Supplementary material
Table A
Reference Study, IQ test, subtests, intraclass correlations for monozygotic (MZ) and dizygotic (DZ) twins and their 95% CI, g loadings, heritability estimates reported by author(s), estimated by the adjusted Falconer method, and structural equation model-fitting analysis (SEM), and correlations between g loadings and heritabilities
study |
IQ test |
subtest |
Twin correlation |
g |
h2 |
||||
|
|
|
MZ |
DZ |
|
Authorreport |
Falconeradj |
SEM |
|
Takuma (1968) |
|
maze |
.80 (.69,.87) |
.20 (-.34,.64) |
.660 |
.753 |
.80 |
.80 |
|
|
cubic analysis |
.53 (.32,.68) |
.11 (-.42,.58) |
.546 |
.466 |
.53 |
.52 |
||
|
geometry |
.46 (.24,.63) |
-.02 (-.52,.49) |
.631 |
.472 |
.46 |
.45 |
||
Tanaka-B |
replacement |
.62 (.45,.76) |
.24 (-.30,.67) |
.757 |
.503 |
.624 |
.62 |
||
|
matching |
.58 (.39,.72) |
.20 (-.34,.64) |
.628 |
.477 |
.580 |
.58 |
||
|
sequence |
.58 (.38,.72) |
-.19 (-.63,.35) |
.649 |
.643 |
.575 |
.56 |
||
|
elimination |
.73 (.58,.82) |
-.12 (-.59,.41) |
.655 |
.754 |
.725 |
.72 |
||
r(g x h2)1 |
|
|
|
|
|
|
.369 |
.373 |
|
r(g x h2)2 |
|
|
|
|
|
|
.369 |
.373 |
|
|
|
memory(verbal) |
.68 (.56,.77) |
.18 (-.22,.53) |
.648 |
.612 |
.682 |
.68 |
|
|
memory (figure) |
.35 (.16,.51) |
.13 (-.27,.49) |
.475 |
.251 |
.345 |
.34 |
||
|
spatial 1 |
.38 (.21,.54) |
.28 (-.12,.59) |
.489 |
.141 |
.202 |
.20 |
||
Ushijima |
spatial 2 |
.46 (.30,.61) |
-.18 (-.53,.22) |
.395 |
.546 |
.463 |
.43 |
||
|
quantity |
.59 (.45,.70) |
.03 (-.36,.41) |
.754 |
.582 |
.592 |
.58 |
||
|
antonym |
.55 (.39,.67) |
.00 (-.39,.38) |
.775 |
.547 |
.545 |
.53 |
||
|
verb. reasoning |
.68 (.56,.77) |
.11 (-.29,.47) |
.633 |
.639 |
.680 |
.68 |
||
|
spatial reasoning |
.65 (.52,.75) |
-.22 (-.55,.18) |
.588 |
.712 |
.648 |
.65 |
||
r(g x h2)1 |
|
|
|
|
|
|
.587 |
.596 |
|
r(g x h2)2 |
|
|
|
|
|
|
.587 |
.596 |
|
|
|
cube |
.62 (.50,.71) |
.31 (-.04,.59) |
.562 |
.45 |
.618 |
.61 |
|
|
verbal reasoning |
.59 (.47,.69) |
.43 (.09,.67) |
.692 |
.284 |
.326 |
.33 |
||
Nokenshiki |
odd man |
.51 (.38,.63) |
.50 (.18,.72) |
.552 |
.036 |
.036 |
.04 |
||
|
time lapse |
.33 (.17,.47) |
.60 (.32,.78) |
.507 |
-.679 |
0 |
0 |
||
|
analogy |
.47 (.33,.59) |
.47 (.14,.70) |
.650 |
.006 |
.006 |
.01 |
||
r(g x h2)1 |
|
|
|
|
|
|
.150 |
.161 |
|
r(g x h2)2 |
|
|
|
|
|
|
n.a. |
n.a. |
|
|
|
intuition (figure) |
.27 (.00,.50) |
.23 (-.28,.63) |
.41 |
.054 |
.084 |
.08 |
|
|
intuition (verbal) |
.51 (.27,.68) |
.21 (-.30,.62) |
.49 |
.378 |
.506 |
.50 |
||
Todai AS |
logic (figure) |
.35 (.09,.57) |
.34 (-.17,.70) |
.40 |
.017 |
.022 |
.02 |
||
|
logic (verbal) |
.36 (.10,.57) |
.16 (-.34,.59) |
.51 |
.236 |
.356 |
.35 |
||
|
memory |
.34 (.08,.56) |
.02 (-.45,.49) |
.36 |
.327 |
.342 |
.32 |
||
r(g x h2)1 |
|
|
|
|
|
|
.531 |
.559 |
|
r(g x h2)2 |
|
|
|
|
|
|
n.a. |
n.a. |
|
|
|
figure recognition |
.59 (.48,.69) |
.55 (.27,.75) |
.37 |
.090 |
.08 |
.08 |
|
|
sequence completion |
.68 (.58,.76) |
.12 (-.23,.45) |
.57 |
.636 |
.681 |
.68 |
||
|
verbal analogy |
.58 (.46,.69) |
.38 (.05,.64) |
.57 |
.325 |
.402 |
.40 |
||
Koga |
figure rotation |
.75 (.67,.82) |
.53 (.24,.74) |
.57 |
.469 |
.438 |
.44 |
||
|
replacement and addition |
.72 (.63,.79) |
.34 (.00,.61) |
.37 |
.577 |
.721 |
.72 |
||
|
sentence completion |
.49 (.36,.61) |
.28 (-.07,.57) |
.49 |
.295 |
.424 |
.42 |
||
|
finding shapes |
.45 (.31,.57) |
.38 (.05,.64) |
.40 |
.115 |
.142 |
.14 |
||
r(g x h2)1 |
|
|
|
|
|
|
.359 |
.360 |
|
r(g x h2)2 |
|
|
|
|
|
|
.087 |
.089 |
|
|
|
antonym |
.58 (.38,.72) |
.38 (-.12,.72) |
.815 |
.322 |
.402 |
.40 |
|
|
memory |
.56 (.36,.71) |
0 (-.47,.47) |
.695 |
.56 |
.560 |
.55 |
||
|
finding the same figure |
.48 (.26,.65) |
.23 (-.28,.63) |
.620 |
.327 |
.48 |
.48 |
||
|
odd-man out |
.34 (.10,.55) |
.27 (-.23,.66) |
.700 |
.101 |
.128 |
.13 |
||
Kyodai NX |
points to form a figure |
.36 (.11,.56) |
.10 (-.40,.54) |
.610 |
.287 |
.335 |
.33 |
||
|
replacement |
.44 (.21,.62) |
.28 (-.22,.67) |
.645 |
.219 |
.314 |
.31 |
||
|
word completion |
.74 (.61,.84) |
.28 (-.22,.67) |
.700 |
.644 |
.743 |
.74 |
||
|
arithmetic |
.56 (.36,.71) |
.19 (-.31,.61) |
.620 |
.457 |
.561 |
.56 |
||
|
matrix |
.41 (.18,.60) |
0 (-.47,.47) |
.615 |
.41 |
.410 |
.39 |
||
r(g x h2)1 |
|
|
|
|
|
|
-.010 |
.012 |
|
r(g x h2)2 |
|
|
|
|
|
|
-.010 |
.012 |
|
Ando et al. (2001) |
|
spatial storage |
.50 (.36,.62) |
.04 (-.17,.25) |
.596 |
.92 |
.50 |
.47 |
|
|
spatial executive |
.50 (.36,.62) |
.22 (.01,.41) |
.545 |
.56 |
.50 |
.50 |
||
Kyodai-NX |
verbal storage |
.45 (.31,.57) |
.34 (.14,.51) |
.579 |
.22 |
.22 |
.22 |
||
+ 4 subtests |
verbal executive |
.44 (.30,.56) |
.23 (.01,.41) |
.547 |
.42 |
.42 |
.42 |
||
|
spatial ability |
.68 (.55,.78) |
.34 (.14,.51) |
.708 |
.68 |
.68 |
.68 |
||
|
verbal ability |
.66 (.52,.77) |
.22 (-.03,.45) |
.564 |
.88 |
.66 |
.65 |
||
r(g x h2)1 |
|
|
|
|
|
|
.458 |
.46 |
|
r(g x h2)2 |
|
|
|
|
|
|
.458 |
.46 |
|
Toyoda et al. (2004) |
|
maze |
|
|
.660 |
|
n.a. |
n.a. |
|
|
cubic analysis |
|
|
.546 |
.39 |
.39 |
.39 |
||
|
geometry |
|
|
.631 |
0 |
0 |
0 |
||
Tanaka-B |
replacement |
|
|
.757 |
0 |
0 |
0 |
||
|
matching |
|
|
.628 |
.02 |
.02 |
.02 |
||
|
sequence |
|
|
.649 |
.19 |
.19 |
.19 |
||
|
elimination |
|
|
.655 |
|
n.a. |
n.a. |
||
r(g x h2)1 |
|
|
|
|
|
|
-.708 |
-.708 |
|
r(g x h2)2 |
|
|
|
|
|
|
n.a. |
n.a. |
|
Shikishima et al. (2009) |
|
logic(content-based) |
.47 (.34,.58) |
.28 (-.04,.55) |
.728 |
.38 |
.38 |
.38 |
|
|
logic(abstract) |
.41 (.28,.53) |
.39 (.09,.63) |
.748 |
.04 |
.04 |
.04 |
||
|
logic(graphical) |
.59 (.48,.68) |
.20 (-.12,.48) |
.810 |
.78 |
.59 |
.59 |
||
|
logic(congruent) |
.54 (.42,.64) |
.15 (-.17,.44) |
.887 |
.78 |
.54 |
.53 |
||
|
logic(incongruent) |
.56 (.45,.66) |
.16 (-.16,.45) |
.879 |
.80 |
.56 |
.55 |
||
Kyodai-NX |
word completion |
.48 (.36,.59) |
.20 (-.12,.48) |
.260 |
.56 |
.48 |
.48 |
||
+ 5 subtests |
sentence completion |
.63 (.53,.71) |
.58 (.32,.76) |
.561 |
.10 |
.10 |
.10 |
||
|
antonym, synonym |
.55 (.44,.65) |
.60 (.35,.77) |
.535 |
-.10 |
0 |
0 |
||
|
word rearrangement |
.46 (.33,.57) |
.18 (-.14,.47) |
.505 |
.56 |
.46 |
.46 |
||
|
punching a folded paper |
.47 (.34,.58) |
.31 (.00,.57) |
.377 |
.32 |
.32 |
.32 |
||
|
figure combination |
.52 (.40,.62) |
.18 (-.14,.47) |
.401 |
.68 |
.52 |
.52 |
||
|
figures and letter plate |
.53 (.41,.63) |
.29 (-.03,.55) |
.458 |
.48 |
.48 |
.48 |
||
|
sociogram |
.39 (.25,.51) |
.21 (-.11,.49) |
.391 |
.36 |
.36 |
.36 |
||
r(g x h2)1 |
|
|
|
|
|
|
.113 |
.102 |
|
r(g x h2)2 |
|
|
|
|
|
|
.536 |
.514 |
Note. The g loadings of subtests of Tanaka-B, Ushijima, Nokenshiki, and Kyodai NX were estimated from correlation matrices using PAF, whereas those of Koga and Todai AS were taken from Carroll (1993), based on the narrow abilities they measured. Ando et al. and Shikishima et al. report both their subtests’ g loadings and heritabilities. Toyoda et al. report highly unusual g loadings for the subtests maze and elimination, so we used the g loadings that we also used for the Tanaka-B data from Takuma (1968). n.a. = not applicable
r(g x h2)1 = correlation between all g loadings and all heritabilities; r(g x h2)2 = correlations between g loadings and all heritabilities, excluding all values of h2 ≤ .10.The values of h2 ≤ .10 are in bold.