The economic impact of DUR interventions on the pharmacological management of asthma in children

Abstract

The purpose of the dissertation was to assess the economic impact of a DUR intervention among children enrolled in the Pennsylvania Medicaid program who had overused SA beta2-agonist inhalation drugs. This research expanded on previous work, the base study, titled 'Pennsylvania Medicaid Retrospective Drug Utilization Review Program Improvement of the Pharmacological Management of Asthma in Children Enrolled in the Pennsylvania Medicaid Fee-for-Service Program' conducted by the Center on Drugs and Public Policy, University of Maryland and Pennsylvania Medical Society for the Commonwealth of Pennsylvania, Department of Public Welfare. This base study was descriptive in design and did not include a control group. The dissertation used scientifically controlled research methodologies to assess the base study results and evaluate whether a true DUR intervention effect existed. It used various multivariate techniques designed to control for non-intervention related influences. Four pre/post comparison series designs to address uncontrolled confounders such as regression to the mean, history, and maturation were used. These included (a) a self-controlled historical comparison group design, (b) a historical equivalent comparison group design, (c) a concurrent non-equivalent comparison group design, and (d) a regression discontinuity design. The self-controlled historical comparison group design was a single-group pre/post design that monitored trends in resource utilization among the intervention group in a year previous to the DUR claims review period. The historical equivalent comparison group design was a two-group design that compared the DUR intervention group to a comparison group identified by the same criteria as the intervention group in a year previous to the DUR claims review period. The concurrent non-equivalent comparison group design and the regression discontinuity design were two-group designs that utilized two different methods of analyses to compare the intervention group to a control group in the concurrent period. The end-points of interest were cost of asthma medications, asthma-related hospitalizations, and asthma-related emergency department visits. The study used Pennsylvania Medicaid administrative and prescription claims data for the period July 1997 to March 2000 residing at the CDPP. The robustness of each study design's findings to the base study results was analytically assessed. None of the four scientifically controlled study designs showed a significant positive DUR effect. The base study results were confounded by regression to the mean, history, and/or maturation.