This method stops a dose-finding trial when there are n patients at a dose. It can stop when the rule is triggered at the recommended dose, at a particular dose, or at any dose.

stop_when_n_at_dose(parent_selector_factory, n, dose)

Arguments

parent_selector_factory

Object of type selector_factory.

n

Stop when there are n at a dose.

dose

'any' to stop when there are n at any dose; 'recommended' to stop when there are n at the recommended dose; or an integer to stop when there are n at a particular dose-level.

Value

an object of type selector_factory that can fit a dose-finding model to outcomes.

Examples

skeleton <- c(0.05, 0.1, 0.25, 0.4, 0.6)
target <- 0.25

# This model will stop when 12 are seen at any dose:
model1 <- get_dfcrm(skeleton = skeleton, target = target) %>%
  stop_when_n_at_dose(n = 12, dose = 'any')

# This model fit will not stop:
model1 %>% fit('1NNN 2NTN 2TNN 2NNN') %>% continue()
#> [1] TRUE
# But this model fit will stop:
model1 %>% fit('1NNN 2NTN 2TNN 2NNN 2NTT') %>% continue()
#> [1] FALSE

# This model will stop when 12 are seen at the recommended dose:
model2 <- get_dfcrm(skeleton = skeleton, target = target) %>%
  stop_when_n_at_dose(n = 12, dose = 'recommended')

# This model fit will not stop:
fit2 <- model2 %>% fit('1NNN 2NTN 2TNN 2NNN')
fit2 %>% recommended_dose()
#> [1] 2
fit2 %>% continue()
#> [1] TRUE
# But this model fit will stop:
fit3 <- model2 %>% fit('1NNN 2NTN 2TNN 2NNN 2NNT')
fit3 %>% recommended_dose()
#> [1] 2
fit3 %>% continue()
#> [1] FALSE