Parse a string of phase I/II dose-finding trial outcomes. — parse_eff_tox_dose_finding

Parse a string of phase I/II dose-finding trial outcomes. Phase I/II trials conduct dose-finding by efficacy and toxicity outcomes.

Parse a string of phase I/II dose-finding outcomes to a list. The outcome string describes the doses given, efficacy and toxicity outcomes observed and the timing of analyses that recommend a dose. The format of the string is described in Brock _et al_. (2017). The letters E, T, N & B are used to represents patients that experienced (E)fficacy, (T)oxicity, (N)either and (B)oth. These letters are concatenated after numerical dose-levels to convey the outcomes of cohorts of patients. For instance, 2NET represents a cohort of three patients that were treated at dose-level 2, one of whom experienced toxicity only, one that experienced efficacy only, and one that had neither. The results of cohorts are separated by spaces and it is assumed that a dose-finding decision takes place at the end of a cohort. Thus, 2NET 1NN builds on our previous example, where the next cohort of two were treated at dose-level 1 and neither of these patients experienced either event. See examples.

parse_eff_tox_dose_finding_outcomes(outcome_string)

Arguments

outcome_string	character representing doses given, outcomes observed, and timing of analyses. See Description.

Value

a list with a slot for each cohort. Each cohort slot is itself a list, containing elements: * dose, the integer dose delivered to the cohort; * outcomes, a character string representing the E, T N or B outcomes for the patients in this cohort.

References

Brock, K., Billingham, L., Copland, M., Siddique, S., Sirovica, M., & Yap, C. (2017). Implementing the EffTox dose-finding design in the Matchpoint trial. BMC Medical Research Methodology, 17(1), 112. https://doi.org/10.1186/s12874-017-0381-x

Examples

x = parse_eff_tox_dose_finding_outcomes('1NEN 2ENT 3TB')
length(x)
#> [1] 3
x[[1]]$dose
#> [1] 1
x[[1]]$outcomes
#> [1] "NEN"
x[[2]]$dose
#> [1] 2
x[[2]]$outcomes
#> [1] "ENT"
x[[3]]$dose
#> [1] 3
x[[3]]$outcomes
#> [1] "TB"