r

Regression line

Mean error (mm)

Error range (95% CI) (mm)

Mean error (%)

Error range (95% CI) (%)

BPD^a

0.994

y = 0.9x + 0.6

0.3

−4.1 to 4.8

0.6

−5.2 to 6.4

BPD^b

0.995

y = x − 0.1

0.7

−3.5 to 4.8

1.1

−4.5 to 6.6

FL

0.967

y = 0.9x + 4.7

-1.7

−11.4 to 8.1

−2.2

−19.4 to 15.1