Includes bibliographical references. ; Summer ; High Short-Acting β−Agonists (SABA) use is an important indicator of poor asthma control and has been utilized in various studies as a proxy measure of asthma control for various purposes (e.g. predictive marker for future exacerbation events). However, little evidence exists with regard to the optimal measurement of high SABA use for predicting future exacerbation events as well as the impact of asthma control, as measured by high SABA use and other characteristics, on Health Related Quality of Life (HRQoL) and Health Resource Utilization (HRU). The objective of this research was to determine the measure of high SABA use that is most predictive of future exacerbation events and to assess the impact of asthma control, as measured by high SABA use and other claims-derived characteristics, on HRQoL and HRU. We used a retrospective cohort of persistent asthma patients from the Observational Study of Asthma Control & Outcomes (OSACO) for this dissertation. Specifically, patients included in the analytical cohort completed all 3 surveys and were continuously enrolled from April 2011 to June 2012. We compared measures of high SABA use via accuracy, discrimination, calibration, and clinical utility. The two measures of high SABA use (i.e. primary exposure measures) that were compared were Asthma Medication Ratio (AMR) and SABA canister count. Classification of asthma control status was according to a model based on high SABA use and other characteristics. The primary outcome measure for aim 1 was exacerbation events (asthma-related hospitalizations, Emergency Department (ED) visits, and outpatient visits with Oral Corticosteroid (OCS) burst); asthma-specific and generic HRQoL scores for aim 2 and; HRU for aim 3. We assessed the impact of change in asthma control status on asthma-specific and generic HRQoL using a mixed modeling approach and the impact of change in asthma control status on all-cause and asthma-specific HRU was assessed using generalized linear models. ...