Bedside quantification of fat-free mass in acute spinal cord injury using bioelectrical impedance analysis: A psychometric study

Abstract

Study Design: Psychometric. Objectives: Assess the validity of bioimpedance-based measures of fat-free mass (FFM) in acute SCI and of current definitions of obesity based on body mass index (BMI). Setting: Australia. Methods: All admissions within eight weeks of a new traumatic SCI were screened. 29% were eligible. 71% of those consented. Twenty participants (18 male) completed deuterium dilution (DD) and bioimpedance-based measurements of FFM. Thirteen also underwent dual-energy X-ray absorptiometry. Strength of relationships and agreement were examined using Lin's concordance coefficient and limits of agreement analysis, respectively. Sensitivity and specificity were calculated for three B..