Physician associates and anaesthetic associates in UK: rapid systematic review of recent UK based research

Description of dataset and inter-rater reliability

Of approximately 4500 titles on physician associates and 450 on anaesthetic associates, we identified 52 empirical papers (48 on physician associates and four on anaesthetic associates). Of these, 25 studies (written up in 29 papers) met the inclusion standard of a score of at least 1 on all three criteria of trustworthiness, generalisability, and relevance to current UK policy. These are tabulated in clear rows in the supplementary materials on bmj.com. Studies scoring 0 for at least one criterion are tabulated in the shaded rows, showing reasons for exclusion, on bmj.com. The inter-rater reliability for this exercise between the two reviewers was 92.6% (see details on bmj.com).

The papers covered six broad topic categories, summarised in table 1. A more detailed version and additional detail on each topic category are provided in table S1 on bmj.com. The search also identified 13 previous systematic reviews, all but two of which covered mostly non-UK studies (see table S2 on bmj.com).1243 We consider the papers meeting the inclusion standard under each topic category below.

Clinical performance (efficacy and safety)

Published research on the clinical performance of physician associates in the UK (nine papers describing seven studies, of which the papers meeting our inclusion standard are described below) related to only three settings: hospital wards,16 emergency departments,17 and general practice.18192021 We identified no randomised controlled trials directly comparing process or outcome for physician associates versus any other staff group, no studies examining safety incidents, and no studies of the safety of prescribing. We identified no studies directly assessing the efficacy or safety of anaesthetic associates.

All but two of the nine papers in this category were by the same research team (Drennan and colleagues). The work of this team, which is highly cited, seems to have been competently conducted but pertains to a surprisingly small number of physician associates (43 on hospital wards,1622 six in hospital emergency departments,17 and seven in general practice181920); the fieldwork for the primary care component was undertaken more than a decade ago (2011-12), before a substantial increase in NHS pressures, general practice workload, and skill mix.444546

The highest scoring study in this category (Drennan et al, 201916) was a mixed methods case study in medical and surgical wards, using ethnographic observation and a total of 176 interviews with managers, clinicians, and patients. It showed that in participating multidisciplinary teams, physician associates worked mainly on the wards during daytime weekday hours, providing continuity of knowledge about patients’ progress, undertaking tasks (for example, clerking patients, writing discharge summaries), and communicating with patients and across staff groups. Staff described physician associates as contributing to efficiency by smoothing patient flow and aiding communication between medical, nursing, and bed management teams. As one doctor in training put it, “They [PAs] are the lubricant [of the multidisciplinary team] as opposed to, you know, the actual engine” (page 60).22 Physician associates’ local, operational, and system knowledge (perhaps, “knowing the ropes”) was sometimes greater than that of doctors in training who were new to that post, but much of this knowledge was specific to the particular setting. Staff reported that they thought that physician associates were safe (and in particular, safer than locums who did not have local system knowledge) and could recall no safety incidents relating to physician associates; some commented that physician associates were less suited to dealing with clinically complex or risky cases than were doctors in training. Importantly, although the data collection team (made up of nurses and social scientists) observed physician associates to document what tasks they were doing, for these researchers to judge how well they were doing them or to identify safety concerns was not part of the study design.

A non-randomised study in three emergency departments (Halter, 2020b17) analysed a very large number of consultations (n=2890) by a very small number of physician associates (n=6), and the level of missing data was very high (>50%).17 Its primary outcome measure (reattendance at the same healthcare facility with the same complaint within seven days) was not designed to detect or examine safety critical decisions or the impact on other parts of the system (for example, attending a general practitioner or other urgent care facility). The authors showed that physician associates saw a different case mix than doctors (less complex patients; less severe and less urgent illnesses) and took significantly longer to see patients than did doctors. After adjustment for case mix, physician associates ordered significantly more radiographs (adjusted odds ratio 2.7, 95% confidence interval 1.72 to 4.24) and gave more prescriptions, although this difference did not reach statistical significance (adjusted odds ratio 1.35, 0.08 to 23.5). However, as we argue on bmj.com (page 8), the study was underpowered to detect a clinically significant difference between the two staff groups in the primary outcome used (an adequately powered study would need more than five times the number of physician associate consultations). No safety incidents were logged, and a retrospective chart review by senior doctors identified similar levels of omissions and inadequacies in both groups.

Research on the clinical performance of physician associates in UK primary care is very sparse. Drennan and colleagues (2015) used a mixed methods design “to compare outcomes and costs of same-day requested consultations by PAs with those of GPs” (page e344).18 The study was conducted in 2011-12 in 12 general practices in southern England. Six of these employed no physician associates; five employed one physician associate, and one employed two physician associates (that is, seven physician associates in total). All patients attending for same day or urgent appointments with participating physician associates (in practices with physician associates) or general practitioners (in practices without physician associates) in designated sessions over four weeks were eligible for inclusion. The primary outcome measure was re-consultation within 14 days for the same or a related problem. Secondary outcome measures were care processes as recorded in the record (diagnostic tests ordered, referrals made, prescriptions issued, general advice and medication management advice given), patients’ satisfaction, and length and cost of consultation.

These authors developed a tool for systematically estimating the clinical complexity, severity, and urgency of the presenting complaint and relevant sociodemographic factors (for example, age, deprivation), which is written up in a separate paper and explained on bmj.com (page 9).20 After adjusting for case mix by using this tool, the authors found that re-consultation rates were higher with physician associates (24.6% v 18.6%) but this difference was not statistically significant (although, partly because they used different time periods for the sample size calculation and data collection, the study was underpowered to detect a clinically significant difference in these rates). Cost data from this study are discussed in the following subsection.

Drennan and colleagues’ 2015 study was designed primarily to test whether physician associates generate additional workload for general practices as measured by re-consultation rates, and the answer in that study seems to be no.18 That conclusion should be interpreted in the light of the study’s significant limitations, most notably that no more than seven physician associates were studied; case mix differed significantly between the samples; and, because the design was not randomised, multiple unmeasured confounders cannot be excluded. The work was done in research practices in southern England in 2011-12, a time before the current workload crisis in general practice (hence, general practitioners’ capacity to supervise physician associates is likely to have been greater).444546 The study’s findings, which pertain only to same day appointments in general practice, have not been replicated.

De Lusignan and colleagues (2016) report a sub-study of 62 videoed consultations sampled from the above study (41 by five general practitioners and 21 by four physician associates).19 After editing out of sections that would have revealed the staff group of the clinician, the recordings were analysed by experienced general practitioners using a modified version of a structured assessment tool (the Leicester Assessment Package47). Using this tool, “all consultations were assessed as safe; but general practitioners were rated higher than PAs in all elements of consultation” (page 1).19 Although some consultations in both samples were inadequate, most consultations by physician associates were, according to the scoring system, “satisfactory” but tended to “lack discrimination, organisation and good time management”; and one in six consultations by physician associates (compared with approximately one in 16 by general practitioners) had “inadequacies” (see bmj.com, page 9-10, for further detail). These findings pertain to a tiny sample of only four physician associates and have not been replicated.

The only other (and more recent) published research study on the performance of physician associates in UK primary care was a mixed methods evaluation of the impact of expanded skill mix including multiple clinical roles.21 Although this was a large and rigorously conducted study, only three physician associates were included in the sample and findings from that group were limited. One general practice in this study had stopped deploying physician associates because they were seen as “needing a lot of support,” “highly protocol driven,” and “lacking in clinical experience,” as well as unable to prescribe or order imaging.21

Further details of studies in this section are given in table S3 and accompanying notes on bmj.com. The other categories below are less centrally relevant to the formal terms of reference of the Leng review, but we have included a brief summary of those topics because they are likely to have some bearing on policy.

Costs and cost effectiveness of physician associates

No published research studies on costs or cost effectiveness of physician associates met our inclusion standard; one on anaesthetic associates did.23 We found three studies on physician associates that attempted to ascertain costs,161718 and they all struggled. The Drennan 2019 study on hospital wards described above had planned a detailed economic evaluation (see their report to funder, page 19, for details22) but found that the costs and benefits of physician associates could not be disaggregated from those of the wider team.16 The lack of hard economic data was not because of methodological flaws but because it was a key finding of the study that physician associates’ work was inextricably interwoven with the work of other team members. The same team’s study of physician associates in emergency departments suffered from inaccessibility of key data; it, too, produced no economic estimates but for a different reason.17

In Drennan and colleagues’ 2015 study in primary care (involving a maximum of seven physician associates),18 the estimated cost per consultation for physician associates after adjustment for case mix (calculated by multiplying the average length of consultation by the average hourly rate of the clinician from national validated unit costs) was significantly lower than for general practitioners, even taking account of the longer consultation length (£28.06 v £34.80, a difference of 18%). However, whereas physician associates were encouraged to consult general practitioners in real time for advice, and they did so, this general practitioner time was not factored into the cost data (or even measured). Hence, this small study systematically overestimated the apparent cost effectiveness of physician associates and the degree to which general practitioners were “freed up.” As Nelson and colleagues comment (page e495), “If PAs saved some GP time, extra time was incurred supervising trainees, making overall net savings hard to gauge.”27

Drennan and colleagues (2015) could have done a sensitivity analysis to estimate the cost of supervision. Using their own figures, if each physician associate consultation took, on average, one minute of general practitioner time to supervise (including, for example, confirming a diagnosis and issuing a prescription, as well as checking the physician associate’s written records), the cost (including physician associate and general practitioner time) would rise to £31.14; this would be £34.20 for two minutes, £37.30 for three minutes, and so on. Other sections also raise the possibility of higher indirect costs with physician associates, such as investigations, prescriptions, and the unanticipated inefficiencies associated with expanding new staff roles in general practice.

In relation to cost effectiveness of anaesthetic associates, Hanmer and colleagues (2024) present an economic model comprising hypothetical scenarios of the relative costs of different supervisory models (for example, one doctor supervising two anaesthetic associates across two operating theatres). The paper, which argues that such supervisory arrangements would be cost saving only if anaesthetic associates were paid considerably less than they currently are, included real salary costs but no empirical data from actual deployments.23

Further details of studies in this section are given in table S4 and accompanying notes on bmj.com.

Patient and public attitudes to physician associates

Published research on the attitudes of patients and the public to physician associates was covered in eight papers, of which three met our inclusion standard.242526 In these, patient and public attitudes to physician associates varied but overtly negative attitudes were rare. Many study participants were unaware of the physician associate’s role, and some patients thought a doctor was seeing them. Patients were mostly happy being seen by physician associates provided they were working within their competence and adequately supervised (but not otherwise). In one well conducted study, trust in the physician associate seemed to be derived from trust that the NHS and the supervising doctor would not employ someone unsuitable.24 Patients wanted to be told that the person seeing them was a physician associate.

Further details of studies in this section are given in table S5 and accompanying notes on bmj.com.

Staff perceptions of physician associates and anaesthetic associates

Of 18 papers (reporting 17 studies) on the attitudes and experiences of other staff towards physician associates (14 studies) or anaesthetic associates (three studies), 10 met our inclusion standard. They comprised local qualitative or mixed methods studies (four in secondary care,16282930 and three in primary care252731) and three regional or national surveys.323334

Many local studies had been done before physician associates had been introduced widely at the study site. Where physician associates or anaesthetic associates were working in multidisciplinary teams in longstanding arrangements, staff on those teams generally spoke positively about them, describing them as “an extra pair of hands”30 and valuing the continuity they provided. However, this could reflect survivorship bias if other sites had started but then abandoned employment of physician associates. An exception to the broadly positive views was high risk or high dependency specialties (for example, intensive care, high risk patients in anaesthetics), where senior doctors thought that doctors in training were more appropriate than physician associates or anaesthetic associates for the work required.162830 Clinicians and managers recognised the need to tackle staff shortages and rising demand but expressed concern about how the physician associate role would be operationalised, especially in relation to their scope of practice, their level of competence (for example, physician associates’ ability to handle medical complexity and the associated risks to patients’ safety), the level of supervision needed, and the operational limitations of non-prescribers working as substitutes for doctors.252734 Managers questioned the relative value of physician associates compared with other staff groups.34

A 2019 online survey of all UK general practice managers (17% response rate) found that many were employing or seeking to employ physician associates in their practice in the context of a policy that provided ring fenced funding for employing physician associates (and some other occupations) but not doctors.33 However, only 14% thought they would do so if they paid for this staff group out of their own budget. A secondary analysis of data from the 7th National Audit of the Royal College of Anaesthetists (undertaken between 2020 and 2022; 10 009 responses) found that anaesthetic associates, who accounted for less than 1% of the anaesthetic workforce at the time, were mostly working under supervision with low risk cases; however, in a handful of instances, an anaesthetic associate was working alone, outside their locally agreed scope of practice, with higher risk patients.32

Further details of studies in this section are given in table S6 and accompanying notes on bmj.com.

Experiences, training, identity, and career paths of physician associates

Of the 20 papers in this category, only five (describing four in-depth qualitative studies)2930353637 met our inclusion standard; the remainder were mostly small, with evident biases, single site, or out of date. Physician associates seemed to have moderate job satisfaction but sometimes experienced other staff groups as being “negative” towards them.2930 In some settings, especially primary care, physician associates were unclear about their scope of practice, under-confident in performing the role expected of them, troubled by the amount they were expected to know, and stressed from having to explain their role to other staff continually.30 Researchers suggested the need for staff to be educated about the physician associate role and for local physician associate “champions” (for example, senior doctors who backed the role) and appropriate role models (that is, other physician associates).293536 Career paths of physician associates seemed to be uncertain and characterised mostly by lateral moves (to another equivalent job) rather than vertical ones (to a more senior role).37

Further details of studies in this section are given in table S7 and accompanying notes on bmj.com.

Policy, organisation, and systems research on physician associates

This category included 11 papers (of which seven met our inclusion standard), including two from Drennan’s team3138 and six from Spooner’s team.2139404849. Drennan and colleagues’ studies3138 showed that a strong push exists for new staff roles from national policy makers in England, driven by concerns about workforce planning, although a weakness of their analysis is the conflation of multiple different roles into a single category of “non-medical practitioners” (which includes existing clinical professions such as nurses and pharmacists, as well as a range of health occupations).38 Drennan and colleagues also documented a conviction among some national policy makers that physician associates have already been shown to be effective, clinically safe, and able to “free up” other clinicians, but the same study also found evidence of resistance from professional bodies, which were less convinced than national policy makers of the value and safety of physician associates and their place in relation to other professional groups.31

The more recent body of work by Spooner and colleagues has shown that the introduction of physician associates in English general practice has occurred as part of a wider expansion of staff roles and has led to challenges in managing this skill mix (for example, how to allocate patients to the most appropriate staff member).2149 Large quantitative studies in English general practice by this team suggest that introducing a wider mix of staff, far from being associated with improved efficiency of care or better patient satisfaction, seems to be associated with the opposite.394048

An international comparative study of physician associates’ scope of practice across 25 countries confirmed that this title is associated with very different roles and levels of skill in different countries; this important study illustrates that people with the title “physician associate” cannot simply be imported from any country and deployed in UK.41 A national level study of workforce policy in England from the Nuffield Trust (based on interviews and small surveys of staff groups and published in January 2025) found that physician associates are increasingly deployed in the NHS and that much debate and controversy exist about their roles and impact.4 This recent study affirmed many of the findings of our review, including that public awareness of the physician associate role remains low, with patients often mistaking physician associates for doctors; that staff have mixed views and concerns about safety and would like a more precise scope of practice for physician associates; and that the anticipated cost savings have proved elusive because of the hidden costs of supervision and knock-on inefficiencies across the system.

We identified no papers describing policy, organisation, or systems research from the other UK jurisdictions. Further details of studies in this section are given in table S8 and accompanying notes on bmj.com.

Patient and public comments

The two lay people who read this review thought that it reflected patients’ priorities and concerns. However, they pointed out that patients’ views on physician associates obtained in the research reported here would not have captured the more recent public concern that has emerged after adverse coverage of some physician associate related incidents in the press. These commentators underscored patients’ desire to know that the person seeing them is not a doctor and for physician associates and anaesthetic associates to work within an appropriate scope of practice. Their comments are reproduced in full on bmj.com (see page 32 of supplementary material), along with comments from two physician associates.