Classifications of Data Elements for a Particular Disease
A data element that can be used in multiple clinical studies, as determined by
a working group of experienced clinical researchers assembled by the NINDS. The
CDEs are content standards that can be applied to various data collection models
and are intended to be dynamic standards that may evolve over time. The goal of
the NINDS CDE Project is to develop standard definitions, code lists, and instructions
for the CDEs so that investigators collect them consistently across studies. CDEs
are the foundation for interoperability among data systems and are a subset of the
universe of all data elements.
A data element that collects essential information applicable to any study, including either those which span across all disease and therapeutic areas or those that are specific to one disease area. The NINDS and their appointed working groups assign the ?Core? classification based on the current clinical research best practices. This term applies to both the General CDEs and the Disease-specific CDEs. In each case, the Core CDEs are a small subset of the available CDEs, where it is anticipated that investigators will need to collect the Core CDEs on any type of study.
Examples of the General Core CDEs include basic demographic information and basic enrollment data collected from all study participants. Examples of Disease-specific Core CDEs for Traumatic Brain Injury studies include CDEs for the Glasgow Outcome Scale Extended.
A logical unit of data, pertaining to information of one kind. A data element
has a name, precise definition, and clear enumerated values (codes) if applicable.
A data element is not necessarily the smallest unit of data; it can be a unique
combination of one or more smaller units. A data element occupies the space provided
by field(s) on a paper/electronic case report form (CRF) or field(s) in a database
An example of a data element is race, where a study participant is asked to choose
which racial category or categories he/she identifies. The race data element generally
consists of the following categories, which are the permissible values/responses:
American Indian or Alaska Native, Asian, Black or African-American, Native Hawaiian
or Other Pacific Islander, and White.
A data element specific to a particular disease or therapeutic area. The NINDS develops disease-specific CDEs for a variety of diseases including, but not
limited to: epilepsy, stroke, Parkinson?s disease, traumatic brain injury, and spinal
A data element that requires further validation, but may fill current gaps in the CDEs and/or substitute for an existing CDE once validation is complete. Such data elements show great promise, but require further validation before they are ready for prime-time use in clinical research studies. They are reasonable to use with the understanding that limited study has been done in the target group.
A data element that can be consistently collected across studies in any disease or therapeutic area. Examples include CDEs collected on the following forms: Demographics, Physical Exam, Informed Consent and Enrollment, and Adverse Events.
The remaining data elements collected by a study that are important to the protocol
but are NOT considered CDEs. In fact, the NINDS recognizes that the most important
variables collected by a study may not be CDEs.
Examples of Protocol-specific data elements are those pertaining to how a specific
intervention being studied is administered or data elements that comprise a new
disease-specific quality of life assessment that is being developed.
A data element which is commonly collected in clinical research studies but whose relevance depends upon the study design (i.e., clinical trial, cohort study, etc.) or type of research involved.
Examples of Supplemental CDEs are the Epilepsy CDEs related to electroencephalogram
(EEG) that are only relevant to epilepsy studies that use EEG for diagnostic purposes
and the Stroke CDEs related to administration of Tissue Plasminogen Activator (tPA) that
are relevant to acute ischemic stroke studies but not relevant to intracerebral
hemorrhage (ICH) studies.
A data element which is essential based on certain conditions or study types in clinical research studies. In most cases, these have been used and validated in the disease area. These data elements are strongly recommended for the specified disease condition, study type or design.