The Influence of Sonographer Experience on Skeletal Muscle Image Acquisition and Analysis

The amount of experience with ultrasonography may influence measurement outcomes while images are acquired or analyzed. The purpose of this study was to identify the interrater reliability of ultrasound image acquisition and image analysis between experienced and novice sonographers and image analysts, respectively. Following a brief hands-on training session (2 h), the experienced and novice sonographers and analysts independently performed image acquisition and analyses on the biceps brachii, vastus lateralis, and medial gastrocnemius in a sample of healthy participants (n = 17). Test-retest reliability statistics were computed for muscle thickness (transverse and sagittal planes), muscle cross-sectional area, echo intensity and subcutaneous adipose tissue thickness. The results show that image analysis experience generally has a greater impact on measurement outcomes than image acquisition experience. Interrater reliability for measurements of muscle size during image acquisition was generally good-excellent (ICC_2,1: 0.82-0.98), but poor-moderate for echo intensity (ICC_2,1: 0.43-0.77). For image analyses, interrater reliability for measurements of muscle size for the vastus lateralis and biceps brachii was poor-moderate (ICC_2,1: 0.48-0.70), but excellent for echo intensity (ICC_2,1: 0.90-0.98). Our findings have important implications for laboratories and clinics where members possess varying levels of ultrasound experience.