"The public needs to have more and better education about genetics," said Eleanor Singer, lead author of the study and a senior research scientist at the U-M Institute for Social Research (ISR), the world's largest academic survey and research organization.
For the study, Singer and ISR colleagues Toni Antonucci and John Van Hoewyk compared data from a random-digit-dialed national survey of 1,006 respondents conducted in 1990 with data from later national surveys, including a random-digit-dialed survey of 1,824 respondents conducted in 2000.
The topics included attitudes toward prenatal testing, abortion, genetic testing in the workplace, genetic testing for adult-onset untreatable diseases and a series of true-or-false statements that they used to construct an "accuracy index."
Comparing the number of accuracy-index questions answered correctly in 1990 and 2000, the researchers found that even after controlling for demographic characteristics of the respondents including age and education, the proportion of questions answered correctly was significantly lower in 2000 than it had been in 1990.
In 1990, for example, 58 percent of those surveyed correctly answered at least three out of five accuracy-index questions, compared to just 24 percent in 2000. (See table for proportions answering knowledge questions correctly, by year)
The questions included whether genetic testing can detect a tendency to develop certain types of cancer and depression; whether it can be used during pregnancy to find out if the baby or fetus will develop certain diseases; and whether gene therapy can be used to correct defects discovered through prenatal testing. Because of changes in expert knowledge about genetics and genetic testing, the wording of the questions used to measure accuracy changed slightly between the two years. (See table for question wording) But while the question wording changed slightly, the difficulty level of the questions was similar.
The following statement, part of the accuracy index, appeared in identical form in both the 1990 and 2000 surveys: "Genetic screening can be used in adults to predict whether a person will suffer a heart attack." Fifty-five percent of the adults surveyed in both years correctly said that the statement was false. "In other words," Singer said, "as measured by responses to this question, accuracy was not much better than chance in either year."
In addition to gauging the accuracy of public knowledge, the study compared how attitudes toward prenatal testing, preferences for abortion in case of fetal defect and attitudes toward genetic testing in the workplace had changed---or remained the same---over time.
In both 1990 and 2000, about two-thirds of respondents said that if they or their partner were pregnant, they would want to have prenatal testing to see if the baby had any serious genetic defects.
But attitudes toward abortion in case of fetal defect changed considerably over the 10-year period, Singer found, with a much smaller percentage reporting that they would have an abortion if a prenatal test showed a serious defect---22 percent in 2000 compared to 32 percent in 1990.
On May 15 at the annual meeting of the American Association of Public Opinion Research, Singer and Antonucci will present data from the same surveys showing how these attitudes and beliefs were related to demographic factors, including race and ethnicity. In general, they found that African-American and Latino respondents were more likely than whites to favor both prenatal and adult genetic testing.
About 76 percent of Blacks, 74 percent of Latino and 66 percent of whites surveyed in 2000 said they would want a test to find out if their baby had any serious genetic defects. "At the same time, African-Americans and Latinos have lower than average income than whites, and are less likely to carry private health insurance," said Singer. "Thus, their ability to avail themselves of genetic testing is reduced relative to whites." In addition, the researchers found that Blacks and Latinos are more concerned than whites with possible misuses of genetic information.
Established in 1948, the Institute for Social Research (ISR) is among the world's oldest survey research organizations, and a world leader in the development and application of social science methodology. ISR conducts some of the most widely-cited studies in the nation, including the Survey of Consumer Attitudes, the National Election Studies, the Monitoring the Future Study, the Panel Study of Income Dynamics, the Health and Retirement Study, the Columbia County Longitudinal Study and the National Survey of Black Americans. ISR researchers also collaborate with social scientists in more than 60 nations on the World Values Surveys and other projects, and the Institute has established formal ties with universities in Poland, China, and South Africa. Visit the ISR Web site at www.isr.umich.edu for more information. ISR is also home to the Inter-University Consortium for Political and Social Research (ICPSR), the world's largest computerized social science data archive.
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