merge.Cov: Merge events with covariates

In qPharmetra/PMDatR: Pharmacometric Data Management in R

Merge events with covariates

Description

Merge events with covariates

Usage

## S3 method for class 'Cov'
merge(events.df, covs.l)

Arguments

events.df	The events dataframe into which to merge the covariates
covs.l	A list of covariate tbl_df dataframes to merge into events.df

Details

The events dataframe is merged with each tbl_df according to the keys for the covariates. Each member of covs.l may have its own keys, which are stored in the groups property for the object. Hence, merging can be controlled by changing the grouping of the covariate dataframes using dplyr::group_by.

By default a left join is performed, so all records in events.df are preserved. Unmatched key values in the covariate data will result in NA in the covariate column. Covariate data with unmatched keys will be silently dropped. For example, if merging covariates by ID and VISIT, if the SCREENING visit was not included in the covariate data then observations or doses occurring in (or associated with) the SCREENING VISIT will have NA values for the covariates. Conversely, if the Follow-up VISIT is not present in the event data, no covariate data is present in the result for the Follow-up visit. This ensures that new rows are not added that would not have the correct variables (TIME, AMT, DV, EVID, etc.) set.

To use other types of joins, set a join_type attribute on the data_frame objects in covs.l. The available options are: left, right, inner, full. Any other value will default to a left join.

Value

A tbl_df object with the merged data

qPharmetra/PMDatR documentation built on April 7, 2024, 5:42 p.m.