Standardization and quality control of Doppler and fetal biometry ultrasound measurements in low-income setting

Objective: We aimed to determine the quality of fetal biometry and pulse-wave Doppler ultrasound measurements in a prospective cohort study in Uganda. Methods: This was an ancillary study in the Ending Preventable Stillbirths by Improving Diagnosis of Babies at Risk (EPID) project where women enrolled in early pregnancy were subjected to Doppler and fetal biometry ultrasound assessments between 32 and 40 weeks of gestation. A total of 125 images for each of the umbilical (UA), middle cerebral (MCA), uterine (UtA) arteries, head circumference (HC), abdominal circumference (AC) and femur length (FL) were arbitrarily selected from the EPID study database and independently evaluated by two experts in a blinded fashion using an objective scoring criterion. Inter-rater agreement was assessed using modified Fleiss’ Kappa for nominal variables and systematic errors were explored using Q-Q plots. Results: Over 96.8% of the UA images, 84.8% of the MCA images and 93.6% of the UtA images were classified as of acceptable quality by both reviewers. For fetal biometry measurements, 96.0% of the HC images, 96.0% of the AC images and 88.0% of the FL images were acceptable. The Kappa values for inter-rater reliability of quality assessment were 0.94 (95% CI, 0.87–0.99), 0.71 (95% CI, 0.58–0.82), and 0.87 (95% CI, 0.78–0.95), for the UA, MCA, and UtA, respectively. The inter-rater agreement HC was 0.94 (95% CI, 0.87–0.98) for the HC, 0.93 (95% CI, 0.87–0.98) for the AC and 0.78 (95% CI, 0.66–0.88) for the FL measurements.The Q-Q plots indicated no influence of systematic biases in the measurements. Conclusion: Training local healthcare providers to perform Doppler ultrasound, and implementation of quality control systems and audits of measurements using objective scoring tools in clinical and research settings of low- and middle-income countries is feasible. Although we did not assess the impact of in-service re-training offered to practitioners deviating from prescribed standards in this study, such interventions could possibly enhance the quality of the ultrasound measurements and should be investigated in future studies. This article is protected by copyright. All rights reserved.