PROJECT SUMMARY/ ABSTRACT Chronic Obstructive Pulmonary Disease (COPD) is an increasingly prevalent and costly chronic health condition, and is the third major cause of morbidity and mortality in the United States. Self-management treatment programs for COPD are shown to improve health-related quality of life and prevent COPD-related hospitalizations. Despite their clinical benefits, these programs are typically multi-component and time- and resource-intensive. To date, no study has been conducted to isolate the role of individual self-management treatment components in contributing to improved COPD outcomes. The current application proposes to establish the feasibility of using the Multiphase Optimization Strategy (MOST) framework to optimize COPD self-management treatment delivered by the American Lung Association (ALA) Helpline. Treatment components to be evaluated include duration of self-management education, ground-based walking training, peer support, and caregiver support. The primary outcome is health-related quality of life, with secondary outcomes of COPD symptom burden, self-management behaviors, and hospitalization. Specific aims are: Aim 1. Design a factorial experiment and develop operational procedures (i.e., screening/ recruitment, randomization, and database management) for successful implementation. Aim 2. Establish feasibility and acceptability by pilot testing the study design with an initial sample of 48 individuals with COPD. Resulting values will provide estimates of recruitment and retention rates, outcome measure variability, treatment fidelity, and acceptability of treatment components to inform a subsequent fully-powered optimization trial. The proposed project will also establish the PI as one of the few researchers employing optimization methods within the field of COPD self-management. Dr. Mathew is currently completing an NHLBI K23 award (K23 HL138165) to develop and test a tailored smoking cessation intervention for individuals with COPD. The proposed R03 will extend her treatment development work to additional behavioral health targets addressed by COPD self-management treatment, such as dyspnea management, medication adherence, physical activity, and diet. Public Health Impact: The proposed study is an initial step to address a critical research gap regarding identifying effective elements of COPD self-management treatment. The long-term goal of this line of research is to optimize the effectiveness of multi-component COPD self-management interventions, and reduce COPD-related disease burden.