Rajesh Balkrishnan, PhD, Professor of Public Health Sciences, Director of the Cancer Control Core, and UVA Cancer Center Co-Director, Population Health and Prevention Research recently led a workshop at the annual meeting of the International Society of Pharmacoeconomics and Outcomes Research (ISPOR).
ABSTRACT: In this workshop, we will discuss our experience from evaluation of newer measures and techniques like the Two-step Floating Catchment Area (2SFCA), geographic hot spot analyses, and geographic weighted regression in evaluating the access and utilization of adjuvant endocrine therapy in breast cancer survivors residing in Appalachia, an underserved region in the United States with significant geospatial access issues. The 2SFCA approach first identifies a prescriber catchment area in the first step and then computes a prescriber to population ratio for each physician’s catchment in the second step. The step one ratios within a population’s catchment are then summed, resulting in an access score for each population location. Geographical hot spot analyses can help identify geographic clustering patterns of medication use behaviors. Geographic weighted regression in which regression weights can vary as a function of geographical location can be used to examine spatial non-stationarity of the relationships between predicators and medication use outcomes. We will present results of comparative analyses which demonstrate the superior efficiency of estimates obtained from these analyses as well as discuss practical approaches to implementing and using these methodologies in medication use studies using large databases.