[Skip to Navigation]
Comment & Response
March 2016

Sibling Comparisons and Confounding in Autism Epidemiological Studies

Author Affiliations
  • 1Department of Public Health, Section of Epidemiology, Aarhus University, Aarhus, Denmark
  • 2Department of Economics and Business, National Centre for Register-based Research, Aarhus University, Aarhus, Denmark
  • 3Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, Aarhus, Denmark
  • 4Department of Public Health, Section for Biostatistics, Aarhus University, Aarhus, Denmark
JAMA Psychiatry. 2016;73(3):302-303. doi:10.1001/jamapsychiatry.2015.2661

To the Editor Based on a discordant sibling analysis, Curran et al1 concluded that the elevated risk for autism spectrum disorder (ASD) from cesarean section (CS) was explained by familial factors. Sibling designs are applied to control for unmeasured confounders believed to have a significant influence on outcome apart from the primary exposure under investigation. While the design accounts for confounding from unmeasured shared familial factors, it may open a “backdoor” for confounding from unshared factors.

Add or change institution