padCohortStart: Add days to cohort start

In CohortConstructor: Build and Manipulate Study Cohorts Using a Common Data Model

Add days to cohort start

Description

padCohortStart() Adds (or subtracts) a certain number of days to the cohort start date. Note:

• If the days added means that cohort start would be after cohort end then the cohort entry will be dropped.

• If subtracting day means that cohort start would be before observation period start then the cohort entry will be dropped.

Usage

padCohortStart(
  cohort,
  days,
  collapse = TRUE,
  padObservation = TRUE,
  cohortId = NULL,
  name = tableName(cohort),
  .softValidation = FALSE
)

Arguments

cohort	A cohort table in a cdm reference.
days	Integer with the number of days to add or name of a column (that must be numeric) to add.
collapse	Whether to collapse the overlapping records (TRUE) or drop the records that have an ongoing prior record.
padObservation	Whether to pad observations if they are outside observation_period (TRUE) or drop the records if they are outside observation_period (FALSE)
cohortId	Vector identifying which cohorts to modify (cohort_definition_id or cohort_name). If NULL, all cohorts will be used; otherwise, only the specified cohorts will be modified, and the rest will remain unchanged.
name	Name of the new cohort table created in the cdm object.
.softValidation	Whether to perform a soft validation of consistency. If set to FALSE four additional checks will be performed: 1) a check that cohort end date is not before cohort start date, 2) a check that there are no missing values in required columns, 3) a check that cohort duration is all within observation period, and 4) that there are no overlapping cohort entries

Value

Cohort table

Examples

library(CohortConstructor)
cdm <- mockCohortConstructor()
# add 10 days to each cohort entry
cdm$cohort1 |>
  padCohortStart(days = 10)

CohortConstructor documentation built on June 8, 2025, 12:49 p.m.