The name is absent

Autism prodrome 84 of 89

Table 2

Prospective screening studies

Reference

Age

(Months)

Study design

Administration

Key items/content

Instrument parameters

Baron-Cohen
et al. (1992,
1996);

Baird et al.

(2000)

CHAT

18m

High risk sibling design; 2-stage
population screening (n = 16,235)

Parental questionnaire and
health practitioner
observation

Joint attention; pretend play

Sensitivity = 38% (1-stage)

Positive predictive value =
26% (1-stage); Positive
predictive value = 83% (2-
stage)_______________________

Willemsen-
Swinkels et
al. (2006);
Dietz et al.

(2006)

ESAT

14m

2-stage population screening (n =

31,724)

Health practitioner
completes items following
interview with parents

Initial screen: play, emotional
expressions, sensory oddities;
Follow-up screen: above plus
early social communication
behaviors_____________________

Positive predictive value for
ASD = 25% (2-stage);

Positive predictive value for
all neurodevelopmental
disorders = 68% (2-stage)