dfMergeVariablesRelevel

Merge variables in a data frame such as returned by dbGetFieldsIntoDf
into a new variable, and optionally also map its values to new levels.
See ctrdata-trial-concepts for pre-defined cross-register concepts
that are already implemented based on merging fields from different
registers and calculating a new field.

A system for querying, retrieving and analyzing
protocol- and results-related information on clinical trials from
four public registers, the 'European Union Clinical Trials Register'
('EUCTR', <https://www.clinicaltrialsregister.eu/>),
'ClinicalTrials.gov' (<https://clinicaltrials.gov/> and also
translating queries the retired classic interface), the
'ISRCTN' (<http://www.isrctn.com/>) and the
'European Union Clinical Trials Information System'
('CTIS', <https://euclinicaltrials.eu/>).
Trial information is downloaded, converted and stored in a database
('PostgreSQL', 'SQLite', 'DuckDB' or 'MongoDB'; via package 'nodbi').
Protocols, statistical analysis plans, informed consent sheets and other
documents in registers associated with trials can also be downloaded.
Other functions implement trial concepts canonically across registers,
identify deduplicated records, easily find and extract variables
(fields) of interest even from complex nested data as used by the
registers, merge variables and update queries.
The package can be used for monitoring, meta- and trend-analysis of
the design and conduct as well as of the results of clinical trials
across registers.

Ralf Herold

ctrdata

Retrieve and Analyze Clinical Trials Data from Public Registers

dfMergeVariablesRelevel function

<dl><dt>df</dt>
<dd>A <a href="/link/data.frame?package=ctrdata&version=1.22.0" data-mini-rdoc="ctrdata::data.frame">data.frame</a> with the variables (columns) to be merged into
one vector.</dd>
<dt>colnames</dt>
<dd>A vector of names of columns in `df` that hold the variables
to be merged, or a selection of columns as per <code><a href="https://dplyr.tidyverse.org/reference/select.html">select</a></code>.</dd>
<dt>levelslist</dt>
<dd>A names list with one slice each for a new value to be
used for a vector of old values (optional).</dd></dl>

Arguments

Merge variables, keeping type, and optionally relevel factors — dfMergeVariablesRelevel

<dl>

<dt>df</dt>
<dd>A <a href='https://rdrr.io/r/base/data.frame.html'>data.frame</a> with the variables (columns) to be merged into
one vector.</dd>


<dt>colnames</dt>
<dd>A vector of names of columns in `df` that hold the variables
to be merged, or a selection of columns as per <code><a href='https://dplyr.tidyverse.org/reference/select.html'>select</a></code>.</dd>


<dt>levelslist</dt>
<dd>A names list with one slice each for a new value to be
used for a vector of old values (optional).</dd>

</dl>

dfMergeVariablesRelevel: Merge variables, keeping type, and optionally relevel factors

Description

Usage

Value

Arguments

Examples