This dataset contains structured records of NHS 111 calls handled by Yorkshire Ambulance Service. It includes information on call timing, presenting symptoms, triage outcomes, referral pathways, and additional metadata reflecting the structure of the legacy call handling system in use at the time.

This dataset should only be used for studies covering NHS 111 contacts between April 2011 and March 2017. It predates the introduction of the NHS 111 Minimum Data Set and differs structurally from later data extracts. Researchers should not attempt to combine it with post-2017 data unless there is a clear justification and defined harmonisation plan.