Skip to main content

Table 5 Intraobserver and interobserver variability for the PT and NBL measurements

From: Utility of fetal facial markers on a second trimester genetic sonogram in screening for Down syndrome in a high-risk Thai population

Intraobserver variability (n = 100)
Parameter Operator 1 Operator 2
  Mean difference (SD) 95% LoA ICC Mean difference (SD) 95% LoA ICC
PT -0.04 (0.11) -0.06 to -0.01 0.98 -0.02 (0.12) -0.04 to 0.003 0.99
NBL 0.05 (0.16) 0.02 to 0.08 0.98 -0.03 (0.15) -0.06 to -0.001 0.98
Interobserver variability (n = 100)
  Mean difference (SD) 95% LoA ICC
PT 0.01 (0.08) -0.003 to 0.03 0.99
NBL -0.01 (0.11) -.022 to 0.02 0.99
  1. SD Standard deviation, LoA Limits of agreement, ICC intraclass correlation, PT Prenasal thickness, NBL Nasal bone length