Background: As many as 7 out of 10 hospitalized patients experience asymptomatic blood pressure (BP) elevations while in the hospital. However, no guidelines exist to guide the management of inpatient BP elevations. And, literature suggests treating these elevations with short-acting “as needed” BP medications (PRN BP), especially if asymptomatic, may be harmful. Despite this, many providers treat asymptomatic BP elevations with PRN BP. Significance: Adverse events due to overtreatment of inpatient BP elevations may lead to poor patient outcomes and higher hospitalization costs. Veterans, by virtue of older age and high prevalence of co- morbidities, are a population at high risk for adverse effects from inpatient BP treatment. Thus, it is vital to understand the practice patterns and provider motivations for PRN BP prescribing in VA hospitals in order to design interventions to target proper PRN BP use in hospitals. Such interventions can be tested for impact on safety and cost attributable to this practice. This work addresses VHA HSR&D priorities of Quality and Safety of Health Care, Health Care Value and Health Care Informatics. Innovation and Impact: The proposed work is novel in that it leverages extensive clinical electronic health record and administrative data and marries it with granular data from provider and nursing interviews (locally at a single VA hospital) and a national survey to better understand the full arc of predictors and motivations for prescribing in a low cost, timely fashion. Ultimately, the impact of this project is that it will provide fundamental infromation that will lead to the design, development and testing of interventions aimed at optimizing provider and nursing use of PRN BP. This intervention can be tested via cluster randomized trials to optimize related safety and costs of care. Specific Aims: Aim 1. To identify the prevalence of PRN BP use, and the sociodemographic and clinical factors associated with PRN BP use among Veterans hospitalized in VA hospitals nationally from FY16- FY20. Aim 2. To understand provider, nursing and system-level factors motivating PRN blood pressure use in VA hospitals through qualitative research techniques Methods: We will use VINCI resources to create a cohort from the national VHA of all Veterans consisting of all non-intensive care unit admissions to VA hospitals in FY16-20. Using several VA data sources including the Pharmacy Benefit Management and the Corporate Data Warehouse, we will define PRN BP use during hospitalization and collect diagnosis codes and specific clinical data including BP and kidney function measures. In Aim 1, will describe the prevalence of PRN BP prescribing and factors that predict prescription of PRN BP. In Aim 2, we will complement our findings from Aim 1 through 1 on 1 interviews with providers and nurses at a single VA tertiary care hospital to explore system-level and individual-level motivating factors for PRN BP use. We will use themes that em...