Residual trend is the difference between total trend and the portion of the total trend caused by changes in provider reimbursement levels.
Consider the following events that could affect an health plan’s provider reimbursement levels:
Event 1 — The disenrollment of a large group with unusually high utilization rates
Event 2 — The introduction of a new treatment for infertility
Event 3 — A serious flu epidemic
Event 4 — A shift in inpatient medical services from obstetrical care to neonatal intensive care
One cause of residual trend is change in intensity, which would be represented by: