Results for the survey are based on telephone interviews conducted under the direction of Princeton Survey Research Associates among a nationwide, representative sample of 967 adults, 18 years of age or older, in France, 944 adults in Germany, 1000 adults in Italy, 1000 in Britain and 1277 adults in the U.S. The fieldwork was conducted by Taylor Nelson Sofres in France between August 2 and 7, Emnid in Germany between August 6 and 7, Pragma in Italy between August 6 and 9, NOP in Britain between August 1 and 6, and Princeton Data Source in the U.S. between August 2 and 8. For results based on the total sample in each of the five countries, one can say with 95% confidence that the error attributable to sampling and other random effects is plus or minus 3.5 percentage points for each of the European countries, plus or minus 3 percentage points for the United States.
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.
