PROJECT SUMMARY One in five individuals, or 53 million people, are currently acting as unpaid caregivers in the United States. Caregivers directly contribute to patient safety and health outcomes by navigating health care systems, managing complex care, and advocating for the needs of patients. During the high-risk process of hospital discharge, caregiver involvement supports preparedness and continuity of care; decreased preparedness of caregivers for discharge results in an increased risk for readmission to the hospital. CMS requires education of patients, family, guardians, and/or caregivers about self-management, independent living, and activities of daily living in order to be reimbursed for “care management” services, and more than 30 states have adopted the Caregiver Advise Record Enable (CARE) Act requiring active engagement of caregivers in discharge planning and education. However, there is no unique outcome measure available to assess how well-prepared caregivers are to engage in caregiving activities after care recipients’ hospital discharge. Current measures of caregivers 1) focus exclusively on general caregiver outcomes such as physical and mental wellbeing, 2) were developed for retrospective reporting of transitional care quality vs timely application in real world clinical settings, or 3) lack rigorous reporting of psychometric testing. Simply put, current measures don’t capture caregivers’ specific perceptions about their own level of preparedness during the high-risk event of hospital discharge. As a result, health systems lack a practical measure for assessing the effectiveness of discharge preparation of caregivers, and we are left without a firm understanding of how caregiver readiness may contribute to patients’ safe transitions home. The goal of this study is to develop and test a measure that captures the unique factors important to caregivers’ feelings of readiness to engage in caregiving. Using a mixed-methods approach, the specific aims of this study are to 1) develop a theoretically grounded and psychometrically sound caregiver hospital discharge readiness scale (FamRHDS-R); 2) establish the psychometric properties and measurement invariance of the new FamRHDS-R; and 3) establish whether and how the new FamRHDS-R is associated with a range of caregiver and patient outcomes. The overall hypothesis is that the new FamRHDS-R measure assessing caregiver readiness to engage in caregiving will capture and explain variability in post-discharge patient and caregiver outcomes. Because this study is responsive to the needs of both health systems and caregivers, and seeks to refine and test a tool based on measures already implemented in over 35 health systems nationwide, this highly significant study is well positioned to substantially impact hospital discharge quality and health outcomes including reduced readmissions and overall costs of care.