REDCap has a long list of API endpoints (types of information) that
can be extracted. Here we list the most important ones (in our opinion),
and give an indication of how to access them via
redcaptools.
redcap_export_tbl is the real workhorse of
redcaptools. It is the primary interface to the API. Other
export functions all wrap this in some form.
The most important is arguably the record endpoint,
which allows you to download the actual data.
Without the data dictionary, it’s often difficult to tell what a variable is.
This is one of the three pieces of metadata downloaded by default by
the redcap_export_meta function.
The data dictionary is also really important for the functions which
format and label variables (e.g. redcap_prep,
singlechoice_ops, singlechoice_factor and
co)
The list of eCRFs (known as instruments in REDCap). This provides a link between the data dictionary and the instrument labels as seen in REDCap.
The list of events (visits)
This is one of the three pieces of metadata downloaded by the
redcap_export_meta function.
This endpoint lists which forms are available in which events/visits.
This is one of the three pieces of metadata downloaded by the
redcap_export_meta function.
This is of use when repeated forms and/or events are used.
Arms allow different groups of participants (records) to have
different visit structures. In the export, they are visible in the
redcap_event_name variable as
e.g. form_name_arm_1. The arm API endpoint
allows one to retrieve the labels for the arms.