The Hawai'i portion of the National Children's Study is conducting research in the City and County of Honolulu, which encompasses all of the island of O‘ahu, including both urban and rural communities (see image below).
Island of O‘ahu
The City and County of Honolulu covers 600 square miles. The latest U.S. Census statistics show that the county has a population of 953,207 or 69.8 percent of the State of Hawai'i's total population of 1,360,301. The population in Honolulu is primarily a minority population. Only 26.6 percent is White, 43.9 percent Asian, 8.5 percent Native Hawaiian or other Pacific Islander, 4.2 percent African-American, and 16.2 percent reporting two or more races. The population of Hispanic or Latino origin, based on a U.S. Census Bureau estimate for 2009, is 8.1 percent.
In Honolulu, 84.8 percent of the persons 25 and older are high school graduates. As of 2009, there are 338,078 housing units in Honolulu and 45 percent are in multi-unit structures. In 2000, there were 286,450 households with a mean number of persons per household of 2.95. The median household income in Honolulu is $70,010 and the percent below poverty is 8.5 percent.
There are approximately 100,000 women between 18–34 years old. Most of Honolulu's population, 98 percent, is in the metropolitan area, with 2 percent in rural areas. In the period from 2004–2008, the total annual births in the City and County of Honolulu averaged between a low of 13,308 in 2005 and a high of 14,078 in 2008, according to Hawai'i State Department of Health vital statistics reports.