Originally RxODE supported compound event IDs; RxODE still supports these parameters, but it is often more useful to use the the normal NONMEM dataset standard that is used by many modeling tools like NONMEM, Monolix and nlmixr, described in the RxODE event types article.
Classically, RxODE supported event coding in a single event id
evid described in the following table.
|100+ cmt||Infusion/Event Flag||<99 Cmt||SS flag & Turning of Compartment|
|100+ cmt||0 = bolus dose||< 99 cmt||1 = dose|
|1 = infusion (rate)||10 = Steady state 1 (equivalent to SS=1)|
|2 = infusion (dur)||20 = Steady state 2 (equivalent to SS=2)|
|6 = turn off modeled duration||30 = Turn off a compartment (equivalent to -CMT w/EVID=2)|
|7 = turn off modeled rate|
|8 = turn on modeled duration|
|9 = turn on modeled rate|
|4 = replace event|
|5 = multiply event|
The classic EVID concatenate the numbers in the above table, so an infusion would to compartment 1 would be
10101 and an infusion to compartment 199 would be
EVID = 0 (observations), EVID=2 (other type event) and EVID=3 are all supported. Internally an EVID=9 is a non-observation event and makes sure the system is initialized to zero; EVID=9 should not be manually set. EVID 10-99 represents modeled time interventions, similar to NONMEM’s MTIME. This along with amount (amt) and time columns specify the events in the ODE system.
For infusions specified with EVIDs > 100 the amt column represents the rate value.
For Infusion flags 1 and 2
+amt turn on the infusion to a specific compartment
-amt turn off the infusion to a specific compartment. To specify a dose/duration you place the dosing records at the time the duration starts or stops.
For modeled rate/duration infusion flags the on infusion flag must be followed by an off infusion record.
These number are concatenated together to form a full RxODE event ID, as shown in the following examples:
A 100 bolus dose to compartment #1 at time 0
A 100 bolus dose to compartment #99 at time 0
A 100 bolus dose to compartment #199 at time 0
Bolus infusion with rate 50 to compartment 1 for 1.5 hr, (modeled bioavailability changes duration of infusion)
Bolus infusion with rate 50 to compartment 1 for 1.5 hr (modeled bioavailability changes rate of infusion)
Modeled rate with amount of 50
Modeled duration with amount of 50
Steady state dose to cmt 1
Steady State with super-positioning principle for am 50 and pm 100 dose
Turn off the first compartment at time 12
Event coding in RxODE is encoded in a single event number
evid. For compartments under 100, this is coded as:
0for observation events.
amtwith the same
evidat the stop of the infusion.
For compartments greater or equal to 100, the 100s place and above digits are transferred to the 100,000th place digit. For doses to the 99th compartment the
evid for a bolus dose would be
9901 and the
evid for an infusion would be
19901. For a bolus dose to the
199th compartment the
evid for the bolus dose would be
109901. An infusion dosing record for the
199th compartment would be