Test-retest Reliability of a Peripheral Quantitative Computed Tomography Scanner for Measuring Muscle Size and Composition in Young and Older Men and Women

Abstract

Peripheral quantitative computed tomography (pQCT) has promise to simultaneously examine muscle size and composition. The purpose of this study was to examine the between- and within-day test-retest reliability of pQCT-derived mid-thigh muscle cross-sectional area (CSA), lean muscle CSA, and muscle density (MD) of the dominant thigh among young and older men and women. All variables were determined using an automatic threshold-based edge detection software and an automated enclosing convex polygon approach. Thirty-nine participants enrolled in the study and visited the laboratory completing three scans on two separate occasions. The absolute (SEM (%): 0.92 – 4.91) and relative (ICC2,1: 0.643 – 0.999) consistency values were acceptable for both protocols for muscle CSA, lean muscle CSA, and MD. Further, relative and absolute consistency values were better for the enclosing convex polygon approach.Master of Art