Pharmacists in the PC group were provided with: recent patient-specific data [e.g., peak expiratory flow rates (PEFR), acute exacerbations resulting in hospitalization or emergency department visit] displayed on a computer in their stores; materials to facilitate implementation of PC; and training on the PC program. Customers of these stores were eligible if they: filled a prescription for a breathing medication during the past 3 months; reported having asthma or COPD; were 18 years or older; filled !70% of their prescriptions in a single study store; were able to be interviewed; and resided in the community. Primary outcomes (PEFR, health-related quality of life, acute exacerbations) were assessed at 6 and 12 months. We present 6-month interim data; differences at the p < 0.05 level are considered significant. RESULTS: Asthma subjects (N=660) had a mean age of 45 years, 80% were Caucasian, and 82% female. COPD subjects (N=453) had a mean age of 62 years, 86% were Caucasian, and 66% female. At the 6-month interim analysis, the PC group did not have significantly better health-related quality of life or PEFR than either control group. The proportion of patients in the PC group with an acute exacerbation (11.4%) was not significantly different from either control group (9.4%, 9.1%). Neither was their a difference in months until the first acute exacerbation between the PC group (2.91.8) and either control group (3.11.6 and 2.31.7). CONCLUSION: Our interim (6-month) analyses found that an intensive PC program in community drug stores had no significant effect on our primary outcomes. We are currently examining long-term (12-month) outcomes, secondary outcomes (e.g., patient satisfaction), and dose-response effects. Recent studies report inconsistent findings on the changes in the incidence of hospitalizations for ischemic heart disease. These reports have relied primarily on hospital discharge data. Preliminary data suggest that a significant percentage of patients suffering acute myocardial infarction in rural communities are transferred to urban centers for care. Patients transferred to a second hospital may be counted twice for one episode of ischemic heart disease. The purpose of this study is to describe the impact of double counting and transfer bias on the estimation of incidence rates and outcomes of ischemic heart disease, specifically acute myocardial infarction, in the U.S. METHODS: Methods: Analysis of state hospital discharge data from Kansas, Colorado, Nebraska, Arizona, New Jersey, Michigan, Pennsylvania, and Illinois for the years 1995 ± 1997 for patients reported to have suffered ischemic heart disease (ICD9 codes 410 ± 414, 786.5). We developed a matching algorithm for hospital discharges to determine patients counted twice for one episode of ischemic heart disease. We validate the matching algorithm with a sensitivity analysis and chart audit. RESULTS: We found that double count rates range from 10 ± 15% for all states and have increased over the past 3 years. Moderate sized rural counties had the highest estimated double count rates at 15 ± 20% with a few counties having estimated double count rates a high as 35 ± 50%. Older patients and females were less likely to be double counted (p < .05). CONCLUSION: Conclusions: Double counting patients has resulted in a significant overestimation in the incidence rate for hospitalization for acute myocardial infarction. Correcting for this double counting reveals a significantly lower incidence rate and a higher inhospital mortality rate for acute myocardial infarction. Transferred patients differ significantly from non-transferred patients, introducing significant bias into myocardial infarction outcome studies. Double counting and transfer bias should be considered when conducting and interpreting research on ischemic heart disease, particularly in rural regions. Jan 1, 1991 and June 30, 1996 for either PE or DVT were analyzed. For each record, the first hospitalization with a principal diagnosis of DVT (N= 51,233) or PE (N = 20,017) was considered the index hospitalization. Demographic and clinical characteristics (ICD-9 codes) were compared, as were the 6-month incidences of re-hospitalization for recurrent PE or DVT, bleeding and death. Surgery defined as operation within 61 days. RESULTS: