Sheehan KJ, et al. - In this scoping review, researchers analyzed prognostic factors influencing complications after hip fracture surgery and summarized the underlying mechanisms proposed for their influence. They summarized the extent, nature, and proposed underlying mechanisms narratively and in a dependency graph for the prognostic factors of complications. From 56 studies, they identified 44 prognostic factors of in-hospital complications following hip fracture surgery. Of these, they identified seven patient factors - dehydration, anemia, hypotension, variability in heart rate, pressure risk, nutrition, and use of catheter indwelling ; and seven process factors - time for surgery, anesthetic type, transfusion strategy, orthopedic vs geriatric/co-managed care, multidisciplinary care pathway, and potentially modifiable during index hospitalization. According to findings, most factors have been reported for their influence through one study with no proposed underlying mechanism. There was inconsistency in reported associations where reported by more than one study and the conceptualization of complications differed, limiting comparison across studies. Therefore, it is not possible to be certain whether intervening on these factors would lessen the rate of complications following hip fracture surgery.