Sampling
...were selected with probability proportional to size. Target population Total usually resident, non-institutionalised, civilian population of New Zealand aged 15 years and over. Sampled areas North Island, South Island and Waiheke Island. Areas excluded Offshore islands other than Waiheke Island. PSUs containing fewer than nine dwellings were also excluded. Dwellings included Permanent, private dwellings. Dwellings excluded Temporary private dwellings. Non-private dwellings. Eligible respo...