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Create Subject-level Flag from Long Data

Source: R/subject_level_flag.R
subject_level_flag.Rd

Utility for creating subject-level flags from data frames that are more than one line per subject. For example, use this function to create a flag indicating whether a subject experienced any serious adverse events.

The function works by first creating a logical variable in data_long indicating whether the condition passed in the ... argument is met. If a subject has true on any row, then the new variable is added to data as TRUE, otherwise that subject's value is populated with a FALSE.

Usage 

subject_level_flag(data, data_long, ..., .key = "USUBJID")

Arguments

data

(data.frame)
a subject-level data frame, e.g. adsl

data_long

(data.frame)
a long data frame that is more than one line per subject, e.g. adae. The expressions passed in ... will be evaluated in this data frame.

...

(data-masking)
Name and condition pairs. The name is the name of the new subject-level flag column. The condition is an expression that results in a logical vector. These name-condition pairs are passed directly to dplyr::mutate(...).

.key

(character)
Key columns create flags within and to merge by. Default is 'USUBJID'

Value

Subject-level data frame

Examples 

adsl <- tibble::tribble(
  ~USUBJID,      ~SEX,
  "01-701-1015", "F",
  "01-701-1023", "M",
  "01-701-1028", "M"
)

adae <- tibble::tribble(
  ~USUBJID,      ~AESER, ~AEACN,
  "01-701-1015", "Y",    "DOSE NOT CHANGED",
  "01-701-1015", "N",    "DOSE NOT CHANGED",
  "01-701-1028", "N",    "DRUG WITHDRAWN"
)

subject_level_flag(
  data = adsl,
  data_long = adae,
  ANY_AESER = AESER == "Y",
  ANY_DRUG_WITHDRAWN = AEACN == "DRUG WITHDRAWN"
)
#> # A tibble: 3 × 4
#>   USUBJID     SEX   ANY_AESER ANY_DRUG_WITHDRAWN
#>   <chr>       <chr> <lgl>     <lgl>             
#> 1 01-701-1015 F     TRUE      FALSE             
#> 2 01-701-1023 M     FALSE     FALSE             
#> 3 01-701-1028 M     FALSE     TRUE