Socioeconomic status and the risk of suspected autism spectrum disorders among 18-month-old toddlers in Japan: a population-based study.

Fujiwara (2014) checked every 18-month-old in one Japanese city for early signs of autism. Doctors used a simple checklist at the free 18-month check-up.

They also asked moms how many years they stayed in school. Then they looked at whether moms with less school had kids who flagged for possible ASD.

Kids whose moms left school early were more likely to fail the autism screen. The link stayed strong even after the team counted money and other family facts.

In Japan’s universal health system, lower maternal education still raised the odds of a red-flag score.

Dickinson et al. (2019) and M Shama et al. (2025) also hunted early ASD markers, but they used EEG instead of parent forms. All three studies agree: you can spot risk before age two, just with different tools.

Togashi et al. (2023) and Porter et al. (2025) worked with Japanese parents of toddlers already diagnosed. They show parent training helps once ASD is known. Fujiwara (2014) adds the upstream step: find the kids whose moms may not know how to push for tests.

No clash here—Takeo widens the funnel; the others treat the kids who come through it.

If you screen in Japan, treat a failed M-CHAT at 18 months as a maybe, not a verdict. Ask the mom about her own school history; if it stopped early, schedule a follow-up sooner and use plain words. Offer paper handouts, picture guides, and free bus tickets so the next visit actually happens. You close the gap before it grows.