Retrieve and Analyze Clinical Trials in Public Registers
ctrdata: information on clinical trial registers
ctrdata: get started, database connection, function overview
Check and prepare nodbi connection object for ctrdata
Find synonyms of an active substance
Get query details
Load and store register trial information
Open register to show query results or search page
Find names of fields in the database collection
Get identifiers of deduplicated trial records
Create data frame of specified fields from database collection
Show history of queries loaded into a database collection
Merge variables, keeping type, and optionally relevel factors
Get value for variable of interest
Convert data frame with trial records into long format
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'). 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.
Useful links