QDM 4.0 defines the "starts during" operator as asserting "that the start date/time of an event on the left-hand side is both 1) temporally after or equal to the start date/time of an event on the right-hand side; and 2) temporally before or equal to the end date/time of the same right-hand side event.

During the QDM 4.1 training call, the QDM team mentioned that in fact, the operator does not include the end date/time of the right-hand side event. It was our understanding that this operator matched the QDM 4.0 definition, so we are unsure of the impact of this QDM definition change on measures that already use the "starts during" operator; i.e. have any measure engines implemented the QDM 4.1 definition of this operator (e.g. Cypress/Bonnie)? Should this change in the definition be applied retroactively?