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Nevin Manimala Statistics

Comparative analyses of occupational injuries among temporary agency worker and direct contract workers: Findings from the Korea Health Panel 2009-2018

J Occup Health. 2022 Jan;64(1):e12326. doi: 10.1002/1348-9585.12326.

ABSTRACT

OBJECTIVES: Several studies have reported health or safety risk of temporary agency workers (TAW). Since most of the studies are just cross-sectional studies, we intended to identify the risk of occupational injury in TAW, using longitudinal study design.

METHODS: The Korea Health Panel 2009-2018 data were used in the study. For the statistical analysis of this study, we used a panel logit model to identify the risk of occupational injury in TAW compared to direct contract workers (DCW).

RESULTS: There was no significant difference in risk of occupational injury between TAW and DCW among the overall population (adjusted OR 0.920, 95% CI 0.600-1.411). However, there was a significant increase in occupational injury in women (adjusted OR 2.134, 95% CI 1.092-4.170) and the “19-34” age group (adjusted OR 2.744, 95% CI 1.103-6.825) of TAW.

CONCLUSIONS: This study provides evidence for vulnerable groups such as women and younger age groups in the relationship between TAW and occupational injury.

PMID:35338564 | DOI:10.1002/1348-9585.12326

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Nevin Manimala Statistics

Five decades of misunderstanding in the social Hymenoptera: a review and meta-analysis of Michener’s paradox

Biol Rev Camb Philos Soc. 2022 Mar 25. doi: 10.1111/brv.12854. Online ahead of print.

ABSTRACT

In a much-cited 1964 paper entitled “Reproductive efficiency in relation to colony size in hymenopterous societies,” Charles Michener investigated the correlation between a colony’s size and its reproductive efficiency – the ability of its adult females to produce reproductives, measured as per-capita output. Based on his analysis of published data from destructively sampled colonies in 18 species, he reported that in most of these species efficiency decreased with increasing colony size. His conclusion that efficiency is higher in smaller groups has since gained widespread acceptance. But it created a seeming paradox: how can natural selection maintain social behaviour when a female apparently enjoys her highest per-capita output by working alone? Here we treat Michener’s pattern as a hypothesis and perform the first large-scale test of its prediction across the eusocial Hymenoptera. Because data on actual output of reproductives were not available for most species, Michener used various proxies, such as nest size, numbers of brood, or amounts of stored food. We show that for each of Michener’s data sets the reported decline in per-capita productivity can be explained by factors other than decreasing efficiency, calling into question his conclusion that declining efficiency is the cause of the pattern. The most prominent cause of bias is the failure of the proxy to capture all forms of output in which the colony invests during the course of its ontogeny. Other biasing factors include seasonal effects and a variety of methodological flaws in the data sets he used. We then summarize the results of 215 data sets drawn from post-1964 studies of 80 species in 33 genera that better control for these factors. Of these, 163 data sets are included in two meta-analyses that statistically synthesize the available data on the relationship between colony size and efficiency, accounting for variable sample sizes and non-independence among the data sets. The overall effect, and those for most taxonomic subgroups, indicates no loss of efficiency with increasing colony size. Two exceptional taxa, the halictid bees and independent-founding paper wasps, show negative trends consistent with the Michener hypothesis in some species. We conclude that in most species, particularly those with large colony sizes, the hypothesis of decreasing efficiency with increasing colony size is not supported. Finally, we explore potential mechanisms through which the level of efficiency can decrease, be maintained, or even increase, as colonies increase in size.

PMID:35338566 | DOI:10.1111/brv.12854

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Nevin Manimala Statistics

Omnibus testing approach for gene-based gene-gene interaction

Stat Med. 2022 Mar 26. doi: 10.1002/sim.9389. Online ahead of print.

ABSTRACT

Genetic interaction is considered as one of the main heritable component of complex traits. With the emergence of genome-wide association studies (GWAS), a collection of statistical methods dedicated to the identification of interaction at the SNP level have been proposed. More recently, gene-based gene-gene interaction testing has emerged as an attractive alternative as they confer advantage in both statistical power and biological interpretation. Most of the gene-based interaction methods rely on a multidimensional modeling of the interaction, thus facing a lack of robustness against the huge space of interaction patterns. In this paper, we study a global testing approaches to address the issue of gene-based gene-gene interaction. Based on a logistic regression modeling framework, all SNP-SNP interaction tests are combined to produce a gene-level test for interaction. We propose an omnibus test that takes advantage of (1) the heterogeneity between existing global tests and (2) the complementarity between allele-based and genotype-based coding of SNPs. Through an extensive simulation study, it is demonstrated that the proposed omnibus test has the ability to detect with high power the most common interaction genetic models with one causal pair as well as more complex genetic models where more than one causal pair is involved. On the other hand, the flexibility of the proposed approach is shown to be robust and improves power compared to single global tests in replication studies. Furthermore, the application of our procedure to real datasets confirms the adaptability of our approach to replicate various gene-gene interactions.

PMID:35338506 | DOI:10.1002/sim.9389

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Nevin Manimala Statistics

Clustering High-dimensional data via feature selection

Biometrics. 2022 Mar 25. doi: 10.1111/biom.13665. Online ahead of print.

ABSTRACT

High-dimensional clustering analysis is a challenging problem in statistics and machine learning, with broad applications such as the analysis of microarray data and RNA-seq data. In this paper, we propose a new clustering procedure called Spectral Clustering with Feature Selection (SC-FS), where we first obtain an initial estimate of labels via spectral clustering, then select a small fraction of features with the largest R-squared with these labels, i.e., the proportion of variation explained by group labels, and conduct clustering again using selected features. Under mild conditions, we prove that the proposed method identifies all informative features with high probability and achieves minimax optimal clustering error rate for the sparse Gaussian mixture model. Applications of SC-FS to four real world data sets demonstrate its usefulness in clustering high-dimensional data. This article is protected by copyright. All rights reserved.

PMID:35338489 | DOI:10.1111/biom.13665

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Nevin Manimala Statistics

Changes in the prevalence and sociodemographic correlates of eating disorder symptoms from 2013 to 2020 among a large national sample of U.S. young adults: A repeated cross-sectional study

Int J Eat Disord. 2022 Mar 26. doi: 10.1002/eat.23709. Online ahead of print.

ABSTRACT

OBJECTIVE: The present study aimed to: (1) identify recent temporal changes in the prevalence of different cognitive and behavioral eating disorder (ED) symptoms, current probable EDs, lifetime ED diagnoses, and mental healthcare use among college students across the United States; (2) determine whether established disparities in ED prevalence and receiving mental healthcare have widened or narrowed over time for marginalized groups within this population.

METHOD: Participants included a large national sample of U.S. college students (N = 286,720) who completed the repeated cross-sectional Healthy Minds Study from 2013 to 2020. Descriptive statistics and polynomial regressions quantified time-trends in participants’ ED symptoms and past 12-month mental healthcare. Moderated regressions examined temporal changes in ED symptoms and mental healthcare based on sociodemographic characteristics.

RESULTS: Individuals’ engagement in different cognitive and behavioral ED symptoms, and likelihoods of exhibiting current probable EDs, reporting lifetime ED diagnoses, and (for individuals with current probable EDs) receiving therapy or counseling in the past 12-months exhibited nonlinear increases from 2013 to 2020. Further, the prevalence of current and lifetime ED symptoms and (for symptomatic individuals) past 12-month mental healthcare differed over time for individuals with different BMIs and gender, sexual, and racial/ethnic identities (but not ages). In particular, individuals with higher BMIs and those who identified as male, bisexual, and gay, lesbian, or queer exhibited increasing ED pathology over time.

DISCUSSION: These findings provide important information on groups of U.S. college students that have experienced increasing burden of ED symptoms and may help guide ED prevention, treatment, and research priorities.

PUBLIC SIGNIFICANCE: Recent temporal changes in the prevalence of eating disorder (ED) symptoms and mental healthcare were examined in a national sample of U.S. young adults. Non-linear increases in ED symptoms and mental healthcare were identified among U.S. young adults overall from 2013 to 2020. U.S. young adults with higher BMIs, males, bisexual, and gay, lesbian, or queer individuals exhibited increasing ED burden over time.

PMID:35338504 | DOI:10.1002/eat.23709

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Nevin Manimala Statistics

Individual differences in brain structure and self-reported empathy in children

Cogn Affect Behav Neurosci. 2022 Mar 25. doi: 10.3758/s13415-022-00993-2. Online ahead of print.

ABSTRACT

Empathy refers to the understanding and sharing of others’ emotions and comprises cognitive and affective components. Empathy is important for social functioning, and alterations in empathy have been demonstrated in many developmental or psychiatric disorders. While several studies have examined associations between empathy and brain structure in adults, few have investigated this relationship in children. Investigating associations between empathy and brain structure during childhood will help us to develop a deeper understanding of the neural correlates of empathy across the lifespan. A total of 125 children (66 females, mean age 10 years) underwent magnetic resonance imaging brain scans. Grey matter volume and cortical thickness from structural images were examined using the Computational Anatomy Toolbox (CAT12) within Statistical Parametric Mapping (SPM12) software. Children completed questionnaire measures of empathy (cognitive empathy, affective empathy: affective sharing, empathic concern, and empathic distress). In hypothesised region of interest analyses, individual differences in affective and cognitive empathy were related to grey matter volume in the insula and the precuneus. Although these relationships were of similar strength to those found in previous research, they did not survive correction for the total number of models computed. While no significant findings were detected between grey matter volume and empathy in exploratory whole-brain analysis, associations were found between cortical thickness and empathic concern in the right precentral gyrus. This study provides preliminary evidence that individual differences in self-reported empathy in children may be related to aspects of brain structure. Findings highlight the need for more research investigating the neurobiological correlates of empathy in children.

PMID:35338471 | DOI:10.3758/s13415-022-00993-2

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Nevin Manimala Statistics

The environmental consequences of foreign aid and key economic indicators: the Sino-Africa perspective

Environ Sci Pollut Res Int. 2022 Mar 25. doi: 10.1007/s11356-021-16880-1. Online ahead of print.

ABSTRACT

The study differs substantially from earlier studies, by probing the environmental consequences of foreign aid and selected key economic indicators with a special focus on Sino-Africa. The study focused on China and its top foreign aid recipients in Africa in the last decade. This paper utilizes the Dynamic Augmented Mean Group Estimator (AMG), a robust and recent econometric approach to provide better statistical inferences; crucial for policy formulation and future reforms on foreign aid, trade, energy, pollutions, and economic growth of economies. The findings of the study revealed the China’s Foreign aid oriented towards infrastructure has varying impacts on the economic growth and the environment of most recipient African Countries. The findings revealed the incidence of foreign aid ameliorating pollution of the countries: Nigeria and Morocco under strong domestic institutions. The study is of key relevance for policymakers and stakeholders as it explicates the key pillars, policies, and guidelines needed for foreign aid, trade, economic growth, and related internal reforms for mitigating resulting environmental pollution across a wider international context.

PMID:35338460 | DOI:10.1007/s11356-021-16880-1

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Nevin Manimala Statistics

Is there a correlation between dental and cervical vertebrae maturation stages in growing subjects? A systematic review with meta-analysis

Clin Oral Investig. 2022 Mar 26. doi: 10.1007/s00784-022-04456-3. Online ahead of print.

ABSTRACT

OBJECTIVE: To assess the evidence on the relationship between dental and cervical vertebrae maturation.

MATERIALS AND METHODS: Searches were performed (up to December 2021) in seven databases, as well as in gray literature. Studies that included growing subjects, which evaluated the correlation between the stages of tooth formation and the maturation of cervical vertebrae, were eligible. The methodological quality of the selected reports was assessed using the JBI checklist for cross-sectional studies. Random-effects meta-analyses were implemented to calculate the pooled correlation coefficients between the maturation stages of cervical vertebrae and each tooth type. The GRADE approach was followed to assess the certainty of evidence.

RESULTS: Seventy-seven studies were selected. Most of them had limitations related to sampling and reliability of the methods to evaluate maturation. The syntheses evidenced positive correlations between the maturation of cervical vertebrae and the formation/calcification stages of the following lower teeth: canine (n = 7318; r = 0.692; 95% CI: 0.656-0.724), first premolar (n = 6194; r = 0.689; 95% CI: 0.649-0.725), second premolar (n = 6194; r = 0.695; 95% CI: 0.659-0.729), and second molar (n = 7905; r = 0.698; 95% CI: 0.652-0.739). All estimates were affected by the risk of bias and the presence of unexplained statistical heterogeneity.

CONCLUSIONS: The evidence points to an apparent positive correlation between dental and cervical vertebrae maturation. These results need to be carefully evaluated as the body of evidence is of very low quality.

CLINICAL RELEVANCE: Dental maturation might be a potential indicator of skeletal craniofacial growth status. A routine dental x-ray could be sufficient, reducing radiation exposure by requesting additional radiographs.

PMID:35338422 | DOI:10.1007/s00784-022-04456-3

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Nevin Manimala Statistics

White matter alterations in heart-kidney imbalance insomnia and Jiao-Tai-Wan treatment: A diffusion-tensor imaging study

Brain Imaging Behav. 2022 Mar 25. doi: 10.1007/s11682-022-00653-6. Online ahead of print.

ABSTRACT

Previous studies have reported changes in white matter microstructures in patients with insomnia. However, few neuroimaging studies have focused specifically on white matter tracts in insomnia patients after having received treatment. In this prospective study, diffusion-tensor imaging was used in two samples of heart-kidney imbalance insomnia patients who were treated with placebo or Jiao-Tai-Wan, a traditional Chinese medicine commonly used to treat heart-kidney imbalance insomnia, to assess the changes in white matter tracts. Tract-based spatial statistical analyses were first applied to compare the changes in mean diffusivity and fractional anisotropy of white matter between 75 heart-kidney imbalance insomnia patients and 41 healthy control participants. In subsequent randomized, double-blind, placebo-controlled trials, comparisons of mean diffusivity and fractional anisotropy were also performed in 24 heart-kidney imbalance insomnia patients (8 males; 16 females; 42.5 ± 10.4 years) with Jiao-Tai-Wan and 26 heart-kidney imbalance insomnia patients (11 males; 15 females; 39.7 ± 9.4 years) with a placebo, with age and sex as covariates. Fractional anisotropy values in left corticospinal tract were increased in heart-kidney imbalance insomnia patients. Heart-kidney imbalance insomnia patients showed lower mean diffusivity and fractional anisotropy values of several white matter tracts than healthy control participants, such as the bilateral anterior limb of internal capsule, bilateral superior longitudinal fasciculus and bilateral posterior corona radiata. After being treated with Jiao-Tai-Wan, heart-kidney imbalance insomnia patients showed a trend towards reduced fractional anisotropy values in the left corticospinal tract. Jiao-Tai-Wan may improve the sleep quality by reversing the structural changes of the left corticospinal tract caused by heart-kidney imbalance insomnia.

PMID:35338430 | DOI:10.1007/s11682-022-00653-6

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Nevin Manimala Statistics

Management of white spot lesions induced during orthodontic treatment with multibracket appliance: a national-based survey

Clin Oral Investig. 2022 Mar 25. doi: 10.1007/s00784-022-04454-5. Online ahead of print.

ABSTRACT

OBJECTIVES: The study aimed to survey current strategies against enamel demineralization during multibracket therapy (MBT) and guide a prevention concept based on existing scientific evidence.

MATERIALS AND METHODS: The survey comprised questions on the prevention and management of white spot lesions (WSL). The questionnaire was sent via email to orthodontists working in practices and universities throughout Germany. The analysis involved descriptive statistics using the chi-square test (p < 0.05).

RESULTS: A prevention protocol was used before MBT by 80.6% of the participants. Less than a quarter of the participants regularly applied topical fluoride (gel or varnish) during MBT. According to the respondents’ assessment, the prevalence of WSL during MBT is 11.6%, mainly observed in 12- to 15-year-old male patients. Orthodontists graduating after 2000 tended to recommend and apply fluoride-containing materials more often than their senior colleagues (p = 0.039). Participants from private practices applied fluoride varnish or gel more frequently than those from university clinics (p = 0.013). Fluoridation was the most common (70.7%) treatment for WSL after MBT, followed by resin infiltration (21.2%). The majority (80.9%) of the participants favor a guideline for preventing WSL.

CONCLUSIONS: WSL prevention during MBT is challenging. Males in puberty are predominantly affected. Younger orthodontists are more concerned about the prevention of WSL during MBT.

CLINICAL RELEVANCE: The non-negligible prevalence of individuals with WSL emphasizes the need for dental education and health care reform. This would help to implement standardized procedures and establish innovative applications.

PMID:35338421 | DOI:10.1007/s00784-022-04454-5