Table 1 Slope measurements and Intraclass correlation coefficients

1

7.5°

7.6°

7.7°

8.2°

6.0°

SD 4.72°, range − 2.0° – 17.3°

SD 3.91°, range − 1.7° – 14.6°

SD 4.46°, range − 2.3° – 15.1°

SD 2.98°, range 2.2° – 14.6°

SD 2.90°, range − 0.7° – 11.9°

2

7.3°

7.6°

7.4°

8.0°

5.9°

SD 3.45°, range − 0.9° – 15.0°

SD 3.80°, range − 1.1° – 14.8°

SD 3.45°, range − 0.1° – 13.2°

SD 3.09°, range 1.1° – 14.7°

SD 3.00°, range − 4.1° – 11.8°

ICC

0.909

0.987

0.918

0.893

0.733

95% CI, 0.849; 0.946

95% CI, 0.977; 0.992

95% CI, 0.860; 0.952

95% CI, 0.823; 0.936

95% CI, 0.581; 0.836