cal_min_max_date: Calculate minimum and maximum date and time in the data frame

In sdtm.oak: SDTM Data Transformation Engine

Calculate minimum and maximum date and time in the data frame

Description

This function derives the earliest/latest date as ISO8601 datetime

Usage

cal_min_max_date(
  raw_dataset,
  date_variable,
  time_variable,
  val_type = "min",
  date_format,
  time_format
)

Arguments

raw_dataset	Raw source data frame
date_variable	Single character string. Name of the date variable
time_variable	Single character string. Name of the time variable
val_type	Single character string determining whether to look for the earliest or the latest datetime combination. Permitted values: "min", "max". Default to "min".
date_format	Format of source date variable
time_format	Format of source time variable

Value

Data frame with 2 columns: unique patient_number and datetime variable column storing the earliest/latest datetime.

Examples

ex_raw <- tibble::tribble(
  ~patient_number,    ~EX_ST_DT, ~EX_ST_TM,
  "001",           "25-04-2022",   "10:20",
  "001",           "25-04-2022",   "10:15",
  "001",           "25-04-2022",   "10:19",
  "002",           "26-05-2022", "UNK:UNK",
  "002",           "26-05-2022",   "05:59"
)

min <- cal_min_max_date(ex_raw,
  date_variable = "EX_ST_DT",
  time_variable = "EX_ST_TM",
  val_type = "min",
  date_format = "dd-mmm-yyyy",
  time_format = "H:M"
)

max <- cal_min_max_date(ex_raw,
  date_variable = "EX_ST_DT",
  time_variable = "EX_ST_TM",
  val_type = "max",
  date_format = "dd-mmm-yyyy",
  time_format = "H:M"
)

sdtm.oak documentation built on June 9, 2025, 5:10 p.m.