NextBestEWOC-class: 'NextBestEWOC'

In crmPack: Object-Oriented Implementation of Dose Escalation Designs

NextBestEWOC

Description

NextBestEWOC is the class implementing Escalation With Overdose Control (EWOC). It recommends the highest possible dose subject to a probabilistic constraint that the posterior probability of overdosing does not exceed max_overdose_prob. Overdosing is defined as the model-based toxicity probability lying inside the interval given by overdose.

Usage

NextBestEWOC(target, overdose, max_overdose_prob)

.DefaultNextBestEWOC()

Arguments

target	(proportion) see slot definition.
overdose	(numeric) see slot definition.
max_overdose_prob	(proportion) see slot definition.

Slots

target

(proportion)
target toxicity probability to be achieved, below overdose[1]; only used for simulation reporting purposes.

overdose

(numeric)
the (exclusive) lower and (inclusive) upper boundaries of the toxicity probability interval considered an overdose region. The prototype uses c(0.35, 1) meaning probabilities > 0.35 are treated as overly toxic.

max_overdose_prob

(proportion)
maximum acceptable posterior probability that the next recommended dose is in the overdose interval.

Note

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

See Also

NextBest, other next-best classes listed in its documentation.

Examples

# Example: Define EWOC next best dose rule.
# Target toxicity probability is 0.30. Overdose region is any probability > 0.35.
# We restrict posterior probability of recommending an overdosing dose to <= 0.25.
next_best_ewoc <- NextBestEWOC(
  target = 0.30,
  overdose = c(0.35, 1),
  max_overdose_prob = 0.25
)

crmPack documentation built on Nov. 29, 2025, 5:07 p.m.