requirePriorObservation {CohortConstructor}

Restrict cohort on prior observation

Description

requirePriorObservation() filters cohort records, keeping only records where individuals satisfy the specified prior observation criteria.

Usage

requirePriorObservation(
  cohort,
  minPriorObservation,
  cohortId = NULL,
  indexDate = "cohort_start_date",
  name = tableName(cohort)
)

Arguments

cohort

A cohort table in a cdm reference.

minPriorObservation

A minimum number of prior observation days in the database.

cohortId

IDs of the cohorts to modify. If NULL, all cohorts will be used; otherwise, only the specified cohorts will be modified, and the rest will remain unchanged.

indexDate

Variable in cohort that contains the date to compute the demographics characteristics on which to restrict on.

name

Name of the new cohort with the prior observation restriction.

Value

The cohort table with only records for individuals satisfying the prior observation requirement

Examples

library(CohortConstructor)
cdm <- mockCohortConstructor()
cdm$cohort1 |>
  requirePriorObservation(indexDate = "cohort_start_date",
                          minPriorObservation = 365)