Assessment of Biological Age With Conventional Ultrasound Imaging as an Alternative to X‐Ray—A Pilot Study in Youth Soccer

Figures

• 

  FIGURE 1. Scatter plot of the intraclass correlation for the difference in biological age and chronological age (BA‐CA) assessed by X‐ray and conventional US, with a trend line illustrating the relationship between the methods.

• 

  FIGURE 2. Biological age assessed by X‐ray and conventional ultrasound scans, with the line of identity (dashed line), the linear regression line (solid line) and the linear regression equation.

• 

  FIGURE 3. Bland–Altman plot representing biological age (in years) derived from X‐ray and conventional ultrasound. The solid line indicates the mean difference line, and the dotted lines represent the 95% of agreement (± 1.96 times the standard deviation).

• 

  FIGURE A1. Left hand‐wrist X‐ray of participant eight.

• 

  FIGURE A2. Ultrasound scan of the radius (participant 8) with the diameter of the ossification centre (= 9.81 mm) and diameter of the epiphysis (= 18.16 mm), resulting in an ossification ratio of 0.54.

• 

  FIGURE A3. Ultrasound scan of ulna (participant 8) with the diameter of the ossification centre (= 3.32 mm) and diameter of the epiphysis (= 10.88 mm), resulting in an ossification ratio of 0.31.

• 

  FIGURE A4. Validation process of a conventional ultrasound for determining biological age based on accuracy, precision and reliability. Key analyses include correlation, linear regression analysis and agreement measures.