mary-care setting: factors associated with the acceptance and completion of ... Jette AM, Cummings KM, Brock BM et al: The structure. 1342. CAN MED ASSOC J * ler MAI ... NASPE, Natick Executive Park, 2 Vision Dr.,. Natick MA 01760-2059; ...
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FACTORS DETERMINING COMPLIANCE WITH SCREENING MAMMOGRAPHY Marie-Dominique Beaulieu, MD, CCFP, MSc; Frangois Beland, PhD; Denis Roy, MD, MPH, MSc, FRCPC; Maurice Falardeau, MD, FRCPC; Guy Hebert, MD, FRCPC
Objective: To determine factors affecting compliance with screening mammography prescribed by family physicians. Design: Secondary analysis of a nonrandomized trial. Setting: University-affiliated family medicine clinic in Montreal. Patients: Women aged 50 to 69 years who were given a written prescription for a screening mammography during their visit at the clinic between Oct. 12, 1991, and May 31, 1992, and who had not undergone mammography in the preceding 2 years and had never been treated for breast cancer. Information on the potential factors was obtained through a telephone questionnaire 2 months after the visit. Outcome measures: Indicator of compliance: presence of result of screening mammography in patient chart; potential factors influencing compliance: age, level of education, marital status, socioeconomic level, smoking status, perceived health status, perceived psychological well-being, risk factors for breast cancer, use of health services including frequency of Papanicolaou test, Health Belief Model variables. Results: Of the 171 eligible women 113 (66.1%) underwent the prescribed mammography within 2 months after the visit to the clinic, and 149 (87.1 %) responded to the questionnaire. The patients' socioeconomic characteristics, perceived health status, health utilization indices and risk factors for breast cancer were not found to be predictors of compliance. The strongest predictor of compliance was the number of previous mammograms. Women who had undergone mammography previously were less likely to be noncompliant than those who had not (odds ratio [OR] 0.1 1, 95% confidence interval [Cl] 0.02 to 0.51; p = 0.005). Women who did not comply were less likely than those who did to believe that a prescription from their physician would convince them to undergo mammography (OR 0.21, 95% Cl 0.07 to 0.60; p 0.004). Other factors associated with noncompliance were the expression of fear of mammography (OR 2.09, 95% Cl 1.08 to 4.02; p = 0.03) and the lack of time to take the test (OR 3.07, 95% Cl 1.21 to 7.80; p = 0.02). Being a smoker was negatively associated with compliance (OR 0.43, 95% Cl 0.22 to 0.86; p = 0.02). The stepwise logistic regression model accounted for 87.5% of the outcome (X2 for goodness of fit = 164.4; p = 0.0001). Conclusion: Family physicians who prescribe screening mammography, even to women who consult for other reasons, are likely to overcome some of the barriers observed in association with population screening rates. However, physician-oriented approaches are not likely to reach the 30% to 40% of reluctant women who appear to hold negative views toward physicians' recommendations. Further study is necessary to determine how better to reach these women. =
Objectif: Determiner les facteurs qui jouent sur lobservation depistage etablies par des medecins de famille. Conception Analyse secondaire d'une etude non randomisee.
des ordonnances de mammographie de
Dr. Beaulieu is associate professor in the Department of Family Medicine, Family Medicine Unit, Hopital Notre-Dame and Groupe de recherche interdisciplinaire en sante, Universitd de Montreal, Montreal, Que.; Dr. 86/and is professor in the Departement of Health Administration and Groupe de recherche interdisciplinaire en sante, Universitd de Montrdal; Dr. Roy is clinical assistant professor in the Department of Family Medicine, Universite de Montrdal, and director of planning, Direction de la santd publique, Rdgie rdgionale de Montrdal; Dr. Falardeau is professor in the Department of Surgery, Universite de Montreal; and Dr. Hdbert is professor in the Department of Radiology, Hopital Notre-Dame, and Faculty of Medicine, Universitd de Montrdal.
Reprint requests to: Dr. Marie-Dominique Beaulieu, Family Medicine Clinic, 2025, rue Plessis, Montreal QC
H2L 2Y4
1996 Canadian MedicalAssociation (text and abstract/rdsumd)
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Contexte Clinique de medecine familiale affiliee a une universite de Montreal. Patientes Femmes de 50 'a 69 ans auxquelles on a prescrit une mammographie de depistage au cours de leur visite 'a la clinique, entre le 12 oct. 1991 et le 31 mai 1992, qui n'avaient pas subi de mammographie au cours des 2 annees precedentes et qui n'avaient jamais et traitees pour un cancer du sein. On a obtenu des renseignements sur les facteurs possibles 'a laide d'un questionnaire telephonique 2 mois apres la consultation. Mesures des resultats: Indicateur de conformite presence du resultat d'une mammographie de depistage dans le dossier de la patiente; facteurs pouvant agir sur la conformite: age, niveau d'instruction, etat civil, classe socio-economique, tabagisme, etat de sante percu, bien-etre psychologique percu, facteurs de risque 'a lF6gard du cancer du sein, utilisation de services de sante, y compris frequence du test de Papanicolaou, variables du modele de croyance a la sante. Resultats Sur les 171 femmes admissibles, 113 (66,1 %) ont subi la mammographie prescrite dans les 2 mois suivant la consultation a la clinique, et 149 (87,1 %) ont repondu au questionnaire. Les caracteristiques socio-economiques des patientes, leur etat de sante percu, les indices d'utilisation des services de sante et les facteurs de risque 'a l'gard du cancer du sein n'ont pas agi comme predicteurs de la conformite. Le predicteur le plus solide de la conformite est le nombre de mammographies anterieures. Les femmes qui avaient deja subi une mammographie etaient moins susceptibles de ne pas se conformer que celles qui n'en n'avaient pas subi (ratio des probabilites [RP] 0,1 1, intervalle de confiance [IC] a 95 %, 0,02 a 0,5 1; p = 0,005). Les femmes qui ne se sont pas conformees 'a lordonnance etaient moins susceptibles que celles qui s'y sont conformees de croire qu'une ordonnance de leur medecin les convaincrait de subir une mammographie (RP 0,21, IC a 95 %, 0,07 a 0,60; p = 0,004). D'autres facteurs ont et associes 'a a non-conformite: la peur exprimee face a la mammographie (RP 2,09, IC a 95 %, 1,08 a 4,02; p = 0,03) et le manque de temps pour subir le test (RP 3,07, IC a 95 %, 1,21 a 7,80; p = 0,02). On a etabli un lien defavorable entre le tabagisme et la conformite (RP 0,43, IC a 95 %, 0,22 a 0,86; p = 0,02). Le modele d'analyse de regression logistique par etapes a explique 87,5 % du resultat (X2 pour la validite de lajustement = 164,4; p = 0,0001). Conclusion Les medecins de famille qui prescrivent des mammographies de depistage, meme aux femmes qui les consultent pour d'autres raisons, ont des chances de surmonter certains des obstacles observes 'a l'gard des taux de depistage dans la population. 11 est cependant peu probable que les demarches axees sur les medecins r-ussissent a atteindre les 30 % a 40 % de femmes hesitantes qui semblent avoir une opinion negative des recommandations des medecins. Une etude plus poussee s'impose si Ion veut trouver un moyen de mieux atteindre ces femmes.
A mammography screening program can be expected to reduce the rate of death from breast cancer by about 40% among women 50 to 69 years old if it succeeds in reaching 65% to 90% of the eligible population regularly.' Although screening rates have been steadily increasing, surveys conducted in Canada and the United States suggest that up to 50% of eligible women are not screened2-, and that population-based screening programs are not successful in reaching equally all groups of women at risk (i.e., women over 60 years of age and those living in lower socioeconomic areas)."' Many population surveys on the factors associated with either the intent to undergo mammography or past mammography experience have been published. Some constants have been observed: age over 60 years and poverty are associated with low screening rates,5 2-14 and knowledge of risk factors for breast cancer and of recommendations to undergo mammography does not appear to increase compliance consistently.56 Investigators who have included Health Belief Model (HBM) variables in their analyses suggest that perceived susceptibility to breast cancer and perceived barriers to mammography are the principal operative HBM variables.'5-'9 Some have suggested that women who perceive themselves as 1336
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being unhealthy are less likely to undergo screening mammography.1'4 Of all the factors associated with exposure to screening mammography, a recommendation by a physician appears to be the strongest stimulus to action.561215 1720 Hence, family physicians can play an important role in improving womens participation in screening programs. However, studies of the effectiveness of interventions by family physicians have shown that up to 40% of the targeted women did not follow their physician's advice.'322-26 Unfortunately, none of these studies controlled for the factors known to affect mammography rates, giving no insight into the characteristics of the women who declined their physician's recommendation. Only one of these studies was conducted in Canada.25 Between October 1991 and June 1992 we conducted a nonrandomized controlled trial at two family medicine clinics in Montreal to evaluate the effectiveness of an opportunistic approach to screening with mammography.27 All eligible women visiting the "experimental" clinic were systematically given a written prescription for a mammography by the family physician, regardless of the reason for the visit. A computer-generated reminder to prescribe mammography was placed on the
woman's chart before the visit. There was no intervention to modify the regular process of care at the "control" clinic, where physicians reported prescribing mammography mostly during visits related to health maintenance. At the end of the study period the odds ratio (OR) for having undergone mammography in the entire study population was 14.11 (95% confidence interval [Cl] 7.85 to 28.58) among the women at the experimental clinic.27 The effect of the intervention was so strong that none of the other explanatory factors considered was associated with the probability of undergoing mammography during the study period. However, 33.6% of the women at the experimental clinic did not comply with the physician's prescription, a figure comparable to that reported in other studies.'3'2'-26 Since we had already collected the information in the first study, we decided to perform a secondary analysis involving only the women at the experimental clinic to determine which factors were associated with the likelihood of undergoing screening mammography. We hypothesized that socioeconomic variables, health status, previous use of health services, risk factors for breast cancer and HBM variables could be independent factors affecting compliance with the prescribed mammography.
problem already reducing life expectancy, such as an active cancer). Women who visited the clinic again during the study period were not included. INTERVENTION
During the visit the physician gave a written prescription for a mammogram, regardless of the reason for the encounter, along with general counselling about the method of screening. We met with the physicians before the study began in order to discuss its objective. They agreed that reaching all eligible women for breast cancer screening was an important practice goal and that discussing and offering screening mammography during any kind of encounter was acceptable. It was not mandatory to perform a clinical breast examination at the moment. A computer-generated reminder flow-sheet was placed on the chart of each woman before the visit. Throughout the study, physicians were kept up to date on the number of subjects they included. The women were asked to make an appointment for the mammogram at the radiology facilities of the hospital within a month of the visit. We later examined the charts to see whether the result of the mammogram was present.
QUESTION NAI RE
METHODS The complete study protocol has been described previously.27 This article reports only the data from the experimental clinic and is limited to the women who were given a written prescription for mammography. The experimental clinic was a university-affiliated family medicine clinic in Montreal that served mainly a low socioeconomic, white, French-speaking population. The clinic had 13 general practitioners paid on a fee-forservice basis and 11 family medicine residents. Only 20% of the patients were followed by the residents, who acted as the attending physician under supervision. The family medicine clinic was reported as the only source of primary care during the 6 months preceding the study period by 75% of the subjects. PATIENT POPULATION
We targeted women 50 to 69 years of age who visited the clinic with or without an appointment between Oct. 12, 1991, and May 31, 1992. Women were excluded if they reported having had a mammogram within the preceding 2 years or had been treated for breast cancer. Women were also excluded if the physician felt that their medical condition was a contraindication to screening mammography (e.g., any acute unstable medical or psychiatric condition or the presence of a major health
All the study variables except the reason for the visit to the clinic were obtained from the women during a telephone interview with a registered nurse 2 months after the visit; the reason for the visit was written on the flow sheet by the physician. The International Classification of Primary Care28 was used to code the reasons for the encounter. We waited 2 months before interviewing patients because we wanted to avoid having the interview influence the subjects' decision to undergo mammography. If a woman could not be reached after three attempts, she was considered a nonrespondent. Five categories of independent variables known to be associated with mammography rates were considered. * Sociodemographic characteristics: age, level of education, marital status, and economic status (poor or not poor) according to income level and number of dependants, as it pertains to the city of Montreal.29 * Health status and psychological well-being: the subjects' perceived health status was measured with the use of a validated French translation of the self-rated perceived health status scale.30 Subjects were asked to qualify their perception of their state of health and to compare it with that of people their age on a 5-point Likert scale. Its reliability has been well established,3 and it has been used in Quebec health surveys4'32 and by Fink and Shapiro"' in their study of the factors associated with responding to an invitaCAN MED ASSOC J * MAY 1, 1996; 154 (9)
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tion to be screened. We used the Affect-Balance Scale,, to measure psychological well-being. It consists of 10 questions and has been properly validated.34 Other health-related variables measured were previous breast disease, hysterectomy, hormonal replacement therapy and smoking status. * Risk factors for breast cancer: age at menarche and menopause, age at first pregnancy, parity and family history of breast cancer were measured using questions from the Quebec health survey.4 * Previous use of preventive and primary care services: use of other primary care resources and gynecological services, appropriateness of Papanicolaou testing schedule, number of visits at the clinic in the previous 6 months and previous use of mammography. * Beliefs and attitudes: subjects' beliefs and attitudes toward breast cancer in general and screening in particular were measured using the HBM and questions to evaluate their knowledge of screening recommendations and their perception of what women their age actually do. At the planning stage of the study no properly validated HBM questionnaire in relation to screening mammography was available. On the basis of previously published questionnaires35-39 we constructed scales measuring the following HBM variables: perceived personal risk of breast cancer, perceived severity of breast cancer, effectiveness of screening and treatments, perceived barriers to screening and treatments, perceived efficiency in performing breast self-examination, knowledge of recommendations for screening mammography and perception of the social norm concerning breast cancer screening. Since the telephone interview was held after the intervention, questions about potential barriers to screening asked for reasons why the woman would refuse to undergo another mammogram if she had already had one. To validate the HBM scales and to pretest the questionnaire as a whole, the questionnaire was first administered to a pilot group of 10 women, who were asked for feedback on the relevance and clarity of the questions. A revised questionnaire was administered to another 45 women. Exploratory and confirmatory factor analyses were performed and HBM scales constructed from this questionnaire with the use of the SPSS/PC+ 4.0 statistical package (Advanced Statistics 4.0 version, SPSS Inc., Chicago, 1990). The factorial analysis confirmed the hypothesized dimensions of the HBM scales. The final HBM variables were perceived risk of breast cancer, perceived severity of breast cancer, perceived barriers to treatments, fear-related barriers to mammography, timerelated barriers to mammography, perceived efficiency in performing breast self-examination and perceived effectiveness of treatments. 1338
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STATISTICAL ANALYSIS To study the effect of the variables on compliance with mammography we performed stepwise logistic regression analysis using the SPSS/PC+ statistical package. Variables were entered in the following order: sociodemographic variables, health status variables, risk factors for breast cancer, HBM variables, utilization variables and number of previous mammograms. As suggested by Hosmer and Lemeshow40 two conditions determined the inclusion of variables in each step. First, variable pairs with correlation coefficients of more than 0.4 were examined; one of the variables was excluded to avoid colinearity. Second, all variables that were found to be statistically significant at the 0.1 level in step one were reintroduced in later steps to avoid missing potentially significant variables.
RESULTS Of the 392 women who visited the clinic during the study period 192 were considered eligible for a screening mammogram. Of the 200 women who were excluded 158 had undergone mammography in the previous 2 years, 21 had medical contraindications, 13 had been treated for breast cancer, and 8 had a language barrier. Compliance with the study protocol was identical for the resident and staff physicians. Physicians,forgot to prescribe mammography for 21 (10.9%) of the 192 eligible women, for a final study sample of 171 women. Of the 171 women 1 13 (66.1 %) underwent the prescribed mammography within 2 months after the visit to the clinic. The difference in the distribution of reasons for the visit between the women who did and those who did not undergo mammography was not statistically significant, although the proportion of women who visited the clinic for a medical problem not related to a gynecological reason or a health check-up was greater in the noncompliant group (69.5% v. 86.4%; p = 0. 13). The overall response rate to the telephone questionnaire was 87.1% (149/171). Nine women, five of whom were in the noncompliant group, refused to answer the questions. Thirteen women, nine of whom were in the noncompliant group, could not be reached. Thus, the response rate was 92.9% in the compliant group and 75.9% in the noncompliant group (p = 0.02). The respondents and nonrespondents who did or did not comply with the prescribed mammography were comparable in terms of age and type of visit (with or without an appointment); however, slightly more nonrespondents than respondents in the compliant group visited the clinic for reasons other than health check-up or gynecological problems (Table 1). The distribution of the principal sociodemographic and medical characteristics of the respondents according
to mammography status are shown in Table 2. There was no significant difference in any of the variables between the compliant and noncompliant groups. The results of the final logistic regression model appear in Table 3. The model predicts noncompliance. It accounted for 87.5% of the outcome (%2 for goodness of
fit = 164.4; p = 0.0001). None of the sociodemographic variables affected the compliance rate. Smoking was the only health status variable associated with the outcome, in all steps of the analysis. Neither the overall score for breast cancer risk factors nor a family history of breast cancer was related to compliance.
wa notunoergo -mammography-
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Variable Mean age, yr No. (and %) of women who visited the clinic with an appointment Reason for visit, no. (and %) of women Hdalth check-up
Nonrespordents np8pvalue
Respondents n 105
Specifi.c medical. problem*. Gynecological problem *Other than gynecological problern.
Respondents
Nonrespondents n=14 58.8
pvalue 0.79
60.8
63.9
0.34
n= 44 59.6
74 (70.5)
3 (37.5)
0.16
27 (61.4)
6 (42.9)
0.33
21(20.0) 73 (69.5) 11(10.5)
2 (25.0) 6 (75.0) 0
0.62
5 (11.4) .38 (86.4) 1 (2.3)
2 (14.3) 12(85.7)
0.82
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0.39
24 (54.5)
48 (45.7) .,~tL~
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