Observational Studies in Orthopaedic Surgery: The STROBE Statement as a Tool for Transparent Reporting

What Are the Levels of Evidence on Which We Base Decisions for Surgical Management of Lower Extremity Bone Tumors?

“…Whereas the reporting of observational studies is often not clear enough to allow assessment of strengths and weaknesses, STROBE specifically considers sources of bias and clarifies the interpretation and applicability of a study's results and conclusions [34]. It has been adopted by many top journals and is readily available to authors, editors, and reviewers [5,30]. Because the STROBE checklist can only be applied to observational study designs that have comparative groups, we examined the quality of reporting of the prospective and retrospective controlled observational studies but excluded the retrospective uncontrolled studies (case series), case reports, and any RCTs from analysis with STROBE.…”

“…In total, there are 34 items that can be evaluated for each study. Under the supervision of a senior investigator (MG), two independent reviewers (NE, JN) learned to use the STROBE checklist by reviewing a published explanatory article and a published practical application guide [30,35]. The published application guide was used to define the criteria required to score each STROBE item as adequately reported [30,35].…”

“…2 The distribution of the levels of evidence for therapeutic studies in the surgical management of primary lower extremity bone tumors illustrates the high prevalence of level III-V studies. required a description of how losses were handled statistically and whether lost subjects may have systematically differed from non-lost subjects, thereby biasing the study results [30]; (8) describing whether there were any sources of funding and the role of any funders (19% reported). Standard disclosures of funding sources were considered adequate even if details about the role of the funders were not provided; (9) indicating the number of participants with missing data for each data point (26% reported); and (10) explaining how quantitative variables were handled in the analyses (29% reported).…”

“…Observational studies inform clinicians about disease etiology, natural history, prognostic factors, and treatment effectiveness, but they are prone to confounding bias, sampling bias (including selection bias), and recall bias [30]. Confounding bias is the possibility of an unknown variable being causally linked to both an exposure and an outcome, whereas sampling bias is a systematic error in participant selection that may inadequately represent a population of interest, and recall bias is the inaccuracy with which test subjects retrospectively recall prior events or health states.…”

“…Transfer bias, or unequal loss to followup between groups, also is a common limitation in observational studies. These biases limit the validity and applicability of results from observational studies [30].…”