Table 3. Linear ANCOVA analyses with regional 5-HT₄ receptor binding as a dependent variable, and age and sex as explanatory variables.

	Uncorrected 5-HT4 receptor binding			PV-corrected 5-HT4 receptor binding
	Estimate±s.e.	P value	R2	Estimate±s.e.	P value	R2
Neocortex
Age	−0.0020±0.0005	0.0009		0.00096±0.0007	0.20
Sex	−0.028±0.022	0.21	0.39	−0.073±0.029	0.017	0.21
Limbic system
Age	−0.0021±0.0006	0.001		−0.00016±0.0008	0.84
Sex	−0.064±0.025	0.016	0.42	−0.095±0.031	0.0048	0.27
Striatum
Age	−0.0099±0.0020	<0.0001		−0.0085±0.0031	0.010
Sex	−0.13±0.08	0.11	0.52	−0.21±0.12	0.10	0.31

ANCOVA, analysis of covariance; PV, partial volume.

PV corrected values are the primary outcomes. Analyses are performed for each region one by one, and sex differences are analyzed with men as reference.