Preexistent Databases Used in Nursing Research for Secondary Analysis Contain

Preexistent databases used in nursing research for secondary analysis contain data of different sorts. What are these?

A) Data collected internally by a healthcare institution for quality assurance or other review of its processes
B) Data collected by unknown people for unknown reasons
C) Data collected by governmental and private agencies, such as insurance companies, external to a healthcare institution
D) Records locked by the courts
E) Data collected by another researcher for a previous study