JOURNAL OF WOMEN’S HEALTHVolume 17, Number 4, 2008© Mary Ann Liebert, Inc.DOI: 10.1089/jwh.2007.0331

Predictors of Mammography Screening AmongEthnically Diverse Low-Income Women

TERRY A. CRONAN, Ph.D.,1 IAN VILLALTA, B.A.,2 EMILY GOTTFRIED, B.A.,1YAVETTE VADEN, B.A.,1 MABEL RIBAS, B.A.,1 and TERRY L. CONWAY, Ph.D.1

ABSTRACT

Background and purpose: Breast cancer is the second leading cause of cancer deaths amongwomen in the United States. Minority women are less likely to be screened and more likelyto die from breast cancer than are Caucasian women. Although some studies have examinedethnic disparities in mammography screening, no study has examined whether there are eth-nic disparities among low-income, ethnically diverse women. The present study was designedto determine whether there are ethnic disparities in mammography screening and predictorsof screening among low-income African American, Mexican American, and Caucasian wo-men, and to determine whether the disparities and predictors vary across ethnic groups.

Methods: The participants were 146 low-income women who were Mexican American (32%),African American (31%), or Caucasian (37%). Statistical analyses were performed to assess therelationships between mammography screening during the past 2 years and potential pre-dictors of screening, both within ethnic groups and for the combined sample.

Results: The results varied depending on whether analyses combined ethnic groups or wereperformed within each of the three ethnic groups.

Conclusions: It is, therefore, important to examine within-group differences when examin-ing ethnic disparities in predictors of mammography.

527

INTRODUCTION

BREAST CANCER IS THE SECOND LEADING CAUSE ofcancer deaths among women in the United

States.1,2 According to the American Cancer So-ciety (ACS), 1 in 8 women will be diagnosed withbreast cancer within her lifetime.1

The U.S. Preventive Services Task Force rec-ommends mammography screening every 1–2years.3 Despite the fact that mammographyscreening is associated with a decrease in mor-tality rates, not all women obtain screeningwithin the recommended period.4 Smith-Bind-

man et al.5 found that 63%–68% of ethnic minor-ity women (African American, Latinas, Asian/Pacific Islanders, and Native Americans) but 72%of Caucasian women were screened for breastcancer at intervals of 1–2 years. They found thatminority women were significantly less likely tohave ever obtained preventive screening.

As suggested by Smith-Bindman et al.,5 in-creased mammography screening among AfricanAmerican and Hispanic women would reducebreast cancer mortality rates. Because mortalityrates for breast cancer are higher among womenfrom low-income and ethnic minority groups, it

1San Diego State University, San Diego, California.2Arizona State University, Tempe, Arizona.

is imperative to examine variables that predictscreening behavior in these populations in orderto design interventions that will increase overallscreening rates.6,7 Also, it is important to know ifthe factors that influence screening differ acrossethnic groups.

Consedine et al.,8 as well as Friedman et al.,9

have proposed and tested many hypotheses to ex-plain the discrepancies in mammography adher-ence between Caucasian and minority women.Studies assessing barriers to screening indicatethat Caucasian women are more likely to reportinconvenience, procrastination, and being toobusy, whereas African American women aremore likely to report worry and fear as barriers.8,9

Interestingly, African American women also re-ported greater overall cancer anxiety than didCaucasians. Thompson et al.10 studied AfricanAmerican and Latina urban women and foundthat perceived benefits, perceived barriers, per-ceived fear, and perceived susceptibility to can-cer were risk factors for low use of mammogra-phy screening. Barriers reported in other researchincluded lack of health insurance coverage, nousual source of care, the low priority placed onpreventive health screening behaviors relative toother priorities, previous negative healthcare ex-periences, lack of physician’s recommendation,nonadherence to follow-up issues, and lack ofknowledge.2,10–15 One possible predictor of dif-ferences in mammography screening among eth-nic groups is differences in income. Researchersalso need to examine whether other predictors ofmammography screening differ as a function ofethnicity.

The Health Belief Model (HBM) has often beenused as a theoretical framework for understand-ing the variables that influence the decision to bescreened for breast cancer. HBM variables thatare often measured in breast cancer screeningstudies include perceived susceptibility, per-ceived seriousness, perceived benefits, and per-ceived barriers.16,17 These HBM variables signifi-cantly predict breast cancer screening.18,19 Otherstudies have indicated that non-HBM factors(e.g., medical mistrust, having insurance or a reg-ular doctor) can also predict screening prac-tices.2,10–15

Medical mistrust signifies a lack of confidencein the treatment and information provided bymedical systems. Medical mistrust is negativelycorrelated with adherence to screening recom-mendations.13,20 Although mammography is an

extremely effective way to detect breast cancerearly, minority ethnic groups seem to have lessbelief in the healthcare system than do Caucasianwomen10; thus, it is not surprising that Latina andAfrican American women in the United States arethe least likely of all groups to undergo mam-mography examinations.20,21 Some studies havereported that Latinas and African American wo-men who are less acculturated have less trust inhealthcare systems because their cultural beliefsare inconsistent with conventional healthcareguidelines.10,14,21 Latinas expressed significantlyhigher levels of agreement with the belief thattesting was associated with disadvantages thandid other ethnic groups.22 These findings help toexplain why Latinas and African Americans re-ceive preventive services at much lower ratesthan do other women.20

Because ethnic differences may be attributableto differences in income, all participants in thepresent study were recruited from low-incomeareas to reduce income effects. For the presentstudy, African American, Mexican American, andCaucasian women were administered a survey toassess mammography screening and potentialpredictors of screening to examine differencesacross the three ethnic groups.

MATERIALS AND METHODS

Study design and setting

This research was designed as a three-groupcross-sectional survey study. Between Septemberand December 2005, Caucasian, African Ameri-can, and Mexican American women were ap-proached in several local shopping centers lo-cated in low-income areas and recruited toparticipate in the study by completing a self-ad-ministered survey. All procedures were reviewedand approved by the local university’s Institu-tional Review Board.

Procedures

ZIP codes were used to determine the averageincome levels, as well as the representation ofAfrican Americans, Mexican Americans, andCaucasians, in neighborhoods in San DiegoCounty. Census data from 2000 were used toidentify ZIP codes with populations of �20,000and median incomes �$50,000 (i.e., representingthe lower half of household incomes in San Diego

CRONAN ET AL.528

County). ZIP codes that had high representationsof each ethnic group were then selected. The median incomes for the African American andLatino populations were calculated, and ran-domly selected ZIP codes with matching medianincomes with the highest percentage of Cau-casians were chosen. This procedure was neces-sary because ZIP codes with large Caucasian pop-ulations have higher median incomes than thosewith large African American and Latino popula-tions. Shopping centers in the selected ZIP codeswere then identified.

Research assistants went to the shopping cen-ters and asked women to participate in the study.Shopping centers were available in all of the ZIPcodes selected, and recruiting in these centers al-lowed for consistency in sampling and data col-lection procedures. Women who appeared to befrom each of the targeted ethnic groups and to be�40 years of age were randomly selected (usinga random numbers table) at each location and ap-proached by a research assistant. Before the wo-man was asked to participate, the research assis-tant confirmed that she met the eligibilityrequirements: (1) �40 years of age, (2) AfricanAmerican, Mexican American/Latina, or Cau-casian, and (3) lived within the targeted ZIP code.

The women approached were told that the information collected from the questionnairewould be used to help design interventions thatwould increase the number of people who obtainmammography screening. Potential participantswere informed that their participation was vol-untary and that their answers were confidential.The women approached were also told that theywould be paid $5.00 for completing a three-pagequestionnaire. When an eligible woman agreedto participate, the research assistants asked her tocomplete the questionnaire and to place it in anenvelope to ensure confidentiality. In a few cases,participants asked the research assistants to readthe questionnaire to them. In these cases, the re-search assistants complied with the request. Theresearch assistants also answered participants’questions. A total of 146 southern California wo-men agreed to participate and completed thequestionnaire.

Measures

The survey included items to assess demo-graphic characteristics, screening behaviors, andpsychological factors potentially associated with

mammography screening. The survey was trans-lated from English to Spanish for participantswho preferred to read and answer the questionsin Spanish. Research assistants who were articu-late in reading, writing, and speaking in Spanishperformed the translations, and a group consen-sus was reached on the accuracy of the transla-tions.

Screening outcome

Participants were asked to specify whetherthey had ever obtained mammography (i.e., life-time use). If they reported having ever obtaineda mammography, they were asked to indicate thedate of their last screening. Using this informa-tion, a dummy-coded variable was created to in-dicate whether women had received a mammog-raphy within the past 2 years.

Predictors

Demographic characteristics. Age, ethnicity,years of education, household income, maritalstatus, and employment status were used to as-sess the demographic characteristics of the sam-ple. Two levels of education were coded: highschool diploma or less and some college orgreater. Three levels of income were coded:�$20,000, $20,000–$49,999, and �$50,000 andhigher.

Medical care. One dummy-coded variable in-dicated whether or not a doctor had recom-mended that the participant obtain mammogra-phy screening. Two questions assessing eachrespondent’s medical access were asked. One waswhether or not the participant had a regular doc-tor, and the second was whether or not the par-ticipant had health insurance.

Health beliefs. Several scales indicating partici-pants’ health beliefs were constructed.

Efficacy. Perceived efficacy of screening forbreast cancer was measured using three ques-tions with a 10-point response scale, ranging from1 (not at all) to 10 (extremely), measuring re-spondents’ confidence in its ability to detectbreast cancer, their confidence in mammogra-phy’s ability to prevent breast cancer, and theirconfidence that if breast cancer were found early,it could be cured. A mean score was computed.The efficacy scale’s internal consistency ranged

DISPARITIES IN MAMMOGRAPHY SCREENING 529

from � � 0.49 to � � 0.73 across the ethnicgroups.

Fear of cancer. Fear of developing breast can-cer was assessed, using an eight-item scale de-veloped by Champion et al.23 Participants re-sponded using a 5-point Likert scale ranging from1 (strongly disagree) to 5 (strongly agree). A meanfear score was computed. This scale had high re-liability, as indicated by the internal consistencyvalues (ranging from � � 0.93 to � � 0.95 acrossthe ethnic groups).

Susceptibility. Perceived susceptibility tobreast cancer was also measured, using a 5-pointLikert scale ranging from 1 (strongly disagree) to5 (strongly agree) to assess perceived beliefsabout personal susceptibility to breast cancer. Thethree items were: “It is likely that I will get breastcancer,” “My chances of getting breast cancer inthe next few years are great,” and “I feel I willget breast cancer sometime during my life.”24 Amean score was computed. The internal consis-tency ranged from � � 0.83 to � � 0.90 across theethnic groups.

Benefits of screening. A five-item scale wasused to assess the perceived benefits of obtainingmammography screening. Participants rateditems using a 5-point Likert scale ranging from 1(strongly disagree) to 5 (strongly agree). Two ex-amples of the items included in the scale were:“Having a mammogram is the best way for meto find a very small lump” and “Having a mam-mogram will decrease my chances of dying frombreast cancer.”24 A mean score was computed.The internal consistency ranged from � � 0.72 to� � 0.87 across the ethnic groups.

Barriers to screening. An 11-item scale devel-oped by Champion24 was used to assess the HBMconcept of perceived barriers to mammography.The mean of participants’ responses using a 5-point Likert scale that ranged from 1 (stronglydisagree) to 5 (strongly agree) was computed.Perceived barriers were defined as emotions,physical, and/or structural concerns related toobtaining a mammography screening.24 Such bar-riers included fear of finding breast cancer, em-barrassment/shame, or discomfort with the pro-cedure. The internal consistency of the barriersscale ranged from � � 0.83 to � � 0.92.

Medical mistrust. The 12-item Group-BasedMedical Mistrust scale, developed by Thompsonet al.,10 assessed mistrust of mainstream health-care systems and healthcare professionals, as wellas of the treatment provided to individuals of therespondent’s ethnic or racial group. Participantsrated items using a 5-point Likert scale rangingfrom 1 (strongly disagree) to 5 (strongly agree),and a mean scale score was computed. The scaleincluded such questions as: “People of my ethnicgroup should be suspicious of doctors and health-care workers” and “People of my ethnic groupshould be suspicious of modern medicine.”10 Theinternal consistency ranged from � � 0.67 to � �0.90 across the ethnic groups.

Statistical analysis

The Statistical Package for the Social Sciences(SPSS, Chicago, IL) for Windows® version 14.0was used for all statistical analyses. First, de-scriptive statistics (means, standard deviations[SD], and percentages) were calculated for allmeasures. Chi-square analyses for nominal vari-ables and analysis of variance (ANOVA) for con-tinuous variables were used to assess differencesin mammography screening and potential pre-dictors of screening across ethnic groups.

Second, the association between mammogra-phy screening (screened vs. not screened) withinthe previous 2 years and each potential predictorwas examined both in the total combined sampleand for each of the ethnic groups separately. As-sociations were assessed using chi-square analy-ses for nominal variables and independent groupt tests for continuous variables. Alpha for statis-tical significance was set at 0.05 a priori.

RESULTS

Response rates

Four hundred thirty-one women were asked toparticipate in the study. One hundred forty-six ofthe women met the eligibility requirements andagreed to participate. Thus, 33% of those ran-domly selected agreed to participate. Participa-tion rates did not differ as a function of ethnicity(chi-square � 3.03, p � 0.05).

Demographic characteristics

Participants’ mean age was 56.8 (SD � 10.99);ages ranged from 40 to 94. Thirty-seven percent

CRONAN ET AL.530

of the participants reported their ethnicity as Cau-casian (n � 54), 31% as African American (n �45), and 32% as Mexican American (n � 47). Onewoman categorized as African American speci-fied Jamaican. Two women who circled bothAfrican American and biracial were coded asAfrican American. Of those categorized as Mex-ican American, 1 woman specified Panamanianand another specified South American. Twenty-seven percent of the participants spoke Spanish.The participants’ mean number of years of edu-cation was 13.2 years, which corresponds to about1 year of college (SD 3.4), and their median totalfamily income level was between $20,000 and$29,000. Thirty-three percent of the participantswere married, and 50.7% were employed (28.6%were retired). Seventy-eight percent of the re-spondents reported having health insurance, and81.5% had a regular doctor.

Descriptives for screening outcome and predictors

Descriptive statistics for the total sample (allethnic groups combined), as well as for the sep-arate ethnic groups for each of the measures ex-amined, are provided in Table 1. Statistical as-sessments of differences across groups are alsoshown. For continuous variables, group meanswere compared and F tests were reported; fornominal variables, category counts were com-pared and chi-square was reported.

The screening variable examined was whethera participant reported having had mammogra-phy screening within the previous 2 years. In thetotal sample, 66.4% of women reported that theywere screened within this time frame. Althoughthe rates did not differ significantly across ethnicgroups (p � 0.29), 74.1% of Caucasian women re-ceived mammography screening during the past2 years compared with only 64.4% of AfricanAmerican and 59.6% of Mexican American wo-men.

Potential predictors of getting a mammogra-phy screening within the previous 2 years werecategorized into one of three groups: demo-graphic, medical care, and health beliefs (Table 1).

Demographics. The ethnic groups differed sig-nificantly on age, education, household income,and current employment. Caucasians were sig-nificantly (p � 0.001) older than both AfricanAmericans and Mexican Americans. MexicanAmericans were significantly (p � 0.001) more

likely to have only a high school or less educa-tion (68%) than Caucasians, who were more likelyto have completed at least some college (74%). Allthree ethnic groups were significantly (p � 0.001)different from each other on household income,with most Mexican Americans falling into thelowest household income category, most AfricanAmericans falling in the middle income category,and most Caucasians falling in the two highestincome categories. Caucasians were less likely(p � 0.004) than Mexican Americans to be cur-rently employed (Caucasians, on average, werecloser to retirement age, with a mean age of al-most 64 years old).

Medical care. The ethnic groups differed signif-icantly on two of the three medical care questions.Almost 89% of Caucasians reported havinghealth insurance, which was significantly (p �0.003) higher than Mexican Americans (just un-der 62% reporting health insurance). Similarly,Caucasians were more likely (p � 0.03) to saythey had a regular doctor than did MexicanAmericans (almost 91% vs. 70%, respectively).

Health beliefs. The ethnic groups differed sig-nificantly on three of six health beliefs scales.Mean scores on the Fear of Cancer scale weresignificantly (p � 0.02) higher for Mexican Amer-icans than for Caucasians, with African Ameri-cans falling between these two groups. All threegroups were significantly (p � 0.001) differentfrom each other on the mean barrier ratingscore, with Mexican Americans reporting thehighest mean barrier rating score, followed byAfrican Americans, with Caucasians reportingthe lowest mean barrier rating score. Lastly,Caucasians reported lower mean medical mis-trust than both African Americans and Hispan-ics (p � 0.001).

Associations between screening and predictors

Bivariate associations between mammographyscreening (screened vs. not screened) and eachpotential predictor were examined in both the to-tal sample as well as separately within each eth-nic group (Table 2). Significant associations be-tween mammography screening and thepotential predictors were as follows.

Demographics. Only two demographic variablesshowed significant (p � 0.05) associations with

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mammography screening in one or more of thegroups: age and education. Greater age was sig-nificantly related to getting screened in the totalsample, as well as in African Americans, with atrend (p � 0.08) in Caucasians, but age was notassociated with screening in Mexican Americans.There was a trend (p � 0.11) in the total samplefor women with at least some college educationto be more likely to get screened (72.2%) thanthose with only a high school education or less(59.7% screened); however, this relationship onlyreached statistical significance (p � 0.05) in theMexican American subgroup (80% with some col-lege screened vs. 50% with high school or lesswere screened). Although the relationship wasnot statistically significant, the pattern was thesame in Caucasian women but reversed inAfrican American women.

Medical care. All three medical care variableswere significantly associated with mammogra-phy screening in one or more of the group analy-ses. Having a regular doctor and having a doctorrecommend screening were significantly (p �0.01) associated with screening both in the totalsample and among Caucasian women and wereeither significant (p � 0.01) or showed a trend(p � 0.09) among African American and MexicanAmerican women. Having insurance was signif-icantly (p � 0.01) associated with screening in thetotal sample, showed a trend (p � 0.08) amongAfrican American women, but was not signifi-cantly related to screening among Caucasian orMexican American women.

Health beliefs. Although patterns for the totaland separate ethnic groups were inconsistent, allsix health beliefs scales were significantly (p �0.05) associated with screening in at least one ofthe group analyses.

Screening efficacy was significantly related tomammography screening in the total sample (p �0.01) and among Caucasian women (p � 0.03)and showed a trend in African American women(p � 0.06); for all groups, those who werescreened had a higher mean screening efficacyscore than those not screened.

Fear of cancer was significantly associated withscreening or showed a trend toward significancein Caucasian (p � 0.02), African American (p �0.01), and Mexican American women (p � 0.11).However, the association was not significant inthe total sample because the pattern of associa-

tion for African American women (not screenedwomen had a higher mean fear of cancer thanscreened women) was opposite from the patternin Caucasian and Mexican American women(screened women had a higher mean fear of can-cer than not screened women).

Perceived susceptibility to breast cancer wasassociated with mammography screening onlyamong Caucasian women (p � 0.05), withscreened Caucasian women having a highermean score than nonscreened women. There wasno relationship between perceived susceptibilityand screening in the total sample or amongAfrican American or Mexican American women.

The perceived benefits of screening scale wassignificantly associated with mammographyscreening only for Mexican American women(p � 0.04), with screened Mexican American wo-men having a higher mean score than non-screened women. The benefits scale was not sig-nificantly related to screening in the total sampleor among Caucasian or African American wo-men.

Although the barriers to screening scale wassignificantly (p � 0.01) associated with mam-mography screening during the previous 2 yearsin the total sample, it produced only a trend (p �0.06) in Mexican American women and was notsignificant in either Caucasian or African Amer-ican women. The highly significant associationfound for the total sample was produced by thepattern of these variables across the three ethnicsubgroups: Mexican American women had boththe highest mean barriers score (2.35) and thelowest percent screened (59.6%), African Ameri-can women were in the middle on both variables(1.93 and 64.4%), and Caucasian women had thelowest mean barriers score (1.53) and highest per-cent screened (74.1%) (Table 1). Thus, this patternproduced what appeared to be a negative associ-ation in the total sample, although there was lit-tle or no association within each ethnic subgroup.

The results for the medical mistrust scale weresimilar to those for the barriers to screening scale.Whereas medical mistrust was significantly (p �0.02) associated with screening in the total sam-ple, it produced only a trend (p � 0.08) in Mexi-can American women and was not significant ineither Caucasian or African American women. Aswith the barriers measure, the significant associ-ation found for the combined total sample wasproduced by the pattern of these variables acrossthe three ethnic subgroups, with Caucasian wo-

CRONAN ET AL.534

men reporting the lowest medical mistrust andhighest screening rate, African American womenin the middle on both variables, and MexicanAmerican women reporting the highest medicalmistrust and lowest screening rate.

DISCUSSION

The results indicated no statistically significantdifferences across low-income Caucasian, AfricanAmericans, and Mexican Americans in mam-mography screening over the past 2 years, al-though the pattern of rates replicated that re-ported by Smith-Bindman et al.5 Our generalpatterns of findings on mammography screeningrates are consistent with those of Miller andChampion13 and of Lee and Vogel,25 who alsofound that Caucasians were more likely to bescreened than African American and MexicanAmerican women. It is possible that we did notfind statistical differences in screening in the past2 years because our sample size was smaller thanthat in previous studies.

In the present study, the results appeared to bequite different when predictors of mammogra-phy screening were examined with ethnic groupscombined from the situation when the predictorswere examined within each ethnic group. For thecombined groups, the significant predictors wereage, health insurance, having a regular doctor,whether a physician recommended screening,perceived efficacy of screening, barriers to screen-ing, and medical mistrust. However, no predic-tors were consistently significant within all thethree ethnic groups. For Caucasians having a reg-ular doctor, receiving a doctor’s recommenda-tion, perceived efficacy of screening, fear of cancer, and perceived susceptibility predictedmammography screening. For African Ameri-cans, age, receiving a doctor’s recommendation,and fear of cancer predicted screening. Education(p � 0.051), having a regular doctor, and per-ceived efficacy of screening predicted mammog-raphy screening among Mexican Americans.

Thus, what predicts screening in the pooled sam-ple is different from what predicts screening withineach of the three ethnic groups. For example,screening efficacy predicts screening in the pooledsample, as well as in the Caucasian and MexicanAmerican samples; it is marginally significant inthe African American sample. In each sample, thedirection of the relationship is the same. In con-

trast, fear of cancer did not predict screening in thepooled sample, but it did in two of the three eth-nic groups. Interestingly, the direction of predic-tion was opposite for these two groups. In the Cau-casian sample, participants with higher fear scoreswere more likely to be screened than participantswith lower fear scores. Among African Americans,those with lower fear scores were more likely to bescreened than those with higher fear scores. Thedifferent directions of association found in theseethnic subgroups is consistent with previous re-search indicating mixed results across studies ex-amining emotional constructs as barriers and fa-cilitators of cancer screening.8,9

Previous research suggests that both barriers toscreening10,12 and medical mistrust10,20 are im-portant predictors of screening within the rec-ommended time. In the current study, both themean barrier rating and medical mistrust pre-dicted screening in the pooled sample, but nei-ther predicted screening in the subsamples, although there was a marginally significant as-sociation in the Mexican American group. Thus,it is important for researchers to examine within-ethnic group associations so that we can betterunderstand the important influences within eth-nic groups and tailor interventions to maximizeeffectiveness.

Limitations

In the present study, mammography use wasself-reported and, therefore, is subject to inaccu-rate recall.26–28 Another potential limitation ofthis study is that although women were ran-domly selected from those patronizing shoppingcenters, the $5.00 incentive to participate mayhave disproportionately interested poorer wo-men and thus masked the importance of incomein the analyses. In addition, although the studywas focused on examining predictors of mam-mography screening in low-income women, theparticipants were women residing in low-incomeZIP codes, and it might be argued that the rela-tively few women in the �$50,000 income cate-gory should have been excluded; however, 87%of the participants did report household incomes�$50,000, which is below the median in SanDiego County. In addition, income was not sig-nificantly associated with mammography screen-ing in either the combined sample or any of theseparate ethnic groups. This suggests that thestudy design and participant selection methods

DISPARITIES IN MAMMOGRAPHY SCREENING 535

were successful in eliminating income-related as-sociations with mammography screening. An-other limitation of this study was the relativelysmall number of participants within each ethnicgroup, which limited the power to detect effects.Future studies using larger samples should ex-amine the predictors of screening with multi-variate analysis methods to determine their independent contribution to explaining mam-mography screening rates.

CONCLUSIONS

The present study is unique in that the partic-ipants were randomly selected from low-incomeneighborhoods and the numbers of AfricanAmerican, Mexican American, and Caucasianparticipants were approximately equal. Findingsindicate that it is important to examine ethnicgroups separately to assess the predictors ofmammography screening and design interven-tions around those predictors. Our data confirmthe belief that interventions are needed to in-crease mammography screening rates, particu-larly among low-income, ethnically diverse wo-men, if we are to meet the Healthy People 2010 goalof having 70% of women aged �40 receive amammography within the previous 2 years.29 In-terventions especially need to target women whodo not believe in the efficacy of regular screeningand those who do not have regular medical care.It is also possible that if all women are to bescreened within the recommended times, weneed to offer free mobile screening in poor neigh-borhoods and increase the number of physicianswho recommend screening.

DISCLOSURE STATEMENT

No competing financial interests exist.

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Address reprint requests to:Terry Cronan, Ph.D.

Health Outcome Studies6505 Alvarado Road, Suite 110

San Diego, CA 92120

E-mail: tcronan@sunstroke.sdsu.edu

DISPARITIES IN MAMMOGRAPHY SCREENING 537