Image scoring system for umbilical and uterine artery pulsed wave Doppler ultrasound measurement.
Molloholli M., Napolitano R., Ohuma EO., Ash S., Wanyonyi SZ., Cavallaro A., Giudicepietro A., Barros F., Carvalho M., Norris S., Min MAM., Zainab G., Papageorghiou AT.
OBJECTIVE: To develop an objective, image scoring system for pulsed wave Doppler measurement of maternal uterine and fetal umbilical arteries, and evaluate how the system compares with subjective assessment of the images. METHODS: As part of the quality control strategy for the INTERGROWTH-21st Project, we developed a scoring system based on six predefined criteria for uterine and umbilical artery pulsed wave Doppler measurement. The scoring system was compared to subjective assessment, which consisted simply of classifying an image as acceptable or unacceptable. Based on a sample size estimate, a total of 120 ultrasound images of umbilical and uterine artery Doppler were randomly selected from the INTERGROWTH-21st database. Two independent reviewers evaluated these images in a blinded fashion both subjectively and using the six-point scoring system. The percentage agreement and kappa statistic between the two methods were compared. RESULTS: The overall agreement between reviewers was higher for objective assessment using the scoring system (agreement: 85%, adjusted kappa: 0.70), than for subjective assessment (agreement: 70%, adjusted kappa: 0.47). The levels of agreement for the six components of the scoring system were: anatomical site (adjusted kappa: 0.97), sweep speed (0.88), magnification (0.77), velocity scale (0.68), image clarity (0.68), and angle of insonation (0.65). CONCLUSION: In quality assessment of umbilical and uterine artery pulsed wave Doppler measurements, an objective six-point image scoring system is associated with greater reproducibility than subjective assessment. We recommend this as the preferred method for quality control, audit and teaching. This article is protected by copyright. All rights reserved.