Do dental research journals publish only positive results? A retrospective assessment of publication bias

Factors influencing the impact of randomized clinical trials on dental implants: A bibliometric analysis

OBJECTIVE

To analyze bibliometrics, characteristics, and the risk of bias of randomized controlled trials (RCTs) on dental implants published in six high-impact factor journals and to identify factors contributing to citation number.

MATERIALS AND METHODS

A systematic electronic search was conducted in four databases (PubMed, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials) to identify RCTs on dental implants published in six dental journals between 2016 and 2017. Twenty-five bibliometric variables and paper characteristics were extracted to evaluate their contribution to the citation count. Risk of bias analysis was performed using the RoB2 tool. Negative binomial regression was used to examine the effects of predictor variables on the Citation count. Significance level was set to 5%.

RESULTS

A total of 150 RCTs included received a cumulative citation count of 3452 until July 2022. In the negative binomial regression analysis, open-access RCTs exhibited 60% more citations, and RCTs that presented statistical significance received 46% more citations. Conversely, first author affiliations from Africa, Asia and Oceania continents showed 49% fewer citations than publications from Europe. Regarding the risk of bias, 73.3% of the RCTs had some concerns, while 26% were deemed to have a high risk of bias. Only one RCT (0.07%) showed a low risk of bias.

CONCLUSION

Within the limitation of the study, factors such as open access, statistically significant results, and country influence the number of citations received by the RCTs on dental implants.

Transparency in clinical trials: Adding value to paediatric dental research

BACKGROUND

Even though considered as studies with high methodological power, many RCTs in paediatric dentistry do not have essential quality items in their design, development, and report, making results' reliability questionable, replication challenging to conduct, wasting time, money, and efforts, and even exposing the participants to research for no benefit.

AIM

We addressed the main topics related to transparency in clinical research, with an emphasis in paediatric dentistry.

DESIGN

We searched for all controlled clinical trials published from January 2019 up to July 2020 in the three paediatric dentistry journals with high journal Impact Factor, indexed on Medline. These papers were assessed for transparency according to Open Science practices and regarding reporting accuracy using some items required by CONSORT.

RESULTS

53.6% of the studies declared registration, 75% had sample size calculation, 98.2% reported randomisation, and from those, 65.4% explained the randomisation method. Besides that, no study shared their data, and 6.8% were published in open access format.

CONCLUSIONS

Unfortunately, a large proportion of RCTs in paediatric dental research show a lack of transparency and reproducibility.