P46. Clinical level of evidence presented at the Lumbar Spine Research Society (LSRS) Annual Meeting over 10 years (2008-2017): a systematic review

BACKGROUND CONTEXT The Lumbar Spine Research Society (LSRS) is dedicated to advancing knowledge of the lumbar spine to promote evidence-based care. PURPOSE We systematically reviewed the level of clinical evidence presented at LSRS annual meetings from 2008 through 2017. METHODS A total of 458 paper abstracts presented at LSRS annual meetings were independently assessed by two reviewers. Abstracts were excluded based on specific criteria resulting in only clinical studies being included for analyses. Reviewers designated a clinical level of evidence (LOE) to each included abstract from level I to level IV based on criteria set forth by the American Academy of Orthopaedic Surgeons (AAOS). Reviewer agreement was assessed using Cohens Kappa coefficient (k) and disagreements were subsequently discussed until a consensus was reached. Students t-test was used to assess for differences in mean LOE grades. Chi-squared testing was used to assess nonrandom changes in level of evidence. RESULTS A total of 299 abstracts met the inclusion criteria. Over the last 10 LSRS meetings, 2.68% of the presentations were level I, 22.4% were level II, 37.1% were level III, and 37.8% were level IV. We found the average LOE from 2008 to 2017 to be 3.10 (median = 3). Additionally, 63.9% presentations were Therapeutic Studies, 30.1% were Prognostic Studies and 6.02% were Diagnostic studies. When comparing the first five years (2008-2012) to the last five years (2013-2017), we observed a significant increase in Level II (p CONCLUSIONS Emphasis on evidence-based medicine within spine surgery, specifically pertaining to the lumbar spine, has positively influenced the clinical level of evidence disseminated at LSRS Annual Meetings between 2008 and 2017. Continued focus on higher quality Level I studies is warranted. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.