Intra and inter-operator reliability of an ultrasonographic automated software for the assessment of endometrial receptivity assessment

Abstract Background Endometrial receptivity assessment (ERA) is considered one of the main indicators of success in assisted conception. This was a multi-centre, prospective observational study conducted in 3 university affiliated tertiary referral units. The study population comprised non-pregnant participants between 18 and 45 years of age attending the gynaecology outpatient department for a gynaecological ultrasound scan. The objectives of this study were to assess the intra-operator and inter-operator reliability of a three dimensional-ultrasound automated software (Smart ERA™) in assessing endometrial thickness (ET), endometrial volume (EV), Vascularization Index (VI), Flow Index (FI), and Vascularization Flow Index (VFI). Results A total of 226 patients were recruited into the study between December 2022 and March 2023. The mean age and BMI were 34.11 (8.71) years and 29.10 (5.15) respectively. When assessing the intra-operator relationship between the two observations using Pearson’s coefficient, ET (.93; p < .0001) and EV (.90; p < .0001) had very high correlation. The correlations for FI (.71; p < .0001), VFI (.57; p < .0001), and VI (.40; p < .0001) were high, moderate and low respectively. For the inter-operator correlation, it was high for ET (.84; p < .0001), moderate for EV (.65; p < .0001) and low for VI (.41; p < .0001), FI (.31; p < .0001), and VFI (.49; p < .0001). The inter-operator reliability was excellent for ET (0.91), substantial for EV (0.78) and VFI (0.82), moderate for VI (0.72), and low for FI (0.38). Conclusions The intra-operator and inter-operator agreement and reliability of ET and EV assessments using Smart ERA™ ranged from substantial to excellent. Similarly, the inter-operator reliability for VFI was substantial. However, the volume and flow indices had moderate to low inter-operator reliability.