RR represents summary statistic from meta-analysis by Gandini et al., 2005 [20–22] (I, II, and III) or median of RR range where summary statistic is not reported. Expected ratio of incidence rates (NHW/Hispanic) based on prevalence of risk factor in each population and RR provided. Median prevalence value is used when a range is provided. CTP: California Twin Program; prevalence data for NHWs is described by Cockburn et al., 2007 [16], and prevalence data for Hispanics comes from the same data set. ~Expected rate ratio cannot be calculated because prevalence in Hispanics is unknown.