psychometrics, patient-reported outcomes, item response theory, linking

I am a research psychologist with expertise in measurement science, psychometrics, and self-reported physical and mental health. My primary scientific mission is to advance reliable and valid assessment of health-related quality of life. I believe that improvements in health services and outcomes research depend in large part upon patient-centered assessments, which can evaluate the quality and effectiveness of interventions. This requires the standardization of common patient-reported outcomes (PROs), such as pain, fatigue, depression, anxiety, cognitive function, physical function, but also process domains, such as patient self-efficacy and engagement.

Most of my work has concentrated on the psychometric procedures used to develop and implement instruments of the patient-reported outcome and information system (PROMIS), such as item response theory (IRT) and computer adaptive testing (CAT). In recent years I have focused specifically on one of the many challenges to advancing outcomes research: to effectively and accurately combine data on similar psychological and health constructs. An impediment to such harmonization is the proliferation of patient-centered assessments, of varying quality and properties, purporting to measure similar constructs. A methodology called linking, as applied in our PROsetta Stone project at Northwestern University, represents an important way to address this problem, and has been a major focus of my research.