Visualising emergency department capacity in an 'Emergency Department Capacity Clock': A novel tool to assess and communicate overcrowding and access block.

Hospital-wide engagement is required to alleviate the problem of ED crowding and its associated adverse effects. To this end, the article describes a novel visualisation termed 'the ED Capacity Clock', which can be formatted using business intelligence software. This radial diagram represents ED capacity and its consumption in a format that can be understood intuitively and at a glance. The ED Capacity Clock is designed to promote common understanding and discussion between relevant hospital services and also acts as an auditing tool to monitor processes implemented to alleviate ED crowding.