Almost every domain of quality is reduced in crowded emergency departments (ED), with significant challenges around the definition, measurement and interventions for ED crowding. The most widely known tool to measure crowding is NEDOCS; this is a validated score. In Saint John, there is a local tool based on NEDOCS, known locally as the ED Saturation Calculator. We wished to determine if a combination of 3 easily measurable variables could perform as well as these standard tools (NEDOCS score and a NEDOCS-derived LOCAL tool) in predicting ED crowding in the Saint John Regional Hospital, a tertiary hospital with 57,000 visits per year.