Percentages reported in the text and tables are weighted, while the number of cases shown in the tables for various subgroups is the actual number of respondents. Questions answered by the sample of 809 adults are subject to a sampling error of plus or minus approximately 4 percentage points at the 95 percent level of confidence. This means that in 95 out of 100 samples like the one used here , the results obtained should be no more than 4 percentage points above or below the figure that would be obtained by interviewing all Virginia adults with telephones. Where the answers of subgroups are reported, the sampling error would be higher. Sampli ng error for the 317 parents in the survey is plus or minus approximately 6 percentage points.
Surveys are also subject to errors from sources other than sampling.
While every effort is made to identify such errors, they are often difficult or impossible to measure. Readers making use of the results a re urged to be mindful of the limitations inherent in survey research.