Four modifiable and other major risk factors for cot death: the New Zealand study.

New Zealand's high mortality rate from sudden infant death syndrome (SIDS) prompted the development of the New Zealand Cot Death Study. A report of the analysis of the data from the first year has been published. This report now gives the major identified risk factors from the full 3 year data set. In this case-control study there were 485 infants who died from SIDS in the post-neonatal age group, and 1800 control infants, who were a representative sample of all hospital births in the study region. Obstetric records were examined and parental interviews were completed in 97.5% and 86.9% of subjects, respectively