Defining successful program configurations in VA home-based primary care: a study protocol to identify key difference-makers through investigating cross-case heterogeneity in program implementation.

backgroundThe Department of Veterans Affairs (VA) is the largest integrated healthcare system in the United States and serves a rapidly aging patient population. The VA's Home-Based Primary Care (HBPC) program is a home care model for older, complex, high-risk Veterans that provides comprehensive, longitudinal primary care delivered by an interdisciplinary team of VA staff, with plans for expansion by 2027. HBPC program implementation varies considerably across local sites and contexts. Accordingly, these characteristics offer a unique opportunity to investigate real-world, cross-case heterogeneity and identify crucial factors that may lead to improved patient outcomes.

methodsPatient home time in the last 180 days of life will serve as the primary outcome measure, calculated at the patient-level as the total days not in an acute care (e.g., emergency department [ED], hospital), post-acute care (e.g., skilled nursing facility), or institutional long-term care setting (e.g., nursing home) in the 180 days prior to death. Secondary outcomes include patient satisfaction and other utilization outcomes: ED visits, hospitalizations, days in long term care, care transitions, hospice use prior to death, and site of death. Multiple datasets will be combined to obtain a comprehensive view of HBPC site characteristics. This study will use an exploratory sequential mixed methods design to describe the heterogeneity in HBPC program implementation and evaluate how contextual factors and program delivery patterns influence home time and other patient outcomes. Analyses will identify difference-making configurations of contextual, operational, cultural, and care delivery factors that distinguish high- versus low-home time sites. Analytic methods include quantitative descriptive analyses, regression analyses, in-depth qualitative case studies at 10 high and 10 low home time sites, qualitative cross-case analysis, and the application of Coincidence Analysis to identify successful HBPC program configurations. DISCUSSION: Health care systems can take advantage of real-world heterogeneity in program implementation across sites that vary in context and setting to identify the key difference-makers and use these findings to inform future program expansion. By understanding which HBPC program features lead to improved outcomes for older adults in specific contexts, the VA can learn where site variation is a positive sign of adaptation versus a sign of inefficiency and an opportunity for improvement. CLINICAL TRIAL NUMBER: Not applicable.