Waiting times and hospitalizations for ambulatory care sensitive conditions

Long waits for health care are hypothesized to cause negative health outcomes due to delays in diagnosis and treatment. This study uses administrative data to examine the relationship between time spent waiting for outpatient care and the risk of hospitalization for an ambulatory care sensitive condition (ACSC). Data on the number of days until the next available appointment were extracted from Veterans Affairs (VA) medical centers. Two methodological issues arose. First, the simultaneous determination of individual health status and wait times due to medical triage was overcome by developing an exogenous wait time measure. Second, selection bias due to unobserved case mix differences was minimized by separating in time the sample selection period from the period when wait times and outcomes were measured. Exogenous facility-level wait time was the main variable of interest in a fixed effects stacked heteroskedastic probit regression model that predicted the probability of ACSC hospitalization in each month of a six-month period. There was a significant and positive relationship between facility-level wait times and the probability of experiencing an ACSC hospitalization, especially for facility-level wait times of 29 days or more. Further research is needed to replicate these findings in other populations and among those with different clinical histories. As well, policymakers and researchers need an improved understanding of the causes of long wait times and interventions to decrease wait times. © Springer Science+Business Media, LLC 2007.