Assessment of Body Composition Via Dual-energy X-ray Absorptiometry Bone Densitometry

Study Overview
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Brief Summary
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The main objective of this study is to validate the measurement characteristics of a new bone densitometer, the Stratos DR: Via cross calibration to the results of body composition (BC) measurement results to those of a reference device (the Discover A by Hologic) in terms of body fat percentage, lean mass percentage of total body mass and for different subregions (left and right arms, left and right sides, lumbar and thoracic spine, pelvis, left and right legs, head, android area, gynecoid area, visceral region). And by the evaluation of the reproducibility of the BC measurement results in terms of fat mass and lean mass.

Detailed Description
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The secondary objective of this study is to cross calibrate the measures of bone mineral content (BMC) and bone mineral density (BMD) from the Stratos DR against those of the Discovery A on the whole body and its subregions.

Official Title
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Assessment of Body Composition Via Dual-energy X-ray Absorptiometry Bone Densitometry: Cross Calibration and Reproducibility Between the Stratos DR and Discovery A Bone Densitometers

Conditions
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Osteodensitometry

Intervention / Treatment
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* Device: Whole body exam using the Discovery A
* Device: First whole body exam using the Stratos DR
* Device: Second whole body exam using the Stratos DR


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The patient must have given his/her informed and signed consent The patient must be insured or beneficiary of a health insurance plan The patient is referred by a doctor for the performance of an osteodensitometry examination. Exclusion Criteria: The patient is participating in another study The patient is in an exclusion period determined by a previous study The patient is under judicial protection or any kind of guardianship The patient refuses to sign the consent It is impossible to correctly inform the patient The subject is suffering from a visually significant scoliosis The patient is pregnant or breastfeeding Patient weighing over 160 kg Patient having undergone X-ray examination using a contrast medium such as barium in the 7 days preceding the visit Patient who underwent an examination using γ rays in the 15 days preceding the visit

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: The study population: first 30 patients<br>The study population consists of adult patients referred to the Nuclear Medicine and Medical Biophysics Department of the Nîmes University Hospital for the performance of an osteodensitometric examination. Intervention: Whole body exam using the Discovery A Intervention: First whole body exam using the Stratos DR Intervention: Second whole body exam using the Stratos DR | Device: Whole body exam using the Discovery A<br>* Whole body exam using the Discovery A machine made by Hologic.<br>Device: First whole body exam using the Stratos DR<br>* First whole body exam using the Stratos DR machine made by the DMS group.<br>Device: Second whole body exam using the Stratos DR<br>* Second whole body exam using the Stratos DR machine made by the DMS group. This second exam is required for reproducibility purposes.<br>|
| Experimental: The study population: last 20 patients<br>The study population consists of adult patients referred to the Nuclear Medicine and Medical Biophysics Department of the Nîmes University Hospital for the performance of an osteodensitometric examination. Intervention: Whole body exam using the Discovery A Intervention: First whole body exam using the Stratos DR | Device: Whole body exam using the Discovery A<br>* Whole body exam using the Discovery A machine made by Hologic.<br>Device: First whole body exam using the Stratos DR<br>* First whole body exam using the Stratos DR machine made by the DMS group.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lin concordance coefficient for fat mass | The cross calibration between the two devices (Stratos vs Discovery) in terms of fat mass and lean mass is estimated by the appreciation of the Lin concordance coefficient. | Day 0 | 
| Lin concordance coefficient for lean mass | The cross calibration between the two devices (Stratos vs Discovery) in terms of fat mass and lean mass is estimated by the appreciation of the Lin concordance coefficient. | Day 0 | 
| RMS-%CV (root-mean-square coefficient of variation) for total fat mass | Reproducibility will be evaluated in terms of RMS-% CV for calculating the value of the least significant change (LSC). The values of RMS-%CV (root-mean-square coefficient of variation) of the total fat mass and total lean mass will be compared with the limit values recommended by the ISCD. (International Society for Clinical Densitometry) | Day 0 | 
| RMS-%CV (root-mean-square coefficient of variation) for total lean mass | Reproducibility will be evaluated in terms of RMS-% CV for calculating the value of the least significant change (LSC). The values of RMS-%CV (root-mean-square coefficient of variation) of the total fat mass and total lean mass will be compared with the limit values recommended by the ISCD. (International Society for Clinical Densitometry) | Day 0 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lin's concordance coefficient for Bone Mineral Content | The cross calibration between the two devices (Stratos vs Discovery) in terms of Bone Mineral Content and Bone Mineral Density will be estimated by the study of Lin's concordance coefficient. | Day 0 | 
| Lin's concordance coefficient for Bone Mineral Density | The cross calibration between the two devices (Stratos vs Discovery) in terms of Bone Mineral Content and Bone Mineral Density will be estimated by the study of Lin's concordance coefficient. | Day 0 |