How the AP-GfK Poll was conducted

Wednesday - 9/26/2012, 3:00am EDT

By The Associated Press

(AP) - The Associated Press-GfK Poll on the health care overhaul was conducted Aug. 3-13 and is based on interviews of 1,334 adults.

The national survey was conducted online by the GfK Group of Palo Alto, Calif., under the direction and supervision of the AP's polling unit and was developed with researchers at Stanford University and the University of Michigan.

The GfK Group initially contacted people using traditional telephone and mail polling methods and followed with an online interview. People chosen for the study who had no Internet access were given it for free. With a probability basis and coverage of people who otherwise couldn't access the Internet, the GfK Group online surveys are nationally representative.

Results were weighted, or adjusted, to reflect the adult population by demographic factors such as age, sex, region, race and education.

No more than 1 time in 20 should chance variations in the sample cause the results to vary by more than plus or minus 3.4 percentage points from the answers that would be obtained if all adults in the U.S. were polled.

There are other sources of potential error in polls, including the wording and order of questions.

The questions and results are available at

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