Table 2 Characteristics of children with parent-reported ASD diagnosis (n=291) by cohort
ALSPAC
1997/1998
Total n=82
MCS
2007/2008
Total n=209
Test of difference
OR (95% CI)
P
Female, %26180.95 (0.89–1.01)0.12
Age at diagnosisa early (<5 years), %72600.56 (0.27–1.18)0.13
  • ASD, autism spectrum disorder; ALSPAC, Avon Longitudinal Study of Parents and Children; MCS, Millennium Cohort Study.

  • a 29 ALSPAC parents did not give date of ASD diagnosis: 53 records available.