Recording of Neonatal Seizures in Birth Certificates, Maternal Interviews, and Hospital Discharge Abstracts in a Cerebral Palsy Case-Control Study in Michigan.

We evaluated the recording of neonatal seizures in birth certificates, hospital discharge abstracts, and maternal interviews in 372 children, 198 of them with cerebral palsy, born in Michigan hospitals from 1993 to 2010. In birth certificates, we examined checkbox items "seizures" or "seizure or serious neurologic dysfunction"; in hospital discharge abstracts ICD-9-CM codes 779.0, 345.X, and 780.3; and in maternal interviews a history of seizures or convulsions on day 1 of life recalled 2-16 years later. In 27 neonates, 38 neonatal seizures were recorded in 1 or more sources, 17 in discharge abstracts, 20 in maternal interviews, but just 1 on a birth certificate. The kappa coefficient (κ) between interviews and discharge abstracts was moderate (κ = 0.55), and substantial (κ = 0.63) if mothers noted use of antiepileptics. Agreement was higher (κ = 0.71 vs κ = 0.29) in term births than in preterm births. Birth certificates significantly underreported neonatal seizures.