Correction: Relationship between serum osteocalcin/undercarboxylated osteocalcin and type 2 diabetes: a systematic review/meta-analysis study protocol ======================================================================================================================================================= Liu Y, Liu X, R Lewis J, *et al*. Relationship between serum osteocalcin/undercarboxylated osteocalcin and type 2 diabetes: a systematic review/meta-analysis study protocol. *BMJ Open* 2019;9:e023918. doi: 10.1136/bmjopen-2018-023918 The affiliations for the third author, Joshua R Lewis, were incomplete in the previous version of this manuscript. The correct and updated affiliations of the authors are as follows: Yihui Liu,1,2 Xiaoying Liu,2 Joshua R Lewis,1,2,3,4 Kaye Brock,5 Tara C Brennan-Speranza,5 Armando Teixeira-Pinto1,2 1Centre for Kidney Research, The Children’s Hospital, Westmead, New South Wales, Australia 2Biostatistics, School Public Health, Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, Australia 3School of Medicine, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, Australia 4School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia 5School of Medical Sciences, University of Sydney, Camperdown, New South Wales, Australia This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: [http://creativecommons.org/licenses/by-nc/4.0/](http://creativecommons.org/licenses/by-nc/4.0/).