Table S8.
Model | Base | EP | Model fit |
Df | AIC | Δ–2LL | Δ df | p | |
---|---|---|---|---|---|---|---|---|---|
–2LL | |||||||||
Paranoia | Saturated model | 10 | 15445.00 | 9993 | –4541.00 | ||||
ACE | Sat | 11 | 15445.00 | 9994 | –4543.00 | 0.01 | 1 | .999 | |
AE (retained C for tobacco)a | ACE | 9 | 15446.78 | 9996 | –4545.22 | 1.78 | 2 | .411 | |
ACE dropped rA | ACE | 10 | 15447.58 | 9995 | –4542.42 | 2.58 | 1 | .108 | |
ACE dropped rC | ACE | 10 | 15445.17 | 9995 | –4544.83 | 0.17 | 1 | .682 | |
ACE dropped rA and rC | ACE | 9 | 15466.39 | 9996 | –4525.61 | 21.39 | 2 | <.001 | |
AE dropped rA | ACE | 8 | 15468.29 | 9997 | –4525.71 | 23.29 | 3 | <.001 | |
Hallucinations | Saturated model | 10 | 15613.03 | 10001 | –4388.97 | ||||
ACE | Sat | 11 | 15613.03 | 10002 | –4390.97 | 0.01 | 1 | .999 | |
AE (retained C for tobacco) | ACE | 9 | 15621.10 | 10004 | –4386.90 | 8.07 | 2 | .018 | |
ACE dropped rA | ACE | 10 | 15614.98 | 10003 | –4391.02 | 1.95 | 1 | .162 | |
ACE dropped rCa | ACE | 10 | 15613.04 | 10003 | –4392.96 | 0.01 | 1 | .929 | |
ACE dropped rA and rC | ACE | 9 | 15625.36 | 10004 | –4382.64 | 12.34 | 2 | .002 | |
Cognitive disorganization | Saturated model | 10 | 15583.50 | 9993 | –4402.50 | ||||
ACE | Sat | 11 | 15583.62 | 9994 | –4404.38 | 1.12 | 1 | .733 | |
AE (retained C for tobacco) a | ACE | 9 | 15583.63 | 9996 | –4408.38 | 0.01 | 2 | .998 | |
ACE dropped rA | ACE | 10 | 15589.15 | 9995 | –4400.85 | 5.53 | 1 | .019 | |
ACE dropped rC | ACE | 10 | 15583.63 | 9995 | –4406.38 | 0.01 | 1 | .944 | |
ACE dropped rA and rC | ACE | 9 | 15615.04 | 9996 | –4376.96 | 31.42 | 2 | <.001 | |
AE dropped rA | ACE | 8 | 15615.04 | 9997 | –4378.96 | 31.42 | 3 | <.001 | |
Negative symptoms | Saturated model | 10 | 14113.87 | 10003 | –5892.13 | ||||
ACE a | Sat | 11 | 14113.87 | 10004 | –5894.13 | 0.01 | 1 | 0.999 | |
(parent-rated) | AE (retained C for tobacco) | ACE | 9 | 14144.63 | 10006 | –5867.37 | 30.76 | 2 | <.001 |
ACE dropped rA | ACE | 10 | 14117.12 | 10005 | –5892.88 | 3.25 | 1 | 0.072 | |
ACE dropped rC | ACE | 10 | 14117.19 | 10005 | –5892.81 | 3.32 | 1 | 0.069 | |
ACE dropped rA and rC | ACE | 9 | 14162.75 | 10006 | –5849.25 | 48.88 | 2 | <.001 |
Note: Saturated models constrained means, thresholds and phenotypic correlations across twin order. Nonsmokers defined as those who had never smoked or who smoked less than 50 lifetime cigarettes. Smokers were those who smoked 50 or more lifetime cigarettes and who smoked in the past year. –2LL = minus 2 log-likelihood; Δdf = difference in degrees of freedom compared to the base model; Δ–2LL=log-likelihood ratio chi-square test comparing the –2LL of each model to the –2LL fit of the base model; A = additive genetic influences; Base = comparison model; AIC = Akaike's Information Criterion (lower values reflect a more parsimonious and therefore preferred fit); C = common environmental influences; df = degrees of freedom; E = unique environmental influences; EP = estimated parameters; rA = genetic correlation; rC = common environmental correlation; rE = unique environmental correlation
Most parsimonious model.