Interobserver variability. A source of error in obstetric ultrasound.
Several sources of error encountered in obstetrical ultrasound examination have been analyzed from a computerized ultrasound database. The variability in measuring fetal landmarks and visualization of fetal structures were found to be significantly different among three registered sonographers who examined 1,410 consecutive second and third trimester patients. The rate of successful measurement of biparietal diameter (BPD) and average abdominal diameter (AAD), as well as successful visualization of fetal stomach and/or kidneys were statistically different among the three sonographers. Only the fetal femur length was consistently measured by all three sonographers. The bias in terms of actual millimeters measured was significantly different for both BPD and AAD. The bias related to the BPD was in the magnitude of 1 mm, while the bias related to the AAD was almost 3 mm. The clinical significance of these findings and the value of the computer to perform periodic checks to assure quality control in a busy ultrasound service are discussed.
Zador
I E
IE
Department of Obstetrics and Gynecology, Wayne State University, Hutzel Hospital, Detroit, Michigan 48201.
Sokol
R J
RJ
Chik
L
L
D003951:Diagnostic Errors; D005260:Female; D005333:Fetus / Q000033:anatomy & histology*; D006801:Humans; D007256:Information Systems; D010500:Perinatology; D011247:Pregnancy; D014463:Ultrasonography