The M-CHAT-R/F is a 20-item yes-or-no questionnaire scored by assigning one point for each response that suggests autism risk, with a maximum possible score of 20. Most items score one point for a “no” answer, but three items (2, 5, and 12) are reverse-scored, meaning “yes” is the at-risk response. Your child’s total determines whether they fall into low, medium, or high risk categories.
How Each Item Is Scored
For 17 of the 20 questions, a “no” response earns one point because it indicates a possible concern. A “yes” response on those items earns zero points. Items 2, 5, and 12 work in the opposite direction: “yes” earns one point and “no” earns zero. These three questions are structured so that answering “yes” is the response associated with elevated autism likelihood.
Once you’ve assigned points to all 20 items, add them up. The total is your child’s M-CHAT-R score.
What the Three Risk Levels Mean
A total score of 0 to 2 places a child in the low-risk category. No further action is needed based on the screening alone, though the questionnaire can be re-administered at a later well-child visit if concerns develop.
A total score of 3 to 7 is medium risk. This does not mean your child has autism. It means a second step, called the Follow-Up Interview, is needed to clarify the flagged items. About 6% of children who take the initial questionnaire land in this range. During the Follow-Up, a clinician asks more detailed questions about the specific items your child scored on. Roughly one-third of families who complete the Follow-Up still show elevated risk and are referred for a full evaluation. The other two-thirds screen out, meaning the initial flags were not confirmed.
A total score of 8 to 20 is high risk. At this level, the Follow-Up Interview is bypassed entirely, and the child is referred directly for diagnostic evaluation and early intervention services.
Scoring Example
Suppose your child’s responses produce “no” on items 3, 6, and 14, and “yes” on item 5. Items 3, 6, and 14 are standard-scored, so each “no” earns one point (3 points). Item 5 is reverse-scored, so “yes” also earns one point (1 point). If every other response is in the low-risk direction, the total would be 4, placing the child in the medium-risk range and triggering the Follow-Up Interview.
Age Range and Accuracy
The M-CHAT-R/F was validated for children between 16 and 30 months old, though it has been used in clinical settings with children up to 48 months. A meta-analysis across multiple studies found the tool correctly identifies about 83% of children who do have autism (sensitivity) and correctly clears about 94% of children who do not (specificity). Those numbers reflect the full two-stage process, meaning the initial questionnaire plus the Follow-Up Interview when applicable.
The screening is not a diagnosis. A child who scores in the medium or high range needs a comprehensive developmental evaluation to determine whether autism or another developmental difference explains the flagged items. Some children score in the at-risk range due to language delays, hearing issues, or other conditions that share surface-level features with autism.
Quick Reference for Scoring
- Items 2, 5, and 12: “Yes” = 1 point (at risk). “No” = 0 points.
- All other items (1, 3, 4, 6–11, 13–20): “No” = 1 point (at risk). “Yes” = 0 points.
- Score 0–2: Low risk. No immediate follow-up needed.
- Score 3–7: Medium risk. Follow-Up Interview required.
- Score 8–20: High risk. Direct referral for evaluation.