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Women in Science: The Project Access Study

By Gerhard Sonnert

January 1999

Harvard physicist Gerhard Sonnert is the author of an influential study (with Gerald Holton) comparing career advancement for women and for men in science, starting with recipients of prestigious postdoctoral fellowships— arguably the best and the brightest. Even in the modern era in which gender discrimination has been formally abolished, women fall systematically behind for what appear to be complex reasons.


Since the early 1970s, huge numbers of women have entered, and succeeded in, science careers — careers that in the preceding decades had been an almost exclusively male domain. Nevertheless, the influx of women has clearly been uneven by discipline and subdiscipline (Babco 1997), and a multitude of gender disparities still exist (Davis et al. 1996, Fox 1995, Zuckerman et al. 1991). It is rather obvious that pervasive gender discrimination kept women from pursuing science careers in the earlier period. Yet it is much less plausible to identify overt gender discrimination as the sole and sufficient cause of the more varied
gender disparities that persist today. More complex explanatory models are needed to capture
an ever more complex reality.

A useful framework for understanding scientific career paths is the“kick-reaction” model (Cole and Singer 1991), according to which a career path in science is formed by a sequence of numerous (positive or
negative) “kicks” from the environment, followed by “reactions” to these kicks by the individual.
1 When applied to today’s science careers of women, the model posits that a multitude of relatively small and subtle disadvantages, both in terms of kicks and reactions, accumulates in women’s career paths and thus makes less likely the full parity in career outcomes for women scientists as a group. This forms a picture consistent with Robert K. Merton’s concept of the “Accumulation of Advantages and Disadvantages” over the course of a science career (Merton 1973, Zuckerman 1989).

The Project Access study

To disentangle the complex causal processes shaping scientific careers, our research project,
called Project Access, controlled the effects of early career experiences by focusing exclusively
on a group of female and male scientists2 who started their careers from the same kind of auspicious
position. All had received a prestigious postdoctoral fellowship. Furthermore, to illuminate
the fine structure of our participants’ career paths, Gerald Holton and I augmented a quantitative
research approach with a qualitative one.

Our data included 699 replies to a structured questionnaire, as well as 200 open-ended, face-to-face interviews. The questionnaire respondents comprised 508 men and 191 women who had received a postdoctoral fellowship from the National Science Foundation (NSF) or the National Research Council (NRC). The years of their fellowship awards ranged from 1952 through 1986. Our sample thus included both women who began their scientific careers before the pivotal epoch of the early 1970s and women who entered theirs afterward. Face-to-face interviews, each lasting about two to three hours, were conducted with
92 men and 108 women who had received postdoctoral fellowships from NSF, NRC, or the
Bunting Institute of Radcliffe College, or who had been Bunting finalists.

Selecting these scientists as our research subjects allowed us to investigate the merits of two antithetic hypotheses about gender differences in careers: “glass ceiling” and “threshold.” The “glass ceiling” hypothesis postulates an invisible but real barrier that impedes women from reaching the top of their profession. Women scientists who have been awarded prestigious postdoctoral fellowships should have accumulated significant advantages up to that point, and should be highly qualified, as well as motivated, to pursue a successful research career in the sciences. If these promising women scientists as a group turn out to be less successful than comparable men in attaining high positions, they may be said to have encountered a glass ceiling of gender-specific obstacles in the later stages of their professional careers.

The alternative hypothesis to the “glass ceiling” notion of career development is that of a “threshold.” According to this model, the processes of professional stratification would be gender-neutral for those women who had succeeded in overcoming certain earlier barriers. These women would be said to have passed a threshold beyond which gender no longer matters in careers. Again, our choice in sample selection provided a research site for detecting such a phenomenon.

Career outcomes of the former postdoctoral fellows

Before summarizing a few key results from Project Access (details in Sonnert and Holton 1995a,b, 1996; Sonnert 1995, 1995/96), I should emphasize that we did not find monolithic blocks of women scientists on the one side and men scientists on the other. Rather, we typically observed great variations within each gender group and a great deal of overlap between the genders. What we report are differences of degree, of statistical trends.

As for academic rank achievement, we found substantial differences by academic field. In biology,
our group of women scientists appeared to have overcome a threshold. There were no statistically
significant differences in their career progress through the academic ranks, compared with that of their male cohorts. However, great gender disparities were found in PSME (physical sciences, mathematics, and engineering), even in this “elite” sample, which thus conformed to the pattern that is well known for the population as a whole (see table, this page). Here a glass ceiling became clearly visible. Controlling for the level of publication productivity, women were still at a rank disadvantage — again with the exception of biology, where the situation was more favorable for women than that in other sciences. (The issue of publication productivity receives special attention below.)

The observed contrast between the disciplines is consistent with the view that rare representatives
of a particular social group, called tokens, tend to face particular difficulties in obtaining career
success in their fields (Kanter 1977). This appears still to be the case in the physical sciences,
mathematics, and engineering, whereas for women biologists, who may have reached a “critical
mass” some time ago, gender stratification within the discipline seems attenuated. One may speculate
that the relatively long and strong tradition of women in biology, as compared with that in
other natural sciences, has contributed to the reduction of the gender gap also in career success
among those engaged in biological research.

In terms of institutional prestige, the women of our questionnaire sample were well represented
at top-rated departments. Twenty-nine percent of the women working in academe, compared with 27% of the men, were located at institutions ranked among the top 15% in a large national survey (Jones et al. 1982). But women, as a group, “paid” for prestigious affiliation with disadvantages in rank achievement, whereas men did not experience such a tradeoff. There was a particular dearth of women full professors at the most prestigious institutions.

The attrition rate (proportion of former fellows who are no longer research scientists) was 10.5% for women and 8.5% for men in our questionnaire sample. This gender difference did not reach statistical significance. As a group, the female former fellows were remarkably persistent in their pursuit of a science career. A considerable gender difference, however, existed in the reasons given by those who had left science. As one might expect, leaving science was more strongly connected with family responsibilities for women than for men.


Various kinds of potential obstacles contribute to differences in career outcomes. Among the “kick”-type of obstacles, we should note that gender discrimination has not vanished. Seventy-three percent of our
women interviewees reported they had experienced some instance(s) of discrimination — whereas 13% of the men said they had been subject to reverse discrimination. There were reports of a few egregious cases, such as the denial of jobs and tenure for women who considered themselves well qualified for a positive decision. But in the interviews there were many more accounts of very subtle exclusions and marginalizations. The latter obstacles might be illustrated by the problems women scientists reported facing in the area of scientific collaboration. When asked for the degree of collaboration with other scientists during different stages of a scientist’s career, women reported being slightly more collaborative than the men
before the postdoctoral fellowship, i.e., during graduate school, whereas they collaborated less
than the men both during and after the postdoctoral stage (see table, this page). Thus, compared
with men, women, as a group, experienced less collaboration as an equal or senior partner,
whereas they experienced more collaboration as a junior partner. It has been proposed that it may be harder for women to establish egalitarian, collegial collaborations (Reskin 1978). Comments in our interviews
supported this suggestion. Several women said that their postdoctoral advisors ignored them, and others noted that their advisors treated them as subordinates.


Even our group of women — “atypical” in that they were, at least initially, highly successful doctoral-level scientists — differed on average from their male cohorts in their own estimation of self-confidence, ambition, and related traits in ways that echo traditional gender patterns of socialization. For instance, substantially more men than women considered their scientific ability to be above average (men: 70%; women: 52%), whereas more women than men considered theirs to be average (men: 18%; women: 34%). When asked whether they should have handled their career obstacles in a different way, many more women than men thought they should have had more confidence or been more assertive (25% vs. 5%). In addition, many more
women than men (16% vs. 4%) in our interview sample said they had had vague or unclear career
aspirations when they started out in science.

Styles of doing science

Handicaps in the area of “kicks” and in the area of “reactions” are likely to interact and reinforce each other. One result of this interaction may be the tendency to develop gender-specific styles of doing science. A considerable group among our interviewees recognized such styles. Somewhat more women than men reported they believed in the existence of gender differences in the work of scientists in general (men: 49%; women: 61%). Moreover, substantially more women interviewees than men thought that their own gender influenced the way they pursued their work. The area in which such a gender influence was most commonly thought to play a role was the professional conduct and interaction among scientists (men: 26%; women: 51%). Fewer interviewees thought that their own gender influenced their choice of research subjects (men: 16%; women: 40%) and their ways of thinking in science (men: 20%; women: 36%). Still fewer interviewees thought there were gender influences on the methods they used in their scientific work (men: 10%; women: 35%).

Women’s professional conduct: Less careerist

Here is a closer look at the different areas of perceived gender differences in scientific style. A common observation among the interviewees, both men and women, was that, in terms of professional conduct, men scientists were found to have more “entrepreneurial spunk,” as a female interviewee called it. They are, in this view, more aggressive, combative, and self-promoting in their pursuit of career success, and so they achieve higher visibility — in short, they are better at playing the “political game” of career advancement. For instance, some women interviewees reported that men have a way of “showing off ” at conferences that alienates women. The following comment by a female scientist illustrates this male behavior:

“... the men showed off for each other, they took themselves terribly seriously and they said any kind of
thing that came to their head. I call it ‘professor talk,’ and I can do it very well.... And I found that a waste of
my time.”

Whereas “professor talk” may indeed be a waste of time in terms of exchanging research information or gaining scientific insights, it may be anything but wasteful in terms of its hidden agenda. Professor talk — or a “bull session” or “chatty self-promotion,” as other women respondents called it — may have the function of a bonding ritual. The social bonds thus forged may then have some beneficial effects on a scientist’s research and career.

Women’s problem choice: The niche approach

With respect to choosing subfields and problems, a number of our male and female respondents agreed with a woman who noticed “fewer women in highly theoretical/ mathematical sub-fields.” But gender differences appeared to go beyond differences in mathematics interest or training. In terms of problem selection, many women reported to be following what could be termed a “niche approach,” creating their own area of research expertise. A good example is a female interviewee who liked “to sense that I had my own area, that I wasn’t just a cog.” Similarly, a woman respondent said that she was predisposed to selecting research problems that were completely her own, because “I very much dislike working on problems that I know other people are working on.” Rather than competing with other researchers and research groups in a race
toward the solution of the same problem, she carves out a niche for herself. Of course, following a niche approach was not exclusively female. And it is not necessarily disadvantageous for career success.

Women’s methodology: Perfectionism

When our interviewees mentioned a specifically female methodologic approach or way of thinking, it hardly ever implied a belief in a“non-androcentric” science that has been occasionally discussed in the literature. Rather, the overriding theme that emerged from both men’s and women’s responses was that women were seen to be more cautious and careful in their methods, and to pay more attention to details, compared with men. A woman respondent believed that “women are often more careful in their research and more hesitant to make statements until they feel they can really ‘prove’ them.” Numerous women acknowledged a tendency to be perfectionists in their scientific work. Another woman scientist stressed women’s attention to detail: “Women are more meticulous … And so I think that does affect how you do science. I don’t know why that is, it just seems that for me, and the other women scientists I’ve dealt with, we tend more to deal in the minute details, fine points.” It does not follow, however, that women scientists exclusively concern themselves with details. On the contrary, next to the theme of women’s greater thoroughness, the interviews also brought out the theme that women see the broader picture and do more comprehensive work. In the words of a woman scientist, “women tend to work longer on individual projects and take on projects that are
broader in scope than do men. Women seem to find it more difficult to break projects into small parts.”

Publication productivity: Quantity and quality

These results suggest a reinterpretation of the often observed publication productivity gap between the genders (e.g., Cole and Zuckerman 1984; Fox 1983; Long 1992) — a gap we also found in our group of scientists. The male questionnaire respondents who now work in academe produced an average of 2.8 publications per annum, compared with the women’s 2.3 publications per annum. The tendencies toward thoroughness and comprehensiveness may combine to reduce women’s quantitative publication output. If
women scientists are more thorough and perfectionist than men, on average, and if they favor more comprehensive and synthetic work, the quantity of their publications per annum will tend to be lower. This can have a deleterious effect on careers whenever the sheer number of publications is taken to indicate excellence of a candidate for a position, for instance.

The lower-quantity-but-higher-quality claim that some women made could be just a self-serving
justification of low productivity. However, some indirect factual evidence for the women scientists’ tendency to publish articles containing more substantial or comprehensive work emerged from a small study in which, among other things, we examined the citations in the scientific literature to biologists’ articles (Sonnert 1995). Among this study’s subsample of 25 former NSF fellows in biology who are now academic scientists, women’s articles received significantly more citations per article, on average, than men’s articles did (24.4 vs.
14.4 citations). This greater citation impact might indicate that the women’s articles tended to contain more noteworthy contents, on the whole. Because the sample of this citation study was rather small, we cannot place a great deal of confidence in this finding; but a gender difference in citations per article in the same direction was also found by Long (1992), in a much larger sample of biochemists. Results like these support current efforts in the reward system to shift from a mostly quantitative toward a more qualitative evaluation of scientists’ publication productivity when important decisions about scientists’ careers are made.

Gender socialization and the scientific environment

The reported gender-specific styles of doing science may have various roots. From the “reaction”
perspective of the kickreaction model, one could point to the observed differences in traits, such as self-confidence, and emphasize that females might be socialized in a way that they prefer their own research
niche, for instance, rather than enter the fray with numerous competitors who all work on the same topic. They may take criticism more personally than men and therefore try harder to produce “perfect” work that is above any possibility of criticism. From a “kick” perspective, however, one could stress that the collegial environment may be particularly hostile to women who deviate from accepted standards. A woman scientist, for instance, reported that “there’s always somebody watching for me to make a mistake.” And another woman concurred that women scientists find themselves often “under the magnifying glass.” In their view, the burden of proof is reversed: while male Ph.D.s are considered competent scientists until proven otherwise, their female counterparts have to demonstrate fully their competence before it is generally

Both types of obstacles surely apply to different women scientists’ careers to different extents.
What seems more important than gauging the relative weight of these explanations is to realize
that they tend to combine in bringing about considerably worse overall career outcomes.

Marriage and parenthood

In addition to science-internal problems, many women scientists face the issue of combining a science career and a family. We investigated with our questionnaire sample whether current marital and/or parental status was related to some basic career outcomes (leaving science, employment area, academic rank, publication productivity). In general, we found that marital and parental statuses were unrelated to these career outcomes, both for men and — more surprising — for women. If these overall analyses failed to show any strong interrelationships between the family and the career spheres for women scientists, does this mean there are
none? We believe that interactions between family and science career do exist, but that they have become too complex and idiosyncratic to be captured by such broad variables as marital or parental status.

Rather than thinking of marriage and parenthood as having a fixed effect on women scientists’ careers, we should see marriage and parenthood as a set of opportunities and problems. Women scientists are faced with the dilemma of “synchronizing” the often conflicting demands of three clocks: their biological clock, their career (e.g., tenure) clock, and their spouses’ career clock. On the other hand, as reported to us, a husband and a family can provide emotional security and financial stability, as well as possibly some scientific support if the spouse is a scientist in the same field. Largely depending on how the problems are resolved and the opportunities are utilized, the effect of marriage and parenthood on women scientists’ careers may be positive or negative. Our respondents could make choices about how to deal with the structural constraints and opportunities. Some choices turned out to be more fortuitous than others.


In sum, the gender problem in science careers has not yet been solved. Even the women in our specially selected group faced gender-specific career-obstacles, as shown by collectively less successful career outcomes than for their male cohorts. The disparities were not uniform across the board; they were concentrated in the top ranks of achievement and in fields outside of biology. As the pattern of gender disparities becomes more complex, their causes become more subtle. It may nowadays be futile to search for “the big remaining obstacle” to women’s career parity in the science. Rather, the accumulation of subtle structural disadvantages (“kicks”) together with attitudinal and behavioral disadvantages (“reactions”) may go far to explain gender disparities where they persist. Policymakers should keep this in mind when trying
to influence the social system of science.

A number of policy suggestions of various scope emerged from our work. I shall mention only one of them in conclusion, one that does not require large funds or high-level policy decisions, yet is crucially important (for a comprehensive presentation of suggestions, see Sonnert 1995-6 and Sonnert and Holton 1995b). Students and beginning scientists need to be more aware of the social factors that determine scientific career outcomes. We must end the widespread naiveté among young scientists. Almost all the people we talked with simply loved what they were doing; clearly they would much rather think about science than strategize about their careers. The view that, if the scientific research works out, career advancement will automatically
follow, was particularly prevalent among our female respondents. At a minimum, universities should offer real-world career counseling, perhaps including courses that provide some eyeopening advice on how careers work.



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The author gratefully acknowledges that this research was funded by grants from the Office of Naval Research, the National Science Foundation, and the Ford Foundation. The support by these agencies does not imply their endorsement of the contents of this paper.

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