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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(4): 918-924, 2024 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-39170018

RESUMO

Objective: To construct a model for predicting recidivism in violence in community-based schizophrenia spectrum disorder patients (SSDP) by adopting a joint modeling method. Methods: Based on the basic data on severe mental illness in Southwest China between January 2017 and June 2018, 4565 community-based SSDP with baseline violent behaviors were selected as the research subjects. We used a growth mixture model (GMM) to identify patterns of medication adherence and social functioning. We then fitted the joint model using a zero-inflated negative binomial regression model and compared it with traditional static models. Finally, we used a 10-fold training-test cross validation framework to evaluate the models' fitting and predictive performance. Results: A total of 157 patients (3.44%) experienced recidivism in violence. Medication compliance and social functioning were fitted into four patterns. In the counting model, age, marital status, educational attainment, economic status, historical types of violence, and medication compliance patterns were predictive factors for the frequency of recidivism of violence (P<0.05). In the zero-inflated model, age, adverse drug reactions, historical types of violence, medication compliance patterns, and social functioning patterns were predictive factors for the recidivism in violence (P<0.05). For the joint model, the average value of Akaike information criterion (AIC) for the train set was 776.5±9.4, the average value of root mean squared error (RMSE) for the testing set was 0.168±0.013, and the average value of mean absolute error (MAE) for the testing set was 0.131±0.018, which were all lower than those of the traditional static models. Conclusion: Joint modeling is an effective statistical strategy for identifying and processing dynamic variables, exhibiting better predictive performance than that of the traditional static models. It can provide new ideas for promoting the construction of comprehensive intervention systems.


Assuntos
Reincidência , Esquizofrenia , Violência , Humanos , Esquizofrenia/tratamento farmacológico , China , Violência/estatística & dados numéricos , Reincidência/estatística & dados numéricos , Feminino , Masculino , Adesão à Medicação/estatística & dados numéricos , Adulto , Pessoa de Meia-Idade
2.
Sci Rep ; 14(1): 17520, 2024 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-39079984

RESUMO

Alcohol consumption in Tanzania exceeds the global average. While sociodemographic difference in alcohol consumption in Tanzania have been studied, the relationship between psycho-cognitive phenomena and alcohol consumption has garnered little attention. Our study examines how depressive symptoms and cognitive performance affect alcohol consumption, considering sociodemographic variations. We interviewed 2299 Tanzanian adults, with an average age of 53 years, to assess their alcohol consumption, depressive symptoms, cognitive performance, and sociodemographic characteristics using a zero-inflated negative binomial regression model. The logistic portion of our model revealed that the likelihood alcohol consumption increased by 8.4% (95% confidence interval [CI] 3.6%, 13.1%, p < 0.001) as depressive symptom severity increased. Conversely, the count portion of the model indicated that with each one-unit increase in the severity of depressive symptoms, the estimated number of drinks decreased by 2.3% (95% CI [0.4%, 4.0%], p = .016). Additionally, the number of drinks consumed decreased by 4.7% (95% CI [1.2%, 8.1%], p = .010) for each increased cognitive score. Men exhibited higher alcohol consumption than women, and Christians tended to consume more than Muslims. These findings suggest that middle-aged and elderly adults in Tanzania tend to consume alcohol when they feel depressed but moderate their drinking habits by leveraging their cognitive abilities.


Assuntos
Consumo de Bebidas Alcoólicas , Cognição , Depressão , Humanos , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Masculino , Feminino , Pessoa de Meia-Idade , Tanzânia/epidemiologia , Idoso , Depressão/epidemiologia , Depressão/psicologia , Emoções , Adulto , População da África Oriental
3.
Biometrics ; 80(3)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39073775

RESUMO

Recent breakthroughs in spatially resolved transcriptomics (SRT) technologies have enabled comprehensive molecular characterization at the spot or cellular level while preserving spatial information. Cells are the fundamental building blocks of tissues, organized into distinct yet connected components. Although many non-spatial and spatial clustering approaches have been used to partition the entire region into mutually exclusive spatial domains based on the SRT high-dimensional molecular profile, most require an ad hoc selection of less interpretable dimensional-reduction techniques. To overcome this challenge, we propose a zero-inflated negative binomial mixture model to cluster spots or cells based on their molecular profiles. To increase interpretability, we employ a feature selection mechanism to provide a low-dimensional summary of the SRT molecular profile in terms of discriminating genes that shed light on the clustering result. We further incorporate the SRT geospatial profile via a Markov random field prior. We demonstrate how this joint modeling strategy improves clustering accuracy, compared with alternative state-of-the-art approaches, through simulation studies and 3 real data applications.


Assuntos
Teorema de Bayes , Simulação por Computador , Perfilação da Expressão Gênica , Análise por Conglomerados , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/estatística & dados numéricos , Humanos , Transcriptoma , Cadeias de Markov , Modelos Estatísticos , Interpretação Estatística de Dados
4.
Front Genet ; 15: 1356709, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725485

RESUMO

Recent technology breakthroughs in spatially resolved transcriptomics (SRT) have enabled the comprehensive molecular characterization of cells whilst preserving their spatial and gene expression contexts. One of the fundamental questions in analyzing SRT data is the identification of spatially variable genes whose expressions display spatially correlated patterns. Existing approaches are built upon either the Gaussian process-based model, which relies on ad hoc kernels, or the energy-based Ising model, which requires gene expression to be measured on a lattice grid. To overcome these potential limitations, we developed a generalized energy-based framework to model gene expression measured from imaging-based SRT platforms, accommodating the irregular spatial distribution of measured cells. Our Bayesian model applies a zero-inflated negative binomial mixture model to dichotomize the raw count data, reducing noise. Additionally, we incorporate a geostatistical mark interaction model with a generalized energy function, where the interaction parameter is used to identify the spatial pattern. Auxiliary variable MCMC algorithms were employed to sample from the posterior distribution with an intractable normalizing constant. We demonstrated the strength of our method on both simulated and real data. Our simulation study showed that our method captured various spatial patterns with high accuracy; moreover, analysis of a seqFISH dataset and a STARmap dataset established that our proposed method is able to identify genes with novel and strong spatial patterns.

5.
BMC Bioinformatics ; 24(1): 318, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37608264

RESUMO

BACKGROUND: Single-cell RNA sequencing (scRNA-seq) technology has enabled assessment of transcriptome-wide changes at single-cell resolution. Due to the heterogeneity in environmental exposure and genetic background across subjects, subject effect contributes to the major source of variation in scRNA-seq data with multiple subjects, which severely confounds cell type specific differential expression (DE) analysis. Moreover, dropout events are prevalent in scRNA-seq data, leading to excessive number of zeroes in the data, which further aggravates the challenge in DE analysis. RESULTS: We developed iDESC to detect cell type specific DE genes between two groups of subjects in scRNA-seq data. iDESC uses a zero-inflated negative binomial mixed model to consider both subject effect and dropouts. The prevalence of dropout events (dropout rate) was demonstrated to be dependent on gene expression level, which is modeled by pooling information across genes. Subject effect is modeled as a random effect in the log-mean of the negative binomial component. We evaluated and compared the performance of iDESC with eleven existing DE analysis methods. Using simulated data, we demonstrated that iDESC had well-controlled type I error and higher power compared to the existing methods. Applications of those methods with well-controlled type I error to three real scRNA-seq datasets from the same tissue and disease showed that the results of iDESC achieved the best consistency between datasets and the best disease relevance. CONCLUSIONS: iDESC was able to achieve more accurate and robust DE analysis results by separating subject effect from disease effect with consideration of dropouts to identify DE genes, suggesting the importance of considering subject effect and dropouts in the DE analysis of scRNA-seq data with multiple subjects.


Assuntos
Modelos Estatísticos , Transcriptoma , Humanos , Análise de Sequência de RNA
6.
Public Health ; 222: 134-139, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37544123

RESUMO

OBJECTIVES: The aim of this article was to explore the association between adverse childhood experiences (ACEs) and the Charlson comorbidity index (CCI) and to provide valuable information for public health professionals and policymakers to improve quality of life and reduce mortality. STUDY DESIGN: A cross-sectional analysis was conducted using data pooled from the 2020 Behavioral Risk Factor Surveillance System (BRFSS). METHODS: This study involved 102,393 US adult participants from the 2020 BRFSS. The zero-inflated negative binomial (ZINB) and mixed graphical model (MGM) models were used to explore the effect of ACEs on CCI and the interaction between ACEs. RESULTS: In the count part of the model (CCI ≥0), sexual abuse had the strongest association with CCI (relative risk [RR] = 1.111, P < 0.001). In the logit part of the model (CCI = 0), the likelihood of having CCI equal to 0 decreased by 23.0% for household substance abuse, which was the highest percentage decrease for all ACEs. Compared to those with ACE scores equal to 0, individuals with ACE scores ≥4 have an expected CCI RR of 1.222, and the likelihood of having CCI equal to 0 decreased by 50.2%. Household substance abuse and incarceration history in the home had the strongest association among interactions of ACEs (0.85). CONCLUSIONS: Associations between ACEs and CCI were observed in this study, and these associations differed between genders. The findings of this study provide data to design strategies for disease prevention and improvement of quality of life.


Assuntos
Experiências Adversas da Infância , Transtornos Relacionados ao Uso de Substâncias , Adulto , Humanos , Masculino , Feminino , Qualidade de Vida , Estudos Transversais , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Comorbidade
7.
Brief Bioinform ; 24(5)2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37507115

RESUMO

Single cell RNA-sequencing (scRNA-seq) technology has significantly advanced the understanding of transcriptomic signatures. Although various statistical models have been used to describe the distribution of gene expression across cells, a comprehensive assessment of the different models is missing. Moreover, the growing number of features associated with scRNA-seq datasets creates new challenges for analytical accuracy and computing speed. Here, we developed a Python-based package (TensorZINB) to solve the zero-inflated negative binomial (ZINB) model using the TensorFlow deep learning framework. We used a sequential initialization method to solve the numerical stability issues associated with hurdle and zero-inflated models. A recursive feature selection protocol was used to optimize feature selections for data processing and downstream differentially expressed gene (DEG) analysis. We proposed a class of hybrid models combining nested models to further improve the model's performance. Additionally, we developed a new method to convert a continuous distribution to its equivalent discrete form, so that statistical models can be fairly compared. Finally, we showed that the proposed TensorFlow algorithm (TensorZINB) was numerically stable and that its computing speed and performance were superior to those of existing ZINB solvers. Moreover, we implemented seven hurdle and zero-inflated statistical models in Python and systematically assessed their performance using a real scRNA-seq dataset. We demonstrated that the ZINB model achieved the lowest Akaike information criterion compared with other models tested. Taken together, TensorZINB was accurate, efficient and scalable for the implementation of ZINB and for large-scale scRNA-seq data analysis with DEG identification.


Assuntos
Perfilação da Expressão Gênica , Modelos Estatísticos , Distribuição de Poisson , Perfilação da Expressão Gênica/métodos , RNA , Análise de Sequência de RNA/métodos
8.
J Clin Med ; 12(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37373567

RESUMO

Psychopathological symptoms are common sequelae after traumatic brain injury (TBI), leading to increased personal and societal burden. Previous studies on factors influencing Post-traumatic Stress Disorder (PTSD), Generalized Anxiety Disorder (GAD), and Major Depressive Disorder (MDD) after TBI have produced inconclusive results, partly due to methodological limitations. The current study investigated the influence of commonly proposed factors on the clinical impairment, occurrence, frequency, and intensity of symptoms of PTSD, GAD, and MDD after TBI. The study sample comprised 2069 individuals (65% males). Associations between psychopathological outcomes and sociodemographic, premorbid, and injury-related factors were analyzed using logistic regression, standard, and zero-inflated negative binomial models. Overall, individuals experienced moderate levels of PTSD, GAD, and MDD. Outcomes correlated with early psychiatric assessments across domains. The clinical impairment, occurrence, frequency, and intensity of all outcomes were associated with the educational level, premorbid psychiatric history, injury cause, and functional recovery. Distinct associations were found for injury severity, LOC, and clinical care pathways with PTSD; age and LOC:sex with GAD; and living situation with MDD, respectively. The use of suitable statistical models supported the identification of factors associated with the multifactorial etiology of psychopathology after TBI. Future research may apply these models to reduce personal and societal burden.

9.
BMC Public Health ; 23(1): 1197, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37344872

RESUMO

BACKGROUND: Choosing appropriate models for count health outcomes remains a challenge to public health researchers and the validity of the findings thereof. For count data, the mean-variance relationship and proportion of zeros is a major determinant of model choice. This study aims to compare and identify the best Bayesian count modelling technique for the number of childhood vaccine uptake in Nigeria. METHODS: We explored the performances of Poisson, negative binomial and their zero-inflated forms in the Bayesian framework using cross-sectional data pooled from the Nigeria Demographic and Health Survey conducted between 2003 and 2018. In multivariable analysis, these Bayesian models were used to identify factors associated with the number of vaccine uptake among children. Model selection was based on the -2 Log-Likelihood (-2 Log LL), Leave-One-Out Cross-Validation Information Criterion (LOOIC) and Watanabe-Akaike/Widely Applicable Information Criterion (WAIC). RESULTS: Exploratory analysis showed the presence of excess zeros and overdispersion with a mean of 4.36 and a variance of 12.86. Observably, there was a significant increase in vaccine uptake over time. Significant factors included the mother's age, level of education, religion, occupation, desire for last-child, place of delivery, exposure to media, birth order of the child, wealth status, number of antenatal care visits, postnatal attendance, healthcare decision maker, community poverty, community illiteracy, community unemployment, rural proportion and number of health facilities per 100,000. The zero-inflated negative binomial model was best fit with -2Log LL of -27171.47, LOOIC of 54464.2, and WAIC of 54588.0. CONCLUSION: The Bayesian zero-inflated negative binomial model was most appropriate to identify factors associated with the number of childhood vaccines received in Nigeria due to the presence of excess zeros and overdispersion. Improving vaccine uptake by addressing the associated risk factors should be promptly embraced.


Assuntos
Modelos Estatísticos , Gravidez , Humanos , Feminino , Teorema de Bayes , Nigéria , Estudos Transversais , Fatores de Risco , Distribuição de Poisson
10.
Stat Methods Med Res ; 32(7): 1300-1317, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37167422

RESUMO

The zero-inflated negative binomial distribution has been widely used for count data analyses in various biomedical settings due to its capacity of modeling excess zeros and overdispersion. When there are correlated count variables, a bivariate model is essential for understanding their full distributional features. Examples include measuring correlation of two genes in sparse single-cell RNA sequencing data and modeling dental caries count indices on two different tooth surface types. For these purposes, we develop a richly parametrized bivariate zero-inflated negative binomial model that has a simple latent variable framework and eight free parameters with intuitive interpretations. In the scRNA-seq data example, the correlation is estimated after adjusting for the effects of dropout events represented by excess zeros. In the dental caries data, we analyze how the treatment with Xylitol lozenges affects the marginal mean and other patterns of response manifested in the two dental caries traits. An R package "bzinb" is available on Comprehensive R Archive Network.


Assuntos
Cárie Dentária , Humanos , Modelos Estatísticos , Distribuição Binomial , Análise de Dados , Distribuição de Poisson
11.
Stat Med ; 42(13): 2061-2081, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37071977

RESUMO

Mediation analyses play important roles in making causal inference in biomedical research to examine causal pathways that may be mediated by one or more intermediate variables (ie, mediators). Although mediation frameworks have been well established such as counterfactual-outcomes (ie, potential-outcomes) models and traditional linear mediation models, little effort has been devoted to dealing with mediators with zero-inflated structures due to challenges associated with excessive zeros. We develop a novel mediation modeling approach to address zero-inflated mediators containing true zeros and false zeros. The new approach can decompose the total mediation effect into two components induced by zero-inflated structures: the first component is attributable to the change in the mediator on its numerical scale which is a sum of two causal pathways and the second component is attributable only to its binary change from zero to a non-zero status. An extensive simulation study is conducted to assess the performance and it shows that the proposed approach outperforms existing standard causal mediation analysis approaches. We also showcase the application of the proposed approach to a real study in comparison with a standard causal mediation analysis approach.


Assuntos
Análise de Mediação , Modelos Estatísticos , Humanos , Simulação por Computador , Modelos Lineares , Causalidade
12.
BMC Cancer ; 23(1): 293, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37004010

RESUMO

BACKGROUND: This cross-sectional cohort study assessed the inequalities in oesophageal carcinoma risk by age, sex and nativity in Kuwait: 1980-2019. METHODS: Using oesophageal cancer incidence data from the Kuwait National Cancer Registry, relevant Kuwaiti population data and World Standard Population as a reference, age-standardized incidence rates (ASIR) (per 100,000 person-years) overall and by subcohorts were computed. The incident oesophageal cancer cases count was overdispersed with excessive structural zeros, therefore, it was analyzed using multivariable zero-inflated negative binomial (ZINB) model. RESULTS: Overall ASIR of oesophageal cancer was 10.51 (95% CI:  6.62-14.41). The multivariable ZINB model showed that compared with the younger age category (< 30 years), the individuals in higher age groups showed a significant (p < 0.001) increasing tendency to develop the oesophageal cancer.  Furthermore, compared with the non-Kuwaiti residents, the Kuwaiti nationals were significantly (p < 0.001) more likely to develop oesophageal cancer during the study period. Moreover, compared with 1980-84 period, ASIRs steadily and significantly  (p < 0.005) declined in subsequent periods till 2015-19. CONCLUSIONS: A high incidence of oesophageal cancer was recorded in Kuwait, which consistently declined from 1980 to 2019. Older adults (aged ≥ 60 years) and, Kuwaiti nationals were at high risk of oesophageal cancer. Focused educational intervention may minimize oesophageal cancer incidence in high-risk groups in this and other similar settings. Future studies may contemplate to evaluate such an intervention.


Assuntos
Carcinoma , Neoplasias Esofágicas , Humanos , Idoso , Estudos Transversais , Incidência , Kuweit/epidemiologia , Neoplasias Esofágicas/epidemiologia
13.
Stat Med ; 42(10): 1512-1524, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-36791465

RESUMO

Many statistical methods have been applied to VAERS (vaccine adverse event reporting system) database to study the safety of COVID-19 vaccines. However, none of these methods considered the adverse event (AE) ontology. The AE ontology contains important information about biological similarities between AEs. In this paper, we develop a model to estimate vaccine-AE associations while incorporating the AE ontology. We model a group of AEs using the zero-inflated negative binomial model and then estimate the vaccine-AE association using the empirical Bayes approach. This model handles the AE count data with excess zeros and allows borrowing information from related AEs. The proposed approach was evaluated by simulation studies and was further illustrated by an application to the Vaccine Adverse Event Reporting System (VAERS) dataset. The proposed method is implemented in an R package available at https://github.com/umich-biostatistics/zGPS.AO.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Sistemas de Notificação de Reações Adversas a Medicamentos , Teorema de Bayes , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Estados Unidos , Vacinas/efeitos adversos
14.
Int J Environ Health Res ; 33(9): 864-880, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35412402

RESUMO

The COVID-19 pandemic caused enormous destruction to global health and the economy and has surged worldwide with colossal morbidity and mortality. The pattern of the COVID infection varies in diverse regions of the world based on the variations in the geographic environment. The multivariate generalized linear regression models: zero-inflated negative binomial regression, and the zero-inflated Poisson regression model, have been employed to determine the significant meteorological factors responsible for the spread of the pandemic in different continents. Asia experienced a high COVID-19 infection, and death was extreme in Europe. Relative humidity, air pressure, and wind speed are the salient factors significantly impacting the spread of COVID-19 in Africa. Death due to COVID-19 in Asia is influenced by air pressure, temperature, precipitation, and relative humidity. Air pressure and temperature substantially affect the spread of the pandemic in Europe.


There is a substantial variation of the impacts of environmental variables on the spread of the COVID-19 pandemic in different parts of the world.Temperature and air pressure significantly impact the number of infections and death due to COVID-19 in Europe.Relative humidity, temperature, sky clearness, and wind speed posed significant positive effects on COVID-19 in AfricaThe spread of COVID-19 infection and death is maximum in low temperatures.The confounding effect of the maximum number of meteorological factors minimizes the transmission of the pandemic.


Assuntos
Poluição do Ar , COVID-19 , Humanos , COVID-19/epidemiologia , Poluição do Ar/análise , Pandemias , Temperatura , Europa (Continente)/epidemiologia
15.
J Environ Manage ; 328: 116788, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36525738

RESUMO

Wildfires have changed in recent decades. The catastrophic wildfires make it necessary to have accurate predictive models on a country scale to organize firefighting resources. In Mediterranean countries, the number of wildfires is quite high but they are mainly concentrated around summer months. Because of seasonality, there are territories where the number of fires is zero in some months and is overdispersed in others. Zero-inflated negative binomial mixed models are adapted to this type of data because they can describe patterns that explain both number of fires and their non-occurrence and also provide useful prediction tools. In addition to model-based predictions, a parametric bootstrap method is applied for estimating mean squared errors and constructing prediction intervals. The statistical methodology and developed software are applied to model and to predict number of wildfires in Spain between 2002 and 2015 by provinces and months.


Assuntos
Incêndios , Incêndios Florestais , Espanha , Modelos Estatísticos , Estações do Ano
16.
bioRxiv ; 2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38168368

RESUMO

Recent technology breakthroughs in spatially resolved transcriptomics (SRT) have enabled the comprehensive molecular characterization of cells whilst preserving their spatial and gene expression contexts. One of the fundamental questions in analyzing SRT data is the identification of spatially variable genes whose expressions display spatially correlated patterns. Existing approaches are built upon either the Gaussian process-based model, which relies on ad hoc kernels, or the energy-based Ising model, which requires gene expression to be measured on a lattice grid. To overcome these potential limitations, we developed a generalized energy-based framework to model gene expression measured from imaging-based SRT platforms, accommodating the irregular spatial distribution of measured cells. Our Bayesian model applies a zero-inflated negative binomial mixture model to dichotomize the raw count data, reducing noise. Additionally, we incorporate a geostatistical mark interaction model with a generalized energy function, where the interaction parameter is used to identify the spatial pattern. Auxiliary variable MCMC algorithms were employed to sample from the posterior distribution with an intractable normalizing constant. We demonstrated the strength of our method on both simulated and real data. Our simulation study showed that our method captured various spatial patterns with high accuracy; moreover, analysis of a seqFISH dataset and a STARmap dataset established that our proposed method is able to identify genes with novel and strong spatial patterns.

17.
Adv Gerontol ; 36(5): 627-637, 2023.
Artigo em Russo | MEDLINE | ID: mdl-38180361

RESUMO

The frequency of seeking emergency medical care (EC) can be mediated by the characteristics of the patient's social status, his health literacy (HL) but not only by the clinical signs of the disease, health status. The goal of the cross-sectional survey was to identify factors determining the frequency of applying for EC by the young-aged, middle-aged (18-59 years) and elderly (60-74 years) patients of the primary health organizations in the Arkhangelsk Region and the Komi Republic (North-West Russia). Logistic regression (LR) was used to identify factors mediating the fact of applying for EC; zero-inflated negative binomial regression (ZINB) - to identify factors mediating the frequency of appeals. The majority of elderly respondents in the Arkhangelsk Region (72,5%) and the Komi Republic (74,1%) applied for EC at least once during the calendar year; among the young-aged and middle-aged respondents - 45,3% and 52,1% respectively. In the group of young-aged and middle-aged respondents, a higher frequency of appeals for EC is mediated by the age, low self-esteem of the well-being and health status, a chronic disease(s) affecting daily well-being in anamnesis, a low level of HL; in the group of the elderly respondents - by the fact of absence of a spouse, low self-esteem of the well-being, a chronic disease(s) affecting daily well-being in anamnesis, low levels of HL respectively. The obtained results obtained can be used to identify the «risk group¼ of patients of the primary health organizations who have a higher probability of applying for EC, and to organize additional preventive work with the min primary health organizations.


Assuntos
Serviços Médicos de Emergência , Idoso , Humanos , Pessoa de Meia-Idade , Estudos Transversais , Modelos Estatísticos , Doença Crônica , Atenção Primária à Saúde
18.
BMC Med Res Methodol ; 22(1): 211, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927612

RESUMO

BACKGROUND: Hospital length of stay (LOS) is a key indicator of hospital care management efficiency, cost of care, and hospital planning. Hospital LOS is often used as a measure of a post-medical procedure outcome, as a guide to the benefit of a treatment of interest, or as an important risk factor for adverse events. Therefore, understanding hospital LOS variability is always an important healthcare focus. Hospital LOS data can be treated as count data, with discrete and non-negative values, typically right skewed, and often exhibiting excessive zeros. In this study, we compared the performance of the Poisson, negative binomial (NB), zero-inflated Poisson (ZIP), and zero-inflated negative binomial (ZINB) regression models using simulated and empirical data. METHODS: Data were generated under different simulation scenarios with varying sample sizes, proportions of zeros, and levels of overdispersion. Analysis of hospital LOS was conducted using empirical data from the Medical Information Mart for Intensive Care database. RESULTS: Results showed that Poisson and ZIP models performed poorly in overdispersed data. ZIP outperformed the rest of the regression models when the overdispersion is due to zero-inflation only. NB and ZINB regression models faced substantial convergence issues when incorrectly used to model equidispersed data. NB model provided the best fit in overdispersed data and outperformed the ZINB model in many simulation scenarios with combinations of zero-inflation and overdispersion, regardless of the sample size. In the empirical data analysis, we demonstrated that fitting incorrect models to overdispersed data leaded to incorrect regression coefficients estimates and overstated significance of some of the predictors. CONCLUSIONS: Based on this study, we recommend to the researchers that they consider the ZIP models for count data with zero-inflation only and NB models for overdispersed data or data with combinations of zero-inflation and overdispersion. If the researcher believes there are two different data generating mechanisms producing zeros, then the ZINB regression model may provide greater flexibility when modeling the zero-inflation and overdispersion.


Assuntos
Hospitais , Modelos Estatísticos , Distribuição Binomial , Humanos , Tempo de Internação , Distribuição de Poisson
19.
Stat Methods Med Res ; 31(11): 2237-2254, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35899309

RESUMO

Human microbiome research has become a hot-spot in health and medical research in the past decade due to the rapid development of modern high-throughput. Typical data in a microbiome study consisting of the operational taxonomic unit counts may have over-dispersion and/or structural zero issues. In such cases, negative binomial models can be applied to address the over-dispersion issue, while zero-inflated negative binomial models can be applied to address both issues. In practice, it is essential to know if there is zero-inflation in the data before applying negative binomial or zero-inflated negative binomial models because zero-inflated negative binomial models may be unnecessarily complex and difficult to interpret, or may even suffer from convergence issues if there is no zero-inflation in the data. On the other hand, negative binomial models may yield invalid inferences if the data does exhibit excessive zeros. In this paper, we develop a new test for detecting zero-inflation resulting from a latent class of subjects with structural zeros in a negative binomial regression model by directly comparing the amount of observed zeros with what would be expected under the negative binomial regression model. A closed form of the test statistic as well as its asymptotic properties are derived based on estimating equations. Intensive simulation studies are conducted to investigate the performance of the new test and compare it with the classical Wald, likelihood ratio, and score tests. The tests are also applied to human gut microbiome data to test latent class in microbial genera.


Assuntos
Microbioma Gastrointestinal , Humanos , Modelos Estatísticos , Simulação por Computador , Distribuição de Poisson
20.
AIDS Res Ther ; 19(1): 31, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761327

RESUMO

OBJECTIVE: This study investigated prevalence trends and identified the associated factors of HIV, syphilis and hepatitis C virus (HCV) among pregnant women in the Guangxi Zhuang Autonomous Region (Guangxi), Southwest China. METHODS: Serial cross-sectional surveys were performed annually among pregnant women in Guangxi from 2009 to 2018. Blood specimens were collected to test the prevalence of HIV, syphilis and HCV. Cochran-Armitage analysis was used to assess the trends of HIV, syphilis and HCV prevalence, as well as the sociodemographic and behavioural data. In this study, we used zero-inflated negative binomial (ZINB) regression models to identify factors associated with HIV, syphilis and HCV infection. RESULTS: A total of 23,879 pregnant women were included in the study. The prevalence of HIV, syphilis and HCV was 0.24%, 0.85% and 0.19%, respectively. There was a decrease in HIV prevalence from 0.54% to 0.10%, a decrease in HCV prevalence from 0.40% to 0.05% and a decrease in syphilis prevalence from 1.53% to 0.30%. The findings based on the ZINB model revealed that pregnant women who had a history of STI had significantly increased risks of HIV (OR 6.63; 95% CI 1.33-32.90) and syphilis (OR 9.06; 95% CI 3.85-21.30) infection, while pregnant women who were unmarried/widowed/divorced were more likely to have HIV (OR 2.81; 95% CI 1.20-6.54) and HCV (OR 58.12; 95% CI, 3.14-1076.99) infection. Furthermore, pregnant women whose husband had a history of STI (OR 5.62; 95% CI 1.24-25.38) or drug use (OR 7.36; 95% CI 1.25-43.43) showed an increased risk of HIV infection. CONCLUSIONS: There was a relatively low prevalence of HIV, syphilis and HCV among pregnant women. Although decreasing trends in HIV, syphilis and HCV infections were observed, effort is needed to promote STI testing in both premarital medical check-ups and antenatal care, especially targeting couples with a history of STI or drug use.


Assuntos
Infecções por HIV , Hepatite C , Profissionais do Sexo , Transtornos Relacionados ao Uso de Substâncias , Sífilis , China/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Hepacivirus , Hepatite C/epidemiologia , Humanos , Gravidez , Gestantes , Prevalência , Fatores de Risco , Sífilis/epidemiologia
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