The major findings of this work are: Poster abstract reporting quality at the American Burn Association annual meeting of 2000 and 2008 is not necessarily inferior to oral abstracts as far as study design and reporting quality of clinical trials is concerned. The primary hypothesis has to be rejected. However, endorsement for the comprehensive use of the CONSORT and STROBE criteria might further increase the quality of reporting ABA conference abstracts in the future.
These observations should be discussed in detail. This is the first reporting quality evaluation and comparing study in the field of burn surgery. Evidence-based criteria such as study design and measure of reporting quality like the CONSORT and the STROBE score are useful for abstractcomparison. The increased assessment of study quality has led to the development of numerous scales and checklists [8]. In the last years, CONSORT and STROBE checklists were used more frequently to analyse the reporting quality in published studies [9, 10]. Additionally, calculating a scale provides readers a quantitative index of trial quality by assigning a numeric scores to each item present, contributing to an overall total.
In the ABA annual meeting the oral and poster abstract reporting quality revealed no differences, but the number of presented RCTs was still very limited with 5% at best. These results are consistent with other studies especially in the surgical field [11, 12]. A tenyear analysis of publications in Plastic and Reconstructive Surgery, Annals of Plastic Surgery and Aesthetic Surgery Journal revealed a RCT publication rate of 3.2% [13]. Major reasons for the lack of RCTs are the complexity of study design associated with intensive patient care, expenditure of time and high costs. And also, ethical considerations in interventions are a challange in realizing RCTs. However, a surgical RCT enables optimal properties to minimize bias in the estimation of the treatment effect which can otherwise easily be underestimated or exaggerated. RCTs are widely acknowledged as the gold standard for the assessment of medical interventions [14–16] and therefore the number of RCTs is hopefully to improve in the future in burn surgery, too [17].
As far as the minimum requirements for future conference abstracts are concerned, it is rather difficult to propose detailed suggestions. Following the CONSORT and STROBE criteria it would be crucial in our view to clearly note the study design, details on recruitment of participants, study size randomization, quantitative variables, main outcome, harms and especially potential funding in the abstract form to improve reporting quality. These items would allow the abstract reader to assess the conference abstract in a more comprehensive way. However, limited available space has to be considered in this regard. Depending on conference and journal requirements word count is usually limited to 250 to 300 words for conference abstracts. Therefore the abstract format is often times strictly controlled with background, methods, results, and conclusions. Thus, investigators are influenced and guided by these requirements. In addition, the CONSORT group has calculated that within 250 to 300 words, all 17 items of the CONSORT abstract recommendations are met.
In several studies, it was reported that the information given for trials in conference proceedings is far from being optimal [18, 19]. Clear, transparent and accurate reporting or research is important because it enables readers to understand what was done and to acess the applicability and relevance of the findings. The extension of CONSORT aims to improve the reporting in randomized-control trials. However, we believe, beyond the primary scope of CONSORT for RCT and STROBE for observational studies, that in general, the abstracts reporting quality will benefit from the implementation of standardized criteria to improve the reporting quality, both in the abstract as well as in a potential subsequent full manuscript.
Limitations
Several limitations of our study should be noted. First, we evaluated the quality of reporting, which is not the same as the methodologic quality of the study. It is possible that a poorly reported study is well designed and executed, and a well-reported one may have several shortcomings. However, empirical evidence exists that indicates poorly reported studies are associated with larger estimates of intervention effect, i.e. poor reporting reflects poor methodology, which in turn is associated with biased results [20].
Second, given the suggestions of the conference organizing committee regarding the abstract format and the restricted word count, it has to take into account that the implementation of a more comprehensive reporting in abstracts might be hampered by the abstract requirements stated by the conference organizers. Also, submission and selection process of journals, including author request of presentation (oral, poster) could influence the type of presentation. And also it should be acknowledged that abstract are submitted and judged by category. Therefore request of presentation by author or categorisation by journal could be a potential confounder in this study.
Furthermore, we analysed only studies of evidence level 1++ to 2- according to the Scottish Intercollegiate Guidelines Network (SIGN). Because of the low evidence, experimental studies, new techniques and describing new concepts were excluded from the analysis. In this context, laboratory studies and animal studies were classified as experimental studies. Furthermore, it is possible that the analysed study designs in abstracts are misinterpertated. In addition, the CONSORT criteria were suggested primarily for randomized-controlled trials which took only about 2-7% of study designs in conference abstracts. We also acknowledge that STROBE is currently limited to three main observational study designs: cohort, case-control, and cross-sectional studies. Furthermore the STROBE criteria were not primary designed for abstracts. But no other better instrument was available and because of its specificity for observational studies, we think it was the best way to evaluate the reporting quality. While no such statements or checklists for experimental or other study designs were available, we applied the Timmer instrument for abstract quality in addition to the aforementioned measures. The Timmer instrument is a valid quality assessment tool for conference abstracts and comparing these three instruments for analysing the abstract quality leads to an increased internal validity and reliability of the study. In addition, it should be kept in mind that in this study misclassification in approaching to CONSORT and STROBE criteria could occur [21]. To minimize this effect, criteria for reporting in conference abstracts were analysed by two researchers independently. Finally, we compared just two different years, with two different sets of abstract. This limited amout of sampling gives some limitation in external validity of these trials. Therefore further analysis of more data, especially multiple year comparisons and comparing trends over time, is needed.