using the common sense model to understand perceived cancer risk in individuals testing for brca1/2...

PSYCHO-ONCOLOGY

Psycho-Oncology 14: 34–48 (2005)Published online 23 March 2004 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/pon.805

USING THE COMMON SENSE MODEL TOUNDERSTAND PERCEIVED CANCER RISK IN

INDIVIDUALS TESTING FOR BRCA1/2MUTATIONS

KIMBERLY KELLYa,*, HOWARD LEVENTHALb, MICHAEL ANDRYKOWSKIa, DEBORAH TOPPMEYERc,

JUDY MUCHc, JAMES DERMODYd, MONICA MARVINe, JILL BARANd and MARVIN SCHWALBd

aDepartment of Behavioral Science and Markey Cancer Control Program, University of Kentucky,Lexington, KY, USA

b Institute for Health, Health Care Policy, and Aging Research, Rutgers University, New Brunswick, NJ, USAcCenter for Human and Molecular Genetics, University of Medicine and Dentistry of New Jersey,

The New Jersey Medical School, Newark, NJ, USAdLIFE center-Cancer Risk Assessment and Genetic Counseling Program-Breast Oncology,

Cancer Institute of New Jersey, New Brunswick, NJ, USAeSpectrum Health, Grand Rapids, MI, USA

SUMMARY

The common sense model posits that individuals’ understanding of illness is based upon somatic symptoms and lifeexperiences and thus may differ significantly from the biomedical view of illness. The current study used the commonsense model to understand cancer risk perceptions in 99 individuals testing for BRCA1/2 mutations. Specifically, weexamined change from post-counseling to post-result in (1) absolute risk (risk of developing cancer in one’s lifetime)and (2) comparative risk (risk relative to the general population). Results indicated that absolute risk showed a trendsuch that those with a personal history of cancer receiving uninformative negative results reported decreasedabsolute risk. Further, individuals receiving uninformative negative results reported decreased comparative risk.Those with no personal cancer history receiving informative negative results did not decrease in risk over time nordid their risk differ from those with a personal cancer history, evidencing unrealistic pessimism regarding their risk ofcancer. The reasons provided for individuals’ risk perceptions could be classified in terms of attributes of thecommon sense model and included the: (1) causes of cancer (e.g. family history, mutation status); (2) control or cureof cancer through health behaviors and/or surgery; and (3) perceived timeline for developing cancer (e.g. time left inlife to develop cancer). We conclude that key to developing interventions to improve understanding of cancer riskand promoting effective cancer control mechanisms is an understanding of the specific reasons underlyingindividuals’ perceptions of cancer risk. Copyright # 2004 John Wiley & Sons, Ltd.

INTRODUCTION

Having a BRCA1/2 mutation is associated withincreased risk of breast-ovarian cancer, andproviding up-to-date and accurate risk estimatesto the consultand is one of the main goals of

genetic counseling in the context of BRCA1/2mutations (Baty et al., 1997; Lerman et al., 1997).Although genetic counseling and risk educationhas been shown to improve the accuracy of cancerrisk estimates (Meiser and Halliday, 2002), riskperceptions often continue to be inaccurate aftercounseling (e.g. Evans et al., 1994; Kelly et al.,2003). In addition to a tendency to be inaccurate intheir assessment of personal lifetime cancer risk,individuals from families with a history of breast-ovarian cancer often have difficulty using empiricalrisk information to guide decisions regarding

Received 23 July 2003Copyright # 2004 John Wiley & Sons, Ltd. Accepted 26 January 2004

*Correspondence to: Department of Behavioral Science, Uni-versity of Kentucky, College of Medicine, College of MedicineOffice Building, Lexington, KY 40536-0086, USA. E-mail:[email protected]

cancer health-related actions appropriate to theirempirical risk level following genetic counselingand testing (Lerman et al., 2000). The discordanceamong empirical risk, perceived risk, and subse-quent health behavior has been demonstrated in avariety of cancer-control contexts including che-moprevention for breast cancer (Bastian et al.,2001) and prophylactic oophorectomy (Hurleyet al., 2001). Improved understanding of howindividuals estimate their personal cancer risk iscritical to understanding the often puzzling re-lationship among empirical risk, subjective risk,and health behavior.

Most efforts to measure cancer risk perceptionshave used one of two different methods, compara-tive and absolute perceived risk. Absolute riskassesses a discrete estimate of risk. Some types ofabsolute perceived risk estimates (i.e. those whichare depicted in terms of probability) may allowcomputation of precise discrepancies betweenperceived and empirical risk estimates, as empiri-cal risk estimates are typically presented using aprobability format (e.g. Berry et al., 1997; Parmi-giani et al., 1998). Studies making such compar-isons find individuals at risk for BRCA1/2mutations tend to be inaccurate in their prob-ability estimates of having a mutation (Blumanet al., 1999; Kelly et al., 2003) and in their lifetimerisk of breast cancer (Evans et al., 1994; Hopwoodet al., 1998; Watson et al., 1999; Cull et al., 1999;Burke et al., 2000; Bish et al., 2002) even afterextensive counseling. Most of these studies reportthat the majority of consultands overestimate risk,and although consultands become more accuratefollowing counseling, many continue to over-estimate risk. Further, one study (Lerman et al.,1997) found that perceived risk of having aBRCA1 mutation decreased on a 4-point scalefollowing genetic counseling, presumably fromoverestimating risk before counseling and becom-ing more accurate after counseling.

Comparative perceived risk, assessing risk incomparison to another individual or group, is lesscommonly assessed before and after geneticcounseling for BRCA1/2 mutations. For example,Watson et al. (1999), in addition to askingconsultands their absolute perceived risk, enquiredabout comparative perceived risk on a 5-pointscale. They found that comparative perceived riskrelative to the general population did not changein response to genetic counseling. Also, highercomparative perceived risk was correlated withhigher empirical risk. Similarly, Bish et al. (2002)

found that perceived risk did not change over timewith assessments before counseling and at 2 weeks,6 and 12 months after genetic counseling. Those atlower empirical risk had lower perceived risk andvice versa. Further, Schwartz et al. (2002) exam-ined dichotomized comparative perceived risk andfound no change from 1 to 6 month post-resultand no impact of type of genetic test result(positive vs uninformative). We identified nostudies examining (1) absolute and comparativeperceived risk before and after genetic testing(quantitative analysis) and (2) the reasons under-lying comparative and absolute perceived risk(qualitative analysis).

Model to understand risk perceptions

Research examining cancer risk perceptions inindividuals at risk for BRCA1/2 mutations mayfail to conceptualize and assess risk in ways thatwill capture the individual patient’s experience ofrisk. The difficulty in conceptualizing risk innumeric terms may reflect issues of numeracy(i.e. inability to understand probabilities or totranslate abstract, population values to values forthe individual person) (Schwartz et al., 1997), ormay reflect unexamined psychological processes.Moreover, individuals respond to empirical riskestimates and translate these risk estimates intoabsolute and comparative perceived risk estimatesin unknown ways. The processes by which thisoccurs might be illuminated by using the commonsense model (Leventhal et al., 1992, 1997) toexamine an individual’s own understanding ofrisk. Although this model has been used tounderstand lay conceptualizations of healththreats (e.g. Lau et al., 1983), including pediatricgenetic disorders (Shiloh and Berkenstadt, 1992);this model has not been previously used tounderstand lay conceptualizations of familial/hereditary cancers as advocated by Decruyenaereet al., (2000) nor to understand subjective esti-mates of lifetime cancer risk.

Five attributes characteristic of the commonsense model have been delineated: (1) the identity/label of the health threat (i.e. the name of thecondition); (2) the timeline of the health threat(e.g. acute, chronic, or cyclic); (3) the consequencesof the health threat (e.g. physical, economic,psychological, or social); (4) the causes of thehealth threat (e.g. inheritance or environment);and (5) the control or cure of the health threat

COMMON SENSE MODEL AND PERCEIVED RISK 35

Copyright # 2004 John Wiley & Sons, Ltd. Psycho-Oncology 14: 34–48 (2005)

(e.g. health behavior or surgery) (Leventhal et al.,1992, 1997; Weinman et al., 1996). The informa-tion represented in each of these five domains mayinfluence perceptions of risk, shape how percep-tions of risk are expressed, and affect the relation-ship of perceived risk to behavior. For example,individuals may not be able to give a meaningfulprobabilistic estimate of risk, but they may be ableto express their sense of risk in terms of the reasonsthat they feel at risk. Thus, a woman may believeshe is at high risk for breast cancer ‘because mymother had breast cancer’ (cause component) orshe may believe she is at low risk for breast cancerbecause ‘I’ve had a prophylactic mastectomy, andthis lowers my risk of breast cancer,’ (control orcure component).

In light of the difficulties apparent in the use ofempirical risk information and the generation ofabsolute and comparative perceived risk estimates,effort should be devoted to understanding howindividuals conceptualize risk and what informa-tion individuals use to form their own subjectiveestimates of risk. The present study examinedestimates of absolute and comparative perceivedcancer risk, their change from post-counseling topost-results, and the rationale for these estimatesof perceived risk in the context of genetic testingfor individuals at risk for BRCA1/2 mutations. Wehypothesize that: (1) individuals with a positivetest result will report increased absolute andcomparative perceived cancer risk, and individualswith negative test results will report decreasedabsolute and comparative perceived cancer risk,(2) no personal cancer history and a negative testresult will be associated with lower absolute andcomparative perceived cancer risk, and (3) reasonsunderlying absolute and comparative perceivedrisk can be categorized with regard to fiveattributes of the common sense model (causes,consequences, control or cure, timeline, and label)reported by Leventhal et al. (1992, 1997) and willchange over time.

METHOD

Participants

A total of 112 Ashkenazi Jewish individuals (99women and 13 men) from approximately 70families participated in a prospective, longitudinalstudy investigating response to counseling and

testing for BRCA1/2 mutations. All participantsself-identified as of Ashkenazi Jewish descent. Forindividuals with a family history of cancer(whether or not they had a personal history ofcancer), the line of transmission was traced to anAshkenazi Jewish grandparent. For individualswith a personal history with no family history(N ¼ 12) at least one grandparent was of Ashke-nazi Jewish descent. Additionally, participants metone of the criteria noted below. Participation waslimited to the Ashkenazi Jewish populationbecause the high prevalence of these mutations inthis population made testing more feasible than inother populations. The criteria were designed toinclude only those individuals whose familyhistories were suggestive of an inherited predis-position to breast and/or ovarian cancer. Thisincreased the probability of finding a BRCA1 orBRCA2 mutation.

Personal history. Women with a previous diag-nosis of cancer were eligible if: (1) their breastcancer was diagnosed before the age of 50; (2) theyhad breast cancer at any age and had at least onefirst or second degree relative with either breastcancer diagnosed before the age of 50 or ovariancancer at any age; or (3) they had been diagnosedwith ovarian cancer at any age. Men with breastcancer were eligible regardless of their age atdiagnosis.

Family history but no personal history. Men andwomen were eligible if they: (1) had one firstdegree relative with breast cancer before the age of50, ovarian cancer at any age, and another first orsecond degree relative with breast cancer beforethe age of 60 or ovarian cancer at any age; (2) hadboth a paternal second degree relative with breastcancer before the age of 50 or ovarian cancer atany age and a paternal second degree relative withbreast cancer before the age of 60 or ovariancancer at any age; (3) were first degree relatives ofa male with breast cancer at any age; (4) were firstor second degree relatives of an individual with adocumented BRCA1 or BRCA2 mutation.

Procedure. Participants were recruited for thestudy through newspaper articles, letters to localoncologists and gynecologists, and presentationsat Jewish community organizations and breastcancer interest groups. Interested individualscontacted a board-certified or board-eligible

K. KELLY ET AL.36


genetic counselor who was a member of theresearch team. An effort was then made to confirmthe individual’s medical records in order toconfirm study eligibility. Eligible participantsreceived genetic counseling and testing free ofcharge.

Prior to initiating the genetic counseling session,the genetic counselor reviewed and obtainedwritten consent for the survey study. Participantscompleted a biographical data form as part of alarger study to assess the impact of geneticcounseling and testing for BRCA1/2 mutations.Genetic counseling began with a review of thefamily cancer history and personal risk factors forbreast and ovarian cancer. This was followed byan educational component consistent with anoutline of a standard cancer genetic counselingsession provided by the Familial Cancer RiskCounseling Special Interest Group of the NationalSociety of Genetic Counselors (National Society ofGenetic Counselors, 2003). Genetic counselingaddressed several topics including: mechanismsof cancer inheritance, meaning of a negative testresult, meaning of a positive test result, risks andbenefits associated with mutation testing, efficacyof health interventions to reduce cancer risk, andrisks associated with BRCA1/2 mutations (Kellyet al., 2003). Specifically, a pie chart with ‘10%’written on it was used to illustrate the percentageof breast and ovarian cancer due to inherited genesin the general population. The percentage risk ofseveral cancers (including prostate and coloncancer but focusing on breast and ovarian cancer)with BRCA1 and BRCA2 mutations was illu-strated by a bar graph with the correspondingpercentage risk written numerically. For example,the breast cancer risk with a BRCA1 or BRCA2mutation for women may be as high as 85% buthas more recently been adjusted to 60% (Struew-ing et al., 1997). Personalized percentage riskestimates were not given during this session.Eligible participants not previously diagnosed withcancer were encouraged to be tested in conjunctionwith or after a relative with a history of breast orovarian cancer. The genetic counseling session was1–2 h in length and was audiotaped to assessconsistency of delivery.

A telephone interview (Time 1: post-counselinginterview) was conducted 1–2 days following thegenetic counseling session by the first author or aresearch assistant. Information collected at Time 1included both quantitative and qualitative assess-ments of perceived risk as part of a larger interview

investigating the impact of genetic counseling andtesting for BRCA1/2 mutations. Approximately 1day after the Time 1 interview, the geneticcounselor telephoned the study participant andinquired about the decision to proceed withmutation testing. If the participant elected toundergo mutation testing, an additional consentform was provided and signed prior to testing.Blood was drawn from all individuals electingmutation testing, and DNA was analyzed forcommon, recurrent BRCA1 and BRCA2 muta-tions seen in the Ashkenazi Jewish population(Tonin et al., 1996).

One to three months following the decision totest, participant’s who elected mutation testingwere notified of their test results by the geneticcounselor in a face-to-face meeting. Implica-tions of results both for the participant and forrelatives were reviewed. Individuals who testedpositive for a BRCA1 or BRCA2 mutation wereencouraged to notify relatives so they couldconsider mutation testing. A negative result foran individual where a mutation had not beenlocated in the family was essentially uninformativesince other mutations in BRCA1, BRCA2 or otherbreast cancer genes may still be present. They weretold that their risk was still elevated above thegeneral population. However, individuals with aninformative negative result were told their risk ofbreast cancer was equivalent to the generalpopulation (approximately 10%). Cancer controloptions were discussed and provided to theparticipant’s primary care physician if the partici-pant requested.

A second telephone interview (Time 2: post-result interview) was conducted 1 week afterreceipt of genetic test results by the first authoror a research assistant not involved in their care.Individuals who did not wish to receive genetic testresults (N ¼ 13) were interviewed at a similar timepoint (1–3 months after genetic counseling), butthey are not included in the present study.Information collected in the Time 2 interviewincluded both quantitative and qualitative assess-ments of perceived risk as part of a larger interviewinvestigating the impact of genetic counseling andtesting for BRCA1/2 mutations.

Measures

Background information. A biographical datasheet collected information regarding age, gender,



education, marital/partner status, annual familyincome, and information regarding the parti-cipants’ personal history of cancer (Yes/no, andif so, what specific diagnoses). This informationwas collected before genetic counseling.

Cancer risk perception. Perceptions of personallifetime cancer risk were assessed by two items.One item (Absolute perceived risk) asked partici-pants to indicate whether or not they woulddevelop cancer in their lifetime: ‘Do you feel youwill be among those who get cancer (again) orthose who do not?’ Response options were ‘yes’ or‘no.’ The use of a binary risk item was suggestedby the early qualitative work of Lippman-Handand Fraser (1979). This question was also followedby an open-ended question asking participants toindicate why they responded as they did.

A second item (Comparative perceived risk)asked participants to compare their personallifetime risk for breast cancer to that of otherwomen (or men if the respondent was male): ‘Doyou think your odds of getting breast cancer(again) are the same or different than those ofother women (men)?’ Response options included‘higher,’ ‘the same,’ or ‘lower.’ A similar compara-tive risk item has been used to assess breast cancer(Lipkus et al., 2000) and colorectal cancer (Lipkuset al., 1999) risk. A follow-up, open-ended ques-tion asked participants to indicate why theyresponded as they did.

Statistical analysis

Means, standard deviations, and other indicesof normality were generated to describe the dataand prepare the data for statistical analysis.A number of individuals (Time 1: 7.9%; Time 2:13.2%) could not report absolute perceived risk inbinary terms. Instead, they either reported theywere unsure whether or not they would get canceror gave an alternative perceived risk estimate suchas a percentage. These individuals were given anintermediate code between NO and YES. Hence, itwas determined that rather than perform a seriesof non-parametric tests for a binary response tothe comparative perceived risk item, repeatedmeasures analysis of variance would be used fortesting hypotheses of both comparative andabsolute perceived risk as these had trichoto-mous (Comparative: higher, same, lower and

absolute: yes, intermediate, no), incrementally-scaled responses.

In preparation for qualitative analysis, aresearch assistant prepared a list of all open-endedresponses given by participants in response to thetwo open-ended questions assessing reasons un-derlying cancer risk perceptions. This list was thencoded by the first author, who was blind toparticipant mutation status and cancer history,to reflect specific attributes of the common sensemodel. First, the range and nature of responseswere reviewed. Second, responses were categorizedinto one of five relevant attributes of the commonsense model (Causes, control or cure, conse-quences, timeline, and label). Causes includedreasons such as hereditary genes and environment.Past surgery and past or presently engaged-inhealth behaviors such as diet and exercise werecoded as control or cure. Consequences wouldinclude such reasons as the economic or psycho-social impact of the risk. Reasons includingassessments of current age in relationship toanticipated cancer onset would be coded as time-line. The attribute of identity/label was extendedfor the current study. In the current study, we didnot ask about how they conceptualized a healththreat (e.g. breast cancer). Rather, we wereinterested in risk. Hence, luck and other prob-ability terms for ‘risk’ were included as label.Finally, a series of non-parametric repeatedmeasures analyses (Wilcoxon-signed ranks tests)were computed to determine change in thefrequency of mention of causes, control or cure,consequences, timeline, and labels from Time 1 toTime 2.

RESULTS

One hundred and twelve individuals of AshkenaziJewish descent presented for genetic counseling,and 99 proceeded with genetic testing. Only thoseproceeding with genetic testing are included here.Genetic test results were positive for 23 (23%)(mutation present), and negative (mutation notpresent) for 76 (76%). Negative results wereinformative (the individual was negative for themutation found in the family) for 10 of the 76participants and uninformative (the individualmay have a mutation for which we did not test)for 66. Table 1 shows the background data ofindividuals receiving positive and negative results.

K. KELLY ET AL.38


Change over time in cancer risk perceptions:absolute perceived cancer risk

At Time 1 and Time 2, most individuals believedthey would develop cancer (Time 1: 58.4%;Time 2: 53.8%) with a large minority believingthey would not develop cancer (Time 1: 33.7%;Time 2: 33.0%). A number of individuals wereuncertain and were given an intermediate code(Time 1: 7.9%; Time 2: 13.2%). A three-wayrepeated measures analysis was performed to testthe hypotheses: (1) individuals with a positive testresult will report increased absolute perceivedcancer risk, and individuals with negative muta-tion test results will report decreased absoluteperceived cancer risk, (2) no personal cancerhistory and a negative test result will be associatedwith lower Absolute perceived cancer risk. Priorhistory of breast and/or ovarian cancer (yes vs no)and test result (positive, informative negative,uninformative negative) were between groupsfactors, and time (post-counseling vs post-results)was the within groups factor. The results indicatedno main effects for time ðFð1; 82Þ ¼ 0:07;NSÞ,prior cancer history (Fð1; 82Þ ¼ 0:97, NS), or testresult (Fð2; 82Þ ¼ 0:90, NS), and results indicatedno interaction effects for time � prior historyof cancer (Fð1; 82Þ ¼ 0:01, NS), time � testresult (Fð1; 82Þ ¼ 1:01, NS), or prior history ofcancer � test result (Fð1; 82Þ ¼ 0:35, NS). How-ever, a trend for a time � test result � cancerhistory interaction was found (Fð1; 82Þ ¼ 3:23;p ¼ 0:08). A post hoc contrast revealed thatparticipants with a personal cancer history receiv-

ing an uninformative negative result decreased inabsolute perceived risk at Time 2 ðM¼ 1:07 ðS:E:¼ 0:17ÞÞ relative to the Time 1 interview ðM¼ 1:47ðS:E: ¼ 0:17Þ; Fð1; 82Þ ¼ 4:01, p ¼ 0:05).

Reasons underlying cancer risk perceptions:absolute perceived cancer risk

As seen in Table 2, the most commonly citedreason for believing that they would developcancer included family history (Time 1: 17/52,Time 2: 15/49) and personal history (Time 1: 12/52, Time 2: 4/49). Those who would not committo a ‘yes’ or ‘no’ response most commonly citedhaving a mutation (Time 1: 3/7, Time 2: 0/7) andsurgery (Time 1: 0/12, Time 2: 2/12) for theirfeelings of risk. Most common reasons for believ-ing that they would not develop cancer includedoptimism/positive attitude (Time 1: 9/30, Time 2:8/30) and diet, exercise, or vitamins (Time 1: 9/30,Time 2: 7/30). Least commonly expressed reasonsfor believing that they would develop cancerincluded having a recurrence (Time 1: 0/52, Time2: 1/49) or if not having breast cancer, havinganother type (Time 1: 0/52, Time 2: 1/49). Thosewho would not commit to a ‘yes’ or ‘no’ responseleast commonly cited family history (Time 1: 0/7,Time 2: 1/12), personal history (Time 1: 0/7,Time 2: 1/12), and instinctive feeling (Time 1: 1/7,Time 2: 0/12). Least common reasons for believingthat they would not develop cancer includeddiagnosed with cancer at a young age (Time 1:1/30, Time 2: 0/30), statistics (Time 1: 1/30,

Table 1. Comparison of those receiving positive and negative test results on demographic variables

Positive Negative

Age M=49.8 (S.D.=13.9) M=50.0 (S.D.=11.9) t(2,92)=�0.05, NS

Amount of school M=16.4 (S.D.=2.5) M=17.5 (S.D.=1.7) t(2,92)=�1.94, p=0.06

Annual family income M=7.3 (S.D.=1.0) M=7.0 (S.D.=1.7) t(2,89)=1.03, NS

Marital Status w2(3,n=94)=1.95, NS

* Single, never married 4% 1%

* Married 65% 18%

* Separated/divorced 3% 1%

* Widowed 7% 0

History of breast or ovarian cancer w 2(1,n=98)=0.17, NS

* No 14% 43%

* Yes 9% 34%

History of cancer w 2(1,n=97)=0.23, NS

* No 13% 41%

* Yes 9% 36%



Time 2: 0/30), luck (Time 1: 1/30, Time 2: 0/30),being Ashkenazi Jewish (Time 1: 1/30, Time 2: 0/30), knowledge about cancer (Time 1: 1/30, Time2: 0/30), and gender (Time 1: 0/30, Time 2: 1/30).

Qualitative data regarding absolute perceivedrisk was analyzed to test our hypothesis that (3)reasons underlying absolute perceived risk can becategorized with regard to five attributes of the

common sense model and will change over time.At Time 1, 24 reasons were identified for absoluteperceived risk, and at Time 2, 21 reasons wereidentified. Table 3 shows the reasons codedaccording to the relevant attribute from thecommon sense model. Eight reasons were classifiedas causes (has mutation, no mutation, other genemutations, environment, family history, personal

Table 2. Reasons for absolute perceived cancer risk

Item Time 1 Time 2

Will develop cancer (Time 1: N=52; Time 2: N=49)

Family history 17 (33%) 15 (31%)

Personal history 12 (23%) 4 (8%)

Gene status (Have or will be found to have a BRCA1/2 mutation) 11 (21%) 2 (4%)

Gene status (Have or will be found to have another mutation) 2 (4%) 2 (4%)

Environment (e.g. We have so much pollution here) 4 (8%) 1 (2%)

Type of previous cancer 3 (6%)

Recurrence 1 (2%)

Diet, stress, smoking, or lack of exercise 5 (10%)

Drugs 1 (2%)

A lot of Time left in life/diagnosed with cancer at young age (e.g. I have a lot of

Time left in life to develop cancer)

2 (4%) 3 (6%)

Statistics 4 (8%) 2 (4%)

Luck 2 (4%) 1 (1%)

Instinctive feeling, pessimism, or optimism (e.g. It’s just a feeling I have) 8 (15%) 3 (6%)

Risk for other cancer (e.g. If I don’t get breast cancer, I’ll get some other type) 1 (2%)

Intermediate (Time 1: N=7; Time 2: N=12)

Family history 1 (8%)

Personal history 1 (8%)

Gene status (Do not have or will not be found to have a mutation) 1 (14%) 1 (8%)

Gene status (Have or will be found to have a BRCA1/2 mutation) 3 (43%)

Environment 1 (14%)

Surgery 2 (17%)

Instinctive feeling 1 (14%)

Will not develop cancer (Time 1: N=30; Time 2: N=30)


Personal history (e.g. I’ve had cancer once, and I’m not going to get it again) 2 (7%) 3 (10%)

Gene status (Have or will be found to have a BRCA1/BRCA2 mutation 1 (3%) 2 (7%)

Gene status (Do not have or will not be found to have a mutation) 4 (13%)

Environment 2 (7%)

Type of previous cancer 2 (7%)

Diet, exercise or vitamins 9 (30%) 7 (23%)

Surgery or drugs (e.g. I’ve had both breasts removed) 5 (17%) 2 (7%)

Screening 2 (7%)

Diagnosed with cancer at young age 1 (3%)

Statistics 1 (3%)

Luck 1 (3%)

Instinctive feeling, optimism, emotional openness, or positive attitude (e.g. I’m optimistic) 9 (30%) 8 (27%)

Ethnicity: Ashkenazi Jewish 1 (3%)

Knowledge about cancer (e.g. I know a lot about cancer) 1 (3%)

Gender (male) 1 (3%)

K. KELLY ET AL.40


history, type of previous cancer and recurrence).Seven reasons were classified as control or cure(diet, vitamins, preventive drugs, smoking, lack ofexercise, surgery, and screening). Two reasonswere classified as timeline (a lot of time left in lifeto develop cancer and diagnosed with cancer at ayoung age). Two reasons were classified as Labels(statistics and luck). Five items did not appear tobe consistent with elements from the commonsense model (being Ashkenazi Jewish, positiveattitude, instinctive feeling, pessimism, and knowl-edge about cancer).

As no consequences were mentioned, a series ofWilcoxon signed ranks test were computed todetermine change in the frequency of mention ofcauses, control or cure, timeline, and labels. Nochange was found in the frequency of mention ofcontrol or cure (z ¼ �1:21; NS), timeline(z ¼ 0:01; NS), or labels (z ¼ �1:67; NS). How-ever, a change was detected in the frequency ofmention of causes such that more people men-tioned causes at Time 1 (M ¼ 0:67 (S:D: ¼ 0:67)than Time 2 ðM ¼ 0:48ðS:D: ¼ 0:73Þ, z ¼ �2:48;p ¼ 0:01Þ.

Table 3. Common sense model classifications of absolute perceived cancer risk

Item Time 1 #

Reporting

Time 2 #

Reporting

Will develop cancer

Causes: 46 28

(family history, personal history, having an inherited mutation, environment factors, type

of previous cancer, recurrence)

Control or cure: 6

(poor diet, stress, smoking, lack of exercise, drugs)

Timeline: 2 3

(a lot of time left in life, diagnosed with breast cancer at young age)

Label: 6 3

(statistics, luck)

Not classified:

Emotional (Instinctive feeling, pessimistic) 8 3

If not breast cancer some other type 1

Intermediate

Causes: 5 3

(family history, personal history, having an inherited mutation, no inherited mutation,

environment)

Control or cure: 2

(surgery)

Not classified:

Emotional (Instinctive feeling) 1

Will not develop cancer

Causes: 9 12

(family history, personal history, having an inherited mutation, no inherited mutation,

environmental factors, type of previous cancer)

Control or cure: 16 9

(diet, exercise, vitamins, surgery, drugs, screening)

Timeline: 1

(diagnosed with breast cancer at young age)

Label: 2

(statistics, luck)

Not classified:

Emotional (Instinctive feeling, optimism, openness) 9 8

Ethnicity: Ashkenazi Jewish 1

Gender (male) 1

Knowledge about cancer 1



Change over time in cancer risk perceptions:comparative perceived breast cancer risk

At Time 1 and Time 2, most individuals believedtheir risk was higher than the general population(Time 1: 78.5%; Time 2: 67.4%) with a minoritybelieving their risk the same as (Time 1: 9.7%;Time 2: 22.8%) or less than (Time 1: 11.8%; Time2: 9.8%) the general population. A three-wayrepeated measures analysis was performed to testthe hypotheses: (1) individuals with a positive testresult will report increased perceptions of com-parative perceived cancer risk, and individualswith negative test results will report decreasedcomparative perceived risk and (2) no personalcancer history and a negative test result will beassociated with lower comparative perceived risk.Prior history of breast and/or ovarian cancer (yesvs no) and test result (positive, informativenegative, uninformative negative) were betweengroups factors, and time (post-counseling vspost-results) was the within groups factor. Theresults indicated no main effects for time(Fð1; 86Þ ¼ 0:45, NS), prior history of breast and/or ovarian cancer (Fð1; 86Þ ¼ 0:51, NS), or testresult (Fð2; 86Þ ¼ 0:03, NS), and results indicatedno interaction effects for time � prior history ofbreast and/or ovarian cancer (Fð1; 86Þ ¼ 0:91,NS), prior history of breast and/or ovariancancer � test result (Fð1; 86Þ ¼ 0:17, NS), or time� prior history of breast and/or ovariancancer � status (Fð1; 86Þ ¼ 0:43, NS). However,a significant time � test result interaction wasfound ðFð1; 86Þ ¼ 3:68; p ¼ 0:03Þ. A post hoc con-trast revealed that participants receiving uninfor-mative negative results reported reducedperceptions of personal breast cancer risk at theTime 2 interview ðM ¼ 2:51ðS:E: ¼ 0:09ÞÞ relativeto the Time 1 interview ðM ¼ 2:73ðS:E: ¼ 0:08Þ;Fð1; 86Þ ¼ 6:09, p ¼ 0:02Þ.

Reasons underlying cancer risk perceptions:comparative perceived cancer risk

As shown in Table 4, participants expressedmultiple reasons for believing their lifetime risk forbreast cancer was the same or different than thegeneral population. The most commonly citedreasons for believing risk to be higher than thegeneral population included family history (Time1: 44/73; Time 2: 29/62) and personal history(Time 1: 25/73; and Time 2: 26/62). The most

commonly cited reason for believing risk to be thesame as the general population was that they hadno inherited mutation (Time 1: 1/9; Time 2: 12/21).The most commonly cited reason for believing riskto be lower than the general population wassurgery, drugs, or treatments (Time 1: 11/11; Time2: 7/9). Least commonly cited reasons for believingrisk to be higher than the general populationincluded having other hereditary mutations (Time1: 0/73; Time 2: 1/62), environment (Time 1: 1/73;Time 2: 0/62), and getting older (Time 1: 1/73;Time 2: 0/62). Having a mutation (Time 1: 0/9,Time 2: 1/21), environment (Time 1: 1/9, Time 2:0/21), young age (Time 1: 1/9, Time 2: 0/21), andstatistics (Time 1: 1/9, Time 2: 0/21) were leastcommonly cited as reasons for believing risk to bethe same as the general population. The leastcommonly cited reason for believing risk to belower than the general population was optimism(Time 1: 1/11, Time 2: 0/9)

Qualitative data regarding comparative per-ceived risk was analyzed to test our hypothesisthat (3) reasons underlying comparative perceivedrisk can be categorized with regard to fiveattributes of the common sense model and willchange over time. At Time 1, 19 reasons wereidentified for comparative perceived risk, and 13reasons were identified at Time 2. These were thencoded according to the relevant attribute from thecommon sense model. Six reasons were classifiedas causes (family history, personal history, type ofprevious cancer, environment, mutation, andgenetics). Five reasons were classified as controlor cure (diet, surgery, drug treatments, radiation,and exercise). Three reasons were classified astimeline (diagnosed prior to 50/menopause, gettingolder, and young age). Two reasons were classifiedas labels (statistics and luck). Two items did notappear to be consistent with elements from thecommon sense model (being Ashkenazi Jewish andoptimistic).

As no consequences were mentioned, a series ofWilcoxon signed ranks test were computed todetermine change in the frequency of mention ofcauses, control or cure, timeline, and labels. Nochange was found in the frequency of mention ofcauses (z ¼ �1:00; NS) and control or cure(z ¼ �1:51; NS). However, there was a trendindicating that the frequency of mention oftimeline decreased from Time 1 ðM ¼ 0:05ðS:D: ¼ 0:27Þ to Time 2 ðM ¼ 0:0ðS:D: ¼ 0:0Þ; z ¼�1:89; p ¼ 0:06Þ and a trend indicating that thefrequency of mention of labels decreased from

K. KELLY ET AL.42


Time 1 ðM ¼ 0:03ðS:D: ¼ 0:18Þ to Time 2 ðM ¼ 0:0ðS:D: ¼ 0:0Þ, z ¼ �1:73; p ¼ 0:08Þ.

DISCUSSION

This study examined absolute and comparativeperceived cancer risk at two key time points in thegenetic testing process: 1–2 days after counselingand 1 week after receipt of test results. In addition,we investigated the common sense model as a wayto organize and understand reasons for riskperceptions in individuals testing for mutationsin the BRCA1 and BRCA2 genes.

We hypothesized that individuals testing posi-tive would report increased absolute and com-

parative perceived cancer risk, and individualstesting negative will report decreased absolute andcomparative perceived cancer risk. In the analysisfor absolute perceived risk, only a trend emergedfor an interaction of time � test result � cancerhistory such that individuals with a personalcancer history testing negative decreased in abso-lute perceived risk from post-counseling to post-result. In the analysis of comparative perceivedrisk, an interaction of change from post-counsel-ing to post-results by test result emerged such thatthose testing negative decreased in comparativeperceived risk. Hence, our first hypothesis receivedonly partial support: those testing negative de-creased in risk while those testing positive did notchange. It appears that individuals may beassuming that they have a hereditary mutation

Table 4. Reasons for comparative perceived breast cancer risk

Item Time 1 #

reporting

Time 2 #

reporting

Greater than general population (Time 1: N=73; Time 2: N=62)



Gene status (Have or will be found to have a BRCA1/2 mutation) 5 (7%) 16 (26%)

Gene Status (Do not have a mutation) 2 (3%)

Gene Status (Have another mutation) 1 (2%)

Environment 1 (1%)

Type of previous cancer 7 (10%) 6 (10%)

Diet or exercise 3 (5%)

Diagnosed prior to 50/menopause (e.g. My cancer was diagnosed before menopause, so my

chances are greater)

3 (4%)

Getting older 1 (1%)

Luck 2 (3%)

Ethnicity: Ashkenazi Jewish 4 (6%) 2 (3%)

Same as general population (Time 1: N=9; Time 2: N=21)



Gene status (Have a mutation) 1 (5%)

Gene status (Do not have or will not be found to have a mutation) 1 (11%) 12 (57%)

Environment 1 (11%)


Diet or exercise (e.g. I eat a healthy diet) 2 (22%) 2 (10%)

Young age 1 (11%)

Statistics (e.g. The statistics are positive) 1 (11%)

Lower than general population (Time 1: N=11; Time 2: N=9)


Gene status (Do not have or will not be found to have a mutation) 2 (22%)


Surgery, drugs, or radiation (e.g. I’ve had tamoxifen) 11 (100%) 7 (78%)

Diet or exercise 3 (27%)

Optimism 1 (9%)



until receiving test results to the contrary; this maybe a coping method of ‘assuming the worst’ tomanage anxiety, consistent with the concept ofdefensive pessimism (Norem and Cantor, 1986).

Important to note, a number (Time 1: 7; Time 2:12) of individuals had difficulty in giving a ‘yes’ or‘no’ response for the absolute perceived riskmeasure. Rather than finding this a limitation ofthe crudeness of our measure, we believe this hasimportant implications for cancer control. Mostindividuals were readily able to report whether ornot they felt they would develop cancer. Mostreported that they believed they would developcancer. However, despite their increased risk, 30individuals at pre-counseling and post-counselingdid not believe that they would ever developcancer, and 14 of these individuals did not changefrom post-counseling to post-result. We wouldsuggest that individuals who believe that they willnot get cancer, especially those who did not changeafter receiving a test result, would have littlemotivation, rationally, to engage in behaviors toprevent or screen for cancer.

Our second hypothesis was that no personalcancer history and a negative test result would beassociated with lower absolute and comparativeperceived risk. This hypothesis was not supported.Those with no personal history of cancer did notdiffer from those with a personal cancer history,and those with no personal history did not changein perceptions of risk. That those with no personalhistory receiving informative negative results didnot lower their absolute or comparative risk ofcancer and that their risk was as high as those whopreviously had cancer is particular concern.Although they are not at objectively increased riskfor cancer, individuals with no personal cancerhistory receiving informative negative results maybe driven to engage in health behaviors such asprophylactic surgery. We believe unrealistic pessi-mism}a pessimistic bias in the appraisal of risk, asopposed to unrealistic optimism (Weinstein,1984)}an optimistic bias in the appraisal of risk,may be a driving factor.

Although not consistent with our hypothesis, atrend was observed for decreased comparativeperceived risk for those with a personal history ofcancer receiving uninformative negative results.Objectively, in our study, individuals with apersonal history of cancer remain at a higher levelof risk than those with no personal history ofcancer because (1) individuals with no personalhistory of cancer have at most a 50% chance of

inheriting a mutation while those with a personalhistory could theoretically have a 100% chancehaving a hereditary mutation, and (2) results aremore likely to be informative for those with nopersonal history of cancer. Individuals with apersonal cancer history receiving uninformativenegative results remain at higher risk than thosewithout a personal history as they may have adifferent BRCA1/2 mutation than those tested inthis study, some other hereditary mutation, orsome environmental pre-disposing factor thatprecipitated the initial development of cancer.Thus, the finding that those with a personalhistory of cancer had decreased perceived riskmay be of concern as the reason for their initialcancer is unknown.

Qualitative data analysis revealed a number ofreasons for absolute and comparative perceivedcancer risk. Common reasons for believing thatthey would not develop cancer (again) (Absoluteperceived risk) or that risk was lower than thegeneral population (Comparative perceived risk)included having no mutation, optimism, andpreventive surgery. Common reasons for believingthat they would develop cancer (again) (Absoluteperceived risk) or that risk was higher than thegeneral population (Comparative perceived risk)included having a personal and/or family historyof cancer and having an inherited mutation. Thus,although gene status and cancer history did notseem to have a great impact in the quantitativeassessment of risk, gene status and cancer historywere commonly cited reasons in the qualitativeassessment of risk.

Few people mentioned risk estimates given incounseling as reasons for risk. We have threepotential explanations of this finding: (1) riskestimates given in counseling were implicit in theirresponses, (2) individuals in the study may nothave given attention to risk information presentedin counseling, or (3) probability does not weighheavily in the perception of risk. The latter twopotential explanations merit further investigation.Underlying these latter two potential explanationscould be issues of numeracy: the ability to receiveand interpret numeric data (Woloshin et al., 2001).Indeed, processing numeric data has been shownto be a challenge even for highly educatedindividuals, such as medical students (Sheridanand Pignone, 2002). Thus, individuals with lowernumeracy may give little attention to informationwhich they do not understand, or even if they dopay attention, lower numeracy may limit the

K. KELLY ET AL.44


ability of an individual to use numeric, probabilityinformation to make necessary health decisions.Rather than rely on difficult to comprehendprobability information, they may rely on otherlife experiences to determine their levels of risk.

The common sense model was helpful inconceptualizing the reasons for perceived risk.Causes due to heredity (gene status) and environ-ment were commonly cited. Control or curemethods were also considered in perceived risksuch as surgeries (mastectomy) and drugs tocontrol risk (tamoxifen). Timeline was mentionedon occasion, and we believe that using timelineinformation (e.g. presenting the consultand’s riskof developing cancer at a particular age, such asthe age at which a parent developed cancer) in thepresentation of risk information may be helpful.Future studies may elucidate the role of timeline inthe presentation of risk information. Finally,statements mentioning probability, statistics, orluck were more difficult to classify. These state-ments were coded as label, but it may bequestionable the degree to which a probabilityshould be Label. Further, ‘luck’ which wasconsidered a part of label may reflect fatalismrather than the cognitive representation of risk.We did not find evidence of consequences (e.g.insurance discrimination) in reasons for risk.

A number of other reasons could not beconceptualized in terms of the common sensemodel. However, the larger self-regulation theory(Leventhal et al., 1992, 1997) may be helpful inunderstanding risk. The self-regulation theoryposits that parallel and interacting cognitive andaffective processes guide the mental representationof a health threat, the procedures one undergoes tomanage a health threat, and the appraisal of one’sability to manage the health threat. These pro-cesses occur within the self-system (backgroundfactors such as age and disposition) and areinfluenced by surrounding social and culturalfactors. Mentioned self-system factors includedgender and ethnicity (e.g. Ashkenazi Jewish).Individuals of Ashkenazi Jewish descent are atincreased risk of breast cancer and have a higherfrequency of mutations in BRCA1/2 genes.Further, affective factors (e.g. optimistic strategy)were noted as reasons for risk perception. Difficultto interpret is how ‘knowing others who have hadcancer’ (a social factor) plays a role in risk, exceptthat this could be used as an availability heuristic(Tversky and Kahneman, 1974). In the case of anavailability heuristic, the greater the number of

individuals one knows with cancer would beassociated with increased perception of risk forthe self. Hence, we believe factors from the largerself-regulation theory, in addition to the commonsense model, may be helpful in understanding howan individual estimates his/her risk of cancer.However, the current study found the mostsupport for the cognitive mental representation(i.e. common sense model) as explaining one’s risk.

For the most part, the frequency of mention ofcommon sense model attributes did not change.For absolute perceived risk, change was onlyevidenced in causes such that causes were morefrequently mentioned at post-counseling than atpost-result. For comparative perceived risk, atrend for change emerged such that timeline andlabels were mentioned more frequently at post-counseling than at post-result. Hence, the reasonsmentioned for risk showed little change, and this isconsistent with the finding that genetic test resultshad little influence on levels of absolute andcomparative perceived risk. Thus, based on thesedata, one might conclude that perceived risk andreasons underlying perceived risk are highlyresistant to change. Genetic testing may have littleimpact on risk perceptions. Individuals may not bemotivated to engage in appropriate health beha-viors and screening based on accurate perceptionsof risk.

Limitations

Since a number of families participated in thestudy, discussion within families may have con-taminated the data; although, this contaminationshould be random among those with differinglevels of education and with differing cancerhistories. Power was also of concern as there wereno individuals with a personal history of cancerreceiving informative negative results. Further, thesample was of relatively high socio-economicstatus, and this may affect the generalizability ofour findings. Also, our absolute and comparativerisk questions were not directly comparable in thatour absolute risk question asked for lifetime cancer(generic) risk and our comparative risk questionasked for lifetime breast cancer risk. It is possiblethat individuals may have confused general andspecific risks when answering these questions. Inaddition, because we did not have audio cassetterecordings of the phone interviews, we can onlyoffer a few examples of the responses we heard in



our interviews (See Tables 2 and 4). Finally, we didnot provide personalized estimates of risk forindividuals in the initial counseling session nor didwe provide personalized percentage risk estimatesfor individuals receiving uninformative negativeresults. It is possible that greater change inperceived risk might have been noted based onpersonalized risk estimates.

SUMMARY/IMPLICATIONS

In sum, predicting health behavior based onperceived risk and changing risk perceptions tomodify health behavior have been elusive. Indivi-duals in the genetic counseling context have been

found to have inappropriate levels of perceivedrisk and health behaviors in relation to theirempirical level of risk. In this paper, we haveendeavored to elucidate some of the factorsindividuals consider when making estimates abouttheir levels of risk, using the common sense modeland the larger self-regulation theory to guide ourunderstanding. We have also shown that estimatesof perceived risk are rather resistant to change andmay not be based on rational, empirical factors.The common sense model may be useful inunderstanding reasons for perceptions of riskand provide an heuristic for educational andcounseling efforts. To conclude, understandingthe way individuals form risk estimates will becritical to designing interventions that will encou-rage appropriate health behaviors.

Table 5. Common sense model classifications of comparative perceived breast cancer risk

Item Time 1 #

reporting

Time 2 #

reporting

Greater than general population

Causes: 82 80

(family history, personal history, having an inherited mutation, type of previous cancer,

environment, other biological risk factors)

Control or cure: 3

(diet, exercise)

Timeline: 4

(getting older, diagnosed before 50/menopause)

Label: 2

(luck)

Not classified:

Ethnicity: Ashkenazi Jewish 4 2

Same as general population

Causes: 5 16

(family history, personal history, no inherited mutation, type of previous cancer,

environment)


(diet, exercise)

Timeline: 1

(young age)

Label: 1

(statistics)

Lower than general population

Causes: 6 6

(personal history, no inherited mutation, type of previous cancer)


(surgery, drug treatments, diet, exercise)

Not classified:

Psychological/ emotional (Optimism) 1

K. KELLY ET AL.46


ACKNOWLEDGEMENTS

This study was supported by grants from the New JerseyCommission on Cancer Research and the Mid-AtlanticRegional Human Genetics Network.

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