Table 1.

Sample characteristics of the training (cortex), testing (cortex), independent test (cortex) and whole blood datasets used in the development and evaluation of DNAmClock_Cortical

Dataset		Age, years					Sex, n		Illumina methylation array	References
	n	Mean	1st Quartile	Median	3rd Quartile	Range	Female	Male
Training	1047	56.53	38.56	57	78	1–108	362	685	450K	De Jager et al., 2014; Lunnon et al., 2014; Pidsley et al., 2014; Jaffe et al., 2016; Smith et al., 2018, 2019; Wong et al., 2019
Testing	350	55.87	39.05	56	78	1–108	144	206	450K	De Jager et al., 2014; Lunnon et al., 2014; Pidsley et al., 2014; Jaffe et al., 2016; Smith et al., 2018, 2019; Wong et al., 2019
Independent test	1221	83.49	78	84	90	41–104	577	644	EPIC	–
Blood	1175	57.96	46	59	69	28–98	686	489	EPIC	Hannon et al., 2018