Table 4: Differences of SD-OCT measurements between MCIs/ CINDs and controls.

We used means and standard deviations to assess the standard mean difference (SMD) and the weighted mean difference (WMD), with respective 95% confidence intervals (CIs). Heterogeneity of the included studies was assessed using standardized mean differences. Random-effects models were used in all analyses. p-values marked in bold indicate significance on the 95% confidence limit.

Variable	Overall Effect				Heterogeneity		Egger’s
	SMD (95% CI)	p value	WMD (95% CI)	p value	I2 %	Q (P)
Macular GC-IPL
Mean	−0.57 [−1.38, 0.24]	0.17	−10.19 [−20.42, 0.05]	0.05	91%	<0.00001	0.549
Macular Volume	−0.21 [−0.67, 0.25]	0.37	−0.10 [−0.31, 0.11]	0.36	61%	0.05	0.571
Peripapillary RNFL
Mean	−0.25 [−0.68, 0.18]	0.25	−2.39 [−6.34, 1.57]	0.24	80%	<0.0001	0.867
Superior	−0.10 [−0.34, 0.15]	0.44	−1.98 [−6.43, 2.47]	0.38	15%	0.32	-
Nasal	0.32 [−0.24, 0.88]	0.26	2.64 [1.80, 3.49]	<0.00001	85%	<0.0001	-
Inferior	0.12 [−0.17, 0.41]	0.42	2.13 [−3.04, 7.30]	0.42	37%	0.18	-
Temporal	0.24 [−0.66, 1.14]	0.60	−0.51 [−5.52, 4.50]	0.84	94%	<0.00001	-

Abbreviations:

MCI = Mild Cognitive Impairment; CIND = Cognitive impairment with no dementia; C = Control; SMD = Standardized mean difference; WMD = Weighted mean difference; GC-IPL = Ganglion cell-inner plexiform layer thickness; RNFL = Retinal nerve fibre layer thickness