Helper Function to Prepare ADLB with Worst Labs

Helper function to prepare a df for generate the patient count shift table

Usage

h_adlb_worsen(
  adlb,
  worst_flag_low = NULL,
  worst_flag_high = NULL,
  direction_var
)

Arguments

adlb

(data.frame)
ADLB dataframe

worst_flag_low

(named vector)
Worst low post-baseline lab grade flag variable

worst_flag_high

(named vector)
Worst high post-baseline lab grade flag variable

direction_var

(string)
Direction variable specifying the direction of the shift table of interest. Only lab records flagged by L, H or B are included in the shift table.

• L: low direction only

• H: high direction only

• B: both low and high directions

Value

h_adlb_worsen() returns the adlb

data.frame containing only the worst labs specified according to worst_flag_low or worst_flag_high for the direction specified according to direction_var. For instance, for a lab that is needed for the low direction only, only records flagged by worst_flag_low are selected. For a lab that is needed for both low and high directions, the worst low records are selected for the low direction, and the worst high record are selected for the high direction.

See also

abnormal_by_worst_grade_worsen

Examples

library(dplyr)

# The direction variable, GRADDR, is based on metadata
adlb <- tern_ex_adlb %>%
  mutate(
    GRADDR = case_when(
      PARAMCD == "ALT" ~ "B",
      PARAMCD == "CRP" ~ "L",
      PARAMCD == "IGA" ~ "H"
    )
  ) %>%
  filter(SAFFL == "Y" & ONTRTFL == "Y" & GRADDR != "")

df <- h_adlb_worsen(
  adlb,
  worst_flag_low = c("WGRLOFL" = "Y"),
  worst_flag_high = c("WGRHIFL" = "Y"),
  direction_var = "GRADDR"
)