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1.
Multivariate Behav Res ; 59(3): 502-522, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38348679

RESUMO

In psychology and education, tests (e.g., reading tests) and self-reports (e.g., clinical questionnaires) generate counts, but corresponding Item Response Theory (IRT) methods are underdeveloped compared to binary data. Recent advances include the Two-Parameter Conway-Maxwell-Poisson model (2PCMPM), generalizing Rasch's Poisson Counts Model, with item-specific difficulty, discrimination, and dispersion parameters. Explaining differences in model parameters informs item construction and selection but has received little attention. We introduce two 2PCMPM-based explanatory count IRT models: The Distributional Regression Test Model for item covariates, and the Count Latent Regression Model for (categorical) person covariates. Estimation methods are provided and satisfactory statistical properties are observed in simulations. Two examples illustrate how the models help understand tests and underlying constructs.


Assuntos
Modelos Estatísticos , Humanos , Análise de Regressão , Reprodutibilidade dos Testes , Simulação por Computador/estatística & dados numéricos , Distribuição de Poisson , Psicometria/métodos , Interpretação Estatística de Dados
2.
Behav Res Methods ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195788

RESUMO

A new algorithm to identify a representative scanpath in a sample is presented and evaluated with eye-tracking data. According to Gestalt theory, each fixation of the scanpath should be on an area of interest (AOI) of the stimuli. As with existing methods, we first identify the AOIs and then extract the fixations of the representative scanpath from the AOIs. In contrast to existing methods, we propose a new concept of short-time AOI and extract the fixations of representative scanpath from the short-time AOIs. Our method outperforms the existing methods on two publicly available datasets. Our method can be applied to arbitrary visual stimuli, including static stimuli without natural segmentation, as well as dynamic stimuli. Our method also provides a solution for issues caused by the selection of scanpath similarity.

3.
J Med Internet Res ; 25: e46771, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37358893

RESUMO

BACKGROUND: Suicide is a global public health problem. Digital interventions are considered a low-threshold treatment option for people with suicidal ideation or behaviors. Internet-based cognitive behavioral therapy (iCBT) targeting suicidal ideation has demonstrated effectiveness in reducing suicidal ideation. However, suicidal ideation often is related to additional mental health problems, which should be addressed for optimal care. Yet, the effects of iCBT on related symptoms, such as depression, anxiety, and hopelessness, remain unclear. OBJECTIVE: We aimed to analyze whether digital interventions targeting suicidal ideation had an effect on related mental health symptoms (depression, anxiety, and hopelessness). METHODS: We systematically searched CENTRAL, PsycInfo, Embase, and PubMed for randomized controlled trials that investigated guided or unguided iCBT for suicidal ideation or behaviors. Participants reporting baseline suicidal ideation were eligible. Individual participant data (IPD) were collected from eligible trials. We conducted a 1-stage IPD meta-analysis on the effects on depression, anxiety, and hopelessness-analyzed as 2 indices: symptom severity and treatment response. RESULTS: We included IPD from 8 out of 9 eligible trials comprising 1980 participants with suicidal ideation. iCBT was associated with significant reductions in depression severity (b=-0.17; 95% CI -0.25 to -0.09; P<.001) and higher treatment response (ie, 50% reduction of depressive symptoms; b=0.36; 95% CI 0.12-0.60; P=.008) after treatment. We did not find significant effects on anxiety and hopelessness. CONCLUSIONS: iCBT for people with suicidal ideation revealed significant effects on depression outcomes but only minor or no effects on anxiety and hopelessness. Therefore, individuals with comorbid symptoms of anxiety or hopelessness may require additional treatment components to optimize care. Studies that monitor symptoms with higher temporal resolution and consider a broader spectrum of factors influencing suicidal ideation are needed to understand the complex interaction of suicidality and related mental health symptoms.


Assuntos
Terapia Cognitivo-Comportamental , Depressão , Humanos , Depressão/terapia , Ideação Suicida , Ansiedade/terapia , Internet
4.
BMC Cancer ; 22(1): 634, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35681127

RESUMO

BACKGROUND: Breast cancer (BC) is the most frequently diagnosed cancer among women. Numerous studies explored cell-free circulating microRNAs as diagnostic biomarkers of BC. As inconsistent and rarely intersecting microRNA panels have been reported thus far, we aim to evaluate the overall diagnostic performance as well as the sources of heterogeneity between studies. METHODS: Based on the search of three online search engines performed up to March 21st 2022, 56 eligible publications that investigated diagnostic circulating microRNAs by utilizing Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) were obtained. Primary studies' potential for bias was evaluated with the revised tool for the quality assessment of diagnostic accuracy studies (QUADAS-2). A bivariate generalized linear mixed-effects model was applied to obtain pooled sensitivity and specificity. A novel methodology was utilized in which the sample and study models' characteristics were analysed to determine the potential preference of studies for sensitivity or specificity. RESULTS: Pooled sensitivity and specificity of 0.85 [0.81-0.88] and 0.83 [0.79-0.87] were obtained, respectively. Subgroup analysis showed a significantly better performance of multiple (sensitivity: 0.90 [0.86-0.93]; specificity: 0.86 [0.80-0.90]) vs single (sensitivity: 0.82 [0.77-0.86], specificity: 0.83 [0.78-0.87]) microRNA panels and a comparable pooled diagnostic performance between studies using serum (sensitivity: 0.87 [0.81-0.91]; specificity: 0.83 [0.78-0.87]) and plasma (sensitivity: 0.83 [0.77-0.87]; specificity: 0.85 [0.78-0.91]) as specimen type. In addition, based on bivariate and univariate analyses, miRNA(s) based on endogenous normalizers tend to have a higher diagnostic performance than miRNA(s) based on exogenous ones. Moreover, a slight tendency of studies to prefer specificity over sensitivity was observed. CONCLUSIONS: In this study the diagnostic ability of circulating microRNAs to diagnose BC was reaffirmed. Nonetheless, some subgroup analyses showed between-study heterogeneity. Finally, lack of standardization and of result reproducibility remain the biggest issues regarding the diagnostic application of circulating cell-free microRNAs.


Assuntos
Neoplasias da Mama , MicroRNA Circulante , MicroRNAs , Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Feminino , Humanos , MicroRNAs/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Multivariate Behav Res ; 57(1): 40-56, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32772593

RESUMO

What to do when item response data are multidimensional but a unidimensional model is preferred in terms of statistical simplicity and ease of interpretability? The projection method for the compensatory logistic multidimensional item response model for dichotomous data leads to a two parameter logistic model with local item dependence. Despite the local item dependence, the model is unidimensional for many practical purposes. Here, Ip's projection method is generalized to the case of the graded response model for polytomous variables, extending the applicability of the method to Likert-type response formats. A secondary aim of the paper is the study of rotation techniques intended for use prior to projection. In contrast to rotations aiming at a simple structure of factor loadings, the proposed techniques increase the variance explained before or after projection, facilitate the interpretation of the projected dimension by variants of target rotations or a mix of both. The method is illustrated with an application to the Highly Sensitive Person Scale and R code is provided.


Assuntos
Modelos Estatísticos , Humanos , Modelos Logísticos , Psicometria/métodos
6.
J Med Internet Res ; 23(6): e26385, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33999837

RESUMO

BACKGROUND: In the face of the COVID-19 pandemic, the German government and the 16 German federal states implemented a variety of nonpharmaceutical interventions (NPIs) to decelerate the spread of the SARS-CoV-2 virus and thus prevent a collapse of the health care system. These measures comprised, among others, social distancing, the temporary closure of shops and schools, and a ban of large public gatherings and meetings with people not living in the same household. OBJECTIVE: It is fair to assume that the issued NPIs have heavily affected social life and psychological functioning. We therefore aimed to examine possible effects of this lockdown in conjunction with daily new infections and the state of the national economy on people's interests, motives, and other psychological states. METHODS: We derived 249 keywords from the Google Trends database, tapping into 27 empirically and rationally selected psychological domains. To overcome issues with reliability and specificity of individual indicator variables, broad factors were derived by means of time series factor analysis. All domains were subjected to a change point analysis and time series regression analysis with infection rates, NPIs, and the state of the economy as predictors. All keywords and analyses were preregistered prior to analysis. RESULTS: With the pandemic arriving in Germany, significant increases in people's search interests were observed in virtually all domains. Although most of the changes were short-lasting, each had a distinguishable onset during the lockdown period. Regression analysis of the Google Trends data confirmed pronounced autoregressive effects for the investigated variables, while forecasting by means of the tested predictors (ie, daily new infections, NPIs, and the state of economy) was moderate at best. CONCLUSIONS: Our findings indicate that people's interests, motives, and psychological states are heavily affected in times of crisis and lockdown. Specifically, disease- and virus-related domains (eg, pandemic disease, symptoms) peaked early, whereas personal health strategies (eg, masks, homeschooling) peaked later during the lockdown. Domains addressing social life and psychosocial functioning showed long-term increases in public interest. Renovation was the only domain to show a decrease in search interest with the onset of the lockdown. As changes in search behavior are consistent over multiple domains, a Google Trends analysis may provide information for policy makers on how to adapt and develop intervention, information, and prevention strategies, especially when NPIs are in effect.


Assuntos
Pessoal Administrativo/psicologia , Esgotamento Psicológico/psicologia , COVID-19/psicologia , Conflito de Interesses , Mídias Sociais , Humanos , SARS-CoV-2/isolamento & purificação
7.
Behav Res Methods ; 53(6): 2650-2667, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34027596

RESUMO

This paper presents a model that allows group comparisons of gaze behavior while watching dynamic video stimuli. The model is based on the approach of Coutrot and Guyader (2017) and allows linear combinations of feature maps to form a master saliency map. The feature maps in the model are, for example, the dynamically salient contents of a video stimulus or predetermined areas of interest. The model takes into account temporal aspects of the stimuli, which is a crucial difference to other common models. The multi-group extension of the model introduced here allows to obtain relative importance plots, which visualize the effect of a specific feature of a stimulus on the attention and visual behavior for two or more experimental groups. These plots are interpretable summaries of data with high spatial and temporal resolution. This approach differs from many common methods for comparing gaze behavior between natural groups, which usually only include single-dimensional features such as the duration of fixation on a particular part of the stimulus. The method is illustrated by contrasting a sample of a group of persons with particularly high cognitive abilities (high achievement on IQ tests) with a control group on a psycholinguistic task on the conceptualization of motion events. In the example, we find no substantive differences in relative importance, but more exploratory gaze behavior in the highly gifted group. The code, videos, and eye-tracking data we used for this study are available online.


Assuntos
Tecnologia de Rastreamento Ocular , Fixação Ocular , Atenção , Movimentos Oculares , Humanos , Modelos Estatísticos
8.
Biom J ; 62(7): 1597-1630, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32510177

RESUMO

Pooling the relative risk (RR) across studies investigating rare events, for example, adverse events, via meta-analytical methods still presents a challenge to researchers. The main reason for this is the high probability of observing no events in treatment or control group or both, resulting in an undefined log RR (the basis of standard meta-analysis). Other technical challenges ensue, for example, the violation of normality assumptions, or bias due to exclusion of studies and application of continuity corrections, leading to poor performance of standard approaches. In the present simulation study, we compared three recently proposed alternative models (random-effects [RE] Poisson regression, RE zero-inflated Poisson [ZIP] regression, binomial regression) to the standard methods in conjunction with different continuity corrections and to different versions of beta-binomial regression. Based on our investigation of the models' performance in 162 different simulation settings informed by meta-analyses from the Cochrane database and distinguished by different underlying true effects, degrees of between-study heterogeneity, numbers of primary studies, group size ratios, and baseline risks, we recommend the use of the RE Poisson regression model. The beta-binomial model recommended by Kuss (2015) also performed well. Decent performance was also exhibited by the ZIP models, but they also had considerable convergence issues. We stress that these recommendations are only valid for meta-analyses with larger numbers of primary studies. All models are applied to data from two Cochrane reviews to illustrate differences between and issues of the models. Limitations as well as practical implications and recommendations are discussed; a flowchart summarizing recommendations is provided.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Modelos Estatísticos , Risco , Simulação por Computador , Humanos
9.
Clin Psychol Psychother ; 27(2): 193-202, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31881096

RESUMO

Ecological momentary assessment (EMA) has been shown to be a valid and sensitive measure of treatment effects in obsessive-compulsive disorder (OCD). As part of a clinical trial, this EMA study deals with a comparison of two treatment conditions, that is, cognitive restructuring (CR) and detached mindfulness (DM). EMA data from n = 39 OCD patients were available from a randomized clinical trial on the effectiveness of CR and DM. Smartphone-based EMA sampling spread over 4 days each before and after treatment, with 10 random prompts per day and a 2-week intervention of either CR or DM. We tracked CR strategies (e.g., questioning an appraisal by re-evaluating risk), DM strategies (e.g., allowing one's thoughts to come and go), and application of newly learned strategies during Post-Treatment EMA. Although there was a trend towards DM strategies being applied more often during Pre-Treatment EMA than CR strategies, we did not find differences during Post-Treatment EMA between CR and DM regarding frequency or difficulty of application and experienced relief. As expected, we found a clear pre-post increase for all CR and DM behaviours except for one DM item. However, we did not find a treatment-specific increase of CR and DM behaviours; that is, both interventions equally well promoted a seemingly general treatment effect. Despite the ecological validity of EMA, however, social desirability effects cannot be ruled out, so that this conclusion must be handled cautiously. Further research is needed to replicate and generalize our results.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Avaliação Momentânea Ecológica/estatística & dados numéricos , Atenção Plena/métodos , Transtorno Obsessivo-Compulsivo/psicologia , Transtorno Obsessivo-Compulsivo/terapia , Humanos , Resultado do Tratamento
10.
Clin Psychol Psychother ; 26(6): 695-706, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31365952

RESUMO

As part of a larger clinical trial, this ecological momentary assessment (EMA) study pursued the main goal of demonstrating that the EMA method is sensitive to treatment effects of detached mindfulness and cognitive restructuring for obsessive-compulsive disorder (OCD). A second goal was to provide a descriptive analysis of OCD symptoms and influencing factors in participants' everyday lives. Thirty-nine participants were included in the final analyses. EMA sampling involved a smartphone and comprised 4 days with 10 random prompts per day both before (Pre-Treatment EMA) and after the completion of a 2-week clinical intervention of either detached mindfulness or cognitive restructuring (Post-Treatment EMA) that participants had been randomly allocated to. The EMA questionnaire included items on the frequency of obsessions, subjective burden due to obsessions, perceived current stress, emotions, and on the frequency of compulsions and other dysfunctional behaviors. Descriptive Pre-Treatment EMA results highlight the importance of compulsions and emotional states of tension/discomfort in OCD. Pre-Post comparisons showed a significant reduction of avoidance behavior, obsessions, and burden due to obsessions, with a nonsignificant trend also indicating a reduction of compulsions. There was no pre to post effect concerning emotions. This study adds to the existing research on OCD symptoms and offers further evidence in confirmation of established theoretical models of OCD. Also, our results can be taken as evidence for treatment sensitivity of the EMA method in OCD. Further research is needed to replicate, broaden, and generalize our results.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Avaliação Momentânea Ecológica , Atenção Plena/métodos , Transtorno Obsessivo-Compulsivo/terapia , Adulto , Feminino , Humanos , Masculino , Inquéritos e Questionários , Resultado do Tratamento
11.
Br J Psychiatry ; 210(2): 96-104, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27908895

RESUMO

BACKGROUND: Childhood maltreatment has been discussed as a risk factor for the development and maintenance of depression. AIMS: To examine the relationship between childhood maltreatment and adult depression with regard to depression incidence, severity, age at onset, course of illness and treatment response. METHOD: We conducted meta-analyses of original articles reporting an association between childhood maltreatment and depression outcomes in adult populations. RESULTS: In total, 184 studies met inclusion criteria. Nearly half of patients with depression reported a history of childhood maltreatment. Maltreated individuals were 2.66 (95% CI 2.38-2.98) to 3.73 (95% CI 2.88-4.83) times more likely to develop depression in adulthood, had an earlier depression onset and were twice as likely to develop chronic or treatment-resistant depression. Depression severity was most prominently linked to childhood emotional maltreatment. CONCLUSIONS: Childhood maltreatment, especially emotional abuse and neglect, represents a risk factor for severe, early-onset, treatment-resistant depression with a chronic course.


Assuntos
Sobreviventes Adultos de Maus-Tratos Infantis , Transtorno Depressivo/etiologia , Adulto , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/terapia , Humanos
12.
Biom J ; 59(1): 25-40, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27243898

RESUMO

In scientific research, many hypotheses relate to the comparison of two independent groups. Usually, it is of interest to use a design (i.e., the allocation of sample sizes m and n for fixed N=m+n) that maximizes the power of the applied statistical test. It is known that the two-sample t-tests for homogeneous and heterogeneous variances may lose substantial power when variances are unequal but equally large samples are used. We demonstrate that this is not the case for the nonparametric Wilcoxon-Mann-Whitney-test, whose application in biometrical research fields is motivated by two examples from cancer research. We prove the optimality of the design m=n in case of symmetric and identically shaped distributions using normal approximations and show that this design generally offers power only negligibly lower than the optimal design for a wide range of distributions.


Assuntos
Pesquisa Biomédica/métodos , Biometria/métodos , Estatísticas não Paramétricas , Humanos , Modelos Estatísticos
13.
Clin Psychol Psychother ; 24(3): 697-711, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27561691

RESUMO

In order to test the predictions derived from emotional processing theory (EPT), this meta-analysis examined correlations between outcome of exposure therapy and three process variables: initial fear activation (IFA), within-session habituation (WSH) and between-session habituation (BSH). Literature search comprised a keyword-based search in databases, a reverse search and the examination of reference lists. Of the 21 studies included in the analyses, 17 provided data concerning IFA (57 endpoints, total N = 490), five concerning WSH (7 endpoints, total N = 116) and eight concerning BSH (22 endpoints, total N = 304). Owing to this data structure, analyses were performed using robust variance estimation with random-effects models being assumed a priori. Results indicated that WSH and BSH are positively related to treatment outcome. By contrast, the statistical association between IFA and outcome of exposure was not confirmed, whereas our moderator analysis suggested that physiological process measures lead to higher correlations than non-physiological ones. The results for IFA and BSH were affected by selective reporting. In sum, our results do not specifically strengthen EPT while matching other theoretical perspectives such as inhibitory learning and reality testing. Further research is needed to provide recommendations concerning the best way of delivering exposure therapy. Copyright © 2016 John Wiley & Sons, Ltd. KEY PRACTITIONER MESSAGE: This meta-analysis examined three variables of emotional processing theory (EPT). Initial fear activation was not linearly related to outcomes of exposure therapy. Habituation within and between sessions were shown to correlate with outcome. Outcome reporting bias was shown to play a crucial role in this meta-analysis. Results do not specifically support EPT.


Assuntos
Medo/psicologia , Habituação Psicofisiológica , Terapia Implosiva/métodos , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , Avaliação de Processos e Resultados em Cuidados de Saúde/métodos , Emoções , Humanos , Avaliação de Processos e Resultados em Cuidados de Saúde/estatística & dados numéricos
14.
Neuroimage ; 108: 182-93, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25536495

RESUMO

Is there one optimal topology of functional brain networks at rest from which our cognitive performance would profit? Previous studies suggest that functional integration of resting state brain networks is an important biomarker for cognitive performance. However, it is still unknown whether higher network integration is an unspecific predictor for good cognitive performance or, alternatively, whether specific network organization during rest predicts only specific cognitive abilities. Here, we investigated the relationship between network integration at rest and cognitive performance using two tasks that measured different aspects of working memory; one task assessed visual-spatial and the other numerical working memory. Network clustering, modularity and efficiency were computed to capture network integration on different levels of network organization, and to statistically compare their correlations with the performance in each working memory test. The results revealed that each working memory aspect profits from a different resting state topology, and the tests showed significantly different correlations with each of the measures of network integration. While higher global network integration and modularity predicted significantly better performance in visual-spatial working memory, both measures showed no significant correlation with numerical working memory performance. In contrast, numerical working memory was superior in subjects with highly clustered brain networks, predominantly in the intraparietal sulcus, a core brain region of the working memory network. Our findings suggest that a specific balance between local and global functional integration of resting state brain networks facilitates special aspects of cognitive performance. In the context of working memory, while visual-spatial performance is facilitated by globally integrated functional resting state brain networks, numerical working memory profits from increased capacities for local processing, especially in brain regions involved in working memory performance.


Assuntos
Encéfalo/fisiologia , Memória de Curto Prazo/fisiologia , Rede Nervosa/fisiologia , Adulto , Biomarcadores , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
15.
Behav Res Methods ; 47(2): 384-94, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24878597

RESUMO

The present article introduces the multivariate Elo-type algorithm (META), which is inspired by the Elo rating system, a tool for the measurement of the performance of chess players. The META is intended for adaptive experiments with correlated traits. The relationship of the META to other existing procedures is explained, and useful variants and modifications are discussed. The META was investigated within three simulation studies. The gain in efficiency of the univariate Elo-type algorithm was compared to standard univariate procedures; the impact of using correlational information in the META was quantified; and the adaptability to learning and fatigue was investigated. Our results show that the META is a powerful tool to efficiently control task performance in a short time period and to assess correlated traits. The R code of the simulations, the implementation of the META in MATLAB, and an example of how to use the META in the context of neuroscience are provided in supplemental materials.


Assuntos
Análise e Desempenho de Tarefas , Algoritmos , Simulação por Computador , Humanos , Desempenho Psicomotor , Projetos de Pesquisa , Fatores de Tempo
16.
Stat Med ; 33(18): 3061-77, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24753050

RESUMO

The present study investigates the performance of several statistical tests to detect publication bias in diagnostic meta-analysis by means of simulation. While bivariate models should be used to pool data from primary studies in diagnostic meta-analysis, univariate measures of diagnostic accuracy are preferable for the purpose of detecting publication bias. In contrast to earlier research, which focused solely on the diagnostic odds ratio or its logarithm ( ln ω), the tests are combined with four different univariate measures of diagnostic accuracy. For each combination of test and univariate measure, both type I error rate and statistical power are examined under diverse conditions. The results indicate that tests based on linear regression or rank correlation cannot be recommended in diagnostic meta-analysis, because type I error rates are either inflated or power is too low, irrespective of the applied univariate measure. In contrast, the combination of trim and fill and ln ω has non-inflated or only slightly inflated type I error rates and medium to high power, even under extreme circumstances (at least when the number of studies per meta-analysis is large enough). Therefore, we recommend the application of trim and fill combined with ln ω to detect funnel plot asymmetry in diagnostic meta-analysis.


Assuntos
Diagnóstico , Metanálise como Assunto , Viés de Publicação/estatística & dados numéricos , Bioestatística , Simulação por Computador , Humanos , Modelos Estatísticos , Razão de Chances , Análise de Regressão
17.
Psychol Methods ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483524

RESUMO

Individual differences are studied with a multitude of test instruments. Meta-analysis of tests is useful to understand whether individual differences in certain populations can be detected with the help of a class of tests. A method for the quantitative meta-analytical evaluation of test instruments with dichotomous items is introduced. The method assumes beta-binomially distributed test scores, an assumption that has been demonstrated to be plausible in many settings. With this assumption, the method only requires sample means and standard deviations of sum scores (or equivalently means and standard deviations of percent-correct scores), in contrast to methods that use estimates of reliability for a similar purpose. Two parameters are estimated for each sample: mean difficulty and an overdispersion parameter which can be interpreted as the test's ability to detect individual differences. The proposed bivariate meta-analytical approach (random or fixed effects) pools the two parameters simultaneously and allows to perform meta-regression. The bivariate pooling yields a between-sample correlation of mean difficulty parameters and overdispersion parameters. As a side product, reliability estimates are obtained which can be employed to disattenuate correlation coefficients for insufficient reliability when no other estimates are available. A worked example illustrates the method and R code is provided. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

18.
Front Psychiatry ; 15: 1266383, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745780

RESUMO

Studies using observational measures often fail to meet statistical standards for both reliability and validity. The present study examined the psychometric properties of the Coding Interactive Behavior (CIB) System within a German sample of parent-child dyads. The sample consisted of 149 parents with and without a mental illness and their children [n experimental group (EG) = 75, n control group (CG) = 74] who participated in the larger Children of Mentally Ill Parents at Risk Evaluation (COMPARE) study. The age of the children ranged from 3 to 12 years (M = 7.99, SD = 2.5). Exploratory factor analysis supported a five-factor model of the CIB with items describing 1) parental sensitivity/reciprocity, 2) parental intrusiveness, 3) child withdrawal, 4) child involvement, and 5) parent limit setting/child compliance. Compared to international samples, the model was reduced by two independent dyadic factors. Testing for predictive validity identified seven items with predictive power to differentiate parental group membership. The CIB factors did not seem to be sufficiently sensitive to illustrate differences in interaction within a sample of parents with various mental illnesses. To apply the CIB to the described sample or similar ones in the future, additional measurement instruments may be necessary.

19.
Psychol Methods ; 28(2): 422-437, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35588077

RESUMO

Regression models with interaction terms are common models for moderating relationships. When effects of several predictors from one group-for example, genetic variables-are potentially moderated by several predictors from another-for example, environmental variables-many interaction terms result. This complicates model interpretation, especially when coefficient signs point in different directions. By first forming a score for each group of predictors, the interaction model's dimension is severely reduced. The hierarchical score model is an elegant one-step approach: Score weights and regression model coefficients are estimated simultaneously by an alternating optimization (AO) algorithm. Especially in high dimensional settings, scores remain an effective technique to reduce interaction model dimension, and we propose regularization to ensure sparsity and interpretability of the score weights. A nontrivial extension of the original AO algorithm is presented, which adds a lasso penalty, resulting in the alternating lasso optimization algorithm (ALOA). The hierarchical score model with ALOA is an interpretable statistical learning technique for moderation in potentially high dimensional applications, and encompasses generalized linear models for the main interaction model. In addition to the lasso regularization, a screening procedure called regularization and residualization (RR) is proposed to avoid spurious interactions. ALOA tuning parameter choice and the RR screening procedure are investigated by simulations, and two illustrative applications to depression risk are provided. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Algoritmos , Humanos , Modelos Lineares
20.
J Clin Med ; 12(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37109142

RESUMO

Anastomotic leakage (AL) after colorectal resections is a serious complication in abdominal surgery. Especially in patients with Crohn's disease (CD), devastating courses are observed. Various risk factors for the failure of anastomotic healing have been identified; however, whether CD itself is independently associated with anastomotic complications still remains to be validated. A retrospective analysis of a single-institution inflammatory bowel disease (IBD) database was conducted. Only patients with elective surgery and ileocolic anastomoses were included. Patients with emergency surgery, more than one anastomosis, or protective ileostomies were excluded. For the investigation of the effect of CD on AL 141, patients with CD-type L1, B1-3 were compared to 141 patients with ileocolic anastomoses for other indications. Univariate statistics and multivariate analysis with logistic regression and backward stepwise elimination were performed. CD patients had a non-significant higher percentage of AL compared to non-IBD patients (12% vs. 5%, p = 0.053); although, the two samples differed in terms of age, body mass index (BMI), Charlson comorbidity index (CCI), and other clinical variables. However, Akaike information criterion (AIC)-based stepwise logistic regression identified CD as a factor for impaired anastomotic healing (final model: p = 0.027, OR: 17.043, CI: 1.703-257.992). Additionally, a CCI ≥ 2 (p = 0.010) and abscesses (p = 0.038) increased the disease risk. The alternative point estimate for CD as a risk factor for AL based on propensity score weighting also resulted in an increased risk, albeit lower (p = 0.005, OR 7.36, CI 1.82-29.71). CD might bear a disease-specific risk for the impaired healing of ileocolic anastomoses. CD patients are prone to postoperative complications, even in absence of other risk factors, and might benefit from treatment in dedicated centers.

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