Ahern DP, McDonnell J, Riffault M, et al. - Researchers conducted a meta-analysis of the diagnostic accuracy of hounsfield units on computed topography relative to dual-energy x-ray absorptiometry for the diagnosis of osteoporosis in the spine surgery population. Studies that included a comparison of the Hounsfield Unit (index test) with dual-energy x-ray absorptiometry (DXA) evaluation(reference test) were selected. Researchers evaluated data quality using the standardized QUADAS-2 criteria. They defined studies into 3 categories, based on the threshold of the index test applied with the goal of obtaining a high sensitivity, high specificity, or balanced sensitivity-specificity test. For the meta-analysis, nine studies were eligible. The Hounsfield unit (HU) was found to be a clinically useful tool to aid in the diagnosis of osteoporosis. Nevertheless, the heterogeneity seen in this study needs caution in the interpretation of outcomes. The study demonstrated the effect of differing HU threshold values on the diagnostic ability of this test. Future study is needed to evaluate the optimal HU cut-off to differentiate normal from low bone mineral density.