get_r2_flex {OneArmPhaseTwoStudy} | R Documentation |
Calculates the number of responses needed for the second stage of a Simon's two-stage design if the flexible extension is chosen in the planning phase.
get_r2_flex(ce, p0, n2)
ce |
conditional error for the second stage. |
p0 |
probability for a response under the null hypothesis. |
n2 |
sample size for the second stage. |
getD_proportionally
, getD_equally
, getD_distributeToOne
, getD_none
#Calculate a Simon's two-stage design design <- getSolutions()$Solutions[3,] #minimax-design for the default values. #Get the conditional error values using proportionally "rest"-alpha spending. ce_df <- getD_proportionally(design, 0.05) #Assume 5 responses were observed in the interim analysis. ce <- ce_df[5+1,]$ce # conditional error for 5 responses is listed in the 6th row of "ce_df" #Calculate the number of patients needed in the second stage. n2 <- design$n - design$n1 r2 <- get_r2_flex(ce, design$p0, n2) r2 #Assume 10 patients more should be recruited in the second stage. #(This changes the number of needed responses.) n2 <- n2 + 10 r2 <- get_r2_flex(ce, design$p0, n2) r2