dfTrials2Long

The function works with procotol- and results- related information.
It converts lists and other values that are in a data frame returned
by dbGetFieldsIntoDf into individual rows of a long data frame.
From the resulting long data frame, values of interest can be selected
using dfName2Value.
The function is particularly useful for fields with complex content,
such as node field "<code>clinical_results</code>" from EUCTR, for which
dbGetFieldsIntoDf returns as a multiply nested list and for
which this function then converts every observation of every (leaf)
field into a row of its own.

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' ('CTGOV', using the classic interface at
<https://classic.clinicaltrials.gov/>, and 'CTGOV2', using the
current interface at <https://www.clinicaltrials.gov/>), 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').
All documents in registers associated with trials can also be downloaded.
Other functions 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 meta-analysis and trend-analysis of
the design and conduct as well as of the results of clinical trials.

Ralf Herold

ctrdata

Retrieve and Analyze Clinical Trials in Public Registers

dfTrials2Long function

<dl><dt>df</dt>
<dd>Data frame (or tibble) with columns including
the trial identifier (<code>_id</code>) and
one or more variables as obtained from
dbGetFieldsIntoDf</dd></dl>

Arguments

Convert data frame with trial records into long format — dfTrials2Long

<dl>

<dt>df</dt>
<dd>Data frame (or tibble) with columns including
the trial identifier (<code>_id</code>) and
one or more variables as obtained from
dbGetFieldsIntoDf</dd>

</dl>

dfTrials2Long: Convert data frame with trial records into long format

Description

Usage

Value

Arguments

Examples