trials of psychotherapy for post-traumatic stress disorder (PTSD). This review examined reports of psychological treatment for trauma-related problems, primarily PTSD, in studies with samples of at least 50% adults aged 55 and older using standardized measures. A systematic review of the literature was conducted on psychotherapy for PTSD with older adults using PubMed, Medline, PsychInfo, CINAHL, PILOTS, and Google Scholar. A total of 42 studies were retrieved for full review; 22 were excluded because they did not provide at least one outcome measure or results were not reported by age in the case of mixed-age samples. Of the 20 studies that met review criteria, there were: 13 case studies or series, three uncontrolled pilot studies, two randomized clinical trials, one non-randomized concurrent control study and one post hoc effectiveness study. Significant methodological limitations in the current older adult PTSD treatment outcome literature were found reducing its internal validity and generalizability, including non-randomized research designs, lack of comparison conditions and small sample sizes. Select evidence-based interventions validated in younger and middle-aged populations appear acceptable and efficacious with older adults. There are few treatment studies on subsets of the older adult population including cultural and ethnic minorities, women, the oldest old (over 85), and those who are cognitively impaired. Implications for clinical practice and future research directions are discussed.
Time Evolving Fission Chain Theory and Fast Neutron and Gamma-Ray Counting Distributions
Kim, K. S.; Nakae, L. F.; Prasad, M. K.; ...
2015-11-01
Here, we solve a simple theoretical model of time evolving fission chains due to Feynman that generalizes and asymptotically approaches the point model theory. The point model theory has been used to analyze thermal neutron counting data. This extension of the theory underlies fast counting data for both neutrons and gamma rays from metal systems. Fast neutron and gamma-ray counting is now possible using liquid scintillator arrays with nanosecond time resolution. For individual fission chains, the differential equations describing three correlated probability distributions are solved: the time-dependent internal neutron population, accumulation of fissions in time, and accumulation of leaked neutronsmore » in time. Explicit analytic formulas are given for correlated moments of the time evolving chain populations. The equations for random time gate fast neutron and gamma-ray counting distributions, due to randomly initiated chains, are presented. Correlated moment equations are given for both random time gate and triggered time gate counting. There are explicit formulas for all correlated moments are given up to triple order, for all combinations of correlated fast neutrons and gamma rays. The nonlinear differential equations for probabilities for time dependent fission chain populations have a remarkably simple Monte Carlo realization. A Monte Carlo code was developed for this theory and is shown to statistically realize the solutions to the fission chain theory probability distributions. Combined with random initiation of chains and detection of external quanta, the Monte Carlo code generates time tagged data for neutron and gamma-ray counting and from these data the counting distributions.« less
Nichols, Thom R
The purpose of this study was to assess the Mental Health Component of health-related quality of life (HRQOL) in community-dwelling persons with ostomies residing in the United States. Cross-sectional descriptive study. Two thousand three hundred twenty-nine participants completed the survey for a response rate of 14.9% and a margin of error of 2.03%. Study respondents were geographically distributed throughout the United States, representing all 50 states. Fifty-three percent of study respondents were male. Respondents had a median age of 65 years. Forty percent have colostomies, 44% are living with ileostomies, and 13% have urostomies. The remaining 3% are living with multiple stomas or they indicated that they were uncertain as to the type of stoma. The SF36v2 was used to assess HRQOL. This instrument was selected because it has the ability to measure HRQOL in a target population and it allows comparison with the general population. Potential participants were randomly selected from an electronic database of 15,591 persons with ostomies. They were contacted by e-mails and provided with an electronic nontransferable link to the survey. This is a secondary analysis of findings from the Mental Component Summary (MCS) of the SF36v2. Persons who have undergone ostomy surgery did not score as well as the general population when components of the MCS were compared. While overall differences were identified, they differed based on age and cumulative MCS score levels. Analysis of individuals found to have significant impairment in MCS scores (cumulative soccer <40) tended to report less negative response than persons with comparable scores in the general population. Analysis also revealed that respondents aged 55 years or older had mental component domain scores that remained with the normal range of the general population. In contrast, participants who were younger than 55 years had lower scores that the general population. The overall MCS score of community-dwelling persons living with ostomies as lower than scores generated from the general population. However, these findings varied based on age and cumulative MCS score.
Colonoscopy screening for colorectal cancer: the outcomes of two recruitment methods.
Corbett, Mike; Chambers, Sharon L; Shadbolt, Bruce; Hillman, Lybus C; Taupin, Doug
2004-10-18
To determine the response to colorectal cancer (CRC) screening by colonoscopy, through direct invitation or through invitation by general practitioners. Two-way comparison of randomised population sampling versus cluster sampling of a representative general practice population in the Australian Capital Territory, May 2002 to January 2004. Invitation to screen, assessment for eligibility, interview, and colonoscopy. 881 subjects aged 55-74 years were invited to screen: 520 from the electoral roll (ER) sample and 361 from the general practice (GP) cluster sample. Response rate, participation rate, and rate of adenomatous polyps in the screened group. Participation was similar in the ER arm (35.1%; 95% CI, 30.2%-40.3%) and the GP arm (40.1%; 95% CI, 29.2%-51.0%) after correcting for ineligibility, which was higher in the ER arm. Superior eligibility in the GP arm was offset by the labour of manual record review. Response rates after two invitations were similar for the two groups (ER arm: 78.8%; 95% CI, 75.1%-82.1%; GP arm: 81.7%; 95% CI, 73.8%-89.6%). Overall, 53.4% ineligibility arose from having a colonoscopy in the past 10 years (ER arm, 98/178; GP arm, 42/84). Of 231 colonoscopies performed, 229 were complete, with 32% of subjects screened having adenomatous polyps. Colonoscopy-based CRC screening yields similar response and participation rates with either random population sampling or general practice cluster sampling, with population sampling through the electoral roll providing greater ease of recruitment.
A random spatial sampling method in a rural developing nation
Michelle C. Kondo; Kent D.W. Bream; Frances K. Barg; Charles C. Branas
2014-01-01
Nonrandom sampling of populations in developing nations has limitations and can inaccurately estimate health phenomena, especially among hard-to-reach populations such as rural residents. However, random sampling of rural populations in developing nations can be challenged by incomplete enumeration of the base population. We describe a stratified random sampling method...
Gerstner, Wulfram
2017-01-01
Neural population equations such as neural mass or field models are widely used to study brain activity on a large scale. However, the relation of these models to the properties of single neurons is unclear. Here we derive an equation for several interacting populations at the mesoscopic scale starting from a microscopic model of randomly connected generalized integrate-and-fire neuron models. Each population consists of 50–2000 neurons of the same type but different populations account for different neuron types. The stochastic population equations that we find reveal how spike-history effects in single-neuron dynamics such as refractoriness and adaptation interact with finite-size fluctuations on the population level. Efficient integration of the stochastic mesoscopic equations reproduces the statistical behavior of the population activities obtained from microscopic simulations of a full spiking neural network model. The theory describes nonlinear emergent dynamics such as finite-size-induced stochastic transitions in multistable networks and synchronization in balanced networks of excitatory and inhibitory neurons. The mesoscopic equations are employed to rapidly integrate a model of a cortical microcircuit consisting of eight neuron types, which allows us to predict spontaneous population activities as well as evoked responses to thalamic input. Our theory establishes a general framework for modeling finite-size neural population dynamics based on single cell and synapse parameters and offers an efficient approach to analyzing cortical circuits and computations. PMID:28422957
Schneider, Kristin L.; Pagoto, Sherry L.; Handschin, Barbara; Panza, Emily; Bakke, Susan; Liu, Qin; Blendea, Mihaela; Ockene, Ira S.; Ma, Yunsheng
2011-01-01
Background The comorbidity of type 2 diabetes mellitus (T2DM) and depression is associated with poor glycemic control. Exercise has been shown to improve mood and glycemic control, but individuals with comorbid T2DM and depression are disproportionately sedentary compared to the general population and report more difficulty with exercise. Behavioral activation, an evidence-based depression psychotherapy, was designed to help people with depression make gradual behavior changes, and may be helpful to build exercise adherence in sedentary populations. This pilot randomized clinical trial will test the feasibility of a group exercise program enhanced with behavioral activation strategies among women with comorbid T2DM and depression. Methods/Design Sedentary women with inadequately controlled T2DM and depression (N=60) will be randomly assigned to one of two conditions: exercise or usual care. Participants randomized to the exercise condition will attend 38 behavioral activation-enhanced group exercise classes over 24 weeks in addition to usual care. Participants randomized to the usual care condition will receive depression treatment referrals and print information on diabetes management via diet and physical activity. Assessments will occur at baseline and 3-, 6-, and 9-months following randomization. The goals of this pilot study are to demonstrate feasibility and intervention acceptability, estimate the resources and costs required to deliver the intervention and to estimate the standard deviation of continuous outcomes (e.g., depressive symptoms and glycosylated hemoglobin) in preparation for a fully-powered randomized clinical trial. Discussion A novel intervention that combines exercise and behavioral activation strategies could potentially improve glycemic control and mood in women with comorbid type 2 diabetes and depression. Trial registration NCT01024790 PMID:21765864
Yang, J; Cai, D; Wang, F; He, D; Ma, L; Jin, Y; Que, K
2016-12-01
This study investigated the prevalence, risk factors and association of occlusive wear with non-carious cervical lesions (NCCLs) in the general Chinese population. A total of 1320 subjects were recruited, and multistage and random sampling methods of survey spots were performed. All age groups comprised similar numbers of participants and equal numbers of males and females. Each subject completed a structured interview, and all teeth of each subject were examined by a practitioner to determine NCCLs and occlusive wear. Binary logistic regression was conducted by analysing the association of risk factors with the occurrence of NCCLs. Bivariate correlation analysis was performed by determining the association of NCCLs dimension or depth with the range of occlusive wear facets. Clinical assessment showed that the overall prevalence of subjects diagnosed with NCCLs was 63%. The proportion of subjects or teeth with NCCLs significantly increased with age. Pre-molars were the most commonly affected teeth. Single variables and interactive effects of variables associated with the occurrence of NCCLs include the following: age group, intensity of toothbrushing, frequency of fresh fruit consumption and interactive effect between intensity of toothbrushing and frequency of fresh fruit consumption. A weak positive correlation of the grading index was found between NCCLs dimension, size or depth and range of occlusive wear facets. This study reported the higher prevalence of NCCLs in the general Chinese population. Implementation of a combined strategy to reduce risk factors of NCCLs could be more effective than individual techniques; meanwhile, the occurrence of NCCL could be related to the wear degree of occlusive defects in the population studied. © 2016 John Wiley & Sons Ltd.
Clark, Christopher E; Taylor, Rod S; Shore, Angela C; Campbell, John L
2016-11-01
Various prevalence figures have been reported for inter-arm differences in blood pressure (IAD); variation may be explained by differing population vascular risk and by measurement method. To review the literature to derive robust estimates of IAD prevalence relevant to community populations. Systematic review and meta-analysis. MEDLINE, Embase, and CINAHL were searched for cross-sectional studies likely to represent general or primary care populations, reporting prevalence of IAD and employing a simultaneous method of measurement. Using study-level data, pooled estimates of mean prevalence of systolic IADs were calculated and compared using a random effects model. Eighty IAD studies were identified. Sixteen met inclusion criteria: pooled estimates of prevalence for systolic IAD ≥10 mmHg were 11.2% (95% confidence interval [CI] = 9.1 to 13.6) in hypertension, 7.4% (95% CI = 5.8 to 9.2) in diabetes, and 3.6% (95% CI = 2.3 to 5.0) for a general adult population (P<0.001 for subgroup differences). Differences persisted for higher cut-off values. Prevalences were lower for East Asian than for Western populations and were overestimated by sequential measurement where this could be compared with simultaneous measurement within studies (relative risk for IAD: 2.9 [95% CI = 2.1 to 4.1]). Studies with higher mean absolute systolic pressures had higher prevalences for a systolic IAD ≥10 mmHg (P = 0.04). Prevalences of IADs rise in relation to underlying cardiovascular comorbidities of the population studied, and are overestimated threefold when sequential measurement is used. Population-specific variation in prevalences of IAD should be taken into account in delivering clinical care and in planning future studies. © British Journal of General Practice 2016.
Food and fluid intake of the SENECA population residing in Romans, France.
Ferry, M; Hininger-Favier, I; Sidobre, B; Mathey, M F
2001-01-01
to provide information and data on food and fluid intake of free-living elderly aged of 81-86 years old residing in the south of France. using standardised methods data were collected from a random sample born between 1913 and 1918. The French study protocol again included data collection on dietary intake using a standardised modified dietary history consisting of a food frequency list and a 3-day estimated dietary record. Total dietary intake was generally low as compared to the recommended daily intake for elderly subjects. This descriptive part of the SENECA study gives the opportunity to have information on this growing segment of the population. These results should help to adapt the dietary guidelines for this category of the population.
Xu, Ziyan; Rüsch, Nicolas; Huang, Fangfang; Kösters, Markus
2017-09-01
Mental illness stigma is widely endorsed by the general public in China. Evidence-based anti-stigma interventions to reduce public stigma are needed. However, most studies on the efficacy of anti-stigma interventions took place in Western countries and existing Chinese studies were often not included in recent systematic reviews. This review evaluates the efficacy of anti-stigma interventions among the general population in Mainland China, Hong Kong, Taiwan and Macau. Eight databases in English and Chinese were searched for randomized and non-randomized controlled trials. Subgroup analyses compared interventions with and without consumer contact. Standardized mean differences were calculated from eligible studies where possible. We included 9 trials involving 2041 participants. Interventions yielded a small effect on stereotypes reduction and a similar effect on improving mental health literacy. No study assessed discrimination outcomes. Interventions with consumer contact were not superior to those without. There were insufficient data on medium and long term effects. Heterogeneity across studies was moderate. Quality of studies was modest. Further research using rigorous methods is required. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
Performance review using sequential sampling and a practice computer.
Difford, F
1988-06-01
The use of sequential sample analysis for repeated performance review is described with examples from several areas of practice. The value of a practice computer in providing a random sample from a complete population, evaluating the parameters of a sequential procedure, and producing a structured worksheet is discussed. It is suggested that sequential analysis has advantages over conventional sampling in the area of performance review in general practice.
Mahanta, Tulika G; Joshi, Rajnish; Mahanta, Bhupendra N; Xavier, Denis
2013-09-01
Risk factors for cardiovascular disease (CVD) are multifactorial. Previous research has reported a high prevalence of CVD risk factors in tea-garden workers. This study was conducted to assess prevalence and level of modifiable cardiovascular risk factors among tea-garden and general population in Dibrugarh, Assam. A community-based cross-sectional study using the World Health Organization's (WHO) Stepwise methodology was conducted in Dibrugarh District of Assam. A multistep random sampling was done to include adults aged 35 years and above, with an intended equal sampling from tea-garden and general population. INTERHEART modifiable non-laboratory based risk score was estimated. Salt consumption was estimated using questionnaire-based methods in both subgroups. A total of 2826 individuals participated in the study (1231 [43.6%] tea-garden workers; 1595 [56.4%] general population). Tobacco consumption was higher in tea-garden workers as compared with general population (85.2% vs. 41.7% (p < 0.0001). Mean daily per-capita salt consumption was also significantly higher among tea-garden workers (29.60 vs. 22.89 g, p = 0.0001). Overall prevalence of hypertension was similar (44.4% vs. 45.2%), but among those who had hypertension, prevalence of undiagnosed hypertension was higher in tea-garden workers (82.8% vs. 74.4%, p < 0.0001). Tea-garden workers had lower BMI, were more physically active, and had a lower prevalence of diabetes mellitus and metabolic syndrome. Their INTERHEART modifiable risk score was also lower (1.44 [2.5] vs. 1.79 [2.8], p = 0.001). High prevalence of modifiable risk factors like tobacco consumption, high salt intake and high prevalence of hypertension indicates the need for early implementation of preventive actions in this population. Copyright © 2013 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.
Hörnquist, Lina; Rickardsson, Jenny; Lannering, Birgitta; Gustafsson, Göran; Boman, Krister K
2015-05-01
Survivors of pediatric CNS tumors are at risk for persistent tumor/treatment-related morbidity, physical disability and social consequences that may alter self-perception, vital for self-identity, mental health and quality of survival. We studied the long-term impact of childhood CNS tumors and their treatment on the self-perception of adult survivors and compared outcomes with those of the general population. The cohort included 697 Swedish survivors diagnosed with a primary CNS tumor during 1982-2001. Comparison data were randomly collected from a stratified general population sample. Survivors and general population individuals were compared as regards self-perception in 5 domains: body image, sports/physical activities, peers, work, and family, and with a global self-esteem index. Within the survivor group, determinants of impact on self-perception were identified. The final analyzed sample included 528 survivors, 75.8% of the entire national cohort. The control sample consisted of 995, 41% of 2500 addressed. Survivors had significantly poorer self-perception outcomes in domains of peers, work, body image, and sports/physical activities, and in the global self-perception measure, compared with those of the general population (all P < .001). Within the survivor group, female gender and persistent visible physical sequelae predicted poorer outcomes in several of the studied domains. Tumor type and a history of cranial radiation therapy were associated with outcomes. An altered self-perception is a potential late effect in adult survivors of pediatric CNS tumors. Self-perception and self-esteem are significant elements of identity, mental health and quality of survival. Therefore, care and psychosocial follow-up of survivors should include measures for identifying disturbances and for assessing the need for psychosocial intervention. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Szolnoki, Attila; Perc, Matjaž
2016-12-05
Global, population-wide oscillations in models of cyclic dominance may result in the collapse of biodiversity due to the accidental extinction of one species in the loop. Previous research has shown that such oscillations can emerge if the interaction network has small-world properties, and more generally, because of long-range interactions among individuals or because of mobility. But although these features are all common in nature, global oscillations are rarely observed in actual biological systems. This begets the question what is the missing ingredient that would prevent local oscillations to synchronize across the population to form global oscillations. Here we show that, although heterogeneous species-specific invasion rates fail to have a noticeable impact on species coexistence, randomness in site-specific invasion rates successfully hinders the emergence of global oscillations and thus preserves biodiversity. Our model takes into account that the environment is often not uniform but rather spatially heterogeneous, which may influence the success of microscopic dynamics locally. This prevents the synchronization of locally emerging oscillations, and ultimately results in a phenomenon where one type of randomness is used to mitigate the adverse effects of other types of randomness in the system.
NASA Astrophysics Data System (ADS)
Szolnoki, Attila; Perc, Matjaž
2016-12-01
Global, population-wide oscillations in models of cyclic dominance may result in the collapse of biodiversity due to the accidental extinction of one species in the loop. Previous research has shown that such oscillations can emerge if the interaction network has small-world properties, and more generally, because of long-range interactions among individuals or because of mobility. But although these features are all common in nature, global oscillations are rarely observed in actual biological systems. This begets the question what is the missing ingredient that would prevent local oscillations to synchronize across the population to form global oscillations. Here we show that, although heterogeneous species-specific invasion rates fail to have a noticeable impact on species coexistence, randomness in site-specific invasion rates successfully hinders the emergence of global oscillations and thus preserves biodiversity. Our model takes into account that the environment is often not uniform but rather spatially heterogeneous, which may influence the success of microscopic dynamics locally. This prevents the synchronization of locally emerging oscillations, and ultimately results in a phenomenon where one type of randomness is used to mitigate the adverse effects of other types of randomness in the system.
Safety of Tamsulosin: A Systematic Review of Randomized Trials with a Focus on Women and Children.
Kaplan, Steven A; Chughtai, Bilal I
2018-05-08
Although tamsulosin is indicated for the treatment of the signs and symptoms of benign prostatic hyperplasia (BPH), it has also been assessed in clinical studies for other conditions/symptoms and in other populations such as women and children. In this systematic review of randomized studies, the overall safety of tamsulosin was assessed, focusing on these understudied populations. Literature searches were conducted using Embase, Medline, and PubMed (inception-December 2015). A study was included if patients were randomized to receive treatment with any dose of tamsulosin capsules, tablets, or an oral controlled absorption system and numerical safety results were reported. Overall, 160 articles involving 46,072 participants met the inclusion criteria. Of these, four studies included women only and three included children. The mean [standard deviation (SD)] age ranged from 7.3 (4.2) to 76.8 (7.1) years. The studies (n; %) evaluated healthy subjects (18; 11%) or patients with lower urinary tract symptoms/BPH (90; 56%), ureteral stones/renal colic (42; 26%), prostatitis (4; 3%), or other conditions (6; 4%). Patients discontinued tamsulosin primarily because of adverse events (AEs) or insufficient response. AEs in women and children were abdominal pain, asthenia, constipation, dizziness, dry mouth, drowsiness, dyspepsia, headache, incontinence, nasal congestion, nausea, orthostatic hypotension, and somnolence. Due to heterogeneity across studies, statistical analysis could not be conducted. No unexpected AEs were observed in an all-comers population treated with tamsulosin for various conditions/symptoms. The overall safety profile in women and children seemed to be generally consistent with the profile in men, the indicated population.
Baumann, Lukas; Cina, Manuel; Egli-Gany, Dianne; Goutaki, Myrofora; Halbeisen, Florian S; Lohrer, Gian-Reto; Ali, Hammad; Scott, Pippa; Low, Nicola
2018-06-01
Mycoplasma genitalium is a common cause of non-gonococcal non-chlamydial urethritis and cervicitis. Testing of asymptomatic populations has been proposed, but prevalence in asymptomatic populations is not well established. We aimed to estimate the prevalence of M. genitalium in the general population, pregnant women, men who have sex with men (MSM), commercial sex workers (CSWs) and clinic-based samples, METHODS: We searched Embase, Medline, IndMED, African Index Medicus and LILACS from 1 January 1991 to 12 July 2016 without language restrictions. We included studies with 500 participants or more. Two reviewers independently screened and selected studies and extracted data. We examined forest plots and conducted random-effects meta-analysis to estimate prevalence, if appropriate. Between-study heterogeneity was examined using the I 2 statistic and meta-regression. Of 3316 screened records, 63 were included. In randomly selected samples from the general population, the summary prevalence was 1.3% (95% CI 1.0% to 1.8%, I 2 41.5%, three studies, 9091 people) in countries with higher levels of development and 3.9% (95% CI 2.2 to 6.7, I 2 89.2%, three studies, 3809 people) in countries with lower levels. Prevalence was similar in women and men (P=0.47). In clinic based samples, prevalence estimates were higher, except in asymptomatic patients (0.8%, 95% CI 0.4 to 1.4, I 2 0.0%, three studies, 2889 people). Summary prevalence estimates were, in the following groups: pregnant women 0.9% (95% CI 0.6% to 1.4%, I 2 0%, four studies, 3472 people), MSM in the community 3.2% (95% CI 2.1 to 5.1, I 2 78.3%, five studies, 3012 people) and female CSWs in the community 15.9% (95% CI 13.5 to 18.9, I 2 79.9%, four studies, 4006 people). This systematic review can inform testing guidelines for M. genitalium . The low estimated prevalence of M. genitalium in the general population, pregnant women and asymptomatic attenders at clinics does not support expansion of testing to these groups. PROSPERO: CRD42015020420. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Bertolini, F; Galimberti, G; Schiavo, G; Mastrangelo, S; Di Gerlando, R; Strillacci, M G; Bagnato, A; Portolano, B; Fontanesi, L
2018-01-01
Commercial single nucleotide polymorphism (SNP) arrays have been recently developed for several species and can be used to identify informative markers to differentiate breeds or populations for several downstream applications. To identify the most discriminating genetic markers among thousands of genotyped SNPs, a few statistical approaches have been proposed. In this work, we compared several methods of SNPs preselection (Delta, F st and principal component analyses (PCA)) in addition to Random Forest classifications to analyse SNP data from six dairy cattle breeds, including cosmopolitan (Holstein, Brown and Simmental) and autochthonous Italian breeds raised in two different regions and subjected to limited or no breeding programmes (Cinisara, Modicana, raised only in Sicily and Reggiana, raised only in Emilia Romagna). From these classifications, two panels of 96 and 48 SNPs that contain the most discriminant SNPs were created for each preselection method. These panels were evaluated in terms of the ability to discriminate as a whole and breed-by-breed, as well as linkage disequilibrium within each panel. The obtained results showed that for the 48-SNP panel, the error rate increased mainly for autochthonous breeds, probably as a consequence of their admixed origin lower selection pressure and by ascertaining bias in the construction of the SNP chip. The 96-SNP panels were generally more able to discriminate all breeds. The panel derived by PCA-chrom (obtained by a preselection chromosome by chromosome) could identify informative SNPs that were particularly useful for the assignment of minor breeds that reached the lowest value of Out Of Bag error even in the Cinisara, whose value was quite high in all other panels. Moreover, this panel contained also the lowest number of SNPs in linkage disequilibrium. Several selected SNPs are located nearby genes affecting breed-specific phenotypic traits (coat colour and stature) or associated with production traits. In general, our results demonstrated the usefulness of Random Forest in combination to other reduction techniques to identify population informative SNPs.
Grande, R B; Aaseth, K; Lundqvist, C; Russell, M B
2009-11-01
The aim of the present study was to investigate the prevalence of new daily persistent headache (NDPH) in the general population, and compare the clinical characteristics of NDPH and chronic tension-type headache (CTTH). This is a population-based cross-sectional study. A random sample of 30 000 persons aged 30-44 years was drawn from the population of Akershus County, Norway. A postal questionnaire was screened for chronic headache. Those (n = 633) with self-reported chronic headache within the last month and/or year were invited to an interview and examination by a neurological resident. A follow-up interview was conducted after 1.5-3 years. The headaches were diagnosed according to the International Classification of Headache Disorders, 2nd edn and relevant revisions. The response rate of the questionnaire was 71% and the participation rate of the interview was 74%. Four persons, three men and one woman, had NDPH. The overall 1-year prevalence of NDPH was 0.03%. The clinical characteristics of NDPH and CTTH were similar, except for the sudden onset in DPH.Three of the four persons with NDPH had medication overuse. Follow-up disclosed that the symptomatology of NDPH is not unchangeable, since two persons had improvement of their NDPH. NDPH is rare and occurs in one of 3500 persons from the general population of 30-44-year-olds. It is often associated with medication overuse.
The treatment of medial tibial stress syndrome in athletes; a randomized clinical trial
2012-01-01
Background The only three randomized trials on the treatment of MTSS were all performed in military populations. The treatment options investigated in this study were not previously examined in athletes. This study investigated if functional outcome of three common treatment options for medial tibial stress syndrome (MTSS) in athletes in a non-military setting was the same. Methods The study design was randomized and multi-centered. Physical therapists and sports physicians referred athletes with MTSS to the hospital for inclusion. 81 athletes were assessed for eligibility of which 74 athletes were included and randomized to three treatment groups. Group one performed a graded running program, group two performed a graded running program with additional stretching and strengthening exercises for the calves, while group three performed a graded running program with an additional sports compression stocking. The primary outcome measure was: time to complete a running program (able to run 18 minutes with high intensity) and secondary outcome was: general satisfaction with treatment. Results 74 Athletes were randomized and included of which 14 did not complete the study due a lack of progress (18.9%). The data was analyzed on an intention-to-treat basis. Time to complete a running program and general satisfaction with the treatment were not significantly different between the three treatment groups. Conclusion This was the first randomized trial on the treatment of MTSS in athletes in a non-military setting. No differences were found between the groups for the time to complete a running program. Trial registration CCMO; NL23471.098.08 PMID:22464032
Differences between blood donors and a population sample: implications for case-control studies.
Golding, Jean; Northstone, Kate; Miller, Laura L; Davey Smith, George; Pembrey, Marcus
2013-08-01
Selecting appropriate controls for studies of genetic variation in case series is important. The two major candidates involve the use of blood donors or a random sample of the population. We compare and contrast the two different populations of controls for studies of genetic variation using data from parents enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). In addition we compute different biases using a series of hypothetical assumptions. The study subjects who had been blood donors differed markedly from the general population in social, health-related, anthropometric, and personality-related variables. Using theoretical examples, we show that blood donors are a poor control group for non-genetic studies of diseases related to environmentally, behaviourally, or socially patterned exposures. However, we show that if blood donors are used as controls in genetic studies, these factors are unlikely to make a major difference in detecting true associations with relatively rare disorders (cumulative incidence through life of <10%). Nevertheless, for more common disorders, the reduction in accuracy resulting from the inclusion in any control population of individuals who have or will develop the disease in question can create a greater bias than can socially patterned factors. Information about the medical history of a control and the parents of the control (as a proxy for whether the control will develop the disease) is more important with regard to the choice of controls than whether the controls are a random population sample or blood donors.
Reconstruction of Sensory Stimuli Encoded with Integrate-and-Fire Neurons with Random Thresholds
Lazar, Aurel A.; Pnevmatikakis, Eftychios A.
2013-01-01
We present a general approach to the reconstruction of sensory stimuli encoded with leaky integrate-and-fire neurons with random thresholds. The stimuli are modeled as elements of a Reproducing Kernel Hilbert Space. The reconstruction is based on finding a stimulus that minimizes a regularized quadratic optimality criterion. We discuss in detail the reconstruction of sensory stimuli modeled as absolutely continuous functions as well as stimuli with absolutely continuous first-order derivatives. Reconstruction results are presented for stimuli encoded with single as well as a population of neurons. Examples are given that demonstrate the performance of the reconstruction algorithms as a function of threshold variability. PMID:24077610
Applications of Geostatistics in Plant Nematology
Wallace, M. K.; Hawkins, D. M.
1994-01-01
The application of geostatistics to plant nematology was made by evaluating soil and nematode data acquired from 200 soil samples collected from the Ap horizon of a reed canary-grass field in northern Minnesota. Geostatistical concepts relevant to nematology include semi-variogram modelling, kriging, and change of support calculations. Soil and nematode data generally followed a spherical semi-variogram model, with little random variability associated with soil data and large inherent variability for nematode data. Block kriging of soil and nematode data provided useful contour maps of the data. Change of snpport calculations indicated that most of the random variation in nematode data was due to short-range spatial variability in the nematode population densities. PMID:19279938
Applications of geostatistics in plant nematology.
Wallace, M K; Hawkins, D M
1994-12-01
The application of geostatistics to plant nematology was made by evaluating soil and nematode data acquired from 200 soil samples collected from the A(p) horizon of a reed canary-grass field in northern Minnesota. Geostatistical concepts relevant to nematology include semi-variogram modelling, kriging, and change of support calculations. Soil and nematode data generally followed a spherical semi-variogram model, with little random variability associated with soil data and large inherent variability for nematode data. Block kriging of soil and nematode data provided useful contour maps of the data. Change of snpport calculations indicated that most of the random variation in nematode data was due to short-range spatial variability in the nematode population densities.
Hypnosis versus diazepam for embryo transfer: a randomized controlled study.
Catoire, Patrick; Delaunay, Laurent; Dannappel, Thomas; Baracchini, Dominique; Marcadet-Fredet, Sabine; Moreau, Olivier; Pacaud, Luc; Przyrowski, Daniel; Marret, Emmanuel
2013-04-01
Levitas et al. (2006) showed in a cohort study that hypnosis during embryo transfer (ET) increased pregnancy ratio by 76%. In order to evaluate hypnosis during ET in a general population, the authors performed a randomized prospective controlled study comparing diazepam (usual premedication) administered before ET plus muscle relaxation versus hypnosis plus placebo in 94 patients. Additionally, the authors studied anxiety pre and post ET. Anxiety scores were not different in the two groups before and after ET. No difference in pregnancy and birth ratio was found in the two groups. Hypnosis during ET is as effective as diazepam in terms of pregnancy ratio and anxiolytic effects, but with fewer side effects and should be routinely available.
Ant-inspired density estimation via random walks
Musco, Cameron; Su, Hsin-Hao
2017-01-01
Many ant species use distributed population density estimation in applications ranging from quorum sensing, to task allocation, to appraisal of enemy colony strength. It has been shown that ants estimate local population density by tracking encounter rates: The higher the density, the more often the ants bump into each other. We study distributed density estimation from a theoretical perspective. We prove that a group of anonymous agents randomly walking on a grid are able to estimate their density within a small multiplicative error in few steps by measuring their rates of encounter with other agents. Despite dependencies inherent in the fact that nearby agents may collide repeatedly (and, worse, cannot recognize when this happens), our bound nearly matches what would be required to estimate density by independently sampling grid locations. From a biological perspective, our work helps shed light on how ants and other social insects can obtain relatively accurate density estimates via encounter rates. From a technical perspective, our analysis provides tools for understanding complex dependencies in the collision probabilities of multiple random walks. We bound the strength of these dependencies using local mixing properties of the underlying graph. Our results extend beyond the grid to more general graphs, and we discuss applications to size estimation for social networks, density estimation for robot swarms, and random walk-based sampling for sensor networks. PMID:28928146
Gayoso-Diz, Pilar; Otero-Gonzalez, Alfonso; Rodriguez-Alvarez, María Xosé; Gude, Francisco; Cadarso-Suarez, Carmen; García, Fernando; De Francisco, Angel
2011-10-01
To describe the distribution of HOMA-IR levels in a general nondiabetic population and its relationships with metabolic and lifestyles characteristics. Cross-sectional study. Data from 2246 nondiabetic adults in a random Spanish population sample, stratified by age and gender, were analyzed. Assessments included a structured interview, physical examination, and blood sampling. Generalized additive models (GAMs) were used to assess the effect of lifestyle habits and clinical and demographic measurements on HOMA-IR. Multivariate GAMs and quantile regression analyses of HOMA-IR were carried out separately in men and women. This study shows refined estimations of HOMA-IR levels by age, body mass index, and waist circumference in men and women. HOMA-IR levels were higher in men (2.06) than women (1.95) (P=0.047). In women, but not men, HOMA-IR and age showed a significant nonlinear association (P=0.006), with increased levels above fifty years of age. We estimated HOMA-IR curves percentile in men and women. Age- and gender-adjusted HOMA-IR levels are reported in a representative Spanish adult non-diabetic population. There are gender-specific differences, with increased levels in women over fifty years of age that may be related with changes in body fat distribution after menopause. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
Stochastic Dynamics through Hierarchically Embedded Markov Chains
NASA Astrophysics Data System (ADS)
Vasconcelos, Vítor V.; Santos, Fernando P.; Santos, Francisco C.; Pacheco, Jorge M.
2017-02-01
Studying dynamical phenomena in finite populations often involves Markov processes of significant mathematical and/or computational complexity, which rapidly becomes prohibitive with increasing population size or an increasing number of individual configuration states. Here, we develop a framework that allows us to define a hierarchy of approximations to the stationary distribution of general systems that can be described as discrete Markov processes with time invariant transition probabilities and (possibly) a large number of states. This results in an efficient method for studying social and biological communities in the presence of stochastic effects—such as mutations in evolutionary dynamics and a random exploration of choices in social systems—including situations where the dynamics encompasses the existence of stable polymorphic configurations, thus overcoming the limitations of existing methods. The present formalism is shown to be general in scope, widely applicable, and of relevance to a variety of interdisciplinary problems.
A critical appraisal of lubiprostone in the treatment of chronic constipation in the elderly.
Gras-Miralles, Beatriz; Cremonini, Filippo
2013-01-01
Chronic constipation is a common disorder in the general population, with higher prevalence in the elderly, and is associated with worse quality of life and with greater health care utilization. Lubiprostone is an intestinal type-2 chloride channel activator that increases intestinal fluid secretion, small intestinal transit, and stool passage. Lubiprostone is currently approved by the US Food and Drug Administration for the treatment of chronic idiopathic constipation and of irritable bowel syndrome with predominant constipation. This review outlines current approaches and limitations in the treatment of chronic constipation in the elderly and discusses the results, limitations, and applicability of randomized, controlled trials of lubiprostone that have been conducted in the general and elderly population, with additional focus on the use of lubiprostone in constipation in Parkinson's disease and in opioid-induced constipation, two clinical entities that can be comorbid in elderly patients.
Stochastic Dynamics through Hierarchically Embedded Markov Chains.
Vasconcelos, Vítor V; Santos, Fernando P; Santos, Francisco C; Pacheco, Jorge M
2017-02-03
Studying dynamical phenomena in finite populations often involves Markov processes of significant mathematical and/or computational complexity, which rapidly becomes prohibitive with increasing population size or an increasing number of individual configuration states. Here, we develop a framework that allows us to define a hierarchy of approximations to the stationary distribution of general systems that can be described as discrete Markov processes with time invariant transition probabilities and (possibly) a large number of states. This results in an efficient method for studying social and biological communities in the presence of stochastic effects-such as mutations in evolutionary dynamics and a random exploration of choices in social systems-including situations where the dynamics encompasses the existence of stable polymorphic configurations, thus overcoming the limitations of existing methods. The present formalism is shown to be general in scope, widely applicable, and of relevance to a variety of interdisciplinary problems.
Social inheritance can explain the structure of animal social networks
Ilany, Amiyaal; Akçay, Erol
2016-01-01
The social network structure of animal populations has major implications for survival, reproductive success, sexual selection and pathogen transmission of individuals. But as of yet, no general theory of social network structure exists that can explain the diversity of social networks observed in nature, and serve as a null model for detecting species and population-specific factors. Here we propose a simple and generally applicable model of social network structure. We consider the emergence of network structure as a result of social inheritance, in which newborns are likely to bond with maternal contacts, and via forming bonds randomly. We compare model output with data from several species, showing that it can generate networks with properties such as those observed in real social systems. Our model demonstrates that important observed properties of social networks, including heritability of network position or assortative associations, can be understood as consequences of social inheritance. PMID:27352101
A critical appraisal of lubiprostone in the treatment of chronic constipation in the elderly
Gras-Miralles, Beatriz; Cremonini, Filippo
2013-01-01
Chronic constipation is a common disorder in the general population, with higher prevalence in the elderly, and is associated with worse quality of life and with greater health care utilization. Lubiprostone is an intestinal type-2 chloride channel activator that increases intestinal fluid secretion, small intestinal transit, and stool passage. Lubiprostone is currently approved by the US Food and Drug Administration for the treatment of chronic idiopathic constipation and of irritable bowel syndrome with predominant constipation. This review outlines current approaches and limitations in the treatment of chronic constipation in the elderly and discusses the results, limitations, and applicability of randomized, controlled trials of lubiprostone that have been conducted in the general and elderly population, with additional focus on the use of lubiprostone in constipation in Parkinson’s disease and in opioid-induced constipation, two clinical entities that can be comorbid in elderly patients. PMID:23439964
LaMarr, June; Levy, Rona L.; Pearson, Cynthia; Maresca, Teresa; Mohammed, Selina A.; Simoni, Jane M.; Evans-Campbell, Teresa; Fredriksen-Goldsen, Karen; Fryberg, Sheryl; Jobe, Jared B.
2012-01-01
American Indian and Alaska Native (AIAN) populations are disproportionately at risk for cardiovascular disease (CVD), diabetes, and obesity, compared with the general US population. This article describes the həli?dxw/Healthy Hearts Across Generations project, an AIAN-run, tribally based randomized controlled trial (January 2010–June 2012) designed to evaluate a culturally appropriate CVD risk prevention program for AI parents residing in the Pacific Northwest of the United States. At-risk AIAN adults (n = 135) were randomly assigned to either a CVD prevention intervention arm or a comparison arm focusing on increasing family cohesiveness, communication, and connectedness. Both year-long conditions included 1 month of motivational interviewing counseling followed by personal coach contacts and family life-skills classes. Blood chemistry, blood pressure, body mass index, food intake, and physical activity were measured at baseline and at 4- and 12-month follow-up times. PMID:22965622
Walters, Karina L; LaMarr, June; Levy, Rona L; Pearson, Cynthia; Maresca, Teresa; Mohammed, Selina A; Simoni, Jane M; Evans-Campbell, Teresa; Fredriksen-Goldsen, Karen; Fryberg, Sheryl; Jobe, Jared B
2012-08-01
American Indian and Alaska Native (AIAN) populations are disproportionately at risk for cardiovascular disease (CVD), diabetes, and obesity, compared with the general US population. This article describes the həli?dx(w)/Healthy Hearts Across Generations project, an AIAN-run, tribally based randomized controlled trial (January 2010-June 2012) designed to evaluate a culturally appropriate CVD risk prevention program for AI parents residing in the Pacific Northwest of the United States. At-risk AIAN adults (n = 135) were randomly assigned to either a CVD prevention intervention arm or a comparison arm focusing on increasing family cohesiveness, communication, and connectedness. Both year-long conditions included 1 month of motivational interviewing counseling followed by personal coach contacts and family life-skills classes. Blood chemistry, blood pressure, body mass index, food intake, and physical activity were measured at baseline and at 4- and 12-month follow-up times.
Oldenburg, Catherine E.; Perez-Brumer, Amaya G.; Reisner, Sari L.; Mattie, Jason; Bärnighausen, Till; Mayer, Kenneth H.; Mimiaga, Matthew J.
2014-01-01
Background Men who engage in transactional sex, the exchange of sex for money, goods, or other items of value, are thought to be at increased risk of HIV, but there have been no systematic attempts to characterize HIV burden in this population. We undertook a systematic review and meta-analysis to quantify the burden in this population compared with that of men in the general population to better inform future HIV prevention efforts. Methods We searched seven electronic databases, national surveillance reports, and conference abstracts for studies of men who engage in transactional sex published between 2004–2013. Random effects meta-analysis was used to determine pooled HIV prevalence and prevalence ratios (PR) for the difference in HIV prevalence among men who engage in transactional sex as compared to general population men. Findings Of 66 studies included representing 31,924 men who had engaged in transactional sex in 28 countries, pooled biological assay-confirmed HIV prevalence was 10.5% (95% CI = 9.4 to 11.5%). The highest pooled HIV prevalence was in Sub-Saharan Africa (31.5%, 95% CI = 21.6 to 41.5%), followed by Latin America (19.3%, 95% CI = 15.5 to 23.1%), North America (16.6%, 95% CI = 3.7 to 29.5%), and Europe (12.2%, 95% CI = 6.0 to 17.2%). Men who engaged in transactional sex had an elevated burden of HIV compared to the general male population (PR = 20.7, 95% CI = 16.8 to 25.5). Conclusions The global burden of HIV is disproportionately high among men who engage in transactional sex compared with the general male population. There is an urgent need to include this population in systematic surveillance as well as to scale-up access to quality HIV prevention programs. PMID:25068720
Kopjar, Nevenka; Kasuba, Vilena; Milić, Mirta; Rozgaj, Ruzica; Zeljezić, Davor; Gajski, Goran; Mladinić, Marin; Garaj-Vrhovac, Vera
2010-06-01
The cytokinesis-block micronucleus (CBMN) assay on peripheral blood lymphocytes is one of the most important methods employed in cytogenetic biomonitoring. For the purposes of biological dosimetry, it is important to know the spontaneous frequency of a biomarker and its normal values in general population. These values are used for population databases, which should be updated regularly. In this study, MN levels were investigated in cytokinesis-blocked lymphocytes of 200 healthy male and female blood donors selected at random from the general population of Croatia. The aim was to assess the variability and determine possible influences of external and/or internal factors on the background levels of MN and to establish the cut-off value for the CBMN assay. The background frequency of MN was (6.90+/-3.32) MN (median 7 MN) and the range was 0 to 18 MN per 1000 binuclear lymphocytes. The cut-off value, which corresponds to 95th percentile of the distribution of 200 individual values, was 12.5 MN. Spontaneous formation of MN was influenced by sex, age, and smoking. Women had higher MN levels than men. However, only age and smoking significantly increased the values of all parameters evaluated by the CBMN assay. Since the existing literature data on smoking-related formation of MN are contradictory, we will continue these investigations to resolve how the number of cigarettes smoked per day and the duration of smoking in years influence the results of the CBMN assay. Our results are consistent with the background MN frequencies reported by other cytogenetic laboratories worldwide. Normal and cut-off values estimated in this study will be used to update the current general population data and as reference for occupationally or accidental exposure.
Birth order and post-traumatic stress disorder.
Green, Ben; Griffiths, Emily C
2014-01-01
To compare the birth order of patients with post-traumatic stress disorder (PTSD) and adjustment disorder (AD) with population norms. 83 PTSD patients and 104 AD control patients from a psychiatric trauma clinic were diagnosed according to DCR-10 guidelines. A family history was taken as to number of siblings, and their birth order. We compared the distribution of birth order for each patient group against birth order distributions expected by chance for the same years of birth using UK population-level birth order from the Office for National Statistics. Psychiatric patients with PTSD were more likely to be from a large family, specifically to be the fifth child or later (OR 4.78, p < .001) and less likely to be the eldest child (OR .65, p < .001) than the general population in England and Wales. There were no differences for birth order between AD patients and the general population. People with PTSD are more likely to be the youngest children from large families than expected from a random sample of people born in the same years. This association with birth order was not found for another psychiatric diagnosis AD from the same clinic. We discuss possible psychosocial and biological causes, and implications for further research.
Potential impact of spatially targeted adult tuberculosis vaccine in Gujarat, India
Chatterjee, Susmita; Rao, Krishna D.; Dowdy, David W.
2016-01-01
Some of the most promising vaccines in the pipeline for tuberculosis (TB) target adolescents and adults. Unlike for childhood vaccines, high-coverage population-wide vaccination is significantly more challenging for adult vaccines. Here, we aimed to estimate the impact of vaccine delivery strategies that were targeted to high-incidence geographical ‘hotspots’ compared with randomly allocated vaccination. We developed a spatially explicit mathematical model of TB transmission that distinguished these hotspots from the general population. We evaluated the impact of targeted and untargeted vaccine delivery strategies in India—a country that bears more than 25% of global TB burden, and may be a potential early adopter of the vaccine. We collected TB notification data and conducted a demonstration study in the state of Gujarat to validate our estimates of heterogeneity in TB incidence. We then projected the impact of randomly vaccinating 8% of adults in a single mass campaign to a spatially targeted vaccination preferentially delivered to 80% of adults in the hotspots, with both strategies augmented by continuous adolescent vaccination. In consultation with vaccine developers, we considered a vaccine efficacy of 60%, and evaluated the population-level impact after 10 years of vaccination. Spatial heterogeneity in TB notification (per 100 000/year) was modest in Gujarat: 190 in the hotspots versus 125 in the remaining population. At this level of heterogeneity, the spatially targeted vaccination was projected to reduce TB incidence by 28% after 10 years, compared with a 24% reduction projected to achieve via untargeted vaccination—a 1.17-fold augmentation in the impact of vaccination by spatially targeting. The degree of the augmentation was robust to reasonable variation in natural history assumptions, but depended strongly on the extent of spatial heterogeneity and mixing between the hotspot and general population. Identifying high-incidence hotspots and quantifying spatial mixing patterns are critical to accurate estimation of the value of targeted intervention strategies. PMID:27009179
Improvement of Predictive Ability by Uniform Coverage of the Target Genetic Space
Bustos-Korts, Daniela; Malosetti, Marcos; Chapman, Scott; Biddulph, Ben; van Eeuwijk, Fred
2016-01-01
Genome-enabled prediction provides breeders with the means to increase the number of genotypes that can be evaluated for selection. One of the major challenges in genome-enabled prediction is how to construct a training set of genotypes from a calibration set that represents the target population of genotypes, where the calibration set is composed of a training and validation set. A random sampling protocol of genotypes from the calibration set will lead to low quality coverage of the total genetic space by the training set when the calibration set contains population structure. As a consequence, predictive ability will be affected negatively, because some parts of the genotypic diversity in the target population will be under-represented in the training set, whereas other parts will be over-represented. Therefore, we propose a training set construction method that uniformly samples the genetic space spanned by the target population of genotypes, thereby increasing predictive ability. To evaluate our method, we constructed training sets alongside with the identification of corresponding genomic prediction models for four genotype panels that differed in the amount of population structure they contained (maize Flint, maize Dent, wheat, and rice). Training sets were constructed using uniform sampling, stratified-uniform sampling, stratified sampling and random sampling. We compared these methods with a method that maximizes the generalized coefficient of determination (CD). Several training set sizes were considered. We investigated four genomic prediction models: multi-locus QTL models, GBLUP models, combinations of QTL and GBLUPs, and Reproducing Kernel Hilbert Space (RKHS) models. For the maize and wheat panels, construction of the training set under uniform sampling led to a larger predictive ability than under stratified and random sampling. The results of our methods were similar to those of the CD method. For the rice panel, all training set construction methods led to similar predictive ability, a reflection of the very strong population structure in this panel. PMID:27672112
2017-01-01
Depressive disorder is a common mental illness and remains a major cause of morbidity worldwide. The present study, a cross-sectional, nationwide, population-based survey assessed the prevalence of depression in the general population of Korea through a random sampling of the non-institutionalized population for the Korea National Health and Nutrition Examination Survey (KNHANES) VI. The Patient Health Questionnaire (PHQ)-9 was first introduced into the KNHANES to detect depression. The point prevalence of depression (PHQ score of 10 or higher) was 6.7% (95% confidence interval [CI], 5.7–7.6) in 4,949 subjects. Based on the analysis using the diagnostic algorithm of the PHQ-9, the prevalence of major depressive disorder was 2.7% (95% CI, 2.2–3.3). Multiple logistic regression analysis, after adjusting the sociodemographic variables, also showed that the factors associated with depression were perceived stress and health status. This study reported for the first time that the point prevalence of depression screened using the PHQ-9 in this nationwide survey of the Korean population was similar to that of the western countries. As the KNHANES to detect depression is conducted biennially, further studies on the accumulated data are expected in the future. PMID:28960042
Aagestad, Cecilie; Tyssen, Reidar; Sterud, Tom
2016-03-08
Doctor -certified sick leave is prevalent in the health and social sector. We examined whether the higher risk of doctor-certified sick leave in women in health and social occupations compared to women in other occupations was explained by particular work-related psychosocial and mechanical risk factors. A randomly drawn cohort aged 18-69 years from the general population in Norway was surveyed in 2009 (n = 12,255, response at baseline = 60.9 %), and was followed up in the national registry of social transfer payments in 2010. Eligible respondents were women registered with an active employee relationship for ≥100 actual working days in 2009 and 2010 (n = 3032). Using this sample, we compared health and social workers (n = 661) with the general working population (n = 2371). The outcome of interest was long-term sick leave (LTSL) ≥21 working days during 2010. Eight psychosocial and eight mechanical factors were evaluated. After adjusting for age, previous LTSL, education and working hours/week, women in health and social occupations had a higher risk for LTSL compared with women in the general working population (OR = 1.42, 95 % CI = 1.13-1.79; p = 0.003). After adjusting for psychosocial and mechanical factors, 70 % of the excess risk for LTSL was explained compared with the initial model. The main contributory factors to the increased risk were threats of violence and violence, emotional demands and awkward lifting. Psychosocial and mechanical factors explained much of the excess risk for LTSL in women in health and social occupations compared with working women in general. Psychosocial risk factors were the most important contributors.
Occurence of internet addiction in a general population sample: a latent class analysis.
Rumpf, Hans-Jürgen; Vermulst, Ad A; Bischof, Anja; Kastirke, Nadin; Gürtler, Diana; Bischof, Gallus; Meerkerk, Gert-Jan; John, Ulrich; Meyer, Christian
2014-01-01
Prevalence studies of Internet addiction in the general population are rare. In addition, a lack of approved criteria hampers estimation of its occurrence. This study conducted a latent class analysis (LCA) in a large general population sample to estimate prevalence. A telephone survey was conducted based on a random digit dialling procedure including landline telephone (n=14,022) and cell phone numbers (n=1,001) in participants aged 14-64. The Compulsive Internet Use Scale (CIUS) served as the basis for a LCA used to look for subgroups representing participants with Internet addiction or at-risk use. CIUS was given to participants reporting to use the Internet for private purposes at least 1 h on a typical weekday or at least 1 h on a day at the weekend (n=8,130). A 6-class model showed best model fit and included two groups likely to represent Internet addiction and at-risk Internet use. Both groups showed less social participation and the Internet addiction group less general trust in other people. Proportions of probable Internet addiction were 1.0% (CI 0.9-1.2) among the entire sample, 2.4% (CI 1.9-3.1) in the age group 14-24, and 4.0% (CI 2.7-5.7) in the age group 14-16. No difference in estimated proportions between males and females was found. Unemployment (OR 3.13; CI 1.74-5.65) and migration background (OR 3.04; CI 2.12-4.36) were related to Internet addiction. This LCA-based study differentiated groups likely to have Internet addiction and at-risk use in the general population and provides characteristics to further define this rather new disorder. © 2013 S. Karger AG, Basel.
How random is a random vector?
NASA Astrophysics Data System (ADS)
Eliazar, Iddo
2015-12-01
Over 80 years ago Samuel Wilks proposed that the "generalized variance" of a random vector is the determinant of its covariance matrix. To date, the notion and use of the generalized variance is confined only to very specific niches in statistics. In this paper we establish that the "Wilks standard deviation" -the square root of the generalized variance-is indeed the standard deviation of a random vector. We further establish that the "uncorrelation index" -a derivative of the Wilks standard deviation-is a measure of the overall correlation between the components of a random vector. Both the Wilks standard deviation and the uncorrelation index are, respectively, special cases of two general notions that we introduce: "randomness measures" and "independence indices" of random vectors. In turn, these general notions give rise to "randomness diagrams"-tangible planar visualizations that answer the question: How random is a random vector? The notion of "independence indices" yields a novel measure of correlation for Lévy laws. In general, the concepts and results presented in this paper are applicable to any field of science and engineering with random-vectors empirical data.
Serum iron level and kidney function: a Mendelian randomization study.
Del Greco M, Fabiola; Foco, Luisa; Pichler, Irene; Eller, Philipp; Eller, Kathrin; Benyamin, Beben; Whitfield, John B; Pramstaller, Peter P; Thompson, John R; Pattaro, Cristian; Minelli, Cosetta
2017-02-01
Iron depletion is a known consequence of chronic kidney disease (CKD), but there is contradicting epidemiological evidence on whether iron itself affects kidney function and whether its effect is protective or detrimental in the general population. While epidemiological studies tend to be affected by confounding and reverse causation, Mendelian randomization (MR) can provide unconfounded estimates of causal effects by using genes as instruments. We performed an MR study of the effect of serum iron levels on estimated glomerular filtration rate (eGFR), using genetic variants known to be associated with iron. MR estimates of the effect of iron on eGFR were derived based on the association of each variant with iron and eGFR from two large genome-wide meta-analyses on 48 978 and 74 354 individuals. We performed a similar MR analysis for ferritin, which measures iron stored in the body, using variants associated with ferritin. A combined MR estimate across all variants showed a 1.3% increase in eGFR per standard deviation increase in iron (95% confidence interval 0.4–2.1%; P = 0.004). The results for ferritin were consistent with those for iron. Secondary MR analyses of the effects of iron and ferritin on CKD did not show significant associations but had very low statistical power. Our study suggests a protective effect of iron on kidney function in the general population. Further research is required to confirm this causal association, investigate it in study populations at higher risk of CKD and explore its underlying mechanism of action.
Plotnikoff, Ronald C; Rhodes, Ryan E; Trinh, Linda
2009-11-01
The purpose of this study was to examine the Protection Motivation Theory (PMT) to predict physical activity (PA) behaviour in a large, population-based sample of adults. One thousand six hundred and two randomly selected individuals completed two telephone interviews over two consecutive six-month periods assessing PMT constructs. PMT explained 35 per cent and 20 per cent of the variance in intention and behaviour respectively. Coping cognitions as moderators of threat explained 1 per cent of the variance in intention and behaviour. Age and gender as moderators of threat did not provide additional variance in the models. We conclude that salient PMT predictors (e.g. self-efficacy) may guide the development of effective PA interventions in the general population.
The influence of neighborhood unemployment on mortality after stroke.
Unrath, Michael; Wellmann, Jürgen; Diederichs, Claudia; Binse, Lisa; Kalic, Marianne; Heuschmann, Peter Ulrich; Berger, Klaus
2014-07-01
Few studies have investigated the impact of neighborhood characteristics on mortality after stroke. Aim of our study was to analyze the influence of district unemployment as indicator of neighborhood socioeconomic status (SES-NH) on poststroke mortality, and to compare these results with the mortality in the underlying general population. Our analyses involve 2 prospective cohort studies from the city of Dortmund, Germany. In the Dortmund Stroke Register (DOST), consecutive stroke patients (N=1883) were recruited from acute care hospitals. In the Dortmund Health Study (DHS), a random general population sample was drawn (n=2291; response rate 66.9%). Vital status was ascertained in the city's registration office and information on district unemployment was obtained from the city's statistical office. We performed multilevel survival analyses to examine the association between district unemployment and mortality. The association between neighborhood unemployment and mortality was weak and not statistically significant in the stroke cohort. Only stroke patients exposed to the highest district unemployment (fourth quartile) had slightly higher mortality risks. In the general population sample, higher district unemployment was significantly associated with higher mortality following a social gradient. After adjustment for education, health-related behavior and morbidity was made the strength of this association decreased. The impact of SES-NH on mortality was different for stroke patients and the general population. Differences in the association between SES-NH and mortality may be partly explained by disease-related characteristics of the stroke cohort such as homogeneous lifestyles, similar morbidity profiles, medical factors, and old age. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.
The epidemiology of hepatitis C virus in Afghanistan: systematic review and meta-analysis.
Chemaitelly, Hiam; Mahmud, Sarwat; Rahmani, Ahmad Masoud; Abu-Raddad, Laith J
2015-11-01
To characterize hepatitis C virus (HCV) epidemiology and inform public health research, policy, and programming priorities in Afghanistan. Records of HCV incidence and prevalence were reviewed systematically and synthesized following PRISMA guidelines. Meta-analyses were implemented using a DerSimonian-Laird random effects model with inverse variance weighting to estimate HCV prevalence among various at risk populations. A risk of bias assessment was incorporated. The search identified one HCV incidence and 76 HCV prevalence measures. HCV incidence was only assessed among people who inject drugs (PWID), and was reported at 66.7 per 100 person-years. Meta-analyses estimated HCV prevalence at 0.7% among the general population (range 0-9.1%, 95% confidence interval (CI) 0.5-0.9%), 32.6% among PWID (range 9.5-70.0%, 95% CI 24.5-41.3%), and 2.3% among populations at intermediate risk (range 0.0-8.3%, 95% CI 1.3-3.7%). No data were available for other high risk populations such as hemodialysis, thalassemia, and hemophilia patients. HCV prevalence among the general population in Afghanistan is comparable to global levels. Data are needed for the level of infection among key clinical populations at high risk of infection. There is also an immediate need for expansion of harm reduction programs among PWID and prisoners. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
A hierarchical model for estimating change in American Woodcock populations
Sauer, J.R.; Link, W.A.; Kendall, W.L.; Kelley, J.R.; Niven, D.K.
2008-01-01
The Singing-Ground Survey (SGS) is a primary source of information on population change for American woodcock (Scolopax minor). We analyzed the SGS using a hierarchical log-linear model and compared the estimates of change and annual indices of abundance to a route regression analysis of SGS data. We also grouped SGS routes into Bird Conservation Regions (BCRs) and estimated population change and annual indices using BCRs within states and provinces as strata. Based on the hierarchical model?based estimates, we concluded that woodcock populations were declining in North America between 1968 and 2006 (trend = -0.9%/yr, 95% credible interval: -1.2, -0.5). Singing-Ground Survey results are generally similar between analytical approaches, but the hierarchical model has several important advantages over the route regression. Hierarchical models better accommodate changes in survey efficiency over time and space by treating strata, years, and observers as random effects in the context of a log-linear model, providing trend estimates that are derived directly from the annual indices. We also conducted a hierarchical model analysis of woodcock data from the Christmas Bird Count and the North American Breeding Bird Survey. All surveys showed general consistency in patterns of population change, but the SGS had the shortest credible intervals. We suggest that population management and conservation planning for woodcock involving interpretation of the SGS use estimates provided by the hierarchical model.
Sorsdahl, Katherine; Stein, Dan J; Myers, Bronwyn
2017-04-01
The Social Problem Solving Inventory-Revised Short-Form (SPSI-R:SF) has been used in several countries to identify problem-solving deficits among clinical and general populations in order to guide cognitive-behavioural interventions. Yet, very few studies have evaluated its psychometric properties. Three language versions of the questionnaire were administered to a general population sample comprising 1000 participants (771 English-, 178 Afrikaans- and 101 Xhosa-speakers). Of these participants, 210 were randomly selected to establish test-retest reliability (70 in each language). Principal component analysis was performed to examine the applicability of the factor structure of the original questionnaire to the South African data. Supplementary psychometric analyses were performed, including internal consistency and test-retest reliability. Collectively, results provide initial evidence of the reliability and validity of the SPSI-R:SF for the assessment of problem solving deficits in South Africa. Further studies that explore how the Afrikaans language version of the SPSI-R:SF can be improved and that establish the predictive validity of scores on the SPSI-R:SF are needed. © 2015 International Union of Psychological Science.
Brazilian normative data for the Short Form 36 questionnaire, version 2.
Laguardia, Josue; Campos, Monica Rodrigues; Travassos, Claudia; Najar, Alberto Lopes; Anjos, Luiz Antonio dos; Vasconcellos, Miguel Murat
2013-12-01
The study Pesquisa Dimensões Sociais das Desigualdades (PDSD) (Social Dimensions of Inequalities) involves 12,423 randomly selected Brazilian men and women aged 18 years old or more from urban and rural areas of the five Brazilian regions, and the information collected included the SF-36 as a measure of health-related quality of life. This provided a unique opportunity to develop age and gender-adjusted normative data for the Brazilian population. Brazilian men scored substantially higher than women on all eight domains and the two summary component scales of the SF-36. Brazilians scored less than their international counterparts on almost all of SF-36 domains and both summary component scales, except on general health status (US), pain (UK) and vitality (Australia, US and Canada). The differences in the SF-36 scores between age groups, genders and countries confirm that these Brazilian norms are necessary for comparative purposes. The data will be useful for assessing the health status of the general population and of patient populations, and the effect of interventions on health-related quality of life.
Prevalence Rates of Mental Disorders in Chilean Prisons
Mundt, Adrian P.; Alvarado, Rubén; Fritsch, Rosemarie; Poblete, Catalina; Villagra, Carolina; Kastner, Sinja; Priebe, Stefan
2013-01-01
Objective High rates of mental disorders have been reported for prison populations worldwide, particularly in low- and middle-income countries (LMICs). The present study aimed to establish prevalence rates of mental disorders in Chilean prisoners. Method A nationwide random sample of 1008 prisoners was assessed in 7 penal institutions throughout Chile. Twelve-month prevalence rates were established using the Composite International Diagnostic Interview (CIDI) and compared to the prevalence rates previously published for the general population. Results Prevalence rates were 12.2% (95% CI, 10.2-14.1) for any substance use disorder, 8.3% (6.6-10.0) for anxiety disorders, 8.1% (6.5-9.8) for affective disorders, 5.7% (4.4-7.1) for intermittent explosive disorders, 2.2% (1.4-3.2) for ADHD of the adult, and 0.8% (0.3-1.3) for non-affective psychoses. Significantly higher prevalence rates among prisoners as compared to the general population in Chile were seen for major depression (6.1% vs. 3.7% males, Z=2.58, p<0.05) and illicit drug use (3.3% vs. 0.6% males with drug abuse, Z=2.04, p<0.05; 2.6% vs. 0.1% females with drug abuse, Z=5.36, p<0.001; 3.4% vs. 1.1% males with drug dependence, Z=3.70; p<0.001). Dysthymia (6.5% vs. 15.6%, Z=-2.39, p<0.05), simple (3.3% vs. 11.5%, Z=-3.13, p<0.001) and social phobias (3.9% vs. 9.7%, Z=2.38, p<0.05) were significantly less frequent in the female prison population than in the general population. One-year prevalence rates of alcohol abuse (2.3% vs. 3.9%; Z=-2.04; p<0.05) and dependence (2.7% vs. 8.2%; Z=-5.24; p<0.001) were less prevalent in the male prison population than in the general population. Conclusions Service provision for prison populations in Chile should acknowledge high rates of depression and illicit drug use. Overall prevalence rates are lower than reported in other LMICs. Previous research in prison populations in LMICs might have overestimated prevalence rates of mental disorders. PMID:23894415
The valuation of the EQ-5D in Portugal.
Ferreira, Lara N; Ferreira, Pedro L; Pereira, Luis N; Oppe, Mark
2014-03-01
The EQ-5D is a preference-based measure widely used in cost-utility analysis (CUA). Several countries have conducted surveys to derive value sets, but this was not the case for Portugal. The purpose of this study was to estimate a value set for the EQ-5D for Portugal using the time trade-off (TTO). A representative sample of the Portuguese general population (n = 450) stratified by age and gender valued 24 health states. Face-to-face interviews were conducted by trained interviewers. Each respondent ranked and valued seven health states using the TTO. Several models were estimated at both the individual and aggregated levels to predict health state valuations. Alternative functional forms were considered to account for the skewed distribution of these valuations. The models were analyzed in terms of their coefficients, overall fit and the ability for predicting the TTO values. Random effects models were estimated using generalized least squares and were robust across model specification. The results are generally consistent with other value sets. This research provides the Portuguese EQ-5D value set based on the preferences of the Portuguese general population as measured by the TTO. This value set is recommended for use in CUA conducted in Portugal.
Texas dentists' attitudes toward the Dental Medicaid program.
Blackwelder, Aaron; Shulman, Jay D
2007-01-01
The purpose of this study was to report the attitudes of Texas dentists toward the Dental Medicaid program. A self-administered survey was mailed to all pediatric dentists and a random sample of general dentists. Surveys from 347 (69%) of 500 dentists (171 of 295 general dentists [58%] and 169 of 205 pediatric dentists [82%]) were returned. 57% of pediatric dentists and 29% of general dentists (P<.0001) treated at least 1 Medicaid patient in the past year. The major areas of dissatisfaction were: (1) broken appointments; (2) low reimbursement levels; and (3) patient noncompliance. This mirrors results from studies in Iowa, Louisiana, Ohio, Washington, and California. Both pediatric and general practitioners identified the following barriers to core for the Medicaid population: (1) low dental IQ; (2) few providers; and (3) no transportation. The major areas of dissatisfaction included both programmatic and patient-related factors. Attributes of the system (eg, lower reimbursement levels) are more modifiable than attributes of the patient population (eg, patient noncompliance and low dental IQ). Underfunding of dental Medicaid is endemic to all states studied in the literature. Providers, legislators, and government programs should target the programmatic problems with future efforts and funding.
[Natural selection associated with color vision defects in some population groups of Eurasia].
Evsiukov, A N
2014-01-01
Fitness coefficients and other quantitative parameters of selection associated with the generalized color blindness gene CB+ were obtained for three ethnogeographic population groups, including Belarusians from Belarus, ethnic populations of the Volga-Ural region, and ethnic populations of Siberia and the Far East of Russia. All abnormalities encoded by the OPN1LW and OPN1MW loci were treated as deviations from normal color perception. Coefficients were estimated from an approximation of the observed CB+ frequency distributions to the theoretical stationary distribution for the Wright island model. This model takes into account the pressure of migrations, selection, and random genetic drift, while the selection parameters are represented in the form of the distribution parameters. In the populations of Siberia and Far East, directional selection in favor of normal color vision and the corresponding allele CB- was observed. In the Belarusian and ethnic populations of the Volga-Ural region, stabilizing selection was observed. The selection intensity constituted 0.03 in the Belarusian; 0.22 in the ethnic populations of the Volga-Ural region; and 0.24 in ethnic populations of Siberia and Far East.
Eliassen, Knut Eirik; Hjetland, Reidar; Reiso, Harald; Lindbæk, Morten; Tschudi-Madsen, Hedda
2017-03-01
Promptly treated erythema migrans (EM) has good prognosis. However, some patients report persistent symptoms. Do patients with EM have more symptoms than the general population? We describe individual symptoms and general function in EM-patients at time of diagnosis and one year after treatment. Prospective study with 1-year follow up after treatment. Questionnaires included a modified version of the Subjective Health Complaints Inventory, comprising three additional Lyme borreliosis (LB) related symptoms. General function was assessed using a five-point scale modified from the COOP/WONCA charts. Norwegian general practice. A total of 188 patients were included in a randomized controlled trial comparing three antibiotic regimens for EM, of whom 139 had complete data for this study. Individual symptoms, symptom load and general function. Mild symptoms were common, reported by 84.9% at baseline and by 85.6% at follow-up. At baseline, patients reported a mean of 5.4 symptoms, compared with 6.2 after one year. Severely bothersome symptoms and severely impaired general function were rare. Tiredness was the most reported symptom both at baseline and at follow-up. Palsy (other than facial) was the least reported symptom, but the only one with a significant increase. However, this was not associated to the EM. The symptom load was comparable to that reported in the general population. We found an increase in symptom load at follow-up that did not significantly affect general function. Monitoring patients' symptom loads prior to treatment reduce the probability of attributing follow-up symptoms to LB. Key points Erythema migrans has a good prognosis.Patients treated for erythema migrans have a slight increase in symptom load one year after treatment. This increase does not affect general function. The levels of subjective health complaints in patients treated for erythema migrans are comparable to the background population.
Jilani, Tanveer; Azam, Iqbal; Moiz, Bushra; Mehboobali, Naseema; Perwaiz Iqbal, Mohammad
2015-01-01
Hemoglobin levels slightly below the lower limit of normal are common in adults in the general population in developing countries. A few human studies have suggested the use of antioxidant vitamins in the correction of mild anemia. The objective of the present study was to investigate the association of vitamin E supplementation in mildly anemic healthy adults with post-supplemental blood hemoglobin levels in the general population of Karachi, Pakistan. In a single-blinded and placebo-controlled randomized trial, 124 mildly anemic subjects from the General Practitioners' Clinics and personnel of the Aga Khan University were randomized into intervention (n = 82) and control (n = 42) group. In the intervention group, each subject was given vitamin E (400 mg) everyday for a period of three months, while control group subjects received a placebo. Eighty six subjects completed the trial. Fasting venous blood was collected at baseline and after three months of supplementation. Hemoglobin levels and serum/plasma concentrations of vitamin E, vitamin B12, folate, ferritin, serum transferrin receptor (sTfR), glucose, total cholesterol, triglycerides, LDL-cholesterol, HDL-cholesterol, creatinine, total-antioxidant-status and erythropoietin were measured and analyzed using repeated measures ANOVA and multiple linear regression. The adjusted regression coefficients (β) and standard error [SE(β)] of the significant predictors of post-supplemental hemoglobin levels were serum concentration of vitamin E (0.983[0.095]), gender (- 0.656[0.244]), sTfR (- 0.06[0.02]) and baseline hemoglobin levels (0.768[0.077]). The study showed a positive association between vitamin E supplementation and enhanced hemoglobin levels in mildly anemic adults.
Prevalence and occupational associations of neck pain in the British population.
Palmer, K T; Walker-Bone, K; Griffin, M J; Syddall, H; Pannett, B; Coggon, D; Cooper, C
2001-02-01
This study determined the prevalence of neck pain and its relation to occupation and occupational activities in the general population. A questionnaire was mailed to 21 201 subjects aged 16-64 years, randomly selected from the patient registers of general practices in England, Scotland, and Wales, and to 993 subjects randomly selected from pay records of the armed services. Information was collected on occupation, workplace physical activities, neck pain in the past week and year, headaches, and feelings of tiredness or stress. Associations were explored by logistic regression, the resultant odds ratios being converted to prevalence ratios (PR). Among 12907 respondents, 4348 and 2528 reported neck pain in past year (1421 with pain interfering with normal activities) and week, respectively. Symptoms were the most prevalent among male construction workers [past week and year 24% and 38% (pain interfering with activities 11%), respectively], followed by nurses, armed services members, and the unemployed. Generally the age-standardized prevalence of neck pain varied little by occupation. Work with arms above the shoulders for >1 hours/day was associated with a significant excess of symptoms [PR 1.3-1.7 (women) and 1.2-1.4 (men)], but no associations existed for typing, lifting, vibratory tool use, or professional driving. Stronger neck-pain associations were found with frequent headaches (PR 2.3-2.8) and frequent tiredness or stress (PR 2.2-2.5) than with occupational activities. The data provide evidence against a strong association between neck pain and the examined occupational physical activities. They suggest that psychosocial factors may be more important.
Euser, Saskia; Alink, Lenneke R A; Tharner, Anne; van Ijzendoorn, Marinus H; Bakermans-Kranenburg, Marian J
2013-11-01
We investigated the 2010 year prevalence of child sexual abuse (CSA) in residential and foster care and compared it with prevalence rates in the general population. We used two approaches to estimate the prevalence of CSA. First, 264 professionals working in residential or foster care (sentinels) reported CSA for the children they worked with (N = 6,281). Second, 329 adolescents staying in residential or foster care reported on their own experiences with CSA. Sentinels and adolescents were randomly selected from 82 Dutch out-of-home care facilities. We found that 3.5 per 1,000 children had been victims of CSA based on sentinel reports. In addition, 58 per 1,000 adolescents reported having experienced CSA. Results based on both sentinel report and self-report revealed higher prevalence rates in out-of-home care than in the general population, with the highest prevalence in residential care. Prevalence rates in foster care did not differ from the general population. According to our findings, children and adolescents in residential care are at increased risk of CSA compared to children in foster care. Unfortunately, foster care does not fully protect children against sexual abuse either, and thus its quality needs to be further improved.
Mashour, George A; Tremper, Kevin K; Avidan, Michael S
2009-11-05
The incidence of intraoperative awareness with explicit recall is 1-2/1000 cases in the United States. The Bispectral Index monitor is an electroencephalographic method of assessing anesthetic depth that has been shown in one prospective study to reduce the incidence of awareness in the high-risk population. In the B-Aware trial, the number needed to treat in order to prevent one case of awareness in the high-risk population was 138. Since the number needed to treat and the associated cost of treatment would be much higher in the general population, the efficacy of the Bispectral Index monitor in preventing awareness in all anesthetized patients needs to be clearly established. This is especially true given the findings of the B-Unaware trial, which demonstrated no significant difference between protocols based on the Bispectral Index monitor or minimum alveolar concentration for the reduction of awareness in high risk patients. To evaluate efficacy in the general population, we are conducting a prospective, randomized, controlled trial comparing the Bispectral Index monitor to a non-electroencephalographic gauge of anesthetic depth. The total recruitment for the study is targeted for 30,000 patients at both low and high risk for awareness. We have developed a novel algorithm that is capable of real-time analysis of our electronic perioperative information system. In one arm of the study, anesthesia providers will receive an electronic page if the Bispectral Index value is >60. In the other arm of the study, anesthesia providers will receive a page if the age-adjusted minimum alveolar concentration is <0.5. Our minimum alveolar concentration algorithm is sensitive to both inhalational anesthetics and intravenous sedative-hypnotic agents. Awareness during general anesthesia is a persistent problem and the role of the Bispectral Index monitor in its prevention is still unclear. The Michigan Awareness Control Study is the largest prospective trial of awareness prevention ever conducted. Clinical Trial NCT00689091.
Bai, Chunxue; Ichinose, Masakazu; Lee, Sang Haak; Lee, Kwan Ho; Jöns, Olaf; Bothner, Ulrich; Zhao, Yihua; Buhl, Roland
2017-01-01
While the efficacy and safety of combined tiotropium and olodaterol in patients with COPD was established in a large clinical trial program, it is important to assess whether clinical data can be applied to geographic patient groups, particularly for East Asian patients who may have a different phenotypic profile to the global trial population. This study aimed to compare the lung function and safety profiles of tiotropium/olodaterol and monocomponents in East Asian and global populations from the TONADO ® trials. In the replicate, double-blind, parallel-group, active-controlled, randomized, 52-week, Phase III TONADO studies, patients received tiotropium/olodaterol, tiotropium, or olodaterol. We assessed the forced expiratory volume in 1 second (FEV 1 ) area under the curve from 0 to 3 hours (AUC 0-3 ) response and trough FEV 1 response at 24 weeks for the approved doses, tiotropium/olodaterol 5/5 μg, tiotropium 5 μg, and olodaterol 5 μg. Treatment-emergent adverse events were recorded throughout treatment and ≤21 days after study medication. In the East Asian population, 1,152 patients were randomized (5,163 overall). After 24 weeks, FEV 1 AUC 0-3 and trough FEV 1 responses were greater ( P <0.0001) with tiotropium/olodaterol 5/5 μg in both populations versus tiotropium or olodaterol. The East Asian population showed slightly greater trough FEV 1 treatment differences between tiotropium/olodaterol 5/5 μg and tiotropium compared to the overall population. Generally, no increase in adverse events was seen with tiotropium/olodaterol 5/5 μg compared to tiotropium and olodaterol in either population. The efficacy and safety profile of tiotropium/olodaterol 5/5 μg has been demonstrated for both East Asian and global populations.
Oral cancer awareness in Spain: A pilot study.
Varela-Centelles, P; Estany-Gestal, A; Bugarín-González, R; Seoane-Romero, J M
2018-03-01
To investigate the level of oral cancer knowledge and awareness in a Spanish general population. A cross-sectional study using an anonymous questionnaire applied in the community to randomly selected laypersons. Sample size for the general population was determined by quota sampling, resulting in 1,041 individuals. A total of 1,707 pedestrians were approached (response: 61%). When the participants were asked about what cancers had they heard about (up to ten), oral cancer was mentioned in first place by 2% of the sample and by 22% in any order. When specifically asked about oral cancer, the percentage of interviewees who were familiar with it raised to 72%. Participants were also asked about the main signs or symptoms of oral cancer, and the most frequently (22%) mentioned as the first warning sign was a non-healing ulcer. Tobacco smoking generally was recognised as the most important (57%) risk factor for oral cancer. This pilot study revealed a low awareness of oral cancer, and a poor knowledge of its signs and symptoms and risk factors. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.
Evins, A Eden; Hoeppner, Susanne S; Schoenfeld, David A; Hoeppner, Bettina B; Cather, Corinne; Pachas, Gladys N; Cieslak, Kristina M; Maravic, Melissa Culhane
2017-05-01
To compare the effect of maintenance pharmacotherapy on sustained abstinence rates between recently abstinent smokers with schizophrenia and bipolar disorder (SBD) and general population smokers without psychiatric illness. We performed a person-level, pooled analysis of two randomized controlled trials of maintenance varenicline, conducted in adult smokers with SBD and general population smokers, controlling for severity of dependence. Smokers abstinent after 12-weeks of open varenicline treatment were randomly assigned to ≥12-weeks maintenance varenicline or identical placebo. In those assigned to maintenance placebo, the abstinence rate at week-24 was lower in those with SBD than for those without psychiatric illness (29.4±1.1% vs. 61.8±0.4%, OR:0.26, 95% CI: 0.13, 0.52, p<0.001). In smokers assigned to maintenance pharmacotherapy, however, there was no effect of diagnosis on abstinence rates at week-24 (87.2±0.8% vs. 81.9±0.2%, OR: 1.68, 95% CI: 0.53, 5.32, p=0.38). Time to first lapse was shortest in those with SBD assigned to maintenance placebo (Q1=12days, 95%CI: 4, 16), longer in those without psychiatric illness assigned to maintenance placebo (Q1=17days, 95%CI: 17, 29), still longer in general-population smokers assigned to maintenance varenicline (Q1=88, 95% CI:58,91, and longest in those with SBD who received maintenance varenicline (Q1>95days, 95%CI:non-est), (Χ 2 3df =96.99, p<0.0001; all pairwise comparisons p<0.001). Following a standard 12-week course of pharmacotherapy, people with schizophrenia and bipolar disorder were more likely to relapse to smoking without maintenance varenicline treatment. Maintenance pharmacotherapy could improve longer-term tobacco abstinence rates and reduce known smoking-related health disparities in those with SMI. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Meyer, Christian; Ulbricht, Sabina; Haug, Severin; Broda, Anja; Bischof, Gallus; Rumpf, Hans-Jürgen; John, Ulrich
2016-09-01
This study examined the long-term efficacy of individualized counseling letters that targeted either smoking abstinence or reducing the number of cigarettes smoked per day to promote future cessation. A nationwide random-digit-dialing telephone sample was used to identify smokers from the general adult population (participation proportion: 54.5%). In total, 1462 participants (48% female) who did not intend to quit within the next six months and who smoked ten or more cigarettes a day were randomized to one of two intervention groups or an assessment-only control condition. The interventions consisted of three tailored letters that were sent after baseline and follow-up assessments after three and six months. Follow-up data on smoking status were provided by 82% and 77% of the participants 12 and 24 months after study inclusion, respectively. Generalized estimation equation (GEE) models adjusted for potential baseline confounders and multiple imputation of missing follow-up data were used to estimate intervention effects. At 24-month follow-up prevalence of 7-day point abstinence was 8.4%, 12.9% and 14.7% in the control, abstinence intervention and reduction intervention condition, which corresponds to a number needed to treat of 22 (95%-CI: 11-707) and 16 (95%-CI: 9-53). Adjusted GEE analyses revealed that the smoking reduction intervention (ORadj=2.3, p<0.01) but not the abstinence intervention (ORadj=1.4, p=0.20) increased the odds of 6-month prolonged abstinence compared with the control condition. No significant differences appear when directly comparing both intervention groups. Smoking reduction should be considered as an alternative intervention goal for smokers who are unable or unwilling to quit. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Waldman, Linda; Ahmed, Tanvir; Scott, Nigel; Akter, Shahinoor; Standing, Hilary; Rasheed, Sabrina
2018-03-20
Information and Communications Technologies (ICTs) which enable people to access, use and promote health information through digital technology, promise important health systems innovations which can challenge gatekeepers' control of information, through processes of disintermediation. College students, in pursuit of sexual and reproductive health (SRH) information, are particularly affected by gatekeeping as strong social and cultural norms restrict their access to information and services. This paper examines mobile phone usage for obtaining health information in Mirzapur, Bangladesh. It contrasts college students' usage with that of the general population, asks whether students are using digital technologies for health information in innovative ways, and examines how gender affects this. This study relies on two surveys: a 2013-2014 General Survey that randomly sampled 854 households drawn from the general population and a 2015 Student Survey that randomly sampled 436 students from two Mirzapur colleges. Select focus group discussions and in-depth interviews were undertaken with students. Icddr,b's Ethical Review Board granted ethical clearance. The data show that Mirzapur's college students are economically relatively well positioned, more likely to own mobile and smart phones, and more aware of the internet than the general population. They are interested in health information and use phones and computers to access information. Moreover, they use digital technology to share previously-discreet information, adding value to that information and bypassing former gatekeepers. But access to health information is not entirely unfettered, affecting male and female students differently, and powerful gatekeepers, both old and new, can still control sources of information. Personal searches for SRH and the resultant online information shared through discrete, personal face-to-face discussions has some potential to challenge social norms. This is particularly so for women students, as sharing information may enable them to bypass gatekeepers and make decisions about reproduction. This suggests that digital health information seeking may be exercising a disruptive effect within the health sector. However, the extent of this disruption may depend, not on students' mobile phone usage, but on the degree to which powerful new gatekeepers are able to retain control over and market SRH information through students' peer-to-peer sharing.
Statistical dynamics of regional populations and economies
NASA Astrophysics Data System (ADS)
Huo, Jie; Wang, Xu-Ming; Hao, Rui; Wang, Peng
Quantitative analysis of human behavior and social development is becoming a hot spot of some interdisciplinary studies. A statistical analysis on the population and GDP of 150 cities in China from 1990 to 2013 is conducted. The result indicates the cumulative probability distribution of the populations and that of the GDPs obeying the shifted power law, respectively. In order to understand these characteristics, a generalized Langevin equation describing variation of population is proposed, which is based on the correlations between population and GDP as well as the random fluctuations of the related factors. The equation is transformed into the Fokker-Plank equation to express the evolution of population distribution. The general solution demonstrates a transition of the distribution from the normal Gaussian distribution to a shifted power law, which suggests a critical point of time at which the transition takes place. The shifted power law distribution in the supercritical situation is qualitatively in accordance with the practical result. The distribution of the GDPs is derived from the well-known Cobb-Douglas production function. The result presents a change, in supercritical situation, from a shifted power law to the Gaussian distribution. This is a surprising result-the regional GDP distribution of our world will be the Gaussian distribution one day in the future. The discussions based on the changing trend of economic growth suggest it will be true. Therefore, these theoretical attempts may draw a historical picture of our society in the aspects of population and economy.
Hilton, Joan F.; Wright, Catherine C.; Arnold, Benjamin F.; Saha, Sona; Wade, Timothy J.; Scott, James; Eisenberg, Joseph N.S.
2009-01-01
Objectives. We estimated the relative rate of highly credible gastrointestinal illness (HCGI) per year associated with active versus sham household water filtration devices among older adults in a community receiving tap water meeting current US standards. Methods. We conducted a randomized, triple-blinded, crossover trial in 714 households (988 individuals), which used active and sham water filtration devices for 6 months each. We estimated the annual incidence rate ratio of HCGI episodes and the longitudinal prevalence ratio of HCGI days at population and individual levels with a generalized estimating equation (GEE) and generalized linear mixed models (GLMMs), respectively, adjusted for covariates associated with outcome. Results. The incidence rate ratios (active versus sham) were 0.88 (95% confidence interval [CI] = 0.77, 1.00) and 0.85 (95% CI = 0.76, 0.94) HCGI episodes per year estimated by GEE and GLMM models, respectively. The corresponding longitudinal prevalence ratios were 0.88 (95% CI = 0.74, 1.05) and 0.84 (95% CI = 0.78, 0.90) HCGI days per person per year. Conclusions. We observed reductions in population- and individual-level measures of HCGI associated with use of the active filtration device. These findings suggest the need for further research on the impact of drinking water on the health of sensitive subpopulations. PMID:19762663
Briot, Karine; Paternotte, Simon; Kolta, Sami; Eastell, Richard; Felsenberg, Dieter; Reid, David M.; Glüer, Claus-C.; Roux, Christian
2013-01-01
Purposes The aim of this study was to analyse how well FRAX® predicts the risk of major osteoporotic and vertebral fractures over 6 years in postmenopausal women from general population. Patients and methods The OPUS study was conducted in European women aged above 55 years, recruited in 5 centers from random population samples and followed over 6 years. The population for this study consisted of 1748 women (mean age 74.2 years) with information on incident fractures. 742 (43.1%) had a prevalent fracture; 769 (44%) and 155 (8.9%) of them received an antiosteoporotic treatment before and during the study respectively. We compared FRAX® performance with and without bone mineral density (BMD) using receiver operator characteristic (ROC) c-statistical analysis with ORs and areas under receiver operating characteristics curves (AUCs) and net reclassification improvement (NRI). Results 85 (4.9%) patients had incident major fractures over 6 years. FRAX® with and without BMD predicted these fractures with an AUC of 0.66 and 0.62 respectively. The AUC were 0.60, 0.66, 0.69 for history of low trauma fracture alone, age and femoral neck (FN) BMD and combination of the 3 clinical risk factors, respectively. FRAX® with and without BMD predicted incident radiographic vertebral fracture (n = 65) with an AUC of 0.67 and 0.65 respectively. NRI analysis showed a significant improvement in risk assignment when BMD is added to FRAX®. Conclusions This study shows that FRAX® with BMD and to a lesser extent also without FN BMD predict major osteoporotic and vertebral fractures in the general population. PMID:24386199
Sevillano, David; Mínguez, Cristina; Sánchez, Alicia; Sánchez-Reyes, Alberto
2016-01-01
To obtain specific margin recipes that take into account the dosimetric characteristics of the treatment plans used in a single institution. We obtained dose-population histograms (DPHs) of 20 helical tomotherapy treatment plans for prostate cancer by simulating the effects of different systematic errors (Σ) and random errors (σ) on these plans. We obtained dosimetric margins and margin reductions due to random errors (random margins) by fitting the theoretical results of coverages for Gaussian distributions with coverages of the planned D99% obtained from the DPHs. The dosimetric margins obtained for helical tomotherapy prostate treatments were 3.3 mm, 3 mm, and 1 mm in the lateral (Lat), anterior-posterior (AP), and superior-inferior (SI) directions. Random margins showed parabolic dependencies, yielding expressions of 0.16σ(2), 0.13σ(2), and 0.15σ(2) for the Lat, AP, and SI directions, respectively. When focusing on values up to σ = 5 mm, random margins could be fitted considering Gaussian penumbras with standard deviations (σp) equal to 4.5 mm Lat, 6 mm AP, and 5.5 mm SI. Despite complex dose distributions in helical tomotherapy treatment plans, we were able to simplify the behaviour of our plans against treatment errors to single values of dosimetric and random margins for each direction. These margins allowed us to develop specific margin recipes for the respective treatment technique. The method is general and could be used for any treatment technique provided that DPHs can be obtained. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
Petráš, Marek; Adámková, Věra
2015-11-17
To assess the impact of a quadrivalent human papillomavirus vaccine (4HPV) in women at increased risk of genital warts (GWs) acquisition. The study was conducted using a population-based cross-sectional survey of 19,199 women aged 16 to 40 years randomly chosen from the general population in the Czech Republic between January 2013 and March 2014. A total of 1086 women reported having received the 4HPV vaccine. The vaccine's effectiveness was estimated not only in the general population of women but also in those at increased risk due to having a sexual partner with GWs or prior GWs history. The acquisition of GWs was dramatically reduced by 90.6% (80.1-95.6%) in immunised women at least one year after the completion of the 4HPV vaccination in comparison with unimmunised women. Recurrent GWs prevalences of 1.1% (95% CI, 0.0-5.9) and 10.9% (95% CI, 9.1-12.9) in immunised and unimmunised women with prior GWs history, respectively, resulted in a vaccine effectiveness of 89.0% (38.6-98.0%). The notably strong protective effect of 4HPV immunisation in women who had a sexual partner with GWs was demonstrated by a very low age-adjusted odds ratio of 0.02 (95% CI 0.01-0.10) in contrast to unimmunised women. To lower the chance of genital warts acquisition in the general population and in populations at increased risk, only current 4HPV or incoming 9HPV vaccination should be recommended to provide effective protection. Copyright © 2015 Elsevier Ltd. All rights reserved.
Gibson, Laura; Brennan, Emily; Momjian, Ani; Shapiro-Luft, Dina; Seitz, Holli; Cappella, Joseph N
2015-08-01
Population-level communication interventions, such as graphic warning labels (GWLs) on cigarette packs, have the potential to reduce or exacerbate tobacco-related health disparities depending on their effectiveness among disadvantaged sub-populations. This study evaluated the likely impact of nine GWLs proposed by the US Food and Drug Administration on (1) African American and (2) Hispanic smokers, who disproportionately bear the burden of tobacco-related illness, and (3) low education smokers, who have higher smoking rates. Data were collected online from current smokers randomly assigned to see GWLs (treatment) or the current text-only warning labels (control). Participants were stratified by age (18-25; 26+) in each of four groups: general population (n = 1246), African Americans (n = 1200), Hispanics (n = 1200), and low education (n = 1790). We tested the effectiveness of GWLs compared to text-only warning labels using eight outcomes that are predictive of quitting intentions or behaviors including negative emotion, intentions to hold back from smoking, intentions to engage in avoidance behaviors, and intentions to quit. Across all outcomes, GWLs were significantly more effective than text-only warning labels more often than expected by chance. Results suggested that African Americans, Hispanics and smokers with low education did not differ from the general population of smokers in their reactions to any of the nine individual GWLs. The nine GWLs were similarly effective for disadvantaged sub-populations and the general population of smokers. Implementation of GWLs is therefore unlikely to reduce or exacerbate existing tobacco-related health disparities, but will most likely uniformly increase intentions and behaviors predictive of smoking cessation. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Brennan, Emily; Momjian, Ani; Shapiro-Luft, Dina; Seitz, Holli; Cappella, Joseph N.
2015-01-01
Introduction: Population-level communication interventions, such as graphic warning labels (GWLs) on cigarette packs, have the potential to reduce or exacerbate tobacco-related health disparities depending on their effectiveness among disadvantaged sub-populations. This study evaluated the likely impact of nine GWLs proposed by the US Food and Drug Administration on (1) African American and (2) Hispanic smokers, who disproportionately bear the burden of tobacco-related illness, and (3) low education smokers, who have higher smoking rates. Methods: Data were collected online from current smokers randomly assigned to see GWLs (treatment) or the current text-only warning labels (control). Participants were stratified by age (18–25; 26+) in each of four groups: general population (n = 1246), African Americans (n = 1200), Hispanics (n = 1200), and low education (n = 1790). We tested the effectiveness of GWLs compared to text-only warning labels using eight outcomes that are predictive of quitting intentions or behaviors including negative emotion, intentions to hold back from smoking, intentions to engage in avoidance behaviors, and intentions to quit. Results: Across all outcomes, GWLs were significantly more effective than text-only warning labels more often than expected by chance. Results suggested that African Americans, Hispanics and smokers with low education did not differ from the general population of smokers in their reactions to any of the nine individual GWLs. Conclusions: The nine GWLs were similarly effective for disadvantaged sub-populations and the general population of smokers. Implementation of GWLs is therefore unlikely to reduce or exacerbate existing tobacco-related health disparities, but will most likely uniformly increase intentions and behaviors predictive of smoking cessation. PMID:26180214
Mundell, Benjamin F; Kremers, Hilal Maradit; Visscher, Sue; Hoppe, Kurtis M; Kaufman, Kenton R
2016-08-01
Prior studies have identified age as a factor in determining an individual's likelihood of receiving a prosthesis following a lower limb amputation. These studies are limited to specific subsets of the general population and are unable to account for preamputation characteristics within their study populations. Our study seeks to determine the effect of preamputation characteristics on the probability of receiving a prosthesis for the general population in the United States. To identify preamputation characteristics that predict of the likelihood of receiving a prosthesis following an above-knee amputation. A retrospective, population-based cohort study. Olmsted County, Minnesota (2010 population: 144,248). Individuals (n = 93) over the age of 18 years who underwent an above-knee amputation, that is, knee disarticulation or transfemoral amputation, while residing in Olmsted County, MN, between 1987 and 2013. Characteristics affecting the receipt of a prosthesis were analyzed using a logistic regression and a random forest algorithm for classification trees. Preamputation characteristics included age, gender, amputation etiology, year of amputation, mobility, cognitive ability, comorbidities, and time between surgery and the prosthesis decision. The association of preamputation characteristics with the receipt of a prosthesis following an above-knee amputation. Twenty-four of the participants received a prosthesis. The odds of receiving a prosthesis were almost 30 times higher in those able to walk independently prior to an amputation relative to those who could not walk independently. A 10-year increase in age was associated with a 53.8% decrease in the likelihood of being fit for a prosthesis (odds ratio = 0.462, P =.030). Time elapsed between surgery and the prosthesis decision was associated with a rise in probability of receiving a prosthesis for the first 3 months in the random forest algorithm. No other observed characteristics were associated with receipt of a prosthesis. The association of preamputation mobility and age with the likelihood of being fit for a prosthesis is well understood. The effect of age, after controlling for confounders, still persists and is associated with the likelihood of being fit for a prosthesis. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Information technology and medical missteps: evidence from a randomized trial.
Javitt, Jonathan C; Rebitzer, James B; Reisman, Lonny
2008-05-01
We analyze the effect of a decision support tool designed to help physicians detect and correct medical "missteps". The data comes from a randomized trial of the technology on a population of commercial HMO patients. The key findings are that the new information technology lowers average charges by 6% relative to the control group. This reduction in resource utilization was the result of reduced in-patient charges (and associated professional charges) for the most costly patients. The rate at which identified issues were resolved was generally higher in the study group than in the control group, suggesting the possibility of improvements in care quality along measured dimensions and enhanced diffusion of new protocols based on new clinical evidence.
Mean-Potential Law in Evolutionary Games
NASA Astrophysics Data System (ADS)
Nałecz-Jawecki, Paweł; Miekisz, Jacek
2018-01-01
The Letter presents a novel way to connect random walks, stochastic differential equations, and evolutionary game theory. We introduce a new concept of a potential function for discrete-space stochastic systems. It is based on a correspondence between one-dimensional stochastic differential equations and random walks, which may be exact not only in the continuous limit but also in finite-state spaces. Our method is useful for computation of fixation probabilities in discrete stochastic dynamical systems with two absorbing states. We apply it to evolutionary games, formulating two simple and intuitive criteria for evolutionary stability of pure Nash equilibria in finite populations. In particular, we show that the 1 /3 law of evolutionary games, introduced by Nowak et al. [Nature, 2004], follows from a more general mean-potential law.
Nidich, Sanford; Seng, Angela; Compton, Blaze; O’Connor, Tom; Salerno, John W; Nidich, Randi
2017-01-01
Context: Compared with the general population, trauma experiences are higher among incarcerated women. Objective: To evaluate the effects of Transcendental Meditation (TM) on trauma symptoms in female offenders. Design: Twenty-two inmates at the Coffee Creek Correctional Facility in Wilsonville, OR, with at least 4 months left of incarceration were enrolled in this randomized controlled pilot study. Subjects were randomly assigned to either the TM group (n = 11) or a wait-list control group (n = 11). Main Outcome Measures: Subjects were measured at baseline and 4-month posttest using the Posttraumatic Stress Disorder Checklist-Civilian version (PCL-C; primary outcome) with intrusive thoughts, avoidance, and hyperarousal subscales (secondary outcomes). Twenty of the subjects (10 in each group) took part in their treatment assignment and completed posttesting. Results: Significant reductions were found on total trauma (p < 0.036), intrusive thoughts (p < 0.026), and hyperarousal (p < 0.043) on the PCL-C. Effect sizes ranged from 0.65 to 0.99 for all variables. Eighty-one percent of the TM subjects were compliant with their program. Conclusion: The results of this study indicate feasibility of the TM program in a female prison population and suggest that TM may be an effective tool for decreasing trauma symptoms. Future large-scale research is warranted. PMID:28333611
Nidich, Sanford; Seng, Angela; Compton, Blaze; O'connor, Tom; Salerno, John W; Nidich, Randi
2017-01-01
Compared with the general population, trauma experiences are higher among incarcerated women. To evaluate the effects of Transcendental Meditation (TM) on trauma symptoms in female offenders. Twenty-two inmates at the Coffee Creek Correctional Facility in Wilsonville, OR, with at least 4 months left of incarceration were enrolled in this randomized controlled pilot study. Subjects were randomly assigned to either the TM group (n = 11) or a wait-list control group (n = 11). Subjects were measured at baseline and 4-month posttest using the Posttraumatic Stress Disorder Checklist-Civilian version (PCL-C; primary outcome) with intrusive thoughts, avoidance, and hyperarousal subscales (secondary outcomes). Twenty of the subjects (10 in each group) took part in their treatment assignment and completed posttesting. Significant reductions were found on total trauma (p < 0.036), intrusive thoughts (p < 0.026), and hyperarousal (p < 0.043) on the PCL-C. Effect sizes ranged from 0.65 to 0.99 for all variables. Eighty-one percent of the TM subjects were compliant with their program. The results of this study indicate feasibility of the TM program in a female prison population and suggest that TM may be an effective tool for decreasing trauma symptoms. Future large-scale research is warranted.
Case Presentations Demonstrating Periodontal Treatment Variation: PEARL Network.
Curro, Frederick A; Grill, Ashley C; Matthews, Abigail G; Martin, John; Kalenderian, Elisabeth; Craig, Ronald G; Naftolin, Frederick; Thompson, Van P
2015-06-01
Variation in periodontal terminology can affect the diagnosis and treatment plan as assessed by practicing general dentists in the Practitioners Engaged in Applied Research and Learning (PEARL) Network. General dentists participating in the PEARL Network are highly screened, credentialed, and qualified and may not be representative of the general population of dentists. Ten randomized case presentations ranging from periodontal health to gingivitis, to mild, moderate, and severe periodontitis were randomly presented to respondents. Descriptive comparisons were made between these diagnosis groups in terms of the treatment recommendations following diagnosis. PEARL practitioners assessing periodontal clinical scenarios were found to either over- or under-diagnose the case presentations, which affected treatment planning, while the remaining responses concurred with respect to the diagnosis. The predominant diagnosis was compared with that assigned by two practicing periodontists. There was variation in treatment based on the diagnosis for gingivitis and the lesser forms of periodontitis. Data suggests that a lack of clarity of periodontal terminology affects both diagnosis and treatment planning, and terminology may be improved by having diagnosis codes, which could be used to assess treatment outcomes. This article provides data to support best practice for the use of diagnosis coding and integration of dentistry with medicine using ICD-10 terminology.
Sample size of the reference sample in a case-augmented study.
Ghosh, Palash; Dewanji, Anup
2017-05-01
The case-augmented study, in which a case sample is augmented with a reference (random) sample from the source population with only covariates information known, is becoming popular in different areas of applied science such as pharmacovigilance, ecology, and econometrics. In general, the case sample is available from some source (for example, hospital database, case registry, etc.); however, the reference sample is required to be drawn from the corresponding source population. The required minimum size of the reference sample is an important issue in this regard. In this work, we address the minimum sample size calculation and discuss related issues. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kastner, S.O.; Bhatia, A.K.
A generalized method for obtaining individual level population ratios is used to obtain relative intensities of extreme ultraviolet Fe XV emission lines in the range 284 --500 A, which are density dependent for electron densities in the tokamak regime or higher. Four lines in particular are found to attain quite high intensities in the high-density limit. The same calculation provides inelastic contributions to linewidths. The method connects level populations and level widths through total probabilities t/sub i/j, related to ''taboo'' probabilities of Markov chain theory. The t/sub i/j are here evaluated for a real atomic system, being therefore of potentialmore » interest to random-walk theorists who have been limited to idealized systems characterized by simplified transition schemes.« less
Homelessness in the state and federal prison population.
Greenberg, Greg A; Rosenheck, Robert A
2008-01-01
This study sought to investigate the rates and correlates of homelessness (i.e. living on the street or in a homeless shelter), including mental illness, among US adult state and federal prison inmates (ASFPIs). Data from a national survey of ASFPIs based on a random sampling survey (N = 17,565) were used to compare the homelessness rate among AFSPIs with that in the general population. Logistic regression was then used to examine the association of homelessness among ASFPIs with factors including symptoms, treatment of mental illness, previous criminal justice involvement, specific crimes, and demographic characteristics. Nine percent of ASFPIs reported an episode of homelessness in the year prior to arrest, 4-6 times the estimated rate in the general US adult population after allowing for age, race/ethnicity, and gender. In comparison to other inmates, these homeless inmates were more likely to be currently incarcerated for a property crime, but also to have had previous criminal justice system involvement for both property and violent crimes, to suffer from mental health and/or substance abuse problems, and to be more likely to have been unemployed and with a low income. Recent homelessness is far more common among ASFPIs than the general population. Prior incarceration, mental illness, substance abuse and disadvantageous socio-demographic characteristics were all found to be associated with homelessness among prison inmates, suggesting that there are several important factors in addition to efforts to survive with limited resources through criminal acts that influence the rates of homelessness among incarcerated individuals.
Johnsen, R; Holtedahl, K A
1997-04-20
In a survey of task profiles in General Practice 164 general practitioners (GPs) in Norway, 51% of a random sample, answered a questionnaire and 147 doctors also kept a diary on their practice for one week, specifying their activities throughout the day. Men reported working more hours per week than women, and practitioners working on a fee-for-service basis had more consultations than colleagues on a fixed salary. Fixed salary GPs spent more time on emergency service. More women than men had part time jobs. The number of GPs has doubled from 1978 to 1993, but the total workload for a GP is approximately the same. The population must have doubled its consumption of primary health care services over this 15 year period.
Aburizik, Arwa; Dindo, Lilian; Kaboli, Peter; Charlton, Mary; Dawn, Klein; Turvey, Carolyn
2013-11-01
Depression in medically ill patients occurs at twice the rate found in the general population. Though pharmacologic and psychotherapeutic interventions for depression are effective, response to treatment and access to care are barriers for this population. A multidimensional telehealth intervention was designed to focus on these barriers by delivering a phone based intervention that addressed managing one's illness and coping emotionally. Veterans with diabetes, hypertension, or chronic pain and depressive symptoms were randomized to one of three conditions: Usual Care (n=23), Illness Management Only (n=31), or Combined Psychotherapy and Illness Management (n=29). Those randomized to the Combined or Illness Management Only intervention group received 10 phone visits. Veterans in the Combined group received all aspects of the illness management program plus a manualized depression intervention. Subjects completed assessments at baseline, week 5, and 10 to test the main hypothesis that veterans in the Combined condition would have a greater decline in depressive symptoms. The Combined intervention yielded a significant decline in depressive symptoms when compared with Usual Care. However, the there was no significant difference between the Combined and Illness Management Only groups. This is a pilot study with a small sample size relative to a standard randomized controlled trial in psychotherapy. This telephone-based intervention succeeded in reducing depressive symptoms in veterans with chronic illness. It adds to the building evidence base for providing phone-delivered mental health services. © 2013 Elsevier B.V. All rights reserved.
Type D personality is associated with social anxiety in the general population.
Kupper, Nina; Denollet, Johan
2014-06-01
Research on the emotional processes associated with Type D personality is important for its further conceptualization. We examined the associations of Type D personality with social and general anxiety symptoms in a large community sample. The aim of the current study was to disentangle the associations of Type D personality and its components with social anxiety and general anxiety in a large sample from the general population. A random sample of 2,475 adults from the general population filled out questionnaires to assess Type D personality (DS-14), social anxiety (SIAS(10), SPS(11), BFNE-II), and general anxiety (HADS-A, GAD-7). Type D individuals were characterized by increased levels of both social and general anxiety. The social inhibition (SI) component of Type D personality was most strongly associated with social interaction anxiety (r = .63), while negative affectivity (NA) was strongly associated with general anxiety (GAD-7: r = .70; HADS-A: r = .66). Within social anxiety, SI was more strongly associated with facets of social interaction anxiety than with social phobia. Multiple regression analysis showed that the synergistic interaction of NA and SI was a predictor of social anxiety (SIAS(10): β = .32, p < .0005; SPS(11): β = .27, p < .0005; BFNE-II: β = .11, p = .007) independent of demographics and the scores on the individual Type D components. This interaction was not a significant predictor of general anxiety. Logistic regression using the dichotomous Type D classification demonstrated a 9.1-fold (95%CI, 7.0-11.8) increased odds of a score in the highest quartile of social interaction anxiety and a 7.6-fold (95%CI, 5.8-9.8) increased odds of high social phobia. Odds ratios for clinically relevant levels of general anxiety were 8.3 (95%CI, 5.5-12.5) for GAD-7 and 6.5 (95%CI, 3.4-12.6) for HADS-A. In the general population, Type D individuals were characterized by both social and general anxiety. The SI component of Type D is strongly associated with social interaction anxiety and the synergistic interaction of NA and SI was associated with high social anxiety, above and beyond the main NA and SI effects.
Sample and population exponents of generalized Taylor's law.
Giometto, Andrea; Formentin, Marco; Rinaldo, Andrea; Cohen, Joel E; Maritan, Amos
2015-06-23
Taylor's law (TL) states that the variance V of a nonnegative random variable is a power function of its mean M; i.e., V = aM(b). TL has been verified extensively in ecology, where it applies to population abundance, physics, and other natural sciences. Its ubiquitous empirical verification suggests a context-independent mechanism. Sample exponents b measured empirically via the scaling of sample mean and variance typically cluster around the value b = 2. Some theoretical models of population growth, however, predict a broad range of values for the population exponent b pertaining to the mean and variance of population density, depending on details of the growth process. Is the widely reported sample exponent b ≃ 2 the result of ecological processes or could it be a statistical artifact? Here, we apply large deviations theory and finite-sample arguments to show exactly that in a broad class of growth models the sample exponent is b ≃ 2 regardless of the underlying population exponent. We derive a generalized TL in terms of sample and population exponents b(jk) for the scaling of the kth vs. the jth cumulants. The sample exponent b(jk) depends predictably on the number of samples and for finite samples we obtain b(jk) ≃ k = j asymptotically in time, a prediction that we verify in two empirical examples. Thus, the sample exponent b ≃ 2 may indeed be a statistical artifact and not dependent on population dynamics under conditions that we specify exactly. Given the broad class of models investigated, our results apply to many fields where TL is used although inadequately understood.
The efficacy of respondent-driven sampling for the health assessment of minority populations.
Badowski, Grazyna; Somera, Lilnabeth P; Simsiman, Brayan; Lee, Hye-Ryeon; Cassel, Kevin; Yamanaka, Alisha; Ren, JunHao
2017-10-01
Respondent driven sampling (RDS) is a relatively new network sampling technique typically employed for hard-to-reach populations. Like snowball sampling, initial respondents or "seeds" recruit additional respondents from their network of friends. Under certain assumptions, the method promises to produce a sample independent from the biases that may have been introduced by the non-random choice of "seeds." We conducted a survey on health communication in Guam's general population using the RDS method, the first survey that has utilized this methodology in Guam. It was conducted in hopes of identifying a cost-efficient non-probability sampling strategy that could generate reasonable population estimates for both minority and general populations. RDS data was collected in Guam in 2013 (n=511) and population estimates were compared with 2012 BRFSS data (n=2031) and the 2010 census data. The estimates were calculated using the unweighted RDS sample and the weighted sample using RDS inference methods and compared with known population characteristics. The sample size was reached in 23days, providing evidence that the RDS method is a viable, cost-effective data collection method, which can provide reasonable population estimates. However, the results also suggest that the RDS inference methods used to reduce bias, based on self-reported estimates of network sizes, may not always work. Caution is needed when interpreting RDS study findings. For a more diverse sample, data collection should not be conducted in just one location. Fewer questions about network estimates should be asked, and more careful consideration should be given to the kind of incentives offered to participants. Copyright © 2017. Published by Elsevier Ltd.
Towards representative energy data: the Machiguenga study.
Montgomery, E
1978-01-01
Representative energy data for a human population can be produced by combining randomly sampled time allocation observations with activity-specific energy expenditure measurements. Research to produce representative energy data for adults of a population of Machiguenga Indians has recently been conducted in lowland, southeastern Peru. Marked contrast was found between the sexes for average married adults in energy expended on an average day. Men spent about 3,200 kcals and women, about 1,925; ratio: 1.66 to 1. In general, men tended to work at somewhat more energetic activities and for longer periods than did women. In addition to sex-role-related task differences were contrasts in uses of technological items and in respective work settings. These representative behavior data permit direct estimates of population-level energy requirements for average days, seasons, or for 1 year.
Transposable element islands facilitate adaptation to novel environments in an invasive species
Schrader, Lukas; Kim, Jay W.; Ence, Daniel; Zimin, Aleksey; Klein, Antonia; Wyschetzki, Katharina; Weichselgartner, Tobias; Kemena, Carsten; Stökl, Johannes; Schultner, Eva; Wurm, Yannick; Smith, Christopher D.; Yandell, Mark; Heinze, Jürgen; Gadau, Jürgen; Oettler, Jan
2014-01-01
Adaptation requires genetic variation, but founder populations are generally genetically depleted. Here we sequence two populations of an inbred ant that diverge in phenotype to determine how variability is generated. Cardiocondyla obscurior has the smallest of the sequenced ant genomes and its structure suggests a fundamental role of transposable elements (TEs) in adaptive evolution. Accumulations of TEs (TE islands) comprising 7.18% of the genome evolve faster than other regions with regard to single-nucleotide variants, gene/exon duplications and deletions and gene homology. A non-random distribution of gene families, larvae/adult specific gene expression and signs of differential methylation in TE islands indicate intragenomic differences in regulation, evolutionary rates and coalescent effective population size. Our study reveals a tripartite interplay between TEs, life history and adaptation in an invasive species. PMID:25510865
Traffic-related air pollution and risk for leukaemia of an adult population.
Raaschou-Nielsen, Ole; Ketzel, Matthias; Harbo Poulsen, Aslak; Sørensen, Mette
2016-03-01
Air pollution causes lung cancer, but associations with other cancers have not been established. We investigated whether long-term exposure to traffic-related air pollution is associated with the risk of the general population for leukaemia. We identified 1,967 people in whom leukaemia was diagnosed in 1992-2010 from a nation-wide cancer registry and selected 3,381 control people at random, matched on sex and year of birth, from the entire Danish population. Residential addresses since 1971 were traced in a population registry, and outdoor concentrations of NOx and NO2 , as indicators of traffic-related air pollution, were calculated at each address in a dispersion model. We used conditional logistic regression to estimate the risk for leukaemia after adjustment for income, educational level, cohabitation status and co-morbidity. In linear analyses, we found odds ratios for acute myeloid leukaemia of 1.20 (95% confidence interval: 1.04-1.38) per 20 µg/m(3) increase in NOx and 1.31 (1.02-1.68) per 10 µg/m(3) increase in NO2 , calculated as time-weighted average exposure at all addresses since 1971. We found no association with chronic myeloid or lymphocytic leukaemia. This study indicates an association between long-term exposure to traffic-related air pollution and acute myeloid leukaemia in the general population, but not for other subtypes of leukaemia. © 2015 UICC.
Bakkar, May M; Shihadeh, Wisam A; Haddad, Mera F; Khader, Yousef S
2016-06-01
To describe the prevalence of dry eye disease (DED) symptoms and to identify associated risk factors in a general non-clinical population in Jordan. In this cross-sectional study, participants were selected randomly from the general non-clinical population in Jordan. Participants aged 18 years or over completed the Arabic version of Ocular Surface Disease Index (OSDI) questionnaire on dry eye symptoms. The OSDI questionnaire was completed by 1039 subjects (609 female and 430 male). The mean OSDI score for the study population was 27, with 59% of subjects showed OSDI score ≥20 (a cut off score for mild DED symptoms). Females showed significantly higher mean OSDI score than males in the older age group (p=0.01). The prevalence of all dryness symptoms was markedly reported in older age group >45 years and contact lens wearers (p<0.05). The most commonly reported DED symptom was sensitivity to light and intense symptoms were markedly reported during windy conditions. Vision-related quality of life was also affected in subjects with dryness symptoms. Working with computers and ATM was among those that highly affected. The results show that symptoms of dry eye were prevalent in this non-clinical population. Contact lenses wear and older age were found to be associated with dry eye symptoms. Copyright © 2015 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.
Jensen, Anne M; Ramasamy, Adaikalavan; Hall, Michael W
2012-08-01
General flexibility is a key component of health, well-being, and general physical conditioning. Reduced flexibility has both physical and mental/emotional etiologies and can lead to musculoskeletal injuries and athletic underperformance. Few studies have tested the effectiveness of a mind-body therapy on general flexibility. The aim of this study was to investigate if Neuro Emotional Technique® (NET), a mind-body technique shown to be effective in reducing stress, can also improve general flexibility. The sit-and-reach test (SR) score was used as a measure of general flexibility. Forty-five healthy participants were recruited from the general population and assessed for their initial SR score before being randomly allocated to receive (a) two 20-minute sessions of NET (experimental group); (b) two 20-minute sessions of stretching instruction (active control group); or (c) no intervention or instruction (passive control group). After intervention, the participants were reassessed in a similar manner by the same blind assessor. The participants also answered questions about demographics, usual water and caffeine consumption, and activity level, and they completed an anxiety/mood psychometric preintervention and postintervention. The mean (SD) change in the SR score was +3.1 cm (2.5) in the NET group, +1.2 cm (2.3) in the active control group and +1.0 cm (2.6) in the passive control group. Although all the 3 groups showed some improvement, the improvement in the NET group was statistically significant when compared with that of either the passive controls (p = 0.015) or the active controls (p = 0.021). This study suggests that NET could provide an effective treatment in improving general flexibility. A larger study is required to confirm these findings and also to assess longer term effectiveness of this therapy on general flexibility.
Punzo, Antonio; Ingrassia, Salvatore; Maruotti, Antonello
2018-04-22
A time-varying latent variable model is proposed to jointly analyze multivariate mixed-support longitudinal data. The proposal can be viewed as an extension of hidden Markov regression models with fixed covariates (HMRMFCs), which is the state of the art for modelling longitudinal data, with a special focus on the underlying clustering structure. HMRMFCs are inadequate for applications in which a clustering structure can be identified in the distribution of the covariates, as the clustering is independent from the covariates distribution. Here, hidden Markov regression models with random covariates are introduced by explicitly specifying state-specific distributions for the covariates, with the aim of improving the recovering of the clusters in the data with respect to a fixed covariates paradigm. The hidden Markov regression models with random covariates class is defined focusing on the exponential family, in a generalized linear model framework. Model identifiability conditions are sketched, an expectation-maximization algorithm is outlined for parameter estimation, and various implementation and operational issues are discussed. Properties of the estimators of the regression coefficients, as well as of the hidden path parameters, are evaluated through simulation experiments and compared with those of HMRMFCs. The method is applied to physical activity data. Copyright © 2018 John Wiley & Sons, Ltd.
Saad, Khaled; Eltayeb, Azza A; Mohamad, Ismail L; Al-Atram, Abdulrahman A; Elserogy, Yasser; Bjørklund, Geir; El-Houfey, Amira A; Nicholson, Bubba
2015-08-31
There is growing evidence for a gut-brain connection associated with autism spectrum disorders (ASDs). This suggests a potential benefit from introduced digestive enzymes for children with ASD. We performed a double-blind, randomized clinical trial on 101 children with ASD (82 boys and 19 girls) aged from 3 to 9 years. ASD patients were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders 4th edition, text revision (DSM-IV-TR) diagnostic criteria. Structured interviews of at least one hour each both with the parents and the child were performed. Later on, another two hours-session was conducted applying the Childhood Autism Rating Scale (CARS). ASD patients were randomized to receive digestive enzymes or placebo. The ASD group receiving digestive enzyme therapy for 3 months had significant improvement in emotional response, general impression autistic score, general behavior and gastrointestinal symptoms. Our study demonstrated the usefulness of digestive enzyme in our population of ASD patients. Digestive enzymes are inexpensive, readily available, have an excellent safety profile, and have mildly beneficial effects in ASD patients. Depending on the parameter measured in our study, we propose digestive enzymes for managing symptoms of ASD. Digestive enzyme therapy may be a possible option in treatment protocols for ASD in the future.
The "Pathological Gambling and Epidemiology" (PAGE) study program: design and fieldwork.
Meyer, Christian; Bischof, Anja; Westram, Anja; Jeske, Christine; de Brito, Susanna; Glorius, Sonja; Schön, Daniela; Porz, Sarah; Gürtler, Diana; Kastirke, Nadin; Hayer, Tobias; Jacobi, Frank; Lucht, Michael; Premper, Volker; Gilberg, Reiner; Hess, Doris; Bischof, Gallus; John, Ulrich; Rumpf, Hans-Jürgen
2015-03-01
The German federal states initiated the "Pathological Gambling and Epidemiology" (PAGE) program to evaluate the public health relevance of pathological gambling. The aim of PAGE was to estimate the prevalence of pathological gambling and cover the heterogenic presentation in the population with respect to comorbid substance use and mental disorders, risk and protective factors, course aspects, treatment utilization, triggering and maintenance factors of remission, and biological markers. This paper describes the methodological details of the study and reports basic prevalence data. Two sampling frames (landline and mobile telephone numbers) were used to generate a random sample from the general population consisting of 15,023 individuals (ages 14 to 64) completing a telephone interview. Additionally, high-risk populations have been approached in gambling locations, via media announcements, outpatient addiction services, debt counselors, probation assistants, self-help groups and specialized inpatient treatment facilities. The assessment included two steps: (1) a diagnostic interview comprising the gambling section of the Composite International Diagnostic Interview (CIDI) for case finding; (2) an in-depth clinical interview with participants reporting gambling problems. The in-depth clinical interview was completed by 594 participants, who were recruited from the general or high-risk populations. The program provides a rich epidemiological database which is available as a scientific use file. Copyright © 2015 John Wiley & Sons, Ltd.
[Prevalence of irritable bowel syndrome in Veracruz City, Mexico: a community-based survey].
Valerio-Ureña, J; Vásquez-Fernández, F; Jiménez-Pineda, A; Cortázar-Benítez, L F; Azamar-Jácome, A A; Duarte-Velázquez, M E; Torres-Medina, V
2010-01-01
Irritable bowel syndrome (IBS) is recognized as the most frequent functional digestive disorder around the world. In Latin America and Mexico there are few studies in order to demonstrate its real prevalence in general population. To determine the prevalence of IBS in general population from Veracruz City Mexico, using the Rome II criteria. Using basic information given by bureau for planning urban services from Veracruz country, a 10% random population sample was obtained. Subjects between 16-80 years old were interviewed using a questionnaire based on Rome II criteria and a visual analogous scale in order to estimate the negative effect of IBS symptoms on daily activities. We interviewed 459 subjects with a median age of 31.2 +/- 13.6 years old detecting 78 subjects (16.9%) with IBS symptoms: 25 males and 53 females (gender prevalence of 11.3% and 22.1%, respectively). 28.2% of them had IBS with diarrhea, 50% had IBS with constipation and 21.8% alternating bowel movements, diarrhea and constipation. Negative effect of IBS symptoms on daily activities was significant. The prevalence of IBS in open population was 16.9% according to Rome II criteria, being higher in those older than 35 years old. Constipation was the predominant pattern. Further studies should evaluate associated factors of these findings.
Seroepidemiology of HBV infection in South-East of iran; a population based study.
Salehi, M; Alavian, S M; Tabatabaei, S V; Izadi, Sh; Sanei Moghaddam, E; Amini Kafi-Abad, S; Gharehbaghian, A; Khosravi, S; Abolghasemi, H
2012-05-01
Hepatitis B virus (HBV) infection is a major risk factor of cirrhosis and hepatocellular carcinoma affecting billions of people globally. Since information on its prevalence in general population is mandatory for formulating effective policies, this population based serological survey was conducted in Sistan and Baluchistan, where no previous epidemiological data were available. Using random cluster sampling 3989 healthy subjects were selected from 9 districts of Sistan and Baluchistan Province in southeastern Iran. The subjects' age ranged from 6 to 65 years old. Serum samples were tested for HBcAb, HBsAg. Screening tests were carried out by the third generation of ELISA. Various risk factors were recorded and multivariate analysis was performed. The prevalence of HBsAg and HBcAb in Sistan and Baluchistan was 3.38% (95% CI 2.85; 3.98) and 23.58% (95% CI 22.29; 24.93) respectively. We found 8 cases of positive anti-HDV antibody. Predictors of HBsAg or HBcAb in multivariate analysis were age, marital status and addiction. The rate of HBV infection in Sistan and Baluchistan was higher than other parts of Iran. Approximately 25% of general population in this province had previous exposure to HBV and 3% were HBsAg carriers. Intrafamilial and addiction were major routes of HBV transmission in this province.
Campbell, Marci Kramish; Carr, Carol; Devellis, Brenda; Switzer, Boyd; Biddle, Andrea; Amamoo, M Ahinee; Walsh, Joan; Zhou, Bingqing; Sandler, Robert
2009-10-01
Healthful dietary patterns, including eating fruits and vegetables (F&V) and avoiding obesity, may decrease the risk of cancer and other chronic diseases. In addition to promoting health for the general population, a cancer diagnosis may provide a "teachable moment," facilitating the adoption of more healthful eating habits and leading to lower risk of chronic disease and better overall health. This study was designed to test the effectiveness of two health communication interventions in increasing F&V consumption and physical activity in a sample of older adults (average age of 66 years), including both colorectal cancer (CRC) survivors and noncolorectal cancer-affected (N-CRC) individuals. CRC survivors and N-CRC individuals were recruited from a population-based case-control study and randomly assigned to four conditions using a 2 x 2 design. We tested two different methods of communicating and promoting health behavior change alone or in combination: tailored print communication (TPC) and brief telephone-based motivational interviewing (TMI). A significant increase in F&V consumption was found for the combined intervention group in the entire sample (p < 0.05). When stratified by cancer survivor status, the effect was concentrated in the N-CRC subset (p < 0.01) versus CRC survivors. The combined intervention was also found to be most cost-effective for the N-CRC group, with TPC more cost-effective than TMI. For physical activity, none of the interventions produced statistically significant improvements. This study indicates that combining tailoring and motivational interviewing may be an effective and cost-effective method for promoting dietary behavior change among older healthy adults. More research is needed to identify the optimal dose and timing for intervention strategies to promote dietary and physical activity change among both CRC survivors and the general population.
Oizumi, Ryo
2014-01-01
Life history of organisms is exposed to uncertainty generated by internal and external stochasticities. Internal stochasticity is generated by the randomness in each individual life history, such as randomness in food intake, genetic character and size growth rate, whereas external stochasticity is due to the environment. For instance, it is known that the external stochasticity tends to affect population growth rate negatively. It has been shown in a recent theoretical study using path-integral formulation in structured linear demographic models that internal stochasticity can affect population growth rate positively or negatively. However, internal stochasticity has not been the main subject of researches. Taking account of effect of internal stochasticity on the population growth rate, the fittest organism has the optimal control of life history affected by the stochasticity in the habitat. The study of this control is known as the optimal life schedule problems. In order to analyze the optimal control under internal stochasticity, we need to make use of "Stochastic Control Theory" in the optimal life schedule problem. There is, however, no such kind of theory unifying optimal life history and internal stochasticity. This study focuses on an extension of optimal life schedule problems to unify control theory of internal stochasticity into linear demographic models. First, we show the relationship between the general age-states linear demographic models and the stochastic control theory via several mathematical formulations, such as path-integral, integral equation, and transition matrix. Secondly, we apply our theory to a two-resource utilization model for two different breeding systems: semelparity and iteroparity. Finally, we show that the diversity of resources is important for species in a case. Our study shows that this unification theory can address risk hedges of life history in general age-states linear demographic models.
Unification Theory of Optimal Life Histories and Linear Demographic Models in Internal Stochasticity
Oizumi, Ryo
2014-01-01
Life history of organisms is exposed to uncertainty generated by internal and external stochasticities. Internal stochasticity is generated by the randomness in each individual life history, such as randomness in food intake, genetic character and size growth rate, whereas external stochasticity is due to the environment. For instance, it is known that the external stochasticity tends to affect population growth rate negatively. It has been shown in a recent theoretical study using path-integral formulation in structured linear demographic models that internal stochasticity can affect population growth rate positively or negatively. However, internal stochasticity has not been the main subject of researches. Taking account of effect of internal stochasticity on the population growth rate, the fittest organism has the optimal control of life history affected by the stochasticity in the habitat. The study of this control is known as the optimal life schedule problems. In order to analyze the optimal control under internal stochasticity, we need to make use of “Stochastic Control Theory” in the optimal life schedule problem. There is, however, no such kind of theory unifying optimal life history and internal stochasticity. This study focuses on an extension of optimal life schedule problems to unify control theory of internal stochasticity into linear demographic models. First, we show the relationship between the general age-states linear demographic models and the stochastic control theory via several mathematical formulations, such as path–integral, integral equation, and transition matrix. Secondly, we apply our theory to a two-resource utilization model for two different breeding systems: semelparity and iteroparity. Finally, we show that the diversity of resources is important for species in a case. Our study shows that this unification theory can address risk hedges of life history in general age-states linear demographic models. PMID:24945258
Domestic and sexual violence against patients with severe mental illness.
Khalifeh, H; Moran, P; Borschmann, R; Dean, K; Hart, C; Hogg, J; Osborn, D; Johnson, S; Howard, L M
2015-03-01
Domestic and sexual violence are significant public health problems but little is known about the extent to which men and women with severe mental illness (SMI) are at risk compared with the general population. We aimed to compare the prevalence and impact of violence against SMI patients and the general population. Three hundred and three randomly recruited psychiatric patients, in contact with community services for ⩾ 1 year, were interviewed using the British Crime Survey domestic/sexual violence questionnaire. Prevalence and correlates of violence in this sample were compared with those from 22 606 general population controls participating in the contemporaneous 2011/12 national crime survey. Past-year domestic violence was reported by 27% v. 9% of SMI and control women, respectively [odds ratio (OR) adjusted for socio-demographics, aOR 2.7, 95% confidence interval (CI) 1.7-4.0], and by 13% v. 5% of SMI and control men, respectively (aOR 1.6, 95% CI 1.0-2.8). Past-year sexual violence was reported by 10% v. 2.0% of SMI and control women respectively (aOR 2.9, 95% CI 1.4-5.8). Family (non-partner) violence comprised a greater proportion of overall domestic violence among SMI than control victims (63% v. 35%, p < 0.01). Adulthood serious sexual assault led to attempted suicide more often among SMI than control female victims (53% v. 3.4%, p < 0.001). Compared to the general population, patients with SMI are at substantially increased risk of domestic and sexual violence, with a relative excess of family violence and adverse health impact following victimization. Psychiatric services, and public health and criminal justice policies, need to address domestic and sexual violence in this at-risk group.
Moćko, Paweł; Kawalec, Paweł; Smela-Lipińska, Beata; Pilc, Andrzej
2016-10-01
The aim of this systematic review (SR) and meta-analysis was to assess the efficacy and safety of vedolizumab in the treatment of Crohn's disease (CD). A systematic literature search was conducted in Medline/PubMed, Embase and Cochrane Library until 25 January, 2015. Included studies were critically appraised according to the PRISMA protocol. Assessment in specified subgroups of CD patients and meta-analysis with Revman software were performed. Two randomized controlled trial (RCTs) were included in a meta-analysis for the induction phase of therapy: GEMINI II and GEMINI III. The clinical response was significantly higher for patients who received vedolizumab compared to placebo in the general population (risk benefit (RB) = 1.48; p = 0.0006) and in both analyzed subgroups: patients with previous failure of anti-TNFs treatment (RB = 1.51; p = 0.006) and patients naive to earlier anti-TNFs (RB = 1.41; p = 0.001). The clinical remission in the general population and subpopulation of TNF-antagonist naive patients was significantly higher for patients who received vedolizumab compared to placebo (RB = 1.77; p = 0.003; RB = 2.29; p = 0.0004; respectively). Meta-analysis for adverse events, serious adverse events (SAEs) and serious infections, revealed that vedolizumab was as safe as placebo in the induction phase of therapy. The clinical response was significantly higher for patients who received vedolizumab in the general population and in both analyzed subgroups of patients. The clinical remission in the general population and subpopulation of TNF-antagonist naive patients was significantly higher for vedolizumab, but no significant differences were revealed in the subgroup of patients with previous TNF antagonist failure.
Keller, Carmen; Siegrist, Michael
2015-09-01
In an obesogenic environment, people have to adopt effective weight management strategies to successfully gain or maintain normal body weight. Little is known about the strategies used by the general population in daily life. Due to the lack of a comprehensive measurement instrument to assess conceptually different strategies with various scales, we developed the weight management strategies inventory (WMSI). In study 1, we collected 19 weight management strategies from research on self-regulation of food intake and successful weight loss and maintenance, as well as from expert interviews. We classified them under the five main categories of health self-regulation strategies - goal setting and monitoring, prospection and planning, automating behavior, construal, and inhibition. We formulated 93 items. In study 2, we developed the WMSI in a random sample from the general population (N = 658), using reliability and exploratory factor analysis. This resulted in 19 factors with 63 items, representing the 19 strategies. In study 3, we tested the 19-factor structure in a quota (age, gender) sample from the general population (N = 616), using confirmatory factor analysis. A good model fit (CFI = .918; RMSEA = .043) was revealed. Reliabilities and construct validity were high. Positive correlations of most strategies with dieting success and negative correlations of some strategies with body mass index were found among dieters (N = 292). Study 4 (N = 162) revealed a good test-retest reliability. The WMSI assesses theoretically derived, evidence-based, and conceptually different weight management strategies with different scales that have good psychometric characteristics. The scales can also be used for pre- and post measures in intervention studies. The scales provide insights into the general population's weight management strategies and facilitate tailoring and evaluating health communication. Copyright © 2015 Elsevier Ltd. All rights reserved.
Bjornsdottir, Erla; Keenan, Brendan T; Eysteinsdottir, Bjorg; Arnardottir, Erna Sif; Janson, Christer; Gislason, Thorarinn; Sigurdsson, Jon Fridrik; Kuna, Samuel T; Pack, Allan I; Benediktsdottir, Bryndis
2015-06-01
Obstructive sleep apnea leads to recurrent arousals from sleep, oxygen desaturations, daytime sleepiness and fatigue. This can have an adverse impact on quality of life. The aims of this study were to compare: (i) quality of life between the general population and untreated patients with obstructive sleep apnea; and (ii) changes of quality of life among patients with obstructive sleep apnea after 2 years of positive airway pressure treatment between adherent patients and non-users. Propensity score methodologies were used in order to minimize selection bias and strengthen causal inferences. The enrolled obstructive sleep apnea subjects (n = 822) were newly diagnosed with moderate to severe obstructive sleep apnea who were starting positive airway pressure treatment, and the general population subjects (n = 742) were randomly selected Icelanders. The Short Form 12 was used to measure quality of life. Untreated patients with obstructive sleep apnea had a worse quality of life when compared with the general population. This effect remained significant after using propensity scores to select samples, balanced with regard to age, body mass index, gender, smoking, diabetes, hypertension and cardiovascular disease. We did not find significant overall differences between full and non-users of positive airway pressure in improvement of quality of life from baseline to follow-up. However, there was a trend towards more improvement in physical quality of life for positive airway pressure-adherent patients, and the most obese subjects improved their physical quality of life more. The results suggest that co-morbidities of obstructive sleep apnea, such as obesity, insomnia and daytime sleepiness, have a great effect on life qualities and need to be taken into account and addressed with additional interventions. © 2014 European Sleep Research Society.
Aftab, Awais; Bhat, Chetan; Gunzler, Douglas; Cassidy, Kristin; Thomas, Charles; McCormick, Richard; Dawson, Neal V; Sajatovic, Martha
2018-05-01
Objective Serious mental illness and type II diabetes mellitus have a high comorbidity, and both have a higher prevalence of anxiety disorders compared to the general population. Targeted Training in Illness Management is a group-based self-management training approach which targets serious mental illness and type II diabetes mellitus concurrently. This analysis examines data from a randomized controlled trial of Targeted Training in Illness Management intervention to examine the impact of comorbid anxiety on baseline psychiatric symptomatology and diabetic control, and on longitudinal treatment outcomes. Methods We conducted secondary analyses on data from a prospective, 60-week, randomized controlled trial testing Targeted Training in Illness Management versus treatment as usual in 200 individuals with serious mental illness and diabetes. Primary outcomes included measures related to serious mental illness symptoms, functional status, general health status, and diabetes control. Measures were compared between those participants with anxiety disorders versus those without anxiety at baseline as well as over time using linear mixed effects analyses. Results Forty seven percent of the participants had one or more anxiety disorders. At baseline, those with an anxiety diagnosis had higher illness severity, depressive, and other psychiatric symptomatology and disability. Diabetic control (HbA1c) was not significantly different at baseline. In the longitudinal analyses, no significant mean slope differences over time (group-by-time interaction effect) between those with anxiety diagnoses and those without in treatment as usual group were found for primary outcomes. Within the Targeted Training in Illness Management arm, those with anxiety disorders had significantly greater improvement in mental health functioning. Those with anxiety comorbidity in the Targeted Training in Illness Management group demonstrated significantly lower HbA1c levels compared to no anxiety comorbidity and also demonstrated a greater improvement in HbA1c over the first 30 weeks compared to those without anxiety comorbidity. Conclusion Comorbid anxiety in serious mental illness and type II diabetes mellitus population is associated with increased psychiatric symptomatology and greater disability. Individuals from this population appear to experience greater improvement in functioning from baseline with the Targeted Training in Illness Management intervention. Anxiety comorbidity in the serious mental illness and type II diabetes mellitus population does not appear to have a negative impact on diabetic control. These complex relationships need further study. Clinical Trials Registration ClinicalTrials.gov: Improving outcomes for individuals with serious mental illness and diabetes (NCT01410357).
Guillén-Riquelme, Alejandro; Buela-Casal, Gualberto
2014-01-01
Since its creation the STAI has been cited in more than 14,000 documents, with more than 60 adaptations in different countries. In some adaptations this instrument has no clinical scores. The aim of this work is to determine if the State-Trait Anxiety Inventory (STAI) has higher scores in patients diagnosed with anxiety than in general population. In addition, we want to examine if the internal consistency is adequate in anxious patient samples. We performed a literature search in Tripdatabase, Cochrane, Web of Knowledge, Scopus, PyscINFO and Scholar Google, for documents published between 2008 y 2012. We selected 131 scientific articles to compare between patients diagnosed with anxiety and general population, and 25 for the generalization of reliability. For the analysis we used Cohen's d for means comparisons (random-effects method) and Cronbach's alpha for the reliability generalization (fixed-effects method). In the groups comparision the differences in state anxiety (d=1.39; CI95%: 1.22-1.56) and in the trait anxiety (d=1.74; CI95%:1.56-1.91) were significants. The reliability for patients of some anxiety disorder was between 0.87 and 0.93. So it seems that the STAI is sensitive to the level of anxiety of the individual and reliable for patients with diagnosis of panic attack, specific phobia, social phobia, generalized social phobia, generalized anxiety disorder, post-traumatic stress disorder, obsessive compulsive disorder or acute Stress disorder.
Artigao-Rodenas, Luis M; Carbayo-Herencia, Julio A; Divisón-Garrote, Juan A; Gil-Guillén, Vicente F; Massó-Orozco, Javier; Simarro-Rueda, Marta; Molina-Escribano, Francisca; Sanchis, Carlos; Carrión-Valero, Lucinio; López de Coca, Enrique; Caldevilla, David; López-Abril, Juan; Carratalá-Munuera, Concepción; Lopez-Pineda, Adriana
2013-01-01
The question about what risk function should be used in primary prevention remains unanswered. The Framingham Study proposed a new algorithm based on three key ideas: use of the four risk factors with the most weight (cholesterol, blood pressure, diabetes and smoking), prediction of overall cardiovascular diseases and incorporating the concept of vascular age. The objective of this study was to apply this new function in a cohort of the general non Anglo-Saxon population, with a 10-year follow-up to determine its validity. The cohort was studied in 1992-94 and again in 2004-06. The sample comprised 959 randomly-selected persons, aged 30-74 years, who were representative of the population of Albacete, Spain. At the first examination cycle, needed data for the new function were collected and at the second examination, data on all events were recorded during the follow-up period. Discrimination was studied with ROC curves. Comparisons of prediction models and reality in tertiles (Hosmer-Lemeshow) were performed, and the individual survival functions were calculated. The mean risks for women and men, respectively, were 11.3% and 19.7% and the areas under the ROC curve were 0.789 (95%CI, 0.716-0.863) and 0.780 (95%CI, 0.713-0.847) (P<0.001, both). Cardiovascular disease events occurred in the top risk tertiles. Of note were the negative predictive values in both sexes, and a good specificity in women (85.6%) and sensitivity in men (79.1%) when their risk for cardiovascular disease was high. This model overestimates the risk in older women and in middle-aged men. The cumulative probability of individual survival by tertiles was significant in both sexes (P<0.001). The results support the proposal for "reclassification" of Framingham. This study, with a few exceptions, passed the test of discrimination and calibration in a random sample of the general population from southern Europe.
Kulason, Kay; Nouchi, Rui; Hoshikawa, Yasushi; Noda, Masafumi; Okada, Yoshinori; Kawashima, Ryuta
2018-01-01
Background: There has been little research conducted regarding cognitive treatments for the elderly postsurgical population. Patients aged ≥60 years have an increased risk of postoperative cognitive decline, a condition in which cognitive functions are negatively affected. This cognitive decline can lead to a decline in quality of life. In order to maintain a high quality of life, the elderly postsurgical population may benefit from treatment to maintain and/or improve their cognitive functions. This pilot study investigates the effect of simple calculation and reading aloud (SCRA) cognitive training in elderly Japanese postsurgical patients. Methods: Elderly patients undergoing non-cardiovascular thoracic surgery under general anesthesia were recruited ( n = 12). Subjects were randomly divided into two groups-one that receives 12 weeks of SCRA intervention, and a waitlisted control group. Before and after the intervention, we measured cognitive function [Mini-Mental Status Exam-Japanese (MMSE-J), Frontal Assessment Battery (FAB), computerized Cogstate Brief Battery (CBB)] and emotional state [General Health Questionnaire-12 (GHQ-12), Geriatric Depression Scale (GDS), Quality of Life Scale-5 (QOL-5)]. Results: Group difference analyses using ANCOVA with permutation test showed that the intervention SCRA group had a significant improvement in FAB motor programming sub-score, GDS, and QOL-5 compared to the control group. Within-group analyses using Wilcoxon signed-rank test to compare baseline and follow-up showed that the SCRA intervention group total FAB scores, FAB motor programming sub-scores, and QOL-5 scores were significantly improved. Discussion: This pilot study showed that there are important implications for the beneficial effects of SCRA intervention on cognitive function and emotional state in the postoperative elderly population; however, further investigations are necessary to reach any conclusions. Trial registration: This study was registered with the University Hospital Medical Information Network (UMIN) Clinical Trial Registry (UMIN000019832).
Kulason, Kay; Nouchi, Rui; Hoshikawa, Yasushi; Noda, Masafumi; Okada, Yoshinori; Kawashima, Ryuta
2018-01-01
Background: There has been little research conducted regarding cognitive treatments for the elderly postsurgical population. Patients aged ≥60 years have an increased risk of postoperative cognitive decline, a condition in which cognitive functions are negatively affected. This cognitive decline can lead to a decline in quality of life. In order to maintain a high quality of life, the elderly postsurgical population may benefit from treatment to maintain and/or improve their cognitive functions. This pilot study investigates the effect of simple calculation and reading aloud (SCRA) cognitive training in elderly Japanese postsurgical patients. Methods: Elderly patients undergoing non-cardiovascular thoracic surgery under general anesthesia were recruited (n = 12). Subjects were randomly divided into two groups—one that receives 12 weeks of SCRA intervention, and a waitlisted control group. Before and after the intervention, we measured cognitive function [Mini-Mental Status Exam-Japanese (MMSE-J), Frontal Assessment Battery (FAB), computerized Cogstate Brief Battery (CBB)] and emotional state [General Health Questionnaire-12 (GHQ-12), Geriatric Depression Scale (GDS), Quality of Life Scale-5 (QOL-5)]. Results: Group difference analyses using ANCOVA with permutation test showed that the intervention SCRA group had a significant improvement in FAB motor programming sub-score, GDS, and QOL-5 compared to the control group. Within-group analyses using Wilcoxon signed-rank test to compare baseline and follow-up showed that the SCRA intervention group total FAB scores, FAB motor programming sub-scores, and QOL-5 scores were significantly improved. Discussion: This pilot study showed that there are important implications for the beneficial effects of SCRA intervention on cognitive function and emotional state in the postoperative elderly population; however, further investigations are necessary to reach any conclusions. Trial registration: This study was registered with the University Hospital Medical Information Network (UMIN) Clinical Trial Registry (UMIN000019832). PMID:29643802
F.Kaminski, Michal; Bretthauer, Michael; Zauber, Ann G.; Kuipers, Ernst J.; Adami, Hans-Olov; van Ballegooijen, Marjolein; Regula, Jaroslaw; van Leerdam, Monique; Stefansson, Tryggvi; Påhlman, Lars; Dekker, Evelien; Hernán, Miguel A.; Garborg, Kjetil; Hoff, Geir
2017-01-01
Background While colonoscopy screening is widely used in several European countries and the United States, no randomised trials exist to quantify its benefits. The Nordic-European Initiative on Colorectal Cancer (NordICC) is a multinational, randomized controlled trial aiming at investigating the effect of colonoscopy screening on CRC incidence and mortality. This paper describes the rationale and design of the NordICC trial. Material and methods Men and women age 55 to 64 years are drawn from the population registries in the participating countries and randomly assigned to either once-only colonoscopy screening with removal of all detected lesions, or no screening (standard of care in the trial regions). All individuals are followed for 15 years after inclusion using dedicated national registries. Results The primary endpoints of the trial are cumulative CRC-specific death and CRC incidence during 15 years of follow up. We hypothesize a 50% CRC mortality-reducing efficacy of the colonoscopy intervention and predict 50% compliance, yielding a 25% mortality reduction among those invited to screening. For 90% power and a two-sided alpha level of 0.05, using a 2:1 randomisation, 45,600 individuals will be randomised to control, and 22,800 individuals to the colonoscopy group. Interim analyses of the effect of colonoscopy on CRC incidence and mortality will be performed at 10 years follow-up. Conclusions The aim of the NordICC trial is to quantify the effectiveness of population-based colonoscopy screening. This will allow development of evidence-based guidelines for CRC screening in the general population. PMID:22723185
Farsi, Marco; Bernini, Marco; Bencini, Lapo; Miranda, Egidio; Manetti, Roberto; de Manzoni, Giovanni; Verlato, Giuseppe; Marrelli, Daniele; Pedrazzani, Corrado; Roviello, Francesco; Marchet, Alberto; Cristadoro, Luigi; Gerard, Leonardo; Moretti, Renato
2009-05-15
The incidence of gallstones and gallbladder sludge is known to be higher in patients after gastrectomy than in general population. This higher incidence is probably related to surgical dissection of the vagus nerve branches and the anatomical gastrointestinal reconstruction. Therefore, some surgeons perform routine concomitant cholecystectomy during standard surgery for gastric malignancies. However, not all the patients who are diagnosed to have cholelithiasis after gastric cancer surgery will develop symptoms or require additional surgical treatments and a standard laparoscopic cholecystectomy is feasible even in those patients who underwent previous gastric surgery. At the present, no randomized study has been published and the decision of gallbladder management is left to each surgeon preference. The study is a randomized controlled investigation. The study will be performed in the General and Oncologic Surgery, Department of Oncology-Azienda Ospedaliero-Universitaria Careggi-Florence-Italy, a large teaching institution, with the participation of all surgeons who accept to be involved in, together with other Italian Surgical Centers, on behalf of the GIRCG (Italian Research Group for Gastric Cancer).The patients will be randomized into two groups: in the first group the patient will be submitted to prophylactic cholecystectomy during standard surgery for curable gastric cancer (subtotal or total gastrectomy), while in the second group he/she will be submitted to standard gastric surgery only. ClinicalTrials.gov ID. NCT00757640.
From samples to populations in retinex models
NASA Astrophysics Data System (ADS)
Gianini, Gabriele
2017-05-01
Some spatial color algorithms, such as Brownian Milano retinex (MI-retinex) and random spray retinex (RSR), are based on sampling. In Brownian MI-retinex, memoryless random walks (MRWs) explore the neighborhood of a pixel and are then used to compute its output. Considering the relative redundancy and inefficiency of MRW exploration, the algorithm RSR replaced the walks by samples of points (the sprays). Recent works point to the fact that a mapping from the sampling formulation to the probabilistic formulation of the corresponding sampling process can offer useful insights into the models, at the same time featuring intrinsically noise-free outputs. The paper continues the development of this concept and shows that the population-based versions of RSR and Brownian MI-retinex can be used to obtain analytical expressions for the outputs of some test images. The comparison of the two analytic expressions from RSR and from Brownian MI-retinex demonstrates not only that the two outputs are, in general, different but also that they depend in a qualitatively different way upon the features of the image.
Etzioni, Ruth; Gulati, Roman
2013-04-01
In our article about limitations of basing screening policy on screening trials, we offered several examples of ways in which modeling, using data from large screening trials and population trends, provided insights that differed somewhat from those based only on empirical trial results. In this editorial, we take a step back and consider the general question of whether randomized screening trials provide the strongest evidence for clinical guidelines concerning population screening programs. We argue that randomized trials provide a process that is designed to protect against certain biases but that this process does not guarantee that inferences based on empirical results from screening trials will be unbiased. Appropriate quantitative methods are key to obtaining unbiased inferences from screening trials. We highlight several studies in the statistical literature demonstrating that conventional survival analyses of screening trials can be misleading and list a number of key questions concerning screening harms and benefits that cannot be answered without modeling. Although we acknowledge the centrality of screening trials in the policy process, we maintain that modeling constitutes a powerful tool for screening trial interpretation and screening policy development.
George, Christine Marie; Monira, Shirajum; Sack, David A; Rashid, Mahamud-ur; Saif-Ur-Rahman, K M; Mahmud, Toslim; Rahman, Zillur; Mustafiz, Munshi; Bhuyian, Sazzadul Islam; Winch, Peter J; Leontsini, Elli; Perin, Jamie; Begum, Farzana; Zohura, Fatema; Biswas, Shwapon; Parvin, Tahmina; Zhang, Xiaotong; Jung, Danielle; Sack, R Bradley; Alam, Munirul
2016-02-01
The risk for cholera infection is >100 times higher for household contacts of cholera patients during the week after the index patient seeks hospital care than it is for the general population. To initiate a standard of care for this high-risk population, we developed Cholera-Hospital-Based-Intervention-for-7-Days (CHoBI7), which promotes hand washing with soap and treatment of water. To test CHoBI7, we conducted a randomized controlled trial among 219 intervention household contacts of 82 cholera patients and 220 control contacts of 83 cholera patients in Dhaka, Bangladesh, during 2013-2014. Intervention contacts had significantly fewer symptomatic Vibrio cholerae infections than did control contacts and 47% fewer overall V. cholerae infections. Intervention households had no stored drinking water with V. cholerae and 14 times higher odds of hand washing with soap at key events during structured observation on surveillance days 5, 6, or 7. CHoBI7 presents a promising approach for controlling cholera among highly susceptible household contacts of cholera patients.
Use of MP3 players to increase asthma knowledge in inner-city African-American adolescents.
Mosnaim, Giselle S; Cohen, Marc S; Rhoads, Christopher H; Rittner, Sarah Stuart; Powell, Lynda H
2008-01-01
Low-income African-American adolescents suffer a disproportionate burden of asthma morbidity. To evaluate the ability of our intervention, the Adolescents' Disease Empowerment and Persistency Technology (ADEPT) for asthma, to increase asthma knowledge in our target population. This was a 14-week (2-week run-in and 12-week treatment) randomized, double-blind, placebo-controlled pilot study in which 28 inner-city African-American adolescents with asthma, between 10 and 18 years of age, were randomized to receive (1) celebrity asthma messages (experimental group), or (2) general health messages (control group) between music tracks on an MP3 player. The asthma messages were recorded by famous athletes, musicians, and other celebrities popular among this group of teenagers. Asthma knowledge, assessed by the ZAP Asthma Knowledge instrament, was collected pre- and post-intervention. Mean improvement in ZAP score was significantly higher in the experimental group (8.1%, SD 7.2%) than the control group (0.4%, SD 7.2%) (p = 0.05). These findings suggest that this may be an innovative and promising new approach to improving asthma outcomes in this difficult-to-reach population.
Recruitment for an efficacy study in chemoprevention--the Concerned Smoker Study.
Arnold, A; Johnstone, B; Stoskopf, B; Skingley, P; Browman, G; Levine, M; Hryniuk, W
1989-09-01
Efficacy studies are important for the development of long-term cancer prevention strategies. Recruitment aims for a highly motivated group of participants. The Concerned Smoker Study is aimed at smokers with at least a 15 pack-year history and bronchial atypia on sputum sampling Recruitment has been primarily through use of the media. During the first year of randomization 905 potential participants expressed interest. Of these, 80 were eventually randomized. With over 60 participants having completed the study only one has defaulted and compliance with the study protocol has been high. Participants became aware of the study through the following sources: daily newspaper 36.6%, weekly newspaper 16.2%, television 14.9%, radio 13.8%, community television 1.3%, other sources 13.3%. Over 90% of potential participants who initially express interest in such a chemoprevention project may not ultimately be suitable. The population chosen for such studies may not be very representative of the more general population; however, a high degree of compliance can be obtained which will provide valuable information on treatment efficacy.
Social cycling and conditional responses in the Rock-Paper-Scissors game
Wang, Zhijian; Xu, Bin; Zhou, Hai-Jun
2014-01-01
How humans make decisions in non-cooperative strategic interactions is a big question. For the fundamental Rock-Paper-Scissors (RPS) model game system, classic Nash equilibrium (NE) theory predicts that players randomize completely their action choices to avoid being exploited, while evolutionary game theory of bounded rationality in general predicts persistent cyclic motions, especially in finite populations. However as empirical studies have been relatively sparse, it is still a controversial issue as to which theoretical framework is more appropriate to describe decision-making of human subjects. Here we observe population-level persistent cyclic motions in a laboratory experiment of the discrete-time iterated RPS game under the traditional random pairwise-matching protocol. This collective behavior contradicts with the NE theory but is quantitatively explained, without any adjustable parameter, by a microscopic model of win-lose-tie conditional response. Theoretical calculations suggest that if all players adopt the same optimized conditional response strategy, their accumulated payoff will be much higher than the reference value of the NE mixed strategy. Our work demonstrates the feasibility of understanding human competition behaviors from the angle of non-equilibrium statistical physics. PMID:25060115
Population Fluctuation Promotes Cooperation in Networks
Miller, Steve; Knowles, Joshua
2015-01-01
We consider the problem of explaining the emergence and evolution of cooperation in dynamic network-structured populations. Building on seminal work by Poncela et al., which shows how cooperation (in one-shot prisoner’s dilemma) is supported in growing populations by an evolutionary preferential attachment (EPA) model, we investigate the effect of fluctuations in the population size. We find that a fluctuating model – based on repeated population growth and truncation – is more robust than Poncela et al.’s in that cooperation flourishes for a wider variety of initial conditions. In terms of both the temptation to defect, and the types of strategies present in the founder network, the fluctuating population is found to lead more securely to cooperation. Further, we find that this model will also support the emergence of cooperation from pre-existing non-cooperative random networks. This model, like Poncela et al.’s, does not require agents to have memory, recognition of other agents, or other cognitive abilities, and so may suggest a more general explanation of the emergence of cooperation in early evolutionary transitions, than mechanisms such as kin selection, direct and indirect reciprocity. PMID:26061705
Beliefs about gambling problems and recovery: results from a general population telephone survey.
Cunningham, John A; Cordingley, Joanne; Hodgins, David C; Toneatto, Tony
2011-12-01
Respondents were asked their beliefs about gambling abuse as part of a general population telephone survey. The random digit dialing survey consisted of 8,467 interviews of adults, 18 years and older, from Ontario, Canada (45% male; mean age = 46.2). The predominant conception of gambling abuse was that of an addiction, similar to drug addiction. More than half of respondents reported that treatment was necessary and almost three-quarters of respondents felt that problem gamblers would have to give up gambling completely in order to overcome their gambling problem. Problem gamblers (past or current) were less likely than non- or social gamblers to believe that treatment was needed, and current problem gamblers were least likely to believe that abstinence was required, as compared to all other respondents. Strong agreement with conceptions of gambling abuse as disease or addiction were positively associated with belief that treatment is needed, while strong agreement with conceptions of disease or wrongdoing were positively associated with belief that abstinence is required.
Predictors of Tobacco Use Among New York State Addiction Treatment Patients.
Guydish, Joseph; Yu, Jiang; Le, Thao; Pagano, Anna; Delucchi, Kevin
2015-01-01
Objectives. We used admissions data from the New York State addiction treatment system to assess patient self-reported tobacco use and factors associated with tobacco use. Methods. We compared prevalence of tobacco use in the state addiction treatment system with that of a national sample of people receiving addiction treatment and with that of the New York general population in 2005 to 2008. A random effects logistic model assessed relationships between patient- and program-level variables and tobacco use. Results. Prevalence of tobacco use in the New York treatment system was similar to that in national addiction treatment data and was 3 to 4 times higher than that in the general population. Co-occurring mental illness, opiate use, methadone treatment, and being a child of a substance-abusing parent were associated with higher rates of tobacco use. Conclusions. We call on federal leadership to build capacity to address tobacco use in addiction treatment, and we call on state leadership to implement tobacco-free grounds policies in addiction treatment systems.
Burnout in the working population: relations to psychosocial work factors.
Lindblom, Karin M; Linton, Steven J; Fedeli, Cecilia; Bryngelsson, Ing-Liss
2006-01-01
This study investigated levels of burnout in the general population irrespective of occupation and relations between burnout and psychosocial work factors. A cross-sectional survey featuring sleep problems, psychological distress, burnout (Maslach Burnout Inventory-General Survey), and psychosocial factors at work, was mailed to a random sample of 3,000 participants, aged 20-60. Response rate was 61%. A high level (18%), a low level (19%), and an intermediate group (63%) for burnout were constructed. The high level group was associated with those who were > 50 years old, women, those experiencing psychological distress, and those with a poor psychosocial work climate. The analyses on variables significant in previous analyses showed that the high level group was strongly related to high demands, low control, lack of social support, and disagreeing about values at the workplace even when accounting for age, gender, and psychological distress. We conclude that psychosocial work factors are important in association to burnout regardless of occupation.
Predictors of Tobacco Use Among New York State Addiction Treatment Patients
Yu, Jiang; Pagano, Anna; Delucchi, Kevin
2015-01-01
Objectives. We used admissions data from the New York State addiction treatment system to assess patient self-reported tobacco use and factors associated with tobacco use. Methods. We compared prevalence of tobacco use in the state addiction treatment system with that of a national sample of people receiving addiction treatment and with that of the New York general population in 2005 to 2008. A random effects logistic model assessed relationships between patient- and program-level variables and tobacco use. Results. Prevalence of tobacco use in the New York treatment system was similar to that in national addiction treatment data and was 3 to 4 times higher than that in the general population. Co-occurring mental illness, opiate use, methadone treatment, and being a child of a substance-abusing parent were associated with higher rates of tobacco use. Conclusions. We call on federal leadership to build capacity to address tobacco use in addiction treatment, and we call on state leadership to implement tobacco-free grounds policies in addiction treatment systems. PMID:25393179
Health Status of Individuals With Serious Mental Illness
Dickerson, Faith B.; Brown, Clayton H.; Daumit, Gail L.; LiJuan, Fang; Goldberg, Richard W.; Wohlheiter, Karen; Dixon, Lisa B.
2006-01-01
We examined indices of the health of persons with serious mental illness. A sample of 100 adults with schizophrenia and 100 with major mood disorder were recruited from randomly selected outpatients who were receiving community-based psychiatric treatment. Participants were surveyed about health indicators using items from the National Health and Nutrition Examination Study III and the National Health Interview Survey. Their responses were compared with those of matched samples from the general population surveys. A total of 1% of persons with serious mental illness, compared with 10% from the general population sample, met criteria for all 5 of selected health indicators: nonsmoker, exercise that meets recommended standards, good dentition, absence of obesity, and absence of serious medical co-occurring illness. Within the mentally ill group, educational level, but not a diagnosis of schizophrenia versus mood disorder, was independently associated with a composite measure of health behaviors. We conclude that an examination of multiple health indicators may be used to measure overall health status in persons with serious mental illness. PMID:16469943
Demographics of Australian horse owners: results from an internet-based survey.
Smyth, G B; Dagley, K
2015-12-01
To obtain information on the demographics of Australian horse owners. An invitation to participate in an opt-in, internet-based survey was sent to 7000 persons who had registered an email address to receive information from the Australian Horse Industry Council Inc. These horse owners represented approximately 1.75% of the total horse owners in Australia. The survey was available for completion between 1 and 31 July 2009. There were 3377 (48%) useable responses. The respondents were a self-selected group of approximately 0.85% of the estimated total horse owners in Australia. The overall geographic distribution of respondents was the same as the general population at a state and territory level. In general, respondents were female and aged between 31 and 60 years; most lived in rural areas of Queensland, New South Wales or Victoria; had at least a secondary education, but no formal horse industry qualification; had a higher weekly income if based in a capital city; earned less than 10% of weekly income from horse-related activities; were a member of more than one horse industry organisation; reported an affiliation with one of more than 300 different horse industry organisations; spent 10-30% of their daily time with horses; and preferred to receive information by email. The responses from this survey of horse owners provided demographic information that was previously unavailable. Horse owners tended to be older than the general population, had a higher level of education attainment, were in higher weekly income brackets and lived mostly in non-metropolitan areas of Australia. Because of the self-selection and small sample size, the results need to be interpreted with caution. Nevertheless, the present results are compatible with other smaller random and non-random surveys of horse owners internationally. © 2015 Australian Veterinary Association.
The use of propensity scores to assess the generalizability of results from randomized trials
Stuart, Elizabeth A.; Cole, Stephen R.; Bradshaw, Catherine P.; Leaf, Philip J.
2014-01-01
Randomized trials remain the most accepted design for estimating the effects of interventions, but they do not necessarily answer a question of primary interest: Will the program be effective in a target population in which it may be implemented? In other words, are the results generalizable? There has been very little statistical research on how to assess the generalizability, or “external validity,” of randomized trials. We propose the use of propensity-score-based metrics to quantify the similarity of the participants in a randomized trial and a target population. In this setting the propensity score model predicts participation in the randomized trial, given a set of covariates. The resulting propensity scores are used first to quantify the difference between the trial participants and the target population, and then to match, subclassify, or weight the control group outcomes to the population, assessing how well the propensity score-adjusted outcomes track the outcomes actually observed in the population. These metrics can serve as a first step in assessing the generalizability of results from randomized trials to target populations. This paper lays out these ideas, discusses the assumptions underlying the approach, and illustrates the metrics using data on the evaluation of a schoolwide prevention program called Positive Behavioral Interventions and Supports. PMID:24926156
Williamson, Graham R
2003-11-01
This paper discusses the theoretical limitations of the use of random sampling and probability theory in the production of a significance level (or P-value) in nursing research. Potential alternatives, in the form of randomization tests, are proposed. Research papers in nursing, medicine and psychology frequently misrepresent their statistical findings, as the P-values reported assume random sampling. In this systematic review of studies published between January 1995 and June 2002 in the Journal of Advanced Nursing, 89 (68%) studies broke this assumption because they used convenience samples or entire populations. As a result, some of the findings may be questionable. The key ideas of random sampling and probability theory for statistical testing (for generating a P-value) are outlined. The result of a systematic review of research papers published in the Journal of Advanced Nursing is then presented, showing how frequently random sampling appears to have been misrepresented. Useful alternative techniques that might overcome these limitations are then discussed. REVIEW LIMITATIONS: This review is limited in scope because it is applied to one journal, and so the findings cannot be generalized to other nursing journals or to nursing research in general. However, it is possible that other nursing journals are also publishing research articles based on the misrepresentation of random sampling. The review is also limited because in several of the articles the sampling method was not completely clearly stated, and in this circumstance a judgment has been made as to the sampling method employed, based on the indications given by author(s). Quantitative researchers in nursing should be very careful that the statistical techniques they use are appropriate for the design and sampling methods of their studies. If the techniques they employ are not appropriate, they run the risk of misinterpreting findings by using inappropriate, unrepresentative and biased samples.
Chang, Ye; Guo, Xiaofan; Guo, Liang; Li, Zhao; Yang, Hongmei; Yu, Shasha; Sun, Guozhe; Sun, Yingxian
2016-01-01
This study aimed to comprehensively compare the general characteristics, lifestyles, serum parameters, ultrasonic cardiogram (UCG) parameters, depression, quality of life, and various comorbidities between empty nest and non-empty nest elderly among rural populations in northeast China. This analysis was based on our previous study which was conducted from January 2012 to August 2013, using a multistage, stratified, random cluster sampling scheme. The final analyzed sample consisted of 3208 participants aged no less than 60 years, which was further classified into three groups: non-empty nest group, empty nest group (living as a couple), and empty nest group (living alone). More than half of the participants were empty nest elderly (60.5%). There were no significant statistical differences for serum parameters, UCG parameters, lifestyles, dietary pattern, and scores of Patient Health Questionnaire-9 (PHQ-9) and World Health Organization Quality of Life questionnaire, abbreviated version (WHOQOL-BREF) among the three groups. Empty nest elderly showed no more risk for comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, left atrial enlargement (LAE), and stroke. Our study indicated that empty nest elderly showed no more risk for depression, low quality of life and comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, LAE, and stroke among rural populations in northeast China. PMID:27618905
Chang, Ye; Guo, Xiaofan; Guo, Liang; Li, Zhao; Yang, Hongmei; Yu, Shasha; Sun, Guozhe; Sun, Yingxian
2016-08-27
This study aimed to comprehensively compare the general characteristics, lifestyles, serum parameters, ultrasonic cardiogram (UCG) parameters, depression, quality of life, and various comorbidities between empty nest and non-empty nest elderly among rural populations in northeast China. This analysis was based on our previous study which was conducted from January 2012 to August 2013, using a multistage, stratified, random cluster sampling scheme. The final analyzed sample consisted of 3208 participants aged no less than 60 years, which was further classified into three groups: non-empty nest group, empty nest group (living as a couple), and empty nest group (living alone). More than half of the participants were empty nest elderly (60.5%). There were no significant statistical differences for serum parameters, UCG parameters, lifestyles, dietary pattern, and scores of Patient Health Questionnaire-9 (PHQ-9) and World Health Organization Quality of Life questionnaire, abbreviated version (WHOQOL-BREF) among the three groups. Empty nest elderly showed no more risk for comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, left atrial enlargement (LAE), and stroke. Our study indicated that empty nest elderly showed no more risk for depression, low quality of life and comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, LAE, and stroke among rural populations in northeast China.
Rodríguez-Míguez, Eva; Mosquera Nogueira, Jacinto
To estimate the intangible effects of alcohol misuse on the drinker's quality of life, based on general population preferences METHODS: The most important effects (dimensions) were identified by means of two focus groups conducted with patients and specialists. The levels of these dimensions were combined to yield different scenarios. A sample of 300 people taken from the general Spanish population evaluated a subset of these scenarios, selected by using a fractional factorial design. We used the probability lottery equivalent method to derive the utility score for the evaluated scenarios, and the random-effects regression model to estimate the relative importance of each dimension and to derive the utility score for the rest of scenarios not directly evaluated. Four main dimensions were identified (family, physical health, psychological health and social) and divided into three levels of intensity. We found a wide variation in the utilities associated with the scenarios directly evaluated (ranging from 0.09 to 0.78). The dimensions with the greatest relative importance were physical health (36.4%) and family consequences (31.3%), followed by psychological (20.5%) and social consequences (11.8%). Our findings confirm the benefits of adopting a heterogeneous approach to measure the effects of alcohol misuse. The estimated utilities could have both clinical and economic applications. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.
Unhealthy lifestyle factors and depressive symptoms: A Japanese general adult population survey.
Furihata, Ryuji; Konno, Chisato; Suzuki, Masahiro; Takahashi, Sakae; Kaneita, Yoshitaka; Ohida, Takashi; Uchiyama, Makoto
2018-07-01
To investigate the relationship between unhealthy lifestyles factors and depressive symptoms among the general adult population in Japan. Participants were randomly selected from the Japanese general adult population. Data from 2334 people aged 20 years or older were analyzed. This cross-sectional survey was conducted in August and September 2009. Participants completed a face-to-face interview about unhealthy lifestyle factors, including lack of exercise, skipping breakfast, a poorly balanced diet, snacking between meals, insufficient sleep, current smoking, alcohol drinking, and obesity. Presence of depressive symptoms was defined as a score of ≥ 16 on the Japanese version of the Center for Epidemiologic Studies Depression Scale (CES-D). Relationships between unhealthy lifestyle factors and depressive symptoms were evaluated by multivariate logistic regression analysis adjusting for sociodemographic variables and other unhealthy lifestyle factors. Multivariate logistic regression analysis revealed that insufficient sleep, a poorly balanced diet, snacking between meals and lack of exercise were significantly associated with the prevalence of depressive symptoms, with odds ratios ranging from 1.56 for lack of exercise to 3.98 for insufficient sleep. Since this study was a cross-sectional study, causal relationships could not be determined. These results suggest that promoting a healthy lifestyle focused on sleep, food intake and exercise may be important for individuals with depressive symptoms. Copyright © 2018 Elsevier B.V. All rights reserved.
Risk factors for suicidal ideation of the general population.
Bae, Seung-Min; Lee, Yu Jin; Cho, In Hee; Kim, Seog Ju; Im, Jeong Soo; Cho, Seong-Jin
2013-04-01
The aim of this study was to investigate risk factors of suicide ideation in general population. A total of 1,116 adults were sampled with randomization in an urban area. After excluding 116 participants due to incomplete answer, 1,000 participants (500 males; mean age 39.6 ± 11.6) completed self-report questionnaire including the Center for Epidemiologic Study Depression Scale (CES-D), the Beck Scale for Suicide Ideation (BSI), the Spielberger State-Trait Anger Expression Inventory (STAXI), the Barratt Impulsiveness Scale (BIS), and questions on weekday sleep duration. Results showed higher scores on the BSI were related with higher scores on the STAXI, CES-D, a family history of psychiatric illness, and short or long sleep duration (≤ 5 or ≥ 10 hr) (adjusted R (2) = 0.151, P < 0.001, P < 0.001, P = 0.001, and P = 0.008, respectively). The predictive power of the STAXI scores, the presence of psychiatric family history and short or long sleep duration was stronger in the high CES-D group with scores of 16 or higher (adjusted R (2) = 0.275, P < 0.001, P < 0.001, and P < 0.001, respectively). These findings suggest that suicide idea in general population may be related with the presence of family history for psychiatric illness, depressive mood, high anger and short or long sleep duration.
Jiang, Wei; Mahnken, Jonathan D; He, Jianghua; Mayo, Matthew S
2016-11-01
For two-arm randomized phase II clinical trials, previous literature proposed an optimal design that minimizes the total sample sizes subject to multiple constraints on the standard errors of the estimated event rates and their difference. The original design is limited to trials with dichotomous endpoints. This paper extends the original approach to be applicable to phase II clinical trials with endpoints from the exponential dispersion family distributions. The proposed optimal design minimizes the total sample sizes needed to provide estimates of population means of both arms and their difference with pre-specified precision. Its applications on data from specific distribution families are discussed under multiple design considerations. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Werner, Natalie S; Duschek, Stefan; Schandry, Rainer
2009-12-01
The present study investigated whether the D-camphor-crataegus berry extract combination Korodin elevates blood pressure and enhances cognitive performance in the elderly population. Eighty women aged between 50 and 80 years were examined based on a randomized, placebo controlled double blind design. Blood pressure was measured sphygmomanometrically and through continuous noninvasive recording. Cognitive performance was assessed by means of two tests measuring general information processing capacity and visuomotor speed. The administration of the drug led to a short term increase in blood pressure as well as in cognitive performance as compared to placebo. Potential physiological mechanisms of action mediating this effect, including hemodynamic alterations, sympathetic stimulation as well as improvement of cerebral metabolism are discussed.
Mean-Potential Law in Evolutionary Games.
Nałęcz-Jawecki, Paweł; Miękisz, Jacek
2018-01-12
The Letter presents a novel way to connect random walks, stochastic differential equations, and evolutionary game theory. We introduce a new concept of a potential function for discrete-space stochastic systems. It is based on a correspondence between one-dimensional stochastic differential equations and random walks, which may be exact not only in the continuous limit but also in finite-state spaces. Our method is useful for computation of fixation probabilities in discrete stochastic dynamical systems with two absorbing states. We apply it to evolutionary games, formulating two simple and intuitive criteria for evolutionary stability of pure Nash equilibria in finite populations. In particular, we show that the 1/3 law of evolutionary games, introduced by Nowak et al. [Nature, 2004], follows from a more general mean-potential law.
Health Needs Assessment of Plain Populations in Lancaster County, Pennsylvania.
Miller, Kirk; Yost, Berwood; Abbott, Christina; Thompson, Scottie; Dlugi, Emily; Adams, Zachary; Schulman, Meryl; Strauss, Nicole
2017-02-01
We performed a health needs assessment for three Plain communities in Lancaster County, Pennsylvania from a random sample of households. Compared with the general population of adults, Plain respondents were more likely to be married, to have children, and they had large families; they were more likely to drink well water, to eat fruit and vegetables, to drink raw milk, and to live on a farm. Plain respondents had better physical and mental health and were less likely to have been diagnosed with various medical conditions compared with the general population of adults in Lancaster County but Old Order Mennonite respondents were more likely to have been diagnosed compared with Old Order Amish respondents. Plain respondents usually have a regular doctor and often receive preventive care but Old Order Mennonite respondents were more likely to have a regular doctor, to receive preventive care, to have had their children vaccinated, and to receive routine dental care compared with Old Order Amish respondents. Despite their relative geographic and genetic isolation, and despite the small, relative differences noted, the health of Plain communities in Lancaster County is similar to that of other adults in the County.
Shoulder strength value differences between genders and age groups.
Balcells-Diaz, Eudald; Daunis-I-Estadella, Pepus
2018-03-01
The strength of a normal shoulder differs according to gender and decreases with age. Therefore, the Constant score, which is a shoulder function measurement tool that allocates 25% of the final score to strength, differs from the absolute values but likely reflects a normal shoulder. To compare group results, a normalized Constant score is needed, and the first step to achieving normalization involves statistically establishing the gender differences and age-related decline. In this investigation, we sought to verify the gender difference and age-related decline in strength. We obtained a randomized representative sample of the general population in a small to medium-sized Spanish city. We then invited this population to participate in our study, and we measured their shoulder strength. We performed a statistical analysis with a power of 80% and a P value < .05. We observed a statistically significant difference between the genders and a statistically significant decline with age. To the best of our knowledge, this is the first investigation to study a representative sample of the general population from which conclusions can be drawn regarding Constant score normalization. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
Difficulties with telephone-based surveys on alcohol in high-income countries: the Canadian example
Shield, Kevin D.; Rehm, Jürgen
2012-01-01
Accurate information concerning alcohol consumption level and patterns is vital to formulating public health policy. The objective of this paper is to critically assess the extent to which survey design, response rate and alcohol consumption coverage obtained in random digit dialing, telephone-based surveys impact on conclusions about alcohol consumption and its patterns in the general population. Our analysis will be based on the Canadian Alcohol and Drug Use Monitoring Survey (CADUMS) 2008, a national survey intended to be representative of the general population. The conclusions of this paper are as follows: 1) ignoring people who are homeless, institutionalized and/or do not have a home phone may lead to an underestimation of the prevalence of alcohol consumption and related problems; 2) weighting of observations to population demographics may lead to a increase in the design effect, does not necessarily address the underlying selection bias, and may lead to overly influential observations; and 3) the accurate characterization of alcohol consumption patterns obtained by triangulating the data with the adult per capita consumption estimate is essential for comparative analyses and intervention planning especially when the alcohol coverage rate is low like in the CADUMS with 34%. PMID:22337654
Dietary Sodium and Blood Pressure: How Low Should We Go?
Van Horn, Linda
2015-01-01
Sodium intake in the United States exceeds recommended amounts across all age, gender and ethnic groups. National dietary guidelines advocate reduced intake by at least 1,000mg per day or more, but whether there is population-wide benefit from further reductions to levels of 1500mg per day remains controversial. A brief review of current evidence-based dietary guidelines is provided and key prospective, randomized studies that report dietary and urinary sodium data are summarized. Dietary sources of sodium and eating patterns that offer nutritiously sound approaches to nutrient dense, reduced sodium intake are compared. No studies suggest that high sodium intake at the levels of the population's current diet is optimal. On the contrary, national and international evidence and systematic reviews consistently recommend reducing sodium intake overall, generally by 1000mg/day. Recommendations to reduce intakes to 2400mg/d are generally accepted as beneficial. Whether further reductions to 1500mg/d are useful, feasible and safe among specific subgroups in the population who are at increased risk of hypertension or stroke remains controversial and requires individualized consideration by patients and their health care providers. Copyright © 2015 Elsevier Inc. All rights reserved.
Campagna, Marcello; Satta, Giannina; Campo, Laura; Flore, Valeria; Ibba, Antonio; Meloni, Michele; Tocco, Maria Giuseppina; Avataneo, Giuseppe; Flore, Costantino; Fustinoni, Silvia; Cocco, Pierluigi
2014-01-01
Analytical difficulties and lack of a biological exposure index and reference values have prevented using unmetabolized urinary benzene (UB) excretion as a biomarker of low-level environmental exposure. To explore what environmental factors beyond active smoking may contribute to environmental exposure to benzene, we monitored UB excretion in a non-smoking, non-occupationally exposed sample of the general population. Two spot urine samples were obtained from 86 non-smoking, non-occupationally exposed subjects, selected among a random sample of the general population of the metropolitan area of Cagliari (Sardinia, Italy), at 8:00 a.m. (UBm) and 8:00 p.m. (UBe). UB was measured by headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry analysis. Questionnaire information on personal and environmental exposures during the sampling day was gathered with personal interviews. Multivariate analysis of variance and multiple regression model were applied to investigate the role of such variables on the level of UB. The ninety-fifth percentile of UBe in this population was 311.5 ng/L, which is tentatively proposed as the UB guidance value for unexposed populations. UBm and urban residence were the only predictors of a significant increase in UBe excretion. Self-reported residential vehicular traffic will not account for the excess median value among urban residents; commuting time among urban residents showed a suggestive nonsignificant linear correlation with UBe, but the small sample size prevented reliable inference to be drawn. Age, environmental tobacco smoking, employment status and body mass index did not affect UB excretion. Our findings support the use of unmetabolized UB as a specific and sensitive biomarker of low-level environmental exposure to benzene.
Van daele, Caroline M; De Meyer, Tim; De Buyzere, Marc L; Gillebert, Thierry C; Denil, Simon L I J; Bekaert, Sofie; Chirinos, Julio A; Segers, Patrick; De Backer, Guy G; De Bacquer, Dirk; Rietzschel, Ernst R
2013-01-01
Whereas the importance of family history (FH) is widely recognized in cardiovascular risk assessment, its full potential could be underutilized, when applied with its current simple guidelines-based definition (cFH): presence of premature cardiovascular disease (CVD) in a first-degree relative. We tested the added value of a new, extended family history definition (eFH), also taking into account later onset of disease, second-degree relatives and number of affected relatives, on profiling cardiovascular risk and atherosclerotic burden in the general population. Longitudinal population study. Random, representative population sample from Erpe-Mere and Nieuwerkerken (Belgium, primary care). 2524 male/female volunteers, aged 35-55 years, free from overt CVD. Subjects were extensively phenotyped including presence of atherosclerosis (ultrasound) and a newly developed FH questionnaire (4 generations). Compared to cFH, eFH was superior in predicting an adverse risk profile (glycemic state, elevated blood pressure, lipid abnormalities, presence of metabolic syndrome components) and presence of atherosclerosis (all age & sex-adjusted p<0.05). Unlike cFH, eFH remained a significant predictor of subclinical atherosclerosis after adjusting for confounders. Most relations with eFH were not graded but showed clear informational breakpoints, with absence of CVD (including late onset) in any first-degree relative being a negative predictor of atherosclerosis, and a particularly interesting phenotype for further study. A novel, extended FH definition is superior to the conventional definition in profiling cardiovascular risk and atherosclerotic burden in the general population. There remain clear opportunities to refine and increase the performance and informational content of this simple, readily-available inexpensive tool.
Rodríguez-Roca, G C; Rodríguez-Padial, L; Alonso-Moreno, F J; Segura-Fragoso, A; Villarín-Castro, A; Rodríguez-García, M L; Menchén-Herreros, A; Rojas-Martelo, G A; Fernández-Conde, J A; Artigao-Rodenas, L M; Carbayo-Herencia, J A; Escobar-Cervantes, C; Hernández-Moreno, J; Fernández-Martín, J
2018-03-01
The main aim of this study is to ascertain the prevalence of cardiovascular risk factors (CVRF), target organ damage (TOD), cardiovascular disease (CVD), as well as life habits (physical exercise, alcohol consumption, and Mediterranean diet) in the population of a Health Area in Toledo, Spain, to assess cardiovascular risk (CVR). Epidemiological and observational study that will analyse a sample from the general population aged 18 years or older, randomly selected from a database of health cards, and stratified by age and gender. Clinical history, physical examination, and complementary tests will be performed. Aliquots of whole blood and serum samples will be stored at a temperature of-85°C to evaluate future genetic studies. CVR will be estimated by using SCORE project scales calibrated for Spanish population and the Framingham Heart Study scale. When the estimated sample size has been achieved and after a minimum follow-up of 5 years, a final visit will performed in which CVRF, TOD, CVD, CVRF control, and fatal and non-fatal outcomes will be evaluated. The RICARTO study is aimed to assess the prevalence of the main CVRF, TOD and CVD in order to determine the CVR in the general population of a health area of Toledo. An analysis will be repeated on the final sample after at least 5 years of follow-up to ascertain the incidence of CV outcomes and the temporal trends of life style, as well as the prevalence of CVRF, TOD, and CVD. Copyright © 2017 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.
Samano, Ninos; Bodin, Lennart; Karlsson, Jan; Geijer, Håkan; Arbeus, Mikael; Souza, Domingos
2017-03-01
The objective of this study was to investigate whether graft patency was associated with higher health-related quality of life in coronary artery bypass grafting patients and to compare this study with the general Swedish population. Patients were included from 3 randomized trials and 1 prospective cohort trial. The generic health-related quality of life instrument, EQ-5D (VAS and index) was used. Graft patency was assessed with computed tomography angiography. Patients were divided into 2 groups according to the number of occluded distal anastomosis: Group I with no to 1 occlusion ( n = 209) and Group II with 2 to 4 occlusions ( n = 24). Two hundred and thirty-three patients underwent computed tomography angiography at a mean of 7.5 (1-18) years post-operatively. The mean difference in EQ-VAS and EQ-5D index between Groups II and I after model adjustment was -19.8 (95% CI -25.3 to -14.3; P < 0.001) and -0.13 (95% CI -0.19 to -0.08; P < 0.001), respectively. The EQ-5D index for the study population was similar compared with the Swedish population, 0.851 and 0.832, respectively, with an effect-size of 0.112 (trivial). The EQ-5D index of the study population was higher compared with the ischemic heart disease group in the Swedish population, 0.851 vs 0.60, with an effect-size of 0.999 (large). Graft patency was associated with higher health-related quality of life in coronary artery bypass patients. This patient group reported similar function and wellbeing compared to the general Swedish population and better health status than those in the same disease group in the general population. Clinicaltrials.gov: NCT02547194 and the Research and Development registry in Sweden: 167861. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
Trend estimation in populations with imperfect detection
Kery, Marc; Dorazio, Robert M.; Soldaat, Leo; Van Strien, Arco; Zuiderwijk, Annie; Royle, J. Andrew
2009-01-01
1. Trends of animal populations are of great interest in ecology but cannot be directly observed owing to imperfect detection. Binomial mixture models use replicated counts to estimate abundance, corrected for detection, in demographically closed populations. Here, we extend these models to open populations and illustrate them using sand lizard Lacerta agilis counts from the national Dutch reptile monitoring scheme. 2. Our model requires replicated counts from multiple sites in each of several periods, within which population closure is assumed. Counts are described by a hierarchical generalized linear model, where the state model deals with spatio-temporal patterns in true abundance and the observation model with imperfect counts, given that true state. We used WinBUGS to fit the model to lizard counts from 208 transects with 1–10 (mean 3) replicate surveys during each spring 1994–2005. 3. Our state model for abundance contained two independent log-linear Poisson regressions on year for coastal and inland sites, and random site effects to account for unexplained heterogeneity. The observation model for detection of an individual lizard contained effects of region, survey date, temperature, observer experience and random survey effects. 4. Lizard populations increased in both regions but more steeply on the coast. Detectability increased over the first few years of the study, was greater on the coast and for the most experienced observers, and highest around 1 June. Interestingly, the population increase inland was not detectable when the observed counts were analysed without account of detectability. The proportional increase between 1994 and 2005 in total lizard abundance across all sites was estimated at 86% (95% CRI 35–151). 5. Synthesis and applications. Open-population binomial mixture models are attractive for studying true population dynamics while explicitly accounting for the observation process, i.e. imperfect detection. We emphasize the important conceptual benefit provided by temporal replicate observations in terms of the interpretability of animal counts.
Echouffo-Tcheugui, Justin B; Simmons, Rebecca K; Prevost, A Toby; Williams, Kate M; Kinmonth, Ann-Louise; Wareham, Nicholas J; Griffin, Simon J
2015-03-01
There is limited trial evidence concerning the long-term effects of screening for type 2 diabetes on population morbidity. We examined the effect of a population-based diabetes screening program on cardiovascular morbidity, self-rated health, and health-related behaviors. We conducted a pragmatic, parallel-group, cluster-randomized controlled trial of diabetes screening (the ADDITION-Cambridge study) including 18,875 individuals aged 40 to 69 years at high risk of diabetes in 32 general practices in eastern England (27 practices randomly allocated to screening, 5 to no-screening for control). Of those eligible for screening, 466 (2.9%) were diagnosed with diabetes. Seven years after randomization, a random sample of patients was sent a postal questionnaire: 15% from the screening group (including diabetes screening visit attenders and non-attenders) and 40% from the no-screening control group. Self-reported cardiovascular morbidity, self-rated health (using the SF-8 Health Survey and EQ-5D instrument), and health behaviors were compared between trial groups using an intention-to-screen analysis. Of the 3,286 questionnaires mailed out, 1,995 (61%) were returned, with 1,945 included in the analysis (screening: 1,373; control: 572). At 7 years, there were no significant differences between the screening and control groups in the proportion of participants reporting heart attack or stroke (OR = 0.90, 95% CI, 0.71-1.15); SF-8 physical health summary score as an indicator of self-rated health status (β -0.33, 95% CI, -1.80 to 1.14); EQ-5D visual analogue score (β: 0.80, 95% CI, -1.28 to 2.87); total physical activity (β 0.50, 95% CI, -4.08 to 5.07); current smoking (OR 0.97, 95% CI, 0.72 to 1.32); and alcohol consumption (β 0.14, 95% CI, -1.07 to 1.35). Invitation to screening for type 2 diabetes appears to have limited impact on population levels of cardiovascular morbidity, self-rated health status, and health behavior after 7 years. © 2015 Annals of Family Medicine, Inc.
Echouffo-Tcheugui, Justin B.; Simmons, Rebecca K.; Prevost, A. Toby; Williams, Kate M.; Kinmonth, Ann-Louise; Wareham, Nicholas J.; Griffin, Simon J.
2015-01-01
PURPOSE There is limited trial evidence concerning the long-term effects of screening for type 2 diabetes on population morbidity. We examined the effect of a population-based diabetes screening program on cardiovascular morbidity, self-rated health, and health-related behaviors. METHODS We conducted a pragmatic, parallel-group, cluster-randomized controlled trial of diabetes screening (the ADDITION-Cambridge study) including 18,875 individuals aged 40 to 69 years at high risk of diabetes in 32 general practices in eastern England (27 practices randomly allocated to screening, 5 to no-screening for control). Of those eligible for screening, 466 (2.9%) were diagnosed with diabetes. Seven years after randomization, a random sample of patients was sent a postal questionnaire: 15% from the screening group (including diabetes screening visit attenders and non-attenders) and 40% from the no-screening control group. Self-reported cardiovascular morbidity, self-rated health (using the SF-8 Health Survey and EQ-5D instrument), and health behaviors were compared between trial groups using an intention-to-screen analysis. RESULTS Of the 3,286 questionnaires mailed out, 1,995 (61%) were returned, with 1,945 included in the analysis (screening: 1,373; control: 572). At 7 years, there were no significant differences between the screening and control groups in the proportion of participants reporting heart attack or stroke (OR = 0.90, 95% CI, 0.71–1.15); SF-8 physical health summary score as an indicator of self-rated health status (β −0.33, 95% CI, −1.80 to 1.14); EQ-5D visual analogue score (β: 0.80, 95% CI, −1.28 to 2.87); total physical activity (β 0.50, 95% CI, −4.08 to 5.07); current smoking (OR 0.97, 95% CI, 0.72 to 1.32); and alcohol consumption (β 0.14, 95% CI, −1.07 to 1.35). CONCLUSIONS Invitation to screening for type 2 diabetes appears to have limited impact on population levels of cardiovascular morbidity, self-rated health status, and health behavior after 7 years. PMID:25755036
Fernandez-Mendoza, Julio; Vgontzas, Alexandros N.; Bixler, Edward O.; Singareddy, Ravi; Shaffer, Michele L.; Calhoun, Susan L.; Karataraki, Maria; Vela-Bueno, Antonio; Liao, Duanping
2012-01-01
Study Objectives: Approximately 8-10% of the general population suffers from chronic insomnia, whereas another 20-30% of the population has insomnia symptoms at any given time (i.e., poor sleep). However, few longitudinal studies have examined risk factors of the natural history of poor sleep, and none have examined the role of polysomnographic (PSG) variables. Design: Representative longitudinal study. Setting: Sleep laboratory. Participants: From a random, general population sample of 1,741 individuals of the adult Penn State Cohort, 1,395 were followed up after 7.5 yr. Measurements: Full medical evaluation and 1-night PSG at baseline and telephone interview at follow-up. Results: The rate of incident poor sleep was 18.4%. Physical (e.g., obesity, sleep apnea, and ulcer) and mental (e.g., depression) health conditions and behavioral factors (e.g., smoking and alcohol consumption) increased the odds of incident poor sleep as compared to normal sleep. The rates of persistent, remitted, and poor sleepers who developed chronic insomnia were 39%, 44%, and 17%, respectively. Risk factors for persistent poor sleep were physical health conditions combined with psychologic distress. Shorter objective sleep duration and a family history of sleep problems were risk factors for poor sleep evolving into chronic insomnia. Conclusions: Poor sleep appears to be primarily a symptom of physical and mental health conditions, whereas the persistence of poor sleep is associated with psychologic distress. Importantly, sleep apnea appears to be associated with incident poor sleep but not with chronic insomnia. Finally, this study suggests that objective short sleep duration in poor sleepers is a biologic marker of genetic predisposition to chronic insomnia. Citation: Fernandez-Mendoza J; Vgontzas AN; Bixler EO; Singareddy R; Shaffer ML; Calhoun SL; Karataraki M; Vela-Bueno A; Liao D. Clinical and polysomnographic predictors of the natural history of poor sleep in the general population. SLEEP 2012;35(5):689-697. PMID:22547895
Predictors of psychological distress in low-income populations of Montreal.
Caron, Jean; Latimer, Eric; Tousignant, Michel
2007-01-01
THEORETICAL PERSPECTIVE: Many epidemiologic studies agree that low-income populations are the groups most vulnerable to mental health problems. However, not all people in economic difficulty show symptoms, and it appears that having a social support network plays a role in protecting against the chronic stress resulting from conditions such as poverty. The aim of the study is to clarify the relative contribution of social support to the mental health of low-income populations in two neighbourhoods in the southwest of Montreal: Pointe-Saint Charles and Saint-Henri. A random sample of 416 social assistance recipients in southwest Montreal and another sample of 112 people, drawn at random from the general population, were interviewed. The psychological distress scale used was the Indice de détresse psychologique--Enquête Santê Quêbec (IDPESQ). The availability of social support components was assessed by using the Social Provisions Scale. Data were collected during interviews in the respondents' homes. Social support measures were entered into a multidimensional model including many variables identified as being associated with mental health. Multiple regression analysis identified the best predictors of psychological distress for the low-income population. Among the 30 variables included in a multiple regression analysis, emotional support and the presence of persons perceived as stressful together accounted for most of the variance in distress predicted by the model. Although younger people, people experiencing food insecurity and people with poorer numeracy show a higher level of distress, these variables make a fairly marginal contribution compared with that of social relations.
Krukowski, Rebecca A.; Hare, Marion E.; Talcott, Gerald W.; Johnson, Karen C.; Richey, Phyllis A.; Kocak, Mehmet; Balderas, Jennifer; Colvin, Lauren; Keller, Patrick L.; Waters, Teresa M.; Klesges, Robert C.
2014-01-01
Despite an increase in overweight and obesity similar to the civilian population, there have been few randomized controlled trials examining behavioral weight management interventions in the military settings. This paper describes the design, intervention development and analysis plan of the Fit Blue study, a randomized controlled behavioral weight loss trial taking place in the United States Air Force. This study compares two adapted versions of the efficacious Look AHEAD Intensive Lifestyle Intervention (ILI), a counselor-initiated condition and a self-paced condition. Also described are the unique steps required when conducting military-based health promotion research and adaptations made to the Look AHEAD intervention to accommodate the military environment. To our knowledge, this is the first translation of the Look AHEAD ILI in the military setting and one of the first translations of the ILI in general. If successful, this intervention could be disseminated to the entire U.S. Military as this project is designed to overcome the barriers and utilize the facilitators for weight loss that are unique to a military population. Programs validated in military populations can have a major public health impact given that with 1.4 million active duty personnel, the Department of Defense is the nation’s largest employer. However, while this intervention is designed for a military population and there are unique aspects of the military that may enhance weight loss interventions, the diversity of the study population should help inform obesity efforts in both civilian and military settings. PMID:25545025
Krukowski, Rebecca A; Hare, Marion E; Talcott, Gerald W; Johnson, Karen C; Richey, Phyllis A; Kocak, Mehmet; Balderas, Jennifer; Colvin, Lauren; Keller, Patrick L; Waters, Teresa M; Klesges, Robert C
2015-01-01
Despite an increase in overweight and obesity similar to the civilian population, there have been few randomized controlled trials examining behavioral weight management interventions in the military settings. This paper describes the design, intervention development and analysis plan of the Fit Blue study, a randomized controlled behavioral weight loss trial taking place in the United States Air Force. This study compares two adapted versions of the efficacious Look AHEAD Intensive Lifestyle Intervention (ILI), a counselor-initiated condition and a self-paced condition. Also described are the unique steps required when conducting military-based health promotion research and adaptations made to the Look AHEAD intervention to accommodate the military environment. To our knowledge, this is the first translation of the Look AHEAD ILI in the military setting and one of the first translations of the ILI in general. If successful, this intervention could be disseminated to the entire U.S. Military as this project is designed to overcome the barriers and utilize the facilitators for weight loss that are unique to a military population. Programs validated in military populations can have a major public health impact given that with 1.4 million active duty personnel, the Department of Defense is the nation's largest employer. However, while this intervention is designed for a military population and there are unique aspects of the military that may enhance weight loss interventions, the diversity of the study population should help inform obesity efforts in both civilian and military settings. Copyright © 2014 Elsevier Inc. All rights reserved.
Le Guen, Morgan; Herr, Marie; Bizard, Antoine; Bichon, Caroline; Boichut, Nathalie; Chazot, Thierry; Liu, Ngai; Ankri, Joel; Fischler, Marc
2017-03-16
Currently, patients older than 60 years of age represent 25% of the population and are at an increased risk during surgery. Therefore, reducing postoperative morbidity and mortality is a major concern in medical research and practice. Dependence on caregivers and cognitive impairment represent two major risk factors in the elderly, especially in frail patients after surgery under general anesthesia. In this context, continuous monitoring of the depth of anesthesia using a bispectral index (BIS) sensor may reduce the occurrence of impairments by gaining better control of the anesthetic depth. The first aim of this study is to compare manual versus automated administration of intravenous anesthetics with regard to 6-month functional decline in persons aged 70 years and older. The secondary objective includes an evaluation of the influence of the frail phenotype on self-sufficiency in elderly patients after general anesthesia. After receiving ethical committee approval and written consent, a complete preoperative assessment of physiological reserve and self-sufficiency will be performed on patients more than 70 years old who are scheduled for surgery under general anesthesia. This evaluation will determine the patient's frailty status in three categories: robust, pre-frail, and frail. Then, patients will be randomized into two groups: manual administration of anesthetics guided by BIS sensor (manual group) or automated administration (automated group) with recording of the anesthesia. A second examination will be scheduled after 6 months to assess changes in functional abilities, cognitive functions, and frailty status. A priori calculation of sample size gives a population of 430 patients to be included in this multicenter trial. This clinical study is designed to detect any postoperative complications and deaths related to the performance of the general anesthesia guided by the BIS sensor and the preoperative functional status of the elderly: robust, pre-frail, or frail. ClinicalTrials.gov, NCT02524327 . Registered on 10 August 2015.
Lin, Feng-Cheng; Chuang, Yun-Shiuan; Hsieh, Hui-Min; Lee, Tzu-Chi; Chiu, Kuei-Fen; Liu, Ching-Kuan; Wu, Ming-Tsang
2015-11-01
The protective effect of statin on Alzheimer disease (AD) is still controversial, probably due to the debate about when to start the use of statin and the lack of any large-scale randomized evidence that actually supports the hypothesis. The purpose of this study was to examine the protective effect of early statin use on mild-to-moderate AD in the total Taiwanese population.This was a total population-based case-control study, using the total population of Taiwanese citizens seen in general medical practice; therefore, the findings can be applied to the general population. The study patients were those with newly diagnosed dementia (ICD-9 290.x) and prescribed any acetylcholinesterase inhibitors (AChEI) from the Taiwan National Health Insurance dataset in 1997 to 2008. The newly diagnosed eligible mild-to-moderate AD patients were traced from the dates of their index dates, which was defined as the first day to receive any AChEI treatment, back to 1 year (exposure period) to categorize them into AD with early statin use and without early statin use. Early statin use was defined as patients using statin before AChEI treatment. Alzheimer disease patients with early statin use were those receiving any statin treatment during the exposure period. Then, we used propensity-score-matched strategy to match these 2 groups as 1:1. The matched study patients were followed-up from their index dates. The primary outcome was the discontinuation of AChEI treatment, indicating AD progression.There were 719 mild-to-moderate AD-paired patients with early statin use and without early statin use for analyses. Alzheimer disease progression was statistically lower in AD patients with early statin use than those without (P = 0.00054). After adjusting for other covariates, mild-to-moderate AD patients with early stain use exhibited a 0.85-risk (95% CI = 0.76-0.95, P = 0.0066) to have AD progression than those without.Early statin use was significantly associated with a reduction in AD progression in mild-to-moderate AD patients. The future randomized trial studies can confirm our findings.
Otero, Alfonso; Gayoso, Pilar; Garcia, Fernando; de Francisco, Angel L
2005-12-01
Chronic kidney disease (CKD) is a major social health problem because of the aging of the population, the high incidence of diabetes mellitus, and the epidemic of silent CKD resulting from inadequate diagnosis of early chronic renal insufficiency The sociodemographic, baseline characteristics and CKD prevalence measured by the Modification of Diet in Renal Disease formula were studied in a randomly selected sample of people aged 20 years or older in the general population. We report the results of the analysis of the EPIRCE (Estudio Epidemiológico de la Insuficiencia Renal en España) pilot study performed in Galicia, Spain, in the last quarter of 2004. Baseline characteristics, sociodemographic characteristics, and results of a clinical examination and blood variables were collected from 237 patients who fulfilled the study's inclusion and exclusion criteria. The mean age of the sample was 49.58 years (95% confidence interval, 47.39-51.76). The prevalence of Kidney Disease Outcomes Quality Initiative grade 3 CKD was 5.1%, but the coexistence of an albumin/creatinine ratio>30 mg/g with grade 1 to 2 CKD raised the final rate to 12.7% in this population. We found a high prevalence of hypertension (31.5%), isolated systolic hypertension (20.1%), diabetes mellitus (8%), obesity (13.1%), smoking habit (22.7%), high atherogenic index (30.8%), and high alcohol intake (24%). Risk factors significantly associated with renal disease were age [P=0.018; odds ratio (OR) 2.7], hypertension (P=0.023; OR 2.13), pulse pressure (P=0.04; OR 0.10), diabetes mellitus (P=0.08; OR 4.48), obesity (P=0.000; OR 7.7), and insulin resistance index (P=0.04; OR 4.95). The prevalence of CKD and conventional cardiovascular risk factors is high in this randomly selected sample of the general population. Secondary preventive measures are needed to detect chronic kidney impairment as early as possible and to reduce the incidence and mortality arising from the associated comorbidities.
Uric acid and progression of chronic kidney disease.
Weaver, Donald J
2018-06-21
The association between serum uric acid levels and human disease has garnered intense interest over the last decade including chronic kidney disease. Animal studies have provided evidence for a potential mechanistic role of uric acid in promoting progression of chronic kidney disease. Epidemiologic studies have also suggested an association between elevated serum uric acid levels and worsening renal function in the general population as well as in patients with chronic kidney disease. However, there is currently insufficient evidence to recommend the use of uric acid-lowering therapy to delay progression of chronic kidney disease in this patient population. Adequately powered, randomized, placebo-controlled trials are required to more precisely evaluate the risk and benefits of uric acid-lowering therapy in pediatric patients.
Navarro, B; Daròs, J A; Flores, R
1996-01-01
Two PCR-based methods are described for obtaining clones of small circular RNAs of unknown sequence and for which only minute amounts are available. To avoid introducing any assumption about the RNA sequence, synthesis of the cDNAs is initiated with random primers. The cDNA population is then PCR-amplified using a primer whose sequence is present at both sides of the cDNAs, since they have been obtained with random hexamers and then a linker with the sequence of the PCR primer has been ligated to their termini, or because the cDNAs have been synthesized with an oligonucleotide that contains the sequence of the PCR primer at its 5' end and six randomized positions at its 3' end. The procedures need only approximately 50 ng of purified RNA template. The reasons for the emergence of cloning artifacts and precautions to avoid them are discussed.
Imamura, Kotaro; Kawakami, Norito; Furukawa, Toshi A; Matsuyama, Yutaka; Shimazu, Akihito; Umanodan, Rino; Kawakami, Sonoko; Kasai, Kiyoto
2015-05-01
This study reported a randomized controlled trial of the effectiveness of an Internet-based cognitive behavioral therapy (iCBT) program on work engagement and secondary work-related outcomes. Participants who fulfilled the inclusion criteria were randomly allocated to an intervention or a control group (N = 381 for each). A 6-week, 6-lesson iCBT program using a Manga (Japanese comic) story was provided only to the intervention group. Work engagement was assessed at baseline and at 3- and 6-month follow-ups for both groups. The iCBT program showed a significant intervention effect on work engagement (P = 0.04) with small effect sizes (Cohen's d = 0.16 at 6-month follow-up). The study showed computerized cognitive behavior therapy delivered via the Internet to be effective (with a small effect size) in increasing work engagement in the general working population. UMIN Clinical Trials Registry (UMIN-CTR) UMIN000006210.
Random catalytic reaction networks
NASA Astrophysics Data System (ADS)
Stadler, Peter F.; Fontana, Walter; Miller, John H.
1993-03-01
We study networks that are a generalization of replicator (or Lotka-Volterra) equations. They model the dynamics of a population of object types whose binary interactions determine the specific type of interaction product. Such a system always reduces its dimension to a subset that contains production pathways for all of its members. The network equation can be rewritten at a level of collectives in terms of two basic interaction patterns: replicator sets and cyclic transformation pathways among sets. Although the system contains well-known cases that exhibit very complicated dynamics, the generic behavior of randomly generated systems is found (numerically) to be extremely robust: convergence to a globally stable rest point. It is easy to tailor networks that display replicator interactions where the replicators are entire self-sustaining subsystems, rather than structureless units. A numerical scan of random systems highlights the special properties of elementary replicators: they reduce the effective interconnectedness of the system, resulting in enhanced competition, and strong correlations between the concentrations.
Naldi, Luigi; Cazzaniga, Simone; Gonçalo, Margarida; Diepgen, Thomas; Bruze, Magnus; Elsner, Peter; Coenraads, Peter J; Svensson, Åke; Bertuccio, Paola; Ofenloch, Robert
2014-02-01
IMPORTANCE Skin disorders are common in the general population, and they may be associated with significant disability. The use of daily skin products may affect the appearance and severity of skin conditions. OBJECTIVES To assess the prevalence of reported itchy rash lasting longer than 3 days among the general population and to evaluate lifetime avoidance of different types of consumer products because of skin problems. DESIGN, SETTING, AND PARTICIPANTS The European Dermato-Epidemiology Network (EDEN) Fragrance Study comprised a large descriptive epidemiological survey of the general population conducted in 6 European regions from August 20, 2008, to October 10, 2011. Participants were a random sample of individuals aged 18 to 74 years, based on electoral precincts. The participants were interviewed using a standardized questionnaire. EXPOSURES Lifetime exposure to products of common use was considered, including toiletry items that remained on the skin or were rinsed off and household and functional items. MAIN OUTCOMES AND MEASURES The 1-month, 1-year, and lifetime age-standardized prevalence rates of itchy rash that lasted longer than 3 days. RESULTS In total, 12 377 individuals (53.9% female; median age, 43 years) were interviewed. The overall prevalences of itchy rash were 19.3% (95% CI, 18.6%-20.0%) during the month preceding the interview, 31.8% (95% CI, 31.0%-32.6%) during the preceding year, and 51.7% (95% CI, 50.8%-52.6%) over a lifetime. In addition, the percentage of individuals who reported avoidance of any product varied from 37.0% for products intended to be left on the skin to 17.7% for household or functional products. CONCLUSIONS AND RELEVANCE Our findings confirmed the magnitude of skin problems among the general population reported in other surveys. Although itchy rash is a nonspecific manifestation, it may be considered in epidemiological surveys to reflect a constellation of skin conditions and to summarize the burden of these conditions on general health.
van Riet, Evelien E S; Hoes, Arno W; Limburg, Alexander; van der Hoeven, Henk; Landman, Marcel A J; Rutten, Frans H
2014-01-08
Most patients with heart failure are diagnosed and managed in primary care, however, underdiagnosis and undertreatment are common. We assessed whether implementation of a diagnostic-therapeutic strategy improves functionality, health-related quality of life, and uptake of heart failure medication in primary care. A selective screening study followed by a single-blind cluster randomized trial in primary care. The study population consists of patients aged 65 years or over who presented themselves to the general practitioner in the previous 12 months with shortness of breath on exertion. Patients already known with established heart failure, confirmed by echocardiography, are excluded. Diagnostic investigations include history taking, physical examination, electrocardiography, and serum N-terminal pro B-type natriuretic peptide levels. Only participants with an abnormal electrocardiogram or an N-terminal pro B-type natriuretic peptide level exceeding the exclusionary cutpoint for non-acute onset heart failure (> 15 pmol/L (≈ 125 pg/ml)) will undergo open-access echocardiography. The diagnosis of heart failure (with reduced or preserved ejection fraction) is established by an expert panel consisting of two cardiologists and a general practitioner, according to the criteria of the European Society of Cardiology guidelines.Patients with newly established heart failure are allocated to either the 'care as usual' group or the 'intervention' group. Randomization is at the level of the general practitioner. In the intervention group general practitioners receive a single half-day training in heart failure management and the use of a structured up-titration scheme. All participants fill out quality of life questionnaires at baseline and after six months of follow-up. A six-minute walking test will be performed in patients with heart failure. Information on medication and hospitalization rates is extracted from the electronic medical files of the general practitioners. This study will provide information on the prevalence of unrecognized heart failure in elderly with shortness of breath on exertion, and the randomized comparison will reveal whether management based on a half-day training of general practitioners in the practical application of an up-titration scheme results in improvements in functionality, health-related quality of life, and uptake of heart failure medication in heart failure patients compared to care as usual. ClinicalTrials.gov NCT01202006.
Trans-algorithmic nature of learning in biological systems.
Shimansky, Yury P
2018-05-02
Learning ability is a vitally important, distinctive property of biological systems, which provides dynamic stability in non-stationary environments. Although several different types of learning have been successfully modeled using a universal computer, in general, learning cannot be described by an algorithm. In other words, algorithmic approach to describing the functioning of biological systems is not sufficient for adequate grasping of what is life. Since biosystems are parts of the physical world, one might hope that adding some physical mechanisms and principles to the concept of algorithm could provide extra possibilities for describing learning in its full generality. However, a straightforward approach to that through the so-called physical hypercomputation so far has not been successful. Here an alternative approach is proposed. Biosystems are described as achieving enumeration of possible physical compositions though random incremental modifications inflicted on them by active operating resources (AORs) in the environment. Biosystems learn through algorithmic regulation of the intensity of the above modifications according to a specific optimality criterion. From the perspective of external observers, biosystems move in the space of different algorithms driven by random modifications imposed by the environmental AORs. A particular algorithm is only a snapshot of that motion, while the motion itself is essentially trans-algorithmic. In this conceptual framework, death of unfit members of a population, for example, is viewed as a trans-algorithmic modification made in the population as a biosystem by environmental AORs. Numerous examples of AOR utilization in biosystems of different complexity, from viruses to multicellular organisms, are provided.
Belhaj, K; Meftah, S; Mahir, L; Lmidmani, F; Elfatimi, A
2016-11-01
This study aims to compare the isokinetic profile of hip abductor and adductor muscle groups between soccer players suffering from chronic adductor-related groin pain (ARGP), soccer players without ARGP and healthy volunteers from general population. Study included 36 male professional soccer players, who were randomly selected and followed-up over two years. Of the 21 soccer players eligible to participate in the study, 9 players went on to develop chronic ARGP and 12 players did not. Ten healthy male volunteers were randomly selected from the general population as a control group. Comparison between the abductor and adductor muscle peak torques for players with and without chronic ARGP found a statistically significant difference on the dominant and non-dominant sides (p < .005), with the abductor muscle significantly stronger than the adductor muscle. In the group of healthy volunteers, the adductor muscle groups were significantly stronger than the abductor muscle groups on both dominant and non-dominant sides (p < .05). For the group of players who had developed chronic ARGP, abductor-adductor torque ratios were significantly higher on the affected side (p = .008). The adductor muscle strength was also significantly decreased on the affected side. This imbalance appears to be a risk factor for adductor-related groin injury. Therefore, restoring the correct relationship between these two agonist and antagonist hip muscles may be an important preventative measure that should be a primary concern of training and rehabilitation programmes.
Public attitudes towards electroconvulsive therapy in the Chuvash Republic.
Golenkov, Andrei; Ungvari, Gabor S; Gazdag, Gábor
2012-05-01
Public attitudes towards a given medical procedure can have a significant influence on the employment of that method. Electroconvulsive therapy (ECT) is a medical procedure that has received an exceptionally ambiguous public reception since its inception. To survey the level of information about and attitudes towards ECT in a general population sample of the Chuvash Republic of the Russian Federation. A randomly selected cohort of 5,373 people was contacted by telephone. The respondents were asked three closed and three open questions. The response rate was 74.7%. Only 35.2% of those interviewed said they knew anything about ECT. Health professionals and younger respondents were better informed. The two main sources of information about ECT were foreign films and the mass media. The main indication of ECT was thought to be schizophrenia. The majority (63.3%) of the respondents had negative opinions and emotions about ECT. Limited information about and generally negative attitudes towards ECT were found in the general population of the Chuvash Republic. Gender, age, education level, employment in the health industry, and information source were found to be the determining factors in the knowledge of and attitudes towards ECT.
Global Existence Analysis of Cross-Diffusion Population Systems for Multiple Species
NASA Astrophysics Data System (ADS)
Chen, Xiuqing; Daus, Esther S.; Jüngel, Ansgar
2018-02-01
The existence of global-in-time weak solutions to reaction-cross-diffusion systems for an arbitrary number of competing population species is proved. The equations can be derived from an on-lattice random-walk model with general transition rates. In the case of linear transition rates, it extends the two-species population model of Shigesada, Kawasaki, and Teramoto. The equations are considered in a bounded domain with homogeneous Neumann boundary conditions. The existence proof is based on a refined entropy method and a new approximation scheme. Global existence follows under a detailed balance or weak cross-diffusion condition. The detailed balance condition is related to the symmetry of the mobility matrix, which mirrors Onsager's principle in thermodynamics. Under detailed balance (and without reaction) the entropy is nonincreasing in time, but counter-examples show that the entropy may increase initially if detailed balance does not hold.
Noise-induced effects in population dynamics
NASA Astrophysics Data System (ADS)
Spagnolo, Bernardo; Cirone, Markus; La Barbera, Antonino; de Pasquale, Ferdinando
2002-03-01
We investigate the role of noise in the nonlinear relaxation of two ecosystems described by generalized Lotka-Volterra equations in the presence of multiplicative noise. Specifically we study two cases: (i) an ecosystem with two interacting species in the presence of periodic driving; (ii) an ecosystem with a great number of interacting species with random interaction matrix. We analyse the interplay between noise and periodic modulation for case (i) and the role of the noise in the transient dynamics of the ecosystem in the presence of an absorbing barrier in case (ii). We find that the presence of noise is responsible for the generation of temporal oscillations and for the appearance of spatial patterns in the first case. In the other case we obtain the asymptotic behaviour of the time average of the ith population and discuss the effect of the noise on the probability distributions of the population and of the local field.
Uncertainty, learning, and the optimal management of wildlife
Williams, B.K.
2001-01-01
Wildlife management is limited by uncontrolled and often unrecognized environmental variation, by limited capabilities to observe and control animal populations, and by a lack of understanding about the biological processes driving population dynamics. In this paper I describe a comprehensive framework for management that includes multiple models and likelihood values to account for structural uncertainty, along with stochastic factors to account for environmental variation, random sampling, and partial controllability. Adaptive optimization is developed in terms of the optimal control of incompletely understood populations, with the expected value of perfect information measuring the potential for improving control through learning. The framework for optimal adaptive control is generalized by including partial observability and non-adaptive, sample-based updating of model likelihoods. Passive adaptive management is derived as a special case of constrained adaptive optimization, representing a potentially efficient suboptimal alternative that nonetheless accounts for structural uncertainty.
A systematic review of lifestyle counseling for diverse patients in primary care.
Melvin, Cathy L; Jefferson, Melanie S; Rice, LaShanta J; Nemeth, Lynne S; Wessell, Andrea M; Nietert, Paul J; Hughes-Halbert, Chanita
2017-07-01
Prior research and systematic reviews have examined strategies related to weight management, less is known about lifestyle and behavioral counseling interventions optimally suited for implementation in primary care practices generally, and among racial and ethnic patient populations. Primary care practitioners may find it difficult to access and use available research findings on effective behavioral and lifestyle counseling strategies and to assess their effects on health behaviors among their patients. This systematic review compiled existing evidence from randomized trials to inform primary care providers about which lifestyle and behavioral change interventions are shown to be effective for changing patients' diet, physical activity and weight outcomes. Searches identified 444 abstracts from all sources (01/01/2004-05/15/2014). Duplicate abstracts were removed, selection criteria applied and dual abstractions conducted for 106 full text articles. As of June 12, 2015, 29 articles were retained for inclusion in the body of evidence. Randomized trials tested heterogeneous multi-component behavioral interventions for an equally wide array of outcomes in three population groups: diverse patient populations (23 studies), African American patients only (4 studies), and Hispanic/Mexican American/Latino patients only (2 studies). Significant and consistent findings among diverse populations showed that weight and physical activity related outcomes were more amenable to change via lifestyle and behavioral counseling interventions than those associated with diet modification. Evidence to support specific interventions for racial and ethnic minorities was promising, but insufficient based on the small number of studies. Copyright © 2017. Published by Elsevier Inc.
Vallée, Julie; Souris, Marc; Fournet, Florence; Bochaton, Audrey; Mobillion, Virginie; Peyronnie, Karine; Salem, Gérard
2007-01-01
Background Geographical objectives and probabilistic methods are difficult to reconcile in a unique health survey. Probabilistic methods focus on individuals to provide estimates of a variable's prevalence with a certain precision, while geographical approaches emphasise the selection of specific areas to study interactions between spatial characteristics and health outcomes. A sample selected from a small number of specific areas creates statistical challenges: the observations are not independent at the local level, and this results in poor statistical validity at the global level. Therefore, it is difficult to construct a sample that is appropriate for both geographical and probability methods. Methods We used a two-stage selection procedure with a first non-random stage of selection of clusters. Instead of randomly selecting clusters, we deliberately chose a group of clusters, which as a whole would contain all the variation in health measures in the population. As there was no health information available before the survey, we selected a priori determinants that can influence the spatial homogeneity of the health characteristics. This method yields a distribution of variables in the sample that closely resembles that in the overall population, something that cannot be guaranteed with randomly-selected clusters, especially if the number of selected clusters is small. In this way, we were able to survey specific areas while minimising design effects and maximising statistical precision. Application We applied this strategy in a health survey carried out in Vientiane, Lao People's Democratic Republic. We selected well-known health determinants with unequal spatial distribution within the city: nationality and literacy. We deliberately selected a combination of clusters whose distribution of nationality and literacy is similar to the distribution in the general population. Conclusion This paper describes the conceptual reasoning behind the construction of the survey sample and shows that it can be advantageous to choose clusters using reasoned hypotheses, based on both probability and geographical approaches, in contrast to a conventional, random cluster selection strategy. PMID:17543100
Vallée, Julie; Souris, Marc; Fournet, Florence; Bochaton, Audrey; Mobillion, Virginie; Peyronnie, Karine; Salem, Gérard
2007-06-01
Geographical objectives and probabilistic methods are difficult to reconcile in a unique health survey. Probabilistic methods focus on individuals to provide estimates of a variable's prevalence with a certain precision, while geographical approaches emphasise the selection of specific areas to study interactions between spatial characteristics and health outcomes. A sample selected from a small number of specific areas creates statistical challenges: the observations are not independent at the local level, and this results in poor statistical validity at the global level. Therefore, it is difficult to construct a sample that is appropriate for both geographical and probability methods. We used a two-stage selection procedure with a first non-random stage of selection of clusters. Instead of randomly selecting clusters, we deliberately chose a group of clusters, which as a whole would contain all the variation in health measures in the population. As there was no health information available before the survey, we selected a priori determinants that can influence the spatial homogeneity of the health characteristics. This method yields a distribution of variables in the sample that closely resembles that in the overall population, something that cannot be guaranteed with randomly-selected clusters, especially if the number of selected clusters is small. In this way, we were able to survey specific areas while minimising design effects and maximising statistical precision. We applied this strategy in a health survey carried out in Vientiane, Lao People's Democratic Republic. We selected well-known health determinants with unequal spatial distribution within the city: nationality and literacy. We deliberately selected a combination of clusters whose distribution of nationality and literacy is similar to the distribution in the general population. This paper describes the conceptual reasoning behind the construction of the survey sample and shows that it can be advantageous to choose clusters using reasoned hypotheses, based on both probability and geographical approaches, in contrast to a conventional, random cluster selection strategy.
2014-01-01
Background Among glioma patients, depression is estimated to be more prevalent than in both the general population and the cancer patient population. This can have negative consequences for both patients and their primary informal caregivers (e.g., a spouse, family member or close friend). At present, there is no evidence from randomized controlled trials for the effectiveness of psychological treatment for depression in glioma patients. Furthermore, the possibility of delivering mental health care through the internet has not yet been explored in this population. Therefore, a randomized controlled trial is warranted to evaluate the effects of an internet-based, guided self-help intervention for depressive symptoms in glioma patients. Methods/design The intervention is based on problem-solving therapy. An existing 5-week course is adapted for use by adult glioma patients with mild to moderate depressive symptoms (Center for Epidemiology Studies Depression Scale score ≥12). Sample size calculations yield 126 glioma patients to be included, who are randomly assigned to either the intervention group or a waiting list control group. In addition, we aim to include 63 patients with haematological cancer in a non-central nervous system malignancy control group. Assessments take place at baseline, after 6 and 12 weeks, and after 6 and 12 months. Primary outcome measure is the change in depressive symptoms. Secondary outcome measures include health-related quality of life, fatigue, costs and patient satisfaction. In addition, all patients are asked to assign a primary informal caregiver, who does not participate in the intervention but who is asked to complete similar assessments. Their mood, health-related quality of life and fatigue is evaluated as well. Discussion This is the first study to evaluate the effects of problem-solving therapy delivered through the internet as treatment for depressive symptoms in glioma patients. If proven effective, this treatment will contribute to the mental health care of glioma patients in clinical practice. Trial registration Netherlands Trial Register NTR3223 PMID:24721108
de Quadros Onófrio, Fernanda; Lima, Julio Carlos Pereira; Watte, Guilherme; Lehmen, Romnei Lenon; Oba, Daniela; Camargo, Gabriela; Dos Santos, Carlos Eduardo Oliveira
2017-05-01
Background Acute pancreatitis is the most common complication after ERCP, occurring in about 4 % of the procedures. Only the placement of pancreatic duct prosthesis and the use of nonsteroidal anti-inflammatory drugs (NSAIDs) have shown benefit in the prevention of post-ERCP pancreatitis (PEP). Although the benefit of rectal administration of indomethacin or diclofenac is recommended by some studies and society guidelines especially in a selected group of high-risk patients, there is so far, no standardization of time or route of NSAID administration. The aim of the current study is to investigate the role of an intravenous NSAID administered before the procedure for PEP prevention. Methods In this randomized double-blind clinical trial, all consecutive patients who underwent ERCP were randomized to receive saline infusion with ketoprofen or saline, immediately before the procedure. Results A total of 477 patients were enrolled and completed follow-up. The majority of patients (72.1 %) had bile duct stones, and only 1.5 % had a clinical suspicion of sphincter of Oddi dysfunction. PEP developed in 5 of 253 (2 %) patients in the placebo group and in 5 of 224 (2.2 %) patients in the ketoprofen group (p = 1.). Conclusions Intravenous administration of ketoprofen immediately prior to ERCP did not result in reduction in PEP in a general population of ERCP patients.
Lo, Suzanne H S; Chang, Anne M; Chau, Janita P C
2018-03-01
Evidence shows self-management programs are associated with improved recovery outcomes. This article reports on the effectiveness of a new nurse-led self-efficacy-based stroke self-management program. A randomized controlled trial of participants recruited from 3 acute stroke units was conducted. The intervention group received the 4-week stroke self-management program. The control group received usual care. All participants were assessed at baseline and 8 weeks after randomization. Data were analyzed using generalized estimating equations. Outcomes included self-efficacy, outcome expectation, and satisfaction with performance of self-management behaviors. One hundred twenty-eight participants were randomized with mean age, 67.46 years (SD, 11.95); 59% men; and mean duration poststroke, 45 days (SD, 26.16). At 8 weeks of follow-up in the intention-to-treat population, the intervention group improved significantly in self-efficacy (95% confidence interval, 2.55-12.45; P <0.01), outcome expectation (95% confidence interval, 5.47-14.01; P <0.01), and satisfaction with performance of self-management behaviors (95% confidence interval, 3.38-13.87; P <0.01) compared with the control. Similar results were obtained at 8 weeks of follow-up in the per-protocol population. The stroke self-management program improved survivors' self-efficacy, outcome expectation, and satisfaction with performance of self-management behaviors. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02112955. © 2018 American Heart Association, Inc.
Clark, Christopher E; Taylor, Rod S; Shore, Angela C; Campbell, John L
2016-01-01
Background Various prevalence figures have been reported for inter-arm differences in blood pressure (IAD); variation may be explained by differing population vascular risk and by measurement method. Aim To review the literature to derive robust estimates of IAD prevalence relevant to community populations. Design and setting Systematic review and meta-analysis. Method MEDLINE, Embase, and CINAHL were searched for cross-sectional studies likely to represent general or primary care populations, reporting prevalence of IAD and employing a simultaneous method of measurement. Using study-level data, pooled estimates of mean prevalence of systolic IADs were calculated and compared using a random effects model. Results Eighty IAD studies were identified. Sixteen met inclusion criteria: pooled estimates of prevalence for systolic IAD ≥10 mmHg were 11.2% (95% confidence interval [CI] = 9.1 to 13.6) in hypertension, 7.4% (95% CI = 5.8 to 9.2) in diabetes, and 3.6% (95% CI = 2.3 to 5.0) for a general adult population (P<0.001 for subgroup differences). Differences persisted for higher cut-off values. Prevalences were lower for East Asian than for Western populations and were overestimated by sequential measurement where this could be compared with simultaneous measurement within studies (relative risk for IAD: 2.9 [95% CI = 2.1 to 4.1]). Studies with higher mean absolute systolic pressures had higher prevalences for a systolic IAD ≥10 mmHg (P = 0.04). Conclusion Prevalences of IADs rise in relation to underlying cardiovascular comorbidities of the population studied, and are overestimated threefold when sequential measurement is used. Population-specific variation in prevalences of IAD should be taken into account in delivering clinical care and in planning future studies. PMID:27789511
Fernandez-Mendoza, Julio; Calhoun, Susan L.; Bixler, Edward O.; Karataraki, Maria; Liao, Duanping; Vela-Bueno, Antonio; Ramos-Platon, María Jose; Sauder, Katherine A.; Basta, Maria; Vgontzas, Alexandros N.
2011-01-01
Objective Sleep misperception is considered by some investigators a common characteristic of chronic insomnia, whereas others propose it as a separate diagnosis. The frequency and the determinants of sleep misperception in general population samples are unknown. In this study we examined the role of objective sleep duration, a novel marker in phenotyping insomnia, and psychological profiles on sleep misperception in a large, general population sample. Methods 142 insomniacs and 724 controls selected from a general random sample of 1,741 individuals (age ≥ 20 years) underwent a polysomnographic evaluation, completed the Minnesota Multiphasic Personality Inventory-2, and were split into two groups based on their objective sleep duration: “normal sleep duration” (≥ 6 hours) and “short sleep duration” (< 6 hours). Results The discrepancy between subjective and objective sleep duration was determined by two independent factors. Short sleepers reported more sleep than they objectively had and insomniacs reported less sleep than controls with similar objective sleep duration. The additive effect of these two factors resulted in underestimation only in insomniacs with normal sleep duration. Insomniacs with normal sleep duration showed a MMPI-2 profile of high depression and anxiety, and low ego strength, whereas insomniacs with short sleep duration showed a profile of a medical disorder. Conclusions Underestimation of sleep duration is prevalent among insomniacs with objective normal sleep duration. Anxious-ruminative traits and poor resources for coping with stress appear to mediate the underestimation of sleep duration. These data further support the validity and clinical utility of objective sleep measures in phenotyping insomnia. PMID:20978224
Leptokurtic pollen-flow, non-leptokurtic gene-flow in a wind-pollinated herb, Plantago lanceolata L.
Tonsor, Stephen J
1985-10-01
The purpose of this study was to simultaneously measure pollen dispersal distance and actual pollen-mediated gene-flow distance in a wind-pollinated herb, Plantago lanceolata. The pollen dispersal distribution, measured as pollen deposition in a wind tunnel, is leptokurtic, as expected from previous studies of wind-pollinated plants. Gene-flow, measured as seeds produced on rows of male-sterile inflorescences in the wind tunnel, is non-leptokurtic, peaking at an intermediate distance. The difference between the two distributions results from the tendency of the pollen grains to cluster. These pollen clusters are the units of gene dispersal, with clusters of intermediate and large size contributing disproportionately to gene-flow. Since many wind-pollinated species show pollen clustering (see text), the common assumption for wind-pollinated plants that gene-flow is leptokurtic requires re-examination. Gene-flow was also measured in an artifical outdoor population of male-steriles, containing a single pollen source plant in the center of the array. The gene flow distribution is significantly platykurtic, and has the same general properties outdoors, where wind speed and turbulence are uncontrolled, as it does in the wind tunnel. I estimated genetic neighborhood size based on my measure of gene-flow in the outdoor population. The estimate shows that populations of Plantago lanceolata will vary in effective number from a few tens of plants to more than five hundred plants, depending on the density of the population in question. Thus, the measured pollen-mediated gene-flow distribution and population density will interact to produce effective population sizes ranging from those in which there is no random genetic drift to those in which random genetic drift plays an important role in determining gene frequencies within and among populations. Despite the platykurtosis in the distribution, pollen-mediated gene dispersal distances are still quite limited, and considerable within and among-population genetic differentiation is to be expected in this species.
Susceptible-infected-recovered epidemics in random networks with population awareness
NASA Astrophysics Data System (ADS)
Wu, Qingchu; Chen, Shufang
2017-10-01
The influence of epidemic information-based awareness on the spread of infectious diseases on networks cannot be ignored. Within the effective degree modeling framework, we discuss the susceptible-infected-recovered model in complex networks with general awareness and general degree distribution. By performing the linear stability analysis, the conditions of epidemic outbreak can be deduced and the results of the previous research can be further expanded. Results show that the local awareness can suppress significantly the epidemic spreading on complex networks via raising the epidemic threshold and such effects are closely related to the formulation of awareness functions. In addition, our results suggest that the recovered information-based awareness has no effect on the critical condition of epidemic outbreak.
47 CFR 1.1602 - Designation for random selection.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 1 2010-10-01 2010-10-01 false Designation for random selection. 1.1602 Section 1.1602 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Random Selection Procedures for Mass Media Services General Procedures § 1.1602 Designation for random selection...
47 CFR 1.1602 - Designation for random selection.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 1 2011-10-01 2011-10-01 false Designation for random selection. 1.1602 Section 1.1602 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Random Selection Procedures for Mass Media Services General Procedures § 1.1602 Designation for random selection...
Designing drug regimens for special intensive care unit populations
Erstad, Brian L
2015-01-01
This review is intended to help clinicians design drug regimens for special populations of critically ill patients with extremes of body size, habitus and composition that make drug choice or dosing particularly challenging due to the lack of high-level evidence on which to make well-informed clinical decisions. The data sources included a literature search of MEDLINE and EMBASE with reviews of reference lists of retrieved articles. Abstracts of original research investigations and review papers were reviewed for their relevance to drug choice or dosing in the following special critically ill populations: patients with more severe forms of bodyweight or height, patients with amputations or missing limbs, pregnant patients, and patients undergoing extracorporeal membrane oxygenation or plasma exchange. Relevant papers were retrieved and evaluated, and their associated reference lists were reviewed for citations that may have been missed through the electronic search strategy. Relevant original research investigations and review papers that could be used to formulate general principles for drug choice or dosing in special populations of critically ill patients were extracted. Randomized studies with clinically relevant endpoints were not available for performing quantitative analyses. Critically ill patients with changes in body size, habitus and composition require special consideration when designing medication regimens, but there is a paucity of literature on which to make drug-specific, high-level evidence-based recommendations. Based on the evidence that is available, general recommendations are provided for drug choice or dosing in special critically ill populations. PMID:25938029
Please don't misuse the museum: 'declines' may be statistical
Grant, Evan H. Campbell
2015-01-01
Detecting declines in populations at broad spatial scales takes enormous effort, and long-term data are often more sparse than is desired for estimating trends, identifying drivers for population changes, framing conservation decisions or taking management actions. Museum records and historic data can be available at large scales across multiple decades, and are therefore an attractive source of information on the comparative status of populations. However, changes in populations may be real (e.g., in response to environmental covariates) or resulting from variation in our ability to observe the true population response (also possibly related to environmental covariates). This is a (statistical) nuisance in understanding the true status of a population. Evaluating statistical hypotheses alongside more interesting ecological ones is important in the appropriate use of museum data. Two statistical considerations are generally applicable to use of museum records: first without initial random sampling, comparison with contemporary results cannot provide inference to the entire range of a species, and second the availability of only some individuals in a population may respond to environmental changes. Changes in the availability of individuals may reduce the proportion of the population that is present and able to be counted on a given survey event, resulting in an apparent decline even when population size is stable.
Rosenberg, Noah A; Mahajan, Saurabh; Gonzalez-Quevedo, Catalina; Blum, Michael G B; Nino-Rosales, Laura; Ninis, Vasiliki; Das, Parimal; Hegde, Madhuri; Molinari, Laura; Zapata, Gladys; Weber, James L; Belmont, John W; Patel, Pragna I
2006-12-01
Ongoing modernization in India has elevated the prevalence of many complex genetic diseases associated with a western lifestyle and diet to near-epidemic proportions. However, although India comprises more than one sixth of the world's human population, it has largely been omitted from genomic surveys that provide the backdrop for association studies of genetic disease. Here, by genotyping India-born individuals sampled in the United States, we carry out an extensive study of Indian genetic variation. We analyze 1,200 genome-wide polymorphisms in 432 individuals from 15 Indian populations. We find that populations from India, and populations from South Asia more generally, constitute one of the major human subgroups with increased similarity of genetic ancestry. However, only a relatively small amount of genetic differentiation exists among the Indian populations. Although caution is warranted due to the fact that United States-sampled Indian populations do not represent a random sample from India, these results suggest that the frequencies of many genetic variants are distinctive in India compared to other parts of the world and that the effects of population heterogeneity on the production of false positives in association studies may be smaller in Indians (and particularly in Indian-Americans) than might be expected for such a geographically and linguistically diverse subset of the human population.
Kamishiraki, Etsuko; Maeda, Shoichi; Starkey, Jay; Ikeda, Noriaki
2012-12-01
Autopsy is a useful tool for understanding the cause and manner of unexpected patient death. However, the attitudes of the general public and physicians in Japan about clinical autopsy are limited. To describe the beliefs of the general public about whether autopsy should be performed and ascertain if they would actually request one given specific clinical situations where patient death occurred with the additional variable of medical error. To compare these attitudes with previously obtained attitudes of physicians practising at Japanese teaching hospitals. We conducted a cross-sectional study of the general public. We sent standardised questionnaires in 2010 to a randomly selected non-physician adult population using a survey company for participant selection. Respondents gave their opinions about the necessity of autopsy and how they might act given various clinical scenarios of patient death. We compared these results with those of a previous survey of Japanese physicians conducted in 2009. Of the 2300 eligible general adult population, 1575 (68.5%) responded. The majority of the general public indicated they believed an autopsy was necessary. However, in cases of unclear medical error or unclear cause and effect relationship of medical care and patient death, the general public were much less likely to indicate they would actually request an autopsy than were physicians (p<0.0001). Currently in Japan the debate about the role autopsy should play in the case of error related to death is underway. The results from this study will be important in informing related decisions.
Prospects for Genomic Selection in Cassava Breeding.
Wolfe, Marnin D; Del Carpio, Dunia Pino; Alabi, Olumide; Ezenwaka, Lydia C; Ikeogu, Ugochukwu N; Kayondo, Ismail S; Lozano, Roberto; Okeke, Uche G; Ozimati, Alfred A; Williams, Esuma; Egesi, Chiedozie; Kawuki, Robert S; Kulakow, Peter; Rabbi, Ismail Y; Jannink, Jean-Luc
2017-11-01
Cassava ( Crantz) is a clonally propagated staple food crop in the tropics. Genomic selection (GS) has been implemented at three breeding institutions in Africa to reduce cycle times. Initial studies provided promising estimates of predictive abilities. Here, we expand on previous analyses by assessing the accuracy of seven prediction models for seven traits in three prediction scenarios: cross-validation within populations, cross-population prediction and cross-generation prediction. We also evaluated the impact of increasing the training population (TP) size by phenotyping progenies selected either at random or with a genetic algorithm. Cross-validation results were mostly consistent across programs, with nonadditive models predicting of 10% better on average. Cross-population accuracy was generally low (mean = 0.18) but prediction of cassava mosaic disease increased up to 57% in one Nigerian population when data from another related population were combined. Accuracy across generations was poorer than within-generation accuracy, as expected, but accuracy for dry matter content and mosaic disease severity should be sufficient for rapid-cycling GS. Selection of a prediction model made some difference across generations, but increasing TP size was more important. With a genetic algorithm, selection of one-third of progeny could achieve an accuracy equivalent to phenotyping all progeny. We are in the early stages of GS for this crop but the results are promising for some traits. General guidelines that are emerging are that TPs need to continue to grow but phenotyping can be done on a cleverly selected subset of individuals, reducing the overall phenotyping burden. Copyright © 2017 Crop Science Society of America.
Stewart, Catherine; Kopinski, Hannah; Liebschutz, Jane; Holmdahl, Inga; Keosaian, Julia; Herman, Debra; Anderson, Bradley; Stein, Michael
2018-03-01
Studies of drug-using populations often restrict enrollment by limiting participation to those with a working telephone. It is unknown whether supplying phones could broaden recruitment and sustain retention among an urban population of people who inject drugs (PWID). We compare the feasibility of offering pay-by-month phones to gift card compensation as part of an ongoing randomized controlled trial of hospitalized PWID. Participants were recruited from inpatient services at an urban hospital in Boston, MA to participate in an ongoing randomized trial testing a motivational interviewing (MI) intervention. Participants who did not have their own phone at the time of enrollment were offered a pay-by-month phones as compensation for study participation. Eighty-one participants met study criteria, were enrolled, and completed the study at the time of analysis. We used a generalized estimating equation to compare the overall likelihood of attending interviews during the 12-month follow-up period. Participants receiving phones tended to have lower mean educational attainment (11.4 years vs. 12.1 years), were significantly (Fisher's exact p < 0.001) more likely to report homelessness during the past 90 days (86.7% vs. 37.3%), and were significantly less likely (Fisher's exact p = .044) to be employed (3.3% vs. 20.4%) compared to those receiving gift cards. Participants in each group were equally likely to attend follow-up interviews during the study (83.3% vs. 88.3%, p = 0.53). Offering phones as a compensation method allows recruitment of a more disenfranchised population without impacting study retention and therefore may improve generalizability of study results. Copyright © 2018 Elsevier B.V. All rights reserved.
McElfish, Pearl Anna; Long, Christopher R; Kaholokula, Joseph Keawe'aimoku; Aitaoto, Nia; Bursac, Zoran; Capelle, Lucy; Laelan, Melisa; Bing, Williamina Ioanna; Riklon, Sheldon; Rowland, Brett; Ayers, Britni L; Wilmoth, Ralph O; Langston, Krista N; Schootman, Mario; Selig, James P; Yeary, Karen Hye-Cheon Kim
2018-05-01
Pacific Islander populations, including Marshallese, face a disproportionately high burden of health disparities relative to the general population. A community-based participatory research (CBPR) approach was utilized to engage Marshallese participants in a comparative effectiveness trial testing 2 Diabetes Prevention Program (DPP) interventions designed to reduce participant's weight, lower HbA1c, encourage healthy eating, and increase physical activity. To compare the effectiveness of the faith-based (WORD) DPP to the culturally adapted (Pacific Culturally Adapted Diabetes Prevention Program [PILI]) DPP, a clustered randomized controlled trial (RCT) with 384 Marshallese participants will be implemented in 32 churches located in Arkansas, Kansas, Missouri, and Oklahoma. Churches will be randomly assigned to WORD DPP arm or to PILI DPP arm. WORD DPP focuses on connecting faith and health to attain a healthy weight, eat healthy, and be more physically active. In contrast, PILI DPP is a family and community focused DPP curriculum specifically adapted for implementation in Pacific Islander communities. PILI focuses on engaging social support networks to maintain a healthy weight, eat healthy, and be more physically active. All participants are assessed at baseline, immediate post intervention, and 12 months post intervention. Both interventions aim to cause weight loss through improving physical activity and healthy eating, with the goal of preventing the development of T2D. The clustered RCT will determine which intervention is most effective with the Marshallese population. The utilization of a CBPR approach that involves local stakeholders and engages faith-based institutions in Marshallese communities will increase the potential for success and sustainability. This study is registered at clinicaltrials.gov (NCT03270436).
McElfish, Pearl Anna; Long, Christopher R.; Kaholokula, Joseph Keawe‘aimoku; Aitaoto, Nia; Bursac, Zoran; Capelle, Lucy; Laelan, Melisa; Bing, Williamina Ioanna; Riklon, Sheldon; Rowland, Brett; Ayers, Britni L.; Wilmoth, Ralph O.; Langston, Krista N.; Schootman, Mario; Selig, James P.; Yeary, Karen Hye-cheon Kim
2018-01-01
Abstract Background: Pacific Islander populations, including Marshallese, face a disproportionately high burden of health disparities relative to the general population. Objectives: A community-based participatory research (CBPR) approach was utilized to engage Marshallese participants in a comparative effectiveness trial testing 2 Diabetes Prevention Program (DPP) interventions designed to reduce participant's weight, lower HbA1c, encourage healthy eating, and increase physical activity. Design: To compare the effectiveness of the faith-based (WORD) DPP to the culturally adapted (Pacific Culturally Adapted Diabetes Prevention Program [PILI]) DPP, a clustered randomized controlled trial (RCT) with 384 Marshallese participants will be implemented in 32 churches located in Arkansas, Kansas, Missouri, and Oklahoma. Churches will be randomly assigned to WORD DPP arm or to PILI DPP arm. Methods: WORD DPP focuses on connecting faith and health to attain a healthy weight, eat healthy, and be more physically active. In contrast, PILI DPP is a family and community focused DPP curriculum specifically adapted for implementation in Pacific Islander communities. PILI focuses on engaging social support networks to maintain a healthy weight, eat healthy, and be more physically active. All participants are assessed at baseline, immediate post intervention, and 12 months post intervention. Summary: Both interventions aim to cause weight loss through improving physical activity and healthy eating, with the goal of preventing the development of T2D. The clustered RCT will determine which intervention is most effective with the Marshallese population. The utilization of a CBPR approach that involves local stakeholders and engages faith-based institutions in Marshallese communities will increase the potential for success and sustainability. This study is registered at clinicaltrials.gov (NCT03270436). PMID:29742712
Social Network Sensors for Early Detection of Contagious Outbreaks
Christakis, Nicholas A.; Fowler, James H.
2010-01-01
Current methods for the detection of contagious outbreaks give contemporaneous information about the course of an epidemic at best. It is known that individuals near the center of a social network are likely to be infected sooner during the course of an outbreak, on average, than those at the periphery. Unfortunately, mapping a whole network to identify central individuals who might be monitored for infection is typically very difficult. We propose an alternative strategy that does not require ascertainment of global network structure, namely, simply monitoring the friends of randomly selected individuals. Such individuals are known to be more central. To evaluate whether such a friend group could indeed provide early detection, we studied a flu outbreak at Harvard College in late 2009. We followed 744 students who were either members of a group of randomly chosen individuals or a group of their friends. Based on clinical diagnoses, the progression of the epidemic in the friend group occurred 13.9 days (95% C.I. 9.9–16.6) in advance of the randomly chosen group (i.e., the population as a whole). The friend group also showed a significant lead time (p<0.05) on day 16 of the epidemic, a full 46 days before the peak in daily incidence in the population as a whole. This sensor method could provide significant additional time to react to epidemics in small or large populations under surveillance. The amount of lead time will depend on features of the outbreak and the network at hand. The method could in principle be generalized to other biological, psychological, informational, or behavioral contagions that spread in networks. PMID:20856792
47 CFR 1.1603 - Conduct of random selection.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 1 2010-10-01 2010-10-01 false Conduct of random selection. 1.1603 Section 1.1603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Random Selection Procedures for Mass Media Services General Procedures § 1.1603 Conduct of random selection. The...
47 CFR 1.1603 - Conduct of random selection.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 1 2011-10-01 2011-10-01 false Conduct of random selection. 1.1603 Section 1.1603 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Random Selection Procedures for Mass Media Services General Procedures § 1.1603 Conduct of random selection. The...
Munhoz, R E F; Prioli, A J; Amaral, A T; Scapim, C A; Simon, G A
2009-08-11
Diallel analysis was used to obtain information on combining ability, heterosis, estimates of genetic distances by random amplified polymorphic DNA (RAPD) and on their correlations with heterosis, for the popcorn varieties RS 20, UNB2, CMS 43, CMS 42, Zélia, UEM J1, UEM M2, Beija-Flor, and Viçosa, which were crossed to obtain all possible combinations, without reciprocals. The genitors and the 36 F(1) hybrids were evaluated in field trials in Maringá during two growing seasons in a randomized complete block design with three replications. Based on the results, strategies for further studies were developed, including the construction of composites by joining varieties with high general combining ability for grain yield (UNB2 and CMS 42) with those with high general combining ability for popping expansion (Zélia, RS 20 and UEM M2). Based on the RAPD markers, UEM J1 and Zélia were the most genetically distant and RS 20 and UNB2 were the most similar. The low correlation between heterosis and genetic distances may be explained by the random dispersion of the RAPD markers, which were insufficient for the exploitation of the popcorn genome. We concluded that an association between genetic dissimilarity and heterosis based only on genetic distance is not expected without considering the effect of dominant loci.
Sindi, Shireen; Ngandu, Tiia; Hovatta, Iiris; Kåreholt, Ingemar; Antikainen, Riitta; Hänninen, Tuomo; Levälahti, Esko; Laatikainen, Tiina; Lindström, Jaana; Paajanen, Teemu; Peltonen, Markku; Khalsa, Dharma Singh; Wolozin, Benjamin; Strandberg, Timo; Tuomilehto, Jaakko; Soininen, Hilkka; Kivipelto, Miia; Solomon, Alina
2017-01-01
Leukocyte telomere length (LTL) is a biomarker of aging, and it is associated with lifestyle. It is currently unknown whether LTL is associated with the response to lifestyle interventions. The goal is to assess whether baseline LTL modified the cognitive benefits of a 2-year multidomain lifestyle intervention (exploratory analyses). The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) was a 2-year randomized controlled trial including 1,260 people at risk of cognitive decline, aged 60–77 years identified from the general population. Participants were randomly assigned to the lifestyle intervention (diet, exercise, cognitive training, and vascular risk management) and control (general health advice) groups. Primary outcome was change in cognition (comprehensive neuropsychological test battery). Secondary outcomes were changes in cognitive domains: memory, executive functioning, and processing speed. 775 participants (392 control, 383 intervention) had baseline LTL (peripheral blood DNA). Mixed effects regression models with maximum likelihood estimation were used to analyze change in cognition as a function of randomization group, time, baseline LTL, and their interaction. Intervention and control groups did not significantly differ at baseline. Shorter LTL was related to less healthy baseline lifestyle. Intervention benefits on executive functioning were more pronounced among those with shorter baseline LTL (p-value for interaction was 0.010 adjusted for age and sex, and 0.007 additionally adjusted for baseline lifestyle factors). The FINGER intervention cognitive benefits were more pronounced with shorter baseline LTL, particularly for executive functioning, indicating that the multidomain lifestyle intervention was especially beneficial among higher-risk individuals. PMID:28777749
Kashdan, Todd B; Farmer, Antonina S
2014-06-01
The ability to recognize and label emotional experiences has been associated with well-being and adaptive functioning. This skill is particularly important in social situations, as emotions provide information about the state of relationships and help guide interpersonal decisions, such as whether to disclose personal information. Given the interpersonal difficulties linked to social anxiety disorder (SAD), deficient negative emotion differentiation may contribute to impairment in this population. We hypothesized that people with SAD would exhibit less negative emotion differentiation in daily life, and these differences would translate to impairment in social functioning. We recruited 43 people diagnosed with generalized SAD and 43 healthy adults to describe the emotions they experienced over 14 days. Participants received palmtop computers for responding to random prompts and describing naturalistic social interactions; to complete end-of-day diary entries, they used a secure online website. We calculated intraclass correlation coefficients to capture the degree of differentiation of negative and positive emotions for each context (random moments, face-to-face social interactions, and end-of-day reflections). Compared to healthy controls, the SAD group exhibited less negative (but not positive) emotion differentiation during random prompts, social interactions, and (at trend level) end-of-day assessments. These differences could not be explained by emotion intensity or variability over the 14 days, or to comorbid depression or anxiety disorders. Our findings suggest that people with generalized SAD have deficits in clarifying specific negative emotions felt at a given point of time. These deficits may contribute to difficulties with effective emotion regulation and healthy social relationship functioning.
Sindi, Shireen; Ngandu, Tiia; Hovatta, Iiris; Kåreholt, Ingemar; Antikainen, Riitta; Hänninen, Tuomo; Levälahti, Esko; Laatikainen, Tiina; Lindström, Jaana; Paajanen, Teemu; Peltonen, Markku; Khalsa, Dharma Singh; Wolozin, Benjamin; Strandberg, Timo; Tuomilehto, Jaakko; Soininen, Hilkka; Kivipelto, Miia; Solomon, Alina
2017-01-01
Leukocyte telomere length (LTL) is a biomarker of aging, and it is associated with lifestyle. It is currently unknown whether LTL is associated with the response to lifestyle interventions. The goal is to assess whether baseline LTL modified the cognitive benefits of a 2-year multidomain lifestyle intervention (exploratory analyses). The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) was a 2-year randomized controlled trial including 1,260 people at risk of cognitive decline, aged 60-77 years identified from the general population. Participants were randomly assigned to the lifestyle intervention (diet, exercise, cognitive training, and vascular risk management) and control (general health advice) groups. Primary outcome was change in cognition (comprehensive neuropsychological test battery). Secondary outcomes were changes in cognitive domains: memory, executive functioning, and processing speed. 775 participants (392 control, 383 intervention) had baseline LTL (peripheral blood DNA). Mixed effects regression models with maximum likelihood estimation were used to analyze change in cognition as a function of randomization group, time, baseline LTL, and their interaction. Intervention and control groups did not significantly differ at baseline. Shorter LTL was related to less healthy baseline lifestyle. Intervention benefits on executive functioning were more pronounced among those with shorter baseline LTL (p-value for interaction was 0.010 adjusted for age and sex, and 0.007 additionally adjusted for baseline lifestyle factors). The FINGER intervention cognitive benefits were more pronounced with shorter baseline LTL, particularly for executive functioning, indicating that the multidomain lifestyle intervention was especially beneficial among higher-risk individuals.
What influences participation in genetic carrier testing? Results from a discrete choice experiment.
Hall, Jane; Fiebig, Denzil G; King, Madeleine T; Hossain, Ishrat; Louviere, Jordan J
2006-05-01
This study explores factors that influence participation in genetic testing programs and the acceptance of multiple tests. Tay Sachs and cystic fibrosis are both genetically determined recessive disorders with differing severity, treatment availability, and prevalence in different population groups. We used a discrete choice experiment with a general community and an Ashkenazi Jewish sample; data were analysed using multinomial logit with random coefficients. Although Jewish respondents were more likely to be tested, both groups seem to be making very similar tradeoffs across attributes when they make genetic testing choices.
New Options in Constipation Management.
Davis, Mellar; Gamier, Pamela
2015-12-01
Constipation is common in the general population and for those on opioids and/or who are suffering from advanced cancer. Self-management consists of dietary changes, exercise, and laxatives. However, responses to self-management efforts are often inadequate to relieve the subjective and objective experience of constipation. Multiple new anti-constipating medications have recently been tested in randomized trials and the following are available commercially: probiotics, prucalopride, lubiprostone, linaclotide, elobixibat, antidepressants, methylnaltrexone, alvimopan, and naloxegol. This review will discuss the evidence-based benefits of these medications and outline an approach to managing constipation.
ON THE TIDAL DISSIPATION OF OBLIQUITY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rogers, T. M.; Lin, D. N. C., E-mail: tami@lpl.arizona.edu, E-mail: lin@ucolick.org
2013-05-20
We investigate tidal dissipation of obliquity in hot Jupiters. Assuming an initial random orientation of obliquity and parameters relevant to the observed population, the obliquity of hot Jupiters does not evolve to purely aligned systems. In fact, the obliquity evolves to either prograde, retrograde, or 90 Degree-Sign orbits where the torque due to tidal perturbations vanishes. This distribution is incompatible with observations which show that hot Jupiters around cool stars are generally aligned. This calls into question the viability of tidal dissipation as the mechanism for obliquity alignment of hot Jupiters around cool stars.
2014-08-01
the Minister of National Defence, 2014 © Sa Majesté la Reine (en droit du Canada), telle que représentée par le ministre de la Défense nationale...specifically for the target GRCT population. The internal consistency and factorial validity of this new measure has been established in a series of studies...measure. Journal of general internal medicine. 2001;16(9):606-13. [11] Richards K, Fikretoglu D. Using Administrative Data to Inform the Design of a
Nightmares: Risk Factors Among the Finnish General Adult Population
Sandman, Nils; Valli, Katja; Kronholm, Erkki; Revonsuo, Antti; Laatikainen, Tiina; Paunio, Tiina
2015-01-01
Study Objectives: To identify risk factors for experiencing nightmares among the Finnish general adult population. The study aimed to both test whether previously reported correlates of frequent nightmares could be reproduced in a large population sample and to explore previously unreported associations. Design: Two independent cross-sectional population surveys of the National FINRISK Study. Setting: Age- and sex-stratified random samples of the Finnish population in 2007 and 2012. Participants: A total of 13,922 participants (6,515 men and 7,407 women) aged 25–74 y. Interventions: N/A. Measurements and results: Nightmare frequency as well as several items related to socioeconomic status, sleep, mental well-being, life satisfaction, alcohol use, medication, and physical well-being were recorded with a questionnaire. In multinomial logistic regression analysis, a depression-related negative attitude toward the self (odds ratio [OR] 1.32 per 1-point increase), insomnia (OR 6.90), and exhaustion and fatigue (OR 6.86) were the strongest risk factors for experiencing frequent nightmares (P < 0.001 for all). Sex, age, a self-reported impaired ability to work, low life satisfaction, the use of antidepressants or hypnotics, and frequent heavy use of alcohol were also strongly associated with frequent nightmares (P < 0.001 for all). Conclusions: Symptoms of depression and insomnia were the strongest predictors of frequent nightmares in this dataset. Additionally, a wide variety of factors related to psychological and physical well-being were associated with nightmare frequency with modest effect sizes. Hence, nightmare frequency appears to have a strong connection with sleep and mood problems, but is also associated with a variety of measures of psychological and physical well-being. Citation: Sandman N, Valli K, Kronholm E, Revonsuo A, Laatikainen T, Paunio T. Nightmares: risk factors among the finnish general adult population. SLEEP 2015;38(4):507–514. PMID:25325474
Serum γ-glutamyltransferase and associated damage among a She Chinese population.
Lin, Y; Xu, Y; Chen, G; Huang, B; Yao, J; Chen, Z; Yao, L; Lin, F; Qiao, Y; Chen, Z; Zhu, S; Huang, H; Wen, J
2011-08-01
It has been suggested that serum γ-glutamyltransferase is independently associated with cardiovascular mortality and atherosclerosis. The present study is to investigate the relationship between serum γ-glutamyltransferase and potential associated damage in an adult She Chinese population. A multistage, stratified, cluster, random sampling method was used to select an ethnically representative group of individuals aged 20-80 years in the general population. Brachial-ankle pulse-wave velocity was used to assess arterial stiffness in the general population and the Toronto Clinical Neuropathy Scoring System was used to detect diabetic peripheral polyneuropathy among populations with diabetes. A total of 5385 subjects were entered into the analysis. Serum γ-glutamyltransferase levels were classified into four groups using the 25th, 50th and 75th percentiles as cut points (males: < 20, 20-29, 29-52 and > 52 U/l; females: < 13, 13-18, 18-25 and > 25 U/l). As compared with the first quartile, the relative risks of arterial stiffness were 1.418, 1.667 and 2.394 in the other three categories, respectively (test for trend P < 0.05). After adjustment in five models, serum γ-glutamyltransferase was still a risk factor of arterial stiffness. We found inverted U-shape curves in both genders and the third quartile (male: 29 52 U/l; female: 18-25 U/l) had the highest odds ratios of 1.640 and 1.529, respectively. We demonstrated that high serum γ-glutamyltransferase concentrations were directly associated with the increased risk of arterial stiffness, in general, and with peripheral polyneuropathy in subjects with diabetes in an ethnic She Chinese population. Alcohol use, gender, BMI and blood pressure were related to serum γ-glutamyltransferase and were involved in the relationship between serum γ-glutamyltransferase and brachial-ankle pulse-wave velocity. © 2011 The Authors. Diabetic Medicine © 2011 Diabetes UK.
Back pain in a large Canadian police force.
Brown, J J; Wells, G A; Trottier, A J; Bonneau, J; Ferris, B
1998-04-01
A survey of a random sample of 1002 members of the Royal Canadian Mounted Police to determine their experience with low back pain. To determine the prevalence of low back pain among Royal Canadian Mounted Police members and to assess the validity of the perception that the patrol car seat and the duty belt are causing a higher rate of low back pain among members of the Royal Canadian Mounted Police than in the general population. Low back pain is a common problem throughout the industrialized world, with reported 1-year prevalence rates between 25% and 62%. Prevalence of low back pain among people who drive motor vehicles for a significant part of the day appears higher than in the general population. Among police officers, 1-year prevalence rates of between 44% and 62% have been reported. A computerized database of 14,897 serving regular members was used to identify a sample of officers on active duty. A low back pain questionnaire was mailed to each selected member, eliciting information regarding their experience with low back pain, their exposure to known and putative risk factors, and their opinions about the contribution of these potential risk factors. The respondents to the questionnaire remained anonymous. The response rate was 80%. The prevalence of "chronic or recurring low back pain since joining the force" was 54.9%, which is comparable with the lifetime prevalence reported for the general population. Of those who reported having back problems, only 8.5% had such problems before joining the force. Seventy-six percent who had low back pain reported having a problem within the last year, giving an overall 1-year prevalence of 41.8%, which is comparable with that for the general population. The a priori assumption that driving or wearing a duty belt contributed to the problem was shared by most police officers surveyed. However, only about half of the members who replied drove for more than half the working day or wore the duty belt. These members had the same prevalence of low back pain as those who did not drive or wear the duty belt. The prevalence of low back pain in this police force is comparable with that in the general population, and driving a patrol car or wearing the duty belt does not appear to influence the prevalence rate in this population.
Gravity and the orientation of cell division
NASA Technical Reports Server (NTRS)
Helmstetter, C. E.
1997-01-01
A novel culture system for mammalian cells was used to investigate division orientations in populations of Chinese hamster ovary cells and the influence of gravity on the positioning of division axes. The cells were tethered to adhesive sites, smaller in diameter than a newborn cell, distributed over a nonadhesive substrate positioned vertically. The cells grew and divided while attached to the sites, and the angles and directions of elongation during anaphase, projected in the vertical plane, were found to be random with respect to gravity. However, consecutive divisions of individual cells were generally along the same axis or at 90 degrees to the previous division, with equal probability. Thus, successive divisions were restricted to orthogonal planes, but the choice of plane appeared to be random, unlike the ordered sequence of cleavage orientations seen during early embryo development.
Clinical Perspectives of Genetic Analyses on Dyslipidemia and Coronary Artery Disease
Kawashiri, Masa-aki; Yamagishi, Masakazu
2017-01-01
We have learned that low-density lipoprotein (LDL) cholesterol is the cause of atherosclerosis from various aspects, including a single case with familial hypercholesterolemia, other cases with different types of Mendelian dyslipidemias, large-scale randomized controlled trials using LDL cholesterol lowering therapies, and Mendelian randomization studies using common as well as rare variants associated with LDL cholesterol levels. There is no doubt that determinations of genotypes in lipid-associated genes have contributed not only to the genetic diagnosis for Mendelian dyslipidemias but also to the discoveries of novel therapeutic targets. Furthermore, recent studies have shown that such genetic information could provide useful clues for the risk prediction as well as risk stratification in general and in particular population. We provide the current understanding of genetic analyses relating to plasma lipids and coronary artery disease. PMID:28250266
A Community-Based Randomized Trial of Hepatitis B Screening Among High-Risk Vietnamese Americans.
Ma, Grace X; Fang, Carolyn Y; Seals, Brenda; Feng, Ziding; Tan, Yin; Siu, Philip; Yeh, Ming Chin; Golub, Sarit A; Nguyen, Minhhuyen T; Tran, Tam; Wang, Minqi
2017-03-01
To evaluate the effectiveness of a community-based liver cancer prevention program on hepatitis B virus (HBV) screening among low-income, underserved Vietnamese Americans at high risk. We conducted a cluster randomized trial involving 36 Vietnamese community-based organizations and 2337 participants in Pennsylvania, New Jersey, and New York City between 2009 and 2014. We randomly assigned 18 community-based organizations to a community-based multilevel HBV screening intervention (n = 1131). We randomly assigned the remaining 18 community-based organizations to a general cancer education program (n = 1206), which included information about HBV-related liver cancer prevention. We assessed HBV screening rates at 6-month follow-up. Intervention participants were significantly more likely to have undergone HBV screening (88.1%) than were control group participants (4.6%). In a Cochran-Mantel-Haenszel analysis, the intervention effect on screening outcomes remained statistically significant after adjustment for demographic and health care access variables, including income, having health insurance, having a regular health provider, and English proficiency. A community-based, culturally appropriate, multilevel HBV screening intervention effectively increases screening rates in a high-risk, hard-to-reach Vietnamese American population.
Lotka-Volterra systems in environments with randomly disordered temporal periodicity
NASA Astrophysics Data System (ADS)
Naess, Arvid; Dimentberg, Michael F.; Gaidai, Oleg
2008-08-01
A generalized Lotka-Volterra model for a pair of interacting populations of predators and prey is studied. The model accounts for the prey’s interspecies competition and therefore is asymptotically stable, whereas its oscillatory behavior is induced by temporal variations in environmental conditions simulated by those in the prey’s reproduction rate. Two models of the variations are considered, each of them combining randomness with “hidden” periodicity. The stationary joint probability density function (PDF) of the number of predators and prey is calculated numerically by the path integration (PI) method based on the use of characteristic functions and the fast Fourier transform. The numerical results match those for the asymptotic case of white-noise variations for which an analytical solution is available. Several examples are studied, with calculations of important characteristics of oscillations, for example the expected rate of up-crossings given the level of the predator number. The calculated PDFs may be of predominantly random (unimodal) or predominantly periodic nature (bimodal). Thus, the PI method has been demonstrated to be a powerful tool for studies of the dynamics of predator-prey pairs. The method captures the random oscillations as observed in nature, taking into account potential periodicity in the environmental conditions.
Lotka-Volterra systems in environments with randomly disordered temporal periodicity.
Naess, Arvid; Dimentberg, Michael F; Gaidai, Oleg
2008-08-01
A generalized Lotka-Volterra model for a pair of interacting populations of predators and prey is studied. The model accounts for the prey's interspecies competition and therefore is asymptotically stable, whereas its oscillatory behavior is induced by temporal variations in environmental conditions simulated by those in the prey's reproduction rate. Two models of the variations are considered, each of them combining randomness with "hidden" periodicity. The stationary joint probability density function (PDF) of the number of predators and prey is calculated numerically by the path integration (PI) method based on the use of characteristic functions and the fast Fourier transform. The numerical results match those for the asymptotic case of white-noise variations for which an analytical solution is available. Several examples are studied, with calculations of important characteristics of oscillations, for example the expected rate of up-crossings given the level of the predator number. The calculated PDFs may be of predominantly random (unimodal) or predominantly periodic nature (bimodal). Thus, the PI method has been demonstrated to be a powerful tool for studies of the dynamics of predator-prey pairs. The method captures the random oscillations as observed in nature, taking into account potential periodicity in the environmental conditions.
A Portuguese value set for the SF-6D.
Ferreira, Lara N; Ferreira, Pedro L; Pereira, Luis N; Brazier, John; Rowen, Donna
2010-08-01
The SF-6D is a preference-based measure of health derived from the SF-36 that can be used for cost-effectiveness analysis using cost-per-quality adjusted life-year analysis. This study seeks to estimate a system weight for the SF-6D for Portugal and to compare the results with the UK system weights. A sample of 55 health states defined by the SF-6D has been valued by a representative random sample of the Portuguese population, stratified by sex and age (n = 140), using the Standard Gamble (SG). Several models are estimated at both the individual and aggregate levels for predicting health-state valuations. Models with main effects, with interaction effects and with the constant forced to unity are presented. Random effects (RE) models are estimated using generalized least squares (GLS) regressions. Generalized estimation equations (GEE) are used to estimate RE models with the constant forced to unity. Estimations at the individual level were performed using 630 health-state valuations. Alternative functional forms are considered to account for the skewed distribution of health-state valuations. The models are analyzed in terms of their coefficients, overall fit, and the ability for predicting the SG-values. The RE models estimated using GLS and through GEE produce significant coefficients, which are robust across model specification. However, there are concerns regarding some inconsistent estimates, and so parsimonious consistent models were estimated. There is evidence of under prediction in some states assigned to poor health. The results are consistent with the UK results. The models estimated provide preference-based quality of life weights for the Portuguese population when health status data have been collected using the SF-36. Although the sample was randomly drowned findings should be treated with caution, given the small sample size, even knowing that they have been estimated at the individual level.
Sofi, Francesco; Dinu, Monica; Pagliai, Giuditta; Cesari, Francesca; Marcucci, Rossella; Casini, Alessandro
2016-05-04
Nutrition is able to alter the cardiovascular health of the general population. However, the optimal dietary strategy for cardiovascular disease prevention is still far from being defined. Mediterranean and vegetarian diets are those reporting the greatest grade of evidence in the literature, but no experimental studies comparing these two dietary patterns are available. This is an open randomized crossover clinical trial including healthy subjects with a low-to-medium cardiovascular risk profile, characterized by being overweight and by the presence of at least an additional metabolic risk factor (abdominal obesity, high total cholesterol, high LDL cholesterol, high triglycerides, impaired glucose fasting levels) but free from medications. A total of 100 subjects will be included and randomly assigned to two groups: Mediterranean calorie-restricted diet (n = 50) and vegetarian calorie-restricted diet (n = 50). The intervention phases will last 3 months each, and at the end of intervention phase I the groups will be crossed over. The two diets will be isocaloric and of three different sizes (1400 - 1600 - 1800 kcal/day), according to specific energy requirements. Adherence to the dietary intervention will be established through questionnaires and 24-h dietary recall. Anthropometric measurements, body composition, blood samples and stool samples will be obtained from each participant at the beginning and at the end of each intervention phase. The primary outcome measure will be change in weight from baseline. The secondary outcome measures will be variations of anthropometric and bioelectrical impedance variables as well as traditional and innovative cardiovascular biomarkers. Despite all the data supporting the efficacy of Mediterranean and vegetarian diets on the prevention of cardiovascular diseases, no studies have directly compared these two dietary profiles. The trial will test whether there are statistically significant differences between these dietary profiles in reducing the cardiovascular risk burden for the general population. ClinicalTrials.gov NCT02641834.
Aveyard, Paul; Griffin, Carl; Lawrence, Terry; Cheng, K K
2003-03-01
To examine the population impact and effectiveness of the Pro-Change smoking cessation course based on the Transtheoretical Model (TTM) compared to standard self-help smoking cessation literature. Randomized controlled trial. Sixty-five West Midlands general practices. Randomly sampled patients recorded as smokers by their general practitioners received an invitation letter and 2471 current smokers agreed. Responders were randomized to one of four interventions. The control group received standard self-help literature. In the Manual intervention group, participants received the Pro-Change system, a self-help workbook and three questionnaires at 3-monthly intervals, which generated individually tailored feedback. In the Phone intervention group, participants received the Manual intervention plus three telephone calls. In the Nurse intervention group, participants received the Manual intervention plus three visits to the practice nurse. Biochemically confirmed point prevalence of being quit and 6-month sustained abstinence, 12 months after study commencement. A total of 9.1% of registered current smokers participated, of whom 83.0% were not ready to quit. Less than half of participants returned questionnaires to generate second and third individualized feedback. Telephone calls reached 75% of those scheduled, but few participants visited the nurse. There were small differences between the three Pro-Change arms. The odds ratio (95% confidence intervals) for all Pro-Change arms combined versus the control arm were 1.50 (0.85-2.67) and 1.53 (0.76-3.10), for point prevalence and 6-month abstinence, respectively. This constitutes 2.1% of the TTM group versus 1.4% of the control group achieving confirmed 6-month sustained abstinence. There was no statistically significant benefit of the intervention apparent in this trial and the high relapse of quitters means that any population impact is small.
USDA-ARS?s Scientific Manuscript database
The genetic effects of long term random mating and natural selection aided by genetic male sterility (gms) were evaluated in two soybean [Glycine max (L.) Merr.] populations designated: RSII and RSIII. These populations were evaluated in the field at three locations each with two replications. Genot...
Population differentiation in Pacific salmon: local adaptation, genetic drift, or the environment?
Adkison, Milo D.
1995-01-01
Morphological, behavioral, and life-history differences between Pacific salmon (Oncorhynchus spp.) populations are commonly thought to reflect local adaptation, and it is likewise common to assume that salmon populations separated by small distances are locally adapted. Two alternatives to local adaptation exist: random genetic differentiation owing to genetic drift and founder events, and genetic homogeneity among populations, in which differences reflect differential trait expression in differing environments. Population genetics theory and simulations suggest that both alternatives are possible. With selectively neutral alleles, genetic drift can result in random differentiation despite many strays per generation. Even weak selection can prevent genetic drift in stable populations; however, founder effects can result in random differentiation despite selective pressures. Overlapping generations reduce the potential for random differentiation. Genetic homogeneity can occur despite differences in selective regimes when straying rates are high. In sum, localized differences in selection should not always result in local adaptation. Local adaptation is favored when population sizes are large and stable, selection is consistent over large areas, selective diffeentials are large, and straying rates are neither too high nor too low. Consideration of alternatives to local adaptation would improve both biological research and salmon conservation efforts.
Unexpectedly high bacteriochlorophyll a concentrations in neotropical tank bromeliads.
Lehours, Anne-Catherine; Jeune, Anne-Hélène Le; Aguer, Jean-Pierre; Céréghino, Régis; Corbara, Bruno; Kéraval, Benoit; Leroy, Céline; Perrière, Fanny; Jeanthon, Christian; Carrias, Jean-François
2016-06-06
The contribution of bacteriochlorophyll a (BChl a) to photosynthetically driven electron transport is generally low in aquatic and terrestrial systems. Here, we provide evidence that anoxygenic bacterial phototrophy is widespread and substantial in water retained by tank bromeliads of a primary rainforest in French Guiana. An analysis of the water extracted from 104 randomly selected tank bromeliads using infrared fluorimetry suggested the overall presence of abundant anoxygenic phototrophic bacterial populations. We found that purple bacteria dominated these populations responsible for unusually high BChl a/chlorophyll a ratios (>50%). Our data suggest that BChl a-based phototrophy in tank bromeliads can have significant effects on the ecology of tank-bromeliad ecosystems and on the carbon and energy fluxes in Neotropical forests. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.
Yan, Lijing L; Fang, Weigang; Delong, Elizabeth; Neal, Bruce; Peterson, Eric D; Huang, Yining; Sun, Ningling; Yao, Chen; Li, Xian; MacMahon, Stephen; Wu, Yangfeng
2014-04-11
The high-risk strategy has been proven effective in preventing cardiovascular disease; however, the population benefits from these interventions remain unknown. This study aims to assess, at the population level, the effects of an evidence-based high cardiovascular risk management program delivered by village doctors in rural China. The study will employ a cluster-randomized controlled trial in which a total of 120 villages in five northern provinces of China, will be assigned to either intervention (60 villages) or control (60 villages). Village doctors in intervention villages will be trained to implement a simple evidence-based management program designed to identify, treat and follow-up as many as possible individuals at high-risk of cardiovascular disease in the village. The intervention will also include performance feedback as well as a performance-based incentive payment scheme and will last for 2 years. We will draw two different (independent) random samples, before and after the intervention, 20 men aged≥50 years and 20 women aged≥60 years from each village in each sample and a total of 9,600 participants from 2 samples to measure the study outcomes at the population level. The primary outcome will be the pre-post difference in mean systolic blood pressure, analyzed with a generalized estimating equations extension of linear regression model to account for cluster effect. Secondary outcomes will include monthly clinic visits, provision of lifestyle advice, use of antihypertensive medications and use of aspirin. Process and economic evaluations will also be conducted. This trial will be the first implementation trial in the world to evaluate the population impact of the high-risk strategy in prevention and control of cardiovascular disease. The results are expected to provide important information (effectiveness, cost-effectiveness, feasibility and acceptability) to guide policy making for rural China as well as other resource-limited countries. The trial is registered at ClinicalTrials.gov (NCT01259700). Date of initial registration is December 13, 2010.
Elwin, Marie; Schröder, Agneta; Ek, Lena; Kjellin, Lars
2016-01-01
Unusual reactions to sensory stimuli are experienced by 90-95% of people with an autism spectrum condition (ASC). Self-reported sensory reactivity in ASC has mainly been measured with generic questionnaires developed and validated on data from the general population. Interest in sensory reactivity in ASC increased after the inclusion of hyper- and hypo-reactivity together with unusual sensory interest as diagnostic markers of ASC in the DSM-5. To develop and pilot validate a self-report questionnaire designed from first-hand descriptions of the target group of adults diagnosed with high functioning ASC. Psychometric properties of the questionnaire were evaluated on a sample of participants with ASC diagnoses (N = 71) and a random sample from the general population (N = 162). The Sensory Reactivity in Autism Spectrum (SR-AS is intended to be used as a screening tool in diagnostic processes with adults and for support in adapting compensating strategies and environmental adjustments. The internal consistency was high for both the SR-AS and its subscales. The total scale Cronbach's alpha was 0.96 and the subscales alphas were ≥ 0.80. Confirmatory factor analysis (CFA) showed best fit for a four-factor model of inter-correlated factors: hyper and hypo-reactivity, strong sensory interest and a sensory/motor factor. The questionnaire discriminated well between ASC-diagnosed participants and participants from the general population. The SR-AS displayed good internal consistency and discriminatory power and promising factorial validity.
Rocha, Bruno Alves; Azevedo, Lara Ferreira; Gallimberti, Matheus; Campiglia, Andres Dobal; Barbosa, Fernando
2015-01-01
Bisphenol A (BPA) is an endocrine and metabolic disruptor commonly employed as a color developer in thermal papers. Consequently, BPA derived from thermal papers has been considered an important source of exposure for humans, since this chemical may migrate from paper to skin upon contact. Further, due to recent restrictions on BPA use in some countries, it has been replaced by a new analogue, bisphenol S (BPS). The aim of the present study was to determine levels of BPA and BPS in 190 different thermal receipts, randomly collected from different locations in São Paulo State, Brazil, including receipts from supermarkets, general and fast-food restaurants, gas stations, bus and airplane tickets, and credit card and bank accounts. BPA and/or BPS were detected in 98% of samples at concentrations ranging from below the quantification limit to 4.3% (mg/100 mg paper). The obtained values were higher than amounts previously reported in other countries. The estimated daily intake through dermal absorption from handling of thermal receipt papers was estimated on the basis of concentrations and frequencies of handling of papers by humans in both the general population and occupationally exposed individuals. Fifth percentile, median, and 95th percentile daily intakes by the general population were 0.44, 1.42, and 2 μg/d, respectively, whereas the corresponding values for occupationally exposed population are 21.8, 71 and 101 μg/d. The potential adverse consequences of elevated occupational exposure are currently being examined.
Sasongko, Muhammad B; Agni, Angela N; Wardhana, Firman S; Kotha, Satya P; Gupta, Prateek; Widayanti, Tri W; Supanji; Widyaputri, Felicia; Widyaningrum, Rifa; Wong, Tien Y; Kawasaki, Ryo; Wang, Jie Jin; Pawiroranu, Suhardjo
2017-02-01
There are no available data about diabetic retinopathy (DR) in the Indonesian population. This report summarizes the rationale and study design of the Jogjakarta Eye Diabetic Study in the Community (JOGED.COM), a community-based study to estimate the prevalence and risk factors of DR in persons with type 2 diabetes in Jogjakarta, Indonesia. The JOGED.COM aimed to examine a cross-sectional sample of 1200 persons with type 2 diabetes aged 30 years and older residing in the study area. We identified 121 community health centers (CHCs) in Jogjakarta and listed 35 CHCs with non-communicable diseases facilities. Multi-stage, clustered random sampling was used to select 22 CHCs randomly. We included CHCs with coverage population >30,000, and excluded those classified as 100% rural. Lists of persons with diabetes confirmed by their family physician were provided from each CHC. Examinations procedures included detailed interviews, general and eye examinations, anthropometry and body composition scan, and dilated fundus photography. We collaborated with local health authorities, family physicians, and local health practitioners in the recruitment phase. A total of 1435 invitations were distributed, and 1184 people (82.5%) with type 2 diabetes participated in this study, of whom 1138 (79.3%) had completed data with gradable retinal images. JOGED.COM is the first epidemiologic study of DR in an Indonesian population. This study will provide key information about the prevalence and risk factors of DR in the community. These data are very important for future health promotion programs to reduce the burden of DR in the population.
Isonymy structure of Sucre and Táchira, two Venezuelan states.
Rodríguez-Larralde, A; Barrai, I
1997-10-01
The isonymy structure of two Venezuelan states, Sucre and Táchira, is described using the surnames of the Register of Electors updated in 1991. The frequency distribution of surnames pooled together by sex was obtained for the 57 counties of Sucre and the 52 counties of Táchira, based on total population sizes of 158,705 and 160,690 individuals, respectively. The coefficient of consanguinity resulting from random isonymy (phi ii), Karlin and McGregor's ni (identical to v), and the proportion of the population included in surnames represented only once (estimator A) and in the seven most frequent surnames (estimator B) were calculated for each county. RST, a measure of microdifferentiation, was estimated for each state. The Euclidean distance between pairs of counties within states was calculated together with the corresponding geographic distances. The correlations between their logarithmic transformations were significant in both cases, indicating differentiation of surnames by distance. Dendrograms based on the Euclidean distance matrix were constructed. From them a first approximation of the effect of internal migration within states was obtained. Ninety-six percent of the coefficient of consanguinity resulting from random isonymy is determined by the proportion of the population included in the seven most frequent surnames, whereas between 72% and 88% of Karlin and McGregor's ni for Sucre and Táchira, respectively, is determined by the proportion of population included in surnames represented only once. Surnames with generalized and with focal distribution were identified for both states, to be used as possible indicators of the geographic origin of their carriers. Our results indicate that Táchira's counties, on average, tend to be more isolated than Sucre's counties, as measured by RST, estimator B, and phi ii. Comparisons with the results obtained for other. Venezuelan states and other non-Venezuelan populations are also given.
Prevalence of diabetes mellitus and prediabetes in the adult Romanian population: PREDATORR study.
Mota, Maria; Popa, Simona Georgiana; Mota, Eugen; Mitrea, Adina; Catrinoiu, Doina; Cheta, Dan Mircea; Guja, Cristian; Hancu, Nicolae; Ionescu-Tirgoviste, Constantin; Lichiardopol, Radu; Mihai, Bogdan Mircea; Popa, Amorin Remus; Zetu, Cornelia; Bala, Cornelia Gabriela; Roman, Gabriela; Serafinceanu, Cristian; Serban, Viorel; Timar, Romulus; Veresiu, Ioan Andrei; Vlad, Adrian Radu
2016-05-01
The PREDATORR (PREvalence of DiAbeTes mellitus, prediabetes, overweight, Obesity, dyslipidemia, hyperuricemia and chronic kidney disease in Romania) study is the first national study analyzing the prevalence of diabetes mellitus (DM) and prediabetes, and their association with cardiometabolic, sociodemographic, and lifestyle risk factors in the Romanian population aged 20-79 years. This was an epidemiological study with a stratified, cross-sectional, cluster random sampling design. Sociodemographic, lifestyle, and anamnestic data were collected through self- and interviewer-administered questionnaires, and biochemical assays and oral glucose tolerance tests were performed. In all, 2728 participants from 101 clinics of general practitioners were randomly selected, with a probability proportional to population size according to the 2002 Romanian Census. The participation rate was 99.6%. Impaired glucose regulation (prediabetes, known and unknown DM) was found in 28.1% of the study population. The overall age- and sex-adjusted prevalence of DM was 11.6% (95% CI 9.6%-13.6%), of which 2.4% (95% CI 1.7%-3.1%) had unknown DM. The prevalence of DM increased with age and was higher in men than in women. The age- and sex-adjusted prevalence of prediabetes was 16.5% (95%CI 14.8%-18.2%), with the highest percentage in the 60-79 year age group and in women. Obesity, abdominal obesity, dyslipidemia, low education level, and a family history of diabetes were associated with glucose metabolism disorders. The PREDATORR study shows a high prevalence of impaired glucose regulation in the adult Romanian population, providing data on the prevalence of DM and prediabetes and their association with several risk factors. © 2015 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley Sons & Australia, Ltd.
Treweek, Shaun; Doney, Alex; Leiman, David
2009-01-01
There is increasing international interest in DNA biobanks but relatively little evidence concerning appropriate recruitment methods for these repositories of genetic information linked to patient-specific phenotypic data. To this end, our study aimed to investigate the attitudes of members of the public recruited through general practices to the donation and storage of blood left over from routine clinical tests in general practice. A questionnaire was mailed to 2600 individuals randomly selected from two general practice patient lists in Dundee, Scotland. Using a 7-point Likert scale, respondents rated their attitudes toward DNA biobanks in general, and procurement of blood samples specifically. Overall, 841 (34%) of 2471 delivered questionnaires were returned. Compared with patients on the practice lists, respondents were older and more likely to be women. A majority of respondents (61%) were unequivocally positive about storing blood left over from routine tests. Despite general support for this collection method, when asked about open-ended consent, respondents expressed concern about future uses. Respondents' increasing age and level of deprivation had significant adverse effects on attitudes towards making leftover routine biological samples available for research (P = 0.013 and P = 0.034, respectively). The study had three main limitations: there was a low response rate (34%) such that respondents were not entirely respresentative of the survey population; some respondents had difficulty with the questionnaire; and the study was somewhat underpowered for some comparisons. Despite its limitations, this first survey of a general practice population suggests that the majority would be willing to consider giving open-ended consent for the use of blood left over from routine clinical tests in general practice to be stored and used later for medical research.
Cruse-Sanders, J. M.; Hamrick, J.L.; Ahumada, J.A.
2005-01-01
American ginseng, Panax quinquefolius L., is one of the most heavily traded medicinal plants in North America. The effect of harvest on genetic diversity in ginseng was measured with a single generation culling simulation program. Culling scenarios included random harvest at varying levels, legal limit random harvest and legal limit mature plant harvest. The legal limit was determined by the proportion of legally harvestable plants per population (% mature plants per population). Random harvest at varying levels resulted in significant loss of genetic diversity, especially allelic richness. Relative to initial levels, average within-population genetic diversity (H e) was significantly lower when plants were culled randomly at the legal limit (Mann-Whitney U = 430, p < 0.001) or when only mature plants were culled (Mann-Whitney U = 394, p < 0.01). Within-population genetic diversity was significantly higher with legal limit mature plant harvest (H e = 0.068) than when plants were culled randomly at the legal limit (H e = 0.064; U = 202, p < 0.01). Based on these simulations of harvest over one generation, we recommend that harvesting fewer than the proportion of mature plants could reduce the negative genetic effects of harvest on ginseng populations. ?? Springer 2005.
The quality of life, mental health, and perceived stigma of leprosy patients in Bangladesh.
Tsutsumi, Atsuro; Izutsu, Takashi; Islam, Akramul Md; Maksuda, A N; Kato, Hiroshi; Wakai, Susumu
2007-06-01
The present study aims to determine the quality of life (QOL) and general mental health of leprosy patients compared with the general population, and evaluate contributing factors such as socio-economic characteristics and perceived stigma. A total of 189 patients (160 outpatients, 29 inpatients) and 200 controls without leprosy or other chronic diseases were selected from Dhaka district, Bangladesh, using stratified random sampling. A Bangladeshi version of a structured questionnaire including socio-demographic characteristics-the Bangla version of the World Health Organization Quality of Life Assessment BREF (WHOQOL-BREF)-was used to assess QOL; a Self-Reporting Questionnaire (SRQ) was used to evaluate general mental health; the Barthel Index to control activities of daily living (ADL); and the authors' Perceived Stigma Questionnaire was used to assess perceived stigma of patients with leprosy. Medical records were examined to evaluate disability grades and impairment. QOL and general mental health scores of leprosy patients were worse than those of the general population. Multiple regression analysis revealed that factors potentially contributing to the deteriorated QOL of leprosy patients were the presence of perceived stigma, fewer years of education, the presence of deformities, and a lower annual income. Perceived stigma showed the greatest association with adverse QOL. We conclude that there is an urgent need for interventions sensitive to the effects of perceived stigma, gender, and medical conditions to improve the QOL and mental health of Bangladeshi leprosy patients.
Tran, Kathy V; Azhar, Gulrez S; Nair, Rajesh; Knowlton, Kim; Jaiswal, Anjali; Sheffield, Perry; Mavalankar, Dileep; Hess, Jeremy
2013-06-18
Extreme heat is a significant public health concern in India; extreme heat hazards are projected to increase in frequency and severity with climate change. Few of the factors driving population heat vulnerability are documented, though poverty is a presumed risk factor. To facilitate public health preparedness, an assessment of factors affecting vulnerability among slum dwellers was conducted in summer 2011 in Ahmedabad, Gujarat, India. Indicators of heat exposure, susceptibility to heat illness, and adaptive capacity, all of which feed into heat vulnerability, was assessed through a cross-sectional household survey using randomized multistage cluster sampling. Associations between heat-related morbidity and vulnerability factors were identified using multivariate logistic regression with generalized estimating equations to account for clustering effects. Age, preexisting medical conditions, work location, and access to health information and resources were associated with self-reported heat illness. Several of these variables were unique to this study. As sociodemographics, occupational heat exposure, and access to resources were shown to increase vulnerability, future interventions (e.g., health education) might target specific populations among Ahmedabad urban slum dwellers to reduce vulnerability to extreme heat. Surveillance and evaluations of future interventions may also be worthwhile.
Yun, Lai Shin; Hassan, Yahaya; Aziz, Noorizan Abd; Awaisu, Ahmed; Ghazali, Rozina
2007-12-01
The primary objective of this study was to assess and compare the knowledge of diabetes mellitus possessed by patients with diabetes and healthy adult volunteers in Penang, Malaysia. A cross-sectional study was conducted from 20 February 2006 to 31 March 2006. We randomly selected 120 patients with diabetes mellitus from a diabetic clinic at the General Hospital Penang, Malaysia and 120 healthy adults at a shopping complex in Penang. Each participant was interviewed face-to-face by a pharmacist using a validated questionnaire, and they were required to answer a total of 30 questions concerning knowledge about diabetes mellitus using Yes, No or Unsure as the only response. The results showed that patients with diabetes mellitus were significantly more knowledgeable than the healthy volunteers about risk factors, symptoms, chronic complications, treatment and self-management, and monitoring parameters. Educational level was the best predictive factor for diabetes mellitus and public awareness. Knowledge about diabetes mellitus should be improved among the general population. This study has major implications for the design of an educational programme for diabetics and a health promotion programme as a primary prevention measure for the healthy population in general, and especially for those at high risk. The results could be useful in the design of future studies for evaluating patients' and the general public's knowledge about diabetes mellitus.
Matthias, James; Zielinski-Gutierrez, Emily C; Tisch, Daniel J; Stanek, Danielle; Blanton, Ronald E; Doyle, Michael S; Eadie, Robert B; Gazdick, Elizabeth J; Leal, Andrea L; Pattison, Kimberly J; Perez-Guerra, Carmen L; Tittel, Christopher J; Vyas, Jooi; Wagner, Todd; Blackmore, Carina G M
2014-11-01
In 2009-2010, 93 cases of dengue were identified in Key West, Florida. This was the first outbreak of autochthonous transmission of dengue in Florida since 1934. In response to this outbreak, a multifaceted public education outreach campaign was launched. The aim of this study is to compare dengue prevention knowledge, attitudes, perceptions, and prevention practices among residents of subsidized public housing to the general population in Key West and to assess whether there were barriers preventing effective outreach from reaching specific vulnerable populations. A randomized population-based evaluation of knowledge, attitudes, and behaviors toward dengue prevention consisting of 521 separate household interviews was undertaken in July of 2011. A subset analysis was performed on interviews collected from 28 public housing units within four subsidized public housing complexes. Analysis was performed to determine whether knowledge, attitudes, and behaviors exhibited by public housing residents differed from the non-public housing study population. Public housing residents recalled fewer outreach materials (p=0.01) and were 3.4 times (95% confidence interval [CI] 1.4-8.3) more likely not to recall any outreach materials. Public housing residents were less likely to correctly identify how dengue transmission occurs (61% vs. 89%), where mosquitoes lay their eggs (54% vs. 85%), or to identify any signs or symptoms related to dengue (36% vs. 64%). Public housing residents were less likely to perform dengue prevention practices such as removing standing water or always using air conditioning. Examination of public housing residents identified an at-risk population that recalled less exposure to outreach materials and had less knowledge about dengue infection and prevention than the randomized study population. This provides public health systems the opportunity to target or modify future health messages and interventions to this group. Differences identified in the demographics of this population suggest that alternative methods or non-English materials may be required to reach desired outcomes.
Thomas, D.L.; Johnson, D.; Griffith, B.
2006-01-01
Modeling the probability of use of land units characterized by discrete and continuous measures, we present a Bayesian random-effects model to assess resource selection. This model provides simultaneous estimation of both individual- and population-level selection. Deviance information criterion (DIC), a Bayesian alternative to AIC that is sample-size specific, is used for model selection. Aerial radiolocation data from 76 adult female caribou (Rangifer tarandus) and calf pairs during 1 year on an Arctic coastal plain calving ground were used to illustrate models and assess population-level selection of landscape attributes, as well as individual heterogeneity of selection. Landscape attributes included elevation, NDVI (a measure of forage greenness), and land cover-type classification. Results from the first of a 2-stage model-selection procedure indicated that there is substantial heterogeneity among cow-calf pairs with respect to selection of the landscape attributes. In the second stage, selection of models with heterogeneity included indicated that at the population-level, NDVI and land cover class were significant attributes for selection of different landscapes by pairs on the calving ground. Population-level selection coefficients indicate that the pairs generally select landscapes with higher levels of NDVI, but the relationship is quadratic. The highest rate of selection occurs at values of NDVI less than the maximum observed. Results for land cover-class selections coefficients indicate that wet sedge, moist sedge, herbaceous tussock tundra, and shrub tussock tundra are selected at approximately the same rate, while alpine and sparsely vegetated landscapes are selected at a lower rate. Furthermore, the variability in selection by individual caribou for moist sedge and sparsely vegetated landscapes is large relative to the variability in selection of other land cover types. The example analysis illustrates that, while sometimes computationally intense, a Bayesian hierarchical discrete-choice model for resource selection can provide managers with 2 components of population-level inference: average population selection and variability of selection. Both components are necessary to make sound management decisions based on animal selection.
ERIC Educational Resources Information Center
Wang, Wen-Chung; Liu, Chen-Wei; Wu, Shiu-Lien
2013-01-01
The random-threshold generalized unfolding model (RTGUM) was developed by treating the thresholds in the generalized unfolding model as random effects rather than fixed effects to account for the subjective nature of the selection of categories in Likert items. The parameters of the new model can be estimated with the JAGS (Just Another Gibbs…
The Role of BMI Change on Smoking Abstinence in a Sample of HIV-Infected Smokers
Gritz, Ellen R.; Kypriotakis, George; Arduino, Roberto C.; Vidrine, Damon J.
2016-01-01
The prevalence of cigarette smoking among persons living with HIV/AIDS (PLWHA) is approximately 40%, significantly higher than that of the general population. Identifying predictors of successful smoking cessation for PLWHA is necessary to alleviate the morbidity and mortality associated with smoking in this population. Weight gain has been associated with smoking relapse in the general population, but has not been studied among PLWHA. Data from 474 PLWHA enrolled in a smoking cessation randomized clinical trial were analyzed to examine the effect of BMI change, from baseline to 3-month follow-up, on smoking outcomes using multiple logistic regression. The odds of 7-day smoking abstinence at 3-month follow-up were 4.22 (95% CI=1.65, 10.82) times higher for participants classified as BMI decrease and 4.22 (95% CI=1.62, 11.01) times higher for participants classified as BMI increase as compared to participants with a minimal increase or decrease in BMI. In this sample, both weight gain and loss following smoking cessation were significantly associated with abstinence at 3-month follow-up among HIV-infected smokers. Further research and a better understanding of predictors of abstinence will encourage more tailored interventions, with the potential to reduce morbidity and mortality. PMID:26666313
Visiting Entertainment Venues and Sexual Health in China
Li, Li; Wu, Zunyou; Rotheram-Borus, Mary Jane; Guan, Jihui; Yin, Yueping; Detels, Roger; Wu, Sheng; Lee, Sung-Jae; Cao, Haijun; Lin, Chunqing; Rou, Keming; Liu, Zhendong
2010-01-01
Entertainment venues in China are associated with risky sexual behavior. Most previous studies related to entertainment venues in China have focused on sex workers and commercial sex, but this study addressed sexual health in a sample of the general urban population. A randomly selected sample of market vendors (n = 4,510) from an eastern city was recruited and assessed to examine relationships between entertainment venue visits and sexual risk. Both behavioral (self-reports of unprotected sex) and biomedical (STD test results) measures were used. About 18% of the sample (26.8% of men and 9% of women) reported visiting entertainment venues in the past 30 days. Those who visited entertainment venues were more likely to be male, younger, single, with higher education, and to have more discretionary income. For both men and women, visiting entertainment venues was a significant predictor for unprotected sex and STD infection. Gender differences were observed in predicting unprotected sex and STD infections. Entertainment venues could be potential sites for place-based intervention programs and out-reach for the general population. PMID:18256918
Yip, T C-F; Ma, A J; Wong, V W-S; Tse, Y-K; Chan, H L-Y; Yuen, P-C; Wong, G L-H
2017-08-01
Non-alcoholic fatty liver disease (NAFLD) affects 20%-40% of the general population in developed countries and is an increasingly important cause of hepatocellular carcinoma. Electronic medical records facilitate large-scale epidemiological studies, existing NAFLD scores often require clinical and anthropometric parameters that may not be captured in those databases. To develop and validate a laboratory parameter-based machine learning model to detect NAFLD for the general population. We randomly divided 922 subjects from a population screening study into training and validation groups; NAFLD was diagnosed by proton-magnetic resonance spectroscopy. On the basis of machine learning from 23 routine clinical and laboratory parameters after elastic net regulation, we evaluated the logistic regression, ridge regression, AdaBoost and decision tree models. The areas under receiver-operating characteristic curve (AUROC) of models in validation group were compared. Six predictors including alanine aminotransferase, high-density lipoprotein cholesterol, triglyceride, haemoglobin A 1c , white blood cell count and the presence of hypertension were selected. The NAFLD ridge score achieved AUROC of 0.87 (95% CI 0.83-0.90) and 0.88 (0.84-0.91) in the training and validation groups respectively. Using dual cut-offs of 0.24 and 0.44, NAFLD ridge score achieved 92% (86%-96%) sensitivity and 90% (86%-93%) specificity with corresponding negative and positive predictive values of 96% (91%-98%) and 69% (59%-78%), and 87% of overall accuracy among 70% of classifiable subjects in the validation group; 30% of subjects remained indeterminate. NAFLD ridge score is a simple and robust reference comparable to existing NAFLD scores to exclude NAFLD patients in epidemiological studies. © 2017 John Wiley & Sons Ltd.
Djukanovic, Ingrid; Carlsson, Jörg; Årestedt, Kristofer
2017-10-04
The HADS (Hospital Anxiety and Depression Scale) aims to measure symptoms of anxiety (HADS Anxiety) and depression (HADS Depression). The HADS is widely used but has shown ambiguous results both regarding the factor structure and sex differences in the prevalence of depressive symptoms. There is also a lack of psychometric evaluations of the HADS in non-clinical samples of older people. The aim of the study was to evaluate the factor structure of the HADS in a general population 65-80 years old and to exam possible presence of differential item functioning (DIF) with respect to sex. This study was based on data from a Swedish sample, randomized from the total population in the age group 65-80 years (n = 6659). Confirmatory factor analyses (CFA) were performed to examine the factor structure. Ordinal regression analyses were conducted to detect DIF for sex. Reliability was examined by both ordinal as well as traditional Cronbach's alpha. The CFA showed a two-factor model with cross-loadings for two items (7 and 8) had excellent model fit. Internal consistency was good in both subscales, measured with ordinal and traditional alpha. Floor effects were presented for all items. No indication for meaningful DIF regarding sex was found for any of the subscales. HADS Anxiety and HADS Depression are unidimensional measures with acceptable internal consistency and are invariant with regard to sex. Despite pronounced ceiling effects and cross-loadings for item 7 and 8, the hypothesized two-factor model of HADS can be recommended to assess psychological distress among a general population 65-80 years old.
Gómez, Miquel; Vila, Joan; Elosua, Roberto; Molina, Lluís; Bruguera, Jordi; Sala, Joan; Masià, Rafel; Covas, Maria Isabel; Marrugat, Jaume; Fitó, Montserrat
2014-01-01
To assess 1) the association of lipid oxidation biomarkers with 10-year coronary artery disease (CAD) events and subclinical atherosclerosis, and 2) the reclassification capacity of these biomarkers over Framingham-derived CAD risk functions, in a general population. Within the framework of the REGICOR study, 4782 individuals aged between 25 and 74 years were recruited in a population-based cohort study. Follow-up of the 4042 who met the eligibility criteria was carried out. Plasma, circulating oxidized low-density lipoprotein (oxLDL) and oxLDL antibodies (OLAB) were measured in a random sample of 2793 participants. End-points included fatal and non-fatal acute myocardial infarction (AMI) and angina. Carotid intima-media thickness (IMT) in the highest quintile and ankle-brachial index <0.9 were considered indicators of subclinical atherosclerosis. Mean age was 50.0 (13.4) years, and 52.4% were women. There were 103 CAD events (34 myocardial infarction, 43 angina, 26 coronary deaths), and 306 subclinical atherosclerosis cases. Oxidized LDL was independently associated with higher incidence of CAD events (HR = 1.70; 95% Confidence Interval: 1.02-2.84), but not with subclinical atherosclerosis. The net classification index of the Framingham-derived CAD risk function was significantly improved when ox-LDL was included (NRI = 14.67% [4.90; 24.45], P = 0.003). No associations were found between OLAB and clinical or subclinical events. The reference values for oxLDL and OLAB are also provided (percentiles). OxLDL was independently associated with 10-year CAD events but not subclinical atherosclerosis in a general population, and improved the reclassification capacity of Framingham-derived CAD risk functions. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Formulation and Application of the Hierarchical Generalized Random-Situation Random-Weight MIRID
ERIC Educational Resources Information Center
Hung, Lai-Fa
2011-01-01
The process-component approach has become quite popular for examining many psychological concepts. A typical example is the model with internal restrictions on item difficulty (MIRID) described by Butter (1994) and Butter, De Boeck, and Verhelst (1998). This study proposes a hierarchical generalized random-situation random-weight MIRID. The…
Randomly amplified polymorphic DNA linkage relationships in different Norway spruce populations
M. Troggio; Thomas L. Kubisiak; G. Bucci; P. Menozzi
2001-01-01
We tested the constancy of linkage relationships of randomly amplified polymorphic DNA (RAPD) marker loci used to construct a population-based consensus map in material from an Italian stand of Picea abies (L.) Karst. in 29 individuals from three Norwegian populations. Thirteen marker loci linked in the Italian stand did show a consistent locus...
Yoga for veterans with chronic low back pain: Design and methods of a randomized clinical trial.
Groessl, Erik J; Schmalzl, Laura; Maiya, Meghan; Liu, Lin; Goodman, Debora; Chang, Douglas G; Wetherell, Julie L; Bormann, Jill E; Atkinson, J Hamp; Baxi, Sunita
2016-05-01
Chronic low back pain (CLBP) afflicts millions of people worldwide, with particularly high prevalence in military veterans. Many treatment options exist for CLBP, but most have limited effectiveness and some have significant side effects. In general populations with CLBP, yoga has been shown to improve health outcomes with few side effects. However, yoga has not been adequately studied in military veteran populations. In the current paper we will describe the design and methods of a randomized clinical trial aimed at examining whether yoga can effectively reduce disability and pain in US military veterans with CLBP. A total of 144 US military veterans with CLBP will be randomized to either yoga or a delayed treatment comparison group. The yoga intervention will consist of 2× weekly yoga classes for 12weeks, complemented by regular home practice guided by a manual. The delayed treatment group will receive the same intervention after six months. The primary outcome is the change in back pain-related disability measured with the Roland-Morris Disability Questionnaire at baseline and 12-weeks. Secondary outcomes include pain intensity, pain interference, depression, anxiety, fatigue/energy, quality of life, self-efficacy, sleep quality, and medication usage. Additional process and/or mediational factors will be measured to examine dose response and effect mechanisms. Assessments will be conducted at baseline, 6-weeks, 12-weeks, and 6-months. All randomized participants will be included in intention-to-treat analyses. Study results will provide much needed evidence on the feasibility and effectiveness of yoga as a therapeutic modality for the treatment of CLBP in US military veterans. Published by Elsevier Inc.
Lesmerises, Rémi; St-Laurent, Martin-Hugues
2017-11-01
Habitat selection studies conducted at the population scale commonly aim to describe general patterns that could improve our understanding of the limiting factors in species-habitat relationships. Researchers often consider interindividual variation in selection patterns to control for its effects and avoid pseudoreplication by using mixed-effect models that include individuals as random factors. Here, we highlight common pitfalls and possible misinterpretations of this strategy by describing habitat selection of 21 black bears Ursus americanus. We used Bayesian mixed-effect models and compared results obtained when using random intercept (i.e., population level) versus calculating individual coefficients for each independent variable (i.e., individual level). We then related interindividual variability to individual characteristics (i.e., age, sex, reproductive status, body condition) in a multivariate analysis. The assumption of comparable behavior among individuals was verified only in 40% of the cases in our seasonal best models. Indeed, we found strong and opposite responses among sampled bears and individual coefficients were linked to individual characteristics. For some covariates, contrasted responses canceled each other out at the population level. In other cases, interindividual variability was concealed by the composition of our sample, with the majority of the bears (e.g., old individuals and bears in good physical condition) driving the population response (e.g., selection of young forest cuts). Our results stress the need to consider interindividual variability to avoid misinterpretation and uninformative results, especially for a flexible and opportunistic species. This study helps to identify some ecological drivers of interindividual variability in bear habitat selection patterns.
Morimoto, Akiko; Miyamatsu, Naomi; Okamura, Tomonori; Nakayama, Hirohumi; Morinaga, Miho; Toyota, Akihiro; Suzuki, Kazuo; Hata, Takashi; Yamaguchi, Takenori
2010-10-01
We examined the knowledge regarding heavy drinking and smoking as risk factors of stroke according to drinking/smoking habits among randomly selected Japanese general population. The Japan Stroke Association and co-researchers have performed a large-scale educational intervention to improve knowledge concerning stroke from 2006 to 2008. Prior to above-mentioned intervention, we conducted mail-surveillance on knowledge about stroke in 11,306 randomly selected residents aged 40 to 74. We assessed the relationship between drinking/smoking habits and knowledge regarding heavy drinking and smoking as risk factors by using the chi-square test and multiple logistic regression analysis adjusting for age, sex, area, employment, living situation, history of stroke and other stroke related diseases, history of liver disease, family history of stroke and drinking (non-drinker / ex-drinker / occasional drinker / habitual drinker) / smoking habits (non-smoker / ex-smoker / current smoker). Total 5,540 subjects (49.0%) participated in this study. Ex-smokers and current smokers had better knowledge regarding smoking as a risk factor of stroke than non-smokers (odds ratio and 95% confidence intervals: 1.89, 1.55-2.31, 1.76, 1.45-2.12, respectively). There was no difference between habitual drinkers and non-drinkers in their knowledge, whereas current smokers had greater knowledge regarding smoking than nonsmokers. Accordingly, it is suggested that it will be necessary for habitual drinkers to be enlightened regarding heavy drinking as a risk factor of stroke and for current smokers to be provided with information regarding not only these risks but also the specific strategies for invoking behavioral changes.
Uhlig, Christopher; Bluth, Thomas; Schwarz, Kristin; Deckert, Stefanie; Heinrich, Luise; De Hert, Stefan; Landoni, Giovanni; Serpa Neto, Ary; Schultz, Marcus J; Pelosi, Paolo; Schmitt, Jochen; Gama de Abreu, Marcelo
2016-06-01
It is not known whether modern volatile anesthetics are associated with less mortality and postoperative pulmonary or other complications in patients undergoing general anesthesia for surgery. A systematic literature review was conducted for randomized controlled trials fulfilling following criteria: (1) population: adult patients undergoing general anesthesia for surgery; (2) intervention: patients receiving sevoflurane, desflurane, or isoflurane; (3) comparison: volatile anesthetics versus total IV anesthesia or volatile anesthetics; (4) reporting on: (a) mortality (primary outcome) and (b) postoperative pulmonary or other complications; (5) study design: randomized controlled trials. The authors pooled treatment effects following Peto odds ratio (OR) meta-analysis and network meta-analysis methods. Sixty-eight randomized controlled trials with 7,104 patients were retained for analysis. In cardiac surgery, volatile anesthetics were associated with reduced mortality (OR = 0.55; 95% CI, 0.35 to 0.85; P = 0.007), less pulmonary (OR = 0.71; 95% CI, 0.52 to 0.98; P = 0.038), and other complications (OR = 0.74; 95% CI, 0.58 to 0.95; P = 0.020). In noncardiac surgery, volatile anesthetics were not associated with reduced mortality (OR = 1.31; 95% CI, 0.83 to 2.05, P = 0.242) or lower incidences of pulmonary (OR = 0.67; 95% CI, 0.42 to 1.05; P = 0.081) and other complications (OR = 0.70; 95% CI, 0.46 to 1.05; P = 0.092). In cardiac, but not in noncardiac, surgery, when compared to total IV anesthesia, general anesthesia with volatile anesthetics was associated with major benefits in outcome, including reduced mortality, as well as lower incidence of pulmonary and other complications. Further studies are warranted to address the impact of volatile anesthetics on outcome in noncardiac surgery.
Kilburn, Tina R; Sørensen, Merete Juul; Thastum, Mikael; Rapee, Ronald M; Rask, Charlotte Ulrikka; Arendt, Kristian Bech; Thomsen, Per Hove
2018-04-02
Autism spectrum disorder (ASD) is found in approximately 1% of the population and includes core symptoms that affect general and social development. Beside these core symptoms, it is suggested that up to 60% of children with ASD suffer from comorbid anxiety disorders which may further affect educational, social and general development as well as quality of life. The main goal of this study is to examine the effectiveness of a manualized cognitive behavioral therapy (CBT) anxiety program adapted for children with ASD. This study is a randomized controlled trial (RCT). Fifty children with ASD and anxiety, aged 7 to 13 years, will be randomly assigned to group CBT or a wait-list control (WL) condition. The design will follow a two (CBT and WL) by two (pre-post assessment) mixed between-within design. The control group will receive intervention after the waitlist period of 13 weeks. Primary outcomes are diagnostic status and severity of the anxiety disorders, measured with The Anxiety Disorder Interview Schedule for DSM-IV, Parent and Child Versions. Secondary outcomes are parent and child ratings on questionnaires on the child's level of anxiety and impact on everyday life. Additional outcomes entail information gathered from parents, child and teachers on the child's behavior and negative self-statements, together with social and adaptive skills. Follow-up data will be collected 3 months after intervention. This study aims to evaluate the effectiveness of a manualized CBT program in Danish children with ASD and anxiety within a mental health clinic setting. The hypothesis is that training anxiety reduction skills will decrease anxiety in children, as well as ensure better psychosocial development for the child in general. https://ClinicalTrials.gov ( NCT02908321 ). Registered 19th of September 2016.
Kamperman, Astrid M.; Henrichs, Jens; Bogaerts, Stefan; Lesaffre, Emmanuel M. E. H.; Wierdsma, André I.; Ghauharali, Razia R. R.; Swildens, Wilma; Nijssen, Yolanda; van der Gaag, Mark; Theunissen, Jan R.; Delespaul, Philippe A.; van Weeghel, Jaap; van Busschbach, Jooske T.; Kroon, Hans; Teplin, Linda A.; van de Mheen, Dike; Mulder, Cornelis L.
2014-01-01
Background Although crime victimisation is as prevalent in psychiatric patients as crime perpetration (and possibly more so), few European figures for it are available. We therefore assessed its one-year prevalence and incident rates in Dutch severely mentally ill outpatients, and compared the results with victimisation rates in the general population. Method This multisite epidemiological survey included a random sample of 956 adult severely mentally ill outpatients. Data on victimisation were obtained using the victimisation scale of the Dutch Crime and Victimisation Survey, which assesses crime victimisation over the preceding 12 months. Comparison data were derived from the nationwide survey on safety and victimisation in the Netherlands. Prevalence and incident rates were weighted for sex, age, ethnicity and socioeconomic status, and compared with a general population sample matched by region (N = 38,227). Results In the past year, almost half of the severely mentally ill outpatients (47%) had been victim of a crime. After control for demographic differences, prevalence rates of overall and specific victimisation measures were significantly higher in severely mentally ill outpatients than in the general population. The relative rates were especially high for personal crimes such as violent threats (RR = 2.12, 95% CI: 1.72–2.61), physical assaults (RR = 4.85, 95% CI: 3.69–6.39) and sexual harassment and assaults (RR = 3.94, 95% CI: 3.05–5.09). In concordance, severely mentally ill outpatients reported almost 14 times more personal crime incidents than persons from the general population (IRR = 13.68, 95% CI: 12.85–14.56). Conclusion Crime victimisation is a serious problem in Dutch severely mentally ill outpatients. Mental-healthcare institutions and clinicians should become aware of their patients’ victimisation risk, and should implement structural measures to detect and prevent (re-)victimisation. PMID:24609108
Gender variance in childhood and sexual orientation in adulthood: a prospective study.
Steensma, Thomas D; van der Ende, Jan; Verhulst, Frank C; Cohen-Kettenis, Peggy T
2013-11-01
Several retrospective and prospective studies have reported on the association between childhood gender variance and sexual orientation and gender discomfort in adulthood. In most of the retrospective studies, samples were drawn from the general population. The samples in the prospective studies consisted of clinically referred children. In understanding the extent to which the association applies for the general population, prospective studies using random samples are needed. This prospective study examined the association between childhood gender variance, and sexual orientation and gender discomfort in adulthood in the general population. In 1983, we measured childhood gender variance, in 406 boys and 473 girls. In 2007, sexual orientation and gender discomfort were assessed. Childhood gender variance was measured with two items from the Child Behavior Checklist/4-18. Sexual orientation was measured for four parameters of sexual orientation (attraction, fantasy, behavior, and identity). Gender discomfort was assessed by four questions (unhappiness and/or uncertainty about one's gender, wish or desire to be of the other gender, and consideration of living in the role of the other gender). For both men and women, the presence of childhood gender variance was associated with homosexuality for all four parameters of sexual orientation, but not with bisexuality. The report of adulthood homosexuality was 8 to 15 times higher for participants with a history of gender variance (10.2% to 12.2%), compared to participants without a history of gender variance (1.2% to 1.7%). The presence of childhood gender variance was not significantly associated with gender discomfort in adulthood. This study clearly showed a significant association between childhood gender variance and a homosexual sexual orientation in adulthood in the general population. In contrast to the findings in clinically referred gender-variant children, the presence of a homosexual sexual orientation in adulthood was substantially lower. © 2012 International Society for Sexual Medicine.
Hagel, Sofia; Petersson, Ingemar F; Bremander, Ann; Lindqvist, Elisabet; Bergknut, Charlotte; Englund, Martin
2013-07-01
To study 21st century trends in healthcare utilisation by patients with rheumatoid arthritis (RA) compared with the general population. Observational cohort study. Using Swedish healthcare register data, we identified 3977 Region Skåne residents (mean age in 2001, 62.7 years; 73% women) presenting with RA (International Classification of Diseases-10 codes M05 or M06) in 1998-2001. We randomly sampled two referents from the general population per RA patient matched for age, sex and area of residence. We calculated the year 2001-2010 trends for the annual ratio (RA cohort/referents) of the mean number of hospitalisations and outpatient clinic visits. By the end of the 10-year period, 62% of patients and 74% of referents were still alive and resident in the region. From 2001 to 2010, the ratio (RA cohort/referents) of the mean number of hospitalisations for men and women decreased by 27% (p=0.01) and 28% (p=0.004), respectively. The corresponding decrease was 29% (p=0.005) and 16% (p=0.004) for outpatient physician care, 34% (p=0.009) and 18% (p=0.01) for nurse visits, and 34% (p=0.01) and 28% (p=0.004) for physiotherapy. The absolute reduction in number of hospitalisations was from an annual mean of 0.79 to 0.69 in male patients and from 0.71 to 0.59 in female patients. The corresponding annual mean number of consultations in outpatient physician care by male and female RA patients changed from 9.2 to 7.7 and from 9.9 to 8.7, respectively. During the first decade of the 21st century, coinciding with increasing use of earlier and more active RA treatment including biological treatment, overall inpatient and outpatient healthcare utilisation by a cohort of patients with RA decreased relative to the general population.
Descriptive epidemiology of stigma against depression in a general population sample in Alberta.
Cook, Trevor M; Wang, Jianli
2010-04-19
Mental health illnesses, such as depression, are responsible for a growing disease burden worldwide. Unfortunately, effective treatment is often impeded by stigmatizing attitudes of other individuals, which have been found to lead to a number of negative consequences including reduced help-seeking behavior and increased social distance. Despite the high prevalence of depression in Canada, little research has been conducted to examine stigma against depression in the Canadian general population. Such information is crucial to understanding the current state of stigmatizing attitudes in the Canadian communities, and framing future stigma reduction initiatives. The objectives of this study were to estimate the percentages of various stigmatizing attitudes toward depression in a general population sample and to compare the percentages by demographics and socioeconomic characteristics. We conducted a cross-sectional telephone survey in Alberta, Canada, between February and June 2006. Random digit dialing was used to recruit participants who were aged 18-74 years old (n = 3047). Participants were presented a case vignette describing a depressed individual, and responded to a 9-item Personal Stigma questionnaire. The percentages of stigmatizing attitudes were estimated and compared by demographic and socioeconomic variables. Among the participants, 45.9% endorsed that depressed individuals were unpredictable and 21.9% held the view that people with depression were dangerous. Significant differences in stigmatizing attitudes were found by gender, age, education, and immigration status. A greater proportion of men than women held stigmatizing views on each stigma item. No consistent trend emerged by age in stigma against depression. Participants with higher levels of education reported less stigmatizing attitudes than those with less education. Participants who were not born in Canada were more likely to hold stigmatizing attitudes than those who were born in Canada. In the general population, stigmatizing attitudes towards depression differ by demographic characteristics. Men, those with less education and immigrants should be the targets of stigma reduction campaigns.
Vancampfort, Davy; Mitchell, Alex J; De Hert, Marc; Sienaert, Pascal; Probst, Michel; Buys, Roselien; Stubbs, Brendon
2015-10-01
Patients with depression may be at increased risk of type 2 diabetes mellitus (T2DM), which is a risk factor for cardiovascular diseases and premature mortality. We aimed to clarify the prevalence and predictors of T2DM in patients with major depressive disorder (MDD) and where possible compare the prevalence of T2DM in those with MDD versus general population controls. We searched major electronic databases until December 2014 for studies reporting T2DM prevalence in patients with MDD. Two independent authors extracted data and completed methodological quality appraisal in accordance with the meta-analysis of observational studies in epidemiology (MOOSE) guidelines. A random effects meta-analysis was utilized. The initial electronic database search resulted in 145 valid hits and 16 publications with clearly defined MDD (n = 15,8834; 31% male; mean age = 39-78 years) met the eligibility criteria. The overall prevalence of T2DM was 8.7% (95% confidence interval [CI] = 7.3-10.2%). Mean age of the MDD sample predicted a higher prevalence of T2DM (β = 0.0411; 95% CI = 0.0032-0.079, P = .03; R² = .22). A comparative meta-analysis revealed people with MDD (n = 154,366) had a higher risk of T2DM versus general controls (n = 2,098,063; relative risk [RR] = 1.49; 95% CI = 1.29-1.72; P < 0.001, N = 10). The RR (N = 3) focusing on age- and gender-matched general population controls (n = 103,555) was 1.36 (95% CI = 1.28-1.44; P < 0.001, n [MDD] = 10,895). T2DM is significantly more common in people with MDD compared with the general population. The current meta-analysis indicates that action is needed in order to curb the diabetes epidemic in this high-risk population. © 2015 Wiley Periodicals, Inc.
Boaz, Mona; Matas, Zipora; Chaimy, Tova; Landau, Zohar; Bar Dayan, Yosefa; Berlovitz, Yitzhak; Wainstein, Julio
2013-11-01
Acute physiological stress has been shown to impair glucose homeostasis. War is a period of acute psychological stress, and its effect on glucose control is unknown. In this study random point-of-care (POC) glucose levels were measured using an automated, institutional glucometer in hospitalized adult patients prior to versus during the Israeli Pillar of Defense campaign (November 7-10, 2012). Random POC glucose values measured with the institutional blood glucose monitoring system were obtained 1 week prior to the Pillar of Defense campaign (November 7-10, 2012) and compared with values to those obtained during the first 4 days of the war (November 14-17, 2012). In total, 3,573 POC glucose measures were included: 1,865 during the pre-war period and 1,708 during the campaign. POC glucose measures were significantly higher during the war compared with the week preceding the war: 9.7±4.7 versus 9.3±4.2 mmol/L (P=0.02). In a general linear model, period (pre-war vs. during war) persisted as a significant predictor of POC glucose even after controlling for age, sex, and department type (internal medicine vs. surgical). Acute stress, such as a wartime situation, is associated with a significant increase in random blood glucose values in a population of hospitalized adults. Long-term follow-up of the individuals hospitalized during these two periods can reveal differences in morbidity and mortality trends.
Evolution of a Fluctuating Population in a Randomly Switching Environment.
Wienand, Karl; Frey, Erwin; Mobilia, Mauro
2017-10-13
Environment plays a fundamental role in the competition for resources, and hence in the evolution of populations. Here, we study a well-mixed, finite population consisting of two strains competing for the limited resources provided by an environment that randomly switches between states of abundance and scarcity. Assuming that one strain grows slightly faster than the other, we consider two scenarios-one of pure resource competition, and one in which one strain provides a public good-and investigate how environmental randomness (external noise) coupled to demographic (internal) noise determines the population's fixation properties and size distribution. By analytical means and simulations, we show that these coupled sources of noise can significantly enhance the fixation probability of the slower-growing species. We also show that the population size distribution can be unimodal, bimodal, or multimodal and undergoes noise-induced transitions between these regimes when the rate of switching matches the population's growth rate.
Evolution of a Fluctuating Population in a Randomly Switching Environment
NASA Astrophysics Data System (ADS)
Wienand, Karl; Frey, Erwin; Mobilia, Mauro
2017-10-01
Environment plays a fundamental role in the competition for resources, and hence in the evolution of populations. Here, we study a well-mixed, finite population consisting of two strains competing for the limited resources provided by an environment that randomly switches between states of abundance and scarcity. Assuming that one strain grows slightly faster than the other, we consider two scenarios—one of pure resource competition, and one in which one strain provides a public good—and investigate how environmental randomness (external noise) coupled to demographic (internal) noise determines the population's fixation properties and size distribution. By analytical means and simulations, we show that these coupled sources of noise can significantly enhance the fixation probability of the slower-growing species. We also show that the population size distribution can be unimodal, bimodal, or multimodal and undergoes noise-induced transitions between these regimes when the rate of switching matches the population's growth rate.
Bergman, Martin; De, Gourab; Ganguli, Arijit; Signorovitch, James; Bao, Yanjun
2015-01-01
To compare income growth over time between employees with RA treated with anti-TNFs and those treated with methotrexate (MTX). Privately insured employees (aged ≥18) with ≥1 RA diagnosis (ICD-9: 714.0) were identified from a large-scale US employer claims database (1998-2011). Patients were stratified into treatment groups (anti-TNF-treated patients and MTX-monotherapy patients) based on their treatment history. The anti-TNF-treated patients comprised patients who filled ≥1 prescription for anti-TNFs, with or without MTX (index date defined as the date of the first anti-TNF prescription). The MTX-treated patients comprised patients who filled ≥1 prescription for MTX-monotherapy (index date randomly selected). The primary study outcome was the annual income growth rate (US dollars). Patients were followed from their index date to health plan disenrollment or the end of data availability (maximum follow-up of 5 years). The effect of treatment type on income growth was assessed using a multivariable generalized estimating equation model, adjusting for key baseline characteristics. Income growth was compared to that of the general employed population using Social Security data (1998-2011). The regression-adjusted annual growth rate in income for anti-TNF-treated patients (n = 1848) was 2.8% (CI = 1.9-3.6%), significantly greater (p < 0.05) than the 0.6% (CI = -0.2-1.4%) for MTX-monotherapy patients (n = 1866). Compared to the general employed population, income growth was lower (p < 0.05) for MTX-monotherapy patients and comparable for anti-TNF-treated patients. Compared to MTX-monotherapy, anti-TNF treatment is associated with a higher income growth rate among employees with RA. Anti-TNF-treated patients experienced comparable income growth to the general employed population norm.
Lam, Cindy Lo Kuen; Guo, Vivian Yawei; Wong, Carlos King Ho; Yu, Esther Yee Tak; Fung, Colman Siu Cheung
2017-06-01
To assess health-related quality of life (HRQOL) among Chinese adults from low-income households in Hong Kong, and to explore any threshold of household income that impaired HRQOL. A cross-sectional analysis was conducted on 298 adults from low-income families when they enrolled into a cohort study between 2012 and 2014. HRQOL was measured by the 12-item Short-Form Health Survey-version 2 (SF-12v2). Their mean SF-12v2 subscale and summary scores were compared with those of 596 age-sex-matched subjects randomly selected from a database of 2763 adults from the Hong Kong general population (ratio = 1:2). Multiple linear regressions were conducted to determine any association between monthly household income and HRQOL. Subjects from low-income households had significantly lower SF-12v2 bodily pain, general health, vitality and physical component summary (PCS) scores than the age-sex matched subjects from the general population. Subgroup analysis showed that a household income <50% of the median monthly household income in Hong Kong (HK$10 000 ≈ US$1290, i.e. poverty line in Hong Kong) was independently associated with poorer PCS and mental component summary (MCS) scores after adjustment for socio-demographics and co-morbidities. Chinese adults from low-income households had poorer HRQOL, and <50% of the median monthly household income seems to be the threshold for impairment of both physical and mental HRQOL. The findings support the current definition of the poverty line. © The Author 2016. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Skovgaard, A M; Olsen, E M; Christiansen, E; Houmann, T; Landorph, S L; Jørgensen, T
2008-05-01
Epidemiological studies of mental health problems in the first years of life are few. This study aims to investigate infancy predictors of psychopathology in the second year of life. A random general population sample of 210 children from the Copenhagen Child Birth Cohort CCC 2000 was investigated by data from National Danish registers and data collected prospectively from birth in a general child health surveillance programme. Mental health outcome at 1(1/2) years was assessed by clinical and standardised measures including the Child Behavior Check List 1(1/2)-5 (CBCL 1(1/2)-5), Infant Toddler Symptom Check List (ITSCL), Checklist for Autism in Toddlers (CHAT), Bayley Scales of Infant Development (BSID II), Mannheim Eltern Interview (MEI), Parent Child Early Relational Assessment (PC ERA) and Parent Infant Relationship Global Assessment Scale (PIR-GAS), and disordered children were diagnosed according to the International Classification of Diseases (ICD-10) and Diagnostic Classification Zero to Three (DC: 0-3). Deviant language development in the first 10 months of life predicted the child having any disorder at 1(1/2) years, OR 3.3 (1.4-8.0). Neuro-developmental disorders were predicted by deviant neuro-cognitive functioning, OR 6.8 (2.2-21.4), deviant language development, OR 5.9 (1.9-18.7) and impaired social interaction and communication, OR 3.8 (1.3-11.4). Unwanted pregnancy and parents' negative expectations of the child recorded in the first months of the child's life were significant predictors of relationship disturbances at 1(1/2) years. Predictors of neuro-developmental disorders and parent-child relationship disturbances can be identified in the first 10 months of life in children from the general population.
Frequency of RNA–RNA interaction in a model of the RNA World
STRIGGLES, JOHN C.; MARTIN, MATTHEW B.; SCHMIDT, FRANCIS J.
2006-01-01
The RNA World model for prebiotic evolution posits the selection of catalytic/template RNAs from random populations. The mechanisms by which these random populations could be generated de novo are unclear. Non-enzymatic and RNA-catalyzed nucleic acid polymerizations are poorly processive, which means that the resulting short-chain RNA population could contain only limited diversity. Nonreciprocal recombination of smaller RNAs provides an alternative mechanism for the assembly of larger species with concomitantly greater structural diversity; however, the frequency of any specific recombination event in a random RNA population is limited by the low probability of an encounter between any two given molecules. This low probability could be overcome if the molecules capable of productive recombination were redundant, with many nonhomologous but functionally equivalent RNAs being present in a random population. Here we report fluctuation experiments to estimate the redundancy of the set of RNAs in a population of random sequences that are capable of non-Watson-Crick interaction with another RNA. Parallel SELEX experiments showed that at least one in 106 random 20-mers binds to the P5.1 stem–loop of Bacillus subtilis RNase P RNA with affinities equal to that of its naturally occurring partner. This high frequency predicts that a single RNA in an RNA World would encounter multiple interacting RNAs within its lifetime, supporting recombination as a plausible mechanism for prebiotic RNA evolution. The large number of equivalent species implies that the selection of any single interacting species in the RNA World would be a contingent event, i.e., one resulting from historical accident. PMID:16495233
Beary, M D; Lacey, J H; Crutchfield, M B; Bhat, A V
1984-01-01
Taking a population of women most of whom were about to seek medication from their general practitioner for stress-induced insomnia, this sleep laboratory study examined--both electro -physiologically and psychologically--the immediate impact of temazepam, at normal prescribed dosage, on sleep. The study was double-blind, controlled with random allocation. Temazepam 20 mg, prepared as a liquid in a soft gelatin capsule, reduced sleep latency and prolonged total sleep time. A reduction in stage shifts to Stages I and II and a reduction in time spent in Stages 0 + I suggest more restful sleep. The sleep "architecture" (including REM/NREM cycling, total SWS and REM time) was relatively undisturbed. Temazepam would seem to be effective as a first-line hypnotic for short-term use in stressed patients.
Khil, Laura; Pfaffenrath, Volker; Straube, Andreas; Evers, Stefan; Berger, Klaus
2012-03-01
Unlike the prevalence, the incidence of headache disorders has attracted only little attention in epidemiological research. Different definitions of the 'population at risk' among the few published migraine and tension-type headache incidence studies limit their comparability and warrant further research. Therefore, we analysed data from the German Migraine and Headache Society (DMKG). Incidences were assessed in the general population in Germany via standardized headache questions using the International Classification of Headache Disorders, 2nd Edition (ICHD-2). The population was drawn from a 5-year age-group- stratified and gender-stratified random sample from the population register. Of the 1312 baseline participants examined between 2003 and 2004, 1122 (85.5%) participated in the follow-up in 2006 and were the basis for three different populations at risk. We found that the three populations differed in size, age, gender and incidence estimate. The total sample incidence of migraine ranged between 0% and 3.3% and of tension-type headache between 5.3% and 9.2% depending on the definition of 'at risk'. We concluded that one significant problem in headache incidence estimation is the definition of 'at risk', limiting comparability. Thus, this study supports the need for a common definition for prospective headache incidence estimations.
Wildhaber, Mark L.; Albers, Janice; Green, Nicholas; Moran, Edward H.
2017-01-01
We develop a fully-stochasticized, age-structured population model suitable for population viability analysis (PVA) of fish and demonstrate its use with the endangered pallid sturgeon (Scaphirhynchus albus) of the Lower Missouri River as an example. The model incorporates three levels of variance: parameter variance (uncertainty about the value of a parameter itself) applied at the iteration level, temporal variance (uncertainty caused by random environmental fluctuations over time) applied at the time-step level, and implicit individual variance (uncertainty caused by differences between individuals) applied within the time-step level. We found that population dynamics were most sensitive to survival rates, particularly age-2+ survival, and to fecundity-at-length. The inclusion of variance (unpartitioned or partitioned), stocking, or both generally decreased the influence of individual parameters on population growth rate. The partitioning of variance into parameter and temporal components had a strong influence on the importance of individual parameters, uncertainty of model predictions, and quasiextinction risk (i.e., pallid sturgeon population size falling below 50 age-1+ individuals). Our findings show that appropriately applying variance in PVA is important when evaluating the relative importance of parameters, and reinforce the need for better and more precise estimates of crucial life-history parameters for pallid sturgeon.
EQ-5D Portuguese population norms.
Ferreira, Lara Noronha; Ferreira, Pedro L; Pereira, Luis N; Oppe, Mark
2014-03-01
The EQ-5D is a widely used preference-based measure. Normative data can be used as references to analyze the effects of healthcare, determine the burden of disease and enable regional or country comparisons. Population norms for the EQ-5D exist for other countries but have not been previously published for Portugal. The purpose of this study was to derive EQ-5D Portuguese population norms. The EQ-5D was applied by phone interview to a random sample of the Portuguese general population (n = 1,500) stratified by age, gender and region. The Portuguese value set was used to derive the EQ-5D index. Mean values were computed by gender and age groups, marital status, educational attainment, region and other variables to obtain the EQ-5D Portuguese norms. Health status declines with advancing age, and women reported worse health status than men. These results are similar to other EQ-5D population health studies. This study provides Portuguese population health-related quality of life data measured by the EQ-5D that can be used as population norms. These norms can be used to inform Portuguese policy makers, health care professionals and researchers in issues related to health care policy and planning and quantification of treatment effects on health status.
Krogh, Jesper; Petersen, Lone; Timmermann, Michael; Saltin, Bengt; Nordentoft, Merete
2007-01-01
In western countries, the yearly incidence of depression is estimated to be 3-5% and the lifetime prevalence is 17%. In patient populations with chronic diseases the point prevalence may be 20%. Depression is associated with increased risk for various conditions such as osteoporoses, cardiovascular diseases, and dementia. WHO stated in 2000 that depression was the fourth leading cause of disease burden in terms of disability. In 2000 the cost of depression in the US was estimated to 83 billion dollars. A predominance of trials suggests that physical exercise has a positive effect on depressive symptoms. However, a meta-analysis from 2001 stated: "The effectiveness of exercise in reducing symptoms of depression cannot be determined because of a lack of good quality research on clinical populations with adequate follow-up." The major objective for this randomized trial is to compare the effect of non-aerobic, aerobic, and relaxation training on depressive symptoms using the blindly assessed Hamilton depression scale (HAM-D(17)) as primary outcome. The secondary outcome is the effect of the intervention on working status (i.e., lost days from work, employed/unemployed) and the tertiary outcomes consist of biological responses. The trial is designed as a randomized, parallel-group, observer-blinded clinical trial. Patients are recruited through general practitioners and psychiatrist and randomized to three different interventions: 1) non-aerobic, -- progressive resistance training, 2) aerobic training, -- cardio respiratory fitness, and 3) relaxation training with minimal impact on strength or cardio respiratory fitness. Training for all three groups takes place twice a week for 4 months. Evaluation of patients' symptoms takes place four and 12 months after inclusion. The trial is designed to include 45 patients in each group. Statistical analysis will be done as intention to treat (all randomized patients). Results from the DEMO trial will be reported according to the CONSORT guidelines in 2008-2009.
Pujades-Rodriguez, Mar; Guttmann, Oliver P; Gonzalez-Izquierdo, Arturo; Duyx, Bram; O'Mahony, Constantinos; Elliott, Perry; Hemingway, Harry
2018-01-01
To evaluate unmet clinical need in unselected hypertrophic cardiomyopathy (HCM) patients to determine the risk of a wide range of subsequent cardiovascular disease endpoints and safety endpoints relevant for trial design. Population based cohort (CALIBER, linked primary care, hospital and mortality records in England, period 1997-2010), all people diagnosed with HCM were identified and matched by age, sex and general practice with ten randomly selected people without HCM. Random-effects Poisson models were used to assess the associations between HCM and cardiovascular diseases and bleeding. Among 3,290,455 eligible people a diagnosis of hypertrophic cardiomyopathy was found in 4 per 10,000. Forty-one percent of the 1,160 individuals with hypertrophic cardiomyopathy were women and the median age was 57 years. The median follow-up was 4.0 years. Compared to general population controls, people with HCM had higher risk of ventricular arrhythmia (incidence rate ratio = 23.53, [95% confidence interval 12.67-43.72]), cardiac arrest or sudden cardiac death (6.33 [3.69-10.85]), heart failure (4.31, [3.30-5.62]), and atrial fibrillation (3.80 [3.04-4.75]). HCM was also associated with a higher incidence of myocardial infarction ([MI] 1.90 [1.27-2.84]) and coronary revascularisation (2.32 [1.46-3.69]).The absolute Kaplan-Meier risks at 3 years were 8.8% for the composite endpoint of cardiovascular death or heart failure, 8.4% for the composite of cardiovascular death, stroke or myocardial infarction, and 1.5% for major bleeding. Our study identified major unmet need in HCM and highlighted the importance of implementing improved cardiovascular prevention strategies to increase life-expectancy of the contemporary HCM population. They also show that national electronic health records provide an effective method for identifying outcomes and clinically relevant estimates of composite efficacy and safety endpoints essential for trial design in rare diseases.
Baili, Paolo; Di Salvo, Francesca; de Lorenzo, Francesco; Maietta, Francesco; Pinto, Carmine; Rizzotto, Vera; Vicentini, Massimo; Rossi, Paolo Giorgi; Tumino, Rosario; Rollo, Patrizia Concetta; Tagliabue, Giovanna; Contiero, Paolo; Candela, Pina; Scuderi, Tiziana; Iannelli, Elisabetta; Cascinu, Stefano; Aurora, Fulvio; Agresti, Roberto; Turco, Alberto; Sant, Milena; Meneghini, Elisabetta; Micheli, Andrea
2016-05-01
To illustrate the out-of-pocket (OOP) costs incurred by a population-based group of patients from 5 to 10 years since their cancer diagnosis in a country with a nationwide public health system. Interviews on OOP costs to a sample of 5-10 year prevalent cases randomly extracted from four population-based cancer registries (CRs), two in the north and two in the south of Italy. The patients' general practitioners (GPs) gave assurance about the patient's physical and psychological condition for the interview. A zero-inflated negative binomial model was used to analyze OOP cost determinants. Two hundred six cancer patients were interviewed (48 % of the original sample). On average, a patient in the north spent €69 monthly, against €244 in the south. The main differences are for transport, room, and board (TRB) to reach the hospital and/or the cancer specialist (north €0; south €119). Everywhere, OOP costs without TRB costs were higher for patients with a low quality of life. Despite the limited participation, our study sample's characteristics are similar to those of the Italian cancer prevalence population, allowing us to generalize the results. The higher OOP costs in the south may be due to the scarcity of oncologic structures, obliging patients to seek assistance far from their residence. Implications for cancer survivors Cancer survivors need descriptive studies to show realistic data about their status. Future Italian and European descriptive studies on cancer survivorship should be based on population CRs and involve GPs in order to approach the patient at best.
Alavian, Seyed Moayed; Tabatabaei, Seyed Vahid; Ghadimi, Teyyeb; Beedrapour, Farzam; Kafi-abad, Sedigheh Amini; Gharehbaghian, Ahmad; Abolghasemi, Hassan
2012-01-01
Introduction: Hepatitis B virus (HBV) infection is a serious global public health problem affecting billions of people globally. The lack of information of its seroprevalence among the general population is an obstacle for formulating effective policies to reduce the burden viral hepatitis. Therefore, this population based serological survey was conducted in Kurdistan province, where no epidemiological data was available to determine the prevalence and risk factors of HBV infection. Methods: 1613 healthy subjects were selected from all districts of Kurdistan province (in the western of Iran) using random cluster sampling. The subjects’ age ranged from 6 to 65 years old. Serum samples were tested for HBcAb, HBsAg and anti-HDV antibody. Screening tests were carried out by the third generation of ELISA. Various risk factors were recorded and multivariate analysis was performed. Results: The prevalence of HBsAg and HBcAb in Kurdistan was before 0.80% (95% CI 0.44; 1.34) and 5.02% (95% CI 4.03; 6.17), respectively. None of HBsAg carriers had positive anti-HDV antibody. Predictors of HBsAg or HBcAb in multivariate analysis were: older age and marriage. We did not find any significant differences between males and females. Conclusion: Our population based study suggests that intrafamilial HBV transmission plays a major role in HBV transmission in Kurdistan province. Furthermore, approximately 5% of general population in this province has prior exposure to HBV and less than 1% is HBsAg carriers. However, we could not find any case of HDV infection among them. PMID:23189228
Fatigue in young survivors of extracranial childhood cancer: a Finnish nationwide survey.
Mört, Susanna; Lähteenmäki, Päivi M; Matomäki, Jaakko; Salmi, Toivo T; Salanterä, Sanna
2011-11-01
To evaluate self-reports of fatigue by young cancer survivors (aged 11-18 years), to compare young survivors' fatigue scores with the scores of a healthy control group and of the parent proxy evaluation, and to analyze whether demographic or disease-related factors are associated with young survivors' fatigue. Cross-sectional quantitative study. An urban hospital in southwestern Finland. 384 survivors diagnosed with an extracranial malignancy at age 16 or younger, who have survived four or more years postdiagnosis, and who are free of cancer. General matched population controls were randomly selected from the Finnish Population Registry. Demographic data and a self-report written fatigue questionnaire. Total fatigue (TF), general fatigue (GF), sleep or rest fatigue (SF), and cognitive fatigue. The control populations reported significantly more issues with TF, GF, and SF than did the survivor population. In survivors, older age, the need for remedial education at school, and a sarcoma diagnosis were associated with increasing fatigue, whereas female gender, better school grades, and greater health-related quality-of-life (HRQOL) scores were associated with lower fatigue. The study variables explained 49%-65% of the variation in fatigue scores. Although survivors and their matched controls seem to have similar fatigue, subgroups of survivors do experience excessive fatigue, which may have an impact on their HRQOL. This study increases the knowledge about fatigue levels of young survivors of extracranial malignancies and identifies the need for instruments specifically designed to assess fatigue in this population. The healthcare team should pay attention to the fatigue level of young survivors, particularly SF.
Leprosy incidence: six years follow-up of a population cohort in Bangladesh.
Basel, Prem; Pahan, David; Moet, Fake J; Oskam, Linda; Richardus, Jan Hendrik
2014-09-01
With approximately 250,000 new leprosy cases detected annually, transmission of M. leprae appears to be ongoing in many areas of the world. By studying prospectively the number of leprosy patients found in a population sample at the beginning of the study (prevalence) and the number of new patients found during the 6-year observation period (incidence), we aim to understand better the transmission of M. leprae and the burden of disease. To establish the prevalence and incidence rates of leprosy in the general population of a high endemic area in Bangladesh, we followed prospectively 20,218 individuals from a random cluster sample of the population and examined them at 2-yearly intervals for 6 years. At intake we found 27 new leprosy cases, indicating a prevalence of previously undiagnosed leprosy of 13.3/10,000. Follow-up at 2, 4 and 6 years revealed 17, 16, and eight new cases, respectively, representing incidence rates of 4.0, 4.5 and 2.3/10,000 PYAR, respectively. The incidence rate over 6 years was 3.7/10,000 PYAR. The observed incidence rate is three times higher than the new case detection rate in the same area. Of all 68 new leprosy cases, five (7%) had MB leprosy. The proportion of children under 15 years was 24%. The proportion of female patients was 60%, but the incidence rate of leprosy was the same for males and females. The decline in incidence of leprosy in a general population sample is less pronounced than routine data from a control programme led us to expect.
Prevalence of fragrance sensitivity in the American population.
Caress, Stanley M; Steinemann, Anne C
2009-03-01
This study determined the percentages of individuals who report adverse effects from exposure to fragranced products in the U.S. population and in subpopulations of those with asthma or chemical sensitivity. Data were collected through telephone interviews from two geographically weighted, random samples of the continental U.S. in two surveys during 2002-2003 and 2005-2006 (1,057 and 1,058 cases, respectively). Respondents were asked if they find being next to someone wearing a scented product irritating or appealing; if they have headaches, breathing difficulties, or other problems when exposed to air fresheners or deodorizers; and if they are irritated by the scent from laundry products, fabric softeners, or dryer sheets that are vented outside. Results aggregated from both surveys found that 30.5% of the general population reported scented products on others irritating, 19% reported adverse health effects from air fresheners, and 10.9% reported irritation by scented laundry products vented outside. This study reveals that a considerable percentage of the U.S. population reports adverse health effects or irritation from fragranced products, with higher percentages among those with asthma and chemical sensitivity.
Evolutionary dynamics on graphs
NASA Astrophysics Data System (ADS)
Lieberman, Erez; Hauert, Christoph; Nowak, Martin A.
2005-01-01
Evolutionary dynamics have been traditionally studied in the context of homogeneous or spatially extended populations. Here we generalize population structure by arranging individuals on a graph. Each vertex represents an individual. The weighted edges denote reproductive rates which govern how often individuals place offspring into adjacent vertices. The homogeneous population, described by the Moran process, is the special case of a fully connected graph with evenly weighted edges. Spatial structures are described by graphs where vertices are connected with their nearest neighbours. We also explore evolution on random and scale-free networks. We determine the fixation probability of mutants, and characterize those graphs for which fixation behaviour is identical to that of a homogeneous population. Furthermore, some graphs act as suppressors and others as amplifiers of selection. It is even possible to find graphs that guarantee the fixation of any advantageous mutant. We also study frequency-dependent selection and show that the outcome of evolutionary games can depend entirely on the structure of the underlying graph. Evolutionary graph theory has many fascinating applications ranging from ecology to multi-cellular organization and economics.
Stockdale, Alexander J; Chaponda, Mas; Beloukas, Apostolos; Phillips, Richard Odame; Matthews, Philippa C; Papadimitropoulos, Athanasios; King, Simon; Bonnett, Laura; Geretti, Anna Maria
2017-10-01
Hepatitis D virus (also known as hepatitis delta virus) can establish a persistent infection in people with chronic hepatitis B, leading to accelerated progression of liver disease. In sub-Saharan Africa, where HBsAg prevalence is higher than 8%, hepatitis D virus might represent an important additive cause of chronic liver disease. We aimed to establish the prevalence of hepatitis D virus among HBsAg-positive populations in sub-Saharan Africa. We systematically reviewed studies of hepatitis D virus prevalence among HBsAg-positive populations in sub-Saharan Africa. We searched PubMed, Embase, and Scopus for papers published between Jan 1, 1995, and Aug 30, 2016, in which patient selection criteria and geographical setting were described. Search strings included sub-Saharan Africa, the countries therein, and permutations of hepatitis D virus. Cohort data were also added from HIV-positive populations in Malawi and Ghana. Populations undergoing assessment in liver disease clinics and those sampled from other populations (defined as general populations) were analysed. We did a meta-analysis with a DerSimonian-Laird random-effects model to calculate a pooled estimate of hepatitis D virus seroprevalence. Of 374 studies identified by our search, 30 were included in our study, only eight of which included detection of hepatitis D virus RNA among anti-hepatitis D virus seropositive participants. In west Africa, the pooled seroprevalence of hepatitis D virus was 7·33% (95% CI 3·55-12·20) in general populations and 9·57% (2·31-20·43) in liver-disease populations. In central Africa, seroprevalence was 25·64% (12·09-42·00) in general populations and 37·77% (12·13-67·54) in liver-disease populations. In east and southern Africa, seroprevalence was 0·05% (0·00-1·78) in general populations. The odds ratio for anti-hepatitis D virus detection among HBsAg-positive patients with liver fibrosis or hepatocellular carcinoma was 5·24 (95% CI 2·74-10·01; p<0·0001) relative to asymptomatic controls. Findings suggest localised clusters of hepatitis D virus endemicity across sub-Saharan Africa. Epidemiological data are needed from southern and east Africa, and from patients with established liver disease. Further studies should aim to define the reliability of hepatitis D virus testing methods, identify risk factors for transmission, and characterise the natural history of the infection in the region. Wellcome Trust, Royal Society. Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.
Generalizability of carry-over effects in the emotional Stroop task.
Waters, Andrew J; Sayette, Michael A; Franken, Ingmar H A; Schwartz, Joseph E
2005-06-01
The emotional Stroop task has been the most widely used task to examine attentional bias to emotionally salient stimuli. In one format of this task, words are presented to participants in a mixed randomized or quasi-randomized sequence. Using a mixed smoking Stroop task, we have previously demonstrated that smokers are slower to respond to words which follow smoking-related words than words which follow neutral words. Here we show that this carry-over effect is present in heroin addicts-but not control subjects-in a heroin Stroop task, and in normal subjects in a stress Stroop task. Thus, the effect generalizes to other populations. In addition, an examination of the studies that have collected data from both mixed and blocked formats provides converging evidence for the presence of carry-over effects. We discuss the implications of the carry-over effect for research using the emotional Stroop task.
Please don't misuse the museum: 'declines' may be statistical.
Campbell Grant, Evan H
2015-03-01
Detecting declines in populations at broad spatial scales takes enormous effort, and long-term data are often more sparse than is desired for estimating trends, identifying drivers for population changes, framing conservation decisions, or taking management actions. Museum records and historic data can be available at large scales across multiple decades, and are therefore an attractive source of information on the comparative status of populations. However, changes in populations may be real (e.g. in response to environmental covariates) or resulting from variation in our ability to observe the true population response (also possibly related to environmental covariates). This is a (statistical) nuisance in understanding the true status of a population. Evaluating statistical hypotheses alongside more interesting ecological ones is important in the appropriate use of museum data. Two statistical considerations are generally applicable to use of museum records: first without initial random sampling, comparison with contemporary results cannot provide inference to the entire range of a species, and second the availability of only some individuals in a population may respond to environmental changes. Changes in the availability of individuals may reduce the proportion of the population that is present and able to be counted on a given survey event, resulting in an apparent decline even when population size is stable. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Lindblad, Robert; Hu, Lian; Oden, Neal; Wakim, Paul; Rosa, Carmen; VanVeldhuisen, Paul
2016-11-01
Most substance use disorders (SUD) treatment clinical trials are too short and small to reliably estimate the incidence of rare events like death. The aim of this study is to estimate the overall mortality rates among a SUD treatment-seeking population by pooling participants from multiple clinical trials conducted through the National Institute on Drug Abuse (NIDA)-sponsored National Drug Abuse Treatment Clinical Trials Network (CTN). Drug and or alcohol users (N=9866) who sought treatment and participated in one of the twenty-two CTN trials. Data were collected through randomized clinical trials in national community treatment programs for SUD. Pooled analysis was performed to assess age- and gender-standardized mortality rate(s) (SM rate(s)), and mortality ratio(s) (SM ratio(s)) of CTN trial participants compared to the U.S. general population. The age- and gender-SM rate among CTN trials participants was 1403 (95% CI: 862-2074) per 100,000 person years (PY) compared to 542 (95% CI: 541-543) per 100,000 PY among the U.S. general population in 2005. By gender, age-adjusted SM ratio for female CTN trial participants was over five times (SM ratio=5.35, 95% CI: 3.31-8.19)), and for male CTN trial participants, it was over three times (SM ratio=3.39, 95% CI: 2.25-4.90) higher than their gender comparable peers in the U.S. general population. Age and gender-standardized mortality rates and ratios among NIDA CTN SUD treatment-seeking clinical trial participants are higher than the age and gender comparable U.S. general population. The overall mortality rates of CTN trial participants are similar to in-treatment mortality reported in large U.S. and non-U.S. cohorts of opioid users. Future analysis with additional CTN trial participants and risk times will improve the stability of estimates, especially within subgroups based on primary substance of abuse. These SUD mortality rates can be used to facilitate safety monitoring within SUD clinical trials. Copyright © 2016 Elsevier Inc. All rights reserved.
Trétarre, B; Bourgarel, S; Stoebner-Delbarre, A; Jacot, W; Bessaoud, F; Satge, D
2017-03-01
We aimed to describe, among a population of women with intellectual disabilities (ID) living in institutions in France, the characteristics in whom breast cancer (BC) was diagnosed and of those who participated in BC screening. Study was performed in 2009 among a random, representative sample of women with ID living in institutions in France. Participants answered a questionnaire either directly by themselves, or with the help of an intermediary. In total, 978 women with ID aged over 18 years were included, and 14 were diagnosed with BC. The incidence observed in this sample of women with ID is similar to that of the general population (standardised incidence ratio, SIR 0.857, 95% confidence interval (CI) 0.42-1.53). Average age at diagnosis was 47.8 years, and the risk of developing BC before the age of 50 was 2.03% (0.4-3.66). This risk was not significantly different from that of the general population (2.4%, 1.0-3.78). Obesity was almost twice as frequent in women who had BC as compared to those without BC (43% vs. 22.5%, P = 0.0196). Among the 310 women aged >50 years and eligible for the national BC screening programme, 238 (77%) had already had at least one mammogram, and 199 had had it within the previous 2 years. Adherence to the screening programme was 64.2% (199/310) in the participating institutions. This rate was slightly higher than the national average of 62% for the same period. The results of this study show that BC is equally as frequent among women with ID living in institutions as in the general population, and occurs at around the same age. Obesity was significantly more frequent among women in whom BC was diagnosed in our study. Participation in BC screening is slightly higher among women with ID living in institutions than among the general population. © 2016 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.
Kashdan, Todd B.; Farmer, Antonina S.
2014-01-01
The ability to recognize and label emotional experiences has been associated with well-being and adaptive functioning. This skill is particularly important in social situations, as emotions provide information about the state of relationships and help guide interpersonal decisions, such as whether to disclose personal information. Given the interpersonal difficulties linked to social anxiety disorder (SAD), deficient negative emotion differentiation may contribute to impairment in this population. We hypothesized that people with SAD would exhibit less negative emotion differentiation in daily life, and these differences would translate to impairment in social functioning. We recruited 43 people diagnosed with generalized SAD and 43 healthy adults to describe the emotions they experienced over 14 days. Participants received palmtop computers for responding to random prompts and describing naturalistic social interactions; to complete end-of-day diary entries, they used a secure online website. We calculated intraclass correlation coefficients to capture the degree of differentiation of negative and positive emotions for each context (random moments, face-to-face social interactions, and end-of-day reflections). Compared to healthy controls, the SAD group exhibited less negative (but not positive) emotion differentiation during random prompts, social interactions, and (at trend level) end-of-day assessments. These differences could not be explained by emotion intensity or variability over the 14 days, or to comorbid depression or anxiety disorders. Our findings suggest that people with generalized SAD have deficits in clarifying specific negative emotions felt at a given point of time. These deficits may contribute to difficulties with effective emotion regulation and healthy social relationship functioning. PMID:24512246
Hull, Mark W; Salters, Kate; Samji, Hasina; Cescon, Angela; Sereda, Paul; Lima, Viviane D; Nosyk, Bohdan; Whitehurst, David G T; Lear, Scott A; Montaner, Julio S G; Hogg, Robert S
2018-01-01
Purpose The Comparative Outcomes And Service Utilization Trends (COAST) Study in British Columbia (BC), Canada, was designed to evaluate the determinants of health outcomes and health care services use among people living with HIV (PLHIV) as they age in the period following the introduction of combination antiretroviral therapy (cART). The study also assesses how age-associated comorbidities and health care use among PLHIV may differ from those observed in the general population. Participants COAST was established through a data linkage between two provincial data sources: The BC Centre for Excellence in HIV/AIDS Drug Treatment Program, which centrally manages cART dispensation across BC and contains prospectively collected data on demographic, immunological, virological, cART use and other clinical information for all known PLHIV in BC; and Population Data BC, a provincial data repository that holds individual event-level, longitudinal data for all 4.6 million BC residents. COAST participants include 13 907 HIV-positive adults (≥19 years of age) and a 10% random sample inclusive of 516 340 adults from the general population followed from 1996 to 2013. Findings to date For all participants, linked individual-level data include information on demographics, health service use (eg, inpatient care, outpatient care and prescription medication dispensations), mortality, and HIV diagnostic and clinical data. Publications from COAST have demonstrated the significant mortality reductions and dramatic changes in the causes of death among PLHIV from 1996 to 2012, differences in the amount of time spent in a healthy state by HIV status, and high levels of injury and mood disorder diagnosis among PLHIV compared with the general population. Future plans To capture the dynamic nature of population health parameters, regular data updates and a refresh of the data linkage are planned to occur every 2 years, providing the basis for planned analysis to examine age-associated comorbidities and patterns of health service use over time. PMID:29331972
Stenhagen, Magnus; Nordell, Eva; Elmståhl, Sölve
2013-04-01
The aim of this study was to describe the prevalence of falls in a general older population, especially among the most elderly, and the risk markers associated with falls. This is a cross-sectional study in which 38 fall risk markers were analysed in non-, occasional- and frequent-fallers. The population was 2,865 individuals (aged 60-93), randomly selected from the general population register. The risk of falling was calculated as age-adjusted odds ratios. The relation between the number of risk markers for an individual and falls was also analysed. About one in ten reported falling during the past 6 months, 35% of which were over 90 years old. Twenty-one risk markers were significantly related to falls confirming falling as a multifactorial problem. These included a variety of diseases, symptoms, medical and physical functions, life-style factors and the taking of certain drugs. The five risk markers with the highest odds ratio in frequent fallers were 'tendency to fall' (37.9), 'low walking speed' (12.8), consumption of 'neuroleptics' (10.9), 'impaired mobility' (10.0) and 'dementia' (5.4). Subjects with more than four and seven risk markers showed a 9- respectively 28-fold increase in the risk of falling, especially among frequent fallers and those aged over 90 years. Falls are common in the elderly population and the risk is multifactorial. The results imply that there is an overrepresentation of fallers in a distinct subgroup of the very elderly and those with multiple risk markers. The self-perceived clinical sign 'tendency to fall' seems highly sensitive as indicator of individuals at risk. Several risk markers may be treatable. Fall risk seems to increase in a non-linear, almost exponential way with increasing number of risk markers.
Bouthoorn, Selma; Gohar, Aisha; Valstar, Gideon; den Ruijter, Hester M; Reitsma, J B; Hoes, Arno W; Rutten, Frans H
2018-04-18
Type 2 diabetes mellitus (T2D) is associated with the development of left ventricular systolic dysfunction (LVSD) and heart failure with reduced ejection fraction (HFrEF). T2D patients with LVSD are at higher risk of mortality and morbidity than patients without LVSD, while progression of LVSD can be delayed or halted by the use of proven therapies. As estimates of the prevalence are scarce and vary considerably, the aim of this study was to retrieve summary estimates of the prevalence of LVSD/HFrEF in T2D and to see if there were any sex differences. A systematic search of Medline and Embase was performed to extract the prevalence of LVSD/HFrEF in T2D (17 studies, mean age 50.1 ± 6.3 to 71.5 ± 7.5), which were pooled using random-effects meta-analysis. The pooled prevalence of LVSD was higher in hospital populations (13 studies, n = 5835, 18% [95% CI 17-19%]), than in the general population (4 studies, n = 1707, 2% [95% CI 2-3%]). Seven studies in total reported sex-stratified prevalence estimates (men: 7% [95% CI 5-8%] vs. women: 1.3% [95% CI 0.0.2.2%]). The prevalence of HFrEF was available in one general population study (5.8% [95% CI 3.7.6%], men: 6.8% vs. women: 3.0%). The summary prevalence of LVSD is higher among T2D patients from a hospital setting compared with from the general population, with a higher prevalence in men than in women in both settings. The prevalence of HFrEF among T2D in the population was only assessed in a single study and again was higher among men than women.
Howard, Virginia J; McClure, Leslie A; Meschia, James F; Pulley, Leavonne; Orr, Sean C; Friday, Gary H
2006-10-09
A substantial portion of the general population has clinically silent stroke on brain imaging. These lesions may cause symptoms. This study assessed the prevalence of stroke symptoms in a stroke- and transient ischemic attack (TIA)-free population and the association of symptoms with risk factors indexed by the Framingham Stroke Risk Score. We performed a cross-sectional analysis from a randomly sampled national cohort enrolled from January 25, 2003, through November 30, 2005, with oversampling from the southeastern stroke belt and African American populations. The main outcome measure was stroke symptoms assessed by validated questionnaire. The study included 18 462 (41% African American; 51% female; mean age, 65.8 years) participants who reported no stroke or TIA. The prevalence of stroke symptoms was 5.8% for sudden painless hemibody weakness, 8.5% for sudden hemibody numbness, 4.6% for sudden painless loss of vision in one or both eyes, 3.1% for sudden hemifield visual loss, 2.7% for sudden inability to understand speech, and 3.8% for sudden inability of linguistic expression. The prevalence of 1 or more symptoms was 17.8%. Relative to the first quartile of the Framingham Stroke Risk Score, the adjusted odds ratio for 1 or more stroke symptoms increased from 1.0 (95% confidence interval [CI], 0.90-1.2) in the second quartile to 1.2 (95% CI, 1.1-1.5) and 1.5 (95% CI, 1.3-1.6) in successive quartiles. Symptoms were more prevalent among African American compared with white participants and among those with lower income, lower educational level, and fair to poor perceived health status. The general population without prior diagnosed stroke or TIA has a high prevalence of stroke symptoms. The relationship between symptoms and risk factors suggests that some symptomatic individuals may have had clinically undetected cerebrovascular events and may benefit from aggressive stroke prophylaxis.
Juul-Kristensen, Birgit; Østengaard, Lasse; Hansen, Sebrina; Boyle, Eleanor; Junge, Tina; Hestbaek, Lise
2017-05-30
Generalised Joint Hypermobility (GJH) is a hereditary condition with an ability to exceed the joints beyond the normal range. The prevalence of GJH in the adult population and its impact on upper body musculoskeletal health and quality of life has mostly been studied in selected populations. The aims of this study were therefore, firstly to study the prevalence of GJH and GJH including shoulder hypermobility (GJHS), in the general Danish adult population; secondly to test the associations between GJH or GJHS and upper body musculoskeletal symptoms and health-related quality of life (HRQoL). The study was cross-sectional where 2072 participants, aged 25-65, randomly extracted from the Danish Civil Registration System), were invited to answer a questionnaire battery (Five-Part Questionnaire for classification of GJH, Standardised Nordic Questionnaire for musculoskeletal symptoms, EuroQoL-5D for HRQoL). Totally 1006 (49%) participants responded. The prevalence of GJH and GJHS were 30% (n = 300) and 5% (n = 51), respectively. Compared with Non GJH (NGJH), participants with GJH and GJHS had Odds Ratio (OR) of 1.5-3.5 for upper body musculoskeletal symptoms within the last 12 months (mostly shoulders and hands/wrists). GJH and GJHS also had OR 1.6-4.4 for being prevented from usual activities, mostly due to shoulder and neck symptoms. Furthermore, GJH and GJHS had OR 2.2-3.1 for upper body musculoskeletal symptoms lasting for more than 90 days (neck, shoulders, hand/wrists), and 1.5-3.5 for reduced HRQoL (all dimensions, but anxiety/depression) compared with NGJH. Generally, most OR for GJHS were about twice as high as for those having GJH alone. GJH and GJHS are frequently self-reported musculoskeletal conditions in the Danish adult population. Compared with NGJH, GJH and especially GJHS, present with higher OR for upper body musculoskeletal symptoms, more severe symptoms and decreased HRQoL.
General Household Emergency Preparedness: A Comparison Between Veterans and Nonveterans
Der-Martirosian, Claudia; Strine, Tara; Atia, Mangwi; Chu, Karen; Mitchell, Michael N.; Dobalian, Aram
2015-01-01
Background Despite federal and local efforts to educate the public to prepare for major emergencies, many US households remain unprepared for such occurrences. United States Armed Forces veterans are at particular risk during public health emergencies as they are more likely than the general population to have multiple health conditions. Methods This study compares general levels of household emergency preparedness between veterans and nonveterans by focusing on seven surrogate measures of household emergency preparedness (a 3-day supply of food, water, and prescription medications, a battery-operated radio and flashlight, a written evacuation plan, and an expressed willingness to leave the community during a mandatory evacuation). This study used data from the 2006 through 2010 Behavioral Risk Factor Surveillance System (BRFSS), a state representative, random sample of adults aged 18 and older living in 14 states. Results The majority of veteran and nonveteran households had a 3-day supply of food (88% vs 82%, respectively) and prescription medications (95% vs 89%, respectively), access to a working, battery-operated radio (82% vs 77%, respectively) and flashlight (97% vs 95%, respectively), and were willing to leave the community during a mandatory evacuation (91% vs 96%, respectively). These populations were far less likely to have a 3-day supply of water (61% vs 52%, respectively) and a written evacuation plan (24% vs 21%, respectively). After adjusting for various sociodemographic covariates, general health status, and disability status, households with veterans were significantly more likely than households without veterans to have 3-day supplies of food, water, and prescription medications, and a written evacuation plan; less likely to indicate that they would leave their community during a mandatory evacuation; and equally likely to have a working, battery-operated radio and fiashlight. Conclusion These findings suggest that veteran households appear to be better prepared for emergencies than do nonveteran households, although the lower expressed likelihood of veterans households to evacuate when ordered to do so may place them at a somewhat greater risk of harm during such events. Further research should examine household preparedness among other vulnerable groups including subgroups of veteran populations and the reasons why their preparedness may differ from the general population. PMID:24642181
General household emergency preparedness: a comparison between veterans and nonveterans.
Der-Martirosian, Claudia; Strine, Tara; Atia, Mangwi; Chu, Karen; Mitchell, Michael N; Dobalian, Aram
2014-04-01
Despite federal and local efforts to educate the public to prepare for major emergencies, many US households remain unprepared for such occurrences. United States Armed Forces veterans are at particular risk during public health emergencies as they are more likely than the general population to have multiple health conditions. This study compares general levels of household emergency preparedness between veterans and nonveterans by focusing on seven surrogate measures of household emergency preparedness (a 3-day supply of food, water, and prescription medications, a battery-operated radio and flashlight, a written evacuation plan, and an expressed willingness to leave the community during a mandatory evacuation). This study used data from the 2006 through 2010 Behavioral Risk Factor Surveillance System (BRFSS), a state representative, random sample of adults aged 18 and older living in 14 states. The majority of veteran and nonveteran households had a 3-day supply of food (88% vs 82%, respectively) and prescription medications (95% vs 89%, respectively), access to a working, battery-operated radio (82% vs 77%, respectively) and flashlight (97% vs 95%, respectively), and were willing to leave the community during a mandatory evacuation (91% vs 96%, respectively). These populations were far less likely to have a 3-day supply of water (61% vs 52%, respectively) and a written evacuation plan (24% vs 21%, respectively). After adjusting for various sociodemographic covariates, general health status, and disability status, households with veterans were significantly more likely than households without veterans to have 3-day supplies of food, water, and prescription medications, and a written evacuation plan; less likely to indicate that they would leave their community during a mandatory evacuation; and equally likely to have a working, battery-operated radio and flashlight. These findings suggest that veteran households appear to be better prepared for emergencies than do nonveteran households, although the lower expressed likelihood of veterans households to evacuate when ordered to do so may place them at a somewhat greater risk of harm during such events. Further research should examine household preparedness among other vulnerable groups including subgroups of veteran populations and the reasons why their preparedness may differ from the general population.
Barbieri, Flavia Laura; Cournil, Amandine; Gardon, Jacques
2009-08-01
Methylmercury exposure in Amazonian communities through fish consumption has been widely documented in Brazil. There is still a lack of data in other Amazonian countries, which is why we conducted this study in the Bolivian Amazon basin. Simple random sampling was used from a small village located in the lower Beni River, where there is intense gold mining and high fish consumption. All participants were interviewed and hair samples were taken to measure total mercury concentrations. The hair mercury geometric mean in the general population was 3.02 microg/g (CI: 2.69-3.37; range: 0.42-15.65). Age and gender were not directly associated with mercury levels. Fish consumption showed a positive relation and so did occupation, especially small-scale gold mining. Hair mercury levels were lower than those found in Brazilian studies, but still higher than in non-exposed populations. It is necessary to assess mercury exposure in the Amazonian regions where data is still lacking, using a standardized indicator.
Chapman, Sandra B.; Mudar, Raksha A.
2014-01-01
Public awareness of cognitive health is fairly recent compared to physical health. Growing evidence suggests that cognitive training offers promise in augmenting cognitive brain performance in normal and clinical populations. Targeting higher-order cognitive functions, such as reasoning in particular, may promote generalized cognitive changes necessary for supporting the complexities of daily life. This data-driven perspective highlights cognitive and brain changes measured in randomized clinical trials that trained gist reasoning strategies in populations ranging from teenagers to healthy older adults, individuals with brain injury to those at-risk for Alzheimer's disease. The evidence presented across studies support the potential for Gist reasoning training to strengthen cognitive performance in trained and untrained domains and to engage more efficient communication across widespread neural networks that support higher-order cognition. The meaningful benefits of Gist training provide compelling motivation to examine optimal dose for sustained benefits as well as to explore additive benefits of meditation, physical exercise, and/or improved sleep in future studies. PMID:24808834
Slowly switching between environments facilitates reverse evolution in small populations
NASA Astrophysics Data System (ADS)
Tan, Longzhi; Gore, Jeff
2011-03-01
The rate at which a physical process occurs usually changes the behavior of a system. In thermodynamics, the reversibility of a process generally increases when it occurs at an infinitely slow rate. In biological evolution, adaptations to a new environment may be reversed by evolution in the ancestral environment. Such fluctuating environments are ubiquitous in nature, although how the rate of switching affects reverse evolution is unknown. Here we use a computational approach to quantify evolutionary reversibility as a function of the rate of switching between two environments. For small population sizes, which travel on landscapes as random walkers, we find that both genotypic and phenotypic reverse evolution increase at slow switching rates. However, slow switching of environments decreases evolutionary reversibility for a greedy walker, corresponding to large populations (extensive clonal interference). We conclude that the impact of the switching rate for biological evolution is more complicated than other common physical processes, and that a quantitative approach may yield significant insight into reverse evolution.
Ethnicity, social disadvantage and psychotic-like experiences in a healthy population based sample.
Morgan, C; Fisher, H; Hutchinson, G; Kirkbride, J; Craig, T K; Morgan, K; Dazzan, P; Boydell, J; Doody, G A; Jones, P B; Murray, R M; Leff, J; Fearon, P
2009-03-01
We sought to investigate the prevalence and social correlates of psychotic-like experiences in a general population sample of Black and White British subjects. Data were collected from randomly selected community control subjects, recruited as part of the AESOP study, a three-centre population based study of first-episode psychosis. The proportion of subjects reporting one or more psychotic-like experience was 19% (n = 72/372). These were more common in Black Caribbean (OR 2.08) and Black African subjects (OR 4.59), compared with White British. In addition, a number of indicators of childhood and adult disadvantage were associated with psychotic-like experiences. When these variables were simultaneously entered into a regression model, Black African ethnicity, concentrated adult disadvantage, and separation from parents retained a significant effect. The higher prevalence of psychotic-like experiences in the Black Caribbean, but not Black African, group was explained by high levels of social disadvantage over the life course.
Does Sickle Cell Disease Protect Against Diabetes Mellitus?
Mohamed, Ali A.; Al-Qurashi, Fathia; Whitford, David L.
2015-01-01
Objectives: The co-existence of diabetes mellitus (DM) and sickle cell disease (SCD) is rare. This study aimed to explore whether SCD patients have the same DM prevalence as the general population in a country with a high prevalence of DM. Methods: This cross-sectional study included all SCD adult patients admitted to Salmaniya Medical Complex, Bahrain, between 2003 and 2010 (n = 2,204). A random sample (n = 520) was taken to establish the prevalence of DM. Laboratory records were examined to determine the presence of DM. Results: There were 376 SCD patients with complete records; of these, 24 (6.4%) had DM. The age- and sex-standardised prevalence of DM was 8.3%. Conclusion: While the prevalence of DM in SCD patients in Bahrain was high, it was lower than expected in this population. SCD may have a protective effect towards DM development. However, the impact of these two conditions on vascular diseases suggest a need for screening and aggressive treatment in this population. PMID:25685370
Psychiatric disorders among the Mapuche in Chile.
Vicente, Benjamin; Kohn, Robert; Rioseco, Pedro; Saldivia, Sandra; Torres, Silverio
2005-06-01
The Mapuche are the largest indigenous group in Chile; yet almost all data on the mental health of indigenous populations are from North America. The study examines the differential DSM-III-R prevalence rates of psychiatric disorders and service utilization among indigenous and non-indigenous community residence. The Composite International Diagnostic Interview (CIDI) was administered to a stratified random sample of 75 Mapuche and 434 non-Mapuche residents of the province of Cautín. Lifetime prevalence and 12-month prevalence rates were estimated. Approximately 28.4% of the Mapuche population had a lifetime, and 15.7% a 12-month, prevalent psychiatric disorder compared to 38.0% and 25.7%, respectively, of the non-Mapuche. Few significant differences were noted between the two groups; however, generalized anxiety disorder, simple phobia, and drug dependence were less prevalent among the Mapuche. Service utilization among the Mapuche with mental illness was low. This is a preliminary study based on a small sample size. Further research on the mental health of indigenous populations of South America is needed.
Graham, David Y
2015-10-01
As a general rule, any clinical study where the result is already known or when the investigator(s) compares an assigned treatment against another assigned treatment known to be ineffective in the study population (e.g., in a population with known clarithromycin resistance) is unethical. As susceptibility-based therapy will always be superior to empiric therapy in any population with a prevalence of antimicrobial resistance >0%, any trial that randomizes susceptibility-based therapy with empiric therapy would be unethical. The journal Helicobacter welcomes susceptibility or culture-guided studies, studies of new therapies, and studies of adjuvants and probiotics. However, the journal will not accept for review any study we judge to be lacking clinical equipoise or which assign subjects to a treatment known to be ineffective, such as a susceptibility-based clinical trial with an empiric therapy comparator. To assist authors, we provide examples and suggestions regarding trial design for comparative studies, for susceptibility-based studies, and for studies testing adjuvants or probiotics. © 2015 John Wiley & Sons Ltd.
Graham, David Y.
2016-01-01
As a general rule, any clinical study where the result is already known or when the investigator(s) compares an assigned treatment against another assigned treatment known to be ineffective in the study population (e.g. in a population with known clarithromycin resistance) is unethical. Since susceptibility-based therapy will always be superior to empiric therapy in any population with a prevalence of antimicrobial resistance greater than 0%, any trial that randomizes susceptibility-based therapy with empiric therapy would be unethical. The journal Helicobacter welcomes susceptibility or culture-guided studies, studies of new therapies and of adjuvants and probiotics. However, the Journal will not accept for review any study we judge to be lacking clinical equipoise or which assign subjects to a treatment known to be ineffective, such as a susceptibility-based clinical trial with an empiric therapy comparator. To assist authors we provide examples and suggestion regarding trial design for comparative studies, for susceptibility-based studies, and for studies testing adjuvants or probiotics. PMID:26123529
Comorbidity of gout and rheumatoid arthritis in a large population database.
Merdler-Rabinowicz, Rona; Tiosano, Shmuel; Comaneshter, Doron; Cohen, Arnon D; Amital, Howard
2017-03-01
Coexistence of rheumatoid arthritis and gout is considered to be unusual. The current study was designed as a population-based cross-sectional study, utilizing the medical database of Clalit Health Services, the largest healthcare provider organization in Israel. Data of adult patients who were previously diagnosed with rheumatoid arthritis was retrieved. For each patient, five age- and sex-matched control patients were randomly selected. Different parameters including BMI, socioeconomic status, and existence of gout as well as smoking and hypertension were examined for both groups. The study included 11,540 patients with rheumatoid arthritis and 56,763 controls. The proportion of gout in the study group was high compared to controls (1.61 vs. 0.92%, P < 0.001). In a multivariate analysis, rheumatoid arthritis was associated with gout (OR = 1.72, 95% CI 1.45-2.05, P = 0.00). The proportion of gout in rheumatoid arthritis patients is not lower than in the general population.
Mourtzinis, Georgios; Adamsson Eryd, Samuel; Rosengren, Annika; Björck, Lena; Adiels, Martin; Johannsson, Gudmundur; Manhem, Karin
2018-05-01
Background Atrial fibrillation is associated with hyperthyroidism. Patients with primary aldosteronism have an increased prevalence of atrial fibrillation. However, the prevalence of primary aldosteronism in the atrial fibrillation population is unknown. Aim This nationwide case-control study aimed to compare the prevalence of primary aldosteronism and thyroid disorders in patients with atrial fibrillation with that of age- and sex-matched controls. Methods We identified all atrial fibrillation cases in Sweden between 1987 and 2013 ( n = 713,569) by using the Swedish National Patient Register. A control cohort without atrial fibrillation was randomly selected from the Swedish Total Population Register with a case to control ratio of 1:2. This control cohort was matched for age, sex and place of birth ( n = 1,393,953). Results The prevalence of primary aldosteronism in December 2013 was 0.056% in the atrial fibrillation cohort and 0.024% in controls. At the same time, the prevalence of hypothyroidism was 5.9% in the atrial fibrillation cohort and 3.7% in controls. The prevalence of hyperthyroidism was 2.3% in the atrial fibrillation cohort and 0.8% in controls. Conclusion This study shows, for the first time, a doubled prevalence of primary aldosteronism in a large cohort of patients with atrial fibrillation compared with the general population. There is also an increased prevalence of hypo- and hyper-thyroidism in patients with atrial fibrillation compared with the general population.
Developing and testing a decision model for predicting influenza vaccination compliance.
Carter, W B; Beach, L R; Inui, T S; Kirscht, J P; Prodzinski, J C
1986-01-01
Influenza vaccination has long been recommended for elderly high-risk patients, yet national surveys indicate that vaccination compliance rates are remarkably low (20 percent). We conducted a study to model prospectively the flu shot decisions and subsequent behavior of an elderly and/or chronically diseased (at high risk for complications of influenza) ambulatory care population at the Seattle VA Medical Center. Prior to the 1980-81 flu shot season, a random (stratified by disease) sample of 63 patients, drawn from the total population of high-risk patients in the general medicine clinic, was interviewed to identify patient-defined concerns regarding flu shots. Six potential consequences of influenza and nine of vaccination were emphasized by patients and provided the content for a weighted hierarchical utility model questionnaire. The utility model provides an operational framework for (1) obtaining subjective value and relative importance judgments from patients; (2) combining these judgments to obtain a prediction of behavioral intention and behavior for each patient; and, if the model is valid (predictive of behavior), (3) identifying those factors which are most salient to patient's decisions and subsequent behavior. Prior to the 1981-82 flu season, the decision model questionnaire was administered to 350 other high-risk patients from the same general medicine clinic population. The decision model correctly predicted behavioral intention for 87 percent and vaccination behavior for 82 percent of this population and, more importantly, differentiated shot "takers" and "nontakers" along several attitudinal dimensions that suggest specific content areas for clinical compliance intervention strategies. PMID:3949541
Sebro, Ronnie; Hoffman, Thomas J.; Lange, Christoph; Rogus, John J.; Risch, Neil J.
2013-01-01
Population stratification leads to a predictable phenomenon—a reduction in the number of heterozygotes compared to that calculated assuming Hardy-Weinberg Equilibrium (HWE). We show that population stratification results in another phenomenon—an excess in the proportion of spouse-pairs with the same genotypes at all ancestrally informative markers, resulting in ancestrally related positive assortative mating. We use principal components analysis to show that there is evidence of population stratification within the Framingham Heart Study, and show that the first principal component correlates with a North-South European cline. We then show that the first principal component is highly correlated between spouses (r=0.58, p=0.0013), demonstrating that there is ancestrally related positive assortative mating among the Framingham Caucasian population. We also show that the single nucleotide polymorphisms loading most heavily on the first principal component show an excess of homozygotes within the spouses, consistent with similar ancestry-related assortative mating in the previous generation. This nonrandom mating likely affects genetic structure seen more generally in the North American population of European descent today, and decreases the rate of decay of linkage disequilibrium for ancestrally informative markers. PMID:20842694
Observational studies of patients in the emergency department: a comparison of 4 sampling methods.
Valley, Morgan A; Heard, Kennon J; Ginde, Adit A; Lezotte, Dennis C; Lowenstein, Steven R
2012-08-01
We evaluate the ability of 4 sampling methods to generate representative samples of the emergency department (ED) population. We analyzed the electronic records of 21,662 consecutive patient visits at an urban, academic ED. From this population, we simulated different models of study recruitment in the ED by using 2 sample sizes (n=200 and n=400) and 4 sampling methods: true random, random 4-hour time blocks by exact sample size, random 4-hour time blocks by a predetermined number of blocks, and convenience or "business hours." For each method and sample size, we obtained 1,000 samples from the population. Using χ(2) tests, we measured the number of statistically significant differences between the sample and the population for 8 variables (age, sex, race/ethnicity, language, triage acuity, arrival mode, disposition, and payer source). Then, for each variable, method, and sample size, we compared the proportion of the 1,000 samples that differed from the overall ED population to the expected proportion (5%). Only the true random samples represented the population with respect to sex, race/ethnicity, triage acuity, mode of arrival, language, and payer source in at least 95% of the samples. Patient samples obtained using random 4-hour time blocks and business hours sampling systematically differed from the overall ED patient population for several important demographic and clinical variables. However, the magnitude of these differences was not large. Common sampling strategies selected for ED-based studies may affect parameter estimates for several representative population variables. However, the potential for bias for these variables appears small. Copyright © 2012. Published by Mosby, Inc.
Smith, Lauren M; Cozowicz, Crispiana; Uda, Yoshiaki; Memtsoudis, Stavros G; Barrington, Michael J
2017-12-01
Neuraxial anesthesia may improve perioperative outcomes when compared to general anesthesia; however, this is controversial. We performed a systematic review and meta-analysis using randomized controlled trials and population-based observational studies identified in MEDLINE, PubMed, and EMBASE from 2010 to May 31, 2016. Studies were included for adult patients undergoing major surgery of the trunk and lower extremity that reported: 30-day mortality (primary outcome), cardiopulmonary morbidity, surgical site infection, thromboembolic events, blood transfusion, and resource use. Perioperative outcomes were compared with general anesthesia for the following subgroups: combined neuraxial-general anesthesia and neuraxial anesthesia alone. Odds ratios (ORs) and 99% confidence intervals (CIs) were calculated to identify the impact of anesthetic technique on outcomes. Twenty-seven observational studies and 11 randomized control trials were identified. This analysis comprises 1,082,965 records from observational studies or databases and 1134 patients from randomized controlled trials. There was no difference in 30-day mortality identified when combined neuraxial-general anesthesia was compared with general anesthesia (OR 0.88; 99% CI, 0.77-1.01), or when neuraxial anesthesia was compared with general anesthesia (OR 0.98; 99% CI, 0.92-1.04). When combined neuraxial-general anesthesia was compared with general anesthesia, combined neuraxial-general anesthesia was associated with a reduced odds of pulmonary complication (OR 0.84; 99% CI, 0.79-0.88), surgical site infection (OR 0.93; 99% CI, 0.88-0.98), blood transfusion (OR 0.90; 99% CI, 0.87-0.93), thromboembolic events (OR 0.84; 99% CI, 0.73-0.98), length of stay (mean difference -0.16 days; 99% CI, -0.17 to -0.15), and intensive care unit admission (OR 0.77; 99% CI, 0.73-0.81). For the combined neuraxial-general anesthesia subgroup, there were increased odds of myocardial infarction (OR 1.18; 99% CI, 1.01-1.37). There was no difference identified in the odds of pneumonia (OR 0.94; 99% CI, 0.87-1.02) or cardiac complications (OR 1.04; 99% CI, 1.00-1.09) for the combined neuraxial-general anesthesia subgroup. When neuraxial anesthesia was compared to general anesthesia, there was a decreased odds of any pulmonary complication (OR 0.38; 99% CI, 0.36-0.40), surgical site infection (OR 0.76; 99% CI, 0.71-0.82), blood transfusion (OR 0.85; 99% CI, 0.82-0.88), thromboembolic events (OR 0.79; 99% CI, 0.68-0.91), length of stay (mean difference -0.29 days; 99% CI, -0.29 to -0.28), and intensive care unit admission (OR 0.50; 99% CI, 0.48-0.53). There was no difference in the odds of cardiac complications (OR 0.99; 99% CI, 0.94-1.03), myocardial infarction (OR 0.91; 99% CI, 0.81-1.02), or pneumonia (OR 0.92; 99% CI, 0.84-1.01). Randomized control trials revealed no difference in requirement for blood transfusion (RR 1.05; 99% CI, 0.65-1.71) and a decreased length of stay (mean difference -0.15 days; 99% CI, -0.27 to -0.04). Neuraxial anesthesia when combined with general anesthesia or when used alone was not associated with decreased 30-day mortality. Neuraxial anesthesia may improve pulmonary outcomes and reduce resource use when compared with general anesthesia. However, because observational studies were included in this analysis, there is a risk of residual confounding and therefore these results should be interpreted with caution.
2014-01-01
Background Back and neck disability are frequent in older adults resulting in loss of function and independence. Exercise therapy and manual therapy, like spinal manipulative therapy (SMT), have evidence of short and intermediate term effectiveness for spinal disability in the general population and growing evidence in older adults. For older populations experiencing chronic spinal conditions, long term management may be more appropriate to maintain improvement and minimize the impact of future exacerbations. Research is limited comparing short courses of treatment to long term management of spinal disability. The primary aim is to compare the relative effectiveness of 12 weeks versus 36 weeks of SMT and supervised rehabilitative exercise (SRE) in older adults with back and neck disability. Methods/Design Randomized, mixed-methods, comparative effectiveness trial conducted at a university-affiliated research clinic in the Minneapolis/St. Paul, Minnesota metropolitan area. Participants Independently ambulatory community dwelling adults ≥ 65 years of age with back and neck disability of minimum 12 weeks duration (n = 200). Interventions 12 weeks SMT + SRE or 36 weeks SMT + SRE. Randomization Blocked 1:1 allocation; computer generated scheme, concealed in sequentially numbered, opaque, sealed envelopes. Blinding Functional outcome examiners are blinded to treatment allocation; physical nature of the treatments prevents blinding of participants and providers to treatment assignment. Primary endpoint 36 weeks post-randomization. Data collection Self-report questionnaires administered at 2 baseline visits and 4, 12, 24, 36, 52, and 78 weeks post-randomization. Primary outcomes include back and neck disability, measured by the Oswestry Disability Index and Neck Disability Index. Secondary outcomes include pain, general health status, improvement, self-efficacy, kinesiophobia, satisfaction, and medication use. Functional outcome assessment occurs at baseline and week 37 for hand grip strength, short physical performance battery, and accelerometry. Individual qualitative interviews are conducted when treatment ends. Data on expectations, falls, side effects, and adverse events are systematically collected. Primary analysis Linear mixed-model method for repeated measures to test for between-group differences with baseline values as covariates. Discussion Treatments that address the management of spinal disability in older adults may have far reaching implications for patient outcomes, clinical guidelines, and healthcare policy. Trial registry www.ClinicalTrials.gov; Identifier: NCT01057706. PMID:25478141
Waxman, D
2012-06-01
A fundamental result of population genetics states that a new mutation, at an unlinked neutral locus in a randomly mating diploid population, has a mean time of fixation of ∼4N(e) generations, where N(e) is the effective population size. This result is based on an assumption of fixed population size, which does not universally hold in natural populations. Here, we analyze such neutral fixations in populations of changing size within the framework of the diffusion approximation. General expressions are derived for the mean and variance of the fixation time in changing populations. Some explicit results are given for two cases: (i) the effective population size undergoes a sudden change, representing a sudden population expansion or a sudden bottleneck; (ii) the effective population changes linearly for a limited period of time and then remains constant. Additionally, a lower bound for the mean time of fixation is obtained for an effective population size that increases with time, and this is applied to exponentially growing populations. The results obtained in this work show, among other things, that for populations that increase in size, the mean time of fixation can be enhanced, sometimes substantially so, over 4N(e,0) generations, where N(e,0) is the effective population size at the time the mutation arises. Such an enhancement is associated with (i) an increased probability of neutral polymorphism in a population and (ii) an enhanced persistence of high-frequency neutral variation, which is the variation most likely to be observed.
De Jager, N. R.; Pastor, J.
2009-01-01
Ungulate herbivores create patterns of forage availability, plant species composition, and soil fertility as they range across large landscapes and consume large quantities of plant material. Over time, herbivore populations fluctuate, producing great potential for spatio-temporal landscape dynamics. In this study, we extend the spatial and temporal extent of a long-term investigation of the relationship of landscape patterns to moose foraging behavior at Isle Royale National Park, MI. We examined how patterns of browse availability and consumption, plant basal area, and soil fertility changed during a recent decline in the moose population. We used geostatistics to examine changes in the nature of spatial patterns in two valleys over 18 years and across short-range and long-range distance scales. Landscape patterns of available and consumed browse changed from either repeated patches or randomly distributed patches in 1988-1992 to random point distributions by 2007 after a recent record high peak followed by a rapid decline in the moose population. Patterns of available and consumed browse became decoupled during the moose population low, which is in contrast to coupled patterns during the earlier high moose population. Distributions of plant basal area and soil nitrogen availability also switched from repeated patches to randomly distributed patches in one valley and to random point distributions in the other valley. Rapid declines in moose population density may release vegetation and soil fertility from browsing pressure and in turn create random landscape patterns. ?? Springer Science+Business Media B.V. 2009.
Dreisler, Eva; Stampe Sørensen, Søren
2014-08-01
To estimate the prevalence of uterine müllerian duct anomalies in a general population. Cross-sectional study. University hospital in collaboration with the Danish Civil Registry. A total of 1,654 women randomly recruited from a general population; 686 women were eligible and accepted inclusion (429 pre- and 257 postmenopausal). Saline contrast sonohysterography (SCSH) was finally performed in 622 women (aged 20-74 years) (the procedure was impossible owing to cervical stenosis in 58, contraindicated in 2, other patient-related factors in 4). The shape of the uterus was dynamically evaluated in the transversal and longitudinal planes during SCSH and classified in accordance with American Fertility Society as normal, arcuate, septate (partial, complete), bicorn (partial, complete), or unicorn. History of previous miscarriage and menstrual cycle was obtained by a questionnaire. Prevalence of müllerian anomalies, miscarriage, and oligomenorrhea. The overall prevalence of müllerian anomalies was 9.8% (61 of 622) (95% confidence interval [CI] 7.5-12.1). The majority had arcuate uteri (n=42, 6.8%), 17 partial septate (2.7%), 1 complete septate (1.6%), and 1 unicorn uterus (1.6%). Müllerian anomalies were significantly more frequently diagnosed in nulliparous (20% [26 of 128]) compared with parous women (7% [35 of 494]). Müllerian anomalies were more frequent in women with oligomenorrhea compared with women with normal menstrual periods (19% [15 of 79] vs. 10% [34 of 339]). One first-trimester miscarriage or multiple miscarriages (more than one) were not significantly more frequent in premenopausal women with müllerian anomalies compared with women with normal-shaped uteri (24% [6 of 25] vs. 22% [57 of 265]). In a general population examined by SCSH the prevalence of Müllerian anomalies is estimated at 9.8%. Müllerian anomalies were more frequent in nulliparous women. Both impaired fertility and a pregnancy-associated modulation of the uterine corpus are among explanations. Müllerian anomalies were associated with oligomenorrhea in premenopausal women. In this general population there was no association between miscarriage and müllerian anomalies; however, the number of cases was limited. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Ethics in the Use of Extracorporeal Cardiopulmonary Resuscitation in Adults
Riggs, Kevin R.; Becker, Lance B.; Sugarman, Jeremy
2015-01-01
Extracorporeal cardiopulmonary resuscitation (ECPR) promises to be an important advance in the treatment of cardiac arrest. However, ECPR involves ethical challenges that should be addressed as it diffuses into practice. Benefits and risks are uncertain, so the evidence base needs to be further developed, at least through outcomes registries and potentially with randomized trials. To inform decision making, patients’ preferences regarding ECPR should be obtained, both from the general population and from inpatients at risk for cardiac arrest. Fair and transparent appropriate use criteria should be developed and could be informed by economic analyses. PMID:25866287
The dimensionality of DSM5 alcohol use disorder in Puerto Rico.
Caetano, Raul; Vaeth, Patrice A C; Santiago, Katyana; Canino, Glorisa
2016-11-01
Test the dimensionality and measurement properties of lifetime DSM-5 AUD criteria in a sample of adults from the metropolitan area of San Juan, Puerto Rico. Cross-sectional study with survey data collected in 2013-2014. General population. Random household sample of the adult population 18 to 64years of age in San Juan, Puerto Rico (N=1510; lifetime drinker N=1107). DSM-5 alcohol use disorder (2 or more criteria present in 12months). Lifetime reports of AUD criteria were consistent with a one-dimensional model. Scalar measurement invariance was observed across gender, but measurement parameters for tolerance varied across age, with younger ages showing a lower threshold and steeper loading. Results provide support for a unidimensional DSM-5 AUD construct in a sample from a Latin American country. Copyright © 2016 Elsevier Ltd. All rights reserved.
Agent based modeling of the coevolution of hostility and pacifism
NASA Astrophysics Data System (ADS)
Dalmagro, Fermin; Jimenez, Juan
2015-01-01
We propose a model based on a population of agents whose states represent either hostile or peaceful behavior. Randomly selected pairs of agents interact according to a variation of the Prisoners Dilemma game, and the probabilities that the agents behave aggressively or not are constantly updated by the model so that the agents that remain in the game are those with the highest fitness. We show that the population of agents oscillate between generalized conflict and global peace, without either reaching a stable state. We then use this model to explain some of the emergent behaviors in collective conflicts, by comparing the simulated results with empirical data obtained from social systems. In particular, using public data reports we show how the model precisely reproduces interesting quantitative characteristics of diverse types of armed conflicts, public protests, riots and strikes.
Safety of Reiki Therapy for Newborns at Risk for Neonatal Abstinence Syndrome
Wright-Esber, Sandra; Zupancic, Julie; Gargiulo, Deb; Woodall, Patricia
2018-01-01
The incidence of opioid abuse and subsequent drug withdrawal is exponentially on the rise in the United States for many populations including newborns who are born to drug-addicted mothers. These newborns often exhibit symptoms of neonatal abstinence syndrome (NAS) within 24 to 72 hours of birth. Treatment of NAS includes monitoring of withdrawal symptoms, managing physiological parameters, and the use of supportive and pharmacologic treatments. Although a few randomized controlled trials exist, studies on supportive intervention are generally limited by small sample sizes, case study reports, expert opinions, and descriptive design. Few studies address the safety of Reiki for newborns at risk for NAS using neonatal parameters. This pilot study addresses feasibility and demonstrates that Reiki is safe when administered to this high-risk population. Considerations for future studies are discussed. PMID:29315084
Image encryption using random sequence generated from generalized information domain
NASA Astrophysics Data System (ADS)
Xia-Yan, Zhang; Guo-Ji, Zhang; Xuan, Li; Ya-Zhou, Ren; Jie-Hua, Wu
2016-05-01
A novel image encryption method based on the random sequence generated from the generalized information domain and permutation-diffusion architecture is proposed. The random sequence is generated by reconstruction from the generalized information file and discrete trajectory extraction from the data stream. The trajectory address sequence is used to generate a P-box to shuffle the plain image while random sequences are treated as keystreams. A new factor called drift factor is employed to accelerate and enhance the performance of the random sequence generator. An initial value is introduced to make the encryption method an approximately one-time pad. Experimental results show that the random sequences pass the NIST statistical test with a high ratio and extensive analysis demonstrates that the new encryption scheme has superior security.
Penna Bit-String Model with Constant Population
NASA Astrophysics Data System (ADS)
de Oliveira, P. M. C.; de Oliveira, S. Moss; Sá Martins, J. S.
We removed from the Penna model for biological aging any random killing Verhulst factor. Deaths are due only to genetic diseases and the population size is fixed, instead of fluctuating around some constant value. We show that these modifications give qualitatively the same results obtained in an earlier paper, where the random killings (used to avoid an exponential increase of the population) were applied only to newborns.
van der Zweerde, Tanja; Lancee, Jaap; Slottje, Pauline; Bosmans, Judith; Van Someren, Eus; Reynolds, Charles; Cuijpers, Pim; van Straten, Annemieke
2016-04-02
Insomnia is a highly prevalent disorder causing clinically significant distress and impairment. Furthermore, insomnia is associated with high societal and individual costs. Although cognitive behavioural treatment for insomnia (CBT-I) is the preferred treatment, it is not used often. Offering CBT-I in an online format may increase access. Many studies have shown that online CBT for insomnia is effective. However, these studies have all been performed in general population samples recruited through media. This protocol article presents the design of a study aimed at establishing feasibility, effectiveness and cost-effectiveness of a guided online intervention (i-Sleep) for patients suffering from insomnia that seek help from their general practitioner as compared to care-as-usual. In a pragmatic randomized controlled trial, adult patients with insomnia disorder recruited through general practices are randomized to a 5-session guided online treatment, which is called "i-Sleep", or to care-as-usual. Patients in the care-as-usual condition will be offered i-Sleep 6 months after inclusion. An ancillary clinician, known as the psychological well-being practitioner who works in the GP practice (PWP; in Dutch: POH-GGZ), will offer online support after every session. Our aim is to recruit one hundred and sixty patients. Questionnaires, a sleep diary and wrist actigraphy will be administered at baseline, post intervention (at 8 weeks), and at 6 months and 12 months follow-up. Effectiveness will be established using insomnia severity as the main outcome. Cost-effectiveness and cost-utility (using costs per quality adjusted life year (QALY) as outcome) will be conducted from a societal perspective. Secondary measures are: sleep diary, daytime consequences, fatigue, work and social adjustment, anxiety, alcohol use, depression and quality of life. The results of this trial will help establish whether online CBT-I is (cost-) effective and feasible in general practice as compared to care-as-usual. If it is, then quality of care might be increased because implementation of i-Sleep makes it easier to adhere to insomnia guidelines. Strengths and limitations are discussed. Netherlands Trial register NTR 5202 (registered April 17(st) 2015).
Rochon, Paula A.; Mashari, Azad; Cohen, Ariel; Misra, Anjali; Laxer, Dara; Streiner, David L.; Dergal, Julie M.; Clark, Jocalyn P.; Gold, Jennifer; Binns, Malcolm A.
2004-01-01
Background More than two-thirds of the world's population live in low-income countries, where health priorities are different from those of people living in more affluent parts of the world. We evaluated the relation between the global burden of disease and conditions or diseases studied in randomized controlled trials (RCTs) published in general medical journals. Methods A MEDLINE search identified 373 RCTs that had been published in 6 international peer-reviewed general medical journals in 1999. Manual review excluded non-RCTs, brief reports and trials in which the unit of randomization was not the patient; 286 RCTs remained eligible for analysis. We identified the RCTs that studied any of the 40 leading causes of the global burden of disease. Five of these conditions were considered unsuitable for study with an RCT design and were excluded from subsequent analysis. To provide a practical perspective, we asked 12 experts working with international health organizations to rate the relevance to global health of the articles that studied any of the top 10 causes of the global burden of disease, as measured by disability-adjusted life years (DALYs) and mortality, using a 5-point Likert scale. Results Among the 286 RCTs in our sample, 124 (43.4%) addressed 1 of the 35 leading causes of the global burden of disease. Of these, ischemic heart disease, HIV/AIDS and cerebrovascular disease were the most commonly studied conditions. Ninety articles (31.5%) studied 1 of the top 10 causes of the global burden of disease. The mean rating (and standard deviation) for international health relevance assigned by experts was 2.6 (1.5) out of 5. Only 14 (16%) of the 90 trials received a rating of 4 or greater, indicating high relevance to international health. Almost half of the 40 leading causes of the global burden of disease were not studied by any trial. Interpretation Many conditions or diseases common internationally are underrepresented in RCTs published in leading general medical journals. Trials published in these journals that studied one of these high-priority conditions were generally rated as being of little relevance to international health. PMID:15159365
Randomness and diversity matter in the maintenance of the public resources
NASA Astrophysics Data System (ADS)
Liu, Aizhi; Zhang, Yanling; Chen, Xiaojie; Sun, Changyin
2017-03-01
Most previous models about the public goods game usually assume two possible strategies, i.e., investing all or nothing. The real-life situation is rarely all or nothing. In this paper, we consider that multiple strategies are adopted in a well-mixed population, and each strategy represents an investment to produce the public goods. Past efforts have found that randomness matters in the evolution of fairness in the ultimatum game. In the framework involving no other mechanisms, we study how diversity and randomness influence the average investment of the population defined by the mean value of all individuals' strategies. The level of diversity is increased by increasing the strategy number, and the level of randomness is increased by increasing the mutation probability, or decreasing the population size or the selection intensity. We find that a higher level of diversity and a higher level of randomness lead to larger average investment and favor more the evolution of cooperation. Under weak selection, the average investment changes very little with the strategy number, the population size, and the mutation probability. Under strong selection, the average investment changes very little with the strategy number and the population size, but changes a lot with the mutation probability. Under intermediate selection, the average investment increases significantly with the strategy number and the mutation probability, and decreases significantly with the population size. These findings are meaningful to study how to maintain the public resource.
The Danish National Health Survey 2010. Study design and respondent characteristics.
Christensen, Anne Illemann; Ekholm, Ola; Glümer, Charlotte; Andreasen, Anne Helms; Hvidberg, Michael Falk; Kristensen, Peter Lund; Larsen, Finn Breinholt; Ortiz, Britta; Juel, Knud
2012-06-01
In 2010 the five Danish regions and the National Institute of Public Health at the University of Southern Denmark conducted a national representative health survey among the adult population in Denmark. This paper describes the study design and the sample and study population as well as the content of the questionnaire. The survey was based on five regional stratified random samples and one national random sample. The samples were mutually exclusive. A total of 298,550 individuals (16 years or older) were invited to participate. Information was collected using a mixed mode approach (paper and web questionnaires). A questionnaire with a minimum of 52 core questions was used in all six subsamples. Calibrated weights were computed in order to take account of the complex survey design and reduce non-response bias. In all, 177,639 individuals completed the questionnaire (59.5%). The response rate varied from 52.3% in the Capital Region of Denmark sample to 65.5% in the North Denmark Region sample. The response rate was particularly low among young men, unmarried people and among individuals with a different ethnic background than Danish. The survey was a result of extensive national cooperation across sectors, which makes it unique in its field of application, e.g. health surveillance, planning and prioritizing public health initiatives and research. However, the low response rate in some subgroups of the study population can pose problems in generalizing data, and efforts to increase the response rate will be important in the forthcoming surveys.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gillet, N.; Ocvirk, P.; Aubert, D.
2015-02-10
We search for vast planes of satellites (VPoS) in a high-resolution simulation of the Local Group performed by the CLUES project, which improves significantly the resolution of previous similar studies. We use a simple method for detecting planar configurations of satellites, and validate it on the known plane of M31. We implement a range of prescriptions for modeling the satellite populations, roughly reproducing the variety of recipes used in the literature, and investigate the occurrence and properties of planar structures in these populations. The structure of the simulated satellite systems is strongly non-random and contains planes of satellites, predominantly co-rotating,more » with, in some cases, sizes comparable to the plane observed in M31 by Ibata et al. However, the latter is slightly richer in satellites, slightly thinner, and has stronger co-rotation, which makes it stand out as overall more exceptional than the simulated planes, when compared to a random population. Although the simulated planes we find are generally dominated by one real structure forming its backbone, they are also partly fortuitous and are thus not kinematically coherent structures as a whole. Provided that the simulated and observed planes of satellites are indeed of the same nature, our results suggest that the VPoS of M31 is not a coherent disk and that one-third to one-half of its satellites must have large proper motions perpendicular to the plane.« less
A model of tuberculosis transmission and intervention strategies in an urban residential area.
Pienaar, Elsje; Fluitt, Aaron M; Whitney, Scott E; Freifeld, Alison G; Viljoen, Hendrik J
2010-04-01
The model herein aims to explore the dynamics of the spread of tuberculosis (TB) in an informal settlement or township. The population is divided into households of various sizes and also based on commuting status. The model dynamics distinguishes between three distinct social patterns: the exposure of commuters during travel, random diurnal interaction and familial exposure at night. Following the general SLIR models, the population is further segmented into susceptible (S), exposed/latently infected (L), active/infectious (I), and recovered (R) individuals. During the daytime, commuters travel on public transport, while non-commuters randomly interact in the community to mimic chance encounters with infectious persons. At night, each family interacts and sleeps together in the home. The risk of exposure to TB is based on the proximity, duration, and frequency of encounters with infectious persons. The model is applied to a hypothetical population to explore the effects of different intervention strategies including vaccination, wearing of masks during the commute, prophylactic treatment of latent infections and more effective case-finding and treatment. The most important findings of the model are: (1) members of larger families are responsible for more disease transmissions than those from smaller families, (2) daily commutes on public transport provide ideal conditions for transmission of the disease, (3) improved diagnosis and treatment has the greatest impact on the spread of the disease, and (4) detecting TB at the first clinic visit, when patients are still smear negative, is key. Copyright 2010 Elsevier Ltd. All rights reserved.
Vihstadt, Corrie; Maiers, Michele; Westrom, Kristine; Bronfort, Gert; Evans, Roni; Hartvigsen, Jan; Schulz, Craig
2014-01-01
Back and neck disability are frequent in older adults resulting in loss of function and independence. Exercise therapy and manual therapy, like spinal manipulative therapy (SMT), have evidence of short and intermediate term effectiveness for spinal disability in the general population and growing evidence in older adults. For older populations experiencing chronic spinal conditions, long term management may be more appropriate to maintain improvement and minimize the impact of future exacerbations. Research is limited comparing short courses of treatment to long term management of spinal disability. The primary aim is to compare the relative effectiveness of 12 weeks versus 36 weeks of SMT and supervised rehabilitative exercise (SRE) in older adults with back and neck disability. Randomized, mixed-methods, comparative effectiveness trial conducted at a university-affiliated research clinic in the Minneapolis/St. Paul, Minnesota metropolitan area. Independently ambulatory community dwelling adults ≥ 65 years of age with back and neck disability of minimum 12 weeks duration (n = 200). 12 weeks SMT + SRE or 36 weeks SMT + SRE. Blocked 1:1 allocation; computer generated scheme, concealed in sequentially numbered, opaque, sealed envelopes. Functional outcome examiners are blinded to treatment allocation; physical nature of the treatments prevents blinding of participants and providers to treatment assignment. 36 weeks post-randomization. Self-report questionnaires administered at 2 baseline visits and 4, 12, 24, 36, 52, and 78 weeks post-randomization. Primary outcomes include back and neck disability, measured by the Oswestry Disability Index and Neck Disability Index. Secondary outcomes include pain, general health status, improvement, self-efficacy, kinesiophobia, satisfaction, and medication use. Functional outcome assessment occurs at baseline and week 37 for hand grip strength, short physical performance battery, and accelerometry. Individual qualitative interviews are conducted when treatment ends. Data on expectations, falls, side effects, and adverse events are systematically collected. Linear mixed-model method for repeated measures to test for between-group differences with baseline values as covariates. Treatments that address the management of spinal disability in older adults may have far reaching implications for patient outcomes, clinical guidelines, and healthcare policy. www.ClinicalTrials.gov; Identifier: NCT01057706.
Training set optimization under population structure in genomic selection.
Isidro, Julio; Jannink, Jean-Luc; Akdemir, Deniz; Poland, Jesse; Heslot, Nicolas; Sorrells, Mark E
2015-01-01
Population structure must be evaluated before optimization of the training set population. Maximizing the phenotypic variance captured by the training set is important for optimal performance. The optimization of the training set (TRS) in genomic selection has received much interest in both animal and plant breeding, because it is critical to the accuracy of the prediction models. In this study, five different TRS sampling algorithms, stratified sampling, mean of the coefficient of determination (CDmean), mean of predictor error variance (PEVmean), stratified CDmean (StratCDmean) and random sampling, were evaluated for prediction accuracy in the presence of different levels of population structure. In the presence of population structure, the most phenotypic variation captured by a sampling method in the TRS is desirable. The wheat dataset showed mild population structure, and CDmean and stratified CDmean methods showed the highest accuracies for all the traits except for test weight and heading date. The rice dataset had strong population structure and the approach based on stratified sampling showed the highest accuracies for all traits. In general, CDmean minimized the relationship between genotypes in the TRS, maximizing the relationship between TRS and the test set. This makes it suitable as an optimization criterion for long-term selection. Our results indicated that the best selection criterion used to optimize the TRS seems to depend on the interaction of trait architecture and population structure.
Ni, Michael Y; Li, Tom K; Yu, Nancy X; Pang, Herbert; Chan, Brandford H Y; Leung, Gabriel M; Stewart, Sunita M
2016-01-01
To examine whether the two-item version (CD-RISC2) of the Connor-Davidson Resilience Scale (CD-RISC) has adequate internal consistency and construct validity, as well as significant correlation with the full scale, and to provide normative data for the CD-RISC and the CD-RISC2 in a Chinese general population in Hong Kong. In total, 10,997 randomly selected participants aged ≥20 years completed the Chinese version of the CD-RISC (including the 2 items of the CD-RISC2), the Patient Health Questionnaire, Family Harmony Scale, Family APGAR, and CAGE Questionnaire. Internal consistency and convergent and discriminant validity of the CD-RISC and CD-RISC2 were assessed. Cronbach's α for CD-RISC and CD-RISC2 was 0.97 and 0.79, respectively. CD-RISC2 was associated with the 25-item version of the CD-RISC (r = 0.88), depressive symptoms (r s = -0.18), family harmony (r = 0.20), family functioning (r = 0.27) and was not associated with alcohol consumption (r = 0.05). The mean score for the CD-RISC and CD-RISC2 was 59.99 (SD = 13.92) and 5.03 (SD = 1.37), respectively. Men, younger individuals, and those with higher education or higher household income reported higher resilience levels. The Chinese version of the CD-RISC2 was demonstrated to be a reliable and valid measure in assessing resilience among the general population in Hong Kong.
The re-identification risk of Canadians from longitudinal demographics
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
Otsuka, Yuichiro; Kaneita, Yoshitaka; Itani, Osamu; Nakagome, Sachi; Jike, Maki; Ohida, Takashi
2017-09-01
To clarify the prevalence of stress, and examine the relationship between sleep disorders and stress coping strategies among highly stressed individuals in the general Japanese population. A cross-sectional nationwide survey was undertaken in November 2007. Men and women were randomly selected from 300 districts throughout Japan. Data from 7671 (3532 men (average age 53.5 ± 17.0 years) and 4139 women (average age 53.9 ± 17.7 years)) were analyzed. Participants completed a self-reported questionnaire on stress, sleep disorders, and stress coping strategies in the previous month. Highly stressed individuals comprised 16.6% (95% confidence interval 15.8-17.5%) of the total sample, and most were aged 20-49 years. In multiple logistic regression, symptoms of insomnia (ie, difficulty initiating sleep, difficulty maintaining sleep, and early morning awakening), excessive daytime sleepiness, nightmares, daytime malfunction, and lack of rest due to sleep deprivation were more prone to occur in highly stressed individuals. In addition, logistic regression analysis controlling for other adjustment factors revealed that stress coping strategies such as 'giving up on problem-solving', 'enduring problems patiently', 'smoking' and 'drinking alcohol' were positively associated with the above-mentioned sleep disorders. On the other hand, stress coping strategies such as 'exercising', 'enjoying hobbies', and 'sharing worries' were inversely associated with the above-mentioned sleep disorders. Distraction-based stress coping (eg, hobbies, exercise, and optimistic thinking) was found to be preferable to problem-based stress coping in a highly stressed Japanese general population. Copyright © 2017 Elsevier B.V. All rights reserved.
Prevalence of renal stones in an Italian urban population: a general practice-based study.
Croppi, Emanuele; Ferraro, Pietro Manuel; Taddei, Luca; Gambaro, Giovanni
2012-10-01
Kidney stones represent a common condition characterized by significant morbidity and economic costs. The epidemiology of kidney stones is not completely understood and may vary substantially based on geographic, socioeconomic and clinical factors; the present study aims at defining the prevalence and diagnostic patterns of kidney stones in a cohort representative of the general population in Florence, Italy. A sample of 1,543 adult subjects, all Caucasians, was randomly selected from a population of over 25,000 subjects followed by 22 general practitioners (GPs). Subjects were administered a questionnaire requesting the patient's age and sex, any history of kidney stones and/or colics and the prescription of kidney ultrasound (US) examination. GPs data-bases were also interrogated. Crude and adjusted prevalence proportions and ratios (PRs) with corresponding 95% confidence intervals (CIs) were computed. Furthermore, the association between the practice pattern of each physician with respect to US prescription and the prevalence of kidney stones was investigated. The overall prevalence of kidney stones was 7.5% (95% confidence interval 6.2, 8.9%), increasing with age until 55-60 years and then decreasing. About 50% reported recurrent disease. There were no significant differences in prevalence among males and females. GPs who tended to prescribe more US examinations were more likely to have more patients with kidney stones (adjusted PR 1.80, 95% CI 1.11, 2.94; p = 0.020). The present study confirms both the high prevalence and the regional variability of kidney stones. Practice patterns may be involved in such variability.
Improved long-term survival with subdural drains following evacuation of chronic subdural haematoma.
Guilfoyle, Mathew R; Hutchinson, Peter J A; Santarius, Thomas
2017-05-01
Chronic subdural haematoma (CSDH) is a common condition that is effectively managed by burrhole drainage but requires repeat surgery in a significant minority of patients. The Cambridge Chronic Subdural Haematoma Trial (CCSHT) was a randomised controlled study that showed placement of subdural drains for 48 h following burrhole evacuation significantly reduces the incidence of reoperation and improves survival at 6 months. The present study examined the long-term survival of the patients in the trial. In the original trial patients at a single neurosurgical centre from 2004-2007 were randomly assigned to receive a drain (n = 108) or no drain (n = 107) following burrhole drainage of CSDH. We ascertained whether the trial patients were alive in February 2016-a minimum of 8 years following enrollment-via the UK NHS tracing service. Survival was compared between the trial groups and against expected survival for the UK general population matched for age and sex. At 5 years following surgery the drain group continued to have significantly better survival than the no drain patients (p = 0.027), but this was no longer apparent at 10 years. Survival of patients in the drain group did not differ significantly from that of the general population whereas patients who did not receive a drain had significantly lower survival than expected (p = 0.0006). Subdural drains following CSDH evacuation are associated with improved long-term survival, which appears similar to that expected for the general population of the same age and sex. All patients having burrhole CSDH evacuation should receive a drain as standard practice unless specifically contraindicated.
Actual and predicted prevalence of alcohol consumption during pregnancy in the WHO African Region.
Popova, Svetlana; Lange, Shannon; Probst, Charlotte; Shield, Kevin; Kraicer-Melamed, Hannah; Ferreira-Borges, Carina; Rehm, Jürgen
2016-10-01
To estimate the prevalence of alcohol consumption and binge drinking during pregnancy among the general population in the World Health Organization (WHO) African Region, by country. First, a comprehensive systematic literature search was performed to identify all published and unpublished studies. Then, several meta-analyses, assuming a random-effects model, were conducted to estimate the prevalence of alcohol consumption and binge drinking during pregnancy among the general population for countries in the WHO African Region with two or more studies available. Lastly, for countries with less than two studies or no known data predictions were obtained using regression modelling. The estimated prevalence of alcohol consumption during pregnancy among the general population ranged from 2.2% (95% confidence interval [CI]: 1.6-2.8%; Equatorial Guinea) to 12.6% (95% CI: 9.9-15.4%; Cameroon) in Central Africa, 3.4% (95% CI: 2.6-4.3%; Seychelles) to 20.5% (95% CI: 16.4-24.7%; Uganda) in Eastern Africa, 5.7% (95% CI: 4.4-7.1%; Botswana) to 14.2% (95% CI: 11.1-17.3%; Namibia) in Southern Africa, 6.6% (95% CI: 5.0-8.3%; Mauritania) to 14.8% (95% CI: 11.6-17.9%; Sierra Leone) in Western Africa, and 4.3% (95% CI: 3.2-5.3%; Algeria) in Northern Africa. The high prevalence of alcohol consumption and binge drinking during pregnancy in some African countries calls for educational campaigns, screening and targeted interventions for women of childbearing age. © 2016 John Wiley & Sons Ltd.