Categories
Nevin Manimala Statistics

A Simple Configural Approach for Testing Person-Oriented Mediation Hypotheses

Integr Psychol Behav Sci. 2021 Feb 25. doi: 10.1007/s12124-020-09598-1. Online ahead of print.

ABSTRACT

Statistical methods to test hypotheses about direct and indirect effects from a person-oriented research perspective are scarce. For categorical variables, previously suggested approaches use configural frequency analysis (CFA) to detect extreme patterns (CFA Types/Antitypes) that are responsible for the observed direct and indirect effects. Existing methods rest on complex (log-linear) model comparison strategies and may perform poorly with respect to Type I error protection and statistical power. We, therefore, propose a simplified configural approach to answer the question “What carries a mediation process?” This simplified approach is based on two log-linear models that are needed to estimate (variable-oriented) direct and indirect effects. The first model identifies extreme patterns for the predictor-mediator path, the second model searches for extreme cells in the mediator-outcome path. Joint significance testing can be used to test the presence of mediation. Definitions of Mediation Types/Antitypes are given based on possible Type/Antitype patterns for the binary simple mediation model. In two Monte-Carlo simulation experiments, we evaluate the performance of the simplified approach in a homogenous population (i.e., where all individuals develop homogenously along a variable-oriented mediation mechanism) and a heterogenous population (i.e., where specific configurations, instead of a variable-oriented effect, drive the mediation process). Results suggest that the presented approach performs acceptably with respect to Type I error protection and statistical power. In general, larger sample sizes are preferable to reliably detect mediation-generating configurations. An empirical example is given for illustrative purposes and extensions and limitations of the proposed method are discussed.

PMID:33634410 | DOI:10.1007/s12124-020-09598-1

Categories
Nevin Manimala Statistics

Characterization of Oral Bacterial Composition of Adult Smokeless Tobacco Users from Healthy Indians Using 16S rDNA Analysis

Microb Ecol. 2021 Feb 26. doi: 10.1007/s00248-021-01711-0. Online ahead of print.

ABSTRACT

The present investigation is aiming to report the oral bacterial composition of smokeless tobacco (SLT) users and to determine the influence of SLT products on the healthy Indian population. With the aid of the V3 hypervariable region of the 16S rRNA gene, a total of 8,080,889 high-quality reads were clustered into 15 phyla and 180 genera in the oral cavity of the SLT users. Comparative analysis revealed a more diverse microbiome where two phyla and sixteen genera were significantly different among the SLT users as compared to the control group (p-value < 0.05). The prevalence of Fusobacteria-, Porphyromonas-, Desulfobulbus-, Enterococcus-, and Parvimonas-like genera among SLT users indicates altered bacterial communities among SLT users. Besides, the depletion of health-compatible bacteria such as Lactobacillus and Haemophilus also suggests poor oral health. Here, the majority of the altered genera belong to Gram-negative anaerobes that have been reported for assisting biofilm formation that leads in the progression of several oral diseases. The PICRUSt analysis further supports the hypothesis where a significant increase in the count of the genes involved in the metabolism of nitrogen, amino acids, and nicotinate/nicotinamide was observed among tobacco chewers. Moreover, this study has a high significance in Indian prospects where the SLT consumers are prevalent but we are deficient in information on their oral microbiome.

PMID:33634334 | DOI:10.1007/s00248-021-01711-0

Categories
Nevin Manimala Statistics

The contribution of individual differences in statistical learning to reading and spelling performance in children with and without dyslexia

Dyslexia. 2021 Feb 25. doi: 10.1002/dys.1678. Online ahead of print.

ABSTRACT

Using an individual differences approach in children with and without dyslexia, this study investigated the hypothesized relationship between statistical learning ability and literacy (reading and spelling) skills. We examined the clinical relevance of statistical learning (serial reaction time and visual statistical learning tasks) by controlling for potential confounds at the participant level (e.g., non-verbal reasoning, attention and phonological skills including rapid automatized naming and phonological short-term memory). A 100 Dutch-speaking 8- to 11-year-old children with and without dyslexia participated (50 per group), see also van Witteloostuijn et al. (2019) for a study with the same participants. No evidence of a relationship between statistical learning and literacy skills is found above and beyond participant-level variables. Suggestions from the literature that the link between statistical learning and literacy attainment, and therefore its clinical relevance, might be small and strongly influenced by methodological differences between studies are not contradicted by our findings.

PMID:33631835 | DOI:10.1002/dys.1678

Categories
Nevin Manimala Statistics

Outcomes for the first wave of hospitalised patients with COVID-19 in the South Australian context: a retrospective audit

Intern Med J. 2021 Feb;51(2):189-198. doi: 10.1111/imj.15106.

ABSTRACT

BACKGROUND: The first case of corona virus disease (COVID-19) was detected in South Australia on 1 February 2020. The Royal Adelaide Hospital (RAH) is the state’s designated quarantine hospital.

AIM: To determine the characteristics, outcomes and predictors of outcomes for hospitalised patients with coronavirus disease (COVID-19) within the RAH.

METHODS: We performed a retrospective audit of 103 patients diagnosed with COVID-19 who were discharged from the RAH between 14 February and 21 May 2020. We collected demographic, clinical and laboratory data through an audit of electronic medical records. The main outcome measures were: (i) the need for oxygen supplementation; (ii) need for intensive care unit (ICU) care; and (iii) death in hospital.

RESULTS: The median age of patients was 60 years (range 19-85). A total of 55 (53%) patients was male. All patients were independent at baseline; 37 (36%) patients suffered from hypertension. Cardiovascular disease, respiratory disease and diabetes were present in fewer than 19 (18%) patients. Obesity was present in 24 (23%) patients; 39 (38%) patients required supplemental oxygen, 18 (17%) required ICU care and 4 (4%) patients died. Older patients were significantly more at risk of oxygen requirement (median 68 vs 57.5 years, P < 0.01), ICU admission (median 66.5 vs 60 years, P = 0.04) and death (median 74.5 vs 60 years, P = 0.02). We did not find a statistically significant association between gender, body mass index and poor outcomes. Lactate dehydrogenase (LDH) was the only parameter at admission associated with oxygen requirement, ICU care and death. Peak LDH, aspartate aminotransferase, alanine aminotransferase, C-reactive protein and neutrophil lymphocyte ratio were significantly associated with oxygen requirement, ICU admission and death (P < 0.05 for all of the above laboratory markers).

CONCLUSIONS: Although our sample size was small, we found that certain comorbidities and laboratory values were associated with poor outcomes. This occurred in a setting where care was not influenced by limited hospital and intensive care beds.

PMID:33631864 | DOI:10.1111/imj.15106

Categories
Nevin Manimala Statistics

Using Disposable Membrane Cell Collector to Enrich Lung Adenocarcinoma Cells in Bloody Pleural Effusion for Anaplastic Lymphoma Kinase Fusion Gene Detection

Acta Cytol. 2021 Feb 25:1-7. doi: 10.1159/000512868. Online ahead of print.

ABSTRACT

PURPOSE: For anaplastic lymphoma kinase (ALK) gene detection, the centrifugal sedimentation method (CSM) and cell block method (CBM) are commonly used to process samples of bloody pleural effusions (BPEs). However, in practice, the impurity content in the processed samples often affects the results and even leads to the detection failure. The purpose of this study was to establish a cell enrichment method (CEM) by using a disposable membrane cell collector to remove blood and inflammatory cells and enrich lung adenocarcinoma cells in BPE for more efficient RNA extraction and ALK gene detection.

MATERIALS AND METHODS: CEM proposed in this study and the traditional CSM and CBM were used to treat BPE samples collected from 37 lung adenocarcinoma patients. A DeNovix DS-11 ultraviolet spectrophotometer was used to measure the concentration and purity of extracted RNA. Amplification refractory mutation systems (ARMS) and ABI 7500 fluorescence qPCR were used to detect ALK gene. Through statistical analysis, the CEM was compared with the CSM and CBM in RNA concentration, purity, and ALK gene detection results.

RESULTS: The concentration of RNA extracted by using the CEM was significantly higher than that extracted by using the CBM and CSM (p < 0.001). The purity of RNA extracted by using the CEM was significantly higher than that by the other 2 methods (p = 0.011, p = 0.005). ALK gene testing with PCR was successful in all the samples using the CEM, but 2 cases by the CSM and 1 case by the CBM failed.

CONCLUSIONS: Using the disposable membrane cell collector to process BPE of lung adenocarcinoma patients for RNA extraction and ALK gene detection is more effective and successful compared with the traditional methods, and it is suggested to be further applied and popularized in clinical practice.

PMID:33631757 | DOI:10.1159/000512868

Categories
Nevin Manimala Statistics

Would Women With Solid Organ Transplant Qualify for Triennial Cervical Cancer Screening as Recommended by the American College of Obstetricians and Gynecologists in 2016 and American Society for Colposcopy and Cervical Pathology in 2019?

J Low Genit Tract Dis. 2021 Feb 25. doi: 10.1097/LGT.0000000000000588. Online ahead of print.

ABSTRACT

OBJECTIVE: The aim of the study was to assess the applicability and safety of cervical cancer screening guidelines recommended by the American College of Obstetricians and Gynecologists (2016) and American Society for Colposcopy and Cervical Pathology (2019) for women with solid organ transplants (SOTs).

MATERIALS AND METHODS: We analyzed data previously abstracted through December 2015 for 971 women (18-60 y) who received their first SOT at Mayo Clinic (Rochester, MN) from January 17, 1995, through December 31, 2011. Inclusion criteria were initial benign findings on cervical cytology after SOT and at least 1 subsequent cytologic screening.

RESULTS: Of 415 women whose initial cytologic findings were benign, 310 met inclusion criteria. The cumulative incidence of abnormal cervical cytology among these 310 women was 4.3% (95% CI = 1.9%-6.7%) by 30 months and 11.2% (95% CI = 7.1%-15.4%) by 60 months after their initial benign results. Considering all women with SOT, 68.4% (284/415) had no documented abnormal cytologic findings within 60 months (26 had abnormality; 284 no abnormality; and 105 not assessed). In women with negative tests for human papillomavirus, high-grade squamous intraepithelial lesions were not documented on cytology with variable duration of follow-up. No cervical squamous cell carcinoma was identified.

CONCLUSIONS: Of women with initial benign cervical cytology after SOT, more than two thirds would have been eligible for extended-interval screening. Further study is needed, particularly regarding the role of high-risk human papillomavirus testing.

PMID:33631778 | DOI:10.1097/LGT.0000000000000588

Categories
Nevin Manimala Statistics

Electrophysiological correlates of conventional metaphor, irony, and literal language processing – An event-related potentials and eLORETA study

Brain Lang. 2021 Feb 22;215:104930. doi: 10.1016/j.bandl.2021.104930. Online ahead of print.

ABSTRACT

Conventional metaphor, irony, and literal language processing were compared. Thirty right-handed participants (21-34 years) performed a sequential-statement ERP-paradigm. A left-frontal Late Anterior Negative Slow Wave (LANSW, 450-1000 ms) was significantly greater for metaphors and by visual tendency greater for irony, compared to literal statements. A centroparietal N400 (300-450 ms) and a centroparietal right-dominant “Late N400” (450-600 ms) were by statistical and visual tendency greater for metaphors. Left PCC and left lingual gyrus activity was significantly higher in metaphors compared to literal statements (eLORETA; 450-1000 ms). A statistical trend indicated higher parahippocampal gyrus activity in metaphors and ironies. N400 results are discussed considering changing processing techniques and a renewed semantic conflict. The Late N400 was associated with the construct of “associativeness”. The LANSW was related to metaphorical mapping, frame-shifting processes, integration of meanings, and memory processes. eLORETA results were discussed considering metaphorical mapping, creation of mental images, conventionality, valence, memory processes, and divergent thinking.

PMID:33631658 | DOI:10.1016/j.bandl.2021.104930

Categories
Nevin Manimala Statistics

Stair ascent comparison of lower limb kinematics with differing time normalization techniques

J Biomech. 2021 Feb 12;119:110316. doi: 10.1016/j.jbiomech.2021.110316. Online ahead of print.

ABSTRACT

Understanding gait differences in context of group differences is dependent on statistical testing methods and time normalization techniques (TN). The method induces a relationship of both with one another. As to our knowledge, there has been no investigation into their relation so far. To show empirically what effects may be of importance, we use SPM with linear time interpolation (LI) and Dynamic Time Warping (DTW) separately for data of a study on stair ascent kinematics between two groups. There is a slight difference in statistical significance for the comparison of LI and DTW. LI-uniquely significant time highlight differences due to in-group time-variations, whereas DTW-uniqueness is tied to qualitative differences of homogeneous events. The comparison of stair ascent kinematics with DTW shows more pronounced evidence for backlift-like strategies for the older group, although trunk angles are kept more extended as to ensure stabilty. Thus, the difference in SPM from TN is slight but important, if there is need to mirror said effects methodically.

PMID:33631663 | DOI:10.1016/j.jbiomech.2021.110316

Categories
Nevin Manimala Statistics

Impact of social networks on the choice of place of delivery among ethnic women in Bangladesh

Sex Reprod Healthc. 2020 Dec 23;28:100588. doi: 10.1016/j.srhc.2020.100588. Online ahead of print.

ABSTRACT

OBJECTIVES: This study aims at exploring the present situation of the delivery place and the impact of social networks on the choice of delivery place among the ethnic women in Bangladesh.

METHODS: Data were collected through face to face interviews using a structured questionnaire from a sample of 205 married ethnic – Garo and Mandai – women in Madhupur Upazilla of Tangail district. A stepwise binary logistic regression analysis is run to explain the impact of social networks on the choice of delivery place (the place where the women actually did deliver a baby) of ethnic women in Bangladesh.

RESULTS: Descriptive statistics show that of the total deliveries 37.7% among Garo- and 13% among Mandai women take place in institutions (hospitals and clinics). The regression model reveals that next to ethnicity and husband’s occupation, network size has a significant positive relationship, while reproductive health-related constraints have a significant negative relationship with the choice of delivery place of ethnic women. Based on these, this study suggests that if the social networks of ethnic women increase, the probability of their institutional delivery may increase.

CONCLUSION: The personal social networks of ethnic women may motivate them on their choice of institutional delivery in Bangladesh. This finding may contribute to the development of pathways to stimulate ethnic women’s reproductive health behaviour in the developing countries context.

PMID:33631702 | DOI:10.1016/j.srhc.2020.100588

Categories
Nevin Manimala Statistics

Spotlight on Cardiovascular Scoring Systems in Covid-19: Severity Correlations in Real-world Setting

Curr Probl Cardiol. 2021 Feb 15;46(5):100819. doi: 10.1016/j.cpcardiol.2021.100819. Online ahead of print.

ABSTRACT

OBJECTIVES AND METHODS: the current understanding of the interplay between cardiovascular (CV) risk and Covid-19 is grossly inadequate. CV risk-prediction models are used to identify and treat high risk populations and to communicate risk effectively. These tools are unexplored in Covid-19. The main objective is to evaluate the association between CV scoring systems and chest X ray (CXR) examination (in terms of severity of lung involvement) in 50 Italian Covid-19 patients. Results only the Framingham Risk Score (FRS) was applicable to all patients. The Atherosclerotic Cardiovascular Disease Score (ASCVD) was applicable to half. 62% of patients were classified as high risk according to FRS and 41% according to ASCVD. Patients who died had all a higher FRS compared to survivors. They were all hypertensive. FRS≥30 patients had a 9.7 higher probability of dying compared to patients with a lower FRS. We found a strong correlation between CXR severity and FRS and ASCVD (P < 0.001). High CV risk patients had consolidations more frequently. CXR severity was significantly associated with hypertension and diabetes. 71% of hypertensive patients’ CXR and 88% of diabetic patients’ CXR had consolidations. Patients with diabetes or hypertension had 8 times greater risk of having consolidations.

CONCLUSIONS: High CV risk correlates with more severe CXR pattern and death. Diabetes and hypertension are associated with more severe CXR. FRS offers more predictive utility and fits best to our cohort. These findings may have implications for clinical practice and for the identification of high-risk groups to be targeted for the vaccine precedence.

PMID:33631706 | DOI:10.1016/j.cpcardiol.2021.100819