56 research outputs found

    Comparing population distributions from bin-aggregated sample data: An application to historical height data from France

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    This paper develops a methodology to estimate the entire population distributions from bin-aggregated sample data. We do this through the estimation of the parameters of mixtures of distributions that allow for maximal parametric flexibility. The statistical approach we develop enables comparisons of the full distributions of height data from potential army conscripts across France's 88 departments for most of the nineteenth century. These comparisons are made by testing for differences-of-means stochastic dominance. Corrections for possible measurement errors are also devised by taking advantage of the richness of the data sets. Our methodology is of interest to researchers working on historical as well as contemporary bin-aggregated or histogram-type data, something that is still widely done since much of the information that is publicly available is in that form, often due to restrictions due to political sensitivity and/or confidentiality concerns.Health, health inequality, aggregate data, 19th-century France, welfare

    Santé et conditions de vie dans la France du dix-neuvième siècle

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    Tableau d’honneur de la Faculté des études supérieures et postdoctorales, 2007-2008

    Effets des phospholipides alimentaires sur le métabolisme des lipides du plasma et du foie, ainsi que sur la sécrétion des lipides biliaires chez le rat

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    Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

    BENEFICIAL AND PEST INSECTS ASSOCIATED WITH TEN FLOWERING PLANT SPECIES GROWN IN QUÉBEC, CANADA

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    Preventive measures are very important in organic agriculture to minimize pest problems. Conservation biological control is one preventive approach. It includes habitat manipulation through which the agroecosystem may be designed to encourage the activity of beneficial insects. The use of flowering strips is one way to do that. This 3-year study was performed on the Organic Agriculture Innovation Platform in Saint-Bruno-de-Montarville, Québec. Canada. It comprises data on insect abundance and composition on ten flowering plant species. Data are collected on beneficial insects such as coccinellid predators and predatory bugs. Are also included in this study observations and counts of insect pests which could also be attracted to this flowering plant species and build up in numbers close to the crop which we are aiming to protect

    Comparing Population Distributions from bin-Aggregated Sample Data: an Application to Historical Height Data from France

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    This paper develops a methodology to estimate the entire population distributions from bin-aggregated sample data. We do this through the estimation of the parameters of mixtures of distributions that allow for maximal parametric flexibility. The statistical approach we develop enables comparisons of the full distributions of height data from potential army conscripts across France's 88 departments for most of the nineteenth century. These comparisons are made by testing for differences-of-means stochastic dominance. Corrections for possible measurements errors are also devised by taking advantage of the richness of the data sets. Our methodology is of interest to researchers working on historical as well as contemporary bin-aggregated or histogram-type data, something that is still widely done since much of the information that is publicly available is in that form, often due to restrictions due to political sensitivity and/or confidentiality concerns

    Prevalence of insomnia and its treatment in Canada

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    Objectives : To estimate the prevalence of insomnia and examine its correlates (for example, demographics and physical and mental health) and treatments. Methods : A sample of 2000 Canadians aged 18 years and older responded to a telephone survey about sleep, health, and the use of sleep-promoting products. Respondents with insomnia were identified using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, and the International Classification of Diseases, Tenth Edition, criteria. Results : Among the sample, 40.2% presented at least 1 symptom of insomnia (that is, trouble falling or staying asleep, or early morning awakening) for a minimum of 3 nights per week in the previous month, 19.8% were dissatisfied with their sleep, and 13.4% met all criteria for insomnia (that is, presence of 1 insomnia symptom 3 nights or more per week for at least 1 month, accompanied by distress or daytime impairment). Insomnia was associated with female sex, older age, and poorer self-rated physical and mental health. Thirteen per cent of respondents had consulted a health care provider for sleep difficulties once in their lifetime. Moreover, 10% had used prescribed medications for sleep in the previous year, 9.0% used natural products, 5.7% used over-the-counter products, and 4.6% used alcohol. There were differences between French- and English-speaking adults, with the former group presenting lower rates of insomnia (9.5%, compared with 14.3%) and consultation (8.7%, compared with 14.4%), but higher rates of prescribed medications (12.9%, compared with 9.3%) and the use of natural products (15.6%, compared with 7.4%). Conclusions : Insomnia is a prevalent condition, although few people seek professional consultation for this condition. Despite regional differences in the prevalence and treatments used to manage insomnia, prescribed medications remain the most widely used therapeutic option.Objectifs : Estimer la prévalence de l'insomnie et examiner ses corrélats (par exemple, les données démographiques et la santé physique et mentale) et les traitements. Méthodes : Un échantillon de 2000 Canadiens de 18 ans et plus ont répondu à une enquête téléphonique sur le sommeil, la santé et l'utilisation de produits qui favorisent le sommeil. Les répondants souffrant d'insomnie ont été identifiés à l'aide des critères du Manuel diagnostique et statistique des troubles mentaux, 4e édition révisée, et de la Classification internationale des maladies, 10e édition. Résultats : Dans l'échantillon, 40,2 % présentaient au moins 1 symptôme d'insomnie (c'est-à-dire, difficulté à s'endormir ou à rester endormi, ou réveil tôt le matin) pour un minimum de 3 nuits par semaine durant le mois précédent, 19,8 % étaient insatisfaits de leur sommeil, et 13,4 % satisfaisaient à tous les critères de l'insomnie (c'est-à-dire, la présence d'un symptôme d'insomnie 3 nuits ou plus par semaine pendant au moins 1 mois, accompagnée de détresse ou d'incapacité durant le jour). L'insomnie était associée avec le sexe féminin, l'âge avancé, et une mauvaise santé physique et mentale auto-déclarée. Treize pour cent des répondants avaient consulté un prestataire de soins de santé pour des difficultés de sommeil une fois dans leur vie. En outre, 10 % avaient utilisé des médicaments prescrits pour le sommeil dans l'année précédente, 9,0 % avaient utilisé des produits naturels, 5,7 % avaient utilisé des produits en vente libre, et 4,6 % avaient utilisé de l'alcool. Il y avait des différences entre les adultes francophones et anglophones, le premier groupe présentant des taux plus faibles d'insomnie (9,5 %, comparé à 14,3 %) et de consultations (8,7 %, comparé à 14,4 %), mais des taux plus élevés de médicaments prescrits (12,9 %, comparé à 9,3 %) et d'utilisation de produits naturels (15,6 %, comparé à 7,4 %). Conclusions : L'insomnie est une affection prévalente, bien que peu de gens aient recours à une consultation professionnelle pour ce problème. Malgré des différences régionales de prévalence et des traitements utilisés pour gérer l'insomnie, les médicaments prescrits demeurent l'option thérapeutique la plus utilisée

    Insomnia and its relationship to health-care utilization, work absenteeism, productivity and accidents

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    Background and purpose To document and provide a micro analysis of the relationship between insomnia and health problems, health-care use, absenteeism, productivity and accidents. Participants and methods A population-based sample of 953 French-speaking adults from Québec, Canada. Participants were categorized as having insomnia syndrome (SYND) or insomnia symptoms (SYMPT) or as good sleepers (GS). They completed questionnaires on sleep, health, use of health-care services and products, accidents, work absences and reduced work productivity. Data were also obtained from the Québec-government-administered health insurance board on selected variables (e.g., consultations with health-care professionals, diagnoses). Results There were significantly more individuals in the SYND group relative to the GS group reporting at least one chronic health problem (83% vs. 53%; OR: 2.78) and who had consulted a health-care professional in the past year (81% vs. 60%; OR: 2.8). There were also higher proportions of individuals in the SYND group than in the GS group who had used prescription medications (57% vs. 30.7%; OR: 2.8), most notably to treat insomnia, mood and anxiety disorders, or who had used over-the-counter products (75.6% vs. 62.0%; OR: 1.8) and alcohol as a sleep aid (17.8% vs. 3.9%; OR: 4.6). In terms of daytime function, 25.0% of the SYND had been absent from work relative to 17.1% of GS (OR: 1.7), 40.6% reported having experienced reduced productivity compared to 12.3% of GS (OR: 4.8) and non-motor-vehicle accidents occurred at higher rates in the SYND group (12.5% vs. 6.4% for GS; OR: 2.4). No differences were found for hospitalisations or motor-vehicle accidents. Most of the associations remained significant even after controlling for psychiatric comorbidity. Rates for the SYMPT group were situated between SYND and GS on all major dependent variables. Furthermore, insomnia and fatigue were perceived as contributing significantly to accidents, absences and decreased work productivity, regardless of insomnia status. Conclusions This study indicates that insomnia is associated with significant morbidity in terms of health problems and health-care utilization, work absenteeism and reduced productivity, and risk of non-motor-vehicle accidents. Future studies should evaluate whether treating insomnia can reverse this morbidity

    Monthly fluctuations of insomnia symptoms in a population-based sample

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    Study Objectives: 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. Design: 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. Results: 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 reliable for defining chronic insomnia. Conclusions: Monthly assessment of insomnia and sleep patterns revealed significant variability over the course of a 12-month period. These findings highlight the importance for future epidemiological studies of conducting repeated assessment at shorter than the typical yearly interval in order to reliably capture the natural course of insomnia over time

    Comparing population distributions from bin-aggregated sample data : an application to historical height data from France

    Get PDF
    This paper develops a methodology to estimate the entire population distributions from bin-aggregated sample data. We do this through the estimation of the parameters of mixtures of distributions that allow for maximal parametric flexibility. The statistical approach we develop enables comparisons of the full distributions of height data from potential army conscripts across France's 88 departments for most of the nineteenth century. These comparisons are made by testing for differences-of-means stochastic dominance. Corrections for possible measurement errors are also devised by taking advantage of the richness of the data sets. Our methodology is of interest to researchers working on historical as well as contemporary bin-aggregated or histogram-type data, something that is still widely done since much of the information that is publicly available is in that form, often due to restrictions due to political sensitivity and/or confidentiality concerns

    The natural history of insomnia : a population-based 3-year longitudinal study

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    Background Despite its high prevalence, little information is available about the natural history of insomnia. The extent to which episodes of insomnia will persist or remit over time is difficult to predict. We examined the natural history of insomnia and describe the most common trajectories over 3 years. Methods Three hundred eighty-eight adults (mean [SD] age, 44.8 [13.9] years; 61% women) were selected from a larger population-based sample on the basis of the presence of insomnia at baseline. They completed standardized sleep/insomnia questionnaires at 3 annual follow-up assessments. For each follow-up assessment, participants were classified into 1 of 3 groups (individuals with an insomnia syndrome, individuals with insomnia symptoms, and individuals with good sleep) on the basis of algorithms using standard diagnostic criteria for insomnia. Rates of persistent insomnia, remission, and relapse were computed for each group. Results Of the study sample, 74% reported insomnia for at least 1 year (2 consecutive assessments) and 46% reported insomnia persisting over the entire 3-year study. The course of insomnia was more likely to be persistent in those with more severe insomnia at baseline (ie, insomnia syndrome) and in women and older adults. Remission rate was 54%; however, 27% of those with remission of insomnia eventually experienced relapse. Individuals with subsyndromal insomnia at baseline were 3 times more likely to remit than worsen to syndrome status, although persistence was the most frequent course in that group as well. Conclusion These findings indicate that insomnia is often a persistent condition, in particular when it reaches the diagnostic threshold for an insomnia disorder
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