Table 3 Quadratic-weighted Cohen’s κ values of interobserver agreement for each pair of the five readers

Centre 1 reader 1

Centre 1 reader 1

-

Centre 1 reader 2

Centre 1 reader 2

0.764 (0.712–0.816)

-

Centre 2 reader 1

Centre 2 reader 1

0.528 (0.473–0.582)

0.618 (0.554–0.682)

-

Centre 2 reader 2

Centre 2 reader 2

0.478 (0.421–0.535)

0.615 (0.546–0.684)

0.834 (0.800–0.869)

-

Centre 2 reader 3

0.449 (0.387–0.511)

0.579 (0.503–0.656)

0.792 (0.739–0.844)

0.872 (0.834–0.910)