Results for the survey are based on telephone interviews conducted under the direction of Princeton Survey Research Associates among a nationwide sample of 1,786 adults, 18 years of age or older, during the period March 24-30, 1999. For results based on the total sample, one can say with 95% confidence that the error attributable to sampling and other random effects is plus or minus 3 percentage points. For results based on either Form 1 (N=893) or Form 2 (N=893), the sampling error is plus or minus 4 percentage points.

In addition to sampling error, one should bear in mind that question wording and practical difficulties in conducting surveys can introduce error into the findings of opinion polls.