Few workforce debates in recent NHS history have generated as much professional anger, political manoeuvring, and genuine patient safety concern as the controversy surrounding physician associates. What began as a pragmatic response to workforce shortages in the early 2000s has, by 2026, become a flashpoint for fundamental questions about clinical competence, regulatory legitimacy, and the boundaries of medical practice. For candidates preparing for the AKT and the Medical Licensing Assessment, the physician associate question is not merely a policy curiosity. It sits at the intersection of clinical governance, patient safety, informed consent, and multidisciplinary teamworking - all domains that the MLA curriculum explicitly tests.
The publication of the Leng Review in July 2025, and the government's acceptance of all eighteen of its recommendations, marked a decisive turning point. But it has not ended the debate. If anything, the review has sharpened the lines of disagreement between those who see physician associates - now officially renamed physician assistants - as a pragmatic necessity, and those who view the entire programme as an inadequately evidenced experiment conducted on an unsuspecting public.
The Origins and Expansion of the Physician Associate Role
Physician associates were introduced into the NHS in the early 2000s, modelled loosely on the physician assistant role that has existed in United States healthcare since the 1960s. In the UK model, PAs are graduates, typically holding a biomedical science degree, who complete a two-year postgraduate training programme. They do not hold a medical degree, cannot independently prescribe, and cannot order ionising radiation. The role was conceived as a supportive one: PAs would assist doctors, take histories, perform examinations, and manage straightforward clinical presentations under supervision, thereby freeing doctors to manage more complex cases.
For the first decade, expansion was modest and largely uncontroversial. The problems began as numbers grew and, critically, as the scope of practice in many settings expanded informally and without adequate governance. The 2023 NHS Long Term Workforce Plan set a target of 10,000 PAs by 2035, and this ambition - perceived by many in the medical profession as prioritising cost savings over clinical safety - catalysed widespread opposition. By September 2024, over 3,500 full-time equivalent PAs were working across primary and secondary care in England, with approximately 2,000 deployed in general practice through the Additional Roles Reimbursement Scheme.
A series of high-profile patient safety incidents intensified public and professional concern. Cases reported in the media included patients who believed they had been seen by a doctor but had in fact been assessed by a PA, with serious diagnoses - including aortic dissection and pulmonary embolism - reportedly missed or delayed. The BMA collected over 600 reports from doctors and medical students between November 2023 and February 2025 documenting concerns about PAs working beyond their competence, seeing undifferentiated patients without adequate supervision, and being placed on medical rotas in ways that blurred the distinction between doctors and associates.
The Evidence Base: What Do We Actually Know?
The most rigorous attempt to synthesise the UK evidence was the rapid systematic review published in The BMJ in March 2025 by Professors Trisha Greenhalgh of the University of Oxford and Martin McKee of the London School of Hygiene and Tropical Medicine (DOI: 10.1136/bmj-2025-084613). Their review, which searched PubMed, CINAHL, and the Cochrane Library for studies published between 2015 and January 2025, identified 52 eligible papers - 48 on physician associates and just four on anaesthesia associates. Of these, only 29 met their inclusion criteria for trustworthiness, generalisability, and relevance to current UK policy, and all 29 originated from England.
The findings were striking in their sparsity. Only one study, involving just four physician associates, included any direct assessment of clinical competence by a supervising doctor. No studies examined safety incidents. No studies assessed prescribing safety. The evidence on anaesthesia associates was even thinner: no study directly assessed their clinical performance. Greenhalgh and McKee concluded that the absence of reported safety incidents in such small, methodologically limited studies should not be taken as evidence of safety - rather, it reflected a failure to conduct the right kind of research.
There was some preliminary evidence suggesting that PAs could usefully support hospital ward teams and emergency departments when deployed in carefully circumscribed, lower-risk roles under close supervision. In primary care, however, where clinical presentations are undifferentiated and diagnostic uncertainty is the norm, the evidence offered no reassurance. Staff concerns about PAs managing complex or undifferentiated patients were a consistent finding across multiple studies. Patient views were generally positive or neutral, though a recurring theme was that many patients were unaware they had been seen by a PA rather than a doctor - raising serious questions about informed consent.
The Leng Review: A Pragmatic Reset
In November 2024, Health Secretary Wes Streeting commissioned Professor Gillian Leng CBE to conduct an independent review of the PA and AA roles. The review, published on 16 July 2025, drew on an independent literature review, a purpose-built survey of 8,558 frontline staff, patient focus groups, clinical interviews, and site visits. Its 18 recommendations were accepted by the government in full on the day of publication.
The headline recommendations included renaming physician associates as physician assistants to reflect the supportive, complementary nature of the role; a requirement that physician assistants should not see undifferentiated patients except within clearly defined national clinical protocols; a stipulation that newly qualified physician assistants must gain at least two years of experience in secondary care before working in primary care or mental health settings; mandatory direct supervision by a named doctor; the introduction of standardised national uniforms, lanyards, and badges to distinguish physician assistants from doctors; and the establishment of a permanent faculty to provide professional leadership and credentialling standards.
The review also opened a pathway - contingent on further training and credentialling - for physician assistants to eventually prescribe and order non-ionising radiation, and to progress to an advanced physician assistant grade. For anaesthesia associates, the review recommended renaming them physician assistants in anaesthesia and continuing to work within the boundaries set by the Royal College of Anaesthetists, with an ongoing national safety audit to provide assurance.
Divided Opinions: The Professional Response
The Leng Review drew markedly different reactions across the profession. The Royal College of Physicians described it as a thoughtful and thorough analysis of a complex issue, welcoming the emphasis on national consistency and patient safety. The Royal College of Emergency Medicine accepted the recommendations but reaffirmed its position that there should be no expansion of PA roles in emergency medicine, that PAs cannot replace doctors or advanced clinical practitioners, and that undifferentiated patients must be seen by a clinician of appropriate seniority before being allocated to a PA.
The BMA was sharply critical. It characterised the review as an inadequate response to what it termed a patient safety scandal, arguing that the recommendations fell short by not imposing a nationally agreed scope of practice. The BMA had previously conducted its own survey of over 18,000 doctors, finding that 87 per cent reported that the way PAs currently work sometimes or always poses a risk to patient safety. In a separate 2025 survey submitted to the Leng Review, 95 per cent of doctors supported national standards for PA duties, and 77 per cent doubted that NHS organisations could deploy PAs safely, particularly in unsupervised roles.
On the other side of the debate, the trade union UNISON argued that PAs were being disproportionately scapegoated when the real problem was chronic underfunding, overstretched staff, and soaring demand. The PA trade union UMAPs mounted legal proceedings challenging the Leng Review recommendations, and by August 2025 had secured what Pulse Today reported as a pause on NHS England updating the PCN DES specification to reflect the review's restrictions - meaning that the formal job description for ARRS-funded PAs in primary care continued to permit seeing undifferentiated patients even after the government had accepted the review's recommendation against this.
Regulatory Complexity and Ongoing Legal Challenge
The regulatory landscape adds further layers of controversy. GMC regulation of PAs and AAs began in December 2024, with a transition period running to December 2026, by which time registration becomes a legal requirement. The BMA challenged the GMC's use of the umbrella term medical professionals to describe both doctors and associates, arguing that this implied equivalence in training and competence. The High Court dismissed this challenge in April 2025, with Mrs Justice Lambert noting that shared standards were logical given the overlap in work undertaken. However, Anaesthetists United brought a separate judicial review against the GMC on similar grounds, heard in May and June 2025, with judgment expected before the end of that summer.
This regulatory entanglement matters because it speaks to a fundamental tension: if PAs are regulated by the same body as doctors, under overlapping standards, patients and employers may reasonably, but incorrectly, infer a degree of clinical equivalence that does not exist. The Leng Review explicitly acknowledged this concern, recommending that GMC requirements for physician assistants should be presented separately from those for doctors to reinforce the differences in role.
What Does the Evidence Actually Support?
A balanced reading of the available evidence suggests several conclusions. First, the evidence base for PA safety and effectiveness in the UK is genuinely sparse, as Greenhalgh and McKee documented. The rapid expansion of the role outpaced the research needed to underpin it, and the resulting policy was built more on workforce expediency than on clinical evidence. Second, there is reasonable preliminary evidence that PAs can contribute usefully to structured, supervised hospital teams in lower-risk roles - but no convincing evidence that they add value in primary care, where the clinical terrain of undifferentiated presentation demands a depth of training that a two-year postgraduate programme does not provide. Third, the concerns raised by the medical profession are not parochial protectionism; they reflect genuine clinical and ethical anxieties about patient safety, informed consent, and diagnostic accuracy that the published evidence has done nothing to allay.
At the same time, the reality of NHS workforce pressures is undeniable. Over 3,500 PAs are already employed, many of them dedicated professionals who entered the role in good faith. The Leng Review represents an attempt to find a pragmatic middle ground: retaining the workforce but constraining its scope, improving supervision, and investing in the evidence and governance structures that should have preceded the expansion. Whether this compromise proves sufficient - or whether the ongoing legal challenges and professional opposition will force a more radical reckoning - remains to be seen.
Relevance to the AKT and MLA
For candidates preparing for the AKT and the Medical Licensing Assessment, this controversy touches on several examinable domains. Questions on clinical governance may test understanding of scope of practice, the responsibilities of supervising clinicians, and the structures that ensure patient safety in multidisciplinary teams. The principle that undifferentiated patients in primary care require assessment by a clinician with adequate diagnostic training is directly relevant to questions on clinical reasoning, differential diagnosis, and safe consultation practice. Informed consent - and specifically whether a patient understood the qualifications of the clinician assessing them - is a recurrent theme in medical ethics and law, and the PA debate offers a contemporary case study.
Candidates should also be aware of the regulatory framework: the GMC's assumption of PA regulation from December 2024, the statutory registration deadline of December 2026, and the distinctions between the regulatory requirements for doctors and those for physician assistants. Understanding the Leng Review's key recommendations - particularly around not seeing undifferentiated patients, mandatory secondary care experience before primary care deployment, and the requirement for named supervision - is relevant not only to governance questions but to the broader understanding of safe and effective teamworking that the MLA expects of newly licensed doctors.
Key References and Further Reading
Greenhalgh T, McKee M. Physician associates and anaesthetic associates in UK: rapid systematic review of recent UK based research. BMJ. 2025;389:e084613. https://doi.org/10.1136/bmj-2025-084613
The Leng Review: An independent review into physician associate and anaesthesia associate professions. Department of Health and Social Care. July 2025. https://www.gov.uk/government/publications/independent-review-of-the-physician-associate-and-anaesthesia-associate-roles-final-report/the-leng-review-an-independent-review-into-physician-associate-and-anaesthesia-associate-professions
McKee M, Vaughan LK, Russo G. A contentious intervention to support the medical workforce: a case study of the policy of introducing physician associates in the United Kingdom. Human Resources for Health. 2025;23:4. https://doi.org/10.1186/s12960-024-00966-1
NHS England. Response to the recommendations of the Independent Review of Physician Associates and Anaesthesia Associates (the Leng Review). July 2025. https://www.england.nhs.uk/long-read/response-to-the-recommendations-of-the-independent-review-of-physician-associates-and-anaesthesia-associates-the-leng-review-2
BMA. BMA publishes shocking testimony from doctors of patient safety concerns caused by the NHS's use of PAs and AAs. March 2025. https://www.bma.org.uk/bma-media-centre/bma-publishes-shocking-testimony-from-doctors-of-patient-safety-concerns-caused-by-the-nhs-s-use-of-pas-and-aas
Royal College of Emergency Medicine. RCEM response to the Leng Review on PAs. October 2025. https://rcem.ac.uk/news/rcem-publishes-its-response-to-the-leng-review-on-pas/
RCGP. New RCGP guidance sets clear limits on Physician Associate roles. 2024. https://www.rcgp.org.uk
Written Statement to Parliament: The Independent Review of Physician Associates and Anaesthesia Associates in England. July 2025. https://questions-statements.parliament.uk/written-statements/detail/2025-07-16/hcws830