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[Stable]

IncrementsRelativeParts is the class for increments control based on relative differences in intervals, with special rules for part 1 and beginning of part 2.

Usage

IncrementsRelativeParts(dlt_start, clean_start, ...)

.DefaultIncrementsRelativeParts()

Arguments

dlt_start

(count)
see slot definition.

clean_start

(count)
see slot definition.

...

Arguments passed on to IncrementsRelative

intervals

(numeric)
see slot definition.

increments

(numeric)
see slot definition.

Details

This class works only in conjunction with DataParts objects. If part 2 will just be started in the next cohort, then the next maximum dose will be either dlt_start (e.g. -1) shift of the last part 1 dose in case of a DLT in part 1, or clean_start shift (e.g. -1) in case of no DLTs in part 1, given that clean_start <= 0 (see description of clean_start slot for more details). If part 1 will still be on in the next cohort, then the next dose level will be the next higher dose level in the part1Ladder slot of the data object. If part 2 has been started before, the usual relative increment rules apply, see IncrementsRelative.

Slots

dlt_start

(integer)
a scalar, the dose level increment for starting part 2 in case of at least one DLT event in part 1.

clean_start

(integer)
a scalar, the dose level increment for starting part 2 in case of no DLTs in part 1. If clean_start <= 0, then the part 1 ladder will be used to find the maximum next dose. Otherwise, the relative increment rules will be applied to find the next maximum dose level.

Note

We require that clean_start >= dlt_start. However, this precondition is not a prerequisite for any function (except of the class' validation function) that works with objects of this class. It is rather motivated by the semantics. That is, if we observe a DLT in part 1, we cannot be more aggressive than in case of a clean part 1 without DLT.

Typically, end users will not use the .DefaultIncrementsRelativeParts() function.

Examples


my_increments <- IncrementsRelativeParts(dlt_start = 0, clean_start = 1)