: Guidelines for providing quality care to patients with acute myocardial infarction (AMI) based on randomized controlled trial (RCT) evidence may not be appropriate in higher risk groups because of limited external validity imposed by stringent RCT exclusion criteria. Like the Agency for Healthcare Research and Quality (AHRQ) priority populations, RCT ineligible populations are often characterized by risk factors that typically indicate the need for additional or specialized care. Chronic conditions and comorbidities, disability, special health care needs and advanced age are all considered priority populations by AHRQ and are standard exclusion criteria for RCTs. The VA patient population shares a number of these risk factors, i.e. increased comorbidites and disability, in addition to high proportions of low income and rural patients also considered priority populations by AHRQ. This dilemma of less quality evidence for those in more need of care is amplified by the methodological challenges and ethical constraints of randomization in high risk groups. The overall objective of this project will use veterans as an example of a population typically excluded from RCTs to examine how they differ from the general population and to specifically examine outcomes for this population and as they relate to characteristics that make veterans ineligible for most RCTs. This objective is divided into three specific aims: 1) To describe the population of VA patients admitted with AMI and compare it to those patients represented in community based AMI registries using standard descriptive statistics; 2) to compare outcomes for VA patients with an ECG diagnosed ST-elevated myocardial infarction (STEMI) receiving reperfusion within guideline recommended time to those receiving later reperfusion using multivariable regression; 3) to describe the population of VA patients based on time from symptom onset to hospital arrival and evaluate outcomes for those presenting more than 12 hours from symptom onset using instrumental variable analysis. Because veterans often have one or more characteristics typically making them ineligible for RCTs, guidelines for treatment based on this evidence may not represent the best quality care for them. Prior to investing additional resources implementing quality improvement interventions to meet guideline recommendations, an indepth examination of characteristics and outcomes specific to the veteran population with AMI is important to better inform resource allocation and provide optimal individualized care. ? ? ?
