Confounding variables in future studies assessing relationship between paraspinal muscles and low back pain

Affiliations

• ¹ Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA. Electronic address: vwo569@mail.harvard.edu.
• ² Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
• ³ Department of Anesthesia and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA.
• ⁴ Department of Anesthesia, Critical Care and Pain Medicine, Division of Pain, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
• ⁵ Department of Anesthesiology and Perioperative Medicine, Division of Pain Medicine, Mayo Clinic, Rochester, MN, USA.
• ⁶ Valley Anesthesiology and Pain Consultants, Phoenix, AZ, USA; Department of Anesthesiology, University of Arizona College of Medicine-Phoenix, Phoenix, AZ; Department of Anesthesiology, Creighton University School of Medicine, Omaha, NE, USA.