Table 5.
Commonly used, evidence-based measures of early ASD symptoms
| Screening tool | Age range | Completion time | Test performance | Test sample | Description |
|---|---|---|---|---|---|
| Questionnaires (parents, teachers) | |||||
| Modified Checklist for Autism in Toddlers, Revised with Follow-up (M-CHAT-R/F) (30,62) | 16–30 months | 5–10 minutes | Se: 85% (62) Sp: 91–99% PPV: 48% for ASD (20) PPV: 95% for any DD (23) |
Low-risk toddlers screened at 18- and 24-month well-child visits | Two-stage: 20-item report with a follow-up interview (5–10 minutes). Assesses protodeclarative pointing, response to name, interest in peers, showing objects of interest to parents, imitation (No cost) |
| Infant Toddler Checklist (ITC) (47,50,62) | 8–24 months | 5–10 minutes | Se: 93% (23,50) Sp: 83% PPV: 71–79% NPV: 88–99% |
9- to 24-month-olds from general population | 24 items: Evaluates gestures, eye contact, facial expressions, vocalizations (No cost) |
| Social Responsiveness Scale – 2nd edn. Preschool (SRS-2- Preschool) (30,63) | 2.5–4.5 years | 15–20 minutes | Se: 75–78% Sp: 67–96% |
442 children with and without ASD | 65 items: Measures social awareness, reciprocal social communication, social anxiety, autistic traits and preoccupations |
| Autism Spectrum Rating Scales* (64) | 2–15 years | 5–20 minutes | Se: 92% (64) Sp: 89% PPV: 91% NPV: 89% |
2,560 children normative sample | 70 items: Assesses social and communication behaviours, self-regulation; Short-form version available (15 items, for 2- to 15-year-olds) |
| Interactive clinical tool | |||||
| Screening tool | Age range | Completion time | Psychometric properties | Test sample | Description |
| Screening Tool for Autism in Two-Year-Olds* (STAT) (65) | 24–36 months | 20 minutes | Se: 92–95% (65) Sp: 73–85% PPV: 56% NPV: 97% |
71 children with an older sibling with ASD or referred for ASD concerns | Assesses communication and social behaviours; 12 observed activities during 20-minute play sessions |
| Rapid Interactive Screening Test for Autism in Toddlers* (RITA-T) (66) | 18–36 months | 10 minutes | Se: 100% (66) Sp: 84% PPV: 88% |
61 toddlers from an early childhood clinic | Differentiates toddlers with ASD and those with DD/ non-ASD |
*Training required.
DD Developmental delay; NPV Negative predictive value; PPV Positive predictive value; Se Sensitivity; Sp Specificity.