Incidence Risk Ratio of Specific Diagnoses of Autism Spectrum Disorders in Relation to Individual and Parental Diagnosis of Obsessive-compulsive Disorder (OCD; 1994–2012).

aMaternal or paternal diagnoses were categorized hierarchically as having a history of OCD, autism spectrum disorders or other psychiatric disorders. Estimates of relative risk were adjusted for calendar year, age, maternal and paternal age, sex, place of residence at time of birth and the interaction of age with sexbEstimates of relative risk were adjusted for calendar year, age, maternal and paternal age, sex, parental history of psychiatric illness, first psychiatric hospital contact for any other disorder, place of residence at time of birth and the interaction of age with sexIncidence Risk Ratio of Specific Diagnoses of Autism Spectrum Disorders in Relation to Individual and Parental Diagnosis of Obsessive-compulsive Disorder (OCD; 1994–2012).