Summary of developing theories and supporting evidence
| Theory | Context (C)–Mechanism (M)–Outcome (O) configuration | Example of supporting extract | Evidence base |
| 1. Effectiveness of the streaming system | General practitioners (GPs) and emergency department (ED) staff use their own personal experience and expectation (C) when interpreting streaming guidance (M) to influence which patients are streamed to GPs (O). | ‘It seems that patients are difficult to classify (for A&E (ED) or walk-in centre GPs or nurse practitioners) on limited information for several reasons: serious conditions can sound minor, and vice versa; conditions can present in various ways; and complaints can have several underlying causes. ’ 35 | Data to support theory. 4 14 25 32–40 |
| 2a. Traditional general practitioner (GP) role versus emergency clinician role | When GPs working in the ED maintain a ‘traditional role’ using the same approach taken in the primary care setting (M) to treat patients with primary care problems (C), investigations, admissions and process times will reduce (O). However, if GPs adopt an ‘emergency clinician role’ working as another pair of hands (‘going native’) because of their personal interest or experience or because they feel this is the correct way to work in this setting (M), there will be no difference in the rate of investigations and admissions (O). | ‘I guess our emergency medicine approach is we’re looking for something dreadful and a GP approach is very different in that most of the time they know it’s minor stuff or … moderate stuff that is self-limiting and so … they’re looking to find symptomatic relief and how can we get this patient home and away from hospital.’ (Consultant)38
‘Once they start becoming like everyone else then they stop being like a GP and they don’t necessarily work quickly and effectively which is supposed to be the whole benefit of having them there.’ (Consultant)38 | Data to support traditional GP role theory 4 5 25 26 38 39 45–52 Limited data to support ED clinician role theory.38 41 |
| 2b. Extended GP role | GPs in EDs can work in an ‘extended role’ where their skills are directed at specific patient groups including non-urgent paediatric or elderly patients (C), to treat using the usual primary care approach (M), to reduce the use of hospital resources and admissions in these patient groups (O). | ‘ During a 6-month pilot scheme which co-located a primary care GP service in a busy paediatric ED, patients seen during the hours when the GP was available were significantly less likely to be admitted, exceed the 4 hours waiting target or leave before being seen, but more likely to receive antibiotics. ’ 5 | Data to support theory for paediatric patients only. 5 28 43 53 66 |
| 2c. Gatekeeper role | GPs can use their generalist skills and knowledge of community resources (M) to redirect patients presenting with primary care problems (C) out of the ED to alternative primary care services off-site for treatment thereby reducing ED attendances (O). | ‘GPs and nurses based in triage identify patients who could be managed more appropriately in primary care as soon as they enter the ED, and redirect them back to primary care services.’ 70 | Limited data to support theory. 70 71 |
| 3. Patient satisfaction | Patients with primary care problems that present to EDs (C) and are seen by GPs, are more satisfied with the care they receive (O) if the experience exceeds expectation (M), but if they do not perceive any difference in the care they received compared with what they expected (M), there is no difference in satisfaction (O). | ‘There were no significant differences in (patient) satisfaction ratings between the three groups of doctors (GPs, Senior House Officers or Registrars).’ 39 | Limited data to support theory. 26 39 45 47 86–90 |
| 4. Safety implications | In EDs where there are delayed patient transfers to wards or inadequate staffing (C) GPs seeing patients with primary care type problems (M), may not free up ED staff to care for the sickest patients (O). | ‘The attribution of overcrowding in ED to attendance by GP-type patients is simplistic; it does not address how patients are processed within ED or how they are transferred to wards later if required. ’ 46 | Limited data to support theory. 46 93–99 |
| 5. Risk of provider- induced demand | If patients with primary care type problems present to EDs (C) and are streamed to indistinct primary care services, without patient awareness or choice (M), there is no provider-induced demand (O). However, distinct urgent primary care services may offer convenient access to primary care (M), resulting in provider-induced demand (O). | ‘A&E (ED) has not seen any reduction in their patients. If there is a service, patients will use it. You could have three walk-in centres in the city and all three would be used and you may still not see any dropping in A&E (ED) counts.’ (Manager)102 | Data to support theory. 4 27 54–56 80 102–109 |
| 6. Cost-effectiveness | If there is demand for patients with primary care problems presenting to EDs (C), and they are streamed to on-site GPs and managed using a traditional GP approach (M), the service is cost-effective due to fewer referrals, admissions, investigations and better outcomes compared with usual services (O). | ‘Management of patients with primary care needs in the A&E department by GPs reduced costs with no apparent detrimental effect on outcome.’26 | Limited data to support theory. 26 45 51 |