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Create an Existence Flag

Source: R/get_flagged_records.R
get_flagged_records.Rd

Create a flag variable for the input dataset which indicates if there exists at least one observation in the input dataset fulfilling a certain condition.

Note: This is a helper function for derive_vars_merged_exist_flag() which inputs this result into derive_vars_merged().

Usage

get_flagged_records(dataset, new_var, condition, filter = NULL)

Arguments

dataset

Input dataset

new_var

New variable

The specified variable is added to the input dataset.

condition

Condition

The condition is evaluated at the dataset (dataset). For all rows where it evaluates as TRUE the new variable is set to 1 in the new column. Otherwise, it is set to 0.

filter

Filter for additional data

Only observations fulfilling the specified condition are taken into account for flagging. If the argument is not specified, all observations are considered.

Permitted Values: a condition

Value

The output dataset is the input dataset filtered by the filter condition and with the variable specified for new_var representing a flag for the condition.

See also

Utilities used within Derivation functions: call_user_fun(), extract_unit(), get_not_mapped(), get_vars_query()

Examples


library(dplyr, warn.conflicts = FALSE)


ae <- tribble(
  ~STUDYID,  ~DOMAIN,  ~USUBJID,    ~AETERM,     ~AEREL,
  "PILOT01",    "AE", "01-1028", "ERYTHEMA", "POSSIBLE",
  "PILOT01",    "AE", "01-1028", "PRURITUS", "PROBABLE",
  "PILOT01",    "AE", "06-1049",  "SYNCOPE", "POSSIBLE",
  "PILOT01",    "AE", "06-1049",  "SYNCOPE", "PROBABLE"
)


get_flagged_records(
  dataset = ae,
  new_var = AERELFL,
  condition = AEREL == "PROBABLE"
) %>%
  select(STUDYID, USUBJID, AERELFL)
#> # A tibble: 4 × 3
#>   STUDYID USUBJID AERELFL
#>   <chr>   <chr>     <dbl>
#> 1 PILOT01 01-1028       0
#> 2 PILOT01 01-1028       1
#> 3 PILOT01 06-1049       0
#> 4 PILOT01 06-1049       1

vs <- tribble(
  ~STUDYID,  ~DOMAIN,  ~USUBJID,      ~VISIT, ~VSTESTCD, ~VSSTRESN, ~VSBLFL,
  "PILOT01",    "VS", "01-1028", "SCREENING",  "HEIGHT",     177.8,      NA,
  "PILOT01",    "VS", "01-1028", "SCREENING",  "WEIGHT",     98.88,      NA,
  "PILOT01",    "VS", "01-1028",  "BASELINE",  "WEIGHT",     99.34,     "Y",
  "PILOT01",    "VS", "01-1028",    "WEEK 4",  "WEIGHT",     98.88,      NA,
  "PILOT01",    "VS", "04-1127", "SCREENING",  "HEIGHT",     165.1,      NA,
  "PILOT01",    "VS", "04-1127", "SCREENING",  "WEIGHT",     42.87,      NA,
  "PILOT01",    "VS", "04-1127",  "BASELINE",  "WEIGHT",     41.05,     "Y",
  "PILOT01",    "VS", "04-1127",    "WEEK 4",  "WEIGHT",     41.73,      NA,
  "PILOT01",    "VS", "06-1049", "SCREENING",  "HEIGHT",    167.64,      NA,
  "PILOT01",    "VS", "06-1049", "SCREENING",  "WEIGHT",     57.61,      NA,
  "PILOT01",    "VS", "06-1049",  "BASELINE",  "WEIGHT",     57.83,     "Y",
  "PILOT01",    "VS", "06-1049",    "WEEK 4",  "WEIGHT",     58.97,      NA
)
get_flagged_records(
  dataset = vs,
  new_var = WTBLHIFL,
  condition = VSSTRESN > 90,
  filter = VSTESTCD == "WEIGHT" & VSBLFL == "Y"
) %>%
  select(STUDYID, USUBJID, WTBLHIFL)
#> # A tibble: 3 × 3
#>   STUDYID USUBJID WTBLHIFL
#>   <chr>   <chr>      <dbl>
#> 1 PILOT01 01-1028        1
#> 2 PILOT01 04-1127        0
#> 3 PILOT01 06-1049        0