Table 2.

Three longitudinal linear mixed models (see equation (1)) of data from 388 participants in the Aberdeen 1936 Birth Cohort Study. Socioeconomic status childhood (SESc) and socioeconomic status mobility (SESm). All associations are significant unless indicated (ns).

		Model 1	Model 2	Model 3
		Effect (standard error)	Effect (standard error)	Effect (standard error)
${\mathit{\beta }}_{\mathit{0}\mathit{j}}$	Intercept	63.4 (5.6)	70.7 (6.3)	89.7 (5.0)
${\mathit{\beta }}_{\mathit{1}\mathit{j}}$	Age	–0.54 (0.11)	–1.73 (0.54)	–1.74 (0.54)
${\mathit{\beta }}_{\mathit{2}}$	Practice	4.33 (0.66)	4.42 (0.66)	4.51 (0.66)
${\mathit{\beta }}_{\mathit{3}}$	Sex	8.56 (1.27)	8.57 (1.12)	8.94 (1.15)
${\mathit{\beta }}_{\mathit{4}}$	Childhood ability	0.24 (0.05)	0.24 (0.05)
${\mathit{\beta }}_{\mathit{5}}$	Education	0.84 (0.33)	0.20 (0.44) ns	0.60 (0.44) ns
${\mathit{\beta }}_{\mathit{6}}$	SESc	1.84 (0.84)	2.47 (1.16)	4.00 (1.14)
${\mathit{\beta }}_{\mathit{7}}$	SESm	1.17 (0.70) ns	1.88 (0.96)	3.00 (0.95)
${\mathit{\beta }}_{\mathit{A}}$	Age × education		0.11 (0.05)	0.11 (0.05)
${\mathit{\beta }}_{\mathit{B}}$	Age × SESc		–0.10 (0.13) ns	–0.10 (0.13) ns
${\mathit{\beta }}_{\mathit{C}}$	Age × SESm		–0.12 (0.11) ns	–0.12 (0.11) ns
${\mathit{u}}_{\mathit{0}\mathit{j}}$	Intercept variance	86.5 (16.3)	87.1 (16.3)	95.2 (16.9)
${\mathit{u}}_{\mathit{1}\mathit{j}}$	Age variance	0.62 (0.17)	0.61 (0.16)	0.61 (0.16)
${\mathit{\rho }}_{\mathit{0},\mathit{1}}$	Intercept/age covariance	–1.56 (1.44) ns	–1.56 (1.43) ns	–1.63 (1.45) ns
${\mathit{e}}_{\mathit{i},\mathit{j}}$	Residual	59.6 (3.49)	59.3 (3.5)	59.3 (3.5)
	−2Loglikihood	8841.5	8836.2	8859.5