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Sample records for random population-based sample

  1. Association of macronutrient intake patterns with being overweight in a population-based random sample of men in France.

    Science.gov (United States)

    Ahluwalia, N; Ferrières, J; Dallongeville, J; Simon, C; Ducimetière, P; Amouyel, P; Arveiler, D; Ruidavets, J-B

    2009-04-01

    Diet is considered an important modifiable factor in the overweight. The role of macronutrients in obesity has been examined in general in selected populations, but the results of these studies are mixed, depending on the potential confounders and adjustments for other macronutrients. For this reason, we examined the association between macronutrient intake patterns and being overweight in a population-based representative sample of middle-aged (55.1+/-6.1 years) men (n=966), using various adjustment modalities. The study subjects kept 3-day food-intake records, and the standard cardiovascular risk factors were assessed. Weight, height and waist circumference (WC) were also measured. Carbohydrate intake was negatively associated and fat intake was positively associated with body mass index (BMI) and WC in regression models adjusted for energy intake and other factors, including age, smoking and physical activity. However, with mutual adjustments for other energy-yielding nutrients, the negative association of carbohydrate intake with WC remained significant, whereas the associations between fat intake and measures of obesity did not. Adjusted odds ratios (95% confidence interval) comparing the highest and lowest quartiles of carbohydrate intake were 0.50 (0.25-0.97) for obesity (BMI>29.9) and 0.41 (0.23-0.73) for abdominal obesity (WC>101.9 cm). Consistent negative associations between carbohydrate intake and BMI and WC were seen in this random representative sample of the general male population. The associations between fat intake and these measures of being overweight were attenuated on adjusting for carbohydrate intake. Thus, the balance of carbohydrate-to-fat intake is an important element in obesity in a general male population, and should be highlighted in dietary guidelines.

  2. Analytical decision model for sample size and effectiveness projections for use in planning a population-based randomized controlled trial of colorectal cancer screening.

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    Chiu, Sherry Y-H; Malila, Nea; Yen, Amy M-F; Anttila, Ahti; Hakama, Matti; Chen, H-H

    2011-02-01

    Population-based randomized controlled trials (RCTs) often involve enormous costs and long-term follow-up to evaluate primary end points. Analytical decision-simulated model for sample size and effectiveness projections based on primary and surrogate end points are necessary before planning a population-based RCT. Based on the study design similar to two previous RCTs, transition rates were estimated using a five-state natural history model [normal, preclinical detection phase (PCDP) Dukes' A/B, PCDP Dukes' C/D, Clinical Dukes' A/B and Clinical Dukes' C/D]. The Markov cycle tree was assigned transition parameters, variables related to screening and survival rate that simulated results of 10-year follow-up in the absence of screening for a hypothetical cohort aged 45-74 years. The corresponding screened arm was to simulate the results after the introduction of population-based screening for colorectal cancer with fecal occult blood test with stop screen design. The natural course of mean sojourn time for five-state Markov model were estimated as 2.75 years for preclinical Dukes' A/B and 1.38 years for preclinical Dukes' C/D. The expected reductions in mortality and Dukes' C/D were 13% (95% confidence intervals: 7-19%) and 26% (95% confidence intervals: 20-32%), respectively, given a 70% acceptance rate and a 90% colonoscopy referral rate. Sample sizes required were 86,150 and 65,592 subjects for the primary end point and the surrogate end point, respectively, given an incidence rate up to 0.0020 per year. The sample sizes required for primary and surrogate end points and the projection of effectiveness of fecal occult blood test for colorectal cancer screening were developed. Both are very important to plan a population-based RCT. © 2010 Blackwell Publishing Ltd.

  3. Nutritional status and falls in community-dwelling older people: a longitudinal study of a population-based random sample.

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    Chien, Ming-Hung; Guo, How-Ran

    2014-01-01

    Falls are common in older people and may lead to functional decline, disability, and death. Many risk factors have been identified, but studies evaluating effects of nutritional status are limited. To determine whether nutritional status is a predictor of falls in older people living in the community, we analyzed data collected through the Survey of Health and Living Status of the Elderly in Taiwan (SHLSET). SHLSET include a series of interview surveys conducted by the government on a random sample of people living in community dwellings in the nation. We included participants who received nutritional status assessment using the Mini Nutritional Assessment Taiwan Version 2 (MNA-T2) in the 1999 survey when they were 53 years or older and followed up on the cumulative incidence of falls in the one-year period before the interview in the 2003 survey. At the beginning of follow-up, the 4440 participants had a mean age of 69.5 (standard deviation= 9.1) years, and 467 participants were "not well-nourished," which was defined as having an MNA-T2 score of 23 or less. In the one-year study period, 659 participants reported having at least one fall. After adjusting for other risk factors, we found the associated odds ratio for falls was 1.73 (95% confidence interval, 1.23, 2.42) for "not well-nourished," 1.57 (1.30, 1.90) for female gender, 1.03 (1.02, 1.04) for one-year older, 1.55 (1.22, 1.98) for history of falls, 1.34 (1.05, 1.72) for hospital stay during the past 12 months, 1.66 (1.07, 2.58) for difficulties in activities of daily living, and 1.53 (1.23, 1.91) for difficulties in instrumental activities of daily living. Nutritional status is an independent predictor of falls in older people living in the community. Further studies are warranted to identify nutritional interventions that can help prevent falls in the elderly.

  4. Event detection using population-based health care databases in randomized clinical trials

    DEFF Research Database (Denmark)

    Thuesen, Leif; Jensen, Lisette Okkels; Tilsted, Hans Henrik

    2013-01-01

    To describe a new research tool, designed to reflect routine clinical practice and relying on population-based health care databases to detect clinical events in randomized clinical trials.......To describe a new research tool, designed to reflect routine clinical practice and relying on population-based health care databases to detect clinical events in randomized clinical trials....

  5. Scleroderma prevalence: demographic variations in a population-based sample.

    Science.gov (United States)

    Bernatsky, S; Joseph, L; Pineau, C A; Belisle, P; Hudson, M; Clarke, A E

    2009-03-15

    To estimate the prevalence of systemic sclerosis (SSc) using population-based administrative data, and to assess the sensitivity of case ascertainment approaches. We ascertained SSc cases from Quebec physician billing and hospitalization databases (covering approximately 7.5 million individuals). Three case definition algorithms were compared, and statistical methods accounting for imperfect case ascertainment were used to estimate SSc prevalence and case ascertainment sensitivity. A hierarchical Bayesian latent class regression model that accounted for possible between-test dependence conditional on disease status estimated the effect of patient characteristics on SSc prevalence and the sensitivity of the 3 ascertainment algorithms. Accounting for error inherent in both the billing and the hospitalization data, we estimated SSc prevalence in 2003 at 74.4 cases per 100,000 women (95% credible interval [95% CrI] 69.3-79.7) and 13.3 cases per 100,000 men (95% CrI 11.1-16.1). Prevalence was higher for older individuals, particularly in urban women (161.2 cases per 100,000, 95% CrI 148.6-175.0). Prevalence was lowest in young men (in rural areas, as low as 2.8 cases per 100,000, 95% CrI 1.4-4.8). In general, no single algorithm was very sensitive, with point estimates for sensitivity ranging from 20-73%. We found marked differences in SSc prevalence according to age, sex, and region. In general, no single case ascertainment approach was very sensitive for SSc. Therefore, using data from multiple sources, with adjustment for the imperfect nature of each, is an important strategy in population-based studies of SSc and similar conditions.

  6. Intimate Partner Violence and Depression in a Population-Based Sample of Women: Can Social Support Help?

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    Mburia-Mwalili, Adel; Clements-Nolle, Kristen; Lee, William; Shadley, Meri; Wei Yang,

    2010-01-01

    Data from the 2006 Behavioral Risk Factor Surveillance System in Nevada was analyzed to determine whether social support is independently associated with depression in a population-based sample of women with a history of intimate partner violence (IPV). More than a quarter (27%) of the women who were randomly chosen to participate in the survey…

  7. Genetic diversity of Kenyan Prosopis populations based on random ...

    African Journals Online (AJOL)

    MUTURI

    In combination, these traits may enhance the invasiveness of plant hybrids. The introduction of Prosopis ... Description of sample populations, plant sampling and reference species. Six naturally established Prosopis ...... boosted genetic diversity in the invasive range of black cherry. (Prunus serotina; Rosaceae). Ann. Bot.

  8. Sexual offender recidivism among a population-based prison sample.

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    Rettenberger, Martin; Briken, Peer; Turner, Daniel; Eher, Reinhard

    2015-04-01

    The present study examines recidivism rates in sexual offenders using officially registered reconvictions in a representative data set of N = 1,115 male sexual offenders from Austria. In general, results indicate that most sexual offenders do not reoffend sexually after release from prison. More detailed, within the first 5 years after release, the sexual recidivism rate was 6% for the total sample, 4% for the rapist subgroup, and 8% for the child molester subgroup. The findings confirmed previous studies about sex offender recidivism which have shown that first-time sexual offenders are significantly less likely to sexually reoffend than those with previous sexual convictions. With regard to the relationship between age and sexual recidivism, the results challenged the traditional assumption of a clear linear function between age and recidivism. Taken together, compared with previous studies, the recidivism rates found in the present investigation are substantially lower than previous research has indicated. © The Author(s) 2014.

  9. Gastrointestinal stromal tumors: treatment patterns of a population-based sample.

    Science.gov (United States)

    Harlan, Linda C; Eisenstein, Jana; Russell, Maria C; Stevens, Jennifer L; Cardona, Kenneth

    2015-05-01

    The National Cancer Institute (NCI) annually confirms therapy with treating physicians on a sample of patients diagnosed with a specific cancer. Using the NCI Patterns of Care data, treatment patterns were examined on a population-based sample of patients diagnosed with gastrointestinal stromal tumors (GIST) in 2008. A random sample of 323 of 405 GIST patients registered in SEER was selected. Most patients had gastric GISTs, were ≥ 65 years, white, had private insurance, and treated in a hospital with a residency program. Surgery was primarily performed in patients with non-metastatic disease (94%), in which: 26, 12, and 36% were at low, intermediate, and high-risk of recurrence, respectively. Amongst low-risk patients, ∼ 30% received adjuvant therapy. Amongst patients at higher risk, 26-40% did not receive adjuvant therapy. Imatinib was the most common targeted therapy administered. On multivariate analysis, age and risk-group were associated with receipt of adjuvant targeted therapy. Our study shows that in 2008, the majority of patients diagnosed with GIST received appropriate surgical and adjuvant therapies. However, a considerable subset may have been overtreated and undertreated. Future studies identifying factors that impact the delivery of adjuvant therapy should be conducted. © 2015 Wiley Periodicals, Inc.

  10. Parallel genetic algorithm with population-based sampling approach to discrete optimization under uncertainty

    Science.gov (United States)

    Subramanian, Nithya

    Optimization under uncertainty accounts for design variables and external parameters or factors with probabilistic distributions instead of fixed deterministic values; it enables problem formulations that might maximize or minimize an expected value while satisfying constraints using probabilities. For discrete optimization under uncertainty, a Monte Carlo Sampling (MCS) approach enables high-accuracy estimation of expectations but it also results in high computational expense. The Genetic Algorithm (GA) with a Population-Based Sampling (PBS) technique enables optimization under uncertainty with discrete variables at a lower computational expense than using Monte Carlo sampling for every fitness evaluation. Population-Based Sampling uses fewer samples in the exploratory phase of the GA and a larger number of samples when `good designs' start emerging over the generations. This sampling technique therefore reduces the computational effort spent on `poor designs' found in the initial phase of the algorithm. Parallel computation evaluates the expected value of the objective and constraints in parallel to facilitate reduced wall-clock time. A customized stopping criterion is also developed for the GA with Population-Based Sampling. The stopping criterion requires that the design with the minimum expected fitness value to have at least 99% constraint satisfaction and to have accumulated at least 10,000 samples. The average change in expected fitness values in the last ten consecutive generations is also monitored. The optimization of composite laminates using ply orientation angle as a discrete variable provides an example to demonstrate further developments of the GA with Population-Based Sampling for discrete optimization under uncertainty. The focus problem aims to reduce the expected weight of the composite laminate while treating the laminate's fiber volume fraction and externally applied loads as uncertain quantities following normal distributions. Construction of

  11. ADHD symptoms across the lifespan in a population-based Swedish sample aged 65 to 80.

    Science.gov (United States)

    Guldberg-Kjär, Taina; Sehlin, Sally; Johansson, Boo

    2013-04-01

    The purpose of the study was to examine the attention deficit hyperactivity disorder (ADHD) symptomatology across the lifespan by comparing older individuals' self-reports about current ADHD symptoms and symptoms in childhood. The 25-item Wender Utah Rating Scale (WURS) was initially administered in a population-based sample of 1,599 persons aged 65-80 years. We also asked about current health, memory, and problems in childhood. Based on their WURS scores (below and above 36), we randomly drew two subsamples, each with 30 individuals. They were followed up by the Wender Riktad ADHD Symtom Skala (WRASS)-scale, a Swedish version of the Targeted Attention Deficit Disorder Rating Scale (TADDS). Our main finding was that higher WURS scores were significantly related to higher scores on the WRASS scale, indicating persistence of self-reported ADHD symptoms over the whole lifespan. Among those with a WURS score of 36 or more, 16 (53.3%) individuals scored 70 or more; the clinical cut-off used in Sweden. None of the individuals with a WURS score below 36 scored higher than 70 on the WRASS scale. Our findings support the idea of a significant persistence of ADHD symptoms from childhood to old age. The results encourage studies of ADHD using a lifespan perspective, particularly in examining ADHD symptoms in old age.

  12. Psychological Abuse between Parents: Associations with Child Maltreatment from a Population-Based Sample

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    Chang, Jen Jen; Theodore, Adrea D.; Martin, Sandra L.; Runyan, Desmond K.

    2008-01-01

    Objective: This study examined the association between partner psychological abuse and child maltreatment perpetration. Methods: This cross-sectional study examined a population-based sample of mothers with children aged 0-17 years in North and South Carolina (n = 1,149). Mothers were asked about the occurrence of potentially neglectful or abusive…

  13. Analysis of family- and population-based samples in cohort genome-wide association studies.

    Science.gov (United States)

    Manichaikul, Ani; Chen, Wei-Min; Williams, Kayleen; Wong, Quenna; Sale, Michèle M; Pankow, James S; Tsai, Michael Y; Rotter, Jerome I; Rich, Stephen S; Mychaleckyj, Josyf C

    2012-02-01

    Cohort studies typically sample unrelated individuals from a population, although family members of index cases may also be recruited to investigate shared familial risk factors. Recruitment of family members may be incomplete or ancillary to the main cohort, resulting in a mixed sample of independent family units, including unrelated singletons and multiplex families. Multiple methods are available to perform genome-wide association (GWA) analysis of binary or continuous traits in families, but it is unclear whether methods known to perform well on ascertained pedigrees, sibships, or trios are appropriate in analysis of a mixed unrelated cohort and family sample. We present simulation studies based on Multi-Ethnic Study of Atherosclerosis (MESA) pedigree structures to compare the performance of several popular methods of GWA analysis for both quantitative and dichotomous traits in cohort studies. We evaluate approaches suitable for analysis of families, and combined the best performing methods with population-based samples either by meta-analysis, or by pooled analysis of family- and population-based samples (mega-analysis), comparing type 1 error and power. We further assess practical considerations, such as availability of software and ability to incorporate covariates in statistical modeling, and demonstrate our recommended approaches through quantitative and binary trait analysis of HDL cholesterol (HDL-C) in 2,553 MESA family- and population-based African-American samples. Our results suggest linear modeling approaches that accommodate family-induced phenotypic correlation (e.g., variance-component model for quantitative traits or generalized estimating equations for dichotomous traits) perform best in the context of combined family- and population-based cohort GWAS.

  14. On the Estimation of Heritability with Family-Based and Population-Based Samples

    Directory of Open Access Journals (Sweden)

    Youngdoe Kim

    2015-01-01

    Full Text Available For a family-based sample, the phenotypic variance-covariance matrix can be parameterized to include the variance of a polygenic effect that has then been estimated using a variance component analysis. However, with the advent of large-scale genomic data, the genetic relationship matrix (GRM can be estimated and can be utilized to parameterize the variance of a polygenic effect for population-based samples. Therefore narrow sense heritability, which is both population and trait specific, can be estimated with both population- and family-based samples. In this study we estimate heritability from both family-based and population-based samples, collected in Korea, and the heritability estimates from the pooled samples were, for height, 0.60; body mass index (BMI, 0.32; log-transformed triglycerides (log TG, 0.24; total cholesterol (TCHL, 0.30; high-density lipoprotein (HDL, 0.38; low-density lipoprotein (LDL, 0.29; systolic blood pressure (SBP, 0.23; and diastolic blood pressure (DBP, 0.24. Furthermore, we found differences in how heritability is estimated—in particular the amount of variance attributable to common environment in twins can be substantial—which indicates heritability estimates should be interpreted with caution.

  15. Disparities in sleep characteristics by race/ethnicity in a population-based sample: Chicago Area Sleep Study.

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    Carnethon, Mercedes R; De Chavez, Peter John; Zee, Phyllis C; Kim, Kwang-Youn A; Liu, Kiang; Goldberger, Jeffrey J; Ng, Jason; Knutson, Kristen L

    2016-02-01

    Prior studies report less favorable sleep characteristics among non-Whites as compared with non-Hispanic Whites. However, few population-based studies have used objective measures of sleep duration, especially in more than two racial/ethnic groups. We tested whether objectively estimated sleep duration and self-reported sleep quality varied by race and whether differences were at least partially explained by the variability in clinical, psychological, and behavioral covariates. Adults aged 35-64 years who self-identified as White, Black, Asian, or Hispanic were randomly sampled from Chicago, IL, and the surrounding suburbs. Our analytic sample included adults who had an apnea-hypopnea index sample of adults with a low probability of sleep apnea and following adjustment for known confounders. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Monthly fluctuations of insomnia symptoms in a population-based sample.

    Science.gov (United States)

    Morin, Charles M; Leblanc, M; Ivers, H; Bélanger, L; Mérette, Chantal; Savard, Josée; Jarrin, Denise C

    2014-02-01

    To document the monthly changes in sleep/insomnia status over a 12-month period; to determine the optimal time intervals to reliably capture new incident cases and recurrent episodes of insomnia and the likelihood of its persistence over time. Participants were 100 adults (mean age = 49.9 years; 66% women) randomly selected from a larger population-based sample enrolled in a longitudinal study of the natural history of insomnia. They completed 12 monthly telephone interviews assessing insomnia, use of sleep aids, stressful life events, and physical and mental health problems in the previous month. A total of 1,125 interviews of a potential 1,200 were completed. Based on data collected at each assessment, participants were classified into one of three subgroups: good sleepers, insomnia symptoms, and insomnia syndrome. At baseline, 42 participants were classified as good sleepers, 34 met criteria for insomnia symptoms, and 24 for an insomnia syndrome. There were significant fluctuations of insomnia over time, with 66% of the participants changing sleep status at least once over the 12 monthly assessments (51.5% for good sleepers, 59.5% for insomnia syndrome, and 93.4% for insomnia symptoms). Changes of status were more frequent among individuals with insomnia symptoms at baseline (mean = 3.46, SD = 2.36) than among those initially classified as good sleepers (mean = 2.12, SD = 2.70). Among the subgroup with insomnia symptoms at baseline, 88.3% reported improved sleep (i.e., became good sleepers) at least once over the 12 monthly assessments compared to 27.7% whose sleep worsened (i.e., met criteria for an insomnia syndrome) during the same period. Among individuals classified as good sleepers at baseline, risks of developing insomnia symptoms and syndrome over the subsequent months were, respectively, 48.6% and 14.5%. Monthly assessment over an interval of 6 months was found most reliable to estimate incidence rates, while an interval of 3 months proved the most

  17. Children's disclosures of sexual abuse in a population-based sample.

    Science.gov (United States)

    Lahtinen, Hanna-Mari; Laitila, Aarno; Korkman, Julia; Ellonen, Noora

    2018-02-01

    Most previous studies on disclosing child sexual abuse (CSA) have either been retrospective or focused on children who already have disclosed. The present study aimed to explore the overall CSA disclosure rate and factors associated with disclosing to adults in a large population-based sample. A representative sample of 11,364 sixth and ninth graders participated in the Finnish Child Victim Survey concerning experiences of violence, including CSA. CSA was defined as having sexual experiences with a person at least five years older at the time of the experience. Within this sample, the CSA prevalence was 2.4%. Children reporting CSA experiences also answered questions regarding disclosure, the disclosure recipient, and potential reasons for not disclosing. The results indicate that most of the children (80%) had disclosed to someone, usually a friend (48%). However, only 26% had disclosed to adults, and even fewer had reported their experiences to authorities (12%). The most common reason for non-disclosing was that the experience was not considered serious enough for reporting (41%), and half of the children having CSA experiences did not self-label their experiences as sexual abuse. Relatively few children reported lacking the courage to disclose (14%). Logistic regression analyses showed that the perpetrator's age, the age of the victim at the time of abuse, and having no experiences of emotional abuse by the mother were associated with disclosing to an adult. The results contribute to understanding the factors underlying children's disclosure patterns in a population-based sample and highlight the need for age-appropriate safety education for children and adolescents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Migraine and Mental Health in a Population-Based Sample of Adolescents.

    Science.gov (United States)

    Orr, Serena L; Potter, Beth K; Ma, Jinhui; Colman, Ian

    2017-01-01

    To explore the relationship between migraine and anxiety disorders, mood disorders and perceived mental health in a population-based sample of adolescents. The Canadian Community Health Survey (CCHS) is a cross-sectional health survey sampling a nationally representative group of Canadians. In this observational study, data on all 61,375 participants aged 12-19 years from six survey cycles were analyzed. The relationships between self-reported migraine, perceived mental health, and mood/anxiety disorders were modeled using univariate and multivariate logistic regression. The migraine-depression association was also explored in a subset of participants using the Composite International Diagnostic Interview-Short Form (CIDI-SF) depression scale. The odds of migraine were higher among those with mood disorders, with the strongest association in 2011-2 (adjusted odds ratio [aOR]=4.59; 95% confidence interval [CI 95%]=3.44-6.12), and the weakest in 2009-10 (aOR=3.06, CI 95%=2.06-4.55). The migraine-mood disorders association was also significant throughout all cycles, other than 2011-2, when the CIDI-SF depression scale was employed. The odds of migraine were higher among those with anxiety disorders, with the strongest association in 2011-2 (aOR=4.21, CI 95%=3.31-5.35) and the weakest in 2010 (aOR=1.87, CI 95%=1.10-3.37). The inverse association between high perceived mental health and the odds of migraine was observed in all CCHS cycles, with the strongest association in 2011-2 (aOR=0.58, CI 95%=0.48-0.69) and the weakest in 2003-4 (aOR=0.75, CI 95%=0.62-0.91). This study provides evidence, derived from a large population-based sample of adolescents, for a link between migraine and mood/anxiety disorders.

  19. Predicting sexual infidelity in a population-based sample of married individuals.

    Science.gov (United States)

    Whisman, Mark A; Gordon, Kristina Coop; Chatav, Yael

    2007-06-01

    Predictors of 12-month prevalence of sexual infidelity were examined in a population-based sample of married individuals (N = 2,291). Predictor variables were organized in terms of involved-partner (e.g., personality, religiosity), marital (e.g., marital dissatisfaction, partner affair), and extradyadic (e.g., parenting) variables. Annual prevalence of infidelity was 2.3%. Controlling for marital dissatisfaction and demographic variables, infidelity was predicted by greater neuroticism and lower religiosity; wives' pregnancy also increased the risk of infidelity for husbands. In comparison, self-esteem and partners' suspected affair were predictive of infidelity when controlling for demographic variables but were not uniquely predictive of infidelity when also controlling for marital dissatisfaction. Religiosity and wives' pregnancy moderated the association between marital dissatisfaction and infidelity.

  20. Infertility treatment in a population-based sample: 2004-2005.

    Science.gov (United States)

    Simonsen, Sara E; Baksh, Laurie; Stanford, Joseph B

    2012-05-01

    To describe the characteristics of women seeking infertility treatment and the types of fertility treatment sought within a population-based sample. We analyzed data from the cross-sectional Pregnancy Risk Assessment Monitoring System (PRAMS) of women with a live birth using data from seven states. Logistic regression was used to determine factors associated with infertility treatment utilization. Infertility treatment was reported by 10.5% of women who were trying to become pregnant. The most common treatment reported was fertility enhancing drugs (29%), followed by assisted reproductive technology including in vitro fertilization (21%), and artificial insemination together with fertility enhancing drugs (15%). Some women reported using other types of treatment (23%). The PRAMS data provide insights into the use of infertility treatment among women giving birth in the United States. Further research is needed to understand the true prevalence of infertility, factors that influence treatment choices, and the longitudinal impact of infertility treatment on outcomes.

  1. The interrelation between premenstrual syndrome and major depression: Results from a population-based sample

    Directory of Open Access Journals (Sweden)

    Weiss Carine

    2011-10-01

    Full Text Available Abstract Background Research about the relationship between premenstrual syndrome (PMS and major depression is limited. This study examined the relationship between moderate to severe PMS and major depression in a population-based sample of women of reproductive age. The objectives of the study were to assess the association between premenstrual syndrome and major depression, to analyse how PMS and major depression differ and to characterise the group of women who report both PMS and major depression. Methods Data were obtained from the Swiss Health Survey 2007. Included in the analysis was data from women under the age of 55 without hysterectomy and who answered the questions on PMS symptoms. The population-based sample consisted of 3518 women. Weighted prevalence rates were calculated and relative risk ratios for PMS, major depression and women who reported both PMS and major depression, were calculated with logistic multinominal logit regression. Results The prevalence of major depression was 11.3% in women screening positive for moderate PMS and 24.6% in women screening positive for severe PMS. Compared to women without any of these conditions, women who reported moderate to severe alcohol consumption had a lower risk for PMS. Women reporting use of antidepressants, and use of oral contraceptives had a higher risk for major depression compared to women without any of these conditions. Women reporting work dissatisfaction had a higher risk for PMS. A higher relative risk to report both PMS and major depression compared to women without PMS or major depression was related to factors such as high psychological distress, low mastery, psychotropic drug consumption, and low self-rated health. Conclusions The results suggested that women who suffer from both PMS and major depression are more impaired compared to women with only one disorder. The results further indicated that PMS and major depression are different disorders that can, however, co-occur.

  2. Predicting brain structure in population-based samples with biologically informed genetic scores for schizophrenia.

    Science.gov (United States)

    Van der Auwera, Sandra; Wittfeld, Katharina; Shumskaya, Elena; Bralten, Janita; Zwiers, Marcel P; Onnink, A Marten H; Usberti, Niccolo; Hertel, Johannes; Völzke, Henry; Völker, Uwe; Hosten, Norbert; Franke, Barbara; Grabe, Hans J

    2017-04-01

    Schizophrenia is associated with brain structural abnormalities including gray and white matter volume reductions. Whether these alterations are caused by genetic risk variants for schizophrenia is unclear. Previous attempts to detect associations between polygenic factors for schizophrenia and structural brain phenotypes in healthy subjects have been negative or remain non-replicated. In this study, we used genetic risk scores that were based on the accumulated effect of selected risk variants for schizophrenia belonging to specific biological systems like synaptic function, neurodevelopment, calcium signaling, and glutamatergic neurotransmission. We hypothesized that this "biologically informed" approach would provide the missing link between genetic risk for schizophrenia and brain structural phenotypes. We applied whole-brain voxel-based morphometry (VBM) analyses in two population-based target samples and subsequent regions of interest (ROIs) analyses in an independent replication sample (total N = 2725). No consistent association between the genetic scores and brain volumes were observed in the investigated samples. These results suggest that in healthy subjects with a higher genetic risk for schizophrenia additional factors apart from common genetic variants (e.g., infection, trauma, rare genetic variants, or gene-gene interactions) are required to induce structural abnormalities of the brain. Further studies are recommended to test for possible gene-gene or gene-environment effects. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  3. The relation between exercise and glaucoma in a South Korean population-based sample.

    Science.gov (United States)

    Lin, Shuai-Chun; Wang, Sophia Y; Pasquale, Louis R; Singh, Kuldev; Lin, Shan C

    2017-01-01

    To investigate the association between exercise and glaucoma in a South Korean population-based sample. Population-based, cross-sectional study. A total of 11,246 subjects, 40 years and older who underwent health care assessment as part of the 2008-2011 Korean National Health and Nutrition Examination Survey. Variables regarding the duration (total minutes per week), frequency (days per week), and intensity of exercise (vigorous, moderate exercise and walking) as well as glaucoma prevalence were ascertained for 11,246 survey participants. Demographic, comorbidity, and health-related behavior information was obtained via interview. Multivariable logistic regression analyses were performed to determine the association between the exercise-related parameters and odds of a glaucoma diagnosis. Glaucoma defined by International Society for Geographical and Epidemiological Ophthalmology criteria. Overall, 336 (2.7%) subjects met diagnostic criteria for glaucomatous disease. After adjustment for potential confounding variables, subjects engaged in vigorous exercise 7 days per week had higher odds of having glaucoma compared with those exercising 3 days per week (Odds Ratio [OR] 3.33, 95% confidence interval [CI] 1.16-9.54). High intensity of exercise, as categorized by the guidelines of the American College of Sports Medicine (ACSM), was also associated with greater glaucoma prevalence compared with moderate intensity of exercise (OR 1.55, 95% CI 1.03-2.33). There was no association between other exercise parameters including frequency of moderate exercise, walking, muscle strength exercise, flexibility training, or total minutes of exercise per week, and the prevalence of glaucoma. In sub-analyses stratifying by gender, the association between frequency of vigorous exercise 7 days per week and glaucoma diagnosis remained significant in men (OR 6.05, 95% CI 1.67-21.94) but not in women (OR 0.96 95% CI: 0.23-3.97). A U-shaped association between exercise intensity and

  4. The relation between exercise and glaucoma in a South Korean population-based sample.

    Directory of Open Access Journals (Sweden)

    Shuai-Chun Lin

    Full Text Available To investigate the association between exercise and glaucoma in a South Korean population-based sample.Population-based, cross-sectional study.A total of 11,246 subjects, 40 years and older who underwent health care assessment as part of the 2008-2011 Korean National Health and Nutrition Examination Survey.Variables regarding the duration (total minutes per week, frequency (days per week, and intensity of exercise (vigorous, moderate exercise and walking as well as glaucoma prevalence were ascertained for 11,246 survey participants. Demographic, comorbidity, and health-related behavior information was obtained via interview. Multivariable logistic regression analyses were performed to determine the association between the exercise-related parameters and odds of a glaucoma diagnosis.Glaucoma defined by International Society for Geographical and Epidemiological Ophthalmology criteria.Overall, 336 (2.7% subjects met diagnostic criteria for glaucomatous disease. After adjustment for potential confounding variables, subjects engaged in vigorous exercise 7 days per week had higher odds of having glaucoma compared with those exercising 3 days per week (Odds Ratio [OR] 3.33, 95% confidence interval [CI] 1.16-9.54. High intensity of exercise, as categorized by the guidelines of the American College of Sports Medicine (ACSM, was also associated with greater glaucoma prevalence compared with moderate intensity of exercise (OR 1.55, 95% CI 1.03-2.33. There was no association between other exercise parameters including frequency of moderate exercise, walking, muscle strength exercise, flexibility training, or total minutes of exercise per week, and the prevalence of glaucoma. In sub-analyses stratifying by gender, the association between frequency of vigorous exercise 7 days per week and glaucoma diagnosis remained significant in men (OR 6.05, 95% CI 1.67-21.94 but not in women (OR 0.96 95% CI: 0.23-3.97. A U-shaped association between exercise intensity and

  5. Sampling methodology and site selection in the National Eye Health Survey: an Australian population-based prevalence study.

    Science.gov (United States)

    Foreman, Joshua; Keel, Stuart; Dunn, Ross; van Wijngaarden, Peter; Taylor, Hugh R; Dirani, Mohamed

    2017-05-01

    This paper presents the sampling methodology of the National Eye Health Survey that aimed to determine the prevalence of vision impairment and blindness in Australia. The National Eye Health Survey is a cross-sectional population-based survey. Indigenous Australians aged 40 years and older and non-Indigenous Australians aged 50 years and older residing in all levels of geographic remoteness in Australia. Using multistage, random-cluster sampling, 30 geographic areas were selected to provide samples of 3000 non-Indigenous Australians and 1400 Indigenous Australians. Sampling involved (i) selecting Statistical Area- Level 2 sites, stratified by remoteness; (ii) selecting Statistical Area- Level 1 sites within Statistical Area- Level 2 sites to provide targeted samples; and (iii) grouping of contiguous Statistical Area- Level 1 sites or replacing Statistical Area- Level 1 sites to provide sufficient samples. The main outcome measures involved Sites sites selected and participants sampled in the survey. Thirty sites were generated, including 12 Major City sites, 6 Inner Regional sites, 6 Outer Regional sites, 4 Remote sites and 2 Very Remote sites. Three thousand ninety-eight non-Indigenous participants and 1738 Indigenous participants were recruited. Selection of Statistical Area- Level 1 site overestimated the number of eligible residents in all sites. About 20% (6/30) of Statistical Area- Level 1 sites were situated in non-residential bushland, and 26.67% (8/30) of Statistical Area- Level 1 populations had low eligibility or accessibility, requiring replacement. Representative samples of Indigenous and non-Indigenous Australians were selected, recruited and tested, providing the first national data on the prevalence of vision impairment and blindness in Australia. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

  6. Predicting Successful Aging in a Population-Based Sample of Georgia Centenarians

    Directory of Open Access Journals (Sweden)

    Jonathan Arnold

    2010-01-01

    Full Text Available Used a population-based sample (Georgia Centenarian Study, GCS, to determine proportions of centenarians reaching 100 years as (1 survivors (43% of chronic diseases first experienced between 0–80 years of age, (2 delayers (36% with chronic diseases first experienced between 80–98 years of age, or (3 escapers (17% with chronic diseases only at 98 years of age or older. Diseases fall into two morbidity profiles of 11 chronic diseases; one including cardiovascular disease, cancer, anemia, and osteoporosis, and another including dementia. Centenarians at risk for cancer in their lifetime tended to be escapers (73%, while those at risk for cardiovascular disease tended to be survivors (24%, delayers (39%, or escapers (32%. Approximately half (43% of the centenarians did not experience dementia. Psychiatric disorders were positively associated with dementia, but prevalence of depression, anxiety, and psychoses did not differ significantly between centenarians and an octogenarian control group. However, centenarians were higher on the Geriatric Depression Scale (GDS than octogenarians. Consistent with our model of developmental adaptation in aging, distal life events contribute to predicting survivorship outcome in which health status as survivor, delayer, or escaper appears as adaptation variables late in life.

  7. Predicting successful aging in a population-based sample of georgia centenarians.

    Science.gov (United States)

    Arnold, Jonathan; Dai, Jianliang; Nahapetyan, Lusine; Arte, Ankit; Johnson, Mary Ann; Hausman, Dorothy; Rodgers, Willard L; Hensley, Robert; Martin, Peter; Macdonald, Maurice; Davey, Adam; Siegler, Ilene C; Jazwinski, S Michal; Poon, Leonard W

    2010-01-01

    Used a population-based sample (Georgia Centenarian Study, GCS), to determine proportions of centenarians reaching 100 years as (1) survivors (43%) of chronic diseases first experienced between 0-80 years of age, (2) delayers (36%) with chronic diseases first experienced between 80-98 years of age, or (3) escapers (17%) with chronic diseases only at 98 years of age or older. Diseases fall into two morbidity profiles of 11 chronic diseases; one including cardiovascular disease, cancer, anemia, and osteoporosis, and another including dementia. Centenarians at risk for cancer in their lifetime tended to be escapers (73%), while those at risk for cardiovascular disease tended to be survivors (24%), delayers (39%), or escapers (32%). Approximately half (43%) of the centenarians did not experience dementia. Psychiatric disorders were positively associated with dementia, but prevalence of depression, anxiety, and psychoses did not differ significantly between centenarians and an octogenarian control group. However, centenarians were higher on the Geriatric Depression Scale (GDS) than octogenarians. Consistent with our model of developmental adaptation in aging, distal life events contribute to predicting survivorship outcome in which health status as survivor, delayer, or escaper appears as adaptation variables late in life.

  8. Predicting Successful Aging in a Population-Based Sample of Georgia Centenarians

    Science.gov (United States)

    Arnold, Jonathan; Dai, Jianliang; Nahapetyan, Lusine; Arte, Ankit; Johnson, Mary Ann; Hausman, Dorothy; Rodgers, Willard L.; Hensley, Robert; Martin, Peter; MacDonald, Maurice; Davey, Adam; Siegler, Ilene C.; Jazwinski, S. Michal; Poon, Leonard W.

    2010-01-01

    Used a population-based sample (Georgia Centenarian Study, GCS), to determine proportions of centenarians reaching 100 years as (1) survivors (43%) of chronic diseases first experienced between 0–80 years of age, (2) delayers (36%) with chronic diseases first experienced between 80–98 years of age, or (3) escapers (17%) with chronic diseases only at 98 years of age or older. Diseases fall into two morbidity profiles of 11 chronic diseases; one including cardiovascular disease, cancer, anemia, and osteoporosis, and another including dementia. Centenarians at risk for cancer in their lifetime tended to be escapers (73%), while those at risk for cardiovascular disease tended to be survivors (24%), delayers (39%), or escapers (32%). Approximately half (43%) of the centenarians did not experience dementia. Psychiatric disorders were positively associated with dementia, but prevalence of depression, anxiety, and psychoses did not differ significantly between centenarians and an octogenarian control group. However, centenarians were higher on the Geriatric Depression Scale (GDS) than octogenarians. Consistent with our model of developmental adaptation in aging, distal life events contribute to predicting survivorship outcome in which health status as survivor, delayer, or escaper appears as adaptation variables late in life. PMID:20885919

  9. Food insecurity and dyslipidemia in a representative population-based sample in the US.

    Science.gov (United States)

    Shin, Jung-Im; Bautista, Leonelo E; Walsh, Matthew C; Malecki, Kristen C; Nieto, F Javier

    2015-08-01

    The association of food insecurity with dyslipidemia has not been firmly established. The main objective of this study was to assess whether food insecurity was associated with dyslipidemia. A population-based sample of 1,663 adults from the 2008-2011 Survey of the Health of Wisconsin was used. Food insecurity was defined as an affirmative response to either of the questions: (1) "In the last 12months, have you been concerned about having enough food for you or your family?" (2) "In the last 12months, have your food choices been limited because there wasn't enough money?" High total cholesterol was defined as total cholesterol (TC) >240mg/dL or taking prescribed lipid-lowering medication. Low high-density lipoprotein cholesterol (HDL-C) was defined as Obesity appears to be a partial mediator of the association among women (P from the Sobel test=0.01). These findings suggest that food insecurity may contribute to an increased risk of low HDL-C in women. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. A genome-wide association study of neuroticism in a population-based sample.

    Directory of Open Access Journals (Sweden)

    Federico C F Calboli

    Full Text Available Neuroticism is a moderately heritable personality trait considered to be a risk factor for developing major depression, anxiety disorders and dementia. We performed a genome-wide association study in 2,235 participants drawn from a population-based study of neuroticism, making this the largest association study for neuroticism to date. Neuroticism was measured by the Eysenck Personality Questionnaire. After Quality Control, we analysed 430,000 autosomal SNPs together with an additional 1.2 million SNPs imputed with high quality from the Hap Map CEU samples. We found a very small effect of population stratification, corrected using one principal component, and some cryptic kinship that required no correction. NKAIN2 showed suggestive evidence of association with neuroticism as a main effect (p < 10(-6 and GPC6 showed suggestive evidence for interaction with age (p approximately = 10(-7. We found support for one previously-reported association (PDE4D, but failed to replicate other recent reports. These results suggest common SNP variation does not strongly influence neuroticism. Our study was powered to detect almost all SNPs explaining at least 2% of heritability, and so our results effectively exclude the existence of loci having a major effect on neuroticism.

  11. Dimensionality of stress experiences: Factorial structure of the Perceived Stress Questionnaire (PSQ) in a population-based Swedish sample.

    Science.gov (United States)

    Rönnlund, Michael; Vestergren, Peter; Stenling, Andreas; Nilsson, Lars-Göran; Bergdahl, Maud; Bergdahl, Jan

    2015-10-01

    We investigated the factorial structure of the Perceived Stress Questionnaire (PSQ-recent; Levenstein, Prantera, Varvo et al., 1993) in a large (N = 1516; 35-95 years) population-based Swedish sample (Nilsson, Adolfsson, Bäckman et al., 2004; Nilsson, Bäckman, Erngrund et al., 1997). Exploratory principal components analysis (PCA) was conducted on a first, randomly drawn subsample (n = 506). Next, the model based on the PCA was tested in a second sample (n = 505). Finally, a third sample (n = 505) was used to cross-validate the model. Five components were extracted in the PCA (eigenvalue > 1) and labeled "Demands," "Worries/Tension," "Lack of joy," "Conflict," and "Fatigue," respectively. Twenty-one out of the 30 original PSQ items were retained in a confirmatory factor analysis (CFA) model that included the five (first-order) factors and, additionally, a general (second-order) stress factor, not considered in prior models. The model showed reasonable goodness of fit [χ(2)(184) = 511.2, p factor analyses supported the validity of the established model. The results are discussed in relation to prior investigations of the factorial structure of the PSQ. © 2015 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  12. The association between dispositional mindfulness, psychological well-being, and perceived health in a Swedish population-based sample.

    Science.gov (United States)

    Bränström, Richard; Duncan, Larissa G; Moskowitz, Judith Tedlie

    2011-05-01

    There is increasing recognition of the links between mindfulness, decreased stress, and healthier psychological functioning. However, the majority of this research has been conducted in US samples and the mechanisms through which mindfulness decreases stress and increases well-being are not well understood. The aim of this study was to examine the relations between mindfulness and psychological functioning in a general population sample in Sweden. This cross-sectional study examined the association of mindfulness and five subscales of mindfulness with depression, anxiety, positive states of mind (PSOM), and perceived health. In the spring of 2007, a random population-based sample of N= 1,000 individuals aged 18-60 years in Sweden was contacted by mail with a request to participate in the study. Mindfulness and some of its subscales, in particular Acting with awareness and Non-reactivity to inner experiences, were strongly related to PSOM and perceived health, and inversely related to depression and anxiety. Tests of the moderating role of mindfulness showed that the associations of perceived stress with depression and perceived health were diminished for those with higher levels of mindfulness. Mindfulness is strongly related to well-being and perceived health. Results suggest that dispositional mindfulness might buffer against the negative influence of perceived stress on psychological well-being. These findings give additional support for the use of mindfulness training as a way of improving psychological functioning among people experiencing stress. ©2010 The British Psychological Society.

  13. Adverse childhood experiences, gender, and HIV risk behaviors: Results from a population-based sample

    Directory of Open Access Journals (Sweden)

    Lin Fang

    2016-12-01

    Full Text Available Recent HIV research suggested assessing adverse childhood experiences (ACEs as contributing factors of HIV risk behaviors. However, studies often focused on a single type of adverse experience and very few utilized population-based data. This population study examined the associations between ACE (individual and cumulative ACE score and HIV risk behaviors. We analyzed the 2012 Behavioral Risk Factor Surveillance Survey (BRFSS from 5 states. The sample consisted of 39,434 adults. Eight types of ACEs that included different types of child abuse and household dysfunctions before the age of 18 were measured. A cumulative score of ACEs was also computed. Logistic regression estimated of the association between ACEs and HIV risk behaviors using odds ratio (OR with 95% confidence intervals (CIs for males and females separately. We found that ACEs were positively associated with HIV risk behaviors overall, but the associations differed between males and females in a few instances. While the cumulative ACE score was associated with HIV risk behaviors in a stepwise manner, the pattern varied by gender. For males, the odds of HIV risk increased at a significant level as long as they experienced one ACE, whereas for females, the odds did not increase until they experienced three or more ACEs. Future research should further investigate the gender-specific associations between ACEs and HIV risk behaviors. As childhood adversities are prevalent among general population, and such experiences are associated with increased risk behaviors for HIV transmission, service providers can benefit from the principles of trauma-informed practice.

  14. Characterization of mitochondrial haplogroups in a large population-based sample from the United States.

    Science.gov (United States)

    Mitchell, Sabrina L; Goodloe, Robert; Brown-Gentry, Kristin; Pendergrass, Sarah A; Murdock, Deborah G; Crawford, Dana C

    2014-07-01

    Mitochondrial DNA (mtDNA) haplogroups are valuable for investigations in forensic science, molecular anthropology, and human genetics. In this study, we developed a custom panel of 61 mtDNA markers for high-throughput classification of European, African, and Native American/Asian mitochondrial haplogroup lineages. Using these mtDNA markers, we constructed a mitochondrial haplogroup classification tree and classified 18,832 participants from the National Health and Nutrition Examination Surveys (NHANES). To our knowledge, this is the largest study to date characterizing mitochondrial haplogroups in a population-based sample from the United States, and the first study characterizing mitochondrial haplogroup distributions in self-identified Mexican Americans separately from Hispanic Americans of other descent. We observed clear differences in the distribution of maternal genetic ancestry consistent with proposed admixture models for these subpopulations, underscoring the genetic heterogeneity of the United States Hispanic population. The mitochondrial haplogroup distributions in the other self-identified racial/ethnic groups within NHANES were largely comparable to previous studies. Mitochondrial haplogroup classification was highly concordant with self-identified race/ethnicity (SIRE) in non-Hispanic whites (94.8 %), but was considerably lower in admixed populations including non-Hispanic blacks (88.3 %), Mexican Americans (81.8 %), and other Hispanics (61.6 %), suggesting SIRE does not accurately reflect maternal genetic ancestry, particularly in populations with greater proportions of admixture. Thus, it is important to consider inconsistencies between SIRE and genetic ancestry when performing genetic association studies. The mitochondrial haplogroup data that we have generated, coupled with the epidemiologic variables in NHANES, is a valuable resource for future studies investigating the contribution of mtDNA variation to human health and disease.

  15. Weapon carrying and psychopathic-like features in a population-based sample of Finnish adolescents.

    Science.gov (United States)

    Saukkonen, Suvi; Laajasalo, Taina; Jokela, Markus; Kivivuori, Janne; Salmi, Venla; Aronen, Eeva T

    2016-02-01

    We investigated the prevalence of juvenile weapon carrying and psychosocial and personality-related risk factors for carrying different types of weapons in a nationally representative, population-based sample of Finnish adolescents. Specifically, we aimed to investigate psychopathic-like personality features as a risk factor for weapon carrying. The participants were 15-16-year-old adolescents from the Finnish self-report delinquency study (n = 4855). Four different groups were formed based on self-reported weapon carrying: no weapon carrying, carrying knife, gun or other weapon. The associations between psychosocial factors, psychopathic-like features and weapon carrying were examined with multinomial logistic regression analysis. 9% of the participants had carried a weapon in the past 12 months. Adolescents with a history of delinquency, victimization and antisocial friends were more likely to carry weapons in general; however, delinquency and victimization were most strongly related to gun carrying, while perceived peer delinquency (antisocial friends) was most strongly related to carrying a knife. Better academic performance was associated with a reduced likelihood of carrying a gun and knife, while feeling secure correlated with a reduced likelihood of gun carrying only. Psychopathic-like features were related to a higher likelihood of weapon carrying, even after adjusting for other risk factors. The findings of the study suggest that adolescents carrying a weapon have a large cluster of problems in their lives, which may vary based on the type of weapon carried. Furthermore, psychopathic-like features strongly relate to a higher risk of carrying a weapon.

  16. Association of cardiometabolic risk factors and dental caries in a population-based sample of youths

    Directory of Open Access Journals (Sweden)

    Kelishadi Roya

    2010-04-01

    Full Text Available Abstract Background Cardiovascular disease (CVD risk factors begin from early life and track onto adulthood. Oral and dental diseases share some risk factors with CVD, therefore by finding a clear relation between dental diseases and cardiometabolic risk factors; we can then predict the potential risk of one based on the presence of the other. This study aimed to compare the prevalence of dental caries between two groups of age-matched adolescents with and without CVD risk factors. Methods In this case-control study, the decayed, missing and filled surfaces (DMFS, based on the criteria of the World Health Organization, were compared in two groups of equal number (n = 61 in each group of population-based sample of adolescents with and without CVD risk factors who were matched for sex and age group. Results The study participants had a median age 13 y 5 mo, age range 11 y 7 mo to 16 y 1 mo, with male-to-female proportion of 49/51. We found significant difference between the mean values of DMFS, body mass index, waist and hip circumferences, as well as serum lipid profile in the case and control groups. Significant correlations were documented for DMFS with TC (r = 0.54, p = 0.02, LDL-C (r = 0.55, p = 0.01 and TG (r = 0.52, p = 0.04 in the case group; with LDL-C (r = 0.47, p = 0.03 in the whole study participants and with TC in control s(r = 0.45, p = 0.04. Conclusions Given the significant associations between dental caries and CVD risk factors among adolescents, more attention should be paid to oral health, as one of the topics to be taken into account in primordial/primary prevention of cardiometabolic disorders.

  17. Infertility and subfecundity in population-based samples from Denmark, Germany, Italy, Poland and Spain

    DEFF Research Database (Denmark)

    Karmaus, Wilfried; Juul, Svend

    1999-01-01

    Background: No uniform data which give basic Information on the societal burden of infertility and subfecundity exists in Europe. Methods: In a population-based survey the prevalence of subfecundity was ascertained by means of a standardized interview with women in Denmark, Germany, Poland, Italy...

  18. Apolipoprotein E phenotype is not related to late-life depression in a population-based sample

    NARCIS (Netherlands)

    Schmand, B.; Hooijer, C.; Jonker, C.; Lindeboom, J.; Havekes, L.M.

    1998-01-01

    Apolipoprotein E (ApoE) allele frequencies were examined in a population-based sample (n = 475; age range 65-84 years; Amsterdam Study of the Elderly). The relation of ApoE ε4 with dementia and with various types of late-life depression was studied. Depression was measured with the Geriatric Mental

  19. Men's and Women's Health Beliefs Differentially Predict Coronary Heart Disease Incidence in a Population-Based Sample

    Science.gov (United States)

    Korin, Maya Rom; Chaplin, William F.; Shaffer, Jonathan A.; Butler, Mark J.; Ojie, Mary-Jane; Davidson, Karina W.

    2013-01-01

    Objective: To examine gender differences in the association between beliefs in heart disease preventability and 10-year incidence of coronary heart disease (CHD) in a population-based sample. Methods: A total of 2,688 Noninstitutionalized Nova Scotians without prior CHD enrolled in the Nova Scotia Health Study (NSHS95) and were followed for 10…

  20. Passive Range of Motion in a Population-Based Sample of Children with Spastic Cerebral Palsy Who Walk

    Science.gov (United States)

    McDowell, Brona C.; Salazar-Torres, Jose J.; Kerr, Claire; Cosgrove, Aidan P.

    2012-01-01

    -While passive range of motion (PROM) is commonly used to inform decisions on therapeutic management, knowledge of PROM of children with spastic cerebral palsy (CP) is limited. A population-based sample of 178 children with spastic CP (110 male; unilateral, n = 94; bilateral, n = 84; age range 4-17 years) and 68 typically developing children (24…

  1. "Hardcore" definitions and their application to a population-based sample of smokers.

    Science.gov (United States)

    Costa, Michelle L; Cohen, Joanna E; Chaiton, Michael O; Ip, David; McDonald, Paul; Ferrence, Roberta

    2010-08-01

    As smoking prevalence declines, some suggest that so-called "hardcore" smokers will come to represent a growing and irreducible proportion of current smokers ("hardening hypothesis"). Different definitions of a "hardcore" smoker have been used in the literature. This paper describes population-based definitions of "hardcore" smokers and compares estimates of the prevalence of "hardcore" smokers derived using these definitions. Definitions identified in a comprehensive literature search were reduced to their component constructs. We estimated the prevalence of "hardcore" smokers as a proportion of all current adult smokers in Ontario, Canada, using data from the Ontario Tobacco Survey (2005-2008; N = 4,130). Definition concordance was examined using bivariate cross-tabulations. Six definitions were identified in the literature. Five definitions included constructs of quit intentions and quit attempts, four included nicotine dependence, three included long-term use, and one included a measure of smoker knowledge about smoking hazards and confronting substantial societal disapprobation of smoking. Estimates of "hardcore" smoker prevalence in Ontario based on these definitions ranged from 0.03% to 13.77%. Estimates of the prevalence of "hardcore" smokers in Ontario varied considerably between the six definitions of the "hardcore" smokers found in the population-based literature. This study underscores the need for consensus on the best definition of "hardcore" smoker.

  2. Tolerable rates of visual field progression in a population-based sample of patients with glaucoma.

    Science.gov (United States)

    Salonikiou, Angeliki; Founti, Panayiota; Kilintzis, Vassilis; Antoniadis, Antonis; Anastasopoulos, Eleftherios; Pappas, Theofanis; Raptou, Anastasia; Topouzis, Fotis

    2017-09-28

    To provide population-based data on the maximum tolerable rate of progression to avoid visual impairment (maxTRoP_VI) and blindness (maxTRoP_BL) from open-angle glaucoma (OAG). Participants with OAG in the Thessaloniki Eye Study (cross-sectional, population-based study in a European population) were included in the analysis. Visual impairment was defined as mean deviation (MD) equal to or worse than -12 dB and blindness as MD equal to or worse than -24 dB. Additional thresholds for visual impairment were tested. For each participant maxTRoP_VI was defined as the rate of progression which would not lead to visual impairment during expected lifetime. MaxTRoP_BL was defined accordingly. Both parameters were calculated for each OAG subject using age, sex, MD and life expectancy data. The eye with the better MD per subject was included in the analysis. Among 135 subjects with OAG, 123 had reliable visual fields and were included in the analysis. The mean age was 73±6 years and the median MD was -3.65±5.28 dB. Among those, 69.1% would have a maxTRoP_VI slower than -1 dB/year and 18.7% would have a maxTRoP_VI between -1 and -2 dB/year. Also, 72.4% would have a maxTRoP_BL slower than -2 dB/year. For all tested thresholds for visual impairment, approximately 86% of the OAG study participants would not be able to tolerate a rate of progression equal to or faster than -2 dB/year. The majority of patients with glaucoma in our study would have a maximum tolerable rate of progression slower than -1 dB/year in their better eye. Patient-tailored strategies to monitor the visual field are important, but raise the issue of feasibility with regard to the number of visual field tests needed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  3. Intimate Partner Violence and Gestational Weight Gain in a Population-Based Sample of Perinatal Women.

    Science.gov (United States)

    Alhusen, Jeanne L; Geller, Ruth; Dreisbach, Caitlin; Constantoulakis, Leeza; Siega-Riz, Anna Maria

    To examine the effects of intimate partner violence (IPV) at varied time points in the perinatal period on inadequate and excessive gestational weight gain. Retrospective cohort using population-based secondary data. Pregnancy Risk Assessment Monitoring System and birth certificate data from New York City and 35 states. Data were obtained for 251,342 U.S. mothers who gave birth from 2004 through 2011 and completed the Pregnancy Risk Assessment Monitoring System survey 2 to 9 months after birth. The exposure was perinatal IPV, defined as experiencing physical abuse by a current or ex-partner in the year before or during pregnancy. Adequacy of gestational weight gain (GWG) was categorized using 2009 Institute of Medicine guidelines. Weighted descriptive statistics and multivariate logistic regression models were used. Approximately 6% of participants reported perinatal IPV, 2.7% reported IPV in the year before pregnancy, 1.1% reported IPV during pregnancy only, and the remaining 2.5% reported IPV before and during pregnancy. Inadequate GWG was more prevalent among participants who experienced IPV during pregnancy and those who experienced IPV before and during pregnancy (23.3% and 23.5%, respectively) than in participants who reported no IPV (20.2%; p modeling; only participants who experienced IPV before pregnancy had weakly significant odds of excessive GWG (adjusted odds ratio = 1.14, 95% CI [1.02, 1.26]). The association between perinatal IPV and inadequate GWG was explained by confounding variables; however, women who reported perinatal IPV had greater rates of GWG outside the optimal range. Future studies are needed to determine how relevant confounding variables may affect a woman's GWG. Copyright © 2017 AWHONN, the Association of Women’s Health, Obstetric and Neonatal Nurses. Published by Elsevier Inc. All rights reserved.

  4. Psychotic Experiences and Neuropsychological Functioning in a Population-based Sample.

    Science.gov (United States)

    Mollon, Josephine; David, Anthony S; Morgan, Craig; Frissa, Souci; Glahn, David; Pilecka, Izabela; Hatch, Stephani L; Hotopf, Matthew; Reichenberg, Abraham

    2016-02-01

    Psychotic experiences in early life are associated with neuropsychological impairment and the risk for later psychiatric disorders. Psychotic experiences are also prevalent in adults, but neuropsychological investigations spanning adulthood are limited, and confounding factors have not been examined rigorously. To characterize neuropsychological functioning in adults with psychotic experiences while adjusting for important sociodemographic characteristics and familial factors and investigating the effect of age. The South East London Community Health (SELCoH) study is a population-based household survey of physical and mental health in individuals 16 years or older conducted from June 1, 2008, to December 31, 2010, in 2 London boroughs. The study included 1698 participants from 1075 households. Data were analyzed from May 6, 2014, to April 22, 2015. Psychotic experiences measured using the Psychosis Screening Questionnaire. Neuropsychological functioning measured using tests assessing verbal knowledge (Wechsler Test of Adult Reading), working memory (Spatial Delayed Response Task), memory (Visual Object Learning Task), and processing speed (digit symbol coding task). A composite IQ score of general cognitive ability was calculated. A total of 1677 participants with a mean (SD) age of 40 (17) years were included in the analysis. Compared with the group without psychotic experiences, the 171 (9.7%) adults with psychotic experiences did not show a statistically significant impairment on mean (SD) measures of IQ (95.25 [16.58] vs 100.45 [14.77]; Cohen d, -0.22; P = .06) or processing speed (40.63 [13.06] vs 42.17 [13.79]; Cohen d, -0.03; P = .73) but were impaired on measures of verbal knowledge (31.36 [15.78] vs 38.83 [12.64]; Cohen d, -0.37; P = .003), working memory (20.97 [4.12] vs 22.51 [3.26]; Cohen d, -0.34; P = .005), and memory (43.80 [8.45] vs 46.53 [7.06]; Cohen d, -0.28; P = .01). Only participants 50 years and older with psychotic

  5. Transgender Population Size in the United States: a Meta-Regression of Population-Based Probability Samples.

    Science.gov (United States)

    Meerwijk, Esther L; Sevelius, Jae M

    2017-02-01

    Transgender individuals have a gender identity that differs from the sex they were assigned at birth. The population size of transgender individuals in the United States is not well-known, in part because official records, including the US Census, do not include data on gender identity. Population surveys today more often collect transgender-inclusive gender-identity data, and secular trends in culture and the media have created a somewhat more favorable environment for transgender people. To estimate the current population size of transgender individuals in the United States and evaluate any trend over time. In June and July 2016, we searched PubMed, Cumulative Index to Nursing and Allied Health Literature, and Web of Science for national surveys, as well as "gray" literature, through an Internet search. We limited the search to 2006 through 2016. We selected population-based surveys that used probability sampling and included self-reported transgender-identity data. We used random-effects meta-analysis to pool eligible surveys and used meta-regression to address our hypothesis that the transgender population size estimate would increase over time. We used subsample and leave-one-out analysis to assess for bias. Our meta-regression model, based on 12 surveys covering 2007 to 2015, explained 62.5% of model heterogeneity, with a significant effect for each unit increase in survey year (F = 17.122; df = 1,10; b = 0.026%; P = .002). Extrapolating these results to 2016 suggested a current US population size of 390 adults per 100 000, or almost 1 million adults nationally. This estimate may be more indicative for younger adults, who represented more than 50% of the respondents in our analysis. Future national surveys are likely to observe higher numbers of transgender people. The large variety in questions used to ask about transgender identity may account for residual heterogeneity in our models. Public health implications. Under- or nonrepresentation

  6. Transgender Population Size in the United States: a Meta-Regression of Population-Based Probability Samples

    Science.gov (United States)

    Sevelius, Jae M.

    2017-01-01

    Background. Transgender individuals have a gender identity that differs from the sex they were assigned at birth. The population size of transgender individuals in the United States is not well-known, in part because official records, including the US Census, do not include data on gender identity. Population surveys today more often collect transgender-inclusive gender-identity data, and secular trends in culture and the media have created a somewhat more favorable environment for transgender people. Objectives. To estimate the current population size of transgender individuals in the United States and evaluate any trend over time. Search methods. In June and July 2016, we searched PubMed, Cumulative Index to Nursing and Allied Health Literature, and Web of Science for national surveys, as well as “gray” literature, through an Internet search. We limited the search to 2006 through 2016. Selection criteria. We selected population-based surveys that used probability sampling and included self-reported transgender-identity data. Data collection and analysis. We used random-effects meta-analysis to pool eligible surveys and used meta-regression to address our hypothesis that the transgender population size estimate would increase over time. We used subsample and leave-one-out analysis to assess for bias. Main results. Our meta-regression model, based on 12 surveys covering 2007 to 2015, explained 62.5% of model heterogeneity, with a significant effect for each unit increase in survey year (F = 17.122; df = 1,10; b = 0.026%; P = .002). Extrapolating these results to 2016 suggested a current US population size of 390 adults per 100 000, or almost 1 million adults nationally. This estimate may be more indicative for younger adults, who represented more than 50% of the respondents in our analysis. Authors’ conclusions. Future national surveys are likely to observe higher numbers of transgender people. The large variety in questions used to ask

  7. Eating patterns in a population-based sample of children aged 5 to 7 years

    DEFF Research Database (Denmark)

    Micali, Nadia; Simonoff, Emily; Elberling, Hanne

    2011-01-01

    There is still a lack of research on childhood eating patterns and their correlates in relation to psychopathology and parentally perceived impact in general population samples. We aimed to determine which eating patterns were more likely to be identified as problematic by parents, and their impa...... and association with childhood psychopathology (emotional, behavioral, and pervasive developmental disorders) in a general population child cohort....

  8. Self-Harmful Behaviors in a Population-Based Sample of Young Adults

    Science.gov (United States)

    Nada-Raja, Shyamala; Skegg, Keren; Langley, John; Morrison, Dianne; Sowerby, Paula

    2004-01-01

    A birth cohort of 472 women and 494 men aged 26 years was interviewed about a range of self-harmful behaviors first and then asked about suicidal intent.- Lifetime prevalence of self-harm using traditional methods of suicide (ICD [International Classification of Diseases] self-harm) was 13%, with 9% of the sample describing at least one such…

  9. Eating patterns in a population-based sample of children aged 5 to 7 years

    DEFF Research Database (Denmark)

    Micali, Nadia; Simonoff, Emily; Elberling, Hanne

    2011-01-01

    There is still a lack of research on childhood eating patterns and their correlates in relation to psychopathology and parentally perceived impact in general population samples. We aimed to determine which eating patterns were more likely to be identified as problematic by parents, and their impact...... and association with childhood psychopathology (emotional, behavioral, and pervasive developmental disorders) in a general population child cohort....

  10. Assessment of TREM2 rs75932628 association with Alzheimer's disease in a population-based sample: the Cache County Study.

    Science.gov (United States)

    Gonzalez Murcia, Josue D; Schmutz, Cameron; Munger, Caitlin; Perkes, Ammon; Gustin, Aaron; Peterson, Michael; Ebbert, Mark T W; Norton, Maria C; Tschanz, Joann T; Munger, Ronald G; Corcoran, Christopher D; Kauwe, John S K

    2013-12-01

    Recent studies have identified the rs75932628 (R47H) variant in TREM2 as an Alzheimer's disease risk factor with estimated odds ratio ranging from 2.9 to 5.1. The Cache County Memory Study is a large, population-based sample designed for the study of memory and aging. We genotyped R47H in 2974 samples (427 cases and 2540 control subjects) from the Cache County study using a custom TaqMan assay. We observed 7 heterozygous cases and 12 heterozygous control subjects with an odds ratio of 3.5 (95% confidence interval, 1.3-8.8; p = 0.0076). The minor allele frequency and population attributable fraction for R47H were 0.0029 and 0.004, respectively. This study replicates the association between R47H and Alzheimer's disease risk in a large, population-based sample, and estimates the population frequency and attributable risk of this rare variant. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. The association between Internet addiction and personality disorders in a general population-based sample.

    Science.gov (United States)

    Zadra, Sina; Bischof, Gallus; Besser, Bettina; Bischof, Anja; Meyer, Christian; John, Ulrich; Rumpf, Hans-Jürgen

    2016-12-01

    Background and aims Data on Internet addiction (IA) and its association with personality disorder are rare. Previous studies are largely restricted to clinical samples and insufficient measurement of IA. Methods Cross-sectional analysis data are based on a German sub-sample (n = 168; 86 males; 71 meeting criteria for IA) with increased levels of excessive Internet use derived from a general population sample (n = 15,023). IA was assessed with a comprehensive standardized interview using the structure of the Composite International Diagnostic Interview and the criteria of Internet Gaming Disorder as suggested in DSM-5. Impulsivity, attention deficit hyperactivity disorder, and self-esteem were assessed with the widely used questionnaires. Results Participants with IA showed higher frequencies of personality disorders (29.6%) compared to those without IA (9.3%; p Cluster C personality disorders were more prevalent than among non-addicted males. Compared to participants who had IA only, lower rates of remission of IA were found among participants with IA and additional cluster B personality disorder. Personality disorders were significantly associated with IA in multivariate analysis. Comorbidity of IA and personality disorders must be considered in prevention and treatment.

  12. Measurement Invariance of the WHODAS 2.0 in a Population-Based Sample of Youth.

    Directory of Open Access Journals (Sweden)

    Melissa Kimber

    Full Text Available The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0 is a brief measure of global disability originally developed for adults, which has since been implemented among samples of children and youth. However, evidence of its validity for use among youth, particularly measurement invariance, is lacking. Investigations of measurement invariance assess the extent to which the psychometric properties of observed items in a measure are generalizable across samples. Satisfying the assumption of measurement invariance is critical for any inferences about between-group differences. The objective of this paper was to empirically assess the measurement invariance of the 12-item interview version of the WHODAS 2.0 measure in an epidemiological sample of youth (15 to 17 years and adults (≥ 18 years in Canada. Multiple-group confirmatory factor analysis using a categorical variable framework allowed for the sequential testing of increasingly restrictive models to evaluate measurement invariance of the WHODAS 2.0 between adults and youth. Findings provided evidence for full measurement invariance of the WHODAS 2.0 in youth aged 15 to 17 years. The final model fit the data well: χ(2(159 = 769.04, p < .001; CFI = 0.950, TLI = 0.958, RMSEA (90% CI = 0.055 [0.051, 0.059]. Results from this study build on previous work supporting the validity of the WHODAS 2.0. Findings indicate that the WHODAS 2.0 is valid for making substantive comparisons of disability among youth as young as 15 years of age.

  13. Predicting the urge to smoke in a population-based sample of adolescent smokers.

    Science.gov (United States)

    Tagmat, Deniz; Wolff, Judith; Ruege, Jeannette; John, Ulrich; Thyrian, Jochen René

    2010-08-01

    Little is known about the relationship between smoking urges and situations in adolescence, although adolescent smoking is specifically bound to characteristics, such as peer group situations. Therefore, we performed ordinal regression analyses to predict this situational urge to smoke by smoking-related variables. A sample of N = 1,093 adolescents in North-Eastern Germany was used in 2005/2006. High parameter values on all predictors had the highest odds for situational urge followed by moderate and low parameter values. Implications/limitations are described.

  14. Variation in distress among women with infertility: evidence from a population-based sample

    DEFF Research Database (Denmark)

    Greil, Arthur L; Shreffler, Karina M; Schmidt, Lone

    2011-01-01

    for Epidemiological Studies-Depression. Multiple regression analysis was conducted on self-report data (based on a telephone interview) from a probability-based sample of US women aged 25-45 years. We compare women with infertility who have had a prior pregnancy (secondary infertility, n = 628) to women...... with infertility with no prior pregnancies (primary infertility, n = 399). We further distinguish between women with infertility who were actually 'trying' to become pregnant (the infertile with intent) with those who met the medical definition of infertile but did not describe themselves as trying to become...

  15. Cardiovascular disease risk factors in a population-based sample of Norwegian children and adolescents

    DEFF Research Database (Denmark)

    Steene-Johannessen, Jostein; Kolle, Elin; Anderssen, Sigmund Alfred

    2009-01-01

    -olds from all regions of the country was sampled. Of 2,818 subjects invited to participate, 2,299 accepted, giving an overall participation rate of 82 %. Results. Mean (SD) values for the main risk factors for 9-year-old and 15-year-old girls and boys were: total cholesterol (TC) (mmol/L) 4.49 (0.73), 4...... as expected. A significant degree of clustering of CVD risk factors was found in 11.4 % (95 % CI, 9.8 to 13.0) of the study population, and these had mean Z scores of 1.24 (0.06) and 1.04 (0.08) for the 9-year-olds and 15-year-olds, respectively. Conclusion. This study presents national reference data...

  16. Association between socioeconomic factors and sleep quality in an urban population-based sample in Germany

    DEFF Research Database (Denmark)

    Anders, Markus P; Breckenkamp, Jürgen; Blettner, Maria

    2014-01-01

    this association, taking particularly the effect of health confounders into consideration. METHODS: The data were extracted from the cross-sectional QUEBEB Study. In total, the study sample consisted of 3281 participants (1817 women and 1464 men, aged 16-72 years). Here socioeconomic status (SES) was collected...... from the baseline survey taken in 2004. Sleep quality for the same participants was measured with in-depth personal interviews in 2006 using the Pittsburgh Sleep Quality Index, together with other relevant characteristics (e.g. anxiety, depression and health status). Multiple logistic regression......, but also health status, are also associated with sleep quality and can influence in part the socioeconomic levels seen in sleep quality. CONCLUSION: SES and sleep quality are associated. However, there are important additional determinants that influence the level of association between SES and sleep...

  17. Headache complaints associated with psychiatric comorbidity in a population-based sample

    Directory of Open Access Journals (Sweden)

    Benseñor I.M.

    2003-01-01

    Full Text Available The objective of the present study was to determine the frequency at which people complain of any type of headache, and its relationship with sociodemographic characteristics and psychiatric comorbidity in São Paulo, Brazil. A three-step cluster sampling method was used to select 1,464 subjects aged 18 years or older. They were mainly from families of middle and upper socioeconomic levels living in the catchment area of Instituto de Psiquiatria. However, this area also contains some slums and shantytowns. The subjects were interviewed using the Brazilian version of the Composite International Diagnostic Interview version 1.1. (CIDI 1.1 by a lay trained interviewer. Answers to CIDI 1.1 questions allowed us to classify people according to their psychiatric condition and their headaches based on their own ideas about the nature of their illness. The lifetime prevalence of "a lot of problems with" headache was 37.4% (76.2% of which were attributed to use of medicines, drugs/alcohol, physical illness or trauma, and 23.8% attributed to nervousness, tension or mental illness. The odds ratio (OR for headache among participants with "nervousness, tension or mental illness" was elevated for depressive episodes (OR, 2.1; 95%CI, 1.4-3.4, dysthymia (OR, 3.4; 95%CI, 1.6-7.4 and generalized anxiety disorder (OR, 4.3; 95%CI, 2.1-8.6, when compared with patients without headache. For "a lot of problems with" headaches attributed to medicines, drugs/alcohol, physical illness or trauma, the risk was also increased for dysthymia but not for generalized anxiety disorder. These data show a high association between headache and chronic psychiatric disorders in this Brazilian population sample.

  18. Headache complaints associated with psychiatric comorbidity in a population-based sample.

    Science.gov (United States)

    Benseñor, I M; Tófoli, L F; Andrade, L

    2003-10-01

    The objective of the present study was to determine the frequency at which people complain of any type of headache, and its relationship with sociodemographic characteristics and psychiatric comorbidity in S o Paulo, Brazil. A three-step cluster sampling method was used to select 1,464 subjects aged 18 years or older. They were mainly from families of middle and upper socioeconomic levels living in the catchment area of Instituto de Psiquiatria. However, this area also contains some slums and shantytowns. The subjects were interviewed using the Brazilian version of the Composite International Diagnostic Interview version 1.1. (CIDI 1.1) by a lay trained interviewer. Answers to CIDI 1.1 questions allowed us to classify people according to their psychiatric condition and their headaches based on their own ideas about the nature of their illness. The lifetime prevalence of "a lot of problems with" headache was 37.4% (76.2% of which were attributed to use of medicines, drugs/alcohol, physical illness or trauma, and 23.8% attributed to nervousness, tension or mental illness). The odds ratio (OR) for headache among participants with "nervousness, tension or mental illness" was elevated for depressive episodes (OR, 2.1; 95%CI, 1.4-3.4), dysthymia (OR, 3.4; 95%CI, 1.6-7.4) and generalized anxiety disorder (OR, 4.3; 95%CI, 2.1-8.6), when compared with patients without headache. For "a lot of problems with" headaches attributed to medicines, drugs/alcohol, physical illness or trauma, the risk was also increased for dysthymia but not for generalized anxiety disorder. These data show a high association between headache and chronic psychiatric disorders in this Brazilian population sample.

  19. Perceptions of care coordination in a population-based sample of diverse breast cancer patients.

    Science.gov (United States)

    Hawley, Sarah T; Janz, Nancy K; Lillie, Sarah E; Friese, Christopher R; Griggs, Jennifer J; Graff, John J; Hamilton, Ann S; Jain, Sarika; Katz, Steven J

    2010-12-01

    To identify factors associated with perceptions of care coordination in a diverse sample of breast cancer patients. Breast cancer patients reported to the metropolitan SEER registries of Detroit or Los Angeles from 6/05 to 2/07 were surveyed after diagnosis (N=2268, RR=72.4%). Outcomes were two dichotomous measures reflecting patient appraisal of care coordination during their treatment experience. Primary independent variables were race/ethnicity (white, African American, Latina-high acculturated, Latina-low acculturated) and health literacy (low, moderate, high). Logistic regression was used to evaluate factors associated with both measures of care coordination. 2148 subjects were included in the analytic dataset. 16.4% of women perceived low care coordination and 12.5% reported low satisfaction. Race/ethnicity was not significantly associated with care coordination. Women with low subjective health literacy were 3-4 times as likely as those with high health literacy to perceive low care coordination and low satisfaction with care coordination (OR=3.88; 95% CI: 2.78-5.41; OR=3.19 95% CI: 2.25-4.52, respectively). Many breast cancer patients positively appraised their care coordination, but patients with low health literacy perceived low care coordination. Providers should be aware of the health literacy deficits that may contribute to their patients' attitudes towards their breast cancer care coordination. Published by Elsevier Ireland Ltd.

  20. Sports and energy drink consumption among a population-based sample of young adults

    Science.gov (United States)

    Larson, Nicole; Laska, Melissa N.; Story, Mary; Neumark-Sztainer, Dianne

    2017-01-01

    Objective National data for the U.S. show increases in sports and energy drink consumption over the past decade with the largest increases among young adults ages 20–34. This study aimed to identify sociodemographic factors and health risk behaviors associated with sports and energy drink consumption among young adults. Design Cross-sectional analysis of survey data from the third wave of a cohort study (Project EAT-III: Eating and Activity in Teens and Young Adults). Regression models stratified on gender and adjusted for sociodemographic characteristics were used to examine associations of sports and energy drink consumption with eating behaviors, physical activity, media use, weight-control behaviors, sleep patterns, and substance use. Setting Participants completed baseline surveys in 1998–1999 as students at public secondary schools in Minneapolis/St. Paul, Minnesota and the EAT-III surveys online or by mail in 2008–2009. Subjects The sample consisted of 2,287 participants (55% female, mean age=25.3). Results Results showed 31.0% of young adults consumed sports drinks and 18.8% consumed energy drinks at least weekly. Among men and women, sports drink consumption was associated with higher sugar-sweetened soda and fruit juice intake, video game use, and use of muscle-enhancing substances like creatine (pdrink consumption was associated with lower breakfast frequency and higher sugar-sweetened soda intake, video game use, use of unhealthy weight-control behaviors, trouble sleeping, and substance use among men and women (psports and energy drink consumption with other unhealthy behaviors in the design of programs and services for young adults. PMID:25683863

  1. Factors distinguishing youth who report self-injurious behavior: a population-based sample.

    Science.gov (United States)

    Taliaferro, Lindsay A; Muehlenkamp, Jennifer J; Borowsky, Iris W; McMorris, Barbara J; Kugler, Kari C

    2012-01-01

    To identify factors distinguishing adolescents across 3 groups: no self-harm, nonsuicidal self-injury (NSSI) only, and NSSI and suicide attempt (NSSI + SA). Data were from the 2007 Minnesota Student Survey. The sample included 61,330 students in grades 9 and 12. Logistic regression analysis determined factors that best distinguished adolescents who reported NSSI from those who reported no self-harm, and adolescents who reported NSSI + SA. Final models were developed over 3 stages of analysis that tested the importance of variables within risk factor, protective factor, and co-occurring health-risk behavior domains. For male and female subjects, factors that consistently distinguished youth who reported NSSI from those who reported no self-harm included depressive symptoms, hopelessness, physical abuse, less parent connectedness, running away from home, and maladaptive dieting behavior. Factors that distinguished the NSSI + SA group from the NSSI only group for both sexes were a mental health problem, depressive symptoms, hopelessness, physical abuse, and running away from home. Other factors, such as sexual abuse, were significant in models for males or females only. Hopelessness constituted the leading factor to increase the likelihood that youth who self-injured also attempted suicide. Youth engaging in NSSI experience diverse psychosocial stressors and significant distress. Clinicians and school personnel are well-positioned to offer support to these youth. Furthermore, they can help address NSSI among youth by identifying those who self-injure early, assessing for hopelessness and suicidality, facilitating connections to prosocial adults, addressing maladaptive dieting behavior, and supporting runaway youth. Copyright © 2012 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

  2. Subfertility Increases Risk of Testicular Cancer: Evidence from Population-Based Semen Samples

    Science.gov (United States)

    Hanson, Heidi A; Anderson, Ross E; Aston, Kenneth I; Carrell, Douglas T; Smith, Ken R; Hotaling, James M

    2015-01-01

    Objective To further understand the association between semen quality and cancer risk using well-defined semen parameters. Design Retrospective cohort study. Setting Subfertility Heath and Assisted Reproduction (SHARE) study in Utah from 1994 to 2011. Patients 20,433 men from that underwent semen analysis (SA) and a sample of 20,433 fertile controls matched on age and birth year Interventions none. Main Outcome Measures Risk of all cancers, as well as site-specific results for prostate, testicular, and melanoma. Results Relative to fertile men, men with SA have an increased risk of testicular cancer (Hazard Rate Ratio (HR) =3.3). When the characterization of infertility is refined using individual semen parameters, we find that oligozoospermic men have an increased risk of cancer relative to fertile controls. This association is particularly strong for testicular cancer, with increased risk in men with oligozoospermia based on concentration (HR=11.9) and sperm count (HR=10.3). Men in the in the lowest quartile of motility (HR=4.1), viability (HR=6.6), morphology (HR=4.2) or total motile count (HR=6.9) have higher risk of testicular compared to fertile men. Men with sperm concentration and count in the 90th percentile of the distribution (≥178 M/ml and ≥579, respectively) and total motile count (TMC) have an increased risk of melanoma (HRConcentration=2.1; HRCount=2.7; HRTMC=2.0). We find no differences in cancer risk between azoospermic and fertile men. Conclusions Men with SA have an increased risk of testicular cancer that varies by semen quality. Unlike prior work, we did not find an association between azoospermia and increased cancer or testicular cancer risk. Capsule Subfertile men have an increased risk of testicular cancer that varies by semen quality. We did not find an association between azoospermia and increased cancer or testicular cancer risk. PMID:26604070

  3. Executive Cognitive Functioning and Cardiovascular Autonomic Regulation in a Population-Based sample of Working Adults

    Directory of Open Access Journals (Sweden)

    Cecilia Ulrika Dagsdotter Stenfors

    2016-10-01

    Full Text Available Objective: Executive cognitive functioning is essential in private and working life and is sensitive to stress and aging. Cardiovascular (CV health factors are related to cognitive decline and dementia, but there is relatively few studies of the role of CV autonomic regulation, a key component in stress responses and risk factor for cardiovascular disease (CVD, and executive processes. An emerging pattern of results from previous studies suggest that different executive processes may be differentially associated with CV autonomic regulationThe aim was thus to study the associations between multiple measures of CV autonomic regulation and measures of different executive cognitive processes. Method: Participants were 119 healthy working adults (79% women, from the Swedish Longitudinal Occupational Survey of Health. Electrocardiogram was sampled for analysis of heart rate variability measures, including the Standard Deviation of NN, here heart beats (SDNN, root of the mean squares of successive differences (RMSSD, high frequency (HF power band from spectral analyses, and QT variability index (QTVI, a measure of myocardial repolarization patterns. Executive cognitive functioning was measured by 7 neuropsychological tests. The relationships between CV autonomic regulation measures and executive cognitive measures were tested with bivariate and partial correlational analyses, controlling for demographic variables and mental health symptoms.Results: Higher SDNN and RMSSD and lower QTVI were significantly associated with better performance on cognitive tests tapping inhibition, updating, shifting and psychomotor speed. After adjustments for demographic factors however (age being the greatest confounder, only QTVI was clearly associated with these executive tests. No such associations were seen for working memory capacity. Conclusion: Poorer cardiovascular autonomic regulation in terms of lower SDNN & RMSSD and higher QTVI was associated with poorer

  4. Executive Cognitive Functioning and Cardiovascular Autonomic Regulation in a Population-Based Sample of Working Adults.

    Science.gov (United States)

    Stenfors, Cecilia U D; Hanson, Linda M; Theorell, Töres; Osika, Walter S

    2016-01-01

    Objective: Executive cognitive functioning is essential in private and working life and is sensitive to stress and aging. Cardiovascular (CV) health factors are related to cognitive decline and dementia, but there is relatively few studies of the role of CV autonomic regulation, a key component in stress responses and risk factor for cardiovascular disease (CVD), and executive processes. An emerging pattern of results from previous studies suggest that different executive processes may be differentially associated with CV autonomic regulation. The aim was thus to study the associations between multiple measures of CV autonomic regulation and measures of different executive cognitive processes. Method: Participants were 119 healthy working adults (79% women), from the Swedish Longitudinal Occupational Survey of Health. Electrocardiogram was sampled for analysis of heart rate variability (HRV) measures, including the Standard Deviation of NN, here heart beats (SDNN), root of the mean squares of successive differences (RMSSD), high frequency (HF) power band from spectral analyses, and QT variability index (QTVI), a measure of myocardial repolarization patterns. Executive cognitive functioning was measured by seven neuropsychological tests. The relationships between CV autonomic regulation measures and executive cognitive measures were tested with bivariate and partial correlational analyses, controlling for demographic variables, and mental health symptoms. Results: Higher SDNN and RMSSD and lower QTVI were significantly associated with better performance on cognitive tests tapping inhibition, updating, shifting, and psychomotor speed. After adjustments for demographic factors however (age being the greatest confounder), only QTVI was clearly associated with these executive tests. No such associations were seen for working memory capacity. Conclusion: Poorer CV autonomic regulation in terms of lower SDNN and RMSSD and higher QTVI was associated with poorer executive

  5. Feasibility of Gamified Mobile Service Aimed at Physical Activation in Young Men: Population-Based Randomized Controlled Study (MOPO).

    Science.gov (United States)

    Leinonen, Anna-Maiju; Pyky, Riitta; Ahola, Riikka; Kangas, Maarit; Siirtola, Pekka; Luoto, Tim; Enwald, Heidi; Ikäheimo, Tiina M; Röning, Juha; Keinänen-Kiukaanniemi, Sirkka; Mäntysaari, Matti; Korpelainen, Raija; Jämsä, Timo

    2017-10-10

    The majority of young people do not meet the recommendations on physical activity for health. New innovative ways to motivate young people to adopt a physically active lifestyle are needed. The study aimed to study the feasibility of an automated, gamified, tailored Web-based mobile service aimed at physical and social activation among young men. A population-based sample of 496 young men (mean age 17.8 years [standard deviation 0.6]) participated in a 6-month randomized controlled trial (MOPO study). Participants were randomized to an intervention (n=250) and a control group (n=246). The intervention group was given a wrist-worn physical activity monitor (Polar Active) with physical activity feedback and access to a gamified Web-based mobile service, providing fitness guidelines, tailored health information, advice of youth services, social networking, and feedback on physical activity. Through the trial, the physical activity of the men in the control group was measured continuously with an otherwise similar monitor but providing only the time of day and no feedback. The primary outcome was the feasibility of the service based on log data and questionnaires. Among completers, we also analyzed the change in anthropometry and fitness between baseline and 6 months and the change over time in weekly time spent in moderate to vigorous physical activity. Mobile service users considered the various functionalities related to physical activity important. However, compliance of the service was limited, with 161 (64.4%, 161/250) participants visiting the service, 118 (47.2%, 118/250) logging in more than once, and 41 (16.4%, 41/250) more than 5 times. Baseline sedentary time was higher in those who uploaded physical activity data until the end of the trial (P=.02). A total of 187 (74.8%, 187/250) participants in the intervention and 167 (67.9%, 167/246) in the control group participated in the final measurements. There were no differences in the change in anthropometry and

  6. Cervical cancer incidence after normal cytological sample in routine screening using SurePath, ThinPrep, and conventional cytology: population based study

    NARCIS (Netherlands)

    K. Rozemeijer (Kirsten); S.K. Naber (Steffie); C. Penning (Corine); L.I.H. Overbeek (Lucy); C.W.N. Looman (Caspar); I.M.C.M. de Kok (Inge); S.M. Matthijsse (Suzette); M. Rebolj (Matejka); F.J. van Kemenade (Folkert); M. van Ballegooijen (Marjolein)

    2017-01-01

    markdownabstract#### Objective To compare the cumulative incidence of cervical cancer diagnosed within 72 months after a normal screening sample between conventional cytology and liquid based cytology tests SurePath and ThinPrep. #### Design Retrospective population based cohort

  7. A simple method to generate equal-sized homogenous strata or clusters for population-based sampling.

    Science.gov (United States)

    Elliott, Michael R

    2011-04-01

    Statistical efficiency and cost efficiency can be achieved in population-based samples through stratification and/or clustering. Strata typically combine subgroups of the population that are similar with respect to an outcome. Clusters are often taken from preexisting units, but may be formed to minimize between-cluster variance, or to equalize exposure to a treatment or risk factor. Area probability sample design procedures for the National Children's Study required contiguous strata and clusters that maximized within-stratum and within-cluster homogeneity while maintaining approximately equal size of the strata or clusters. However, there were few methods that allowed such strata or clusters to be constructed under these contiguity and equal size constraints. A search algorithm generates equal-size cluster sets that approximately span the space of all possible clusters of equal size. An optimal cluster set is chosen based on analysis of variance and convexity criteria. The proposed algorithm is used to construct 10 strata based on demographics and air pollution measures in Kent County, MI, following census tract boundaries. A brief simulation study is also conducted. The proposed algorithm is effective at uncovering underlying clusters from noisy data. It can be used in multi-stage sampling where equal-size strata or clusters are desired. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Comparison of sample characteristics in two pregnancy cohorts: community-based versus population-based recruitment methods.

    Science.gov (United States)

    Leung, Brenda My; McDonald, Sheila W; Kaplan, Bonnie J; Giesbrecht, Gerald F; Tough, Suzanne C

    2013-12-06

    One of the biggest challenges for population health studies is the recruitment of participants. Questions that investigators have asked are "who volunteers for studies?" and "does recruitment method influence characteristics of the samples?" The purpose of this paper was to compare sample characteristics of two unrelated pregnancy cohort studies taking place in the same city, in the same time period, that employed different recruitment strategies, as well as to compare the characteristics of both cohorts to provincial and national statistics derived from the Maternity Experiences Survey (MES). One pregnancy cohort used community-based recruitment (e.g. posters, pamphlets, interviews with community media and face-to-face recruitment in maternity clinics); the second pregnancy cohort used both community-based and population-based (a centralized system identifying pregnant women undergoing routine laboratory testing) strategies. The pregnancy cohorts differed in education, income, ethnicity, and foreign-born status (p recruitment of participants will not necessarily result in samples that reflect the general population, but can reflect the target population of interest. Attracting and retaining young, low resource women into urban studies about pregnancy may require alternate and innovative approaches.

  9. Prevalence of age-related macular degeneration in a population-based sample of Hispanic people in Arizona: Proyecto VER.

    Science.gov (United States)

    Muñoz, Beatriz; Klein, Ronald; Rodriguez, Jorge; Snyder, Robert; West, Sheila K

    2005-11-01

    To report the prevalence of age-related macular degeneration (AMD) in a population-based sample of Hispanic individuals aged 50 years and older. Proyecto VER (Vision and Eye Research) is a population-based study of blindness and visual impairment of Hispanic people in Arizona. Participants underwent complete ophthalmic evaluation, including stereoscopic fundus photography of fields 1, 2, and 4. All photographs for participants aged 50 years and older were graded using the Wisconsin Age-Related Maculopathy Grading system. The following signs were graded: drusen size, drusen type, and the area covered by drusen; pigmentary abnormalities; geographic atrophy; and exudative AMD. Sixty-seven percent (3178) of the original 4774 participants were 50 years of age or older. Of those, 92% (2928) had fundus photographs in at least 1 eye, and 95% (2780) of the photographs were of sufficient quality to grade early and late AMD. The overall prevalence of late AMD was 0.5%. The prevalence increased from 0.1% in the 50- to 59-year age group to 4.3% in the group aged 80 years and older. Likewise, early AMD was strongly associated with age with a prevalence of 20% in the 50- to 59-year age group, increasing to 54% in the group aged 80 years and older. The prevalence of early AMD in Hispanic people was significantly higher than the reported prevalence in the white population. However, the prevalence of late AMD was lower than the estimates for the white population of the United States. Although early macular changes were very common among Hispanic people, the prevalence of late AMD was infrequent. Further work is necessary to understand the underlying reasons for the different patterns of presentation of early and late signs of AMD among racial/ethnic groups and to characterize early AMD based on predictive value for severe disease in different populations.

  10. The impact of obesity and weight gain on development of sleep problems in a population-based sample.

    Science.gov (United States)

    Palm, Andreas; Janson, Christer; Lindberg, Eva

    2015-05-01

    The objective of this study was to investigate the role of obesity and weight gain in the development of sleep problems in a population-based cohort. A population-based sample of men (n = 1896, aged 40-79 years) and women (n = 5116, age ≥20 years) responded to questionnaires at baseline and follow-up after 10-13 years. Sleep problems were assessed through questions about difficulties initiating sleep (DIS), difficulties maintaining sleep (DMS), excessive daytime sleepiness (EDS), and insomnia. Body mass index (BMI) was calculated from self-reported weight and height at both baseline and follow-up, while confounding factors (physical activity, tobacco and alcohol use, somatic disease, and snoring) were based on responses at baseline. Although overweight and obese subjects reported more sleep problems at baseline, there was no independent association between BMI level at baseline and development of new sleep problems. Subjects in the quartile with the highest rise in BMI with a weight gain exceeding 2.06 kg/m2 had a higher risk of developing DMS [adjusted odds ratio (OR) 1.58; 95% confidence interval (CI) 1.25-2.01), EDS (2.25; 1.65-3.06], and insomnia (2.78; 1.60-4.82). Weight gain was not associated with the development of DIS. Weight gain is an independent risk factor for developing several sleep problems and daytime sleepiness. The presence of overweight and weight gain should be considered when treating patients with sleep problems. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Seroprevalence of Borrelia burgdorferi, Anaplasma phagocytophilum, and Francisella tularensis Infections in Belgium: Results of Three Population-Based Samples.

    Science.gov (United States)

    De Keukeleire, Mathilde; Vanwambeke, Sophie O; Cochez, Christel; Heyman, Paul; Fretin, David; Deneys, Véronique; Luyasu, Victor; Kabamba, Benoît; Robert, Annie

    2017-02-01

    To estimate the seroprevalence of Borrelia burgdorferi (Bb), Anaplasma phagocytophilum (Ap), and Francisella tularensis (Ft) in Belgium, we tested sera from three population-based samples in which exposure to pathogen is assumed to vary: 148 samples from workers professionally exposed, 209 samples from rural blood donors, and 193 samples from urban blood donors. Sera were tested using ELISA or the immunofluorescence assay test. The seroprevalence of Bb was 5.4% in workers professionally exposed, 2.9% in rural blood donors, and 2.6% in urban blood donors, which is similar to other studies. The fraction of negative results decreases significantly from urban blood donors and rural blood donors to workers. Regarding the seroprevalence of Ap, the cutoff titer of 1:64 recommended by the manufacturer may be set too low and produces artificially high seroprevalence rates. Using a cutoff titer of 1:128, the seroprevalence of Ap was estimated at 8.1% for workers professionally exposed, 6.2% for rural blood donors, and 5.7% for urban blood donors. Tularemia sera confirmed the presence of the pathogen in Belgium at 2.0% for workers and 0.5% for rural and urban blood donors. Our study is one of the few providing an estimation of the seroprevalences of Bb, Ap, and Ft in three different populations in Belgium, filling the gap in seroprevalence data among those groups. Our findings provide evidence that the entire Belgian population is exposed to Bb, Ap, and Ft infections, but a higher exposure is noticed for professionals at risk. Education on the risk factors for tick bites and preventive measures for both professionals exposed and the general population is needed.

  12. Preservation of the Semantic Verbal Fluency Advantage in a Large Population-Based Sample: Normative Data from the TILDA Study.

    Science.gov (United States)

    Vaughan, Roisin M; Coen, Robert F; Kenny, RoseAnne; Lawlor, Brian A

    2016-05-01

    It is widely believed that phonemic fluency is more difficult than naming exemplars from a semantic category. Normative data in this regard are scarce, and there is considerable disagreement in the literature regarding the pattern in normal ageing and neurodegenerative conditions. Our objective was to provide normative data for semantic phonemic discrepancy scores from a large sample of older adults. A total of 5780 community-dwelling older adults were included in this prospective, longitudinal study. Discrepancy scores were calculated by subtracting phonemic fluency score from semantic fluency score for each participant. Quantile regression was used to estimate normative values stratified for age. Subjects did better on testing of semantic fluency. The average discrepancy score was 9.18±6.89 words, (range, -20 to 37; n=5780). At the fiftieth percentile, those in their fifth decade produced 10 more "animals" than "letter F" words. Subjects scored one word less per decade, with an average of seven more "animal" words produced by those in their eighth decade. Our study is the first to provide normative data and confirms that, for animal versus letter F fluency, the semantic advantage persists into later life in a population-based sample of community-dwelling older adults. Given that a majority of clinical samples have confirmed a reverse of this pattern in Alzheimer's dementia (i.e., loss of semantic advantage in Alzheimer's disease, yielding a phonemic advantage), our findings support the clinical utility of brief fluency tests and encourage further research into their use in diagnosis and prediction of progression to dementia.

  13. Loneliness and the metabolic syndrome in a population-based sample of middle-aged and older adults.

    Science.gov (United States)

    Whisman, Mark A

    2010-09-01

    This study evaluated the association between loneliness and the metabolic syndrome, which refers to a clustering of factors that have been shown to increase risk for cardiovascular disease, diabetes, stroke, and mortality. A secondary purpose was to evaluate whether age moderated the association between loneliness and the metabolic syndrome. Participants were 52 to 79 years old, and they were drawn from a population-based survey of people 50 years of age and older living in England (N = 3211). They completed a self-report measure of loneliness and a nurse visit that included collection of blood pressure, blood sample, and anthropometric measures. Self-reported loneliness and the metabolic syndrome. After controlling for demographic variables and smoking status, loneliness was significantly associated with increasing likelihood of meeting criteria for the metabolic syndrome and with the individual criterion of central obesity. The association between loneliness and the metabolic syndrome was not moderated by age. Results suggest that loneliness is associated with the metabolic syndrome. Therefore, the metabolic syndrome may be among the pathways by which loneliness increases risk of morbidity and mortality. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  14. Replication of the association between CHRNA4 rs1044396 and harm avoidance in a large population-based sample.

    Science.gov (United States)

    Bey, Katharina; Lennertz, Leonhard; Markett, Sebastian; Petrovsky, Nadine; Gallinat, Jürgen; Gründer, Gerhard; Spreckelmeyer, Katja N; Wienker, Thomas F; Mobascher, Arian; Dahmen, Norbert; Thuerauf, Norbert; Kornhuber, Johannes; Kiefer, Falk; Toliat, Mohammad R; Nürnberg, Peter; Winterer, Georg; Wagner, Michael

    2016-01-01

    Harm avoidance is a personality trait characterized by excessive worrying and fear of uncertainty, which has repeatedly been related to anxiety disorders. Converging lines of research in rodents and humans point towards an involvement of the nicotinic cholinergic system in the modulation of anxiety. Most notably, the rs1044396 polymorphism in the CHRNA4 gene, which codes for the α4 subunit of the nicotinic acetylcholine receptor, has been linked to negative emotionality traits including harm avoidance in a recent study. Against this background, we investigated the association between harm avoidance and the rs1044396 polymorphism using data from N=1673 healthy subjects, which were collected in the context of the German multi-centre study ׳Genetics of Nicotine Dependence and Neurobiological Phenotypes׳. Homozygous carriers of the C-allele showed significantly higher levels of harm avoidance than homozygous T-allele carriers, with heterozygous subjects exhibiting intermediate scores. The effect was neither modulated by age or gender nor by smoking status. By replicating previous findings in a large population-based sample for the first time, the present study adds to the growing evidence suggesting an involvement of nicotinic cholinergic mechanism in anxiety and negative emotionality, which may pose an effective target for medical treatment. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.

  15. Hand Function in a Population-Based Sample of Young Children with Unilateral or Bilateral Cerebral Palsy.

    Science.gov (United States)

    Klevberg, Gunvor L; Østensjø, Sigrid; Krumlinde-Sundholm, Lena; Elkjær, Sonja; Jahnsen, Reidun B

    2017-10-20

    To describe aspects of hand function in a population-based sample of young children with clinical signs of unilateral or bilateral cerebral palsy (CP). A cross-sectional study with data from national CP registers in Norway. Manual ability was classified with the Manual Ability Classification System (MACS) or Mini-MACS. Hand use in bimanual activities was measured with the Assisting Hand Assessment (AHA) for unilateral CP or the newly developed Both Hands Assessment (BoHA) for bilateral CP. From 202 children, 128 (57 females) were included (Mini-MACS/MACS levels I-V, mean age 30.4 months; SD = 12.1). Manual abilities were distributed across levels I-III in unilateral CP and levels I-V in bilateral CP. Variations in AHA and BoHA units were large. One-way ANOVA revealed associations between higher AHA or BoHA units and Mini-MACS/MACS levels of higher ability (p CP, children with bilateral CP showed greater variation in Mini-MACS/MACS levels, and both sub-groups showed large variations in AHA or BoHA units. The classifications and assessments used in this study are useful to differentiate young children's ability levels. Such information is important to tailor upper limb interventions to the specific needs of children with CP.

  16. Sources of Variation on the Mini-Mental State Examination in a Population-Based Sample of Centenarians

    Science.gov (United States)

    Dai, Ting; Davey, Adam; Woodard, John L.; Miller, L. Stephen; Gondo, Yasuyuki; Kim, Seock-Ho; Poon, Leonard W.

    2013-01-01

    Centenarians represent a rare but rapidly growing segment of the oldest-old. This study presents item-level data from the Mini-Mental State Examination (MMSE, M=16.2, SD=8.8, Range 0–30) in a cross-sectional, population-based sample of 244 centenarians and near-centenarians (aged 98–108, 16% men, 21% African-American, 38% community-dwelling) from the Georgia Centenarian Study (2001–2008) by age, education, sex, race, and residential status. Multiple-Indicator Multiple-Causes (MIMIC) models were used to identify systematic domain-level differences on MMSE scores by key demographic characteristics in this age group. Indirect effects of age, educational attainment, race, and residential status were found on MMSE scores. Direct effects were limited to concentration for education and race, and orientation for residential status. Mean levels of cognitive functioning in centenarians were low, with mean values below most commonly-used cut-offs. Overall scores on the MMSE differed as a function of age, education, race, and residential status, with differences in scale performance limited primarily to concentration and orientation, with no evidence for interactions among centenarian characteristics. Adjusting for education was not sufficient to account for differences by race; adjusting for residential status was not sufficient to account for differences by age. PMID:23889552

  17. Psychometric properties of the Social Phobia and Anxiety Inventory for Children using a non-American population-based sample.

    Science.gov (United States)

    Aune, Tore; Stiles, Tore C; Svarva, Kyrre

    2008-08-01

    Although previous studies have examined the factor structure of the SPAI-C, adequate factor analytic methodology has not been employed. This study explored the psychometric properties of the Social Phobia and Anxiety Inventory for Children (SPAI-C), using a non-American population-based sample of older children and young adolescents 11-14 years of age. Initially an exploratory factor analysis was conducted followed 1 year later by a confirmatory factor analysis. Five factors labeled Assertiveness, Public Performance, Physical/Cognitive Symptoms, Social Encounter, and Avoidance were retained and confirmed. The Public Performance and Assertiveness factors were the most stable and consistent factors or traits of social anxiety over a 1-year period. Results revealed adequate concurrent validity, internal consistency and moderate 12-month test-retest reliability of the SPAI-C total scale. The SPAI-C was found to assess levels of both social anxiety and social anxiety disorder according to DSM-IV criteria. Findings suggest that the SPAI-C is applicable in clinical treatment studies designed to assess sensitivity to change in various aspects of social anxiety disorder.

  18. Adverse childhood experiences in relation to mood and anxiety disorders in a population-based sample of active military personnel.

    Science.gov (United States)

    Sareen, J; Henriksen, C A; Bolton, S L; Afifi, T O; Stein, M B; Asmundson, G J G

    2013-01-01

    Although it has been posited that exposure to adverse childhood experiences (ACEs) increases vulnerability to deployment stress, previous literature in this area has demonstrated conflicting results. Using a cross-sectional population-based sample of active military personnel, the present study examined the relationship between ACEs, deployment related stressors and mood and anxiety disorders. Data were analyzed from the 2002 Canadian Community Health Survey-Canadian Forces Supplement (CCHS-CFS; n = 8340, age 18-54 years, response rate 81%). The following ACEs were self-reported retrospectively: childhood physical abuse, childhood sexual abuse, economic deprivation, exposure to domestic violence, parental divorce/separation, parental substance abuse problems, hospitalization as a child, and apprehension by a child protection service. DSM-IV mood and anxiety disorders [major depressive disorder, post-traumatic stress disorder (PTSD), generalized anxiety disorder (GAD), panic attacks/disorder and social phobia] were assessed using the composite international diagnostic interview (CIDI). Even after adjusting for the effects of deployment-related traumatic exposures (DRTEs), exposure to ACEs was significantly associated with past-year mood or anxiety disorder among men [adjusted odds ratio (aOR) 1.34, 99% confidence interval (CI) 1.03-1.73, p military personnel. Intervention strategies to prevent mental health problems should consider the utility of targeting soldiers with exposure to ACEs.

  19. Homogeneous Combinations of ASD-ADHD Traits and Their Cognitive and Behavioral Correlates in a Population-Based Sample.

    Science.gov (United States)

    van der Meer, Jolanda M J; Lappenschaar, Martijn G A; Hartman, Catharina A; Greven, Corina U; Buitelaar, Jan K; Rommelse, Nanda N J

    2017-07-01

    Autism Spectrum Disorders (ASD) and ADHD are assumed to be the extreme manifestations of continuous heterogeneous traits that frequently co-occur. This study aims to identify subgroups of children with distinct ASD-ADHD trait profiles in the general population, using measures sensitive across both trait continua, and show how these subgroups differ in cognitive functioning. We examined 378 children (6-13 years) from a population-based sample. Latent class analyses (LCA) detected three concordant classes with low (10.1%), medium (54.2%), or high (13.2%) scores on both traits, and two discordant classes with more ADHD than ASD characteristics (ADHD > ASD, 18.3%) and vice versa (ASD > ADHD, 4.2%). Findings suggest that ASD and ADHD traits usually are strongly related in the unaffected population, and that a minority of children displays atypical discordant trait profiles characterized by differential visual-spatial functioning. This dissociation suggests that heterogeneity in ASD and ADHD is rooted in heterogeneity in the lower unaffected end of the distribution.

  20. Physical exercise and burnout facets predict injuries in a population-based sample of French career firefighters.

    Science.gov (United States)

    Vaulerin, Jérôme; d'Arripe-Longueville, Fabienne; Emile, Mélanie; Colson, Serge S

    2016-05-01

    Although firefighting is known to engender a high rate of injury, few studies have examined the contribution of physical exercise, burnout and coping strategies to firefighting-related injuries. Data were collected from a population-based sample of 220 male firefighters. In a descriptive study, the nature and site of the injuries and the relationships among firefighter injuries, physical exercise, burnout and coping strategies were examined. Sprains were the most prevalent type of injury (98%), followed by tendinitis (40%) and muscle tears (30%). More than two thirds of these injuries were located at the ankle. Weekly hours of physical exercise, cognitive weariness at work, social support seeking, problem-focused coping and emotional exhaustion were significantly related to these injuries. The findings suggest that physical exercise and cognitive weariness can be considered as risk factors for French firefighter injuries, whereas problem-focused coping can be seen as a protective factor. More research is needed to explain the relationship between social support seeking and injury. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  1. Social phobia in a population-based female adolescent twin sample: co-morbidity and associated suicide-related symptoms.

    Science.gov (United States)

    Nelson, E C; Grant, J D; Bucholz, K K; Glowinski, A; Madden PAF; Reich, W; Heath, A C

    2000-07-01

    This report attempted to replicate and extend prior work examining social phobia (SP), co-morbid psychiatric illnesses, and the risk of suicidal ideation and suicide attempts incurred by their adolescent sufferers. SP, alcohol dependence (ALD) and major depressive disorder (MDD) diagnoses, and suicide-related symptoms, were assessed in a population-based adolescent female twin sample. The differentiation of risks as a function of co-morbidity was explored. A trivariate model was fitted to estimate sharing of genetic and environmental vulnerability between SP and co-morbid disorders. The lifetime prevalence of SP was 16.3 %. Significant risk for co-morbid MDD (OR = 3.2) and ALD (OR = 2.1) was observed. Strong evidence for shared genetic vulnerability between SP and MDD (respective heritabilities 28%, 45%; genetic r = 1.0) was observed with moderate support noted for similar sharing between SP and ALD (genetic r = 0.52, heritability for ALD 63%). SP with co-morbid MDD was associated with elevated risk for ALD and for suicide-related symptoms. SP is a common illness often followed by co-morbid MDD and ALD. SP with comorbid MDD predicts a substantially elevated risk of ALD and suicide-related symptoms, stressing the need for early SP detection.

  2. Prevalence, genotyping, and correlates of anogenital HPV infection in a population-based sample of women in Puerto Rico

    Directory of Open Access Journals (Sweden)

    A.P. Ortiz

    2016-12-01

    Full Text Available Background: Oncogenic HPV infection is associated to anogenital cancer. We estimate the prevalence and correlates of anogenital HPV infection among a population-based sample of women aged 16–64 years living in the metropolitan area of Puerto Rico. Methods: 564 women completed face-to-face and computer assisted interviews and self-collected anal and cervical specimens. HPV DNA testing used MY09/MY11 consensus HPV L1 primers and beta-globin as an internal control for sample amplification. Positive specimens were typed by dot-blot hybridization. Results: Weighted prevalence of cervical, anal, and cervical/anal co-infection was 29.4%, 38.6%, and 17.1%, respectively. The commonest oncogenic HPV types detected in the cervix and anus were: 68 (8% vs. 7% and 16 (5.5% vs. 5.1%, correspondingly. Having ≥3 lifetime sexual partners (OR: 2.3; 95% CI: 1.5–3.5 and last year anal intercourse (OR: 1.6; 95% CI: 1.1–2.5 increased the odds of anogenital HPV infection. Cervical infection was independently associated to anal infection (OR: 3.0; 95% CI: 2.0–4.6. Conclusions: Similar to others, our results confirm the burden of anogenital HPV infection in women and its relationship with sexual behavior. As vaccination increases, future studies should monitor changing trends in HPV infection in this population, and the relationship between anal and cervical HPV-related disease. Keywords: Anogenital HPV infection, Women, Hispanics, Puerto Rico

  3. k-Means: Random Sampling Procedure

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. k-Means: Random Sampling Procedure. Optimal 1-Mean is. Approximation of Centroid (Inaba et al). S = random sample of size O(1/ ); Centroid of S is a (1+ )-approx centroid of P with constant probability.

  4. The AMEL study, a cross sectional population-based survey on aging and malnutrition in 1200 elderly Lebanese living in rural settings: protocol and sample characteristics

    Science.gov (United States)

    2013-01-01

    Background Lebanon is faced with a particular challenge because of large socioeconomic inequality and accelerated demographic transition. Rural residents seem more vulnerable because of limited access to transport, health and social services. No information is available regarding health, nutrition and living conditions of this specific population. The purpose of the AMEL (Aging and Malnutrition in Elderly Lebanese) study is to assess the nutritional status of community dwelling elderly people, aged 65 years and above, living in a rural settings in Lebanon, in line of socioeconomic factors, health and living conditions. The present paper will describe the gender specific characteristics of the study population. Methods AMEL is a cross-sectional population based study conducted between April 2011 and April 2012 including 1200 elderly individuals living in the 24 rural Caza (districts) of Lebanon. People aged greater than or equal to 65 y were randomly selected through multistage cluster sampling. Subjects were interviewed at their homes by trained interviewers. The questionnaire included the following measures: socio-demographic factors, nutritional status (Mini Nutritional Assessment, MNA), health related characteristics, functional ability, cognitive status, mood and social network. Results The sample included 591 men (49.3%) and 609 women (50.8%). Mean age was 75.32 years and similar between genders. Malnutrition (MNA community dwelling rural residents of Lebanon. These findings may alert policy makers to plan appropriate intervention in order to improve the quality of life and increase successful aging. PMID:23758758

  5. Health and human rights in Chin State, Western Burma: a population-based assessment using multistaged household cluster sampling.

    Directory of Open Access Journals (Sweden)

    Richard Sollom

    Full Text Available BACKGROUND: The Chin State of Burma (also known as Myanmar is an isolated ethnic minority area with poor health outcomes and reports of food insecurity and human rights violations. We report on a population-based assessment of health and human rights in Chin State. We sought to quantify reported human rights violations in Chin State and associations between these reported violations and health status at the household level. METHODS AND FINDINGS: Multistaged household cluster sampling was done. Heads of household were interviewed on demographics, access to health care, health status, food insecurity, forced displacement, forced labor, and other human rights violations during the preceding 12 months. Ratios of the prevalence of household hunger comparing exposed and unexposed to each reported violation were estimated using binomial regression, and 95% confidence intervals (CIs were constructed. Multivariate models were done to adjust for possible confounders. Overall, 91.9% of households (95% CI 89.7%-94.1% reported forced labor in the past 12 months. Forty-three percent of households met FANTA-2 (Food and Nutrition Technical Assistance II project definitions for moderate to severe household hunger. Common violations reported were food theft, livestock theft or killing, forced displacement, beatings and torture, detentions, disappearances, and religious and ethnic persecution. Self reporting of multiple rights abuses was independently associated with household hunger. CONCLUSIONS: Our findings indicate widespread self-reports of human rights violations. The nature and extent of these violations may warrant investigation by the United Nations or International Criminal Court. Please see later in the article for the Editors' Summary.

  6. Health and Human Rights in Chin State, Western Burma: A Population-Based Assessment Using Multistaged Household Cluster Sampling

    Science.gov (United States)

    Sollom, Richard; Richards, Adam K.; Parmar, Parveen; Mullany, Luke C.; Lian, Salai Bawi; Iacopino, Vincent; Beyrer, Chris

    2011-01-01

    Background The Chin State of Burma (also known as Myanmar) is an isolated ethnic minority area with poor health outcomes and reports of food insecurity and human rights violations. We report on a population-based assessment of health and human rights in Chin State. We sought to quantify reported human rights violations in Chin State and associations between these reported violations and health status at the household level. Methods and Findings Multistaged household cluster sampling was done. Heads of household were interviewed on demographics, access to health care, health status, food insecurity, forced displacement, forced labor, and other human rights violations during the preceding 12 months. Ratios of the prevalence of household hunger comparing exposed and unexposed to each reported violation were estimated using binomial regression, and 95% confidence intervals (CIs) were constructed. Multivariate models were done to adjust for possible confounders. Overall, 91.9% of households (95% CI 89.7%–94.1%) reported forced labor in the past 12 months. Forty-three percent of households met FANTA-2 (Food and Nutrition Technical Assistance II project) definitions for moderate to severe household hunger. Common violations reported were food theft, livestock theft or killing, forced displacement, beatings and torture, detentions, disappearances, and religious and ethnic persecution. Self reporting of multiple rights abuses was independently associated with household hunger. Conclusions Our findings indicate widespread self-reports of human rights violations. The nature and extent of these violations may warrant investigation by the United Nations or International Criminal Court. Please see later in the article for the Editors' Summary PMID:21346799

  7. Depression, obesity, and metabolic syndrome: prevalence and risks of comorbidity in a population-based representative sample of Mexican Americans.

    Science.gov (United States)

    Olvera, Rene L; Williamson, Douglas E; Fisher-Hoch, Susan P; Vatcheva, Kristina P; McCormick, Joseph B

    2015-10-01

    We examined the prevalence of depression, obesity, and metabolic syndrome and associations between them in a population-based representative cohort of Mexican Americans living on the United States-Mexico border. The sample in this cross-sectional analysis consisted of 1,768 Mexican American adults (≥ 18 years of age) assessed between the years 2004 and 2010, with whom we tested our central hypothesis of a significant relationship between obesity and depression. Depression was measured using the Center for Epidemiologic Studies-Depression scale (CES-D) with a cutoff score of ≥ 16 for depression and a cutoff score of ≥ 27 for severe depression. We categorized body mass index (BMI) values as obese (≥ 30kg/m(2)) and later subdivided the obese subjects into obese (30-39 kg/m(2)[inclusive]) and morbidly obese (≥ 40 kg/m(2)). Metabolic syndrome was defined using the American Heart Association definition requiring at least 3 of the following: increased waist circumference, elevated triglycerides, reduced high-density lipoprotein (HDL) cholesterol, elevated blood pressure, and elevated fasting glucose. Weighted data were analyzed to establish prevalence of depression, obesity, and metabolic syndrome. Univariate and multivariable weighted regression models were used to test potential associations between these disorders. Using weighted prevalence, we observed high rates of depression (30%), obesity (52%), and metabolic syndrome (45%). Univariate models revealed female gender (P = .0004), low education (P = .003), low HDL level (P = .009), and increased waist circumference (P = .03) were associated with depression. Female gender (P = .01), low education (P = .003), and morbid obesity (P = .002) were risk factors for severe depression and remained significant in multivariable models. In this large cohort of Mexican Americans, obesity, female gender, and low education were identified risk factors for depression. These indicators may serve as targets for early

  8. Racial disparities in BRCA testing and cancer risk management across a population-based sample of young breast cancer survivors.

    Science.gov (United States)

    Cragun, Deborah; Weidner, Anne; Lewis, Courtney; Bonner, Devon; Kim, Jongphil; Vadaparampil, Susan T; Pal, Tuya

    2017-07-01

    Breast cancer (BC) disparities may widen with genomic advances. The authors compared non-Hispanic white (NHW), black, and Hispanic BC survivors for 1) cancer risk-management practices among BRCA carriers and 2) provider discussion and receipt of genetic testing. A population-based sample of NHW, black, and Hispanic women who had been diagnosed with invasive BC at age 50 years or younger from 2009 to 2012 were recruited through the state cancer registry. Multiple logistic regression was used to compare cancer risk-management practices in BRCA carriers and associations of demographic and clinical variables with provider discussion and receipt of testing. Of 1622 participants, 159 of 440 (36.1%) black women, 579 of 897 (64.5%) NHW women, 58 of 117 (49.6%) Spanish-speaking Hispanic women, and 116 of 168 (69%) English-speaking Hispanic women underwent BRCA testing, of whom 90 had a pathogenic BRCA mutation identified. Among BRCA carriers, the rates of risk-reducing mastectomy and risk-reducing salpingo-oophorectomy were significantly lower among black women compared with Hispanic and NHW women after controlling for clinical and demographic variables (P = .025 and P = .008, respectively). Compared with NHW women, discussion of genetic testing with a provider was 16 times less likely among black women (P testing arise from cancer risk-management practice options. Furthermore, lower BRCA testing rates among blacks may partially be because of a lower likelihood of provider discussion. Future studies are needed to improve cancer risk identification and management practices across all populations to prevent the widening of disparities. Cancer 2017;123:2497-05. © 2017 American Cancer Society. © 2017 American Cancer Society.

  9. Defining "Normophilic" and "Paraphilic" Sexual Fantasies in a Population-Based Sample: On the Importance of Considering Subgroups.

    Science.gov (United States)

    Joyal, Christian C

    2015-12-01

    interests, and the crucial difference between SF and sexual interest is underlined. Joyal CC. Defining "normophilic" and "paraphilic" sexual fantasies in a population-based sample: On the importance of considering subgroups. Sex Med 2015;3:321-330.

  10. A two-stage cluster sampling method using gridded population data, a GIS, and Google EarthTM imagery in a population-based mortality survey in Iraq

    Directory of Open Access Journals (Sweden)

    Galway LP

    2012-04-01

    Full Text Available Abstract Background Mortality estimates can measure and monitor the impacts of conflict on a population, guide humanitarian efforts, and help to better understand the public health impacts of conflict. Vital statistics registration and surveillance systems are rarely functional in conflict settings, posing a challenge of estimating mortality using retrospective population-based surveys. Results We present a two-stage cluster sampling method for application in population-based mortality surveys. The sampling method utilizes gridded population data and a geographic information system (GIS to select clusters in the first sampling stage and Google Earth TM imagery and sampling grids to select households in the second sampling stage. The sampling method is implemented in a household mortality study in Iraq in 2011. Factors affecting feasibility and methodological quality are described. Conclusion Sampling is a challenge in retrospective population-based mortality studies and alternatives that improve on the conventional approaches are needed. The sampling strategy presented here was designed to generate a representative sample of the Iraqi population while reducing the potential for bias and considering the context specific challenges of the study setting. This sampling strategy, or variations on it, are adaptable and should be considered and tested in other conflict settings.

  11. Longitudinal assessment of injury recidivism among adults in the United States: findings from a population-based sample.

    Science.gov (United States)

    Alghnam, Suliman; Tinkoff, Glen H; Castillo, Renan

    2016-12-01

    Repeated injuries, as known as injury recidivism, pose a significant burden on population health and healthcare settings. Therefore, identifying those at risk of recidivism can highlight targeted populations for primary prevention in order to improve health and reduce healthcare expenditures. There has been limited research on factors associated with recidivism in the U.S. Using a population-based sample, we aim to: 1) identify the prevalence and risk factors for injury recidivism among non-institutionalized adults; 2) investigate the trend in nationwide recidivism rates over time. Using the Medical Expenditure Panel Survey (MEPS), 19,134 adults with at least one reported injury were followed for about 2 years. Reported injuries were those associated with healthcare utilization, disability days or any effects on self-reported health. The independent associations between risk factors for recidivism were evaluated incorporating a weighted logistic regression model. There were 4,136 recidivists representing over nine million individuals in the U.S. over a 2-year follow-up. About 44 % of recidivists sustained severe injuries requiring a hospitalization, a physician's office visit or an emergency department visit. Compared with those who sustained a single injury, recidivists were more likely to be white, unmarried, reside in metropolitan areas, and report a higher prevalence of chronic conditions. Age, sex, race/ethnicity, marital status, urbanicity, region, diabetes, stroke, asthma and depression symptoms were significant predictors of recidivism. Significant interaction effects between age and gender suggested those in the 18-25 age group, the odds of being a recidivist were 1.45 higher among males than females adjusting for other covariates. While having positive screens for depression in both follow-up years was associated with 1.46 (95 % CI = 1.21-1.77) higher odds of recidivisms than the reference group adjusting for other variables. We observed a higher

  12. Impact of prevalent and incident vertebral fractures on utility: results from a patient-based and a population-based sample

    NARCIS (Netherlands)

    Schoor, van N.; Ewing, S.; O’Neill, T.; Lunt, M.; Smit, J.; Lips, P.

    2007-01-01

    Data are scarce on the impact of vertebral fractures (VFX) on utility. The objective of this study was to assess the impact of prevalent and incident VFX on utility in both a patient-based and population-based sample. Data from the Multiple Outcomes of Raloxifene Evaluation (MORE) study (n = 550

  13. Association studies of novel obesity-related gene variants with quantitative metabolic phenotypes in a population-based sample of 6,039 Danish individuals

    DEFF Research Database (Denmark)

    Burgdorf, K S; Gjesing, A P; Grarup, N

    2011-01-01

    in an epidemiological setting. METHODS: By applying an additive genetic model, 14 WHR-associated gene variants and 18 BMI-associated variants were investigated for their relationships with glucose-related metabolic traits in treatment-naive individuals from the population-based Inter99 study sample (n¿=¿6,039). RESULTS...

  14. Cervical cancer incidence after normal cytological sample in routine screening using SurePath, ThinPrep, and conventional cytology: population based study

    NARCIS (Netherlands)

    Rozemeijer, K.; Naber, S.K.; Penning, C.; Overbeek, L.I.H.; Looman, C.W.; Kok, I.M. de; Matthijsse, S.M.; Rebolj, M.; Kemenade, F.J. van; Ballegooijen, M. van

    2017-01-01

    Objective To compare the cumulative incidence of cervical cancer diagnosed within 72 months after a normal screening sample between conventional cytology and liquid based cytology tests SurePath and ThinPrep.Design Retrospective population based cohort study.Setting Nationwide network and registry

  15. Assessing the Validity of a Stage Measure on Physical Activity in a Population-Based Sample of Individuals with Type 1 or Type 2 Diabetes

    Science.gov (United States)

    Plotnikoff, Ronald C.; Lippke, Sonia; Reinbold-Matthews, Melissa; Courneya, Kerry S.; Karunamuni, Nandini; Sigal, Ronald J.; Birkett, Nicholas

    2007-01-01

    This study was designed to test the validity of a transtheoretical model's physical activity (PA) stage measure with intention and different intensities of behavior in a large population-based sample of adults living with diabetes (Type 1 diabetes, n = 697; Type 2 diabetes, n = 1,614) and examine different age groups. The overall…

  16. Living conditions, including life style, in primary-care patients with nonacute, nonspecific spinal pain compared with a population-based sample: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Odd Lindell

    2010-11-01

    Full Text Available Odd Lindell, Sven-Erik Johansson, Lars-Erik Strender1Center for Family and Community Medicine, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, SwedenBackground: Nonspecific spinal pain (NSP, comprising back and/or neck pain, is one of the leading disorders behind long-term sick-listing, including disability pensions. Early interventions to prevent long-term sick-listing require the identification of patients at risk. The aim of this study was to compare living conditions associated with long-term sick-listing for NSP in patients with nonacute NSP, with a nonpatient population-based sample. Nonacute NSP is pain that leads to full-time sick-listing>3 weeks.Methods: One hundred and twenty-five patients with nonacute NSP, 2000–2004, were included in a randomized controlled trial in Stockholm County with the objective of comparing cognitive–behavioral rehabilitation with traditional primary care. For these patients, a cross-sectional study was carried out with baseline data. Living conditions were compared between the patients and 338 nonpatients by logistic regression. The conditions from univariate analyses were included in a multivariate analysis. The nonsignificant variables were excluded sequentially to yield a model comprising only the significant factors (P <0.05. The results are shown as odds ratios (OR with 95% confidence intervals.Results: In the univariate analyses, 13 of the 18 living conditions had higher odds for the patients with a dominance of physical work strains and Indication of alcohol over-consumption, odds ratio (OR 14.8 (95% confidence interval [CI] 3.2–67.6. Five conditions qualified for the multivariate model: High physical workload, OR 13.7 (CI 5.9–32.2; Hectic work tempo, OR 8.4 (CI 2.5–28.3; Blue-collar job, OR 4.5 (CI 1.8–11.4; Obesity, OR 3.5 (CI 1.2–10.2; and Low education, OR 2.7 (CI 1.1–6.8.Conclusions: As most of the living conditions have previously been

  17. Association between plasma leptin and blood pressure in two population-based samples of children and adolescents

    DEFF Research Database (Denmark)

    Grøntved, Anders; Steene-Johannessen, Jostein; Kynde, Iben

    2011-01-01

    In this study we examined the association between leptin and blood pressure in a population-based study of Danish and Norwegian children and adolescents. Because of the putative bidirectional relationship between leptin and adiposity we formally tested (i) the mediating effect of body mass index...... in the association between leptin and blood pressure, and (ii) the mediating effect of leptin in the association between body mass index and blood pressure....

  18. Screening for Ataxia-Telangiectasia Mutations in a Population-Based Sample of Women with Early-Onset Breast Cancer

    Science.gov (United States)

    1999-09-01

    G, Itnyre J (1997) Prevalence and contribution of BRCA1 mutations in breast and ovarian cancer: results from three U.S. population-based case-control...GTTAAGAA two of these cases, AT1ILA and AT119LA, the families were consanguineous , and the mutations were homo- zygous, simplifying the interpretation...screening efficiency and expand significantly the number of cases to be screened. Assessment of the prevalence of ATM mutations in breast cancer

  19. Contralateral Prophylactic Mastectomy Decisions in a Population-Based Sample of Patients With Early-Stage Breast Cancer.

    Science.gov (United States)

    Jagsi, Reshma; Hawley, Sarah T; Griffith, Kent A; Janz, Nancy K; Kurian, Allison W; Ward, Kevin C; Hamilton, Ann S; Morrow, Monica; Katz, Steven J

    2017-03-01

    Contralateral prophylactic mastectomy (CPM) use is increasing among women with unilateral breast cancer, but little is known about treatment decision making or physician interactions in diverse patient populations. To evaluate patient motivations, knowledge, and decisions, as well as the impact of surgeon recommendations, in a large, diverse sample of patients who underwent recent treatment for breast cancer. A survey was sent to 3631 women with newly diagnosed, unilateral stage 0, I, or II breast cancer between July 2013 and September 2014. Women were identified through the population-based Surveillance Epidemiology and End Results registries of Los Angeles County and Georgia. Data on surgical decisions, motivations for those decisions, and knowledge were included in the analysis. Logistic and multinomial logistic regression of the data were conducted to identify factors associated with (1) CPM vs all other treatments combined, (2) CPM vs unilateral mastectomy (UM), and (3) CPM vs breast-conserving surgery (BCS). Associations between CPM receipt and surgeon recommendations were also evaluated. All statistical models and summary estimates were weighted to be representative of the target population. Receipt of CPM was the primary dependent variable for analysis and was measured by a woman's self-report of her treatment. Of the 3631 women selected to receive the survey, 2578 (71.0%) responded and 2402 of these respondents who did not have bilateral disease and for whom surgery type was known constituted the final analytic sample. The mean (SD) age was 61.8 (12) years at the time of the survey. Overall, 1301 (43.9%) patients considered CPM (601 [24.8%] considered it very strongly or strongly); only 395 (38.1%) of them knew that CPM does not improve survival for all women with breast cancer. Ultimately, 1466 women (61.6%) received BCS, 508 (21.2%) underwent UM, and 428 (17.3%) received CPM. On multivariable analysis, factors associated with CPM included younger age

  20. K-Median: Random Sampling Procedure

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. K-Median: Random Sampling Procedure. Sample a set of 1/ + 1 points from P. Let Q = first 1/ points, p = last point. Let T = Avg. 1-Median cost of P, c=1-Median. Let B1 = B(c,T/ 2), B2 = B(p, T). Let P' = points in B1.

  1. Access and completion of a Web-based treatment in a population-based sample of tornado-affected adolescents.

    Science.gov (United States)

    Price, Matthew; Yuen, Erica K; Davidson, Tatiana M; Hubel, Grace; Ruggiero, Kenneth J

    2015-08-01

    Although Web-based treatments have significant potential to assess and treat difficult-to-reach populations, such as trauma-exposed adolescents, the extent that such treatments are accessed and used is unclear. The present study evaluated the proportion of adolescents who accessed and completed a Web-based treatment for postdisaster mental health symptoms. Correlates of access and completion were examined. A sample of 2,000 adolescents living in tornado-affected communities was assessed via structured telephone interview and invited to a Web-based treatment. The modular treatment addressed symptoms of posttraumatic stress disorder, depression, and alcohol and tobacco use. Participants were randomized to experimental or control conditions after accessing the site. Overall access for the intervention was 35.8%. Module completion for those who accessed ranged from 52.8% to 85.6%. Adolescents with parents who used the Internet to obtain health-related information were more likely to access the treatment. Adolescent males were less likely to access the treatment. Future work is needed to identify strategies to further increase the reach of Web-based treatments to provide clinical services in a postdisaster context. (c) 2015 APA, all rights reserved).

  2. Importance and determinants of Gleason score undergrading on biopsy sample of prostate cancer in a population-based study.

    Science.gov (United States)

    Rapiti, Elisabetta; Schaffar, Robin; Iselin, Christophe; Miralbell, Raymond; Pelte, Marie-Françoise; Weber, Damien; Zanetti, Roberto; Neyroud-Caspar, Isabelle; Bouchardy, Christine

    2013-04-11

    In this population-based study, we investigated the degree of concordance between Gleason scores obtained from prostate biopsies and those obtained from prostatectomy specimens, as well as the determinants of biopsy understaging. We considered for this study all 371 prostate cancer patients recorded at the Geneva Cancer Registry diagnosed from 2004 to 2006 who underwent a radical prostatectomy. We used the kappa statistic to evaluate the Gleason score concordance from biopsy and prostatectomy specimens. Logistic regression was used to determine the parameters that predict the undergrading of the Gleason score in prostate biopsies. The kappa statistic between biopsy and prostatectomy Gleason score was 0.42 (p Gleason score underestimated by the biopsy. In a multi-adjusted model, increasing age, advanced clinical stage, having less than ten biopsy cores, and longer delay between the two procedures, were all independently associated with biopsy undergrading. In particular, the proportion of exact match increased to 72% when the patients had ten or more needle biopsy cores. The main limitation of the study is that both biopsy and prostatectomy specimens were examined by different laboratories. The data show that concordance between biopsy and prostatectomy Gleason scores lies within the classic clinical standards in this population-based study. The number of biopsy cores appears to strongly impact on the concordance between biopsy and radical prostatectomy Gleason score.

  3. Association of Common Polymorphisms in the Nicotinic Acetylcholine Receptor Alpha4 Subunit Gene with an Electrophysiological Endophenotype in a Large Population-Based Sample.

    Directory of Open Access Journals (Sweden)

    A Mobascher

    Full Text Available Variation in genes coding for nicotinic acetylcholine receptor (nAChR subunits affect cognitive processes and may contribute to the genetic architecture of neuropsychiatric disorders. Single nucleotide polymorphisms (SNPs in the CHRNA4 gene that codes for the alpha4 subunit of alpha4/beta2-containing receptors have previously been implicated in aspects of (mostly visual attention and smoking-related behavioral measures. Here we investigated the effects of six synonymous but functional CHRNA4 exon 5 SNPs on the N100 event-related potential (ERP, an electrophysiological endophenotype elicited by a standard auditory oddball. A total of N = 1,705 subjects randomly selected from the general population were studied with electroencephalography (EEG as part of the German Multicenter Study on nicotine addiction. Two of the six variants, rs1044396 and neighboring rs1044397, were significantly associated with N100 amplitude. This effect was pronounced in females where we also observed an effect on reaction time. Sequencing of the complete exon 5 region in the population sample excluded the existence of additional/functional variants that may be responsible for the observed effects. This is the first large-scale population-based study investigation the effects of CHRNA4 SNPs on brain activity measures related to stimulus processing and attention. Our results provide further evidence that common synonymous CHRNA4 exon 5 SNPs affect cognitive processes and suggest that they also play a role in the auditory system. As N100 amplitude reduction is considered a schizophrenia-related endophenotype the SNPs studied here may also be associated with schizophrenia outcome measures.

  4. Geographical distribution, socioeconomic status and health- related physical fitness in adolescents from a large population-based sample from Bogotá, Colombia: the ser study

    OpenAIRE

    Rodrigues-Bezerra, Diogo

    2016-01-01

    Background: The negative gradient between socio-economic status and prevalence of non-communicable disease in adulthood has prompted investigation of potential foundations based in childhood. The objective of the present study is to examine the influence of socio-geographical variations and socioeconomic status on health-related physical fitness in adolescents from a large population-based sample of Colombian ninth graders. Methods: During the 2014–2015 school years, we examined a cross-secti...

  5. Psychopathological mechanisms linking childhood traumatic experiences to risk of psychotic symptoms: analysis of a large, representative population-based sample.

    Science.gov (United States)

    van Nierop, Martine; Lataster, Tineke; Smeets, Feikje; Gunther, Nicole; van Zelst, Catherine; de Graaf, Ron; ten Have, Margreet; van Dorsselaer, Saskia; Bak, Maarten; Myin-Germeys, Inez; Viechtbauer, Wolfgang; van Os, Jim; van Winkel, Ruud

    2014-03-01

    Different psychological models of trauma-induced psychosis have been postulated, often based on the observation of "specific" associations between particular types of childhood trauma (CT) and particular psychotic symptoms or the co-occurrence of delusions and hallucinations. However, the actual specificity of these associations remains to be tested. In 2 population-based studies with comparable methodology (Netherlands Mental Health Survey and Incidence Study-1 [NEMESIS-1] and NEMESIS-2, N = 13 722), trained interviewers assessed CT, psychotic symptoms, and other psychopathology. Specificity of associations was assessed with mixed-effects regression models with multiple outcomes, a statistical method suitable to examine specificity of associations in case of multiple correlated outcomes. Associations with CT were strong and significant across the entire range of psychotic symptoms, without evidence for specificity in the relationship between particular trauma variables and particular psychotic experiences (PEs). Abuse and neglect were both associated with PEs (OR abuse: 2.12, P effect size. Intention-to-harm experiences showed stronger associations with psychosis than CT without intent (χ(2) = 58.62, P traumatic experiences to psychosis, most likely characterized by co-occurrence of hallucinations and delusions, indicating buildup of psychotic intensification, rather than specific psychotic symptoms in isolation. No evidence was found to support psychological theories regarding specific associations between particular types of CT and particular psychotic symptoms.

  6. Association of physical activity intensity levels with overweight and obesity in a population-based sample of adults.

    Science.gov (United States)

    Bernstein, Martine S; Costanza, Michael C; Morabia, Alfredo

    2004-01-01

    Clarify the association between physical activity intensity and overweight/obesity. Population-based 1997-2001 survey in Geneva, Switzerland (n=5,757, ages 35 to 74). Intensity of physical activity energy expenditure (EE) defined as percentage of total EE in moderate activities [3-3.9 x basal metabolism rate (BMR), e.g., normal walking, household chores] and high-intensity activities (> or =4 x BMR, e.g., brisk walking, sports). Overweight or obesity based on measured body mass index (BMI). Comparing participants in the lowest vs. the highest tertile of the percentage of high-intensity EE, the odds ratios (ORs) were, for obesity vs. normal weight, 2.8 (95% confidence interval: 2.0-3.8, Pmoderate-intensity EE. This cross-sectional study cannot determine whether exercise is an effective strategy for weight control or whether overweight or obese people exercise less. However, clear dose-response associations in both genders between obesity or overweight and energy expenditure in high (but not in moderate)-intensity activities are findings with potentially major public health implications meriting validation in an experimental intervention study.

  7. The long-term effect of a population-based life-style intervention on smoking and alcohol consumption. The Inter99 Study--a randomized controlled trial.

    Science.gov (United States)

    Baumann, Sophie; Toft, Ulla; Aadahl, Mette; Jørgensen, Torben; Pisinger, Charlotta

    2015-11-01

    To examine whether improvements in smoking and alcohol consumption throughout the 5-year course of a population-based multi-factorial life-style intervention were sustained 5 years after its discontinuation. Population-based randomized controlled trial. Suburbs of Copenhagen, Denmark. A total of 9415 people aged 30-60 years were randomized to an intervention group (n = 6091) and an assessment-only control group (n = 3324). All participants in the intervention group received screening, risk assessment and individual life-style counselling; participants at high risk of ischaemic heart disease-according to pre-specified criteria-were also offered group-based counselling. Self-reported point abstinence from smoking as well as changes in the average alcohol consumption per week and binge drinking in the past week from baseline to 10-year follow-up were investigated using random-effects modelling. At 10-year follow up, people in the intervention group reported a higher smoking abstinence rate [odds ratio (OR) = 1.84, 95% confidence interval (CI) = 1.02-3.33, P = 0.043] and a greater reduction in binge drinking (net change = -0.08 days with binge drinking in the last week, 95% CI = -0.16 to -0.01, P = 0.028) than in the control group. There were no detectable long-term intervention effects on the average alcohol consumption per week. A population-based multi-factorial life-style intervention of 5 years' duration in Denmark had sustained beneficial effects on smoking abstinence and binge drinking 5 years after its discontinuation. © 2015 Society for the Study of Addiction.

  8. Acceptance sampling using judgmental and randomly selected samples

    Energy Technology Data Exchange (ETDEWEB)

    Sego, Landon H.; Shulman, Stanley A.; Anderson, Kevin K.; Wilson, John E.; Pulsipher, Brent A.; Sieber, W. Karl

    2010-09-01

    We present a Bayesian model for acceptance sampling where the population consists of two groups, each with different levels of risk of containing unacceptable items. Expert opinion, or judgment, may be required to distinguish between the high and low-risk groups. Hence, high-risk items are likely to be identifed (and sampled) using expert judgment, while the remaining low-risk items are sampled randomly. We focus on the situation where all observed samples must be acceptable. Consequently, the objective of the statistical inference is to quantify the probability that a large percentage of the unsampled items in the population are also acceptable. We demonstrate that traditional (frequentist) acceptance sampling and simpler Bayesian formulations of the problem are essentially special cases of the proposed model. We explore the properties of the model in detail, and discuss the conditions necessary to ensure that required samples sizes are non-decreasing function of the population size. The method is applicable to a variety of acceptance sampling problems, and, in particular, to environmental sampling where the objective is to demonstrate the safety of reoccupying a remediated facility that has been contaminated with a lethal agent.

  9. Urinary albumin excretion in a population based sample of 1011 middle aged non-diabetic subjects. The Copenhagen City Heart Study Group

    DEFF Research Database (Denmark)

    Jensen, J S; Feldt-Rasmussen, B; Borch-Johnsen, K

    1993-01-01

    in the non-diabetic population. Among 1011 30-70-year-old subjects without diabetes mellitus or urinary tract infection, who were invited to participate in a population based epidemiological study, the albumin concentration was measured in an overnight urine sample. The measurement was performed by an ELISA...... constant with age, but males had higher UAER than females, 2.6 (0-13.5) micrograms min-1 vs 2.2 (0-8.3) micrograms min-1; p sample, was 3% (95% C.I. interval: 1...

  10. Prevalence of fetal alcohol syndrome in a population-based sample of children living in remote Australia: the Lililwan Project.

    Science.gov (United States)

    Fitzpatrick, James P; Latimer, Jane; Carter, Maureen; Oscar, June; Ferreira, Manuela L; Carmichael Olson, Heather; Lucas, Barbara R; Doney, Robyn; Salter, Claire; Try, Julianne; Hawkes, Genevieve; Fitzpatrick, Emily; Hand, Marmingee; Watkins, Rochelle E; Martiniuk, Alexandra L C; Bower, Carol; Boulton, John; Elliott, Elizabeth J

    2015-04-01

    Aboriginal leaders concerned about high rates of alcohol use in pregnancy invited researchers to determine the prevalence of fetal alcohol syndrome (FAS) and partial fetal alcohol syndrome (pFAS) in their communities. Population-based prevalence study using active case ascertainment in children born in 2002/2003 and living in the Fitzroy Valley, in Western Australia (April 2010-November 2011) (n = 134). Socio-demographic and antenatal data, including alcohol use in pregnancy, were collected by interview with 127/134 (95%) consenting parents/care givers. Maternal/child medical records were reviewed. Interdisciplinary assessments were conducted for 108/134 (81%) children. FAS/pFAS prevalence was determined using modified Canadian diagnostic guidelines. In 127 pregnancies, alcohol was used in 55%. FAS or pFAS was diagnosed in 13/108 children, a prevalence of 120 per 1000 (95% confidence interval 70-196). Prenatal alcohol exposure was confirmed for all children with FAS/pFAS, 80% in the first trimester and 50% throughout pregnancy. Ten of 13 mothers had Alcohol Use Disorders Identification Test scores and all drank at a high-risk level. Of children with FAS/pFAS, 69% had microcephaly, 85% had weight deficiency and all had facial dysmorphology and central nervous system abnormality/impairment in three to eight domains. The population prevalence of FAS/pFAS in remote Aboriginal communities of the Fitzroy Valley is the highest reported in Australia and similar to that reported in high-risk populations internationally. Results are likely to be generalisable to other age groups in the Fitzroy Valley and other remote Australian communities with high-risk alcohol use during pregnancy. Prevention of FAS/pFAS is an urgent public health challenge. © 2015 The Authors. Journal of Paediatrics and Child Health © 2015 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  11. Is there a relationship between adverse childhood experiences and problem drinking behaviors? Findings from a population-based sample.

    Science.gov (United States)

    Fang, Lin; McNeil, Sandra

    2017-09-01

    The study investigated the relationships between adverse childhood experiences (ACEs) and heavy and binge drinking, stratified by gender. Population-based cross-sectional study. Data were retrieved from 2012 Behavioral Risk Factor Surveillance System. Over 39,000 individuals from five states were included in the study. Multiple logistic regression models were used to analyze the weighted data to determine factors associated with heavy and binge drinking for men and women. Each model included ACEs and controlled for sociodemographic variables, depression and smoking status. Bonferroni method was used to correct multiple comparisons. Only a few relationships between ACEs and problem drinking were observed. Among men, living with a drug abuser as a child was significantly associated with both heavy and binge drinking compared to men who did not reside with a drug abuser as a child. Childhood verbal abuse was linked with men's binge drinking compared to men who were not verbally abused as children. Among women, none of the nine ACEs examined in the study were associated with their heavy drinking. Only one ACE, verbal abuse, was found to be correlated with binge drinking, compared to women who did not experience childhood verbal abuse. In addition, we did not find the hypothesized, step-wise, graded relationship between the number of ACEs and heavy and binge drinking. However, the risk of heavy drinking was greater if the individual was exposed to four or more childhood adversities among both men and women. Study hypotheses were only partially supported. Future studies should unpack the interplay among gender, socio-economic status, ACEs, and problem alcohol consumption. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  12. Examination of the cut-off scores determined by the Ages and Stages Questionnaire in a population-based sample of 6 month-old Norwegian infants

    Directory of Open Access Journals (Sweden)

    Alvik Astrid

    2011-12-01

    Full Text Available Abstract Background Few population-based samples have previously published performance on the Ages and Stages Questionnaire (ASQ, a recommended screening tool to detect infant developmental delay. The aim of the study was to investigate performance on the ASQ in a population-based sample of 6-month-old infants. Methods In this population-based questionnaire study from Oslo, Norway, the 30 item ASQ 6 month Questionnaire (N = 1053 were included, however without the pictograms, and compared to the Norwegian reference sample (N.ref (N = 169 and to US cut-off values. Exclusion criteria were maternal non-Scandinavian ethnicity, infant age 7.0 months (corrected age, twins, and birth weight Results The reported ASQ scores were lower on all but one of the 10 significantly different items, and in all areas except Personal social, compared to the N.ref sample. The estimated cut-off values for suspected developmental delay (Communication 25, Gross motor 15, Fine motor 18, Problem solving 25 and Personal social 20 were lower than the recommended American (US values in all areas, and lower than the Norwegian values in two areas. Scores indicating need for further assessment were reached by 13.8% or 20.5% of the infants (missing items scored according to the US or the Norwegian manual, and by 33.8% or 30.3% of the infants using the recommended US or the Norwegian cut-off values, in this population-based sample. The Fine motor area demonstrated a large variability depending on the different cut-off and scoring possibilities. Both among the items excluding pictograms and the items that do not have pictograms, approximately every third item differed significantly compared to the N.ref sample. Conclusion The psychomotor developmental scores were lower than in the reference samples in this study of ASQ 6 month Questionnaire; to our knowledge the first study to be both representative and comparatively large. Approximately every third child with birth weight above 2

  13. Evaluating refraction and visual acuity with the Nidek autorefractometer AR-360A in a randomized population-based screening study.

    Science.gov (United States)

    Stoor, Katri; Karvonen, Elina; Liinamaa, Johanna; Saarela, Ville

    2017-11-30

    The evaluation of visual acuity (VA) and refraction in the Northern Finland Birth Cohort Eye study was performed using the Nidek AR-360A autorefractometer. The accuracy of the method for this population-based screening study was assessed. Measurements of the refractive error were obtained from the right eyes of 1238 subjects (mean age 47), first objectively with the AR-360A and then subjectively by an optometrist. Agreement with the subjective refraction was calculated for sphere, cylinder, mean spherical equivalent (MSE), cylindrical vectors J 45 and J 0 and presbyopic correction (add). Visual acuity (VA) was measured using an ETDRS chart and the autorefractometer. The refractive error measured with the AR-360A was higher than the subjective refraction performed by the optometrist for sphere (0.007 D ± 0.24 D p = 0.30) and also for cylinder (-0.16 D ± 0.20 D p refraction. In 99.2% of the measurements, visual values were within one decimal line of each other. The Nidek AR-360A autorefractometer is an accurate tool for determining the refraction and VA in a clinical screening trial. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  14. Association of the dopamine transporter gene and ADHD symptoms in a Canadian population-based sample of same-age twins.

    Science.gov (United States)

    Ouellet-Morin, Isabelle; Wigg, Karen G; Feng, Yu; Dionne, Ginette; Robaey, Philippe; Brendgen, Mara; Vitaro, Frank; Simard, Louise; Schachar, Russell; Tremblay, Richard E; Pérusse, Daniel; Boivin, Michel; Barr, Cathy L

    2008-12-05

    Attention deficit hyperactivity disorder (ADHD) is the most prevalent psychiatric disorder emerging during childhood. Psychostimulant medications (e.g., methylphenidate) noticeably reduce ADHD symptoms in most children. Since methylphenidate inhibits dopamine transporter activity, the dopamine transporter gene (DAT1) was considered to be the prime candidate risk gene in ADHD. Several studies found evidence for an association between the 10-repeat allele of the variable number of tandem repeat (VNTR) located in the 3' untranslated region and ADHD and/or ADHD symptoms in clinical and population-based samples. However, this finding was not replicated in all samples. In this study, we investigated the association between the DAT1 gene and ADHD symptoms in a population-based twin sample from Québec (Canada). We used two polymorphisms, the VNTR and rs27072, the last providing the most significant results in a clinical sample from Toronto (Ontario, Canada). No association was noted between the VNTR and ADHD symptoms in children at 6 and 7 years of age, as reported by teachers. However, a significant association was found for the rs27072 polymorphism and symptoms of inattention and hyperactivity/impulsivity. These findings indicate that the DAT1 gene contributes to ADHD symptoms in this sample and further suggest that the VNTR may not be the optimal polymorphism for study in all populations. Copyright 2007 Wiley-Liss, Inc.

  15. Comparison of sample characteristics in two pregnancy cohorts: community-based versus population-based recruitment methods

    OpenAIRE

    Leung, Brenda MY; Sheila W McDonald; Kaplan, Bonnie J; Giesbrecht, Gerald F.; Tough, Suzanne C.

    2013-01-01

    Background One of the biggest challenges for population health studies is the recruitment of participants. Questions that investigators have asked are “who volunteers for studies?” and “does recruitment method influence characteristics of the samples?” The purpose of this paper was to compare sample characteristics of two unrelated pregnancy cohort studies taking place in the same city, in the same time period, that employed different recruitment strategies, as well as to compare the characte...

  16. Smoking, alcohol consumption, and drug use among adolescents with psychiatric disorders compared with a population based sample.

    Science.gov (United States)

    Mangerud, Wenche Langfjord; Bjerkeset, Ottar; Holmen, Turid Lingaas; Lydersen, Stian; Indredavik, Marit Sæbø

    2014-10-01

    This study investigated frequencies of smoking, alcohol use, and illicit drug use by diagnostic category in 566 adolescent psychiatric patients, comparing this sample with 8173 adolescents from the general population in Norway who completed the Young-HUNT 3 survey. Frequencies of current alcohol use were high in both samples but were lower among psychiatric patients. Compared with adolescents in the general population, adolescents in the clinical sample had a higher prevalence of current smoking and over four times higher odds of having tried illicit drugs. In the clinical sample, those with mood disorders reported the highest frequencies of smoking, alcohol use, and illicit drug use, whereas those with autism spectrum disorders reported the lowest frequencies. Our results show an increased prevalence of risky health behaviors among adolescents with psychiatric disorders compared with the general population. The awareness of disorder-specific patterns of smoking and substance use may guide preventive measures. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Comparing Data Characteristics and Results of an Online Factorial Survey between a Population-Based and a Crowdsource-Recruited Sample

    Directory of Open Access Journals (Sweden)

    Jill D. Weinberg

    2014-08-01

    Full Text Available Compared to older kinds of sample surveys, online platforms provide a fast and low-cost platform for factorial surveys, as well as a more demographically diverse alternative to student samples. Two distinct strategies have emerged for recruitment: using panels based on population-based samples versus recruiting people actively seeking to complete online tasks for money. The latter is much cheaper but prompts various concerns about data quality and generalizability. We compare results of three vignette experiments conducted using the leading online panel that uses a population-based paradigm (Knowledge Networks, now GfK and the leading platform for crowdsource recruitment (Amazon Mechanical Turk. Our data show that, while demographic differences exist, most notably in age, the actual results of our experiments are very similar, especially once these demographic differences have been taken into account. Indicators of data quality were actually slightly better among the crowdsource subjects. Although more evidence is plainly needed, our results support the accumulating evidence for the promise of crowdsource recruitment for online experiments, including factorial surveys.

  18. Association between depressive symptoms in adolescence and birth outcomes in early adulthood using a population-based sample

    OpenAIRE

    Nkansah-Amankra, Stephen; Tettey, Grace

    2015-01-01

    Background: Adolescent female depressive symptomatology is an unrecognized mood disorder that impairs health in adolescence or adulthood. However, the long-term effects of pre-pregnancy depressive symptoms on birth outcomes in adulthood have not been given adequate empirical assessments. Method: In this study, we assessed the relationship between the life time duration of depressive symptoms over a 14-year period and birth outcomes (LBW and PTB) among a sample of 6023 female respondents wh...

  19. Depressive disorders and panic attacks in women with bladder pain syndrome/interstitial cystitis: a population-based sample.

    Science.gov (United States)

    Watkins, Katherine E; Eberhart, Nicole; Hilton, Lara; Suttorp, Marika J; Hepner, Kimberly A; Clemens, J Quentin; Berry, Sandra H

    2011-01-01

    We report the population prevalence of probable depressive disorders and current panic attacks in women with bladder pain syndrome/interstitial cystitis (BPS/IC) symptoms and describe their characteristics and access care. We conducted a telephone screening of 146,231 households and telephone interviews with women with BPS/IC symptoms. A weighted probability sample of 1469 women who met the criteria for BPS/IC was identified. Measures of BPS/IC severity, depressive symptoms, panic attacks and treatment utilization were administered. T and χ(2) tests were used to examine differences between groups. Over one third of the sample (n=536) had a probable diagnosis of depression, and 52% (n=776) reported recent panic attacks. Women with a probable diagnosis of depression or current panic attacks reported worse functioning and increased pain and were less likely to work because of bladder pain. In this community-based sample, rates of probable current depression and panic attacks are high, and there is considerable unmet need for treatment. These findings suggest that clinicians should be alert to complaints of bladder pain in patients seeking treatment for depressive or anxiety disorders and to complaints of emotional or personal problems in patients seeking treatment for painful bladder symptoms. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Prevalence and associations of anisometropia and aniso-astigmatism in a population based sample of 6 year old children.

    Science.gov (United States)

    Huynh, S C; Wang, X Y; Ip, J; Robaei, D; Kifley, A; Rose, K A; Mitchell, P

    2006-05-01

    To study the distribution of anisometropia and aniso-astigmatism in young Australian children, together with clinical and ocular biometry relations. The Sydney Myopia Study examined 1765 predominantly 6 year old children from 34 randomly selected Sydney schools during 2003-4. Keratometry, cycloplegic autorefraction, and questionnaire data were collected. Spherical equivalent (SE) anisometropia (> or =1 dioptre) prevalence was 1.6% (95% confidence interval (CI) 1.1% to 2.4%). Aniso-astigmatism (>or =1D) prevalence was 1.0% (CI: 0.6% to 1.6%). Both conditions were significantly more prevalent among moderately hyperopic (SE > or =2.0D) than mildly hyperopic (SE 0.5-1.9D) children. Myopic children (SE anisometropia prevalence. Neither condition varied by age, sex, or ethnicity. In multivariate analyses, anisometropia was significantly associated with amblyopia, odds ratio (OR) 29, (CI: 8.7 to 99), exotropia (OR 7.7, CI: 1.2 to 50), and neonatal intensive care unit (NICU) admission (OR 3.6, CI: 1.1 to 12.6). Aniso-astigmatism was significantly associated with amblyopia (OR 8.2, CI: 1.4 to 47), maternal age >35 years (OR 4.0, CI: 1.3 to 11.9), and NICU admission (OR 4.6, CI: 1.2 to 17.2). Anisometropia resulted from relatively large interocular differences in axial length (panisometropia and aniso-astigmatism were uncommon, had important birth and biometry associations, and were strongly related to amblyopia and strabismus.

  1. Knowledge and Attitudes towards Antibiotic Use and Resistance - A Latent Class Analysis of a Swedish Population-Based Sample

    Science.gov (United States)

    Rosales-Klintz, Senia; Tegmark Wisell, Karin; Stålsby Lundborg, Cecilia

    2016-01-01

    Background In 2006, a study investigating knowledge and attitudes regarding antibiotic use and resistance in Sweden, indicated high level of knowledge but also areas in need of improvement. Objective (i) To provide an update on the knowledge and attitudes to antibiotic use and resistance of the Swedish population, and (ii) to identify which groups within the population are in particular need of improved knowledge or attitudes. Methods A questionnaire was sent by post in 2013 to 2,500 randomly-selected individuals aged 18–74, living in Sweden. Latent class analyses were conducted to group respondents based on their responses. The association between socio-demographic characteristics and the probability of belonging to each latent class was assessed. Results The response rate was 57%. Ninety-four per cent of the responders knew that bacteria could become resistant to antibiotics and the majority answered correctly to the questions regarding antibiotic resistance development. The respondents expressed confidence in doctors who decided not to prescribe antibiotics. Three latent classes related to ‘knowledge regarding antibiotic use and resistance’, two regarding ‘attitudes towards antibiotic accessibility and infection prevention’ and three regarding ‘attitudes towards antibiotic use and effects’ were revealed. Men, younger and more educated people were more knowledgeable but males had a less restrictive attitude. Respondents with high levels of knowledge on antibiotics were more likely to have appropriate restrictive attitudes to antibiotics. Conclusion Knowledge on antibiotic use and resistance is maintained high and has improved in Sweden compared to 2006. People with lower education and elderly are especially in need of improved knowledge about antibiotic use and resistance. PMID:27096751

  2. Knowledge and Attitudes towards Antibiotic Use and Resistance - A Latent Class Analysis of a Swedish Population-Based Sample.

    Directory of Open Access Journals (Sweden)

    Martina Vallin

    Full Text Available In 2006, a study investigating knowledge and attitudes regarding antibiotic use and resistance in Sweden, indicated high level of knowledge but also areas in need of improvement.(i To provide an update on the knowledge and attitudes to antibiotic use and resistance of the Swedish population, and (ii to identify which groups within the population are in particular need of improved knowledge or attitudes.A questionnaire was sent by post in 2013 to 2,500 randomly-selected individuals aged 18-74, living in Sweden. Latent class analyses were conducted to group respondents based on their responses. The association between socio-demographic characteristics and the probability of belonging to each latent class was assessed.The response rate was 57%. Ninety-four per cent of the responders knew that bacteria could become resistant to antibiotics and the majority answered correctly to the questions regarding antibiotic resistance development. The respondents expressed confidence in doctors who decided not to prescribe antibiotics. Three latent classes related to 'knowledge regarding antibiotic use and resistance', two regarding 'attitudes towards antibiotic accessibility and infection prevention' and three regarding 'attitudes towards antibiotic use and effects' were revealed. Men, younger and more educated people were more knowledgeable but males had a less restrictive attitude. Respondents with high levels of knowledge on antibiotics were more likely to have appropriate restrictive attitudes to antibiotics.Knowledge on antibiotic use and resistance is maintained high and has improved in Sweden compared to 2006. People with lower education and elderly are especially in need of improved knowledge about antibiotic use and resistance.

  3. The prevalence of compulsive hoarding and its association with compulsive buying in a German population-based sample.

    Science.gov (United States)

    Mueller, Astrid; Mitchell, James E; Crosby, Ross D; Glaesmer, Heide; de Zwaan, Martina

    2009-08-01

    The aims of the study were to estimate the prevalence rate of compulsive hoarding, and to determine the association between compulsive hoarding and compulsive buying in a nationally representative sample of the German population (N = 2307). Compulsive hoarding was assessed with the German version of the Saving Inventory-Revised (SI-R; Frost, R.O., Steketee, G., & Grisham, J. (2004). Measurement of compulsive hoarding: saving inventory-revised. Behaviour Research and Therapy, 42, 1163-1182.). The point prevalence of compulsive hoarding was estimated to be 4.6%. Individuals with compulsive hoarding did not differ significantly from those without compulsive hoarding regarding age, gender, and other sociodemographic characteristics. Significant correlations were found between the compulsive hoarding and the compulsive buying measures. Participants with compulsive hoarding reported a higher propensity to compulsive buying than respondents without hoarding. About two thirds of participants classified as having compulsive hoarding were also defined as suffering from compulsive buying. In summary, these results suggest that compulsive hoarding may be relatively prevalent in Germany and they confirm the close association between compulsive hoarding and compulsive buying through the investigation of a large scale representative sample.

  4. GSAMPLE: Stata module to draw a random sample

    OpenAIRE

    Jann, Ben

    2006-01-01

    gsample draws a random sample from the data in memory. Simple random sampling (SRS) is supported, as well as unequal probability sampling (UPS), of which sampling with probabilities proportional to size (PPS) is a special case. Both methods, SRS and UPS/PPS, provide sampling with replacement and sampling without replacement. Furthermore, stratified sampling and cluster sampling is supported.

  5. Tailored telephone counselling to increase participation of underusers in a population-based colorectal cancer-screening programme with faecal occult blood test: A randomized controlled trial.

    Science.gov (United States)

    Denis, B; Broc, G; Sauleau, E A; Gendre, I; Gana, K; Perrin, P

    2017-02-01

    Despite the involvement of general practitioners, the mailing of several recall letters and of the faecal occult blood test (FOBT) kit, the uptake remains insufficient in the French colorectal cancer-screening programme. Some studies have demonstrated a greater efficacy of tailored telephone counselling over usual care, untailored invitation mailing and FOBT kit mailing. We evaluated the feasibility and the effectiveness of telephone counselling on participation in the population-based FOBT colorectal cancer-screening programme implemented in Alsace (France). Underusers were randomized into a control group with untailored invitation and FOBT kit mailing (n=19,756) and two intervention groups for either a computer-assisted telephone interview (n=9367), system for tailored promotion of colorectal cancer screening, or a telephone-based motivational interview (n=9374). Only 5691 (19.9%) people were actually counseled, so that there was no difference in participation between the intervention groups taken together (13.9%, 95% confidence interval [CI] [13.5-14.4]) and the control group (13.9%, 95% CI [13.4-14.4]) (P=1.0) in intent-to-treat analysis. However, in per-protocol analysis, participation was significantly higher in the two intervention groups than in the control group (12.9%, 95% CI [12.6-13.2]) (Pcounselling and untailored invitation and FOBT kit mailing on participation of underusers in an organized population-based colorectal cancer screening programme. A greater efficacy of telephone counselling, around twice that of invitation and FOBT kit mailing, was observed only in people who could actually be counseled, without difference between computer-assisted telephone interview and motivational interview. However, technical failures hampered telephone counselling, so that there was no difference in intent-to-treat analysis. The rate of technical success of telephone interviews should be evaluated, and enhanced if insufficient, before implementation of telephone

  6. Four-year longitudinal performance of a population-based sample of healthy children on a neuropsychological battery: the NIH MRI study of normal brain development.

    Science.gov (United States)

    Waber, Deborah P; Forbes, Peter W; Almli, C Robert; Blood, Emily A

    2012-03-01

    The National Institutes of Health (NIH) Magnetic Resonance Imaging (MRI) Study of Normal Brain Development is a landmark study in which structural and metabolic brain development and behavior are followed longitudinally from birth to young adulthood in a population-based sample of healthy children. Cross-sectional findings from the neuropsychological test battery have been previously described (Waber et al., 2007). The present report details 4-year longitudinal neuropsychological outcomes for those children who were aged 6 to 18 years at baseline (N = 383), of whom 219 (57.2%) completed all 3 visits. Primary observations were (1) individual children displayed considerable variation in scores across visits on the same measures; (2) income-related differences were more prominent in the longitudinal than in the cross-sectional data; (3) no association between cognitive and behavioral measures and body mass index; and (4) several measures showed practice effects, despite the 2-year interval between visits. These data offer an unparalleled opportunity to observe normative performance and change over time on a set of standard and commonly used neuropsychological measures in a population-based sample of healthy children. They thus provide important background for the use and interpretation of these instruments in both research settings and clinical practice.

  7. Potentially traumatic events and the risk of six physical health conditions in a population-based sample.

    Science.gov (United States)

    Keyes, Katherine M; McLaughlin, Katie A; Demmer, Ryan T; Cerdá, Magdalena; Koenen, Karestan C; Uddin, Monica; Galea, Sandro

    2013-05-01

    Potentially traumatic events (PTEs) are common in the population, yet, the impact of total burden and specific types of PTEs on physical health has not been systematically investigated. Data were drawn from the Detroit Neighborhood Health Study, a community sample of predominately African Americans living in Detroit, Michigan, interviewed in 2008-2009 (N = 1,547) and in 2009-2010 (N = 1,054). Kaplan-Meier and Cox proportional hazards models were used. Respondents with the highest levels of PTE exposure (8+ events) had an average age of adverse physical health condition diagnosis that was 15 years earlier than respondents with no exposure. There was a monotonic relation between number of PTEs and arthritis risk. Compared to those who reported no lifetime events, respondents with 1-2, 3-4, 5-7, and 8+ traumatic events had 1.06, 1.12, 1.73, and 2.44 times the hazard of arthritis. Assaultive violence (HR = 1.7; 95% CI 1.2-2.3) and other threats to physical integrity (HR = 1.5, 95% CI 1.1-2.1) were particularly strong risk factors for arthritis. These results provide novel evidence linking PTEs, particularly those involving violence and threat to life, to elevated risk for arthritic conditions. Efforts to prevent or mitigate traumatic event exposures may have a broad range of benefits for health. © 2013 Wiley Periodicals, Inc.

  8. Association between depressive symptoms in adolescence and birth outcomes in early adulthood using a population-based sample.

    Science.gov (United States)

    Nkansah-Amankra, Stephen; Tettey, Grace

    2015-01-01

    Adolescent female depressive symptomatology is an unrecognized mood disorder that impairs health in adolescence or adulthood. However, the long-term effects of pre-pregnancy depressive symptoms on birth outcomes in adulthood have not been given adequate empirical assessments. In this study, we assessed the relationship between the life time duration of depressive symptoms over a 14-year period and birth outcomes (LBW and PTB) among a sample of 6023 female respondents who took part in the National Longitudinal Study of Adolescent to Adult Health (Add Health). We used the generalized estimating equation (GEE) models to assess these relationships. Exposure to elevated depressive symptoms in late adolescence, but not in adulthood, was associated with increased odds of LBW by more than 2-fold in early and young adulthoods (adjusted odds ratio [aOR] = 2.19; 95% confidence interval, CI: 1.56, 3.08). Depressive symptoms in early adulthood were independently associated with increased odds of PTB and were higher for black mothers. Maternal race modified the relationship between consistent reporting of depressive symptoms in adolescence and LBW or PTB in adulthood. This study provides compelling evidence that effects of elevated depressive symptomatology on LBW or PTB appear to be linked to a specific development period in adolescence. National policies to address social inequalities and stratification particularly in health at all stages of human development, will provide an important step in reducing depressive symptoms prior to early adulthood and in pregnancy and childbirth.

  9. Health Literacy and Health-Related Quality of Life Among a Population-Based Sample of Cancer Patients.

    Science.gov (United States)

    Halverson, Julie L; Martinez-Donate, Ana P; Palta, Mari; Leal, Ticiana; Lubner, Sam; Walsh, Matthew C; Schaaf Strickland, Jeanne; Smith, Paul D; Trentham-Dietz, Amy

    2015-01-01

    Health-related quality of life is an important outcome in cancer care. A few studies indicate that health literacy influences cancer patients' health-related quality of life, but additional investigation is needed. The authors examined the relation between health literacy and health-related quality of life among cancer patients. A cross-sectional survey was conducted with cancer patients in Wisconsin during 2006-2007. Data on sociodemographics, clinical characteristics, health-related quality of life, and health literacy were obtained from the state's cancer registry and a mailed questionnaire. Regression analyses were used to characterize the association between health-related quality of life and health literacy. The study sample included 1,841 adults, newly diagnosed with lung, breast, colorectal, or prostate cancer in 2004 (response rate = 68%). Health-related quality of life was measured with the Functional Assessment of Cancer Therapy-General. Adjusting for confounders, higher health literacy was associated with greater health-related quality of life (p literacy categories (p emotional (p literacy is positively and independently associated with health-related quality of life among cancer patients. These findings support adoption of health literacy best practices by cancer care systems.

  10. Non-attendance of mammographic screening: the roles of age and municipality in a population-based Swedish sample.

    Science.gov (United States)

    Zidar, Maria Norfjord; Larm, Peter; Tillgren, Per; Akhavan, Sharareh

    2015-12-30

    Inequality in health and health care is increasing in Sweden. Contributing to widening gaps are various factors that can be assessed by determinants, such as age, educational level, occupation, living area and country of birth. A health care service that can be used as an indicator of health inequality in Sweden is mammographic screening. The non-attendance rate is between 13 and 31 %, while the average is about 20 %. This study aims to shed light on three associations: between municipality and non-attendance, between age and non-attendance, and the interaction of municipality of residence and age in relation to non-attendance. The study is based on data from the register that identifies attenders and non-attenders of mammographic screening in a Swedish county, namely the Radiological Information System (RIS). Further, in order to provide a socio-demographic profile of the county's municipalities, aggregated data for women in the age range 40-74 in 2012 were retrieved from Statistics Sweden (SCB), the Public Health Agency of Sweden, the National Board of Health and Welfare, and the Swedish Social Insurance Agency. The sample consisted of 52,541 women. Analysis conducted of the individual data were multivariate logistic regressions, and pairwise chi-square tests. The results show that age and municipality of residence associated with non-attendance of mammographic screening. Municipality of residence has a greater impact on non-attendance among women in the age group 70 to 74. For most of the age categories there were differences between the municipalities in regard to non-attendance to mammographic screening. Age and municipality of residence affect attendance of mammographic screening. Since there is one sole and pre-selected mammographic screening facility in the county, distance to the screening facility may serve as one explanation to non-attendance which is a determinant of inequity. From an equity perspective, lack of equal access to health and health care

  11. Suicidality and sexual orientation: differences between men and women in a general population-based sample from the Netherlands.

    Science.gov (United States)

    de Graaf, Ron; Sandfort, Theo G M; ten Have, Margreet

    2006-06-01

    Homosexuality has been shown to be associated with suicidality and mental disorders. It is unclear whether homosexuality is related to suicidality, independently of mental disorders. This study assessed differences in lifetime symptoms of suicidality (death ideation, death wishes, suicide contemplation, and deliberate self-harm) between homosexual and heterosexual men and women, controlling for lifetime psychiatric morbidity. Interaction effects of age and the role of perceived discrimination were also examined. Data were collected on a representative sample of the Dutch population aged 18-64 years. Classification as heterosexual or homosexual was based upon reported sexual behavior in the preceding year. Of those sexually active, 2.8% of 2,878 men and 1.4% of 3,120 women had had same-sex partners. Homosexual men differed from their heterosexual counterparts on all four suicide symptoms (OR ranging from 2.58 to 10.23, with higher ORs for more severe symptoms), and on the sum total of the four symptoms; homosexual women only differed from heterosexual women on suicide contemplation (OR=2.12). Controlling for psychiatric morbidity decreased the ORs, but among men all associations were still significant; the significance for suicide contemplation among women disappeared. Younger homosexuals were not at lower risk for suicidality than older homosexuals in comparison with their heterosexual counterparts. Among homosexual men, perceived discrimination was associated with suicidality. This study suggests that even in a country with a comparatively tolerant climate regarding homosexuality, homosexual men were at much higher risk for suicidality than heterosexual men. This relationship could not only be attributed to their higher psychiatric morbidity. In women, there was no such clear relationship.

  12. Metabolic Syndrome and Associated Factors in a Population-Based Sample of Schoolchildren in Colombia: The FUPRECOL Study.

    Science.gov (United States)

    Ramírez-Vélez, Robinson; Anzola, Alejandro; Martinez-Torres, Javier; Vivas, Andres; Tordecilla-Sanders, Alejandra; Prieto-Benavides, Daniel; Izquierdo, Mikel; Correa-Bautista, Jorge Enrique; Garcia-Hermoso, Antonio

    2016-11-01

    In contrast to the definition of metabolic syndrome (MetS) in adults, there is no standard definition of MetS in pediatric populations. We aimed at assessing the differences in the prevalence of MetS in children and adolescents aged 9-17 years using four different operational definitions for these age groups and at examining the associated variables. A total of 675 children and 1247 adolescents attending public schools in Bogota (54.4% girls; age range 9-17.9 years) were included. The prevalence of MetS was determined by the definitions provided by the International Diabetes Federation (IDF) and three published studies by Cook et al., de Ferranti et al., and Ford et al. In addition, we further examined the associations between each definition of MetS in the total sample and individual risk factors using binary logistic regression models adjusted for gender, age, pubertal stage, weight status, and inflammation in all participants. The prevalence of MetS was 0.3%, 6.3%, 7.8%, and 11.0% according to the definitions by IDF, Cook et al., Ford et al., and de Ferranti et al., respectively. The most prevalent components were low high-density lipoprotein cholesterol and high triglyceride levels, whereas the least prevalent components were higher waist circumference and hyperglycemia. Overall, the prevalence of MetS was higher in obese than in non-obese schoolchildren. MetS diagnoses in schoolchildren strongly depend on the definition chosen. These findings may be relevant to health promotion efforts for Colombian youth to develop prospective studies and to define which cut-offs are the best indicators of future morbidity.

  13. Gamified physical activation of young men – a Multidisciplinary Population-Based Randomized Controlled Trial (MOPO study

    Directory of Open Access Journals (Sweden)

    Ahola Riikka

    2013-01-01

    Full Text Available Abstract Background Inactive and unhealthy lifestyles are common among adolescent men. The planned intervention examines the effectiveness of an interactive, gamified activation method, based on tailored health information, peer networks and participation, on physical activity, health and wellbeing in young men. We hypothesize that following the intervention the physical activation group will have an improved physical activity, as well as self-determined and measured health compared with the controls. Methods/design Conscription-aged men (18 years attending compulsory annual call-ups for military service in the city of Oulu in Finland (n = 1500 will be randomized to a 6-months intervention (n = 640 or a control group (n = 640 during the fall 2013. A questionnaire on health, health behaviour, diet and wellbeing is administered in the beginning and end of the intervention. In addition, anthropometric measures (height, weight and waist circumference, body composition, grip strength, heart rate variability and aerobic fitness will be measured. The activation group utilizes an online gamified activation method in combination with communal youth services, objective physical activity measurement, social networking, tailored health information and exercise programs according to baseline activity level and the readiness of changes of each individual. Daily physical activity of the participants is monitored in both the activation and control groups. The activation service rewards improvements in physical activity or reductions in sedentary behaviour. The performance and completion of the military service of the participants will also be followed. Discussion The study will provide new information of physical activity, health and health behaviour of young men. Furthermore, a novel model including methods for increasing physical activity among young people is developed and its effects tested through an intervention. This unique gamified service

  14. Moving on: Factors associated with caregivers' bereavement adjustment using a random population-based face-to-face survey.

    Science.gov (United States)

    Burns, Emma; Prigerson, Holly G; Quinn, Steve J; Abernethy, Amy P; Currow, David C

    2017-06-01

    Providing care at end of life has consequences for caregivers' bereavement experience. 'Difficulty moving on with life' is an informative and unbiased symptom of prolonged grief disorder. Predictors of bereaved caregivers' ability to 'move on' have not been examined across the population. To identify the characteristics of bereaved hands-on caregivers who were, and were not, able to 'move on' 13-60 months after the 'expected' death of someone close. The South Australian Health Omnibus is an annual, random, cross-sectional community survey. From 2000 to 2007, respondents were asked about providing care for someone terminally ill and their subsequent ability to 'move on'. Multivariable logistic regression models explored the characteristics moving on and not moving on. Respondents were aged ⩾15 years and lived in households within South Australia. They had provided care to someone who had died of terminal illness in the preceding 5 years. A total of 922 people provided hands-on care. In all, 80% of caregivers (745) had been able to 'move on'. Closeness of relationship to the deceased, increasing caregiver age, caregiver report of needs met, increasing time since loss, sex and English-speaking background were significantly associated with 'moving on'. A closer relationship to the deceased, socioeconomic disadvantage and being male were significantly associated with not 'moving on'. These results support the relevance of 'moving on' as an indicator of caregivers' bereavement adjustment. Following the outcomes of bereaved caregivers longitudinally is essential if effective interventions are to be developed to minimise the risk of prolonged grief disorder.

  15. Backlog and burden of fractures in Sierra Leone and Nepal: Results from nationwide cluster randomized, population-based surveys.

    Science.gov (United States)

    Stewart, Barclay T; Kushner, Adam L; Kamara, Thaim B; Shrestha, Sunil; Gupta, Shailvi; Groen, Reinou S; Nwomeh, Ben; Gosselin, Richard A; Spiegel, David

    2016-09-01

    The burden of injury is increasing worldwide; planning for its impact on population health and health systems is urgently needed, particularly in low- and middle-income countries (LMICs). This study aimed to model the burden of fractures and project costs to eliminate avertable fracture-related disability-adjusted life-years (i.e., a measure of overall disease burden, expressed as the number of years lost due to ill-health, disability or premature death; DALYs) in Sierra Leone and Nepal. Data from nationwide, cluster-randomized, community-based surveys of surgical need in Sierra Leone and Nepal were used to model the incidence and prevalence of fractures stratified by met and unmet needs. DALYs incurred from treated and untreated fractures were estimated. Additionally, the investment necessary to eliminate avertable incident fracture DALYs was modeled through 2025 using published cost per DALY averted estimates. The incidence of treated and untreated fractures in Sierra Leone was 570 and 1004 fractures per 100,000 persons, respectively. There could be more than 2 million avertable fracture DALYs by 2025 in Sierra Leone and 2.5 million in Nepal requiring an estimated US$ 4,049,932 (range US$ 2,011,500-6,088,364) and US$ 4,962,402 (range US$ 2,464,701-7,460,103) to address this excess burden, respectively. This study identified a significant burden of untreated fractures in both countries, and an opportunity to avert more than 4.5 million DALYs in 10 years in a cost-effective manner. Prioritizing funding mechanisms for orthopaedic care and implants should be considered given the large burden of untreated fractures found in both countries and the long-term savings and functional benefit from properly treated fractures. Copyright © 2016. Published by Elsevier Ltd.

  16. Diets and selected lifestyle practices of self-defined adult vegetarians from a population-based sample suggest they are more 'health conscious'

    Directory of Open Access Journals (Sweden)

    Barr Susan I

    2005-04-01

    Full Text Available Abstract Background Few population-based studies of vegetarians have been published. Thus we compared self-reported vegetarians to non-vegetarians in a representative sample of British Columbia (BC adults, weighted to reflect the BC population. Methods Questionnaires, 24-hr recalls and anthropometric measures were completed during in-person interviews with 1817 community-dwelling residents, 19–84 years, recruited using a population-based health registry. Vegetarian status was self-defined. ANOVA with age as a covariate was used to analyze continuous variables, and chi-square was used for categorical variables. Supplement intakes were compared using the Mann-Whitney test. Results Approximately 6% (n = 106 stated that they were vegetarian, and most did not adhere rigidly to a flesh-free diet. Vegetarians were more likely female (71% vs. 49%, single, of low-income status, and tended to be younger. Female vegetarians had lower BMI than non-vegetarians (23.1 ± 0.7 (mean ± SE vs. 25.7 ± 0.2 kg/m2, and also had lower waist circumference (75.0 ± 1.5 vs. 79.8 ± 0.5 cm. Male vegetarians and non-vegetarians had similar BMI (25.9 ± 0.8 vs. 26.7 ± 0.2 kg/m2 and waist circumference (92.5 ± 2.3 vs. 91.7 ± 0.4 cm. Female vegetarians were more physically active (69% vs. 42% active ≥4/wk while male vegetarians were more likely to use nutritive supplements (71% vs. 51%. Energy intakes were similar, but vegetarians reported higher % energy as carbohydrate (56% vs. 50%, and lower % protein (men only; 13% vs. 17% or % fat (women only; 27% vs. 33%. Vegetarians had higher fiber, magnesium and potassium intakes. For several other nutrients, differences by vegetarian status differed by gender. The prevalence of inadequate magnesium intake (% below Estimated Average Requirement was lower in vegetarians than non-vegetarians (15% vs. 34%. Female vegetarians also had a lower prevalence of inadequate thiamin, folate, vitamin B6 and C intakes. Vegetarians were

  17. Diets and selected lifestyle practices of self-defined adult vegetarians from a population-based sample suggest they are more 'health conscious'

    Science.gov (United States)

    Bedford, Jennifer L; Barr, Susan I

    2005-04-13

    BACKGROUND: Few population-based studies of vegetarians have been published. Thus we compared self-reported vegetarians to non-vegetarians in a representative sample of British Columbia (BC) adults, weighted to reflect the BC population. METHODS: Questionnaires, 24-hr recalls and anthropometric measures were completed during in-person interviews with 1817 community-dwelling residents, 19-84 years, recruited using a population-based health registry. Vegetarian status was self-defined. ANOVA with age as a covariate was used to analyze continuous variables, and chi-square was used for categorical variables. Supplement intakes were compared using the Mann-Whitney test. RESULTS: Approximately 6% (n = 106) stated that they were vegetarian, and most did not adhere rigidly to a flesh-free diet. Vegetarians were more likely female (71% vs. 49%), single, of low-income status, and tended to be younger. Female vegetarians had lower BMI than non-vegetarians (23.1 +/- 0.7 (mean +/- SE) vs. 25.7 +/- 0.2 kg/m2), and also had lower waist circumference (75.0 +/- 1.5 vs. 79.8 +/- 0.5 cm). Male vegetarians and non-vegetarians had similar BMI (25.9 +/- 0.8 vs. 26.7 +/- 0.2 kg/m2) and waist circumference (92.5 +/- 2.3 vs. 91.7 +/- 0.4 cm). Female vegetarians were more physically active (69% vs. 42% active >/=4/wk) while male vegetarians were more likely to use nutritive supplements (71% vs. 51%). Energy intakes were similar, but vegetarians reported higher % energy as carbohydrate (56% vs. 50%), and lower % protein (men only; 13% vs. 17%) or % fat (women only; 27% vs. 33%). Vegetarians had higher fiber, magnesium and potassium intakes. For several other nutrients, differences by vegetarian status differed by gender. The prevalence of inadequate magnesium intake (% below Estimated Average Requirement) was lower in vegetarians than non-vegetarians (15% vs. 34%). Female vegetarians also had a lower prevalence of inadequate thiamin, folate, vitamin B6 and C intakes. Vegetarians were more

  18. Generation and Analysis of Constrained Random Sampling Patterns

    DEFF Research Database (Denmark)

    Pierzchlewski, Jacek; Arildsen, Thomas

    2016-01-01

    Random sampling is a technique for signal acquisition which is gaining popularity in practical signal processing systems. Nowadays, event-driven analog-to-digital converters make random sampling feasible in practical applications. A process of random sampling is defined by a sampling pattern, whi...

  19. Emotional and tangible social support in a German population-based sample: Development and validation of the Brief Social Support Scale (BS6).

    Science.gov (United States)

    Beutel, Manfred E; Brähler, Elmar; Wiltink, Jörg; Michal, Matthias; Klein, Eva M; Jünger, Claus; Wild, Philipp S; Münzel, Thomas; Blettner, Maria; Lackner, Karl; Nickels, Stefan; Tibubos, Ana N

    2017-01-01

    Aim of the study was the development and validation of the psychometric properties of a six-item bi-factorial instrument for the assessment of social support (emotional and tangible support) with a population-based sample. A cross-sectional data set of N = 15,010 participants enrolled in the Gutenberg Health Study (GHS) in 2007-2012 was divided in two sub-samples. The GHS is a population-based, prospective, observational single-center cohort study in the Rhein-Main-Region in western Mid-Germany. The first sub-sample was used for scale development by performing an exploratory factor analysis. In order to test construct validity, confirmatory factor analyses were run to compare the extracted bi-factorial model with the one-factor solution. Reliability of the scales was indicated by calculating internal consistency. External validity was tested by investigating demographic characteristics health behavior, and distress using analysis of variance, Spearman and Pearson correlation analysis, and logistic regression analysis. Based on an exploratory factor analysis, a set of six items was extracted representing two independent factors. The two-factor structure of the Brief Social Support Scale (BS6) was confirmed by the results of the confirmatory factor analyses. Fit indices of the bi-factorial model were good and better compared to the one-factor solution. External validity was demonstrated for the BS6. The BS6 is a reliable and valid short scale that can be applied in social surveys due to its brevity to assess emotional and practical dimensions of social support.

  20. Emotional and tangible social support in a German population-based sample: Development and validation of the Brief Social Support Scale (BS6.

    Directory of Open Access Journals (Sweden)

    Manfred E Beutel

    Full Text Available Aim of the study was the development and validation of the psychometric properties of a six-item bi-factorial instrument for the assessment of social support (emotional and tangible support with a population-based sample. A cross-sectional data set of N = 15,010 participants enrolled in the Gutenberg Health Study (GHS in 2007-2012 was divided in two sub-samples. The GHS is a population-based, prospective, observational single-center cohort study in the Rhein-Main-Region in western Mid-Germany. The first sub-sample was used for scale development by performing an exploratory factor analysis. In order to test construct validity, confirmatory factor analyses were run to compare the extracted bi-factorial model with the one-factor solution. Reliability of the scales was indicated by calculating internal consistency. External validity was tested by investigating demographic characteristics health behavior, and distress using analysis of variance, Spearman and Pearson correlation analysis, and logistic regression analysis. Based on an exploratory factor analysis, a set of six items was extracted representing two independent factors. The two-factor structure of the Brief Social Support Scale (BS6 was confirmed by the results of the confirmatory factor analyses. Fit indices of the bi-factorial model were good and better compared to the one-factor solution. External validity was demonstrated for the BS6. The BS6 is a reliable and valid short scale that can be applied in social surveys due to its brevity to assess emotional and practical dimensions of social support.

  1. The relationship between the Five-Factor Model personality traits and peptic ulcer disease in a large population-based adult sample.

    Science.gov (United States)

    Realo, Anu; Teras, Andero; Kööts-Ausmees, Liisi; Esko, Tõnu; Metspalu, Andres; Allik, Jüri

    2015-12-01

    The current study examined the relationship between the Five-Factor Model personality traits and physician-confirmed peptic ulcer disease (PUD) diagnosis in a large population-based adult sample, controlling for the relevant behavioral and sociodemographic factors. Personality traits were assessed by participants themselves and by knowledgeable informants using the NEO Personality Inventory-3 (NEO PI-3). When controlling for age, sex, education, and cigarette smoking, only one of the five NEO PI-3 domain scales - higher Neuroticism - and two facet scales - lower A1: Trust and higher C1: Competence - made a small, yet significant contribution (p factors for the development of PUD. © 2015 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  2. Patterns and predictors of survivorship clinic attendance in a population-based sample of pediatric and young adult childhood cancer survivors.

    Science.gov (United States)

    Zheng, Daniel J; Sint, Kyaw; Mitchell, Hannah-Rose; Kadan-Lottick, Nina S

    2016-06-01

    Because many survivors do not receive recommended follow-up, we sought to characterize patterns and predictors of survivorship clinic attendance in a population-based sample of childhood cancer survivors. Using the Connecticut Tumor Registry, we identified all patients diagnosed with cancer at age ≤ 18 years from March 1, 1998 to March 1, 2008, still in follow-up 5 years post-diagnosis, and living survivors currently 19.1 ± 6.2 years old were diagnosed at a mean age of 9.1 ± 5.8 years with leukemias/lymphomas (47.2 %), central nervous system tumors (16.4 %), sarcomas (11.2 %), thyroid cancers or melanomas (7.8 %), and other solid tumors (17.4 %). The 10-year post-diagnosis clinic attendance probability was 27.8 % (SE = 2.3) overall, and 36.9 % (SE = 4.4) and 40.8 % (SE = 3.8), in patients with radiation and anthracycline exposure, respectively. In adjusted analysis, patients with insurance (HR = 2.90; p cancer survivors in our population-based sample had not attended survivorship clinic, even among those with high-risk exposures. Health care access, as measured by insurance status, was an important predictor of clinic attendance. More research is needed to clarify the link between insurance status and survivorship care to increase appropriate late effects surveillance in this population.

  3. Prevalence and nature of anaemia in a prospective, population-based sample of people with diabetes: Teesside anaemia in diabetes (TAD) study.

    Science.gov (United States)

    Jones, S C; Smith, D; Nag, S; Bilous, M T; Winship, S; Wood, A; Bilous, R W

    2010-06-01

    Anaemia occurs in 25% of people attending hospital diabetes clinics, but this may not be representative of all people with diabetes. We aimed to determine the prevalence of anaemia in a prospective population-based sample stratified by estimated glomerular filtration rate (eGFR) using the 4-point Modification of Diet in Renal Disease (MDRD) formula. All 7331 patients on our district register were stratified by eGFR. Seven hundred and thirty were approached by letter on two occasions. Two hundred and thirty-four (32%) returned questionnaires and blood samples. Responders (R), non-responders (NR) and the whole cohort (C) were similar: mean +/- sd age R 61.7 +/- 12.7 years; NR 61.3 +/- 15.1 years; C 61.8 +/- 14.2 years; diabetes duration R 8.8 +/- 8.6 years; NR 8.2 +/- 7.9 years; C 7.5 +/- 7.8 years, Type 1 diabetes R 10.1%, NR 10.8%, C 9.4%. Anaemia was defined using World Health Organization criteria: haemoglobin 60 ml/min per 1.73 m(2). Anaemia was as a result of erythropoietin deficiency in 34%, abnormal haematinics in 40% and was unexplained in 26% of patients. Five per cent of the patients had anaemia below the treatment threshold of 11 g/dl. The prevalence of unrecognized anaemia in population-based cohorts is lower than that in hospital-based studies. Current clinical surveillance in the UK is failing to detect anaemia in stage 3-5 chronic kidney disease (eGFR 60 ml/min per 1.73 m(2).

  4. Prevalence and Correlates of Suicidal Ideation Among Transgender Youth in California: Findings From a Representative, Population-Based Sample of High School Students.

    Science.gov (United States)

    Perez-Brumer, Amaya; Day, Jack K; Russell, Stephen T; Hatzenbuehler, Mark L

    2017-09-01

    No representative population-based studies of youth in the United States exist on gender identity-related disparities in suicidal ideation or on factors that underlie this disparity. To address this, this study examined gender identity-related disparities in the prevalence of suicidal ideation; evaluated whether established psychosocial factors explained these disparities; and identified correlates of suicidal ideation among all youth and stratified by gender identity. Data were derived from the 2013 to 2015 California Healthy Kids Survey (CHKS; N = 621,189) and a weighted subsample representative of the Californian student population (Biennial Statewide California Student Survey [CSS], N = 28,856). Prevalence of past 12-month self-reported suicidal ideation was nearly twice as high for transgender compared with non-transgender youth (33.73% versus 18.85%; χ 2  = 35.48, p suicidal ideation compared with non-transgender youth. Among transgender youth, only depressive symptoms (adjusted odds ratio 5.44, 95% CI 1.81-16.38) and victimization (adjusted odds ratio 2.66, 95% CI 1.26-5.65) remained significantly associated with higher odds of suicidal ideation in fully adjusted models. In multiple mediation analyses, depression attenuated the association between gender identity and suicidal ideation by 17.95% and victimization by 14.71%. This study uses the first representative population-based sample of youth in the United States that includes a measurement of gender identity to report on gender identity-related disparities in suicidal ideation and to identify potential mechanisms underlying this disparity in a representative sample. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  5. DSM-IV-TR and DSM-5 eating disorders in adolescents: prevalence, stability, and psychosocial correlates in a population-based sample of male and female adolescents.

    Science.gov (United States)

    Allen, Karina L; Byrne, Susan M; Oddy, Wendy H; Crosby, Ross D

    2013-08-01

    The current study aimed to compare the prevalence, stability, and psychosocial correlates of DSM-IV-TR and DSM-5 eating disorders, in a population-based sample of male and female adolescents followed prospectively from 14 to 20 years of age. Participants (N = 1,383; 49% male) were drawn from the Western Australian Pregnancy Cohort (Raine) Study, a prospective, population-based cohort study that has followed participants from prebirth to young adulthood. Detailed self-report questionnaires were used to assess eating disorder symptoms when participants were aged 14, 17, and 20 years. Comparisons between DSM-IV-TR and DSM-5 were conducted using McNemar chi-square tests and Fisher's exact tests. Changes in eating disorder prevalence over time were considered using generalized estimating equations. Eating disorder prevalence rates were significantly greater when using DSM-5 than DSM-IV-TR criteria, at all time points for females and at age 17 only for males. "Unspecified"/"other" eating disorder diagnoses were significantly less common when applying DSM-5 than DSM-IV-TR criteria, but still formed 15% to 30% of the DSM-5 cases. Diagnostic stability was low for all disorders, and DSM-5 binge eating disorder or purging disorder in early adolescence predicted DSM-5 bulimia nervosa in later adolescence. Cross-over from binge eating disorder to bulimia nervosa was particularly high. Regardless of the diagnostic classification system used, all eating disorder diagnoses were associated with depressive symptoms and poor mental health quality of life. These results provide further support for the clinical utility of DSM-5 eating disorder criteria, and for the significance of binge eating disorder and purging disorder. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  6. Screening for type 2 diabetes in a high-risk population: study design and feasibility of a population-based randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Klijs Bart

    2012-08-01

    Full Text Available Abstract Background We describe the design and present the results of the first year of a population-based study of screening for type 2 diabetes in individuals at high risk of developing the disease. High risk is defined as having abdominal obesity. Methods Between 2006 and 2007, 79,142 inhabitants of two Dutch municipalities aged 40–74 years were approached to participate in screening. Eligible participants had a self-reported waist circumference of ≥80 cm for women and ≥94 cm for men, and no known pre-existing diabetes. Of the respondents (n = 20,578; response rate 26%, 16,135 were abdominally obese. In total, 10,609 individuals gave written informed consent for participation and were randomized into either the screening (n = 5305 or the control arm (n = 5304. Participants in the screening arm were invited to have their fasting plasma glucose (FPG measured and were referred to their general practitioner (GP if it was ≥6.1 mmol/L. In addition, blood lipids were determined in the screening arm, because abdominal obesity is often associated with cardiovascular risk factors. Participants in both arms received written healthy lifestyle information. Between-group differences were analyzed with Chi-square tests and logistic regression (categorical variables and unpaired t-tests (continuous variables. Results The screening attendance rate was 84.1%. Attending screening was associated with age at randomization (OR = 1.03, 95% CI 1.02-1.04, being married (OR = 1.57, 95% CI 1.33-1.83 and not-smoking currently (OR = 0.52, 95% CI 0.44-0.62. Of the individuals screened, 5.6% had hyperglycemia, and a further 11.6% had an estimated absolute cardiovascular disease risk of 5% or higher, according to the Systematic Coronary Risk Evaluation risk model. These participants were referred to their GP. Conclusions Self-reported home-assessed waist circumference could feasibly detect persons at high risk of hyperglycemia or

  7. Remote population-based intervention for disruptive behavior at age four: study protocol for a randomized trial of Internet-assisted parent training (Strongest Families Finland-Canada).

    Science.gov (United States)

    McGrath, Patrick J; Sourander, Andre; Lingley-Pottie, Patricia; Ristkari, Terja; Cunningham, Charles; Huttunen, Jukka; Filbert, Katharine; Aromaa, Minna; Corkum, Penny; Hinkka-Yli-Salomäki, Susanna; Kinnunen, Malin; Lampi, Katja; Penttinen, Anne; Sinokki, Atte; Unruh, Anita; Vuorio, Jenni; Watters, Carolyn

    2013-10-21

    Oppositional Defiant Disorder (ODD) is characterized by angry and noncompliant behaviour. It is the most common disruptive behaviour disorder (DBD), with prevalence estimates of 6-9% for preschoolers and is closely linked to several long-term difficulties, including disorders of conduct, mood, anxiety, impulse-control, and substance abuse. ODD in children is related to parental depression, family dysfunction, and impairments in parental work performance. Children displaying early DBDs exhibit more symptoms of greater severity, more frequent offences, and commit more serious crimes later in life. The goal of the Strongest Families Finland Canada (SFFC) Smart Website intervention research program is to develop and evaluate an affordable, accessible, effective secondary prevention parent training program for disruptive behaviour in preschoolers to prevent the negative sequelae of ODD. Strongest Families is an 11-session program with two booster sessions that focuses on teaching skills to: strengthen parent-child relationships; reinforce positive behaviour; reduce conflict; manage daily transitions; plan for potentially problematic situations; promote emotional regulation and pro-social behaviour and decrease antisocial behaviour. This protocol paper describes an ongoing population-based randomized controlled trial (RCT) of high-risk 4 year-olds attending well-child clinics in Turku, Finland and environs to examine the effectiveness of the Strongest Families Smart Website intervention compared to an Education Control condition. Randomization consists of a 1:1 ratio for intervention versus the education group, stratified by the child's sex. The participants randomized to the intervention group receive access to the Strongest Families Smart Website and weekly telephone coaching sessions. The participants randomized to the Education Control condition receive access to a static website with parenting tips. Children are followed using parental and daycare teacher measures

  8. Triceps and Subscapular Skinfold Thickness Percentiles and Cut-Offs for Overweight and Obesity in a Population-Based Sample of Schoolchildren and Adolescents in Bogota, Colombia

    Directory of Open Access Journals (Sweden)

    Robinson Ramírez-Vélez

    2016-09-01

    Full Text Available The assessment of skinfold thickness is an objective measure of adiposity. The aims of this study were to establish Colombian smoothed centile charts and LMS L (Box–Cox transformation, M (median, and S (coefficient of variation tables for triceps, subscapular, and triceps + subscapular skinfolds; appropriate cut-offs were selected using receiver operating characteristic (ROC analysis based on a population-based sample of children and adolescents in Bogotá, Colombia. A cross-sectional study was conducted in 9618 children and adolescents (55.7% girls; age range of 9–17.9 years. Triceps and subscapular skinfold measurements were obtained using standardized methods. We calculated the triceps + subscapular skinfold (T + SS sum. Smoothed percentile curves for triceps and subscapular skinfold thickness were derived using the LMS method. ROC curve analyses were used to evaluate the optimal cut-off point of skinfold thickness for overweight and obesity, based on the International Obesity Task Force definitions. Subscapular and triceps skinfolds and T + SS were significantly higher in girls than in boys (p < 0.001. The ROC analysis showed that subscapular and triceps skinfolds and T + SS have a high discriminatory power in the identification of overweight and obesity in the sample population in this study. Our results provide sex- and age-specific normative reference standards for skinfold thickness values from a population from Bogotá, Colombia.

  9. A randomized controlled open trial of population-based disease and case management in a Medicare Plus Choice health maintenance organization.

    Science.gov (United States)

    Martin, David C; Berger, Marc L; Anstatt, David T; Wofford, Jonathan; Warfel, DeAnn; Turpin, Robin S; Cannuscio, Carolyn C; Teutsch, Steven M; Mansheim, Bernard J

    2004-10-01

    The object of this study was to examine the effect of population-based disease management and case management on resource use, self-reported health status, and member satisfaction with and retention in a Medicare Plus Choice health maintenance organization (HMO). Study design consisted of a prospective, randomized controlled open trial of 18 months' duration. Participants were 8504 Medicare beneficiaries aged 65 and older who had been continuously enrolled for at least 12 months in a network model Medicare Plus Choice HMO serving a contiguous nine-county metropolitan area. Members were care managed with an expert clinical information system and frequent telephone contact. Main outcomes included self-reported health status measured by the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), resource use measured by admission rates and bed-days per thousand per year, member satisfaction, and costs measured by paid claims. More favorable outcomes occurred in the intervention group for satisfaction with the health plan (P management and case management led to improved self-reported satisfaction and social function but not to a global net decrease in resource use or improved member retention.

  10. General exposures to prescription medications by race/ethnicity in a population-based sample: results from the Boston Area Community Health Survey.

    Science.gov (United States)

    Hall, Susan A; Chiu, Gretchen R; Kaufman, David W; Kelly, Judith P; Link, Carol L; Kupelian, Varant; McKinlay, John B

    2010-04-01

    Few recent U.S. studies have examined population-based patterns in prescription drug use and even fewer have considered detailed patterns by race/ethnicity. In a representative community sample, our objectives were to determine the most commonly used prescription drug classes, and to describe their use by age, gender, and race/ethnicity. Cross-sectional epidemiologic study of 5503 (1767 black, 1877 Hispanic, 1859 white) community-dwelling participants aged 30-79 in the Boston Area Community Health (BACH) Survey (2002-2005). Using medication information collected from an in-home interview and medication inventory, the prevalence of use of a therapeutic class (95% confidence interval (95%CI)) in the past month was estimated by gender, age group, and race/ethnicity. Estimates were weighted inversely to the probability of sampling for generalizablity to Boston, MA. The therapeutic class containing selective serotonin reuptake inhibitor/serotonin norepinephrine reuptake inhibitor (SSRI/SNRI) antidepressants was most commonly used (14.6%), followed by statins (13.9%), beta-adrenergic blockers (10.6%), and angiotensin-converting enzyme (ACE) inhibitors (10.5%). Within all age groups and both genders, black participants were substantially less likely than white to use SSRI/SNRI antidepressants (e.g., black men: 6.0% [95%CI: 3.9-8.1%]; white men: 15.0% [95%CI: 10.2-19.4%]). Other race/ethnic differences were observed: for example, black women were significantly less likely than other groups to use benzodiazepines (e.g., black: 2.6% [95%CI: 1.2-3.9%]; Hispanic: 9.4% [95%CI: 5.8-13.0%]). Race/ethnic differences in use of prescription therapeutic classes were observed in our community sample. Examining therapeutic classes rather than individual drugs resulted in a different distribution of common exposures compared to other surveys.

  11. Triceps and Subscapular Skinfold Thickness Percentiles and Cut-Offs for Overweight and Obesity in a Population-Based Sample of Schoolchildren and Adolescents in Bogota, Colombia

    Science.gov (United States)

    Ramírez-Vélez, Robinson; López-Cifuentes, Mario Ferney; Correa-Bautista, Jorge Enrique; González-Ruíz, Katherine; González-Jiménez, Emilio; Córdoba-Rodríguez, Diana Paola; Vivas, Andrés; Triana-Reina, Hector Reynaldo; Schmidt-RioValle, Jacqueline

    2016-01-01

    The assessment of skinfold thickness is an objective measure of adiposity. The aims of this study were to establish Colombian smoothed centile charts and LMS L (Box–Cox transformation), M (median), and S (coefficient of variation) tables for triceps, subscapular, and triceps + subscapular skinfolds; appropriate cut-offs were selected using receiver operating characteristic (ROC) analysis based on a population-based sample of children and adolescents in Bogotá, Colombia. A cross-sectional study was conducted in 9618 children and adolescents (55.7% girls; age range of 9–17.9 years). Triceps and subscapular skinfold measurements were obtained using standardized methods. We calculated the triceps + subscapular skinfold (T + SS) sum. Smoothed percentile curves for triceps and subscapular skinfold thickness were derived using the LMS method. ROC curve analyses were used to evaluate the optimal cut-off point of skinfold thickness for overweight and obesity, based on the International Obesity Task Force definitions. Subscapular and triceps skinfolds and T + SS were significantly higher in girls than in boys (p Colombia. PMID:27669294

  12. Lesbian, gay, bisexual, and transgender hate crimes and suicidality among a population-based sample of sexual-minority adolescents in Boston.

    Science.gov (United States)

    Duncan, Dustin T; Hatzenbuehler, Mark L

    2014-02-01

    We examined whether past-year suicidality among sexual-minority adolescents was more common in neighborhoods with a higher prevalence of hate crimes targeting lesbian, gay, bisexual, and transgender (LGBT) individuals. Participants' data came from a racially/ethnically diverse population-based sample of 9th- through 12th-grade public school students in Boston, Massachusetts (n = 1292). Of these, 108 (8.36%) reported a minority sexual orientation. We obtained data on LGBT hate crimes involving assaults or assaults with battery between 2005 and 2008 from the Boston Police Department and linked the data to the adolescent's residential address. Sexual-minority youths residing in neighborhoods with higher rates of LGBT assault hate crimes were significantly more likely to report suicidal ideation (P = .013) and suicide attempts (P = .006), than were those residing in neighborhoods with lower LGBT assault hate crime rates. We observed no relationships between overall neighborhood-level violent and property crimes and suicidality among sexual-minority adolescents (P > .05), providing evidence for specificity of the results to LGBT assault hate crimes. Neighborhood context (i.e., LGBT hate crimes) may contribute to sexual-orientation disparities in adolescent suicidality, highlighting potential targets for community-level suicide-prevention programs.

  13. Triceps and Subscapular Skinfold Thickness Percentiles and Cut-Offs for Overweight and Obesity in a Population-Based Sample of Schoolchildren and Adolescents in Bogota, Colombia.

    Science.gov (United States)

    Ramírez-Vélez, Robinson; López-Cifuentes, Mario Ferney; Correa-Bautista, Jorge Enrique; González-Ruíz, Katherine; González-Jiménez, Emilio; Córdoba-Rodríguez, Diana Paola; Vivas, Andrés; Triana-Reina, Hector Reynaldo; Schmidt-RioValle, Jacqueline

    2016-09-24

    The assessment of skinfold thickness is an objective measure of adiposity. The aims of this study were to establish Colombian smoothed centile charts and LMS L (Box-Cox transformation), M (median), and S (coefficient of variation) tables for triceps, subscapular, and triceps + subscapular skinfolds; appropriate cut-offs were selected using receiver operating characteristic (ROC) analysis based on a population-based sample of children and adolescents in Bogotá, Colombia. A cross-sectional study was conducted in 9618 children and adolescents (55.7% girls; age range of 9-17.9 years). Triceps and subscapular skinfold measurements were obtained using standardized methods. We calculated the triceps + subscapular skinfold (T + SS) sum. Smoothed percentile curves for triceps and subscapular skinfold thickness were derived using the LMS method. ROC curve analyses were used to evaluate the optimal cut-off point of skinfold thickness for overweight and obesity, based on the International Obesity Task Force definitions. Subscapular and triceps skinfolds and T + SS were significantly higher in girls than in boys (p Colombia.

  14. Let's Get Physical: Sexual Orientation Disparities in Physical Activity, Sports Involvement, and Obesity Among a Population-Based Sample of Adolescents.

    Science.gov (United States)

    Mereish, Ethan H; Poteat, V Paul

    2015-09-01

    We examined sexual orientation disparities in physical activity, sports involvement, and obesity among a population-based adolescent sample. We analyzed data from the 2012 Dane County Youth Assessment for 13,933 students in grades 9 through 12 in 22 Wisconsin high schools. We conducted logistic regressions to examine sexual orientation disparities in physical activity, sports involvement, and body mass index among male and female adolescents. When we accounted for several covariates, compared with heterosexual females, sexual minority females were less likely to participate in team sports (adjusted odds ratio [AOR] = 0.44; 95% confidence interval [CI] = 0.37, 0.53) and more likely to be overweight (AOR = 1.28; 95% CI = 1.02, 1.62) or obese (AOR = 1.88; 95% CI = 1.43, 2.48). Sexual minority males were less likely than heterosexual males to be physically active (AOR = 0.62; 95% CI = 0.46, 0.83) or to participate in team sports (AOR = 0.26; 95% CI = 0.20, 0.32), but the 2 groups did not differ in their risk of obesity. Sexual orientation health disparities in physical activity and obesity are evident during adolescence. Culturally affirming research, interventions, and policies are needed for sexual minority youths.

  15. Let’s Get Physical: Sexual Orientation Disparities in Physical Activity, Sports Involvement, and Obesity Among a Population-Based Sample of Adolescents

    Science.gov (United States)

    Poteat, V. Paul

    2015-01-01

    Objectives. We examined sexual orientation disparities in physical activity, sports involvement, and obesity among a population-based adolescent sample. Methods. We analyzed data from the 2012 Dane County Youth Assessment for 13 933 students in grades 9 through 12 in 22 Wisconsin high schools. We conducted logistic regressions to examine sexual orientation disparities in physical activity, sports involvement, and body mass index among male and female adolescents. Results. When we accounted for several covariates, compared with heterosexual females, sexual minority females were less likely to participate in team sports (adjusted odds ratio [AOR] = 0.44; 95% confidence interval [CI] = 0.37, 0.53) and more likely to be overweight (AOR = 1.28; 95% CI = 1.02, 1.62) or obese (AOR = 1.88; 95% CI = 1.43, 2.48). Sexual minority males were less likely than heterosexual males to be physically active (AOR = 0.62; 95% CI = 0.46, 0.83) or to participate in team sports (AOR = 0.26; 95% CI = 0.20, 0.32), but the 2 groups did not differ in their risk of obesity. Conclusions. Sexual orientation health disparities in physical activity and obesity are evident during adolescence. Culturally affirming research, interventions, and policies are needed for sexual minority youths. PMID:26180946

  16. Visual acuity and the causes of visual loss in a population-based sample of 6-year-old Australian children.

    Science.gov (United States)

    Robaei, Dana; Rose, Kathryn; Ojaimi, Elvis; Kifley, Annette; Huynh, Son; Mitchell, Paul

    2005-07-01

    To describe the distribution of visual acuity and causes of visual loss in a representative sample of Australian schoolchildren. Population-based cross-sectional study. One thousand seven hundred thirty-eight predominantly 6-year old children examined during 2003 to 2004. Logarithm of the minimum angle of resolution (logMAR) visual acuity was measured in both eyes before and after pinhole correction and with spectacles if worn. Cycloplegic autorefraction (cyclopentolate) and detailed dilated fundus examination were performed. Visual impairment was defined as any (visual acuity or =+2.0 D, deemed significant when > or =+3.0 D. Astigmatism was defined as cylinder > or =1.0 D and anisometropia as SE refraction difference between eyes at least 1.0 D. Amblyopia was defined as corrected visual acuity glasses if worn) was found in the better and worse eyes of 15 children (0.9%) and 54 children (2.8%), respectively. This was mainly due to under corrected or uncorrected refractive error. This study has documented a relatively low prevalence of visual impairment in a population of Australian children. Uncorrected astigmatism and amblyopia were the most frequent causes.

  17. Prevalence of DSM-IV disorders in a population-based sample of 5- to 8-year-old children: the impact of impairment criteria.

    Science.gov (United States)

    Rijlaarsdam, Jolien; Stevens, Gonneke W J M; van der Ende, Jan; Hofman, Albert; Jaddoe, Vincent W V; Verhulst, Frank C; Tiemeier, Henning

    2015-11-01

    This study determined the impact of impairment criteria on the prevalence and patterns of comorbidity of child DSM-IV disorders. The validity of these impairment criteria was tested against different measures of mental health care referral and utilization. We interviewed parents of 1,154 children aged 5-8 years in-depth using the Diagnostic Interview Schedule for Children in Rotterdam, the Netherlands, to establish DSM-IV diagnosis. These children were randomly selected or oversampled based on Child Behavior Checklist ratings from a large population-based study (N = 6,172). Referral data were extracted from the psychiatric interview as well as from a follow-up questionnaire. The results showed an overall prevalence of DSM-IV disorders of 31.1 % when impairment was not considered. This rate declined to 22.9 % when mild impairment was required and declined even further, to 10.3 %, for more severe levels of impairment. Similarly, the overall comorbidity rate declined from 8.5 to 6.7 and 2.7 % when mild and severe impairment were required, respectively. Virtually all children who attained symptom thresholds for a specific disorder, and had been referred to a mental health care professional because of the associated symptoms, also had mild impairment. The requirement of severe impairment criteria significantly increased diagnostic thresholds, but for most disorders, this definition captured only half of the clinically referred cases. In conclusion, prevalence was highly dependent upon the criteria used to define impairment. If severe impairment is made a diagnostic requirement, many children with psychiatric symptoms and mild impairment seeking mental health care will be undiagnosed and possibly untreated.

  18. A random spatial sampling method in a rural developing nation

    Science.gov (United States)

    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...

  19. Reduced memory and attention performance in a population-based sample of young adults with a moderate lifetime use of cannabis, ecstasy and alcohol.

    Science.gov (United States)

    Indlekofer, F; Piechatzek, M; Daamen, M; Glasmacher, C; Lieb, R; Pfister, H; Tucha, O; Lange, K W; Wittchen, H U; Schütz, C G

    2009-07-01

    reaction time was found. The results are consistent with decrements of memory and attentional performance described in previous studies. These effects are relatively small; however, it must be kept in mind that this study focussed on assessing young adults with moderate drug use from a population-based study.

  20. Effectiveness of a two-step population-based osteoporosis screening program using FRAX: the randomized Risk-stratified Osteoporosis Strategy Evaluation (ROSE) study.

    Science.gov (United States)

    Rubin, K H; Rothmann, M J; Holmberg, T; Høiberg, M; Möller, S; Barkmann, R; Glüer, C C; Hermann, A P; Bech, M; Gram, J; Brixen, K

    2017-12-07

    The Risk-stratified Osteoporosis Strategy Evaluation (ROSE) study investigated the effectiveness of a two-step screening program for osteoporosis in women. We found no overall reduction in fractures from systematic screening compared to the current case-finding strategy. The group of moderate- to high-risk women, who accepted the invitation to DXA, seemed to benefit from the program. The purpose of the ROSE study was to investigate the effectiveness of a two-step population-based osteoporosis screening program using the Fracture Risk Assessment Tool (FRAX) derived from a self-administered questionnaire to select women for DXA scan. After the scanning, standard osteoporosis management according to Danish national guidelines was followed. Participants were randomized to either screening or control group, and randomization was stratified according to age and area of residence. Inclusion took place from February 2010 to November 2011. Participants received a self-administered questionnaire, and women in the screening group with a FRAX score ≥ 15% (major osteoporotic fractures) were invited to a DXA scan. Primary outcome was incident clinical fractures. Intention-to-treat analysis and two per-protocol analyses were performed. A total of 3416 fractures were observed during a median follow-up of 5 years. No significant differences were found in the intention-to-treat analyses with 34,229 women included aged 65-80 years. The per-protocol analyses showed a risk reduction in the group that underwent DXA scanning compared to women in the control group with a FRAX ≥ 15%, in regard to major osteoporotic fractures, hip fractures, and all fractures. The risk reduction was most pronounced for hip fractures (adjusted SHR 0.741, p = 0.007). Compared to an office-based case-finding strategy, the two-step systematic screening strategy had no overall effect on fracture incidence. The two-step strategy seemed, however, to be beneficial in the group of women who were

  1. Normative reference values for the 20 m shuttle-run test in a population-based sample of school-aged youth in Bogota, Colombia: the FUPRECOL study.

    Science.gov (United States)

    Ramírez-Vélez, Robinson; Palacios-López, Adalberto; Humberto Prieto-Benavides, Daniel; Enrique Correa-Bautista, Jorge; Izquierdo, Mikel; Alonso-Martínez, Alicia; Lobelo, Felipe

    2017-01-01

    Our aim was to determine the normative reference values of cardiorespiratory fitness (CRF) and to establish the proportion of subjects with low CRF suggestive of future cardio-metabolic risk. A total of 7244 children and adolescents attending public schools in Bogota, Colombia (55.7% girls; age range of 9-17.9 years) participated in this study. We expressed CRF performance as the nearest stage (minute) completed and the estimated peak oxygen consumption (V˙O2peak ). Smoothed percentile curves were calculated. In addition, we present the prevalence of low CRF after applying a correction factor to account for the impact of Bogota's altitude (2625 m over sea level) on CRF assessment, and we calculated the number of participants who fell below health-related FITNESSGRAM cut-points for low CRF. Shuttles and V˙O2peak were higher in boys than in girls in all age groups. In boys, there were higher levels of performance with increasing age, with most gains between the ages of 13 and 17. The proportion of subjects with a low CRF, suggestive of future cardio-metabolic risk (health risk FITNESSGRAM category) was 31.5% (28.2% for boys and 34.1% for girls; X2 P = .001). After applying a 1.11 altitude correction factor, the overall prevalence of low CRF was 11.5% (9.6% for boys and 13.1% for girls; X2 P = .001). Our results provide sex- and age-specific normative reference standards for the 20 m shuttle-run test and estimated V˙O2peak values in a large, population-based sample of schoolchildren from a large Latin-American city at high altitude. © 2016 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc.

  2. Patterns and predictors of sitting time over ten years in a large population-based Canadian sample: Findings from the Canadian Multicentre Osteoporosis Study (CaMos

    Directory of Open Access Journals (Sweden)

    Klaus Gebel

    2017-03-01

    Full Text Available Our objective was to describe patterns and predictors of sedentary behavior (sitting time over 10 years among a large Canadian cohort. Data are from the Canadian Multicentre Osteoporosis Study, a prospective study of women and men randomly selected from the general population. Respondents reported socio-demographics, lifestyle behaviors and health outcomes in interviewer-administered questionnaires; weight and height were measured. Baseline data were collected between 1995 and 1997 (n = 9418; participation rate = 42%, and at 5- (n = 7648 and 10-year follow-ups (n = 5567. Total sitting time was summed across domain-specific questions at three time points and dichotomized into “low” (≤7 h/day and “high” (>7 h/day, based on recent meta-analytic evidence on time sitting and all-cause mortality. Ten-year sitting patterns were classified as “consistently high”, “consistently low”, “increased”, “decreased”, and “mixed”. Predictors of sedentary behavior patterns were explored using chi-square tests, ANOVA and logistic regression. At baseline (mean age = 62.1 years ± 13.4 average sitting was 6.9 h/day; it was 7.0 at 5- and 10-year follow-ups (p for trend = 0.12. Overall 23% reported consistently high sitting time, 22% consistently low sitting, 14% decreased sitting, 17% increased sitting with 24% mixed patterns. Consistently high sitters were more likely to be men, university educated, full-time employed, obese, and to report consistently low physical activity levels. This is one of the first population-based studies to explore patterns of sedentary behavior (multi-domain sitting within men and women over years. Risk classification of sitting among many adults changed during follow-up. Thus, studies of sitting and health would benefit from multiple measures of sitting over time.

  3. Power Spectrum Estimation of Randomly Sampled Signals

    DEFF Research Database (Denmark)

    Velte, Clara M.; Buchhave, Preben; K. George, William

    2014-01-01

    with high data rate and low inherent bias, respectively, while residence time weighting provides non-biased estimates regardless of setting. The free-running processor was also tested and compared to residence time weighting using actual LDA measurements in a turbulent round jet. Power spectra from...... of alternative methods attempting to produce correct power spectra have been invented andtested. The objective of the current study is to create a simple computer generated signal for baseline testing of residence time weighting and some of the most commonly proposed algorithms (or algorithms which most...... modernalgorithms ultimately are based on), sample-and-hold and the direct spectral estimator without residence time weighting, and compare how they perform in relation to power spectra based on the equidistantly sampled reference signal. The computer generated signal is a Poisson process with a sample rate...

  4. Random constraint sampling and duality for convex optimization

    OpenAIRE

    Haskell, William B.; Pengqian, Yu

    2016-01-01

    We are interested in solving convex optimization problems with large numbers of constraints. Randomized algorithms, such as random constraint sampling, have been very successful in giving nearly optimal solutions to such problems. In this paper, we combine random constraint sampling with the classical primal-dual algorithm for convex optimization problems with large numbers of constraints, and we give a convergence rate analysis. We then report numerical experiments that verify the effectiven...

  5. Hemodynamic and glucometabolic factors fail to predict renal function in a random population sample

    DEFF Research Database (Denmark)

    Pareek, M.; Nielsen, M.; Olesen, Thomas Bastholm

    2015-01-01

    Objective: To determine whether baseline hemodynamic and/or glucometabolic risk factors could predict renal function at follow-up, independently of baseline serum creatinine, in survivors from a random population sample. Design and method: We examined associations between baseline serum creatinine...... indices of beta-cell function (HOMA-2B), insulin sensitivity (HOMA-2S), and insulin resistance (HOMA-2IR)), traditional cardiovascular risk factors (age, sex, smoking status, body mass index, diabetes mellitus, total serum cholesterol), and later renal function determined as serum cystatin C in 238 men...... and 7 women aged 38 to 49 years at the time of inclusion, using multivariable linear regression analysis (p-entry 0.05, p-removal 0.20). Study subjects came from a random population based sample and were included 1974-1992, whilst the follow-up with cystatin C measurement was performed 2002...

  6. Random number datasets generated from statistical analysis of randomly sampled GSM recharge cards.

    Science.gov (United States)

    Okagbue, Hilary I; Opanuga, Abiodun A; Oguntunde, Pelumi E; Ugwoke, Paulinus O

    2017-02-01

    In this article, a random number of datasets was generated from random samples of used GSM (Global Systems for Mobile Communications) recharge cards. Statistical analyses were performed to refine the raw data to random number datasets arranged in table. A detailed description of the method and relevant tests of randomness were also discussed.

  7. Power Spectrum Estimation of Randomly Sampled Signals

    DEFF Research Database (Denmark)

    Velte, C. M.; Buchhave, P.; K. George, W.

    . Residence time weighting provides non-biased estimates regardless of setting. The free-running processor was also tested and compared to residence time weighting using actual LDA measurements in a turbulent round jet. Power spectra from measurements on the jet centerline and the outer part of the jet...... sine waves. The primary signal and the corresponding power spectrum are shown in Figure 1. The conventional spectrum shows multiple erroneous mixing frequencies and the peak values are too low. The residence time weighted spectrum is correct. The sample-and-hold spectrum has lower power than...... the correct spectrum, and the f -2-filtering effect appearing for low data densities is evident (Adrian and Yao 1987). The remaining tests also show that sample-and-hold and the free-running processor perform well only under very particular circumstances with high data rate and low inherent bias, respectively...

  8. Linkage and association studies identify a novel locus for Alzheimer disease at 7q36 in a Dutch population-based sample

    NARCIS (Netherlands)

    P. de Rijk (Peter); M. Cruts (Marc); K. Sleegers (Kristel); B. Dermaut (Bart); J. Theuns (Jessie); S. Weckx; C.M. van Duijn (Cornelia); T. Pooter; E. Corsmit; J. Del-Favero (Jurgen); J.C. van Swieten (John); Y.S. Aulchenko (Yurii); R. Rademakers (Rosa); M. van den Broeck (Marleen); C. van Broeckhoven (Christine)

    2005-01-01

    textabstractWe obtained conclusive linkage of Alzheimer disease (AD) with a candidate region of 19.7 cM at 7q36 in an extended multiplex family, family 1270, ascertained in a population-based study of early-onset AD in the northern Netherlands. Single-nucleotide polymorphism and haplotype

  9. Are most samples of animals systematically biased? Consistent individual trait differences bias samples despite random sampling.

    Science.gov (United States)

    Biro, Peter A

    2013-02-01

    Sampling animals from the wild for study is something nearly every biologist has done, but despite our best efforts to obtain random samples of animals, 'hidden' trait biases may still exist. For example, consistent behavioral traits can affect trappability/catchability, independent of obvious factors such as size and gender, and these traits are often correlated with other repeatable physiological and/or life history traits. If so, systematic sampling bias may exist for any of these traits. The extent to which this is a problem, of course, depends on the magnitude of bias, which is presently unknown because the underlying trait distributions in populations are usually unknown, or unknowable. Indeed, our present knowledge about sampling bias comes from samples (not complete population censuses), which can possess bias to begin with. I had the unique opportunity to create naturalized populations of fish by seeding each of four small fishless lakes with equal densities of slow-, intermediate-, and fast-growing fish. Using sampling methods that are not size-selective, I observed that fast-growing fish were up to two-times more likely to be sampled than slower-growing fish. This indicates substantial and systematic bias with respect to an important life history trait (growth rate). If correlations between behavioral, physiological and life-history traits are as widespread as the literature suggests, then many animal samples may be systematically biased with respect to these traits (e.g., when collecting animals for laboratory use), and affect our inferences about population structure and abundance. I conclude with a discussion on ways to minimize sampling bias for particular physiological/behavioral/life-history types within animal populations.

  10. Genetic variation in the CYP1A1 gene is related to circulating PCB118 levels in a population-based sample

    Energy Technology Data Exchange (ETDEWEB)

    Lind, Lars [Department of Medical Sciences, Cardiovascular Epidemiology, Uppsala University, Uppsala (Sweden); Penell, Johanna [Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala (Sweden); Syvänen, Anne-Christine; Axelsson, Tomas [Department of Medical Sciences, Molecular Medicine and Science for Life Laboratory, Uppsala University, Uppsala (Sweden); Ingelsson, Erik [Department of Medical Sciences, Molecular Epidemiology and Science for Life Laboratory, Uppsala University, Uppsala (Sweden); Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford (United Kingdom); Morris, Andrew P.; Lindgren, Cecilia [Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford (United Kingdom); Salihovic, Samira; Bavel, Bert van [MTM Research Centre, School of Science and Technology, Örebro University, Örebro (Sweden); Lind, P. Monica, E-mail: monica.lind@medsci.uu.se [Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala (Sweden)

    2014-08-15

    Several of the polychlorinated biphenyls (PCBs), i.e. the dioxin-like PCBs, are known to induce the P450 enzymes CYP1A1, CYP1A2 and CYP1B1 by activating the aryl hydrocarbon receptor (Ah)-receptor. We evaluated if circulating levels of PCBs in a population sample were related to genetic variation in the genes encoding these CYPs. In the population-based Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study (1016 subjects all aged 70), 21 SNPs in the CYP1A1, CYP1A2 and CYP1B1 genes were genotyped. Sixteen PCB congeners were analysed by high-resolution chromatography coupled to high-resolution mass spectrometry (HRGC/ HRMS). Of the investigated relationships between SNPs in the CYP1A1, CYP1A2 and CYP1B1 and six PCBs (congeners 118, 126, 156, 169, 170 and 206) that captures >80% of the variation of all PCBs measured, only the relationship between CYP1A1 rs2470893 was significantly related to PCB118 levels following strict adjustment for multiple testing (p=0.00011). However, there were several additional SNPs in the CYP1A2 and CYP1B1 that showed nominally significant associations with PCB118 levels (p-values in the 0.003–0.05 range). Further, several SNPs in the CYP1B1 gene were related to both PCB156 and PCB206 with p-values in the 0.005–0.05 range. Very few associations with p<0.05 were seen for PCB126, PCB169 or PCB170. Genetic variation in the CYP1A1 was related to circulating PCB118 levels in the general elderly population. Genetic variation in CYP1A2 and CYP1B1 might also be associated with other PCBs. - Highlights: • We studied the relationship between PCBs and the genetic variation in the CYP genes. • Cross sectional data from a cohort of elderly were analysed. • The PCB levels were evaluated versus 21 SNPs in three CYP genes. • PCB 118 was related to variation in the CYP1A1 gene.

  11. ADHD symptoms across the lifespan: a comparison of symptoms captured by the Wender and Barkley Scales and DSM-IV criteria in a population-based Swedish sample aged 65 to 80.

    Science.gov (United States)

    Guldberg-Kjär, Taina; Johansson, Boo

    2015-05-01

    The aim was to compare different scales capturing ADHD symptoms for older individuals' self-reports about childhood and current ADHD symptomatology. An additional aim was relating these results to the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) ADHD criteria. The 25-item Wender Utah Rating Scale (WURS) administered in a population-based sample of 1,599 individuals aged 65 to 80. Two subsamples each with 30 individuals were randomly drawn based on their Wender Utah Rating Scale (WURS) scores, and studied using the Wender Riktad ADHD Symtom Skala (WRASS), interview assessed Barkley Scales, and DSM-IV ADHD criteria. Higher WURS and WRASS scores were related to higher Barkley Childhood and Current Symptoms Scales Scores. Also, reporting more symptoms on these scales was related to meeting DSM-IV criteria for childhood and current ADHD. The results support significant persistence of ADHD symptoms when using different scales designed for the capture of childhood and current ADHD symptomatology. Further studies of ADHD in a lifespan perspective are encouraged. © 2013 SAGE Publications.

  12. Objectively assessed physical activity and aerobic fitness in a population-based sample of Norwegian 9- and 15-year-olds

    DEFF Research Database (Denmark)

    Kolle, E; Steene-Johannessen, J; Andersen, Lars Bo

    2010-01-01

    The present study described current physical activity, determined compliance with physical activity guidelines and assessed aerobic fitness in a nationally representative sample of 9- and 15-year-olds in Norway. In 2005-2006, 2299 children and adolescents were randomly recruited. The participation...... more active than 15-year-olds. Physical activity was higher during weekdays than weekends, and 9-year-olds were most active during spring. While four out of five children met current physical activity guidelines, only half of the adolescents did. The mean (SD) values for peak VO2 were: 9-year-old boys....... Finally, girls and adolescents seem appropriate targets when promoting physical activity in order to increase the proportion meeting the recommendations....

  13. SOME SYSTEMATIC SAMPLING STRATEGIES USING MULTIPLE RANDOM STARTS

    Directory of Open Access Journals (Sweden)

    Sampath Sundaram

    2010-09-01

    Full Text Available In this paper an attempt is made to extend linear systematic sampling using multiple random starts due to Gautschi(1957for various types of systematic sampling schemes available in literature, namely(i  Balanced Systematic Sampling (BSS of  Sethi (1965 and (ii Modified Systematic Sampling (MSS of Singh, Jindal, and Garg  (1968. Further, the proposed methods were compared with Yates corrected estimator developed with reference to Gautschi’s Linear systematic sampling (LSS with two random starts using appropriate super population models with the  help of R package for statistical computing.

  14. Efficient sampling of complex network with modified random walk strategies

    Science.gov (United States)

    Xie, Yunya; Chang, Shuhua; Zhang, Zhipeng; Zhang, Mi; Yang, Lei

    2018-02-01

    We present two novel random walk strategies, choosing seed node (CSN) random walk and no-retracing (NR) random walk. Different from the classical random walk sampling, the CSN and NR strategies focus on the influences of the seed node choice and path overlap, respectively. Three random walk samplings are applied in the Erdös-Rényi (ER), Barabási-Albert (BA), Watts-Strogatz (WS), and the weighted USAir networks, respectively. Then, the major properties of sampled subnets, such as sampling efficiency, degree distributions, average degree and average clustering coefficient, are studied. The similar conclusions can be reached with these three random walk strategies. Firstly, the networks with small scales and simple structures are conducive to the sampling. Secondly, the average degree and the average clustering coefficient of the sampled subnet tend to the corresponding values of original networks with limited steps. And thirdly, all the degree distributions of the subnets are slightly biased to the high degree side. However, the NR strategy performs better for the average clustering coefficient of the subnet. In the real weighted USAir networks, some obvious characters like the larger clustering coefficient and the fluctuation of degree distribution are reproduced well by these random walk strategies.

  15. Spatial Random Sampling: A Structure-Preserving Data Sketching Tool

    Science.gov (United States)

    Rahmani, Mostafa; Atia, George K.

    2017-09-01

    Random column sampling is not guaranteed to yield data sketches that preserve the underlying structures of the data and may not sample sufficiently from less-populated data clusters. Also, adaptive sampling can often provide accurate low rank approximations, yet may fall short of producing descriptive data sketches, especially when the cluster centers are linearly dependent. Motivated by that, this paper introduces a novel randomized column sampling tool dubbed Spatial Random Sampling (SRS), in which data points are sampled based on their proximity to randomly sampled points on the unit sphere. The most compelling feature of SRS is that the corresponding probability of sampling from a given data cluster is proportional to the surface area the cluster occupies on the unit sphere, independently from the size of the cluster population. Although it is fully randomized, SRS is shown to provide descriptive and balanced data representations. The proposed idea addresses a pressing need in data science and holds potential to inspire many novel approaches for analysis of big data.

  16. Methods for sample size determination in cluster randomized trials.

    Science.gov (United States)

    Rutterford, Clare; Copas, Andrew; Eldridge, Sandra

    2015-06-01

    The use of cluster randomized trials (CRTs) is increasing, along with the variety in their design and analysis. The simplest approach for their sample size calculation is to calculate the sample size assuming individual randomization and inflate this by a design effect to account for randomization by cluster. The assumptions of a simple design effect may not always be met; alternative or more complicated approaches are required. We summarise a wide range of sample size methods available for cluster randomized trials. For those familiar with sample size calculations for individually randomized trials but with less experience in the clustered case, this manuscript provides formulae for a wide range of scenarios with associated explanation and recommendations. For those with more experience, comprehensive summaries are provided that allow quick identification of methods for a given design, outcome and analysis method. We present first those methods applicable to the simplest two-arm, parallel group, completely randomized design followed by methods that incorporate deviations from this design such as: variability in cluster sizes; attrition; non-compliance; or the inclusion of baseline covariates or repeated measures. The paper concludes with methods for alternative designs. There is a large amount of methodology available for sample size calculations in CRTs. This paper gives the most comprehensive description of published methodology for sample size calculation and provides an important resource for those designing these trials. © The Author 2015. Published by Oxford University Press on behalf of the International Epidemiological Association.

  17. SOME SYSTEMATIC SAMPLING STRATEGIES USING MULTIPLE RANDOM STARTS

    OpenAIRE

    Sampath Sundaram; Ammani Sivaraman

    2010-01-01

    In this paper an attempt is made to extend linear systematic sampling using multiple random starts due to Gautschi(1957)for various types of systematic sampling schemes available in literature, namely(i)  Balanced Systematic Sampling (BSS) of  Sethi (1965) and (ii) Modified Systematic Sampling (MSS) of Singh, Jindal, and Garg  (1968). Further, the proposed methods were compared with Yates corrected estimator developed with reference to Gautschi’s Linear systematic samplin...

  18. Sampling large random knots in a confined space

    Energy Technology Data Exchange (ETDEWEB)

    Arsuaga, J [Department of Mathematics, San Francisco State University, 1600 Holloway Ave, San Francisco, CA 94132 (United States); Blackstone, T [Department of Computer Science, San Francisco State University, 1600 Holloway Ave., San Francisco, CA 94132 (United States); Diao, Y [Department of Mathematics and Statistics, University of North Carolina at Charlotte, Charlotte, NC 28223 (United States); Hinson, K [Department of Mathematics and Statistics, University of North Carolina at Charlotte, Charlotte, NC 28223 (United States); Karadayi, E [Department of Mathematics, University of South Florida, 4202 E Fowler Avenue, Tampa, FL 33620 (United States); Saito, M [Department of Mathematics, University of South Florida, 4202 E Fowler Avenue, Tampa, FL 33620 (United States)

    2007-09-28

    DNA knots formed under extreme conditions of condensation, as in bacteriophage P4, are difficult to analyze experimentally and theoretically. In this paper, we propose to use the uniform random polygon model as a supplementary method to the existing methods for generating random knots in confinement. The uniform random polygon model allows us to sample knots with large crossing numbers and also to generate large diagrammatically prime knot diagrams. We show numerically that uniform random polygons sample knots with large minimum crossing numbers and certain complicated knot invariants (as those observed experimentally). We do this in terms of the knot determinants or colorings. Our numerical results suggest that the average determinant of a uniform random polygon of n vertices grows faster than O(e{sup n{sup 2}}). We also investigate the complexity of prime knot diagrams. We show rigorously that the probability that a randomly selected 2D uniform random polygon of n vertices is almost diagrammatically prime goes to 1 as n goes to infinity. Furthermore, the average number of crossings in such a diagram is at the order of O(n{sup 2}). Therefore, the two-dimensional uniform random polygons offer an effective way in sampling large (prime) knots, which can be useful in various applications.

  19. Sequential time interleaved random equivalent sampling for repetitive signal

    Science.gov (United States)

    Zhao, Yijiu; Liu, Jingjing

    2016-12-01

    Compressed sensing (CS) based sampling techniques exhibit many advantages over other existing approaches for sparse signal spectrum sensing; they are also incorporated into non-uniform sampling signal reconstruction to improve the efficiency, such as random equivalent sampling (RES). However, in CS based RES, only one sample of each acquisition is considered in the signal reconstruction stage, and it will result in more acquisition runs and longer sampling time. In this paper, a sampling sequence is taken in each RES acquisition run, and the corresponding block measurement matrix is constructed using a Whittaker-Shannon interpolation formula. All the block matrices are combined into an equivalent measurement matrix with respect to all sampling sequences. We implemented the proposed approach with a multi-cores analog-to-digital converter (ADC), whose ADC cores are time interleaved. A prototype realization of this proposed CS based sequential random equivalent sampling method has been developed. It is able to capture an analog waveform at an equivalent sampling rate of 40 GHz while sampled at 1 GHz physically. Experiments indicate that, for a sparse signal, the proposed CS based sequential random equivalent sampling exhibits high efficiency.

  20. Optimum allocation in multivariate stratified random sampling: Stochastic matrix optimisation

    OpenAIRE

    Diaz-Garcia, Jose A.; Ramos-Quiroga, Rogelio

    2011-01-01

    The allocation problem for multivariate stratified random sampling as a problem of stochastic matrix integer mathematical programming is considered. With these aims the asymptotic normality of sample covariance matrices for each strata is established. Some alternative approaches are suggested for its solution. An example is solved by applying the proposed techniques.

  1. Performance of Random Effects Model Estimators under Complex Sampling Designs

    Science.gov (United States)

    Jia, Yue; Stokes, Lynne; Harris, Ian; Wang, Yan

    2011-01-01

    In this article, we consider estimation of parameters of random effects models from samples collected via complex multistage designs. Incorporation of sampling weights is one way to reduce estimation bias due to unequal probabilities of selection. Several weighting methods have been proposed in the literature for estimating the parameters of…

  2. A random spatial sampling method in a rural developing nation.

    Science.gov (United States)

    Kondo, Michelle C; Bream, Kent D W; Barg, Frances K; Branas, Charles C

    2014-04-10

    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 using geographical information system (GIS) software and global positioning system (GPS) technology for application in a health survey in a rural region of Guatemala, as well as a qualitative study of the enumeration process. This method offers an alternative sampling technique that could reduce opportunities for bias in household selection compared to cluster methods. However, its use is subject to issues surrounding survey preparation, technological limitations and in-the-field household selection. Application of this method in remote areas will raise challenges surrounding the boundary delineation process, use and translation of satellite imagery between GIS and GPS, and household selection at each survey point in varying field conditions. This method favors household selection in denser urban areas and in new residential developments. Random spatial sampling methodology can be used to survey a random sample of population in a remote region of a developing nation. Although this method should be further validated and compared with more established methods to determine its utility in social survey applications, it shows promise for use in developing nations with resource-challenged environments where detailed geographic and human census data are less available.

  3. Sample Selection in Randomized Experiments: A New Method Using Propensity Score Stratified Sampling

    Science.gov (United States)

    Tipton, Elizabeth; Hedges, Larry; Vaden-Kiernan, Michael; Borman, Geoffrey; Sullivan, Kate; Caverly, Sarah

    2014-01-01

    Randomized experiments are often seen as the "gold standard" for causal research. Despite the fact that experiments use random assignment to treatment conditions, units are seldom selected into the experiment using probability sampling. Very little research on experimental design has focused on how to make generalizations to well-defined…

  4. Random sampling and validation of covariance matrices of resonance parameters

    Science.gov (United States)

    Plevnik, Lucijan; Zerovnik, Gašper

    2017-09-01

    Analytically exact methods for random sampling of arbitrary correlated parameters are presented. Emphasis is given on one hand on the possible inconsistencies in the covariance data, concentrating on the positive semi-definiteness and consistent sampling of correlated inherently positive parameters, and on the other hand on optimization of the implementation of the methods itself. The methods have been applied in the program ENDSAM, written in the Fortran language, which from a file from a nuclear data library of a chosen isotope in ENDF-6 format produces an arbitrary number of new files in ENDF-6 format which contain values of random samples of resonance parameters (in accordance with corresponding covariance matrices) in places of original values. The source code for the program ENDSAM is available from the OECD/NEA Data Bank. The program works in the following steps: reads resonance parameters and their covariance data from nuclear data library, checks whether the covariance data is consistent, and produces random samples of resonance parameters. The code has been validated with both realistic and artificial data to show that the produced samples are statistically consistent. Additionally, the code was used to validate covariance data in existing nuclear data libraries. A list of inconsistencies, observed in covariance data of resonance parameters in ENDF-VII.1, JEFF-3.2 and JENDL-4.0 is presented. For now, the work has been limited to resonance parameters, however the methods presented are general and can in principle be extended to sampling and validation of any nuclear data.

  5. Generalized and synthetic regression estimators for randomized branch sampling

    Science.gov (United States)

    David L. R. Affleck; Timothy G. Gregoire

    2015-01-01

    In felled-tree studies, ratio and regression estimators are commonly used to convert more readily measured branch characteristics to dry crown mass estimates. In some cases, data from multiple trees are pooled to form these estimates. This research evaluates the utility of both tactics in the estimation of crown biomass following randomized branch sampling (...

  6. Effective sampling of random surfaces by baby universe surgery

    NARCIS (Netherlands)

    Ambjørn, J.; Białas, P.; Jurkiewicz, J.; Burda, Z.; Petersson, B.

    1994-01-01

    We propose a new, very efficient algorithm for sampling of random surfaces in the Monte Carlo simulations, based on so-called baby universe surgery, i.e. cutting and pasting of baby universe. It drastically reduces slowing down as compared to the standard local flip algorithm, thereby allowing

  7. The role of self-efficacy, self-esteem and optimism for using routine health check-ups in a population-based sample. A longitudinal perspective.

    Science.gov (United States)

    Hajek, André; Hans-Helmut-König

    2017-12-01

    While several cross-sectional studies have shown that self-efficacy, self-esteem and optimism are associated with the use of routine health check-ups, little is known about this relationship based on longitudinal studies. Consequently, the purpose of this study was to examine whether these factors are associated with routine health check-ups longitudinally. Data were retrieved from a population-based longitudinal study of individuals (≥40years of age) residing in private households in Germany (two waves: 2008 and 2011). Widely established scales were used to quantify self-efficacy, self-esteem, and optimism. Respondents reported whether they used a health check-up in the last two years. Conditional fixed-effects logistic regressions were used (n=1504), adjusting for socio-demographic, lifestyle and health-related variables. After adjusting for various potential confounders, regression analysis revealed that the use of routine health check-ups increased with self-efficacy [OR: 1.71 (95%-CI: 1.14-2.55)], self-esteem [OR: 1.78 (1.16-2.73)], and optimism [OR: 1.37 (1.01-1.86)]. Furthermore, the use of routine health check-ups increased with changes from employment to retirement [OR: 2.60 (1.34-5.03)], whereas it was not associated with changes in age, marital status, smoking status, the number of physical illnesses, self-rated health and body-mass index. The current study stresses the importance of an association between screening behavior and self-efficacy, self-esteem and optimism longitudinally. Interventions aiming at modifying these psychological factors might help to increase the use of routine health check-ups. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Cerebrospinal Fluid Fatty Acid-Binding Protein 3 is Related to Dementia Development in a Population-Based Sample of Older Adult Women Followed for 8 Years.

    Science.gov (United States)

    Bjerke, Maria; Kern, Silke; Blennow, Kaj; Zetterberg, Henrik; Waern, Margda; Börjesson-Hanson, Anne; Östling, Svante; Kern, Jürgen; Skoog, Ingmar

    2016-01-01

    Increased fatty acid-binding protein 3 (FABP-3) levels have been reported in neurodegenerative diseases, including Alzheimer's disease (AD). Cerebrospinal fluid (CSF) FABP-3 has therefore been proposed as a putative marker for dementia. Population-based studies examining whether CSF FABP-3 predicts later development of dementia are lacking. The aim of this study was to examine CSF levels of FABP-3 in relation to later development of dementia in elderly women and in relation to Aβ42, T-tau, P-tau181, and CSF: serum albumin ratio. 86 non-demented women aged 70-84 years who participated in the Prospective Population Study of Women in Gothenburg, Sweden took part in a lumbar puncture in 1992-93. CSF-FABP-3, Aβ42, T-tau, P-tau181, and the CSF: serum albumin ratio were measured at baseline. Participants were examined with a neuropsychiatric exam at baseline and at follow-up in 2000. Dementia was diagnosed in accordance with DSM-III-R criteria. Between 1992 and 2000, 8 women developed dementia (4 AD, 3 vascular dementia, 1 mixed vascular dementia and AD). Higher levels of CSF-FABP-3 at baseline were related to development of dementia (OR 1.36 CI [1.05-1.76] p = 0.022) and the subtype AD (OR 1.38 CI [1.06-1.82), p = 0.019) during follow-up. FABP-3 correlated with CSF T-tau (r = 0.88, p dementia, probably related to neuronal degeneration, but independent of Aβ metabolism.

  9. A Population-Based Randomized Trial to Assess the Effects of Short-Term Cessation of Hormone Replacement Therapy on Mammography Assessments and Breast Density

    Science.gov (United States)

    2008-06-01

    mammograms, where recall was defined as any assessment requiring additional imaging or evaluation on either breast (BI-RADS assessment of 0). 7/10/2008 7... images are being randomly selected, rescanned and re-read for density outcomes on an ongoing basis. All mammographic breast density measures were...timing of the exam (index or study mammogram). To evaluate quality assurance, we included four inter-batch repeats and four intra-batch repeats within

  10. Development, problem behavior, and quality of life in a population based sample of eight-year-old children with down syndrome

    NARCIS (Netherlands)

    Gameren-Oosterom, H.B.M. van; Fekkes, M.; Buitendijk, S.E.; Mohangoo, A.D.; Bruil, J.; Wouwe, J.P. van

    2011-01-01

    Objective: Children with Down syndrome (DS) have delayed psychomotor development. We investigated levels of development, problem behavior, and Health-Related Quality of Life (HRQoL) in a population sample of Dutch eight-year-old children with DS. Developmental outcomes were compared with normative

  11. Long-Term Physical and Mental Health Consequences of Childhood Physical Abuse: Results from a Large Population-Based Sample of Men and Women

    Science.gov (United States)

    Springer, Kristen W.; Sheridan, Jennifer; Kuo, Daphne; Carnes, Molly

    2007-01-01

    Objective: Child maltreatment has been linked to negative adult health outcomes; however, much past research includes only clinical samples of women, focuses exclusively on sexual abuse and/or fails to control for family background and childhood characteristics, both potential confounders. Further research is needed to obtain accurate,…

  12. Random sampling and validation of covariance matrices of resonance parameters

    Directory of Open Access Journals (Sweden)

    Plevnik Lucijan

    2017-01-01

    Full Text Available Analytically exact methods for random sampling of arbitrary correlated parameters are presented. Emphasis is given on one hand on the possible inconsistencies in the covariance data, concentrating on the positive semi-definiteness and consistent sampling of correlated inherently positive parameters, and on the other hand on optimization of the implementation of the methods itself. The methods have been applied in the program ENDSAM, written in the Fortran language, which from a file from a nuclear data library of a chosen isotope in ENDF-6 format produces an arbitrary number of new files in ENDF-6 format which contain values of random samples of resonance parameters (in accordance with corresponding covariance matrices in places of original values. The source code for the program ENDSAM is available from the OECD/NEA Data Bank. The program works in the following steps: reads resonance parameters and their covariance data from nuclear data library, checks whether the covariance data is consistent, and produces random samples of resonance parameters. The code has been validated with both realistic and artificial data to show that the produced samples are statistically consistent. Additionally, the code was used to validate covariance data in existing nuclear data libraries. A list of inconsistencies, observed in covariance data of resonance parameters in ENDF-VII.1, JEFF-3.2 and JENDL-4.0 is presented. For now, the work has been limited to resonance parameters, however the methods presented are general and can in principle be extended to sampling and validation of any nuclear data.

  13. Noise sensitivity, rather than noise level, predicts the non-auditory effects of noise in community samples: a population-based survey

    OpenAIRE

    Park, Jangho; Chung, Seockhoon; Lee, Jiho; Sung, Joo Hyun; Cho, Seung Woo; Sim, Chang Sun

    2017-01-01

    Abstract Background Excessive noise affects human health and interferes with daily activities. Although environmental noise may not directly cause mental illness, it may accelerate and intensify the development of latent mental disorders. Noise sensitivity (NS) is considered a moderator of non-auditory noise effects. In the present study, we aimed to assess whether NS is associated with non-auditory effects. Methods We recruited a community sample of 1836 residents residing in Ulsan and Seoul...

  14. Trends in peptic ulcer disease and the identification of Helicobacter Pylori as a causative organism: Population-based estimates from the US nationwide inpatient sample

    Directory of Open Access Journals (Sweden)

    Bronislava Bashinskaya

    2011-01-01

    Full Text Available Background: Peptic ulcer disease can lead to serious complications including massive hemorrhage or bowel perforation. The modern treatment of peptic ulcer disease has transitioned from the control of gastric acid secretion to include antibiotic therapy in light of the identification of Helicobacter pylori as a causative infectious organism. We sought to determine trends related to this discovery by using a national database. Materials and Methods: Patient discharges with peptic ulcer disease and associated sequelae were queried from the Nationwide Inpatient Sample, 1993 to 2007, under the auspices of a data user agreement. To account for the Nationwide Inpatient Sample weighting schema, design-adjusted analyses were used. Standard error was calculated using SUDAAN software (Research Triangle International, NC, USA. Results: Decreases in the incidences of gastrointestinal perforation, gastrointestinal hemorrhage, and surgical procedures most specific to peptic ulcer disease were statistically significant over the study period [range of P value (two tailed = 0.000 - 0.00353; significant at P < 0.001 to < 0.01]. The incidence of H. pylori rose dramatically, peaking at an estimated 97,823 cases in 1998 [SE = 3155; 95% CI = 6,184]. Since that time it has decreased and then stabilized. Conclusions: The identification of H. pylori as the causative agent in the majority of peptic ulcer disease has revolutionized the understanding and management of the disease. Medical conditions and surgical procedures associated with end-stage peptic ulcer disease have significantly decreased according to analysis of selected index categories. Resident physician education objectives may need to be modified in light of these trends. Review Criteria: We reviewed patients with peptic ulcer disease. The database used was the Nationwide Inpatient Sample, 1993 to 2007. Message for the Clinic: Medical therapy has resulted in decreased morbidity from H. pylori infection as it

  15. Changes in Sexual Behavior and Attitudes Across Generations and Gender Among a Population-Based Probability Sample From an Urbanizing Province in Thailand.

    Science.gov (United States)

    Techasrivichien, Teeranee; Darawuttimaprakorn, Niphon; Punpuing, Sureeporn; Musumari, Patou Masika; Lukhele, Bhekumusa Wellington; El-Saaidi, Christina; Suguimoto, S Pilar; Feldman, Mitchell D; Ono-Kihara, Masako; Kihara, Masahiro

    2016-02-01

    Thailand has undergone rapid modernization with implications for changes in sexual norms. We investigated sexual behavior and attitudes across generations and gender among a probability sample of the general population of Nonthaburi province located near Bangkok in 2012. A tablet-based survey was performed among 2,138 men and women aged 15-59 years identified through a three-stage, stratified, probability proportional to size, clustered sampling. Descriptive statistical analysis was carried out accounting for the effects of multistage sampling. Relationship of age and gender to sexual behavior and attitudes was analyzed by bivariate analysis followed by multivariate logistic regression analysis to adjust for possible confounding. Patterns of sexual behavior and attitudes varied substantially across generations and gender. We found strong evidence for a decline in the age of sexual initiation, a shift in the type of the first sexual partner, and a greater rate of acceptance of adolescent premarital sex among younger generations. The study highlighted profound changes among young women as evidenced by a higher number of lifetime sexual partners as compared to older women. In contrast to the significant gender gap in older generations, sexual profiles of Thai young women have evolved to resemble those of young men with attitudes gradually converging to similar sexual standards. Our data suggest that higher education, being never-married, and an urban lifestyle may have been associated with these changes. Our study found that Thai sexual norms are changing dramatically. It is vital to continue monitoring such changes, considering the potential impact on the HIV/STIs epidemic and unintended pregnancies.

  16. HPV prevalence and genotype distribution in a population-based split-sample study of well-screened women using CLART HPV2 human papillomavirus genotype microarray system

    DEFF Research Database (Denmark)

    Bonde, Jesper; Rebolj, Matejka; Ejegod, Ditte Møller

    2014-01-01

    BACKGROUND: Human papillomavirus (HPV) genotyping assays are becoming increasingly attractive for use in mass screening, as they offer a possibility to integrate HPV screening with HPV vaccine monitoring, thereby generating a synergy between the two main modes of cervical cancer prevention......, Denmark, an area with a high background risk of cervical cancer where women aged 23-65 years are targeted for organized screening. METHODS: Material from 5,068 SurePath samples of women participating in routine screening and clinical follow-up of cervical abnormalities was tested using liquid based...

  17. Midlife Smoking, Apolipoprotein E and Risk of Dementia and Alzheimer's Disease: A Population-Based Cardiovascular Risk Factors, Aging and Dementia Study

    National Research Council Canada - National Science Library

    Rusanen, M; Rovio, S; Ngandu, T; Nissinen, A; Tuomilehto, J; Soininen, H; Kivipelto, M

    2010-01-01

    ...), and the possible modification of this relation by the apolipoprotein E (APOE) ε4. Methods: Participants of the Cardiovascular Risk Factors, Aging and Dementia study were randomly selected from population-based samples originally studied in midlife...

  18. HPV prevalence and genotype distribution in a population-based split-sample study of well-screened women using CLART HPV2 human papillomavirus genotype microarray system.

    Science.gov (United States)

    Bonde, Jesper; Rebolj, Matejka; Ejegod, Ditte Møller; Preisler, Sarah; Lynge, Elsebeth; Rygaard, Carsten

    2014-07-26

    Human papillomavirus (HPV) genotyping assays are becoming increasingly attractive for use in mass screening, as they offer a possibility to integrate HPV screening with HPV vaccine monitoring, thereby generating a synergy between the two main modes of cervical cancer prevention. The Genomica CLART HPV2 assay is a semi-automated PCR-based microarray assay detecting 35 high-risk and low-risk HPV genotypes. However, few reports have described this assay in cervical screening. An aim of the present study, Horizon, was to assess the prevalence of high-risk HPV infections in Copenhagen, Denmark, an area with a high background risk of cervical cancer where women aged 23-65 years are targeted for organized screening. Material from 5,068 SurePath samples of women participating in routine screening and clinical follow-up of cervical abnormalities was tested using liquid based cytology, CLART HPV2 and Hybrid Capture 2 (HC2). At least one of the 35 defined genotypes was detected by CLART in 1,896 (37%) samples. The most frequent high-risk genotypes were HPV 16 (7%), HPV 52 (5%), and HPV 31 (4%). The most frequent low-risk genotypes were HPV 53 (5%), HPV 61 (4%), and HPV 66 (3%). Among 4,793 women targeted by the screening program (23-65 years), 1,166 (24%) tested positive for one or more of the 13 high-risk genotypes. This proportion decreased from 40% at age 23-29 years to 10% at age 60-65 years. On HC2, 1,035 (20%) samples were positive for any high-risk and thus CLART showed a higher analytical sensitivity for 13 high-risk HPV genotypes than HC2, and this was found in all age-groups and in women normal cytology. CLART performed well with a positive reproducibility for high-risk genotypes of 86%, and a negative reproducibility of 97%. This report furthermore updates the genotype distribution in Denmark prior to the inclusion of the HPV-vaccinated cohorts into the screening program, and as such represents a valuable baseline for future vaccine impact assessment.

  19. Infertility Treatment and Fertility-Specific Distress: A Longitudinal Analysis of a Population-Based Sample of U.S. Women

    Science.gov (United States)

    Greil, Arthur L.; McQuillan, Julia; Lowry, Michele; Shreffler, Karina M.

    2011-01-01

    Because research on infertile women usually uses clinic-based samples of treatment seekers, it is difficult to sort out to what extent distress is the result of the condition of infertility itself and to what extent it is a consequence of the experience of infertility treatment. We use the National Survey of Fertility Barriers, a two-wave national probability sample of U.S. women, to disentangle the effects of infertility and infertility treatment on fertility-specific distress. Using a series of ANOVAs, we examine 266 infertile women who experienced infertility both at Wave 1 and at Wave 2, three years later. We compare eight groups of infertile women based on whether or not they have received treatment and on whether or not they have had a live birth. At Wave 1, infertile women who did not receive treatment and who had no live birth reported lower distress levels than women who received treatment at Wave 1 only, regardless of whether their infertility episode was followed by a live birth. At Wave 2, women who received no treatment have significantly lower fertility-specific distress than women who were treated at Wave 1 or at Waves 1 and 2, regardless of whether there was a subsequent live birth. Furthermore, fertility-specific distress did not increase over time among infertile women who did not receive treatment. The increase in fertility-specific distress was significantly higher for women who received treatment at Wave 2 that was not followed by a live birth than for women who received no treatment or for women who received treatment at Wave 1 only. These patterns suggest that infertility treatment is associated with levels of distress over and above those associated with the state of being infertile in and of itself. PMID:21645954

  20. Infertility treatment and fertility-specific distress: A longitudinal analysis of a population-based sample of U.S. women.

    Science.gov (United States)

    Greil, Arthur L; McQuillan, Julia; Lowry, Michele; Shreffler, Karina M

    2011-07-01

    Because research on infertile women usually uses clinic-based samples of treatment seekers, it is difficult to sort out to what extent distress is the result of the condition of infertility itself and to what extent it is a consequence of the experience of infertility treatment. We use the National Survey of Fertility Barriers, a two-wave national probability sample of U.S. women, to disentangle the effects of infertility and infertility treatment on fertility-specific distress. Using a series of ANOVAs, we examine 266 infertile women who experienced infertility both at Wave 1 and at Wave 2, three years later. We compare eight groups of infertile women based on whether or not they have received treatment and on whether or not they have had a live birth. At Wave 1, infertile women who did not receive treatment and who had no live birth reported lower distress levels than women who received treatment at Wave 1 only, regardless of whether their infertility episode was followed by a live birth. At Wave 2, women who received no treatment have significantly lower fertility-specific distress than women who were treated at Wave 1 or at Waves 1 and 2, regardless of whether there was a subsequent live birth. Furthermore, fertility-specific distress did not increase over time among infertile women who did not receive treatment. The increase infertility-specific distress was significantly higher for women who received treatment at Wave 2 that was not followed by a live birth than for women who received no treatment or for women who received treatment at Wave 1 only. These patterns suggest that infertility treatment is associated with levels of distress over and above those associated with the state of being infertile in and of itself. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Neuroanatomical Classification in a Population-Based Sample of Psychotic Major Depression and Bipolar I Disorder with 1 Year of Diagnostic Stability

    Directory of Open Access Journals (Sweden)

    Mauricio H. Serpa

    2014-01-01

    Full Text Available The presence of psychotic features in the course of a depressive disorder is known to increase the risk for bipolarity, but the early identification of such cases remains challenging in clinical practice. In the present study, we evaluated the diagnostic performance of a neuroanatomical pattern classification method in the discrimination between psychotic major depressive disorder (MDD, bipolar I disorder (BD-I, and healthy controls (HC using a homogenous sample of patients at an early course of their illness. Twenty-three cases of first-episode psychotic mania (BD-I and 19 individuals with a first episode of psychotic MDD whose diagnosis remained stable during 1 year of followup underwent 1.5 T MRI at baseline. A previously validated multivariate classifier based on support vector machine (SVM was employed and measures of diagnostic performance were obtained for the discrimination between each diagnostic group and subsamples of age- and gender-matched controls recruited in the same neighborhood of the patients. Based on T1-weighted images only, the SVM-classifier afforded poor discrimination in all 3 pairwise comparisons: BD-I versus HC; MDD versus HC; and BD-I versus MDD. Thus, at the population level and using structural MRI only, we failed to achieve good discrimination between BD-I, psychotic MDD, and HC in this proof of concept study.

  2. Oral Health Equity and Unmet Dental Care Needs in a Population-Based Sample: Findings From the Survey of the Health of Wisconsin

    Science.gov (United States)

    Wisk, Lauren E.; Walsh, Matthew; McWilliams, Christine; Eggers, Shoshannah; Olson, Melissa

    2015-01-01

    Objectives. We used objective oral health screening and survey data to explore individual-, psychosocial-, and community-level predictors of oral health status in a statewide population of adults. Methods. We examined oral health status in a sample of 1453 adult Wisconsin residents who participated in the Survey of the Health of Wisconsin Oral Health Screening project, conducted with the Wisconsin Department of Health Services during 2010. Results. We found significant disparities in oral health status across all individual-, psychosocial-, and community-level predictors. More than 15% of participants had untreated cavities, and 20% did not receive needed oral health care. Individuals who self-reported unmet need for dental care were 4 times as likely to have untreated cavities as were those who did not report such a need, after controlling for sociodemographic and behavioral factors. Conclusions. Our results suggested that costs were a primary predictor of access to care and poor oral health status. The results underscored the role that primary care, in conjunction with dental health care providers, could play in promoting oral health care, particularly in reducing barriers (e.g., the costs associated with unmet dental care) and promoting preventive health behaviors (e.g., teeth brushing). PMID:25905843

  3. Independent and joint associations of race/ethnicity and educational attainment with sleep-related symptoms in a population-based US sample.

    Science.gov (United States)

    Cunningham, Timothy J; Ford, Earl S; Chapman, Daniel P; Liu, Yong; Croft, Janet B

    2015-08-01

    Prior studies have documented disparities in short and long sleep duration, excessive daytime sleepiness, and insomnia by educational attainment and race/ethnicity separately. We examined both independent and interactive effects of these factors with a broader range of sleep indicators in a racially/ethnically diverse sample. We analyzed 2012 National Health Interview Survey data from 33,865 adults aged ≥18years. Sleep-related symptomatology included short sleep duration (≤6h), long sleep duration (≥9h), fatigue >3days, excessive daytime sleepiness, and insomnia. Bivariate analyses with chi-square tests and log-linear regression were performed. The overall age-adjusted prevalence was 29.1% for short sleep duration, 8.5% for long sleep duration, 15.1% for fatigue, 12.6% for excessive daytime sleepiness, and 18.8% for insomnia. Educational attainment and race/ethnicity were independently related to the five sleep-related symptoms. Among Whites, the likelihood of most sleep indicators increased as educational attainment decreased; relationships varied for the other racial/ethnic groups. For short sleep duration, the educational attainment-by-race/ethnicity interaction effect was significant for African Americans (ppopulation. Published by Elsevier Inc.

  4. Sampling Polymorphs of Ionic Solids using Random Superlattices.

    Science.gov (United States)

    Stevanović, Vladan

    2016-02-19

    Polymorphism offers rich and virtually unexplored space for discovering novel functional materials. To harness this potential approaches capable of both exploring the space of polymorphs and assessing their realizability are needed. One such approach devised for partially ionic solids is presented. The structure prediction part is carried out by performing local density functional theory relaxations on a large set of random supperlattices (RSLs) with atoms distributed randomly over different planes in a way that favors cation-anion coordination. Applying the RSL sampling on MgO, ZnO, and SnO_{2} reveals that the resulting probability of occurrence of a given structure offers a measure of its realizability explaining fully the experimentally observed, metastable polymorphs in these three systems.

  5. Noise sensitivity, rather than noise level, predicts the non-auditory effects of noise in community samples: a population-based survey

    Directory of Open Access Journals (Sweden)

    Jangho Park

    2017-04-01

    Full Text Available Abstract Background Excessive noise affects human health and interferes with daily activities. Although environmental noise may not directly cause mental illness, it may accelerate and intensify the development of latent mental disorders. Noise sensitivity (NS is considered a moderator of non-auditory noise effects. In the present study, we aimed to assess whether NS is associated with non-auditory effects. Methods We recruited a community sample of 1836 residents residing in Ulsan and Seoul, South Korea. From July to November 2015, participants were interviewed regarding their demographic characteristics, socioeconomic status, medical history, and NS. The non-auditory effects of noise were assessed using the Center of Epidemiologic Studies Depression, Insomnia Severity index, State Trait Anxiety Inventory state subscale, and Stress Response Inventory-Modified Form. Individual noise levels were recorded from noise maps. A three-model multivariate logistic regression analysis was performed to identify factors that might affect psychiatric illnesses. Results Participants ranged in age from 19 to 91 years (mean: 47.0 ± 16.1 years, and 37.9% (n = 696 were male. Participants with high NS were more likely to have been diagnosed with diabetes and hyperlipidemia and to use psychiatric medication. The multivariable analysis indicated that even after adjusting for noise-related variables, sociodemographic factors, medical illness, and duration of residence, subjects in the high NS group were more than 2 times more likely to experience depression and insomnia and 1.9 times more likely to have anxiety, compared with those in the low NS group. Noise exposure level was not identified as an explanatory value. Conclusions NS increases the susceptibility and hence moderates there actions of individuals to noise. NS, rather than noise itself, is associated with an elevated susceptibility to non-auditory effects.

  6. Noise sensitivity, rather than noise level, predicts the non-auditory effects of noise in community samples: a population-based survey.

    Science.gov (United States)

    Park, Jangho; Chung, Seockhoon; Lee, Jiho; Sung, Joo Hyun; Cho, Seung Woo; Sim, Chang Sun

    2017-04-12

    Excessive noise affects human health and interferes with daily activities. Although environmental noise may not directly cause mental illness, it may accelerate and intensify the development of latent mental disorders. Noise sensitivity (NS) is considered a moderator of non-auditory noise effects. In the present study, we aimed to assess whether NS is associated with non-auditory effects. We recruited a community sample of 1836 residents residing in Ulsan and Seoul, South Korea. From July to November 2015, participants were interviewed regarding their demographic characteristics, socioeconomic status, medical history, and NS. The non-auditory effects of noise were assessed using the Center of Epidemiologic Studies Depression, Insomnia Severity index, State Trait Anxiety Inventory state subscale, and Stress Response Inventory-Modified Form. Individual noise levels were recorded from noise maps. A three-model multivariate logistic regression analysis was performed to identify factors that might affect psychiatric illnesses. Participants ranged in age from 19 to 91 years (mean: 47.0 ± 16.1 years), and 37.9% (n = 696) were male. Participants with high NS were more likely to have been diagnosed with diabetes and hyperlipidemia and to use psychiatric medication. The multivariable analysis indicated that even after adjusting for noise-related variables, sociodemographic factors, medical illness, and duration of residence, subjects in the high NS group were more than 2 times more likely to experience depression and insomnia and 1.9 times more likely to have anxiety, compared with those in the low NS group. Noise exposure level was not identified as an explanatory value. NS increases the susceptibility and hence moderates there actions of individuals to noise. NS, rather than noise itself, is associated with an elevated susceptibility to non-auditory effects.

  7. Development, problem behavior, and quality of life in a population based sample of eight-year-old children with Down syndrome.

    Directory of Open Access Journals (Sweden)

    Helma B M van Gameren-Oosterom

    Full Text Available OBJECTIVE: Children with Down syndrome (DS have delayed psychomotor development. We investigated levels of development, problem behavior, and Health-Related Quality of Life (HRQoL in a population sample of Dutch eight-year-old children with DS. Developmental outcomes were compared with normative data of eight-year-old children from the general population. METHOD: Over a three-year-period all parents with an eight-year-old child with DS were approached by the national parent organization. Developmental skills were assessed by means of the McCarthy Scales of Children's Ability. To measure emotional and behavioral problems we used the Child Behavior Checklist. HRQoL was assessed with the TNO-AZL Children's Quality of Life questionnaire. Analyses of variance were applied to compare groups. RESULTS: A total of 337 children participated. Mean developmental age was substantially lower than mean calendar age (3.9 years, SD 0.87 and 8.1 years, SD 0.15 respectively. Mean developmental age was significantly lower among boys than girls (3.6 (SD 0.85 and 4.2 years (SD 0.82 respectively; p<0.001. Compared with the general population, children with DS had more emotional and behavioral problems (p<0.001. However on the anxious/depressed scale, they scored significantly more favorably (p<0.001. Significantly lower HRQoL scores for the scales gross motor skills, autonomy, social functioning and cognitive functioning were found (p-values<0.001. Hardly any differences were observed for the scales physical complaints, positive and negative emotions. CONCLUSION: Eight-year-old children with DS have an average developmental delay of four years, more often have emotional and behavioral problems, and have a less favorable HRQoL compared with children from the general population.

  8. Analysis of a global random stratified sample of nurse legislation.

    Science.gov (United States)

    Benton, D C; Fernández-Fernández, M P; González-Jurado, M A; Beneit-Montesinos, J V

    2015-06-01

    To identify, compare and contrast the major component parts of heterogeneous stratified sample of nursing legislation. Nursing legislation varies from one jurisdiction to another. Up until now no research exists into whether the variations of such legislation are random or if variations are related to a set of key attributes. This mixed method study used a random stratified sample of legislation to map through documentary analysis the content of 14 nursing acts and then explored, using quantitative techniques, whether the material contained relates to a number of key attributes. These attributes include: legal tradition of the jurisdiction; model of regulation; administrative approach; area of the world; and the economic status of the jurisdiction. Twelve component parts of nursing legislation were identified. These were remarkably similar irrespective of attributes of interest. However, not all component parts were specified in the same level of detail and the manner by which the elements were addressed did vary. A number of potential relationships between the structure of the legislation and the key attributes of interest were identified. This study generated a comprehensive and integrated map of a global sample of nursing legislation. It provides a set of descriptors to be used to undertake further quantitative work and provides an important policy tool to facilitate dialogue between regulatory bodies. At the individual nurse level it offers insights that can help nurses pursue recognition of credentials across jurisdictions. © 2015 International Council of Nurses.

  9. Neuromuscular exercise and counseling decrease absenteeism due to low back pain in young conscripts: a randomized, population-based primary prevention study.

    Science.gov (United States)

    Suni, Jaana H; Taanila, Henri; Mattila, Ville M; Ohrankämmen, Olli; Vuorinen, Petteri; Pihlajamäki, Harri; Parkkari, Jari

    2013-03-01

    Controlled intervention with group randomization. To investigate the effectiveness of a 6-month neuromuscular exercise and counseling program for reducing the incidence of low back pain (LBP) and disability in young conscripts, with a healthy back at the beginning of their compulsory military service. Basic military training is physically demanding on the back and requires adequate physical fitness. LBP causes significant morbidity and absence from military service. Participants were conscripts of 4 successive age cohorts (n = 1409). In the prestudy year, before adoption of the intervention, 2 successive cohorts of conscripts of 4 companies (n = 719) were followed prospectively for 6 months to study the baseline incidence of different categories of LBP. In the intervention year, conscripts (n = 690) of 2 new cohorts of the same companies (intervention group: antitank, engineer; control group: signal, mortar) were followed for 6 months. The intervention program aimed to improve conscripts' control of their lumbar neutral zone and specifically to avoid full lumbar flexion in all daily tasks. Total number and incidence of off-duty days due to LBP were significantly decreased in the intervention companies compared with controls (adjusted hazard ratio = 0.42, 95% confidence interval = 0.18-0.94, P = 0.035). The number of LBP cases, number of health clinic visits due to LBP, and number of the most severe cases showed a similar decreasing trend but without statistical significance. These findings provide evidence that exercise and education to improve control of the lumbar neutral zone have a prophylactic effect on LPB-related off-duty service days in the military environment when implemented as part of military service among young healthy men.

  10. Plasma Lutein and Zeaxanthin Are Associated With Better Cognitive Function Across Multiple Domains in a Large Population-Based Sample of Older Adults: Findings from The Irish Longitudinal Study on Aging.

    Science.gov (United States)

    Feeney, Joanne; O'Leary, Neil; Moran, Rachel; O'Halloran, Aisling M; Nolan, John M; Beatty, Stephen; Young, Ian S; Kenny, Rose Anne

    2017-10-01

    Low blood serum or plasma concentrations of the xanthophyll carotenoids lutein and zeaxanthin have been implicated in poorer cognitive health in older adults. However, equivocal results from smaller studies and clinical trials highlight the need for large population-based studies with comprehensive measures of cognitive function and adjustment for multiple confounders to examine such associations in more depth. In the current study, we investigated the association between plasma lutein and zeaxanthin and domain-specific cognitive performance in 4,076 community-dwelling adults aged 50 years or older from The Irish Longitudinal Study on Ageing. Mixed-effects models were fitted with adjustment for demographic and socioeconomic factors, health conditions, and health behaviors. Higher plasma lutein and zeaxanthin were independently associated with better composite scores across the domains of global cognition, memory, and executive function. We also found evidence that higher plasma zeaxanthin, but not lutein, was associated with better processing speed. These associations were consistent across domains. Further investigation of the prognostic value of carotenoid concentrations, and their changes, on cognition in similar population-based samples longitudinally is warranted.

  11. The Prevalence and Causes of Primary Infertility in Iran: A Population-Based Study

    OpenAIRE

    Kazemijaliseh, Hadigheh; Tehrani, Fahimeh Ramezani; Behboudi-Gandevani, Samira; Hosseinpanah, Farhad; Khalili, Davood; Azizi, Fereidoun

    2015-01-01

    Background: Primary infertility is a health issue among women over the world. The aim of this study was to investigate the prevalence and causes of primary infertility based on a population-based study in an urban area of Iran. Materials and Methods: In a cross-sectional study, a total of 1067 married women who participated in the Tehran Lipid and Glucose Study were randomly selected using systematic random sampling. Unmarried women, those with unwilling pregnancy and duration of marriage bel...

  12. Randomly Sampled-Data Control Systems. Ph.D. Thesis

    Science.gov (United States)

    Han, Kuoruey

    1990-01-01

    The purpose is to solve the Linear Quadratic Regulator (LQR) problem with random time sampling. Such a sampling scheme may arise from imperfect instrumentation as in the case of sampling jitter. It can also model the stochastic information exchange among decentralized controllers to name just a few. A practical suboptimal controller is proposed with the nice property of mean square stability. The proposed controller is suboptimal in the sense that the control structure is limited to be linear. Because of i. i. d. assumption, this does not seem unreasonable. Once the control structure is fixed, the stochastic discrete optimal control problem is transformed into an equivalent deterministic optimal control problem with dynamics described by the matrix difference equation. The N-horizon control problem is solved using the Lagrange's multiplier method. The infinite horizon control problem is formulated as a classical minimization problem. Assuming existence of solution to the minimization problem, the total system is shown to be mean square stable under certain observability conditions. Computer simulations are performed to illustrate these conditions.

  13. A Table-Based Random Sampling Simulation for Bioluminescence Tomography

    Directory of Open Access Journals (Sweden)

    Xiaomeng Zhang

    2006-01-01

    Full Text Available As a popular simulation of photon propagation in turbid media, the main problem of Monte Carlo (MC method is its cumbersome computation. In this work a table-based random sampling simulation (TBRS is proposed. The key idea of TBRS is to simplify multisteps of scattering to a single-step process, through randomly table querying, thus greatly reducing the computing complexity of the conventional MC algorithm and expediting the computation. The TBRS simulation is a fast algorithm of the conventional MC simulation of photon propagation. It retained the merits of flexibility and accuracy of conventional MC method and adapted well to complex geometric media and various source shapes. Both MC simulations were conducted in a homogeneous medium in our work. Also, we present a reconstructing approach to estimate the position of the fluorescent source based on the trial-and-error theory as a validation of the TBRS algorithm. Good agreement is found between the conventional MC simulation and the TBRS simulation.

  14. A comparison of methods for representing sparsely sampled random quantities.

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Vicente Jose; Swiler, Laura Painton; Urbina, Angel; Mullins, Joshua

    2013-09-01

    This report discusses the treatment of uncertainties stemming from relatively few samples of random quantities. The importance of this topic extends beyond experimental data uncertainty to situations involving uncertainty in model calibration, validation, and prediction. With very sparse data samples it is not practical to have a goal of accurately estimating the underlying probability density function (PDF). Rather, a pragmatic goal is that the uncertainty representation should be conservative so as to bound a specified percentile range of the actual PDF, say the range between 0.025 and .975 percentiles, with reasonable reliability. A second, opposing objective is that the representation not be overly conservative; that it minimally over-estimate the desired percentile range of the actual PDF. The presence of the two opposing objectives makes the sparse-data uncertainty representation problem interesting and difficult. In this report, five uncertainty representation techniques are characterized for their performance on twenty-one test problems (over thousands of trials for each problem) according to these two opposing objectives and other performance measures. Two of the methods, statistical Tolerance Intervals and a kernel density approach specifically developed for handling sparse data, exhibit significantly better overall performance than the others.

  15. Accelerating Markov chain Monte Carlo simulation by differential evolution with self-adaptive randomized subspace sampling

    Energy Technology Data Exchange (ETDEWEB)

    Vrugt, Jasper A [Los Alamos National Laboratory; Hyman, James M [Los Alamos National Laboratory; Robinson, Bruce A [Los Alamos National Laboratory; Higdon, Dave [Los Alamos National Laboratory; Ter Braak, Cajo J F [NETHERLANDS; Diks, Cees G H [UNIV OF AMSTERDAM

    2008-01-01

    Markov chain Monte Carlo (MCMC) methods have found widespread use in many fields of study to estimate the average properties of complex systems, and for posterior inference in a Bayesian framework. Existing theory and experiments prove convergence of well constructed MCMC schemes to the appropriate limiting distribution under a variety of different conditions. In practice, however this convergence is often observed to be disturbingly slow. This is frequently caused by an inappropriate selection of the proposal distribution used to generate trial moves in the Markov Chain. Here we show that significant improvements to the efficiency of MCMC simulation can be made by using a self-adaptive Differential Evolution learning strategy within a population-based evolutionary framework. This scheme, entitled DiffeRential Evolution Adaptive Metropolis or DREAM, runs multiple different chains simultaneously for global exploration, and automatically tunes the scale and orientation of the proposal distribution in randomized subspaces during the search. Ergodicity of the algorithm is proved, and various examples involving nonlinearity, high-dimensionality, and multimodality show that DREAM is generally superior to other adaptive MCMC sampling approaches. The DREAM scheme significantly enhances the applicability of MCMC simulation to complex, multi-modal search problems.

  16. The PsyCoLaus study: methodology and characteristics of the sample of a population-based survey on psychiatric disorders and their association with genetic and cardiovascular risk factors

    Directory of Open Access Journals (Sweden)

    Middleton Lefkos

    2009-03-01

    Full Text Available Abstract Background The Psychiatric arm of the population-based CoLaus study (PsyCoLaus is designed to: 1 establish the prevalence of threshold and subthreshold psychiatric syndromes in the 35 to 66 year-old population of the city of Lausanne (Switzerland; 2 test the validity of postulated definitions for subthreshold mood and anxiety syndromes; 3 determine the associations between psychiatric disorders, personality traits and cardiovascular diseases (CVD, 4 identify genetic variants that can modify the risk for psychiatric disorders and determine whether genetic risk factors are shared between psychiatric disorders and CVD. This paper presents the method as well as sociodemographic and somatic characteristics of the sample. Methods All 35 to 66 year-old persons previously selected for the population-based CoLaus survey on risk factors for CVD were asked to participate in a substudy assessing psychiatric conditions. This investigation included the Diagnostic Interview for Genetic Studies to elicit diagnostic criteria for threshold disorders according to DSM-IV and algorithmically defined subthreshold syndromes. Complementary information was collected on potential risk and protective factors for psychiatric disorders, migraine and on the morbidity of first-degree relatives, whereas the collection of DNA and plasma samples was already part of the original CoLaus survey. Results A total of 3,691 individuals completed the psychiatric evaluation (67% participation. The gender distribution of the sample did not differ significantly from that of the general population in the same age range. Although the youngest 5-year band of the cohort was underrepresented and the oldest 5-year band overrepresented, participants of PsyCoLaus and individuals who refused to participate revealed comparable scores on the General Health Questionnaire, a self-rating instrument completed at the somatic exam. Conclusion Despite limitations resulting from the relatively low

  17. Ajuste de varias ecuaciones de referencia espirométrica a una muestra poblacional en México Adjustment of several spirometric reference equations to a population-based sample in Mexico

    Directory of Open Access Journals (Sweden)

    Luis Torre-Bouscoulet

    2006-12-01

    Full Text Available OBJETIVOS: Comparar y determinar las ecuaciones de referencia para espirometría que mejor ajustan a una muestra poblacional. MATERIAL Y MÉTODOS: Se compararon los valores espirométricos de 225 sujetos sanos representativos de la población mayor de 40 años de la zona metropolitana de la Ciudad de México, con varias ecuaciones de referencia. El estudio se llevó a cabo entre junio y diciembre de 2003. RESULTADOS: Las ecuaciones que mejor ajustaron para FEV1 y FVC fueron NHANES III para mexicoestadounidenses y para euroestadounidenses, y la del estudio PLATINO. Los valores esperados por Knudson son menores que los observados, y los de Cruz Mérida son mayores. En el análisis del límite inferior de la normalidad, PLATINO fue el más cercano a 5% en el percentil 5. CONCLUSIONES: Mientras se obtienen valores de referencia con una muestra poblacional que cubra un mayor intervalo de edades, las ecuaciones que se recomiendan son NHANES III para mexicoestadounidenses o euroestadounidenses, así como la de PLATINO.OBJETIVE: To compare several forced spirometry reference equations used in Mexico in order to know which of them have a better fit to a population-based sample. MATERIAL AND METHODS: Spirometric values of 225 healthy subjects 40 years of age or older from Metropolitan area of Mexico City, were compared to several reference equations. The sample is population-based and it was done from June to December 2003. The difference between observed and expected values was calculated. A concordance analysis between both observed and expected values was done and the percentage of subjects under normality lower limit was obtained. RESULTS: The equations with better fit for FEV1 and FVC were: NHANES III for Mexican-Americans and Euro-Americans; and from PLATINO. Predicted values according to Knudson were lower, and those from Cruz-Mérida, larger than observed values. Percentage of subjects below lower limit of normal was closest to 5% in the reference

  18. Relationship between markers of insulin resistance, markers of adiposity, HbA1c, and cognitive functions in a middle-aged population-based sample: the MONA LISA study.

    Science.gov (United States)

    Sanz, Caroline M; Ruidavets, Jean-Bernard; Bongard, Vanina; Marquié, Jean-Claude; Hanaire, Hélène; Ferrières, Jean; Andrieu, Sandrine

    2013-06-01

    To determine the relationship between markers of insulin resistance (fasting insulin and homeostasis model assessment of insulin resistance), markers of adiposity (BMI, waist circumference, and body fat), HbA1c, and cognitive performances in a middle-aged population-based sample free of diabetes. Our study sample consisted of 1,172 people aged 35-64 years (49% women), free of diabetes, and recruited between 2005 and 2007 in the MONA LISA survey. Cognitive functions (memory, attention, and processing speed) were evaluated by neuropsychological tests: word-list learning test, digit symbol substitution test (DSST), word fluency test, and Stroop Test. Multiple logistic regressions were used to estimate the relationship between cognitive performance and metabolic markers. We serially adjusted for age, sex, education, and occupational status (model A), additionally for income, smoking, alcohol consumption, sedentarity, and psychotropic substance use (model B), and finally, included variables linked to the metabolic syndrome (hypertension, dyslipidemia, vascular disease, and C-reactive protein) and depression (model C). Elevated markers of adiposity were associated with poor cognitive performance in tests evaluating processing speed. The probability of being in the lowest quartile of each test was nearly doubled for participants in the upper quartile of BMI, compared with those in the lowest one [BMI, adjusted odds ratio (OR) 2.18, P = 0.003 (DSST), and OR 2.09, P = 0.005 (Stroop Test)]. High HbA1c was associated with poor cognitive performance in DSST (adjusted OR 1.75, P = 0.037). Waist circumference was linked to poor cognitive performance in men but not in women. Poor cognitive performance is associated with adiposity and hyperglycemia in healthy middle-aged people.

  19. A cross-sectional population-based study on the association of personality traits with anxiety and psychological stress: Joint modeling of mixed outcomes using shared random effects approach

    Directory of Open Access Journals (Sweden)

    Awat Feizi

    2014-01-01

    Full Text Available Background: Previous studies have showed some evidences about the relationship between personality traits particularly neuroticism and extroversion, separately, with psychological stress and anxiety. In the current study, we clarified the magnitude of joint interdependence (co-morbidity of anxiety (continuous and Psychological stress (dichotomous as dependent variables of mixed type with five-factor personality traits as independent variables. Materials and Methods: Data from 3180 participants who attended in the cross-sectional population-based "study on the epidemiology of psychological, alimentary health and nutrition" and completed self-administered questionnaires about demographic and life style, gastrointestinal disorders, personality traits, perceived intensity of stress, social support, and psychological outcome was analyzed using shared random effect approach in R Free software. Results: The results indicated high scores of neuroticism increase the chance of high psychological stress (odds ratio [OR] = 5.1; P < 0.001 and anxiety score (B = 1.73; P < 0.001 after adjustment for the probable confounders. In contrast, those who had higher scores of extraversion and conscientiousness experienced lower levels of anxiety score (B = −0.54 and −0.23, respectively, P < 0.001 and psychological stress (OR = 0.36 and 0.65, respectively, P < 0.001. Furthermore, higher score of agreeableness had significant negative relationship with anxiety (B = −0.32, P < 0.001. Conclusion: The present study indicated that the scores of neuroticism, extraversion, agreeableness and conscientiousness strongly predict both anxiety and psychological stress in Iranian adult population. Due to likely mechanism of genetic and environmental factors on the relationships between personality traits and psychological disorders, it is suggested to perform longitudinal studies focusing on both genetic and environmental factors in Iranian population.

  20. Cervical cancer screening in rural Bhutan with the careHPV test on self-collected samples: an ongoing cross-sectional, population-based study (REACH-Bhutan).

    Science.gov (United States)

    Baussano, Iacopo; Tshering, Sangay; Choden, Tashi; Lazzarato, Fulvio; Tenet, Vanessa; Plummer, Martyn; Franceschi, Silvia; Clifford, Gary M; Tshomo, Ugyen

    2017-07-19

    The Bhutanese Screening Programme recommends a Pap smear every 3 years for women aged 25-65 years, and coverage ranges from 20% to 60%, being especially challenging in rural settings. The 'REACH-Bhutan' study was conducted to assess the feasibility and outcomes of a novel approach to cervical cancer screening in rural Bhutan. Cross-sectional, population-based study of cervical cancer screening based on the careHPV test on self-collected samples. Women were recruited in rural primary healthcare centres, that is, Basic Health Units (BHU), across Bhutan. Overall, 3648 women aged 30-60 were invited from 15 BHUs differing in accessibility, size and ethnic composition of the population. Participants provided a self-collected cervicovaginal sample and were interviewed. Samples were tested using careHPV in Thimphu (the Bhutanese capital) referral laboratory. Screening participation by geographic area, centre, age and travelling time. Previous screening history and careHPV positivity by selected characteristics of the participants. In April/May 2016, 2590 women (median age: 41) were enrolled. Study participation was 71% and significantly heterogeneous by BHU (range: 31%-96%). Participation decreased with increase in age (81% in women aged 30-39 years; 59% in ≥50 years) and travelling time (90% in women living 6 hours away). 50% of participants reported no previous screening, with the proportion of never-screened women varying significantly by BHU (range: 2%-72%). 265 women (10%; 95% CI 9% to 11%) were careHPV positive, with a significant variation by BHU (range: 5%-19%) and number of sexual partners (prevalence ratio for ≥3 vs 0-1, 1.55; 95% CI 1.05 to 2.27). Community-based cervical cancer screening by testing self-collected samples for human papillomavirus (HPV) can achieve high coverage in rural Bhutan. However, solutions to bring self-collection, HPV testing and precancer treatment closer to the remotest villages are needed. © Article author(s) (or

  1. A population-based nested case control study on recurrent pneumonias in children with severe generalized cerebral palsy: ethical considerations of the design and representativeness of the study sample

    Directory of Open Access Journals (Sweden)

    Benninga Marc A

    2005-07-01

    -site measurements are of first choice, but timely inclusion is jeopardised. The initiation of this first study among children with severe neurological impairment led to specific, unexpected problems. Despite small differences between participants and non-participating children, our sample is as representative as can be expected from any population-based study and will provide important, new information to bring us further towards effective interventions to prevent pneumonias in this population.

  2. Factor structure and longitudinal invariance of the Center for Epidemiological Studies Depression Scale (CES-D) in adult women: application in a population-based sample of mothers of children with epilepsy.

    Science.gov (United States)

    Ferro, Mark A; Speechley, Kathy N

    2013-04-01

    The objective of this study was to examine the factor structure and longitudinal measurement invariance of the Center for Epidemiological Studies Depression Scale (CES-D). The population-based sample included 347 adult women who had children participating in the Health-related Quality of Life in Children with Epilepsy Study. Longitudinal confirmatory factor analysis was used to confirm the factor structure and test for measurement invariance. The original CES-D four-factor model (depressed affect, positive affect, somatic activity, and interpersonal relations) provided the best fit to the data compared to alternate models: [χ(2) = 362.95 (df = 164); Comparative Fit Index (CFI) = 965; Tucker-Lewis Index (TLI) = 0.960; Weighted Root Mean Square Residual (WRMR) = 0.966; Root Mean Square Error of Approximation (RMSEA) = 0.059, 90% confidence interval (CI), 0.051, 0.068] and was used for invariance testing. Results suggested full measurement invariance over time with the final model demonstrating adequate fit [χ(2) = 2303.92 (df = 1,776); CFI = 0.957; TLI = 0.952; WRMR = 1.149; RMSEA = 0.033, 90% CI, 0.030, 0.038]. We conclude that the four-factor structure of the CES-D is supported for adult women and that the measurement of the scale is longitudinally invariant. Clinicians and researchers can be confident that longitudinal changes in CES-D scores reflect true changes in depressive symptomatology and are not an artifact of changes in the interpretation of items in the scale over time.

  3. Sample size calculations for 3-level cluster randomized trials

    NARCIS (Netherlands)

    Teerenstra, S.; Moerbeek, M.; Achterberg, T. van; Pelzer, B.J.; Borm, G.F.

    2008-01-01

    BACKGROUND: The first applications of cluster randomized trials with three instead of two levels are beginning to appear in health research, for instance, in trials where different strategies to implement best-practice guidelines are compared. In such trials, the strategy is implemented in health

  4. Sample size calculations for 3-level cluster randomized trials

    NARCIS (Netherlands)

    Teerenstra, S.; Moerbeek, M.; Achterberg, T. van; Pelzer, B.J.; Borm, G.F.

    2008-01-01

    Background The first applications of cluster randomized trials with three instead of two levels are beginning to appear in health research, for instance, in trials where different strategies to implement best-practice guidelines are compared. In such trials, the strategy is implemented in health

  5. Improved estimator of finite population mean using auxiliary attribute in stratified random sampling

    OpenAIRE

    Verma, Hemant K.; Sharma, Prayas; Singh, Rajesh

    2014-01-01

    The present study discuss the problem of estimating the finite population mean using auxiliary attribute in stratified random sampling. In this paper taking the advantage of point bi-serial correlation between the study variable and auxiliary attribute, we have improved the estimation of population mean in stratified random sampling. The expressions for Bias and Mean square error have been derived under stratified random sampling. In addition, an empirical study has been carried out to examin...

  6. A Family of Estimators of a Sensitive Variable Using Auxiliary Information in Stratified Random Sampling

    Directory of Open Access Journals (Sweden)

    Nadia Mushtaq

    2017-03-01

    Full Text Available In this article, a combined general family of estimators is proposed for estimating finite population mean of a sensitive variable in stratified random sampling with non-sensitive auxiliary variable based on randomized response technique. Under stratified random sampling without replacement scheme, the expression of bias and mean square error (MSE up to the first-order approximations are derived. Theoretical and empirical results through a simulation study show that the proposed class of estimators is more efficient than the existing estimators, i.e., usual stratified random sample mean estimator, Sousa et al (2014 ratio and regression estimator of the sensitive variable in stratified sampling.

  7. At the intersection of criminal justice involvement and sexual orientation: Dynamic networks and health among a population-based sample of young Black men who have sex with men.

    Science.gov (United States)

    Schneider, J A; Lancki, N; Schumm, P

    2017-10-01

    Mass incarceration of young Black men has a significant impact on their network composition and stability that, in turn, may have major implications for health and well-being. A sub-group of young Black men with criminal justice involvement (CJI) identify as gay, bisexual or are non-identified men who have sex with men (hereafter MSM). This paper focuses on the potential effects of CJI on the composition of Black MSM social and sexual networks, their stability over time, and concomitant health and social outcomes. We use data from the UConnect study, a population-based cohort of young Black MSM 16-29 years of age (n=618) selected using respondent-driven sampling in Chicago from 2013-2016. Both confidant and sexual network name generators and interpreters were administered at 9-month intervals over three waves of data collection. Ego and dyadic-level data were collected on behaviors prevalent among MSM and including factors associated with network CJI, network stability, and health outcomes. Generalized Structural Equation Models (GSEM) were utilized to determine the relationship between CJI network composition, network stability and behaviors prevalent among young Black MSM and their networks. In the UConnect cohort, 46% had at least once been detained, arrested or spent time in jail or prison. In addition, 20% of participants reported incident CJI over the study period. Respondents with a history of CJI were significantly more likely to have CJI homophily in their confidant and sexual networks. Multivariate analyses demonstrate that the association between one's history of CJI, housing instability and drug use is partially explained by one's network CJI. In addition, a higher prevalence of network CJI is associated with increased turnover in the confidant network, and this network instability is also related to important health and social outcomes. This analysis describes the networks of criminal justice involved men among a representative sample of young Black

  8. Computer Corner: A Note on Pascal's Triangle and Simple Random Sampling.

    Science.gov (United States)

    Wright, Tommy

    1989-01-01

    Describes the algorithm used to select a simple random sample of certain size without having to list all possible samples and a justification based on Pascal's triangle. Provides testing results by various computers. (YP)

  9. Exponential ratio-product type estimators under second order approximation in stratified random sampling

    OpenAIRE

    Singh, Rajesh; Sharma, Prayas; Smarandache, Florentin

    2014-01-01

    Singh et al (20009) introduced a family of exponential ratio and product type estimators in stratified random sampling. Under stratified random sampling without replacement scheme, the expressions of bias and mean square error (MSE) of Singh et al (2009) and some other estimators, up to the first- and second-order approximations are derived. Also, the theoretical findings are supported by a numerical example.

  10. Query-Based Sampling: Can we do Better than Random?

    NARCIS (Netherlands)

    Tigelaar, A.S.; Hiemstra, Djoerd

    2010-01-01

    Many servers on the web offer content that is only accessible via a search interface. These are part of the deep web. Using conventional crawling to index the content of these remote servers is impossible without some form of cooperation. Query-based sampling provides an alternative to crawling

  11. Stratified random sampling plan for an irrigation customer telephone survey

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, J.W.; Davis, L.J.

    1986-05-01

    This report describes the procedures used to design and select a sample for a telephone survey of individuals who use electricity in irrigating agricultural cropland in the Pacific Northwest. The survey is intended to gather information on the irrigated agricultural sector that will be useful for conservation assessment, load forecasting, rate design, and other regional power planning activities.

  12. Fast egg collection method greatly improves randomness of egg sampling in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Schou, Mads Fristrup

    2013-01-01

    When obtaining samples for population genetic studies, it is essential that the sampling is random. For Drosophila, one of the crucial steps in sampling experimental flies is the collection of eggs. Here an egg collection method is presented, which randomizes the eggs in a water column and dimini......When obtaining samples for population genetic studies, it is essential that the sampling is random. For Drosophila, one of the crucial steps in sampling experimental flies is the collection of eggs. Here an egg collection method is presented, which randomizes the eggs in a water column...... and to obtain a representative collection of genotypes, the method presented here is strongly recommended when collecting eggs from Drosophila....

  13. Parameter Estimation in Stratified Cluster Sampling under Randomized Response Models for Sensitive Question Survey.

    Science.gov (United States)

    Pu, Xiangke; Gao, Ge; Fan, Yubo; Wang, Mian

    2016-01-01

    Randomized response is a research method to get accurate answers to sensitive questions in structured sample survey. Simple random sampling is widely used in surveys of sensitive questions but hard to apply on large targeted populations. On the other side, more sophisticated sampling regimes and corresponding formulas are seldom employed to sensitive question surveys. In this work, we developed a series of formulas for parameter estimation in cluster sampling and stratified cluster sampling under two kinds of randomized response models by using classic sampling theories and total probability formulas. The performances of the sampling methods and formulas in the survey of premarital sex and cheating on exams at Soochow University were also provided. The reliability of the survey methods and formulas for sensitive question survey was found to be high.

  14. Parameter Estimation in Stratified Cluster Sampling under Randomized Response Models for Sensitive Question Survey.

    Directory of Open Access Journals (Sweden)

    Xiangke Pu

    Full Text Available Randomized response is a research method to get accurate answers to sensitive questions in structured sample survey. Simple random sampling is widely used in surveys of sensitive questions but hard to apply on large targeted populations. On the other side, more sophisticated sampling regimes and corresponding formulas are seldom employed to sensitive question surveys. In this work, we developed a series of formulas for parameter estimation in cluster sampling and stratified cluster sampling under two kinds of randomized response models by using classic sampling theories and total probability formulas. The performances of the sampling methods and formulas in the survey of premarital sex and cheating on exams at Soochow University were also provided. The reliability of the survey methods and formulas for sensitive question survey was found to be high.

  15. A Unified Approach to Power Calculation and Sample Size Determination for Random Regression Models

    Science.gov (United States)

    Shieh, Gwowen

    2007-01-01

    The underlying statistical models for multiple regression analysis are typically attributed to two types of modeling: fixed and random. The procedures for calculating power and sample size under the fixed regression models are well known. However, the literature on random regression models is limited and has been confined to the case of all…

  16. A Family of Estimators of a Sensitive Variable Using Auxiliary Information in Stratified Random Sampling

    National Research Council Canada - National Science Library

    Nadia Mushtaq; Noor Ul Amin; Muhammad Hanif

    2017-01-01

    In this article, a combined general family of estimators is proposed for estimating finite population mean of a sensitive variable in stratified random sampling with non-sensitive auxiliary variable...

  17. A New Estimator For Population Mean Using Two Auxiliary Variables in Stratified random Sampling

    OpenAIRE

    Singh, Rajesh; Malik, Sachin

    2014-01-01

    In this paper, we suggest an estimator using two auxiliary variables in stratified random sampling. The propose estimator has an improvement over mean per unit estimator as well as some other considered estimators. Expressions for bias and MSE of the estimator are derived up to first degree of approximation. Moreover, these theoretical findings are supported by a numerical example with original data. Key words: Study variable, auxiliary variable, stratified random sampling, bias and mean squa...

  18. Conflict-cost based random sampling design for parallel MRI with low rank constraints

    Science.gov (United States)

    Kim, Wan; Zhou, Yihang; Lyu, Jingyuan; Ying, Leslie

    2015-05-01

    In compressed sensing MRI, it is very important to design sampling pattern for random sampling. For example, SAKE (simultaneous auto-calibrating and k-space estimation) is a parallel MRI reconstruction method using random undersampling. It formulates image reconstruction as a structured low-rank matrix completion problem. Variable density (VD) Poisson discs are typically adopted for 2D random sampling. The basic concept of Poisson disc generation is to guarantee samples are neither too close to nor too far away from each other. However, it is difficult to meet such a condition especially in the high density region. Therefore the sampling becomes inefficient. In this paper, we present an improved random sampling pattern for SAKE reconstruction. The pattern is generated based on a conflict cost with a probability model. The conflict cost measures how many dense samples already assigned are around a target location, while the probability model adopts the generalized Gaussian distribution which includes uniform and Gaussian-like distributions as special cases. Our method preferentially assigns a sample to a k-space location with the least conflict cost on the circle of the highest probability. To evaluate the effectiveness of the proposed random pattern, we compare the performance of SAKEs using both VD Poisson discs and the proposed pattern. Experimental results for brain data show that the proposed pattern yields lower normalized mean square error (NMSE) than VD Poisson discs.

  19. Anxiety disorders in young people: a population-based study

    Directory of Open Access Journals (Sweden)

    Thaíse Campos Mondin

    2013-12-01

    Full Text Available Objective: To assess the prevalence of anxiety disorders and associated factors in young adults. Methods: Cross-sectional population-based study of individuals between the ages of 18 and 24 years randomly selected from 89 census-based sectors to ensure an adequate sample size. Household selection within the sectors was performed according to a systematic sampling process. Anxiety disorders were assessed using the Mini International Neuropsychiatric Interview (MINI. The final sample comprised 1,560 young adults. Results: Of the participants who were diagnosed with anxiety disorders, 12.3% had agoraphobia, 9.7% had generalised anxiety disorder, 4.0% had social phobia, 3.3% had obsessive-compulsive disorder, 2.5% had panic disorder, and 2.1% had post-traumatic stress disorder; only 23.8% had received any previous treatment. Anxiety disorders were associated with sex, socioeconomic status, psychiatric problems in parents, alcohol abuse, and tobacco use. Conclusions: The identification of factors associated with anxiety disorders in young people enables us to develop intervention strategies. Anxiety disorders are not only highly prevalent but are also associated with significant functional impairment, significant reductions in quality of life, lower productivity, and higher rates of comorbidities.

  20. Internal consistency, concurrent validity, and discriminant validity of a measure of public support for policies for active living in transportation (PAL-T) in a population-based sample of adults.

    Science.gov (United States)

    Fuller, Daniel; Gauvin, Lise; Fournier, Michel; Kestens, Yan; Daniel, Mark; Morency, Patrick; Drouin, Louis

    2012-04-01

    Active living is a broad conceptualization of physical activity that incorporates domains of exercise; recreational, household, and occupational activities; and active transportation. Policy makers develop and implement a variety of transportation policies that can influence choices about how to travel from one location to another. In making such decisions, policy makers act in part in response to public opinion or support for proposed policies. Measures of the public's support for policies aimed at promoting active transportation can inform researchers and policy makers. This study examined the internal consistency, and concurrent and discriminant validity of a newly developed measure of the public's support for policies for active living in transportation (PAL-T). A series of 17 items representing potential policies for promoting active transportation was generated. Two samples of participants (n = 2,001 and n = 2,502) from Montreal, Canada, were recruited via random digit dialling. Analyses were conducted on the combined data set (n = 4,503). Participants were aged 18 through 94 years (58% female). The concurrent and discriminant validity of the PAL-T was assessed by examining relationships with physical activity and smoking. To explore the usability of the PAL-T, predicted scale scores were compared to the summed values of responses. Results showed that the internal consistency of the PAL-T was 0.70. Multilevel regression demonstrated no relationship between the PAL-T and smoking status (p > 0.05) but significant relationships with utilitarian walking (p public opinion can inform policy makers and support advocacy efforts aimed at making built environments more suitable for active transportation while allowing researchers to examine the antecedents and consequences of public support for policies.

  1. Misrepresenting random sampling? A systematic review of research papers in the Journal of Advanced Nursing.

    Science.gov (United States)

    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.

  2. Comparison of kriging interpolation precision between grid sampling scheme and simple random sampling scheme for precision agriculture

    Directory of Open Access Journals (Sweden)

    Jiang Houlong

    2016-01-01

    Full Text Available Sampling methods are important factors that can potentially limit the accuracy of predictions of spatial distribution patterns. A 10 ha tobacco-planted field was selected to compared the accuracy in predicting the spatial distribution of soil properties by using ordinary kriging and cross validation methods between grid sampling and simple random sampling scheme (SRS. To achieve this objective, we collected soil samples from the topsoil (0-20 cm in March 2012. Sample numbers of grid sampling and SRS were both 115 points each. Accuracies of spatial interpolation using the two sampling schemes were then evaluated based on validation samples (36 points and deviations of the estimates. The results suggested that soil pH and nitrate-N (NO3-N had low variation, whereas all other soil properties exhibited medium variation. Soil pH, organic matter (OM, total nitrogen (TN, cation exchange capacity (CEC, total phosphorus (TP and available phosphorus (AP matched the spherical model, whereas the remaining variables fit an exponential model with both sampling methods. The interpolation error of soil pH, TP, and AP was the lowest in SRS. The errors of interpolation for OM, CEC, TN, available potassium (AK and total potassium (TK were the lowest for grid sampling. The interpolation precisions of the soil NO3-N showed no significant differences between the two sampling schemes. Considering our data on interpolation precision and the importance of minerals for cultivation of flue-cured tobacco, the grid-sampling scheme should be used in tobacco-planted fields to determine the spatial distribution of soil properties. The grid-sampling method can be applied in a practical and cost-effective manner to facilitate soil sampling in tobacco-planted field.

  3. Risk perception among women receiving genetic counseling: a population-based follow-up study

    DEFF Research Database (Denmark)

    Mikkelsen, Ellen M; Sunde, Lone; Johansen, Christoffer

    2007-01-01

    . CONCLUSION: This population-based study of women with a family history of breast or ovarian cancer indicates that genetic counseling can help them both to reduce their perceived risk and to achieve a more realistic view of their risk of developing breast cancer. Udgivelsesdato: 2007-null......BACKGROUND: We aimed to explore the impact of genetic counseling on perceived personal lifetime risk of breast cancer, the accuracy of risk perception, and possible predictors of inaccurate risk perception 1 year following counseling. METHODS: We conducted a population-based prospective follow......-up study of 213 women who received genetic counseling for hereditary breast and ovarian cancer, 319 women who underwent mammography (Reference Group I), and a random sample of 1070 women from the general population (Reference Group II). RESULTS: Women who received genetic counseling decreased...

  4. Calculating sample sizes for cluster randomized trials: we can keep it simple and efficient !

    NARCIS (Netherlands)

    van Breukelen, Gerard J.P.; Candel, Math J.J.M.

    2012-01-01

    Objective: Simple guidelines for efficient sample sizes in cluster randomized trials with unknown intraclass correlation and varying cluster sizes. Methods: A simple equation is given for the optimal number of clusters and sample size per cluster. Here, optimal means maximizing power for a given

  5. Multidimensional Prognostic Index in Association with Future Mortality and Number of Hospital Days in a Population-Based Sample of Older Adults: Results of the EU Funded MPI_AGE Project.

    Science.gov (United States)

    Angleman, Sara B; Santoni, Giola; Pilotto, Alberto; Fratiglioni, Laura; Welmer, Anna-Karin

    2015-01-01

    The Multidimensional Prognostic Index (MPI) has been found to predict mortality in patients with a variety of clinical conditions. We aimed to assess the association of the MPI with future mortality and number of in-hospital days for the first time in a population-based cohort. The study population consisted of 2472 persons, aged 66-99 years, from the Swedish National Study on Aging and Care in Kungsholmen, Sweden, who underwent the baseline visit 2001-4, and were followed up >10 years for in-hospital days and >12 years for mortality. The MPI was a modified version of the original and aggregated seven domains (personal and instrumental activities of daily living, cognitive function, illness severity and comorbidity, number of medications, co-habitation status, and nutritional status). The MPI score was divided into risk groups: low, medium and high. Number of in-hospital days (within 1, 3 and 10 years) and mortality data were derived from official registries. All analyses were age-stratified (sexagenarians, septuagenarians, octogenarians, nonagenarians). During the follow-up 1331 persons (53.8%) died. Laplace regression models, suggested that median survival in medium risk groups varied by age from 2.2-3.6 years earlier than for those in the corresponding low risk groups (p = 0.002-p<0.001), and median survival in high risk groups varied by age from 3.8-9.0 years earlier than for corresponding low risk groups (p<0.001). For nonagenarians, the median age at death was 3.8 years earlier in the high risk group than for the low risk group (p<0.001). The mean number of in-hospital days increased significantly with higher MPI risk score within 1 and 3 years for people of each age group. For the first time, the effectiveness of MPI has been verified in a population-based cohort. Higher MPI risk scores associated with more days in hospital and with fewer years of survival, across a broad and stratified age range.

  6. Multidimensional Prognostic Index in Association with Future Mortality and Number of Hospital Days in a Population-Based Sample of Older Adults: Results of the EU Funded MPI_AGE Project.

    Directory of Open Access Journals (Sweden)

    Sara B Angleman

    Full Text Available The Multidimensional Prognostic Index (MPI has been found to predict mortality in patients with a variety of clinical conditions. We aimed to assess the association of the MPI with future mortality and number of in-hospital days for the first time in a population-based cohort.The study population consisted of 2472 persons, aged 66-99 years, from the Swedish National Study on Aging and Care in Kungsholmen, Sweden, who underwent the baseline visit 2001-4, and were followed up >10 years for in-hospital days and >12 years for mortality. The MPI was a modified version of the original and aggregated seven domains (personal and instrumental activities of daily living, cognitive function, illness severity and comorbidity, number of medications, co-habitation status, and nutritional status. The MPI score was divided into risk groups: low, medium and high. Number of in-hospital days (within 1, 3 and 10 years and mortality data were derived from official registries. All analyses were age-stratified (sexagenarians, septuagenarians, octogenarians, nonagenarians.During the follow-up 1331 persons (53.8% died. Laplace regression models, suggested that median survival in medium risk groups varied by age from 2.2-3.6 years earlier than for those in the corresponding low risk groups (p = 0.002-p<0.001, and median survival in high risk groups varied by age from 3.8-9.0 years earlier than for corresponding low risk groups (p<0.001. For nonagenarians, the median age at death was 3.8 years earlier in the high risk group than for the low risk group (p<0.001. The mean number of in-hospital days increased significantly with higher MPI risk score within 1 and 3 years for people of each age group.For the first time, the effectiveness of MPI has been verified in a population-based cohort. Higher MPI risk scores associated with more days in hospital and with fewer years of survival, across a broad and stratified age range.

  7. Survey research with a random digit dial national mobile phone sample in Ghana: Methods and sample quality

    Science.gov (United States)

    Sefa, Eunice; Adimazoya, Edward Akolgo; Yartey, Emmanuel; Lenzi, Rachel; Tarpo, Cindy; Heward-Mills, Nii Lante; Lew, Katherine; Ampeh, Yvonne

    2018-01-01

    Introduction Generating a nationally representative sample in low and middle income countries typically requires resource-intensive household level sampling with door-to-door data collection. High mobile phone penetration rates in developing countries provide new opportunities for alternative sampling and data collection methods, but there is limited information about response rates and sample biases in coverage and nonresponse using these methods. We utilized data from an interactive voice response, random-digit dial, national mobile phone survey in Ghana to calculate standardized response rates and assess representativeness of the obtained sample. Materials and methods The survey methodology was piloted in two rounds of data collection. The final survey included 18 demographic, media exposure, and health behavior questions. Call outcomes and response rates were calculated according to the American Association of Public Opinion Research guidelines. Sample characteristics, productivity, and costs per interview were calculated. Representativeness was assessed by comparing data to the Ghana Demographic and Health Survey and the National Population and Housing Census. Results The survey was fielded during a 27-day period in February-March 2017. There were 9,469 completed interviews and 3,547 partial interviews. Response, cooperation, refusal, and contact rates were 31%, 81%, 7%, and 39% respectively. Twenty-three calls were dialed to produce an eligible contact: nonresponse was substantial due to the automated calling system and dialing of many unassigned or non-working numbers. Younger, urban, better educated, and male respondents were overrepresented in the sample. Conclusions The innovative mobile phone data collection methodology yielded a large sample in a relatively short period. Response rates were comparable to other surveys, although substantial coverage bias resulted from fewer women, rural, and older residents completing the mobile phone survey in

  8. Low Physical Activity and Its Association with Diabetes and Other Cardiovascular Risk Factors: A Nationwide, Population-Based Study.

    OpenAIRE

    Brugnara, Laura; Goday Arno, Alberto; Ortega, Emilio

    2016-01-01

    Low physical activity (PA), or sedentary lifestyle, is associated with the development of several chronic diseases. We aimed to investigate current prevalence of sedentariness and its association with diabetes and other cardiovascular risk factors. PA was evaluated in a population-based, cross-sectional, randomly sampled study conducted in 2009-2010 in Spain. International Physical Activity Questionnaire (SF-IPAQ) was used to assess PA. 4991 individuals (median age 50 years, 57% women) were s...

  9. Stratified random sampling for estimating billing accuracy in health care systems.

    Science.gov (United States)

    Buddhakulsomsiri, Jirachai; Parthanadee, Parthana

    2008-03-01

    This paper presents a stratified random sampling plan for estimating accuracy of bill processing performance for the health care bills submitted to third party payers in health care systems. Bill processing accuracy is estimated with two measures: percent accuracy and total dollar accuracy. Difficulties in constructing a sampling plan arise when the population strata structure is unknown, and when the two measures require different sampling schemes. To efficiently utilize sample resource, the sampling plan is designed to effectively estimate both measures from the same sample. The sampling plan features a simple but efficient strata construction method, called rectangular method, and two accuracy estimation methods, one for each measure. The sampling plan is tested on actual populations from an insurance company. Accuracy estimates obtained are then used to compare the rectangular method to other potential clustering methods for strata construction, and compare the accuracy estimation methods to other eligible methods. Computational study results show effectiveness of the proposed sampling plan.

  10. SNP selection and classification of genome-wide SNP data using stratified sampling random forests.

    Science.gov (United States)

    Wu, Qingyao; Ye, Yunming; Liu, Yang; Ng, Michael K

    2012-09-01

    For high dimensional genome-wide association (GWA) case-control data of complex disease, there are usually a large portion of single-nucleotide polymorphisms (SNPs) that are irrelevant with the disease. A simple random sampling method in random forest using default mtry parameter to choose feature subspace, will select too many subspaces without informative SNPs. Exhaustive searching an optimal mtry is often required in order to include useful and relevant SNPs and get rid of vast of non-informative SNPs. However, it is too time-consuming and not favorable in GWA for high-dimensional data. The main aim of this paper is to propose a stratified sampling method for feature subspace selection to generate decision trees in a random forest for GWA high-dimensional data. Our idea is to design an equal-width discretization scheme for informativeness to divide SNPs into multiple groups. In feature subspace selection, we randomly select the same number of SNPs from each group and combine them to form a subspace to generate a decision tree. The advantage of this stratified sampling procedure can make sure each subspace contains enough useful SNPs, but can avoid a very high computational cost of exhaustive search of an optimal mtry, and maintain the randomness of a random forest. We employ two genome-wide SNP data sets (Parkinson case-control data comprised of 408 803 SNPs and Alzheimer case-control data comprised of 380 157 SNPs) to demonstrate that the proposed stratified sampling method is effective, and it can generate better random forest with higher accuracy and lower error bound than those by Breiman's random forest generation method. For Parkinson data, we also show some interesting genes identified by the method, which may be associated with neurological disorders for further biological investigations.

  11. Random Walks on Directed Networks: Inference and Respondent-driven Sampling

    CERN Document Server

    Malmros, Jens; Britton, Tom

    2013-01-01

    Respondent driven sampling (RDS) is a method often used to estimate population properties (e.g. sexual risk behavior) in hard-to-reach populations. It combines an effective modified snowball sampling methodology with an estimation procedure that yields unbiased population estimates under the assumption that the sampling process behaves like a random walk on the social network of the population. Current RDS estimation methodology assumes that the social network is undirected, i.e. that all edges are reciprocal. However, empirical social networks in general also have non-reciprocated edges. To account for this fact, we develop a new estimation method for RDS in the presence of directed edges on the basis of random walks on directed networks. We distinguish directed and undirected edges and consider the possibility that the random walk returns to its current position in two steps through an undirected edge. We derive estimators of the selection probabilities of individuals as a function of the number of outgoing...

  12. Population-based study of presbyopia in Nicaragua.

    Science.gov (United States)

    Hookway, Larry A; Frazier, Marcela; Rivera, Nelson; Ramson, Prasidh; Carballo, Luis; Naidoo, Kovin

    2016-11-01

    Uncorrected presbyopia can greatly impact a person's quality of life and employment prospects. Nicaragua is the poorest country in Latin America and there are no population-based reports of prevalence of presbyopia in Nicaragua. A cross-sectional population-based household survey was conducted. The sample was selected through random cluster sampling. Adults 35 years and older were enlisted through a door-to-door method using aged-based sampling. All enumerated household members 35 years and older were asked to attend a free visual acuity screening. Autorefraction was done and then uncorrected distance vision and near visual acuity were measured for all subjects. All those who had distance or near vision that was 6/12 or worse underwent a clinical examination, which included refraction at distance and near. Free spectacles were provided. Of the 3,390 subjects surveyed, 37.1 per cent reported that they wore spectacles on a regular basis. A total of 1,871 (55.2 per cent) of those enumerated were examined. The prevalence of near visual impairment (6/12 [N 6] or worse) was 79.6 per cent for the 35 to 49-year-old group, 97.3 per cent for the 50 to 64-year-old group and 96.7 per cent for the 65 and over group. Of those reporting for the examination, 82.2 per cent did not have glasses. Of those examined, 10 per cent did not need spectacles, four per cent were given spectacles for distance only, 38 per cent spectacles for distance and near, 42 per cent spectacles for near only and seven per cent were referred for medical evaluation due to ocular pathology. During the refractions, 91.5 per cent were corrected to 6/12 or better at distance and 89.4 per cent were corrected to 6/12 or better at near. The majority of the participants who were examined did not have the spectacles that they needed. Over one-third of those participants who presented without spectacles had distance vision better than 6/12 and could be improved to good near vision with ready-made near-only spectacles

  13. Population-based study of presbyopia in Shahroud, Iran.

    Science.gov (United States)

    Hashemi, Hassan; Khabazkhoob, Mehdi; Jafarzadehpur, Ebrahim; Mehravaran, Shiva; Emamian, Mohammad Hassan; Yekta, AbbasAli; Shariati, Mohammad; Fotouhi, Akbar

    2012-12-01

    There is limited information regarding the prevalence of presbyopia in different parts of the world. The add power and the prevalence of presbyopia by age and gender in general population of Shahroud, north of Iran, were studied. Population-based cross-sectional study. Using random cluster sampling, 6311 people from the 40- to 64-year-old population of Shahroud were invited. Of the invited population, 5190 individuals (82.2%) participated in the study. Presbyopia was defined as the correction of near vision to logMAR 1 (N8 point) with at least 1 D of add power. Near visual acuity of participants was evaluated with a logMAR chart at a distance of 40 cm. Mean add power in the age groups of 40-44, 45-49, 50-54, 55-59 and 60-64 years was 0.65, 1.30, 1.70, 1.87 and 2.08 D, respectively. For each 5-year increase in age, a 0.35 D increase in add power was noted. The prevalence of presbyopia was 58.15% (95% confidence interval: 56.46-59.84). Presbyopia was more prevalent in women (P presbyopia was less prevalent. More than 50% of the over 45-year-old individuals were presbyopic and 17% of the over 60 individuals were free of this condition. © 2012 The Authors. Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.

  14. Estimation of Sensitive Proportion by Randomized Response Data in Successive Sampling

    Directory of Open Access Journals (Sweden)

    Bo Yu

    2015-01-01

    Full Text Available This paper considers the problem of estimation for binomial proportions of sensitive or stigmatizing attributes in the population of interest. Randomized response techniques are suggested for protecting the privacy of respondents and reducing the response bias while eliciting information on sensitive attributes. In many sensitive question surveys, the same population is often sampled repeatedly on each occasion. In this paper, we apply successive sampling scheme to improve the estimation of the sensitive proportion on current occasion.

  15. Random sampling of elementary flux modes in large-scale metabolic networks.

    Science.gov (United States)

    Machado, Daniel; Soons, Zita; Patil, Kiran Raosaheb; Ferreira, Eugénio C; Rocha, Isabel

    2012-09-15

    The description of a metabolic network in terms of elementary (flux) modes (EMs) provides an important framework for metabolic pathway analysis. However, their application to large networks has been hampered by the combinatorial explosion in the number of modes. In this work, we develop a method for generating random samples of EMs without computing the whole set. Our algorithm is an adaptation of the canonical basis approach, where we add an additional filtering step which, at each iteration, selects a random subset of the new combinations of modes. In order to obtain an unbiased sample, all candidates are assigned the same probability of getting selected. This approach avoids the exponential growth of the number of modes during computation, thus generating a random sample of the complete set of EMs within reasonable time. We generated samples of different sizes for a metabolic network of Escherichia coli, and observed that they preserve several properties of the full EM set. It is also shown that EM sampling can be used for rational strain design. A well distributed sample, that is representative of the complete set of EMs, should be suitable to most EM-based methods for analysis and optimization of metabolic networks. Source code for a cross-platform implementation in Python is freely available at http://code.google.com/p/emsampler. dmachado@deb.uminho.pt Supplementary data are available at Bioinformatics online.

  16. Power and sample size calculations for Mendelian randomization studies using one genetic instrument.

    Science.gov (United States)

    Freeman, Guy; Cowling, Benjamin J; Schooling, C Mary

    2013-08-01

    Mendelian randomization, which is instrumental variable analysis using genetic variants as instruments, is an increasingly popular method of making causal inferences from observational studies. In order to design efficient Mendelian randomization studies, it is essential to calculate the sample sizes required. We present formulas for calculating the power of a Mendelian randomization study using one genetic instrument to detect an effect of a given size, and the minimum sample size required to detect effects for given levels of significance and power, using asymptotic statistical theory. We apply the formulas to some example data and compare the results with those from simulation methods. Power and sample size calculations using these formulas should be more straightforward to carry out than simulation approaches. These formulas make explicit that the sample size needed for Mendelian randomization study is inversely proportional to the square of the correlation between the genetic instrument and the exposure and proportional to the residual variance of the outcome after removing the effect of the exposure, as well as inversely proportional to the square of the effect size.

  17. Sampling versus Random Binning for Multiple Descriptions of a Bandlimited Source

    DEFF Research Database (Denmark)

    Mashiach, Adam; Østergaard, Jan; Zamir, Ram

    2013-01-01

    Random binning is an efficient, yet complex, coding technique for the symmetric L-description source coding problem. We propose an alternative approach, that uses the quantized samples of a bandlimited source as "descriptions". By the Nyquist condition, the source can be reconstructed if enough s...

  18. Recidivism among Child Sexual Abusers: Initial Results of a 13-Year Longitudinal Random Sample

    Science.gov (United States)

    Patrick, Steven; Marsh, Robert

    2009-01-01

    In the initial analysis of data from a random sample of all those charged with child sexual abuse in Idaho over a 13-year period, only one predictive variable was found that related to recidivism of those convicted. Variables such as ethnicity, relationship, gender, and age differences did not show a significant or even large association with…

  19. HABITAT ASSESSMENT USING A RANDOM PROBABILITY BASED SAMPLING DESIGN: ESCAMBIA RIVER DELTA, FLORIDA

    Science.gov (United States)

    Smith, Lisa M., Darrin D. Dantin and Steve Jordan. In press. Habitat Assessment Using a Random Probability Based Sampling Design: Escambia River Delta, Florida (Abstract). To be presented at the SWS/GERS Fall Joint Society Meeting: Communication and Collaboration: Coastal Systems...

  20. Reinforcing Sampling Distributions through a Randomization-Based Activity for Introducing ANOVA

    Science.gov (United States)

    Taylor, Laura; Doehler, Kirsten

    2015-01-01

    This paper examines the use of a randomization-based activity to introduce the ANOVA F-test to students. The two main goals of this activity are to successfully teach students to comprehend ANOVA F-tests and to increase student comprehension of sampling distributions. Four sections of students in an advanced introductory statistics course…

  1. Flexible sampling large-scale social networks by self-adjustable random walk

    Science.gov (United States)

    Xu, Xiao-Ke; Zhu, Jonathan J. H.

    2016-12-01

    Online social networks (OSNs) have become an increasingly attractive gold mine for academic and commercial researchers. However, research on OSNs faces a number of difficult challenges. One bottleneck lies in the massive quantity and often unavailability of OSN population data. Sampling perhaps becomes the only feasible solution to the problems. How to draw samples that can represent the underlying OSNs has remained a formidable task because of a number of conceptual and methodological reasons. Especially, most of the empirically-driven studies on network sampling are confined to simulated data or sub-graph data, which are fundamentally different from real and complete-graph OSNs. In the current study, we propose a flexible sampling method, called Self-Adjustable Random Walk (SARW), and test it against with the population data of a real large-scale OSN. We evaluate the strengths of the sampling method in comparison with four prevailing methods, including uniform, breadth-first search (BFS), random walk (RW), and revised RW (i.e., MHRW) sampling. We try to mix both induced-edge and external-edge information of sampled nodes together in the same sampling process. Our results show that the SARW sampling method has been able to generate unbiased samples of OSNs with maximal precision and minimal cost. The study is helpful for the practice of OSN research by providing a highly needed sampling tools, for the methodological development of large-scale network sampling by comparative evaluations of existing sampling methods, and for the theoretical understanding of human networks by highlighting discrepancies and contradictions between existing knowledge/assumptions of large-scale real OSN data.

  2. Sample size calculations for micro-randomized trials in mHealth.

    Science.gov (United States)

    Liao, Peng; Klasnja, Predrag; Tewari, Ambuj; Murphy, Susan A

    2016-05-30

    The use and development of mobile interventions are experiencing rapid growth. In "just-in-time" mobile interventions, treatments are provided via a mobile device, and they are intended to help an individual make healthy decisions 'in the moment,' and thus have a proximal, near future impact. Currently, the development of mobile interventions is proceeding at a much faster pace than that of associated data science methods. A first step toward developing data-based methods is to provide an experimental design for testing the proximal effects of these just-in-time treatments. In this paper, we propose a 'micro-randomized' trial design for this purpose. In a micro-randomized trial, treatments are sequentially randomized throughout the conduct of the study, with the result that each participant may be randomized at the 100s or 1000s of occasions at which a treatment might be provided. Further, we develop a test statistic for assessing the proximal effect of a treatment as well as an associated sample size calculator. We conduct simulation evaluations of the sample size calculator in various settings. Rules of thumb that might be used in designing a micro-randomized trial are discussed. This work is motivated by our collaboration on the HeartSteps mobile application designed to increase physical activity. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  3. Occupational position and its relation to mental distress in a random sample of Danish residents

    DEFF Research Database (Denmark)

    Rugulies, Reiner Ernst; Madsen, Ida E H; Nielsen, Maj Britt D

    2010-01-01

    somatization symptoms (OR = 6.28, 95% CI = 1.39-28.46). CONCLUSIONS: Unskilled manual workers, the unemployed, and, to a lesser extent, the low-grade self-employed showed an increased level of mental distress. Activities to promote mental health in the Danish population should be directed toward these groups.......PURPOSE: To analyze the distribution of depressive, anxiety, and somatization symptoms across different occupational positions in a random sample of Danish residents. METHODS: The study sample consisted of 591 Danish residents (50% women), aged 20-65, drawn from an age- and gender-stratified random...... sample of the Danish population. Participants filled out a survey that included the 92 item version of the Hopkins Symptom Checklist (SCL-92). We categorized occupational position into seven groups: high- and low-grade non-manual workers, skilled and unskilled manual workers, high- and low-grade self...

  4. Random sampling for a mental health survey in a deprived multi-ethnic area of Berlin.

    Science.gov (United States)

    Mundt, Adrian P; Aichberger, Marion C; Kliewe, Thomas; Ignatyev, Yuriy; Yayla, Seda; Heimann, Hannah; Schouler-Ocak, Meryam; Busch, Markus; Rapp, Michael; Heinz, Andreas; Ströhle, Andreas

    2012-12-01

    The aim of the study was to assess the response to random sampling for a mental health survey in a deprived multi-ethnic area of Berlin, Germany, with a large Turkish-speaking population. A random list from the registration office with 1,000 persons stratified by age and gender was retrieved from the population registry and these persons were contacted using a three-stage design including written information, telephone calls and personal contact at home. A female bilingual interviewer contacted persons with Turkish names. Of the persons on the list, 202 were not living in the area, one was deceased, 502 did not respond. Of the 295 responders, 152 explicitly refused(51.5%) to participate. We retained a sample of 143 participants(48.5%) representing the rate of multi-ethnicity in the area (52.1% migrants in the sample vs. 53.5% in the population). Turkish migrants were over-represented(28.9% in the sample vs. 18.6% in the population). Polish migrants (2.1 vs. 5.3% in the population) and persons from the former Yugoslavia (1.4 vs. 4.8% in the population)were under-represented. Bilingual contact procedures can improve the response rates of the most common migrant populations to random sampling if migrants of the same origin gate the contact. High non-contact and non-response rates for migrant and non-migrant populations in deprived urban areas remain a challenge for obtaining representative random samples.

  5. Assessment of proteinuria by using protein: creatinine index in random urine sample.

    Science.gov (United States)

    Khan, Dilshad Ahmed; Ahmad, Tariq Mahmood; Qureshil, Ayaz Hussain; Halim, Abdul; Ahmad, Mumtaz; Afzal, Saeed

    2005-10-01

    To assess the quantitative measurement of proteinuria by using random urine protein:creatinine index/ratio in comparison with 24 hours urinary protein excretion in patients of renal diseases having normal glomerular filtration rate. One hundred and thirty patients, 94 males and 36 females, with an age range of 5 to 60 years; having proteinuria of more than 150 mg/day were included in this study. Qualitative urinary protein estimation was done on random urine specimen by dipstick. Quantitative measurement of protein in the random and 24 hours urine specimens were carried out by a method based on the formation of a red complex of protein with pyrogallal red in acid medium on Micro lab 200 (Merck). Estimation of creatinine was done on Selectra -2 (Merck) by Jaffe's reaction. The urine protein:creatinine index and ratio were calculated by dividing the urine protein concentration (mg/L) by urine creatinine concentration (mmol/L) multilplied by 10 and mg/mg respectively. The protein:creatinine index and ratio of more than 140 and 0.18 respectively in a random urine sample indicated pathological proteinuria. An excellent correlation (r=0.96) was found between random urine protein:creatinine index/ratio and standard 24 hours urinary protein excretion in these patients (pprotein:creatinine index in random urine is a convenient, quick and reliable method of estimation of proteinuria as compared to 24 hours of urinary protein excretion for diagnosis and monitoring of renal diseases in our medical setup.

  6. Generalized essential energy space random walks to more effectively accelerate solute sampling in aqueous environment.

    Science.gov (United States)

    Lv, Chao; Zheng, Lianqing; Yang, Wei

    2012-01-28

    Molecular dynamics sampling can be enhanced via the promoting of potential energy fluctuations, for instance, based on a Hamiltonian modified with the addition of a potential-energy-dependent biasing term. To overcome the diffusion sampling issue, which reveals the fact that enlargement of event-irrelevant energy fluctuations may abolish sampling efficiency, the essential energy space random walk (EESRW) approach was proposed earlier. To more effectively accelerate the sampling of solute conformations in aqueous environment, in the current work, we generalized the EESRW method to a two-dimension-EESRW (2D-EESRW) strategy. Specifically, the essential internal energy component of a focused region and the essential interaction energy component between the focused region and the environmental region are employed to define the two-dimensional essential energy space. This proposal is motivated by the general observation that in different conformational events, the two essential energy components have distinctive interplays. Model studies on the alanine dipeptide and the aspartate-arginine peptide demonstrate sampling improvement over the original one-dimension-EESRW strategy; with the same biasing level, the present generalization allows more effective acceleration of the sampling of conformational transitions in aqueous solution. The 2D-EESRW generalization is readily extended to higher dimension schemes and employed in more advanced enhanced-sampling schemes, such as the recent orthogonal space random walk method. © 2012 American Institute of Physics

  7. Multilayer pixel super-resolution lensless in-line holographic microscope with random sample movement.

    Science.gov (United States)

    Wang, Mingjun; Feng, Shaodong; Wu, Jigang

    2017-10-06

    We report a multilayer lensless in-line holographic microscope (LIHM) with improved imaging resolution by using the pixel super-resolution technique and random sample movement. In our imaging system, a laser beam illuminated the sample and a CMOS imaging sensor located behind the sample recorded the in-line hologram for image reconstruction. During the imaging process, the sample was moved by hand randomly and the in-line holograms were acquired sequentially. Then the sample image was reconstructed from an enhanced-resolution hologram obtained from multiple low-resolution in-line holograms by applying the pixel super-resolution (PSR) technique. We studied the resolution enhancement effects by using the U.S. Air Force (USAF) target as the sample in numerical simulation and experiment. We also showed that multilayer pixel super-resolution images can be obtained by imaging a triple-layer sample made with the filamentous algae on the middle layer and microspheres with diameter of 2 μm on the top and bottom layers. Our pixel super-resolution LIHM provides a compact and low-cost solution for microscopic imaging and is promising for many biomedical applications.

  8. Randomized controlled trials 5: Determining the sample size and power for clinical trials and cohort studies.

    Science.gov (United States)

    Greene, Tom

    2015-01-01

    Performing well-powered randomized controlled trials is of fundamental importance in clinical research. The goal of sample size calculations is to assure that statistical power is acceptable while maintaining a small probability of a type I error. This chapter overviews the fundamentals of sample size calculation for standard types of outcomes for two-group studies. It considers (1) the problems of determining the size of the treatment effect that the studies will be designed to detect, (2) the modifications to sample size calculations to account for loss to follow-up and nonadherence, (3) the options when initial calculations indicate that the feasible sample size is insufficient to provide adequate power, and (4) the implication of using multiple primary endpoints. Sample size estimates for longitudinal cohort studies must take account of confounding by baseline factors.

  9. Characterization of Electron Microscopes with Binary Pseudo-random Multilayer Test Samples

    Energy Technology Data Exchange (ETDEWEB)

    V Yashchuk; R Conley; E Anderson; S Barber; N Bouet; W McKinney; P Takacs; D Voronov

    2011-12-31

    Verification of the reliability of metrology data from high quality X-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested [1] and [2] and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer [5]. Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi2/Si multilayer coating with pseudo-randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize X-ray microscopes. Corresponding work with X-ray microscopes is in progress.

  10. Characterization of electron microscopes with binary pseudo-random multilayer test samples

    Energy Technology Data Exchange (ETDEWEB)

    Yashchuk, Valeriy V., E-mail: VVYashchuk@lbl.gov [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Conley, Raymond [NSLS-II, Brookhaven National Laboratory, Upton, NY 11973 (United States); Anderson, Erik H. [Center for X-ray Optics, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Barber, Samuel K. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Bouet, Nathalie [NSLS-II, Brookhaven National Laboratory, Upton, NY 11973 (United States); McKinney, Wayne R. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Takacs, Peter Z. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Voronov, Dmitriy L. [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2011-09-01

    Verification of the reliability of metrology data from high quality X-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer [5]. Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi{sub 2}/Si multilayer coating with pseudo-randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize X-ray microscopes. Corresponding work with X-ray microscopes is in progress.

  11. The Child Behavior Checklist for Ages 1.5-5 (CBCL/1(1/2)-5): Assessment and analysis of parent- and caregiver-reported problems in a population-based sample of Danish preschool children

    DEFF Research Database (Denmark)

    Kristensen, Solvejg; Henriksen, Tine Brink; Bilenberg, Niels

    2010-01-01

    of preschool children in Denmark. Aims: The aim was to achieve Danish national norm scores for the Child Behavior Checklist for Ages 1(1/2)-5 (CBCL/1(1/2)-5) and the Caregiver Report Form (C-TRF). Methods: The study was based on an age- and gender-stratified cohort sample of 1750 children aged 1(1/2)-5 years...... for analysis of participation and representation. Results: A total number of 850 (49%) families replied, and 624 caregivers replied. The mean Total Problem Score (TPS) with 95% confidence interval was 17.3 (16.3-18.3) for parents' reports. Age-and gender-specific scale score findings for Danish preschoolers...... and schoolchildren were comparable. No differences were found in the mean TPS within subgroups related to parental socio-demographic features. Conclusion: On the basis of a large sample, Danish national norm scores and profiles of the ASEBA Preschool Forms were established; the scores of descendents must, however...

  12. Representativeness in population-based studies

    DEFF Research Database (Denmark)

    Drivsholm, Thomas Bo; Eplov, Lene Falgaard; Davidsen, Michael

    2006-01-01

    Decreasing rates of participation in population-based studies increasingly challenge the interpretation of study results, in both analytic and descriptive epidemiology. Consequently, estimates of possible differences between participants and non-participants are increasingly important...

  13. Accounting for Sampling Error in Genetic Eigenvalues Using Random Matrix Theory.

    Science.gov (United States)

    Sztepanacz, Jacqueline L; Blows, Mark W

    2017-07-01

    The distribution of genetic variance in multivariate phenotypes is characterized by the empirical spectral distribution of the eigenvalues of the genetic covariance matrix. Empirical estimates of genetic eigenvalues from random effects linear models are known to be overdispersed by sampling error, where large eigenvalues are biased upward, and small eigenvalues are biased downward. The overdispersion of the leading eigenvalues of sample covariance matrices have been demonstrated to conform to the Tracy-Widom (TW) distribution. Here we show that genetic eigenvalues estimated using restricted maximum likelihood (REML) in a multivariate random effects model with an unconstrained genetic covariance structure will also conform to the TW distribution after empirical scaling and centering. However, where estimation procedures using either REML or MCMC impose boundary constraints, the resulting genetic eigenvalues tend not be TW distributed. We show how using confidence intervals from sampling distributions of genetic eigenvalues without reference to the TW distribution is insufficient protection against mistaking sampling error as genetic variance, particularly when eigenvalues are small. By scaling such sampling distributions to the appropriate TW distribution, the critical value of the TW statistic can be used to determine if the magnitude of a genetic eigenvalue exceeds the sampling error for each eigenvalue in the spectral distribution of a given genetic covariance matrix. Copyright © 2017 by the Genetics Society of America.

  14. On analysis-based two-step interpolation methods for randomly sampled seismic data

    Science.gov (United States)

    Yang, Pengliang; Gao, Jinghuai; Chen, Wenchao

    2013-02-01

    Interpolating the missing traces of regularly or irregularly sampled seismic record is an exceedingly important issue in the geophysical community. Many modern acquisition and reconstruction methods are designed to exploit the transform domain sparsity of the few randomly recorded but informative seismic data using thresholding techniques. In this paper, to regularize randomly sampled seismic data, we introduce two accelerated, analysis-based two-step interpolation algorithms, the analysis-based FISTA (fast iterative shrinkage-thresholding algorithm) and the FPOCS (fast projection onto convex sets) algorithm from the IST (iterative shrinkage-thresholding) algorithm and the POCS (projection onto convex sets) algorithm. A MATLAB package is developed for the implementation of these thresholding-related interpolation methods. Based on this package, we compare the reconstruction performance of these algorithms, using synthetic and real seismic data. Combined with several thresholding strategies, the accelerated convergence of the proposed methods is also highlighted.

  15. An inversion method based on random sampling for real-time MEG neuroimaging

    CERN Document Server

    Pascarella, Annalisa

    2016-01-01

    The MagnetoEncephaloGraphy (MEG) has gained great interest in neurorehabilitation training due to its high temporal resolution. The challenge is to localize the active regions of the brain in a fast and accurate way. In this paper we use an inversion method based on random spatial sampling to solve the real-time MEG inverse problem. Several numerical tests on synthetic but realistic data show that the method takes just a few hundredths of a second on a laptop to produce an accurate map of the electric activity inside the brain. Moreover, it requires very little memory storage. For this reasons the random sampling method is particularly attractive in real-time MEG applications.

  16. Modified Exponential Type Estimator for Population Mean Using Auxiliary Variables in Stratified Random Sampling

    OpenAIRE

    Özel, Gamze

    2015-01-01

    In this paper, a new exponential type estimator is developed in the stratified random sampling for the population mean using auxiliary variable information. In order to evaluate efficiency of the introduced estimator, we first review some estimators and study the optimum property of the suggested strategy. To judge the merits of the suggested class of estimators over others under the optimal condition, simulation study and real data applications are conducted. The results show that the introduc...

  17. Effectiveness of hand hygiene education among a random sample of women from the community

    OpenAIRE

    Ubheeram, J.; Biranjia-Hurdoyal, S.D.

    2017-01-01

    Summary Objective. The effectiveness of hand hygiene education was investigated by studying the hand hygiene awareness and bacterial hand contamination among a random sample of 170 women in the community. Methods. Questionnaire was used to assess the hand hygiene awareness score, followed by swabbing of the dominant hand. Bacterial identification was done by conventional biochemical tests. Results. Better hand hygiene awareness score was significantly associated with age, scarce bacterial gro...

  18. Control Capacity and A Random Sampling Method in Exploring Controllability of Complex Networks

    OpenAIRE

    Jia, Tao; Barab?si, Albert-L?szl?

    2013-01-01

    Controlling complex systems is a fundamental challenge of network science. Recent advances indicate that control over the system can be achieved through a minimum driver node set (MDS). The existence of multiple MDS's suggests that nodes do not participate in control equally, prompting us to quantify their participations. Here we introduce control capacity quantifying the likelihood that a node is a driver node. To efficiently measure this quantity, we develop a random sampling algorithm. Thi...

  19. Classification of epileptic EEG signals based on simple random sampling and sequential feature selection

    OpenAIRE

    Ghayab, Hadi Ratham Al; Li, Yan; Abdulla, Shahab; Diykh, Mohammed; Wan, Xiangkui

    2016-01-01

    Electroencephalogram (EEG) signals are used broadly in the medical fields. The main applications of EEG signals are the diagnosis and treatment of diseases such as epilepsy, Alzheimer, sleep problems and so on. This paper presents a new method which extracts and selects features from multi-channel EEG signals. This research focuses on three main points. Firstly, simple random sampling (SRS) technique is used to extract features from the time domain of EEG signals. Secondly, the sequential fea...

  20. Precision of systematic and random sampling in clustered populations: habitat patches and aggregating organisms.

    Science.gov (United States)

    McGarvey, Richard; Burch, Paul; Matthews, Janet M

    2016-01-01

    Natural populations of plants and animals spatially cluster because (1) suitable habitat is patchy, and (2) within suitable habitat, individuals aggregate further into clusters of higher density. We compare the precision of random and systematic field sampling survey designs under these two processes of species clustering. Second, we evaluate the performance of 13 estimators for the variance of the sample mean from a systematic survey. Replicated simulated surveys, as counts from 100 transects, allocated either randomly or systematically within the study region, were used to estimate population density in six spatial point populations including habitat patches and Matérn circular clustered aggregations of organisms, together and in combination. The standard one-start aligned systematic survey design, a uniform 10 x 10 grid of transects, was much more precise. Variances of the 10 000 replicated systematic survey mean densities were one-third to one-fifth of those from randomly allocated transects, implying transect sample sizes giving equivalent precision by random survey would need to be three to five times larger. Organisms being restricted to patches of habitat was alone sufficient to yield this precision advantage for the systematic design. But this improved precision for systematic sampling in clustered populations is underestimated by standard variance estimators used to compute confidence intervals. True variance for the survey sample mean was computed from the variance of 10 000 simulated survey mean estimates. Testing 10 published and three newly proposed variance estimators, the two variance estimators (v) that corrected for inter-transect correlation (ν₈ and ν(W)) were the most accurate and also the most precise in clustered populations. These greatly outperformed the two "post-stratification" variance estimators (ν₂ and ν₃) that are now more commonly applied in systematic surveys. Similar variance estimator performance rankings were found with

  1. Determining optimal sample sizes for multi-stage randomized clinical trials using value of information methods.

    Science.gov (United States)

    Willan, Andrew; Kowgier, Matthew

    2008-01-01

    Traditional sample size calculations for randomized clinical trials depend on somewhat arbitrarily chosen factors, such as Type I and II errors. An effectiveness trial (otherwise known as a pragmatic trial or management trial) is essentially an effort to inform decision-making, i.e., should treatment be adopted over standard? Taking a societal perspective and using Bayesian decision theory, Willan and Pinto (Stat. Med. 2005; 24:1791-1806 and Stat. Med. 2006; 25:720) show how to determine the sample size that maximizes the expected net gain, i.e., the difference between the cost of doing the trial and the value of the information gained from the results. These methods are extended to include multi-stage adaptive designs, with a solution given for a two-stage design. The methods are applied to two examples. As demonstrated by the two examples, substantial increases in the expected net gain (ENG) can be realized by using multi-stage adaptive designs based on expected value of information methods. In addition, the expected sample size and total cost may be reduced. Exact solutions have been provided for the two-stage design. Solutions for higher-order designs may prove to be prohibitively complex and approximate solutions may be required. The use of multi-stage adaptive designs for randomized clinical trials based on expected value of sample information methods leads to substantial gains in the ENG and reductions in the expected sample size and total cost.

  2. Sample size calculations for pilot randomized trials: a confidence interval approach.

    Science.gov (United States)

    Cocks, Kim; Torgerson, David J

    2013-02-01

    To describe a method using confidence intervals (CIs) to estimate the sample size for a pilot randomized trial. Using one-sided CIs and the estimated effect size that would be sought in a large trial, we calculated the sample size needed for pilot trials. Using an 80% one-sided CI, we estimated that a pilot trial should have at least 9% of the sample size of the main planned trial. Using the estimated effect size difference for the main trial and using a one-sided CI, this allows us to calculate a sample size for a pilot trial, which will make its results more useful than at present. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Severity, not type, is the main predictor of decreased quality of life in elderly women with urinary incontinence: a population-based study as part of a randomized controlled trial in primary care

    Directory of Open Access Journals (Sweden)

    Barentsen Janka A

    2012-12-01

    Full Text Available Abstract Background Urinary incontinence negatively influences the lives of 25-50% of elderly women, mostly due to feelings of shame and being limited in activities and social interactions. This study explores whether differences exist between types of urinary incontinence (stress, urgency or mixed and severity of the symptoms, with regard to their effects on generic and condition-specific quality of life. Methods This is a cross-sectional study among participants of a randomized controlled trial in primary care. A total of 225 women (aged ≥ 55 years completed a questionnaire (on physical/emotional impact and limitations and were interviewed for demographic characteristics and co-morbidity. Least squares regression analyses were conducted to estimate differences between types and severity of urinary incontinence with regard to their effect on quality of life. Results Most patients reported mixed urinary incontinence (50.7% and a moderate severity of symptoms (48.9%. Stress urinary incontinence had a lower impact on the emotional domain of condition-specific quality of life compared with mixed urinary incontinence (r = −7.81. There were no significant associations between the types of urinary incontinence and generic quality of life. Severe symptoms affected both the generic (r = −0.10 and condition-specific (r = 17.17 quality of life. Conclusions The effects on condition-specific quality of life domains differ slightly between the types of incontinence. The level of severity affects both generic and condition-specific quality of life, indicating that it is not the type but rather the severity of urinary incontinence that is the main predictor of decreased quality of life.

  4. Acute mental disorders and short and long term morbidity in patients with third degree flame burn: A population-based outcome study of 96,451 patients from the Nationwide Inpatient Sample (NIS) database (2001-2011).

    Science.gov (United States)

    Mahendraraj, Krishnaraj; Durgan, Diane M; Chamberlain, Ronald S

    2016-12-01

    Although burn patients with preexisting mood disorders have been shown to have diminished clinical recovery, acute mental disorders (AMD) are often unrecognized despite a link with post-traumatic stress disorder and social maladjustment later on. This study assessed the clinical profile of a large cohort of burn patients who developed AMD compared to those with chronic mental illness (CMI) and those without mental health problems to assess the impact of AMI on burn outcomes. Admission data on 96,451 patients with third degree flame burns was abstracted from the Nationwide Inpatient Sample (NIS) Database from 2001 to 2011. AMD was defined as adjustment disorder (ICD-10 codes F43.2-F43.29) and acute stress disorder (F43.0), while CMI was defined as major depressive disorder (F33.0-F33.9) and bipolar disorder (F31.0-F31.9). Data was compared across three subgroups: AMD, CMI, and patients without any mood disorders. Categorical variables were compared using the Chi-square test, and continuous variables were compared using Student t-test and analysis of variance (ANOVA). Multivariate analysis using the "backward Wald" method was performed to calculate odds ratios (OR) and determine independent factors which increased the risk of developing AMD after burn. 979 (1%) burn patients were diagnosed with AMD, compared to 5971 (6.2%) with CMI and 89,501 (92.8%) without mood disorders at the time of the burn. Patients with AMD were significantly younger, predominantly male and Caucasian. Patients with AMD had a higher frequency of multiple third-degree burn sites. AMD patients had a significantly longer length of hospitalization and shorter actuarial survival. More AMD patients lacked social or family support, suffered from alcoholism or illicit drug abuse, and had a history of psychological trauma or self-inflicted injuries compared to other groups. After burn, 4.9% of AMD patients developed burn wound infections, 5.0% had nutritional deficiencies, 1.7% had skin graft failure

  5. Estimating the Size of a Large Network and its Communities from a Random Sample.

    Science.gov (United States)

    Chen, Lin; Karbasi, Amin; Crawford, Forrest W

    2016-01-01

    Most real-world networks are too large to be measured or studied directly and there is substantial interest in estimating global network properties from smaller sub-samples. One of the most important global properties is the number of vertices/nodes in the network. Estimating the number of vertices in a large network is a major challenge in computer science, epidemiology, demography, and intelligence analysis. In this paper we consider a population random graph G = (V, E) from the stochastic block model (SBM) with K communities/blocks. A sample is obtained by randomly choosing a subset W ⊆ V and letting G(W) be the induced subgraph in G of the vertices in W. In addition to G(W), we observe the total degree of each sampled vertex and its block membership. Given this partial information, we propose an efficient PopULation Size Estimation algorithm, called PULSE, that accurately estimates the size of the whole population as well as the size of each community. To support our theoretical analysis, we perform an exhaustive set of experiments to study the effects of sample size, K, and SBM model parameters on the accuracy of the estimates. The experimental results also demonstrate that PULSE significantly outperforms a widely-used method called the network scale-up estimator in a wide variety of scenarios.

  6. Nicotine therapy sampling to induce quit attempts among smokers unmotivated to quit: a randomized clinical trial.

    Science.gov (United States)

    Carpenter, Matthew J; Hughes, John R; Gray, Kevin M; Wahlquist, Amy E; Saladin, Michael E; Alberg, Anthony J

    2011-11-28

    Rates of smoking cessation have not changed in a decade, accentuating the need for novel approaches to prompt quit attempts. Within a nationwide randomized clinical trial (N = 849) to induce further quit attempts and cessation, smokers currently unmotivated to quit were randomized to a practice quit attempt (PQA) alone or to nicotine replacement therapy (hereafter referred to as nicotine therapy), sampling within the context of a PQA. Following a 6-week intervention period, participants were followed up for 6 months to assess outcomes. The PQA intervention was designed to increase motivation, confidence, and coping skills. The combination of a PQA plus nicotine therapy sampling added samples of nicotine lozenges to enhance attitudes toward pharmacotherapy and to promote the use of additional cessation resources. Primary outcomes included the incidence of any ever occurring self-defined quit attempt and 24-hour quit attempt. Secondary measures included 7-day point prevalence abstinence at any time during the study (ie, floating abstinence) and at the final follow-up assessment. Compared with PQA intervention, nicotine therapy sampling was associated with a significantly higher incidence of any quit attempt (49% vs 40%; relative risk [RR], 1.2; 95% CI, 1.1-1.4) and any 24-hour quit attempt (43% vs 34%; 1.3; 1.1-1.5). Nicotine therapy sampling was marginally more likely to promote floating abstinence (19% vs 15%; RR, 1.3; 95% CI, 1.0-1.7); 6-month point prevalence abstinence rates were no different between groups (16% vs 14%; 1.2; 0.9-1.6). Nicotine therapy sampling during a PQA represents a novel strategy to motivate smokers to make a quit attempt. clinicaltrials.gov Identifier: NCT00706979.

  7. Location and multi-depot vehicle routing for emergency vehicles using tour coverage and random sampling

    Directory of Open Access Journals (Sweden)

    Alireza Goli

    2015-09-01

    Full Text Available Distribution and optimum allocation of emergency resources are the most important tasks, which need to be accomplished during crisis. When a natural disaster such as earthquake, flood, etc. takes place, it is necessary to deliver rescue efforts as quickly as possible. Therefore, it is important to find optimum location and distribution of emergency relief resources. When a natural disaster occurs, it is not possible to reach some damaged areas. In this paper, location and multi-depot vehicle routing for emergency vehicles using tour coverage and random sampling is investigated. In this study, there is no need to visit all the places and some demand points receive their needs from the nearest possible location. The proposed study is implemented for some randomly generated numbers in different sizes. The preliminary results indicate that the proposed method was capable of reaching desirable solutions in reasonable amount of time.

  8. ESTIMATION OF FINITE POPULATION MEAN USING RANDOM NON–RESPONSE IN SURVEY SAMPLING

    Directory of Open Access Journals (Sweden)

    Housila P. Singh

    2010-12-01

    Full Text Available This paper consider the problem of estimating the population mean under three different situations of random non–response envisaged by Singh et al (2000. Some ratio and product type estimators have been proposed and their properties are studied under an assumption that the number of sampling units on which information can not be obtained owing to random non–response follows some distribution. The suggested estimators are compared with the usual ratio and product estimators. An empirical study is carried out to show the performance of the suggested estimators over usual unbiased estimator, ratio and product estimators. A generalized version of the proposed ratio and product estimators is also given.

  9. Chi-Squared Test of Fit and Sample Size-A Comparison between a Random Sample Approach and a Chi-Square Value Adjustment Method.

    Science.gov (United States)

    Bergh, Daniel

    2015-01-01

    Chi-square statistics are commonly used for tests of fit of measurement models. Chi-square is also sensitive to sample size, which is why several approaches to handle large samples in test of fit analysis have been developed. One strategy to handle the sample size problem may be to adjust the sample size in the analysis of fit. An alternative is to adopt a random sample approach. The purpose of this study was to analyze and to compare these two strategies using simulated data. Given an original sample size of 21,000, for reductions of sample sizes down to the order of 5,000 the adjusted sample size function works as good as the random sample approach. In contrast, when applying adjustments to sample sizes of lower order the adjustment function is less effective at approximating the chi-square value for an actual random sample of the relevant size. Hence, the fit is exaggerated and misfit under-estimated using the adjusted sample size function. Although there are big differences in chi-square values between the two approaches at lower sample sizes, the inferences based on the p-values may be the same.

  10. Randomized controlled trial on timing and number of sampling for bile aspiration cytology.

    Science.gov (United States)

    Tsuchiya, Tomonori; Yokoyama, Yukihiro; Ebata, Tomoki; Igami, Tsuyoshi; Sugawara, Gen; Kato, Katsuyuki; Shimoyama, Yoshie; Nagino, Masato

    2014-06-01

    The issue on timing and number of bile sampling for exfoliative bile cytology is still unsettled. A total of 100 patients with cholangiocarcinoma undergoing resection after external biliary drainage were randomized into two groups: a 2-day group where bile was sampled five times per day for 2 days; and a 10-day group where bile was sampled once per day for 10 days (registered University Hospital Medical Information Network/ID 000005983). The outcome of 87 patients who underwent laparotomy was analyzed, 44 in the 2-day group and 43 in the 10-day group. There were no significant differences in patient characteristics between the two groups. Positivity after one sampling session was significantly lower in the 2-day group than in the 10-day group (17.0 ± 3.7% vs. 20.7 ± 3.5%, P = 0.034). However, cumulative positivity curves were similar and overlapped each other between both groups. The final cumulative positivity by the 10th sampling session was 52.3% in the 2-day group and 51.2% in the 10-day group. We observed a small increase in cumulative positivity after the 5th or 6th session in both groups. Bile cytology positivity is unlikely to be affected by sample time. © 2013 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  11. Estimating the Size of a Large Network and its Communities from a Random Sample

    CERN Document Server

    Chen, Lin; Crawford, Forrest W

    2016-01-01

    Most real-world networks are too large to be measured or studied directly and there is substantial interest in estimating global network properties from smaller sub-samples. One of the most important global properties is the number of vertices/nodes in the network. Estimating the number of vertices in a large network is a major challenge in computer science, epidemiology, demography, and intelligence analysis. In this paper we consider a population random graph G = (V;E) from the stochastic block model (SBM) with K communities/blocks. A sample is obtained by randomly choosing a subset W and letting G(W) be the induced subgraph in G of the vertices in W. In addition to G(W), we observe the total degree of each sampled vertex and its block membership. Given this partial information, we propose an efficient PopULation Size Estimation algorithm, called PULSE, that correctly estimates the size of the whole population as well as the size of each community. To support our theoretical analysis, we perform an exhausti...

  12. Studies on spectral analysis of randomly sampled signals: Application to laser velocimetry data

    Science.gov (United States)

    Sree, David

    1992-01-01

    Spectral analysis is very useful in determining the frequency characteristics of many turbulent flows, for example, vortex flows, tail buffeting, and other pulsating flows. It is also used for obtaining turbulence spectra from which the time and length scales associated with the turbulence structure can be estimated. These estimates, in turn, can be helpful for validation of theoretical/numerical flow turbulence models. Laser velocimetry (LV) is being extensively used in the experimental investigation of different types of flows, because of its inherent advantages; nonintrusive probing, high frequency response, no calibration requirements, etc. Typically, the output of an individual realization laser velocimeter is a set of randomly sampled velocity data. Spectral analysis of such data requires special techniques to obtain reliable estimates of correlation and power spectral density functions that describe the flow characteristics. FORTRAN codes for obtaining the autocorrelation and power spectral density estimates using the correlation-based slotting technique were developed. Extensive studies have been conducted on simulated first-order spectrum and sine signals to improve the spectral estimates. A first-order spectrum was chosen because it represents the characteristics of a typical one-dimensional turbulence spectrum. Digital prefiltering techniques, to improve the spectral estimates from randomly sampled data were applied. Studies show that the spectral estimates can be increased up to about five times the mean sampling rate.

  13. Prevalence and correlates of problematic smartphone use in a large random sample of Chinese undergraduates.

    Science.gov (United States)

    Long, Jiang; Liu, Tie-Qiao; Liao, Yan-Hui; Qi, Chang; He, Hao-Yu; Chen, Shu-Bao; Billieux, Joël

    2016-11-17

    Smartphones are becoming a daily necessity for most undergraduates in Mainland China. Because the present scenario of problematic smartphone use (PSU) is largely unexplored, in the current study we aimed to estimate the prevalence of PSU and to screen suitable predictors for PSU among Chinese undergraduates in the framework of the stress-coping theory. A sample of 1062 undergraduate smartphone users was recruited by means of the stratified cluster random sampling strategy between April and May 2015. The Problematic Cellular Phone Use Questionnaire was used to identify PSU. We evaluated five candidate risk factors for PSU by using logistic regression analysis while controlling for demographic characteristics and specific features of smartphone use. The prevalence of PSU among Chinese undergraduates was estimated to be 21.3%. The risk factors for PSU were majoring in the humanities, high monthly income from the family (≥1500 RMB), serious emotional symptoms, high perceived stress, and perfectionism-related factors (high doubts about actions, high parental expectations). PSU among undergraduates appears to be ubiquitous and thus constitutes a public health issue in Mainland China. Although further longitudinal studies are required to test whether PSU is a transient phenomenon or a chronic and progressive condition, our study successfully identified socio-demographic and psychological risk factors for PSU. These results, obtained from a random and thus representative sample of undergraduates, opens up new avenues in terms of prevention and regulation policies.

  14. Low birthweight and neuromotor development: a population based, controlled study.

    Science.gov (United States)

    Sommerfelt, K; Ellertsen, B; Markestad, T

    1996-05-01

    The aims of the study were to investigate: (a) the relationship between low birthweight (LBW) and pre-school neuromotor development; and (b) the predictive value of various pre-, peri-, and neonatal factors for neuromotor development in LBW pre-school children. A population based sample of 144 5-year-old LBW children (birthweight neuromotor development. We conclude that motor functions essential for daily activities are intact in most LBW preschoolers.

  15. Protein/creatinine ratio on random urine samples for prediction of proteinuria in preeclampsia.

    Science.gov (United States)

    Roudsari, F Vahid; Ayati, S; Ayatollahi, H; Shakeri, M T

    2012-01-01

    To evaluate Protein/Creatinine ratio on random urine samples for prediction of proteinuria in preeclampsia. This study was performed on 150 pregnant women who were hospitalized as preeclampsia in Ghaem Hospital during 2006. At first, a 24-hours urine sample was collected for each patient to determine protein/creatinine ratio. Then, 24-hours urine collection was analyzed for the evaluation of proteinuria. Statistical analysis was performed with SPSS software. A total of 150 patients entered the study. There was a significant relation between the 24-hours urine protein and protein/creatinine ratio (r = 0.659, P < 0.001). Since the measurement of protein/creatinine ratio is more accurate, reliable, and cost-effective, it can be replaced by the method of measurement the 24-hours urine protein.

  16. Multiple Cardiometabolic Risk Factors in the Southern Cone of Latin America: A Population-based Study in Argentina, Chile, and Uruguay

    OpenAIRE

    Rubinstein, Adolfo L.; Irazola, Vilma E.; Calandrelli, Matias; Elorriaga, Natalia; Gutierrez, Laura; Lanas, Fernando; Manfredi, Jose A.; Mores, Nora; Olivera, Hector; Poggio, Rosana; Ponzo, Jacqueline; Seron, Pamela; Chen, Chung-Shiuan; Bazzano, Lydia A.; He, Jiang

    2015-01-01

    Background Cardiovascular disease is a major cause of death, and its mortality is increasing in Latin America. However, population-based data on cardiovascular disease risk factors are sparse in these countries. Methods A total of 7,524 men and women, aged 35 to 74 years old, were recruited between February 2010 and December 2011 from randomly selected samples in 4 cities (Bariloche and Marcos Paz, Argentina; Temuco, Chile; and Pando-Barros Blancos, Uruguay) in the Southern Cone of Latin Amer...

  17. LOD score exclusion analyses for candidate QTLs using random population samples.

    Science.gov (United States)

    Deng, Hong-Wen

    2003-11-01

    While extensive analyses have been conducted to test for, no formal analyses have been conducted to test against, the importance of candidate genes as putative QTLs using random population samples. Previously, we developed an LOD score exclusion mapping approach for candidate genes for complex diseases. Here, we extend this LOD score approach for exclusion analyses of candidate genes for quantitative traits. Under this approach, specific genetic effects (as reflected by heritability) and inheritance models at candidate QTLs can be analyzed and if an LOD score is < or = -2.0, the locus can be excluded from having a heritability larger than that specified. Simulations show that this approach has high power to exclude a candidate gene from having moderate genetic effects if it is not a QTL and is robust to population admixture. Our exclusion analysis complements association analysis for candidate genes as putative QTLs in random population samples. The approach is applied to test the importance of Vitamin D receptor (VDR) gene as a potential QTL underlying the variation of bone mass, an important determinant of osteoporosis.

  18. A Combined Weighting Method Based on Hybrid of Interval Evidence Fusion and Random Sampling

    Directory of Open Access Journals (Sweden)

    Ying Yan

    2017-01-01

    Full Text Available Due to the complexity of system and lack of expertise, epistemic uncertainties may present in the experts’ judgment on the importance of certain indices during group decision-making. A novel combination weighting method is proposed to solve the index weighting problem when various uncertainties are present in expert comments. Based on the idea of evidence theory, various types of uncertain evaluation information are uniformly expressed through interval evidence structures. Similarity matrix between interval evidences is constructed, and expert’s information is fused. Comment grades are quantified using the interval number, and cumulative probability function for evaluating the importance of indices is constructed based on the fused information. Finally, index weights are obtained by Monte Carlo random sampling. The method can process expert’s information with varying degrees of uncertainties, which possesses good compatibility. Difficulty in effectively fusing high-conflict group decision-making information and large information loss after fusion is avertible. Original expert judgments are retained rather objectively throughout the processing procedure. Cumulative probability function constructing and random sampling processes do not require any human intervention or judgment. It can be implemented by computer programs easily, thus having an apparent advantage in evaluation practices of fairly huge index systems.

  19. A descriptive analysis of a representative sample of pediatric randomized controlled trials published in 2007

    Directory of Open Access Journals (Sweden)

    Thomson Denise

    2010-12-01

    Full Text Available Abstract Background Randomized controlled trials (RCTs are the gold standard for trials assessing the effects of therapeutic interventions; therefore it is important to understand how they are conducted. Our objectives were to provide an overview of a representative sample of pediatric RCTs published in 2007 and assess the validity of their results. Methods We searched Cochrane Central Register of Controlled Trials using a pediatric filter and randomly selected 300 RCTs published in 2007. We extracted data on trial characteristics; outcomes; methodological quality; reporting; and registration and protocol characteristics. Trial registration and protocol availability were determined for each study based on the publication, an Internet search and an author survey. Results Most studies (83% were efficacy trials, 40% evaluated drugs, and 30% were placebo-controlled. Primary outcomes were specified in 41%; 43% reported on adverse events. At least one statistically significant outcome was reported in 77% of trials; 63% favored the treatment group. Trial registration was declared in 12% of publications and 23% were found through an Internet search. Risk of bias (ROB was high in 59% of trials, unclear in 33%, and low in 8%. Registered trials were more likely to have low ROB than non-registered trials (16% vs. 5%; p = 0.008. Effect sizes tended to be larger for trials at high vs. low ROB (0.28, 95% CI 0.21,0.35 vs. 0.16, 95% CI 0.07,0.25. Among survey respondents (50% response rate, the most common reason for trial registration was a publication requirement and for non-registration, a lack of familiarity with the process. Conclusions More than half of this random sample of pediatric RCTs published in 2007 was at high ROB and three quarters of trials were not registered. There is an urgent need to improve the design, conduct, and reporting of child health research.

  20. Inflammatory Biomarkers and Risk of Schizophrenia: A 2-Sample Mendelian Randomization Study.

    Science.gov (United States)

    Hartwig, Fernando Pires; Borges, Maria Carolina; Horta, Bernardo Lessa; Bowden, Jack; Davey Smith, George

    2017-12-01

    Positive associations between inflammatory biomarkers and risk of psychiatric disorders, including schizophrenia, have been reported in observational studies. However, conventional observational studies are prone to bias, such as reverse causation and residual confounding, thus limiting our understanding of the effect (if any) of inflammatory biomarkers on schizophrenia risk. To evaluate whether inflammatory biomarkers have an effect on the risk of developing schizophrenia. Two-sample mendelian randomization study using genetic variants associated with inflammatory biomarkers as instrumental variables to improve inference. Summary association results from large consortia of candidate gene or genome-wide association studies, including several epidemiologic studies with different designs, were used. Gene-inflammatory biomarker associations were estimated in pooled samples ranging from 1645 to more than 80 000 individuals, while gene-schizophrenia associations were estimated in more than 30 000 cases and more than 45 000 ancestry-matched controls. In most studies included in the consortia, participants were of European ancestry, and the prevalence of men was approximately 50%. All studies were conducted in adults, with a wide age range (18 to 80 years). Genetically elevated circulating levels of C-reactive protein (CRP), interleukin-1 receptor antagonist (IL-1Ra), and soluble interleukin-6 receptor (sIL-6R). Risk of developing schizophrenia. Individuals with schizophrenia or schizoaffective disorders were included as cases. Given that many studies contributed to the analyses, different diagnostic procedures were used. The pooled odds ratio estimate using 18 CRP genetic instruments was 0.90 (random effects 95% CI, 0.84-0.97; P = .005) per 2-fold increment in CRP levels; consistent results were obtained using different mendelian randomization methods and a more conservative set of instruments. The odds ratio for sIL-6R was 1.06 (95% CI, 1.01-1.12; P = .02

  1. Validation of the 2008 Landsat Burned Area Ecv Product for North America Using Stratified Random Sampling

    Science.gov (United States)

    Brunner, N. M.; Mladinich, C. S.; Caldwell, M. K.; Beal, Y. J. G.

    2014-12-01

    The U.S. Geological Survey is generating a suite of Essential Climate Variables (ECVs) products, as defined by the Global Climate Observing System, from the Landsat data archive. Validation protocols for these products are being established, incorporating the Committee on Earth Observing Satellites Land Product Validation Subgroup's best practice guidelines and validation hierarchy stages. The sampling design and accuracy measures follow the methodology developed by the European Space Agency's Climate Change Initiative Fire Disturbance (fire_cci) project (Padilla and others, 2014). A rigorous validation was performed on the 2008 Burned Area ECV (BAECV) prototype product, using a stratified random sample of 48 Thiessen scene areas overlaying Landsat path/rows distributed across several terrestrial biomes throughout North America. The validation reference data consisted of fourteen sample sites acquired from the fire_cci project and the remaining new samples sites generated from a densification of the stratified sampling for North America. The reference burned area polygons were generated using the ABAMS (Automatic Burned Area Mapping) software (Bastarrika and others, 2011; Izagirre, 2014). Accuracy results will be presented indicating strengths and weaknesses of the BAECV algorithm.Bastarrika, A., Chuvieco, E., and Martín, M.P., 2011, Mapping burned areas from Landsat TM/ETM+ data with a two-phase algorithm: Balancing omission and commission errors: Remote Sensing of Environment, v. 115, no. 4, p. 1003-1012.Izagirre, A.B., 2014, Automatic Burned Area Mapping Software (ABAMS), Preliminary Documentation, Version 10 v4,: Vitoria-Gasteiz, Spain, University of Basque Country, p. 27.Padilla, M., Chuvieco, E., Hantson, S., Theis, R., and Sandow, C., 2014, D2.1 - Product Validation Plan: UAH - University of Alcalá de Henares (Spain), 37 p.

  2. Conic sampling: an efficient method for solving linear and quadratic programming by randomly linking constraints within the interior.

    Science.gov (United States)

    Serang, Oliver

    2012-01-01

    Linear programming (LP) problems are commonly used in analysis and resource allocation, frequently surfacing as approximations to more difficult problems. Existing approaches to LP have been dominated by a small group of methods, and randomized algorithms have not enjoyed popularity in practice. This paper introduces a novel randomized method of solving LP problems by moving along the facets and within the interior of the polytope along rays randomly sampled from the polyhedral cones defined by the bounding constraints. This conic sampling method is then applied to randomly sampled LPs, and its runtime performance is shown to compare favorably to the simplex and primal affine-scaling algorithms, especially on polytopes with certain characteristics. The conic sampling method is then adapted and applied to solve a certain quadratic program, which compute a projection onto a polytope; the proposed method is shown to outperform the proprietary software Mathematica on large, sparse QP problems constructed from mass spectometry-based proteomics.

  3. Improvement of sampling strategies for randomly distributed hotspots in soil applying a computerized simulation considering the concept of uncertainty.

    Science.gov (United States)

    Hildebrandt, Thomas; Pick, Denis; Einax, Jürgen W

    2012-02-01

    The pollution of soil and environment as a result of human activity is a major problem. Nowadays, the determination of local contaminations is of interest for environmental remediation. These hotspots can have various toxic effects on plants, animals, humans, and the whole ecological system. However, economical and juridical consequences are also possible, e.g., high costs for remediation measures. In this study three sampling strategies (simple random sampling, stratified sampling, and systematic sampling) were applied on randomly distributed hotspot contaminations to prove their efficiency in term of finding hotspots. The results were used for the validation of a computerized simulation. This application can simulate the contamination on a field, the sampling pattern, and a virtual sampling. A constant hit rate showed that none of the sampling patterns could reach better results than others. Furthermore, the uncertainty associated with the results is described by confidence intervals. It is to be considered that the uncertainty during sampling is enormous and will decrease slightly, even the number of samples applied was increased to an unreasonable amount. It is hardly possible to identify the exact number of randomly distributed hotspot contaminations by statistical sampling. But a range of possible results could be calculated. Depending on various parameters such as shape and size of the area, number of hotspots, and sample quantity, optimal sampling strategies could be derived. Furthermore, an estimation of bias arising from sampling methodology is possible. The developed computerized simulation is an innovative tool for optimizing sampling strategies in terrestrial compartments for hotspot distributions.

  4. RANdom SAmple Consensus (RANSAC) algorithm for material-informatics: application to photovoltaic solar cells.

    Science.gov (United States)

    Kaspi, Omer; Yosipof, Abraham; Senderowitz, Hanoch

    2017-06-06

    An important aspect of chemoinformatics and material-informatics is the usage of machine learning algorithms to build Quantitative Structure Activity Relationship (QSAR) models. The RANdom SAmple Consensus (RANSAC) algorithm is a predictive modeling tool widely used in the image processing field for cleaning datasets from noise. RANSAC could be used as a "one stop shop" algorithm for developing and validating QSAR models, performing outlier removal, descriptors selection, model development and predictions for test set samples using applicability domain. For "future" predictions (i.e., for samples not included in the original test set) RANSAC provides a statistical estimate for the probability of obtaining reliable predictions, i.e., predictions within a pre-defined number of standard deviations from the true values. In this work we describe the first application of RNASAC in material informatics, focusing on the analysis of solar cells. We demonstrate that for three datasets representing different metal oxide (MO) based solar cell libraries RANSAC-derived models select descriptors previously shown to correlate with key photovoltaic properties and lead to good predictive statistics for these properties. These models were subsequently used to predict the properties of virtual solar cells libraries highlighting interesting dependencies of PV properties on MO compositions.

  5. Epidemiology of maternal injuries during pregnancy in a population-based study, 1997-2005.

    Science.gov (United States)

    Tinker, Sarah C; Reefhuis, Jennita; Dellinger, Ann M; Jamieson, Denise J

    2010-12-01

    Maternal injuries during pregnancy are common and can cause adverse pregnancy outcomes. We sought to describe factors related to injury during pregnancy. We analyzed data from the National Birth Defects Prevention Study (NBDPS), a population-based, case-control study of birth defects in 10 U.S. states. We estimated the proportion of control mothers, a random sample of mothers delivering infants without major birth defects in the study regions, who reported an injury during pregnancy. We assessed associations with maternal and paternal characteristics using logistic regression to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI). Between October 1997 and December 2005, 490 (7.4%) of 6609 mothers reported 527 injuries during pregnancy. Falls caused over half of reported injuries during pregnancy (51.6%), and 9.5% of reported injuries were intentionally inflicted. Mothers who reported an injury during pregnancy were more likely to be aged injuries during pregnancy.

  6. Sample size and power for a stratified doubly randomized preference design.

    Science.gov (United States)

    Cameron, Briana; Esserman, Denise A

    2016-11-21

    The two-stage (or doubly) randomized preference trial design is an important tool for researchers seeking to disentangle the role of patient treatment preference on treatment response through estimation of selection and preference effects. Up until now, these designs have been limited by their assumption of equal preference rates and effect sizes across the entire study population. We propose a stratified two-stage randomized trial design that addresses this limitation. We begin by deriving stratified test statistics for the treatment, preference, and selection effects. Next, we develop a sample size formula for the number of patients required to detect each effect. The properties of the model and the efficiency of the design are established using a series of simulation studies. We demonstrate the applicability of the design using a study of Hepatitis C treatment modality, specialty clinic versus mobile medical clinic. In this example, a stratified preference design (stratified by alcohol/drug use) may more closely capture the true distribution of patient preferences and allow for a more efficient design than a design which ignores these differences (unstratified version). © The Author(s) 2016.

  7. Notes on interval estimation of the generalized odds ratio under stratified random sampling.

    Science.gov (United States)

    Lui, Kung-Jong; Chang, Kuang-Chao

    2013-05-01

    It is not rare to encounter the patient response on the ordinal scale in a randomized clinical trial (RCT). Under the assumption that the generalized odds ratio (GOR) is homogeneous across strata, we consider four asymptotic interval estimators for the GOR under stratified random sampling. These include the interval estimator using the weighted-least-squares (WLS) approach with the logarithmic transformation (WLSL), the interval estimator using the Mantel-Haenszel (MH) type of estimator with the logarithmic transformation (MHL), the interval estimator using Fieller's theorem with the MH weights (FTMH) and the interval estimator using Fieller's theorem with the WLS weights (FTWLS). We employ Monte Carlo simulation to evaluate the performance of these interval estimators by calculating the coverage probability and the average length. To study the bias of these interval estimators, we also calculate and compare the noncoverage probabilities in the two tails of the resulting confidence intervals. We find that WLSL and MHL can generally perform well, while FTMH and FTWLS can lose either precision or accuracy. We further find that MHL is likely the least biased. Finally, we use the data taken from a study of smoking status and breathing test among workers in certain industrial plants in Houston, Texas, during 1974 to 1975 to illustrate the use of these interval estimators.

  8. Control capacity and a random sampling method in exploring controllability of complex networks.

    Science.gov (United States)

    Jia, Tao; Barabási, Albert-László

    2013-01-01

    Controlling complex systems is a fundamental challenge of network science. Recent advances indicate that control over the system can be achieved through a minimum driver node set (MDS). The existence of multiple MDS's suggests that nodes do not participate in control equally, prompting us to quantify their participations. Here we introduce control capacity quantifying the likelihood that a node is a driver node. To efficiently measure this quantity, we develop a random sampling algorithm. This algorithm not only provides a statistical estimate of the control capacity, but also bridges the gap between multiple microscopic control configurations and macroscopic properties of the network under control. We demonstrate that the possibility of being a driver node decreases with a node's in-degree and is independent of its out-degree. Given the inherent multiplicity of MDS's, our findings offer tools to explore control in various complex systems.

  9. Classification of epileptic EEG signals based on simple random sampling and sequential feature selection.

    Science.gov (United States)

    Ghayab, Hadi Ratham Al; Li, Yan; Abdulla, Shahab; Diykh, Mohammed; Wan, Xiangkui

    2016-06-01

    Electroencephalogram (EEG) signals are used broadly in the medical fields. The main applications of EEG signals are the diagnosis and treatment of diseases such as epilepsy, Alzheimer, sleep problems and so on. This paper presents a new method which extracts and selects features from multi-channel EEG signals. This research focuses on three main points. Firstly, simple random sampling (SRS) technique is used to extract features from the time domain of EEG signals. Secondly, the sequential feature selection (SFS) algorithm is applied to select the key features and to reduce the dimensionality of the data. Finally, the selected features are forwarded to a least square support vector machine (LS_SVM) classifier to classify the EEG signals. The LS_SVM classifier classified the features which are extracted and selected from the SRS and the SFS. The experimental results show that the method achieves 99.90, 99.80 and 100 % for classification accuracy, sensitivity and specificity, respectively.

  10. Association between alcohol consumption and systolic ventricular function: a population-based study.

    Science.gov (United States)

    Yousaf, Haroon; Rodeheffer, Richard J; Paterick, Timothy E; Ashary, Zain; Ahmad, Mirza Nubair; Ammar, Khawaja Afzal

    2014-06-01

    Although moderate alcohol consumption is associated with decreased clinical heart failure, there are no population-based studies evaluating the relationship between alcohol consumption and left ventricular (LV) systolic function. We sought to evaluate the relationship between alcohol consumption and LV systolic function in the community. In a population-based random sample of 2,042 adults, age ≥45 years, we assessed alcohol consumption by a self-administered questionnaire. Responders were categorized by alcohol consumption level: abstainer, former drinker, light drinker (2 drinks a day). Systolic function was assessed by echocardiography. We identified 38 cases of systolic dysfunction in 182 abstainers, 309 former drinkers, 1,028 light drinkers, 251 moderate drinkers, and 146 heavy drinkers. A U-shaped relationship was observed between alcohol consumption and moderate systolic dysfunction (LV ejection fraction [LVEF] ≤40%), with the lowest prevalence in light drinkers (0.9%) compared to the highest prevalence in heavy drinkers (5.5%) (odds ratio 0.14, 95% CI 0.04-0.43). This association persisted across different strata of risk factors of systolic dysfunction as well as in multivariate analysis. No significant association between alcohol consumption and systolic function was seen in subjects with LVEF >50% or ≤50%. There is a U-shaped relationship between alcohol consumption volume and LVEF, with the lowest risk of moderate LV dysfunction (LVEF ≤40%) observed in light drinkers (consumption and cardiovascular disease prevalence. Copyright © 2014 Mosby, Inc. All rights reserved.

  11. High prevalence of undiagnosed coeliac disease in adults: a Swedish population-based study.

    Science.gov (United States)

    Ivarsson, A; Persson, L A; Juto, P; Peltonen, M; Suhr, O; Hernell, O

    1999-01-01

    To determine the prevalence of coeliac disease in a population-based sample of Swedish adults. Population-based cross-sectional study. Northern Sweden. A total of 1894 adults (76%) out of 2500 invited, randomly selected from the population register after stratification for age and sex. Prevalence of biopsy verified coeliac disease, symptoms of undiagnosed cases, and results of antiendomysium and antigliadin serum antibody tests. Coeliac disease was confirmed by intestinal biopsy showing enteropathy in 10 individuals (seven women and three men), corresponding to a prevalence of 5.3 per 1000 (95% CI = 2.5-9.7). The majority of cases (eight out of 10) had not been diagnosed prior to the screening, although many had symptoms compatible with coeliac disease. All individuals with antiendomysium antibody positivity who were subjected to a small intestinal biopsy had enteropathy. Furthermore, all of them also had elevated levels of antigliadin antibodies type IgA and/or IgG. Coeliac disease is common, albeit mostly undiagnosed, in Swedish adults. It is likely that the situation is no better in other countries. This highlights the importance of keeping coeliac disease in mind, and of promptly investigating individuals with unexplained, even mild, symptoms compatible with the disease. Serological markers, e.g. antigliadin and antiendomysium antibodies, are useful tools within this active case-finding strategy, although the final diagnosis should be based on an intestinal biopsy demonstrating enteropathy.

  12. Randomized Controlled Trial of Attention Bias Modification in a Racially Diverse, Socially Anxious, Alcohol Dependent Sample

    Science.gov (United States)

    Clerkin, Elise M.; Magee, Joshua C.; Wells, Tony T.; Beard, Courtney; Barnett, Nancy P.

    2016-01-01

    Objective Attention biases may be an important treatment target for both alcohol dependence and social anxiety. This is the first ABM trial to investigate two (vs. one) targets of attention bias within a sample with co-occurring symptoms of social anxiety and alcohol dependence. Additionally, we used trial-level bias scores (TL-BS) to capture the phenomena of attention bias in a more ecologically valid, dynamic way compared to traditional attention bias scores. Method Adult participants (N=86; 41% Female; 52% African American; 40% White) with elevated social anxiety symptoms and alcohol dependence were randomly assigned to an 8-session training condition in this 2 (Social Anxiety ABM vs. Social Anxiety Control) by 2 (Alcohol ABM vs. Alcohol Control) design. Symptoms of social anxiety, alcohol dependence, and attention bias were assessed across time. Results Multilevel models estimated the trajectories for each measure within individuals, and tested whether these trajectories differed according to the randomized training conditions. Across time, there were significant or trending decreases in all attention TL-BS parameters (but not traditional attention bias scores) and most symptom measures. However, there were not significant differences in the trajectories of change between any ABM and control conditions for any symptom measures. Conclusions These findings add to previous evidence questioning the robustness of ABM and point to the need to extend the effects of ABM to samples that are racially diverse and/or have co-occurring psychopathology. The results also illustrate the potential importance of calculating trial-level attention bias scores rather than only including traditional bias scores. PMID:27591918

  13. Random sampling or geostatistical modelling? Choosing between design-based and model-based sampling strategies for soil (with discussion)

    NARCIS (Netherlands)

    Brus, D.J.; Gruijter, de J.J.

    1997-01-01

    Classical sampling theory has been repeatedly identified with classical statistics which assumes that data are identically and independently distributed. This explains the switch of many soil scientists from design-based sampling strategies, based on classical sampling theory, to the model-based

  14. Random Photon Absorption Model Elucidates How Early Gain Control in Fly Photoreceptors Arises from Quantal Sampling

    Science.gov (United States)

    Song, Zhuoyi; Zhou, Yu; Juusola, Mikko

    2016-01-01

    Many diurnal photoreceptors encode vast real-world light changes effectively, but how this performance originates from photon sampling is unclear. A 4-module biophysically-realistic fly photoreceptor model, in which information capture is limited by the number of its sampling units (microvilli) and their photon-hit recovery time (refractoriness), can accurately simulate real recordings and their information content. However, sublinear summation in quantum bump production (quantum-gain-nonlinearity) may also cause adaptation by reducing the bump/photon gain when multiple photons hit the same microvillus simultaneously. Here, we use a Random Photon Absorption Model (RandPAM), which is the 1st module of the 4-module fly photoreceptor model, to quantify the contribution of quantum-gain-nonlinearity in light adaptation. We show how quantum-gain-nonlinearity already results from photon sampling alone. In the extreme case, when two or more simultaneous photon-hits reduce to a single sublinear value, quantum-gain-nonlinearity is preset before the phototransduction reactions adapt the quantum bump waveform. However, the contribution of quantum-gain-nonlinearity in light adaptation depends upon the likelihood of multi-photon-hits, which is strictly determined by the number of microvilli and light intensity. Specifically, its contribution to light-adaptation is marginal (≤ 1%) in fly photoreceptors with many thousands of microvilli, because the probability of simultaneous multi-photon-hits on any one microvillus is low even during daylight conditions. However, in cells with fewer sampling units, the impact of quantum-gain-nonlinearity increases with brightening light. PMID:27445779

  15. Notes on interval estimation of the gamma correlation under stratified random sampling.

    Science.gov (United States)

    Lui, Kung-Jong; Chang, Kuang-Chao

    2012-07-01

    We have developed four asymptotic interval estimators in closed forms for the gamma correlation under stratified random sampling, including the confidence interval based on the most commonly used weighted-least-squares (WLS) approach (CIWLS), the confidence interval calculated from the Mantel-Haenszel (MH) type estimator with the Fisher-type transformation (CIMHT), the confidence interval using the fundamental idea of Fieller's Theorem (CIFT) and the confidence interval derived from a monotonic function of the WLS estimator of Agresti's α with the logarithmic transformation (MWLSLR). To evaluate the finite-sample performance of these four interval estimators and note the possible loss of accuracy in application of both Wald's confidence interval and MWLSLR using pooled data without accounting for stratification, we employ Monte Carlo simulation. We use the data taken from a general social survey studying the association between the income level and job satisfaction with strata formed by genders in black Americans published elsewhere to illustrate the practical use of these interval estimators. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Predictive value of testing random urine sample to detect microalbuminuria in diabetic subjects during outpatient visit.

    Science.gov (United States)

    Bouhanick, B; Berrut, G; Chameau, A M; Hallar, M; Bled, F; Chevet, B; Vergely, J; Rohmer, V; Fressinaud, P; Marre, M

    1992-01-01

    The predictive value of random urine sample during outpatient visit to predict persistent microalbuminuria was studied in 76 Type 1, insulin-dependent diabetic subjects, 61 Type 2, non-insulin-dependent diabetic subjects, and 72 Type 2, insulin-treated diabetic subjects. Seventy-six patients attended outpatient clinic during morning, and 133 during afternoon. Microalbuminuria was suspected if Urinary Albumin Excretion (UAE) exceeded 20 mg/l. All patients were hospitalized within 6 months following outpatient visit, and persistent microalbuminuria was assessed then if UAE was between 30 and 300 mg/24 h on 2-3 occasions in 3 urines samples. Of these 209 subjects eighty-three were also screened with Microbumintest (Ames-Bayer), a semi-quantitative method. Among the 209 subjects, 71 were positive both for microalbuminuria during outpatient visit and a persistent microalbuminuria during hospitalization: sensitivity 91.0%, specificity 83.2%, concordance 86.1%, and positive predictive value 76.3% (chi-squared test: 191; p less than 10(-4)). Data were not different for subjects examined on morning, or on afternoon. Among the 83 subjects also screened with Microbumintest, 22 displayed both a positive reaction and a persistent microalbuminuria: sensitivity 76%, specificity 81%, concordance 80%, and positive predictive value 69% (chi-squared test: 126; p less than 10(-4)). Both types of screening appeared equally effective during outpatient visit. Hence, a persistent microalbuminuria can be predicted during an outpatient visit in a diabetic clinic.

  17. Effectiveness of hand hygiene education among a random sample of women from the community.

    Science.gov (United States)

    Ubheeram, J; Biranjia-Hurdoyal, S D

    2017-03-01

    The effectiveness of hand hygiene education was investigated by studying the hand hygiene awareness and bacterial hand contamination among a random sample of 170 women in the community. Questionnaire was used to assess the hand hygiene awareness score, followed by swabbing of the dominant hand. Bacterial identification was done by conventional biochemical tests. Better hand hygiene awareness score was significantly associated with age, scarce bacterial growth and absence of potential pathogen (p hand samples, bacterial growth was noted in 155 (91.2%), which included 91 (53.5%) heavy growth, 53 (31.2%) moderate growth and 11 (6.47%) scanty growth. The presence of enteric bacteria was associated with long nails (49.4% vs 29.2%; p = 0.007; OR = 2.3; 95% CI: 1.25-4.44) while finger rings were associated with higher bacterial load (p = 0.003). Coliforms was significantly higher among women who had a lower hand hygiene awareness score, washed their hands at lower frequency (59.0% vs 32.8%; p = 0.003; OR = 2.9; 95% CI: 1.41-6.13) and used common soap as compared to antiseptic soaps (69.7% vs 30.3%, p = 0.000; OR = 4.11; 95% CI: 1.67-10.12). Level of hand hygiene awareness among the participants was satisfactory but not the compliance of hand washing practice, especially among the elders.

  18. Association between stalking victimisation and psychiatric morbidity in a random community sample.

    Science.gov (United States)

    Purcell, Rosemary; Pathé, Michele; Mullen, Paul E

    2005-11-01

    No studies have assessed psychopathology among victims of stalking who have not sought specialist help. To examine the associations between stalking victimisation and psychiatric morbidity in a representative community sample. A random community sample (n=1844) completed surveys examining the experience of harassment and current mental health. The 28-item General Health Questionnaire (GHQ-28) and the Impact of Event Scale were used to assess symptomatology in those reporting brief harassment (n=196) or protracted stalking (n=236) and a matched control group reporting no harassment (n=432). Rates of caseness on the GHQ-28 were higher among stalking victims (36.4%) than among controls (19.3%) and victims of brief harassment (21.9%). Psychiatric morbidity did not differ according to the recency of victimisation, with 34.1% of victims meeting caseness criteria 1 year after stalking had ended. In a significant minority of victims, stalking victimisation is associated with psychiatric morbidity that may persist long after it has ceased. Recognition of the immediate and long-term impacts of stalking is necessary to assist victims and help alleviate distress and long-term disability.

  19. Random sample community-based health surveys: does the effort to reach participants matter?

    Science.gov (United States)

    Messiah, Antoine; Castro, Grettel; Rodríguez de la Vega, Pura; Acuna, Juan M

    2014-12-15

    Conducting health surveys with community-based random samples are essential to capture an otherwise unreachable population, but these surveys can be biased if the effort to reach participants is insufficient. This study determines the desirable amount of effort to minimise such bias. A household-based health survey with random sampling and face-to-face interviews. Up to 11 visits, organised by canvassing rounds, were made to obtain an interview. Single-family homes in an underserved and understudied population in North Miami-Dade County, Florida, USA. Of a probabilistic sample of 2200 household addresses, 30 corresponded to empty lots, 74 were abandoned houses, 625 households declined to participate and 265 could not be reached and interviewed within 11 attempts. Analyses were performed on the 1206 remaining households. Each household was asked if any of their members had been told by a doctor that they had high blood pressure, heart disease including heart attack, cancer, diabetes, anxiety/ depression, obesity or asthma. Responses to these questions were analysed by the number of visit attempts needed to obtain the interview. Return per visit fell below 10% after four attempts, below 5% after six attempts and below 2% after eight attempts. As the effort increased, household size decreased, while household income and the percentage of interviewees active and employed increased; proportion of the seven health conditions decreased, four of which did so significantly: heart disease 20.4-9.2%, high blood pressure 63.5-58.1%, anxiety/depression 24.4-9.2% and obesity 21.8-12.6%. Beyond the fifth attempt, however, cumulative percentages varied by less than 1% and precision varied by less than 0.1%. In spite of the early and steep drop, sustaining at least five attempts to reach participants is necessary to reduce selection bias. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  20. Sample-to-sample fluctuations of power spectrum of a random motion in a periodic Sinai model

    Science.gov (United States)

    Dean, David S.; Iorio, Antonio; Marinari, Enzo; Oshanin, Gleb

    2016-09-01

    The Sinai model of a tracer diffusing in a quenched Brownian potential is a much-studied problem exhibiting a logarithmically slow anomalous diffusion due to the growth of energy barriers with the system size. However, if the potential is random but periodic, the regime of anomalous diffusion crosses over to one of normal diffusion once a tracer has diffused over a few periods of the system. Here we consider a system in which the potential is given by a Brownian bridge on a finite interval (0 ,L ) and then periodically repeated over the whole real line and study the power spectrum S (f ) of the diffusive process x (t ) in such a potential. We show that for most of realizations of x (t ) in a given realization of the potential, the low-frequency behavior is S (f ) ˜A /f2 , i.e., the same as for standard Brownian motion, and the amplitude A is a disorder-dependent random variable with a finite support. Focusing on the statistical properties of this random variable, we determine the moments of A of arbitrary, negative, or positive order k and demonstrate that they exhibit a multifractal dependence on k and a rather unusual dependence on the temperature and on the periodicity L , which are supported by atypical realizations of the periodic disorder. We finally show that the distribution of A has a log-normal left tail and exhibits an essential singularity close to the right edge of the support, which is related to the Lifshitz singularity. Our findings are based both on analytic results and on extensive numerical simulations of the process x (t ) .

  1. Random Model Sampling: Making Craig Interpolation Work When It Should Not

    Directory of Open Access Journals (Sweden)

    Marat Akhin

    2014-01-01

    Full Text Available One of the most serious problems when doing program analyses is dealing with function calls. While function inlining is the traditional approach to this problem, it nonetheless suffers from the increase in analysis complexity due to the state space explosion. Craig interpolation has been successfully used in recent years in the context of bounded model checking to do function summarization which allows one to replace the complete function body with its succinct summary and, therefore, reduce the complexity. Unfortunately this technique can be applied only to a pair of unsatisfiable formulae.In this work-in-progress paper we present an approach to function summarization based on Craig interpolation that overcomes its limitation by using random model sampling. It captures interesting input/output relations, strengthening satisfiable formulae into unsatisfiable ones and thus allowing the use of Craig interpolation. Preliminary experiments show the applicability of this approach; in our future work we plan to do a full evaluation on real-world examples.

  2. Discriminative motif discovery via simulated evolution and random under-sampling.

    Directory of Open Access Journals (Sweden)

    Tao Song

    Full Text Available Conserved motifs in biological sequences are closely related to their structure and functions. Recently, discriminative motif discovery methods have attracted more and more attention. However, little attention has been devoted to the data imbalance problem, which is one of the main reasons affecting the performance of the discriminative models. In this article, a simulated evolution method is applied to solve the multi-class imbalance problem at the stage of data preprocessing, and at the stage of Hidden Markov Models (HMMs training, a random under-sampling method is introduced for the imbalance between the positive and negative datasets. It is shown that, in the task of discovering targeting motifs of nine subcellular compartments, the motifs found by our method are more conserved than the methods without considering data imbalance problem and recover the most known targeting motifs from Minimotif Miner and InterPro. Meanwhile, we use the found motifs to predict protein subcellular localization and achieve higher prediction precision and recall for the minority classes.

  3. Neurofeedback Against Binge Eating: A Randomized Controlled Trial in a Female Subclinical Threshold Sample.

    Science.gov (United States)

    Schmidt, Jennifer; Martin, Alexandra

    2016-09-01

    Brain-directed treatment techniques, such as neurofeedback, have recently been proposed as adjuncts in the treatment of eating disorders to improve therapeutic outcomes. In line with this recommendation, a cue exposure EEG-neurofeedback protocol was developed. The present study aimed at the evaluation of the specific efficacy of neurofeedback to reduce subjective binge eating in a female subthreshold sample. A total of 75 subjects were randomized to EEG-neurofeedback, mental imagery with a comparable treatment set-up or a waitlist group. At post-treatment, only EEG-neurofeedback led to a reduced frequency of binge eating (p = .015, g = 0.65). The effects remained stable to a 3-month follow-up. EEG-neurofeedback further showed particular beneficial effects on perceived stress and dietary self-efficacy. Differences in outcomes did not arise from divergent treatment expectations. Because EEG-neurofeedback showed a specific efficacy, it may be a promising brain-directed approach that should be tested as a treatment adjunct in clinical groups with binge eating. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.

  4. A coupled well-balanced and random sampling scheme for computing bubble oscillations*

    Directory of Open Access Journals (Sweden)

    Jung Jonathan

    2012-04-01

    Full Text Available We propose a finite volume scheme to study the oscillations of a spherical bubble of gas in a liquid phase. Spherical symmetry implies a geometric source term in the Euler equations. Our scheme satisfies the well-balanced property. It is based on the VFRoe approach. In order to avoid spurious pressure oscillations, the well-balanced approach is coupled with an ALE (Arbitrary Lagrangian Eulerian technique at the interface and a random sampling remap. Nous proposons un schéma de volumes finis pour étudier les oscillations d’une bulle sphérique de gaz dans l’eau. La symétrie sphérique fait apparaitre un terme source géométrique dans les équations d’Euler. Notre schéma est basé sur une approche VFRoe et préserve les états stationnaires. Pour éviter les oscillations de pression, l’approche well-balanced est couplée avec une approche ALE (Arbitrary Lagrangian Eulerian, et une étape de projection basée sur un échantillonage aléatoire.

  5. Comparing cluster-level dynamic treatment regimens using sequential, multiple assignment, randomized trials: Regression estimation and sample size considerations.

    Science.gov (United States)

    NeCamp, Timothy; Kilbourne, Amy; Almirall, Daniel

    2017-08-01

    Cluster-level dynamic treatment regimens can be used to guide sequential treatment decision-making at the cluster level in order to improve outcomes at the individual or patient-level. In a cluster-level dynamic treatment regimen, the treatment is potentially adapted and re-adapted over time based on changes in the cluster that could be impacted by prior intervention, including aggregate measures of the individuals or patients that compose it. Cluster-randomized sequential multiple assignment randomized trials can be used to answer multiple open questions preventing scientists from developing high-quality cluster-level dynamic treatment regimens. In a cluster-randomized sequential multiple assignment randomized trial, sequential randomizations occur at the cluster level and outcomes are observed at the individual level. This manuscript makes two contributions to the design and analysis of cluster-randomized sequential multiple assignment randomized trials. First, a weighted least squares regression approach is proposed for comparing the mean of a patient-level outcome between the cluster-level dynamic treatment regimens embedded in a sequential multiple assignment randomized trial. The regression approach facilitates the use of baseline covariates which is often critical in the analysis of cluster-level trials. Second, sample size calculators are derived for two common cluster-randomized sequential multiple assignment randomized trial designs for use when the primary aim is a between-dynamic treatment regimen comparison of the mean of a continuous patient-level outcome. The methods are motivated by the Adaptive Implementation of Effective Programs Trial which is, to our knowledge, the first-ever cluster-randomized sequential multiple assignment randomized trial in psychiatry.

  6. Investigação de disfunção miccional em uma amostra populacional de crianças de 3 a 9 anos Investigation of voiding dysfunction in a population-based sample of children aged 3 to 9 years

    Directory of Open Access Journals (Sweden)

    Denise M. Mota

    2005-06-01

    Full Text Available OBJETIVO: Descrever os hábitos miccionais e suas disfunções em uma amostra populacional de crianças de 3 a 9 anos. MÉTODOS: Delineamento transversal, incluindo 580 crianças. Uma amostra probabilística de domicílios da zona urbana da cidade de Pelotas (RS foi selecionada em múltiplos estágios. Os hábitos miccionais e fecais foram avaliados com o escore de disfunção miccional proposto por Farhat et al. e modificado pela equipe de pesquisa com acréscimo do sintoma freqüência urinária superior a oito vezes ao dia. Os meninos com pontuação maior que oito e as meninas com pontuação maior que cinco foram reavaliados clinicamente, assim como uma subamostra dos demais. RESULTADOS: Os sintomas miccionais mais freqüentes foram noctúria (60,4%, urgência miccional (49,7% e manobras de contenção (42,1%. A prevalência de enurese foi de 20,1% em meninos e 15,1% em meninas. A prevalência de disfunção miccional pelo escore Farhat et al. foi de 24,2%. A maioria dos sintomas foi mais freqüente entre as meninas e entre crianças mais jovens. As meninas de nível econômico baixo apresentaram maior freqüência de enurese e força para urinar, enquanto que, entre os meninos, a urgência miccional foi mais comum entre os mais pobres. Apenas 10,5% dos pais de crianças com disfunção haviam levado seu filho ao médico por causa dos sintomas. CONCLUSÕES: Os sintomas miccionais apresentam prevalências altas e devem ser investigados ativamente nas consultas de rotina, com perguntas diretas sobre cada sintoma isoladamente, objetivando o diagnóstico de disfunção miccional.OBJECTIVE: To describe voiding patterns and related dysfunctions in a population-based sample of children aged 3 to 9 years. METHODS: A cross-sectional population-based survey including 580 children. A probabilistic sample of households in the urban area of Pelotas in southern Brazil was selected following a multiple-stage protocol. Voiding and fecal patterns were

  7. Population-Based Study of Trachoma in Guatemala.

    Science.gov (United States)

    Silva, Juan Carlos; Diaz, Marco Antonio; Maul, Eugenio; Munoz, Beatriz E; West, Sheila K

    2015-01-01

    A prevalence survey for active trachoma in children aged under 10 years and trichiasis in women aged 40 years and older was carried out in four districts in the Sololá region in Guatemala, which is suspected of still having a trachoma problem. Population-based surveys were undertaken in three districts, within 15 randomly selected communities in each district. In addition, in a fourth district that borders the third district chosen, we surveyed the small northern sub-district, by randomly selecting three communities in each community, 100 children aged under 10 years were randomly selected, and all females over 40 years. Five survey teams were trained and standardized. Trachoma was graded using the World Health Organization simplified grading scheme and ocular swabs were taken in cases of clinical follicular or inflammatory trachoma. Prevalence estimates were calculated at district and sub-district level. Trachoma rates at district level varied from 0-5.1%. There were only two sub-districts where active trachoma approached 10% (Nahualá Costa, 8.1%, and Santa Catarina Costa, 7.3%). Trichiasis rates in females aged 40 years and older varied from 0-3%. Trachoma was likely a problem in the past. Trachoma is disappearing in the Sololá region in Guatemala. Health leadership may consider further mapping of villages around the areas with an especially high rate of trachoma and infection, and instituting trichiasis surgery and active trachoma intervention where needed.

  8. A population-based cohort study of oral health in South Brazil : the Porto Alegre study

    OpenAIRE

    Haas, Alex Nogueira; GAIO,Eduardo José; Wagner, Marcius Comparsi; Rios, Fernando Silva; Costa,Ricardo dos Santos Araujo; Rösing, Cassiano Kuchenbecker; Oppermann, Rui Vicente; Albandar, Jasim M.; Susin, Cristiano

    2015-01-01

    Few population-based cohort studies have been established in Dentistry and this is especially true for Latin America. We conducted a population-based prospective study focusing on oral health in Porto Alegre, south Brazil, and herein we describe its methodology and discuss directions for further research. The cohort was established in 2001 using a multistage probability sample of 1,465 toothed and 121 edentulous subjects. A 5-year follow-up was performed in 2006 that included 755 individuals....

  9. A population-based cohort study of oral health in South Brazil: The Porto Alegre Study

    OpenAIRE

    Alex Nogueira Haas; Eduardo José Gaio; Marcius Comparsi Wagner; Fernando Silva Rios; Ricardo dos Santos Araujo Costa; Cassiano Kuchenbecker Rösing; Rui Vicente Oppermann; Jasim Albandar; Cristiano Susin

    2015-01-01

    Few population-based cohort studies have been established in Dentistry and this is especially true for Latin America. We conducted a population-based prospective study focusing on oral health in Porto Alegre, south Brazil, and herein we describe its methodology and discuss directions for further research. The cohort was established in 2001 using a multistage probability sample of 1,465 toothed and 121 edentulous subjects. A 5-year follow-up was performed in 2006 that included 755 individuals....

  10. Mutual associations between intellectual disability and epilepsy-related psychiatry disability: Population-based study.

    Science.gov (United States)

    Wang, Zhenjie; Guo, Chao; Chen, Gong; Zhang, Lei; Wen, Xun; Zheng, Xiaoying

    2017-05-01

    Epilepsy is the third-leading cause of psychiatry disability in China, and intellectual disability (ID) is also 1 major type of disabilities in China. This study estimates the prevalence of comorbidities with ID and epilepsy-related psychiatry disability (EPD) and examines mutual associations within ID and EPD.Data were taken from the Second China National Sample Survey on Disability, which was a nationally representative, population-based survey. To derive a nationally representative sample, the survey used multistage, stratified, cluster random sampling with probability proportional to size. The disabled people who had ID and EPD based on the World Health Organization International Classification of Functioning, Disability, and Health and the International Statistical Classification of Diseases. The cox-proportional hazards model was used to examine the associations between ID and EPD considering the happened sequence of ID and EPD.The prevalence of ID with EPD was 0.14 (95% confidence interval: 0.09-0.19) per 1000 people. Age was strongly associated with the risk of EPD, which was diagnosed after ID, especially among young ID population. Except for age, other variables were also associated between ID and EPD considering sequence of ID and EPD.This study is the first national study to explore mutual associations with ID and EPD and highlights the young ID children with high risk of development of epilepsy. To address the challenge of ID with EPD disability in China, the government should adjust its strategies for healthcare systems to prevent disability.

  11. Experiments with central-limit properties of spatial samples from locally covariant random fields

    Science.gov (United States)

    Barringer, T.H.; Smith, T.E.

    1992-01-01

    When spatial samples are statistically dependent, the classical estimator of sample-mean standard deviation is well known to be inconsistent. For locally dependent samples, however, consistent estimators of sample-mean standard deviation can be constructed. The present paper investigates the sampling properties of one such estimator, designated as the tau estimator of sample-mean standard deviation. In particular, the asymptotic normality properties of standardized sample means based on tau estimators are studied in terms of computer experiments with simulated sample-mean distributions. The effects of both sample size and dependency levels among samples are examined for various value of tau (denoting the size of the spatial kernel for the estimator). The results suggest that even for small degrees of spatial dependency, the tau estimator exhibits significantly stronger normality properties than does the classical estimator of standardized sample means. ?? 1992.

  12. LONG-TERM VARIABILITY OF BRONCHIAL RESPONSIVENESS TO HISTAMINE IN A RANDOM-POPULATION SAMPLE OF ADULTS

    NARCIS (Netherlands)

    RIJCKEN, B; SCHOUTEN, JP; WEISS, ST; ROSNER, B; DEVRIES, K; VANDERLENDE, R

    1993-01-01

    Long-term variability of bronchial responsiveness has been studied in a random population sample of adults. During a follow-up period of 18 yr, 2,216 subjects contributed 5,012 observations to the analyses. Each subject could have as many as seven observations. Bronchial responsiveness was assessed

  13. Albumin to creatinine ratio in a random urine sample: Correlation with severity of preeclampsia

    Directory of Open Access Journals (Sweden)

    Fady S. Moiety

    2014-06-01

    Conclusions: Random urine ACR may be a reliable method for prediction and assessment of severity of preeclampsia. Using the estimated cut-off may add to the predictive value of such a simple quick test.

  14. Risk factors for operated carpal tunnel syndrome: a multicenter population-based case-control study

    Directory of Open Access Journals (Sweden)

    Mandes Anna

    2009-09-01

    Full Text Available Abstract Background Carpal tunnel syndrome (CTS is a socially and economically relevant disease caused by compression or entrapment of the median nerve within the carpal tunnel. This population-based case-control study aims to investigate occupational/non-occupational risk factors for surgically treated CTS. Methods Cases (n = 220 aged 18-65 years were randomly drawn from 13 administrative databases of citizens who were surgically treated with carpal tunnel release during 2001. Controls (n = 356 were randomly sampled from National Health Service registry records and were frequency matched by age-gender-specific CTS hospitalization rates. Results At multivariate analysis, risk factors were blue-collar/housewife status, BMI ≥ 30 kg/m2, sibling history of CTS and coexistence of trigger finger. Being relatively tall (cut-offs based on tertiles: women ≥165 cm; men ≥175 cm was associated with lower risk. Blue-collar work was a moderate/strong risk factor in both sexes. Raised risks were apparent for combinations of biomechanical risk factors that included frequent repetitivity and sustained force. Conclusion This study strongly underlines the relevance of biomechanical exposures in both non-industrial and industrial work as risk factors for surgically treated CTS.

  15. Evaluation of a Class of Simple and Effective Uncertainty Methods for Sparse Samples of Random Variables and Functions

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Vicente [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bonney, Matthew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schroeder, Benjamin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Weirs, V. Gregory [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-11-01

    When very few samples of a random quantity are available from a source distribution of unknown shape, it is usually not possible to accurately infer the exact distribution from which the data samples come. Under-estimation of important quantities such as response variance and failure probabilities can result. For many engineering purposes, including design and risk analysis, we attempt to avoid under-estimation with a strategy to conservatively estimate (bound) these types of quantities -- without being overly conservative -- when only a few samples of a random quantity are available from model predictions or replicate experiments. This report examines a class of related sparse-data uncertainty representation and inference approaches that are relatively simple, inexpensive, and effective. Tradeoffs between the methods' conservatism, reliability, and risk versus number of data samples (cost) are quantified with multi-attribute metrics use d to assess method performance for conservative estimation of two representative quantities: central 95% of response; and 10-4 probability of exceeding a response threshold in a tail of the distribution. Each method's performance is characterized with 10,000 random trials on a large number of diverse and challenging distributions. The best method and number of samples to use in a given circumstance depends on the uncertainty quantity to be estimated, the PDF character, and the desired reliability of bounding the true value. On the basis of this large data base and study, a strategy is proposed for selecting the method and number of samples for attaining reasonable credibility levels in bounding these types of quantities when sparse samples of random variables or functions are available from experiments or simulations.

  16. Sampling

    CERN Document Server

    Thompson, Steven K

    2012-01-01

    Praise for the Second Edition "This book has never had a competitor. It is the only book that takes a broad approach to sampling . . . any good personal statistics library should include a copy of this book." —Technometrics "Well-written . . . an excellent book on an important subject. Highly recommended." —Choice "An ideal reference for scientific researchers and other professionals who use sampling." —Zentralblatt Math Features new developments in the field combined with all aspects of obtaining, interpreting, and using sample data Sampling provides an up-to-date treat

  17. Beyond Random Walk and Metropolis-Hastings Samplers: Why You Should Not Backtrack for Unbiased Graph Sampling

    CERN Document Server

    Lee, Chul-Ho; Eun, Do Young

    2012-01-01

    Graph sampling via crawling has been actively considered as a generic and important tool for collecting uniform node samples so as to consistently estimate and uncover various characteristics of complex networks. The so-called simple random walk with re-weighting (SRW-rw) and Metropolis-Hastings (MH) algorithm have been popular in the literature for such unbiased graph sampling. However, an unavoidable downside of their core random walks -- slow diffusion over the space, can cause poor estimation accuracy. In this paper, we propose non-backtracking random walk with re-weighting (NBRW-rw) and MH algorithm with delayed acceptance (MHDA) which are theoretically guaranteed to achieve, at almost no additional cost, not only unbiased graph sampling but also higher efficiency (smaller asymptotic variance of the resulting unbiased estimators) than the SRW-rw and the MH algorithm, respectively. In particular, a remarkable feature of the MHDA is its applicability for any non-uniform node sampling like the MH algorithm,...

  18. Identifying the origin of groundwater samples in a multi-layer aquifer system with Random Forest classification

    Science.gov (United States)

    Baudron, Paul; Alonso-Sarría, Francisco; García-Aróstegui, José Luís; Cánovas-García, Fulgencio; Martínez-Vicente, David; Moreno-Brotóns, Jesús

    2013-08-01

    Accurate identification of the origin of groundwater samples is not always possible in complex multilayered aquifers. This poses a major difficulty for a reliable interpretation of geochemical results. The problem is especially severe when the information on the tubewells design is hard to obtain. This paper shows a supervised classification method based on the Random Forest (RF) machine learning technique to identify the layer from where groundwater samples were extracted. The classification rules were based on the major ion composition of the samples. We applied this method to the Campo de Cartagena multi-layer aquifer system, in southeastern Spain. A large amount of hydrogeochemical data was available, but only a limited fraction of the sampled tubewells included a reliable determination of the borehole design and, consequently, of the aquifer layer being exploited. Added difficulty was the very similar compositions of water samples extracted from different aquifer layers. Moreover, not all groundwater samples included the same geochemical variables. Despite of the difficulty of such a background, the Random Forest classification reached accuracies over 90%. These results were much better than the Linear Discriminant Analysis (LDA) and Decision Trees (CART) supervised classification methods. From a total of 1549 samples, 805 proceeded from one unique identified aquifer, 409 proceeded from a possible blend of waters from several aquifers and 335 were of unknown origin. Only 468 of the 805 unique-aquifer samples included all the chemical variables needed to calibrate and validate the models. Finally, 107 of the groundwater samples of unknown origin could be classified. Most unclassified samples did not feature a complete dataset. The uncertainty on the identification of training samples was taken in account to enhance the model. Most of the samples that could not be identified had an incomplete dataset.

  19. Soil map disaggregation improved by soil-landscape relationships, area-proportional sampling and random forest implementation

    DEFF Research Database (Denmark)

    Møller, Anders Bjørn; Malone, Brendan P.; Odgers, Nathan

    algorithm were evaluated. The resulting maps were validated on 777 soil profiles situated in a grid covering Denmark. The experiments showed that the results obtained with Jacobsen’s map were more accurate than the results obtained with the CEC map, despite a nominally coarser scale of 1:2,000,000 vs. 1...... of European Communities (CEC, 1985) respectively, both using the FAO 1974 classification. Furthermore, the effects of implementing soil-landscape relationships, using area proportional sampling instead of per polygon sampling, and replacing the default C5.0 classification tree algorithm with a random forest......:1,000,000. This finding is probably related to the fact that Jacobsen’s map was more detailed with a larger number of polygons, soil map units and soil types, despite its coarser scale. The results showed that the implementation of soil-landscape relationships, area-proportional sampling and the random forest...

  20. Risk factors in multiple sclerosis: a population-based case-control study in Sicily. Background and methods.

    Science.gov (United States)

    Nicoletti, Alessandra; Messina, Silvia; Bruno, Elisa; Mostile, Giovanni; Quattrocchi, Graziella; Raciti, Loredana; Dibilio, Valeria; Cappellani, Roberto; D'Amico, Emanuele; Sciacca, Giorgia; Lo Fermo, Salvatore; Paradisi, Vincenza; Patti, Francesco; Zappia, Mario

    2016-12-01

    Incidence of multiple sclerosis (MS) has steeply increased over time during the last 30 years in the city of Catania. We carried out a population-based case-control study to evaluate the possible role of both environmental and genetic factors. From 1975 to 2004 in Catania, 367 MS patients diagnosed according to the Poser's criteria had the onset of disease. A sample of MS patients was randomly selected from this incident cohort. Three controls matched by age and sex were randomly selected from the rosters of 14 GPs. Controls were proportionally selected according to the distribution by municipality of the target population using a multistage sampling methods. All cases and controls underwent a face-to-face interview to record information concerning environmental factors and a blood sample was taken for serological and genetic analysis. 164 MS patients (64 % women; mean age of 46.4 ± 10.7) and 481 controls (69 % women; mean age of 47.7 ± 14.8) were enrolled in the study. The distribution of the whole population and the selected controls by municipalities was similar. A blood sample was taken from 150 MS cases and from 337 controls. At the end of the enrolment, we obtained a representative sample of the MS cases and population controls avoiding possible selection bias. Participation rate was very high also concerning the collection of biological specimens.

  1. Assessment of military population-based psychological resilience programs.

    Science.gov (United States)

    Morgan, Brenda J; Bibb, Sandra C Garmon

    2011-09-01

    Active duty service members' (ADSMs) seemingly poor adaptability to traumatic stressors is a risk to force health. Enhancing the psychological resilience of ADSMs has become a key focus of Department of Defense (DoD) leaders and the numbers of military programs for enhancing psychological resilience have increased. The purpose of this article is to describe the results of an assessment conducted to determine comprehensiveness of current psychological resilience building programs that target ADSMs. A modified six-step, population-based needs assessment was used to evaluate resilience programs designed to meet the psychological needs of the ADSM population. The assessment results revealed a gap in published literature regarding program outcomes. DoD leaders may benefit from targeted predictive research that assesses program effectiveness outcomes. The necessity of including preventive, evidence-based interventions in new programs, such as positive emotion interventions shown to enhance psychological resilience in civilian samples, is also recommended.

  2. Urinary incontinence and hydration: A population-based analysis.

    Science.gov (United States)

    Willis-Gray, Marcella; Wu, Jennifer M; Markland, Alayne

    2017-04-18

    To determine if there is an association between urinary incontinence (UI) and an objective measure of hydration status in men and women in a nationwide, population-based sample. We utilized data from the 2009 to 2010 and 2011 to 2012 National Health and Nutrition Examination Surveys (NHANES), cross sectional surveys of the US non-institutionalized population. Our primary outcome was moderate/severe UI measured using a validated scale. Our exposure of interest was hydration status. Urine osmolality ≥ 800 mOsm/kg defined dehydration versus adequate hydration (kidney disease, the interaction of age with osmolality, and hysterectomy (women only). Among the 11 482 total subjects, 9497 (83%-4882 men and 4615 women) had both UI and urine osmolality data. Compared to women, men were less likely to report UI (5.9% vs 18.9%; P incontinence in men or women. © 2017 Wiley Periodicals, Inc.

  3. Regular exercise, anxiety, depression and personality: A population-based study

    NARCIS (Netherlands)

    de Moor, M.H.M.; Beem, A.L.; Stubbe, J.H.; Boomsma, D.I.; de Geus, E.J.C.

    2006-01-01

    Objectives: To examine whether regular exercise is associated with anxiety, depression and personality in a large population-based sample as a function of gender and age. Methods: The sample consisted of adolescent and adult twins and their families (N = 19,288) who participated in the study on

  4. Regular exercise, anxiety, depression and personality: a population-based study

    NARCIS (Netherlands)

    de Moor, M. H. M.; Beem, A. L.; Stubbe, J. H.; Boomsma, D. I.; de Geus, E. J. C.

    2006-01-01

    To examine whether regular exercise is associated with anxiety, depression and personality in a large population-based sample as a function of gender and age. The sample consisted of adolescent and adult twins and their families (N=19,288) who participated in the study on lifestyle and health from

  5. Direct medical costs of constipation in children over 15 years: a population-based birth cohort

    Science.gov (United States)

    Choung, Rok Seon; Shah, Nilay D.; Chitkara, Denesh; Branda, Megan E.; Van Tilburg, Miranda A.; Whitehead, William E.; Katusic, Slavica K.; Locke, G. Richard; Talley, Nicholas J.

    2011-01-01

    Background Although direct medical costs for constipation-related medical visits are thought to be high, to date there have been no studies examining if longitudinal resource utilization is persistently elevated in children with constipation. Our aim was to estimate the incremental direct medical costs and types of health care utilization associated with constipation from childhood to early adulthood. Methods A nested case-control study was conducted to evaluate the incremental costs associated with constipation. The original sample consisted of 5,718 children in a population-based birth cohort who were born during 1976–1982 in Rochester, MN. The cases included individuals who presented to medical facilities with constipation. The controls were matched and randomly selected among all non-cases in the sample. Direct medical costs for cases and controls were collected from the time subjects were between 5–18 years of age or until the subject emigrated from the community. Results We identified 250 cases with a diagnosis of constipation in the birth cohort. While the mean inpatient costs for cases were $9994 (95% CI=2538, 37201) compared to $2391 (95% CI=923, 7452) for controls (p=0.22) over the time period, the mean outpatient costs for cases were $13927 (95% CI=11325, 16525) compared to $3448 (95% CI=3771, 4621) for controls (pconstipation have higher medical care utilization. Outpatient costs and ER utilization were significantly greater for individuals with constipation from childhood to early adulthood. PMID:20890220

  6. BDNF gene polymorphism, cognition and symptom severity in a Brazilian population-based sample of first-episode psychosis subjects Polimorfismo do gene do BDNF, cognição e gravidade dos sintomas em uma amostra de base populacional brasileira de indivíduos apresentando o primeiro episódio psicótico

    Directory of Open Access Journals (Sweden)

    Eduardo Martinho Jr

    2012-10-01

    Full Text Available OBJECTIVE: To investigate the influence of brain-derived neurotrophic factor (BDNF gene variations on cognitive performance and clinical symptomatology in first-episode psychosis (FEP. METHODS: We performed BDNF val66met variant genotyping, cognitive testing (verbal fluency and digit spans and assessments of symptom severity (as assessed with the PANSS in a population-based sample of FEP patients (77 with schizophreniform psychosis and 53 with affective psychoses and 191 neighboring healthy controls. RESULTS: There was no difference in the proportion of Met allele carriers between FEP patients and controls, and no significant influence of BDNF genotype on cognitive test scores in either of the psychosis groups. A decreased severity of negative symptoms was found in FEP subjects that carried a Met allele, and this finding reached significance for the subgroup with affective psychoses (p OBJETIVO: Investigar a influência da variação do gene do fator neurotrófico derivado do cérebro (BDNF no desempenho cognitivo e na sintomatologia clínica durante o primeiro episódio psicótico (PEP. MÉTODOS: Foram realizados a genotipificação das variantes Val66met do BDNF, o teste cognitivo (fluência verbal e repetição de dígitos e as avaliações da gravidade dos sintomas (conforme avaliado pela Positive and Negative Syndrome Scale [PANSS] em uma amostra de pacientes com PEP de base populacional (77 com psicose esquizofreniforme e 53 com psicose afetiva e 191 vizinhos controle saudáveis. RESULTADOS: Não houve diferença na proporção de portadores do alelo Met entre pacientes com PEP e o grupo controle. Não houve influência significativa do genótipo do BDNF sobre a pontuação de cada um dos grupos psicóticos. Foi encontrada uma diminuição da gravidade dos sintomas negativos em sujeitos com PEP portadores do alelo Met, e essa descoberta mostrou-se significativa para o subgrupo com psicose afetiva (p < 0,01, ANOVA. CONCLUSÕES: Os

  7. Randomization tests

    CERN Document Server

    Edgington, Eugene

    2007-01-01

    Statistical Tests That Do Not Require Random Sampling Randomization Tests Numerical Examples Randomization Tests and Nonrandom Samples The Prevalence of Nonrandom Samples in Experiments The Irrelevance of Random Samples for the Typical Experiment Generalizing from Nonrandom Samples Intelligibility Respect for the Validity of Randomization Tests Versatility Practicality Precursors of Randomization Tests Other Applications of Permutation Tests Questions and Exercises Notes References Randomized Experiments Unique Benefits of Experiments Experimentation without Mani

  8. Fasting time and lipid parameters: association with hepatic steatosis — data from a random population sample

    Science.gov (United States)

    2014-01-01

    Background Current guidelines recommend measuring plasma lipids in fasting patients. Recent studies, however, suggest that variation in plasma lipid concentrations secondary to fasting time may be minimal. Objective of the present study was to investigate the impact of fasting time on plasma lipid concentrations (total cholesterol, HDL and LDL cholesterol, triglycerides). A second objective was to determine the effect of non-alcoholic fatty liver disease exerted on the above-mentioned lipid levels. Method Subjects participating in a population-based cross-sectional study (2,445 subjects; 51.7% females) were questioned at time of phlebotomy regarding duration of pre-phlebotomy fasting. Total cholesterol, LDL and HDL cholesterol, and triglycerides were determined and correlated with length of fasting. An upper abdominal ultrasonographic examination was performed and body-mass index (BMI) and waist-to-hip ratio (WHR) were calculated. Subjects were divided into three groups based on their reported fasting periods of 1–4 h, 4–8 h and > 8 h. After application of the exclusion criteria, a total of 1,195 subjects (52.4% females) were included in the study collective. The Kruskal-Wallis test was used for continuous variables and the chi-square test for categorical variables. The effects of age, BMI, WHR, alcohol consumption, fasting time and hepatic steatosis on the respective lipid variables were analyzed using multivariate logistic regression. Results At multivariate analysis, fasting time was associated with elevated triglycerides (p = 0.0047 for 1–4 h and p = 0.0147 for 4–8 h among females; p fasting period. LDL cholesterol and triglycerides exhibit highly significant variability; the greatest impact is seen with the triglycerides. Fasting time represents an independent factor for reduced LDL cholesterol and elevated triglyceride concentrations. There is a close association between elevated lipids and hepatic steatosis. PMID:24447492

  9. Fasting time and lipid parameters: association with hepatic steatosis--data from a random population sample.

    Science.gov (United States)

    Gruchot, Martin; Graeter, Tilmann; Oeztuerk, Suemeyra; Haenle, Mark Martin; Koenig, Wolfgang; Imhof, Armin; Boehm, Bernhard Otto; Mason, Richard Andrew; Kratzer, Wolfgang; Akinli, Atilla Serif

    2014-01-22

    Current guidelines recommend measuring plasma lipids in fasting patients. Recent studies, however, suggest that variation in plasma lipid concentrations secondary to fasting time may be minimal. Objective of the present study was to investigate the impact of fasting time on plasma lipid concentrations (total cholesterol, HDL and LDL cholesterol, triglycerides). A second objective was to determine the effect of non-alcoholic fatty liver disease exerted on the above-mentioned lipid levels. Subjects participating in a population-based cross-sectional study (2,445 subjects; 51.7% females) were questioned at time of phlebotomy regarding duration of pre-phlebotomy fasting. Total cholesterol, LDL and HDL cholesterol, and triglycerides were determined and correlated with length of fasting. An upper abdominal ultrasonographic examination was performed and body-mass index (BMI) and waist-to-hip ratio (WHR) were calculated. Subjects were divided into three groups based on their reported fasting periods of 1-4 h, 4-8 h and > 8 h. After application of the exclusion criteria, a total of 1,195 subjects (52.4% females) were included in the study collective. The Kruskal-Wallis test was used for continuous variables and the chi-square test for categorical variables. The effects of age, BMI, WHR, alcohol consumption, fasting time and hepatic steatosis on the respective lipid variables were analyzed using multivariate logistic regression. At multivariate analysis, fasting time was associated with elevated triglycerides (p = 0.0047 for 1-4 h and p = 0.0147 for 4-8 h among females; p fasting period. LDL cholesterol and triglycerides exhibit highly significant variability; the greatest impact is seen with the triglycerides. Fasting time represents an independent factor for reduced LDL cholesterol and elevated triglyceride concentrations. There is a close association between elevated lipids and hepatic steatosis.

  10. Finite-sample corrected generalized estimating equation of population average treatment effects in stepped wedge cluster randomized trials.

    Science.gov (United States)

    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.

  11. Securing image information using double random phase encoding and parallel compressive sensing with updated sampling processes

    Science.gov (United States)

    Hu, Guiqiang; Xiao, Di; Wang, Yong; Xiang, Tao; Zhou, Qing

    2017-11-01

    Recently, a new kind of image encryption approach using compressive sensing (CS) and double random phase encoding has received much attention due to the advantages such as compressibility and robustness. However, this approach is found to be vulnerable to chosen plaintext attack (CPA) if the CS measurement matrix is re-used. Therefore, designing an efficient measurement matrix updating mechanism that ensures resistance to CPA is of practical significance. In this paper, we provide a novel solution to update the CS measurement matrix by altering the secret sparse basis with the help of counter mode operation. Particularly, the secret sparse basis is implemented by a reality-preserving fractional cosine transform matrix. Compared with the conventional CS-based cryptosystem that totally generates all the random entries of measurement matrix, our scheme owns efficiency superiority while guaranteeing resistance to CPA. Experimental and analysis results show that the proposed scheme has a good security performance and has robustness against noise and occlusion.

  12. Alcohol and marijuana use in adolescents' daily lives: a random sample of experiences.

    Science.gov (United States)

    Larson, R; Csikszentmihalyi, M; Freeman, M

    1984-07-01

    High school students filled out reports on their experiences at random times during their daily lives, including 48 occasions when they were using alcohol or marijuana. Alcohol use was reported primarily in the context of Friday and Saturday night social gatherings and was associated with a happy and gregarious subjective state. Marijuana use was reported across a wider range of situations and was associated with an average state that differed much less from ordinary experience.

  13. Stemflow estimation in a redwood forest using model-based stratified random sampling

    Science.gov (United States)

    Jack Lewis

    2003-01-01

    Model-based stratified sampling is illustrated by a case study of stemflow volume in a redwood forest. The approach is actually a model-assisted sampling design in which auxiliary information (tree diameter) is utilized in the design of stratum boundaries to optimize the efficiency of a regression or ratio estimator. The auxiliary information is utilized in both the...

  14. Random or systematic sampling to detect a localised microbial contamination within a batch of food

    NARCIS (Netherlands)

    Jongenburger, I.; Reij, M.W.; Boer, E.P.J.; Gorris, L.G.M.; Zwietering, M.H.

    2011-01-01

    Pathogenic microorganisms are known to be distributed heterogeneously in food products that are solid, semi-solid or powdered, like for instance peanut butter, cereals, or powdered milk. This complicates effective detection of the pathogens by sampling. Two-class sampling plans, which are deployed

  15. Multistage point relascope and randomized branch sampling for downed coarse woody debris estimation

    Science.gov (United States)

    Jeffrey H. Gove; Mark J. Ducey; Harry T. Valentine

    2002-01-01

    New sampling methods have recently been introduced that allow estimation of downed coarse woody debris using an angle gauge, or relascope. The theory behind these methods is based on sampling straight pieces of downed coarse woody debris. When pieces deviate from this ideal situation, auxillary methods must be employed. We describe a two-stage procedure where the...

  16. Surgical needs of Nepal: pilot study of population based survey in Pokhara, Nepal.

    Science.gov (United States)

    Gupta, Shailvi; Ranjit, Anju; Shrestha, Ritesh; Wong, Evan G; Robinson, William C; Shrestha, Sunil; Nwomeh, Benedict C; Groen, Reinou S; Kushner, Adam L

    2014-12-01

    The Surgeons OverSeas assessment of surgical need (SOSAS) tool, a population-based survey on surgical conditions in low- and middle-income countries (LMICs), was performed in Sierra Leone and Rwanda. This pilot study in Nepal is the initial implementation of the SOSAS survey in South Asia. A pilot study of SOSAS, modified for Nepal's needs and reprogrammed using mobile data collection software, was undertaken in Pokhara in January 2014. Cluster randomized sampling was utilized to interview 100 individuals in 50 households within two wards of Pokhara, one rural and one urban. The first portion of the survey retrieved demographic data, including household members and time to nearest health facilities. The second portion interviewed two randomly selected individuals from each household, inquiring about surgical conditions covering six anatomical regions. The pilot SOSAS in Nepal was easily completed over 3 days, including training of 18 Nepali interns over 2 days. The response rate was 100 %. A total of 13 respondents had a current surgical need (face 4, chest 1, back 1, abdomen 1, groin 3, extremity 3), although eight reported there was no need for surgical care. Five respondents (5 %) had a current unmet surgical need. The SOSAS pilot study in Nepal was successfully conducted, demonstrating the feasibility of performing SOSAS in South Asia. The estimated 5 % current unmet surgical need will be used for sample size calculation for the full country survey. Utilizing and improving on the SOSAS tool to measure the prevalence of surgical conditions in Nepal will help enumerate the global surgical burden of disease.

  17. Thirty-day postoperative mortality after hysterectomy in women with liver cirrhosis: a Danish population-based cohort study.

    DEFF Research Database (Denmark)

    Lesnikova, Iana

    2002-01-01

    , Building 260, 8000 Aarhus C, Denmark.BACKGROUND: Women with liver cirrhosis have a higher incidence of hysterectomy than the general population, generally because of abnormal bleeding. They may also have an increased risk of postoperative mortality and morbidity. METHODS: In the nationwide Danish National......Thirty-day postoperative mortality after hysterectomy in women with liver cirrhosis: a Danish population-based cohort study.Nielsen IL, Thulstrup AM, Nielsen GL, Larsen H, Vilstrup H, Sorensen HT.Department of Clinical Epidemiology, Aarhus and Aalborg University Hospitals, Vennelyst Boulevard 6...... Patients Register (NPR) we identified all women diagnosed with liver cirrhosis from 1977 to 1993. From this cohort we selected all women undergoing hysterectomy. A random sample of women without liver cirrhosis undergoing hysterectomy was selected as controls. Outcome was defined as mortality within...

  18. Population-Based Prevalence of Cerebral Cavernous Malformations in Older Adults: Mayo Clinic Study of Aging.

    Science.gov (United States)

    Flemming, Kelly D; Graff-Radford, Jonathan; Aakre, Jeremiah; Kantarci, Kejal; Lanzino, Giuseppe; Brown, Robert D; Mielke, Michelle M; Roberts, Rosebud O; Kremers, Walter; Knopman, David S; Petersen, Ronald C; Jack, Clifford R

    2017-07-01

    The prevalence of cerebral cavernous malformation (CCM) is unknown. Case ascertainment in most previous studies was based on autopsy data or clinical convenience samples, often without detailed clinical or radiologic information. To determine the prevalence of CCM in a population-based sample of older adults. This prospective imaging study included 4721 participants aged 50 to 89 years who were enrolled between January 1, 2004, and December 15, 2015, in the Mayo Clinic Study of Aging, a longitudinal, population-based study of residents of Olmsted County, Minnesota. An age- and sex-stratified sampling strategy was used to randomly select participants from Olmsted County using the medical records linkage system of the Rochester Epidemiology Project. Participants were invited to undergo brain magnetic resonance imaging (MRI). Of the 4721 participants, 2715 had an evaluable MRI. All images were reviewed by a board-certified neuroradiologist, and MRI reports were searched for the terms cavernous malformation, cavernous angioma, and cavernoma. Two vascular neurologists reviewed MRIs, and potential CCMs were classified using Zabramski classification. Medical records of the identified individuals with CCM were reviewed along with their demographic information, medical history, and any symptoms referable to the identified CCM lesion. Prevalence of CCM and clinical and radiologic characteristics of study participants with CCM. Of the 2715 participants who underwent MRI scans, 12 (0.44%) had CCM. With the use of inverse probability weights to adjust for participation bias, the overall prevalence was 0.46% (95% CI, 0.05-0.86). The age-adjusted prevalence was found to be 0.61% (95% CI, 0-1.47) for the 50- to 59-year age group, 0.17% (95% CI, 0-0.50) for the 60- to 69-year age group, 0.45% (95% CI, 0.09-0.81) for the 70- to 79-year age group, and 0.58% (95% CI, 0-1.29) for the 80- to 89-year age group. The sex-adjusted prevalence was 0.41% (95% CI, 0-1.00) for women and 0

  19. Random sampling technique for ultra-fast computations of molecular opacities for exoplanet atmospheres

    Science.gov (United States)

    Min, M.

    2017-10-01

    Context. Opacities of molecules in exoplanet atmospheres rely on increasingly detailed line-lists for these molecules. The line lists available today contain for many species up to several billions of lines. Computation of the spectral line profile created by pressure and temperature broadening, the Voigt profile, of all of these lines is becoming a computational challenge. Aims: We aim to create a method to compute the Voigt profile in a way that automatically focusses the computation time into the strongest lines, while still maintaining the continuum contribution of the high number of weaker lines. Methods: Here, we outline a statistical line sampling technique that samples the Voigt profile quickly and with high accuracy. The number of samples is adjusted to the strength of the line and the local spectral line density. This automatically provides high accuracy line shapes for strong lines or lines that are spectrally isolated. The line sampling technique automatically preserves the integrated line opacity for all lines, thereby also providing the continuum opacity created by the large number of weak lines at very low computational cost. Results: The line sampling technique is tested for accuracy when computing line spectra and correlated-k tables. Extremely fast computations ( 3.5 × 105 lines per second per core on a standard current day desktop computer) with high accuracy (≤1% almost everywhere) are obtained. A detailed recipe on how to perform the computations is given.

  20. Hybrid random walk-linear discriminant analysis method for unwrapping quantitative phase microscopy images of biological samples

    Science.gov (United States)

    Kim, Diane N. H.; Teitell, Michael A.; Reed, Jason; Zangle, Thomas A.

    2015-11-01

    Standard algorithms for phase unwrapping often fail for interferometric quantitative phase imaging (QPI) of biological samples due to the variable morphology of these samples and the requirement to image at low light intensities to avoid phototoxicity. We describe a new algorithm combining random walk-based image segmentation with linear discriminant analysis (LDA)-based feature detection, using assumptions about the morphology of biological samples to account for phase ambiguities when standard methods have failed. We present three versions of our method: first, a method for LDA image segmentation based on a manually compiled training dataset; second, a method using a random walker (RW) algorithm informed by the assumed properties of a biological phase image; and third, an algorithm which combines LDA-based edge detection with an efficient RW algorithm. We show that the combination of LDA plus the RW algorithm gives the best overall performance with little speed penalty compared to LDA alone, and that this algorithm can be further optimized using a genetic algorithm to yield superior performance for phase unwrapping of QPI data from biological samples.

  1. Use of protein: creatinine ratio in a random spot urine sample for predicting significant proteinuria in diabetes mellitus.

    Science.gov (United States)

    Yadav, B K; Adhikari, S; Gyawali, P; Shrestha, R; Poudel, B; Khanal, M

    2010-06-01

    Present study was undertaken during a period of 6 months (September 2008-February 2009) to see an correlation of 24 hours urine protein estimation with random spot protein-creatinine (P:C) ratio among a diabetic patients. The study comprised of 144 patients aged 30-70 years, recruited from Kantipur hospital, Kathmandu. The 24-hr urine sample was collected, followed by spot random urine sample. Both samples were analyzed for protein and creatinine excretion. An informed consent was taken from all participants. Sixteen inadequately collected urine samples as defined by (predicted creatinine--measured creatinine)/predicted creatinine > 0.2 were excluded from analysis. The Spearman's rank correlation between the spot urine P:C ratio and 24-hr total protein were performed by the Statistical Package for Social Service. At the P:C ratio cutoff of 0.15 and reference method (24-hr urine protein) cutoff of 150 mg/day, the correlation coefficient was found to be 0.892 (p urine collection but the cutoff should be carefully selected for different patients group under different laboratory procedures and settings.

  2. Risk factors for first trimester miscarriage--results from a UK-population-based case-control study.

    Science.gov (United States)

    Maconochie, N; Doyle, P; Prior, S; Simmons, R

    2007-02-01

    The aim of this study was to examine the association between biological, behavioural and lifestyle risk factors and risk of miscarriage. Population-based case-control study. Case-control study nested within a population-based, two-stage postal survey of reproductive histories of women randomly sampled from the UK electoral register. Six hundred and three women aged 18-55 years whose most recent pregnancy had ended in first trimester miscarriage (traumatic events); high paternal age and changing partner. Previous live birth, nausea, vitamin supplementation and eating fresh fruits and vegetables daily were associated with reduced risk, as were feeling well enough to fly or to have sex. After adjustment for nausea, we did not confirm an association with caffeine consumption, smoking or moderate or occasional alcohol consumption; nor did we find an association with educational level, socio-economic circumstances or working during pregnancy. The results confirm that advice to encourage a healthy diet, reduce stress and promote emotional wellbeing might help women in early pregnancy (or planning a pregnancy) reduce their risk of miscarriage. Findings of increased risk associated with previous termination, stress, change of partner and low pre-pregnancy weight are noteworthy, and we recommend further work to confirm these findings in other study populations.

  3. Sexual Behaviors and HIV Status: A Population-Based Study Among Older Adults in Rural South Africa

    National Research Council Canada - National Science Library

    Rosenberg, Molly S; Gómez-Olivé, Francesc X; Rohr, Julia K; Houle, Brian C; Kabudula, Chodziwadziwa W; Wagner, Ryan G; Salomon, Joshua A; Kahn, Kathleen; Berkman, Lisa F; Tollman, Stephen M; Bärnighausen, Till

    2017-01-01

    .... METHODS:We analyzed data from a population-based sample of 5059 men and women aged 40 years and older from the study Health and Aging in AfricaLongitudinal Studies of INDEPTH Communities (HAALSI...

  4. Prevalence of Chronic Pain, Treatments, Perception, and Interference on Life Activities: Brazilian Population-Based Survey

    Science.gov (United States)

    Perissinotti, Dirce Maria Navas; de Oliveira Junior, Jose Oswaldo; da Fonseca, Paulo Renato Barreiros; Posso, Irimar de Paula

    2017-01-01

    Background and Objectives Chronic pain affects between 30% and 50% of the world population. Our objective was to estimate the prevalence of chronic pain in Brazil, describe and compare differences between pain types and characteristics, and identify the types of therapies adopted and the impact of pain on daily life. Methods Cross-sectional study of a population-based survey with randomized sample from a private database. The interviews were conducted by phone. 78% of the respondents aged 18 years or more agreed to be interviewed, for a total of 723 respondents distributed throughout the country. Independent variables were demographic data, pain and treatment characteristics, and impact of pain on daily life. Comparative and associative statistical analyses were conducted to select variables for nonhierarchical logistic regression. Results Chronic pain prevalence was 39% and mean age was 41 years with predominance of females (56%). We found higher prevalence of chronic pain in the Southern and Southeastern regions. Pain treatment was not specific to gender. Dissatisfaction with chronic pain management was reported by 49% of participants. Conclusion 39% of interviewed participants reported chronic pain, with prevalence of females. Gender-associated differences were found in intensity perception and interference of pain on daily life activities. PMID:29081680

  5. Abnormal Cardiac Structure and Function in the Metabolic Syndrome: A Population-Based Study

    Science.gov (United States)

    Aijaz, Bilal; Ammar, Khawaja A.; Lopez-Jimenez, Francisco; Redfield, Margaret M.; Jacobsen, Steven J.; Rodeheffer, Richard J.

    2009-01-01

    OBJECTIVE To measure the association between cardiac structure and function abnormalities and isolated metabolic syndrome (metabolic syndrome excluding established hypertension or diabetes mellitus). PARTICIPANTS AND METHODS We collected data prospectively on a population-based random sample of 2042 Olmsted County, Minnesota, residents aged 45 years or older who underwent echocardiography between January 1, 1997, and September 30, 2000. Metabolic syndrome was defined by National Cholesterol Education Program Adult Treatment Panel III criteria. RESULTS The prevalence of isolated metabolic syndrome was 21.7% (214/984) in men and 16.7% (177/1058) in women. Left ventricular (LV) mass index was greater (91.7 vs 87.9 g/m2; P=.04) and LV diastolic dysfunction more prevalent (28.2% [50/177] vs 14.9% [81/544]; Psyndrome than in women without metabolic syndrome; no difference was found in men. When patients with hypertension or diabetes mellitus were included in the cohort, there was a stepwise increase in LV mass index and LV diastolic dysfunction from no metabolic syndrome to isolated metabolic syndrome to metabolic syndrome in women and men. CONCLUSION Isolated metabolic syndrome, which is associated with increased LV mass index and LV diastolic dysfunction in women, identifies women with evidence of early ventricular dysfunction. PMID:19046554

  6. Increased Risk of Hemorrhagic Stroke in Patients with Migraine: A Population-Based Cohort Study

    Science.gov (United States)

    Kuo, Cheng-Ya; Yen, Ming-Fang; Chen, Li-Sheng; Fann, Ching-Yuan; Chiu, Yueh-Hsia; Chen, Hsiu-Hsi; Pan, Shin-Liang

    2013-01-01

    Objective Previous studies on the association between migraine and the risk of developing hemorrhagic stroke (HS) have generated inconsistent results. The aim of the present population-based, age- and sex- matched follow-up study was to investigate whether migraine is associated with an increased risk of HS. Method A total of 20925 persons with at least two ambulatory visits in 2001 with the principal diagnosis of migraine were enrolled in the migraine group. The non-migraine group consisted of 104625, age- and sex- matched, randomly sampled subjects without migraine. The two-year HS-free survival rates for these 2 groups were estimated using the Kaplan-Meier method. Cox proportional hazards regression was used to estimate the effect of migraine on the occurrence of HS. Results During the 2 year follow-up, 113 subjects in the migraine group (0.54%) and 255 in the non-migraine group (0.24%) developed HS. The crude hazard ratio (HR) for developing HS in the migraine group was 2.22 compared to the non-migraine group (95% confidence interval [CI]: 1.78–2.77, pmigraine was linked to an increased risk of HS. PMID:23372843

  7. Air Pollution and the Risk of Cardiac Defects: A Population-Based Case-Control Study.

    Science.gov (United States)

    Hwang, Bing-Fang; Lee, Yungling Leo; Jaakkola, Jouni J K

    2015-11-01

    Previous epidemiologic studies have assessed the role of the exposure to ambient air pollution in the development of cardiac birth defects, but they have provided somewhat inconsistent results. To assess the associations between exposure to ambient air pollutants and the risk of cardiac defects, a population-based case-control study was conducted using 1087 cases of cardiac defects and a random sample of 10,870 controls from 1,533,748 Taiwanese newborns in 2001 to 2007.Logistic regression was performed to calculate odds ratios for 10 ppb increases in O3 and 10 μg/m increases in PM10. In addition, we compared the risk of cardiac defects in 4 categories-high exposure (>75th percentile); medium exposure (75th to 50th percentile); low exposure (percentile); reference (percentile) based on the distribution of each pollutant. The risks of ventricular septal defects (VSD), atrial septal defects (ASD), and patent ductus arteriosus (PDA) were associated with 10 ppb increases in O3 exposure during the first 3 gestational months among term and preterm babies. In comparison between high PM10 exposure and reference category, there were statistically significant elevations in the effect estimates of ASD for all and terms births. In addition, there was a negative or weak association between SO2, NO2, CO, and cardiac defects.The study proved that exposure to outdoor air O3 and PM10 during the first trimester of gestation may increase the risk of VSD, ASD, and PDA.

  8. THE RHETORICAL USE OF RANDOM SAMPLING: CRAFTING AND COMMUNICATING THE PUBLIC IMAGE OF POLLS AS A SCIENCE (1935-1948).

    Science.gov (United States)

    Lusinchi, Dominic

    2017-03-01

    The scientific pollsters (Archibald Crossley, George H. Gallup, and Elmo Roper) emerged onto the American news media scene in 1935. Much of what they did in the following years (1935-1948) was to promote both the political and scientific legitimacy of their enterprise. They sought to be recognized as the sole legitimate producers of public opinion. In this essay I examine the, mostly overlooked, rhetorical work deployed by the pollsters to publicize the scientific credentials of their polling activities, and the central role the concept of sampling has had in that pursuit. First, they distanced themselves from the failed straw poll by claiming that their sampling methodology based on quotas was informed by science. Second, although in practice they did not use random sampling, they relied on it rhetorically to derive the symbolic benefits of being associated with the "laws of probability." © 2017 Wiley Periodicals, Inc.

  9. Multivariate Multi-Objective Allocation in Stratified Random Sampling: A Game Theoretic Approach.

    Science.gov (United States)

    Muhammad, Yousaf Shad; Hussain, Ijaz; Shoukry, Alaa Mohamd

    2016-01-01

    We consider the problem of multivariate multi-objective allocation where no or limited information is available within the stratum variance. Results show that a game theoretic approach (based on weighted goal programming) can be applied to sample size allocation problems. We use simulation technique to determine payoff matrix and to solve a minimax game.

  10. The effect of dead time on randomly sampled power spectral estimates

    DEFF Research Database (Denmark)

    Buchhave, Preben; Velte, Clara Marika; George, William K.

    2014-01-01

    consider both the effect on the measured spectrum of a finite sampling time, i.e., a finite time during which the signal is acquired, and a finite dead time, that is a time in which the signal processor is busy evaluating a data point and therefore unable to measure a subsequent data point arriving within...... the dead time delay....

  11. Phase microscopy of technical and biological samples through random phase modulation with a difuser

    DEFF Research Database (Denmark)

    Almoro, Percival; Pedrini, Giancarlo; Gundu, Phanindra Narayan

    2010-01-01

    A technique for phase microscopy using a phase diffuser and a reconstruction algorithm is proposed. A magnified specimen wavefront is projected on the diffuser plane that modulates the wavefront into a speckle field. The speckle patterns at axially displaced planes are sampled and used in an iter...

  12. Random Evolutionary Dynamics Driven by Fitness and House-of-Cards Mutations: Sampling Formulae

    Science.gov (United States)

    Huillet, Thierry E.

    2017-07-01

    We first revisit the multi-allelic mutation-fitness balance problem, especially when mutations obey a house of cards condition, where the discrete-time deterministic evolutionary dynamics of the allelic frequencies derives from a Shahshahani potential. We then consider multi-allelic Wright-Fisher stochastic models whose deviation to neutrality is from the Shahshahani mutation/selection potential. We next focus on the weak selection, weak mutation cases and, making use of a Gamma calculus, we compute the normalizing partition functions of the invariant probability densities appearing in their Wright-Fisher diffusive approximations. Using these results, generalized Ewens sampling formulae (ESF) from the equilibrium distributions are derived. We start treating the ESF in the mixed mutation/selection potential case and then we restrict ourselves to the ESF in the simpler house-of-cards mutations only situation. We also address some issues concerning sampling problems from infinitely-many alleles weak limits.

  13. A Population-Based Study of Preschoolers' Food Neophobia and Its Associations with Food Preferences

    Science.gov (United States)

    Russell, Catherine Georgina; Worsley, Anthony

    2008-01-01

    Objective: This cross-sectional study was designed to investigate the relationships between food preferences, food neophobia, and children's characteristics among a population-based sample of preschoolers. Design: A parent-report questionnaire. Setting: Child-care centers, kindergartens, playgroups, day nurseries, and swimming centers. Subjects:…

  14. Health-Related Quality of Life in Cervical Cancer Survivors: A Population-Based Survey

    NARCIS (Netherlands)

    I.J. Korfage (Ida); M.L.E. Essink-Bot (Marie-Louise); F. Mols (Floortje); L.V. van de Poll-Franse (Lonneke); R.F.M.P. Kruitwagen (Roy); M. van Ballegooijen (Marjolein)

    2009-01-01

    textabstractPURPOSE: In a population-based sample of cervical cancer survivors, health-related quality of life (HRQoL) was assessed 2-10 years postdiagnosis. METHODS AND MATERIALS: All patients given a diagnosis of cervical cancer in 1995-2003 in the Eindhoven region, The Netherlands, and alive

  15. Methods of Suicide among Cancer Patients: A Nationwide Population-Based Study

    Science.gov (United States)

    Chung, Kuo-Hsuan; Lin, Herng-Ching

    2010-01-01

    A 3-year nationwide population-based data set was used to explore methods of suicide (violent vs. nonviolent) and possible contributing factors among cancer patients in Taiwan. A total of 1,065 cancer inpatients who committed suicide were included as our study sample. The regression shows that those who had genitourinary cancer were 0.55 times (p…

  16. A UK population-based study of the relationship between mental disorder and victimisation

    NARCIS (Netherlands)

    Hart, C.; Vet, R. de; Moran, P.; Hatch, S.L.; Dean, K.

    2012-01-01

    PURPOSE: To establish the prevalence of victimisation in a UK population-based sample and to investigate the association between mental disorder and victimisation in both cross-sectional and prospective manner, whilst adjusting for potential confounds. METHODS: Data from the National Child

  17. Normal values and determinants of circadian urine production in older men : A population based study

    NARCIS (Netherlands)

    Blanker, M. H.; Bernsen, R. M.; Bosch, J. L. Ruud; Thomas, S.; Groeneveld, F. P.; Prins, A.; Bohnen, A. M.

    2002-01-01

    PURPOSE: We evaluated circadian urine production and its determinants in a large population based sample of older men. MATERIALS AND METHODS: We collected data on 1,688 men 50 to 78 years old, without radical prostatectomy, prostate or bladder cancer, neurogenic bladder disease or negative advice

  18. Minor Self-Harm and Psychiatric Disorder: A Population-Based Study

    Science.gov (United States)

    Skegg, Keren; Nada-Raja, Shyamala; Moffit, Terrie E.

    2004-01-01

    Little is known about the extent to which minor self-harm in the general population is associated with psychiatric disorder. A population-based sample of 980 young adults was interviewed independently about past-year suicidal and self-harm behavior and thoughts, and psychiatric disorders. Self-harm included self-harmful behaviors such as…

  19. Dual to Ratio-Cum-Product Estimator in Simple and Stratified Random Sampling

    OpenAIRE

    Yunusa Olufadi

    2013-01-01

    New estimators for estimating the finite population mean using two auxiliary variables under simple and stratified sampling design is proposed. Their properties (e.g., mean square error) are studied to the first order of approximation. More so, some estimators are shown to be a particular member of this estimator. Furthermore, comparison of the proposed estimator with the usual unbiased estimator and other estimators considered in this paper reveals interesting results. These results are fur...

  20. The psychometric properties of the AUDIT: a survey from a random sample of elderly Swedish adults.

    Science.gov (United States)

    Källmén, Håkan; Wennberg, Peter; Ramstedt, Mats; Hallgren, Mats

    2014-07-01

    Increasing alcohol consumption and related harms have been reported among the elderly population of Europe. Consequently, it is important to monitor patterns of alcohol use, and to use a valid and reliable tool when screening for risky consumption in this age group. The aim was to evaluate the internal consistency reliability and construct validity of the Alcohol Use Disorders Identification Test (AUDIT) in elderly Swedish adults, and to compare the results with the general Swedish population. Another aim was to calculate the level of alcohol consumption (AUDIT-C) to be used for comparison in future studies. The questionnaire was sent to 1459 Swedish adults aged 79-80 years with a response rate of 73.3%. Internal consistency reliability, were assessed using Cronbach alpha, and confirmatory factor analysis assessed construct validity of the Alcohol Use Disorders Identification Test (AUDIT) in elderly population as compared to a Swedish general population sample. The results showed that AUDIT was more reliable and valid among the Swedish general population sample than among the elderly and that Item 1 and 4 in AUDIT was less reliable and valid among the elderly. While the AUDIT showed acceptable psychometric properties in the general population sample, it's performance was of less quality among the elderly respondents. Further psychometric assessments of the AUDIT in elderly populations are required before it is implemented more widely.

  1. The quality of the reported sample size calculations in randomized controlled trials indexed in PubMed.

    Science.gov (United States)

    Lee, Paul H; Tse, Andy C Y

    2017-05-01

    There are limited data on the quality of reporting of information essential for replication of the calculation as well as the accuracy of the sample size calculation. We examine the current quality of reporting of the sample size calculation in randomized controlled trials (RCTs) published in PubMed and to examine the variation in reporting across study design, study characteristics, and journal impact factor. We also reviewed the targeted sample size reported in trial registries. We reviewed and analyzed all RCTs published in December 2014 with journals indexed in PubMed. The 2014 Impact Factors for the journals were used as proxies for their quality. Of the 451 analyzed papers, 58.1% reported an a priori sample size calculation. Nearly all papers provided the level of significance (97.7%) and desired power (96.6%), and most of the papers reported the minimum clinically important effect size (73.3%). The median (inter-quartile range) of the percentage difference of the reported and calculated sample size calculation was 0.0% (IQR -4.6%;3.0%). The accuracy of the reported sample size was better for studies published in journals that endorsed the CONSORT statement and journals with an impact factor. A total of 98 papers had provided targeted sample size on trial registries and about two-third of these papers (n=62) reported sample size calculation, but only 25 (40.3%) had no discrepancy with the reported number in the trial registries. The reporting of the sample size calculation in RCTs published in PubMed-indexed journals and trial registries were poor. The CONSORT statement should be more widely endorsed. Copyright © 2016 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  2. The burden of headache disorders in Nepal: estimates from a population-based survey.

    Science.gov (United States)

    Manandhar, Kedar; Risal, Ajay; Linde, Mattias; Steiner, Timothy J

    2015-01-01

    Headache disorders, particularly migraine and tension-type headache (TTH), are among the most prevalent global public-health problems. Medication-overuse headache (MOH) is a common sequela of mismanagement of these. Migraine and MOH are highly disabling. Formulation of responsive health policy requires reliable, locally-derived, population-based data describing both individual and societal impact of headache disorders. South-East Asia is the only one of WHO's six world regions in which no such national data have yet been gathered. In a nationwide population-based cross-sectional study, a representative sample of Nepalese-speaking adults (18-65 years) were randomly selected by stratified multistage cluster sampling. Trained interviewers made unannounced door-to-door visits and enquired into headache and its attributable burden using a culturally-adapted and validated Nepalese translation of the Headache-Attributed Restriction, Disability, Social Handicap and Impaired Participation (HARDSHIP) questionnaire. Among 2100 participants, 1794 (85.4 %) reported headache during the preceding year (male: 689 [38.4 %], female 1105 [61.6 %]; mean age 36.1 ± 12.6 years). Mean headache frequency was 3.8 ± 6.2 days/month, mean headache intensity 2.1 ± 0.7 on a 0-3 scale, and mean attack duration 41.9 ± 108.5 h. All aspects of symptom burden (frequency, intensity and duration) were greater among females (p population level, these disorders were responsible for reduced functional capacities of 0.81, 0.06 and 0.20 %. Total lost productive time due to headache was 6.8 % for the 85 % of the population with headache. Males lost more paid worktime than females (p Nepal, are also highly burdensome at both individual and population levels. There is a substantial penalty in lost production. The remedy lies in better health care for headache; structured headache-care services are urgently needed in the country, and likely to be cost-saving.

  3. Annoyance and health symptoms and their influencing factors: a population-based air pollution intervention study.

    Science.gov (United States)

    Stenlund, T; Lidén, E; Andersson, K; Garvill, J; Nordin, S

    2009-04-01

    Interventions for reducing air pollution are important means for improving public health. The role of psychological factors in understanding annoyance and health symptoms due to air pollution is limited and further investigation is required. This study aimed to investigate the effects of an intervention to reduce air pollution (predominantly dust and soot) with respect to perceived pollution, risk perception, annoyance and health symptoms. Another objective was to test a model that describes inter-relations between air pollution, perceived pollution, health risk perception, annoyance and health symptoms. An interventional, population-based questionnaire study. Surveys were performed before (pre-test) and after (post-test) closure of a sinter plant. Instead, pellets were shipped to the community's harbour for steel production. Individuals in the community aged 18-75 years were selected at random for participation in the pre-test (n=738; 74% of the sample participated) and post-test (n=684; 68% of the sample participated). The two samples were representative of the populations at the two points in time, and thus not identical. After the sinter plant was closed, the environment was perceived as being less dusty, the residents were more positive in their risk perception, and they reported less annoyance due to dust, soot and odorous substances. No difference was found for health symptoms between the pre-test and the post-test. Based on path analyses, a model is proposed of inter-relations between air pollution, perceived pollution, health risk perception, annoyance and health symptoms. The intervention was successful with respect to perceived dust and soot pollution; to annoyance attributed to dust, soot and odorous substances; and to risk perception. The path analyses suggest that perceived pollution and health risk perception play important roles in understanding and predicting environmentally induced annoyance and health symptoms.

  4. Inflammatory cytokines as risk factors for a first venous thrombosis: a prospective population-based study.

    Directory of Open Access Journals (Sweden)

    Sverre C Christiansen

    2006-08-01

    Full Text Available BACKGROUND: In case-control studies, elevated levels of interleukins 6 and 8 have been found to be associated with an increased risk of venous thrombosis (VT. Because of the design of these studies, it remained uncertain whether these alterations were a cause or a result of the VT. In order to distinguish between the two, we set out to measure the levels of six inflammatory markers prior to thrombosis in a population-based cohort using a nested case-cohort design. METHODS AND FINDINGS: Between August 1995 and June 1997, blood was collected from 66,140 people in the second Norwegian Health Study of Nord-Trøndelag (HUNT2. We identified venous thrombotic events occurring between entry and 1 January 2002. By this date we had registered 506 cases with a first VT; an age- and sex-stratified random sample of 1,464 controls without previous VT was drawn from the original cohort. Levels of interleukins 1beta, 6, 8, 10, 12p70, and tumour necrosis factor-alpha were measured in the baseline sample that was taken 2 d to 75 mo before the event (median 33 mo. Cut-off points for levels were the 80th, 90th, and 95th percentile in the control group. With odds ratios ranging from 0.9 (95% CI: 0.6-1.5 to 1.1 (95% CI: 0.7-1.8, we did not find evidence for a relationship between VT and an altered inflammatory profile. CONCLUSIONS: The results from this population sample show that an altered inflammatory profile is more likely to be a result rather than a cause of VT, although short-term effects of transiently elevated levels cannot be ruled out.

  5. Active Learning Not Associated with Student Learning in a Random Sample of College Biology Courses

    Science.gov (United States)

    Andrews, T. M.; Leonard, M. J.; Colgrove, C. A.; Kalinowski, S. T.

    2011-01-01

    Previous research has suggested that adding active learning to traditional college science lectures substantially improves student learning. However, this research predominantly studied courses taught by science education researchers, who are likely to have exceptional teaching expertise. The present study investigated introductory biology courses randomly selected from a list of prominent colleges and universities to include instructors representing a broader population. We examined the relationship between active learning and student learning in the subject area of natural selection. We found no association between student learning gains and the use of active-learning instruction. Although active learning has the potential to substantially improve student learning, this research suggests that active learning, as used by typical college biology instructors, is not associated with greater learning gains. We contend that most instructors lack the rich and nuanced understanding of teaching and learning that science education researchers have developed. Therefore, active learning as designed and implemented by typical college biology instructors may superficially resemble active learning used by education researchers, but lacks the constructivist elements necessary for improving learning. PMID:22135373

  6. Undertreated Hypertension and its Implications for Public Health in Nepal: Nationwide Population-Based Survey.

    Science.gov (United States)

    Koju, R; Manandhar, K; Risal, A; Steiner, T J; Holen, A; Linde, M

    2015-01-01

    Hypertension (HTN), a major risk factor for cardiovascular diseases (CVDs), is a substantial global public health problem. Occasional studies indicate a high prevalence of HTN in the Nepalese population, but no nationwide population-based data exist so far. We opportunistically used a survey of major disorders of the brain in Nepal to measure blood pressure (BP) in participants selected randomly from the adult general population. To establish the prevalence of elevated BP (eBP), and factors associated with it, regardless of any antihypertensive therapy being taken. We took this to be indicative of unmet health-care need. This was a cross-sectional study, conducted by unannounced household visits, employing multistage random cluster sampling. To achieve representativeness, 15 districts out of 75 in the country were investigated: one district from each of the three physiographic divisions in each of the five development regions of Nepal. One adult aged 18-65 years was selected from each household and interviewed by structured questionnaire. BP was recorded in a standardised manner by digital device (Microlife 3BM1-3®). From 2,109 eligible households, 2,100 adults (99.6%) participated. The prevalence of eBP (>140/90 mmHg on ≥2 readings) was found to be 15.1%. Multivariate logistic regression showed significant and independent associations with demographic variables (higher age, male gender), with life-style factors (daily alcohol consumption, BMI ≥25), and with living at high altitude (≥2000 m). In the context of the survey we could not collect data on antihypertensive therapy being taken but, clearly, whatever this might have been, it was failing to meet treatment needs. Almost one in six adults met criteria for hypertension, carrying risk implications for CVDs and their substantial public-health consequences. Two remediable associated factors were identified, although in a cross-sectional survey we could not prove causation.

  7. The Prevalence and Causes of Primary Infertility in Iran: A Population-Based Study.

    Science.gov (United States)

    Kazemijaliseh, Hadigheh; Ramezani Tehrani, Fahimeh; Behboudi-Gandevani, Samira; Hosseinpanah, Farhad; Khalili, Davood; Azizi, Fereidoun

    2015-04-19

    Primary infertility is a health issue among women over the world. The aim of this study was to investigate the prevalence and causes of primary infertility based on a population-based study in an urban area of Iran. In a cross-sectional study, a total of 1067 married women who participated in the Tehran Lipid and Glucose Study were randomly selected using systematic random sampling. Unmarried women, those with unwilling pregnancy and duration of marriage below one year were excluded from the study. Data was collected by using validated ad-hoc questionnaires. Descriptive and inferential statistics were used for data analysis. The mean (SD) of age and marriage age of the studied women were 40.3 (9.3) and 20.6 (4.49) years, respectively; the overall prevalence of lifetime primary infertility among couples was 17.3% (185/1067). Ovulatory disorder (39.7%) and male factors (29.1%) were the main causes of primary infertility. In addition, 31 (17%) of the women were diagnosed with more than one cause. According to the logistic regression analysis, primary infertility was independently related to the old age of women (OR: 1.37; 95% CI: 1.14-13.63, P.value: 0.001), higher BMI (OR: 1.95; 95% CI: 1.87-4.14, P.value: 0.003), active smoking (OR: 1.47; 95% CI: 1.38-3.53, P.value: 0.012) and higher educational level (OR: 2.23; 95% CI: 1.12-5.53, P.value: 0.03). The prevalence of primary infertility in Iran was higher than the worldwide trends of infertility, indicating that understanding such risks help healthcare providers and policy makers to design and implement interventions to slow down this trend.

  8. Comparison of population-based association study methods correcting for population stratification.

    Directory of Open Access Journals (Sweden)

    Feng Zhang

    Full Text Available Population stratification can cause spurious associations in population-based association studies. Several statistical methods have been proposed to reduce the impact of population stratification on population-based association studies. We simulated a set of stratified populations based on the real haplotype data from the HapMap ENCODE project, and compared the relative power, type I error rates, accuracy and positive prediction value of four prevailing population-based association study methods: traditional case-control tests, structured association (SA, genomic control (GC and principal components analysis (PCA under various population stratification levels. Additionally, we evaluated the effects of sample sizes and frequencies of disease susceptible allele on the performance of the four analytical methods in the presence of population stratification. We found that the performance of PCA was very stable under various scenarios. Our comparison results suggest that SA and PCA have comparable performance, if sufficient ancestral informative markers are used in SA analysis. GC appeared to be strongly conservative in significantly stratified populations. It may be better to apply GC in the stratified populations with low stratification level. Our study intends to provide a practical guideline for researchers to select proper study methods and make appropriate inference of the results in population-based association studies.

  9. Effect of the Mediterranean diet on heart failure biomarkers: a randomized sample from the PREDIMED trial.

    Science.gov (United States)

    Fitó, Montserrat; Estruch, Ramón; Salas-Salvadó, Jordi; Martínez-Gonzalez, Miguel Angel; Arós, Fernando; Vila, Joan; Corella, Dolores; Díaz, Oscar; Sáez, Guillermo; de la Torre, Rafael; Mitjavila, María-Teresa; Muñoz, Miguel Angel; Lamuela-Raventós, Rosa-María; Ruiz-Gutierrez, Valentina; Fiol, Miquel; Gómez-Gracia, Enrique; Lapetra, José; Ros, Emilio; Serra-Majem, Lluis; Covas, María-Isabel

    2014-05-01

    Scarce data are available on the effect of the traditional Mediterranean diet (TMD) on heart failure biomarkers. We assessed the effect of TMD on biomarkers related to heart failure in a high cardiovascular disease risk population. A total of 930 subjects at high cardiovascular risk (420 men and 510 women) were recruited in the framework of a multicentre, randomized, controlled, parallel-group clinical trial directed at testing the efficacy of the TMD on the primary prevention of cardiovascular disease (The PREDIMED Study). Participants were assigned to a low-fat diet (control, n = 310) or one of two TMDs [TMD + virgin olive oil (VOO) or TMD + nuts]. Depending on group assignment, participants received free provision of extra-virgin olive oil, mixed nuts, or small non-food gifts. After 1 year of intervention, both TMDs decreased plasma N-terminal pro-brain natriuretic peptide, with changes reaching significance vs. control group (P cardiovascular disease (CVD) who improved their diet toward a TMD pattern reduced their N-terminal pro-brain natriuretic peptide compared with those assigned to a low-fat diet. The same was found for in vivo oxidized low-density lipoprotein and lipoprotein(a) plasma concentrations after the TMD + VOO diet. From our results TMD could be a useful tool to mitigate against risk factors for heart failure. From our results TMD could modify markers of heart failure towards a more protective mode. © 2014 The Authors. European Journal of Heart Failure © 2014 European Society of Cardiology.

  10. Sequential sampling model for multiattribute choice alternatives with random attention time and processing order.

    Science.gov (United States)

    Diederich, Adele; Oswald, Peter

    2014-01-01

    A sequential sampling model for multiattribute binary choice options, called multiattribute attention switching (MAAS) model, assumes a separate sampling process for each attribute. During the deliberation process attention switches from one attribute consideration to the next. The order in which attributes are considered as well for how long each attribute is considered-the attention time-influences the predicted choice probabilities and choice response times. Several probability distributions for the attention time with different variances are investigated. Depending on the time and order schedule the model predicts a rich choice probability/choice response time pattern including preference reversals and fast errors. Furthermore, the difference between finite and infinite decision horizons for the attribute considered last is investigated. For the former case the model predicts a probability p 0 > 0 of not deciding within the available time. The underlying stochastic process for each attribute is an Ornstein-Uhlenbeck process approximated by a discrete birth-death process. All predictions are also true for the widely applied Wiener process.

  11. Sequential sampling model for multiattribute choice alternatives with random attention time and processing order

    Directory of Open Access Journals (Sweden)

    Adele eDiederich

    2014-09-01

    Full Text Available A sequential sampling model for multiattribute binary choice options, called Multiattribute attention switching (MAAS model, assumes a separate sampling process for each attribute. During the deliberation process attention switches from one attribute consideration to the next. The order in which attributes are considered as well for how long each attribute is considered - the attention time - influences the predicted choice probabilities and choice response times. Several probability distributions for the attention time including deterministic, Poisson, binomial, geometric, and uniform with different variances are investigated. Depending on the time and order schedule the model predicts a rich choice probability/choice response time pattern including preference reversals and fast errors. Furthermore, the difference between a finite and infinite decision horizons for the attribute considered last is investigated. For the former case the model predicts a probability $p_0> 0$ of not deciding within the available time. The underlying stochastic process for each attribute is an Ornstein-Uhlenbeck process approximated by a discrete birth-death process. All predictions are also true for the widely applied Wiener process.

  12. Incorporating covariance estimation uncertainty in spatial sampling design for prediction with trans-Gaussian random fields

    Directory of Open Access Journals (Sweden)

    Gunter eSpöck

    2015-05-01

    Full Text Available Recently, Spock and Pilz [38], demonstratedthat the spatial sampling design problem forthe Bayesian linear kriging predictor can betransformed to an equivalent experimentaldesign problem for a linear regression modelwith stochastic regression coefficients anduncorrelated errors. The stochastic regressioncoefficients derive from the polar spectralapproximation of the residual process. Thus,standard optimal convex experimental designtheory can be used to calculate optimal spatialsampling designs. The design functionals ̈considered in Spock and Pilz [38] did nottake into account the fact that kriging isactually a plug-in predictor which uses theestimated covariance function. The resultingoptimal designs were close to space-fillingconfigurations, because the design criteriondid not consider the uncertainty of thecovariance function.In this paper we also assume that thecovariance function is estimated, e.g., byrestricted maximum likelihood (REML. Wethen develop a design criterion that fully takesaccount of the covariance uncertainty. Theresulting designs are less regular and space-filling compared to those ignoring covarianceuncertainty. The new designs, however, alsorequire some closely spaced samples in orderto improve the estimate of the covariancefunction. We also relax the assumption ofGaussian observations and assume that thedata is transformed to Gaussianity by meansof the Box-Cox transformation. The resultingprediction method is known as trans-Gaussiankriging. We apply the Smith and Zhu [37]approach to this kriging method and show thatresulting optimal designs also depend on theavailable data. We illustrate our results witha data set of monthly rainfall measurementsfrom Upper Austria.

  13. Generalized SAMPLE SIZE Determination Formulas for Investigating Contextual Effects by a Three-Level Random Intercept Model.

    Science.gov (United States)

    Usami, Satoshi

    2017-03-01

    Behavioral and psychological researchers have shown strong interests in investigating contextual effects (i.e., the influences of combinations of individual- and group-level predictors on individual-level outcomes). The present research provides generalized formulas for determining the sample size needed in investigating contextual effects according to the desired level of statistical power as well as width of confidence interval. These formulas are derived within a three-level random intercept model that includes one predictor/contextual variable at each level to simultaneously cover various kinds of contextual effects that researchers can show interest. The relative influences of indices included in the formulas on the standard errors of contextual effects estimates are investigated with the aim of further simplifying sample size determination procedures. In addition, simulation studies are performed to investigate finite sample behavior of calculated statistical power, showing that estimated sample sizes based on derived formulas can be both positively and negatively biased due to complex effects of unreliability of contextual variables, multicollinearity, and violation of assumption regarding the known variances. Thus, it is advisable to compare estimated sample sizes under various specifications of indices and to evaluate its potential bias, as illustrated in the example.

  14. Comparison of Detrusor Muscle Sampling Rate in Monopolar and Bipolar Transurethral Resection of Bladder Tumor: A Randomized Trial.

    Science.gov (United States)

    Teoh, Jeremy Yuen-Chun; Chan, Eddie Shu-Yin; Yip, Siu-Ying; Tam, Ho-Man; Chiu, Peter Ka-Fung; Yee, Chi-Hang; Wong, Hon-Ming; Chan, Chi-Kwok; Hou, Simon See-Ming; Ng, Chi-Fai

    2017-05-01

    Our aim was to investigate the detrusor muscle sampling rate after monopolar versus bipolar transurethral resection of bladder tumor (TURBT). This was a single-center, prospective, randomized, phase III trial on monopolar versus bipolar TURBT. Baseline patient characteristics, disease characteristics and perioperative outcomes were compared, with the primary outcome being the detrusor muscle sampling rate in the TURBT specimen. Multivariate logistic regression analyses on detrusor muscle sampling were performed. From May 2012 to December 2015, a total of 160 patients with similar baseline characteristics were randomized to receive monopolar or bipolar TURBT. Fewer patients in the bipolar TURBT group required postoperative irrigation than patients in the monopolar TURBT group (18.7 vs. 43%; p = 0.001). In the whole cohort, no significant difference in the detrusor muscle sampling rates was observed between the bipolar and monopolar TURBT groups (77.3 vs. 63.3%; p = 0.057). In patients with urothelial carcinoma, bipolar TURBT achieved a higher detrusor muscle sampling rate than monopolar TURBT (84.6 vs. 67.7%; p = 0.025). On multivariate analyses, bipolar TURBT (odds ratio [OR] 2.23, 95% confidence interval [CI] 1.03-4.81; p = 0.042) and larger tumor size (OR 1.04, 95% CI 1.01-1.08; p = 0.022) were significantly associated with detrusor muscle sampling in the whole cohort. In addition, bipolar TURBT (OR 2.88, 95% CI 1.10-7.53; p = 0.031), larger tumor size (OR 1.05, 95% CI 1.01-1.10; p = 0.035), and female sex (OR 3.25, 95% CI 1.10-9.59; p = 0.033) were significantly associated with detrusor muscle sampling in patients with urothelial carcinoma. There was a trend towards a superior detrusor muscle sampling rate after bipolar TURBT. Further studies are needed to determine its implications on disease recurrence and progression.

  15. Young adults' trajectories of Ecstasy use: a population based study.

    Science.gov (United States)

    Smirnov, Andrew; Najman, Jake M; Hayatbakhsh, Reza; Plotnikova, Maria; Wells, Helene; Legosz, Margot; Kemp, Robert

    2013-11-01

    Young adults' Ecstasy use trajectories have important implications for individual and population-level consequences of Ecstasy use, but little relevant research has been conducted. This study prospectively examines Ecstasy trajectories in a population-based sample. Data are from the Natural History Study of Drug Use, a retrospective/prospective cohort study conducted in Australia. Population screening identified a probability sample of Ecstasy users aged 19-23 years. Complete data for 30 months of follow-up, comprising 4 time intervals, were available for 297 participants (88.4% of sample). Trajectories were derived using cluster analysis based on recent Ecstasy use at each interval. Trajectory predictors were examined using a generalized ordered logit model and included Ecstasy dependence (World Mental Health Composite International Diagnostic Instrument), psychological distress (Hospital Anxiety Depression Scale), aggression (Young Adult Self Report) and contextual factors (e.g. attendance at electronic/dance music events). Three Ecstasy trajectories were identified (low, intermediate and high use). At its peak, the high-use trajectory involved 1-2 days Ecstasy use per week. Decreasing frequency of use was observed for intermediate and high-use trajectories from 12 months, independently of market factors. Intermediate and high-use trajectory membership was predicted by past Ecstasy consumption (>70 pills) and attendance at electronic/dance music events. High-use trajectory members were unlikely to have used Ecstasy for more than 3 years and tended to report consistently positive subjective effects at baseline. Given the social context and temporal course of Ecstasy use, Ecstasy trajectories might be better understood in terms of instrumental rather than addictive drug use patterns. © 2013 Elsevier Ltd. All rights reserved.

  16. High-risk HPV infection after five years in a population-based cohort of Chilean women

    Directory of Open Access Journals (Sweden)

    Ferreccio Catterina

    2011-11-01

    Full Text Available Abstract Background The need to review cervical cancer prevention strategies has been triggered by the availability of new prevention tools linked to human papillomavirus (HPV: vaccines and screening tests. To consider these innovations, information on HPV type distribution and natural history is necessary. This is a five-year follow-up study of gynecological high-risk (HR HPV infection among a Chilean population-based cohort of women. Findings A population-based random sample of 969 women from Santiago, Chile aged 17 years or older was enrolled in 2001 and revisited in 2006. At both visits they answered a survey on demographics and sexual history and provided a cervical sample for HPV DNA detection (GP5+/6+ primer-mediated PCR and Reverse line blot genotyping. Follow-up was completed by 576 (59.4% women; 45 (4.6% refused participation; most losses to follow-up were women who were unreachable, no longer eligible or had missing samples. HR-HPV prevalence increased by 43%. Incidence was highest in women 70 (0%; it was three times higher among women HR-HPV positive versus HPV negative at baseline (25.5% and 8.3%; OR 3.8, 95% CI 1.8-8.0. Type-specific persistence was 35.3%; it increased with age, from 0% in women 70. An enrollment Pap result ASCUS or worse was the only risk factor for being HR-HPV positive at both visits. Conclusions HR-HPV prevalence increased in the study population. All HR-HPV infections in women 30 years.

  17. Men's health: a population-based study on social inequalities.

    Science.gov (United States)

    Bastos, Tássia Fraga; Alves, Maria Cecília Goi Porto; Barros, Marilisa Berti de Azevedo; Cesar, Chester Luiz Galvão

    2012-11-01

    This study evaluates social inequalities in health according to level of schooling in the male population. This was a cross-sectional, population-based study with a sample of 449 men ranging from 20 to 59 years of age and living in Campinas, São Paulo State, Brazil. The chi-square test was used to verify associations, and a Poisson regression model was used to estimate crude and adjusted prevalence ratios. Men with less schooling showed higher rates of alcohol consumption and dependence, smoking, sedentary lifestyle during leisure time, and less healthy eating habits, in addition to higher prevalence of bad or very bad self-rated health, at least one chronic disease, hypertension, and other health problems. No differences were detected between the two schooling strata in terms of use of health services, except for dental services. The findings point to social inequality in health-related behaviors and in some health status indicators. However, possible equity was observed in the use of nearly all types of health services.

  18. Calcium intake by adolescents: a population-based health survey

    Directory of Open Access Journals (Sweden)

    Daniela de Assumpção

    2016-06-01

    Full Text Available Abstract Objective To analyze calcium intake in adolescents according to sociodemographic variables, health-related behaviors, morbidities, and body mass index. Methods This was a cross-sectional population-based study, with a two-stage cluster sampling that used data from a survey conducted in Campinas, São Paulo, Brazil, between 2008 and 2009. Food intake was assessed using a 24-hour dietary recall. The study included 913 adolescents aged 10-19 years. Results Average nutrient intake was significantly lower in the segment with lower education of the head of the family and lower per capita family income, in individuals from other cities or states, those who consumed fruit less than four times a week, those who did not drink milk daily, those who were smokers, and those who reported the occurrence of headaches and dizziness. Higher mean calcium intake was found in individuals that slept less than seven hours a day. The prevalence of calcium intake below the recommendation was 88.6% (95% CI: 85.4-91.2. Conclusion The results alert to an insufficient calcium intake and suggest that certain subgroups of adolescents need specific strategies to increase the intake of this nutrient.

  19. Calcium intake by adolescents: a population-based health survey.

    Science.gov (United States)

    de Assumpção, Daniela; Dias, Marcia Regina Messaggi Gomes; de Azevedo Barros, Marilisa Berti; Fisberg, Regina Mara; de Azevedo Barros Filho, Antonio

    2016-01-01

    To analyze calcium intake in adolescents according to sociodemographic variables, health-related behaviors, morbidities, and body mass index. This was a cross-sectional population-based study, with a two-stage cluster sampling that used data from a survey conducted in Campinas, São Paulo, Brazil, between 2008 and 2009. Food intake was assessed using a 24-hour dietary recall. The study included 913 adolescents aged 10-19 years. Average nutrient intake was significantly lower in the segment with lower education of the head of the family and lower per capita family income, in individuals from other cities or states, those who consumed fruit less than four times a week, those who did not drink milk daily, those who were smokers, and those who reported the occurrence of headaches and dizziness. Higher mean calcium intake was found in individuals that slept less than seven hours a day. The prevalence of calcium intake below the recommendation was 88.6% (95% CI: 85.4-91.2). The results alert to an insufficient calcium intake and suggest that certain subgroups of adolescents need specific strategies to increase the intake of this nutrient. Copyright © 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  20. Determining optimal sample sizes for multistage adaptive randomized clinical trials from an industry perspective using value of information methods.

    Science.gov (United States)

    Chen, Maggie H; Willan, Andrew R

    2013-02-01

    Most often, sample size determinations for randomized clinical trials are based on frequentist approaches that depend on somewhat arbitrarily chosen factors, such as type I and II error probabilities and the smallest clinically important difference. As an alternative, many authors have proposed decision-theoretic (full Bayesian) approaches, often referred to as value of information methods that attempt to determine the sample size that maximizes the difference between the trial's expected utility and its expected cost, referred to as the expected net gain. Taking an industry perspective, Willan proposes a solution in which the trial's utility is the increase in expected profit. Furthermore, Willan and Kowgier, taking a societal perspective, show that multistage designs can increase expected net gain. The purpose of this article is to determine the optimal sample size using value of information methods for industry-based, multistage adaptive randomized clinical trials, and to demonstrate the increase in expected net gain realized. At the end of each stage, the trial's sponsor must decide between three actions: continue to the next stage, stop the trial and seek regulatory approval, or stop the trial and abandon the drug. A model for expected total profit is proposed that includes consideration of per-patient profit, disease incidence, time horizon, trial duration, market share, and the relationship between trial results and probability of regulatory approval. The proposed method is extended to include multistage designs with a solution provided for a two-stage design. An example is given. Significant increases in the expected net gain are realized by using multistage designs. The complexity of the solutions increases with the number of stages, although far simpler near-optimal solutions exist. The method relies on the central limit theorem, assuming that the sample size is sufficiently large so that the relevant statistics are normally distributed. From a value of

  1. Uncertainty Of Stream Nutrient Transport Estimates Using Random Sampling Of Storm Events From High Resolution Water Quality And Discharge Data

    Science.gov (United States)

    Scholefield, P. A.; Arnscheidt, J.; Jordan, P.; Beven, K.; Heathwaite, L.

    2007-12-01

    The uncertainties associated with stream nutrient transport estimates are frequently overlooked and the sampling strategy is rarely if ever investigated. Indeed, the impact of sampling strategy and estimation method on the bias and precision of stream phosphorus (P) transport calculations is little understood despite the use of such values in the calibration and testing of models of phosphorus transport. The objectives of this research were to investigate the variability and uncertainty in the estimates of total phosphorus transfers at an intensively monitored agricultural catchment. The Oona Water which is located in the Irish border region, is part of a long term monitoring program focusing on water quality. The Oona Water is a rural river catchment with grassland agriculture and scattered dwelling houses and has been monitored for total phosphorus (TP) at 10 min resolution for several years (Jordan et al, 2007). Concurrent sensitive measurements of discharge are also collected. The water quality and discharge data were provided at 1 hour resolution (averaged) and this meant that a robust estimate of the annual flow weighted concentration could be obtained by simple interpolation between points. A two-strata approach (Kronvang and Bruhn, 1996) was used to estimate flow weighted concentrations using randomly sampled storm events from the 400 identified within the time series and also base flow concentrations. Using a random stratified sampling approach for the selection of events, a series ranging from 10 through to the full 400 were used, each time generating a flow weighted mean using a load-discharge relationship identified through log-log regression and monte-carlo simulation. These values were then compared to the observed total phosphorus concentration for the catchment. Analysis of these results show the impact of sampling strategy, the inherent bias in any estimate of phosphorus concentrations and the uncertainty associated with such estimates. The

  2. Global Stratigraphy of Venus: Analysis of a Random Sample of Thirty-Six Test Areas

    Science.gov (United States)

    Basilevsky, Alexander T.; Head, James W., III

    1995-01-01

    The age relations between 36 impact craters with dark paraboloids and other geologic units and structures at these localities have been studied through photogeologic analysis of Magellan SAR images of the surface of Venus. Geologic settings in all 36 sites, about 1000 x 1000 km each, could be characterized using only 10 different terrain units and six types of structures. These units and structures form a major stratigraphic and geologic sequence (from oldest to youngest): (1) tessera terrain; (2) densely fractured terrains associated with coronae and in the form of remnants among plains; (3) fractured and ridged plains and ridge belts; (4) plains with wrinkle ridges; (5) ridges associated with coronae annulae and ridges of arachnoid annulae which are contemporary with wrinkle ridges of the ridged plains; (6) smooth and lobate plains; (7) fractures of coronae annulae, and fractures not related to coronae annulae, which disrupt ridged and smooth plains; (8) rift-associated fractures; and (9) craters with associated dark paraboloids, which represent the youngest 1O% of the Venus impact crater population (Campbell et al.), and are on top of all volcanic and tectonic units except the youngest episodes of rift-associated fracturing and volcanism; surficial streaks and patches are approximately contemporary with dark-paraboloid craters. Mapping of such units and structures in 36 randomly distributed large regions (each approximately 10(exp 6) sq km) shows evidence for a distinctive regional and global stratigraphic and geologic sequence. On the basis of this sequence we have developed a model that illustrates several major themes in the history of Venus. Most of the history of Venus (that of its first 80% or so) is not preserved in the surface geomorphological record. The major deformation associated with tessera formation in the period sometime between 0.5-1.0 b.y. ago (Ivanov and Basilevsky) is the earliest event detected. In the terminal stages of tessera fon

  3. Use of pornography in a random sample of Norwegian heterosexual couples.

    Science.gov (United States)

    Daneback, Kristian; Traeen, Bente; Månsson, Sven-Axel

    2009-10-01

    This study examined the use of pornography in couple relationships to enhance the sex-life. The study contained a representative sample of 398 heterosexual couples aged 22-67 years. Data collection was carried out by self-administered postal questionnaires. The majority (77%) of the couples did not report any kind of pornography use to enhance the sex-life. In 15% of the couples, both had used pornography; in 3% of the couples, only the female partner had used pornography; and, in 5% of the couples, only the male partner had used pornography for this purpose. Based on the results of a discriminant function analysis, it is suggested that couples where one or both used pornography had a more permissive erotic climate compared to the couples who did not use pornography. In couples where only one partner used pornography, we found more problems related to arousal (male) and negative (female) self-perception. These findings could be of importance for clinicians who work with couples.

  4. Interim Feed The Future Population Based Assessment of Cambodia

    Data.gov (United States)

    US Agency for International Development — This is the interim population based survey of Feed the Future in Cambodia for 2015. The data is split into survey modules. Modules A through C includes location...

  5. Beta Blockers and Breast Cancer Mortality: A Population- Based Study

    National Research Council Canada - National Science Library

    Thomas I. Barron; Roisin M. Connolly; Linda Sharp; Kathleen Bennett; Kala Visvanathan

    2011-01-01

    .... A series of population-based observational studies were conducted to examine associations between beta blocker use and breast tumor characteristics at diagnosis or breast cancer-specific mortality...

  6. Population-based study of epilepsy in Cambodia associated factors, measures of impact, stigma, quality of life, knowledge-attitude-practice, and treatment gap

    National Research Council Canada - National Science Library

    Bhalla, Devender; Chea, Kimly; Hun, Chamroeun; Vannareth, Mey; Huc, Pierre; Chan, Samleng; Sebbag, Robert; Gérard, Daniel; Dumas, Michel; Oum, Sophal; Druet-Cabanac, Michel; Preux, Pierre-Marie

    2012-01-01

    ...), knowledge-attitude-practice (KAP) and treatment gap in Prey Veng, Cambodia. This first Cambodian population-based case-control study had 96 epileptologist-confirmed epilepsy cases and 192 randomly selected matched healthy controls...

  7. Tobacco habits and risk of lung, oropharyngeal and oral cavity cancer: a population-based case-control study in Bhopal, India

    National Research Council Canada - National Science Library

    Dikshit, R P; Kanhere, S

    2000-01-01

    .... In all, 163 lung, 247 oropharyngeal and 148 oral cavity cancer cases from the Population-Based Cancer Registry records and 260 controls randomly selected from a tobacco survey conducted in the Bhopal...

  8. Excessive daytime sleepiness is associated with an exacerbation of migraine: A population-based study.

    Science.gov (United States)

    Kim, Jiyoung; Cho, Soo-Jin; Kim, Won-Joo; Yang, Kwang Ik; Yun, Chang-Ho; Chu, Min Kyung

    2016-12-01

    Previous studies have shown that migraine and sleep disturbances are closely associated. Excessive daytime sleepiness (EDS) is a common symptom of various types of sleep disturbance. Findings from clinic-based studies suggest that a high percentage of migraineurs experience EDS. However, the prevalence and clinical impact of EDS among migraineurs at the population level have rarely been reported. The objective of this study was to investigate the prevalence and impact of EDS among migraineurs using a population-based sample in Korea. We selected a stratified random sample of Koreans aged 19 to 69 years and evaluated them using a semi-structured interview designed to identify EDS, headache type, and the clinical characteristics of migraine. If the score on the Epworth Sleepiness Scale (ESS) was more than or equal to 11, the participant was classified as having EDS. Of the 2,695 participants that completed the interview, 143 (5.3 %) and 313 (11.6 %) were classified as having migraine and EDS, respectively. The prevalence of EDS was significantly higher in participants with migraine (19.6 %) and non-migraine headache (13.4 %) compared to non-headache controls (9.4 %). Migraineurs with EDS had higher scores on the Visual Analogue Scale (VAS) for headache intensity (6.9 ± 1.8 vs. 6.0 ± 1.9, p = 0.014) and Headache Impact Test-6 (59.8 ± 10.2 vs. 52.5 ± 8.2, p migraine symptoms.

  9. Population-based study of self-reported ocular trauma in Fiji.

    Science.gov (United States)

    Brian, Garry; du Toit, Renee; Ramke, Jacqueline; Szetu, John

    2011-07-01

    To characterize causes, risk factors and outcomes for ocular trauma among adults aged ≥40 years in Fiji. Population-based cross-sectional survey; multistage cluster random sampling. 1381 (= 73.0% participation); eight provinces on Viti Levu. Interview-based questionnaire. Visual acuity measurement. Dilated ocular examination. Circumstances, management and consequences of self-reported ocular trauma. Of participants, 20.6% recalled ocular trauma: being Melanesian (P 15 years: 38.5% occurred inside the home, most by sharp objects (51.6%) and domestic violence (28.4%); agricultural activities caused 20.6% of injuries; non-agricultural workplace incidents caused 16.2%, with chemicals responsible for 27.5% of these; public alcohol consumption was associated with 13.8% of injuries, mostly by assault (91.2%). Conventional medical services were the primary source of care for 47.2% of injured participants: 61.9% attended on injury day. For trauma: sample prevalence of vision impairment in at least one eye was 1.7% (95% confidence interval 1.1-2.4%), and 0.1% (95% confidence interval 0.02-0.5) for bilateral blindness. Injury at ≤15 years (P = 0.008) and at the workplace (P = 0.044) were predictive of ongoing vision impairment. Of visually impaired eyes, 36% had corneal opacity that may have been caused by relatively minor trauma. Ophthalmic service strengthening (including minor corneal trauma management) and specific injury prevention strategies (including behaviour change education and advocacy for legislation) are required to decrease the ocular trauma burden in Fiji. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.

  10. Knowledge and Awareness of Age Related Eye Diseases: a Population-Based Survey

    Directory of Open Access Journals (Sweden)

    Marzieh Katibeh

    2014-01-01

    Full Text Available Purpose: To determine general awareness and knowledge about cataracts, glaucoma and diabetic retinopathy (DR, as common avoidable causes of blindness in an Iranian population. Methods: This cross-sectional population-based survey was performed on residents over 45 years of age in Tehran. The sampling frame was the list of all landline phone numbers registered by the Telecommunications Center of Iran, through which systematic random sampling was performed. Data was collected by phone-call interviews and completing a semi-structured questionnaire. Awareness was defined as whether the respondent had ever heard of the disease. Knowledge was assessed by realizing different aspects of each disease. Results: Of a total of 1,084 eligible people including 574 (52.9% women and 510 (47.1% men were included and 957 subjects (response rate, 88.3% completed the interview. Awareness regarding glaucoma, cataract and DR was 46.6% (95% confidence interval [CI]:43.4 -49.8%, 82.9% (95% CI: 80.5 -85.3% and 86.2% (95% CI: 84-88.4%. In addition, 19.2% (95% CI: 16.7 -21.7%, 57.3% (95% CI: 54.2-60.4% and 72% (95% CI: 69.2 -74.8% of respondents could give at least a basic definition of the mentioned diseases, respectively. Only 22.6% (95% CI: 20-25.2% and 41.6% (95% CI: 38.5-44.7% realized glaucoma and DR as a treatable condition; in contrast, 77.2% (95% CI: 74.5-79.9% categorized cataract as treatable. Only 19% and 7.1% knew that DR and glaucoma may commence without any apparent symptoms. Conclusion: Compared with cataract and DR, most participants had limited information about glaucoma. In addition, few of the respondents were familiar with the initial symptoms of DR and glaucoma.

  11. Attitudes towards suicide in urban and rural China: a population based, cross-sectional study.

    Science.gov (United States)

    Zou, Yaming; Leung, Ricky; Lin, Shao; Yang, Mingan; Lu, Tao; Li, Xianyun; Gu, Jing; Hao, Chun; Dong, Guanghui; Hao, Yuantao

    2016-05-26

    Suicide intervention programs have been guided by findings that attitude towards suicide and suicidal behavior may be causally linked. These findings also make it imperative to identify the factors that influence attitudes towards suicide. However, there has been little research on attitudes towards suicide among the general population, especially in low-income and middle-income countries. This population-based, cross-sectional study investigated the associated factors of attitudes towards suicide among a representative sample of urban and rural adult residents in China. A multi-stage, stratified random sampling approach was implemented to select participants. Data were collected by a survey using the Scale of Public Attitudes about Suicide (SPAS). The survey also collected some socio-demographic factors and suicidal history of participants. Statistical tests were conducted to identify associated factors that account for variations in attitudes towards suicide. The residents in China generally hold a neutral attitude towards suicide. Attitudes towards suicide among Chinese residents were associated with age, duration of formal education, marital status, job and suicidal ideation. Different attitudinal subscales seemed not to share the same risk factors. However, gender, ethnicity, religious belief, housing style and economic status might not influence residents' attitudes towards suicide. Attitudes towards suicide among Chinese urban and rural residents generally had no statistical difference with one notable exception: opinions on whether or not suicides and suicide attempts are different phenomena. Age, duration of formal education, marital status, job and suicidal ideation seem to have an impact on attitudes towards suicide among residents. Urban and rural residents have similar attitudes towards suicide with the only statistically significance difference being their opinions on whether or not suicides and suicide attempts are different phenomena.

  12. Population-based prevalence survey of tuberculosis in the Tigray region of Ethiopia.

    Science.gov (United States)

    Berhe, Gebretsadik; Enqueselassie, Fikre; Hailu, Elena; Mekonnen, Wondale; Teklu, Tsigemariam; Gebretsadik, Ataklti; Berhe, Rezene; Haile, Tewodros; Aseffa, Abraham

    2013-09-28

    Population based prevalence survey is an important epidemiological index to measure the burden of tuberculosis (TB) disease and monitor progress towards TB control in high burden countries like Ethiopia. This study was aimed to estimate the prevalence of bacteriologically confirmed pulmonary tuberculosis (PTB) in the Tigray region of Ethiopia. Sixteen rural and urban villages were randomly selected in a stratified multistage cluster sampling. Individuals aged 15 years and older were screened by symptom inquiry for PTB. Those individuals who were symptomatic of PTB provided two sputum samples for smear microscopy, culture and molecular typing. The study covering 4,765 households screened a total of 12,175 individuals aged 15 years and above. The overall weighted prevalence of bacteriologically confirmed PTB in the Tigray region of Ethiopia was found to be 216/100,000 (95% CI: 202.08, 230.76) while the weighted prevalence of smear-positive PTB was 169/100,000 (95% CI: 155.53, 181.60). The prevalence of bacteriologically confirmed TB was higher amongst males (352/100 000; 95% CI: 339.05, 364.52) than females (162/100 000; 95% CI: 153.60, 171.17) and among rural (222/100,000; 95% CI: 212.77-231.53) as compared to urban residents (193/100,000; 95% CI: 183.39-203.59). This study found a relatively higher prevalence smear-positive PTB in the region than in a same period nationwide survey and identified a significant number of undetected PTB cases. The urgency for improved TB case detection and intensified community awareness is emphasized.

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

    Science.gov (United States)

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

    2014-01-01

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

  14. Public views of acceptability of perinatal mental health screening and treatment preference: a population based survey.

    Science.gov (United States)

    Kingston, Dawn; McDonald, Sheila; Tough, Suzanne; Austin, Marie-Paule; Hegadoren, Kathy; Lasiuk, Gerri

    2014-02-12

    At a prevalence rate of 13-25%, mental health problems are among the most common morbidities of the prenatal and postnatal periods. They have been associated with increased risk of preterm birth and low birthweight, child developmental delay, and poor child mental health. However, very few pregnant and postpartum women proactively seek help or engage in treatment and less than 15% receive needed mental healthcare. While system-related barriers limit accessibility and availability of mental health services, personal barriers, such as views of mental health and its treatment, are also cited as significant deterrents of obtaining mental healthcare. The purposes of this population-based study were to identify the public's views regarding mental health screening and treatment in pregnant and postpartum women, and to determine factors associated with those views. A computer-assisted telephone survey was conducted by the Population Research Laboratory with a random sample of adults in Alberta, Canada. Questions were drawn from the Perinatal Depression Monitor, an Australian population-based survey on perinatal mental health; additional questions were developed and tested to reflect the Canadian context. Interviews were conducted in English and were less than 30 minutes in duration. Descriptive and multivariable regression analyses were conducted. Among the 1207 respondents, 74.8% had post-secondary education, 16.3% were 18-34 years old, and two-thirds (66.1%) did not have children screened in the prenatal (63.0%) and postpartum periods (72.7%). Respondents reported that when seeking help and support their first choice would be a family doctor. Preferred treatments were talking to a doctor or midwife and counseling. Knowledge of perinatal mental health was the main factor associated with different treatment preferences. The high acceptability of universal perinatal mental health screening among the public provides a strong message regarding the public value for routine

  15. Estimating screening-mammography receiver operating characteristic (ROC) curves from stratified random samples of screening mammograms: a simulation study.

    Science.gov (United States)

    Zur, Richard M; Pesce, Lorenzo L; Jiang, Yulei

    2015-05-01

    To evaluate stratified random sampling (SRS) of screening mammograms by (1) Breast Imaging Reporting and Data System (BI-RADS) assessment categories, and (2) the presence of breast cancer in mammograms, for estimation of screening-mammography receiver operating characteristic (ROC) curves in retrospective observer studies. We compared observer study case sets constructed by (1) random sampling (RS); (2) SRS with proportional allocation (SRS-P) with BI-RADS 1 and 2 noncancer cases accounting for 90.6% of all noncancer cases; (3) SRS with disproportional allocation (SRS-D) with BI-RADS 1 and 2 noncancer cases accounting for 10%-80%; and (4) SRS-D and multiple imputation (SRS-D + MI) with missing BI-RADS 1 and 2 noncancer cases imputed to recover the 90.6% proportion. Monte Carlo simulated case sets were drawn from a large case population modeled after published Digital Mammography Imaging Screening Trial data. We compared the bias, root-mean-square error, and coverage of 95% confidence intervals of area under the ROC curve (AUC) estimates from the sampling methods (200-2000 cases, of which 25% were cancer cases) versus from the large case population. AUC estimates were unbiased from RS, SRS-P, and SRS-D + MI, but biased from SRS-D. AUC estimates from SRS-P and SRS-D + MI had 10% smaller root-mean-square error than RS. Both SRS-P and SRS-D + MI can be used to obtain unbiased and 10% more efficient estimate of screening-mammography ROC curves. Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.

  16. Randomized Comparison of Two Vaginal Self-Sampling Methods for Human Papillomavirus Detection: Dry Swab versus FTA Cartridge.

    Directory of Open Access Journals (Sweden)

    Rosa Catarino

    Full Text Available Human papillomavirus (HPV self-sampling (self-HPV is valuable in cervical cancer screening. HPV testing is usually performed on physician-collected cervical smears stored in liquid-based medium. Dry filters and swabs are an alternative. We evaluated the adequacy of self-HPV using two dry storage and transport devices, the FTA cartridge and swab.A total of 130 women performed two consecutive self-HPV samples. Randomization determined which of the two tests was performed first: self-HPV using dry swabs (s-DRY or vaginal specimen collection using a cytobrush applied to an FTA cartridge (s-FTA. After self-HPV, a physician collected a cervical sample using liquid-based medium (Dr-WET. HPV types were identified by real-time PCR. Agreement between collection methods was measured using the kappa statistic.HPV prevalence for high-risk types was 62.3% (95%CI: 53.7-70.2 detected by s-DRY, 56.2% (95%CI: 47.6-64.4 by Dr-WET, and 54.6% (95%CI: 46.1-62.9 by s-FTA. There was overall agreement of 70.8% between s-FTA and s-DRY samples (kappa = 0.34, and of 82.3% between self-HPV and Dr-WET samples (kappa = 0.56. Detection sensitivities for low-grade squamous intraepithelial lesion or worse (LSIL+ were: 64.0% (95%CI: 44.5-79.8 for s-FTA, 84.6% (95%CI: 66.5-93.9 for s-DRY, and 76.9% (95%CI: 58.0-89.0 for Dr-WET. The preferred self-collection method among patients was s-DRY (40.8% vs. 15.4%. Regarding costs, FTA card was five times more expensive than the swab (~5 US dollars (USD/per card vs. ~1 USD/per swab.Self-HPV using dry swabs is sensitive for detecting LSIL+ and less expensive than s-FTA.International Standard Randomized Controlled Trial Number (ISRCTN: 43310942.

  17. A population-based survey of the prevalence and types of glaucoma in central Iran: the Yazd eye study.

    Science.gov (United States)

    Pakravan, Mohammad; Yazdani, Shahin; Javadi, Mohammad-Ali; Amini, Heidar; Behroozi, Zohreh; Ziaei, Hossein; Katibeh, Marzieh; Solaimanizad, Reza; Ghahari, Elham; Yaseri, Mehdi

    2013-10-01

    To describe the prevalence and types of glaucoma in Yazd, central Iran. Population-based, cross-sectional study. Iranian adults aged 40 to 80 years, residing in Yazd, Iran, in 2010 and 2011. Eligible samples were selected using cluster random sampling. Each participant underwent an interview and ophthalmologic examinations, including refraction, determination of uncorrected and best-corrected visual acuity, slit-lamp biomicroscopy, Goldmann applanation tonometry, gonioscopy, dilated fundus examination, central corneal thickness measurement, visual field testing, and stereoscopic fundus photography. Prevalence of different types of glaucoma. Of 2320 eligible individuals, 2098 (response rate, 90.4%) participated in the study and 1990 completed all evaluations for glaucoma diagnosis. Overall, 47 persons (2.4%) were categorized with ocular hypertension, 32 persons (1.6%) were categorized with primary angle-closure suspect (PACS), and 16 persons (0.8%) were categorized with primary angle closure (PAC). The total number of subjects with glaucoma was 87 (4.4%; 95% confidence interval, 3.3-5.4), consisting of primary open-angle glaucoma (POAG, 3.2%, including high-tension glaucoma [1.7%] and normal-tension glaucoma [NTG], 1.5%]), primary angle-closure glaucoma (PACG, 0.4%), pseudoexfoliation glaucoma (0.4%), and other secondary glaucomas (0.4%). The mean age of subjects with glaucoma was 63.3 ± 11 years, and 57.5% of them were female. Seventy-eight individuals (89.7%) were unaware of their disease. Positive family history of glaucoma was present in 6.9% of glaucoma subjects. The prevalence of glaucoma in Yazd (4.4%) is comparable to that in other population-based studies in Asia, with POAG accounting for the majority of cases. Most affected subjects were unaware of their disease. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights

  18. Optimal Subset Selection of Time-Series MODIS Images and Sample Data Transfer with Random Forests for Supervised Classification Modelling

    Directory of Open Access Journals (Sweden)

    Fuqun Zhou

    2016-10-01

    Full Text Available Nowadays, various time-series Earth Observation data with multiple bands are freely available, such as Moderate Resolution Imaging Spectroradiometer (MODIS datasets including 8-day composites from NASA, and 10-day composites from the Canada Centre for Remote Sensing (CCRS. It is challenging to efficiently use these time-series MODIS datasets for long-term environmental monitoring due to their vast volume and information redundancy. This challenge will be greater when Sentinel 2–3 data become available. Another challenge that researchers face is the lack of in-situ data for supervised modelling, especially for time-series data analysis. In this study, we attempt to tackle the two important issues with a case study of land cover mapping using CCRS 10-day MODIS composites with the help of Random Forests’ features: variable importance, outlier identification. The variable importance feature is used to analyze and select optimal subsets of time-series MODIS imagery for efficient land cover mapping, and the outlier identification feature is utilized for transferring sample data available from one year to an adjacent year for supervised classification modelling. The results of the case study of agricultural land cover classification at a regional scale show that using only about a half of the variables we can achieve land cover classification accuracy close to that generated using the full dataset. The proposed simple but effective solution of sample transferring could make supervised modelling possible for applications lacking sample data.

  19. Optimal Subset Selection of Time-Series MODIS Images and Sample Data Transfer with Random Forests for Supervised Classification Modelling.

    Science.gov (United States)

    Zhou, Fuqun; Zhang, Aining

    2016-10-25

    Nowadays, various time-series Earth Observation data with multiple bands are freely available, such as Moderate Resolution Imaging Spectroradiometer (MODIS) datasets including 8-day composites from NASA, and 10-day composites from the Canada Centre for Remote Sensing (CCRS). It is challenging to efficiently use these time-series MODIS datasets for long-term environmental monitoring due to their vast volume and information redundancy. This challenge will be greater when Sentinel 2-3 data become available. Another challenge that researchers face is the lack of in-situ data for supervised modelling, especially for time-series data analysis. In this study, we attempt to tackle the two important issues with a case study of land cover mapping using CCRS 10-day MODIS composites with the help of Random Forests' features: variable importance, outlier identification. The variable importance feature is used to analyze and select optimal subsets of time-series MODIS imagery for efficient land cover mapping, and the outlier identification feature is utilized for transferring sample data available from one year to an adjacent year for supervised classification modelling. The results of the case study of agricultural land cover classification at a regional scale show that using only about a half of the variables we can achieve land cover classification accuracy close to that generated using the full dataset. The proposed simple but effective solution of sample transferring could make supervised modelling possible for applications lacking sample data.

  20. Media Use and Source Trust among Muslims in Seven Countries: Results of a Large Random Sample Survey

    Directory of Open Access Journals (Sweden)

    Steven R. Corman

    2013-12-01

    Full Text Available Despite the perceived importance of media in the spread of and resistance against Islamist extremism, little is known about how Muslims use different kinds of media to get information about religious issues, and what sources they trust when doing so. This paper reports the results of a large, random sample survey among Muslims in seven countries Southeast Asia, West Africa and Western Europe, which helps fill this gap. Results show a diverse set of profiles of media use and source trust that differ by country, with overall low trust in mediated sources of information. Based on these findings, we conclude that mass media is still the most common source of religious information for Muslims, but that trust in mediated information is low overall. This suggests that media are probably best used to persuade opinion leaders, who will then carry anti-extremist messages through more personal means.

  1. Enhancing positive parent-child interactions and family functioning in a poverty sample: a randomized control trial.

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    Negrão, Mariana; Pereira, Mariana; Soares, Isabel; Mesman, Judi

    2014-01-01

    This study tested the attachment-based intervention program Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD) in a randomized controlled trial with poor families of toddlers screened for professional's concerns about the child's caregiving environment. The VIPP-SD is an evidence-based intervention, but has not yet been tested in the context of poverty. The sample included 43 families with 1- to 4-year-old children: mean age at the pretest was 29 months and 51% were boys. At the pretest and posttest, mother-child interactions were observed at home, and mothers reported on family functioning. The VIPP-SD proved to be effective in enhancing positive parent-child interactions and positive family relations in a severely deprived context. Results are discussed in terms of implications for support services provided to such poor families in order to reduce intergenerational risk transmission.

  2. Rationale, Design, Samples, and Baseline Sun Protection in a Randomized Trial on a Skin Cancer Prevention Intervention in Resort Environments

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    Buller, David B.; Andersen, Peter A.; Walkosz, Barbara J.; Scott, Michael D.; Beck, Larry; Cutter, Gary R.

    2016-01-01

    Introduction Exposure to solar ultraviolet radiation during recreation is a risk factor for skin cancer. A trial evaluating an intervention to promote advanced sun protection (sunscreen pre-application/reapplication; protective hats and clothing; use of shade) during vacations. Materials and Methods Adult visitors to hotels/resorts with outdoor recreation (i.e., vacationers) participated in a group-randomized pretest-posttest controlled quasi-experimental design in 2012–14. Hotels/resorts were pair-matched and randomly assigned to the intervention or untreated control group. Sun protection (e.g., clothing, hats, shade and sunscreen) was measured in cross-sectional samples by observation and a face-to-face intercept survey during two-day visits. Results Initially, 41 hotel/resorts (11%) participated but 4 dropped out before posttest. Hotel/resorts were diverse (employees=30 to 900; latitude=24o 78′ N to 50o 52′ N; elevation=2 ft. to 9,726 ft. above sea level), and had a variety of outdoor venues (beaches/pools, court/lawn games, golf courses, common areas, and chairlifts). At pretest, 4,347 vacationers were observed and 3,531 surveyed. More females were surveyed (61%) than observed (50%). Vacationers were mostly 35–60 years old, highly educated (college education = 68%) and non-Hispanic white (93%), with high-risk skin types (22%). Vacationers reported covering 60% of their skin with clothing. Also, 40% of vacationers used shade; 60% applied sunscreen; and 42% had been sunburned. Conclusions The trial faced challenges recruiting resorts but result show that the large, multi-state sample of vacationers were at high risk for solar UV exposure. PMID:26593781

  3. Investigating causal associations between use of nicotine, alcohol, caffeine, and cannabis: A two-sample bidirectional Mendelian randomization study.

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    Verweij, Karin J H; Treur, Jorien L; Vink, Jacqueline M

    2018-01-15

    Epidemiological studies consistently show co-occurrence of use of different addictive substances. Whether these associations are causal or due to overlapping underlying influences remains an important question in addiction research. Methodological advances have made it possible to use published genetic associations to infer causal relationships between phenotypes. In this exploratory study, we used Mendelian randomization (MR) to examine the causality of well-established associations between nicotine, alcohol, caffeine, and cannabis use. Two-sample MR was employed to estimate bi-directional causal effects between four addictive substances: nicotine (smoking initiation and cigarettes smoked per day), caffeine (cups of coffee per day), alcohol (units per week), and cannabis (initiation). Based on existing genome-wide association results we selected genetic variants associated with the exposure measure as an instrument to estimate causal effects. Where possible we applied sensitivity analyses (MR-Egger and weighted median) more robust to horizontal pleiotropy. Most MR tests did not reveal causal associations. There was some weak evidence for a causal positive effect of genetically instrumented alcohol use on smoking initiation and of cigarettes per day on caffeine use, but these did not hold up with the sensitivity analyses. There was also some suggestive evidence for a positive effect of alcohol use on caffeine use (only with MR-Egger) and smoking initiation on cannabis initiation (only with weighted median). None of the suggestive causal associations survived corrections for multiple testing. Two-sample Mendelian randomization analyses found little evidence for causal relationships between nicotine, alcohol, caffeine, and cannabis use. This article is protected by copyright. All rights reserved.

  4. Sleep and Multisystem Biological Risk: A Population-Based Study

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    Carroll, Judith E.; Irwin, Michael R.; Merkin, Sharon Stein; Seeman, Teresa E.

    2015-01-01

    Background Short sleep and poor sleep quality are associated with risk of cardiovascular disease, diabetes, cancer, and mortality. This study examines the contribution of sleep duration and sleep quality on a multisystem biological risk index that is known to be associated with morbidity and mortality. Methods Analyses include a population-based sample from the Midlife Development in the United States survey recruited to the Biomarker substudy. A total of 1,023 participants aged 54.5 years (SD = 11.8), 56% female and 77.6% white, were included in the analyses. A multisystem biological risk index was derived from 22 biomarkers capturing cardiovascular, immune, lipid-metabolic, glucose-metabolic, sympathetic, parasympathetic, and hypothalamic-pituitary-adrenal systems. Self-reported average sleep duration was categorized as short (Sleep quality was determined using the Pittsburgh Sleep Quality Index categorized as normal (≤5) and poor quality (>5) sleep. Findings Linear mixed effect models adjusting for age, gender, race, education, income, BMI, and health status were performed. As compared to normal sleepers, multisystem biological risk in both short (B(SE) = .38(.15), pPoor quality sleep alone was associated with elevated multisystem biological risk (B(SE) = .15(.06), p = .01), but was not significant after adjustment for health status. All short sleepers reported poor sleep quality. However in the long sleepers, only those who reported poor sleep quality exhibited elevated multisystem biological risk (B(SE) = .93(.3), p = .002). Conclusions Self-reported poor sleep quality with either short or long sleep duration is associated with dysregulation in physiological set points across regulatory systems, leading to elevated multisystem biological risk. Physicians should inquire about sleep health in the assessment of lifestyle factors related to disease risk, with evidence that healthy sleep is associated with lower multisystem biological risk. PMID:25714703

  5. Burden of valvular heart diseases: a population-based study.

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    Nkomo, Vuyisile T; Gardin, Julius M; Skelton, Thomas N; Gottdiener, John S; Scott, Christopher G; Enriquez-Sarano, Maurice

    2006-09-16

    Valvular heart diseases are not usually regarded as a major public-health problem. Our aim was to assess their prevalence and effect on overall survival in the general population. We pooled population-based studies to obtain data for 11 911 randomly selected adults from the general population who had been assessed prospectively with echocardiography. We also analysed data from a community study of 16 501 adults who had been assessed by clinically indicated echocardiography. In the general population group, moderate or severe valve disease was identified in 615 adults. There was no difference in the frequency of such diseases between men and women (p=0.90). Prevalence increased with age, from 0.7% (95% CI 0.5-1.0) in 18-44 year olds to 13.3% (11.7-15.0) in the 75 years and older group (p<0.0001). The national prevalence of valve disease, corrected for age and sex distribution from the US 2000 population, is 2.5% (2.2-2.7). In the community group, valve disease was diagnosed in 1505 (1.8% adjusted) adults and frequency increased considerably with age, from 0.3% (0.2-0.3) of the 18-44 year olds to 11.7% (11.0-12.5) of those aged 75 years and older, but was diagnosed less often in women than in men (odds ratio 0.90, 0.81-1.01; p=0.07). The adjusted mortality risk ratio associated with valve disease was 1.36 (1.15-1.62; p=0.0005) in the population and 1.75 (1.61-1.90; p<0.0001) in the community. Moderate or severe valvular diseases are notably common in this population and increase with age. In the community, women are less often diagnosed than are men, which could indicate an important imbalance in view of the associated lower survival. Valve diseases thus represent an important public-health problem.

  6. The prevalence of glaucoma in a population-based study of Hispanic subjects: Proyecto VER.

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    Quigley, H A; West, S K; Rodriguez, J; Munoz, B; Klein, R; Snyder, R

    2001-12-01

    To determine the prevalence of glaucoma in a population-based sample of Hispanic adults older than 40 years. Using 1990 census data for Arizona, groups of persons living in sections of the city in Nogales and Tucson were randomly selected with a probability proportional to the Hispanic population older than 40 years. We tried to recruit all eligible adults in homes with 1 self-described Hispanic adult. Detailed ocular examinations at a local clinic included visual acuity testing, applanation tonometry, gonioscopy, an optic disc evaluation, and a threshold visual field test. Open-angle glaucoma (OAG) was defined using a proposed international system for prevalence surveys, including threshold visual field defect and optic disc damage. Angle-closure glaucoma was defined as bilateral appositional angle closure, combined with optic nerve damage (judged by field and disc as for OAG). Examinations were conducted in 72% (4774/6658) of eligible persons, with a 1.97% prevalence (95% confidence interval, 1.58%-2.36%) of OAG (94 persons). The age-specific OAG prevalence increased nonlinearly from 0.50% in those aged 41 to 49 years to 12.63% in those 80 years and older. Angle-closure glaucoma was detected in 5 persons (0.10%). Sex, blood pressure, and cigarette smoking were not significant OAG risk factors. Only 36 (38%) of the 94 persons with OAG were aware of their OAG before the study. Screening results with an intraocular pressure higher than 22 mm Hg (in the eye with a higher pressure) would miss 80% of the OAG cases. The prevalence of OAG in Hispanic persons was intermediate between reported values for white and black persons. The prevalence increased more quickly with increasing age than in other ethnic groups. Glaucoma was the leading cause of bilateral blindness.

  7. Medication adherence in type 2 diabetes: the ENTRED study 2007, a French Population-Based Study.

    Directory of Open Access Journals (Sweden)

    Michel Tiv

    Full Text Available BACKGROUND: Adherence to prescribed medications is a key dimension of healthcare quality. The aim of this large population-based study was to evaluate self-reported medication adherence and to identify factors linked with poor adherence in patients with type 2 diabetes in France. METHODOLOGY: The ENTRED study 2007, a French national survey of people treated for diabetes, was based on a representative sample of patients who claimed reimbursement for oral hypoglycaemic agents and/or insulin at least three times between August 2006 and July 2007, and who were randomly selected from the database of the two main National Health Insurance Systems. Medication adherence was determined using a six-item self-administered questionnaire. A multinomial polychotomous logistic regression model was used to identify factors associated with medication adherence in the 3,637 persons with type 2 diabetes. PRINCIPAL FINDINGS: Thirty nine percent of patients reported good medication adherence, 49% medium adherence and 12% poor adherence. The factors significantly associated with poor adherence in multivariate analysis were socio-demographic factors: age 8% and existing diabetes complications; and health care-related factors: difficulties for taking medication alone, decision making by the patient only, poor acceptability of medical recommendations, lack of family or social support, need for information on treatment, reporting no confidence in the future, need for medical support and follow-up by a specialist physician. CONCLUSIONS: In a country with a high level of access to healthcare, our study demonstrated a substantial low level of medication adherence in type 2 diabetic patients. Better identification of those with poor adherence and individualised suitable recommendations remain essential for better healthcare management.

  8. Family history and stroke outcome in a bi-ethnic, population-based stroke surveillance study

    Directory of Open Access Journals (Sweden)

    Uchino Ken

    2005-10-01

    Full Text Available Background The genetic epidemiology of ischemic stroke remains relatively unstudied, and information about the genetic epidemiology of ischemic stroke in populations with significant minority representation is currently unavailable. Methods The Brain Attack Surveillance in Corpus Christi project (BASIC is a population-based stroke surveillance study conducted in the bi-ethnic community of Nueces County, Texas, USA. Completed ischemic strokes were identified among patients 45 years or older seen at hospitals in the county between January 1, 2000 – December 31, 2002. A random sample of ischemic stroke patients underwent an in-person interview and detailed medical record abstraction (n = 400. Outcomes, including initial stroke severity (NIH stroke scale, age at stroke onset, 90-day mortality and functional outcome (modified Rankin scale ≥2, were studied for their association with family history of stroke among a first degree relative using multivariable logistic and linear regression. A chi-square test was used to test the association between family history of stroke and ischemic stroke subtype. Results The study population was 53.0% Mexican American and 58.4% female. Median age was 73.2 years. Forty percent reported a family history of stroke among a first degree relative. Family history of stroke was borderline significantly associated with stroke subtype (p = 0.0563. Family history was associated with poor functional outcome in the multivariable model (OR = 1.87; 95% CI: 1.14–3.09. Family history was not significantly related to initial stroke severity, age at stroke onset, or 90-day mortality. Conclusion Family history of stroke was related to ischemic stroke subtype and to functional status at discharge. More research is needed to understand whether stroke subtype would be a useful selection criterion for genetic association studies and to hypothesize about a possible genetic link to recovery following ischemic stroke.

  9. LONG TERM SURVIVAL FOLLOWING TRAUMATIC BRAIN INJURY: A POPULATION BASED PARAMETRIC SURVIVAL ANALYSIS

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    Fuller, Gordon Ward; Ransom, Jeanine; Mandrekar, Jay; Brown, Allen W

    2017-01-01

    Background Long term mortality may be increased following traumatic brain injury (TBI); however the degree to which survival could be reduced is unknown. We aimed to model life expectancy following post-acute TBI to provide predictions of longevity and quantify differences in survivorship with the general population. Methods A population based retrospective cohort study using data from the Rochester Epidemiology Project (REP) was performed. A random sample of patients from Olmsted County, Minnesota with a confirmed TBI between 1987 and 2000 was identified and vital status determined in 2013. Parametric survival modelling was then used to develop a model to predict life expectancy following TBI conditional on age at injury. Survivorship following TBI was also compared with the general population and age and gender matched non-head injured REP controls. Results 769 patients were included in complete case analyses. Median follow up time was 16.1 years (IQR 9.0–20.4) with 120 deaths occurring in the cohort during the study period. Survival after acute TBI was well represented by a Gompertz distribution. Victims of TBI surviving for at least 6 months post-injury demonstrated a much higher ongoing mortality rate compared to the US general population and non-TBI controls (hazard ratio 1·47, 95% CI 1·15–1·87). US general population cohort life table data was used to update the Gompertz model’s shape and scale parameters to account for cohort effects and allow prediction of life expectancy in contemporary TBI. Conclusions Survivors of TBI have decreased life expectancy compared to the general population. This may be secondary to the head injury itself or result from patient characteristics associated with both the propensity for TBI and increased early mortality. Post-TBI life expectancy estimates may be useful to guide prognosis, in public health planning, for actuarial applications and in the extrapolation of outcomes for TBI economic models. PMID:27165161

  10. The Global Trachoma Mapping Project: Methodology of a 34-Country Population-Based Study

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    Solomon, Anthony W.; Pavluck, Alexandre L.; Courtright, Paul; Aboe, Agatha; Adamu, Liknaw; Alemayehu, Wondu; Alemu, Menbere; Alexander, Neal D. E.; Kello, Amir Bedri; Bero, Berhanu; Brooker, Simon J.; Chu, Brian K.; Dejene, Michael; Emerson, Paul M.; Flueckiger, Rebecca M.; Gadisa, Solomon; Gass, Katherine; Gebre, Teshome; Habtamu, Zelalem; Harvey, Erik; Haslam, Dominic; King, Jonathan D.; Mesurier, Richard Le; Lewallen, Susan; Lietman, Thomas M.; MacArthur, Chad; Mariotti, Silvio P.; Massey, Anna; Mathieu, Els; Mekasha, Addis; Millar, Tom; Mpyet, Caleb; Muñoz, Beatriz E.; Ngondi, Jeremiah; Ogden, Stephanie; Pearce, Joseph; Sarah, Virginia; Sisay, Alemayehu; Smith, Jennifer L.; Taylor, Hugh R.; Thomson, Jo; West, Sheila K.; Willis, Rebecca; Bush, Simon; Haddad, Danny; Foster, Allen

    2015-01-01

    ABSTRACT Purpose: To complete the baseline trachoma map worldwide by conducting population-based surveys in an estimated 1238 suspected endemic districts of 34 countries. Methods: A series of national and sub-national projects owned, managed and staffed by ministries of health, conduct house-to-house cluster random sample surveys in evaluation units, which generally correspond to “health district” size: populations of 100,000–250,000 people. In each evaluation unit, we invite all residents aged 1 year and older from h households in each of c clusters to be examined for clinical signs of trachoma, where h is the number of households that can be seen by 1 team in 1 day, and the product h × c is calculated to facilitate recruitment of 1019 children aged 1–9 years. In addition to individual-level demographic and clinical data, household-level water, sanitation and hygiene data are entered into the purpose-built LINKS application on Android smartphones, transmitted to the Cloud, and cleaned, analyzed and ministry-of-health-approved via a secure web-based portal. The main outcome measures are the evaluation unit-level prevalence of follicular trachoma in children aged 1–9 years, prevalence of trachomatous trichiasis in adults aged 15 + years, percentage of households using safe methods for disposal of human feces, and percentage of households with proximate access to water for personal hygiene purposes. Results: In the first year of fieldwork, 347 field teams commenced work in 21 projects in 7 countries. Conclusion: With an approach that is innovative in design and scale, we aim to complete baseline mapping of trachoma throughout the world in 2015. PMID:26158580

  11. Dietary Patterns Associated with Alzheimer’s Disease: Population Based Study

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    Katarzyna Gustaw-Rothenberg

    2009-04-01

    Full Text Available Recently dietary pattern analysis has emerged as a way for examining diet-disease relations in Alzheimer’s disease. In contrast with the conventional approach, which focuses on a single nutrient or a few nutrients or foods, this method considers overall eating patterns. We examined the dietary patterns defined by factor analysis using data collected with a food-frequency questionnaire in people with Alzheimer’s disease (AD as compared to healthy controls. The diet data were obtained during population based study of the prevalence of Alzheimer’s disease in a population in Poland. Stratified sampling and random selection strategies were combined to obtain a representative population for screening (age group > 55. From the population screened three times, 71 people were diagnosed with Alzheimer’s according to DSM-IV, and were recruited for further diet risk factors assessment. A group of people with Alzheimer disease (n = 71; F/M 42/29 and the same number of healthy, age and gender matched control were recruited for the study. Patients and their caregivers as well as controls were presented with a food frequency questionnaire based on the 12 food groups. Factor analysis (principal component was used to derive food patterns. The analysis was conducted using the factor procedure. The factors were rotated by an orthogonal transformation (Varimax rotation to achieve simpler structure with greater interpretability. Using factor analysis, we identified major eating patterns, one for Alzheimer’s patients and a different one for control group. The AD dietary pattern, FACTOR AD was characterized by a high intake of meat, butter, high-fat dairy products, eggs, and refined sugar, whereas the other pattern, (FACTOR C was characterized by a high intake of grains and vegetables. These data indicate the existence of dietary patterns defined by factor analysis with data from a food frequency questionnaire, characteristic for Alzheimer’s disease in a

  12. Menopause and modifiable coronary heart disease risk factors: a population based study.

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    Agrinier, N; Cournot, M; Dallongeville, J; Arveiler, D; Ducimetière, P; Ruidavets, J-B; Ferrières, J

    2010-03-01

    The aim of our study was to determine the effect of the menopause on various coronary heart disease (CHD) risk factors and on the global risk of CHD in a population based sample of women, making the difference between menopause and age related effects. The Third French MONICA cross-sectional survey on cardiovascular risk included 1730 randomly selected women, aged 35-64 years, representative from the general population. Women were defined as post-menopausal (postM; n=696), peri-menopausal (periM; n=183) or pre-menopausal (preM; n=659) based on the date of last menses. Socio-demographic, clinical and biological data were collected. Analyses of variance were used to compare means. PostM women had significantly higher age-adjusted levels of total cholesterol (6.0mmol/L in postM vs. 5.7mmol/L in preM, p<0.05) and LDL cholesterol (3.9mmol/L vs. 3.6mmol/L, p<0.05). There was no difference in HDL cholesterol or triglyceride levels, glycemia or blood pressure. Further adjustment on body mass index and hormonal treatments did not modify the results. No risk factor was significantly different between periM and postM. However, the Framingham 10-year risk of CHD was higher in postM, as compared with periM (5.1% vs. 5.0%, p<0.05). In postM women, lipids and the Framingham risk were not associated with elapsed time since menopause. The CHD risk increases during the sixth decade could be explained not only by estrogen deprivation but also by an effect on lipid profile, which is likely to occur in the peri-menopause period. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

  13. Alcohol drinking pattern and subjective health in a population-based study.

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    Stranges, Saverio; Notaro, James; Freudenheim, Jo L; Calogero, Rachel M; Muti, Paola; Farinaro, Eduardo; Russell, Marcia; Nochajski, Thomas H; Trevisan, Maurizio

    2006-09-01

    Some patterns of alcohol consumption (e.g. binge drinking, drinking outside of meals) have been associated with detrimental effects on health outcomes. Subjective health provides a global assessment of health status and is a strong predictor of total mortality; however, little is known about its relationship with alcohol drinking pattern. The association between several drinking patterns (i.e. drinking intensity and frequency, frequency of intoxication, drinking outside of meals, and beverage type) and subjective health was examined in a random sample of 3586 women and men. A population-based cross-sectional study. Subjective health was assessed using the physical and mental health component summaries of the Short Form-36 health survey questionnaire. Alcohol consumption refers to the 30 days before the interview. Analysis of covariance compared gender-specific mean scores across alcohol drinking patterns. Overall, non-current drinkers reported poorer physical and mental health than life-time abstainers and current drinkers, while no consistent differences were found between life-time abstainers and current drinkers. In female current drinkers, daily drinking, beer and mixed beverage consumption were associated with better mental health. In male current drinkers, moderate alcohol consumption (2-2.9 drinks per day), wine and mixed beverage consumption were associated with better physical health. Intoxication and liquor consumption were associated with poorer mental health in women and poorer physical health in men. No consistent associations were found for drinking outside meals. Aspects of drinking pattern may affect subjective health differentially in women and men. Overall, intoxication and liquor drinking are associated with poorer self-perceived health status than regular, moderate consumption of other alcoholic beverages.

  14. Cigarette smoking, nicotine dependence and anxiety disorders: a systematic review of population-based, epidemiological studies

    Directory of Open Access Journals (Sweden)

    Moylan Steven

    2012-10-01

    Full Text Available Abstract Background Multiple studies have demonstrated that rates of smoking and nicotine dependence are increased in individuals with anxiety disorders. However, significant variability exists in the epidemiological literature exploring this relationship, including study design (cross-sectional versus prospective, the population assessed (random sample versus clinical population and diagnostic instrument utilized. Methods We undertook a systematic review of population-based observational studies that utilized recognized structured clinical diagnostic criteria (Diagnostic and Statistical Manual of Mental Disorders (DSM or International Classification of Diseases (ICD for anxiety disorder diagnosis to investigate the relationship between cigarette smoking, nicotine dependence and anxiety disorders. Results In total, 47 studies met the predefined inclusion criteria, with 12 studies providing prospective information and 5 studies providing quasiprospective information. The available evidence suggests that some baseline anxiety disorders are a risk factor for initiation of smoking and nicotine dependence, although the evidence is heterogeneous and many studies did not control for the effect of comorbid substance use disorders. The identified evidence however appeared to more consistently support cigarette smoking and nicotine dependence as being a risk factor for development of some anxiety disorders (for example, panic disorder, generalized anxiety disorder, although these findings were not replicated in all studies. A number of inconsistencies in the literature were identified. Conclusions Although many studies have demonstrated increased rates of smoking and nicotine dependence in individuals with anxiety disorders, there is a limited and heterogeneous literature that has prospectively examined this relationship in population studies using validated diagnostic criteria. The most consistent evidence supports smoking and nicotine dependence as

  15. Increased Risk of Acute Pancreatitis in Patients with Rheumatoid Arthritis: A Population-Based Cohort Study

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    Chang, Chi Ching; Chiou, Chi Sheng; Lin, Hsiu Li; Wang, Li Hsuan; Chang, Yu Sheng; Lin, Hsiu-Chen

    2015-01-01

    The study was conducted to determine whether patients with rheumatoid arthritis (RA) are at increased risk of acute pancreatitis compared with those without RA and to determine if the risk of acute pancreatitis varied by anti-RA drug use. We used the large population-based dataset from the National Health Insurance (NHI) program in Taiwan to conduct a retrospective cohort study. Patients newly diagnosed with RA between 2000 and 2011 were referred to as the RA group. The comparator non-RA group was matched with propensity score, using age and sex, in the same time period. We presented the incidence density by 100,000 person-years. The propensity score and all variables were analyzed in fully adjusted Cox proportional hazard regression. The cumulative incidence of acute pancreatitis was assessed by Kaplan-Meier analysis, with significance based on the log-rank test. From claims data of one million enrollees randomly sampled from the Taiwan NHI database, 29,755 adults with RA were identified and 119,020 non- RA persons were matched as a comparison group. The RA cohort had higher incidence density of acute pancreatitis (185.7 versus 119.0 per 100,000 person-years) than the non-RA cohort. The adjusted hazard ratio (HR) was 1.62 (95% CI [confidence interval] 1.43–1.83) for patients with RA to develop acute pancreatitis. Oral corticosteroid use decreased the risk of acute pancreatitis (adjusted HR 0.83, 95% CI 0.73–0.94) but without a dose-dependent effect. Current use of disease modifying anti-rheumatic drugs or tumor necrosis factor blockers did not decrease the risk of acute pancreatitis. In conclusion, patients with RA are at an elevated risk of acute pancreatitis. Use of oral corticosteroids may reduce the risk of acute pancreatitis. PMID:26262880

  16. School performance for children with cleft lip and palate: a population-based study.

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    Bell, J C; Raynes-Greenow, C; Turner, R; Bower, C; Dodson, A; Nicholls, W; Nassar, N

    2017-03-01

    Educational attainment is important in shaping young people's life prospects. To investigate whether being born with orofacial cleft (OFC) affects school performance, we compared school test results between children born with and without OFC. Using record-linked datasets, we conducted a population-based cohort study of children liveborn in Western Australia 1980-2010 with a diagnosis of OFC on the Register of Developmental Anomalies, and a random sample of 6603 children born without OFC. We compared odds ratios for meeting national minimum standards in five domains (reading, numeracy, writing, spelling, grammar and punctuation), and adjusted OR (aOR) for children with cleft lip only (CLO), cleft lip and palate (CL + P) and cleft palate only (CPO) for each domain. Results from two testing programs (WALNA and NAPLAN) were available for 3238 (89%) children expected to participate. Most met the national minimum standards. Compared with children without OFC, children with CPO were less likely to meet minimum standards for NAPLAN reading (aOR 0.57 [95%CI 0.34, 0.96]) grammar and punctuation (aOR 0.49 [95%CI 0.32, 0.76]), WALNA writing (aOR 0.66 [95%CI 0.47, 0.92]), and WALNA and NAPLAN numeracy (aOR 0.64 [95%CI 0.43, 0.95] and aOR 0.47 [95%CI 0.28, 0.82]), respectively. Children with CL + P had significantly lower odds for reaching the spelling standard in NAPLAN tests (aOR 0.52 [95%CI 0.29, 0.94]). Children with CLO had similar odds for reaching all minimum standards. Children born with OFC, particularly children with CPO, should be monitored to identify learning difficulties early, to enable intervention to maximize school attainment. © 2016 John Wiley & Sons Ltd.

  17. The Incidence of Japanese Encephalitis in Taiwan—A Population-Based Study

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    Hsu, Li-Ching; Chen, Yu-Ju; Hsu, Feng-Kuang; Huang, Jyh-Hsiung; Chang, Chi-Ming; Chou, Pesus; Lin, I-Feng; Chang, Feng-Yee

    2014-01-01

    Background A mass Japanese encephalitis (JE) vaccination program targeting children was launched in Taiwan in 1968, and the number of pediatric JE cases substantially decreased thereafter. The aim of this study was to elucidate the long-term trend of JE incidence, and to investigate the age-specific seroprevalence of JE-neutralizing antibodies. Methodology/Principal Findings A total of 2,948 laboratory-confirmed JE cases that occurred between 1966 and 2012 were analyzed using a mandatory notification system managed by the Centers for Disease Control, Taiwan. A total of 6,594 randomly-sampled serum specimens obtained in a nationwide population-based survey in 2002 were analyzed to estimate the seroprevalence of JE-neutralizing antibodies in the general population. The average annual JE incidence rate of the group aged 30 years and older was 0.167 cases per 100,000 people between 2001 and 2012, which was higher than the 0.052 cases per 100,000 people among those aged under 30 years. These seroepidemiological findings indicate that the cohort born between 1963 and 1975, who generally received two or three doses of the vaccine and were administered the last booster dose more than 20 years ago, exhibited the lowest positive rate of JE-neutralizing antibodies (54%). The highest and second highest antibody rates were observed, respectively, in the oldest unvaccinated cohort (86%) and in the youngest cohort born between 1981 and 1986, who received four doses 10–15 years ago (74%). Conclusion/Significance Over the past decade, the main age group of the confirmed JE cases in Taiwan shifted from young children to adults over 30 years of age. People who were born between 1963 and 1975 exhibited the lowest seroprevalence of JE-neutralizing antibodies. Thus, the key issue for JE control in Taiwan is to reduce adult JE cases through a cost-effective analysis of various immunization strategies. PMID:25058573

  18. Addictive behaviors related to opioid use for chronic pain: a population-based study.

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    Højsted, Jette; Ekholm, Ola; Kurita, Geana Paula; Juel, Knud; Sjøgren, Per

    2013-12-01

    The growing body of research showing increased opioid use in patients with chronic pain coupled with concerns regarding addiction encouraged the development of this population-based study. The goal of the study was to investigate the co-occurrence of indicators of addictive behaviors in patients with chronic non-cancer pain in long-term opioid treatment. The study combined data from the individual-based Danish Health Survey in 2010 and the official Danish health and socio-economic, individual-based registers. From a simple random sample of 25,000 adults (16 years or older) living in Denmark, 13,281 individuals were analyzed through multiple logistic regression analyses to assess the association between chronic pain (lasting ≥6 months), opioid use, health behavior, and body mass index. Six potential addictive behaviors were identified: daily smoking; high alcohol intake; illicit drug use in the past year; obesity; long-term use of benzodiazepines; and long-term use of benzodiazepine-related drugs. At least 2 of the 6 addictive behaviors were observed in 22.6% of the long-term opioid users with chronic pain compared with 11.5% of the non-opioid users with chronic pain and 8.9% of the individuals without chronic pain. Thus, a strong association was demonstrated between long-term opioid use and the clustering of addictive behaviors. An intricate relationship between chronic pain, opioid use, and addictive behaviors was observed in this study, which deserves both clinical attention and further research. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  19. Cigarette smoking, nicotine dependence and anxiety disorders: a systematic review of population-based, epidemiological studies

    Science.gov (United States)

    2012-01-01

    Background Multiple studies have demonstrated that rates of smoking and nicotine dependence are increased in individuals with anxiety disorders. However, significant variability exists in the epidemiological literature exploring this relationship, including study design (cross-sectional versus prospective), the population assessed (random sample versus clinical population) and diagnostic instrument utilized. Methods We undertook a systematic review of population-based observational studies that utilized recognized structured clinical diagnostic criteria (Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD)) for anxiety disorder diagnosis to investigate the relationship between cigarette smoking, nicotine dependence and anxiety disorders. Results In total, 47 studies met the predefined inclusion criteria, with 12 studies providing prospective information and 5 studies providing quasiprospective information. The available evidence suggests that some baseline anxiety disorders are a risk factor for initiation of smoking and nicotine dependence, although the evidence is heterogeneous and many studies did not control for the effect of comorbid substance use disorders. The identified evidence however appeared to more consistently support cigarette smoking and nicotine dependence as being a risk factor for development of some anxiety disorders (for example, panic disorder, generalized anxiety disorder), although these findings were not replicated in all studies. A number of inconsistencies in the literature were identified. Conclusions Although many studies have demonstrated increased rates of smoking and nicotine dependence in individuals with anxiety disorders, there is a limited and heterogeneous literature that has prospectively examined this relationship in population studies using validated diagnostic criteria. The most consistent evidence supports smoking and nicotine dependence as increasing the risk of

  20. Comorbilidad del trastorno de hiperactividad con déficit de atención (THDA en una muestra poblacional de niños y adolescentes escolares, Sabaneta, Colombia, 2001 Comorbidity of attention deficit hyperactivity disorder in a childhood and adolescent student population based sample, Colombia, 2001

    Directory of Open Access Journals (Sweden)

    Jaime Carrizosa Moog

    2007-04-01

    neurobehavioural disorder in childhood. METHODS: Descriptive, transversal study. Sample: random representative, poliaged, proportional according to group size for primary school students between 4 and 17 years of age. First stage ADHD screening checklist according to DSM-IV criteria. Second stage: structured neuropsychological interview, Conner´s checklist and intelligence quotient.The interview included DSM-IV diagnostic criteria for comorbidity. RESULTS: learning disorder was the most frequent comorbidity (15,1%, followed by oppositional defiant disorder (5%, generalized anxiety (2,7%, conduct disorders (2,7%, phobias (2,3, depression (1,8%, bipolar disorder (1,8%. Epilepsy and obsessive compulsive disorder represented each 0,9%. CONCLUSION: Learning Disorder is the most frequent comorbidity in children with THDA. The search for this comorbid condition represents a central hallmark in the successful evaluation and treatment of this condition.

  1. Nationwide and population-based prescription patterns in bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Vradi, Eleni; Andersen, Per Kragh

    2016-01-01

    OBJECTIVES: The aim of the present study was to describe prescription patterns and changes in these patterns over the last decade for patients diagnosed with bipolar disorder in mental healthcare, using population-based and nationwide data, and to relate the findings to recommendations from...... international guidelines. METHODS: A population-based, nationwide study was carried out. It included register-based longitudinal data on all patients with a first-ever contact with mental healthcare with a diagnosis of mania/bipolar disorder from the entire Danish population, and all prescription data...

  2. Wealth Inequality and Mental Disability Among the Chinese Population: A Population Based Study

    OpenAIRE

    Wang, Zhenjie; Du, Wei; Pang, Lihua; Zhang, Lei; Chen, Gong; Zheng, Xiaoying

    2015-01-01

    In the study described herein, we investigated and explored the association between wealth inequality and the risk of mental disability in the Chinese population. We used nationally represented, population-based data from the second China National Sample Survey on Disability, conducted in 2006. A total of 1,724,398 study subjects between the ages of 15 and 64, including 10,095 subjects with mental disability only, were used for the analysis. Wealth status was estimated by a wealth index tha...

  3. High Field In Vivo 13C Magnetic Resonance Spectroscopy of Brain by Random Radiofrequency Heteronuclear Decoupling and Data Sampling

    Science.gov (United States)

    Li, Ningzhi; Li, Shizhe; Shen, Jun

    2017-06-01

    In vivo 13C magnetic resonance spectroscopy (MRS) is a unique and effective tool for studying dynamic human brain metabolism and the cycling of neurotransmitters. One of the major technical challenges for in vivo 13C-MRS is the high radio frequency (RF) power necessary for heteronuclear decoupling. In the common practice of in vivo 13C-MRS, alkanyl carbons are detected in the spectra range of 10-65ppm. The amplitude of decoupling pulses has to be significantly greater than the large one-bond 1H-13C scalar coupling (1JCH=125-145 Hz). Two main proton decoupling methods have been developed: broadband stochastic decoupling and coherent composite or adiabatic pulse decoupling (e.g., WALTZ); the latter is widely used because of its efficiency and superb performance under inhomogeneous B1 field. Because the RF power required for proton decoupling increases quadratically with field strength, in vivo 13C-MRS using coherent decoupling is often limited to low magnetic fields (Drug Administration (FDA). Alternately, carboxylic/amide carbons are coupled to protons via weak long-range 1H-13C scalar couplings, which can be decoupled using low RF power broadband stochastic decoupling. Recently, the carboxylic/amide 13C-MRS technique using low power random RF heteronuclear decoupling was safely applied to human brain studies at 7T. Here, we review the two major decoupling methods and the carboxylic/amide 13C-MRS with low power decoupling strategy. Further decreases in RF power deposition by frequency-domain windowing and time-domain random under-sampling are also discussed. Low RF power decoupling opens the possibility of performing in vivo 13C experiments of human brain at very high magnetic fields (such as 11.7T), where signal-to-noise ratio as well as spatial and temporal spectral resolution are more favorable than lower fields.

  4. Rationale, design, methodology and sample characteristics for the Vietnam pre-conceptual micronutrient supplementation trial (PRECONCEPT: a randomized controlled study

    Directory of Open Access Journals (Sweden)

    Nguyen Phuong H

    2012-10-01

    Full Text Available Abstract Background Low birth weight and maternal anemia remain intractable problems in many developing countries. The adequacy of the current strategy of providing iron-folic acid (IFA supplements only during pregnancy has been questioned given many women enter pregnancy with poor iron stores, the substantial micronutrient demand by maternal and fetal tissues, and programmatic issues related to timing and coverage of prenatal care. Weekly IFA supplementation for women of reproductive age (WRA improves iron status and reduces the burden of anemia in the short term, but few studies have evaluated subsequent pregnancy and birth outcomes. The Preconcept trial aims to determine whether pre-pregnancy weekly IFA or multiple micronutrient (MM supplementation will improve birth outcomes and maternal and infant iron status compared to the current practice of prenatal IFA supplementation only. This paper provides an overview of study design, methodology and sample characteristics from baseline survey data and key lessons learned. Methods/design We have recruited 5011 WRA in a double-blind stratified randomized controlled trial in rural Vietnam and randomly assigned them to receive weekly supplements containing either: 1 2800 μg folic acid 2 60 mg iron and 2800 μg folic acid or 3 MM. Women who become pregnant receive daily IFA, and are being followed through pregnancy, delivery, and up to three months post-partum. Study outcomes include birth outcomes and maternal and infant iron status. Data are being collected on household characteristics, maternal diet and mental health, anthropometry, infant feeding practices, morbidity and compliance. Discussion The study is timely and responds to the WHO Global Expert Consultation which identified the need to evaluate the long term benefits of weekly IFA and MM supplementation in WRA. Findings will generate new information to help guide policy and programs designed to reduce the burden of anemia in women and

  5. Traumatic experiences and post-traumatic stress disorder among elderly Germans: results of a representative population-based survey.

    Science.gov (United States)

    Glaesmer, Heide; Gunzelmann, Thomas; Braehler, Elmar; Forstmeier, Simon; Maercker, Andreas

    2010-06-01

    Only a few population-based studies on the epidemiology of post-traumatic stress disorders (PTSDs) are available to date. Most of the existing studies are from the U.S.A. Against the background of World War II, the extent and long-term effects of war-related traumatic experiences in the German elderly population are of special interest. Nevertheless, population-based data on this topic are lacking to date. This study examines the occurrence of traumatic experiences and the prevalence rates of PTSD according to DSM-IV and of partial PTSD in a randomly selected sample of the German general population aged 60 years and over (N = 814) using self-rating instruments. PTSD is apparent in 3.4%; when partial post-traumatic stress syndromes are included, a total of 7.2% of the aged population are involved. The most common individual symptoms resulting from war-induced trauma are avoidance of thoughts and feelings, sleep disturbances, distressing dreams and intrusive thoughts. The most frequently mentioned traumatic experiences of the generation examined in this study were war-related trauma experienced as children or in early adulthood during World War II. As a person's age increases, so does the prevalence of war-related traumatic experiences. There are some gender differences in traumatic experiences, but not in post-traumatic symptoms. The results emphasize the importance of war-related traumatic experiences from World War II in the German elderly population and their impact on the prevalence of PTSD more than 60 years later.

  6. Prevalence and correlates of foot pain in a population-based study: the North West Adelaide health study

    Directory of Open Access Journals (Sweden)

    Hill Catherine L

    2008-07-01

    Full Text Available Abstract Background Few population-based studies have examined the prevalence of foot pain in the general community. The aims of this study were therefore to determine the prevalence, correlates and impact of foot pain in a population-based sample of people aged 18 years and over living in the northwest region of Adelaide, South Australia. Methods The North West Adelaide Health Study is a representative longitudinal cohort study of n = 4,060 people randomly selected and recruited by telephone interview. The second stage of data collection on this cohort was undertaken between mid 2004 and early 2006. In this phase, information regarding the prevalence of musculoskeletal conditions was included. Overall, n = 3,206 participants returned to the clinic during the second visit, and as part of the assessment were asked to report whether they had pain, aching or stiffness on most days in either of their feet. Data were also collected on body mass index (BMI; major medical conditions; other joint symptoms and health-related quality of life (the Medical Outcomes Study Short Form 36 [SF-36]. Results Overall, 17.4% (95% confidence interval 16.2 – 18.8 of participants indicated that they had foot pain, aching or stiffness in either of their feet. Females, those aged 50 years and over, classified as obese and who reported knee, hip and back pain were all significantly more likely to report foot pain. Respondents with foot pain scored lower on all domains of the SF-36 after adjustment for age, sex and BMI. Conclusion Foot pain affects nearly one in five of people in the community, is associated with increased age, female sex, obesity and pain in other body regions, and has a significant detrimental impact on health-related quality of life.

  7. Comparing attitudes about legal sanctions and teratogenic effects for cocaine, alcohol, tobacco and caffeine: A randomized, independent samples design

    Directory of Open Access Journals (Sweden)

    Alanis Kelly L

    2006-02-01

    Full Text Available Abstract Background Establishing more sensible measures to treat cocaine-addicted mothers and their children is essential for improving U.S. drug policy. Favorable post-natal environments have moderated potential deleterious prenatal effects. However, since cocaine is an illicit substance having long been demonized, we hypothesized that attitudes toward prenatal cocaine exposure would be more negative than for licit substances, alcohol, nicotine and caffeine. Further, media portrayals about long-term outcomes were hypothesized to influence viewers' attitudes, measured immediately post-viewing. Reducing popular crack baby stigmas could influence future policy decisions by legislators. In Study 1, 336 participants were randomly assigned to 1 of 4 conditions describing hypothetical legal sanction scenarios for pregnant women using cocaine, alcohol, nicotine or caffeine. Participants rated legal sanctions against pregnant women who used one of these substances and risk potential for developing children. In Study 2, 139 participants were randomly assigned to positive, neutral and negative media conditions. Immediately post-viewing, participants rated prenatal cocaine-exposed or non-exposed teens for their academic performance and risk for problems at age18. Results Participants in Study 1 imposed significantly greater legal sanctions for cocaine, perceiving prenatal cocaine exposure as more harmful than alcohol, nicotine or caffeine. A one-way ANOVA for independent samples showed significant differences, beyond .0001. Post-hoc Sheffe test illustrated that cocaine was rated differently from other substances. In Study 2, a one-way ANOVA for independent samples was performed on difference scores for the positive, neutral or negative media conditions about prenatal cocaine exposure. Participants in the neutral and negative media conditions estimated significantly lower grade point averages and more problems for the teen with prenatal cocaine exposure

  8. Comparing attitudes about legal sanctions and teratogenic effects for cocaine, alcohol, tobacco and caffeine: A randomized, independent samples design

    Science.gov (United States)

    Ginsburg, Harvey J; Raffeld, Paul; Alanis, Kelly L; Boyce, Angela S

    2006-01-01

    Background Establishing more sensible measures to treat cocaine-addicted mothers and their children is essential for improving U.S. drug policy. Favorable post-natal environments have moderated potential deleterious prenatal effects. However, since cocaine is an illicit substance having long been demonized, we hypothesized that attitudes toward prenatal cocaine exposure would be more negative than for licit substances, alcohol, nicotine and caffeine. Further, media portrayals about long-term outcomes were hypothesized to influence viewers' attitudes, measured immediately post-viewing. Reducing popular crack baby stigmas could influence future policy decisions by legislators. In Study 1, 336 participants were randomly assigned to 1 of 4 conditions describing hypothetical legal sanction scenarios for pregnant women using cocaine, alcohol, nicotine or caffeine. Participants rated legal sanctions against pregnant women who used one of these substances and risk potential for developing children. In Study 2, 139 participants were randomly assigned to positive, neutral and negative media conditions. Immediately post-viewing, participants rated prenatal cocaine-exposed or non-exposed teens for their academic performance and risk for problems at age18. Results Participants in Study 1 imposed significantly greater legal sanctions for cocaine, perceiving prenatal cocaine exposure as more harmful than alcohol, nicotine or caffeine. A one-way ANOVA for independent samples showed significant differences, beyond .0001. Post-hoc Sheffe test illustrated that cocaine was rated differently from other substances. In Study 2, a one-way ANOVA for independent samples was performed on difference scores for the positive, neutral or negative media conditions about prenatal cocaine exposure. Participants in the neutral and negative media conditions estimated significantly lower grade point averages and more problems for the teen with prenatal cocaine exposure than for the non-exposed teen

  9. QTL mapping for combining ability in different population-based ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 92; Issue 3. QTL mapping for combining ability in different population-based NCII designs: a simulation study. Lanzhi Li Congwei Sun ... The NCII design (North Carolina mating design II) has been widely applied in studies of combining ability and heterosis. The objective of our ...

  10. Population Based Survey of Chronic Non-Communicable Diseases ...

    African Journals Online (AJOL)

    Population Based Survey of Chronic Non-Communicable Diseases at Gilgel Gibe Field Research Center, Southwest Ethiopia. ... Blood pressure was taken three times from each individual and blood sugar and lipid levels were determined after an overnight fasting. Data were analyzed using SPSS for Windows version 16.0 ...

  11. Methods for a Retrospective Population-based and Clinic-based Subfertility Cohort Study: the Fertility Experiences Study.

    Science.gov (United States)

    Stanford, Joseph B; Sanders, Jessica N; Simonsen, Sara E; Hammoud, Ahmad; Gibson, Mark; Smith, Ken R

    2016-07-01

    Most cohort-based research for subfertility has been conducted in clinic-based cohorts, which may differ from population-based cohorts. We retrospectively recruited parallel cohorts of subfertile women: one by sampling two specialty fertility clinics in Utah, and one by population-based sampling based on marriage and birth records. The index date (of first clinic visit or subfertility status) was between 2000 and 2009, and we linked the women recruited to subsequent birth certificate records through December 2010. We enrolled 459 women through clinic-based sampling and 501 women through population-based sampling. Clinic-based women were older, had higher annual household income and more likely to have had a most intensive treatment of intrauterine insemination (31%) or in vitro fertilisation (46%) than women from population recruitment (19% and 14% respectively). Conversely, they were less likely to have received no medical treatment (9%) compared to women from population recruitment (41%). For both types of sampling, prior to eligibility screening, non-responders were less likely to link to a live birth than responders: 51% vs. 58% for clinic-based, and 69% vs. 76% for the population-based with an index date in 2004. Population-based sampling for subfertility cohort research identifies women who were more likely to have had less intensive treatment or no treatment. However, in both clinic-based and population-based sampling, women who have had a live birth are more likely to respond to retrospective recruitment. © 2016 John Wiley & Sons Ltd.

  12. Neighborhood deprivation is strongly associated with participation in a population-based health check

    DEFF Research Database (Denmark)

    Bender, Anne Mette; Kawachi, Ichiro; Jørgensen, Torben

    2015-01-01

    BACKGROUND: We sought to examine whether neighborhood deprivation is associated with participation in a large population-based health check. Such analyses will help answer the question whether health checks, which are designed to meet the needs of residents in deprived neighborhoods, may increase...... screening for ischemic heart disease and lifestyle counseling. The study population was randomly drawn from a population of 179,097 persons living in 73 neighborhoods in Denmark. Data on neighborhood deprivation (percentage with basic education, with low income and not in work) and individual socioeconomic...

  13. Psychological distress among Bam earthquake survivors in Iran: a population-based study

    Directory of Open Access Journals (Sweden)

    Garmaroudi Gholamreza

    2005-01-01

    Full Text Available Abstract Background An earthquake measuring 6.3 on the Richter scale struck the city of Bam in Iran on the 26th of December 2003 at 5.26 A.M. It was devastating, and left over 40,000 dead and around 30,000 injured. The profound tragedy of thousands killed has caused emotional and psychological trauma for tens of thousands of people who have survived. A study was carried out to assess psychological distress among Bam earthquake survivors and factors associated with severe mental health in those who survived the tragedy. Methods This was a population-based study measuring psychological distress among the survivors of Bam earthquake in Iran. Using a multi-stage stratified sampling method a random sample of individuals aged 15 years and over living in Bam were interviewed. Psychological distress was measured using the 12-item General Health Questionnaire (GHQ-12. Results In all 916 survivors were interviewed. The mean age of the respondents was 32.9 years (SD = 12.4, mostly were males (53%, married (66% and had secondary school education (50%. Forty-one percent reported they lost 3 to 5 members of their family in the earthquake. In addition the findings showed that 58% of the respondents suffered from severe mental health as measured by the GHQ-12 and this was three times higher than reported psychological distress among the general population. There were significant differences between sub-groups of the study sample with regard to their psychological distress. The results of the logistic regression analysis also indicated that female gender; lower education, unemployment, and loss of family members were associated with severe psychological distress among earthquake victims. Conclusion The study findings indicated that the amount of psychological distress among earthquake survivors was high and there is an urgent need to deliver mental health care to disaster victims in local medical settings and to reduce negative health impacts of the earthquake

  14. Burden of road traffic injuries in Nepal: results of a countrywide population-based survey.

    Science.gov (United States)

    Nepal, Sarthak; Gupta, Shailvi; Wong, Evan G; Gurung, Susant; Swaroop, Mamta; Kushner, Adam L; Nwomeh, Benedict C

    2015-04-27

    Road traffic injury has emerged as a leading cause of mortality, contributing to 2·1% of deaths globally and is predicted to be the third highest contributor to the global burden of mortality by 2020. This major public health problem disproportionately affects low-income and middle-income countries, where such incidents are too often underreported. Our study aims to explore the epidemiology of road traffic injurys in Nepal at a population level via a countrywide study. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) tool, a cluster randomised, cross-sectional nationwide survey, was conducted in Nepal between May 25, and June 12, 2014. Two-stage cluster sampling was performed: 15 of 75 districts were chosen randomly proportional to population; within each district, after stratification for urban and rural, and three clusters were randomly chosen. Questions were structured anatomically and designed around a representative spectrum of surgical conditions. Road traffic injury-related results were reported. 1350 households and 2695 individuals were surveyed with a response rate of 97%. 75 road traffic injuries were reported in 72 individuals (2·67% [95% CI 2·10-3·35] of the study population), with a mean age of 33·2 years (SD 1·85). The most commonly affected age group was 30-44 years, with females showing significantly lower odds of sustaining a road traffic injury than men (crude odds ratio 0·29 [95% CI 0·16-0·52]). Road traffic injuries composed 19·8% of the injuries reported. Motorcycle crashes were the most common road traffic injuries (48·0%), followed by car, truck, or bus crashes (26·7%), and pedestrian or bicycle crashes (25·3%). The extremity was the most common anatomic site injured (74·7%). Of the 80 deaths reported in the previous year, 7·5% (n=6) were due to road traffic injuries. This study provides the epidemiology of road traffic injuries at a population-based level in the first countrywide surgical needs assessment in Nepal

  15. Population based estimates of non-fatal injuries in the capital of Iran

    Directory of Open Access Journals (Sweden)

    Mafi Mostafa

    2011-07-01

    Full Text Available Abstract Background Fatal injuries are at the top of the injury pyramid; however, non-fatal injuries are quite common and impose huge medical expenses on the population. Relying on hospital data will underestimate the incidence of non-fatal injuries. The aim of this study was to estimate the annual incidence and out of pocket medical expenses of all injuries in urban population of Tehran (the capital city of Iran. Methods Using the cluster random sampling approach, a household survey of residents of greater Tehran was performed on April 2008. At randomly selected residential locations, interviewers asked one adult person to report all injuries which have occurred during the past year for all household members, as well as the type of injury, place of occurrence, the activity, cause of accidents resulting in injuries, the amount of out of pocket medical expenses for injury, and whether they referred to hospital. Results This study included 2,450 households residing in Tehran during 2007-8. The annual incidence of all injuries was 188.7 (180.7-196.9, significant injuries needing any medical care was 68.8 (63.7-74.2, fractures was 19.3 (16.6 - 22.4, and injuries resulted in hospitalization was 16.7 (14.2 - 19.6 per 1000 population. The annual incidence of fatal injuries was 33 (7-96 per 100,000 Population. In children aged 15 or less, the annual incidence of all injuries was 137.2 (120.0 - 155.9, significant injuries needing any medical care was 64.2 (52.2 - 78.0, fractures was 21.8 (15.0 - 30.7, and injuries resulted in hospitalization was 6.8 (3.3 - 12.5 per 1000 population. The mean out of pocket medical expense for injuries was 19.9 USD. Conclusion This population based study showed that the real incidence of non-fatal injuries in the capital of Iran is more than the formal hospital-based estimates. These injuries impose non trivial medical and indirect cost on the community. The out of pocket medical expense of non-fatal injuries to Tehran

  16. Assessing causality in associations between cannabis use and schizophrenia risk: a two-sample Mendelian randomization study.

    Science.gov (United States)

    Gage, S H; Jones, H J; Burgess, S; Bowden, J; Davey Smith, G; Zammit, S; Munafò, M R

    2017-04-01

    Observational associations between cannabis and schizophrenia are well documented, but ascertaining causation is more challenging. We used Mendelian randomization (MR), utilizing publicly available data as a method for ascertaining causation from observational data. We performed bi-directional two-sample MR using summary-level genome-wide data from the International Cannabis Consortium (ICC) and the Psychiatric Genomics Consortium (PGC2). Single nucleotide polymorphisms (SNPs) associated with cannabis initiation (p schizophrenia (p cannabis initiation on risk of schizophrenia [odds ratio (OR) 1.04 per doubling odds of cannabis initiation, 95% confidence interval (CI) 1.01-1.07, p = 0.019]. There was strong evidence consistent with a causal effect of schizophrenia risk on likelihood of cannabis initiation (OR 1.10 per doubling of the odds of schizophrenia, 95% CI 1.05-1.14, p = 2.64 × 10-5). Findings were as predicted for the negative control (height: OR 1.00, 95% CI 0.99-1.01, p = 0.90) but weaker than predicted for the positive control (years in education: OR 0.99, 95% CI 0.97-1.00, p = 0.066) analyses. Our results provide some that cannabis initiation increases the risk of schizophrenia, although the size of the causal estimate is small. We find stronger evidence that schizophrenia risk predicts cannabis initiation, possibly as genetic instruments for schizophrenia are stronger than for cannabis initiation.

  17. Multiple-image authentication with a cascaded multilevel architecture based on amplitude field random sampling and phase information multiplexing.

    Science.gov (United States)

    Fan, Desheng; Meng, Xiangfeng; Wang, Yurong; Yang, Xiulun; Pan, Xuemei; Peng, Xiang; He, Wenqi; Dong, Guoyan; Chen, Hongyi

    2015-04-10

    A multiple-image authentication method with a cascaded multilevel architecture in the Fresnel domain is proposed, in which a synthetic encoded complex amplitude is first fabricated, and its real amplitude component is generated by iterative amplitude encoding, random sampling, and space multiplexing for the low-level certification images, while the phase component of the synthetic encoded complex amplitude is constructed by iterative phase information encoding and multiplexing for the high-level certification images. Then the synthetic encoded complex amplitude is iteratively encoded into two phase-type ciphertexts located in two different transform planes. During high-level authentication, when the two phase-type ciphertexts and the high-level decryption key are presented to the system and then the Fresnel transform is carried out, a meaningful image with good quality and a high correlation coefficient with the original certification image can be recovered in the output plane. Similar to the procedure of high-level authentication, in the case of low-level authentication with the aid of a low-level decryption key, no significant or meaningful information is retrieved, but it can result in a remarkable peak output in the nonlinear correlation coefficient of the output image and the corresponding original certification image. Therefore, the method realizes different levels of accessibility to the original certification image for different authority levels with the same cascaded multilevel architecture.

  18. Mental health impact of the 2010 Haiti earthquake on the Miami Haitian population: A random-sample survey.

    Science.gov (United States)

    Messiah, Antoine; Acuna, Juan M; Castro, Grettel; de la Vega, Pura Rodríguez; Vaiva, Guillaume; Shultz, James; Neria, Yuval; De La Rosa, Mario

    2014-07-01

    This study examined the mental health consequences of the January 2010 Haiti earthquake on Haitians living in Miami-Dade County, Florida, 2-3 years following the event. A random-sample household survey was conducted from October 2011 through December 2012 in Miami-Dade County, Florida. Haitian participants (N = 421) were assessed for their earthquake exposure and its impact on family, friends, and household finances; and for symptoms of posttraumatic stress disorder (PTSD), anxiety, and major depression; using standardized screening measures and thresholds. Exposure was considered as "direct" if the interviewee was in Haiti during the earthquake. Exposure was classified as "indirect" if the interviewee was not in Haiti during the earthquake but (1) family members or close friends were victims of the earthquake, and/or (2) family members were hosted in the respondent's household, and/or (3) assets or jobs were lost because of the earthquake. Interviewees who did not qualify for either direct or indirect exposure were designated as "lower" exposure. Eight percent of respondents qualified for direct exposure, and 63% qualified for indirect exposure. Among those with direct exposure, 19% exceeded threshold for PTSD, 36% for anxiety, and 45% for depression. Corresponding percentages were 9%, 22% and 24% for respondents with indirect exposure, and 6%, 14%, and 10% for those with lower exposure. A majority of Miami Haitians were directly or indirectly exposed to the earthquake. Mental health distress among them remains considerable two to three years post-earthquake.

  19. Mental Health Impact of Hosting Disaster Refugees: Analyses from a Random Sample Survey Among Haitians Living in Miami.

    Science.gov (United States)

    Messiah, Antoine; Lacoste, Jérôme; Gokalsing, Erick; Shultz, James M; Rodríguez de la Vega, Pura; Castro, Grettel; Acuna, Juan M

    2016-08-01

    Studies on the mental health of families hosting disaster refugees are lacking. This study compares participants in households that hosted 2010 Haitian earthquake disaster refugees with their nonhost counterparts. A random sample survey was conducted from October 2011 through December 2012 in Miami-Dade County, Florida. Haitian participants were assessed regarding their 2010 earthquake exposure and impact on family and friends and whether they hosted earthquake refugees. Using standardized scores and thresholds, they were evaluated for symptoms of three common mental disorders (CMDs): posttraumatic stress disorder, generalized anxiety disorder, and major depressive disorder (MDD). Participants who hosted refugees (n = 51) had significantly higher percentages of scores beyond thresholds for MDD than those who did not host refugees (n = 365) and for at least one CMD, after adjusting for participants' earthquake exposures and effects on family and friends. Hosting refugees from a natural disaster appears to elevate the risk for MDD and possibly other CMDs, independent of risks posed by exposure to the disaster itself. Families hosting refugees deserve special attention.

  20. Randomization modeling to ascertain clustering patterns of human papillomavirus types detected in cervicovaginal samples in the United States.

    Directory of Open Access Journals (Sweden)

    Troy David Querec

    Full Text Available Detection of multiple human papillomavirus (HPV types in the genital tract is common. Associations among HPV types may impact HPV vaccination modeling and type replacement. The objectives were to determine the distribution of concurrent HPV type infections in cervicovaginal samples and examine type-specific associations. We analyzed HPV genotyping results from 32,245 cervicovaginal specimens collected from women aged 11 to 83 years in the United States from 2001 through 2011. Statistical power was enhanced by combining 6 separate studies. Expected concurrent infection frequencies from a series of permutation models, each with increasing fidelity to the real data, were compared with the observed data. Statistics were computed based on the distributional properties of the randomized data. Concurrent detection occurred more than expected with 0 or ≥3 HPV types and less than expected with 1 and 2 types. Some women bear a disproportionate burden of the HPV type prevalence. Type associations were observed that exceeded multiple hypothesis corrected significance. Multiple HPV types were detected more frequently than expected by chance and associations among particular HPV types were detected. However vaccine-targeted types were not specifically affected, supporting the expectation that current bivalent/quadrivalent HPV vaccination will not result in type replacement with other high-risk types.

  1. Cyberbullying among Finnish adolescents--a population-based study.

    Science.gov (United States)

    Lindfors, Pirjo L; Kaltiala-Heino, Riittakerttu; Rimpelä, Arja H

    2012-11-23

    Cyberbullying, threatening or harassing another via the internet or mobile phones, does not cause physically harm and thus the consequences are less visible. Little research has been performed on the occurrence of cyberbullying among adolescents or the perception of its seriousness. Only a few population-based studies have been published, none of which included research on the witnessing of cyberbullying. Here, we examined exposure to cyberbullying during the last year, and its frequency and perceived seriousness among 12 to 18-year-old adolescents in Finland. We studied four dimensions of cyberbullying: being a victim, bully, or both victim and bully of cyberbullying, and witnessing the cyberbullying of friends. Self-administered questionnaires, including four questions on cyberbullying, were mailed to a representative sample of 12-, 14-, 16-, and 18-year-old Finns in 2009 (the Adolescent Health and Lifestyle Survey). The respondents could answer via the internet or paper questionnaire. The number of respondents was 5516 and the response rate was 56%. Girls more often than boys reported experiencing at least one dimension of cyberbullying during the last year. The proportion was highest among 14-year-olds and lowest among 18-year-olds of both sexes. Among girls, the most commonly encountered dimension was witnessing the cyberbullying of friends (16%); and being a victim was slightly more common than being a bully (11% vs. 9%). Among boys, an equal proportion, approximately 10%, had been a victim, a bully, or had witnessed cyberbullying. The proportion of bully-victims was 4%. Serious and disruptive cyberbullying was experienced by 2% of respondents and weekly cyberbullying by 1%; only 0.5% of respondents had been bullied weekly and considered bullying serious and disruptive. Adolescents are commonly exposed to cyberbullying, but it is rarely frequent or considered serious or disruptive. Cyberbullying exposure differed between sexes, such that girls more often than

  2. Cyberbullying among Finnish adolescents – a population-based study

    Science.gov (United States)

    2012-01-01

    Background Cyberbullying, threatening or harassing another via the internet or mobile phones, does not cause physically harm and thus the consequences are less visible. Little research has been performed on the occurrence of cyberbullying among adolescents or the perception of its seriousness. Only a few population-based studies have been published, none of which included research on the witnessing of cyberbullying. Here, we examined exposure to cyberbullying during the last year, and its frequency and perceived seriousness among 12 to 18-year-old adolescents in Finland. We studied four dimensions of cyberbullying: being a victim, bully, or both victim and bully of cyberbullying, and witnessing the cyberbullying of friends. Methods Self-administered questionnaires, including four questions on cyberbullying, were mailed to a representative sample of 12-, 14-, 16-, and 18-year-old Finns in 2009 (the Adolescent Health and Lifestyle Survey). The respondents could answer via the internet or paper questionnaire. Results The number of respondents was 5516 and the response rate was 56%. Girls more often than boys reported experiencing at least one dimension of cyberbullying during the last year. The proportion was highest among 14-year-olds and lowest among 18-year-olds of both sexes. Among girls, the most commonly encountered dimension was witnessing the cyberbullying of friends (16%); and being a victim was slightly more common than being a bully (11% vs. 9%). Among boys, an equal proportion, approximately 10%, had been a victim, a bully, or had witnessed cyberbullying. The proportion of bully-victims was 4%. Serious and disruptive cyberbullying was experienced by 2% of respondents and weekly cyberbullying by 1%; only 0.5% of respondents had been bullied weekly and considered bullying serious and disruptive. Conclusions Adolescents are commonly exposed to cyberbullying, but it is rarely frequent or considered serious or disruptive. Cyberbullying exposure differed between

  3. Cyberbullying among Finnish adolescents – a population-based study

    Directory of Open Access Journals (Sweden)

    Lindfors Pirjo L

    2012-11-01

    Full Text Available Abstract Background Cyberbullying, threatening or harassing another via the internet or mobile phones, does not cause physically harm and thus the consequences are less visible. Little research has been performed on the occurrence of cyberbullying among adolescents or the perception of its seriousness. Only a few population-based studies have been published, none of which included research on the witnessing of cyberbullying. Here, we examined exposure to cyberbullying during the last year, and its frequency and perceived seriousness among 12 to 18-year-old adolescents in Finland. We studied four dimensions of cyberbullying: being a victim, bully, or both victim and bully of cyberbullying, and witnessing the cyberbullying of friends. Methods Self-administered questionnaires, including four questions on cyberbullying, were mailed to a representative sample of 12-, 14-, 16-, and 18-year-old Finns in 2009 (the Adolescent Health and Lifestyle Survey. The respondents could answer via the internet or paper questionnaire. Results The number of respondents was 5516 and the response rate was 56%. Girls more often than boys reported experiencing at least one dimension of cyberbullying during the last year. The proportion was highest among 14-year-olds and lowest among 18-year-olds of both sexes. Among girls, the most commonly encountered dimension was witnessing the cyberbullying of friends (16%; and being a victim was slightly more common than being a bully (11% vs. 9%. Among boys, an equal proportion, approximately 10%, had been a victim, a bully, or had witnessed cyberbullying. The proportion of bully-victims was 4%. Serious and disruptive cyberbullying was experienced by 2% of respondents and weekly cyberbullying by 1%; only 0.5% of respondents had been bullied weekly and considered bullying serious and disruptive. Conclusions Adolescents are commonly exposed to cyberbullying, but it is rarely frequent or considered serious or disruptive. Cyberbullying

  4. Universal-Based Prevention of Syndromal and Subsyndromal Social Anxiety: A Randomized Controlled Study

    Science.gov (United States)

    Aune, Tore; Stiles, Tore C.

    2009-01-01

    This article reports results from a universal preventive program aimed at (a) reducing social anxiety and (b) preventing the development of syndromal social anxiety among a population-based sample of older children and young adolescents during a 1-year period. Pupils (N = 1,748) from 2 counties were cluster randomized to either an intervention or…

  5. [Acupuncture and moxibustion for peripheral facial palsy at different stages: multi-central large-sample randomized controlled trial].

    Science.gov (United States)

    Li, Ying; Li, Yan; Liu, Li-an; Zhao, Ling; Hu, Ka-ming; Wu, Xi; Chen, Xiao-qin; Li, Gui-ping; Mang, Ling-ling; Qi, Qi-hua

    2011-04-01

    To explore the best intervention time of acupuncture and moxibustion for peripheral facial palsy (Bell's palsy) and the clinical advantage program of selective treatment with acupuncture and moxibustion. Multi-central large-sample randomized controlled trial was carried out. Nine hundreds cases of Bell's palsy were randomized into 5 treatment groups, named selective filiform needle group (group A), selective acupuncture + moxibustion group (group B), selective acupuncture + electroacupuncture (group C), selective acupuncture + line-up needling on muscle region of meridian group (group D) and non-selective filiform needle group (group E). Four sessions of treatment were required in each group. Separately, during the enrollment, after 4 sessions of treatment, in 1 month and 3 months of follow-up after treatment, House-Brackmann Scale, Facial Disability Index Scale and Degree of Facial Nerve Paralysis (NFNP) were adopted for efficacy assessment. And the efficacy systematic analysis was provided in view of the intervention time and nerve localization of disease separately. The curative rates of intervention in acute stage and resting stage were 50.1% (223/445) and 52.1% (162/311), which were superior to recovery stage (25.9%, 35/135) separately. There were no statistical significant differences in efficacy in comparison among 5 treatment programs at the same stage (all P > 0.05). The efficacy of intervention of group A and group E in acute stage was superior to that in recovery stage (both P < 0.01). The difference was significant statistically between the efficacy on the localization above chorda tympani nerve and that on the localization below the nerve in group D (P < 0.01). The efficacy on the localization below chorda tympani nerve was superior to the localization above the nerve. The best intervention time for the treatment of Bell's palsy is in acute stage and resting stage, meaning 1 to 3 weeks after occurrence. All of the 5 treatment programs are advantageous

  6. Tobacco smoking surveillance: is quota sampling an efficient tool for monitoring national trends? A comparison with a random cross-sectional survey.

    Directory of Open Access Journals (Sweden)

    Romain Guignard

    Full Text Available OBJECTIVES: It is crucial for policy makers to monitor the evolution of tobacco smoking prevalence. In France, this monitoring is based on a series of cross-sectional general population surveys, the Health Barometers, conducted every five years and based on random samples. A methodological study has been carried out to assess the reliability of a monitoring system based on regular quota sampling surveys for smoking prevalence. DESIGN / OUTCOME MEASURES: In 2010, current and daily tobacco smoking prevalences obtained in a quota survey on 8,018 people were compared with those of the 2010 Health Barometer carried out on 27,653 people. Prevalences were assessed separately according to the telephone equipment of the interviewee (landline phone owner vs "mobile-only", and logistic regressions were conducted in the pooled database to assess the impact of the telephone equipment and of the survey mode on the prevalences found. Finally, logistic regressions adjusted for sociodemographic characteristics were conducted in the random sample in order to determine the impact of the needed number of calls to interwiew "hard-to-reach" people on the prevalence found. RESULTS: Current and daily prevalences were higher in the random sample (respectively 33.9% and 27.5% in 15-75 years-old than in the quota sample (respectively 30.2% and 25.3%. In both surveys, current and daily prevalences were lower among landline phone owners (respectively 31.8% and 25.5% in the random sample and 28.9% and 24.0% in the quota survey. The required number of calls was slightly related to the smoking status after adjustment for sociodemographic characteristics. CONCLUSION: Random sampling appears to be more effective than quota sampling, mainly by making it possible to interview hard-to-reach populations.

  7. Recurrence of hyperemesis gravidarum across generations: population based cohort study

    OpenAIRE

    Vikanes, ?se; Skj?rven, Rolv; Grjibovski, Andrej M; Gunnes, Nina; Vangen, Siri; Magnus, Per

    2010-01-01

    Objective To estimate the risk of hyperemesis gravidarum (hyperemesis) according to whether the daughters and sons under study were born after pregnancies complicated by hyperemesis. Design Population based cohort study. Setting Registry data from Norway. Participants Linked generational data from the medical birth registry of Norway (1967-2006): 544?087 units of mother and childbearing daughter and 399?777 units of mother and child producing son. Main outcome measure Hyperemesis in daughters...

  8. Cyberbullying among Finnish adolescents ? a population-based study

    OpenAIRE

    Lindfors Pirjo L; Kaltiala-Heino Riittakerttu; Rimpelä Arja H

    2012-01-01

    Abstract Background Cyberbullying, threatening or harassing another via the internet or mobile phones, does not cause physically harm and thus the consequences are less visible. Little research has been performed on the occurrence of cyberbullying among adolescents or the perception of its seriousness. Only a few population-based studies have been published, none of which included research on the witnessing of cyberbullying. Here, we examined exposure to cyberbullying during the last year, an...

  9. A population-based prospective study of optic neuritis

    DEFF Research Database (Denmark)

    Soelberg, K; Jarius, S; Skejoe, Hanne Pernille Bro

    2017-01-01

    BACKGROUND: Optic neuritis (ON) is often associated with multiple sclerosis (MS). Early diagnosis is critical to optimal patient management. OBJECTIVE: To estimate the incidence of acute ON and the rates of conversion to MS and antibody-mediated ON. METHOD: Population-based prospective study......: The prospective incidence of ON was estimated. MRI enabled a diagnosis of MS in a subgroup of patients. Antibody-mediated ON with specificity for MOG was detected in 4% of cases....

  10. Women's intentions to breastfeed: a population-based cohort study.

    Science.gov (United States)

    Lutsiv, O; Pullenayegum, E; Foster, G; Vera, C; Giglia, L; Chapman, B; Fusch, C; McDonald, S D

    2013-11-01

    Given that intention to breastfeed is a strong predictor of breastfeeding initiation and duration, the objectives of this study were to estimate the population-based prevalence and the factors associated with the intention to breastfeed. Retrospective population-based cohort study. All hospitals in Ontario, Canada (1 April 2009-31 March 2010). Women who gave birth to live, term, singletons/twins. Patient, healthcare provider, and hospital factors that may be associated with intention to breastfeed were analysed using univariable and multivariable regression. Population-based prevalence of intention to breastfeed and its associated factors. The study included 92,364 women, of whom 78,806 (85.3%) intended to breastfeed. The odds of intending to breastfeed were higher amongst older women with no health problems and women who were cared for exclusively by midwives (adjusted OR 3.64, 95% CI 3.13-4.23). Being pregnant with twins (adjusted OR 0.73, 95% CI 0.57-0.94), not attending antenatal classes (adjusted OR 0.58, 95% CI 0.54-0.62), having previous term or preterm births (adjusted OR 0.79, 95% CI 0.78-0.81, and adjusted OR 0.87, 95% CI 0.82-0.93, respectively), and delivering in a level-1 hospital (adjusted OR 0.85, 95% CI 0.77-0.93) were associated with a lower intention to breastfeed. In this population-based study ~85% of women intended to breastfeed their babies. Key factors that are associated with the intention to breastfeed were identified, which can now be targeted for intervention programmes aimed at increasing the prevalence of breastfeeding and improving overall child and maternal health. © 2013 RCOG.

  11. Differentiating intraprofessional attitudes toward paradigms in health care delivery among chiropractic factions: results from a randomly sampled survey

    Science.gov (United States)

    2014-01-01

    Background As health care has increased in complexity and health care teams have been offered as a solution, so too is there an increased need for stronger interprofessional collaboration. However the intraprofessional factions that exist within every profession challenge interprofessional communication through contrary paradigms. As a contender in the conservative spinal health care market, factions within chiropractic that result in unorthodox practice behaviours may compromise interprofessional relations and that profession’s progress toward institutionalization. The purpose of this investigation was to quantify the professional stratification among Canadian chiropractic practitioners and evaluate the practice perceptions of those factions. Methods A stratified random sample of 740 Canadian chiropractors was surveyed to determine faction membership and how professional stratification could be related to views that could be considered unorthodox to current evidence-based care and guidelines. Stratification in practice behaviours is a stated concern of mainstream medicine when considering interprofessional referrals. Results Of 740 deliverable questionnaires, 503 were returned for a response rate of 68%. Less than 20% of chiropractors (18.8%) were aligned with a predefined unorthodox perspective of the conditions they treat. Prediction models suggest that unorthodox perceptions of health practice related to treatment choices, x-ray use and vaccinations were strongly associated with unorthodox group membership (X2 =13.4, p = 0.0002). Conclusion Chiropractors holding unorthodox views may be identified based on response to specific beliefs that appear to align with unorthodox health practices. Despite continued concerns by mainstream medicine, only a minority of the profession has retained a perspective in contrast to current scientific paradigms. Understanding the profession’s factions is important to the anticipation of care delivery when considering

  12. Intent to breastfeed: a population-based perspective.

    Science.gov (United States)

    Chertok, Ilana R Azulay; Luo, Juhua; Culp, Stacey; Mullett, Martha

    2011-06-01

    Prenatal maternal intent to breastfeed can indicate postnatal breastfeeding practices and may serve to indicate potential barriers to breastfeeding. Breastfeeding rates in West Virginia, a primarily rural state, are among the lowest in the United States, and minimal research has been published to date on population-based prenatal intent to breastfeed among rural women. Secondary data analysis of population-based data was conducted using two state-linked datasets. State data included all live singleton births from at least 20 weeks of gestation in West Virginia from 2004 to 2006, for a total of 52,899 births. Results from the logistic regression model for the population-based study indicate that variables predicting intent to breastfeed among pregnant women in West Virginia include insurance status, maternal education, maternal age, parity, marital status, timing of prenatal care initiation, and prenatal smoking status. Prenatal identification of characteristics associated with lack of intent to breastfeed can serve to inform healthcare providers of women who are at risk for not breastfeeding for directed breastfeeding promotion and intervention, complementing education of healthy lifestyle choices such as breastfeeding promotion with smoking cessation.

  13. Population-based screening for colorectal cancer using an immunochemical faecal occult blood test: a comparison of two invitation strategies.

    Science.gov (United States)

    Van Roosbroeck, Sofie; Hoeck, Sarah; Van Hal, Guido

    2012-10-01

    To date, there is no screening programme for colorectal cancer (CRC) in Flanders, Belgium. However, The European Code Against Cancer (2003) recommends a population-based approach for CRC screening. This study aimed to obtain information about potential participation rates for a population-based screening programme for CRC in Flanders, and to compare two invitation strategies. In 2009, a trial programme for CRC screening was set up in three Flemish areas for all average-risk people aged 50-74 years, using an immunochemical faecal occult blood test (iFOBT) with a cut-off value set at 75 ng/ml of haemoglobin. The faecal sampling set was sent at random by post (mail group) or provided by the general practitioner (GP group). In total, 19,542 people were invited to participate. Of these, 8229 provided a faecal sample, resulting in an overall participation rate of 42.1%. Participation by mail and through the GP was 52.3% (95% CI, 51.3-53.2) and 27.7% (95% CI, 26.7-28.6), respectively. The difference of 24.6% was statistically significant (95% CI, 23.3-25.9, pCRC screening was almost three times higher for people invited by mail as opposed to people invited through a GP (OR=2.96, 95% CI, 2.78-3.14, pCRC screening than men (OR=1.22, 95% CI, 1.15-1.30, pCRC was diagnosed in 18 (5.7%) individuals. Compliance for follow-up colonoscopy was 72.9%, and did not differ between the mail (72.4%, 95% CI, 67.5-77.3) and GP groups (74.3, 95% CI, 66.2-82.5). Inviting people for CRC screening by means of a direct-mail invitation, and including a faecal sampling set (iFOBT), results in much higher participation rates than inviting people through the GP. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Occupational self-coding and automatic recording (OSCAR): a novel web-based tool to collect and code lifetime job histories in large population-based studies.

    Science.gov (United States)

    De Matteis, Sara; Jarvis, Deborah; Young, Heather; Young, Alan; Allen, Naomi; Potts, James; Darnton, Andrew; Rushton, Lesley; Cullinan, Paul

    2017-03-01

    Objectives The standard approach to the assessment of occupational exposures is through the manual collection and coding of job histories. This method is time-consuming and costly and makes it potentially unfeasible to perform high quality analyses on occupational exposures in large population-based studies. Our aim was to develop a novel, efficient web-based tool to collect and code lifetime job histories in the UK Biobank, a population-based cohort of over 500 000 participants. Methods We developed OSCAR (occupations self-coding automatic recording) based on the hierarchical structure of the UK Standard Occupational Classification (SOC) 2000, which allows individuals to collect and automatically code their lifetime job histories via a simple decision-tree model. Participants were asked to find each of their jobs by selecting appropriate job categories until they identified their job title, which was linked to a hidden 4-digit SOC code. For each occupation a job title in free text was also collected to estimate Cohen's kappa (κ) inter-rater agreement between SOC codes assigned by OSCAR and an expert manual coder. Results OSCAR was administered to 324 653 UK Biobank participants with an existing email address between June and September 2015. Complete 4-digit SOC-coded lifetime job histories were collected for 108 784 participants (response rate: 34%). Agreement between the 4-digit SOC codes assigned by OSCAR and the manual coder for a random sample of 400 job titles was moderately good [κ=0.45, 95% confidence interval (95% CI) 0.42-0.49], and improved when broader job categories were considered (κ=0.64, 95% CI 0.61-0.69 at a 1-digit SOC-code level). Conclusions OSCAR is a novel, efficient, and reasonably reliable web-based tool for collecting and automatically coding lifetime job histories in large population-based studies. Further application in other research projects for external validation purposes is warranted.