The head and neck models were created using ZBrush (Pixologic, California, USA). This digital sculpting software was used to recreate human anatomy by sculpting basic shapes. The individual anatomical components were then assembled and further edited on Netfabb (Autodesk, California) for manufacturing (figure 1A,B). The peritonsillar abscess was developed as a variation of the model created using the method above. Files were sculpted to include a peritonsillar abscess on Blender (Blender Foundation, Netherlands) and then printed in place of regular tonsils (figure 1B). The otology aspect was created using a combination of the above two methods (figure 1C). Ear CT scans were segmented using Mimics (Materialise NV, Belgium). Files that were not clear in scans were digitally sculpted in ZBrush and fitted into the model. Models were printed using the Stratasys Digital Anatomical Printer (Stratasys, Minnesota, USA). A combination of preset and custom digital materials was used to construct the model’s various components. The models can be seen in figure 2A–C, as well as in online supplemental appendix 1A, with endoscopic appearances shown in online supplemental appendix 1B.

The models were subsequently validated in an ENT emergencies training course using a prospective validation study. Delegates attended an in-person course on managing 10 common ENT emergencies. The 10 ENT emergencies included foreign body nose removal, epistaxis management, peritonsillar abscess drainage, flexible nasendoscopy for stridor assessment, post-tonsillectomy bleed management, foreign body removal from the throat, Pope otowick insertion/otitis externa management, foreign body removal from the ear, tracheostomy insertion and drainage of a post-thyroidectomy haematoma.

This was a 1-day course consisting of small group lectures and practical skills sessions using 3D printed head and neck models. The faculty consisted of ENT consultants/attending surgeons, with a faculty-to-delegate ratio of 1:5 to aid in procedural steps and teaching. 3D model simulation training was delivered after delegates had received tutorials on common ENT emergencies and their management. Delegates rotated through 10 simulated stations, each starting with a case study of a common emergency presentation related to the skill being practised. They then spent 30 min using the models to practice each emergency procedure under the guidance of ENT consultant surgeons, rotating through each emergency. The equipment provided for each skill mirrored what is typically available in an emergency department, including headlights, tongue depressors, scalpels, syringes, needles, ribbon gauze and cautery sticks. Additional specialised equipment included microscopes for the otitis externa management, Pope otowick and foreign body ear stations, as well as flexible nasendoscopy for stridor assessment. Following the completion of the course, delegates were asked to complete paper surveys, which adopted a combination of yes/no items and Likert scales to evaluate their experience with the 3D models. All delegates provided informed consent to have their data used as part of a research study for the validation of the 3D models.

The validation of the 3D models involved a combination of methods. First, face validity was assessed by having delegates evaluate the realism of the models for performing ENT emergency procedures. Second, content validity was ensured through mapping the ENT procedures included to the postgraduate primary care and EM curricula.11 12 Moreover, content validity was further assessed by having ENT consultants rate the realism of the models specifically for performing common ENT emergency procedures. Lastly, indirect criterion validity was determined by assessing self-reported confidence of delegates in performing ENT emergency procedures after using the 3D models.

Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

A total of 90 delegates and 11 ENT consultant/attending surgeons used the 3D printed models for ENT emergency skills training and responded to the survey. Among them, 60% (n=54) were EM residents/trainees, 28% (n=25) were primary care residents/trainees, 4% (n=4) were ENT residents/trainees, 4% (n=4) were emergency nurse practitioners, 2% (n=2) was a primary care attending physician and 1% (n=1) was an EM attending/consultant. Prior experience in common ENT emergencies was assessed for 90 of the delegates (excluding ENT consultant/attending surgeons), which is displayed in online supplemental appendix 3.

Delegates (n=90) were asked about their current teaching on ENT Emergency procedures they receive within their department. No teaching was received by 58% (n=52) of delegates, while 26% (n=23) received lecture-based teaching, 12% (n=11) received small-group teaching and 4% (n=4) received teaching on real patients. None of the delegates had used 3D models within their local department teaching.

Face validity was assessed by asking delegates to rate the realism of the models, as displayed in table 1. Results indicated good face validity, with 70%–98% (range: 35–49) of delegates rating the realism as very good/excellent.

The overall realism of the model, including its visual appearance, internal/external anatomy and simulation of procedures, was reported using a 5-point scale: excellent, above average, average, below average or poor. Delegates rated the models as ‘excellent’ or ‘very good’ for performing the 10 emergency procedures: flexible nasendoscopy to assess for stridor (n=77, 86%), assessing and removing nasal foreign bodies (n=77, 86%), assessing and removing foreign bodies from the ear (n=81, 90%), managing otitis externa with Pope otowick insertion (n=83, 92%), assessment and management of a peritonsillar abscess using needle aspiration (n=68, 76%), assessing for and removing a foreign body from the throat (n=74, 82%), performing a tracheostomy (n=63, 70%), managing a post-thyroidectomy haematoma (n=72, 80%), managing epistaxis using cautery and nasal packing (n=68, 76%) and managing a post-tonsillectomy bleed (n=77, 86%). The full results depicting the delegate-reported realism of the models can be seen in table 1.

Delegates were asked to rate the realism (5-point scale: excellent, above average, average, below average or poor) of the haptic/tactile feedback provided by the models compared with real patient tissue. This encompassed the perception of pressure, vibration and resistance when performing the procedures and comparing these to what one might expect in a real patient. Most delegates rated this as excellent or very good (n=58, 64%), followed by 32% (n=29) rating them as average, and 4% (n=4) rating them as below average.

Furthermore, delegates and ENT consultants were asked to rate the realism (5-point scale: excellent, above average, average, below average or poor) of the tissue texture and handling compared with real patient tissue, which added to the content validity. This encompassed the firmness, elasticity and texture accuracy as compared with real tissue. Most delegates rated this as excellent or very good (n=67, 74%), with 24% (n=22) rating them as average and 1% (n=1) rating them as below average.

Content validity was ensured by mapping the procedures to the primary care and EM postgraduate curricula.11 12 This assurance was further fortified by incorporating 10 common ENT emergency procedures. This was following discussions with ENT surgeons across the UK. This step ensured the relevance of the models and skills to those working in EM and primary care. Moreover, having consultant ENT surgeons rate the realism of using the models in simulating 10 common ENT procedures furthered the content validity. The full results depicting ENT consultant reported realism of the models can be seen in table 2. Similar results between the ENT consultant surgeons and delegates were seen regarding the realism, which highlights good content validity.

ENT consultants were asked to rate the realism (5-point scale: excellent, above average, average, below average or poor) of the haptic/tactile feedback provided by the models compared with real patient tissue. All (n=11, 100%) ENT consultants rated the models to be excellent or very good for haptic/tactile feedback compared with real patient tissue.

Furthermore, ENT consultants were asked to rate the realism (5-point scale: excellent, above average, average, below average or poor) of the tissue texture and handling compared with real patient tissue. All (n=11, 100%) of the ENT consultants rated the tissue handling in comparison to real patient tissue as excellent/very good.

Next, we analysed the indirect criterion validity by assessing delegates’ self-reported confidence after using the 3D models. The confidence levels of delegates in practising common ENT emergencies are displayed in table 3 with most delegates (74%–96%) feeling confident in performing the 10 ENT emergency procedures following the use of the 3D models. Hence, demonstrating good indirect criterion validity.

Overall, 56% (n=28) of delegates found the models to be extremely helpful in enhancing their learning of ENT emergencies, with 30% (n=15) finding the models very helpful and 14% (n=7) finding the models moderately helpful to their learning. No respondents found the models slightly or not at all helpful.

Overall, 90% (n=81) of delegates would recommend the use of 3D models to other trainees for learning ENT emergency procedural skills, similarly 100% (n=11) of ENT surgeons would recommend the use of 3D models to their trainees. Additionally, 80% (n=72) of respondents stated that they would prefer to have 3D models in future courses as their preferred method to practice ENT emergency skills, while 20% (n=18) of respondents would prefer to see a combination of 3D models together with cadavers.

Overall, for the delegates and ENT surgeons, 98% (n=99) of respondents felt that implementing the 3D models into local ED/primary care settings would help improve trainee confidence in ENT emergency procedural skills, while only 2% (n=2) were unsure about this. Delegates were asked, “What would be the biggest factor in deciding whether to incorporate 3D models into your local department for learning ENT emergency skills?” In response, 62% (n=56) cited the availability of local faculty to assist in teaching, 31% (n=28) stated that cost/price of models would be a determining factor and 7% (n=6) mentioned that the longevity of the model would influence their decision.

Within our cohort, the 3D models were associated with increasing self-reported confidence by the delegates performing 10 common ENT emergency procedures. Given the specialised nature and often time-critical state of ENT emergencies, frontline staff, such as EM doctors and primary care physicians, should undergo training to develop confidence in performing common ENT emergency procedures.3 5 7 A doctor’s competency in procedural skills is paramount to patient safety, as evidenced by the increased mortality, morbidity and prolonged hospital stays associated with procedure-related complications.13 A previous study highlights that junior doctors working in ED are not confident in identifying and managing common ENT emergencies.14 Delayed treatment for these conditions can lead to significant patient safety concerns and potentially death. With many ENT departments having an out-of-hours service where first-line emergency cover is provided by a cross-over system shared by other specialties, the on-call doctor may have no previous ENT experience.3 14 Hence, there is a clear indication for front-line providers working in the ED and primary care to receive training in performing ENT emergency procedures, with 3D models offering a method to facilitate this training.

Adopting novel 3D head and neck models has been demonstrated to enhance confidence in performing common ENT emergency procedures following a 1-day course. These models were associated with good face, content and indirect criterion validity.

Overall, 98.4% of our respondents felt that the models should be used in local ED/primary care settings to improve trainee confidence in ENT emergency procedures, with the models being adaptable to simulate various ENT pathologies. The availability of locally skilled faculty to allow for training was the biggest deterring factor for incorporating the models into local departments. The availability of experienced faculty to oversee and facilitate procedural skills allows for immediate feedback, reflection and learning. This, in turn, enhances simulated skills learning.15 16 However, the presence of experienced faculty may not be always required. Previous research suggests that independent use of simulators in surgery and procedural skills, without expert feedback, may be advantageous and preferable to proctored simulation.17 The models do allow for repetitive practice and training among trainees, which can in turn speed up skill adoption.18

The 3D models have the added advantage for gaining experience in certain procedures, where the clinical caseload and exposure may be low. Having locally available 3D models would allow doctors to practise emergency ENT procedures regularly and, therefore, prevent skill-fade.

Future research should compare the 3D model to existing training tools, such as cadaveric or animal models, where applicable. However, this may be challenging, as no single comparator method currently exists for all 10 ENT emergencies. Cadaveric and animal models cannot accurately replicate certain pathological states, such as quinsy or otitis externa. While procedures like tracheostomy can be compared across 3D, cadaveric and animal models, these traditional methods are often associated with high costs and regulatory constraints. Future studies should incorporate objective skills assessments to evaluate precourse and postcourse performance improvements using 3D models. Additionally, including participants with varying levels of experience in ENT emergencies would help distinguish differences between novice and expert groups.

This study had several limitations. First, each respondent had varied experience in ENT, which was not measured as part of the validation of the models. Second, ENT emergency procedure performance via an assessment of competence was not evaluated within this study; therefore, direct criterion validity was not measured. Third, the models were used in a non-validated training programme, and objective skill assessment scores were not measured precourse and postcourse. This could be an area for future research. Hence, the purpose was not to ensure that delegates were signed off and competent to deliver emergency care; rather, these 3D models were part of a course and are still in the evaluation stage. Finally, ENT experience/exposure was not measured beyond prior experience in performing the 10 procedures.

Not applicable.

Delegates taking part in the survey provided informed consent to participate in the study and have their data used as part of research by voluntarily completing the survey. All data collected was anonymous, and no patient data were collected or used as part of the qualitative research. In accordance with the ethical guidelines prevailing in the UK, an extensive ethical assessment was conducted using the UK Research and Innovation (UKRI) Research Ethics Tool prior to the initiation of our study. Ethical approval was not required as per the UKRI Research Ethics Tool (online supplemental appendix 2). Participants gave informed consent to participate in the study before taking part.