Table 1.
Arguments for the rpsftm() function
| rpsftm() arguments | |
|---|---|
| formula | a formula with a minimal structure of Surv(time,status) ~rand(arm,rx) where
|
| Further terms can be added to the right hand side to adjust for covariates. | |
| data | an optional data frame containing the variables |
| censor_time | variable or constant giving the time at which censoring would, or has occurred. This should be provided for all observations unlike standard Kaplan-Meier or Cox regression where it is only given for censored observations. If no value is given then re-censoring is not applied. |
| subset | an expression indicating which subset of the rows of data should be used in the fit. This can be a logical vector, a numeric vector indicating which observation numbers are to be included, or a character vector of row names to be included. All observations are included by default. |
| na.action | a missing-data filter function. This is applied to the model.frame after any subset argument has been used. Default is options()$na.action. |
| test | one of survdiff, coxph or survreg. Describes the test to be used in the estimating equation. Default is survdiff. |
| low_psi | the lower limit of the range to search for the causal parameter. Default is −1. |
| hi_psi | the upper limit of the range to search for the causal parameter. Default is 1. |
| alpha | the significance level used to calculate the confidence intervals. Default is 0.05. |
| treat_modifier | an optional variable that ψ is multiplied by on an participant observation level to give differing impact to treatment. Default is 1. |
| autoswitch | a logical to autodetect cases of no switching. Default is TRUE. If all observations in an arm have perfect compliance then re-censoring is not applied in that arm. If FALSE then re-censoring is applied regardless of perfect compliance. |
| n_eval_z | The number of points between hi_psi and low_psi at which to evaluate the Z-statistics in the estimating equation. Default is 100. |