Received: 7 May 2019
Accepted: 24 February 2020
First Online: 17 March 2020
Ethics approval and consent to participate
: Not applicable. This study did not include any participants; we analyzed publicly available bibliographic information about published research articles.
: Not applicable.
: Livia Puljak is section editor at the BMC Medical Research Methodology. Antonia Jelicic Kadic is Associate Editor of the BMC Medical Research Methodology. However, two of them were not involved in any way in handling of this manuscript. Other authors have nothing to declare regarding potential competing interests.