Table 1: Studies included in the meta-analysis.

Sample and StudyInstrumentInformantAgeTwinsEffect size

Cardiff Study (CaStANET) [9]MFQMother8–17MZ_M
MZ_F
DZ_M
DZ_F
DZ_OS
262
323
178
231
420
.71
.79
.64
.69
.59
MFQ Child11–17 MZ_M
MZ_F
DZ_M
DZ_F
DZ_OS
153
209
111
156
251
.54
.61
.32
.45
.23

Registry for Child Twins [10]CDIChild12–16MZ_M
MZ_F
DZ_M
DZ_F
DZ_OS
50
64
44
44
42
.63
.61
.22
.54
.10

Finn Twin [16] MPNIMother12MZ_M
MZ_F
DZ_M
DZ_F
DZ_OS
213
245
242
223
443
.60
.60
.40
.38
.44
CDIChild12MZ_M
MZ_F
DZ_M
DZ_F
DZ_OS
89
108
84
73
145
.42
.54
.25
.24
.16

Add Health [12]CES-DChild11–19MZ_M
MZ_F
DZ_M
DZ_F
DZ_OS
141
141
131
114
197
.35
.54
.35
.21
.16

G1219 [17]MFQChild12–19MZ_M
MZ_F
DZ_M
DZ_F
DZ_OS
168
199
138
190
463
.52
.57
.33
.49
.34

MRQ: Mood and Feelings Questionnaire.
MPNI: Multidimensional Peer Nomination Inventory; CDI: Children Depression Inventory.