Level of evidence and conflict of interest disclosure associated with higher citation rates in orthopedics

Characteristics and Methodological Quality of the Top 50 Most Influential Articles on Stroke Rehabilitation: A Bibliometric Analysis

ABSTRACT

This study aimed to conduct a comprehensive review of the top 50 most influential articles on stroke rehabilitation to investigate characteristics, such as the number of citations, year of publication, study design, and research topic, as well as to assess the evidence level and methodological quality. Moreover, we performed a supplementary assessment of the top 10 articles published within the past 5 yrs in the same domain, aiming to discern potential shifts in trends and methodological quality. Web of Science was used to search for articles on stroke rehabilitation. The data extracted from the articles included title, journal impact factor, year of publication, total number of citations, article topic, study design, and others. The level of evidence and methodological quality were assessed by two reviewers. Noninvasive brain stimulation and robotic rehabilitation were frequently discussed in the top 50 articles. We found that there was no difference in methodology quality between the top 50 articles in all years and the top ten articles in the past 5 yrs. Furthermore, the number of citations and citation density were not associated with the methodological quality. The findings suggest that the number of citations alone may not be a reliable indicator of research quality.

The impact of surgical randomised controlled trials on the management of FAI syndrome: a citation analysis

PURPOSE

To identify and assess the clinical impact of randomised controlled trials (RCTs) assessing the surgical management of femoroacetabular impingement syndrome (FAIS) through a citation analysis.

METHODS

MEDLINE, EMBASE and CENTRAL were searched from inception to April 22, 2023 for RCTs assessing the surgical management of FAIS. Study characteristics were directly abstracted from included trials and citation metrics were obtained from the Clarivate Web of Knowledge database on May 19, 2023. The continuous fragility index (CFI) was calculated for eligible outcomes. Univariate regression models were used to explore correlations between total citations per year and various study characteristics.

RESULTS

Ten studies comprising one thousand two hundred ninetypatients were eligible for analysis. Studies were published from 2013 to 2023. Eight countries were represented across various trials with 91% being either North American or European. The mean journal impact factor of published studies was 39.684 (median 2.982; range 1.31-202.73). The mean citation density was 14.17 (range 0.33-48.67). The median CFI was 4.8 (range 1-32.2). Correlation analysis demonstrated strong and statistically significant correlations to study sample size (R = 0.75, p = 0.012), journal impact factor (R = 0.80, p = 0.006) and continuous fragility index (R = 0.95, p = 0.015).

CONCLUSION

Trials assessing the surgical management of FAIS present with a wide range of clinical uptake based on citation density and are published in journals of broadly variable impact factor. Despite promising citation metrics, high-quality evidence on arthroscopy for FAIS is limited to the United States and Europe with an unclear international impact. Future knowledge translation efforts are warranted to maximise the international uptake of evidence regarding arthroscopic management of FAIS.

LEVEL OF EVIDENCE

I.

Funding has no effect on clinical outcomes of total joint arthroplasty emerging technologies: a systematic review of bibliometrics and conflicts of interest

Background

The use of new total joint arthroplasty technologies, including patient-specific implants/instrumentation (PSI), computer-assisted (CA), and robotic-assisted (RA) techniques, is increasing. There is an ongoing debate regarding the value provided and potential concerns about conflicts of interest (COI).

Methods

PRISMA guidelines were followed. PubMed, MEDLINE, and Web of Science databases were searched for total hip and knee arthroplasties, unicompartmental knee arthroplasties (UKA), PSI, CA, and RA. Bibliometric data, financial COI, clinical/functional scores, and patient-reported outcomes were assessed.

Results

Eighty-seven studies were evaluated, with 35 (40.2%) including at least one author reporting COI, and 13 (14.9%) disclosing industry funding. COI and industry funding had no significant effects on outcomes (P = 0.682, P = 0.447), and there were no significant effects of conflicts or funding on level of evidence (P = 0.508, P = 0.826). Studies in which author(s) disclosed COI had significantly higher relative citation ratio (RCR) and impact factor (IF) than those without (P < 0.001, P = 0.032). Subanalysis demonstrated RA and PSI studies were more likely to report COI or industry funding (P = 0.045). RA (OR = 6.31, 95% CI: 1.61–24.68) and UKA (OR = 9.14, 95% CI: 1.43–58.53) had higher odds of reporting favorable outcomes than PSI.

Conclusions

Author COIs (about 40%) may be lower than previously reported in orthopedic technologies/techniques reviews. Studies utilizing RA and PSI were more likely to report COI, while RA and UKA studies were more likely to report favorable outcomes than PSI. No statistically significant association between the presence of COIs and/or industry funding and the frequency of favorable outcomes or study level of evidence was found.

Level of evidence

Level V Systematic Review

Supplementary Information

The online version contains supplementary material available at 10.1186/s42836-022-00146-3.

The most influential studies concerning revision shoulder arthroplasty research

Background

Bibliometric analysis is a unique tool that can be used to study the characteristics and trends of a given topic. This study aimed to report on the most influential studies concerning revision shoulder arthroplasty research.

Methods

On July 4th, 2022, the Institute of Scientific Information (ISI) Web of Knowledge Database was used to identify articles concerning revision shoulder arthroplasty research. The top 50 most cited articles were selected and analyzed.

Results

The mean number of citations was 142 (median: 97; range 599-70). Most articles were published in the 2010s (56%), followed by the 2000s (38%), and 1990s (6%). The most common level of evidence (LOE) was LOE II (42%) followed by LOE IV (38%), LOE I and III each had 10%. The greatest number of papers were published in the Journal of Shoulder and Elbow Surgery (46%), followed by the Journal of Bone and Joint Surgery- American Version (14%).

Conclusion

This review can serve as a useful tool to study the most influential articles concerning revision shoulder arthroplasty research. Most of the articles were classified as clinical outcomes (62%), followed by natural history/epidemiology (12%), and surgical technique (10%). Our findings suggest that high-quality studies (LOE I) are lacking and other areas of research besides clinical outcomes are not as well studied.

Open Access Articles Garner Increased Social Media Attention and Citation Rates Compared With Subscription Access Research Articles: An Altmetrics-Based Analysis

BACKGROUND

To better understand the research impact on social media, alternative web-based metrics (Altmetrics) were developed. Open access (OA) publishing, which allows for widespread distribution of scientific content, has become increasingly common in the medical literature. However, the relationship between OA publishing and social media impact remains unclear.

PURPOSE

To compare social media attention and citation rates between OA and subscription access (SA) research articles within the orthopaedic and sports medicine literature.

STUDY DESIGN

Cross-sectional study.

METHODS

Articles published as either OA or SA in 5 high-impact hybrid orthopaedic journals between January 2019 and December 2019 were analyzed. The primary outcome was the Altmetric Attention Score (AAS), a validated measure of social media attention. Secondary outcomes included citation rates, article characteristics, and the number of shares on social media. Independent t tests and chi-square analyses were used to compare outcomes between OA and SA articles. A multivariable linear regression analysis was performed to determine the association between article type and AAS while controlling for bibliometric characteristics.

RESULTS

A total of 2143 articles (246 OA articles, 11.5%; 1897 SA articles, 88.5%) were included. The mean AAS among all OA articles was 62.4 ± 184.6 (range, 0-2032), whereas the mean AAS among all SA articles was 18.4 ± 109.8 (range, 0-3425), representing a statistically significant difference (P < .001). The mean citation rate among OA articles was significantly higher (17.0 ± 22.5; range, 0-139) than that of SA articles (8.6 ± 13.4; range, 0-169) (P < .001). Multivariable linear regression analysis demonstrated that OA status (β = 15.15; P = .044), number of institutions (β = 2.13; P = .023), studies classified as epidemiological investigations (β = 107.40; P < .001), and disclosure of a conflict of interest (β = -11.18; P = .032) were significantly associated with a higher AAS.

CONCLUSION

OA articles resulted in significantly greater AAS and citations in comparison with SA articles. Articles published through the OA option in hybrid journals as well as those with a higher number of institutions, those that disclosed a conflict of interest, and those classified as epidemiological investigations were positively associated with greater AAS in addition to a greater number of citations. The potential for more extensive research dissemination inherent in the OA option may therefore translate into greater reach and social media attention.

Self-Reported Conflicts of Interests and Financial Disclosures in The Journal of Foot & Ankle Surgery: A Systematic Review

Industry, academia, and professional societies provide financial and in-kind support for physician-lead research; however, the prevalence and role remain unreported. From consultancies to leadership positions, foot and ankle surgeons receive a spectrum of support. To provide transparency between these relationships and published outcomes, journals report conflicts of interest (COI) and financial disclosures (FD). This investigation analyzes self-reported COIs and FDs in The Journal of Foot & Ankle Surgery (JFAS)®. A systematic review of manuscripts reporting COIs and FDs from the January 2008 through November 2020 issues of JFAS was conducted. Editorials, commentaries, and technique articles were excluded. Disclosure type, level of evidence, and affiliated country of authorship were collected. Trends and proportions of articles with disclosures were analyzed from before a published Open Payments Database (OPD) (2008-2013) through 2020. Among 2699 articles, 382 reported a COI or FD. The number of manuscripts with COIs and FDs increased since 2008 (p < .001). The proportion of articles with COIs or FDs was greater after the OPD was published compared to prior (p < .001). Overall, 86.35% of reported COIs were industry related while 37.09% of FDs were hospital, university, or state sponsor affiliated. International authorship was a negative predictor of COIs and FDs (p < .001). Level 3 and 4 studies were 4.60 (95%CI [0.85-24.85]) and 5.56 (95%CI [1.04-29.72]) times as likely to have self-reported a COI compared to level 1 studies, respectively. Level 2 and 5 studies were 0.33 (95%CI [0.04-3.16]) and 0.36 (95%CI [0.04-3.13]) times as likely to have self-reported a FD compared to level 1 studies, respectively. This investigation found an increase in the proportion of manuscripts with self-reported COIs and FDs since first documented in JFAS. These findings illustrate the ubiquity of author industry involvement, though future studies may examine the relevancy of these roles to published research.

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.

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.

Predictors of Citations in Neurosurgical Research: A 5-Year Follow-Up

BACKGROUND

Citation rates are an important measure for the impact of articles. This study is the most comprehensive analysis of predictors for scientific neurosurgical research articles.

METHODS

Scientific articles published in 13 neurosurgical journals in 2015 were selected. Data collected included article subject, level of evidence (LOE), journal impact factor (IF), authorship, contributing centers, and study design. Citation counts were collected for each article in Web of Science (WoS) and Google Scholar (GS) 2.5 and 5 years after publication and Scopus 5 years after publication. A generalized linear mixed-effects model using the predictors of search engine, LOE, number of centers, number of authors, and IF was constructed to predict total citation count at 5 years.

RESULTS

A total of 2867 articles generated 39,190 citations in WoS, 61,682 in GS, and 43,481 in Scopus. The median number of citations per article was 10 (interquartile range [IQR], 14) in WoS, 15 (IQR, 20) in GS, and 11 (IQR, 15) in Scopus. On average, for every 1 citation in WoS, Scopus and GS identified 1.11 and 1.58 citations, respectively. Significant predictors of citation count in all databases 5 years after publication included search engine, LOE, number of centers, number of authors, number of countries, journal IF, and the month of publication (P < 0.05). The article subject (e.g., tumor or spine) did not significantly predict citation counts.

CONCLUSIONS

In the most thorough analysis of citation predictors in the neurosurgical literature, search engine, LOE, number of centers, number of authors, number of countries, journal impact factor, and month of publication influenced citations 5 years after publication.

Cost-effectiveness analyses in shoulder arthroplasty: a critical review using the Quality of Health Economic Studies (QHES) instrument

HYPOTHESIS

The purpose of this study was to perform a systematic review to identify cost-analysis studies pertaining to shoulder arthroplasty, provide a comprehensive review of published studies, and critically evaluate the quality of the available literature using the Quality of Health Economic Studies (QHES) instrument.

METHODS

A systematic review of the literature was performed to identify cost analyses examining shoulder arthroplasty. The inclusion criteria included studies pertaining to either shoulder hemiarthroplasty (HA), total shoulder arthroplasty (TSA), or reverse TSA. Articles were excluded based on the following: nonoperative studies, nonclinical studies, studies not based in the United States, and studies in which no cost analysis was performed. The quality of studies was assessed using the QHES instrument. One-sided Fisher exact testing was performed to identify predictors of both low-quality (ie, QHES score < 25th percentile) and high-quality (ie, QHES score > 75th percentile) cost analyses based on items within the QHES checklist.

RESULTS

Of the 196 studies screened, 9 were included. Seven studies conducted cost analyses comparing reverse TSA vs. arthroscopic rotator cuff repair, HA, or total hip arthroplasty, and 2 studies examined TSA vs. HA for primary glenohumeral arthritis. The average QHES score among all studies was 86.22 ± 13.39 points. Failure to include an annual cost discounting rate was associated with a low-quality QHES score (P = .03). In addition, including a discussion of the magnitude and direction of potential biases was associated with a high-quality score (P = .03).

CONCLUSIONS

Shoulder arthroplasty is a cost-effective procedure when used to treat a multitude of shoulder pathologies. The overall quality of cost analysis in shoulder arthroplasty is relatively good, with an average QHES score of 86.22 points. Studies failing to include an annual cost discounting rate are more likely to score below the 25th percentile, whereas those including a discussion of the magnitude and direction of potential biases are more likely to achieve a score in excess of the 75th percentile.

Study Characteristics Related to Citation Rates in Hip & Pelvis: An Analysis of Articles Published between 2009 and 2019

Purpose

We classified the articles published in the journal Hip & Pelvis and analyzed the relationship between study characteristics and citation rates.

Materials and Methods

All articles published in Hip & Pelvis from 2009 to 2019 were included. We classified the articles according to the type, language, listing in PubMed Central (PMC), treatment modality, material, design, anatomical focus, number of authors, and number of cases. We analyzed the citation rate according to this classification, with yearly citation rate reflecting the exposure period until March 2020.

Results

The yearly citation rate increased significantly after the language of the journal was changed from Korean to English in June 2014 (mean=0.96 vs. 1.63, P<0.05), and again after the journal was listed in PMC in March 2016 (mean=1.05 vs. 1.92, P<0.05). The yearly citation rates of review articles was highest, followed by those of editorials, original articles, and case reports (in this order). Among original articles, trauma-related articles had higher yearly citation rates than non-trauma-related articles (mean=1.00 vs. 0.68, P=0.034). Among clinical articles, studies focusing on the pelvis had higher yearly citation rates than studies on the hip or femur (mean=1.85 vs. 0.71 vs. 0.91, P=0.003).

Conclusion

The yearly citation rate of articles increased significantly after the language of Hip & Pelvis was changed to English and after the journal was listed in PMC. The mean yearly citation rate of articles focusing on the pelvis was significantly higher than that of articles focusing on the hip or femur.

Do successful PhD outcomes reflect the research environment rather than academic ability?

Maximising research productivity is a major focus for universities world-wide. Graduate research programs are an important driver of research outputs. Choosing students with the greatest likelihood of success is considered a key part of improving research outcomes. There has been little empirical investigation of what factors drive the outcomes from a student's PhD and whether ranking procedures are effective in student selection. Here we show that, the research environment had a decisive influence: students who conducted research in one of the University's priority research areas and who had experienced, research-intensive, supervisors had significantly better outcomes from their PhD in terms of number of manuscripts published, citations, average impact factor of journals published in, and reduced attrition rates. In contrast, students’ previous academic outcomes and research training was unrelated to outcomes. Furthermore, students who received a scholarship to support their studies generated significantly more publications in higher impact journals, their work was cited more often and they were less likely to withdraw from their PhD. The findings suggest that experienced supervisors researching in a priority research area facilitate PhD student productivity. The findings question the utility of assigning PhD scholarships solely on the basis of student academic merit, once minimum entry requirements are met. Given that citations, publication numbers and publications in higher ranked journals drive university rankings, and that publications from PhD student contribute approximately one-third of all research outputs from universities, strengthening research infrastructure and supervision teams may be more important considerations for maximising the contribution of PhD students to a university’s international standing.

Trends in the level of evidence and impact of clinical studies published in leading oral implantology journals: 2008-2018

OBJECTIVES

To present the characteristics and level of evidence (LOE) of clinical studies published in leading oral implantology journals during 2008-2018 and to explore whether the LOE of a study is associated with its scientific and social impact.

MATERIALS AND METHODS

Clinical studies with direct relevance to the evaluation of healthcare interventions published in 2008, 2013, and 2018 in six oral implantology journals were identified via hand searches. A modified 4-level Oxford 2011 LOE tool was used to assess the LOE of all eligible studies. The citation count and Altmetric Attention Score (AAS) of each study were extracted from Web of Science and Altmetric Explorer, respectively. Thereafter, multivariable generalized estimation equation analyses were used to investigate the association between LOE, citation counts, and AAS, adjusting for potential confounding factors and clustering effects.

RESULTS

A total of 763 clinical studies were included, among which the proportion of level-1, level-2, level-3, and level-4 studies was 2.4%, 30.4%, 40.2%, and 27.0%, respectively. During 2008-2018, the proportion of high LOE studies (level-1 and level-2) increased substantially from 24.6% to 43.1%, although the number of systematic reviews that only include randomized controlled trials has remained limited. According to multivariable analyses, the citation count (p = .002) and AAS (p = .005) of high LOE studies were both significantly greater than those of low LOE studies.

CONCLUSIONS

During the past decade, the proportion of high LOE studies has increased substantially in the field of oral implantology. Clinical studies with higher LOE tend to have greater scientific and social impact.

The level of evidence, scientific impact and social impact of clinical studies in periodontology: A methodological study

AIMS

To analyse the level of evidence (LOE) of clinical studies in the field of periodontology, and to investigate whether LOE is a predictor of scientific impact and social impact.

MATERIALS AND METHODS

Clinical studies published in five leading periodontal journals during 2015-2019 were identified. The LOE of included studies were assessed with a modified LOE classification system based on Oxford 2009 LOE, Oxford 2011 LOE and GRADE guidelines. Citation counts were harvested from Web of Science and Scopus. Altmetric Attention Scores (AAS) were obtained from Altmetric Explorer. Multivariable generalized estimation equation (GEE) analyses were used to investigate association between LOE and citation count, as well as between LOE and AAS.

RESULTS

Among 768 studies included, the proportion of level-1, level-2, level-3 and level-4 was 10.4%, 44.8%, 13.7% and 31.1%, respectively. In the multivariable GEE analyses, high LOE was a significant predictor of higher average citation count (p = .010) and higher AAS (p < .001).

CONCLUSION

The LOE of clinical studies in the periodontal field is relatively high in general, although it varies significantly in different journals. Studies with high LOE tend to have greater scientific impact and social impact than low LOE studies.

Research methodology used in the 50 most cited articles in the field of pediatrics: types of studies that become citation classics

BACKGROUND

One of the frequently used methods for assessing research trends and the impact of published scientific literature in a particular discipline is citation analysis. Journals may strive to improve their metrics by choosing manuscripts and study designs that are more likely to be cited. The aim of this study was to identify the 50 most-cited articles in the field of pediatrics, analyze their study design and other characteristics of those articles, and assess the prevalence of systematic reviews among them.

METHODS

In December 2017, we searched Web of Science (WoS) for all articles published in the field of pediatrics. Two authors screened articles independently and in the further analysis included 50 articles with the highest number of citations. To avoid bias for scientific papers published earlier, the citation density was calculated. We also analyzed Journal Impact Factor (JIF) of journals where citation classics were published.

RESULTS

The citation density in top 50 cited articles in the field of pediatrics ranged from 33.16 to 432.8, with the average of 119.95. Most of the articles reported clinical science. Median 2016 JIF for journals that published them was 6.226 (range: 2.778 to 72.406). Half of the top 10 highly cited articles in pediatrics were published in a journal with JIF below 5. Most of the studies among the citation classics in pediatrics were cross-sectional studies (N = 22), followed by non-systematic narrative reviews (N = 10), randomized controlled trials (N = 5), cohort studies (N = 5), systematic reviews (N = 2), case-control studies (N = 2), case reports (N = 2), and there was one study protocol and one expert opinion.

CONCLUSION

Few randomized controlled trials and systematic reviews were among citation classics in the field of pediatrics. Articles that use observational research methodology, and are published in journals with lower impact factors, can become citation classics.

Predictors of Citation Rate in the Spine Literature

The number of citations a publication receives has been regarded as one measure of its importance and clinical impact. However, studies have yet to investigate which characteristics are predictors of citation rates within the spine subspecialty literature. To explore this topic, all articles published in 2010 in Spine and from 2010 to 2011 in The Spine Journal and the Journal of Neurosurgery: Spine were reviewed. The Web of Science search engine was used to determine the number of times each article was cited in the 5 years following its publication. Sample characteristics were collected and were compared with a χ test for differences Multivariate logistic regression was utilized to determine if collected study characteristics were associated with achievement of citation frequency higher than the median for the entire study sample. Among the 927 articles analyzed, the 5-year citation number ranged from 0 to 125, with a median of 8 (interquartile range: 4-16). Upon multivariate analysis, the following were identified as predictors of citation number higher than the median: North American origin (P=0.014), sample size >30 (P<0.001), study topic (P<0.050), and publication in the Journal of Neurosurgery: Spine (P<0.001). Practitioners and research personnel can use these findings to help elucidate which factors might affect the potential impact and overall reach of their work in the spine literature.

Assessment of Korea's Orthopedic Research Activities in the Top 15 Orthopedic Journals, 2008-2017

Background

Bibliometrics is increasingly used to assess the quantity and quality of scientific research output in many research fields worldwide. This study aims to update Korea's worldwide research productivity in the field of orthopedics using bibliometric methods and to provide Korean surgeons and researchers with insights into such research.

Methods

Articles published in the top 15 orthopedic journals between 2008 and 2017 were retrieved using the Web of Science. The number of articles, citations and h-index (Hirsch index), funding sources, institutions, and journal patterns were analyzed.

Results

Of the total 39,494 articles, Korea's contribution accounted for 5.6% (2,161 articles), ranking fifth in the world in the number of publications. Korea ranked sixth (with 29,456) for total citations worldwide but ranked 17th (13.64) in terms of average citation per item and 14th (55) in terms of h-index. Korea showed the most prolific productivity in the field of sports medicine and arthroscopy. The institution that produced the highest number of publications was Seoul National University (n = 386, 17.9%).

Conclusions

Orthopedic research in South Korea demonstrated high productivity in terms of the number of publications in high-quality journals between 2008 and 2017. However, total citations and average citations per article were still relatively low. Efforts should be made to increase citation rates for further improvement in research productivity in the field of orthopedics.

Citation Analysis of Articles about Hand Surgery Published in Orthopaedic and Hand Surgery Journals

BACKGROUND

To date, little is known about the characteristics of highly cited studies in hand surgery compared with other orthopaedic subspecialties. We aimed to assess the position of hand surgery within the orthopedic surgery literature.

METHODS

We conducted a bibliographic analysis using the Web of Science database to review 1,568 articles published between January 2012 and December 2012 in 4 relevant general orthopedic and 2 hand surgery journals. We used the number of citations within 3 years of publication to measure the impact of each paper. To analyze prognostic factors using logistic regression analysis, we extracted data on orthopedic subspecialty, published journal, location of authorship, and type of study for all articles. For clinical studies, we also recorded details on study design and sample size.

RESULTS

Of eligible hand surgery articles (n = 307), the majority (62%) were case reports/series. Only 19% were comparative studies, comprising a significantly smaller proportion of comparative studies from other subspecialties in general orthopedic journals. Systematic reviews/meta-analyses generated a significantly higher number of average citations, whereas educational reviews were consistently cited less frequently than other study types (14.9 and 6.1 average citations, respectively). Being published in the Journal of Bone and Joint Surgery, American volume, having authorship in North America or Europe and Australia, focusing on subspecialties like hip & knee, sports, or shoulder, utilizing a comparative or randomized clinical trial study design, and having a larger sample size increased the odds of receiving more citations.

CONCLUSIONS

Clinical studies related to hand surgery published in general orthopedic journals are most often of lower quality study design. Having a larger sample size or using a comparative study or randomized clinical trial design can improve the quality of study and may ultimately increase the impact factor of hand surgery journals.

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

BACKGROUND

The citation rate of a research published article is an indicator of its quality and impact and contributes to the journal's impact factor. Within the orthopaedic sports medicine literature, predictors of citation rates have not been previously described.

PURPOSE

To identify characteristics of published articles that predict 5-year citation rates of studies in the orthopaedic sports medicine literature.

STUDY DESIGN

Cross-sectional study.

METHODS

Research articles published in The American Journal of Sports Medicine (AJSM), Arthroscopy: The Journal of Arthroscopic and Related Surgery, and Knee Surgery, Sports Traumatology, Arthroscopy (KSSTA) from 2012 were analyzed. Extracted characteristics of published articles included journal, author number, origin of study, first author degree, subject of study, study type, sample size, number of references and institutions, conflicts of interest, level of evidence, and 5-year citation rates. Multivariate logistic regression was used to determine predictors of greater than the mean number of citations at 5 years.

RESULTS

A total of 825 published articles ( AJSM, n = 313; Arthroscopy, n = 173; KSSTA, n = 339) were included in the final analysis. The mean number of 5-year citations was 23.2 (95% CI, 21.6-24.9; range, 1.0-260.0). AJSM had a significantly greater citation rate (32.4) than Arthroscopy (21.7) and KSSTA (15.2) ( P < .001 for both). Arthroscopy had a greater citation rate than KSSTA ( P = .008). Independent predictors of greater than the mean number of citations at 5 years were published articles in AJSM (odds ratio [OR], 5.17; 95% CI, 2.81-9.52; P < .0001), published articles of North American origin (OR, 1.79; 95% CI, 1.25-2.58; P = .002), and published articles regarding the hip (OR, 2.68; 95% CI, 1.08-6.67; P = .035).

CONCLUSION

Published articles in AJSM, those from North America, and those examining the hip were independent predictors of greater citation rates at 5 years.

How are risk ratios reported in orthopaedic surgery journals? A descriptive study of formats used to report absolute risks

PURPOSE

The numerical format in which risks are communicated can affect risk comprehension and perceptions of medical professionals. We investigated what numerical formats are used to report absolute risks in empirical articles, estimated the frequency of biasing formats and rated the quality of figures used to display the risks.

DESIGN

Descriptive study of reporting practices.

METHOD

We randomly sampled articles published in seven leading orthopaedic surgery journals during a period of 13 years. From these, we selected articles that reported group comparisons on a binary outcome (eg, revision rates in two groups) and recorded the numerical format used to communicate the absolute risks in the results section. The quality of figures was assessed according to published guidelines for transparent visual aids design.

OUTCOME MEASURES

Prevalence of information formats and quality of figures.

RESULTS

The final sample consisted of 507 articles, of which 14% reported level 1 evidence, 13% level 2 and 73% level 3 or lower. The majority of articles compared groups of different sizes (90%), reported both raw numbers and percentages (64%) and did not report the group sizes alongside (50%). Fifteen per cent of articles used two formats identified as biasing: only raw numbers (8%, '90 patients vs 100 patients') or raw numbers reported alongside different group sizes (7%, '90 out of 340 patients vs 100 out of 490 patients'). The prevalence of these formats decreased in more recent publications. Figures (n=79) had on average two faults that could distort comprehension, and the majority were rated as biasing.

CONCLUSION

Authors use a variety of formats to report absolute risks in scientific articles and are likely not aware of how some formats and graph design features can distort comprehension. Biases can be reduced if journals adopt guidelines for transparent risk communication but more research is needed into the effects of different formats.

Citation Rate Predictors in the Plastic Surgery Literature

BACKGROUND

The purpose of this study is to determine and characterize the scientific and nonscientific factors that influence the rate of article citation in the field of plastic surgery.

DESIGN

Cross-sectional study.

SETTING

We reviewed all entries in Annals of Plastic Surgery and Journal of Plastic, Reconstructive, and Aesthetic Surgery from January 1, 2007 to December 31, 2007; and Plastic and Reconstructive Surgery from January 1, 2007 to December 31, 2008. All scientific articles were analyzed and several article characteristics were extracted. The number of citations at 5 years was collected as the outcome variable. A multivariable analysis was performed to determine which variables were associated with higher citations rates.

RESULTS

A total of 2456 articles were identified of which only 908 fulfilled the inclusion criteria. Most studies were publications in the fields of reconstructive (26.3%) or pediatric/craniofacial (17.6%) surgery. The median number of citations 5 years from publication was 8. In the multivariable analysis, factors associated with higher citations rates were subspecialty field (p = 0.0003), disclosed conflict of interest (p = 0.04), number of authors (p = 0.04), and journal (p = 0.02).

CONCLUSION

We have found that higher level of evidence (or other study methodology factors) is not associated with higher citation rates. Instead, conflict of interest, subspecialty topic, journal, and number of authors are strong predictors of high citation rates in plastic surgery.

Knee Society Award Papers Are Highly Cited Works

BACKGROUND

Since 1993, The Knee Society has presented three annual awards recognizing the best research papers presented at the annual meetings. To date, no quantitative evaluation has determined whether the selection process identifies the most meritorious papers based on subsequent citations. In the absence of validation of this process, it is unclear whether the journal readership should view the award-winning papers as those with potentially greater impact for the specialty.

QUESTIONS/PURPOSES

(1) Are award papers cited both more than nonaward papers published in the same Knee Society proceedings issue of CORR(®) and more than all other knee research papers published in all issues of CORR(®) during any given year? (2) Does the award selection process identify potentially highly influential knee research?

METHODS

Subsequent citations for each award and nonaward paper published in The Knee Society proceedings issue for 2002 to 2008 were determined using the SCOPUS citation index. The citations for all papers on knee surgery published in CORR(®) during the same years were also determined.

RESULTS

Mean citations for an award paper were statistically greater than for a nonaward paper: 86 (SD 95; median 55; 95% confidence interval [CI] of the mean, 44-128) versus 33 (SD 30; median 24; 95% CI of the mean, 28-37; p < 0.001). Mean number of citations for award papers was also higher than for all other knee research papers published in nonproceedings issues of CORR(®): 86 (SD 95; median 55; 95% CI of the mean, 44-128) versus 30 (SD 31; median 20; 95% CI for the mean, 25-35; p < 0.001). Twelve of the 22 (54.6%) award papers were in the top five cited papers from the proceedings issue for the respective year versus 24 of the 190 (12.6%) of the nonaward papers (difference in the percentages is 41.9% and the 95% CI for the risk difference is 20.6%-63.3%; p < 0.001). In 3 of 7 years, an award paper was the most cited knee paper published in CORR(®).

CONCLUSIONS

The selection process for The Knee Society scientific awards identifies potentially influential papers that are likely to be highly cited in future research articles about the knee.

CLINICAL RELEVANCE

The selection process for Knee Society Award Papers appears to identify papers that are potentially influential in the field of knee surgery and are likely to be highly cited in future published articles. As such, these award papers deserve special attention from the readership.

The Quality of Cost-Utility Analyses in Orthopedic Trauma

As health care in the United States transitions toward a value-based model, there is increasing interest in applying cost-effectiveness analysis within orthopedic surgery. Orthopedic trauma care has traditionally underemphasized economic analysis. The goals of this review were to identify US-based cost-utility analysis in orthopedic trauma, to assess the quality of the available evidence, and to identify cost-effective strategies within orthopedic trauma. Based on a review of 971 abstracts, 8 US-based cost-utility analyses evaluating operative strategies in orthopedic trauma were identified. Study findings were recorded, and the Quality of Health Economic Studies (QHES) instrument was used to grade the overall quality. Of the 8 studies included in this review, 4 studies evaluated hip and femur fractures, 3 studies analyzed upper extremity fractures, and 1 study assessed open tibial fracture management. Cost-effective interventions identified in this review include total hip arthroplasty (over hemiarthroplasty) for femoral neck fractures in the active elderly, open reduction and internal fixation (over nonoperative management) for distal radius and scaphoid fractures, limb salvage (over amputation) for complex open tibial fractures, and systems-based interventions to prevent delay in hip fracture surgery. The mean QHES score of the studies was 79.25 (range, 67-89). Overall, there is a paucity of cost-utility analyses in orthopedic trauma; however, the available evidence suggests that certain operative interventions can be cost-effective. The quality of these studies, however, is fair, based on QHES grading. More attention should be paid to evaluating the cost-effectiveness of operative intervention in orthopedic trauma.

Cost-effectiveness analyses in orthopaedic sports medicine: a systematic review

BACKGROUND

As increasing attention is paid to the cost of health care delivered in the United States (US), cost-effectiveness analyses (CEAs) are gaining in popularity. Reviews of the CEA literature have been performed in other areas of medicine, including some subspecialties within orthopaedics. Demonstrating the value of medical procedures is of utmost importance, yet very little is known about the overall quality and findings of CEAs in sports medicine.

PURPOSE

To identify and summarize CEA studies in orthopaedic sports medicine and to grade the quality of the available literature.

STUDY DESIGN

Systematic review.

METHODS

A systematic review of the literature was performed to compile findings and grade the methodological quality of US-based CEA studies in sports medicine. The Quality of Health Economic Studies (QHES) instrument and the checklist by the US Panel on Cost-effectiveness in Health and Medicine were used to assess study quality. One-sided Fisher exact testing was performed to analyze the predictors of high-quality CEAs.

RESULTS

Twelve studies met inclusion criteria. Five studies examined anterior cruciate ligament reconstruction, 3 studies examined rotator cuff repair, 2 examined autologous chondrocyte implantation, 1 study examined hip arthroscopic surgery, and 1 study examined the operative management of shoulder dislocations. Based on study findings, operative intervention in sports medicine is highly cost-effective. The quality of published evidence is good, with a mean quality score of 81.8 (range, 70-94). There is a trend toward higher quality in more recent publications. No significant predictor of high-quality evidence was found.

CONCLUSION

The CEA literature in sports medicine is good; however, there is a paucity of studies, and the available evidence is focused on a few procedures. More work needs to be conducted to quantify the cost-effectiveness of different techniques and procedures within sports medicine. The QHES tool may be useful for the evaluation of future CEAs.

Current status of cost utility analyses in total joint arthroplasty: a systematic review

BACKGROUND

Total joint arthroplasty (TJA), although considered to be highly beneficial, is associated with substantial costs to the US healthcare system. Cost utility analysis has become an increasingly important means to objectively evaluate the value of a healthcare intervention from the perspective of both extending the quantity and improving the quality of life. Relatively little is known about the overall cost utility analysis evidence base in TJA.

QUESTIONS/PURPOSES

The goals of this review were to (1) determine the cost utility of TJA interventions; (2) critically assess the quality of published US-based cost utility analyses using the Quality of Health Economic Studies instrument; and (3) determine what characteristics were common among studies receiving a high quality score.

METHODS

A systematic review of the literature using the MEDLINE database was performed to compile findings and critically appraise US-based cost utility analysis studies for total hip and knee arthroplasty. Based on review of 676 identified articles, 23 studies were included. We used the Quality of Health Economic Studies instrument to assess study quality and one-sided Fisher's exact tests were applied to analyze the predictors of high-quality cost utility analysis.

RESULTS

Very few studies compare the cost utility of TJA versus nonoperative intervention; however, the available evidence suggests that TJA can be cost-saving and is highly cost-effective compared with conservative management of end-stage arthritis. The majority of identified studies are focused on the cost utility of new implant technologies or comparisons among surgical alternatives. These studies suggest that the upfront costs associated with new technologies are cost-effective when there is a major reduction in a future cost. The quality of identified studies is quite high (Quality of Health Economic Studies Instrument score: mean 86.5; range, 63-100). National funding source (p = 0.095) and lifetime horizon for analysis (p = 0.07) correlate with high-quality evidence but do not reach significance.

CONCLUSIONS

Over the past 15 years, there has been a major increase in the volume of cost utility analyses published in total hip and knee arthroplasty. The quality of cost utility analyses published during that period is good. As increasing attention is paid to value in US health care, more attention should be paid to understanding the cost utility of TJA compared with nonoperative treatment modalities. Future studies may also look to incorporate patient willingness to pay.

Is quality and completeness of reporting of systematic reviews and meta-analyses published in high impact radiology journals associated with citation rates?

Purpose

The purpose of this study is to determine whether study quality and completeness of reporting of systematic reviews (SR) and meta-analyses (MA) published in high impact factor (IF) radiology journals is associated with citation rates.

Methods

All SR and MA published in English between Jan 2007–Dec 2011, in radiology journals with an IF >2.75, were identified on Ovid MEDLINE. The Assessing the Methodologic Quality of Systematic Reviews (AMSTAR) checklist for study quality, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist for study completeness, was applied to each SR & MA. Each SR & MA was then searched in Google Scholar to yield a citation rate. Spearman correlation coefficients were used to assess the relationship between AMSTAR and PRISMA results with citation rate. Multivariate analyses were performed to account for the effect of journal IF and journal 5-year IF on correlation with citation rate. Values were reported as medians with interquartile range (IQR) provided.

Results

129 studies from 11 journals were included (50 SR and 79 MA). Median AMSTAR result was 8.0/11 (IQR: 5–9) and median PRISMA result was 23.0/27 (IQR: 21–25). The median citation rate for SR & MA was 0.73 citations/month post-publication (IQR: 0.40–1.17). There was a positive correlation between both AMSTAR and PRISMA results and SR & MA citation rate; ρ=0.323 (P=0.0002) and ρ=0.327 (P=0.0002) respectively. Positive correlation persisted for AMSTAR and PRISMA results after journal IF was partialed out; ρ=0.243 (P=0.006) and ρ=0.256 (P=0.004), and after journal 5-year IF was partialed out; ρ=0.235 (P=0.008) and ρ=0.243 (P=0.006) respectively.

Conclusion

There is a positive correlation between the quality and the completeness of a reported SR or MA with citation rate which persists when adjusted for journal IF and journal 5-year IF.

Cost-utility analyses in spine care: a qualitative and systematic review

STUDY DESIGN

Systematic review.

OBJECTIVE

A systematic review was performed to identify US-based cost-utility analyses (CUA) studies in spine care and to critically evaluate the quality of the available literature.

SUMMARY OF BACKGROUND DATA

There has been a recent trend in the United States toward increased publication of economic analyses in spine care. The cost-effectiveness of spine interventions and the quality of published literature is not well understood.

METHODS

A MEDLINE search was conducted to identify cost analyses in spine care. Articles were excluded on the basis of the following criteria: nonspine care, nonoperative, non-US based, nonclinical, and not CUA. Of the 424 screened articles, 20 met inclusion criteria. Quality of studies was assessed using the Quality of Health Economic Studies instrument.

RESULTS

Evidence for the cost-effectiveness of operative spinal intervention is varied. The majority of available studies report favorable cost-effectiveness ratios, however, a few studies suggest that certain operative interventions are not cost-effective. Average Quality of Health Economic Studies score of all included studies was 75.1 (60-93). The quality of evidence is variable and there are a number of weaknesses in the available literature, most significant of which is that few studies adopt a long-term time horizon or have sufficient follow-up (N = 3/20). High Quality of Health Economic Studies scoring studies were more likely to have sensitivity analysis (P = 0.016), societal cost perspective (P = 0.014), and a funding disclosure (P = 0.03).

CONCLUSION

There is a small but rapidly growing body of US-based CUA in spine care. The quality of CUA evidence is variable but there are significant opportunities to strengthen future CUA studies in spine. This study highlights the need for more attention to CUA research and the quality of these studies in spine care.

Bibliometric analysis of factors predicting increased citations in the vascular and endovascular literature

BACKGROUND

Dissemination of research findings in the scientific community is reflected by the citation count. Our objective was to investigate the relative citation impact of vascular research studies and identify potential predictors of increased citation rates.

METHODS

Articles published in leading journals of vascular and general surgery (Journal of Vascular Surgery, European Journal of Vascular and Endovascular Surgery, Journal of Endovascular Therapy, Annals of Vascular Surgery and Annals of Surgery, British Journal of Surgery, Journal of the American College of Surgeons, and JAMA Surgery) during a 4-month period were identified through electronic databases. Variables potentially associated with increased citation rates, including subject, design, title characteristics, article length, bibliographic references, authorship, geographic distribution, interdisciplinary collaboration, article access, and funding, were assessed in univariate and multiple linear regression models through December 2012.

RESULTS

A total of 226 articles with a total number of 4,605 citations were identified. Univariate analysis revealed that endovascular-related studies, study design, studies reporting design in the title, long articles, and studies with high number of references were associated with higher citation rates. On multivariate analysis, 3 variables were found to independently predict the number of citations: study subject (endovascular-related studies; regression coefficient [95% confidence interval], 0.474 [0.240-0.708]; P < 0.001); study design (randomized controlled trial; regression coefficient [95% confidence interval], 0.575 [0.145-1.005]; P = 0.009); and article length (number of pages; regression coefficient [95% confidence interval], 0.069 [0.016-0.123]; P = 0.011).

CONCLUSIONS

Authors involved in vascular research may enhance the impact of their work by embarking on research strategies of high methodologic quality and pursuing work related with new technologies and evolving endovascular therapies.

Citations alone were enough to predict favorable conclusions in reviews of neuraminidase inhibitors

OBJECTIVES

To examine the use of supervised machine learning to identify biases in evidence selection and determine if citation information can predict favorable conclusions in reviews about neuraminidase inhibitors.

STUDY DESIGN AND SETTING

Reviews of neuraminidase inhibitors published during January 2005 to May 2013 were identified by searching PubMed. In a blinded evaluation, the reviews were classified as favorable if investigators agreed that they supported the use of neuraminidase inhibitors for prophylaxis or treatment of influenza. Reference lists were used to identify all unique citations to primary articles. Three classification methods were tested for their ability to predict favorable conclusions using only citation information.

RESULTS

Citations to 4,574 articles were identified in 152 reviews of neuraminidase inhibitors, and 93 (61%) of these reviews were graded as favorable. Primary articles describing drug resistance were among the citations that were underrepresented in favorable reviews. The most accurate classifier predicted favorable conclusions with 96.2% accuracy, using citations to only 24 of 4,574 articles.

CONCLUSION

Favorable conclusions in reviews about neuraminidase inhibitors can be predicted using only information about the articles they cite. The approach highlights how evidence exclusion shapes conclusions in reviews and provides a method to evaluate citation practices in a corpus of reviews.

Discrepancies in spine surgeon conflict of interest disclosures between a national meeting and physician payment listings on device manufacturer web sites

BACKGROUND CONTEXT

Previous studies have identified inconsistencies in physician conflict-of-interest disclosures at academic meetings. The Physician Payment Sunshine Act (PPSA) will require industry to disclose anything of value given to physicians by 2014. In preparation, some spine device companies have begun reporting payments online.

PURPOSE

To evaluate potential inconsistencies between physician disclosures and payments reported by industry before the PPSA implementation.

STUDY DESIGN

Comparison of publically available disclosure/payment data.

PATIENT SAMPLE

Physicians participating in the 2011 North American Spine Society (NASS) annual meeting and physicians listed on the 2010 physician payment web sites of Medtronic and Depuy Spine.

METHODS

Disclosures of participants at NASS were compared with the published Medtronic and Depuy Spine physician payments. The periods reflected by the disclosures compared should have coincided (except the Depuy site, which was only listed for one quarter of the NASS disclosure period). Discrepancies were noted whenever participant disclosures and company listings did not match as well as whenever payment ranges did not overlap. Fisher's exact test was used to compare disclosure discrepancy rates based on Medtronic payment size. No funding was received for this work. The authors report no conflicts of interest directly related to this study; however, one of the authors does do consulting unrelated to this study.

RESULTS

Medtronic and Depuy Spine were disclosed by 12.1% and 8.75% of NASS participants, respectively. Based on NASS disclosures, 52.4% of NASS participants affiliated with Medtronic had their disclosures inaccurately reflected on the Medtronic web site. Based on Medtronic payment postings, 45.7% of NASS participants listed on Medtronic's webpage had discrepancies in their NASS disclosures. Those who received payments <$100,000 from Medtronic were more likely to have discrepancies in their disclosures than those who received payments >$100,000 (p=.009). Based on Depuy Spine payment postings, 30% of NASS participants listed on Depuy Spine's site had discrepancies in their NASS disclosures.

CONCLUSIONS

Discrepancy rates between what spine surgeons disclosed at NASS 2011 and what companies reported for their consultants were high. This is concerning given the passage of the PPSA as well as the increased public visibility of potential discrepancies. More uniform practices will certainly be necessary.

Bibliometrics of systematic reviews: analysis of citation rates and journal impact factors

BACKGROUND

Systematic reviews are important for informing clinical practice and health policy. The aim of this study was to examine the bibliometrics of systematic reviews and to determine the amount of variance in citations predicted by the journal impact factor (JIF) alone and combined with several other characteristics.

METHODS

We conducted a bibliometric analysis of 1,261 systematic reviews published in 2008 and the citations to them in the Scopus database from 2008 to June 2012. Potential predictors of the citation impact of the reviews were examined using descriptive, univariate and multiple regression analysis.

RESULTS

The mean number of citations per review over four years was 26.5 (SD ± 29.9) or 6.6 citations per review per year. The mean JIF of the journals in which the reviews were published was 4.3 (SD ± 4.2). We found that 17% of the reviews accounted for 50% of the total citations and 1.6% of the reviews were not cited. The number of authors was correlated with the number of citations (r = 0.215, P < 0.001). Higher numbers of citations were associated with the following characteristics: first author from the United States (36.5 citations), an ICD-10 chapter heading of Neoplasms (31.8 citations), type of intervention classified as Investigation, Diagnostics or Screening (34.7 citations) and having an international collaboration (32.1 citations). The JIF alone explained more than half of the variation in citations (R(2) = 0.59) in univariate analysis. Adjusting for both JIF and type of intervention increased the R2 value to 0.81. Fourteen percent of reviews published in the top quartile of JIFs (≥ 5.16) received citations in the bottom quartile (eight or fewer), whereas 9% of reviews published in the lowest JIF quartile (≤ 2.06) received citations in the top quartile (34 or more). Six percent of reviews in journals with no JIF were also in the first quartile of citations.

CONCLUSIONS

The JIF predicted over half of the variation in citations to the systematic reviews. However, the distribution of citations was markedly skewed. Some reviews in journals with low JIFs were well-cited and others in higher JIF journals received relatively few citations; hence the JIF did not accurately represent the number of citations to individual systematic reviews.

Demographics of disclosure of conflicts of interest at the 2011 annual meeting of the American Academy of Orthopaedic Surgeons

BACKGROUND

There is growing concern regarding conflicts of interest in orthopaedic research and education. Because of their potential influence on orthopaedic practice, conflicts of interest among participants in the educational programs of the American Academy of Orthopaedic Surgeons (AAOS) are of particular interest.

METHODS

We analyzed the voluntarily disclosed conflicts of interest listed in the Final Program of the 2011 Annual Meeting of the AAOS for the relevant program committees as well as for presentations in the disciplines of pediatric orthopaedic surgery, spine, and sports medicine/arthroscopy.

RESULTS

Conflicts of interest were disclosed by participants for each of the program committees and for over 75% of the presentations. Conflicts of interest were disclosed for 100% of the featured symposia, 80% of the scientific exhibits, 76% of the podium presentations, and 75% of the posters. Over half (53%) of the disclosures were for paid consultancy, 51% were for research support for the principal investigator, 41% were for paid presentations, 39% were for royalties, and 39% were for stock. The highest number of disclosures for an individual author was thirty-seven. The number of disclosures per author was significantly (p &lt; 0.001) correlated to the number of presentations per author. Disclosures were associated with 379 different companies; relationships with a relatively small number (twenty-six, 7%) of these companies were listed in the disclosures for 67% of the presentations.

CONCLUSIONS

Voluntarily disclosed conflicts of interest were common at the 2011 AAOS Annual Meeting, especially for the featured symposia. In view of the previously documented frequency of undisclosed conflicts of interest, as well as the previously documented effects of conflicts of interest on research design, conduct, and conclusion, it may be time to consider improved strategies for ensuring the accuracy and completeness of disclosure and for managing the biasing effects of conflicts of interest.

The impact of article length on the number of future citations: a bibliometric analysis of general medicine journals

Background

The number of citations received is considered an index of study quality and impact. We aimed to examine the factors associated with the number of citations of published articles, focusing on the article length.

Methods

Original human studies published in the first trimester of 2006 in 5 major General Medicine journals were analyzed with regard to the number of authors and of author-affiliated institutions, title and abstract word count, article length (number of print pages), number of bibliographic references, study design, and 2006 journal impact factor (JIF). A multiple linear regression model was employed to identify the variables independently associated with the number of article citations received through January 2012.

Results

On univariate analysis the JIF, number of authors, article length, study design (interventional/observational and prospective/retrospective), title and abstract word count, number of author-affiliated institutions, and number of references were all associated with the number of citations received. On multivariate analysis with the logarithm of citations as the dependent variable, only article length [regression coefficient: 14.64 (95% confidence intervals: (5.76–23.50)] and JIF [3.37 (1.80–4.948)] independently predicted the number of citations. The variance of citations explained by these parameters was 51.2%.

Conclusion

In a sample of articles published in major General Medicine journals, in addition to journal impact factors, article length and number of authors independently predicted the number of citations. This may reflect a higher complexity level and quality of longer and multi-authored studies.

Impact factors of orthopaedic journals between 2000 and 2010: trends and comparisons with other surgical specialties

PURPOSE

The impact factors (IF) of orthopaedic journals is an important component in determining the future of orthopaedic research funding. We aim to characterise the trend in journal IF over the last decade and draw comparisons with other surgical specialties.

METHODS

We conducted an analysis of impact factors from Journal Citation Reports between 2000 and 2010.

RESULTS

Between 2000 and 2010 the number of orthopaedic journals increased from 24 to 41, more than any other surgical specialty and the mean IF increased from 0.842 to 1.400. Journals printed in the English language had a significantly higher IF in the year 2010 (1.64 vs. 0.33, p = 0.01) than those printed in other languages. English language journals published in the US had significantly higher mean 2010 IF (1.932 vs. 1.243, p = 0.025) than those published in Europe, and this had changed compared with 2000 mean IF (0.978 Vs. 0.704, p = 0.360). Orthopaedics was ranked sixth out of 11 surgical subspecialties in 2000 but dropped to seventh out of 11 in 2010.

CONCLUSIONS

The quality of orthopaedic journals has significantly increased over the last decade and this has been accompanied by a rise in mean IF. It is important that orthopaedics continues to improve the quality of research, which may help orthopaedic researchers secure funding in the future.

A methodological systematic review of early versus late stabilization of thoracolumbar spine fractures

OBJECTIVE

The optimal timing of stabilization in patients with traumatic thoracolumbar fractures remains controversial. There is currently a lack of consensus on the timing of surgical stabilization, which is limited by the reality that a randomized controlled trial to evaluate early versus late stabilization is difficult to perform. Therefore, the objective of this study was to determine the benefits, safety and costs of early stabilization compared with late stabilization using data available in the current literature.

METHODS

An electronic literature search was performed in Medline, Embase, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials for relevant studies evaluating the timing of surgery in patients with thoracolumbar fractures. Two reviewers independently analyzed and selected each study on the basis of the eligibility criteria. The quality of the included studies was assessed using the Grading of Recommendations Assessment, Development, and Evaluation system (GRADE). Any disagreements were resolved by consensus.

RESULTS

Ten studies involving 2,512 subjects were identified. These studies demonstrated that early stabilization shortened the hospital length of stay, intensive care unit length of stay, ventilator days and reduced morbidity and hospital expenses for patients with thoracic fractures. However, reduced morbidity and hospital expenses were not observed with stabilization of lumbar fractures. Owing to the very low level of evidence, no conclusion could be made regarding the effect of early stabilization on mortality.

CONCLUSIONS

We could adhere to the recommendation that patients with traumatic thoracolumbar fractures should undergo early stabilization, which may reduce the hospital length of stay, intensive care unit length of stay, ventilator days, morbidity and hospital expenses, particularly when the thoracic spine is involved. Individual patient characteristics should be concerned carefully. However, the definite conclusion cannot be made due to the heterogeneity of the included studies and low level of evidence. Further prospective studies are required to confirm whether there are benefits to early stabilization compared with late stabilization.

Citation analysis of the dry eye literature

PURPOSE

The purpose of this study was to characterize the literature associated with the dry eye field.

METHODS

An advanced search using Thomson Reuters Web of Science's Science Citation Index yielded 7,225 unique articles related to dry eye disease. All results underwent visual inspection to ensure that the final list included only literature associated with dry eye in some way. The most frequently cited articles were characterized by number of citations, author, institution, country of origin, year of publication, and source title.

RESULTS

The h-index (Hirsch index) of literature associated with dry eye was 100. The two most frequent topics among the top 25 cited articles were lacrimal gland structure and physiology and treatment methods for ocular surface disease. The top-cited author, institution, country, and source title were Kazuo Tsubota, Harvard University, the United States, and Investigative Ophthalmology and Visual Science, respectively. The most highly cited article associated with the dry eye field (n=1, 180) was "Preliminary criteria for the classification of Sjogrens syndrome - Results of a prospective concerted action supported by the European Community," authored in 1993 by C. Vitali.

CONCLUSIONS

This analysis reviewed the citation frequency of the top-cited articles related to dry eye disease. This information aids understanding of the history and development of dry eye research, in addition to the impact and characteristics of the contributors to the field.

Level of evidence of presentations at American Academy of Orthopaedic Surgeons annual meetings

BACKGROUND

The American Academy of Orthopaedic Surgeons (AAOS) Annual Meeting is a major international forum for scientific exchange and education. The purpose of this study was to evaluate the level of evidence of papers and posters presented at the 2001, 2004, 2007, and 2010 AAOS meetings to determine trends in the quality of study designs between the years 2001 and 2010.

METHODS

Abstracts for AAOS presentations from 2001 (288 papers and 468 posters), 2004 (290 papers and 466 posters), 2007 (525 papers and 541 posters), and 2010 (720 papers and 569 posters) were independently evaluated by three reviewers. The level of evidence of each presentation was determined based on the AAOS classification system. The results were subdivided according to orthopaedic subspecialty and type of presentation.

RESULTS

In subsequent years, there was a substantial increase in the percentage of Level I studies (2% in 2001, 3% in 2004, 5% in 2007, and 7% in 2010), Level II studies (15% in 2001, 18% in 2004, 23% in 2007, and 29% in 2010), and Level III studies (22% in 2001, 26% in 2004, 29% in 2007, and 33% in 2010), with a concomitant decrease in the percentage of Level IV studies (62% in 2001, 54% in 2004, 43% in 2007, and 31% in 2010). Overall, there was a significant nonrandom improvement in the level of evidence of presentations over the study period (p &lt; 0.001). This trend was consistent across all orthopaedic subspecialties and in both the paper and the poster subgroups.

CONCLUSIONS

The level of evidence of studies presented at the AAOS Annual Meeting is steadily increasing, which signifies a mark of continual improvement in the quality of the scientific program.

The results of TKA: what the registries don't tell us

National registries have provided valuable feedback to surgeons and improved patient care by decreasing revision rates and identifying defective or poorly performing devices. Although there have been thousands of peer review publications in the literature, significant gaps exist in relevant knowledge relating to performance of hip and knee devices due to shortcomings in many published studies. Most studies come from specialty centers and may not reflect the results that can be expected from devices in widespread use. Sample sizes are frequently small, and studies are underpowered to draw major conclusions or to stratify data based on clinically important variables. National registries effectively address many of these problems, but also have shortcomings. Registry data are now being used to promote specific devices, which opens the door to potential abuse of this information. While device design can impact implant survival, other factors, such as surgical technique, surgeon, hospital, patient factors, and even country, may have far more impact on revision rate than implant design. Revision rates often differ among different designs by as little as 5% to 10% while these previously mentioned factors can result in differences in revision rate and order of magnitude higher. Failure to control these numerous other potentially confounding variables can lead to false or misleading conclusions. In general, registries are far more effective in identifying poorly performing devices that manifest in clusters of failures than in identifying small differences in performance among relatively well-designed devices. It is important for surgeons interpreting data generated from registries to be aware of potential pitfalls of these data as well as their value.