Table 4.
Prevalence of ASD in Chinese children aged 6 to 12 years (per 100).
| Category | Sample size | ASD cases | Observed prevalence (95% CI) | Estimated prevalence (95% CI) |
|---|---|---|---|---|
| Sex | ||||
| Male | 66,687 | 292 | 0.44 (0.38, 0.49) | 0.95 (0.87, 1.02) |
| Female | 59,119 | 71 | 0.12 (0.09, 0.15) | 0.30 (0.26, 0.34) |
| Age (years) | ||||
| 6 | 15,070 | 43 | 0.29 (0.20, 0.37) | / |
| 7 | 21,574 | 69 | 0.32 (0.24, 0.40) | / |
| 8 | 17,796 | 61 | 0.34 (0.26, 0.43) | / |
| 9 | 17,759 | 44 | 0.25 (0.17, 0.32) | / |
| 10 | 19,475 | 65 | 0.33 (0.25, 0.41) | / |
| 11 | 16,891 | 36 | 0.21 (0.14, 0.28) | / |
| 12 | 17,241 | 45 | 0.26 (0.18, 0.34) | |
| Total | 125,806 | 363 | 0.29 (0.26, 0.32) | 0.70 (0.64, 0.74) |
| ASD case status | ||||
| Newly diagnosed | / | 157 (43.3) | / | |
| Previously diagnosed | / | 206 (56.7) | / |
ASD, autism spectrum disorder; CI, confidence interval. The estimated prevalence of ASD was higher in boys than in girls (P < 0.001) and did not differ among ages (χ2 = 8.76, df = 6, P = 0.19).