Future Orientation as a Cross-Cutting Protective Factor Against Multiple Forms of Violence.

Among 9th-to 12th-grade students who completed an anonymous health risk and protective behavior survey (n = 2346), positive future orientation was significantly and inversely associated with multiple forms of interpersonal violence including youth, community, and sexual/relationship violence. Designing interventions to promote future orientation holds promise as a cross-cutting violence prevention strategy.

Composite neonatal morbidity indicators using hospital discharge data: A systematic review.

BACKGROUND: Neonatal morbidity is associated with lifelong impairments, but the absence of a consensual definition and the need for large data sets limit research. OBJECTIVES: To inform initiatives to define standard outcomes for research, we reviewed composite neonatal morbidity indicators derived from routine hospital discharge data. DATA SOURCES: PubMed (updated on October 12, 2018). The search algorithm was based on three components: "morbidity," "neonatal," and "hospital discharge data." STUDY SELECTION AND DATA EXTRACTION: Studies investigating neonatal morbidity using a composite indicator based on hospital discharge data were included. Indicators defined for specific conditions (eg congenital anomalies, maternal addictions) were excluded. The target population, objectives, component morbidities, diagnosis and procedure codes, validation methods, and prevalence of morbidity were extracted. SYNTHESIS: For each study, we assessed construct validity by describing the methods used to select the indicator components and evaluated whether the authors assessed internal and external validity. We also calculated confidence intervals for the prevalence of the morbidity composite. RESULTS: Seventeen studies fulfilled inclusion criteria. Indicators targeted all (n = 4), low-/moderate-risk (n = 9), and very preterm (VPT, n = 4) infants. Components were similar for VPT infants, but domains and diagnosis codes within domains varied widely for all and low-/moderate-risk infants. Component selection was described for 8/17 indicators and some form of validation reported for 12/17. Neonatal morbidity prevalence ranged from 4.6% to 9.0% of all infants, 0.4% to 8.0% of low-/moderate-risk infants, and 17.8% to 61.0% of VPT infants. CONCLUSIONS: Multiple neonatal morbidity indicators based on hospital discharge data have been used for research, but their heterogeneity limits comparisons between studies. Standard neonatal outcome measures are needed for benchmarking and synthesis of research results.

Thoracic imaging tests for the diagnosis of COVID-19.

BACKGROUND: The respiratory illness caused by SARS-CoV-2 infection continues to present diagnostic challenges. Early research showed thoracic (chest) imaging to be sensitive but not specific in the diagnosis of coronavirus disease 2019 (COVID-19). However, this is a rapidly developing field and these findings need to be re-evaluated in the light of new research. This is the first update of this 'living systematic review'. This update focuses on people suspected of having COVID-19 and excludes studies with only confirmed COVID-19 participants. OBJECTIVES: To evaluate the diagnostic accuracy of thoracic imaging (computed tomography (CT), X-ray and ultrasound) in people with suspected COVID-19. SEARCH METHODS: We searched the COVID-19 Living Evidence Database from the University of Bern, the Cochrane COVID-19 Study Register, The Stephen B. Thacker CDC Library, and repositories of COVID-19 publications through to 22 June 2020. We did not apply any language restrictions. SELECTION CRITERIA: We included studies of all designs that recruited participants of any age group suspected to have COVID-19, and which reported estimates of test accuracy, or provided data from which estimates could be computed. When studies used a variety of reference standards, we retained the classification of participants as COVID-19 positive or negative as used in the study. DATA COLLECTION AND ANALYSIS: We screened studies, extracted data, and assessed the risk of bias and applicability concerns using the QUADAS-2 domain-list independently, in duplicate. We categorised included studies into three groups based on classification of index test results: studies that reported specific criteria for index test positivity (group 1); studies that did not report specific criteria, but had the test reader(s) explicitly classify the imaging test result as either COVID-19 positive or negative (group 2); and studies that reported an overview of index test findings, without explicitly classifying the imaging test as either COVID-19 positive or negative (group 3). We presented the results of estimated sensitivity and specificity using paired forest plots, and summarised in tables. We used a bivariate meta-analysis model where appropriate. We presented uncertainty of the accuracy estimates using 95% confidence intervals (CIs). MAIN RESULTS: We included 34 studies: 30 were cross-sectional studies with 8491 participants suspected of COVID-19, of which 4575 (54%) had a final diagnosis of COVID-19; four were case-control studies with 848 cases and controls in total, of which 464 (55%) had a final diagnosis of COVID-19. Chest CT was evaluated in 31 studies (8014 participants, 4224 (53%) cases), chest X-ray in three studies (1243 participants, 784 (63%) cases), and ultrasound of the lungs in one study (100 participants, 31 (31%) cases). Twenty-six per cent (9/34) of all studies were available only as preprints. Nineteen studies were conducted in Asia, 10 in Europe, four in North America and one in Australia. Sixteen studies included only adults, 15 studies included both adults and children and one included only children. Two studies did not report the ages of participants. Twenty-four studies included inpatients, four studies included outpatients, while the remaining six studies were conducted in unclear settings. The majority of included studies had a high or unclear risk of bias with respect to participant selection, index test, reference standard, and participant flow. For chest CT in suspected COVID-19 participants (31 studies, 8014 participants, 4224 (53%) cases) the sensitivity ranged from 57.4% to 100%, and specificity ranged from 0% to 96.0%. The pooled sensitivity of chest CT in suspected COVID-19 participants was 89.9% (95% CI 85.7 to 92.9) and the pooled specificity was 61.1% (95% CI 42.3 to 77.1). Sensitivity analyses showed that when the studies from China were excluded, the studies from other countries demonstrated higher specificity compared to the overall included studies. When studies that did not classify index tests as positive or negative for COVID-19 (group 3) were excluded, the remaining studies (groups 1 and 2) demonstrated higher specificity compared to the overall included studies. Sensitivity analyses limited to cross-sectional studies, or studies where at least two reverse transcriptase polymerase chain reaction (RT-PCR) tests were conducted if the first was negative, did not substantively alter the accuracy estimates. We did not identify publication status as a source of heterogeneity. For chest X-ray in suspected COVID-19 participants (3 studies, 1243 participants, 784 (63%) cases) the sensitivity ranged from 56.9% to 89.0% and specificity from 11.1% to 88.9%. The sensitivity and specificity of ultrasound of the lungs in suspected COVID-19 participants (1 study, 100 participants, 31 (31%) cases) were 96.8% and 62.3%, respectively. We could not perform a meta-analysis for chest X-ray or ultrasound due to the limited number of included studies. AUTHORS' CONCLUSIONS: Our findings indicate that chest CT is sensitive and moderately specific for the diagnosis of COVID-19 in suspected patients, meaning that CT may have limited capability in differentiating SARS-CoV-2 infection from other causes of respiratory illness. However, we are limited in our confidence in these results due to the poor study quality and the heterogeneity of included studies. Because of limited data, accuracy estimates of chest X-ray and ultrasound of the lungs for the diagnosis of suspected COVID-19 cases should be carefully interpreted. Future diagnostic accuracy studies should pre-define positive imaging findings, include direct comparisons of the various modalities of interest on the same participant population, and implement improved reporting practices. Planned updates of this review will aim to: increase precision around the accuracy estimates for chest CT (ideally with low risk of bias studies); obtain further data to inform accuracy of chest X-rays and ultrasound; and obtain data to further fulfil secondary objectives (e.g. 'threshold' effects, comparing accuracy estimates across different imaging modalities) to inform the utility of imaging along different diagnostic pathways.

Two-tailed asymptotic inferences for the odds ratio in cross-sectional studies: evaluation of fifteen old and new methods of inference.

Various asymptotic methods of obtaining a confidence interval (CI) for the odds ratio (OR) have been proposed. Surprisingly, insofar as we know, the behavior of these methods has not been evaluated for data proceeding from a cross-sectional study (multinomial sampling), but only for data that originate in a prospective or retrospective study (two independent binomials sampling). The paper evaluates 15 different methods (10 classic ones and 5 new ones). Because the CI is obtained by inversion in θ of the two-tailed test for H0(θ): OR =[Formula: see text] (null hypothesis), this paper evaluates the tests for various values of θ, more than the CIs that are obtained. The following statements are valid only for the two-tailed inferences based on 20 ≤ n ≤ 200 and 0.05≤ OR≤20, since these are the limitations of the study. The two best methods are the classic Cornfield chi-squared method for 0.2≤ OR≤5 and, in other cases, the new method of Sterne for chi-squared; but the adjusted likelihood ratio method is a good alternative to the two previous methods, especially to the first when the sample size is large. The three methods require iterative calculations to obtain the CI. If one is looking for methods that are simple to apply (that is, ones that admit a simple, explicit solution), the best option is the Gart logit method for 1/3≤ OR≤3 and, if in other cases, the Agresti logit method. The Cornfield chi-squared and Gart logit methods should not be used outside the specified interval OR. The paper also selects the best methods for realizing the classic independence test (θ = 1).

Understanding Aging in Bipolar Disorder by Integrating Archival Clinical Research Datasets.

OBJECTIVE: Although 25% of people with bipolar disorder (BD) are over age 60, there is a dearth of research on older age bipolar disorder (OABD). This report describes an initial effort to create an integrated OABD database using the U.S. National Institute of Mental Health Data Archive (NDA). Goals were to: 1) combine data from three BD studies in the United States that included overlapping data elements; 2) investigate research questions related to aims of the original studies; and 3) take an important first step toward combining existing datasets relevant to aging and BD. METHODS: Data were prepared and uploaded to the NDA, with a focus on data elements common to all studies. As appropriate, data were harmonized to select or collapse categories suitable for cross-walk analysis. Associations between age, BD symptoms, functioning, medication load, medication adherence, and medical comorbidities were assessed. The total sample comprised 451 individuals, mean age 57.7 (standard deviation: 13.1) years. RESULTS: Medical comorbidity was not significantly associated with either age or functioning and there did not appear to be an association between medication load, comorbidity, age, and adherence. Men and African-Americans were significantly more likely to have poor adherence. Both BD mania and depression symptoms were associated with functioning, but this differed across studies. CONCLUSION: Despite limitations including heterogeneity in study design and samples and cross-sectional methodology, integrated datasets represent an opportunity to better understand how aging may impact the presentation and evolution of chronic mental health disorders across the lifespan.

Lipid Profile and Risk of Bone Fracture: A Systematic Review and Meta-Analysis of Observational Studies.

Purpose: Earlier studies have linked lipid profile to osteoporotic fractures; however, to our knowledge, no study had summarized available data on this relationship. We aimed to summarize the current evidence on the association between lipid profile and bone fractures. Material and Methods: A systematic search of PubMed and Scopus was done to find relevant published studies until March 2018. To combine effect sizes, we applied fixed- or random-effects analysis, where appropriate. Cochran's Q test and I2 were used to assess between-study heterogeneity. Results: Overall, 11 studies (seven prospective, three cross-sectional and one case-control studies) were included in the current systematic review. Out of them, 10 studies with a total sample size of 60,484 individuals, aged 25 years or more, were used in the meta-analysis. The results showed that total cholesterol concentration was positively associated with risk of bone fracture; such that a 50-mg/dl increase in plasma level of TC was associated with 15% greater odds of bone fracture (combined effect size: 1.15, 95% CI: 1.02-1.30, P = .02). Furthermore, we found that individuals with a decreased level of HDL (<40 mg/dl) had a lower risk of bone fracture compared with those with a normal level (≥40 mg/dl) (combined effect size: 0.82, 95% CI: 0.71-0.96, P = .01). No significant association was found between plasma level of TG and LDL with the risk of bone fractures either in prospective or cross-sectional studies. Conclusions: We found that plasma levels of total cholesterol were positively associated with bone fractures. In addition, decreased levels of HDL were associated with an increased risk of osteoporotic fractures. Abbreviations: TG: triglycerides, TC: total cholesterol, HDL: high-density lipoprotein, LDL: low-density lipoprotein, OR: odds ratio, RR: relative risk, HR: hazard ratio, DXA: dual-energy X-ray absorptiometry, ICD: International Classification of Diseases, SD: standard deviation.

A change in the prevalence and the etiological factors of chronic wounds in Helsinki metropolitan area during 2008-2016.

The prevalence of chronic wounds in the Helsinki metropolitan area in 2008 was investigated. Thereafter, a specialised wound care team was founded as part of the City of Helsinki Health Services, aiming for early diagnoses of chronic wounds. In the current study, we have repeated the prevalence study to analyse the changes in the prevalence of chronic wounds. A questionnaire on wound patients was sent to all units of social and health care in the Helsinki metropolitan area. We asked about the number of patients with wounds treated during a 24-hour period, as well the aetiology and location of the wounds. A total of 911 patients had, altogether, 1021 wounds. Thus, prevalence was 0.08%. Pressure and multifactorial ulcers were the most common aetiological groups, whereas wound without defined aetiology had diminished greatly (61%) The prevalence of chronic wound decreased when compared with 2008 (0.08% vs 0.1%). The number of elderly people aged over 65 years had increased 35%, and the age-adjusted prevalence had decreased. Wounds are treated mostly in primary care units and as outpatients. Therefore, the following conclusion may be reached: diagnostic process and implementation of treatment paths are strengthened within primary care units, yet prevalence of wounds has decreased.

Cross-sectional versus longitudinal designs for function estimation, with an application to cerebral cortex development.

Motivated by studies of the development of the human cerebral cortex, we consider the estimation of a mean growth trajectory and the relative merits of cross-sectional and longitudinal data for that task. We define a class of relative efficiencies that compare function estimates in terms of aggregate variance of a parametric function estimate. These generalize the classical design effect for estimating a scalar with cross-sectional versus longitudinal data, and are shown to be bounded above by it in certain cases. Turning to nonparametric function estimation, we find that longitudinal fits may tend to have higher aggregate variance than cross-sectional ones, but that this may occur because the former have higher effective degrees of freedom reflecting greater sensitivity to subtle features of the estimand. These ideas are illustrated with cortical thickness data from a longitudinal neuroimaging study.

Insights on Allergic Rhinitis Management from a Northern Cyprus Perspective and Evaluation of the Impact of Pharmacist-Led Educational Intervention on Patients' Outcomes.

BACKGROUND AND OBJECTIVE: the global prevalence of allergic rhinitis (AR) is rising and yet there is scarce information concerning the diagnosis, management and treatment patterns of AR in Northern Cyprus (NC). This study aims to provide a unique perspective on AR management as well as assessing the effectiveness of the pharmacist-led educational intervention for improving care of AR patients. METHODS: across-sectional survey was carried out with community pharmacists (n = 70), patients (n = 138) and ear, nose and throat (ENT) specialists (n = 12) in NC. For a controlled interventional trial, trained pharmacists provided a brief education on management of AR and nasal spray technique for patients while other pharmacists provided the usual care. Quality of life (QoL) and other outcome measures on the perceived symptom severity of the two groups were compared after a 6-week period. RESULTS: only 33.3% of the ear, nose and throat (ENT) specialists and 15.7% of the community pharmacists are aware of the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines. The majority of patients (63%) self-managed with over-the-counter medications. Nasal congestion (96.4%) is the most bothersome symptom and oral antihistamines are the most commonly purchased medications (51.4%), indicating a pattern of suboptimal management. The pharmacists-led educational intervention has resulted in statistically more significant improvement in regards to nasal congestion and QoL for the intervention group patients (p < 0.05). CONCLUSION: the current management of AR has not been in accordance with the ARIA guidelines in NC. An educational intervention of the pharmacists can enhance the symptom management and improve the QoL in patients with AR.

Bibliometrics of Tunisian publications in preventive and community medicine, indexed in the Medline database (1975-2014).

INTRODUCTION: With the aim of rebuilding the memory of the specialty of Preventive Medicine and Community Medicine (MPC) in Tunisia, through its indexed scientific publications, the objective of this work was to describe the thematic and methodological profile of indexed scientific research, of this specialty over four decades. METHODS: This is a descriptive bibliometric study of MPC articles, indexed in the Medline database over a 40-year period (1975-2014), and based on their Medline Material Safety Data Sheets (MSDS). All articles of which the first and / or last authors were MPC university hospital teachers, in one of Tunisia's four faculties of medicine, were included. The themes of the publications were defined through the major keywords (Majr), and categorized according to the following five groups: "non-communicable diseases", "communicable diseases", "violence and traumatisms", "management of health services" and "Research and pedagogy". RESULTS: Among 1664 articles captured by the Medline-based documentary request, 594 had as their first authors, teachers of the MPC specialty and 365 articles were eligible for study. The productivity of the specialty of MPC increased from 29 publications between 1975 and 1984, to 167 between 2005 and 2014. The magazine "La Tunisie Médicale" published 37.6% of the articles of this specialty. Four out of ten MPC papers referred to hospital structures and 35% of them were cross-sectional observational studies. Over the decades, an increase in research topics related to "non-communicable diseases" versus "communicable diseases" has been noted in MPC. CONCLUSION: In Tunisia, research in MPC has been relatively prolific and globally consistent with the health needs of the population (impacted by the epidemiological transition). The orientation of research projects towards community-based proposals, of high methodological level and mobilizing multidisciplinary teams, would be necessary for the improvement of the quality and relevance of publications in MPC.

Time trends of chronic HBV infection over prior decades - A global analysis.

BACKGROUND & AIMS: Information on trends in chronic hepatitis B virus (HBV) prevalence across countries is lacking. We studied changes in chronic HBV infection over previous decades by country, and assessed patterns of change between and within WHO-defined regions. METHODS: Based on data from a published systematic review on chronic HBV, we applied a linear model on the logit scale to assess time trends in country-specific prevalence. Estimated HBsAg prevalence in 2000 and relative changes in prevalence over time were evaluated by country and region. RESULTS: Sufficient data were available for 50 countries, mostly showing reductions in prevalence over time. Various degrees of heterogeneity were observed within regions, with a relatively homogenous pattern in the Eastern Mediterranean region with strong decreases in HBsAg prevalence. Europe showed a mixed pattern: higher and stable chronic HBsAg prevalence in Eastern, and constantly low prevalence in Western Europe. In Africa, some countries demonstrated no change in prevalence; increases were seen in Uganda (odds ratio 1.05 per year; 95% confidence interval 1.04-1.06), Nigeria (1.02; 1.02-1.02), Senegal (1.01; 1.01-1.02), and South Africa (1.02; 1.01-1.02). With some exceptions, country-patterns overlapped among countries of South East Asian and Western Pacific regions, characterized by low-medium HBsAg decreases, most prominent in China and Malaysia. CONCLUSIONS: Most countries experienced decreases in HBsAg prevalence. Dynamics varied, even within regions; decreases occurred mostly before the direct effects of childhood vaccination may have manifested. These findings together with stable and increasing HBsAg prevalence in some countries of Africa and Eastern Europe indicate the need for further tailored country-specific prevention. LAY SUMMARY: This study investigated time trends in prevalence of chronic HBV infection in 50 countries worldwide over the last decade, by estimating relative changes in prevalence. Results show decreases in chronic HBV infection in most countries; no changes or increases in prevalence are noted in some African countries. Reasons for time changes need to be investigated further; based on the results, various prevention measures have contributed to reductions, and further tailored HBV prevention is required to combat the disease on a global level.

A Bayesian approach to model the conditional correlation between several diagnostic tests and various replicated subjects measurements.

Two key aims of diagnostic research are to accurately and precisely estimate disease prevalence and test sensitivity and specificity. Latent class models have been proposed that consider the correlation between subject measures determined by different tests in order to diagnose diseases for which gold standard tests are not available. In some clinical studies, several measures of the same subject are made with the same test under the same conditions (replicated measurements), and thus, replicated measurements for each subject are not independent. In the present study, we propose an extension of the Bayesian latent class Gaussian random effects model to fit the data with binary outcomes for tests with replicated subject measures. We describe an application using data collected on hookworm infection carried out in the municipality of Presidente Figueiredo, Amazonas State, Brazil. In addition, the performance of the proposed model was compared with that of current models (the subject random effects model and the conditional (in)dependent model) through a simulation study. As expected, the proposed model presented better accuracy and precision in the estimations of prevalence, sensitivity and specificity. Copyright © 2017 John Wiley & Sons, Ltd.

The Elusive Nature of APOE ε4 in Mid-adulthood: Understanding the Cognitive Profile.

OBJECTIVES: The apolipoprotein E (APOE) ε4 allele is an established risk factor for dementia, yet this genetic variant is associated with a mixed cognitive profile across the lifespan. This study undertakes both a systematic and meta-analytic review of research investigating APOE-related differences in cognition in mid-adulthood, when detrimental effects of the allele may first be detectable. METHODS: Thirty-six papers investigating the behavioral effects of APOE ε4 in mid-adulthood (defined as a mean sample age between 35 and 60 years) were reviewed. In addition, the effect of carrying an ε4 allele on individual cognitive domains was assessed in separate meta-analyses. RESULTS: The average effect size of APOE ε4 status was non-significant across cognitive domains. Further consideration of genotype effects indicates preclinical effects of APOE ε4 may be observable in memory and executive functioning. CONCLUSIONS: The cognitive profile of APOE ε4 carriers at mid-age remains elusive. Although there is support for comparable performance by ε4 and non-e4 carriers in the 5th decade, studies administering sensitive cognitive paradigms indicate a more nuanced profile of cognitive differences. Methodological issues in this field preclude strong conclusions, which future research must address, as well as considering the influence of further vulnerability factors on genotype effects. (JINS, 2016, 23, 239-253).

VI. PERSON-SPECIFIC INDIVIDUAL DIFFERENCE APPROACHES IN DEVELOPMENTAL RESEARCH.

In this chapter, we demonstrate the way certain common analytic approaches (e.g., polynomial curve modeling, repeated measures ANOVA, latent curve, and other factor models) create individual difference measures based on a common underlying model. After showing that these approaches require only means and covariance (or correlation) matrices to estimate regression coefficients based on a hypothesized model, we describe how to recast these models based on time-series related approaches focusing on single subject time series approaches (e.g., vector autoregressive approaches and P-technique factor models). We show how these latter methods create parameters based on models that can vary from individual-to-individual. We demonstrate differences for the factor model using real data examples.

Design-based inference in time-location sampling.

Time-location sampling (TLS), also called time-space sampling or venue-based sampling is a sampling technique widely used in populations at high risk of infectious diseases. The principle is to reach individuals in places and at times where they gather. For example, men who have sex with men meet in gay venues at certain times of the day, and homeless people or drug users come together to take advantage of services provided to them (accommodation, care, meals). The statistical analysis of data coming from TLS surveys has been comprehensively discussed in the literature. Two issues of particular importance are the inclusion or not of sampling weights and how to deal with the frequency of venue attendance (FVA) of individuals during the course of the survey. The objective of this article is to present TLS in the context of sampling theory, to calculate sampling weights and to propose design-based inference taking into account the FVA. The properties of an estimator ignoring the FVA and of the design-based estimator are assessed and contrasted both through a simulation study and using real data from a recent cross-sectional survey conducted in France among drug users. We show that the estimators of prevalence or a total can be strongly biased if the FVA is ignored, while the design-based estimator taking FVA into account is unbiased even when declarative errors occur in the FVA.

Sample size methods for estimating HIV incidence from cross-sectional surveys.

Understanding HIV incidence, the rate at which new infections occur in populations, is critical for tracking and surveillance of the epidemic. In this article, we derive methods for determining sample sizes for cross-sectional surveys to estimate incidence with sufficient precision. We further show how to specify sample sizes for two successive cross-sectional surveys to detect changes in incidence with adequate power. In these surveys biomarkers such as CD4 cell count, viral load, and recently developed serological assays are used to determine which individuals are in an early disease stage of infection. The total number of individuals in this stage, divided by the number of people who are uninfected, is used to approximate the incidence rate. Our methods account for uncertainty in the durations of time spent in the biomarker defined early disease stage. We find that failure to account for this uncertainty when designing surveys can lead to imprecise estimates of incidence and underpowered studies. We evaluated our sample size methods in simulations and found that they performed well in a variety of underlying epidemics. Code for implementing our methods in R is available with this article at the Biometrics website on Wiley Online Library.

Marginal genetic effects estimation in family and twin studies using random-effects models.

Random-effects models are often used in family-based genetic association studies to properly capture the within families relationships. In such models, the regression parameters have a conditional on the random effects interpretation and they measure, e.g., genetic effects for each family. Estimating parameters that can be used to make inferences at the population level is often more relevant than the family-specific effects, but not straightforward. This is mainly for two reasons: First the analysis of family data often requires high-dimensional random-effects vectors to properly model the familial relationships, for instance when members with a different degree of relationship are considered, such as trios, mix of monozygotic and dizygotic twins, etc. The second complication is the biased sampling design, such as the multiple cases families design, which is often employed to enrich the sample with genetic information. For these reasons deriving parameters with the desired marginal interpretation can be challenging. In this work we consider the marginalized mixed-effects models, we discuss challenges in applying them in ascertained family data and propose penalized maximum likelihood methodology to stabilize the parameter estimation by using external information on the disease prevalence or heritability. The performance of our methodology is evaluated via simulation and is illustrated on data from Rheumatoid Arthritis patients, where we estimate the marginal effect of HLA-DRB1*13 and shared epitope alleles across three different study designs and combine them using meta-analysis.

A tale of two epidemics: gender differences in socio-demographic characteristics and sexual behaviors among HIV positive individuals in Mexico City.

BACKGROUND: To date, the HIV epidemic in Mexico has been concentrated mainly among men who have sex with men, butheterosexual transmission, particularly to women, is increasingly important. This study examine gender differences in socio-demographic characteristics and risk behaviors of HIV positive individuals in Mexico City. METHODS: We analyzed data from a cross-sectional survey of 1,490 clinic patients (male:female ratio 8:1) with HIV inMexico City in 2010. We examined socio-demographic characteristics, risk behavior, and history of HIV infection.From multivariate non-linear probability (probit) models we calculated predicted probabilities by sex of several outcomes: marginalization, demographic and sexual risk behaviors. RESULTS: Significant differences were found between men and women. Multivariate models suggest that women had lower schooling levels; were less likely to have been employed in the past month and earn more than the minimal wage; more likely to have children, to have been sexually abused, to never have used condoms and to report having been infected by a stable partner. Additionally, women were less likely to report having a partner with a history of migration to the USA and to have engaged in transactional sex. CONCLUSION: Significant differences exist between men and women with HIV in Mexico City in terms of their socioeconomicand behavioral profiles, which translate into differences in terms of exposure to HIV infection. Women face social and economic vulnerability while men tend to have riskier sexual behavior. Gender issues must be approached in prevention and treatment efforts, using diverse methods to target those most vulnerable and at risk.

Cognition and the risk of eating disorders in Spanish adolescents: the AVENA and AFINOS studies.

UNLABELLED: Eating disorders (ED) can arise from a combination of biological and psychological factors. Some studies suggest that intellectual factors might be important in the development of ED, although the evidence is still scarce. The aim of this study was to examine the association between cognition measurements (cognitive performance and academic achievement) and the risk of developing ED in adolescents considering their weight status. The sample consisted of 3,307 adolescents (1,756 girls), aged 13-18.5 years, who participated in the AVENA (n = 1,430; 783 girls) and AFINOS (n = 1,877; 973 girls) studies. Cognitive performance was measured by the TEA test in the AVENA study, and academic achievement was self-reported in the AFINOS study. ED risk was evaluated in both studies by using the SCOFF questionnaire. Body mass index was calculated to classify adolescents as non-overweight or overweight (including obesity). Overweight adolescents showed a higher risk of developing ED than non-overweight ones in both studies. In the AVENA study, overweight boys with low performance in reasoning ability showed increased risk of ED (p = 0.05). In the AFINOS study, overweight boys with low academic performance in physical education and non-overweight girls with low academic achievement in all the areas analyzed showed higher risk of ED than their peers (all p < 0.05). CONCLUSION: No association between cognitive performance and ED risk was found in adolescents, while academic achievement was associated with ED risk, especially in non-overweight girls. The non-cognitive traits that accompany academic achievement could influence the likelihood of developing ED in these girls.