RT Journal Article SR Electronic T1 Editors’ Commentary: The Effect of Vitamin D Deficiency on Outcomes of Patients Undergoing Elective Spinal Fusion Surgery: A Systematic Review and Meta-Analysis by Khalooeifard et al JF International Journal of Spine Surgery JO Int J Spine Surg FD International Society for the Advancement of Spine Surgery SP 2 OP 3 DO 10.14444/8170 VO 16 IS 1 A1 Kai-Uwe Lewandrowski A1 Morgan P. Lorio YR 2022 UL http://ijssurgery.com//content/16/1/2.abstract AB