plot_-forest命令给出了以下错误：用于定义子组的变量不是分类的

我试图为不同的子组（变量）按女性变量分层的Cox回归做森林图。 我使用了以下代码

library(SubgrPlots)
dat<-subset(data, select=c( "comp2_years","comp2", "FEMALE", "Age75yoryears","Diabetes","MI", "LVEF_pre","offpump",
                            "MAG"))
dat$comp2<-as.numeric(dat$comp2)
#dat$comp2 = as.factor(dat$comp2)
dat$FEMALE = as.factor(dat$FEMALE)

str(dat)
dat = dat %>%
  mutate(Age75yoryears = factor(ifelse(Age75yoryears == 0 , "No", "Yes")),
         Diabetes = factor(ifelse(Diabetes == 0 , "No", "Yes")),
         MI = factor(ifelse(MI == 0 , "No", "Yes")),
         LVEF_pre = factor(ifelse(LVEF_pre == 0 , "No", "Yes")),
         offpump = factor(ifelse(offpump == 0 , "No", "Yes")),
         MAG = factor(ifelse(MAG == 0 , "No", "Yes")) )

## Figure 1: Forest Plot ------------------------------------------------------
main.title = list("", "Forest plot of subgroups",
                  "Kaplan-Meier curves\n by treatment group")
label.x = list("", "hazard ratio",   "Time (days)")

plot_forest(dat,
            covari.sel = c(4, 5, 6, 7,8,9),
            trt.sel = 3, # treatment code
            resp.sel = c(1, 2), # response variable
            outcome.type = "survival", 
            size.shape = c(0.3, 6.5 / 4),
            font.size = c(1, 1, 1, .8),
            title = main.title,
            lab.x = label.x, time = 50,
            KM = T,
            show.km.axis =T,
            n.brk = 6, max.time = 70,
            widths = c(2, 1.5, 1),
            eff.scale = c("HR"))

如有任何建议，将不胜感激

> str(dat)
tibble[,9] [13,803 x 9] (S3: tbl_df/tbl/data.frame)
 $ comp2_years  : num [1:13803] 10 10 10 10 9.77 ...
 $ comp2        : Factor w/ 2 levels "0","1": 1 1 1 1 2 1 1 1 1 1 ...
 $ FEMALE       : Factor w/ 2 levels "0","1": 1 2 1 1 1 1 2 1 1 1 ...
 $ Age75yoryears: Factor w/ 2 levels "No","Yes": 1 1 1 1 1 1 1 1 1 1 ...
 $ Diabetes     : Factor w/ 2 levels "No","Yes": 1 1 2 2 1 1 2 1 1 1 ...
 $ MI           : Factor w/ 2 levels "No","Yes": 1 1 1 1 2 1 1 1 1 1 ...
 $ LVEF_pre     : Factor w/ 2 levels "No","Yes": 1 1 1 1 1 1 1 1 1 1 ...
 $ offpump      : Factor w/ 2 levels "No","Yes": 2 2 2 2 2 2 2 2 2 2 ...
 $ MAG          : Factor w/ 2 levels "No","Yes": 1 2 2 1 2 2 2 1 2 1 ... ```