Word count alone is a weak predictor — the red flags that actually matter are qualitative: no pointing, no joint attention, and especially regression of any skill.
2
18% of children with fewer than 10 words at 18 months develop completely normal language by age 5 with zero intervention.
3
For bilingual children, always count total vocabulary across both languages — single-language screens systematically underestimate true language development.
Research Data
Predictive Accuracy of 18-Month Red Flags for Persistent Delay
Relative predictive weight of each red flag for persistent language delay at age 5. UK Millennium Cohort Study (2021).
18% of children with fewer than 10 words at 18 months had completely normal language by age 5 with no intervention — but the red flags to watch for are qualitative, not just word counts (UK Millennium Cohort Study, 2021).