The “Single Source” concept applies the write-once, use-many principle to data gathering for clinical trials using CDA as the key to interoperability in this case study.

The article reports on a pilot implementation done at the Duke Clinical Research Institute that radically streamlined the data-gathering process by eliminating redundant data entry.

On a side note, the authors observed that the highest degree of reuse was not between the clinical trial and the patient chart, but between previous notes in the chart and the note documenting the current encounter.