Objective: To model the effectiveness of after-hours general practice (GP) in reducing metropolitan Perth emergency departments' (ED) low acuity patient (LAP) attendances and costs.
Methods: We estimated LAP attendances by comparison of the product of (A) the difference between self-referred and GP-referred ED discharge rates and (B) total self-referred attendances (LAP attendances = A x B). We then compared after-hours ED LAP attendance rates and costs with inner metropolitan "working-week" ED LAP attendance rates and costs, when GP services are maximally available.
Results: Working-week LAP attendances comprised 8.2% (95% CI, 8.0%-8.4%) of inner metropolitan ED attendances. Excess weekend and evening LAP attendances were estimated to comprise 16.5% (95%CI, 15.9%-17.0%) and 4.5% (95%CI, 4.1%-4.9%) of outer and inner metropolitan ED attendances respectively and totalled less than 3.0% of ED costs.
Conclusions: Low acuity patients form a relatively constant, inexpensive proportion of ED workloads. After-hours GP LAP services are unlikely to significantly reduce ED attendances or costs.