Feasibility and reproducibility of an image-scoring method for quality control of fetal biometry in the second trimester.
OBJECTIVE
The need for training programs and certification processes in fetal ultrasound has become obvious. The purpose of this study was to evaluate the feasibility of a score-based quality control system for fetal biometry in the second trimester.


METHODS
Standard measurements of biparietal diameter and head circumference, abdominal circumference, and femur length at 20-24 weeks had been made by four operators using the same ultrasound machine. Twenty-five of each of the cephalic, abdominal and femoral images with the calipers in place were selected arbitrarily from each operator's ultrasound database and anonymized. These 300 images were analyzed by three experienced reviewers blinded to the operator's identity. Each image was first evaluated subjectively and then scored according to six criteria for abdominal and cephalic measurements and four criteria for femur length making a six-point score for abdominal and cephalic biometry and a four-point score for femur length. For subjective evaluation, inter-reviewer differences were analyzed using percentage agreement and adjusted kappa. For objective evaluation, a difference in scoring of one point or less among reviewers was considered good agreement. Intrareviewer variability was assessed using 40 images of each type of examination selected arbitrarily.


RESULTS
The distribution of scores was similar between reviewers. One operator obtained significantly lower scores whereas the other three had good and comparable results. There was no statistical difference in the mean score attributed by each reviewer and agreement was good in 84-90% of the cases. Intrareviewer agreement was good in 90-100% of the cases, with similar scores for each reviewer.


CONCLUSIONS
A quality control policy based on image scoring is feasible and allows for fair to good inter- and intrareviewer reproducibility. The potential contribution of this approach to assess the quality of routine ultrasound examinations should be tested on a larger scale.
Salomon
L J
LJ
Service de Gynécologie-Obstétrique, Centre Hospitalier Intercommunal de Poissy-St Germain, Poissy, France.
Bernard
J P
JP
Service de Gynécologie-Obstétrique, Centre Hospitalier Intercommunal de Poissy-St Germain, Poissy, France.
Duyme
M
M
Laboratoire Biostatistique, Recherche Clinique et Santé Publique, Faculté de Médecine de Montpellier, Université Montpellier I, France.
Doris
B
B
Laboratoire Biostatistique, Recherche Clinique et Santé Publique, Faculté de Médecine de Montpellier, Université Montpellier I, France.
Mas
N
N
Laboratoire Biostatistique, Recherche Clinique et Santé Publique, Faculté de Médecine de Montpellier, Université Montpellier I, France.
Ville
Y
Y
Service de Gynécologie-Obstétrique, Centre Hospitalier Intercommunal de Poissy-St Germain, Poissy, France.
D000005:Abdomen / Q000000981:diagnostic imaging / Q000196:embryology; D001699:Biometry; D002508:Cephalometry / Q000379:methods / Q000592:standards*; D005240:Feasibility Studies; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000196:embryology; D047109:Fetal Development; D006257:Head / Q000000981:diagnostic imaging / Q000196:embryology; D006801:Humans; D015588:Observer Variation; D010294:Parietal Bone / Q000000981:diagnostic imaging / Q000196:embryology; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011786:Quality Control; D016216:Ultrasonography, Prenatal / Q000592:standards*