Reviewer Report.pdf

The reviewer suggests shortening the manuscript to focus on the correlation of vertebral fat fraction (FF) with areal bone mineral density (aBMD) and volumetric bone mineral density (vBMD), as these are the most important results. The use of two definitions of osteoporosis, one using DXA and one using QCT, is confusing and should be avoided. The diagnosis of osteoporosis is of secondary interest, and the correlation of FF with vBMD is relatively low, explaining less than 40% of the variation of vBMD. The clinical relevance of this correlation remains unclear and should be discussed in more detail. The AUC analysis is unclear and should be removed, and the manuscript should avoid using the term "bone quality" as it is not well-defined. The significance of bone marrow adipose tissue (BMAT) in the introduction should be down-tuned, and the manuscript should be balanced and objective in discussing different protocols for BMAT measurements. The reviewer also suggests clarifying the CT and MRI protocols, using consistent terminology, and reporting %RMS-CV values instead of ICC values. The discussion section should be shortened and focused on the results of the study, and the conclusion should be revised as it is not supported by the data.