Fig. 2

Equations for model predicting frequent emergency department (ED) use as defined as 8 or more visits (a) and model predicting frequent ED use as defined as 16 or more visits in the subsequent two years (b). Distance (<=5): the straight-line distances between geographic points from patients’ home to hospital less than 5 miles; Distance (>20): the straight-line distances between geographic points from patients’ home to hospital greater than 20 miles; CC: chief complaints; GI: gastrointestinal; RESP: respiratory; NEURO: neurological; UDI: undifferentiated infection; ILI: influenza-like illness and MUSC: musculoskeletal