About
Who we are
About VPG Health
Building on nearly two decades of COA experience, VPG Health stands as a leader in patient-centered outcomes research. VPG Health provides research services aimed at accumulating evidence to evaluate and support COAs as clinical trial endpoints. These services include literature/landscape assessments, the development and execution of qualitative research studies, the development and execution of psychometric studies, state-of-the-art eCOA services, and COA-based regulatory advice and services.
Leadership
R.J. Wirth,
PhD
R.J. Wirth is Chief Executive Officer, co-Founder, Consulting Psychometrician, and a Manager Partner at VPG. Dr. Wirth received his PhD in Quantitative Psychology from the historic LL Thurstone Psychometric Laboratory at University of North Carolina – Chapel Hill.
R.J. Wirth is Chief Executive Officer, co-Founder, Consulting Psychometrician, and a Manager Partner at VPG. Dr. Wirth received his PhD in Quantitative Psychology from the historic LL Thurstone Psychometric Laboratory at University of North Carolina – Chapel Hill.
Prior to leading VPG, Dr. Wirth held research positions at the Frank Porter Graham Child Development Institute at The University of North Carolina and in the School of Medicine at the University of Washington. For nearly two decades, Dr. Wirth has collaborated widely within the pharmaceutical and medical device industries to develop and/or evaluate the measurement properties of clinical outcome assessments and was awarded (as co-PI) one of the first FDA-funded CDER pilot program grants: Standard core clinical outcome assessments and their related endpoints.
Dr. Wirth has authored numerous peer-reviewed publications on such topics as item factor analysis, structural equation modeling, validity, as well as various aspects of scale development appearing in outlets such as Headache, Health Psychology, Medical Care, Psychological Assessment, Psychological Methods, and Quality of Life Research. He has participated as an invited expert speaker on multiple FDA panels and industry advisory boards focused on COA development and support. Dr. Wirth has authored numerous peer-reviewed publications on such topics as item factor analysis, structural equation modeling, validity, as well as various aspects of scale development appearing in outlets such as Headache, Health Psychology, Medical Care, Psychological Assessment, Psychological Methods and Quality of Life Research. He has participated as an invited expert speaker on multiple FDA panels and Industry advisory boards focused on PRO/COA development.
Li Cai,
PhD
Li Cai is Chief Scientific Officer, Consulting Psychometrician, and a Managing Partner at VPG. He earned his PhD in Quantitative Psychology from the historic LL Thurstone Psychometric Laboratory at University of North Carolina – Chapel Hill.
Li Cai is Chief Scientific Officer, Consulting Psychometrician, and a Managing Partner at VPG. He earned his PhD in Quantitative Psychology from the historic LL Thurstone Psychometric Laboratory at University of North Carolina – Chapel Hill.
Broadly speaking, his research agenda involves the development, integration, and evaluation of innovative latent variable models that have wide-ranging applications in educational, psychological, and health-related domains of study. A key component on this agenda is statistical computing, particularly as related to item response theory (IRT) and multilevel modeling. Dr. Cai has developed IRT software programs for item analysis and test scoring, such as IRTPRO and flexMIRT®, as well as the scoring engine behind VPG’s Adaptest®, a web-based pull-in for the administration and scoring of IRT-based, including adaptive, tests via commercially available EDC systems.
Michael C. Edwards,
PhD
Mike Edwards is Chief Financial Officer, co-Founder, Consulting Psychometrician, and a Managing Partner at VPG. He earned his PhD in Quantitative Psychology from the historic LL Thurstone Psychometric Laboratory at University of North Carolina – Chapel Hill.
Mike Edwards is Chief Financial Officer, co-Founder, Consulting Psychometrician, and a Managing Partner at VPG. He earned his PhD in Quantitative Psychology from the historic LL Thurstone Psychometric Laboratory at University of North Carolina – Chapel Hill.
His research is generally focused on modern psychometrics with specific emphases on item response theory (IRT), factor analysis, and issues related to dimensionality. Dr. Edwards has published over 60 peer-reviewed articles, nine chapters, and given over 70 presentations. His published work appears in a range of outlets including Autism, Journal of Abnormal Psychology, Journal of Clinical Epidemiology, Psychological Assessment, Psychological Methods, Psychometrika, and Quality of Life Research. He is currently serving as an Associate Editor for Psychological Methods.
In addition to his roles at VPG, Dr. Edwards has been a faculty member at Arizona State University since 2017. He is a Professor in the Quantitative Research Methods program within the Department of Psychology. Prior to that, he was an Assistant and Associate Professor in the Department of Psychology at The Ohio State University. While at OSU, he was chair of the Social and Behavioral Sciences institutional review board (IRB), which has enabled him to gain insight into important ethical considerations around data and privacy.
