Table 1.
Bivariate model fitting for time 1 anxiety and time 2 depression
Rater | Aanx | Canx | Eanx | Ac | Cc | Ec | Adep | Cdep | Edep | χ2 | AIC | ||||||||||
Parent rated total sample NMZ = 138 NDZ = 210 |
46*** | 24*** | 30*** | 13** | 36*** | 2 ns | 24* | 0 ns |
26*** | 15.36 df = 11 |
-6.64 | ||||||||||
Parent rated – adolescents only (8–14 at time 1 and 11–17 at time 2) NMZ = 90 NDZ = 136 |
46*** | 23** | 31*** | 11* | 34** | 4 ns | 25* | 0 ns |
25*** | 15.02 df = 11 |
-6.98 | ||||||||||
Parent rated anxiety time 1 and self rated depression time 2 NMZ = 92 NDZ = 128 |
53*** | 15 ns | 32*** | 13* | 17 ns | 2 ns | 36** | 0 ns |
31*** | 5.80 df = 11 |
-16.20 |
Ns = non significant
* p = .05
** p = .01
*** p = .001
Aanx genetic influences on anxiety
Canx common environmental influences on anxiety
Eanx non shared environmental influences on anxiety
Ac genetic influences on anxiety that also influence depression
Cc common environmental influences on anxiety that also influence depression
Ec non shared environmental influences on anxiety that also influence depression
Adep genetic influences specific to depression
Cdep common environmental influences specific to depression
Edep non shared environmental influences specific to depression
NMZ = number of MZ twin pairs
NDZ = number of DZ twin pairs
Parameter estimates equated to sum 100 in direction of arrows on each trait (anxiety time 1 & depression time 2)