Results for the July 2004 Foreign Policy and Party Images survey are based on telephone interviews conducted under the direction of Princeton Survey Research Associates International among a nationwide sample of 2,009 adults, 18 years of age or older, during the period July 8-18, 2004. For results based on the total sample, one can say with 95% confidence that the error attributable to sampling is plus or minus 2.5 percentage points. For results based on either Form 1 (N=1003) or Form 2 (N=1006) general public, the sampling error is plus or minus 3.5 percentage points.
In addition to sampling error, one should bear in mind that question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of opinion polls.