Sampling
The 2006 Louisiana Health and Population Survey relies on a two-stage cluster sample design in which n block clusters are selected and k housing units (HU) are sampled in each block cluster. Block clusters are geographic areas composed of one or more census blocks. The U.S. Census Bureau creates block clusters based on the number expected housing units (i.e. number of housing units recorded during the 2000 Census). The Census Bureau randomly selects a predetermined number of block clusters within each parish - 80 block clusters in urban parishes and 55 block clusters in rural parishes. In the case of Orleans Parish, a geographic stratification was made to separate the East Bank from the West Bank of the Mississippi River and within the East Bank a stratification was made to separate generally flooded from generally un-flooded areas.