Fig 4.

Projecting outpatient imaging volume from orders. The model effectively shows how many examinations should have been done considering the drop in orders. The gap between the model output and the actual examination volume accounts for the examinations added to the backlog (shown in light orange), which in our case are only the examinations that were scheduled and then cancelled, awaiting rescheduling. After the surge, model output is lower than actual examination volume; this is explained by technologists’ working through backlogged examinations. Abrupt drops in imaging volume correspond to weeks with holidays.