Ultrasonic fetal weight estimation: analysis of inter- and intra-observer variability.
Standard ultrasound measurements were performed by two observers in 40 third-trimester fetuses. Observers were blinded to the results of the measurements. Estimated fetal weight (EFW) was calculated using two published formulae. The intra-observer standard deviation for EFW, assessed using one-way analysis of variance, was < 75 g for both observers. The 95% prediction intervals for inter-observer comparisons of EFW, calculated using the limits of agreement method, were -187.3 g to 139.8 g, and -159.9 g to 124.3 g, using the two formulae. The results suggest that measurements of EFW are reproducible. The prediction interval is comparable to the weekly fetal weight increment in normal fetuses.
Chang
T C
TC
Department of Obstetrics and Gynaecology, University College and Middlesex School of Medicine, London, United Kingdom.
Robson
S C
SC
Spencer
J A
JA
Gallivan
S
S
D000704:Analysis of Variance; D001835:Body Weight; D005314:Embryonic and Fetal Development; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging* / Q000453:epidemiology; D005333:Fetus / Q000033:anatomy & histology*; D006801:Humans; D015588:Observer Variation; D011247:Pregnancy; D015203:Reproducibility of Results; D016216:Ultrasonography, Prenatal / Q000706:statistics & numerical data*