Background Primary care focused unscheduled care centres (UCC) co-located with major EDs have been proposed as a solution to the rise in ED attendances. They aim to reduce the burden of primary care patients attending the ED, hence reducing crowding, waits and cost.

This review analysed available literature in the context of the impact of general practitioner (GP) delivered, hospital-based (adjacent or within the ED) unscheduled care services on process outcomes, cost-effectiveness and patient satisfaction.

Methods A narrative literature review of studies published between 1980 and 2015 was undertaken. All study types were reviewed and included if they reported a service model using hospital-based primary care clinicians with a control consisting of standard ED clinician-delivered care.

Results The electronic searches yielded 7544 citations, with 20 records used in the review. These were grouped into three main themes: process outcomes, cost-effectiveness and satisfaction. A paradoxical increase in attendances has been described, which is likely to be attributable to provider-induced demand, and the evidence for improved throughput is poor. Marginal savings may be realised per patient, but this is likely to be overshadowed by the overall cost of introducing a new service.

Conclusions There is little evidence to support the implementation of co-located UCC models. A robust evaluation of proposed models is needed to inform future policy.