Improving the stability of bivariate correlations using informative Bayesian priors: a Monte Carlo simulation study

ObjectiveMuch of psychological research has suffered from small sample sizes and low statistical power, resulting in unstable parameter estimates. The Bayesian approach offers a promising solution by incorporating prior knowledge into statistical models, which may lead to improved stability compared to a frequentist approach.MethodsSimulated data from four populations with known bivariate correlations (ρ = 0.1, 0.2, 0.3, 0.4) was used to estimate the sample correlation as samples were sequentially added from the population, from n = 10 to n = 500. The impact of three different, subjectively defined prior distributions (weakly, moderately, and highly informative) was investigated and compared to a frequentist model.ResultsThe results show that bivariate correlation estimates are unstable, and that the risk of obtaining an estimate that is exaggerated or in the wrong direction is relatively high, for sample sizes for below 100, and considerably so for sample sizes below 50. However, this instability can be constrained by informative Bayesian priors.ConclusionInformative Bayesian priors have the potential to significantly reduce sample size requirements and help ensure that obtained estimates are in line with realistic expectations. The combined stabilizing and regularizing effect of a weakly informative prior is particularly useful when conducting research with small samples. The impact of more informative Bayesian priors depends on one’s threshold for probability and whether one’s goal is to obtain an estimate merely in the correct direction, or to obtain a high precision estimate whose associated interval falls within a narrow range. Implications for sample size requirements and directions for future research are discussed

Offenders in emerging adulthood : School maladjustment, childhood adversities, and prediction of aggressive antisocial behaviors

Early psychosocial adversities and maladjustment, such as childhood maltreatment and school adjustment problems, have been linked to an increased risk of aggressive antisocial behaviors. Yet, clinical studies of subjects at the highest risk of persistence in such behaviors are rare, especially during the life-changing transition years of emerging adulthood. This study describes early predictors of aggressive antisocial behaviors in a large, nationally representative cohort of Swedish, male violent offenders in emerging adulthood (age range = 18-25 years; N = 270). First, data on psychosocial background characteristics and aggressive antisocial behaviors (including age at onset) are provided. Second, early predictors of aggressive antisocial behaviors are tested in bivariate and multivariate interactive models. The offenders demonstrated a diversity of early onset adversities and disruptive behaviors, in line with established risk factors for subsequent criminality and adverse outcomes in a variety of life domains. Severe school adjustment problems, especially bullying others and early onset truancy, were important and interrelated predictors of aggressive antisocial behaviors over the lifetime, whereas childhood adversities such as parental substance or alcohol abuse and repeated exposure to violence at home during childhood were interrelated predictors of aggressive antisocial behaviors, albeit with less statistical importance. The findings stress the importance of early identification of individuals in the risk zone of developing severe and persistent aggressive antisocial behaviors and of early preventive interventions directed toward families with high-risk profiles. The findings also provide initial guidelines on which psychosocial background risk factors that need to be considered first-hand in early interventions. (PsycINFO Database Recor

Pinpointing change in virtual reality assisted treatment for violent offenders: a pilot study of Virtual Reality Aggression Prevention Training (VRAPT)

Preventing relapse into violence and its destructive consequences among persistent re-offenders is a primary concern in forensic settings. The Risk-Need-Responsivity framework models the best current practice for offender treatment, focused on building skills and changing pro-criminal cognitions. However, treatment effects are often modest, and the forensic context can obstruct the delivery of interventions. Developing treatments for offenders should focus on the best method of delivery to make “what works work.” Virtual reality (VR)-assisted treatments such as Virtual Reality Aggression Prevention Training (VRAPT) are a new and innovative approach to offender treatment. This pilot study followed 14 male violent offenders who participated in VRAPT in a Swedish prison context and measured changes from pre-treatment to post-treatment and 3-month follow-up in targeted aggression, emotion regulation, and anger. It also investigated potential impact factors (pro-criminal cognitions, externalizing behaviors, psychosocial background, and childhood adverse experiences). In Bayesian linear mixed effects models, participants showed a high probability of change from pre-treatment to post-treatment and to follow-up on all outcome measures. All outcome measures demonstrated a low probability of change from post-treatment to follow-up. Analysis of reliable change showed that participants’ results ranged from recovery to deterioration. We discuss the implications of the study for VRAPT’s impact on the target group, those who might benefit from the approach, and suggested foci for future studies in the field of VR-assisted offender treatment. The study was preregistered at the International Standard Randomized Controlled Trial Number registry (https://doi.org/10.1186/ISRCTN14916410)

A Federated Database for Obesity Research:An IMI-SOPHIA Study

Obesity is considered by many as a lifestyle choice rather than a chronic progressive disease. The Innovative Medicines Initiative (IMI) SOPHIA (Stratification of Obesity Phenotypes to Optimize Future Obesity Therapy) project is part of a momentum shift aiming to provide better tools for the stratification of people with obesity according to disease risk and treatment response. One of the challenges to achieving these goals is that many clinical cohorts are siloed, limiting the potential of combined data for biomarker discovery. In SOPHIA, we have addressed this challenge by setting up a federated database building on open-source DataSHIELD technology. The database currently federates 16 cohorts that are accessible via a central gateway. The database is multi-modal, including research studies, clinical trials, and routine health data, and is accessed using the R statistical programming environment where statistical and machine learning analyses can be performed at a distance without any disclosure of patient-level data. We demonstrate the use of the database by providing a proof-of-concept analysis, performing a federated linear model of BMI and systolic blood pressure, pooling all data from 16 studies virtually without any analyst seeing individual patient-level data. This analysis provided similar point estimates compared to a meta-analysis of the 16 individual studies. Our approach provides a benchmark for reproducible, safe federated analyses across multiple study types provided by multiple stakeholders.</p

A Critique on the Use of Statistical Inference in Criminological Research

The comprehensive over-representation of quantitative methods in criminological research is discussed in relation to the frequent misinterpretations of statistical results and methods. The study leads off with an introduction to essential probability theory together with a historical review of the rise of probability theory and statistics. A number of criminological articles are then examined with respect to their application and interpretation of statistical method and results. A concluding section summarizes the results and offers suggestions for solutions. Metaphysical considerations are discussed cursively throughout the text. Den omfattande överrepresentationen av kvantitativa metoder i kriminologisk forskning diskuteras i relation till den frekventa feltolkningen av statistiska resultat och metoder. Studien inleds med en introduktion till grundläggande sannolikhetslära tillsammans med en historisk redogörelse över sannolikhetslärans samt statistikens framväxt. Ett antal kriminologiska artiklar granskas sedan utifrån deras tillämpning och tolkning av statistisk metod och resultat. Ett avslutande avsnitt sammanfattar resultaten och erbjuder förslag på lösningar. Metafysiska antaganden diskuteras kursivt genom texten.

The neural basis of aberrant salience attribution in unmedicated patients with schizophrenia spectrum disorders

Due to abnormal functioning of the brain’s reward and prediction system patients with schizophrenia spectrum disorders are thought to assign salience to non-relevant objects and events and to form context-inappropriate associations. The brain’s ventral striatum is critical in the formation of associations, and aberrant associations are believed to create delusional content during psychosis. The study wanted to examine the neural response, particularly in the ventral striatum, combined with subjective reports as patients learn associations in an aversive Pavlovian conditioning paradigm. The stimuli were randomized and involved circles of different colors. The conditioned stimuli (CS+) was followed by an unconditioned stimuli (US), consisting of an unpleasant sound, in 50% of events. The unconditioned (CS-) stimuli was followed by a low, not unpleasant sound in 50% of events. The degree of striatal activation was thought to be associated with the severity of patient’s illness. Functional magnetic resonance imaging (fMRI) blood-oxygen-level dependent (BOLD) responses were examined in eleven unmedicated non-institutionalized patients with schizophrenia spectrum disorders and 15 matched healthy controls. No significant within group differences in neural or subjective response to the [CS+ &gt; CS-] contrast were found. No significant associations between severity of illness and degree of striatal activation in response to CS+ or CS- were found. Significant differences in neural activation for the [CS+ &gt; CS-] contrast were found in the ventral striatum, the right inferor frontal gyrus, and the right angular gyrus, with patients exhibiting stronger activation compared to controls. The results and implications are discussed along with suggestions for future research

A Critique on the Use of Statistical Inference in Criminological Research

The comprehensive over-representation of quantitative methods in criminological research is discussed in relation to the frequent misinterpretations of statistical results and methods. The study leads off with an introduction to essential probability theory together with a historical review of the rise of probability theory and statistics. A number of criminological articles are then examined with respect to their application and interpretation of statistical method and results. A concluding section summarizes the results and offers suggestions for solutions. Metaphysical considerations are discussed cursively throughout the text. Den omfattande överrepresentationen av kvantitativa metoder i kriminologisk forskning diskuteras i relation till den frekventa feltolkningen av statistiska resultat och metoder. Studien inleds med en introduktion till grundläggande sannolikhetslära tillsammans med en historisk redogörelse över sannolikhetslärans samt statistikens framväxt. Ett antal kriminologiska artiklar granskas sedan utifrån deras tillämpning och tolkning av statistisk metod och resultat. Ett avslutande avsnitt sammanfattar resultaten och erbjuder förslag på lösningar. Metafysiska antaganden diskuteras kursivt genom texten.

Structural Brain Correlates of the Externalizing Spectrum in Young Adults

The externalizing spectrum, including traits and behaviors such as aggression, reduced inhibitiory control and substance abuse, is associated with altered prefrontal brain morphology. However, the degree to which different manifestations of the externalizing spectrum are associated with distinct or overlapping variations in individual brain morphology is unclear. Here, we therefore used structural magnetic resonance imaging, self-report assessment, and a response inhibition task in a sample of 59 young adults to examine how cortical thickness in the anterior cingulate cortex (ACC), orbitofrontal cortex (OFC), and dorsolateral prefrontal cortex (DLPFC) relate to four different manifestations of the externalizing spectrum: disinhibition, callous aggression, substance abuse, and behavioral inhibitory control. Using Bayesian linear regression models controlling for age, gender, and years of education, we found that the different manifestations of the externalizing spectrum were associated with both distinct and overlapping morphology variations. Specifically, both callous aggression and inhibitory control was associated with increased cortical thickness of the OFC, a region involved in reward processing, decision-making, and regulation of anxiety and fear. Both disinhibition and substance abuse were associated with DLPFC thickness, although with opposite association patterns, possibly reflecting processes related to inhibitory control, working memory and attention. Moreover, disinhibition, but not callous aggression or substance abuse, was associated with behavioral inhibitory control. Our results provide further support for the link between externalizing behaviors and prefrontal brain morphology, while identifying distinct prefrontal areas associated with different clinically relevant manifestations. These findings may help guide further research aimed at developing novel treatment and intervention strategies for externalizing behaviors and disorders