Ultrasound skills teaching in UK medical education: A systematic review

Sonography is increasingly integrated into medical curricula to prepare students for clinical practice. In 2022, we conducted a systematic review to explore the degree to which ultrasound skill acquisition is incorporated into undergraduate medial education in the United Kingdom.

In 2003, it was noted in 'Tomorrow's Doctors', which provides guidance for UK medical schools, that 'clinical and basic sciences should be taught in an integrated way throughout the curriculum' 2 ; the inclusion of ultrasound skills training in the undergraduate curriculum could be considered an embodiment of this.In the United States, where ultrasound is more widely integrated, Hoppmann et al. 3 proposed an ultrasound curriculum as early as 2006.Recommendations for wider ultrasound integration in medical education in Europe have also been put forth by the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB). 4Regardless, ultrasound teaching is yet to be widely incorporated into the UK undergraduate medical curriculum, and the skill of using ultrasound is not mentioned in 'Outcomes for graduates: Practical skills and procedures'. 5 2014, the School of Medicine at Leeds University was the first in the United Kingdom to formally incorporate ultrasound teaching into all years of its curriculum, into anatomy and clinical modules. 6ere is ongoing debate over regarding the stage that ultrasound skills teaching should be integrated into the medical curriculum, with some medical schools opting for pre-clinical integration during anatomy lessons and others favouring a more clinical approach in hospitals. 7,8trasound has the advantage of being a safe, non-invasive, portable imaging modality, which can give real-time visuals and is cheaper than most other medical imaging modalities.These qualities help facilitate the integration of ultrasound into teaching sessions.The absence of a UK ultrasound curriculum may stem from a lack of evidence for the potential benefits.A 2018 scoping review concluded that it was 'feasible and beneficial to medical students'. 9However, a 2017 systematic review concluded that 'the literature demonstrates mostly absent or mixed evidence in support of rationales for the integration of ultrasound teaching in undergraduate medical education'. 10Regardless of the ambiguity surrounding the need for ultrasound teaching, it is nevertheless a useful exercise to evaluate the growth of such teaching in a UK context.
The aim of this review was to describe how ultrasound skills teaching is being integrated into the medical programmes of UK medical schools, since a centralised ultrasound curriculum is currently lacking.We explored teaching methods, specific skills taught, equipment used and instructor skill levels.We also examined the outcomes of these programmes in terms of student satisfaction and any reported quantitative analysis of programme efficacy.

| Data extraction
Information from the 15 articles included in the qualitative synthesis was recorded in a pre-piloted standardised data extraction spreadsheet.Data headings in the spreadsheet included 'teaching approach', 'participant cohort', 'ultrasound machine to participant ratio', 'precautions in place for incidental pathology', 'year of study of participants', 'type of ultrasound machine', 'instructor occupation', 'simulated patient information' and 'study outcome measures'.A narrative approach was taken towards data analysis to build a picture of how ultrasound is being used in UK undergraduate education.

| FINDINGS
A flow diagram of our study selection process is outlined in Figure 1.
In total, 2,599 studies were considered, and after screening, we identified 15 eligible studies as summarised in Table 1.The year of publication ranged from 2008 to 2022 despite a search limit of 2003-2022.
Six of the 15 studies included more than 100 participants, while two studies did not mention a specific number of participants. 6,7The median number of participants per study was 47.5.A total of eight UK medical schools provided evidence of ultrasound teaching to undergraduate students, although two institutions remained anonymous. 7l studies originated in England with the exception of one Northern Irish study. 12Participants represented students from all years of undergraduate study, although the majority of studies used participants in their clinical years (year 3-5).Some studies included additional groups such as students undertaking a MSc in Vascular ultrasound 13 and junior doctors. 8The teaching intervention was typically integrated into standard academic courses or designated hospital assignments, with recruitment typically being voluntary.The numbers of participants per teaching group varied, with fewer students in the groups receiving hands-on experience versus those that received demonstrations.

| Teaching methods
Table 2 details the teaching approaches described in the included studies.Twelve studies facilitated hands-on student experience of ultrasound, and only two relied solely on didactic demonstrations. 14,15st studies focused on normal anatomy; however, five studies incorporated pathological features. 6,12,13,16,17One study compared a group of students receiving an ultrasound anatomy demonstration with a control group taught via traditional cadaveric anatomy and found that both groups performed comparably well on a post-intervention assessment. 15A B L E 2 Overview of teaching approaches and ultrasound skills.

Study
Teaching approach Specific ultrasound skills taught Allsop et al. 14 Pre-course reading.Live ultrasound demonstration.

Gastrointestinal anatomy
Armson et al. 20 Pre-course reading.Staggered rotation of hands-on practical stations.

Peripheral intravenous catheter insertion
Dickerson et al. 16 3 peer-taught stations, with hands-on ultrasound experience.AAA screening, FAST scanning Gogalniceanu et al. 17 Case-based discussions, problem-solving exercises, and a hands-on FAST scan of a volunteer.Seminars and practical demonstrations.
FAST scanning course, Free fluid detection Griffiths et al. 18 Training, followed by ultrasound practical.Both cross-sectional and longitudinal hands-on approaches.
Aspiration of blood from a deep vein Griksaitis et al. 15 A pre-intervention MCQ.Participants then allocated to cadaver group or a group that received a ultrasound practical demonstration.
Heart, Great vessels Jaffer et al. 13 Instructional video and hands-on practical.Game task to assess the waveform type and measure the peak systolic velocity.
Vascular US, Lower limb arterial anatomy, clinically relevant arterial pathology Okereke et al. 23 Training, demonstration, and hands-on practice.

| Equipment used
The reviewed medical schools took a variety of approaches to sourcing and selecting ultrasound machines (Table 3).The machines used varied in price between approximately £4,600 and £69,000.Cartbased machines were generally more expensive than the portable machines.Four studies used cart-based machines only, 8,14,18,19 six studies used portable machines only 7,12,15,[20][21][22] and three studies used a combination of both 13,16,17 (Table 3).Of the portable machines, three studies used handheld pocket ultrasound machines, which further reduced the cost. 16,17,20

| Teaching delivery
Regarding the ultrasound session facilitator, 11 studies used clinicians, 6,8,13-15,17,19-23 4 included academic staff 6,7,14,20 and 1 included near-peer facilitators (Table 1). 16Patten 7 compared a group taught by anatomy demonstrators alone against a group taught by anatomy demonstrators in combination with sonographers.Students taught by the latter group reported greater understanding of anatomy, and the former group had greater reported heterogeneity in tutor expertise.

| Outcome evaluation
The evaluation outcomes for each study are summarised in Table 4.
Methods employed to evaluate the ultrasound intervention included student perception surveys, multiple-choice question (MCQ) assessments, practical examinations or a combination thereof.One study included a viva voce assessment. 19Three studies conducted a longitudinal, multi-year analysis. 6,7,22Only three studies included a preintervention questionnaire for comparison with post-intervention measures. 15,20,23ree studies focused on needle insertion rather than basic anatomical concepts, 18,21,23  Medical schools need to consider the formal introduction of ultrasound teaching in their curricula to equip future doctors with relevant skill sets.
Griffiths et al. 18 Practical assessment, Visual analogue scale.
When cross-sectional and longitudinal approaches were compared, the mean number of attempts to aspirate fluid was 1.13 and 1.30 respectively and the mean time to aspirate was 45.1 s and 52.1 s respectively.
The mean difficulty out of 10 was 3.97 for the crosssectional approach and 3.93 for the longitudinal approach.
There was no significant difference in effectiveness between the crosssectional and longitudinal approaches to ultrasoundguided venepuncture.
Griksaitis et al. 15 Pre & post intervention practical assessment The mean score improved by 31.63% after the ultrasound teaching to 85% for both groups.
There was no significant difference between the a There was no statistical difference in ultrasound teaching and cadaver.
T A B L E 4 (Continued) pre-test & postintervention scores of the cadaver and ultrasound teaching groups.
Jaffer et al. 13 Continuous assessment using the DUOSATS for simulation and cumulative imaging score, Likert scale anchored at 4 points.
Novices improved DUOSATS from 18 on day 1 to 30 on day 4. On the final, there were no significant differences between novices and MSc students in DUOSATS.Novices were better at identifying and assessing pathology compared with MSc students.
Most students found the scanning to be beneficial, enjoyed working in pairs and would recommend the course.Although they were not as confident performing the F-VLAD scan and scanning real patients.
Students were able to achieve a mean of ≥80% success in the post-intervention assessment.
Student perceptions on ultrasound teaching were positive overall.
In two studies, students described ultrasound teaching as being too short and would have preferred longer or more frequent sessions. 7,13 addition, Patten 7 also presented the perceptions of the tutors, who highlighted that students were motivated by the clinical contextualisation.However, the tutors also noted that some students did not enjoy ultrasound teaching and found image interpretation very difficult.
Students were motivated by the clinical contextualisation.practice sessions. 19The use of open practice sessions is also supported by others 24 and may address issues related to restricted curricular time.However, caution must be raised over the potential for the development of bad technique or confusion due to a lack of tutor guidance.
Open practice sessions may address issues related to restricted curricular time.
Two studies refer to the use of case-based learning as a means of teaching ultrasound. 8,17This style of learning has grown in popularity over recent years, with several UK universities adopting a case-based approach to pre-clinical teaching.A case-based approach where ultrasound images are contextualised with patient data and radiology reports would help merge the basic science of ultrasound imaging with its clinical applications.
The incorporation of ultrasound into a curriculum does pose some obstacles: Operator experience is necessary, devices are costly, volunteers are required and there is always the risk of discovering an undiagnosed pathology. 15According to a survey conducted in the United States, 94% of schools further highlighted obstacles to integrating POCUS in undergraduate medical education, including a shortage of educated faculty (63%), time in the curricula (54%) and shortage of ultrasound machines (44%). 25

| Operator experience
Patten 7 surveyed sonographers in two UK medical schools who reported they were worried that non-sonographers instructing medical students would not employ proper scanning methodology or be unable to decipher sonograms.This viewpoint may act as a roadblock to the creation of ultrasound courses and may account for the challenges some tutors encountered while attempting to connect with local sonographers.Patten 7 suggested that training of demonstrators by a sonographer was deemed to be sufficient if the scope of the ultrasound teaching session is limited.This concords with Hoppmann et al., 26 who suggest only basic ultrasound skills need be addressed in the undergraduate medical curriculum and more advanced skills should be reserved for elective opportunities or student interest groups.
Nearly half of surveyed US medical schools rely on peer-assisted learning (PAL) to deliver POCUS instruction. 25The only UK study to mirror this approach was Dickerson et al. 16 ; their findings concluded that PAL was an acceptable method of teaching ultrasound.Cognitive congruence between peer and student may enable effective teaching, but one randomised controlled trial suggested prejudice from students may affect subjective evaluations of peer tutors. 27gnitive congruence between peer and student may enable effective teaching.

| Ultrasound machines
One of the main obstacles in establishing a university ultrasound programme is the need for specific equipment and resources.The majority of included studies involve short-term teaching programmes with borrowed equipment and volunteer ultrasound experts.Indeed, a long-term teaching programme may require the purchase and maintenance of expensive equipment.Regarding the ultrasound machines used in the selected studies, portable machines were generally less expensive than cart-based machines.However, Gogalniceanu et al. 17 demonstrated a clear preference for larger cart-based ultrasound machines, with 96% of students favouring cart-based machines over portable machines.This was due to better image quality and ease of interface use.Although it should be considered that this study is a decade old and the image quality of portable ultrasound equipment is continually improving.Costs can be reduced by renting, using existing machines at times when they are not in use or forming a partnership with ultrasound manufacturers.A potential alternative not mentioned in the UK literature is virtual ultrasound simulation, which could provide a cheaper option for schools with less resources.Indeed, the use of low-cost simulators with peer-teaching was suggested by Birrane et al. 9 However, simulators may not yet be on par with the physical machine in teaching students how to operate ultrasound equipment in clinical settings.

| Strategy for incidental pathology in volunteer scans
Only three studies in our review pre-scanned healthy volunteers to screen for potential tumours or other pathologies prior to their imaging in a classroom setting. 13,14,22Griksaitis et al. 15 identified 12 tips for incorporating ultrasound into medical education.They believed the university must have a 'situations requiring further investigation' strategy in place to deal with scenarios of incidental pathological findings.15]22 The consequence of not pre-scanning may include inadvertently presenting pathological anatomy, pregnancy or simply a subject that is difficult to scan.For example, sarcopenia in an elderly patient was reported in one study, which complicated ultrasound assessment of the knee. 6Pre-scanning may help to ensure a consistent learning environment for all students.A review by Patel et al. 28 also underlined the importance of having appropriate strategies to follow in the case of inadvertent pathology and clear consent procedures in place for any student volunteers.
Pre-scanning may help to ensure a consistent learning environment for all students.
Although most studies used volunteer patients, in a few studies, manikins were used, which would avoid the issue of incidental pathology. 18,20,23However, the use of manikins can be expensive and frequently does not result in dynamic, lifelike visuals.

| Developing clinical skills
The integration of ultrasound into the clinical years of training appears to be more common than integration into pre-clinical education.A variety of different modalities and techniques were found to be employed in UK medical schools, such as image-guided interventional procedures (peripheral venepuncture, cannulation and arterial blood gas sampling).It is unclear whether the small amount of ultrasoundguiding training received by students would translate to significant effects on skilfulness.Blehar et al. 29 concluded that to achieve proficiency, a large number of procedures, often exceeding 50, must be performed.This underlines the challenge in providing medical students with effective ultrasound training.
FAST was taught in two studies. 16,17Gogalniceanu et al. 17 concluded that the reduced learning curve of performing FAST scans makes it a realistic teaching goal.Two studies focused on echocardiography.that echocardiography could be incorporated into an already densely packed undergraduate medical programme. 12,13,17,22Liu et al. 30 illustrated that a POCUS programme led to a significant increase in OSCE scores, including in stations where ultrasound was not specifically assessed.This suggests that ultrasound education may in fact improve a student's overall understanding of the physical exam.

| Student perceptions
Student perception was largely supportive of ultrasound teaching, with many stating that ultrasound should be integrated into medical curricula, 16,17 while others highlighted that ultrasound teaching should last longer or occur more frequently. 7,13However, this may be due to the fact that students were required to actively volunteer to take part in these studies and may have had a pre-existing interest in ultrasound imaging.Hoppmann et al. 3 demonstrated that 93% of first-and second-year medical students thought that an integrated ultrasound curriculum enhanced their overall medical education.The response rate was greater than 90%, and since entire year groups were receiving ultrasound teaching, as opposed to self-selecting students, this would support the main finding in this review; that is, medical students are in favour of ultrasound integration.Although ultrasound is often positively received by students, this may not always translate into educational significance.Feilchenfeld et al. 10 cautioned that there is seldom evidence of harm or flaws until after curricular changes have been implemented and decisions are sometimes based on a tiny amount of evidence.

| A defined curriculum
The Society of Ultrasound in Medical Education (SUSME) and the World Interactive Network Focused on Critical Ultrasound (WINFOCUS) recently produced joint consensus recommendations for a global ultrasound curriculum for undergraduate medical education. 26The panel consisting of 64 experts recommended integration of hands-on ultrasound practice into basic and clinical sciences to compliment the curriculum, enhancing understanding of anatomical, physiological and pathophysiological processes.The recommendations also addressed concerns that students could become overconfident in their capacity to detect or exclude pathology using ultrasound.In our review, two papers focused on abdominal aortic aneurysms, 16,19 which is one of the pathologies that was advised against being included by the experts.This exemplifies the advantage of an evidence-led standardised curriculum.

| CONCLUSION
Ultrasound teaching is not widely incorporated into UK undergraduate medical curricula as of 2022.A variety of different ultrasound techniques and modalities are currently being taught with unclear potential benefits.Existing consensus statements could be used to guide a curriculum appropriate to UK medical schools and to determine which skills are most beneficial and cost-effective.This review has highlighted that non-invasive ultrasound procedures including FAST scanning and echocardiography are realistic teaching goals for undergraduate medical schools and a short period of ultrasound training can enable students to pass US-themed clinical examinations to a professional standard. 12,13,17,19Furthermore, integrating ultrasound skills teaching into anatomy modules is popular amongst students and helps link the basic sciences with their clinical applications.This review has highlighted approaches, obstacles and their solutions to the incorporation of ultrasound related teaching in a medical curriculum.However, a clearer view of the benefits of ultrasound teaching may be required to motivate the establishment of a UK-wide ultrasound curriculum.
This review has highlighted that non-invasive ultrasound procedures including FAST scanning and echocardiography are realistic teaching goals.

2 | METHODS 2 . 1 |
Search strategy and study selectionA systematic literature search was conducted on 30 June 2022 of Medline and Embase databases, in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. 11Search limits were applied to only include articles published in English since 2003.The rationale for this is the 2003 publication of 'Tomorrow's Doctors', which detailed guidance on the increased incorporation of clinical skills into undergraduate medical education. 2Studies were included if they were primary research articles detailing the use of ultrasound in the teaching of UK undergraduate medical students.The following Medline search strategy was used: (ultrasound OR ultrasonography OR insonation OR POCUS) AND (education, medical/ OR education, medical, continuing/ OR education, medical, undergraduate/ OR teaching rounds/ OR medical curriculum OR undergraduate medicine OR students, medical/ OR medical teaching).The following search strategy was used for Embase: (ultrasound OR ultrasonography OR insonation OR POCUS OR point of care ultrasound) AND (Medical school/OR undergraduate medicine OR medical curriculum OR medical student OR medical teaching).No ethical approval was required for this study as it was a review of published literature.Records were exported into EndNote X9 (Clarivate), and duplicates were removed.Title and abstract screening was carried out by two independent investigators (EMcC and BF).Articles were excluded if they involved a non-UK population or a postgraduate medicine course, were not in the English language or took the form of an abstract, letter, review or editorial.Only primary research studies were included.Reference lists of included studies were screened for any additional relevant articles.Any discrepancies were resolved by discussion with a third reviewer.F I G U R E 1 Flow diagram summary of systematic review process.T A B L E 1 Summary of the included studies.
Abbreviations: A, academic staff; C, clinician; D, anatomy demonstrators; P, student peers; MS-A, medical school A; MS-B, medical school B; RCT, randomised controlled trial; S, sonographer; T, tutors trained in musculoskeletal ultrasound; V, vascular lab manager.

21 4. 1 |
remaining two studies compared methods of needle insertion and the adverse effect of mental factors including anxiety on ultrasound proficiency.18,Teachingmethods Most of the included studies allowed opportunities for hands-on ultrasound experience.This accords with the recommendations made by Hoppmann et al.,3 who eliminated didactic ultrasound lectures after a 9-year experience at the University of South Carolina.The university opted for a more self-paced and individualised style of learning by replacing didactic teaching with online modules, videos and open laboratory resources for self-practice.Indeed, one study in our review did merge bedside teaching with student-directed learning and free Outcomes of ultrasound interventions using both student performance and student perception.
with one of these describing a correlation of visuospatial ability (measured via a mental rotation test) and T A B L E 3 Technical aspects of ultrasound machines.a Data not provided.T A B L E 4