Predictors of 5-Year Citation Rate in the Orthopaedic Sports Medicine Literature

The 100 most impactful articles in foot and ankle surgery: An altmetric analysis

Citation count and impact factor of the publishing journal are two historically utilized metrics to determine an article's impact in its research field. However, these metrics are limited given the rise in research dissemination through social media. Across other orthopedic specialties, the Altmetric Attention Score (AAS) has been used to determine which articles are most impactful. This study utilizes the AAS to highlight the 100 most impactful articles in foot and ankle surgery and determine if bibliometric factors and article characteristics are predictive of AAS. The AAS website was queried on a single day in September 2024 and 4,262 articles were retrieved. The top 100 relevant foot and ankle articles published after 2010 were ranked by AAS and analyzed for bibliometric factors, study design, and study subject. The median (IQR) AAS was 18 (14, 42.5). A majority of the top 100 impactful articles were published in the Journal of Foot and Ankle Surgery and Foot and Ankle Surgery. Most articles were original clinical research articles (54 %). Facebook and news mentions were positively correlated with AAS (p = 0.019, p < 0.0001, respectively) while other social media mentions had no significant relationship (p > 0.05). Study design and study subject were not significant predictors of AAS (p > 0.05). In conclusion, our study finds that, while citation count indicates an article's longitudinal impact, it does not correlate with AAS in foot and ankle surgery, which provides an immediate, dynamic metric to directly compare articles' impacts. Level of Evidence: Level IV.

Comparing Orthopaedic Randomized Control Trials Published in High-Impact Medical and Orthopaedic Journals

INTRODUCTION

Orthopaedic studies published in high-impact medical journals are often believed to have a high prevalence of negative or neutral results and possess methodological characteristics that may bias toward nonsurgical treatments. The purpose of this study was to compare study characteristics, methodologic quality, exposure, and outcome direction among orthopaedic randomized control trials (RCTs) published in high-impact medical and orthopaedic journals and to identify study attributes associated with greater impact.

METHODS

RCTs published between January 2010 and December 2020 in the five medical journals and 10 orthopaedic journals with the highest 5-year impact factors were analyzed. Inclusion criteria were RCTs reporting on orthopaedic surgical intervention compared with nonsurgical or less-invasive surgical procedures. Study characteristics, methodologic quality (Jadad scale), outcomes, and altmetric data were collected. Primary outcomes were categorized as positive (favoring surgical/more-extensive surgery), negative (favoring nonsurgical/less-extensive surgery), or neutral.

RESULTS

One hundred twenty-eight RCTs were analyzed; 26 from medical and 102 from orthopaedic journals. Studies published in medical journals included more authors ( P < 0.001), larger sample sizes ( P < 0.001), more institutions ( P < 0.001), and more often received funding ( P < 0.001). The average Jadad scale did not significantly differ between journals ( P = 0.14). The direction of the primary study outcome did not differ between journals ( P = 0.22). Average AAS and annual citation rates were higher in RCTs published in medical journals ( P < 0.001). Publication in a medical journal was the only covariate associated with higher annual citation rates ( P < 0.001) and AAS ( P < 0.001) on multivariable analyses.

DISCUSSION

High-impact medical journals do not publish orthopaedic RCTs with negative or neutral findings at a rate that significantly differs from orthopaedic journals. However, the higher impact and digital coverage of the studies published in medical journals may disproportionally influence the practices of nonorthopaedic providers. Raising awareness of critical findings published in orthopaedic journals may be particularly important for improving healthcare policies and orthopaedic referral patterns for musculoskeletal problems.

The Top 50 Most Cited Publications in Meniscus Research

Injuries to the menisci of the knee are common in orthopedic sports medicine. Bibliometric studies can identify the core literature on a topic and help further our collective knowledge for both clinical and educational purposes. The purpose of the current study was to (1) identify and describe the 50 most cited articles in meniscus research over an 80-year time period to capture a wide range of influential articles and (2) identify the "citation classics" and milestone articles related to the meniscus of the knee. The Science Citation Index Expanded subsection of the Web of Science Core Collection was systematically searched for the 50 most cited meniscus articles. Data pertaining to bibliometric and publication characteristics were extracted and reported using descriptive statistics. The top 50 articles were published between the years 1941 and 2014 and collectively cited 13,152 times. The median (interquartile [IQR]) number of total citations per article was 203.5 (167.0-261.8), while the median citation rate was 9.6 (7.4-13.9) citations per year. The most cited article was "Knee joint changes after meniscectomy," published in 1948. The article with the highest citation rate of 78.4 citations per year was "The long-term consequence of anterior cruciate ligaments and meniscus injuries - osteoarthritis," published in 2007. The majority of articles were clinical outcome studies (n = 28, 56%). The top 50 most cited meniscus articles represent a compilation of highly influential articles which may augment reading curriculums and provide a strong knowledge base for orthopaedic surgery residents and fellows. The decade with the most articles was the 2000s, representing a recent acceleration in meniscus-based research. This is a level IV, cross-sectional study.

The Altmetric Attention Score Is Associated With Citation Rates and May Reflect Academic Impact in the Total Joint Arthroplasty Literature

Background: Given the increasing interest and potential use of social media for the promotion of orthopedic literature, there is a need to better understand Altmetrics. Purposes: We sought to determine the relationship between the Altmetric Attention Score (AAS) and the number of citations for articles on total joint arthroplasty (TJA) published in orthopedics journals. We also sought to determine the predictors of greater social media attention for these articles. Methods: Articles on TJA published in Bone and Joint Journal (BJJ), Journal of Bone and Joint Surgery (JBJS), Clinical Orthopedics and Related Research (CORR), Journal of Arthroplasty, Journal of Knee Surgery, Hip International, and Acta Orthopaedica in 2016 were extracted (n = 498). One-way analysis of variance with Bonferroni corrections was used to compare AAS and citations across journals. Multivariate regressions were used to determine predictors of social media attention and number of citations. Results: The mean AAS and number of citations were 7.5 (range: 0-289) and 16.7 (range: 0-156), respectively. Significant between-group effects were observed according to journal for AAS and number of citations. Publishing an article in JBJS was the strongest predictor of higher number of citations. Publishing an article in BJJ was the only independent predictor of higher AAS, while publishing an article in JBJS or CORR trended toward statistical significance. A higher AAS was a significant predictor of a higher number of citations. Number of citations and number of study references were positive predictors of greater social media attention on Twitter and Facebook. Conclusions: In articles on TJA published in 7 journals in 2016, a higher AAS was a associated with a higher number of citations. Various bibliometric characteristics were found to be significantly associated with greater social media attention; the most common influences were number of citations and number of references. Researchers in orthopedics can use this information when considering how to assess the impact of their work.

Twitter Use Among Orthopedic Surgery Journals Correlates With Increased Citation Rates

Use of alternative online means of distribution for research is a rapidly evolving area in orthopedics. In this study, we investigate the impact of Twitter on research citation rates and the association between Altmetric Attention Score (AAS) and citation rates across major orthopedic journals. Original research articles published in a selection of 10 journals between January 2018 and December 2018 were analyzed for number and source of tweets, AAS, and number of citations. We determined the relationship between Twitter use of different sources and number of citations across all journals and within each individual journal, any statistical differences in citations and AAS for tweeted vs nontweeted articles, and the correlation between journal impact factor and average number of monthly tweets. We included 2916 articles in our study, at an average of 26 months after publication. The mean AAS was 9.7 (SD, 45.1; range, 0-1125), and mean citation rate was 6.4 (SD, 8.5; range, 0-166). Impact factor was strongly correlated with average monthly tweets (r²=0.77). Tweeted articles received 8.51 citations on average, compared with 2.56 citations for nontweeted articles (P<.05). Tweets sent by the author/department had the highest impact on future citations (P<.01). Tweets by news outlets had a smaller, positive effect on citations (P<.01). Tweets sent by Arthroscopy (P<.01) and Journal of Pediatric Orthopaedics (P<.01) had high impacts compared with other journals. [Orthopedics. 2023;46(1):e38-e44.].

The fifty most cited publications in shoulder arthroplasty research

Introduction

Frequency of citation provides one quantitative metric of the impact that an article has on a given field. The purpose of this study was to evaluate characteristics of the 50 most cited publications on shoulder arthroplasty.

Methods

The Web of Science database was used to determine the 50 most frequently cited shoulder arthroplasty articles. Articles were evaluated for several factors including type of arthroplasty, citation frequency and rate, source journal, country of origin, study type, and level of evidence.

Results

The most common countries of origin were the United States (60%) followed by France (24%) and Switzerland (6%). A total of 27 (54%) articles included anatomic total shoulder arthroplasty (TSA), 18 (36%) included reverse total shoulder arthroplasty (RTSA), and 15 (30%) included hemiarthroplasty. Articles including RTSA had the greatest number of citations compared to those on TSA (p = 0.037) and hemiarthroplasty (p = 0.035). Citations per year were also greatest with RTSA compared to TSA and hemiarthroplasty (p ≤ 0.001).

Discussion

This citation analysis includes many of the landmark studies that shaped, and continue to impact, the field of shoulder arthroplasty. This list provides a group of influential articles that provide a foundation for future research in shoulder arthroplasty.

How Does Open Access Publication Impact Readership and Citation Rates of Lumbar Spine Literature?

STUDY DESIGN

This was a retrospective review.

OBJECTIVE

The objective of this study was to assess the impact of open access (OA) publication on citation rates and attention scores of literature related to lumbar spine surgery.

SUMMARY OF BACKGROUND DATA

OA literature allows readers to view full-text manuscripts of research publications free of charge, however, OA publication is often associated with substantial fees for authors.

METHODS

The Altmetric database was searched for articles related to lumbar spine surgery. Title, journal, publication date, Dimensions Citations, Mendeley Readers, Altmetric Attention Score (AAS), number of public mentions, and OA status were collected for each included article. The influence of OA status on Dimensions Citations, Mendeley Readers, and each individual component of the AAS was assessed. To control for journal influence, impact of OA on Dimensions Citations and AAS was separately assessed for each of the top 10 journals contributing the most mentioned articles. The top 25 most cited articles and top 25 articles by AAS were also characterized.

RESULTS

A total of 5245 articles were included, of which 2063 were published with OA and 3182 were not. OA status was a significant, independent predictor of AAS and Mendeley Readers (both P <0.001), but not Dimensions Citations ( P =0.422). OA status significantly predicted mentions in news stories ( P =0.003), Twitter posts ( P <0.001), Facebook posts ( P <0.001), and Wikipedia citations ( P =0.011). Of the top 10 contributing journals, OA status significantly predicted Dimensions Citations for European Spine Journal , Journal of Neurosurgery: Spine , and Neurosurgery ( P ≤0.005) and predicted AAS for Spine , European Spine Journal , The Spine Journal , Journal of Neurosurgery: Spine , and Neurosurgery ( P ≤0.017, all).

DISCUSSION

OA status appeared to significantly impact public attention scores, but not citation rates, although these effects did vary based on the journal in which articles were published. Authors may want to consider OA publication based on their target audience and the goal of their research.

Institution Origin and Medical School Rank Impact the Citation Frequency and Publication Rate in Orthopaedic Sports Medicine Journals

Purpose

To examine the trends between various categories of institutions with their respective published orthopaedic sports medicine content and to determine the publication output and citation rate from the 25 highest-ranked medical schools compared with lower-ranked institutions.

Methods

Publications between 2015 and 2019 from the American Journal of Sports Medicine, Journal of Bone and Joint Surgery, Journal of Shoulder and Elbow Surgery, Clinical Orthopaedics and Related Research, and Arthroscopy were categorized into university/university affiliated hospitals, non-university affiliated teaching hospitals, public/semi-government research institutes, nonprofit research institutes, private sector institutions, government institutions, and other institutions. Citation rates were collected from PubMed for the first and corresponding author. Similarly, corresponding authors were stratified by U.S. News and World Report 2021 medical school research rankings.

Results

Of the 12,152 publications identified, 5,044 publications met the inclusion criteria. Nonprofit research institutions garnered the greatest number of citations on average (6.44 based on first author, SD 8.83, n = 214; 6.62 based on corresponding author, SD 9.65, n = 208; P < .001), while university/university-affiliated hospitals produced the majority of published articles (77.0% based on first author, 76.8% based on corresponding author), but had lower average citation rates (4.48 based on first author, SD 6.67, n = 3,886; 4.44 based on corresponding author, SD 6.55, n = 3,873; P < .001). Furthermore, of 1953 medical school publications, the top 25 accounted for 53.1% of publications; however, there was no statistical difference between their citation rates and those of lower rankings (P = 0.47).

Conclusions

Publications are cited at different rates, depending on their institution of origin. In addition, high-ranking medical schools produce a disproportionately greater output of publications than lower-ranking schools, but there is no statistically significant difference in citation rates on an individual publication basis.

Clinical Relevance

Knowing how an institution’s ranking influences publication and citation rates can help us understand bias in the scientific literature.

Analysis of Eastern Asia’s Contributions to Major Orthopaedic Journals in the Past 21 Years

Introduction

Over the past two decades, Asia has experienced the rise and integration of Western medicine and digital health in its field of medicine. In this study, we investigated the trends in orthopaedic publications from three Asian countries: China, Japan, and Korea.

Methods

PubMed was used to measure the number of publications from China, Japan, and Korea in the past 21 years, from 1998 to 2020. The average percentage change in publications during this 21-year time period was analyzed using descriptive statistics. The average annual change in the number of publications from each country was also determined. One-way analysis of variance and two-group t-tests were utilized for statistical analyses with a p-value of <0.05 as the cut-off value for statistical significance.

Results

From years 1998 to 2020, there was a mean 35.5% ± 70.7% annual increase in the number of total publications from China, in comparison to a 5.1% ± 14.0% annual increase from Japan (p = 0.005) and a 27.3% ± 40.0% annual increase from Korea (p = 0.586).

Conclusion

For the past two decades, there has been a strong positive trend regarding the total number of orthopaedic publications from China. This finding might be related in part to an increased integration of Western medicine and the use of digital medicine, which followed a similar trend during the time period we analyzed. Korea and Japan also exhibited a positive trend in orthopaedic publications, which may be indicative of an improving educational system and greater general support for research.

Predictors of Above Average 6-Year Citation Rates in Leading Spine-Specific Medical Journals

STUDY DESIGN

Cross-sectional.

OBJECTIVE

To identify predictors of manuscripts achieving 6-year citation rates higher than the mean in spine-specific literature.

SUMMARY OF BACKGROUND DATA

An article's citation rate demonstrates its contribution to academia and its quality. Predictors of citation rates have not yet been studied in spine-specific medical literature.

METHODS

Three leading spine-specific journals were identified by a weighted scoring system comparing various journal metrics. Research articles published in 2014 were evaluated from the following journals: Spine, European Spine Journal, and Journal of Neurosurgery: Spine. Article features analyzed included journal of origin, number of words in article title, author count, degree of first author, conflicts of interest, quantity of contributing academic institutions, country of origin, study topic, study design, level of evidence, sample size, reference count, and citation rate. Multivariate logistic regression was used to determine predictors of above average citation rate at 6 years following publication.

RESULTS

The final analysis included 1091 articles. Spine had a significantly higher citation rate than European Spine Journal (P = 0.0008); however, no significant differences were observed between Spine and Journal of Neurosurgery: Spine. Regression analysis demonstrated that studies originating in North America (OR:1.44, 95% CI:1.01-2.01, P = 0.04), those with 6 ≥ authors (OR:1.72, 95% CI:1.29-2.30, P < 0.001), sample size >100 (P < 0.001), prospective case series (OR: 2.67, 95% CI: 1.24-5.76), and retrospective case series (OR: 1.99, 95% CI: 1.07-3.73) were independent predictors of achieving above average 6-year citation rates.

CONCLUSION

Spine, European Spine Journal, and Journal of Neurosurgery: Spine had the highest 6-year citation rates of the top 10 orthopedic spine journals, with Spine being significantly higher than European Spine Journal. Studies originating in North America, those with six or more authors, sample sizes > 100, and those that are retrospective or prospective case series are independent predictors of greater citation rates at 6 years in orthopedic spine-specific medical literature.Level of Evidence: 4.

Infographics Are More Effective at Increasing Social Media Attention in Comparison With Original Research Articles: An Altmetrics-Based Analysis

PURPOSE

To compare social media attention and citation rates between infographics (visual abstracts) and original research articles.

METHODS

All infographics in 2019 from electronic versions of Arthroscopy were matched by topic to articles in the "Original Research" section of the journal in a 4:1 ratio within the same year. The primary outcome was the Altmetric Attention Score (AAS), a cumulative measure of social media attention from various platforms such as Twitter and Facebook. Secondary outcomes included citation rates, article characteristics, and number of shares on social media platforms. Independent t tests and χ² analyses were used to compare primary and secondary outcomes between infographics and control articles. Multivariate linear regression analysis was performed to determine the association between article type and social media attention while controlling for bibliometric characteristics.

RESULTS

A total of 60 matched research articles (n = 48, 80.0%) and infographics (n = 12, 20.0%) published in 2019 in Arthroscopy were included. The mean AAS among all infographics was 29.75 ± 32.84 (range, 3-118), whereas the mean AAS among all control research articles was 5.75 ± 8.90 (range, 0-41), representing a statistically significant difference (P < .001). Infographics had significantly more Twitter mentions (100% vs 70.8%, P < .001) and Facebook mentions (75% vs. 6.2%, P < .001) compared with original articles. Multivariate linear regression analysis demonstrated a statistically significant and positive association between AAS and article type, with an additional mean increase in the AAS of 33.7 (95% confidence interval 11.6-50.6; P = .003) for every infographic article compared with an original research article. The mean citation rate among all infographics was 2.4 ± 2.4 (range, 0-7), whereas the mean citation rate among all control research articles was 2.2 ± 4.0 (range, 0-27), which was not a significant difference (P = .69).

CONCLUSIONS

Infographics resulted in significantly greater AAS and social media attention in comparison with original research articles of similar topics. We recommend the routine creation of infographics by journals to increase the social media attention that their research and chosen topics of interest receive. However, viewers of infographics should read them out of interest but turn their attention toward the original article or a source of more detailed information before making changes in clinical decision-making or practice, as they can be oversimplified.

CLINICAL RELEVANCE

Infographics are an increasingly used by journals as a form of depicting research findings from select studies. By producing infographics, journals may increase the amount of social media attention received for a particular study or topic of interest.

Orthopaedic Randomized Controlled Trials Published in General Medical Journals Are Associated With Higher Altmetric Attention Scores and Social Media Attention Than Nonorthopaedic Randomized Controlled Trials

PURPOSE

To (1) compare the Altmetric Attention Score (AAS) and citation rates between orthopaedic and nonorthopaedic randomized controlled trials (RCTs) from 5 high-impact medical journals and (2) identify general characteristics of these articles associated with greater exposure on social media platforms.

METHODS

Articles published in The New England Journal of Medicine (NEJM), Lancet, The Journal of the American Medical Association (JAMA), Annals of Internal Medicine, and Archives of Internal Medicine between January 2011 and December 2016 were analyzed. These journals were selected based on retaining high impact factors with rigorous publication standards and availability of the AAS for their publications. The queried time frame was chosen to balance the inception of the AAS with an optimal period for citation accrual. A total of 14 article characteristics, in addition to number of Tweets, Facebook shares, news mentions, and the AAS, were extracted. Inclusion criteria were orthopaedic RCTs reporting on outcomes after surgical intervention. Linear regression was used to assess the relationship between publication characteristics and the AAS and social media attention.

RESULTS

A total of 9 orthopaedic and 59 nonorthopaedic RCTs were included. The mean AASs were significantly different (574 ± 565.7 versus 256.9 ± 222.3, P = .003), whereas citation rate was not (192.2 ± 117.1 versus 382.3 ± 560.3, P = .317). Orthopaedic RCTs had a significantly greater number of mentions on Twitter and Facebook (P < .001). A higher AAS significantly associated with a greater number of citations (β = 0.75, P = .019) for orthopaedic RCTs. The mean AAS of orthopaedic RCTs favoring nonoperative management (809.6 ± 676.3) was greater than those favoring operative treatment (292.0 ± 248.9) but was not statistically significant (P = .361).

CONCLUSION

Orthopaedic RCTs published in 5 high-impact general medical journals had a significantly greater mean AAS relative to nonorthopaedic RCTs, with no differences in citation rates. Additionally, there was a strong association between the AAS and citation rate of orthopaedic RCTs. Orthopaedic RCTs had greater social media exposure on both Twitter and Facebook.

CLINICAL RELEVANCE

Orthopaedic surgeons, researchers, and providers who publish RCTs in high-impact medical journals can anticipate extensive social media attention for their articles relative to other nonorthopaedic RCTs in the same journals. Social media attention may be related to operative versus nonoperative management topics. This study provides further evidence for the increasing use of the AAS and its association with citation accrual.

Altmetrics Attention Scores for Randomized Controlled Trials in Total Joint Arthroplasty Are Reflective of High Scientific Quality: An Altmetrics-Based Methodological Quality and Bias Analysis

The Altmetric Attention Score (AAS) has been associated with citation rates across medical and surgical disciplines. However, factors that drive high AAS remain poorly understood and there remains multiple pitfalls to correlating these metrics alone with the quality of a study. The purpose of the current study was to determine the relationship between methodologic and study biases and the AAS in randomized controlled trials (RCTs) published in total joint arthroplasty journals.

What Is the Predictive Ability and Academic Impact of the Altmetrics Score and Social Media Attention?

BACKGROUND

Citation rate and journal impact factor have traditionally been used to assess research impact; however, these may fail to represent impact beyond the sphere of academics. Given that social media is now used to disseminate research, alternative web-based metrics (altmetrics) were recently developed to better understand research impact on social media. However, the relationship between altmetrics and traditional bibliometrics in orthopaedic literature is poorly understood.

PURPOSE

To (1) assess the extent that altmetrics correlate with traditional bibliometrics and (2) identify publication characteristics that predict greater altmetrics scores.

STUDY DESIGN

Cross-sectional study.

METHODS

Articles published in The American Journal of Sports Medicine (AJSM), The Journal of Bone and Joint Surgery, Clinical Orthopaedics and Related Research, Acta Orthopaedica, and Knee Surgery, Sports Traumatology, Arthroscopy between January 2016 and December 2016 were analyzed. Among the extracted publication characteristics were journal, number of authors, geographic region of origin, highest degree of first author, study subject and design, sample size, conflicts of interest, and level of evidence; number of references, institutions, citations, tweets, Facebook mentions, and news mentions; and Altmetric Attention Score (AAS). Multivariate regressions were used to determine (1) publication characteristics predictive of AAS and social media attention (mentions on Twitter, Facebook, and the news) and (2) the relationship between AAS and citation rate.

RESULTS

A total of 496 published articles were included, with a mean AAS of 8.6 (SD, 31.7; range, 0-501) and a mean citation rate of 15.0 (SD, 16.1; range, 0-178). Articles in AJSM (β = 19.9; P < .001), publications from North America (β = 8.5; P = .033), and studies concerning measure validation/reliability (β = 25.5; P = .004) were independently associated with higher AAS. Greater AAS score significantly predicted a greater citation rate (β = 0.16; P < .0001). The citation rate was an independent predictor of greater social media attention on Twitter, Facebook, and the news (odds ratio range, 1.02-1.03; P < .05 all).

CONCLUSION

AAS had a significant positive association with citation rates of articles in 5 high-impact orthopaedic journals. Articles in AJSM, studies concerning measure validation and reliability, and publications from North America were positively associated with greater AAS. A greater number of citations was consistently associated with publication attention received on social media platforms.

The top 100 most-cited Orthopaedics & Traumatology: Surgery & Research articles

BACKGROUND

The French peer-reviewed journal Revue d'Orthopédie founded on 1st January 1890 extended its scope in 2009 by creating the English-language, online-only, indexed journal Orthopaedics & Traumatology: Surgery & Research (OTSR). Bibliometric data help authors and readers assess the citation potential of articles published in a given journal. We found no bibliometrics for the first 10years of OTSR. The objectives of this bibliometric study were to identify (i) the 100 most-cited OTSR articles and (ii) the specialties or article types most often involved in citations.

METHODS

The Scopus database was used to determine the citation rates of the 2158 articles published in OTSR during the journal's first 10years. A bibliometric analysis was performed on the 100 most-cited articles.

RESULTS

Mean time since publication of the 100 most-cited articles was 6.60±1.66years (range: 2-10years) and mean number of citations per article was 49.59±24.16 (range: 30-169). Mean number of citations per year was 7.75±3.26 (range: 4-18.78) and mean number per author was 5.52±3.14 (range: 1-21). The first author was French in 89/100 cases. Of the 100 articles, 56 were based on a multi-centre study and 21 on an international study. Finally, 22/100 articles reported studies sponsored by a scientific society.

DISCUSSION

The 100 articles identified in this study deserve to be viewed as influential. The number of citations will continue to rise, thereby amplifying the impact of OTSR on worldwide research in orthopaedic surgery.

LEVEL OF EVIDENCE

IV, systematic retrospective analysis.