Discrepancies in the Definition of “Outpatient” Surgeries and Their Effect on Study Outcomes Related to ACDF and Lumbar Discectomy Procedures: A Retrospective Analysis of 45,204 Cases

Study Design:This is a retrospective study.Objective:To study the differences in definition of “inpatient” and “outpatient” [stated status vs. actual length of stay (LOS)], and the effect of defining populations based on the different definitions, for anterior cervical discectomy and fusion (ACDF) a