P01.08: Fetal umbilical and middle cerebral arteries during the 2nd and 3rd trimester in low risk pregnancies: intra‐ and inter‐observer reliability and agreement

Abstract

To estimate the fetal umbilical (UA) and middle cerebral arteries (MCA) intra- and inter-observer reliability and agreement in low risk pregnancies. Singleton pregnancies between 24 and 40 weeks without major malformations were considered eligible. Each fetus was examined by 2 observers in a blinded manner: one observer performed the first scan, followed by a second observer (for inter-observer analysis), and then the first observer repeated the scan (for intra-observer analysis). In each scan, the observers assessed the pulsatility index (PI) and the resistance index (RI) from UA and MCA; peak systolic velocity (PVS) from MCA was also recorded. Reliability was assessed by intraclass correlation coefficients (ICC); agreement was assessed Bland-Altman limits of agreement (LoA) width. The following cut-off points for reliability were used: research purpose = ICC > 0.70; clinical practice = ICC > 0.90. 102 pregnant women were eligible and completed the 3 scans: gestational age was 30.2 ± 3.3 weeks, ranging from 25.0 to 38.5 weeks. Mean, SD, range, intra- and inter-observer reliability and agreement analysis are presented in the table. P01.08: Table 1. Reliability and agreement from UA and MCA PI and RI from UA, and of PI from MCA in low risk pregnancies are not reliable enough even for research purposes. RI from MCA is sufficient reliable for research; but only PVS from MCA might be considered for clinical practice.