h_adlb_abnormal_by_worst_grade {tern}

Helper function to prepare ADLB for count_abnormal_by_worst_grade()

Description

Helper function to prepare an ADLB data frame to be used as input in count_abnormal_by_worst_grade(). The following pre-processing steps are applied:

1. adlb is filtered on variable avisit to only include post-baseline visits.

2. adlb is filtered on variables worst_flag_low and worst_flag_high so that only worst grades (in either direction) are included.

3. From the standard lab grade variable atoxgr, the following two variables are derived and added to adlb:

• A grade direction variable (e.g. GRADE_DIR). The variable takes value "HIGH" when atoxgr > 0, "LOW" when atoxgr < 0, and "ZERO" otherwise.

• A toxicity grade variable (e.g. GRADE_ANL) where all negative values from atoxgr are replaced by their absolute values.

1. Unused factor levels are dropped from adlb via droplevels().

Usage

h_adlb_abnormal_by_worst_grade(
  adlb,
  atoxgr = "ATOXGR",
  avisit = "AVISIT",
  worst_flag_low = "WGRLOFL",
  worst_flag_high = "WGRHIFL"
)

Arguments

adlb

(data.frame)
ADLB data frame.

atoxgr

(string)
name of the analysis toxicity grade variable. This must be a factor variable.

avisit

(string)
name of the analysis visit variable.

worst_flag_low

(string)
name of the worst low lab grade flag variable. This variable is set to "Y" when indicating records of worst low lab grades.

worst_flag_high

(string)
name of the worst high lab grade flag variable. This variable is set to "Y" when indicating records of worst high lab grades.

Value

h_adlb_abnormal_by_worst_grade() returns the adlb data frame with two new variables: GRADE_DIR and GRADE_ANL.

See Also

abnormal_by_worst_grade

Examples

h_adlb_abnormal_by_worst_grade(tern_ex_adlb) %>%
  dplyr::select(ATOXGR, GRADE_DIR, GRADE_ANL) %>%
  head(10)