The influence of ambulance offload time on 30‐day risks of death and re‐presentation for patients with chest pain

In reply: We thank Mallows and colleagues1 for their interest in our study.2 We agree that assessing the interaction between access block, emergency department (ED) overcrowding, and ambulance offload times would have contributed to improved interpretation of the data. Unfortunately, measures of ED overcrowding are not available in the Victorian Emergency Minimum Dataset. It is important to note that the studies referenced by Mallows and colleagues have similar limitations in either assessing a combined hospital overcrowding measure, or ED overcrowding and access block without adjustment for hospital overcrowding.3,4 Ambulance offload delays, ED overcrowding and access block could all be considered a symptom for hospital overcrowding, with the latter driving poor outcomes. This uncertainty is clearly presented in our manuscript in Box 1.2