Text and Data Mining valid from 2019-08-05
Received: 23 May 2018
Accepted: 15 July 2019
First Online: 5 August 2019
Ethics approval and consent to participate
: This study involved only analysis of data from published scientific literature; we did not collect any primary data.
: Not applicable.
: Livia Puljak is Section Editor of BMC Medical Research Methodology; however, she was not involved in any way in handling and decision-making regarding this manuscript. Other authors declare that they have no competing interests.