Table 1 Factor loadings for the items included (bold) in the outcome measures at age 3 years

Demands must be met immediately

.70

.27

.13

.18

Defiant

.65

.15

.13

.10

Gets in many fights

.62

.08

.10

.23

Can’t stand waiting. wants everything now

.62

.25

.10

.36

Gets into everything

.52

.13

.09

.26

Hits others

.49

.02

.08

.21

Resists going to bed at night

.42

.13

.36

-.08

Punishment doesn’t change his/her behaviour

.42

.13

.23

.39

Sudden changes in moods and feelings

.41

.25

.25

.26

Too fearful or anxious

.10

.64

.28

.09

Afraid to try new things

-.03

.60

.14

.08

Clings to adults or are too dependent

.30

.59

.21

.13

Disturbed by any change in routine

.27

.55

.15

.16

Gets too upset when separated from parents

.16

.54

.19

.03

Doesn’t eat well

.17

.13

.75

.13

Doesn’t seem to be happy eating food (exc. sweets)

.13

.11

.71

.23

Stomach aches or cramps (without medical cause)

.14

.20

.43

.06

Doesn’t want to sleep alone

.31

.23

.37

-.18

Constipated, doesn’t move bowels

.02

.19

.36

-.01

Vomiting, throwing up (without medical cause)

.01

.14

.28

.13

Can’t concentrate, can’t pay attention for long

.25

.16

.11

.72

Can’t sit still, restless or overactive

.34

.09

.12

.67

Quickly shifts from one activity to another

.39

.12

.17

.53

Poorly coordinated or clumsy

.00

.33

.13

.35

Doesn’t seem to feel guilty after misbehaving

.14

.09

.11

.33

Eats and drinks things that are not food (not sweets)

.16

.10

.16

.31