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A package for aggregating and analysing information on clinical studies, and for obtaining documents, from public registers

1 - Database connection

Package ctrdata retrieves trial information and stores it in a database collection. Therefore, a database connection object has to be given to parameter con for several ctrdata functions. The connection object is built using nodbi which allows to use different database backends. Specifying a collection = "<my collection's name>" is necessary for package ctrdata. A connection object (here called dbc) is created in almost identical ways for these supported backends:

DatabaseConnection object
MongoDBdbc <- nodbi::src_mongo(db = "my_db", collection = "my_coll")
DuckDBdbc <- nodbi::src_duckdb(dbname = "my_db", collection = "my_coll")
SQLitedbc <- nodbi::src_sqlite(dbname = "my_db", collection = "my_coll")
PostgreSQLdbc <- nodbi::src_postgres(dbname = "my_db"); dbc[["collection"]] <- "my_coll"

2 - Operate on a clinical trial register

ctrOpenSearchPagesInBrowser, ctrLoadQueryIntoDb (load trial records into database collection); see ctrdata-registers for details on registers and how to search.

3 - Get a data frame from the database collection

ctrShowOneTrial (show widget to explore structure, fields and data of a trial), dbFindFields (find names of fields of interest in trial records in a collection), dbGetFieldsIntoDf (create a data frame with fields of interest from collection), dbFindIdsUniqueTrials (get de-duplicated identifiers of clinical trials' records to subset a data frame).

4 - Operate on a data frame with trial information

dfTrials2Long (convert fields with nested elements into long format), dfName2Value (get values for variable(s) of interest).

Author

Ralf Herold ralf.herold@mailbox.org