AI Insight
This study analyzed pre-hospital emergency service use (NHS 111 calls and ambulance dispatch) across a UK population of approximately 5 million people, finding that a small proportion of individuals (roughly 4%) accounted for around 20-26% of all contacts. The distribution of service use followed a heavy-tailed, power-law-compatible pattern, a statistical hallmark of complex systems behavior. Patients with mental health-related contacts were consistently more likely to make further contacts with emergency services, regardless of their overall level of use.
Why it matters
These findings suggest that demand management strategies for pre-hospital emergency services must address both individual high-intensity users, especially those with mental health conditions, and systemic factors driving overall demand patterns. Understanding this as a complex system rather than a simple aggregation of individual behaviors may improve the design of interventions aimed at reducing pressure on emergency services.
⚠️ Preprint – Noch nicht peer-reviewed
Dieser Artikel wurde noch nicht von unabhängigen Experten begutachtet. Die Ergebnisse sind vorläufig und sollten mit Vorsicht interpretiert werden.
Background High Intensity Use of urgent medical services by patients is widely recognised in urgent and emergency care. Studies of high intensity use of the emergency department have consistently shown features of complex systems behaviour in addition to highly heterogeneous individual patient characteristics. There have been no comparable studies of prehospital care use. Methods We examined the use of prehospital urgent and emergency services (NHS 111 and ambulance dispatch) using routinely collected data from regional service in the UK (population 5 million). We used a complex systems perspective, to examine (1) distribution of contacts per individual; (2) the temporal stability of service use by individuals and at the whole-system level (3) the distribution of bursts of contacts. Results We analysed data from 847555 individuals who contacted NHS111 and 389550 who contacted the ambulance dispatch service. 35120 (4.2%) individuals who contacted NHS111 had 5 or more contacts with the service over the two-year period and accounted for 290625 (20.1%) of contacts. 16755 (4.3%) individuals had 5 or more ambulance dispatch contact days and accounted for 169085 (25.8%) of contacts. The distribution of contacts per individual showed a monotonic distribution between 5 and over 100 contacts that was heavy tailed and compatible with a power law distribution. At any level of use, patients with one or more mental health related contacts had a greater likelihood of further contact than those without. Conclusion Prehospital emergency service use shows multiple statistical features typical of a complex system. Interventions to manage demand need to consider both individual high intensity users (particularly in relation to their mental health) and the behaviour of the whole system.