Random Subsample Research Articles

The effect of disease misclassification on the ability to detect a gene-environment interaction: implications of the specificity of case definitions for research on Gulf War illness

BackgroundSince 1997, research on Gulf War illness (GWI) has predominantly used 3 case definitions—the original Research definition, the CDC definition, and modifications of the Kansas definition—but they have not been compared against an objective standard.MethodsAll 3 case definitions were measured in the U.S. Military Health Survey by a computer-assisted telephone interview in a random sample (n = 6,497) of the 1991 deployed U.S. military force. The interview asked whether participants had heard nerve agent alarms during the conflict. A random subsample (n = 1,698) provided DNA for genotyping the PON1 Q192R polymorphism.ResultsThe CDC and the Modified Kansas definition without exclusions were satisfied by 41.7% and 39.0% of the deployed force, respectively, and were highly overlapping. The Research definition, a subset of the others, was satisfied by 13.6%. The majority of veterans meeting CDC and Modified Kansas endorsed fewer and milder symptoms; whereas, those meeting Research endorsed more symptoms of greater severity. The group meeting Research was more highly enriched with the PON1 192R risk allele than those meeting CDC and Modified Kansas, and Research had twice the power to detect the previously described gene-environment interaction between hearing alarms and RR homozygosity (adjusted relative excess risk due to interaction [aRERI] = 7.69; 95% CI 2.71–19.13) than CDC (aRERI = 2.92; 95% CI 0.96–6.38) or Modified Kansas without exclusions (aRERI = 3.84; 95% CI 1.30–8.52) or with exclusions (aRERI = 3.42; 95% CI 1.20–7.56). The lower power of CDC and Modified Kansas relative to Research was due to greater false-positive disease misclassification from lower diagnostic specificity.ConclusionsThe original Research case definition had greater statistical power to detect a genetic predisposition to GWI. Its greater specificity favors its use in hypothesis-driven research; whereas, the greater sensitivity of the others favor their use in clinical screening for application of future diagnostic biomarkers and clinical care.

Exploring Demographic and Clinical Characteristics of Racially and Ethnically Diverse Youth With Eating Disorders Using California Medicaid Claims Data

To explore the scope of diagnosed eating disorders among Medicaid-insured youth in California, and to describe the demographic characteristics of this population in a repeated annual cross-sectional study design. California Medicaid claims data were extracted for youth aged 7 to 18 years between January 2014 and December 2016. Participants included all youth who received an eating disorder diagnosis at any point in the study period (N= 8,075). Additional analyses compared youth with eating disorders who were continuously enrolled across all 3 years (n= 4,500) to random subsamples of continuously enrolled youth diagnosed with a mood or anxiety disorder (n= 4,128), a disruptive behavior disorder (n= 4,599), or a psychotic disorder (n= 4,290). About one-half of youth with eating disorders were Latinx (58.5%, n= 2,634) and indicated Spanish as their preferred language (48.9%, n= 2,199). About one-half (51%, n= 2,301) of eating disorder diagnoses were unspecified. Latinx ethnicity and Spanish language were significantly more frequent among youth with eating disorders than among those with other disorders (F11.97, F362.75, p values<.0005). The first examination of publicly insured youth with eating disorders revealed a highly diverse group of individuals among whom Latinx youth were particularly prevalent. However, past-year national prevalence estimates suggest that most eating disorder cases were undiagnosed. Eating disorders affect approximately 10% of the US population and lead to serious mental health and medical problems. This study used California Medicaid claims data from 2014 to 2016 to characterize the population of youth aged 7 to 18 years with diagnosed with an eating disorder (N = 8,075). The authors found the prevalence of eating disorders among youth aged 13 to 18 years was about 0.20% across all 3 years of the study, which is far below the expected prevalence and suggests that most eating disorders in youth go undiagnosed. About half of eating disorder diagnoses provided to youth with Medicaid insurance are unspecified, which may hinder receipt of appropriate treatment. Of youth with an eating disorder, about half were Latinx and reported Spanish as their preferred language. The authors also found differences in the prevalences of eating disorder diagnoses when analyzing youth by age, sex, and ethnicity. These results suggest that more standardized screening and assessment is needed to improve eating disorders detection and diagnosis, particularly for minoritized youth.

The Chinese Internalized Binegativity Scale: Measure development and cultural adaptation.

This article presents the development and psychometric evaluation of the Chinese Internalized Binegativity Scale (CIBS), the first Chinese-language measure available to examine internalized binegativity (IB) for bisexual people living in Mainland China, Hong Kong, and Taiwan. This measure is based on the translation and cultural adaptation (Sidani et al., 2010) of items from the (English language and U.S. developed) Bisexual Identity Inventory (Paul et al., 2014), as well as the development of novel items based on the prior literature and interviews with six bisexual experts and six bisexual laypersons who reside in Mainland China, Hong Kong, and Taiwan. Preliminary items were administered to 685 bisexual participants living in these three Chinese cultural regions. Exploratory factor analysis with a random subsample (n = 343) yielded a psychometrically robust measurement model consisting of six factors: illegitimacy, monosexism, aversion, irresponsibility, family shame, and identity affirmation, with internal consistency reliability estimates ranging from .76 to .91. This multidimensional factor structure was substantiated by confirmatory factor analysis with the second subsample (n = 342). Furthermore, the CIBS demonstrated satisfactory convergent validity through statistically significant correlations in theoretically predicted directions with the Chinese Internalized Homophobia Scale and Private Collective Self-Esteem subscale. Bifactor modeling was conducted to examine the utility of the scale scores for subsequent use. Higher levels of IB measured by the CIBS were associated with more depressive symptoms, more anxiety, lower levels of coming out to others, lower self-esteem, and lower global life satisfaction. Research implications and limitations are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Frequency of multiple changes to prespecified primary outcomes of clinical trials completed between 2009 and 2017 in German university medical centers: A meta-research study

Background Clinical trial registries allow assessment of deviations of published trials from their protocol, which may indicate a considerable risk of bias. However, since entries in many registries can be updated at any time, deviations may go unnoticed. We aimed to assess the frequency of changes to primary outcomes in different historical versions of registry entries, and how often they would go unnoticed if only deviations between published trial reports and the most recent registry entry are assessed. Methods and findings We analyzed the complete history of changes of registry entries in all 1746 randomized controlled trials completed at German university medical centers between 2009 and 2017, with published results up to 2022, that were registered in ClinicalTrials.gov or the German WHO primary registry (German Clinical Trials Register; DRKS). Data were retrieved on 24 January 2022. We assessed deviations between registry entries and publications in a random subsample of 292 trials. We determined changes of primary outcomes (1) between different versions of registry entries at key trial milestones, (2) between the latest registry entry version and the results publication, and (3) changes that occurred after trial start with no change between latest registry entry version and publication (so that assessing the full history of changes is required for detection of changes). We categorized changes as major if primary outcomes were added, dropped, changed to secondary outcomes, or secondary outcomes were turned into primary outcomes. We also assessed (4) the proportion of publications transparently reporting changes and (5) characteristics associated with changes. Of all 1746 trials, 23% (n = 393) had a primary outcome change between trial start and latest registry entry version, with 8% (n = 142) being major changes, that is, primary outcomes were added, dropped, changed to secondary outcomes, or secondary outcomes were turned into primary outcomes. Primary outcomes in publications were different from the latest registry entry version in 41% of trials (120 of the 292 sampled trials; 95% confidence interval (CI) [35%, 47%]), with major changes in 18% (54 of 292; 95% CI [14%, 23%]). Overall, 55% of trials (161 of 292; 95% CI [49%, 61%]) had primary outcome changes at any timepoint over the course of a trial, with 23% of trials (67 of 292; 95% CI [18%, 28%]) having major changes. Changes only within registry records, with no apparent discrepancy between latest registry entry version and publication, were observed in 14% of trials (41 of 292; 95% CI [10%, 19%]), with 4% (13 of 292; 95% CI [2%, 7%]) being major changes. One percent of trials with a change reported this in their publication (2 of 161 trials; 95% CI [0%, 4%]). An exploratory logistic regression analysis indicated that trials were less likely to have a discrepant registry entry if they were registered more recently (odds ratio (OR) 0.74; 95% CI [0.69, 0.80]; p&lt;0.001), were not registered on ClinicalTrials.gov (OR 0.41; 95% CI [0.23, 0.70]; p = 0.002), or were not industry-sponsored (OR 0.29; 95% CI [0.21, 0.41]; p&lt;0.001). Key limitations include some degree of subjectivity in the categorization of outcome changes and inclusion of a single geographic region. Conclusions In this study, we observed that changes to primary outcomes occur in 55% of trials, with 23% trials having major changes. They are rarely transparently reported in the results publication and often not visible in the latest registry entry version. More transparency is needed, supported by deeper analysis of registry entries to make these changes more easily recognizable. Protocol registration: Open Science Framework (https://osf.io/t3qva; amendment in https://osf.io/qtd2b).

Portuguese Heart Failure Prevalence Observational Study (PORTHOS) rationale and design – A population-based study

Introduction and objectivesCurrent epidemiological data on heart failure (HF) in Portugal derives from studies conducted two decades ago. The main aim of this study is to determine HF prevalence in the Portuguese population. Using current standards, this manuscript aims to describe the methodology and research protocol applied. MethodsThe Portuguese Heart Failure Prevalence Observational Study (PORTHOS) is a large, three-stage, population-based, nationwide, cross-sectional study. Community-dwelling citizens aged 50 years and older will be randomly selected via stratified multistage sampling. Eligible participants will be invited to attend a screening visit at a mobile clinic for HF symptom assessment, anthropomorphic assessment, N-terminal pro-B-type natriuretic peptide (NT-proBNP) testing, one-lead electrocardiogram (ECG) and a sociodemographic and health-related quality of life questionnaire (EQ-5D). All subjects with NT-proBNP ≥125 pg/mL or with a prior history of HF will undergo a diagnostic confirmatory assessment at the mobile clinic composed of a 12-lead ECG, comprehensive echocardiography, HF questionnaire (KCCQ) and blood sampling. To validate the screening procedure, a control group will undergo the same diagnostic assessment. Echocardiography results will be centrally validated, and HF diagnosis will be established according to the European Society of Cardiology HF guidelines. A random subsample of patients with an equivocal HF with preserved ejection fraction diagnosis based on the application of the Heart Failure Association preserved ejection fraction diagnostic algorithm will be invited to undergo an exercise echocardiography. ConclusionsThrough the application of current standards, appropriate methodologies, and a strong research protocol, the PORTHOS study will determine the prevalence of HF in mainland Portugal and enable a comprehensive characterization of HF patients, leading to a better understanding of their clinical profile and health-related quality of life.

Trends in Serum Per- and Polyfluoroalkyl Substance (PFAS) Concentrations in Teenagers and Adults, 1999–2018 NHANES

Some types of per- and poly-fluoroalkyl substances (PFAS) have been banned over the last two decades, but millions of Americans continue to have exposure to the compounds through drinking water and consumer products. Therefore, understanding the changes in serum PFAS concentrations after their limited use is necessary to protect public health. In this study, we evaluated trends of serum PFAS compounds (PFOS, PFOA, PFHxS, PFDA, and PFNA) to determine their distribution among the United States general population. We analyzed serum concentrations of PFAS measured from random subsamples of the National Health and Nutrition Examination Survey (NHANES) participants. The study results demonstrated that demographic factors such as race/ethnicity, age, and sex may influence the levels of serum PFAS over time. Adults, males, Asians, Non-Hispanic Blacks, and Non-Hispanic Whites had high risks of exposure to the selected PFAS. Overall, serum PFAS levels declined continuously in the studied population from 1999 to 2018. Among the studied population, PFOS and PFDA were the most and least prevalent PFAS in blood serum, respectively. Serum levels of PFDA, PFOA, and PFHxS showed upward trends in at least one racial/ethnic group after 2016, which underscores the need for continuous biomonitoring of PFAS levels in humans and the environment.

The unseen casualties of the First World War: insights from a randomly selected military sample.

Studies of the morbidity burden of military personnel participating in the First World War (WWI) have tended to focus on specific outcomes (e.g., injuries). Therefore, we aimed for a more complete assessment. From a random sample of active war service-exposed New Zealand WWI veterans used in previously published work, we examined a random subsample of 200 personnel. Data on diagnoses, hospitalisations and outcomes were extracted from the online archival military files. These personnel experienced a very high morbidity burden with 94% having at least one new condition diagnosed during their military service (mean: 2.4 per individual; range: 0 to 8). The relative severity of these conditions was reflected by the high level of hospitalisation (89% at least once; mean: 1.8 hospitalisations for new conditions per individual) and 59% of personnel being deemed no longer fit for military service at some stage. More of the new diagnoses were for infectious diseases than for conflict-related injuries (117 vs 50 cases per 100 personnel). Respiratory conditions such as influenza, pneumonia and tuberculosis affected 33% of personnel, and 14% were diagnosed with sexually transmitted infections. Diseases reflecting hazardous environmental conditions were relatively common e.g., for dysentery/gastroenteritis in 12% and scabies in 5% of personnel. Diagnoses suggestive of post-traumatic stress disorder (PTSD) were present in 10% and chemical warfare injuries in 6%. The overall morbidity burden of this military force in WWI was very high, and much higher than the previous official estimates.

Socioeconomic status is negatively associated with immunosenescence but positively associated with inflammation among middle-aged women in Cebu, Philippines

BackgroundSocioeconomic status (SES) gradients in health are well-documented, and while biological pathways are incompletely understood, chronic inflammation and accelerated immune aging (immunosenescence) among lower SES individuals have been implicated. However, previous findings have come from samples in higher income countries, and it is unclear how generalizable they are to lower- and middle-income countries (LMIC) with different infectious exposures and where adiposity—an important contributor to chronic inflammation—might show different SES patterning. To address this gap, we explored associations between SES and inflammation and immunosenescence in a sample of women in Cebu, Philippines. MethodsData came from the mothers of the Cebu Longitudinal Health and Nutrition Survey birth cohort (mean age: 47.7, range: 35–69 years). SES was measured as a combination of annual household income, education level, and assets. Chronic inflammation was measured using C-reactive protein (CRP) in plasma samples from 1,834 women. Immunosenescence was measured by the abundance of exhausted CD8T (CD8 + CD28-CD45RA-) and naïve CD8T and CD4T cells, estimated from DNA methylation in whole blood in a random subsample of 1,028. Possible mediators included waist circumference and a collection of proxy measures of pathogen exposure. ResultsSES was negatively associated with the measures of immunosenescence, with slight evidence for mediation by a proxy measure for pathogen exposure from the household’s drinking water source. In contrast, SES was positively associated with CRP, which was explained by the positive association with waist circumference. ConclusionsSimilar to higher income populations, in Cebu there is an SES-gradient in pathogen exposures and immunosenescence. However, lifestyle changes occurring more rapidly among higher SES individuals is contributing to a positive association between SES and adiposity and inflammation. Our results suggest more studies are needed to clarify the relationship between SES and inflammation and immunosenescence across LMIC.

The Impact of Edema on MRI Radiomics for the Prediction of Lung Metastasis in Soft Tissue Sarcoma.

This study aimed to evaluate whether radiomic features extracted solely from the edema of soft tissue sarcomas (STS) could predict the occurrence of lung metastasis in comparison with features extracted solely from the tumoral mass. We retrospectively analyzed magnetic resonance imaging (MRI) scans of 32 STSs, including 14 with lung metastasis and 18 without. A segmentation of the tumor mass and edema was assessed for each MRI examination. A total of 107 radiomic features were extracted for each mass segmentation and 107 radiomic features for each edema segmentation. A two-step feature selection process was applied. Two predictive features for the development of lung metastasis were selected from the mass-related features, as well as two predictive features from the edema-related features. Two Random Forest models were created based on these selected features; 100 random subsampling runs were performed. Key performance metrics, including accuracy and area under the ROC curve (AUC), were calculated, and the resulting accuracies were compared. The model based on mass-related features achieved a median accuracy of 0.83 and a median AUC of 0.88, while the model based on edema-related features achieved a median accuracy of 0.75 and a median AUC of 0.79. A statistical analysis comparing the accuracies of the two models revealed no significant difference. Both models showed promise in predicting the occurrence of lung metastasis in soft tissue sarcomas. These findings suggest that radiomic analysis of edema features can provide valuable insights into the prediction of lung metastasis in soft tissue sarcomas.

The Gender Self-Report: A multidimensional gender characterization tool for gender-diverse and cisgender youth and adults.

Gender identity is a core component of human experience, critical to account for in broad health, development, psychosocial research, and clinical practice. Yet, the psychometric characterization of gender has been impeded due to challenges in modeling the myriad gender self-descriptors, statistical power limitations related to multigroup analyses, and equity-related concerns regarding the accessibility of complex gender terminology. Therefore, this initiative employed an iterative multi-community-driven process to develop the Gender Self-Report (GSR), a multidimensional gender characterization tool, accessible to youth and adults, nonautistic and autistic people, and gender-diverse and cisgender individuals. In Study 1, the GSR was administered to 1,654 individuals, sampled through seven diversified recruitments to be representative across age (10-77 years), gender and sexuality diversity (∼33% each gender diverse, cisgender sexual minority, cisgender heterosexual), and autism status (> 33% autistic). A random half-split subsample was subjected to exploratory factor analytics, followed by confirmatory analytics in the full sample. Two stable factors emerged: Nonbinary Gender Diversity and Female-Male Continuum (FMC). FMC was transformed to Binary Gender Diversity based on designated sex at birth to reduce collinearity with designated sex at birth. Differential item functioning by age and autism status was employed to reduce item-response bias. Factors were internally reliable. Study 2 demonstrated the construct, convergent, and ecological validity of GSR factors. Of the 30 hypothesized validation comparisons, 26 were confirmed. The GSR provides a community-developed gender advocacy tool with 30 self-report items that avoid complex gender-related "insider" language and characterize diverse populations across continuous multidimensional binary and nonbinary gender traits. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Never underestimate biodiversity: how undersampling affects Bray–Curtis similarity estimates and a possible countermeasure

The Bray–Curtis dissimilarity is widely used to calculate β diversity on abundance data. However, the effect of undersampling on this index has received limited attention and only few studies addressed this topic. The paper aimed to investigate the error introduced by undersampling and its correlation to the similarity of the complete datasets, proposing a possible countermeasure, which is based on the addition of dummy species. To evaluate the performance of this proposed approach, we applied a meta-analytic technique based on repeated and random subsamples of 16 datasets on published biological assemblage data. We estimated the effect of undersampling on the resulting similarities and we compared the results with the adjusted version of the index resulted from the addition of extra species, also called dummy species, to the original abundance dataset. Undersampling generally resulted in poor accuracy and led to underestimates of assemblage similarities. The addition of dummy species resulted in a decrease in the severity of underestimations. To reach an accuracy >80% in similarity, more than 300 individuals needed to be randomly sampled and the under – and over-estimation rates decreased consistently by the addition of dummy species. Additionally, we found that the more similar two assemblages were, the more likely similarities were underestimated and this tendency was more severe at low sample sizes. Our simulation indicated that datasets which contain more than 300 individuals provided reliable estimates of similarities and that the addition of one to three dummy species to the abundance matrices was a good choice to reduce underestimates and increase accuracy.

Faunal Diet of Adult Cane Toads, Rhinella marina, in the Urban Landscape of Southwest Florida.

We investigated the diet of cane toads (Rhinella marina) inhabiting urbanized areas in southwest Florida to provide high taxonomic resolution of prey items, contrast toad diets between sampling seasons and sexes, and assess this invasive species' ecological role in the urban landscape. A pest control agency collected cane toads from two golf course communities in Naples, Florida, USA during November-December 2018 (early dry season) and June-July 2019 (early wet season), and faunal stomach contents were quantified from a random subsample of 240 adult toads (30 males and 30 females from each community and season). Yellow-banded millipedes (Anadenobolus monilicornis), big-headed ants (Pheidole spp.), and hunting billbugs (Sphenophorus venatus vestitus) were the most frequently consumed prey items and had the highest total numbers and/or volume with corresponding highest indices of relative importance. There was considerable overlap in the seasonal prey importance values for each golf course community and little if any difference in the importance values between toad sexes in each community. Nonetheless, big-headed ants were the most important prey in both communities during the wet season, while yellow-banded millipedes were the most important dry season prey in one community and hunting billbugs the most important in the other. Despite limited spatiotemporal sampling effort, our results indicated that cane toad was consuming arthropod taxa considered pests in the urban ecosystem. Further studies are needed to investigate the potential effects of human activities and environmental variability on the cane toad diet and to determine whether cane toads act as a biological control for pest populations.

Substance use and misuse among college students: Results of an online survey from three neighboring cities of North India.

We estimated prevalence and severity of substance use in college students from three cities in North India and explored demographic correlates of substance use. This was a cross-sectional online survey. We used Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST). We contacted respondents through social groups. We performed analyses from the original sample, bootstrapped samples, and random subsamples. A total of 229 (58.3%) respondents reported any lifetime substance use. A third of substance-using respondents were female. Alcohol (54.7%), tobacco (40.2%), and cannabis (15%) use were most commonly reported. Prevalence estimates did not differ between original and subsample analyses. A significant proportion of respondents (alcohol 29.7% and amphetamines 66.7%) were at moderate risk level. Male gender, family history of substance use, and commerce stream correlated with substance use. There were positive correlations between tobacco and alcohol and licit and illicit substance use. The study highlights the need for a comprehensive college substance misuse prevention policy.

Exposure of the general French population to herbicides, pyrethroids, organophosphates, organochlorines, and carbamate pesticides in 2014-2016: Results from the Esteban study.

Esteban is a nationwide cross-sectional study conducted in France in 2014-2016, including 2503 adults aged 18-74 years old and 1104 children aged 6-17 years old, as part of the French Human Biomonitoring programme. The present paper describes the biological levels of five families of pesticides analysed on random sub-samples of 900 adults and 500 children for urine concentrations, and 759 adults and 255 children for serum concentrations, and the determinants of exposure. Organophosphates, carbamates and herbicides were measured in urine by UPLC-MS/MS; chlorophenols and pyrethroids were measured in urine by GC-MS/MS; specific organochlorines were measured in serum by GC-HRMS. Multivariate analyses were performed to identify the determinants of exposure using a generalized linear model. Pyrethroid metabolites were quantified in 99% of adults and children, with the exeption of F-PBA, which was quantified in 31% of adults and 27% of children, respectively. Carbamates and some specific organophosphates were barely or not quantified. DMTP was quantified in 82% of adults and 93% of children, and γ-HCH (lindane) was quantified in almost 50% of adults and children. Concentration levels of pesticide biomarkers were consistent with comparable international studies, except for β-HCH, DMTP, and the deltamethrin metabolite Br2CA, whose levels were sometimes higher in France. Household insecticide use and smoking were also associated with higher levels of pyrethroids. All pyrethroids concentration levels were below existing health-based HBM guidance values, HBM-GVsGenPop, except for 3-PBA, for which approximately 1% and 10% of children were above the lower and upper urine threshold values of 22μg/L and 6.4μg/L, respectively. Esteban provides a French nationwide description of 70 pesticide biomarkers for the first time in children. It also describes some pesticide biomarkers for the first time in adults, including glyphosate and AMPA. For the latter, urine concentration levels were overall higher in children than in adults. Our results highlight a possible beneficial impact of existing regulations on adult exposure to organochlorine and organophosphate pesticides between 2006 and 2016, as concentration levels decreased over this period.

Characterizing Twitter chatter about temporary alcohol abstinence during "Dry January".

With roots as a public health campaign in the United Kingdom, "Dry January" is a temporary alcohol abstinence initiative encouraging participants to abstain from alcohol use during the month of January. Dry January has become a cultural phenomenon, gaining increasing news media attention and social media engagement. Given the utility of capturing naturalistic discussions around health topics on social media, we examined Twitter chatter about Dry January and associated temporary abstinence experiences. Public tweets were collected containing the search terms "dry january" or "dryjanuary" posted between 15 December and 15 February across 3years (2020-2). A random subsample stratified by year (n = 3145) was pulled for manual content analysis by trained coders. Final codebook accounted for user sentiment toward Dry January, user account type, and themes related to Dry January participation. Engagement metadata (e.g. likes) were also collected. Though user sentiment was mixed, most tweets expressed positive or neutral sentiment toward Dry January (74.7%). Common themes included encouragement and support for Dry January participation (14.1%), experimentation with and promotion of nonalcoholic drinks (14.0%), and benefits derived from Dry January participation (10.4%). While there is promise in the movement to promote positive alcohol-related behavior change, increased efforts to deliver the campaign within a public health context are needed. Health communication campaigns designed to inform participants about evidence-based treatment and recovery support services proven to help people quit or cut down on their drinking are likely to maximize benefits.

Validity and reliability of the WHOQOL-BREF in a pregnant population

BackgroundPhysical end emotional changes during pregnancy may not only affect pregnant womens’ quality of life, but also how instruments assessing quality of life perform in such populations. To date, there is insufficient evidence on psychometric properties for both generic and condition-specific instruments measuring quality of life during pregnancy. The aim of this study was thus to examine the structural validity, internal consistency, and construct validity of the WHOQOL-BREF in a sample of pregnant women.MethodsA convenience sample of 1015 pregnant women in Sweden completed the WHOQOL-BREF online. We examined the psychometric properties of the instrument using principal component analysis (PCA), confirmatory factor analysis (CFA), Cronbach’s alpha, item-domain correlations, correlations with overall QOL and general health, and multiple linear regression with items on overall QOL and general health as outcomes.ResultsPrincipal Component Analysis in a random subsample (n = 502) supported a four-factor model, encompassing the domains physical, psychological, social and environmental quality of life, but with four of the items originally in the environmental domain relocated to the other domains. The proposed domain structure showed good fit in confirmatory factor analysis in the other random subsample (n = 513). The physical and psychological domains showed good internal consistency (Cronbach’s alpha = 0.885 and 0.826 respectively), while the social and environmental domains were weaker in this regard. All domains showed significant positive correlations with items on overall QOL and general health. The physical and psychological domains were the most evident predictors in the regression models.ConclusionsWe find the Swedish version of the WHOQOL-BREF to have good psychometric properties to be used in samples of pregnant women, and propose an alternative domain structure that might be even more useful for assessing quality of life during pregnancy. The physical and psychological domains showed good internal consistency and construct validity.

Antifa’s Political Violence on Twitter: a Grounded Theory Approach

This paper explores antifa activists’ use of doxing on Twitter against individuals perceived as alt-right militants. Following the principles of Grounded Theory, we collected 4690 tweets published by antifa users between September 2019 and September 2020 and analysed a random subsample of 1638. Results show that antifa users perceive alt-right activists as a serious threat to their worldview and seek to neutralise their activism even at the cost of making them social pariahs. To achieve that goal, antifa activists collect personal data on persons they suspect of being alt-right activists to “build a case” and then disseminate that information through different virtual social networks to the largest audience possible. The aim of doxing is to encourage other social actors to react and take actions that could be detrimental to the individual targeted. The article discusses practical and ethical implications of this kind of political-based harassment and suggests that future research on doxing could focus on antifa blogs and websites, which include sensitive information forbidden on Twitter.

An Ensemble Outlier Detection Method Based on Information Entropy-Weighted Subspaces for High-Dimensional Data.

Outlier detection is an important task in the field of data mining and a highly active area of research in machine learning. In industrial automation, datasets are often high-dimensional, meaning an effort to study all dimensions directly leads to data sparsity, thus causing outliers to be masked by noise effects in high-dimensional spaces. The "curse of dimensionality" phenomenon renders many conventional outlier detection methods ineffective. This paper proposes a new outlier detection algorithm called EOEH (Ensemble Outlier Detection Method Based on Information Entropy-Weighted Subspaces for High-Dimensional Data). First, random secondary subsampling is performed on the data, and detectors are run on various small-scale sub-samples to provide diverse detection results. Results are then aggregated to reduce the global variance and enhance the robustness of the algorithm. Subsequently, information entropy is utilized to construct a dimension-space weighting method that can discern the influential factors within different dimensional spaces. This method generates weighted subspaces and dimensions for data objects, reducing the impact of noise created by high-dimensional data and improving high-dimensional data detection performance. Finally, this study offers a design for a new high-precision local outlier factor (HPLOF) detector that amplifies the differentiation between normal and outlier data, thereby improving the detection performance of the algorithm. The feasibility of this algorithm is validated through experiments that used both simulated and UCI datasets. In comparison to popular outlier detection algorithms, our algorithm demonstrates a superior detection performance and runtime efficiency. Compared with the current popular, common algorithms, the EOEH algorithm improves the detection performance by 6% on average. In terms of running time for high-dimensional data, EOEH is 20% faster than the current popular algorithms.

Rapid Determination of Nutmeg Shell Content in Ground Nutmeg Using FT-NIR Spectroscopy and Machine Learning.

Nutmeg is a popular spice often used in ground form, which makes it highly susceptible to food fraud. Therefore, the aim of the present study was to detect adulteration of ground nutmeg with nutmeg shell via Fourier transform near-infrared (FT-NIR) spectroscopy. For this purpose, 36 authentic nutmeg samples and 10 nutmeg shell samples were analyzed pure and in mixtures with up to 50% shell content. The spectra plot as well as a principal component analysis showed a clear separation trend as a function of shell content. A support vector machine regression used for shell content prediction achieved an R2 of 0.944 in the range of 0-10%. The limit of detection of the prediction model was estimated to be 1.5% nutmeg shell. Based on random sub-sampling, the likelihood was found to be 2% that a pure nutmeg sample is predicted with a nutmeg shell content of >1%. The results confirm the suitability of FT-NIR spectroscopy for rapid detection and quantitation of the shell content in ground nutmeg.

Associations of plasma NfL, GFAP, and t-tau with cerebral small vessel disease and incident dementia: longitudinal data of the AGES-Reykjavik Study

We investigated the associations of plasma neurofilament light (NfL), glial fibrillary acidic protein (GFAP), and total tau (t-tau) with markers of cerebral small vessel disease (SVD) and with incident dementia. We also investigated whether associations of NfL, GFAP, and t-tau with incident dementia were explained by SVD. Data are from a random subsample (n = 1069) of the population-based AGES-Reykjavik Study who underwent brain MRI and in whom plasma NfL, GFAP, and t-tau were measured at baseline (76.1 ± 5.4 years/55.9% women/baseline 2002–2006/follow-up until 2015). A composite SVD burden score was calculated using white matter hyperintensity volume (WMHV), subcortical infarcts, cerebral microbleeds, and large perivascular spaces. Dementia was assessed in a 3-step process and adjudicated by specialists. Higher NfL was associated with a higher SVD burden score. Dementia occurred in 225 (21.0%) individuals. The SVD burden score significantly explained part of the association between NfL and incident dementia. WMHV mostly strongly contributed to the explained effect. GFAP was not associated with the SVD burden score, but was associated with WMHV, and WMHV significantly explained part of the association between GFAP and incident dementia. T-tau was associated with WMHV, but not with incident dementia. In conclusion, the marker most strongly related to SVD is plasma NfL, for which the association with WMHV appeared to explain part of its association with incident dementia. This study suggests that plasma NfL may reflect the contribution of co-morbid vascular disease to dementia. However, the magnitude of the explained effect was relatively small, and further research is required to investigate the clinical implications of this finding.