“Investigations” is a significant section of this hierarchy. It contains investigation results that may lead to a diagnosis of the disorders found elsewhere on the list, but are independently listed. For instance “Electrocardiogram QT prolonged” (an investigation result) may be a sign of “Torsade de Pointes”, a cardiac disorder, but both are listed independently.

Thus, it is important to point out to researchers that they may want to include INVESTIGATION types in their search as well as DISORDERS for a more complete result.