Definitions of Capacity and Demand | Urgent & Emergency Care Wait Time Standards

Definitions for Capacity and Demand

Term	Definition
Live / real time information	This is not a technical definition (see Non-functional Requirements for response time requirements). Whenever the word live is suffixed to an operational measure, for example live wait time or real time demand, it is meant to represent that the data item is real-time (or as close as possible to) from the point of view of the user receiving the information. For this reason, in this project live and real time are defined using tolerances given by the users during research activities. Live or real time, in this case 30 minutes (or less), is measured from timestamp at source (the service where the patient is presenting) to when displayed or shared with patient. Live wait times are measured from source to patient.
Demand	The requirement for service, usually measured at the start of a clinical pathway and using signposting and referring services as a source. For example, number of people calling NHS 111.
Capacity	Service availability to deliver care. For example, number of appointment slots available on Mondays.
Delay	This is the basic concept underlying concept for Wait Time, Delay in transfer of care, Handover time, Turnaround time, etc. It is also, by definition, a queue in the system. See Delayed transfers of care: a quick guide.
Throughput	Number of patients attending a service (incoming flow) vs. number of patients leaving (i.e. being discharged) the same service. Check definitions for Patient Flow and Throughput.
Wait Time (Display)	It is a delay in receiving care viewed from the perspective of the patient. It can be modelled as a pause in the patient journey (as no care is being received at this point).
Delay in transfer of care	Time measured from the perspective of the service delivering care, it is a delay in starting the handover process. From the patient’s perspective, the journey has not been interrupted. See also Handover time.
Handover time	The time taken to complete the handover process. The time lapsed between a service requesting the handover and the process actually taken place is referred to as a Delay in transfer of care.
Turnaround time	Time needed to make an ambulance available for the next episode of care. Definition of this metric can be found here.
Patient flow	Process-oriented view of the patient journey through the healthcare service. Improving patient flow. The term flow describes the progressive movement of people, equipment and information through a sequence of processes. In healthcare, the term generally denotes the flow of patients between staff, departments and organisations along a pathway of care.
Patient journey	Person-oriented view of the pathway. From the patient’s perspective, the journey is defined by all the services involved in delivering care, in other words, the services forming the care pathway.