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Bone & Joint Open
Vol. 5, Issue 9 | Pages 768 - 775
18 Sep 2024
Chen K Dong X Lu Y Zhang J Liu X Jia L Guo Y Chen X

Aims

Surgical approaches to cervical ossification of the posterior longitudinal ligament (OPLL) remain controversial. The purpose of the present study was to analyze and compare the long-term neurological recovery following anterior decompression with fusion (ADF) and posterior laminectomy and fusion with bone graft and internal fixation (PLF) based on > ten-year follow-up outcomes in a single centre.

Methods

Included in this retrospective cohort study were 48 patients (12 females; mean age 55.79 years (SD 8.94)) who were diagnosed with cervical OPLL, received treatment in our centre, and were followed up for 10.22 to 15.25 years. Of them, 24 patients (six females; mean age 52.88 years (SD 8.79)) received ADF, and the other 24 patients (five females; mean age 56.25 years (SD 9.44)) received PLF. Clinical data including age, sex, and the OPLL canal-occupying ratio were analyzed and compared. The primary outcome was Japanese Orthopaedic Association (JOA) score, and the secondary outcome was visual analogue scale neck pain.


Bone & Joint Open
Vol. 5, Issue 8 | Pages 697 - 707
22 Aug 2024
Raj S Grover S Spazzapan M Russell B Jaffry Z Malde S Vig S Fleming S

Aims. The aims of this study were to describe the demographic, socioeconomic, and educational factors associated with core surgical trainees (CSTs) who apply to and receive offers for higher surgical training (ST3) posts in Trauma & Orthopaedics (T&O). Methods. Data collected by the UK Medical Education Database (UKMED) between 1 January 2014 and 31 December 2019 were used in this retrospective longitudinal cohort study comprising 1,960 CSTs eligible for ST3. The primary outcome measures were whether CSTs applied for a T&O ST3 post and if they were subsequently offered a post. A directed acyclic graph was used for detecting confounders and adjusting logistic regression models to calculate odds ratios (ORs), which assessed the association between the primary outcomes and relevant exposures of interest, including: age, sex, ethnicity, parental socioeconomic status (SES), domiciliary status, category of medical school, Situational Judgement Test (SJT) scores at medical school, and success in postgraduate examinations. This study followed STROBE guidelines. Results. Compared to the overall cohort of CSTs, females were significantly less likely to apply to T&O (OR 0.37, 95% CI 0.30 to 0.46; n = 155/720 female vs n = 535/1,240 male; p < 0.001). CSTs who were not UK-domiciled prior to university were nearly twice as likely to apply to T&O (OR 1.99, 95% CI 1.39 to 2.85; n = 50/205 vs not UK-domiciled vs n = 585/1,580 UK-domiciled; p < 0.001). Age, ethnicity, SES, and medical school category were not associated with applying to T&O. Applicants who identified as ‘black and minority ethnic’ (BME) were significantly less likely to be offered a T&O ST3 post (OR 0.70, 95% CI 0.51 to 0.97; n = 165/265 BME vs n = 265/385 white; p = 0.034). Differences in age, sex, SES, medical school category, and SJT scores were not significantly associated with being offered a T&O ST3 post. Conclusion. There is an evident disparity in sex between T&O applicants and an ethnic disparity between those who receive offers on their first attempt. Further high-quality, prospective research in the post-COVID-19 pandemic period is needed to improve equality, diversity, and inclusion in T&O training. Cite this article: Bone Jt Open 2024;5(8):697–707


Bone & Joint Research
Vol. 13, Issue 4 | Pages 193 - 200
23 Apr 2024
Reynolds A Doyle R Boughton O Cobb J Muirhead-Allwood S Jeffers J

Aims. Manual impaction, with a mallet and introducer, remains the standard method of installing cementless acetabular cups during total hip arthroplasty (THA). This study aims to quantify the accuracy and precision of manual impaction strikes during the seating of an acetabular component. This understanding aims to help improve impaction surgical techniques and inform the development of future technologies. Methods. Posterior approach THAs were carried out on three cadavers by an expert orthopaedic surgeon. An instrumented mallet and introducer were used to insert cementless acetabular cups. The motion of the mallet, relative to the introducer, was analyzed for a total of 110 strikes split into low-, medium-, and high-effort strikes. Three parameters were extracted from these data: strike vector, strike offset, and mallet face alignment. Results. The force vector of the mallet strike, relative to the introducer axis, was misaligned by an average of 18.1°, resulting in an average wasted strike energy of 6.1%. Furthermore, the mean strike offset was 19.8 mm from the centre of the introducer axis and the mallet face, relative to the introducer strike face, was misaligned by a mean angle of 15.2° from the introducer strike face. Conclusion. The direction of the impact vector in manual impaction lacks both accuracy and precision. There is an opportunity to improve this through more advanced impaction instruments or surgical training. Cite this article: Bone Joint Res 2024;13(4):193–200


Bone & Joint Open
Vol. 4, Issue 12 | Pages 970 - 979
19 Dec 2023
Kontoghiorghe C Morgan C Eastwood D McNally S

Aims

The number of females within the speciality of trauma and orthopaedics (T&O) is increasing. The aim of this study was to identify: 1) current attitudes and behaviours of UK female T&O surgeons towards pregnancy; 2) any barriers faced towards pregnancy with a career in T&O surgery; and 3) areas for improvement.

Methods

This is a cross-sectional study using an anonymous 13-section web-based survey distributed to female-identifying T&O trainees, speciality and associate specialist surgeons (SASs) and locally employed doctors (LEDs), fellows, and consultants in the UK. Demographic data was collected as well as closed and open questions with adaptive answering relating to attitudes towards childbearing and experiences of fertility and complications associated with pregnancy. A descriptive data analysis was carried out.


The Bone & Joint Journal
Vol. 105-B, Issue 10 | Pages 1060 - 1069
1 Oct 2023
Holleyman RJ Jameson SS Reed M Meek RMD Khanduja V Hamer A Judge A Board T

Aims

This study describes the variation in the annual volumes of revision hip arthroplasty (RHA) undertaken by consultant surgeons nationally, and the rate of accrual of RHA and corresponding primary hip arthroplasty (PHA) volume for new consultants entering practice.

Methods

National Joint Registry (NJR) data for England, Wales, Northern Ireland, and the Isle of Man were received for 84,816 RHAs and 818,979 PHAs recorded between April 2011 and December 2019. RHA data comprised all revision procedures, including first-time revisions of PHA and any subsequent re-revisions recorded in public and private healthcare organizations. Annual procedure volumes undertaken by the responsible consultant surgeon in the 12 months prior to every index procedure were determined. We identified a cohort of ‘new’ HA consultants who commenced practice from 2012 and describe their rate of accrual of PHA and RHA experience.


Bone & Joint Open
Vol. 4, Issue 9 | Pages 696 - 703
11 Sep 2023
Ormond MJ Clement ND Harder BG Farrow L Glester A

Aims. The principles of evidence-based medicine (EBM) are the foundation of modern medical practice. Surgeons are familiar with the commonly used statistical techniques to test hypotheses, summarize findings, and provide answers within a specified range of probability. Based on this knowledge, they are able to critically evaluate research before deciding whether or not to adopt the findings into practice. Recently, there has been an increased use of artificial intelligence (AI) to analyze information and derive findings in orthopaedic research. These techniques use a set of statistical tools that are increasingly complex and may be unfamiliar to the orthopaedic surgeon. It is unclear if this shift towards less familiar techniques is widely accepted in the orthopaedic community. This study aimed to provide an exploration of understanding and acceptance of AI use in research among orthopaedic surgeons. Methods. Semi-structured in-depth interviews were carried out on a sample of 12 orthopaedic surgeons. Inductive thematic analysis was used to identify key themes. Results. The four intersecting themes identified were: 1) validity in traditional research, 2) confusion around the definition of AI, 3) an inability to validate AI research, and 4) cautious optimism about AI research. Underpinning these themes is the notion of a validity heuristic that is strongly rooted in traditional research teaching and embedded in medical and surgical training. Conclusion. Research involving AI sometimes challenges the accepted traditional evidence-based framework. This can give rise to confusion among orthopaedic surgeons, who may be unable to confidently validate findings. In our study, the impact of this was mediated by cautious optimism based on an ingrained validity heuristic that orthopaedic surgeons develop through their medical training. Adding to this, the integration of AI into everyday life works to reduce suspicion and aid acceptance. Cite this article: Bone Jt Open 2023;4(9):696–703


Bone & Joint Open
Vol. 4, Issue 8 | Pages 602 - 611
21 Aug 2023
James HK Pattison GTR Griffin J Fisher JD Griffin DR

Aims

To evaluate if, for orthopaedic trainees, additional cadaveric simulation training or standard training alone yields superior radiological and clinical outcomes in patients undergoing dynamic hip screw (DHS) fixation or hemiarthroplasty for hip fracture.

Methods

This was a preliminary, pragmatic, multicentre, parallel group randomized controlled trial in nine secondary and tertiary NHS hospitals in England. Researchers were blinded to group allocation. Overall, 40 trainees in the West Midlands were eligible: 33 agreed to take part and were randomized, five withdrew after randomization, 13 were allocated cadaveric training, and 15 were allocated standard training. The intervention was an additional two-day cadaveric simulation course. The control group received standard on-the-job training. Primary outcome was implant position on the postoperative radiograph: tip-apex distance (mm) (DHS) and leg length discrepancy (mm) (hemiarthroplasty). Secondary clinical outcomes were procedure time, length of hospital stay, acute postoperative complication rate, and 12-month mortality. Procedure-specific secondary outcomes were intraoperative radiation dose (for DHS) and postoperative blood transfusion requirement (hemiarthroplasty).


Aims

Ankle fracture fixation is commonly performed by junior trainees. Simulation training using cadavers may shorten the learning curve and result in a technically superior surgical performance.

Methods

We undertook a preliminary, pragmatic, single-blinded, multicentre, randomized controlled trial of cadaveric simulation versus standard training. Primary outcome was fracture reduction on postoperative radiographs.


Bone & Joint Research
Vol. 12, Issue 7 | Pages 447 - 454
10 Jul 2023
Lisacek-Kiosoglous AB Powling AS Fontalis A Gabr A Mazomenos E Haddad FS

The use of artificial intelligence (AI) is rapidly growing across many domains, of which the medical field is no exception. AI is an umbrella term defining the practical application of algorithms to generate useful output, without the need of human cognition. Owing to the expanding volume of patient information collected, known as ‘big data’, AI is showing promise as a useful tool in healthcare research and across all aspects of patient care pathways. Practical applications in orthopaedic surgery include: diagnostics, such as fracture recognition and tumour detection; predictive models of clinical and patient-reported outcome measures, such as calculating mortality rates and length of hospital stay; and real-time rehabilitation monitoring and surgical training. However, clinicians should remain cognizant of AI’s limitations, as the development of robust reporting and validation frameworks is of paramount importance to prevent avoidable errors and biases. The aim of this review article is to provide a comprehensive understanding of AI and its subfields, as well as to delineate its existing clinical applications in trauma and orthopaedic surgery. Furthermore, this narrative review expands upon the limitations of AI and future direction. Cite this article: Bone Joint Res 2023;12(7):447–454


Bone & Joint Open
Vol. 3, Issue 6 | Pages 502 - 509
20 Jun 2022
James HK Griffin J Pattison GTR

Aims

To identify a core outcome set of postoperative radiographic measurements to assess technical skill in ankle fracture open reduction internal fixation (ORIF), and to validate these against Van der Vleuten’s criteria for effective assessment.

Methods

An e-Delphi exercise was undertaken at a major trauma centre (n = 39) to identify relevant parameters. Feasibility was tested by two authors. Reliability and validity was tested using postoperative radiographs of ankle fracture operations performed by trainees enrolled in an educational trial (IRCTN 20431944). To determine construct validity, trainees were divided into novice (performed < ten cases at baseline) and intermediate groups (performed ≥ ten cases at baseline). To assess concurrent validity, the procedure-based assessment (PBA) was considered the gold standard. The inter-rater and intrarater reliability was tested using a randomly selected subset of 25 cases.


Bone & Joint Open
Vol. 2, Issue 10 | Pages 893 - 899
26 Oct 2021
Ahmed M Hamilton LC

Orthopaedics has been left behind in the worldwide drive towards diversity and inclusion. In the UK, only 7% of orthopaedic consultants are female. There is growing evidence that diversity increases innovation as well as patient outcomes. This paper has reviewed the literature to identify some of the common issues affecting female surgeons in orthopaedics, and ways in which we can address them: there is a wealth of evidence documenting the differences in the journey of men and women towards a consultant role. We also look at lessons learned from research in the business sector and the military. The ‘Hidden Curriculum’ is out of date and needs to enter the 21st century: microaggressions in the workplace must be challenged; we need to consider more flexible training options and support trainees who wish to become pregnant; mentors, both male and female, are imperative to provide support for trainees. The world has changed, and we need to consider how we can improve diversity to stay relevant and effective.

Cite this article: Bone Jt Open 2021;2-10:893–899.


Bone & Joint Open
Vol. 2, Issue 3 | Pages 181 - 190
1 Mar 2021
James HK Gregory RJH

The imminent introduction of the new Trauma & Orthopaedic (T&O) curriculum, and the implementation of the Improving Surgical Training initiative, reflect yet another paradigm shift in the recent history of trauma and orthopaedic training. The move to outcome-based training without time constraints is a radical departure from the traditional time-based structure and represents an exciting new training frontier. This paper summarizes the history of T&O training reform, explains the rationale for change, and reflects on lessons learnt from the past. Cite this article: Bone Jt Open 2021;2-3:181–190


Bone & Joint Open
Vol. 2, Issue 2 | Pages 111 - 118
8 Feb 2021
Pettit M Shukla S Zhang J Sunil Kumar KH Khanduja V

Aims

The ongoing COVID-19 pandemic has disrupted and delayed medical and surgical examinations where attendance is required in person. Our article aims to outline the validity of online assessment, the range of benefits to both candidate and assessor, and the challenges to its implementation. In addition, we propose pragmatic suggestions for its introduction into medical assessment.

Methods

We reviewed the literature concerning the present status of online medical and surgical assessment to establish the perceived benefits, limitations, and potential problems with this method of assessment.


Bone & Joint Open
Vol. 1, Issue 10 | Pages 645 - 652
19 Oct 2020
Sheridan GA Hughes AJ Quinlan JF Sheehan E O'Byrne JM

Aims. We aim to objectively assess the impact of COVID-19 on mean total operative cases for all indicative procedures (as outlined by the Joint Committee on Surgical Training (JCST)) experienced by orthopaedic trainees in the deanery of the Republic of Ireland. Subjective experiences were reported for each trainee using questionnaires. Methods. During the first four weeks of the nationwide lockdown due to COVID-19, the objective impact of the pandemic on each trainee’s surgical caseload exposure was assessed using data from individual trainee logbook profiles in the deanery of the Republic of Ireland. Independent predictor variables included the trainee grade (ST 3 to 8), the individual trainee, the unit that the logbook was reported from, and the year in which the logbook was recorded. We used the analysis of variance (ANOVA) test to assess for any statistically significant predictor variables. The subjective experience of each trainee was captured using an electronic questionnaire. Results. The mean number of total procedures per trainee over four weeks was 36.8 (7 to 99; standard deviation (SD) 19.67) in 2018, 40.6 (6 to 81; SD 17.90) in 2019, and 18.3 (3 to 65; SD 11.70) during the pandemic of 2020 (p = 0.043). Significant reductions were noted for all elective indicative procedures, including arthroplasty (p = 0.019), osteotomy (p = 0.045), nerve decompression (p = 0.024) and arthroscopy (p = 0.024). In contrast, none of the nine indicative procedures for trauma were reduced. There was a significant inter-unit difference in the mean number of total cases (p = 0.029) and indicative cases (p = 0.0005) per trainee. We noted that 7.69% (n = 3) of trainees contracted COVID-19. Conclusion. During the COVID-19 pandemic, the mean number of operative cases per trainee has been significantly reduced for four of the 13 indicative procedures, as outlined by the JCST. Reassignment of trainees to high-volume institutions in the future may be a plausible approach to mitigate significant training deficits in those trainees worst impacted by the reduction in operative exposure


Bone & Joint Open
Vol. 1, Issue 9 | Pages 594 - 604
24 Sep 2020
James HK Pattison GTR Griffin J Fisher JD Griffin DR

Aims. To develop a core outcome set of measurements from postoperative radiographs that can be used to assess technical skill in performing dynamic hip screw (DHS) and hemiarthroplasty, and to validate these against Van der Vleuten’s criteria for effective assessment. Methods. A Delphi exercise was undertaken at a regional major trauma centre to identify candidate measurement items. The feasibility of taking these measurements was tested by two of the authors (HKJ, GTRP). Validity and reliability were examined using the radiographs of operations performed by orthopaedic resident participants (n = 28) of a multicentre randomized controlled educational trial (ISRCTN20431944). Trainees were divided into novice and intermediate groups, defined as having performed < ten or ≥ ten cases each for DHS and hemiarthroplasty at baseline. The procedure-based assessment (PBA) global rating score was assumed as the gold standard assessment for the purposes of concurrent validity. Intra- and inter-rater reliability testing were performed on a random subset of 25 cases. Results. In total, 327 DHS and 248 hemiarthroplasty procedures were performed by 28 postgraduate year (PGY) 3 to 5 orthopaedic trainees during the 2014 to 2015 surgical training year at nine NHS hospitals in the West Midlands, UK. Overall, 109 PBAs were completed for DHS and 80 for hemiarthroplasty. Expert consensus identified four ‘final product analysis’ (FPA) radiological parameters of technical success for DHS: tip-apex distance (TAD); lag screw position in the femoral head; flushness of the plate against the lateral femoral cortex; and eight-cortex hold of the plate screws. Three parameters were identified for hemiarthroplasty: leg length discrepancy; femoral stem alignment; and femoral offset. Face validity, content validity, and feasibility were excellent. For all measurements, performance was better in the intermediate compared with the novice group, and this was statistically significant for TAD (p < 0.001) and femoral stem alignment (p = 0.023). Concurrent validity was poor when measured against global PBA score. This may be explained by the fact that they are measuring difference facets of competence. Intra-and inter-rater reliability were excellent for TAD, moderate for lag screw position (DHS), and moderate for leg length discrepancy (hemiarthroplasty). Use of a large multicentre dataset suggests good generalizability of the results to other settings. Assessment using FPA was time- and cost-effective compared with PBA. Conclusion. Final product analysis using post-implantation radiographs to measure technical skill in hip fracture surgery is feasible, valid, reliable, and cost-effective. It can complement traditional workplace-based assessment for measuring performance in the real-world operating room . It may have particular utility in competency-based training frameworks and for assessing skill transfer from the simulated to live operating theatre. Cite this article: Bone Joint Open 2020;1-9:594–604


Bone & Joint Open
Vol. 1, Issue 8 | Pages 494 - 499
18 Aug 2020
Karia M Gupta V Zahra W Dixon J Tayton E

Aims

The aim of this study is to determine the effects of the UK lockdown during the COVID-19 pandemic on the orthopaedic admissions, operations, training opportunities, and theatre efficiency in a large district general hospital.

Methods

The number of patients referred to the orthopaedic team between 1 April 2020 and 30 April 2020 were collected. Other data collected included patient demographics, number of admissions, number and type of operations performed, and seniority of primary surgeon. Theatre time was collected consisting of anaesthetic time, surgical time, time to leave theatre, and turnaround time. Data were compared to the same period in 2019.


Bone & Joint Open
Vol. 1, Issue 5 | Pages 103 - 114
13 May 2020
James HK Gregory RJH Tennent D Pattison GTR Fisher JD Griffin DR

Aims

The primary aim of the survey was to map the current provision of simulation training within UK and Republic of Ireland (RoI) trauma and orthopaedic (T&O) specialist training programmes to inform future design of a simulation based-curriculum. The secondary aims were to characterize; the types of simulation offered to trainees by stage of training, the sources of funding for simulation, the barriers to providing simulation in training, and to measure current research activity assessing the educational impact of simulation.

Methods

The development of the survey was a collaborative effort between the authors and the British Orthopaedic Association Simulation Group. The survey items were embedded in the Performance and Opportunity Dashboard, which annually audits quality in training across several domains on behalf of the Speciality Advisory Committee (SAC). The survey was sent via email to the 30 training programme directors in March 2019. Data were retrieved and analyzed at the Warwick Clinical Trials Unit, UK.


Bone & Joint Open
Vol. 1, Issue 5 | Pages 98 - 102
6 May 2020
Das De S Puhaindran ME Sechachalam S Wong KJH Chong CW Chin AYH

The COVID-19 pandemic has disrupted all segments of daily life, with the healthcare sector being at the forefront of this upheaval. Unprecedented efforts have been taken worldwide to curb this ongoing global catastrophe that has already resulted in many fatalities. One of the areas that has received little attention amid this turmoil is the disruption to trainee education, particularly in specialties that involve acquisition of procedural skills. Hand surgery in Singapore is a standalone combined programme that relies heavily on dedicated cross-hospital rotations, an extensive didactic curriculum and supervised hands-on training of increasing complexity. All aspects of this training programme have been affected because of the cancellation of elective surgical procedures, suspension of cross-hospital rotations, redeployment of residents, and an unsustainable duty roster. There is a real concern that trainees will not be able to meet their training requirements and suffer serious issues like burnout and depression. The long-term impact of suspending training indefinitely is a severe disruption of essential medical services. This article examines the impact of a global pandemic on trainee education in a demanding surgical speciality. We have outlined strategies to maintain trainee competencies based on the following considerations: 1) the safety and wellbeing of trainees is paramount; 2) resource utilization must be thoroughly rationalized; 3) technology and innovative learning methods must supplant traditional teaching methods; and 4) the changes implemented must be sustainable. We hope that these lessons will be valuable to other training programs struggling to deliver quality education to their trainees, even as we work together to battle this global catastrophe.


Bone & Joint Open
Vol. 1, Issue 4 | Pages 47 - 54
2 Apr 2020
Al-Mohrej OA Elshaer AK Al-Dakhil SS Sayed AI Aljohar S AlFattani AA Alhussainan TS

Introduction. Studies have addressed the issue of increasing prevalence of work-related musculoskeletal (MSK) pain among different occupations. However, contributing factors to MSK pain have not been fully investigated among orthopaedic surgeons. Thus, this study aimed to approximate the prevalence and predictors of MSK pain among Saudi orthopaedic surgeons working in Riyadh, Saudi Arabia. Methods. A cross-sectional study using an electronic survey was conducted in Riyadh. The questionnaire was distributed through email among orthopaedic surgeons in Riyadh hospitals. Standardized Nordic questionnaires for the analysis of musculoskeletal symptoms were used. Descriptive measures for categorical and numerical variables were presented. Student’s t-test and Pearson’s χ2 test were used. The level of statistical significance was set at p ≤ 0.05. Results. The response rate was 80.3%, with a total number of 179 of Saudi orthopaedic surgeons (173 males and six females). Of our sample, 67.0% of the respondents complained of having MSK pain. The most commonly reported MSK pain was lower back (74.0%), followed by neck (58.2%). Age and body mass index were implicated in the development of more than one type of MSK pain. Increased years of experience (≥ 6 years) was linked to shoulder/elbow, lower back, and hip/thigh pain. Smoking is widely associated with lower back pain development, whereas physicians who do not smoke and exercise regularly reported fewer pain incidences. Excessive bending and twisting during daily practice have been correlated with increased neck pain. Conclusion. MSK pain was found to be common among Saudi orthopaedic surgeons. Further extensive research should be conducted to understand and analyze the risk factors involved and search for possible improvements to avoid further complications. However, ergonomics education during surgical training could be effective at modifying behaviors and reducing MSK pain manifestations


Bone & Joint Open
Vol. 1, Issue 3 | Pages 41 - 46
18 Mar 2020
Perry DC Arch B Appelbe D Francis P Spowart C Knight M

Introduction

There is widespread variation in the management of rare orthopaedic disease, in a large part owing to uncertainty. No individual surgeon or hospital is typically equipped to amass sufficient numbers of cases to draw robust conclusions from the information available to them. The programme of research will establish the British Orthopaedic Surgery Surveillance (BOSS) Study; a nationwide reporting structure for rare disease in orthopaedic surgery.

Methods

The BOSS Study is a series of nationwide observational cohort studies of pre-specified orthopaedic disease. All relevant hospitals treating the disease are invited to contribute anonymised case details. Data will be collected digitally through REDCap, with an additional bespoke software solution used to regularly confirm case ascertainment, prompt follow-up reminders and identify potential missing cases from external sources of information (i.e. national administrative data). With their consent, patients will be invited to enrich the data collected by supplementing anonymised case data with patient reported outcomes.

The study will primarily seek to calculate the incidence of the rare diseases under investigation, with 95% confidence intervals. Descriptive statistics will be used to describe the case mix, treatment variations and outcomes. Inferential statistical analysis may be used to analyze associations between presentation factors and outcomes. Types of analyses will be contingent on the disease under investigation.