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The Association Between Intolerance of Ambiguity and Decline in Medical Students' Attitudes Toward the Underserved

Wayne, Sharon MPH; Dellmore, Deborah MD; Serna, Lisa; Jerabek, Roger MA; Timm, Craig MD; Kalishman, Summers PhD

doi: 10.1097/ACM.0b013e31821dac01
Medical Students' Attitudes

Purpose Little published research details the risk factors for the decline in students' attitudes toward underserved populations during medical school. The authors assessed the association between this attitude change and intolerance of ambiguity (the tendency to perceive novel or complex situations as sources of threat), since treating underserved populations often involves a high level of complexity.

Method The University of New Mexico School of Medicine administered a survey assessing attitudes toward underserved populations at matriculation and at graduation to seven consecutive medical school classes (matriculation years 1999 to 2005). The university also administered a survey measuring tolerance of ambiguity at matriculation. Five hundred twenty-nine students were eligible to complete both surveys between 1999 and 2009.

Results Three hundred thirteen (59%) students completed the attitude survey at matriculation and graduation. Attitude scores for a majority of students (69%) decreased from matriculation to graduation. Changes in scores ranged from +25 to −35; the average change was −4.5. Linear regression analysis showed that those who were tolerant of ambiguity (top 20% of tolerance of ambiguity scores) were significantly less likely to have declines in attitudes toward the underserved; the coefficient was 3.69 (P = .003). Other factors independently associated with maintaining high attitude scores were being female and starting medical school at age 24 or younger.

Conclusions Attention to, and practice with, ambiguous situations may help moderate decreases in attitudes toward underserved populations. Medical education should address the fact that physicians face much ambiguity and should offer students tools to help them respond to ambiguous clinical situations.

Ms. Wayne is associate scientist, Office of Program Evaluation, Education, and Research, University of New Mexico School of Medicine, Albuquerque, New Mexico.

Dr. Dellmore is assistant professor, Department of Psychiatry, University of New Mexico School of Medicine, Albuquerque, New Mexico.

Ms. Serna is program manager, Office of Program Evaluation, Education, and Research, University of New Mexico School of Medicine, Albuquerque, New Mexico.

Mr. Jerabek is associate scientist, Office of Program Evaluation, Education, and Research, University of New Mexico School of Medicine, Albuquerque, New Mexico.

Dr. Timm is professor of internal medicine and associate dean for undergraduate medical education, University of New Mexico School of Medicine, Albuquerque, New Mexico.

Dr. Kalishman is director, Office of Program Evaluation, Education, and Research, University of New Mexico School of Medicine, Albuquerque, New Mexico.

Editor's Note: A commentary on this article appears on page 799.

Please see the end of this article for information about the authors.

Correspondence should be addressed to Ms. Wayne, Office of Program Evaluation, MSC 08 4550, University of New Mexico, Albuquerque, NM 87131-0001; e-mail:

First published online May 25, 2011

An increasingly important goal for many medical schools is addressing the lack of health equity in the United States, a problem predominantly seen in poor and underserved populations. To address the issue of health equity, it is important to produce physicians with favorable attitudes toward populations that experience the negative consequences of an inequitable health care system. Yet, the process of educating medical students to become physicians is often associated with an increase in students' negative attitudes toward the poor and underserved.1–5 A better understanding of the factors associated with the development of these negative attitudes could be helpful in making admissions decisions or in developing curricula aimed at attenuating this attitude change. Although several longitudinal studies have measured the change in attitudes toward the underserved,1–5 an evaluation of risk factors for this change has been generally limited to unadjusted analysis. A longitudinal study evaluating the simultaneous effect of multiple factors influencing attitude change is lacking.

Intolerance of ambiguity is a topic that received a fair amount of attention in the medical literature of the 1980s and 1990s but has received very little attention since then. Norton6 defined intolerance of ambiguity as “the tendency to perceive situations that are novel, complex, or insoluble, as sources of threat.” Budner7 postulated that individuals who are distressed by ambiguous situations would try to avoid them. Several studies in the 1990s found that medical students' tolerance of ambiguity was related to their attitudes toward classes of patients whose problems might be perceived as especially “novel, complex, or insoluble.” Merrill and colleagues8 found that medical students with high intolerance scores were more likely to express a desire to avoid hypochondriac, geriatric, and chronic pain patients than students with lower intolerance scores. Another study found that medical students with higher intolerance of ambiguity had more negative attitudes toward alcoholic patients.9

As a group, the poor and underserved often present with novel and complex medical issues.10,11 They may wait longer to seek care and then present with medically severe and psychosocially complex problems,12,13 their treatment compliance can be complicated by the inability to afford examinations and medications,14,15 and follow-up is often episodic because of circumstances such as lack of transportation.16,17 For these reasons, we postulated that treating the underserved involves more ambiguity than treating populations with more financial resources and greater access to health care, and we were interested in determining whether there was an association between medical students' tolerance of ambiguity and the change in their attitudes toward the poor and underserved.

The purpose of this study was to describe the change in students' attitudes toward the poor and underserved over the course of medical school and then to determine whether attitude change was associated with student characteristics, particularly tolerance of ambiguity. We hypothesized that medical students with greater intolerance of ambiguity would have a greater decrease in their attitudes toward the poor over the course of medical school than students with higher tolerance of ambiguity.

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At matriculation and at graduation, all students at the University of New Mexico School of Medicine (UNMSOM) are asked to complete a survey entitled Medical Students' Attitudes Toward the Underserved (MSATU).18 The MSATU assesses attitudes about medical care and underserved populations; it has good internal consistency (alpha > .80)1 and high agreement among researchers testing its content validity.18 The instrument contains 37 statements covering four areas: societal expectations, professional responsibility, basic services, and expensive procedures, which combine to create a total attitude score. Students rank the statements using a scale of 1 (strongly disagree) to 5 (strongly agree); a higher score indicates a more positive attitude toward the underserved. The scores were standardized to t scores with a mean of 50 and a standard deviation of 10. We began administering the MSATU survey in 1993.

At matriculation, we also ask students to complete Budner's Intolerance of Ambiguity (IA) questionnaire.7 The survey contains 16 items that students rate on a six-point scale, from 1 (strongly disagree) to 6 (strongly agree). Eight items are negatively worded and were reverse-coded prior to scoring. The survey has been shown to have good validity7 and moderate reliability.19 Total scores can range from 16 to 96; higher scores indicate greater intolerance of ambiguity. We began administering the IA questionnaire in 1984.

We also query students at matriculation about the field of medicine in which they intend to practice. There are 26 choices, including unknown, and students are asked to indicate their first and second choices. We considered students selecting any of the following as their first choice to have an early interest in primary care: general internal medicine, general pediatrics, or family medicine. Completion of surveys at UNMSOM is voluntary, and all students sign an informed consent document prior to participating in survey research.

We have a high response rate for surveys administered at matriculation—96% of students completed the MSATU and IA at the beginning of medical school between the years 1993 (the first year we administered the MSATU) and 2005 (the last year for which we have corresponding data at graduation). The response rate at graduation is not as high, especially in the early years. For students beginning school between 1993 and 1998, less than 40% of those who completed the MSATU at matriculation also completed it at graduation. For matriculation years 1999 to 2005, 63% of students completing the MSATU at matriculation also completed the survey at graduation.

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Our study

Because of the low response rate in the early years, we restricted our study sample to matriculation years 1999 to 2005, during which 529 students who had begun medical school at UNMSOM had also graduated.

We calculated attitude change by subtracting MSATU score at matriculation from the score at graduation. For participants with large change scores, we examined the original paper surveys and found no evidence that the data were unusable. We looked at the association of attitude change with the following variables: intolerance of ambiguity, gender, age, ethnicity, early interest in primary care, and baseline MSATU score. Variables that were associated with change in MSATU score in unadjusted analyses using P = .10 were included in a linear regression model to determine their relationship to attitude change, controlling for other variables. We categorized age at the median because of its highly skewed distribution. We initially included ambiguity score in the regression model as a continuous variable, and it was statistically significant (P ≤ .01, data not included). Because it is difficult to interpret a coefficient for a continuous variable, we wanted to categorize ambiguity score to better quantify its association with attitude change. We looked at scatter plots and observed that the association was driven by students with low intolerance scores (or, conversely, those with high tolerance of ambiguity), and we therefore categorized scores as lowest 20% (those most tolerant of ambiguity) and highest 80% (those more intolerant of ambiguity). We used SAS/Stat software (version 9.2, Cary, North Carolina) to analyze our data. The human research review committee at UNMSOM approved this study.

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Of the 529 students who had begun medical school at UNMSOM and had graduated by the spring of 2009, 502 (95%) of them had completed the MSATU and IA at matriculation. Of these, 315 (63%) also completed the MSATU at graduation. We excluded two students for whom we did not have information on ethnicity, so we had data for our study from a sample of 313 (59%) students. Students who completed both MSATU surveys were not statistically different from those completing only the initial survey for the variables gender, age, minority status, intolerance of ambiguity score, or initial MSATU score (data not included).

At matriculation, students had a mean MSATU score of 54.9; four years later this score had dropped by an average of 4.5 points (see Table 1, first row). Figure 1 shows the frequency distribution of the change in MSATU scores from matriculation to graduation; the vertical dotted line indicates zero or no change. Some students' scores increased from matriculation to graduation (87 of 313; 28%), but, for most (215 of 313; 69%), scores decreased during the four years of medical school (11 of 313 [3%] had no change in score). The amount of change in MSATU score varied widely, from an increase of 25 points to a decrease of 35 points. IA scores ranged from 26 to 73, with a mean of 51; the cut point for the lowest 20% of scores, the tolerant group, was 44. Seventeen percent of students with a decrease in MSATU score were in the tolerant group compared with 28% who had either no change or an increase in MSATU score (data not included).

Table 1

Table 1

Figure 1

Figure 1

Table 1 also shows the mean MSATU score at matriculation and its change across four years by variables of interest, including ambiguity score, demographic variables, and whether students had an interest in primary care at matriculation. Students who were more intolerant of ambiguity had significantly greater decreases in attitude score from matriculation to graduation than those who were more tolerant (−5.1 versus −1.8, P = .01). Men had a significantly larger decrease in score than did women (−5.8 versus −3.5, P = .03), and older students had a larger decrease than younger students (−5.5 versus −3.4, P = .05). The differences in attitude change by minority status and interest in primary care at matriculation were not statistically significant. Initial MSATU score and subsequent change in score were significantly and negatively correlated (r = −0.28, P < .01, data not included), suggesting that at least some of the change in MSATU score is due to regression to the mean and indicating the importance of including the initial score in a regression model.

The changes in MSATU score, described in Table 1, are shown graphically in Figure 2. Two patterns are apparent from the graphs: For ambiguity score and age, MSATU scores are similar at matriculation and diverge from that point; for gender and early interest in primary care, MSATU scores differ at matriculation and remain apart.

Figure 2

Figure 2

Table 2 shows the results of regression analysis. All variables from Table 1 that were associated with MSATU change using P = .10 were included in the model. Regression analysis shows that high tolerance of ambiguity has a significant positive association with change in MSATU scores after controlling for gender, age, early interest in primary care, and initial MSATU score. The coefficient for tolerance of ambiguity (3.69) indicates that those with high tolerance have a change in MSATU score that is more than three times greater (more positive) than those with lower tolerance. Female gender and younger age were also significantly associated with more positive change in MSATU score. Early interest in primary care was of borderline significance (P = .05). MSATU score at matriculation had a significant negative association with change in MSATU score.

Table 2

Table 2

We reran the regression model excluding extreme values for change in MSATU score. We first excluded anyone with a change, positive or negative, of 25 points or more (8 participants). The results were very similar to those in Table 2. When we excluded those with a change of 15 points or more (39 participants), only two of the five variables in Table 2 were significantly associated with attitude change: tolerance of ambiguity and MSATU score at matriculation (data not included). We performed one further check on our data. We ran the final model for the 1993–1998 matriculants, whom we had excluded because of low response rates. None of the variables were significantly associated with attitude change in this early group; we suspect that this is due to the low response rate and the fact that, in this group, there were significant differences between responders and nonresponders for many of our variables of interest.

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This study found tolerance of ambiguity to be significantly and independently associated with attitude change: Students who were tolerant of ambiguity were significantly less likely to have a decrease in their attitude toward the poor and underserved compared with students who were less tolerant of ambiguity. Other factors independently associated with a lack of decline in attitudes toward the poor and underserved were being female and starting medical school at age 24 or younger.

Most students arrive at medical school with high idealism and the desire to improve the world.5,20 For the most part, the preclinical years are focused on learning basic sciences in a systematic and organized fashion. Often, not until students begin clinical clerkships do they experience the ambiguity and uncertainty inherent in medicine. Many patients receiving care at teaching hospitals served by medical students are poor and underserved, and students get firsthand exposure to the reality of practicing medicine and applying scientific knowledge to real people with complex problems. Students who begin medical school relatively intolerant of ambiguity might naturally experience declines in their attitudes toward the underserved as they become more educated in what it means to treat the underserved; the negative attitudes of these students may be a response to the anxiety that they experience when treating the poor and underserved.

Our finding that attitudes toward the poor and underserved become more negative over the course of medical school is supported in the literature. Crandall et al,1,2 who developed the instrument used in this study, conducted longitudinal studies of medical students at two different schools and found that students showed increasingly negative attitudes toward the poor and underserved during the four years of medical school. Women had more positive attitudes toward the poor and underserved than men, and the decline in attitudes was not associated with the students' preclinical curriculum (problem-based learning compared with a more traditional approach). Godkin and colleagues,4 using the same instrument, found similar declines in medical students' attitudes that were also unrelated to curriculum (a traditional curriculum compared with one that included experiences with recent immigrant populations). A longitudinal study of medical students in Canada used a different instrument (the Attitudes Toward Social Issues in Medicine questionnaire) but also found declines in scores during medical school.5 In this study, women's scores were higher than men's, but both declined over time. One publication suggests that attitudes may actually increase between the second and fourth years of medical school, but the brevity of the article (one page) makes it difficult to evaluate.21

We are unaware of other studies that have evaluated the association between age and decline in attitudes toward the poor and underserved; our finding that younger students are less likely to report decreased attitude scores may be a novel one. However, our medical school admits students with a wide range of ages, which allows us to evaluate this association; other medical schools may not have enough age diversity to do so.

Recent studies have described declines in other measures over the course of medical school as well. Grbic and Slapar22 report a decrease, from matriculation to graduation, in students' intent to serve the underserved. Other authors have described declines in empathy during medical school.23–25 Although empathy and intent to serve the underserved are different constructs than attitudes toward the underserved, taken together these studies may describe what Newton and colleagues23 refer to as a “hardening of the heart.”

In contrast to attitudes, which seem to decline over time, there is debate whether tolerance of ambiguity is a fixed or modifiable trait.7,9,26–28 However, it is not ambiguity itself but rather the reaction it causes (feeling threatened) that seems at the heart of the issue. Some authors suggest that including more humanities in medical education can help inculcate tolerance of ambiguity in medical students.29 Other research suggests that using a biopsychosocial model in education, as opposed to a strictly biomedical model, may result in students having fewer stressful reactions to uncertainty.30 However, most medical schools now do include more humanities and psychosocial models in their curricula.

We think that these approaches seem too general to address issues related to intolerance of ambiguity. We suggest directly acknowledging the ambiguity inherent in medicine and the anxiety that it can cause. We need to kindly remind our students of their human nature and thus their fallibility. Our students need to learn that healing may be accomplished in the relationship through listening, acknowledgment, and support, and not necessarily in “fixing” or “solving” complex problems. We also suggest helping students work through some specific scenarios, taken from student experience, on how to deal with ambiguous situations with the hope that it may help make these situations less stressful in the future. Anticipatory guidance may enable students to increase their belief in themselves and in their ability to successfully adapt to ambiguous situations.31–33 Merrill and colleagues8 note that “many years ago, medical education was characterized as a series of steps to strengthen the students' ability to tolerate uncertainty.” Our results imply that it may be time to reexamine the concept of ambiguity in medicine.

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Our study's strengths are its sample size and longitudinal nature—We have followed seven classes of medical students from matriculation to graduation and measured attitudes at both time points. However, there are several limitations. First, the use of students from a single school may limit our ability to generalize the results to other schools. Second, although our response rate of 59% is in line with, or better than, other longitudinal studies, we cannot rule out some response bias. Third, Budner's IA questionnaire was not specifically designed for medical students, and it could be argued that it is too general for our purposes. However, at the time we began administering it (1984), a more specific instrument was not available. Since that time, at least one survey of physicians' reactions to uncertainty has been developed.34 Fourth, although we measured tolerance of ambiguity prior to the ascertainment of change in attitude, the association we found is not necessarily causal. And finally, we have not evaluated any interventions aimed at minimizing the threat some students feel when faced with uncertainty, so further study is needed regarding our suggestions.

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Helping students identify and address ambiguous situations in medical education and medical practice may moderate decreases in attitudes toward underserved populations. Although we cannot change the fact that doctors face ambiguity in their work, we may be able to better prepare students to understand and cope with this ambiguity. If we begin by informing students of the stressors in medical education and medical practice, acknowledging the ambiguities in clinical settings, and then providing opportunities for reflection or debriefing on what they experienced, we might reduce the number of instances in which students experience ambiguity as threatening. We might thereby make experiences more manageable and stem some of the declines in attitudes toward the underserved.

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Other disclosures:


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Ethical approval:

This research was approved by the human research review committee at the University of New Mexico School of Medicine.

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Previous presentations:

Early results from this study were presented in poster format at the annual meeting of the American Evaluation Association in Orlando, Florida, on November 11, 2009.

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