Developing A Diagnostic Decision Support System (DDSS) to Reduce Time To Diagnosis in Paediatric Shoulder Instability

Background: Currently the diagnosis of shoulder instability, particularly in children, is di�cult and can take time. These diagnostic delays can lead to poorer outcome and long-term complications. A Diagnostic Decision Support System (DDSS) has the potential to reduce time to diagnosis improve outcomes for patients. The aim of this study was to develop a concept map for a future DDSS in shoulder instability. Methods: A modi�ed nominal focus group technique, involving three clinical vignettes was used to elicit information physiotherapists decision-making processes. Results: Twenty-ve physiotherapists, (18F:7M) from four separate clinical sites participated. The themes identi�ed related to ‘Variability in diagnostic processes and lack of standardised practice’ and ‘Knowledge and attitudes towards novel technologies for facilitating assessment and clinical decision making’. Conclusion: No common structured approach towards assessment and diagnosis was identi�ed. Lack of knowledge, perceived usefulness, access and cost were identi�ed as barriers to adoption of new technology. Based on the information elicited a conceptual design of a future DDSS has been proposed. Work to develop a systematic approach to assessment, classi�cation and diagnosis is now proposed.


Background
Shoulder instability is an umbrella term used to describe complete or partial dislocation of the shoulder joint (1).Shoulder instability can affect children between eight and 18 years but this occurs most frequently in children aged between 14 to 16 years (incidence of 164.4 /100,000 person years), (2).Time to a con rmed diagnosis is normally two years and children can have up to 11 episodes of instability before formal diagnosis (3).Between 70% to 90% of children have repeated dislocations and have an increased risk of early onset of shoulder arthritis (1,3).Shoulder instability is associated with pain, decreased movement and limited function.A plausible reason for the poor prognosis is inaccurate diagnosis which may result in inappropriate treatment selection which occurs despite the availability of multiple classi cation systems (4-10), diagnostic/assessment guidelines (11,12) and management/treatment pathways (10,13) There is a need to improve diagnostic accuracy and prevent the development of long-term complications for this patient group (1,2).
Healthcare services are increasingly drawing upon technological solutions to improve diagnostic accuracy and e ciency, particularly within the context of the COVID-19 pandemic and subsequent 'Rebuilding of the NHS' strategy (14).One method of achieving improved diagnostic accuracy with technology is through using clinical or diagnostic decision support systems (CDSS/DDSS).The purpose of a DDSS is to provide clinicians with intelligently ltered information, speci c to the patient, which may facilitate decision making, such as clinical guidelines, alerts, or diagnostic support through suggestions of differential diagnosis or narrowing of etiologic causes (15,16).Although, DDSS is becoming increasingly common in the management of musculoskeletal conditions (17), existing systems are unable to support the diagnosis of shoulder instability (18).
A useful and robust DDSS should draw upon existing state of the art clinical decision making processes which subsequently inform treatment allocation.Successful implementation and adoption into clinical practice requires that the DDSS is developed in partnership with the end user group through early stakeholder involvement (19).
The aim of this study was to elicit the types of information used to make clinical decisions, with the longterm goal of designing and developing appropriate decision support technologies for the assessment and management of children with shoulder instability.

Methods
Ethical approval was gained from University Research Ethics Committee Review (NS-190032).
Participants from across four separate clinical sites were recruited within their capacity as health care professionals (physiotherapists), who have specialist interest in paediatric shoulder instability.A modi ed nominal focus group technique (20) comprised of the following stages was used: The methodology was explained to participants who were then introduced to a series of three clinical vignettes [1] (table 1) Participants were required to individually generate ideas in response to the seed questions that accompanied each vignette and this was recorded in a ip chart (NB: The order of participants was randomised to ensure that the most experienced, or specialist clinician did not go rst.) Participants were provided with opportunities to discuss any of the previously recorded responses.
All focus group sessions were audio recorded, transcribed verbatim and imported into NVivo software (12).Thematic analysis was conducted according to the stages outlined in Braune and Clarke (22).
Codes and subsequent themes were generated by a single researcher (non-clinical author) and were then veri ed with another researcher (clinical author).Participant transcriptions were labelled according to anonymised participant identi ers (in the form Ppt#),   The few individuals who did suggest that they used a classi cation system typically did not record the injury using the classi cation system, but just kept it in mind as they moved through the diagnostic process.
Diagnostic process occurs over a long period of time The diagnostic process was described as a period of data collection which changed and adapted as it progressed, sometimes over weeks or months, rather than within in a single appointment.This process has been outlined in gure 1.The participants described prioritising information collected from the physiotherapist over that recorded using technological means.Most participants only considered technology-based diagnostic tests or referrals as a potential future option if the original assessments and rehabilitation were unsuccessful.This was best displayed in the following quote: Ppt #11: 'we might not go for an MRI, an MRI straight away.See how they get on over the next few weeks.
Um, and if they had any neurological symptoms, then look at the conduction studies' [Vignette 2]

Diagnostic test choices in uenced by factors beyond objective markers associated with the patient injury
The regular trade-off between the idealistic and realistic when it came to carrying out tests and prescribed rehabilitation was another emergent theme of the data.Cost was the most frequently mentioned limiting factor to carrying out tests or exploring the future use of 3D motion capture.Tied in with cost was time; both the time for carrying out the tests and general appointments but also, should referrals be needed for the patient to access the test, the time for them to move through the waiting list.This balancing act between the needs of the patient in the vignettes, and real-life factors, e.g.patient waiting times, was a common point of discussion.
Sports ability, goals of patient, and in some cases the goals of parents and family, all in uenced the the selection of diagnostic tests.Patients performing sport at a higher level were more likely to have referrals for technology-based objective testing in a shorter time frame than those who only played at an informal settings, summed up in the following comment: Ppt #9: 'subjective factors will, will have an in uence on that, in terms of how sporty he is, and how, uh, how high-level he wants to be with that, as to whether I would pursue that further in terms of Planning for prognosis in uenced by factors beyond assessment ndings Many of the factors identi ed were directly linked to the injury or how the patient recovered, such as 'severity of pain in the initial stages' and 'how quickly he gets his range back' [Ppt #18 -Vignette 2].A wide range of additional factors were considered and prioritised in the prognosis assessments, namely age-related psychosocial in uences and subjective assessment related to social situation and family relationships.Gender/Sex bias was explicit.The teenage female vignettes were linked to poorer prognosis because 'They've got, you know, hormonal, hormonal changes going on, they've got loads going on in life.' [Ppt #18 -Vignette 1] which was suggested to in uence their likelihood to carry out the recommended rehabilitation faithfully.There were several comments about young girls' compliance and prognosis, the following comment best sums up these discussions: Ppt #18: '[teenage girls] are most likely to present with hypermobility and multi-directional instability in their shoulders.They're also the ones that most evidently, we know are most problematic to treat because they show signs of voluntary instability.They're the ones that we don't want to operate on.We don't want anybody to operate on.They're also poorly compliant, poor attenders and tricky.

' [Vignette 1]
There was some discussion surrounding psychosocial factors affecting the male vignette, but these were much less frequently mentioned and predominantly about apprehension to regain movement.Although this was not discussed further by any of the other physiotherapists in the group.
The physiotherapist pre-existing knowledge and notion of whether the treatment was likely to be effective was another factor which in uenced prognosis.This was particularly relevant to some groups for the injured male rugby player vignette, whereby the statistical likelihood of the shoulder injury occurring again was discussed: Ppt 7: 'Uh, but we know from research that given his age, and the fact that he's male, and he's sporty… Uh, I think he's sporty, um, that there is likely to be a recurrence.And so, I'd have that in the back of my mind really.At that age I think it's like over 90%, so…' [ Vignette 2] This made up one of the few examples of literature or data supporting the answers given in the focus groups.
Trust in staff relationships Within the focus groups there was a general theme of trust within the department and suspicion regarding individuals who were outside of that group.This was true for both external physiotherapists and members of different departments within the hospital environment.This was expressed in a number of different ways.
General distrust of individuals or modes of medicine used outside of the department.
Distrust was common when the participants discussed medical professionals outside of their department in relation to the patient vignettes.This was expressed through active discussion of unwillingness to trust other healthcare professionals' assessments or reports.The physiotherapists in the focus groups described additional checks which they would undertake due to them not trusting other professionals' practices and abilities.One physiotherapist described wanting to undertake a concussion test in addition to their standard assessments PPt #20: 'because I've had a few head injury guys that come in, like tackles or falls and things who end up being a shoulder but having been feeling quite sick and no one's actually checked.' [Vignette 2] While another described wanting to repeat some of the checks provided in the vignette to con rm the data which they had been given: PPt #20: 'I'd probably redo the Beighton score as well, make sure I agree with that scoring.' Facilitator: 'Why would you do the Beighton score?' PPt #20: 'Just so that then it's uh, I guess it's who's, who's referred.If they've been referred from the GP, um, how often are they doing that?' It is important to note, however, that where patients' situations were judged to need or bene t from external assessment or referrals, it did not stop the participants from stating that they would refer as soon as it was needed.For example: Ppt #7 'If he's a, you know, really keen sportsman, this is his career, uh, potentially, then I'm going to refer him straight away for an assessment on the understanding that most likely we'll be rehabbing you for three months.' Unity within the department This distrust, however, was generally absent within the groups themselves and very few members disagreed with anything which was said by their colleagues.This was verbally and structurally apparent in the construction of the group discussion.Participants tended to structure their response as a group rather than a series of individuals.When the participants responded to questions, while the rst person to speak tended to answer in detail, the following responses were generally much shorter and tended to be structured as: an agreement of the former participants' comments -often without clarifying which aspects they were agreeing with -, then an additional small detail or element which they had noticed.In some cases, though these were less common, some participants only agreed and contributed nothing else.
Groups often had one person who was a reference point for other members when they were unsure.These individuals, who tended to give much longer, detailed answers in the focus-groups, were typically senior gures within the department and with whom they consulted on a regular basis for advice regarding patients.
Facilitator And is any of this informed by any clinical pathways or best practice guidelines?This was consistent with the trend or participants not looking to pursue the use of technology unless it was necessary.Only one individual suggested that they would use it in one of the scenarios.Only two individuals described personal experience of using 3D motion capture, and many others speci ed that their training had not covered the method at all.In some cases of discussion, participants identi ed potential bene ts of 3D motion cap for their practice.
Rejection of 3D motion capture was justi ed with key concerns held against the technology.Concerns were linked to a lack of knowledge which extended to nearly every aspect of discussion including the technology itself, output it produces, the process of accessing and how it was established within the wider health service and clinical setting.
Technologically-based objective tests were described as being 'lovely and because it would take away any question, but it doesn't form part of our practice that we can have [Ppt #25 -Vignette 2', and the participants emphasised that they currently only use them when there are signi cant concerns or if initial attempts have failed.
Associated with the uncertainty were concerns regarding the accuracy and usability of the 3D motion capture technology from, as discussed in this comment here: Other concerns raised included suitably of staff training for interpreting the results and reservations about the bene ts of the additional data for the diagnostic process.Several participants showed an interest and willingness to investigate and try 3D motion capture, although in these cases participants often had inaccurate information or expectations regarding the system performance and capabilities.
Participants conceptualised integrating it into their practice and derived potential bene ts, best presented in this comment: PPt #20: 'If you had a machine or a computer system that they walked into a room and they said that my symptoms come on when I do this, they did that and then the computer says this is the problem and this is what you do, that would be amazing.

[Vignette 1]
Participants also expressed a willingness to learn more about the method to make a better-informed judgement.
PPt #23: 'It would be nice to get more experience of using it I guess.' [Vignette 2] Participants suggested that while there were mixed responses and concerns regarding 3D motion capture, further training and education regarding the techniques and outputs, could positively in uence their decision to use this mode of analysis in the future.

Discussion
The aim of this study was to elicit the types of information used to make clinical decisions, with the longterm goal of designing and developing appropriate decision support technologies for the assessment and management of children with shoulder instability.A fundamental requirement for development and implementation of a DDSS is to have explicit clinical decision-making processes.It is also important that DDSS are developed in partnership with the clinical end user from an early stage to facilitate use in a clinical environment (19).Within our study it was identi ed that there is no common structured approach towards assessment and diagnosis, therefore limiting the ability to develop a DDSS around current practice.The data con rmed that participants were not aware of existing classi cation systems (23).An agreed framework comprised of well-de ned terms and precise language is important for appropriately diagnosing patients and allocating treatment.Since a notable number suggested they did not know any classi cation methods, discussion about reasons for not using them was not common within the focus groups.The use of research to justify the decision to not use classi cation systems was hardly discussed, with the majority of participants suggesting that they did not know enough about them to consider using them in practice.Whilst further education and training may raise awareness regarding existing classi cation systems and frameworks, it is unlikely to increase their use in clinical practice.It is possible that existing classi cation systems are not suitable for clinical practice, as they are often complex and not based on accurate physiological processes (24).It is therefore important to establish an agreed language and systematic framework regarding diagnosis, before a DDSS can be implemented.Future work may look to draw upon terminologies and classi cation process associated with frameworks and such as the ICF ( 25) when mapping factors used for diagnosis in shoulder instability.
The goal of a DDSS should be to reduce the time taken to formal diagnosis.The time taken to reach a diagnosis in a developing child with shoulder instability is excessive and existing clinical assessment methods may not be suitable for accurately identifying etiological causes during the diagnostic process.The delayed time in diagnosis in current practice may stem from, and be compounded by, the lack of an agreed framework, limitations of current clinical assessment methods and, duplication of effort e.g.repeating clinical tests between practitioners.Development of a DDSS based on current practice would likely have limited accuracy and effectiveness.Current assessment methods are based predominantly on subjective reports by the patient and measurements or specialist clinical tests performed by the physiotherapist.Subjective reporting can be subject to recall bias (26) and clinical scales or orthopaedic tests lack sensitivity and speci city (27,28).Clinical decision-making processes based on these are therefore likely to be prone to error.A DDSS may mitigate for current practice that seems to operate on a trial and error-based system, informed by untested assumptions regarding physiological processes.There were no systematic processes or objective criteria for onward referral or investigations.Decisions regarding onward referral or investigations were usually driven by a failure of the patient to progress with physiotherapy, indicating this may not have been the correct treatment pathway.Given the limitations of existing assessment methods, a DDSS may be better suited signposting clinicians to additional investigations or measurement methods which could improve diagnostic accuracy.It is important however that the recommendations offered by the DDSS are re ective of the real-world clinical environments, t within the work ow of the clinician and are perceived as useful (29).The trade-off between perceived usefulness and effort are known to affect adoption of novel technology (30), alongside associated costs.When combined with further training and education, use of a DDSS can result in clinicians changing practice, resulting in the use of more appropriate technology for the assessment and management of the upper limb (18).Three-dimensional motion analysis and additional imaging has been shown to improve diagnostic accuracy in shoulder instability ( 6), yet, several barriers to using this technology were identi ed, namely lack of knowledge, perceived usefulness, access and cost.These were used to justify favouring the use of physiotherapist-based tests and assessments as standard practice instead of technology-based tests: Ppt #23: 'But if you can identify that with a naked eye um, and then um, look to treat and change that, then actually you're spending a lot of money videoing something that hopefully we dictate and write down.

' [Vignette 1]
The approach of the participant in one group changed when they were able to consider an 'ideal' situation rather than one which re ected their work environment.Although therapist were willing to use a variety of technology and assessments, even with tests that they were not familiar with, suggesting that there is a risk that referral to specialist test can be inappropriate.
Ppt #25: 'And again also in ideal world, you'd test everything, won't you?' [Vignette 1] Clinicians were sceptical of new unfamiliar technology and individuals or modes of medicine outside of the department suggesting the importance of early stakeholder involvement in developing the DDSS (29).Further, a DDSS may also need to support/educate the therapist with selecting appropriate tests essential to underpin accurate diagnosis (30).
Use of more objective measures, derived from technology, and used alongside an appropriate DDSS may reduce bias and the negative effects on patient outcomes.Due to the limitations of existing methods, there are inherent risks and decision making can be biased.This was evident across several of the themes identi ed and have been summarised in (table 2).Diagnostic process occurs over a long period of time

•
Diagnostic processes involved a wide range of tests and rehabilitation methods.Physiotherapy was often perceived to be the correct starting place for patients to try 'a few treatment sessions before [they] started considering those other investigations'.

•
There was a desire to see if they could enact change within the patient during a physiotherapy appointment, indicting there was a perceived role for physiotherapy Diagnostic test choices in uenced by factors beyond objective markers associated with the patient injury • Time, access and cost were perceived as barriers to additional diagnostic tests which may be bene cial to patients

•
Barriers used to justify prioritising physiotherapist-based tests and assessments as standard practice instead of technology-based tests.

•
Prioritised the information collected from the physiotherapist over that using technological means.

•
Participants with higher levels of activity, more likely to have referrals for technology-based objective testing in a shorter time frame.

•
Tied in with this was an example where despite having similar levels of activity between male and female vignettes, the male vignette was only offered onward referral (gender bias).
Planning for prognosis is in uenced by a number of factors

•
Diagnostic processes and decisions regarding management in uenced by previous clinical experience and knowledge whether the treatment was likely to be effective.

•
Psychosocial in uences were generally perceived to be only relevant for the female vignettes in a negative way.

Knowledge and attitudes towards novel technologies for facilitating assessment and clinical decision making
Trust in staff relationships General distrust of individuals or modes of medicine used outside of the department

•
Evident in discussions regarding medical professionals outside of their department in relation to the patient vignettes.

•
The physiotherapists in the focus groups described additional checks which they would undertake due to them not trusting other professionals' practices and abilities.

Trust in relationships
Unity within the department

•
Very few disagreements within the departments.Verbally con rmed and structurally apparent in the construction of the group discussions.

•
Evidence of a medical hierarchy within the group and practice.
Lack of knowledge and rejection of 3D motion • Lack of knowledge limiting participants using technology which could facilitate decision making.

capture
• General trend for the participants to not pursue the use of any technology unless it was perceived as necessary.

•
Perception that having additional information or data will not bene t the diagnostic process if cannot be understood or usefully integrated into the current practice.
A range of factors beyond the patient injury in uenced both patient assessment and prognosis.
Psychosocial factors were perceived to negatively affect prognosis, mainly for the teenage female vignettes.It is important to note there were no explicit psychosocial factors stated in the vignettes.Whilst poor prognosis may be associated with psychological problems (31,32), this is not unique to the female gender and the current assumption is founded on cient epidemiological data.It was also noted that the decision to refer onwards was only offered to the male vignette.Diagnostic processes and decisions regarding management were therefore in uenced by previous clinical experience and knowledge whether the treatment was likely to be effective.Overall, this may re ect clinical reasoning processes based around hypo-deductive reasoning or pattern recognition which is prone to error and may compound biases (33)(34)(35).It is likely that some of the biases observed are common between physiotherapists and are embedded within the training at degree level, within the place of work and wider training opportunities such as continuing professional development.This was evident in the predominance of group responses and the general distrust of people outside of their group.
Disagreements were rare and usually only covered one element of the diagnosis.This behaviour is re ective of the groupthink phenomenon (36) and can result in omission or exclusion of potentially important information or practices from outside the group.It is also possible that clinical practice is inherited from or in uenced by more senior/experienced staff members or those to perceived to be higher in the medical hierarchy such as consultants (37).This was also evident in the structure of the focus groups, whereby one or two key members were used as a reference point in times of uncertainty, usually a more senior gure, and practice was referenced around continuing professional development courses they attended rather than evidence-based guidelines.A DDSS may therefore be used to present clinicians with suggestions of objective criteria for assessment and management alongside differential diagnosis to be considered.DDSS are prone to bias if the training or reference datasets used are inappropriate or if the developers of DDSS include their bias into the system (38).Several systematic biases were identi ed in the assessment of paediatric shoulder instability, most notably regarding gender.In this study, the vignettes provided did not specify variations in socioeconomic backgrounds, ethnicity or other demographic information which may also be characteristics that are subject to bias.We are therefore unable to account for the impact of these features in decision making and their susceptibility to bias.An inability to appropriately understand the data used for decision making and identify sources bias can result in further propagation of bias as an inherent feature of the DDSS, negatively in uencing patient outcomes, rather than alerting the clinical end user of their bias in order to mitigate against it.This would limit the ability of the DDSS to provide an objective reference source for evaluation of clinical decision making.It is recognised that this requires pathways to be established and structured around predetermined criteria and algorithmic processes which currently do not exist.Further work is therefore needed to develop these processes and evaluate what effect variations in demographic characteristics have on clinical decision making for shoulder instability.
Limitations of the study Despite randomisation of participants to ensure the most experienced clinician did not lead and focus groups being set up to encourage individual speech, it is acknowledged that responses were structured as a group with little disagreement and usually in uenced by one or two more senior members of the group.
Use of the nominal focus group technique in already established groups, in which there are hierarchies, may therefore limit generation of individual ideas and discussion or disagreement.Whilst this was done to identify common practice at separate clinical sites, future work may look to use the nominal focus group in groups comprised of different clinical sites or departments.An aim of our study was to identify the information used for clinical decision making.We were unable to identify a minimum dataset or explicitly map the processes associated with assessment and management of paediatric shoulder instability.This may be due to omission of the last stage of the nominal focus group technique in which participants vote for the most important factors.Due to the variable practice between sites and levels of agreement within sites it is unlikely that this process would have generated the desired dataset.Further work is needed to identify agreed criteria used in decision making which can be matched against explicit decision-making processes.This may be achieved or informed further by Delphi technique, semistructured interviews or action research methodologies.Our sample was wholly comprised of physiotherapists based within a public health setting.It is recognised that patients with shoulder instability may present to and be managed by alternate healthcare professionals.It is therefore important to ensure any subsequent technology or decision support systems designed for use in clinical practice takes into consideration these factors and is transferable between services and professions.
On the basis of our ndings we have produced a concept map for development of a DDSS ( gure 2) and list of implications for development of an appropriate DDSS and associated software.

Conclusion And Implication For Ddss And Software Design
In order for a DDSS and associate to be developed, Agreed terminology, classi cation and de nition of terms within practice is required.Systematic approaches towards assessment, which can be codi ed and customised to match local practice are needed.An agreed minimum data set which is important in diagnosing paediatric shoulder instability and any area's which would bene t from further investigations or technological assessments need to be identi ed to improve diagnostic accuracy.

Ppt # 5
Nothing speci c.I've always gone to Ppt #7 when I have had… Ppt #7 [Laughs].Ppt #5 These di cult patients and got her opinion on it.Ppt #8 [Laughs].I've asked her as well.[Vignette 1]Typically, these gures of reference were the only individuals who, during the focus group, alluded to the use of research or evidence to support their points.Knowledge and attitudes towards novel technologies for facilitating assessment and clinical decision makingLack of knowledge and rejection of 3D motion capture Participants expressed a general lack of knowledge regarding 3D motion capture which resulted in 3D motion capture being nearly completely rejected as a potential diagnostic test, best summarised by the following statement: Ppt #10 'I don't know enough about it so I wouldn't want, feel con dent to recommend it.'[Vignette 1] Twitter: @eddequincey LinkedIn: http://uk.linkedin.com/in/eddequinceyORCID: https://orcid.org/0000-0002-3824-4444Dr Anand Pandyan a.d.pandyan@keele.ac.ukORCID: https://orcid.org/0000-0002-2180-197XTwitter: @AnandDPandyan

Figures
Figures

Table
Patient is a 16-year-old female presenting with worsening right shoulder pain.Recurrent episodes of instability/ partial shoulder displacement for the last 6 years.Not sure about the direction of instability.Competitive netball and swimming since age 12 with onset of pain at age 14.Had multiple physiotherapy sessions over the years for managing exacerbations.Referred by GP for recent worsening of shoulder pain.Patient is a 14 year old male.Contact injury to left shoulder 3 days ago during a rugby match.Tackled opposing player with arm out, felt shoulder come out of place, reduced by itself.Presented to the emergency department.X-ray nothing abnormal detected.No previous shoulder injuries.Referred for rehabilitation.Patient is a 17 year old female referred for recent episode of shoulder instability and pain following collision in basketball 2 months ago.Felt shoulder pop out and in when diving for a ball on the ground.Did not attend emergency department.Unable to recall previous signi cant episodes of trauma.History of similar feelings previously but less severe.Unclear around the level and direction of displacement.Previous episodes associated with normal daily tasks and sports but did not affect activity or participation.Referred by GP to Physiotherapy for shoulder pain and queried shoulder dislocation.Separate referral to orthopedic consultant pending appointment date.
•Beighton score 5/9 (Bilat elbows, knees and hands at to oor)*• Full active range of movement with pain end of range elevation.

Table 2 .
Themes and associated list of biases identi ed within the data