Correcting magnification error in foveal avascular zone area measurements of optical coherence tomography angiography images with estimated axial length

Table 2 Bland-Altman analysis and paired t-test showing agreement between estimated and actual axial length

Parameters	Mean diff. (mm) (95% CI)	SD (mm)	Lower LoA (95% CI)	Upper LoA (95% CI)	t_stat (df)	P value	R²	ICC (95% CI)
Validation dataset (post-cycloplegic SE)	0.012 (− 0.025, 0.049)	0.486	− 0.940 (− 1.005, − 0.877)	0.965 (0.901, 1.029)	0.632 (649)	0.527	0.710	0.831 (0.806, 0.921)
Validation dataset (non-cycloplegic SE)	0.095 (0.055, 0.135)	0.519	− 0.922 (− 0.990, − 0.854)	1.113 (1.044, 1.181)	4.683 (650)	< 0.005	0.670	0.802 (0.769, 0.830)
OCTA test dataset (non-cycloplegic SE)	0.029 (− 0.154, 0.212)	0.616	− 1.179 (− 1.494, − 0.864)	1.236 (0.921, 1.551)	0.439 (45)	0.755	0.800	0.892 (0.812, 0.939)

CI = confidence interval; df = degrees of freedom; ICC = intraclass coefficient; LoA = limits of agreement; OCTA = optical coherence tomography angiography; SE = spherical equivalent; SD = standard deviation; t_stat = t-statistic

ISSN: 2326-0254