When QueueMetrics run an activity report, its basic "unit of measurement" is the queue; that is the activity that your call made on a specific queue. This may lead to a situation that is harder to understand if you have spill-over queues in place, that is, if a call is not handled in one queue it is moved to a different one.

In order to address this problem, queueMetrics implements a multi-stint analysis mode, where mutiple passages on different queues are "joined together", like in the following example. Imagine this call:
h 10.00.00 enters queue 1
h 10.00.59 exits queue 1
h 10.01.00 enters queue 2
h 10.01.59 exits queue 2
h 10.02.00 enters queue 3
h 10.02.30 answered on queue 3
h 10.03.00 caller hangs up
With single stint mode you would see:
h 10.00.00 lost call on "queue 1", waited for 59 seconds
h 10.01.00 lost call on "queue 2", waited for 59 seconds
h 10.02.00 answered call on "queue 3", waited for 30 seconds, duration 30 seconds
With multi-stint mode you would see:
h 10.00.00 call enters on queue 3, waits for 2:30, duration 30 seconds
and by clicking on the call detail, you get the whole history.

In order to have multi-stint work correctly, you should include ALL the queues that the call was handled upon in the same report - otherwise it will not find out where the call passed.

Of course, in real-life you can run both multi-stint and single-stint analyses when querying the performance of your call-center; you use multi-stint to see the performance from the point of view of the caller, and single-stint to see what happended from the point of view of the providers, e.g. service groups.