library(haven)
library(magrittr)
library(Tplyr)

adae <- read_xpt("adae.xpt")


t <- tplyr_table(adae, TRTA) %>%
  add_layer(
    group_count(RACE) %>%
      set_distinct_by(USUBJID) %>%
      add_risk_diff(
        c("Xanomeline High Dose", "Placebo"),
        c("Xanomeline Low Dose", "Placebo")
      )
  )

build(t)