Strengths and Limitations
In addition to the multicenter clinical trial design, the relatively large sample size and follow-up period, the strengths of our study include use of repeatedly measured data and determination of body composition with precise imaging techniques with standardized measurements. The trial also has limitations. First, our findings are based on interim analysis of the intermediate outcomes of an ongoing RCT. Second, the generalizability of these results to other populations (younger and/or healthier) may be limited. Furthermore, measures of body composition were not available in the total cohort, due to limited access to DXA scanners in most of the recruiting centers. Lastly, there were losses to follow-up in DXA participation leading to missing data in body composition variables; however, the results were similar when multiple imputation was conducted.