What is new?
Registration in an International Clinical Trial Registry was associated with improved reporting. Further efforts to enhance randomized controlled trial (RCT) registration could contribute to this improvement. Reporting of varied Consolidated Standards of Reporting Trials (CONSORT) items remains suboptimal, and there is still significant need for improvement in high ranked journals. As suggested by the International Committee of Medical Journal Editors (ICMJE), all journals publishing RCTs should require prospective trial registration identification number to improve the quality of reporting.
The Consolidated Standards of Reporting Trials (CONSORT) statement was first developed in 1996 and updated in 2001 [1], [2] with the aim of improving the reporting of randomized controlled trial (RCT) as well as enabling readers to understand its conduct and to estimate the validity of its results [3]. Extensions of the CONSORT statement have been developed to provide guidance for RCTs with specific designs, data, and interventions. Editorial groups, such as the Council of Science Editors, the International Committee of Medical Journal Editors (ICMJE), and the World Association of Medical Editors (WAME) as well as more than 150 medical, clinical, and psychological journals have endorsed CONSORT. It requires trial lists and journal articles to follow a checklist of 22 items and a four-stage flow diagram along with a brief descriptive text. The checklist items focus on reporting how the trial was designed, analyzed, and interpreted and the flow diagram displays the progress of all participants through the trial [4].
Since the publication of CONSORT, a number of studies have evaluated its effectiveness for improving the quality of reporting. A systematic review to determine whether the adoption of the CONSORT checklist was associated with the improvement in the quality of RCTs found that CONSORT adopters had reported significantly better the method of sequence generation (risk ratio [RR]: 1.67; 95% confidence interval [CI]: 1.19–2.33), allocation concealment (RR: 1.66; 95% CI: 1.37–2.00), and overall number of CONSORT items than nonadopters (standardized mean difference [SMD]: 0.83; 95% CI: 0.46–1.19) [3]. When evaluating CONSORT-adopting journals before and after the publication of CONSORT, description of the method of sequence generation (RR: 2.78; 95% CI: 1.78–4.33), participant flow (RR: 8.06; 95% CI: 4.10–15.83), and total CONSORT items (SMD: 3.67 items; 95% CI: 2.09–5.25) were improved after adoption of CONSORT by the journal.
Varied publications reported the assessment of the quality of RCT by conducting cross-sectional or observational studies to examine the extent to which they adhere to the CONSORT statement [5], [6], [7], [8], [9], [10]. Most studies found that although reporting some CONSORT recommendations have improved over time, the reporting of several essential recommendations remains suboptimal and in need for significant improvement [5], [6], [7], [8], [9], [10], [11], [12].
The impact factor (IF) is a measure of the citations of the science journals; it is used as an alternative to estimate the importance of a journal [13], [14]. Although, it could be assumed that the highest ranked journal may have better quality reporting methods, but at the best of our knowledge, there are no studies evaluating the quality of reporting in this specific journal subset.
The number of registries and registered clinical trials has been increasing dramatically since 2004, after the requirement for registration at inception in a public register was introduced by several medical journals. Published protocols are a particularly valuable source of information when they are fully available. However, few protocols are currently publicly available and information is not standardized and is often found in the form of long essay documents, which hamper the search for the information needed. Currently, the main source of essential protocol information can be found in trial registries, which aim at providing the essential information as defined by the World Health Organization (WHO) standards. There is general agreement about the minimum protocol information that should be registered for a trial, as defined by the 20-item of the WHO Registration Data Set [15], [16], [17], [18].
Our study aimed to evaluate the reporting quality of key methodological items of RCTs of the 55 highest ranked journals. We also aim to compare the reporting quality between journals that have reported registration in an International Clinical Trials Registry and those that have not.