Χ2 Statistic Research Articles

Toxicity Spectrum of Anti-GD2 Immunotherapy: A Real-World Study Leveraging the US Food and Drug Administration Adverse Event Reporting System.

Anti-disialoganglioside (anti-GD2) monoclonal antibodies are effective immunotherapeutic drugs for treating neuroblastoma, yet their toxicity spectrum is unclear. This study aimed to assess the toxicity profiles of three anti-GD2 monoclonal antibodies (dinutuximab, dinutuximab β, and naxitamab) in clinical applications by mining and evaluating the adverse drug reaction (ADR) signals from the US Food and Drug Administration Adverse Event Reporting System. Data in the US Food and Drug Administration Adverse Event Reporting System from the time anti-GD2 monoclonal antibodies became available in the market to the first quarter of 2023 were searched. The signals of anti-GD2 monoclonal antibody-associated ADRs were quantified using four types of algorithms, including the reporting odds ratio, the proportional reporting ratio, the combination of the proportional reporting ratio and χ2 statistic method used by the UK Medicines and Healthcare Products Regulatory Agency, and the Bayesian confidence propagation neural network. The ADRs were categorized by System Organ Class based on the Medical Dictionary for Regulatory Activities, and were sorted according to the frequency and signal strength of ADRs. A total of 370 adverse drug event reports with anti-GD2 monoclonal antibodies listed as the 'primary suspected drugs' were identified, with 116 ADR signals detected, of which 22 were not in the drug labels. Among the adverse drug event reports, 276 reports concerned dinutuximab/dinutuximab β as primary suspected drugs with 90 ADR signals, involving 19 System Organ Classes, of which 21 signals were not in the label; 94 adverse drug event reports concerned naxitamab as the primary suspected drug with 26 ADR signals, involving 11 System Organ Classes, of which one was not in the label. For dinutuximab/dinutuximab β-related ADRs, the top five most frequent were "fever", "abdominal pain", "elevated aspartate aminotransferase (AST)", "elevated alanine aminotransferase (ALT)" and "hypotension"; the top five most intensive signals were "hypoalbuminemia", "elevated AST", "capillary leakage syndrome", "hypoxia" and "elevated ALT". For naxitamab-related ADRs, the top five most frequent were "hypotension", "pain", "urticarial", "hypertension" and "rash"; the top five most intensive signals were "hypotension", "urticaria", "hypoxemia", "bronchospasm" and "hypertension". Involved System Organ Classes included "investigations" and "respiratory, thoracic and mediastinal disorders" containing the most types of ADR signals in dinutuximab/dintuximab β-related ADRs and naxitamab-related ADRs, respectively. Our study comprehensively analyzed the toxicity profiles of anti-GD2 monoclonal antibodies and provides an important reference for clinical monitoring and ADR identification of these drugs.

A Cross-sectional Study on Caffeine Dependency by Drinking Tea and Coffee Among Bangladeshi Students

Too much caffeine consumption might cause physical and mental dependency on the consumer. This study examined the socio-demographic factors, knowledge, behavior, and perception of Bangladeshi students about caffeine which is based on drinking tea and coffee. This questionnaire-based study included 1020 respondents from primary level to postgraduate level students. The analysis utilized frequencies, means, percentages, Pearson's chi-square (χ2) statistic and Spearman's rank correlation coefficients. Pearson's chi-square (χ2) statistic test was performed to determine the significance at 5% with a p-value < 0.05. Most of the students (94.8%) consume tea or coffee regularly, and 66.1% drink it daily. A total of 87.5% of students knew that tea and coffee have caffeine. Nearly two-thirds (67.1%) of the students were dependent on tea and coffee, and 35.9% experienced psycho-physiological alterations after a day without drinking those items. About 38% of students noticed side effects after consumption of tea or coffee multiple times in a day. This study also reveals that gender did not alter the knowledge or drinking behavior of tea and coffee. Tea and coffee drinking patterns were not significantly dependent upon the participants’ educational qualifications. Dhaka Univ. J. Pharm. Sci. 22(2): 202-212, 2023 (December)

Molecular prevalence of Coxiella burnetii in cheese samples: Systematic review and meta-analysis.

Cheese is a popular dairy product consumed worldwide, and it has been implicated as a source of Coxiella burnetii infections. The present study aimed to describe the molecular prevalence and source analysis of C. burnetii in cheese samples. A systematic literature search was conducted using the Medline/PubMed, Science Direct, Web of Science, Scopus, and Google Scholar databases to identify studies reporting the molecular prevalence of C. burnetii in cheese samples. The pooled prevalence of C. burnetii in cheese samples was estimated using a random-effects model. A meta-analysis was conducted using the mean and standard deviation values obtained from 13 original studies. The overall molecular prevalence of C. burnetii in cheese was estimated to be 25.2% (95% confidence interval [CI]: 13.1%-39.7%). The I2 value of 96.3% (CI95% 94.9-97.3) suggested high heterogeneity, with a τ2 of 0.642 (CI95% -0.141 to 0.881), and an χ2 statistic of 323.77 (p<0.0001). In conclusion, our meta-analysis provides a thorough assessment of the molecular prevalence and source analysis of C. burnetii in cheese samples.

Nutrition Environment Gaps and Distribution Challenges in Rural Food Pantries During the COVID-19 Pandemic: A Mixed-Methods Study

BackgroundFood insecurity disproportionately affects low-income, racially marginalized, and rural communities. The COVID-19 pandemic led to higher demand for emergency food distribution, potentially impacting food pantry operations and services. Limited research exists assessing consumer nutrition environments of pantries in rural regions. ObjectivesTo assess the consumer nutrition environment of rural food pantries and report challenges and adaptations encountered during the pandemic. DesignA mixed-methods, cross-sectional survey. Participants/SettingNineteen food pantry representatives from California’s San Joaquin Valley were surveyed between August 2020 and June 2021. Representatives were eligible if their pantry served the general population and was open at least once a week. Nine were church-based pantries, and 10 were from other settings. Main outcome measuresThe Nutrition Environment Food Pantry Assessment Tool (NEFPAT) measured the nutrition food environment and scored pantries as bronze (0–15), silver (16–31), or gold (32–47) categories. Eleven items were developed to explore pandemic-related challenges. Statistical analyses performedIndependent χ2 tests assessed the relationship between the organization type and NEFPAT scores and food supply sources. Fisher’s exact test explored associations between food pantry type, NEFPAT category, and challenges. Nonparametric tests were run on non-normally distributed data. Inductive content analysis was used to examine open-ended pandemic-related questions. ResultsThe nutrition environment of most pantries was suboptimal, because no pantry scored in the “gold” category based on total NEFPAT scores (median, 18 of 47). No statistically significant differences were found in the NEFPAT scores by organization type. Most pantries did not provide healthy food nudges or culturally diverse foods. Key COVID-19 challenges encountered consisted of supply- and demand-side issues, including reduced personnel, capacity, and resources, and increased client quantity and demand for food. ConclusionsAssessing the nutrition environment of rural food pantries revealed gaps and strategies for improvement, including the use of healthy nudges and increasing the availability of culturally diverse foods.

On Graphical Shapes of χ2 Statistics of Leading Digits of Irrational Rotations

We discuss the outline of the shapes of graphs of χ 2 statistics for distributions of leading digits of irrational rotations under some conditions on mth convergent. We give some estimates of important coefficients Lk’s, which determine the graphical shapes of χ2 statistics. This means that the denominator qm of mth convergent and the large partial quotient am+1 determine the outline of shapes of graphs, when we observe values of χ 2 statistics with step qm.

A comparative study of changes in smoking cessation attempt rates and related factors before and during COVID-19

This study aimed to identify whether smoking cessation attempts (SCA) for health promotion changed during the coronavirus disease 2019 (COVID-19) pandemic and how the characteristics of people who undertook SCA before versus during COVID-19 differed. This was a secondary data analysis of the South Korean 2019–2021 Community Health Survey data for 163,334 smokers that compared sociodemographic factors, health behaviors, and health status by SCA and year using χ2 statistics and multiple logistic regression analysis. The SCA rate significantly decreased from 72.6 % in 2019 to 44.1 % in 2021. In 2019, the rate was high for those over 60 years old but decreased by half by 2021. The ORs for SCA were higher in women than men in all years and were lower in 2019 for all age groups except those in their 70 s; however, in 2021, the ORs for those in their 20 s were higher than those in their 70 s and were slightly higher for non-high-risk drinkers than for high-risk drinkers. ORs were higher among those trying to lose or gain weight than among those who were not. Despite its health benefits, the SCA rate significantly decreased. Issuing public statements encouraging SCA is critical. Measures are necessary to increase the rate of SCA among people in their 70 s and support those seeking to control their weight for successful smoking cessation. In addition, a strategy to maintain the SCA rate in people in their 20 s is required to ensure their future health.

Zero-Inflated Poisson Regression Modeling of Plant Protein Consumption

Summary This research fitted a discrete distribution for modeling count data. Specifically, Zero-Inflated Poisson (ZIP) regression was used to model plant protein consumption by 400 randomly sampled individuals in Wukari. The data was collected by questionnaire. The ZIP regression model was used based on its ability to model data with excess zeros present in the collected data. Variables considered and used for the analysis are Age, Body Mass Index, Blood Pressure, Occupation, Gender, Weight, Height, Body Reaction, and Consumption Class. The parameters of the ZIP model were estimated using the maximum likelihood estimation technique. The model was tested for Goodness of Fit (GoF) using deviance, scaled deviance, Pearson–χ 2 and scaled Pearson–χ 2 statistics. The results obtained showed that Age, Gender, and Reaction were significant at 5%, and the GoF tests revealed that the Zero-Inflated Poisson regression produces a good fit and is a good model for overcoming the overdispersion effect.

Affected brother as the highest risk factor of type 1 diabetes development in children and adolescents: One center data before implementing type 1 diabetes national screening.

There is an increased risk for childhood type 1 diabetes (T1D) when T1D and type 2 diabetes (T2D) are reported in relatives. Our objective was to evaluate current family risk factors for T1D development before implementing a national screening program for T1D. A population of 879 Caucasian children and adolescents with T1D and 286 healthy controls were enrolled in the study. All participants completed the same questionnaire, which collected information about family history of diabetes over 3 generations. In statistical analyses, frequency tables and χ2 tests evaluated possible multicollinearity among risk factors that were significantly associated with the outcomes. Family history of diabetes was more frequent in controls (n = 75, 26.2%) than in patients with T1D (n = 146, 16.6%, odds ratio (OR) = 1.785, 95% confidence interval (95% CI): 1.299-2.452, degrees of freedom (df) = 12.976, p = 0.004), especially with a family history of T2D (n = 62, 21.7% compared to n = 79, 9.0%, respectively, OR = 2.803, 95% CI: 1.948-4.034, df = 32.669, p < 0.001). Also, there was a tendency for the nuclear family of T1D patients to be more frequently affected by T1D (n = 74, 8.4%) than the controls (n = 15, 5.2%, OR = 1.605, 95% CI: 0.937-2.751, df = 3.081, p = 0.079). The risk of T1D was associated with the closest family members being affected and accelerated over generations. Indeed, it was highest in siblings, especially brothers (OR = 12.985, 95% CI: 0.782-215.743, Fisher's test: p < 0.001). A positive family history of T2D burden among second-degree relatives was 2.728 times more frequent in the control group than in the T1D group (OR = 2.728; 95% Cl: 1.880-3.962, p < 0.001). Furthermore, a positive family history of T1D among first-degree relatives was less frequent in the controls than in the T1D group (OR = 0.124; 95% Cl: 0.030-0.516, p = 0.004). A family history of T1D, but not T2D, is a significant risk factor for T1D development. Indeed, the priority in screening for T1D should be given to first-degree relatives of T1D patients, starting from siblings.

Study on the correlation between bioelectrical impedance analysis index and protein energy consumption in maintenance dialysis patients

BackgroundProtein-energy wasting (PEW) has been reported to be pretty common in maintenance dialysis patients. However, the existing PEW diagnostic standard is limited in clinical use due to the complexity of it. Bioelectrical impedance analysis (BIA), as a non-invasive nutritional assessment method, can objectively and quantitatively analyze the changes of body tissue components under different nutritional states. We aim to explore the association between PEW and BIA and establish a reliable diagnostic model of PEW.MethodsWe collected cross-sectional data of 609 maintenance dialysis patients at the First Affiliated Hospital, College of Medicine, Zhejiang University. PEW was diagnosed according to International Society of Renal Nutrition and Metabolism (ISRNM) criteria. Among them, 448 consecutive patients were included in the training set for the establishment of a diagnostic nomogram. 161 consecutive patients were included for internal validation. 52 patients from Zhejiang Hospital were included for external validation of the diagnostic model. Correlation analysis of BIA indexes with other nutritional indicators was performed. Logistic regression was used to examine the association of BIA indexes with PEW. 12 diagnostic models of PEW in maintenance dialysis patients were developed and the performance of them in terms of discrimination and calibration was evaluated using C statistics and Hosmer–Lemeshow-type χ2 statistics. After comparing to existing diagnostic models, and performing both internal and external validation, we finally established a simple but reliable PEW diagnostic model which may have great value of clinical application.ResultsA total of 609 individuals from First Affiliated Hospital, College of Medicine, Zhejiang University and 52 individuals from Zhejiang Hospital were included. After full adjustment, age, peritoneal dialysis (compared to hemodialysis), subjective global assessment (SGA, compared to non-SGA) and water ratio were independent risk factors, while triglyceride, urea nitrogen, calcium, ferritin, BCM, VFA and phase angle were independent protective factors of PEW. The model incorporated water ratio, VFA, BCM, phase angle and cholesterol revealed best performance. A nomogram was developed according to the results of model performance. The model achieved high C-indexes of 0.843 in the training set, 0.841 and 0.829 in the internal and external validation sets, respectively, and had a well-fitted calibration curve. The net reclassification improvement (NRI) showed 8%, 13%, 2%, 38%, 36% improvement of diagnostic accuracy of our model compared with “PEW score model”, “modified PEW score model”, “3-index model”, “SGA model” and “BIA decision tree model”, respectively.ConclusionsBIA can be used as an auxiliary tool to evaluate PEW risk and may have certain clinical application value.

PD-1 blockade combined with gemcitabine plus nab-paclitaxel is superior to chemotherapy alone in the management of unresectable stage III/IV pancreatic cancer: a retrospective real-world study.

Pancreatic cancer (PC) is widely recognized as one of the most malignant forms of cancer worldwide. Monotherapy with immune checkpoint inhibitors (ICI) has shown limited efficacy in treating this disease. There was controversy surrounding whether combining ICI with chemotherapy provided superior outcomes compared to chemotherapy alone. In this study, patients diagnosed with unresectable stage III/IV pancreatic cancer (PC) were classified as receiving programmed cell death protein 1 (PD-1) blockade plus gemcitabine and nab-paclitaxel (AG regimen) (PD-1/chemo, n=27, 50.9%) or chemotherapy alone (chemo, n=26, 49.1%) arm. The primary study endpoints included progression-free survival (PFS) and overall survival (OS), with an additional assessment of treatment-related adverse events graded as three or higher. Chi-square (χ2) statistics were employed to analyze the clinical differences between the two groups, while Kaplan-Meier curves were used to assess the difference in PFS and OS. Statistical significance was defined as P-values less than 0.05 (P < 0.05). The median follow-up duration was 22 months (range 1-28 months). In the PD-1/chemo arm, the median PFS was eight months, whereas it was 3.5 months in the chemo arm (HR=0.459, 95% CI: 0.252-0.846, P=0.002). Furthermore, the median OS was 15 months in the PD-1/chemo arm and eight months in the chemo arm (HR=0.345, 95% CI: 0.183-0.653, P<0.001). Within the PD-1/chemo arm, 15 (55.6%) patients experienced grade 3 treatment-related adverse events, compared to 13 (50.0%) patients in the chemo arm. PD-1 blockade combined with nab-paclitaxel plus gemcitabine demonstrated superior efficacy to chemotherapy alone for unresectable stage III/IV PC patients. Future studies were warranted to identify immunosensitive patient subgroups within the PC population, ultimately leading to the development of more efficacious therapeutic strategies.

Seroprevalence of SARS-CoV-2 in Niger State: Pilot Cross-Sectional Study.

The COVID-19 pandemic caused by SARS-CoV-2 is causing ongoing human and socioeconomic losses. To know how far the virus has spread in Niger State, Nigeria, a pilot study was carried out to determine the SARS-CoV-2 seroprevalence, patterns, dynamics, and risk factors in the state. A cross-sectional study design and clustered, stratified random sampling strategy were used to select 185 test participants across the state. SARS-CoV-2 IgG and IgM rapid test kits (colloidal gold immunochromatography lateral flow system) were used to determine the presence or absence of antibodies to the virus in the blood of sampled participants across Niger State from June 26 to 30, 2020. The test kits were validated using the blood samples of some of the Nigeria Center for Disease Control-confirmed positive and negative COVID-19 cases in the state. SARS-CoV-2 IgG and IgM test results were entered into the Epi Info questionnaire administered simultaneously with each test. Epi Info was then used to calculate the arithmetic mean and percentage, odds ratio, χ2 statistic, and regression at a 95% CI of the data generated. The seroprevalence of SARS-CoV-2 in Niger State was found to be 25.4% (47/185) and 2.2% (4/185) for the positive IgG and IgM results, respectively. Seroprevalence among age groups, genders, and occupations varied widely. The COVID-19 asymptomatic rate in the state was found to be 46.8% (22/47). The risk analyses showed that the chances of infection are almost the same for both urban and rural dwellers in the state. However, health care workers, those who experienced flulike symptoms, and those who had contact with a person who traveled out of Nigeria in the last 6 months (February to June 2020) were at double the risk of being infected with the virus. More than half (101/185, 54.6%) of the participants in this study did not practice social distancing at any time since the pandemic started. Participants' knowledge, attitudes, and practices regarding COVID-19 are also discussed. The observed Niger State SARS-CoV-2 seroprevalence and infection patterns meansuggest that the virus has widely spread, far more SARS-CoV-2 infections have occurred than the reported cases, and there is a high asymptomatic COVID-19 rate across the state.

Depression and health-related quality of life of patients with type 2 diabetes attending tertiary level hospitals in Dhaka, Bangladesh

IntroductionType 2 diabetes mellitus (T2DM) and depression are closely linked. People with T2DM are at increased risk of developing depression and vice versa. T2DM and depression comorbid conditions adversely affect Health-Related Quality of Life (HRQOL) and management of T2DM. In this study, we assessed depression and HRQOL among patients with T2DM in Dhaka, Bangladesh.MethodsA cross-sectional study was conducted in two tertiary-level hospitals in Dhaka, Bangladesh. Data were collected from 318 patients with T2DM. A set of standard tools, PHQ-9 (for assessing depression) and EuroQol-5D-5L (for assessing the HRQOL), were used. Statistical analyses, including Chi-square and Fisher's exact tests, Wilcoxon (Mann–Whitney), and Spearman's correlation coefficient tests, were performed using SPSS (v.20).ResultsThe majority of the patients (58%) were females, with a mean age (standard deviation) of 52 ± 10 years, and 74% of patients lived in urban areas. The prevalence of depression was 62% (PHQ-9 score ≥ 5). Over three-quarters (76%) reported problems in the anxiety/ depression dimension of EQ-5D, followed by pain/discomfort (74%), mobility (40%), self-care (36%), and usual activities (33%). The depression and T2DM comorbid condition were associated with all the five dimensions of EQ-5D (χ2 statistics with df = 1 was 52.33, 51.13, 52.67, 21.61, 7.92 for mobility, self-care, usual activities, pain/discomfort, and anxiety/ depression dimensions respectively, p- < 0.01). The mean EQ-5D index (0.53 vs. 0.75) and the mean EQ-5D VAS (65 vs. 76) both showed lower values in T2DM patients with depression compared to T2DM patients without depression (Wilcoxon test, p- < 0.001).ConclusionsWe conclude that the majority of the patients with T2DM had comorbid conditions, and the HRQOL was negatively affected by comorbid depression in T2DM patients. This suggests the importance of timely screening, diagnosis, treatment, and follow-up of comorbid depression in T2DM patients to improve overall health and QOL.

Disparate potential for readmission prevention exists among inpatient and outpatient procedures in a minimally invasive surgery practice

BackgroundAdministrators have focused on decreasing postoperative readmissions for cost reduction without fully understanding their preventability. This study describes the development and implementation of a surgeon-led readmission review process that assessed preventability. MethodsA gastrointestinal surgical group at a tertiary referral hospital developed and implemented a template to analyze inpatient and outpatient readmissions. Monthly stakeholder assessments reviewed and categorized readmissions as potentially preventable or not preventable. Continuous variables were examined by the Student’s t test and reported as means and standard deviations. Categorical variables were examined by the Pearson χ2 statistic and Fisher’s exact test. ResultsThere were 61 readmission events after 849 inpatient operations (7.2%) and 16 after 856 outpatient operations (1.9%), the latter of which were all classified as potentially preventable. Colorectal procedures represented 65.6% of readmissions despite being only 37.2% of all cases. The majority (67.2%) of readmission events were not preventable. Compared to the not-preventable group, the potentially preventable group experienced more dehydration (30.0% vs 9.8%, P = .045) and ileostomy creation (78.6% vs 33.3%, P = .017). The potential for outpatient management to prevent readmission was significantly higher in the potentially preventable group (40.0% vs 0.0%, P < .001), as was premature discharge prevention (35.0% vs 0.0%, P < .001). ConclusionThe use of the standardized template developed for analyzing readmission events after inpatient and outpatient procedures identified a disparate potential for readmission prevention. This finding suggests that a singular focus on readmission reduction is misguided, with further work needed to evaluate and implement appropriate quality-based strategies.

Multiple scattering calculations for proton beams: Comparison of results from the general-purpose Monte Carlo codes penh, fluka and topas

Purpose:To test the multiple Coulomb scattering theories implemented in the Monte Carlo simulation codes penh, fluka and topas. Methods:Simulations with the three codes of proton beams with initial energies between 100 and 220 MeV impinging normally on slabs of 14 different compositions and various thicknesses were performed. The simulated angular distributions of transmitted protons are very approximately Gaussian with a characteristic angle θ0, which measures the spread of the distribution. The characteristic angles resulting from the simulations are compared to experimental data available from two experiments. The degree of agreement is quantified by the χ2 statistic. The 151 cases considered are analyzed by grouping the data in various ways (all together, by experiment, according to the energy of the proton beam or the slab material). Results:In general, penh produced the better description of the experimental data. If all data are included, the χ2 values were 3.7±0.6 for penh, 18.7±0.4 for fluka and 7.4±1.5 for topas. The ranges in the values of χ2 obtained for the various data groups are [0.1±0.2;10.7±4.1] for penh, [0.10±0.03;221.1±7.8] for fluka, and [0.2±0.3;46.2±26.4] for topas. The minimum and maximum values in these ranges occur, in the three codes, for the Zn and the brass slabs, respectively, with 158.6MeV protons. Conclusions:The three codes provide a reasonably accurate description of multiple scattering distributions of protons transmitted through material slabs. Brass is the material whose experimental data are worst described by the three codes analyzed.

EXPOSURE TO BIOMASS FUEL SMOKE AND RISK OF CHILD MORBIDITY: AN ANALYSIS ON SOUTH AND SOUTH-EAST ASIAN COUNTRIES

Around 03 billion people still cook using biomass fuels, these cooking practices are hazardous and produce a wide range of health-damaging pollutants causing high level household air pollution. Most of these people using solid fuels belong to lower wealth quintile household and resides in low and middle-income countries. The women and young children who spend most of their time near the domestic hearth are comparatively more exposed to toxic amount of household air pollutants every day. The current study compares the scenario of child respiratory health; assessing the occurrence of ARI and cough among children aged under five in South and Southeast Asian countries. The current study is comprised of analysis of Demographic Health Survey data for Afghanistan, India, Nepal, Cambodia, Bangladesh and Philippines. A comparative study was conducted between the selected countries. The differences in categorical variables were tested using Pearson’s χ2 Statistics, since both treatment and outcome variable in the study are binomial, a simultaneous equation was used (probit regression model). The results indicated that there is an increased likelihood of occurrence of ARI and cough among children aged under five belonging to the households using solid fuel in the selected South and Southeast Asian countries

Dynamic prediction modeling of postoperative mortality among patients undergoing surgical aortic valve replacement in a statewide cohort over a 12-year period

ObjectiveClinical prediction models for surgical aortic valve replacement mortality, are valuable decision tools but are often limited in their ability to account for changes in medical practice, patient selection, and the risk of outcomes over time. Recent research has identified methods to update models as new data accrue, but their effect on model performance has not been rigorously tested. MethodsThe study population included 44,546 adults who underwent an isolated surgical aortic valve replacement from January 1, 1999, to December 31, 2018, statewide in Pennsylvania. After chronologically splitting the data into training and validation sets, we compared calibration, discrimination, and accuracy measures amongst a nonupdating model to 2 methods of model updating: calibration regression and the novel dynamic logistic state space model. ResultsThe risk of mortality decreased significantly during the validation period (P < .01) and the nonupdating model demonstrated poor calibration and reduced accuracy over time. Both updating models maintained better calibration (Hosmer-Lemeshow χ2 statistic) than the nonupdating model: nonupdating (156.5), calibration regression (4.9), and dynamic logistic state space model (8.0). Overall accuracy (Brier score) was consistently better across both updating models: dynamic logistic state space model (0.0252), calibration regression (0.0253), and nonupdating (0.0256). Discrimination improved with the dynamic logistic state space model (area under the curve, 0.696) compared with the nonupdating model (area under the curve, 0.685) and calibration regression method (area under the curve, 0.687). ConclusionsDynamic model updating can improve model accuracy, discrimination, and calibration. The decision as to which method to use may depend on which measure is most important in each clinical context. Because competing therapies have emerged for valve replacement models, updating may guide clinical decision making.

COVID-19 data, mitigation policies and Newcomb–Benford law

We study how reliable are available data on COVID-19 cases and deaths in different countries. Our analysis is based on a modification of the law of anomalous numbers, the Newcomb–Benford law, applied to the daily number of deaths and new cases in each country. We first revisit the Newcomb–Benford law and show how to avoid false negative compliance with the data. We then compare the χ2 statistics deviation from this law to a number of social and economic indices for each country by computing the Spearman rank-order correlation between them and the χ2 deviation. We considered the proportion of excess deaths for those countries with sufficient available data for a good estimate and obtained similar results: less democratic, less transparent, and more corrupt countries tend to have data of lesser quality. We also discussed the limitations of the present approach and which countries the results were significant for.

Assessment of cardio-renal-hepatic function in patients with valvular heart disease: a multi-biomarker approach—the cardio-renal-hepatic score

BackgroundValvular heart disease (VHD) can cause damage to extra-cardiac organs, and lead to multi-organ dysfunction. However, little is known about the cardio-renal-hepatic co-dysfunction, as well as its prognostic implications in patients with VHD. The study sought to develop a multi-biomarker index to assess heart, kidney, and liver function in an integrative fashion, and investigate the prognostic role of cardio-renal-hepatic function in VHD.MethodsUsing a large, contemporary, prospective cohort of 6004 patients with VHD, the study developed a multi-biomarker score for predicting all-cause mortality based on biomarkers reflecting heart, kidney, and liver function (N-terminal pro-B-type natriuretic peptide [NT-proBNP], creatinine, and albumin). The score was externally validated in another contemporary, prospective cohort of 3156 patients with VHD.ResultsDuring a median follow up of 731 (704–748) days, 594 (9.9%) deaths occurred. Increasing levels of NT-proBNP, creatinine, and albumin were independently and monotonically associated with mortality, and a weighted multi-biomarker index, named the cardio-renal-hepatic (CRH) score, was developed based on Cox regression coefficients of these biomarkers. The CRH score was a strong and independent predictor of mortality, with 1-point increase carrying over two times of mortality risk (overall adjusted hazard ratio [95% confidence interval]: 2.095 [1.891–2.320], P < 0.001). The score provided complementary prognostic information beyond conventional risk factors (C index: 0.78 vs 0.81; overall net reclassification improvement index [95% confidence interval]: 0.255 [0.204–0.299]; likelihood ratio test P < 0.001), and was identified as the most important predictor of mortality by the proportion of explainable log-likelihood ratio χ2 statistics, the best subset analysis, as well as the random survival forest analysis in most types of VHD. The predictive performance of the score was also demonstrated in patients under conservative treatment, with normal left ventricular systolic function, or with primary VHD. It achieved satisfactory discrimination (C index: 0.78 and 0.72) and calibration in both derivation and validation cohorts.ConclusionsA multi-biomarker index was developed to assess cardio-renal-hepatic function in patients with VHD. The cardio-renal-hepatic co-dysfunction is a powerful predictor of mortality and should be considered in clinical management decisions.

Impact of an Automated Closed-Loop Communication and Tracking Tool on the Rate of Recommendations for Additional Imaging in Thoracic Radiology Reports

ObjectiveAssess the effects of feedback reports and implementing a closed-loop communication system on rates of recommendations for additional imaging (RAIs) in thoracic radiology reports. MethodsIn this retrospective, institutional review board–approved study at an academic quaternary care hospital, we analyzed 176,498 thoracic radiology reports during a pre-intervention (baseline) period from April 1, 2018, to November 30, 2018; a feedback report only period from December 1, 2018, to September 30, 2019; and a closed-loop communication system plus feedback report (IT intervention) period from October 1, 2019, to December 31, 2020, promoting explicit documentation of rationale, time frame, and imaging modality for RAI, defined as complete RAI. A previously validated natural language processing tool was used to classify reports with an RAI. Primary outcome of rate of RAI was compared using a control chart. Multivariable logistic regression determined factors associated with likelihood of RAI. We also estimated the completeness of RAI in reports comparing IT intervention to baseline using χ2 statistic. ResultsThe natural language processing tool classified 3.2% (5,682 of 176,498) reports as having an RAI; 3.5% (1,783 of 51,323) during the pre-intervention period, 3.8% (2,147 of 56,722) during the feedback report only period (odds ratio: 1.1, P = .03), and 2.6% (1,752 of 68,453) during the IT intervention period (odds ratio: 0.60, P < .001). In subanalysis, the proportion of incomplete RAI decreased from 84.0% (79 of 94) during the pre-intervention period to 48.5% (47 of 97) during the IT intervention period (P < .001). DiscussionFeedback reports alone increased RAI rates, and an IT intervention promoting documentation of complete RAI in addition to feedback reports led to significant reductions in RAI rate, incomplete RAI, and improved overall completeness of the radiology recommendations.

Conceptualisation and Development of a values-based scale of emergency physicians’ professional identities

BackgroundPhysicians’ values about what constitute their professional identities are integral in understanding how they ascribe meaning to their practice. However, there is no general consensus on the conceptualization and measurement of physicians’ professional identities. This study developed and validated a values-based scale for measuring physicians’ professional identities.MethodsA hybrid research method was used to gather both qualitative and quantitative data. We employed literature review, semi-structured interview, Q-sorting exercise to examine the conceptualization of emergency physicians’ professional identities and to initially develop a 40-item scale. A panel of five experts assessed the scale’s content validity. Using 150 emergency physicians as our sample, we conducted Confirmatory Factor Analyses (CFA) to test the fit of our hypothesised four-factor model based on our preliminary findings.ResultsInitial CFA suggested revisions to the model. Following theoretical assumptions and modification indices, the model was revised and adjusted to a four-factor 20 item Emergency Physicians Professional Identities Value Scale (EPPIVS) with acceptable fit statistics χ2 = 389.38, df = 164, Normed χ2 = 2.374, GFI = 0.788, CFI = 0.862, RMSEA = 0.096. The Cronbach’s alpha, McDonald’s Omega reliability and composite reliability of the subscales ranged from α: 0.748 to 0.868, Omega: 0.759 to 0.868 and CR: 0.748 to 0.851, respectively.ConclusionThe results indicate that the EPPIVS is a valid and reliable scale for measuring physicians’ professional identities. Further research on the sensitivity of this instrument to important changes over career progression in emergency medicine is warranted.