GP access to radiology

National Guideline Centre (UK)

Chapter 8GP access to radiology

8. Primary care access to radiology

8.1. Introduction

Diagnostic radiology plays an important role in the diagnosis and management of patients presenting with an acute medical emergency (AME). This can range from simple imaging, such as plain x-ray - chest x-ray or abdominal x-ray, to more specialist tests such as computerised tomography (CT), magnetic resonance imaging (MRI), and ultrasound (US) imaging. There is a strategic drive in the United Kingdom to reduce emergency referrals to hospitals; however, the role of such investigations both in terms of access and same day reporting in a GP setting remains unclear.

While it may be accepted that more specialist tests should be restricted to a hospital setting, there may be a more specific role for plain x-ray radiology, for example, in patients presenting to a GP with a sub-acute breathing problem such as a chest infection, exacerbation of chronic obstructive airways disease or exacerbation of asthma, the role of plain x-ray radiology and reassurance of a normal chest x-ray may avoid unnecessary referral to hospital.

8.2. Review question: Does GP access to radiology with same day results improve outcomes?

For full details see review protocol in Appendix A.

Table 1

PICO characteristics of review question.

8.3. Clinical evidence

No relevant clinical studies comparing GP access to same day radiological investigations with same day results to GP access to radiology without same day results were identified.

8.4. Economic evidence

Published literature

No relevant economic evaluations were identified.

See also the economic article selection flow chart in Appendix C.

The unit costs of GP visits, diagnostic tests and relevant hospital admissions or stays were presented to the committee (see Chapter 41 Appendix I).

8.5. Evidence statements

Clinical

No evidence identified.

Economic

No evidence identified.

8.6. Recommendations and link to evidence

Table

The guideline committee considered 6 outcomes critical for inclusion in this review: mortality, avoidable adverse events, patient and/or carer satisfaction, quality of life, ED attendance and admission to hospital. The outcome laboratory/diagnostic turnaround (more...)

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Appendices

Appendix A. Review protocol

Table 2

Review protocol: GP access to radiology.

Appendix B. Clinical article selection

Figure 1Flow chart of clinical article selection for the review of GP access to radiology

Appendix C. Forest plots

No studies were included.

Appendix D. Clinical evidence tables

No studies were included.

Appendix E. Economic evidence tables

No studies were included.

Appendix F. GRADE tables

No studies were included.

Appendix G. Excluded clinical studies

Table 3

Studies excluded from the clinical review.

Appendix H. Excluded economic studies

No studies were excluded.

Publication Details

Copyright

Publisher

National Institute for Health and Care Excellence (NICE), London

NLM Citation

National Guideline Centre (UK). Emergency and acute medical care in over 16s: service delivery and organisation. London: National Institute for Health and Care Excellence (NICE); 2018 Mar. (NICE Guideline, No. 94.) Chapter 8, GP access to radiology.

Table 1PICO characteristics of review question

Population	Adults and young people (16 years and over) with a suspected or confirmed AME or at risk of an AME.
Intervention	GP access to same day radiological investigations (plain x-ray and ultrasound) with same day results.
Comparison	GP access to radiology (plain x-ray and ultrasound) without same day results.
Outcomes	Mortality (CRITICAL) Avoidable adverse events (including delay in diagnosis and treatment, misdiagnosis) (CRITICAL) Quality of life (CRITICAL) Patient and/or carer satisfaction (CRITICAL) Lab or Diagnostic turn around for result to GP (IMPORTANT) ED attendance (CRITICAL) Admissions (CRITICAL)
Study design	Systematic reviews (SRs) of RCTs, RCTs, observational studies only to be included if no relevant SRs or RCTs are identified.

Recommendation	-
Research recommendation	RR5. What is the clinical and cost effectiveness of providing GPs with access to plain X-ray radiology or ultrasound with same day results?
Relative values of different outcomes	The guideline committee considered 6 outcomes critical for inclusion in this review: mortality, avoidable adverse events, patient and/or carer satisfaction, quality of life, ED attendance and admission to hospital. The outcome laboratory/diagnostic turnaround for result to a GP was considered important.
Trade-off between benefits and harms	No evidence was identified which compared GP access to same day radiology or ultrasound results with not receiving results the same day. The committee discussed the absence of evidence and decided to develop a research recommendation. The committee noted that, although this is not current practice across the country, there was the potential for improvement in patient care and outcomes from the availability of same day plain x-ray radiology and ultrasound for a specific subset of patients. It may lead to a decrease in ED admissions and earlier diagnosis. In turn, earlier diagnosis could mean quicker treatment and improved patient outcomes, including patient and/or carer satisfaction. Further research would be needed to evaluate this. This could include patients, such as those with asthma, presenting with acute chest pain and the need to rule out a small pneumothorax. The committee accepted that, in general, patients who might benefit from same day results from radiological investigations could be those who might also require specialist investigation or admission to hospital, as opposed to management within primary care; whilst patients with non-acute illness may not require radiology results on the same day.
Trade-off between net effects and costs	No relevant economic evaluations were identified. The unit costs of GP visits, diagnostic tests and relevant hospital admissions or stays were presented to the committee (see Chapter 41 Appendix I). The costs, effectiveness and cost-effectiveness of same day results might be influenced by the equipment used and the type of staff (including the ratio of radiologists to radiographers used in reporting results), Without effectiveness evidence, the committee were unable to assess the cost-effectiveness of same day results and therefore a research recommendation was made.
Quality of evidence	No evidence was identified which compared same day GP access to diagnostic radiology results compared to not receiving results on the same day. The committee discussed the absence of evidence and used consensus to develop a research recommendation.
Other considerations	The committee focused the research recommendation on plain x-ray radiology and ultrasound as these investigations were most likely to be of benefit within the community. Ultrasound is included in this recommendation to reflect its growing use in rapid diagnosis, for example, to rule out a pleural effusion. The current approach is for GPs to refer patients to the ED or an AMU if they need same day plain x-ray radiography or ultrasound. Patients would likely prefer rapid diagnosis and management to reduce uncertainty. It would be beneficial to patients to not have to transit through the emergency department to access investigations, particularly to those who are frail or elderly. The group decided not to include more invasive radiological investigations (such as CTPA) within the research recommendation as such patients would likely need specialist review and expert interpretation of results. The committee noted that there were likely to be logistical and staffing difficulties in the provision of same day plain x-ray radiology and ultrasound results. Increased provision of staff training would be required. The committee also noted that a ‘result’ was more than just the radiological images; expert interpretation would also be required for investigations which lay outside the expertise of individual GPs.

Table 2Review protocol: GP access to radiology

Review question	Does GP access to radiology and ultrasound with same day results improve outcomes?
Guideline condition and its definition	AME. Definition: people with suspected or confirmed acute medical emergencies.
Objectives	To determine if enhanced GP access to radiological and ultrasound investigations improves outcomes.
Review population	Adults and young people (16 years and over) presenting to a GP with a suspected or confirmed AME.
	Line of therapy not an inclusion criterion.
Interventions and comparators: generic/class; specific/drug (All interventions will be compared with each other, unless otherwise stated)	GP access to same day radiological (plain x-ray) and ultrasound (including Doppler) investigations with same day results at weekdays (out of hours) and weekends. GP access to same day radiological (plain x-ray) and ultrasound (including Doppler) investigations without same day results. Standard services- GP access to same day plain x-ray radiology during working hours (weekdays) with same day results.
Outcomes	- Mortality during the study period (Dichotomous) CRITICAL - Avoidable adverse events (including delay in diagnosis and treatment, misdiagnosis) during the study period (Dichotomous) CRITICAL - Quality of life during the study period (Continuous) CRITICAL - ED attendance during the study period (Dichotomous) CRITICAL - Admissions during the study period (Dichotomous) CRITICAL - Patient and/or carer satisfaction during the study period (Dichotomous) CRITICAL - Laboratory or Diagnostic turn around for result to GP during the study period (Dichotomous) (IMPORTANT)
Study design	Systematic reviews (SRs) of RCTs, RCTs, observational studies only to be included if no relevant SRs or RCTs are identified.
Unit of randomisation	Patient GP surgeries/practices.
Crossover study	Not permitted.
Minimum duration of study	Not defined.
Exclusions	None
Subgroup analyses if there is heterogeneity	- Frail elderly (Frail elderly; No frail elderly); Effects may be different in this group.
Search criteria	The databases to be searched are: Medline, Embase, the Cochrane Library Date limits for search: None Language: English only.

Figure 1Flow chart of clinical article selection for the review of GP access to radiology

Table 3Studies excluded from the clinical review

Study	Exclusion reason
Apthorp 1998 ¹	Incorrect interventions. MRI not in protocol
Benamore 2005 ²	Incorrect interventions. CT not in protocol
Blois 2012³	Incorrect comparison (GP screening for abdominal aortic aneurysm versus ultrasound technician)
Bui 2004⁴	1/3 of population under 16 years old.
Bury 1987⁵	Narrative paper
Carey 1989⁶	No outcomes of interest
Castro 2007⁷	Incorrect interventions (retinal digital images)
Chan 1999⁸	Inappropriate comparison
Chaptini 2010⁹	Incorrect interventions (ambulatory cardiac single-photon emission computed tomography)
Collie 1999 ¹⁰	Incorrect interventions. MRI not in protocol
Detar 1960¹¹	Qualitative study
Duncan 2005¹²	Not a comparative study
Durham 1999¹³	Not a comparative study
Farrell 1977¹⁴	Not a comparative study
Fassiadis 2005¹⁵	Incorrect interventions (screening for abdominal aortic aneurysm)
Frohwein 2001¹⁶	Narrative paper
Geary 2007¹⁷	Not review population
Gravil 1998¹⁸	Incorrect comparison (treated in hospital versus treated at home)
Guldbrandt 2015¹⁹	Incorrect population (lung cancer patients)
Haber 1978²⁰	Narrative paper
Hahn 1988²¹	Narrative paper
Halvorsen 1989²²	Incorrect comparison (GP versus radiologist interpretation)
Hammond 2000²³	Narrative
Hawksworth 1951²⁴	Case series
Howard 2005 ²⁵	Incorrect interventions. Neuroimaging not in protocol
Hussain 1999²⁷	Incorrect comparison (comparing images sent via differing transition methods)
Hussain 2004²⁶	No outcomes of interest
Ingeman 2015²⁸	No outcomes of interest
Katerndahl 1982²⁹	Narrative
Kiuru 2002³⁰	Incorrect comparison (GP sending some x-rays to hospital for interpretation versus sending all).
Kuritzky 1987³¹	Incorrect interventions (interpretation of x-rays by GP versus radiologist)
Laerum 2001³²	Narrative
Lahde 2002³³	Not an intervention study
Laine 1998³⁴	Incorrect comparison (comparing ultrasound, clinical exam and radiography)
Laws 2006³⁵	Not a comparative study. No outcomes of interest.
Leiro-fernandez 2014³⁶	Incorrect interventions (system to alert pulmonologists of lung cancer suspicion)
Li 1999³⁷	Incorrect interventions (screening for glaucoma)
Li 2011³⁸	Incorrect interventions (ocular telehealth)
Maurin 2014³⁹	Not review population
Mclain 1985⁴⁰	Inappropriate comparison (GP versus radiologist interpretation)
Merrington 1981⁴¹	Narrative
Miller 2006⁴²	Not a comparative study
Mjolstad 2012⁴³	Inappropriate comparison
Morioka 2007⁴⁴	No outcomes of interest
Olayiwola 2011⁴⁵	Incorrect interventions
Osmond 1977⁴⁶	Narrative
Oswald 1964⁴⁷	Narrative
Oswald 1964⁴⁸	Narrative
Paakkala 1988⁴⁹	Inappropriate comparison (GP versus radiologist interpretation)
Pavlicek 1999⁵⁰	No outcomes of interest
Pickhardt 2006⁵¹	Not a comparative study
Qureshi 2001⁵²	Does not match protocol (diagnostic accuracy of Doppler ultrasound)
Rawson 1965⁵³	Inappropriate comparison (GP versus hospital clinician)
Redmond 2013⁵⁴	Inappropriate comparison (GP versus radiologist interpretation)
Rogers 2010⁵⁵	Narrative paper
Romero-aroca 2010⁵⁶	Incorrect interventions (screening for retinopathy)
Smith 1993⁵⁷	Not a comparative study
Speets 2006⁵⁸	Not a comparative study
Stoddart 1989⁵⁹	Not a comparative study
Strasser 1987A⁶⁰	Unclear when results were received by the GP for control group.
Suramo 2002⁶¹	Incorrect interventions (accuracy of ultrasound scans performed by GPs)
Taylor 2007⁶²	Incorrect interventions (retinopathy screening)
Thomas 2010 ⁶³	Incorrect interventions. CT not in protocol
Verstraete 2008⁶⁴	Incorrect interventions (MRI)
Yates 2016⁷⁰	Incorrect comparison (access versus no access)
Waite 2006⁶⁵	Incorrect interventions (CT)
Weiner 2005⁶⁶	Inappropriate comparison
Whitfield 1973⁶⁷	No outcomes of interest
Wilson 2005⁶⁸	Incorrect interventions (retinal imaging)
Wordsworth 2002⁶⁹	No outcomes of interest