Mixed-effects regression models for the analysis of clustered and longitudinal data
Application of item response theory and computerized adaptive testing to problems in mental health measurement
Problems in the analysis of high-dimensional datasets that are encountered in ecological momentary assessments, fMRI and microarray studies
Interval estimation including prediction, tolerance, and confidence intervals for environmental monitoring problems
CHS In the News
The Center for Health Statistics, and its numerous faculty members, frequently make headlines in the health sciences realm. Explore some of the latest blog posts and news articles from CHS faculty.
JAMA Psychiatry: Social Vulnerability and Prevalence and Treatment for Mental Health and Substance Use Disorders
Interview with Robert D. Gibbons, PhD, and Ronald C. Kessler, PhD, authors of Social Vulnerability and Prevalence and Treatment for Mental Health and Substance Use Disorders. Hosted by John Torous, MD, MBI.
READ MORESmithosonian Magazine: Can Technology Help Us More Accurately Diagnose Mental Illnesses?
A new wave of tools promises to offer quicker, more objective assessments to help patients and clinicians.
READ MOREUChicago: Study finds folic acid treatment is associated with decreased risk of suicide attempts
Suicide is one of the leading causes of death in the US, with more than 45,000 people dying by suicide in 2020. Experts recommend many strategies and treatments to decrease the risk of suicide, including psychotherapy, peer support, economic support, and medications like antidepressants. Few if any would be likely to put folic acid supplements on that list, but a recent study done at the University of Chicago may change that.
READ MOREA few things we’ve recently published…
The social vulnerability metric (SVM) as a new tool for public health
The SVM, developed by researchers at the University of Chicago and Johns Hopkins University, is a new an improved method of evaluating the social determinants of health. It uses ecological data at the ZIP code or county level to accurately identify prevalent social vulnerabilities within a community.
Saulsberry L., Bhargava A., Zeng S., Gibbons J., Brannan C., Lauderdale D., Gibbons R.D.
A Prospective Examination of the Predictive Validity of Three Transdiagnostic Assessments of Risk for Suicidal Behavior: Psychache, the Interpersonal Theory of Suicide, and Reasons for Living
To assess the predictive validity (PV) of Psychache, the Interpersonal Theory of Suicide (IPTS), and Reasons for Living (RFL) regarding future suicide attempts (SA) in youth.
Paul, B. T., Greeno, C., Ryan, N. D., Tsui, F. R., Gibbons, R. D., Porta, G., Joiner, T., & Brent, D.
Fiducial inference for random-effects calibration models: Advancing reliable quantification in environmental analytical chemistry
This article addresses calibration challenges in analytical chemistry by employing a random-effects calibration curve model and its generalizations to capture variability in analyte concentrations. The model is motivated by specific issues in analytical chemistry, where measurement errors remain constant at low concentrations but increase proportionally as concentrations rise.
Sahu S., Mathew T., Gibbons R.D., Bhaumik D. K.
Sparse Bayesian Multidimensional Item Response Theory
Multivariate Item Response Theory (MIRT) is sought-after widely by applied researchers looking for interpretable (sparse) explanations underlying response patterns in questionnaire data. There is, however, an unmet demand for such sparsity discovery tools in practice. Our paper develops a Bayesian platform for binary and ordinal item MIRT which requires minimal tuning and scales well on large datasets due to its parallelizable features.
Li J., Gibbons R.D., Rockova V.
Parental Diseases of Despair and Suicidal Events in Their Children
Suicide and suicidal behavior among US adolescents has increased dramatically over the past 2 decades, without a clear explanation. Deaths of despair in midlife adults, due to suicide, alcohol-related disease, or drug overdose, have doubled in the past decade, with parallel increases in corresponding diseases of despair (DoD), indicating that there could be an association between these 2 epidemics.
Brent D.A., Hur K., Gibbons J.B., Porta G., Gibbons R.D.
A National Study Among Diverse US Populations of Exposure to Prescription Medications with Evidence-Based Pharmacogenomic Information
Tailoring pharmacogenomic (PGx) implementation to diverse populations is vital to promoting health equity. We assessed prescriptions for medications with potentially actionable PGx information to identify patient characteristics associated with differential PGx medication exposure. We analyzed the nationally-representative MEPS dataset of adults who reported receiving prescriptions between 2014 and 2021.
Saulsberry, L., Jameson, J. C., Gibbons, R. D., Dolan, M. E., Olopade, O. I., & O’Donnell, P. H.
Notable Publications
The MTA at 8 years: prospective follow-up of children treated for combined-type ADHD in a multisite study
To determine any long-term effects, 6 and 8 years after childhood enrollment, of the randomly assigned 14-month treatments in the Multimodal Treatment Study of Children with ADHD (MTA; N=436); to test whether ADHD symptom trajectory through 3-years predicts outcome in subsequent years; to examine functioning level of the MTA adolescents relative to their non-ADHD peers,
Read moreWithout Wasting a Word: Extreme Improvements in Efficiency and Accuracy Using Computerized Adaptive Testing for Mental Health Disorders (CAT-MH)
Adaptive tests for a wide variety of mental health traits have been validated in a variety of settings against lengthy structured clinical interviews with excellent results and even higher reliability than fixed-length tests. Applications include screening and assessments in emergency departments, psychiatric and primary care clinics, student health clinics, perinatal medicine clinics, child welfare settings, and the judicial system. The future of mental health measurement will be based on automated screening and assessments.
Read moreDevelopment of a Computerized Adaptive Test for Depression
Unlike other areas of medicine, psychiatry is almost entirely dependent on patient report to assess the presence and severity of disease; therefore, it is particularly crucial that we find both more accurate and efficient means of obtaining that report. Traditional measurement fixes the number of items administered and allows measurement uncertainty to vary. In contrast, a CAT fixes measurement uncertainty and allows the number of items to vary. The result is a significant reduction in the number of items needed to measure depression and increased precision of measurement.
Read moreAdvances in analysis of longitudinal data
In this review, we explore recent developments in the area of linear and nonlinear generalized mixed-effects regression models and various alternatives, including generalized estimating equations for analysis of longitudinal data. Methods are described for continuous and normally distributed as well as categorical (binary, ordinal, nominal) and count (Poisson) variables. Extensions of the model to three and four levels of clustering, multivariate outcomes, and incorporation of design weights are also described. Linear and nonlinear models are illustrated using an example involving a study of the relationship between mood and smoking.
Read moreHarvard Data Science Review: A Global Forum on Everything Data Science
As an open access platform of the Harvard Data Science Initiative, Harvard Data Science Review (HDSR) features foundational thinking, research milestones, educational innovations, and major applications. It aims to publish contents that help to define and shape data science as a scientifically rigorous and globally impactful multidisciplinary field based on the principled and purposed production, processing, parsing and analysis of data.
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Dr. Robert Gibbons co-authors new book on Item Response Theory with Dr. Darrell Bock
In Item Response Theory, accomplished psychometricians Darrell Bock and Robert Gibbons deliver a comprehensive and up-to-date exploration of the theoretical foundations and applications of Item Response Theory (IRT). Covering both unidimensional and multidimensional IRT, as well as related adaptive test administration of previously calibrated item banks, the book addresses the growing need for understanding of this topic as the use of IRT spreads to other fields.
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The Committee on Quantitative Methods in Social, Behavioral, and Health Sciences
This is an interdisciplinary community of faculty and students interested in methodological research in relation to applications in social, behavioral, and health sciences.
LEARN MOREFeatured Tool: SuperMix
SuperMix combines the functionality of four mixed-effects programs, MIXREG, MIXOR, MIXNO, and MIXPREG, developed by Donald Hedeker and Robert Gibbons into a single application to provide estimates for mixed-effects regression models.
SuperMix has been developed by SSI under an SBIR Phase II contract N44MH32056. SuperMix will fit models with continuous, count, ordinal, nominal, and survival outcome variables with nested data, allowing for up to three levels of nesting.
MIXED-EFFECTS MODELING
Mixed-effects models are also known as multilevel, hierarchical, or random-effects models. These models can be used for the analysis of longitudinal data, where each individual may be measured at a different number of occasions. They can also be used for clustered data, such as for patients within clinics.
FREE STUDENT EDITION
A student version of SuperMix for Windows can be downloaded from SSI: Scientific Software International.
LEARN MOREThe Statistics of CHS
We offer a rich statistical talent that is rarely found in a single department, let alone a center. Under the direction of Professor Robert D. Gibbons, the Center quickly grew to include a faculty of 32 members both from the University of Chicago and in collaboration with other Universities.