“…Underdiagnosis may help explain this discrepancy because an earlier study found comparable rates of SIDS in Brazil and the United States, after adjusting for underdiagnosis (Nunes et al, 2001). On the other hand, a recent study using death certificates found much lower rates of SIDS in Brazil compared with the United States, suggesting that underdiagnosis may still contribute to Brazil's lower rates (Woida, Saggioro, Ferro, & Peres, 2008). Table 1 and for maternal smoking prevalence are from the confidence intervals of the estimates.…”