The Characteristics and Level of Evidence of Clinical Studies Published in 5 Leading Orthodontic Journals

The level of evidence in prosthodontics in relation to author's characteristics: An analysis of three leading prosthodontics journals

Purpose

The purpose of this study was to examine the level of evidence (LOE) characteristics and associated factors that change over time in three leading prosthodontics journals.

Materials and methods

Articles published in The Journal of Prosthetic Dentistry (JPD), International Journal of Prosthodontics (IJP), and Journal of Prosthodontics (JP) in 2013 and 2020 were reviewed by eight independent reviewers. After applying exclusion and inclusion criteria, the number of authors, the corresponding author's educational degree, corresponding author's origin in each clinical research article were recorded. The included articles were rated by reviewers according to the level of evidence criteria and proposed level of evidence-associated factors. Descriptive statistics, univariable, and binary logistic regression analysis were performed to investigate dependent variables and potentially associated factors. All independent variables with a significant effect were analyzed by using a multivariable test. The entry and exit alpha level were set at αE = 0.15. The statistical significance was set at α = 0.05.

Results

A total of 439 articles from 3 selected journals for the years studied met the inclusion criteria. The percentages of level 1, 2, 3, 4, and 5 articles were 2.7 %, 11.4 %, 9.6 %, 13.4 % and 62.9 %, respectively. Univariable analysis results demonstrated significant associations related to the number of authors (P = 0.005), the corresponding author's educational degree (P = 0.022), and the corresponding author's geographic origin (P = 0.042). Multivariable analysis results demonstrated significant associations related to the number of authors (P = 0.002), and the corresponding author's geographic origin (P = 0.014).

Conclusions

The number of authors, CA degree, and CA origin had a significant association with the LOE of included prosthodontic studies. Although there was an increase in the number of publications from 2013 to 2020, the level of evidence trend shows no improvement over the years.

25 years of Clinical Implant Dentistry and Related Research (CIDRR): A modern bibliometric and Altmetrics network analysis

INTRODUCTION

Since its establishment in 1999, the journal of Clinical Implant Dentistry and Related Research (CIDRR) has consistently disseminated notable clinical and translational research within the domain of oral implantology. As the journal approaches its milestone 25th anniversary, this study endeavors to systematically delineate the publication trends, level of evidence, and bibliometric indices characterizing the initial quarter-century of CIDRR's scholarly activity. Notably, the investigation adopts a contemporary methodology by incorporating Altmetric analysis, thereby enriching the evaluation with an assessment of the broader societal and online impact of the published research.

METHODS

A comprehensive search was performed in SCOPUS and PubMed to access the bibliographic data of all articles published in the journal from 1999 to 2024. Additionally, Altmetric database was used to obtain social media attention scores (AAS). Journal's overall performance via impact factor and quartile range was assessed. Most cited papers were identified and the most prolific authors, institutions and countries and the collaboration networks among those were assessed. The level of evidence of all articles was determined based on Oxford level of evidence scale. All articles were categorized based on their major topic in the field of implant dentistry.

RESULTS

Throughout its first 25 years of activity, CIDRR published 1912 articles with an annual growth rate of 2.67% and consistently being ranked at Q1 quartile in "Dentistry (miscellaneous)" and "Oral Surgery" journal categories. When clinical studies are considered, level I and II evidence constituted 22.82% and 11.82% of all articles, respectively. Sweden, the USA, and Italy as well as Göteborgs Universitet, Sahlgrenska Akademin. and Malmö Högskola were the most prolific countries and institutions respectively. "Implant system/design/characteristics," "Bone Augmentation," and "Implant Prosthesis" were the top most investigated topics.

CONCLUSIONS

The examination of the journal's initial 25 years highlighted that CIDRR has surpassed similar dental research journals in publishing a greater number of high-level evidence articles. It also showcased diverse country- and author-collaboration networks. However, the journal's social media presence is still evolving. This article, presenting a comprehensive overview of the journal's scientometric and bibliographic activities, serves as a valuable reference for researchers, clinicians, and stakeholders, offering insights into both traditional and contemporary perspectives.

DENTAL PATIENT-REPORTED OUTCOMES UPDATE 2023

The emergence and rapid development of disruptive innovations are quickly turning our profession into personalized dentistry, built upon evidence-based, data-oriented, and patient-centered research. In order to help improve the quality and quantity of patient-centered evidence in dentistry, further promote the wide and standard use of dental patient-reported outcomes (dPROs) and dental patient-reported outcome measures (dPROMs), the Journal of Evidence-Based Dental Practice has put together this special issue, the third of a series entitled Dental Patient-Reported Outcomes Update. A total of 7 solicited articles are collected in this issue. To put them into a broader perspective, this review provides a concise summary of key, selected PRO and dPRO articles published during 2023. A brief introduction to those articles included in this Special Issue follows. Four main domains are covered in this Special Issue: (1) dPROs and digital dentistry, (2) standardization of dPRO-related methodology, (3) current usage of dPROs and dPROMs in published research, and (iv) the significance and relevance of dPRO usage.

THE USE OF DENTAL PATIENT-REPORTED OUTCOMES AMONG COMPARATIVE OBSERVATIONAL STUDIES IN ORTHODONTICS: A METHODOLOGICAL STUDY

OBJECTIVE

To identify and summarize the presence and characteristics of dental patient-reported outcomes (dPROs) and dental patient-reported outcome measures (dPROMs) within comparative observational studies published in 5 leading orthodontic journals.

METHODS

Electronic searching was performed to identify intervention (therapeutic or preventive) related comparative observational studies published in selected journals between 2015 and 2021. Two authors extracted the characteristics of each included study independently and in duplicate and summarized the dPROs and dPROMs used in these studies. All dPROs were classified into 2 general types (oral health-related quality of life [OHRQoL] and others), while dPROMs were divided into 3 categories (single-item questionnaires, generic multiple-item questionnaires, and specific multiple-item questionnaires). In addition, dPROMs were examined, if they evaluated the 4 dimensions of OHRQoL (oral function, orofacial pain, orofacial appearance, and psychosocial impact).

RESULTS

A total of 683 observational studies were eligible and included of which 117 (17.1%) used dPROs and dPROMs. Seven different dPROs (OHRQoL, patients' satisfaction with treatment, preferences, concerns, compliance, duration, and unwanted events) and 33 different dPROMs (including 8 single-item questionnaires, 11 generic multiple-item questionnaires, and 14 specific multiple-item questionnaires) were identified in these studies. OHRQoL was the most commonly used dPRO (92/117, 78.6%), while Oral Health Impact Profile 14 (OHIP-14) was the most frequently used dPROM (20/92, 21.7%). In terms of study design, cross-sectional studies had the highest proportion of dPRO usage (62/148, 41.9%), followed by cohort studies (63/505, 12.5%) and case-control studies (1/30, 3.3%).

CONCLUSIONS

Only one-sixth of comparative observational studies published in leading orthodontic journals could reflect patients' perspectives. Observational studies in orthodontics need to provide more patient-important information through the use of dPROs and dPROMs.

Diversity of authors in the British Journal of Orthodontics and Journal of Orthodontics over the last 50 years

AIMS

To explore any changes in the perceived gender and affiliation of first authors of papers published in the British Journal of Orthodontics (BJO) and Journal of Orthodontics (JO), over the last 50 years.

METHODS

Electronic hand searches of the BJO and JO from 1973 to 2021, were undertaken to identify research and clinical papers published the first volume of the BJO (1973-74) and then the first two volumes of each subsequent decade i.e. 1980-81; 1990-91 to 2020-21. Articles such as Editorials, Product Updates and Abstract summaries, were excluded.The perceived gender of the first author was identified from their forename, internet sources and/or personal knowledge, where possible. The country of the first author's affiliation was identified from the author details stated in the papers. The countries were then grouped into geographical areas.

RESULTS

A total of 385 papers were identified with a steady increase from 1973 to 2021. There was a statistically significant increase in papers published by authors who were perceived to be female (odds ratio 8.33; 95% CI 4.75, 14.64). The increase in papers published by non-UK affiliated first authors was significant (odds ratio 5.01; 95% CI 2.78, 9.02).

CONCLUSIONS

The Journal has seen a significant change, over the last 50 years, in its authorship profile from nearly exclusively male, UK based authors to more than 60% of published papers having a first author who was perceived as being female and 37% originating from outside the UK.

Publication performance and trends in bruxism research: A bibliometric analysis

BACKGROUND

Bruxism is an umbrella term that encompass a multidimensional spectrum of masticatory muscle activities.

OBJECTIVE

The purpose of this study was to do a bibliometric analysis including citation performance in the research topic of bruxism, by using an innovative method including details of article title, author keyword, KeyWords Plus and abstracts.

METHODS

The data were retrieved 2022-12-19 from the Clarivate Analytics Web of Science Core Collection, and the online version of the Science Citation Index Expanded (SCI-EXPANDED) for studies published 1992 to 2021. To evaluate research trends, the distribution of keywords in the article title and author-selected keywords were used.

RESULTS

The search yielded 3233 documents in SCI-EXPANDED, of which 2598 were of the document-type 'articles' published in 676 journals. The analysis of the articles revealed that "bruxism/sleep bruxism," "electromyography," "temporomandibular disorders" and "masticatory muscles" are the most used keywords by the authors. Further, the most frequently cited study was published 9 years ago and handles the present definition of bruxism.

CONCLUSION

The most productive authors and those with the highest performance have some common features; they have several national and international collaborations; and they have published articles about the definition, aetiology/pathophysiology and prevalence of bruxism, all senior researchers in the field of TMD. Hopefully, based on this study, researchers and clinicians will have information to be stimulated to outline future research projects on bruxism-related aspects, and to initiate new international or multinational collaborations.

Level of evidence analysis of the Saudi Dental Journal: A bibliometric analysis of publications from 2012 to 2021

Objectives

The Level of Evidence (LOE) ranking system is used to measure the methodological quality of research. This study aimed to analyze and evaluate the trends of LOEs in articles published in the Saudi Dental Journal (SDJ) between 2012 and 2021.

Methodology

The bibliometric details of all articles published from 2012 to 2021 were extracted from the SDJ website. All articles, expect editorials, were included in the analysis. The articles were divided based on LOEs, dental specialties, number of authors, and centers. The citation metrics were obtained from Google Scholar, and the statistical analysis was performed using JMP Pro 15.2.0 software.

Results

Five hundred twenty-two articles were selected for analysis. They had an average of 21.19 citations per article, and a growing trend in the number of articles was observed. Authors from 40 countries contributed to the articles, with the most contributions from the Kingdom of Saudi Arabia. Most articles (n = 269; 51.53%) were LOE IV and V, while a low proportion (5.56%) were LOE I articles. Aside from miscellaneous articles, periodontics composed most of the LOE I studies, followed by endodontics, and oral and maxillofacial Surgery (OMFS). Orthodontics had the highest number of LOE II studies, pediatric dentistry had the most LOE IV, and prosthodontics had the most LOE V studies. No significant correlations were found between LOE and the number of authors or centers. However, a significant correlation was found in the distribution of LOE contributed by academic institutes.

Conclusion

The study results highlight that most articles were LOE IV and V, whereas nominal LOE I articles were found. Furthermore, there is a need to encourage dental scientists to carry out high-quality evidence studies. Professional dental societies can play a pivotal role in this regard.

Characteristics, level of evidence, and impact of clinical studies on peri-implantitis: 2017 to 2021

BACKGROUND

The level of evidence (LOE) is an important tool in current evidence-based practice and clinical research. However, in clinical studies on peri-implantitis, the present status of the LOE and its association with research impact remains to be determined. The present study aimed to gather the characteristics and LOE of clinical studies on peri-implantitis conducted from 2017 to 2021 and assess the association of the LOE with social and scientific impact.

METHODS

The PubMed database was searched to retrieve clinical studies that evaluated peri-implantitis-related healthcare interventions and were published between 2017 and 2021. A 4-level modified Oxford 2011 LOE tool was used to determine the LOE of these studies. Citation count and Altmetric Attention Scores (AAS) were derived from the Web of Science and Altmetric Explorer, respectively. Multivariate generalized estimation equation (GEE) analysis was conducted to explore relationships between the LOE and citation count, and between the LOE and AAS; the publication year was considered the grouping factor for adjusting for potential clustering effects.

RESULTS

Two hundred and thirty-five studies were considered eligible. The percentages by level from Level-1 to Level-4 were 9.8%, 35.7%, 28.9%, and 25.5%. Multivariable GEE analyses revealed that studies with higher LOE ratings had significantly greater citation counts (p = 0.008). However, no significant association (p = 0.872) was observed between the LOE and AAS.

CONCLUSIONS

From 2017 to 2021, more than 40% of studies published on peri-implantitis each year had high-LOE ratings. High-LOE studies showed a tendency to have greater scientific impact.

Artificial intelligence in orthodontics and orthognathic surgery: a bibliometric analysis of the 100 most-cited articles

BACKGROUND

The application of artificial intelligence (AI) in orthodontics and orthognathic surgery has gained significant attention in recent years. However, there is a lack of bibliometric reports that analyze the academic literature in this field to identify publishing and citation trends. By conducting an analysis of the top 100 most-cited articles on AI in orthodontics and orthognathic surgery, we aim to unveil popular research topics, key authors, institutions, countries, and journals in this area.

METHODS

A comprehensive search was conducted in the Web of Science (WOS) electronic database to identify the top 100 most-cited articles on AI in orthodontics and orthognathic surgery. Publication and citation data were obtained and further analyzed and visualized using R Biblioshiny. The key domains of the 100 articles were also identified.

RESULTS

The top 100 most-cited articles were published between 2005 and 2022, contributed by 458 authors, with an average citation count of 22.09. South Korea emerged as the leading contributor with the highest number of publications (28) and citations (595), followed by China (16, 373), and the United States (7, 248). Notably, six South Korean authors ranked among the top 10 contributors, and three South Korean institutions were listed as the most productive. International collaborations were predominantly observed between the United States, China, and South Korea. The main domains of the articles focused on automated imaging assessment (42%), aiding diagnosis and treatment planning (34%), and the assessment of growth and development (10%). Besides, a positive correlation was observed between the testing sample size and citation counts (P = 0.010), as well as between the time of publication and citation counts (P < 0.001).

CONCLUSIONS

The utilization of AI in orthodontics and orthognathic surgery has shown remarkable progress, particularly in the domains of imaging analysis, diagnosis and treatment planning, and growth and development assessment. This bibliometric analysis provides valuable insights into the top-cited articles and the trends of AI research in this field.

Level of evidence and characteristics of clinical studies published in leading prosthodontics journals

STATEMENT OF PROBLEM

Data on the level of evidence and the characteristics of studies published in peer-reviewed prosthodontic journals are lacking.

PURPOSE

The purpose of this study was to investigate the characteristics and level of evidence (LOE) scores of studies published in 3 leading peer-reviewed prosthodontic journals.

MATERIAL AND METHODS

Clinical studies published in the Journal of Prosthetic Dentistry (JPD), the Journal of Prosthodontics (JP), and the International Journal of Prosthodontics (IJP) in 2013 and 2020 were included in the analysis. Abstracts, letters to the editor, book reviews, and animal and laboratory studies were excluded from the investigation. For each study, design, type and LOE scores (Levels 1 to 5), publication year, impact factor (IF) of the journals, geographic origins of the first and corresponding authors, and funding status were recorded. Level 1 and Level 2 were defined as high evidence (HE), and Level 3, Level 4, and Level 5 were defined as low evidence (LE). Descriptive statistics and logistic regression analysis were performed (α=.05).

RESULTS

Among the 439 studies included in the analysis, the proportion of HE and LE studies was 14.1% and 85.9%, respectively. According to univariate and multivariate analysis results, year of publication (P=.010 and P=.029), geographic origin of the corresponding author (P<.001), and funding status (P<.001 and P=.002) were significantly associated with the LOE of a study. However, the journal IF was not associated with LOE (P=.328).

CONCLUSIONS

Although the number of HE studies in 3 leading prosthodontic journals has increased over time, the total number was still limited compared with LE studies. A further improvement in the overall LOE of clinical studies in prosthodontics is needed.

THE USE OF DENTAL PATIENT-REPORTED OUTCOMES AMONG RANDOMIZED CONTROLLED TRIALS IN ORTHODONTICS: A METHODOLOGICAL STUDY

OBJECTIVE

To identify and summarize the use and characteristics of dental patient-reported outcomes (dPROs) and dental patient-reported outcome measures (dPROMs) within randomized controlled trials (RCTs) published in 5 leading orthodontic journals.

METHODS

A manual search was conducted to identify intervention (therapeutic or preventive) related RCTs published in selected journals between 2015 and 2021. Two authors extracted the characteristics of each included trial, as well as all outcomes and outcome measures used in these trials independently and in duplicate. Thereafter, the use of dPROs and dPROMs was identified and summarized. We classified all dPROs into 2 general types (oral health-related quality of life [OHRQoL] and others) and dPROMs into 3 categories (single-item questionnaires, generic multiple-item questionnaires, and specific multiple-item questionnaires). We also identified whether these dPROMs assessed 4 dimensions of OHRQoL (Oral Function, Orofacial Pain, Orofacial Appearance, and Psychosocial Impact).

RESULTS

From 4631 examined articles, a total of 315 RCTs were included, of which 76 (24.1%) used dPROs and dPROMs. Eight different dPROs (OHRQoL, patients' satisfaction with treatment, difficulty, compliance, preference, efficacy, duration, and unwanted events) and 34 different dPROMs (including 13 single-item questionnaires, 7 generic multiple-item questionnaires, and 14 specific multiple-item questionnaires) were identified in these trials. OHRQoL was the most commonly used dPRO (n = 71; 93.4%), followed by patients' satisfaction with treatment (n = 10; 13.2%), patient-reported difficulty (n = 5; 6.6%), and patient-reported compliance (n = 4, 5.3%). The 4 most frequently used dPROMs were pain measured with 10 mm Visual Analogue Scale (n = 20; 24.1%), pain measured with Numerical Rating Scale (n = 11; 13.3%), the Feldmann's Questionnaire (2007) (n = 6; 7.2%), and the Oral Health Impact Profile 14 (n = 5; 6.0%).

CONCLUSION

Only about one-fourth of RCTs published in leading orthodontic journals can reflect patients' perspectives. OHRQoL was the most commonly used dPRO in these trials. Substantial heterogeneity exists among dPROMs used for OHRQoL assessment. Efforts are needed from researchers, reviewers, editors and other stakeholders to promote the wide and standardized use of dPROs in orthodontic research.

Bibliometric analysis of research publications in three major orthodontic journals during 2012–2021

Objectives:

This study conducted a comprehensive bibliometric analysis of articles published from 2012 to 2021 in three orthodontic journals: The American Journal of Orthodontics and Dentofacial Orthopedics (AJODO), The Angle Orthodontist (AO), and European Journal of Orthodontics (EJO).

Material and Methods:

Eligible articles published from 2012 to 2021 in AJODO, AO, and EJO were retrieved from the Web of Science Core Collection database and subsequently processed using CiteSpace software to generate their characteristics, including authorship, institution, geographic origin, keywords, and citation profiles.

Results:

The three orthodontic journals published 4001 articles from 370 institutions in 95 countries from 2012 to 2021. The AJODO published the most articles (45.5%) followed by AO (31.3%) and EJO (23.2%). The most prolific country was the United States (US), followed by Brazil, South Korea, China, and Turkey. The authors from the US were heavily engaged in international collaborations, especially with South Korea and Brazil. The country and institutions with the highest citation counts per publication were Italy and the University of Bern (Switzerland), respectively. Pandis N was the most prolific author, and Proffit W was the most-cited author in the 4001 publications. The keywords that emerged most frequently were “children” followed by “orthodontic treatment” and “malocclusion.” Four of the 10 most-cited articles were related to digital dental technology.

Conclusion:

This bibliometric analysis provides a complete picture of the research published in three major orthodontic journals over the past decade. It comprehensively analyzes the authorship, country of origin, institutions, keywords, and citation profiles of the articles.

Level of Evidence of Dental Research in Saudi Arabia (2000-2020)

Objectives

The level of evidence (LOE) of Saudi dental research from 2000 to 2020 was evaluated, and factors associated with the LOE were determined.

Methods

This study was a systematic review. PubMed, Web of Science, and Medline databases were utilized to retrieve available dental articles published in English between January 2000 and May 2020. The inclusion criteria consisted of clinical studies conducted in Saudi Arabia with at least one Saudi dental affiliation. The retrieved eligible articles were evaluated independently by two reviewers using a modified Oxford LOE scale. The LOE of the studies was compared between the last two decades.

Results

Of the 7237 articles identified, 1557 articles met the inclusion criteria. Approximately 78% of the published articles reported Level IV evidence. A higher trend toward Level I, II, and III publications has occurred in recent years (i.e., 2010-2020). However, no statistically significant difference existed in LOE proportions between the two decades. The presence of international collaboration and high journals' impact factor was significantly associated with a higher LOE.

Conclusion

Most published dental research studies were low LOE studies (i.e., Level IV). National and international collaboration is highly encouraged as this is a factor, according to our findings, that would be a positive addition toward publishing dental research of a higher LOE in Saudi Arabia.

The presence and characteristics of 'spin' among randomized controlled trial abstracts in orthodontics

OBJECTIVES

To identify the presence and characteristics of spin (using reporting strategies to distort study results and mislead readers) within randomized controlled trial (RCT) abstracts published in orthodontic journals, and to explore the association between spin and potentially related factors.

METHODS

A manual search was conducted to identify abstracts of RCTs with statistically non-significant primary outcomes published in five leading orthodontic journals between 2015 and 2020. Spin in the Results and Conclusions sections of each included abstract was evaluated and categorized according to pre-determined spin strategies. Logistic regression analyses were employed to explore the association between spin and relevant factors.

RESULTS

A total of 111 RCT abstracts were included, of which 69 (62.2 per cent) were identified with spin. In the Results section, 47 (42.3 per cent) abstracts had spin, and 'focusing on significant within-group comparison for primary outcomes' was the most frequent spin strategy. In the Conclusions section, 57 (51.4 per cent) abstracts presented spin, with the most common strategy being 'claiming equivalence or non-inferiority for statistically nonsignificant results'. According to multivariable logistic regression analysis, a significantly lower presence of spin was found in studies with international collaboration (odds ratio [OR]: 0.331, 95 per cent confidence interval [CI]: 0.120-0.912, P = 0.033) and trial registration (OR: 0.336, 95 per cent CI: 0.117-0.962, P = 0.042).

CONCLUSION

The prevalence of spin is high among RCT abstracts in orthodontics. Clinicians need to be aware of the definition and presence of spin. Concerted efforts are needed from researchers and other stakeholders to address this issue.

The reporting quality of split-mouth trials in orthodontics according to CONSORT guidelines: 2015-19

OBJECTIVES

To assess the reporting quality of split-mouth trials (SMTs) in orthodontic journals, and to identify factors associated with better reporting.

MATERIALS AND METHODS

Seven leading orthodontic journals were hand searched for SMTs published during 2015-19. The CONSORT 2010 guideline and CONSORT for within-person trial (WPT) extension were used to assess the trial reporting quality (TRQ) and WPT-specific reporting quality (WRQ) of included SMTs, respectively. A binary score (0 or 1) was given to each item of the guidelines, and total scores were calculated for TRQ (score range, 0-32) and WRQ (score range, 0-15). Univariable and multivariable linear regression analyses were performed to identify factors associated with TRQ and WRQ.

RESULTS

A total of 42 SMTs were included. The mean overall scores for TRQ and WRQ were 16.8 [standard deviation (SD) 7.1] and 5.6 (SD 2.3), respectively. Only 11 SMTs (26.2%) presented the rationale for using a split-mouth design. Key methodological items including random sequence generation (22/42, 52.4%), allocation concealment (9/42, 21.4%), and blinding (20/42, 47.6%) were poorly reported. Only six SMTs (14.3%) used a paired method for sample size calculation, and half (21/42, 50.0%) considered the dependent nature of data in statistical analysis. In multivariable analyses, higher TRQ and WRQ were both significantly associated with journal, reported use of CONSORT and funding status.

CONCLUSIONS

The reporting quality of SMTs in orthodontics has much room for improvement. Joint efforts from relevant stakeholders are needed to improve the reporting quality of SMTs and reduce relevant avoidable research waste.

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.

Spin in the abstracts of randomized controlled trials in periodontology and oral implantology: A cross-sectional analysis

OBJECTIVES

To investigate the presence and characteristics of spin (a distorted interpretation to make research findings seem favorable) in abstracts of randomized controlled trials (RCTs) in periodontology and oral implantology, and to explore its associated factors and influence on the subsequent literature.

MATERIALS AND METHODS

PubMed was searched to identify recent RCTs in periodontology and oral implantology, whose primary outcome was non-significant. Spin in abstracts was assessed and categorized according to pre-determined spin strategies. The associations between study characteristics and the presence / severity of spin were analyzed using multivariable logistic regressions.

RESULTS

196 abstracts were included, 137 (69.9%) of which had spin. 57 (29.1%) abstracts had spin in the Results Section, 126 (64.3%) had spin in the Conclusion Section. The main spin strategies in the Results and Conclusion Sections were focusing on secondary outcomes (16.3%) and focusing on within-group comparisons (28.6%), respectively. The presence of spin was associated with number of centers (OR=0.28, 95% CI: 0.11-0.73; p=0.009) while its severity was associated with topic (OR=0.24, 95% CI: 0.08-0.70; p=0.009).

CONCLUSIONS

The frequency of spin is relatively high among published RCT abstracts in periodontology and oral implantology. Findings reported in these abstracts need to be interpreted with caution.

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.