More Options

Understanding What the American Public Really Thinks About Stem Cell and Cloning Research

Science and the Media

Matt Nisbet

May 2, 2004

Few science and technology-related issues have sparked as much survey attention in the U.S. as the controversy over stem cell and therapeutic cloning research. Interest groups, advocates, and policymakers on both sides of the debate have taken advantage of poll results to support their claims that the public backs their preferred policy outcomes, and the competing camps have staged ongoing public communication campaigns in an effort to shape public opinion. Journalists have also highlighted the results of these surveys, using poll figures to complement their coverage of “who is ahead and who is behind” in the competition to decide stem cell and cloning-related policy.

Given the competing claims about public opinion, I wanted to get a reliable, quantitative sense of trends in public attention, awareness, knowledge, and evaluations of the issue. I located U.S. survey data using the public opinion online search engine ("Polls and Surveys”) of Lexis-Nexis and the Kaiser Health Poll Archive, both provided by the Roper Center for Public Opinion. Keywords such as “stem cell,” “cloning,” or “clone” were used in the search. Additional polls were retrieved from the data archives of, through a Web search, or by contacting various advocacy organizations.

Assimilating the nearly 200 survey questions specific to stem cell research and human cloning proved to be a difficult task. Consequently, this Web column is written with the goal of conveying a great deal of complex information in a highly accessible, yet still rigorous form. Readers are invited to follow up on the details of the data-including field dates, survey sponsor, frequency tabulations, question wording, sample size, and margin of error-in an article recently published in Public Opinion Quarterly (Nisbet, 2004).

Public Attention to Stem Cell Research and Cloning

Given that significant media attention to the stem cell issue did not occur until the summer of 2001, it is not surprising that when surveyed in the fall of 2000, only 20% of Americans reported following the issue either “very closely” or “fairly closely.” Even in early July 2001, only a month before Bush’s nationally televised address, the proportion of Americans following the issue had only increased to 38%. By early August, however, this number had risen to slightly more than a majority of respondents, and polls indicate that in the days after Bush’s announcement, between 40% and 60% of respondents reported that they were following the issue at least somewhat closely. Public attention to the issue remained steady even several weeks after the terrorist attacks of September 11.

In an alternative measure of public awareness, 25% of Americans reported that they had either seen, read, or heard “a lot” about the issue in the weeks immediately following the Bush decision. A few months later, in February of 2002, this figure remained relatively stable at 27%, though a precise trend is difficult to observe because of slightly different question wording.

However, in September 2002, a little more than a year after Bush’s decision, only 13% of respondents reported having seen, read, or heard “a lot” about the issue, whereas 46% of respondents reported “not much” or “nothing at all,” suggesting that overall public attention to the issue had declined from 2001 levels, with this drop in public attention paralleling a drop in media attention.

In terms of issue importance, in the summer of 2001, during the peak of the debate, more than 60% of respondents reported that the issue was either “very important” or “somewhat important” to them. Indeed, roughly a third of Americans reported that they had tuned in for Bush’s August 9 televised address. Bush’s televised speech and the sizable audience should not be overlooked in terms of its potential significance for public understanding of the issue. At least one historian viewed Bush’s speech as remarkable for a presidential address since Bush spent an unusual amount of time outlining the background of the issue, and the competing points of view that fueled the controversy.

Relative to indicators of public attention to the issue of cloning, the available survey data is fairly non-specific to therapeutic cloning applications; instead survey items tracked public attention to reproductive cloning starting with the 1997 announcement of the cloned sheep named Dolly. Through the end of 1998, roughly half of respondents reported following developments related to cloning or having an interest in the issue, with the exception of the announcement of cloned pigs by scientists in Hawaii. In addition, despite the sensationalism surrounding the human cloning claims announced by the Raelians during Christmas week of 2002, less than half of respondents reported that they were following the issue either “very closely,” or “fairly closely".

Public Knowledge of Research and Policy

In the early stages of the controversy, given the low levels of media attention to the issue, the public should not be faulted for a lack of knowledge relative to the specifics of the emerging policy debate. For example, when asked in the fall of 2000, only 17% of respondents reported that they knew that the National Institutes of Health (NIH) had recently announced that the agency would begin accepting applications for federal funding of embryonic stem cell research, and more than two-thirds of respondents either reported “don’t know” or refused the question. (George W. Bush later put on hold the NIH decision shortly after taking office in early 2001).

Yet, by August 2001, despite considerable media coverage, and despite an increase in self-reported attention to the issue, the public still scored relatively low in terms of knowledge. For example, although in one August 10-12 poll, 60% of respondents reported having a “good understanding” of the issue, a few weeks later, only 28% of respondents could correctly identify the criteria under which Bush’s decision would allow a stem cell line to be eligible for funding. A majority of respondents, however, were at least familiar with the crux of the debate, naming the destruction of human embryos as the major reason for the controversy. However, a year later, in September, 2002, when asked in an open-ended question to answer what kinds of stem cells came to mind when thinking about stem cell therapy, more than half answered “don’t know,” and only 17% answered embryonic stem cells.

Specific to public knowledge of cloning, the available survey items are somewhat limited. As early as 1986, 69% of the public indicated that they understood the meaning of the term “cloning.” The recent debate whether to ban all forms of cloning, or to just allow cloning for medical research purposes appears to have complicated matters for the public. In 2002, for example, only a little more than 40% of respondents reported they were either “very clear” or “somewhat clear” on the differences between “reproductive” and “therapeutic” cloning procedures. In terms of knowledge of cloning policy, as of October 2002, more than half of respondents incorrectly assumed that the government already regulated the cloning of humans.

Moral Evaluations of Stem Cell Research

As previously mentioned, much of the opposition to embryonic stem cell research from religious and conservative elites derives from the necessary destruction of human embryos. At the base of this elite opposition is the belief that a human embryo is equivalent to a human life, and that embryos are deserving of the same protections as other human beings. To destroy embryos would therefore be morally wrong, essentially equivalent to murder. Where does the public weigh in on this matter? Previous surveys that have asked Americans about when life begins indicate that a slight majority of respondents have consistently indicated that life begins at “conception.”

Important to note is a 2003 Newsweek poll. This is the lone poll to more carefully explore the public’s definition of “conception,” distinguishing in response categories between a fertilized egg and an embryo. Given this additional precision in measurement, the important implication for embryonic stem cell research is that a combined 58% of the public appears to believe that life begins either at the earliest stage of a fertilized egg or as an embryo.

Given this outlook on when life begins, it would not be surprising to find that embryonic stem cell research might be morally problematic for many respondents. In July of 2001, 54% of respondents agreed that embryonic stem cell research was morally wrong. A month later, this finding remained virtually unchanged, but by May 2002, and later in May 2003, the percentage regarding embryonic stem cell research as morally wrong had dropped in polls to 39%, suggesting that the debate over research had possibly softened initial moral opposition. Clear confidence in this trend, however, is somewhat in doubt given changes in question wording and response categories across the polls.

Trends in Public Support for Stem Cell Research

There is also evidence that the type of embryo used in research matters to respondents. From June 2001 to just after the Bush decision in August 2001, polls indicate that a strong majority of Americans supported research using “extra” embryos left over from in vitro fertilization, and this support appears to have increased slightly from June to just after the Bush decision. Second, when the source of the embryos is left unspecified, it is apparent that public support drops slightly. For example, in a fall 2001 Virginia Commonwealth University survey, only 48% of respondents indicated that they either “strongly favored,” or “somewhat favored” embryonic stem cell research when the source of the embryo was left unspecified. Importantly, when the same exact question was asked a year later in September of 2002, there appears to have been a drop in public support over the twelve month period, with only 35% of respondents indicating that they favored research. Yet as of September 2003, when the same question of respondents was asked again, support appears to have climbed back to approximately the level in 2001. (The confidence interval for each of these three surveys was +/- 3 percentage points.)

Public Support Varies by Type of Embryo Used in Research

In a May 2001 poll that asked about unspecified embryos, 48% of respondents indicated that research should be allowed. Alternatively, Gallup and Harris polls from 2001 — conducted within days of each other — showed strikingly different results. In the Gallup poll, only 38% of respondents indicated that research should be allowed using embryos created specifically for research purposes. A July 2001 Harris Interactive poll that asked specifically about extra embryos left over from fertilization found support to be much higher at 61%. In all, the polls suggests that public support for research appears to depend on the type of embryo used, with generalized public support greatest for “discarded” or “extra embryos.”

Strong Question Wording Impacts Respondent Opinion

The importance of how prospective research is framed is illustrated by two polls taken in early 2001, one sponsored by the Juvenile Diabetes Research Foundation (JDRF) and the second by the National Council of Catholic Bishops (NCCB). Both poll items present strong examples of just how sensitive respondents may be to question wording effects, especially at a time when public attention to the issue was relatively low.

The first poll sponsored by the JDRF includes the following question wording:

“As you may already know, a stem cell is the basic cell in the body from which all other cells arise. Medical researchers have been able to isolate stem cells from excess human embryos developed through in vitro fertilization and fetal tissue that has been donated to research. The medical researchers believe that human stem cells can be developed as replacement cells to cure diseases such as diabetes, Parkinson’s, Alzheimer’s, cancer, heart disease, arthritis, burns, or spinal cord problems. Do you favor the funding of stem cell research by the National Institutes of Health?” (emphasis added.)

Not surprisingly, if the public in the context of a survey question is asked about using less controversial extra embryos for research that might lead to cures for a long list of diseases, public support for funding can be measured at a remarkably high 65%.

In the NCCB poll, research was framed very differently, with strong connotations of abortion and the use of tax dollars:

“Congress is considering whether to provide funding for experiments using stem cells from human embryos. The live embryos would be destroyed in their first week of development to obtain these cells.” The respondents are then asked: “Do you support or favor using your federal tax dollars for such experiments?” (emphasis added).

Given this information, an equally remarkable 70% of respondents voiced their opposition to funding.

When It Comes to Funding, the Source of the Stem Cells Matter

Across non-advocacy polls taken in 2001 that used more neutral question wording, public support appears highest for funding of stem cell research that uses either adult cells (68%), or extra embryos (greater than 50% support across all polls). Public support for funding is lowest, by far, for stem cell research that uses cloned embryos as sources (28%). Important to note is a July 2001 Gallup poll, where respondents were prompted with the response categories “Do you think the federal government should or should not fund this type of research, or don’t you know enough to say?,” more than half of the respondents chose the “don’t know enough to say” response, suggesting a public relatively unaware of the topic. Considering possible shifts in support for funding between 2001 and 2002, the limited number of available measures makes a determination somewhat difficult. The lone 2002 poll asking about support for funding is non-specific to the embryo source, and lacks any background information in the question. Support in this poll registers at 43%, but includes a strong 18% “don’t know.”

Public Support for President Bush’s Televised Decision

The surveys taken in the days and weeks after Bush’s August 9, 2001 nationally televised announcement indicate that the President’s decision appears to have been received favorably by a majority of Americans, as the polls were fairly consistent in showing between 50% and 60% support. Beginning with the first overnight poll on August 9, the trend over the next two weeks indicates that public approval of the President’s decision actually increased slightly. Similar to a Presidential debate, audiences likely relied on post-decision news coverage and punditry to interpret for them whether Bush’s decision was “good” or “bad.” In this case, it appears the White House succeeded in selling the decision to the public. The Bush team’s success is somewhat surprising given that in the days following the President’s announcement, many scientists, pro-research advocates, and newspaper editorial boards strongly questioned the suitability of the existing stem cell lines outlined by Bush.

Public Support for Reproductive and Therapeutic Cloning

Highly relevant to the issue of federal funding for embryonic stem cell research has been the debate over the regulation of cloning. Procedures involving therapeutic cloning are closely linked to stem cell research, since one of their central applications involves the creation of cloned embryos for use in the extraction of stem cells.

At one level, public opinion is fairly clear when it comes to support for reproductive cloning. (Here, in order to categorize the poll questions, a strict definition of the term is adopted from the 2002 report of the President’s Council on Bioethics, with reproductive cloning, or “cloning-to-produce-children” including all cloning technology designed to ultimately result in the birth of a child, no matter the stated reason or justification for such a procedure.) In polls taken between 1993 and 2002, roughly 75% or more of respondents have consistently indicated — across a wide variety of stated purposes — that they disapprove of reproductive cloning. The few exceptions include screening for abnormalities in embryos (52% disapproved in 1993), cloning of embryos for infertility treatment (63% disapproved in 1998), and cloning to produce copies of humans for organs to save others (68% disapproved in 2001). Still, in all of these examples, a majority of Americans disapprove of the procedure.

Since just after the Dolly announcement of early 1997, more than 80% of Americans have consistently answered that reproductive cloning should not be allowed or should be illegal. Still, when the public was asked if they would favor or oppose either an “outright ban on the cloning of human beings,” or “a law that would prohibit the cloning of human beings,” subtle differences appeared. In this case, starting in early 1998 and into the spring of 2002, only a slight majority of Americans favor either an outright ban or a law that would prohibit cloning, suggesting that the public may be somewhat hesitant about backing legislation that completely closes the door on any and all cloning-related research. In fact, when Gallup asked in March 2003 “would you favor or oppose a law that would prohibit the cloning of human beings, or are you unsure?,” (emphasis added), a quarter of respondents answered that they were not entirely certain about the matter.

In contrast, however, a slight majority of Americans approve of cloning that is not designed specifically to result in the birth of a human, but is designed to aid in medical research into the treatment of diseases, or for the purposes of cloning organs and adult cells. This slight majority support remains steady between late 2001 through to September 2002. The public, however, appears to assert reservations when asked specifically about the cloning of embryos for medical research, with majorities voicing their disapproval in May and September, 2002.

Additionally, when asked specifically in early 2003 about legislation that would allow cloning for “laboratory research", but would ban reproductive cloning, only a little more than a third of respondents indicated support for only a partial ban, whereas 40-60 percent of respondents indicated their support for a total ban.


The controversy over human embryonic stem cell research and therapeutic cloning remains unresolved, and the issue may mark a new era of divisive and deadlocked “biopolitics.” What the review of the polls makes clear is that public attention was captured by this emerging conflict during the summer of 2001, but has waned since, as media coverage has subsided, and many other competing issues have come to dominate the political and media agenda. Despite Americans’ elevated attention to the issue in 2001, however, it appears that the public remains in the dark about the science and the policy driving the controversy.

The public possesses strong reservations about research that destroys embryos, preferring if the research must move forward, that scientists make use of either extra embryos left over from in vitro clinics, or adult cells. Additionally, evidence indicates that question wording in surveys can have strong effects on the public’s stated response to these volatile issues.

On the matter of cloning, the public is strongly opposed to reproductive cloning, but resolve softens when it comes to medical applications, while a substantial proportion of Americans remain unsure about the matter. Still, only about a third of Americans support compromise legislation that would allow therapeutic cloning to remain legal.

In all, the analysis points to an important role for the media in shaping future public judgments of stem cell research and human cloning. Evidence of strong question wording effects, combined with the findings relative to low levels of public knowledge, suggest that the public may be highly susceptible to influence by changes in media attention and media characterization of the issue.


Matt Nisbet

Matthew C. Nisbet, Ph.D, is a professor in the School of Communication at American University. From 1997 to 1999, he worked as public relations director for CSICOP and Skeptical Inquirer.