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Chapter 7. Science and Technology: Public Attitudes and Understanding

Public Attitudes About Specific S&T-Related Issues

Public attitudes can affect the speed and direction of S&T development. When science plays a substantial role in a national policy controversy, more than the specific policies under debate may be at stake. The policy debate may also shape public opinion and government decisions about investments in general categories of research. Less directly, a highly visible debate involving S&T issues may shape overall public impressions of either the credibility of science or the proper role of science in other, less visible public decisions.

Likewise, public attitudes about emerging areas of research and new technologies may have an influence on innovation. The climate of opinion concerning new research areas can influence levels of public and private investment in related technological innovations and, eventually, the adoption of new technologies and the growth of industries based on these technologies.

For these reasons, survey responses regarding controversies over policies involving science, specific research areas, and emerging technologies are relevant. In addition, responses about relatively specific matters provide insight into the practical decisions through which citizens translate more general attitudes into actions, although, like all survey responses, how these responses relate to actual behavior remains uncertain. More generally, even in democratic societies, public opinion about new S&T developments does not translate directly into actions or policy. Instead, it filters through institutions that selectively measure what the public believes and either magnify or minimize the effects of divisions in public opinion on public discourse and government policy (Jasanoff 2005). Public attitudes about specific S&T issues can differ markedly from the views of scientists. (See sidebar, "Differences Between Scientists and the Public on S&T-related Issues.")

Public attitudes toward policy issues involve a multitude of factors, not just knowledge or understanding of relevant science. Values, morals, judgments of prudence, and numerous other factors can come strongly into play; judgments about scientific fact are often secondary. In assessing the same issue, different people may find different considerations relevant.

This section discusses data on environmental issues, including global climate change, nuclear power, and energy development; cloning and stem cell research; teaching evolution in schools; agricultural biotechnology (i.e., GM food); and attitudes toward recent and novel technologies, including nanotechnology and medical biotechnology. It concludes with recent data on attitudes toward scientific research on animals and toward science and mathematics education.

Environment, Climate Change, and Energy Development

Environmental issues, such as climate change, and the closely related issue of sustainable energy sources, have become of increased salience in national policy debates and international meetings such as those at the United Nations Climate Change Conference, held in Copenhagen, Denmark in December 2009. For Americans, the April 2010 oil spill in the Gulf of Mexico further increased the salience of environmental issues—particularly the environmental hazards of offshore oil drilling—with long-running media coverage and sustained public attention (Pew Research Center 2010c).

Surveys taken shortly after the oil spill in the Gulf found increased willingness to trade off energy production for environmental protection when compared with surveys conducted before the oil spill (Jones 2010). In addition, there was decreased public support for offshore oil drilling shortly after the spill; since that time, public support has returned to previous levels (Pew Research Center 2010b).

Concern About Environmental Quality

The Gallup Organization's annual survey on environmental issues indicates that Americans were somewhat less concerned about environmental quality in 2010 and early 2011, after an increase in expressed concern between 2006 and 2008. The 2011 Gallup Poll found 34% of Americans worry "a great deal" about the environment, 34% worry "a fair amount," and 31% worry "only a little" or "not at all" (Saad 2011a).[35] The percentage saying they worry "a great deal" was the same in 2010 (figure 7-16). Relative to other concerns, environmental quality ranked lower on the list than a number of other concerns including the economy (71%) and federal spending and the budget deficit (64%).

Environmental concerns are infrequently mentioned in response to open-ended questions about the most important problems facing the nation. Only about 2% of Americans mentioned the environment or pollution in an open-ended question asking "What do you think is the most important problem facing this country today?" (Jones 2011c).

Climate Change

Climate change (often colloquially referred to as global warming), has become a prominent environmental issue for the American public. In a 2008 survey asking Americans to report, in their own words, the "single biggest environmental problem the world faces at this time," the most common response was climate change (25%), followed by pollution (24%), energy problems (11%), and toxic substances in the environment (6%) (ABC News 2008).

Other surveys, using structured questions, also show evidence of widespread awareness of the issue of climate change. The Gallup Polls registered gradual increases in the percentage of Americans who say they understand the "global warming" issue "very well" or "fairly well," from 68% in 2004 to 82% in 2010 (The Gallup Organization 2010).

Public debate about climate change has centered on both the existence of climate change and the likely causes of any change occurring. Gallup surveys found a decline in the percentage of Americans who consider climate change to be primarily due to human activities. When asked whether "the increases in the earth's temperature over the last century" are largely the result of human activities rather than natural changes, half of Americans said human activities in 2010, down 8 points from 2008, and 46% said natural changes (Newport 2010).[36]

A large number of surveys have been conducted about climate change, both in the United States and abroad. The Pew Global Attitudes survey conducted in 2010 among 22 nations found 37% of Americans consider global climate change a "very serious problem," one third said it was "somewhat serious," and a minority said it was "not too serious" (15%) or "not a problem" (13%). The percentage of Americans saying climate change is "very serious" decreased 10 points from 47% in 2007. Americans express less concern about climate change than individuals in a number of other countries where majorities consider climate change a very serious problem: Germany, Japan, South Korea, India, Kenya, Argentina, Brazil, Mexico, Lebanon, and Turkey. Half or near half of the citizens in Spain, Jordan, and Indonesia say the same. The Chinese and British are about equally likely as Americans to say climate change is a very serious problem (41% and 40%, respectively). The only publics with lower concern than Americans about climate change were those in Poland (31%) and Pakistan (22%). A World Public Opinion survey conducted in 2009 in 15 nations found a similar pattern, with Americans, Russians, and Chinese least likely to consider climate change a "very serious" problem.

Assessment of Potential Problems

Public assessments of the degree to which potential hazards pose a threat to the environment have been surprisingly stable over the past two decades. A series of questions on the GSS surveys conducted in 1993, 1994, 2000, and 2010 show that Americans consider pollution of America's rivers, lakes, and streams to be more dangerous to the environment than any of several other potential problems; in 2010, 69% considered water pollution to be very or extremely dangerous. Air pollution caused by industry was considered very or extremely dangerous to the environment by 63%, whereas air pollution caused by cars was less likely to be considered very or extremely dangerous to the environment (43%) (table 7-17).

Furthermore, 48% of Americans considered the "rise in temperature caused by climate change" to be very or extremely dangerous to the environment, according to the 2010 GSS. A decade earlier, that figure was 40%. The percentage saying that climate change was not very or not at all dangerous to the environment rose during the same period, from 11% in 2000 to 18% in 2010. The percentage holding no opinion decreased during the same period.

Nuclear power stations were considered very or extremely dangerous to the environment by 45% of Americans in 2010. Perceptions of environmental danger from nuclear power stations were about the same as when this question was first asked in 1993. However, it is important to note that these data were collected prior to concerns about the risk to human health and the environment from damage to nuclear energy plants in the aftermath of the earthquake and tsunami in Japan in March 2011.

Assessments of environmental dangers changed substantially on only one issue—pesticides and chemicals used in farming. About half of Americans (52%) called these very or extremely dangerous to the environment in 2010, up from 45% in 2000 and 37% in 1993.

Concern about environmental dangers from GM crops appears to be modest. In the 2010 GSS, a quarter of Americans said modifying the genes of crops is very or extremely dangerous to the environment, and a roughly equal portion (26%) said this is not very or not at all dangerous to the environment. Another 16% of Americans held no opinion about the dangers of GM crops, suggesting that the public has a more limited awareness or understanding of this issue.

Nuclear Power and Other Energy Sources

Public debate about energy sources in recent years has emphasized the need for lessened U.S. reliance on imported oil and more focus on alternative, renewable energy sources. A Gallup/USA Today poll conducted in early 2011 found more than eight in ten (83%) Americans favor legislation that "provides incentives for using solar and other alternative energy sources," and 15% are opposed. Two-thirds favor legislation that "expands drilling and exploration for oil and gas" (Jones 2011b). These findings are in keeping with public preferences on government spending in the 2010 GSS survey; 61% of Americans said the government is spending "too little" on developing alternative sources of energy.

Support for nuclear energy has varied over the past 15 years. American public opinion was fairly evenly divided in the late 1990s and support increased in the late 2000s. According to the 2010 GSS, about six in ten (61%) Americans favor or strongly favor increasing the use of nuclear energy to generate electricity in the United States, about three in ten (28%) oppose or strongly oppose, and the remainder gave no opinion. Similarly, the proportion of Americans who favor the use of nuclear power as "one of the ways to provide electricity" ranged from 57% to 62% between 2009 and early 2011 on Gallup surveys (Jones 2011a). The 2011 survey was conducted prior to damage to nuclear energy plants in Japan stemming from the earthquake and tsunami in March 2011. A Pew Research Center survey conducted shortly after the disaster in Japan suggests that Americans' support for nuclear power declined, but the long-term effect on Americans' attitudes toward nuclear power is unknown at this time (Pew Research Center 2011c). A substantial minority of Americans (42%) said nuclear power plants are not safe in a 2009 Gallup Poll, and prior surveys indicate that three out of five Americans oppose the construction of a nuclear energy plant in their local communities (Jones 2009).[37]

International Comparisons

In 2010, Europeans were divided about whether or not nuclear energy will "improve our way of life" (39%) or "make things worse" (39%). The remainder said nuclear energy will have no effect (10%) or held no opinion (13%). Assessments of nuclear energy were more negative when this question was first asked in 1999, and have been increasingly divided since that time (EC 2010). Support for nuclear energy varies a great deal among European countries. In general, citizens of countries that have operational nuclear power plants are considerably more likely to support nuclear energy than citizens of other countries (see NSB 2010).[38]

Stem Cell Research and Human Cloning

Unlike many issues involving scientific research, studies using embryonic stem cells have generated considerable public controversy. In the case of stem cell research, many people's attitudes are strongly related to their views about moral fundamentals. There is less reason to believe that this is the case for other S&T issues, such as nuclear power.

Public support for "medical research that uses stem cells from human embryos" grew over the past decade, from a low of 35% in favor in 2002. Since 2004, a majority of the public has favored stem cell research, with 62% favoring in 2010 and 31% opposed (VCU 2010) (figure 7-17). Annual Gallup Poll data draw a similar picture: the percentage of Americans who find stem cell research "morally acceptable" has fluctuated from a low of 52% in 2002 to a high of 64% in 2007; in 2011, 62% said it was "morally acceptable" and 30% said it was "morally wrong" (Saad 2011b).

Support for stem cell research is greater when the question posed asks about research that uses stem cells from sources that do not involve human embryos. About seven out of ten respondents (71%) favored this type of research in 2010, down slightly from 75% in 2007 (VCU 2010). Support is also greater when the question is framed as an emotionally compelling personal issue ("If you or a member of your family had a condition such as Parkinson's Disease, or a spinal cord injury, would you support the use of embryonic stem cells in order to pursue a treatment for that condition?") In this case, 70% of Americans support treatments that use stem cells and 21% do not (VCU 2006).

Americans are overwhelmingly opposed to human cloning when there is no mention of a medical purpose. In a 2010 survey, the idea of cloning or genetically altering humans was rejected by eight in ten Americans (VCU 2010,). Opinions are more mixed when questions mention "cloning technology" that is used only to help medical research develop new treatments for disease; opinion about therapeutic cloning has been slowly growing more positive in recent years, with 55% in favor and 40% opposed in 2010 (table 7-18). The specter of reproductive cloning can generate apprehension about therapeutic cloning. Asked how concerned they were that "the use of human cloning technology to create stem cells for human therapeutic purposes will lead to a greater chance of human reproductive cloning," more than two-thirds of Americans said they were either very (31%) or somewhat (38%) concerned (VCU 2006).

Public attitudes toward cloning technology are not grounded in a strong grasp of the difference between reproductive and therapeutic cloning (see Glossary for definitions.) In the 2008 VCU survey, most Americans (64%) said they were "not very clear" or "not clear at all" about this distinction, with 26% saying they were "somewhat clear" and only 8% characterizing themselves as "very clear" about it. The number of Americans who professed greater comprehension in 2008 was lower than it was when VCU began asking this question in 2002. Additionally, self-assessed understanding of stem cell research declined between 2008 and 2010. In 2010, a 54% majority of Americans were "very clear" or "somewhat clear" about the difference between stem cells that come from human embryos, stem cells that come from adults, and stem cells that come from other sources, down from 64% in 2008 (VCU 2010).

An international survey on attitudes toward stem cell research in a dozen European countries, the United States, Japan, and Israel found that awareness, knowledge, and attitudes about this type of research vary widely (Fundacion BBVA 2008). Overall, Americans were more aware of stem cell research than residents of most other countries and more often responded correctly to knowledge questions on this subject. All the same, Americans were somewhat more likely than residents of several countries in Europe to believe that stem cell research is immoral (appendix table 7-32).

Teaching Evolution in the Schools

In the United States, the topic of whether and how evolution should be taught in the school system has been a frequent source of controversy for almost a century. Public views about evolution and the role of teaching evolution in the schools have been relatively stable over the course of 30 years. In surveys sponsored by NSF between 1979 and 2010, many Americans appear skeptical of established scientific ideas about evolution. For example, when asked about the statement "human beings, as we know them today, developed from earlier species of animals" on the 2010 GSS survey, 38% considered this statement false and 47% said it was true (appendix table 7-10).

An experimental study included in the 2004 Michigan Survey of Consumer Attitudes suggests that survey responses to such questions reflect more than unfamiliarity with basic elements of science. Some of the survey respondents were asked a question that tested knowledge about evolution ("human beings, as we know them today, developed from earlier species of animals"). Other respondents were asked a question about what the theory of evolution asserts ("according to the theory of evolution, human beings, as we know them today, developed from earlier species of animals"). Respondents were much more likely to answer correctly if the question was framed as being about scientific theories rather than as being about the natural world. When the question about evolution was prefaced by "according to the theory of evolution," 74% responded that the statement was true; conversely, only 42% considered the statement true when it was not prefaced as such. (For more details, see NSB 2008.) These differences may indicate that many Americans hold religious or other beliefs that cause them to be skeptical of certain established scientific ideas, even when they have some basic familiarity with those ideas.

When surveys ask for opinions about whether and how evolution should be taught in U.S. public schools, two key patterns emerge. First, when asked whether creation should be taught alongside of or in addition to evolution, a majority of Americans favor this pluralistic approach to education. Second, when asked whether creation should be taught instead of evolution—thereby replacing it in the science curriculum—a majority oppose this idea, while a sizeable minority favor it. In the most recent survey, 49% opposed teaching creation instead of evolution in the public schools and 38% favored it (Plutzer and Berkman 2008; Berkman and Plutzer 2010).

Genetically Modified Food

Although the introduction of GM crops has provoked much less public controversy in the United States than in Europe, U.S. public support for this application of biotechnology is limited. According to a 2008 CBS/New York Times poll, 44% of Americans indicate they have heard nothing or "not much" about GM ingredients added to foods to make them taste better and last longer (CBS-NYT 2008). However, 87% believe that these foods should be labeled and 53% expect that it is "not very likely" or "not at all likely" that they would buy food that is labeled as such.

Overall, these results are consistent with a series of five surveys conducted by the Pew Initiative on Food and Biotechnology between 2001 and 2006. These studies consistently found that only about one-fourth of U.S. consumers favor "the introduction of genetically modified foods into the U.S. food supply" (Mellman Group, Inc. 2006). The percentage of U.S. survey respondents reporting a negative reaction to the phrase "genetically modified food" (44%) was more than twice the 20% that reported a positive reaction (Canadian Biotechnology Secretariat 2005). Nonetheless, consumers in the United States express more favorable views than Europeans, with Canadians falling somewhere in between (Gaskell et al. 2006).

Although the FDA proposed guidelines for the approval process for genetically engineered animals in September 2008 (Maugh and Kaplan 2008), past surveys have generally found that U.S. residents are even more wary of genetic modification of animals than they are of genetic modification of plants (Mellman Group, Inc. 2005). Many express support for regulatory responses, but this support appears to be quite sensitive to the way issues are framed. Thus, whereas 29% expressed a great deal of confidence in "the Food and Drug Administration or FDA," only about half as many expressed the same confidence when the question was posed about "government regulators" (Mellman Group, Inc. 2006). (Additional findings from earlier U.S. surveys can be found in NSB 2006 and NSB 2008.)

Nanotechnology

Nanotechnology involves manipulating matter at unprecedentedly small scales to create new or improved products that can be used in a wide variety of ways. Nanotechnology has been the focus of relatively large public and private investments for almost a decade, and innovations based on nanotechnology are increasingly common. However, relative to other new technologies, nanotechnology is still in an early stage of development and the degree of risk remains uncertain (Chatterjee 2008, Barlow et al. 2009).

As noted earlier, public awareness and understanding of nanotechnology remains limited despite increased federal funding and more than 600 nanotechnology products already on the market (The National Academies 2008a).[39] According to the 2010 GSS, 24% of Americans report having heard "a lot" or "some" about nanotechnology, up four percentage points from 2008 and 2006. A plurality (44%) of Americans report having heard "nothing at all" about nanotechnology (appendix table 7-33). In 2010, among the minority of respondents who had heard "a lot" or "some" about this technology, 65% correctly indicated that "nanotechnology involves manipulating extremely small units of matter, such as individual atoms, in order to produce better materials," and 39% correctly indicated that "the properties of nanoscale materials often differ fundamentally and unexpectedly from the properties of the same materials at larger scales."

After receiving a brief explanation of nanotechnology, GSS respondents were asked about the likely balance between the benefits and harms of nanotechnology. Among all respondents to the 2010 GSS, regardless of their awareness of nanotechnology, 37% said the benefits will outweigh the harmful results, 11% expected the harms to predominate, and 43% held no opinion (appendix table 7-34). The balance of opinion was similar in 2006 and 2008.

In the GSS data, favorable attitudes toward and familiarity with nanotechnology are strongly associated. That is, Americans who say they are more familiar with nanotechnology are more likely to believe that its benefits will outweigh the risks. Among those who have heard "a lot" or "some" about nanotechnology, 65% said the benefits will outweigh the harms, 8% said harmful results will outweigh any benefits, 5% said benefits and harms would be about equal, and 22% had no opinion.[40] However, this association does not mean that when people become more familiar with nanotechnology their attitudes necessarily become positive (Cobb 2005; Lee, Scheufele, and Lewenstein 2005). Furthermore, recent research suggests that attitudes toward nanotechnology are likely to vary depending on the context in which it is applied, with energy applications viewed much more positively than those in health and human enhancements (Pidgeon et al. 2009).

International Comparisons

In Europe, 45% of survey respondents said they had heard of nanotechnology on the 2010 Eurobarometer, which described nanotechnology in terms of consumer product applications. Overall, 44% of Europeans agreed that nanotechnology should be encouraged, 35% disagreed, and 22% had no opinion about this issue (Gaskell et al. 2010).

Other Emerging Technologies

Opinions on other new and emerging technologies show an often receptive public, but one where opinion is likely to be fluid due to low levels of familiarity with the issue and any relevant concerns for public debate.

Synthetic biology, an emerging field that applies biologic science to design and construct new biological parts, organisms, or artificially engineered biological systems, provides one example. About one-quarter (26%) of Americans have heard "some" or "a lot" about synthetic biology, up from 9% in 2008 (Peter D. Hart Research Associates, Inc. 2010). When first asked to weigh the benefits and harms from synthetic biology, one-third thought the benefits and risks would be about equal, a similar percentage had no opinion, and the remainder was split about equally between those who felt the benefits would outweigh the risks and those who felt the risks would outweigh the benefits. After hearing a balanced description of the benefits and risks of synthetic biology, a greater proportion said the risks will outweigh the benefits than said the benefits will outweigh the risks.

International Comparisons

The 2010 Eurobarometer survey included an extensive series of questions about new and emerging biotechnologies. As in the United States, familiarity with synthetic biology tends to be limited. These data show that public familiarity with new technologies is often associated with opinions about the technology. In the case of nanotechnology, Europeans who are more familiar with the technology are more likely to see nanotechnology as safe and beneficial. In the cases of GM foods and animal cloning, greater familiarity with the technology is not associated with positive assessments of it (Gaskell, et al. 2010).

Animal Research

The medical research community conducts experimental tests on animals for many purposes, including to advance scientific understanding of biological processes and test the effectiveness of drugs and procedures that may eventually be used to improve human health.

Most Americans support at least some kind of animal research. A 52% majority favors the use of animals in scientific research, whereas 43% are opposed, according to a 2009 Pew Research Center survey. Nearly two-thirds said they favor "using animals in medical research" (VCU 2007). Further, 55% of Americans consider "medical testing on animals" to be "morally acceptable," whereas 38% say it is "morally wrong," according to a 2011 Gallup survey (Saad 2011b). A 2008 Gallup survey also found a majority of respondents supported this kind of research; 64% opposed "banning all medical research on laboratory animals" and 59% opposed "banning all product testing on laboratory animals" (Newport 2008).

There is a sizeable gender gap in opinions about animal research. Women are less likely than men to support animal research; 42% of women favor the use of animals in research, compared with 62% of men (Pew Research Center 2009a). Similarly, women are less likely than men to say that medical testing on animals is "morally acceptable" (Saad 2010).

Opposition to using animals in research has grown in the past two decades. When asked whether scientists should be allowed to do "research that causes pain and injury to animals like dogs and chimpanzees if it produces new information about human health problems," between 42% and 45% of Americans disagreed in the early 1990s. This proportion increased to 51% in 2001 and 56% in 2008 (figure 7-18; appendix tables 7-35 and 7-36).[41]

Past NSF surveys suggest that the public is more comfortable with the use of mice in scientific experiments than the use of dogs and chimpanzees (NSB 2002). In 2001, 68% of Americans agreed that "scientists should be allowed to do research that causes pain and injury to animals like mice if it produces new information about human health problems," compared to 44% who expressed agreement when the question focused on dogs and chimpanzees (NSB 2002).

International comparisons on animal research are scarce. Half of Malaysians agree that "although research on animals may cause suffering, it has to be done for the sake of mankind." In Europe, two-thirds agree that "scientists should be allowed to do research on animals like mice if it produces new information about human health problems." A survey conducted by the Gallup Organization in 2003 showed that Americans and Canadians were more likely to tolerate scientific research on animals than the British. When asked, "Regardless of whether or not you think it should be legal, please tell me whether you personally believe that in general medical testing on animals is morally acceptable or morally wrong," the majority of adults in the United States and Canada believed it was morally acceptable (63% and 59%, respectively). In contrast, the majority of British respondents thought it was morally wrong (54%) (Mason Kiefer 2003).

Science, Engineering, and Mathematics Education

In much of the public discourse about how Americans will fare in an increasingly S&T-driven world, quality education in science and mathematics is seen as crucial for both individuals and the nation as a whole.

In the 2008 GSS, the majority of Americans in all demographic groups agreed that the quality of science and mathematics education in American schools was inadequate (appendix tables 7-37 and 7-38). Their level of agreement increased with education, science knowledge, income, and age. Dissatisfaction with the quality of math and science education increased from 63% in 1985 to 70% in 2008, peaking at 75% in 1992 (figure 7-19). Further, about half of Americans said that their local public schools did not put enough emphasis on teaching science and math, an equal portion (48%) said the emphasis was about right, and just 2% said there was too much emphasis on teaching science and math in the local schools (Rose and Gallup 2007).

In addition, the proportion of Americans who said they believe the federal government is spending too little money on improving education in the biennial GSS surveys has remained greater than 70% since the early 1980s. This is consistently one of the top areas where the public feels government spending is too low (figure 7-14; appendix table 7-26).

Notes

[35] This survey was conducted prior to the earthquake and tsunami in Japan on March 11, 2011.
[36] There is some evidence from a large scale experimental study that the wording used in such questions ("global warming" or "climate change") can have an effect on reported beliefs about global climate change (Schuldt, Konrath, and Schwarz 2011). Earlier studies suggested that such wording differences had little effect (EC 2008; Villar and Krosnick 2010).
[37] The two questions from the 2009 Gallup survey were each asked to half of the sample (n = 500).
[38] Countries with nuclear plants include Belgium, Bulgaria, the Czech Republic, Finland, France, Germany, Hungary, Lithuania, the Netherlands, Romania, Slovakia, Slovenia, Spain, Sweden, and the United Kingdom. Two exceptions to this pattern are Romania and Spain, both of which have operational nuclear power plants but where the level of support for nuclear energy is below the EU average. An earlier Eurobarometer study showed that respondents in Spain and Romania were less aware of the fact that their countries have nuclear power plants than respondents in other countries with nuclear plants in operation (EC 2008a). This low level of awareness regarding the operation of a nuclear plant in their country may lead to a less positive attitude about nuclear energy.
[39] According to a report from The National Academies, more than 600 products involving nanotechnology are already on the market; most of them are health and fitness products such as skin care products and cosmetics (The National Academies, 2008b).
[40] This pattern of data is consistent with findings from a meta-analysis of 22 studies conducted in the United States and elsewhere by Satterfield et al. (2009).
[41] The increase in the proportion of respondents who disagree with this statement may be related to methodological issues, because of the changes in data collection. See note 5.
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