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Attitudes of women in their forties toward the 2009 USPSTF mammogram guidelines: a randomized trial on the effects of media exposure

Published:April 15, 2011DOI:https://doi.org/10.1016/j.ajog.2011.04.005

      Objective

      The objective of the study was to assess women's attitudes toward 2009 US Preventive Services Task Force mammography screening guideline changes and evaluate the role of media in shaping opinions.

      Study Design

      Two hundred forty-nine women, aged 39-49 years, presenting for annual examinations randomized to read 1 of 2 articles, and survey completion comprised the design of the study.

      Results

      Eighty-eight percent overestimated the lifetime breast cancer (BrCa) risk. Eighty-nine percent want yearly mammograms in their 40s. Eighty-six percent felt the changes were unsafe, and even if the changes were doctor recommended, 84% would not delay screening until age 50 years. Those with a friend/relative with BrCa were more likely to want annual mammography in their forties (92% vs 77%, P = .001), and feel changes unsafe (91% vs 69%, P ≤ .0001). Participants with previous false-positive mammograms were less likely to accept doctor-recommended screening delay until age 50 years (8% vs 21%, P = .01).

      Conclusion

      Women overestimate BrCa risk. Skepticism of new mammogram guidelines exists, and is increased by exposure to negative media. Those with prior false-positive mammograms are less likely to accept changes.

      Key words

      Breast cancer is the second leading cause of cancer death among women in the United States.
      • Altekruse S.F.
      • Kosary C.L.
      • Krapcho M.
      • et al.
      SEER cancer statistics review, 1975-2007.
      The breast cancer awareness movement in the United States has brought this issue to the forefront of the contemporary women's health agenda. As a result, routine mammography has increased significantly since 1989 when the first US Preventive Services Task Force (USPSTF) recommendations were published.
      Centers for Disease Control and Prevention
      Screening for breast cancer Guide to clinical preventive services: an assessment of 169 interventions [CDC Report].
      In 2005, 67% of American women over the age of 40 years reported having a screening mammogram in the past 2 years.
      • Cokkinides V.
      • Bandi P.
      • Siegel R.
      • Ward E.M.
      • Thun M.J.
      Cancer prevention and early detection facts and figures 2008.
      For Editors' Commentary, see Table of Contents
      The USPSTF published its updated mammogram screening guideline recommendations in November 2009.
      Screening for breast cancer: US Preventive Services Task Force recommendation statement.
      Notable among the changes was to initiate routine mammography screening at age 50 years, rather than the previously recommended age of 40 years. Despite extensive international study of mammography screening over the last 50 years, the issue of when to start routine screening remains one of the most contentious in the current debate regarding evidence based medical practice. Although there is convincing evidence that screening mammography reduces breast cancer mortality, the greatest absolute reduction is for women between the ages of 50 and 74 years.
      • Moss S.M.
      • Cuckle H.
      • Evans A.
      • Johns L.
      • Waller M.
      • Bobrow L.
      Effect of mammographic screening from age 40 years on breast cancer mortality at 10 years' follow-up: a randomised controlled trial.
      • Nelson H.D.
      • Tyne K.
      • Naik A.
      • Bougatsos C.
      • Chan B.K.
      • Humphrey L.
      Screening for breast cancer: an update for the US Preventive Services Task Force.
      In formulating its new recommendations, the USPSTF guidelines reflect recent data suggesting that 1904 women would need to be screened to prevent 1 breast cancer death of a woman in her fifth decade.
      • Nelson H.D.
      • Tyne K.
      • Naik A.
      • Bougatsos C.
      • Chan B.K.
      • Humphrey L.
      Screening for breast cancer: an update for the US Preventive Services Task Force.
      In fact, the USPSTF concluded that the harm associated with routine screening among women in this age group may outweigh the benefit. Harms included psychological stress associated with false-positive results, unnecessary imaging and associated radiation exposure, biopsies in women without cancer, and morbidity associated with diagnosis of nonclinically significant cancer treatment.
      • Nelson H.D.
      • Tyne K.
      • Naik A.
      • Bougatsos C.
      • Chan B.K.
      • Humphrey L.
      Screening for breast cancer: an update for the US Preventive Services Task Force.
      The USPSTF guidelines were published at a time when national attention was turned toward health care reform. Intense debate within the popular media erupted immediately in the wake of the guideline release.
      • Woolf S.H.
      The 2009 breast cancer screening recommendations of the US Preventive Services Task Force.
      A literature search of popular media articles in major publications indexed in LexisNexis (LexisNexis, Miamisburg, OH) in the 10 weeks following the guideline release yielded 1344 results.

      Lexis Nexis Academic. 2010.

      Although many leaders within the breast cancer awareness movement endorsed the guideline changes, accusations that the new proposals were antiwoman, and potentially politically motivated, soared.
      • Wilensky G.R.
      The mammography guidelines and evidence-based medicine.
      The guideline changes sent a confusing and potentially frustrating message to American women.
      To date, little has been published on the public's attitudes toward these guideline changes. Furthermore, it is unclear what influence the media controversy has had in shaping public opinion. In this study, we aimed to assess women's attitudes toward the screening changes and to evaluate the role of the popular media in shaping these opinions. Are women's attitudes influenced by the popular media? What personal factors may affect their attitudes? Overall, how are the new recommendations being received?

      Materials and Methods

      This study was performed as a randomized trial using a convenience sample to assess attitudes about the new USPSTF breast cancer guidelines and assess whether these attitudes were influenced by exposure to opinion pieces that appeared in the popular media.
      Subjects consisted of English-speaking women between the ages of 39 and 49 years presenting to their primary obstetrician-gynecologist for annual well-woman examinations. All patients meeting the above criteria were invited to participate in the study at the time of registration by the receptionist in 1 of 4 private practice obstetrician-gynecologist offices.
      The study period ran over 3 months in the spring of 2010. After verbal consent was obtained, patients were given an anonymous questionnaire addressing their personal experience with mammography as well as listing their age, breast cancer history, family/friends with breast cancer (up to second-degree relatives), and education level. After this demographic information was obtained, participants were instructed to read a media article on the new guidelines. Participants were given 1 of 2 newspaper articles to read (a 1:1 ratio was obtained).
      Subjects in the first group were asked to read “A backlash of mistrust,” an article written by columnist Ellen Goodman, which was published in the Washington Post shortly after the release of the guidelines.

      Goodman E. A backlash of mistrust. Washington Post (Nov. 25, 2009).

      In this piece, Goodman argues in favor of the guideline changes. She suggests these changes are sound and expresses confidence in the evidence-based conclusions on which the guidelines were based. Goodman criticized the way in which the changes were announced to the public, arguing that the media, rather than the USPSTF, was to blame for the public outcry.
      Subjects in the second group were asked to read “Taking a hit on health care? Why, that's woman's work,” an article written by Joan Vennochi, published in the Boston Globe,

      Vennochi J. Taking a hit on health care? Why that's women's work. Boston Globe (Nov. 19, 2009, Section A17).

      which was highly critical of the new guidelines. She suggested the guidelines were politically motivated and potentially dangerous for women.
      After reading the assigned article, subjects completed additional questions related to their attitudes toward mammography and personal plans regarding mammogram screening. The answers were provided prior to completing the doctor's appointment, generally within 15 minutes of reading the article. Answers were compared across study groups. After completing the survey, all subjects were provided a fact sheet about mammogram screening that was written by the investigators. This fact sheet explained data behind the guideline changes as well as a brief explanation of the makeup and mission of the USPSTF. Respondents with a personal history of breast cancer were excluded.
      Continuous variables were summarized by mean and SD, and Student t tests were used for comparisons between groups. Categorical variables were summarized using frequency measures, and χ2 tests were used as appropriate.
      Our primary analysis was to detect whether participants had different responses on the new breast cancer screening guidelines after they were randomly given 1 of the 2 related articles. Our secondary analysis was to detect whether other factors may also affect their responses. Comparisons on demographical information were made between 2 groups to assure they have similar demographics. P values for all hypothesis tests were 2 sided and statistical significance was set at P < .05. All statistical analysis was performed using SAS (version 9.2; SAS Institute Inc, Cary, NC) statistical analysis software.
      The study was approved by the University of Massachusetts Medical School Institutional Review Board.

      Results

      Approximately 432 patients were invited to participate. An estimated 119 declined participation. The most common explanation given for refusal was time constraints. Of the 313 who agreed to participate, 59 were excluded based on not meeting age criteria, and 5 were excluded because of incomplete surveys. Of 249 completed surveys, 5 were excluded because of respondents with personal breast cancer history. The resulting analytic sample was thus 244 women (Figure 1).
      Figure thumbnail gr1
      FIGURE 1Consort flow sheet
      Davidson. Women's attitudes toward the 2009 USPSTF mammogram guidelines. Am J Obstet Gynecol 2011.
      The study population was predominantly white, college educated with a history of prior mammogram screening (complete demographics, Table 1). The average number of previous mammograms reported was 5.4 (SD 5.07). Sixty-four percent (n = 155) reported no prior workup resulting from an abnormal mammogram finding (defined as 1 or more added imagings or a biopsy). Seventy-six percent (n = 185) had either a family member or a close friend with breast cancer. There was no statistically significant difference between the 2 study groups in any of these factors (results not shown).
      TABLE 1Baseline characteristics of participants
      CharacteristicFavorable articleUnfavorable articleP valueTotal
      Answers, nMean (SD)Answers, nMean (SD)Mean (SD)
      Age, y (n = 243)11944.4 (3.19)12444.2 (3.06).6944.3 (3.12)
      Prior mammogram, n (n = 240)1185.6 (5.08)1225.3 (5.07).585.4 (5.07)
      Prior workup for abnormal mammogram, n (n = 242)1190.85 (1.75)1230.78 (1.60).720.82 (1.67)
      Race (n = 242)119123.66
       White, n (%)108 (91)113 (92)221 (91)
       Black, n (%)4 (3)5 (4)9 (3.7)
       Asian, n (%)5 (4)4 (3)9 (3.7)
       American Indian, n (%)1 (0.8)0 (0)1 (0.4)
       Hawaii/Pacific Islander, n (%)1 (0.8)0 (0)1 (0.4)
       Other, n (%)0 (0)1 (0.8)1 (0.4)
      Education (n = 241)120121.11
       Did not finish high school, n (%)4 (3)3 (2)7 (2.9)
       High school, n (%)20 (17)27 (22)46 (19.1)
       2 year college, n (%)40 (33)23 (19)62 (25.7)
       4 year college, n (%)39 (33)43 (36)81 (33.6)
       Masters/graduate school, n (%)17 (14)25 (21)42 (17.4)
      Family history of breast cancer (n = 242), n (%)*11855 (47)12461 (49).68116 (47.9)
      Friend with breast cancer (n = 242), n (%)11868 (58)12484 (68).10152 (62.8)
      Davidson. Women's attitudes toward the 2009 USPSTF mammogram guidelines. Am J Obstet Gynecol 2011.
      Sixty-two percent of women felt their risk for getting breast cancer was average (19% felt their risk was below average and the same percentage felt their risk was above average). In response to the question, “Approximately what percentage of the women in the United States do you think will get breast cancer in their lifetime?” the average response was 37% (range, 1–90%, Figure 2). Eighty-eight percent of participants estimated the average woman's lifetime risk of getting breast cancer as being greater than 12% (which is the average for a woman in her 40s).
      Figure thumbnail gr2
      FIGURE 2Estimated lifetime risk of breast cancer
      Fully 43% of respondants estimated lifetime risk of breast cancer at 36% or greater, whereas only 11% felt that the risk was 12% or less (the average lifetime risk for this age group is approximately 12%). The average response was 37%, and 78% of respondents felt that the risk exceeded 12%.
      Davidson. Women's attitudes toward the 2009 USPSTF mammogram guidelines. Am J Obstet Gynecol 2011.
      Eighty-nine percent (n = 215) of participants felt that they should have yearly mammograms in their 40s. Among participants randomized to the favorable article, 85% (n = 100) felt this was the case. Among those randomized to the unfavorable article, the percentage was 93% (n = 115) (P = .05). Eighty-six percent (n = 203) felt the guideline changes were unsafe, and 84% (n = 201) would not be comfortable delaying screening mammography, even if their doctor recommended it. These answers did not differ significantly by article group (Figure 3).
      Figure thumbnail gr3
      FIGURE 3Attitudes toward mammography screening guideline changes by article
      Davidson. Women's attitudes toward the 2009 USPSTF mammogram guidelines. Am J Obstet Gynecol 2011.
      Secondary analysis showed that 92% percent (n = 171) with a close friend or family member with breast cancer vs 77% (n = 44) of those without a close friend or family member with breast cancer felt women should continue to undergo routine mammography in their 40s despite the new guideline changes (P = .001).
      Among those with a close friend or family member with breast cancer, 91% (n = 165) felt the new guidelines were unsafe. This differed from those participants who did not have a friend or family member with breast cancer, among whom 69% (n = 38) felt the guidelines were unsafe (P ≤ .0001). There was not a statistically significant difference between those with and those without a friend or family member with breast cancer in terms of willingness to delay mammogram screening if their doctor felt it appropriate (14% vs 23%) (Table 2).
      TABLE 2Perceptions of screening mammography guideline changes after exposure to media article
      VariableDo you feel you should have yearly mammography in your 40s?Do you feel these guidelines are safe?Would you feel comfortable delaying mammograms until age 50 y if your doctor felt this was reasonable in your case?
      Yes, n (%)No, n (%)P valueYes, n (%)No, n (%)P valueYes, n (%)No, n (%)P value
      High school graduate or less48 (89)6 (11).968 (14)46 (85).786 (11)47 (89).28
      ≥2 y of college164 (89)21 (11)24 (13)156 (87)32 (17)151 (83)
      Friend/family with breast cancer171 (92)14 (8).00116 (9)165 (91)< .000125 (14)158 (86).09
      No friend/family with breast cancer44 (77)13 (23)17 (31)38 (69)13 (23)43 (77)
      Prior further workup79 (92)7 (8).2510 (12)73 (88).597 (8)79 (92).01
      No prior workup134 (87)20 (13)22 (15)129 (85)31 (21)120 (79)
      Davidson. Women's attitudes toward the 2009 USPSTF mammogram guidelines. Am J Obstet Gynecol 2011.
      Of the 14% (n = 33) of patients who felt the new guidelines were safe, 48% (n = 16) would still not want to delay mammography until age 50 years if their doctor felt this was reasonable. Patients who had a previous false-positive mammogram were less likely than those who had not had a previous false-positive mammogram to consider delaying until age 50 years, even if their doctors recommended it (8% vs 21%) (P = .01) (Figure 4).
      Figure thumbnail gr4
      FIGURE 4Attitudes of women with prior false-positive mammogram
      Women with a prior false-positive mammogram are less likely than those without to feel comfortable delaying mammography until age 50 years.
      Davidson. Women's attitudes toward the 2009 USPSTF mammogram guidelines. Am J Obstet Gynecol 2011.

      Comment

      Most women in our study overestimated their risk of getting breast cancer (with the average lifetime risk estimated at 37% and the average for this age group being 12%). This is consistent with other studies suggesting American women tend to overestimate their breast cancer risk.
      • Apicella C.
      • Peacock S.J.
      • Andrews L.
      • Tucker K.
      • Daly M.B.
      • Hopper J.L.
      Measuring, and identifying predictors of women's perceptions of three types of breast cancer risk: population risk, absolute risk and comparative risk.
      Eighty-six percent did not feel that the new mammogram guidelines were safe and 84% did not intend to follow them, even if their doctor recommended that they do so. Furthermore, even among those who said that they thought that the new guidelines were safe, nearly half still did not intend to delay onset of regular mammograms.
      A surprising 76% of patients had either a friend or family member (up to a second-degree relative) with breast cancer. This personalizes the issue of breast cancer for women in this age group, moving it from an abstract condition to one that has personal meaning. Among this group 92% felt that they should continue to undergo yearly mammograms. This finding supports a body of research suggesting that the public interprets health policy in relation to their own personal experience and does not have a sophisticated understanding of evidence-based medicine.
      • Carman K.L.
      • Maurer M.
      • Yegian J.M.
      • et al.
      Evidence that consumers are skeptical about evidence-based health care.
      A statistically significant difference was observed between those who had and those who had not experienced a false-positive mammogram in terms of their discomfort complying with the new guidelines (92% vs 79%). This finding suggests that these patients were more likely to view the additional imaging and biopsies as a near miss rather than false alarm.
      This is an important finding because it is in direct contrast to the conclusions drawn by the USPSTF, which cited psychological harm from false-positive results as 1 of the major risks of screening mammography in the fifth decade. Our findings are consistent with other research showing that women are very tolerant of false alarms if they perceive the issue being addressed as significant.
      • Apicella C.
      • Peacock S.J.
      • Andrews L.
      • Tucker K.
      • Daly M.B.
      • Hopper J.L.
      Measuring, and identifying predictors of women's perceptions of three types of breast cancer risk: population risk, absolute risk and comparative risk.
      • Carman K.L.
      • Maurer M.
      • Yegian J.M.
      • et al.
      Evidence that consumers are skeptical about evidence-based health care.
      Although our study did not assess women's perceptions of harm associated with mammography, previous studies show that women do not generally perceive mammography as potentially harmful.
      • Silverman E.
      • Woloshin S.
      • Schwartz L.M.
      • Byram S.J.
      • Welch H.G.
      • Fischhoff B.
      Women's views on breast cancer risk and screening mammography: a qualitative interview study.
      Missing from the public discourse of harm from false alarms is data documenting the morbidity and mortality of breast cancer treatment resulting from overdiagnosis, which is currently perceived only as life saving.
      With regard to the question, “Do you feel you should have yearly mammography in your 40s?” there was a statistically significant difference between the 2 newspaper articles in the expected direction, thus potentially revealing the influence of the popular press on women's thoughts and feelings regarding this issue. However, from a clinical point of view, the main message is that the overwhelming majority in both groups favored yearly mammograms.
      In retrospect this is not surprising. These patients did not enter this study naive to the issue of breast cancer. Indeed, they have been exposed to consistent and high-profile media campaigns, endorsed by medicine and a variety of interest groups, that have indoctrinated them into the concepts that mammograms lead to early detection and early detection saves lives. The public is also experienced in seeing medical research later reversed. One study showed that approximately 30% of high-profile medical research is either contradicted or moderated within 2 years.
      • Ioannidis J.P.
      Contradicted and initially stronger effects in highly cited clinical research.
      In this context an element of skepticism seems prudent.

      Limitations

      The population for this study was primarily drawn from a white, middle-class, highly educated group of women from Massachusetts in which screening rates for breast cancer are among the highest in the country.
      Quality insights: clinical quality in primary care: Massachusetts statewide rates and national benchmarks.
      These women were already presenting for preventive care in the form of annual examinations. Consequently, populations with different health care beliefs and availability of screening may view the guidelines differently. The survey was performed within months of the release of the USPSTF guidelines and the public debate that followed. Time is likely to moderate some of these feelings and opinions.
      The vast majority of patients offered to participate in this study did volunteer. Those who did not gave time constraints as the reason, and most often these were patients who were arriving late for their appointment or who were in a rush to go elsewhere as soon as they were finished with their visit. We do not believe that these patients would have necessarily changed the results.

      Conclusions

      The findings of this study highlight the crucial role the media play in shaping public opinion regarding evidence-based medicine. The USPSTF is a core function in the movement to transform the practice of medicine to a stronger evidence base. However, the pathway to implementation of evidence-based guidelines may be more about improving American's health literacy and less about simply mining the science and making the recommendations.
      This survey reveals intense skepticism among women in the target audience for these recommendations. The job of communication and change must begin with an appreciation of the context, values, and beliefs of the group at which the change is being aimed. It would have been a realistic compromise, and in the end may have led to more public acceptance, if the recommendations were made to proceed with incremental changes in screening practices. As we strive to move toward a more evidence-based system of health care, it would be beneficial for policy makers, health care providers, and media outlets alike to recognize the crucial role the press plays in shaping patients' opinions, and this should be factored in when considering recommending change.

      Appendix

      Hello,
      You are being invited to participate in a study evaluating public opinion surrounding breast cancer screening. This study is anonymous and voluntary. Your decision to participate will in no way affect your health care. However, we encourage you to participate in this study because we believe that the information gained will help us to better counsel our patients about breast cancer screening.
      The US Preventative Service Task Force has recently changed its breast cancer screening guidelines. Women were previously recommended to have screening mammograms starting at age 40 years. The Task Force concluded that for women who are not at high risk of developing breast cancer, the risks of routine screening mammography (including false alarms and discovering cancers that may not grow and threaten the patient's health) outweigh the benefits (because early detection does not always lead to higher survival). It is therefore now recommending starting screening at age 50 years.
      We are conducting a study to better understand the public reaction to this change and how it can be influenced by the media. Please answer the following 9 questions and then read the attached article. After reading these article, please answer the second set of questions. After completing the questionnaire, please return it to the secure box as instructed by the office staff.
      • 1
        How old are you?_____________
      • 2
        Have you ever been diagnosed with breast cancer?
        Yes No
      • 3
        How do you classify your race?
        Black White American Indian/Alaskan Asian Native Hawaiian/Pacific Islander
      • 4
        What is the highest level of education you have completed?
        Did not finish high school High School 2 year college 4 year college Masters/graduate school
      • 5
        Approximately how many times have you had a mammogram?_____________
      • 6
        How many times have you had a further workup (imaging or biopsy) as a result of an abnormal mammogram?_____________
      • 7
        Has a close friend of yours ever been diagnosed with breast cancer?
        Yes No
      • 8
        Has a close family member of yours (mother, sister, aunt, grandmother) ever been diagnosed with breast cancer?
        Yes No
      • 9
        Approximately what percentage (0-100) of the women in the United States do you think will get breast cancer in their lifetime?_____________
      • 10
        Do you think YOUR chance of getting breast cancer is higher, lower, or about the same as this risk?
        Below average Average Higher than average
      Please read the attached article regarding the new screening changes and then answer the following questions.
      • 11
        Do you feel that you should have yearly mammograms in your 40s?
        Yes No
      • 12
        Do you feel that these new guidelines are safe?
        Yes No
      • 13
        Now that you are familiar with these new guidelines, would you feel comfortable delaying mammograms until the age of 50 years if your doctor felt this guideline was reasonable in your case?
        Yes No
      Davidson. Women's attitudes toward the 2009 USPSTF mammogram guidelines. Am J Obstet Gynecol 2011.

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        • Centers for Disease Control and Prevention
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        • Thun M.J.
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