Autism tests › SACS-R
SACS-R: surveillance instead of a single screen
Most tools on this site are a questionnaire filled in once. The Social Attention and Communication Surveillance–Revised takes the opposite approach: trained nurses watch a small set of specific social behaviors repeatedly, at every routine check from 12 months on. The results are among the strongest early-detection data anywhere.
| Type | Developmental surveillance — repeated professional observation, not a parent questionnaire |
|---|---|
| Ages monitored | 12, 18 and 24 months (SACS-R), plus 3.5 years (SACS-PR) |
| Who administers | Trained maternal and child health nurses during routine well-child checks |
| Origin | Josephine Barbaro and colleagues, Olga Tennison Autism Research Centre, La Trobe University, Australia |
| Where used | Rolled out across parts of Australia; trialled and adapted in several other countries |
What the nurses watch for
The markers are exactly the ones on the signs-by-age page, which is not a coincidence — this is the research those markers come from: eye contact, response to name, pointing (both to request and to show), showing objects, gestures, imitation, shared enjoyment, and pretend play. What makes SACS-R different is that a professional observes them directly, and does so again a few months later.
The accuracy figures — including the part that matters most
83%
Positive predictive value at 12–24 months: when SACS-R flagged a child, that flag was right about 83% of the timeBarbaro et al., JAMA Network Open, 2022
99.6%
Specificity — children who are not autistic are almost never flaggedBarbaro et al., 2022
62%
Sensitivity — roughly four in ten autistic children were not flagged by 24 monthsBarbaro et al., 2022
Read those three numbers together, because they tell the real story. SACS-R is remarkably good at not raising false alarms: a flag means something, and the families who get one are overwhelmingly families who needed to hear it. But its sensitivity is modest — a substantial share of autistic children pass through unflagged in the first two years, which is why surveillance continues at 3.5 years and why no negative result, from any instrument on this site, should ever override a parent's persistent concern. That is not a criticism of SACS-R; it is the honest shape of early detection, and most tools simply don't publish the number this clearly.
Why this matters even if you don't live in Australia. SACS-R is the best available evidence for a claim this site makes throughout: identification depends less on the perfect questionnaire than on whether someone systematically looks, more than once. In systems without such a program — which is most of them — that repeated looking has to come from somewhere else. Usually it comes from you, and from asking for screening at each visit rather than assuming it happened. See how screening works.
Sources
- Barbaro J, Sadka N, Gilbert M, et al. Diagnostic Accuracy of the Social Attention and Communication Surveillance–Revised With Preschool Tool for Early Autism Detection in Very Young Children. JAMA Netw Open 2022;5(3):e2146415. pubmed.ncbi.nlm.nih.gov/35275169
- Olga Tennison Autism Research Centre, La Trobe University — SACS-R program information. latrobe.edu.au/otarc
Medical disclaimer: Educational information only. SACS-R and SACS-PR belong to their authors and institution. This page cannot diagnose your child; consult a qualified clinician.