High hospital volume is associated with more consistent long-term mortality rates

Long-term survival following cancer treatment is a widely accepted metric used to evaluate the quality of cancer care and varies between hospitals (1-3). Long-term survival takes years to evaluate, and these metrics reflect care quality from many years prior. Long-term survival has unknown applicability as a quality measure to evaluate current performance. It is important to determine if the structural lag in measurement limits the value of long-term survival measures meaningless as a tool for assessing current hospital performance. The study assesses the stability of hospitals’ performance over time based on its cancer patients’ fouryear survival. We hypothesized that hospitals’ four-year mortality ratio would be consistent over time, implying that patients could use such information when deciding where to get care. Additionally, since decades of research have demonstrated a relationship between higher surgical volume and better outcomes for hospitals, we set out to explore consistency by hospital volume (1,4).