Analysis of abstracts presented at the prosthodontic research section of IADR General Sessions 2004-2005: demographics, publication rates, and factors contributing to publication

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.

Conference abstracts-what gets published, when, and from where?

BACKGROUND

Scientific meetings provide a platform for disseminating new research. Abstracts presented at these meetings are frequently published as full-length papers in peer-reviewed journals. The primary aims of this study were to determine the publication rate and time to publication of abstracts presented at the European Orthodontic Society (EOS) and World Federation of Orthodontists (WFO) congresses in 2015. The secondary aim was to identify factors predicting the publication of abstracts.

METHODS

The congress abstracts were identified from the congress report or organizers. Systematic searches of the PubMed, Google Scholar, Scopus, and Web of Science databases were performed to identify papers based on the abstracts identified. Abstract titles, first and last authors' last name, and keywords were used to identify whether an abstract resulted in a publication. Abstracts published as full-length articles were then analyzed.

RESULTS

In total, 208 abstracts were identified, of which 46.6% were published as full-length articles. The median time to publication was 17 months after the EOS congress, and 8.5 months after the WFO congress. Abstracts presented orally were more likely to be published than those presented as posters. Abstracts from Europe were more likely to result in publication. The subject and setting of the study were poor predictors of publication.

CONCLUSIONS

Less than half of the abstracts presented at the EOS and WFO congresses in 2015 led to full publication in a peer-reviewed journal. The mode of presentation and the region of origin of the research were good predictors of publication.

Publication rate of abstracts from presentations at the British Orthodontic Conference 2009–2014

Objective:

The primary objective of this study was to investigate the publication rate of scientific abstracts presented at the British Orthodontic Conference 2009–2014. Predictors of full-text publications after presentation of abstracts were explored.

Design:

Cross-sectional study.

Materials and methods:

Details of abstracts were retrieved from the conference programmes. Abstracts were screened and full-text publications identified by a single author with discrepancies discussed. Two electronic databases were searched to identify full-text publication of abstracts presented at the British Orthodontic Conference during 2009–2014. Study characteristics were recorded in a prespecified data collection sheet. Descriptive and correlation statistics were calculated. Multivariable Cox regression modelling was implemented in order to assess the effect of predictors on the instance of probability of publication.

Results:

A total of 225 abstracts (148 poster presentations and 77 oral presentations) were identified. Observational studies were frequent (60%) and significant results were reported in 38.7% of abstracts. The rate of full-text publication after abstract presentation was 46.2% with a mean time to publication of 18.3 ± 18.7 months. Authors based at both university and hospitals (Hazard ratio: 2.63, 95% confidence interval [CI] 1.26–5.47, P=0.01) had a higher instant probability of publication compared to university only, whereas diagnostic studies (Hazard ratio: 0.18, 95% CI 0.04–0.74, P=0.02) had lower instant probability of publication compared to systematic reviews.

Conclusion:

Over 50% of study abstracts presented at the British Orthodontic Conference during 2009–2014 remain unpublished. Author affiliation and study type appear to influence full text publication. In order to reduce publication bias within the literature, publication of full-text articles by authors of presented abstracts is encouraged.

Abstracts presented at the European Association for Osseointegration (EAO) Congresses: Publication fate and discrepancies with full-length articles

OBJECTIVES

To investigate the full publication proportion (FPP) of abstracts presented at the 2010 and 2011 EAO Congresses, analyse the discrepancies between abstracts and their full publications, and explore potential predictors of FPP and discrepancies.

METHODS

Abstracts presented at the 2010 and 2011 EAO Congresses were retrieved. Associated full publications were identified by searching PubMed, Embase and Google Scholar. Discrepancies between abstracts and full publications were identified, classified and evaluated using a discrepancy score. The Kaplan-Meier survival analysis was used to describe cumulative FPP over time. Predictors for FPP and the discrepancy score were analysed using cox regression modelling and a linear regression model, respectively.

RESULTS

850 abstracts were included. The overall FPP was 36.4% with a median time lapse of 12 months. Higher FPP were significantly associated with oral presentation (HR=2.33; 95% CI: 1.68 to 3.22; p<0.001), multiple affiliations (HR =1.32; 95% CI: 1.00 to 1.73; p=0.048) and presence of statistical tests (HR =1.78; 95% CI: 1.36 to 2.32; p<0.001). 91.3% pairs had at least one minor change from the abstract and 70.9% had at least one major change. Greater discrepancy score was significantly associated with longer time lapse (B=0.06; 95% CI: 0.04 to 0.08; p<0.001) and being clinical research (B=1.30; 95% CI: 0.52 to 2.08; p=0.001).

CONCLUSIONS

Thirty-six percent of abstracts presented at the EAO Congresses were published. Among these, more than two-thirds showed at least one major change in their full publications. Abstracts presented in oral implantology conferences should not be relied upon to inform practice.

Analysis of conference abstracts of prosthodontic randomised-controlled trials presented at IADR general sessions (2002-2015): a cross-sectional study of the relationship between demographic characteristics, reporting quality and final publication

OBJECTIVES

To analyse the relationship between demographic characteristics, reporting quality and final publication rate of conference abstracts of prosthodontic randomised-controlled trials (RCTs) presented at International Association for Dental Research (IADR) general sessions (2002-2015).

DESIGN

A cross-sectional study on conference abstracts.

METHODS

Conference abstracts of prosthodontic RCTs presented at IADR general sessions (2002-2015) were obtained. Literature search was performed in multiple databases to confirm the final publication status of conference abstracts. Two investigators independently extracted the data including conference date, origin, presentation type, exact p value, number of centres, institution type, overall conclusion, subspecialty, publication time and journal. The reporting quality of abstracts was assessed by two investigators according to the Consolidated Standards of Reporting Trials statement. The relationship between demographic characteristics, reporting quality and final publication was analysed by χ² test.

SETTING, PARTICIPANTS AND INTERVENTIONS

Not applicable.

PRIMARY AND SECONDARY OUTCOME MEASURES

Final publication rate, demographic characteristics and reporting quality of conference abstracts of prosthodontic RCTs presented at IADR general sessions (2002-2015).

RESULTS

Of the 340 prosthodontic RCT abstracts, 43.24% were published. The mean time to final publication was 22.86 months. Europe contributed the most number of abstracts but Asia and Australia had the highest publication rate. Oral presentation, multicentre trial and complete denture and overdenture subspecialty were associated with a higher publication rate. Reporting quality of eligibility criteria of participants, random assignment and primary outcome results for each group correlated with a higher final publication rate.

CONCLUSIONS

Over half of conference abstracts of prosthodontic RCTs presented at IADR general sessions (2002-2015) were unpublished. Oral presentation and multiple centres were associated with higher publication rates. Abstracts' reporting quality addressing participant recruitment, assignment and primary results correlated with trials' validity and applicability. Conference attendees may refer to this research to identify valid and applicable prosthodontic trials but should treat and apply results cautiously.

Full publication of results initially presented in abstracts

BACKGROUND

Abstracts of presentations at scientific meetings are usually available only in conference proceedings. If subsequent full publication of results reported in these abstracts is based on the magnitude or direction of the results, publication bias may result. Publication bias creates problems for those conducting systematic reviews or relying on the published literature for evidence about health and social care.

OBJECTIVES

To systematically review reports of studies that have examined the proportion of meeting abstracts and other summaries that are subsequently published in full, the time between meeting presentation and full publication, and factors associated with full publication.

SEARCH METHODS

We searched MEDLINE, Embase, the Cochrane Library, Science Citation Index, reference lists, and author files. The most recent search was done in February 2016 for this substantial update to our earlier Cochrane Methodology Review (published in 2007).

SELECTION CRITERIA

We included reports of methodology research that examined the proportion of biomedical results initially presented as abstracts or in summary form that were subsequently published. Searches for full publications had to be at least two years after meeting presentation.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data and assessed risk of bias. We calculated the proportion of abstracts published in full using a random-effects model. Dichotomous variables were analyzed using risk ratio (RR), with multivariable models taking into account various characteristics of the reports. We assessed time to publication using Kaplan-Meier survival analyses.

MAIN RESULTS

Combining data from 425 reports (307,028 abstracts) resulted in an overall full publication proportion of 37.3% (95% confidence interval (CI), 35.3% to 39.3%) with varying lengths of follow-up. This is significantly lower than that found in our 2007 review (44.5%. 95% CI, 43.9% to 45.1%). Using a survival analyses to estimate the proportion of abstracts that would be published in full by 10 years produced proportions of 46.4% for all studies; 68.7% for randomized and controlled trials and 44.9% for other studies. Three hundred and fifty-three reports were at high risk of bias on one or more items, but only 32 reports were considered at high risk of bias overall.Forty-five reports (15,783 abstracts) with 'positive' results (defined as any 'significant' result) showed an association with full publication (RR = 1.31; 95% CI 1.23 to 1.40), as did 'positive' results defined as a result favoring the experimental treatment (RR =1.17; 95% CI 1.07 to 1.28) in 34 reports (8794 abstracts). Results emanating from randomized or controlled trials showed the same pattern for both definitions (RR = 1.21; 95% CI 1.10 to 1.32 (15 reports and 2616 abstracts) and RR = 1.17; 95% CI, 1.04 to 1.32 (13 reports and 2307 abstracts), respectively.Other factors associated with full publication include oral presentation (RR = 1.46; 95% CI 1.40 to 1.52; studied in 143 reports with 115,910 abstracts); acceptance for meeting presentation (RR = 1.65; 95% CI 1.48 to 1.85; 22 reports with 22,319 abstracts); randomized trial design (RR = 1.51; 95% CI 1.36 to 1.67; 47 reports with 28,928 abstracts); and basic research (RR = 0.78; 95% CI 0.74 to 0.82; 92 reports with 97,372 abstracts). Abstracts originating at an academic setting were associated with full publication (RR = 1.60; 95% CI 1.34 to 1.92; 34 reports with 16,913 abstracts), as were those considered to be of higher quality (RR = 1.46; 95% CI 1.23 to 1.73; 12 reports with 3364 abstracts), or having high impact (RR = 1.60; 95% CI 1.41 to 1.82; 11 reports with 6982 abstracts). Sensitivity analyses excluding reports that were abstracts themselves or classified as having a high risk of bias did not change these findings in any important way.In considering the reports of the methodology research that we included in this review, we found that reports published in English or from a native English-speaking country found significantly higher proportions of studies published in full, but that there was no association with year of report publication. The findings correspond to a proportion of abstracts published in full of 31.9% for all reports, 40.5% for reports in English, 42.9% for reports from native English-speaking countries, and 52.2% for both these covariates combined.

AUTHORS' CONCLUSIONS

More than half of results from abstracts, and almost a third of randomized trial results initially presented as abstracts fail to be published in full and this problem does not appear to be decreasing over time. Publication bias is present in that 'positive' results were more frequently published than 'not positive' results. Reports of methodology research written in English showed that a higher proportion of abstracts had been published in full, as did those from native English-speaking countries, suggesting that studies from non-native English-speaking countries may be underrepresented in the scientific literature. After the considerable work involved in adding in the more than 300 additional studies found by the February 2016 searches, we chose not to update the search again because additional searches are unlikely to change these overall conclusions in any important way.

A descriptive analysis of abstracts presented at the Turkish National Cardiology Congresses between 2011 and 2015

OBJECTIVE

The aim of this study was to investigate the scientific publication performance of the abstracts presented at the annual Turkish National Cardiology Congress (TNCC) between 2011 and 2015 and to analyze the variables associated with publication.

METHODS

The accepted abstracts of five congresses (2011-2015) were screened using the title and names of all authors in English via PubMed and Google Scholar databases. The parameters recorded included presentation type, publication rate, time to publication, affiliated institution, journal name and average impact factor, and average citation number per year for each publication.

RESULTS

A total of 2897 abstracts (966 oral presentations and 1931 poster presentations) were accepted in five meetings and 23.4% (n=680) of these were published in national or international peer-reviewed journals. Of the published articles, 32.6% (n=222) were oral presentations and 67.4% (n=458) were poster presentations. The mean time to publication of oral and poster presentations were similar [9 (0-58) vs. 8 (0-62) months, p = 0.150]. According to the type of institution, university hospitals had the highest ratio of publication (58.6%) (p<0.001). All publications were published in 148 journals from 37 different countries. The average citation number of publications was significantly higher than the average impact factor of the journals [1.4 (0-30.1) vs. 1.29 (0.11-19.8), p<0.001].

CONCLUSION

Compared with other national-based literature in other medical fields, the overall publication rate was found to be similar while the time to publication was shorter. The significant difference between citation number and impact factor may be interpreted as positive indicator in terms of high level scientific value for cardiology publications presented in the TNCC.

Full text publication rates of research abstracts presented at the European Society of Endodontology (ESE) Congresses in the last 20 years

AIM

To evaluate the full-text publication rates of scientific research abstracts presented at the European Society of Endodontology (ESE) Congresses held between 1993 and 2013 (a total of 11 occasions) and to determine factors associated with the manuscripts.

METHODOLOGY

An electronic database search was conducted from January 2015 to December 2016 to identify full text English written publications of the research abstracts presented at the last 11 ESE Biennial Congresses from 1993 to 2013. For each occasion, research abstract information were retrieved from the International Endodontic Journal (IEJ) through the official website of the ESE and the following parameters for each abstract presentation were recorded: Year of presentation, first author's affiliation, geographic origin, and type of study. Following full-text article identification, additional information was recorded such as: Year and journal of publication, elapsed time until full publication and number of authors per presentation and publication.

RESULTS

A total of 1165 research abstracts were presented, of which 401 (34.4%) were finally published as full-length articles. Overall 235 articles (58.6%) were published either in the International Endodontic Journal (IEJ, 35.7%) or Journal of Endodontics (JOE, 22.9%). The mean time between abstract presentation and full-text publication was 18.95 months. Munich (2001) had the highest publication rate (44%) whereas Lisbon (2013) had the highest number of published articles (77). Turkey was the country with the highest number of published abstracts (56). However, the Netherlands was the country with the highest number of publications related to the number of presentations (21/26) (80.7%). Differences in authorship between presentation and full publication were found in 179 (44.6%) articles.

CONCLUSIONS

A substantial number of research abstracts presented at ESE congresses were not published in peer reviewed journals. Authors prefer to publish their research papers in international journals with high impact factor. This article is protected by copyright. All rights reserved.

Thirty percent of abstracts presented at dental conferences are published in full: a systematic review

OBJECTIVES

To review the publication fate of abstracts presented at dental conferences and investigate the association between full publication proportion (FPP) and abstract characteristics, conference characteristics, and methodological quality of primary studies.

STUDY DESIGN AND SETTING

PubMed, EMBASE, and Google Scholar were searched up to November 2014 for studies that reported at least one FPP of abstracts presented at dental conferences, with a follow-up length of no less than 48 months.

RESULTS

Sixteen studies involving 10,365 abstracts presented at 52 conferences were included. The pooled FPP was 29.62% (95% confidence interval: 22.90%, 36.81%) for all presented abstracts and 51.97% (95% confidence interval: 43.19%, 60.70%) for randomized controlled trial abstracts. Abstract characteristics significantly associated with higher FPP included reporting of statistical analysis (P < 0.001), oral presentation (P < 0.001), basic science research (P = 0.047), and reporting of financial support (P = 0.009). Abstracts with positive (P = 0.29) or statistically significant results (P = 0.33) were not published more often than negative or nonsignificant results, respectively. In multivariable meta-regression analysis, conferences held in Asia (P < 0.001) and at a continental rather than national level (P < 0.001) were significantly associated with higher FPP.

CONCLUSIONS

Less than one-third of abstracts presented at dental conferences were published in full more than 4 years after conference presentation.

Publication rate of studies presented at veterinary anaesthesia specialty meetings during the years 2003-2008

OBJECTIVE

To assess publication rates, factors predicting publication, and discrepancies between conference abstracts and subsequent full-text publications of abstracts from the veterinary meetings of the American College of Veterinary Anesthesiologists and the Association of Veterinary Anaesthetists from 2003 to 2008.

STUDY DESIGN

Retrospective cohort study.

METHODS

A total of 607 abstracts were identified and a database search (Scopus, PubMed, CAB) was conducted to identify matching publications. Authors of nonmatching abstracts were contacted to participate in a confidential online survey. Risk ratios were used to assess factors predicting publication and these were tested for significance (p < 0.05) using Fisher's exact test.

RESULTS

The overall publication rate was 63.3% and the mean (± SD) time to publication was 25 ± 19 months. Factors significantly associated with subsequent full publication (i.e. publication of a full manuscript in a peer-reviewed journal) were continent of origin (North America), study design (experimental studies), specialty (analgesia) and the presence of a source of funding. The principal reasons why studies remained unpublished were lack of time and responsibility lying with co-authors. Minor changes compared with the original abstract were found in 71.6% of all publications. Major changes were noted in 34.6% and the outcome of the study changed in 7.6%.

CONCLUSIONS AND CLINICAL RELEVANCE

These data suggest that some of the abstracts reported preliminary findings. Therefore, caution is warranted when quoting abstracts as references in scientific publications. To date, major veterinary journals have not issued recommendations in their author guidelines addressing the use of abstracts as a reference. The authors propose the inclusion of such a statement in author guidelines.

What is the fate of scientific abstracts? The publication rates of abstracts presented at the 7th National Congress of Gynecology and Obstetrics

Objective:

Oral and poster presentations held at national and international congresses are recognized as valuable tools for sharing current scientific data and experience among physicians. However, a large proportion of these works fail to be published in scientific journals. We have designed a study to identify the publication rate of presentations held at the 7^th National Congress of Obstetrics and Gynecology in 2009.

Materials and Methods:

A systematic search of databases was performed using author names and key words from the abstract title to locate publications in peer-reviewed journals corresponding to the presentations held at the 7^th National Congress of Obstetrics and Gynecology. Information regarding mode of presentation, topic, type of affiliation, name and impact factor of the scientific journal, change in author names and time elapsed between presentation and publication were recorded and analyzed statistically.

Results:

Of 243 abstracts that were presented at the congress, 45 papers (18.5%) were published in international peer-reviewed journals, whereas 39 (16%) were published in national journals. The mean time to publication was 17±2 months for international and 11±4 months for national journals (p=0.102). The international publication rate of oral presentations was significantly higher than that of poster presentations (50% vs. 16.2%; p<0.03). The manuscripts were published in a total of 21 journals, with four journals accounting for 49% of the publications. The comparison of the publication rates of the universities with other institutions has yielded no significant difference.

Conclusion:

Alltough a significant proportion of the abstracts presented in the 7^th National Gynecology and Obstetrics Congress have been succesfully converted to publication overall, only a limited percentage of all abstracts have been published in international peer-reviewed journals. The relatively higher conversion to international publication rate of the oral presentations show that they are of higher interest and clinical relevance.

Full-text publication of abstracts presented at European Orthodontic Society congresses

INTRODUCTION

Empirical evidence has indicated that only a subsample of studies conducted reach full-text publication and this phenomenon has become known as publication bias. A form of publication bias is the selectively delayed full publication of conference abstracts. The objective of this article was to examine the publication status of oral abstracts and poster-presentation abstracts, included in the scientific program of the 82nd and 83rd European Orthodontic Society (EOS) congresses, held in 2006 and 2007, and to identify factors associated with full-length publication.

METHODS

A systematic search of PubMed and Google Scholar databases was performed in April 2013 using author names and keywords from the abstract title to locate abstract and full-article publications. Information regarding mode of presentation, type of affiliation, geographical origin, statistical results, and publication details were collected and analyzed using univariable and multivariable logistic regression.

RESULTS

Approximately 51 per cent of the EOS 2006 and 55 per cent of the EOS 2007 abstracts appeared in print more than 5 years post congress. A mean period of 1.32 years elapsed between conference and publication date. Mode of presentation (oral or poster), use of statistical analysis, and research subject area were significant predictors for publication success.

LIMITATIONS

Inherent discrepancies of abstract reporting, mainly related to presentation of preliminary results and incomplete description of methods, may be considered in analogous studies.

CONCLUSIONS

On average 52.2 per cent of the abstracts presented at the two EOS conferences reached full publication. Abstracts presented orally, including statistical analysis, were more likely to get published.

Discrepancies between Abstracts Presented at International Association for Dental Research Annual Sessions from 2004 to 2005 and Full-Text Publication

Purpose. The purpose of this study was to evaluate the discrepancies between abstracts presented at the IADR meeting (2004-2005) and their full-text publication. Material and Methods. Abstracts from the Prosthodontic Section of IADR meeting were obtained. The following information was collected: abstract title, number of authors, study design, statistical analysis, outcome, and funding source. PubMed was used to identify the full-text publication of the abstracts. The discrepancies between the abstract and the full-text publication were examined, categorized as major and minor discrepancies, and quantified. The data were collected and analyzed using descriptive analysis. Frequency and percentage of major and minor discrepancies were calculated. Results. A total of 109 (95.6%) articles showed changes from their abstracts. Seventy-four (65.0%) and 105 (92.0%) publications had at least one major and one minor discrepancies, respectively. Minor discrepancies were more prevalent (92.0%) than major discrepancies (65.0%). The most common minor discrepancy was observed in the title (80.7%), and most common major discrepancies were seen in results (48.2%). Conclusion. Minor discrepancies were more prevalent than major discrepancies. The data presented in this study may be useful to establish a more comprehensive structured abstract requirement for future meetings.