Efficacy of a simple, low-cost educational intervention in improving knowledge about risks and benefits of screening mammography

Patient preferences for breast cancer screening: a systematic review update to inform recommendations by the Canadian Task Force on Preventive Health Care

BACKGROUND

Different guideline panels, and individuals, may make different decisions based in part on their preferences. Preferences for or against an intervention are viewed as a consequence of the relative importance people place on the expected or experienced health outcomes it incurs. These findings can then be considered as patient input when balancing effect estimates on benefits and harms reported by empirical evidence on the clinical effectiveness of screening programs. This systematic review update examined the relative importance placed by patients on the potential benefits and harms of mammography-based breast cancer screening to inform an update to the 2018 Canadian Task Force on Preventive Health Care's guideline on screening.

METHODS

We screened all articles from our previous review (search December 2017) and updated our searches to June 19, 2023 in MEDLINE, PsycINFO, and CINAHL. We also screened grey literature, submissions by stakeholders, and reference lists. The target population was cisgender women and other adults assigned female at birth (including transgender men and nonbinary persons) aged ≥ 35 years and at average or moderately increased risk for breast cancer. Studies of patients with breast cancer were eligible for health-state utility data for relevant outcomes. We sought three types of data, directly through (i) disutilities of screening and curative treatment health states (measuring the impact of the outcome on one's health-related quality of life; utilities measured on a scale of 0 [death] to 1 [perfect health]), and (ii) other preference-based data, such as outcome trade-offs, and indirectly through (iii) the relative importance of benefits versus harms inferred from attitudes, intentions, and behaviors towards screening among patients provided with estimates of the magnitudes of benefit(s) and harms(s). For screening, we used machine learning as one of the reviewers after at least 50% of studies had been reviewed in duplicate by humans; full-text selection used independent review by two humans. Data extraction and risk of bias assessments used a single reviewer with verification. Our main analysis for utilities used data from utility-based health-related quality of life tools (e.g., EQ-5D) in patients; a disutility value of about 0.04 can be considered a minimally important value for the Canadian public. When suitable, we pooled utilities and explored heterogeneity. Disutilities were calculated for screening health states and between different treatment states. Non-utility data were grouped into categories, based on outcomes compared (e.g. for trade-off data), participant age, and our judgements of the net benefit of screening portrayed by the studies. Thereafter, we compared and contrasted findings while considering sample sizes, risk of bias, subgroup findings and data on knowledge scores, and created summary statements for each data set. Certainty assessments followed GRADE guidance for patient preferences and used consensus among at least two reviewers.

FINDINGS

Eighty-two studies (38 on utilities) were included. The estimated disutilities were 0.07 for a positive screening result (moderate certainty), 0.03-0.04 for a false positive (FP; "additional testing" resolved as negative for cancer) (low certainty), and 0.08 for untreated screen-detected cancer (moderate certainty) or (low certainty) an interval cancer. At ≤12 months, disutilities of mastectomy (vs. breast-conserving therapy), chemotherapy (vs. none) (low certainty), and radiation therapy (vs. none) (moderate certainty) were 0.02-0.03, 0.02-0.04, and little-to-none, respectively, though in each case findings were somewhat limited in their applicability. Over the longer term, there was moderate certainty for little-to-no disutility from mastectomy versus breast-conserving surgery/lumpectomy with radiation and from radiation. There was moderate certainty that a majority (>50%) and possibly a large majority (>75%) of women probably accept up to six cases of overdiagnosis to prevent one breast-cancer death; there was some uncertainty because of an indication that overdiagnosis was not fully understood by participants in some cases. Low certainty evidence suggested that a large majority may accept that screening may reduce breast-cancer but not all-cause mortality, at least when presented with relatively high rates of breast-cancer mortality reductions (n = 2; 2 and 5 fewer per 1000 screened), and at least a majority accept that to prevent one breast-cancer death at least a few hundred patients will receive a FP result and 10-15 will have a FP resolved through biopsy. An upper limit for an acceptable number of FPs was not evaluated. When using data from studies assessing attitudes, intentions, and screening behaviors, across all age groups but most evident for women in their 40s, preferences reduced as the net benefit presented by study authors decreased in magnitude. In a relatively low net-benefit scenario, a majority of patients in their 40s may not weigh the benefits as greater than the harms from screening whereas for women in their 50s a large majority may prefer screening (low certainty evidence for both ages). There was moderate certainty that a large majority of women 50 years of age and 50 to 69 years of age, who have usually experienced screening, weigh the benefits as greater than the harms from screening in a high net-benefit scenario. A large majority of patients aged 70-71 years who have recently screened probably think the benefits outweigh the harms of continuing to screen. A majority of women in their mid-70s to early 80s may prefer to continue screening.

CONCLUSIONS

Evidence across a range of data sources on how informed patients value the potential outcomes from breast-cancer screening will be useful during decision-making for recommendations. The evidence suggests that all of the outcomes examined have importance to women of any age, that there is at least some and possibly substantial (among those in their 40s) variability across and within age groups about the acceptable magnitude of effects across outcomes, and that provision of easily understandable information on the likelihood of the outcomes may be necessary to enable informed decision making. Although studies came from a wide range of countries, there were limited data from Canada and about whether findings applied well across an ethnographically and socioeconomically diverse population.

SYSTEMATIC REVIEW REGISTRATION

Protocol available at Open Science Framework https://osf.io/xngsu/ .

Shared decision-making for supporting women's decisions about breast cancer screening

BACKGROUND

In breast cancer screening programmes, women may have discussions with a healthcare provider to help them decide whether or not they wish to join the breast cancer screening programme. This process is called shared decision-making (SDM) and involves discussions and decisions based on the evidence and the person's values and preferences. SDM is becoming a recommended approach in clinical guidelines, extending beyond decision aids. However, the overall effect of SDM in women deciding to participate in breast cancer screening remains uncertain.

OBJECTIVES

To assess the effect of SDM on women's satisfaction, confidence, and knowledge when deciding whether to participate in breast cancer screening.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group's Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform on 8 August 2023. We also screened abstracts from two relevant conferences from 2020 to 2023.

SELECTION CRITERIA

We included parallel randomised controlled trials (RCTs) and cluster-RCTs assessing interventions targeting various components of SDM. The focus was on supporting women aged 40 to 75 at average or above-average risk of breast cancer in their decision to participate in breast cancer screening.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and conducted data extraction, risk of bias assessment, and GRADE assessment of the certainty of the evidence. Review outcomes included satisfaction with the decision-making process, confidence in the decision made, knowledge of all options, adherence to the chosen option, women's involvement in SDM, woman-clinician communication, and mental health.

MAIN RESULTS

We identified 19 studies with 64,215 randomised women, mostly with an average to moderate risk of breast cancer. Two studies covered all aspects of SDM; six examined shortened forms of SDM involving communication on risks and personal values; and 11 focused on enhanced communication of risk without other SDM aspects. SDM involving all components compared to control The two eligible studies did not assess satisfaction with the SDM process or confidence in the decision. Based on a single study, SDM showed uncertain effects on participant knowledge regarding the age to start screening (risk ratio (RR) 1.18, 95% confidence interval (CI) 0.61 to 2.28; 133 women; very low certainty evidence) and frequency of testing (RR 0.84, 95% CI 0.68 to 1.04; 133 women; very low certainty evidence). Other review outcomes were not measured. Abbreviated forms of SDM with clarification of values and preferences compared to control Of the six included studies, none evaluated satisfaction with the SDM process. These interventions may reduce conflict in the decision made, based on two measures, Decisional Conflict Scale scores (mean difference (MD) -1.60, 95% CI -4.21 to 0.87; conflict scale from 0 to 100; 4 studies; 1714 women; very low certainty evidence) and the proportion of women with residual conflict compared to control at one to three months' follow-up (rate of women with a conflicted decision, RR 0.75, 95% CI 0.56 to 0.99; 1 study; 1001 women, very low certainty evidence). Knowledge of all options was assessed through knowledge scores and informed choice. The effect of SDM may enhance knowledge (MDs ranged from 0.47 to 1.44 higher scores on a scale from 0 to 10; 5 studies; 2114 women; low certainty evidence) and may lead to higher rates of informed choice (RR 1.24, 95% CI 0.95 to 1.63; 4 studies; 2449 women; low certainty evidence) compared to control at one to three months' follow-up. These interventions may result in little to no difference in anxiety (MD 0.54, 95% -0.96 to 2.14; scale from 20 to 80; 2 studies; 749 women; low certainty evidence) and the number of women with worries about cancer compared to control at four to six weeks' follow-up (RR 0.88, 95% CI 0.73 to 1.06; 1 study, 639 women; low certainty evidence). Other review outcomes were not measured. Enhanced communication about risks without other SDM aspects compared to control Of 11 studies, three did not report relevant outcomes for this review, and none assessed satisfaction with the SDM process. Confidence in the decision made was measured by decisional conflict and anticipated regret of participating in screening or not. These interventions, without addressing values and preferences, may result in lower confidence in the decision compared to regular communication strategies at two weeks' follow-up (MD 2.89, 95% CI -2.35 to 8.14; Decisional Conflict Scale from 0 to 100; 2 studies; 1191 women; low certainty evidence). They may result in higher anticipated regret if participating in screening (MD 0.28, 95% CI 0.15 to 0.41) and lower anticipated regret if not participating in screening (MD -0.28, 95% CI -0.42 to -0.14). These interventions increase knowledge (MD 1.14, 95% CI 0.61 to 1.62; scale from 0 to 10; 4 studies; 2510 women; high certainty evidence), while it is unclear if there is a higher rate of informed choice compared to regular communication strategies at two to four weeks' follow-up (RR 1.27, 95% CI 0.83 to 1.92; 2 studies; 1805 women; low certainty evidence). These interventions result in little to no difference in anxiety (MD 0.33, 95% CI -1.55 to 0.99; scale from 20 to 80) and depression (MD 0.02, 95% CI -0.41 to 0.45; scale from 0 to 21; 2 studies; 1193 women; high certainty evidence) and lower cancer worry compared to control (MD -0.17, 95% CI -0.26 to -0.08; scale from 1 to 4; 1 study; 838 women; high certainty evidence). Other review outcomes were not measured.

AUTHORS' CONCLUSIONS

Studies using abbreviated forms of SDM and other forms of enhanced communications indicated improvements in knowledge and reduced decisional conflict. However, uncertainty remains about the effect of SDM on supporting women's decisions. Most studies did not evaluate outcomes considered important for this review topic, and those that did measured different concepts. High-quality randomised trials are needed to evaluate SDM in diverse cultural settings with a focus on outcomes such as women's satisfaction with choices aligned to their values.

[Validation of the Informed Choice instrument for Chilean women facing a mammography decision in primary care]

Objetivo

Adaptar y validar el instrumento Informed Choice (IC) para la decisión de mamografía al contexto chileno.

Diseño

Estudio transversal, analítico, de adaptación y validación psicométrica.

Emplazamiento

Centro de atención primaria del sector sur oriente de Santiago de Chile.

Métodos

1) traducir y contra-traducir IC; 2) realizar un grupo focal para la relevancia cultural/lingüística; 3) examinar la validez del contenido; 4) pilotar el instrumento; 5) aplicar para validación. Para la consistencia interna se usó el alfa de Cronbach, prueba de esfericidad de Bartlett y la medida de Kaiser-Meyer-Olkin para determinar correlaciones entre las variables y análisis factorial.

Resultados

Se construyeron 3 versiones del IC, modificándose según la opinión de usuarios y expertos. La validación se llevó a cabo en una muestra de 70 mujeres. La edad media fue de 54,4 años, el 47,1% de educación secundaria completa y el 92,9% al menos se había realizado alguna vez una mamografía. Se realizó análisis factorial del IC y se eliminó uno de sus ítems. El alfa de Cronbach final fue 0,79.

Conclusión

El uso de instrumentos de medición requiere de su validación previa ya que la versión original puede variar de acuerdo al contexto cultural donde será aplicado y las necesidades locales particulares. El proceso de validación del IC permite contar con un instrumento confiable para medir la decisión de las mujeres que deben realizarse la mamografía en la dimensión conocimiento, actitud e intención hacia el examen.

Facilitating informed decisions about breast cancer screening: development and evaluation of a web-based decision aid for women in their 40s

Background

Expert groups and national guidelines recommend individualized decision making about screening mammography for women in their 40s at low-to-average risk of breast cancer. We created Breast Screening Decisions (BSD), a personalized, web-based decision aid, to help women decide when to start and how often to have routine screening mammograms. We evaluated BSD in a large, prospective pilot trial of women and their clinicians.

Methods

Women ages 40–49 were invited to use BSD before a scheduled preventive care visit. One month post-visit, users were asked about decisional conflict, knowledge, perceptions and worry about breast cancer and screening. They were also asked whether they had a screening mammogram since their visit, scheduled an appointment for a screening mammogram, or if they were planning to schedule an appointment within the next six months. Women who responded “no” to each of these successive questions were considered to have no plan for a screening mammogram within the next 6 months, unless they explicitly stated that they were unsure about screening mammography. Clinicians were surveyed regarding mammography discussions and perceived patient knowledge and anxiety.

Results

Of 1,100 women invited to use BSD, 253 accessed the website, and 168 were eligible to participate in the pilot study. One-fifth had a family history of breast cancer, and at least 76% had any prior mammogram. At follow-up, 88% of BSD users reported discussing mammography at their visit, and 77% said they had a screening mammogram since the visit or that they made or were planning to make a screening mammogram appointment. The average decisional conflict score was 22.5, within the threshold for implementing decisions. Decisional conflict scores were lowest in women who said that they had or planned to have a mammogram (mean 21.4, 95% CI 18.3-24.6), higher in those who did not (mean 24.8, 95% CI 19.2-30.5), and highest in those who were unsure (mean 31.5, 95% CI 13.9-49.1). Most BSD users expressed accurate perceptions of their breast cancer risk and the benefits and limitations of screening.

Conclusions

A web-based decision aid may support informed, individualized decisions about screening mammography and facilitate discussions about screening between women in their 40s and their clinicians.

Electronic supplementary material

The online version of this article (doi:10.1186/s12911-017-0423-7) contains supplementary material, which is available to authorized users.

Using an informed consent in mammography screening: a randomized trial

Spanish women do not make an informed choice regarding breast cancer screening (BCS). Our aim was to evaluate the impact of receiving information regarding real BCS benefits and risks on knowledge, attitude, decision, feelings, and worries about cancer. Randomized controlled clinical trial of 355 women aged between 45 and 67 years, 177 and 178 assigned to the intervention group (IG) and control group (CG), respectively. After breast screening, women received either Nordic Cochrane Centre information on BCS or standard information. The primary outcome (knowledge) was determined from questionnaire administered at baseline and after a month. Answers were scored from 0 to 10 and scores of 5 or more indicated that women were well informed (had “good knowledge”). Questionnaires regarding attitudes, future screening intentions, and psychosocial impact were also administered. The Chi‐squared and Student's t‐tests were used to compare qualitative and quantitative variables, respectively. Good knowledge was acquired by 32 (18.10%) IG women and 15 (8.40%) CG women (P = 0.008). Mean scores from first to second interview increased from 2.97 (SD 1.16) to 3.43 (SD 1.39) in the CG and from and from 2.96 (SD 1.23) to 3.95 (SD 1.78) (P = 0.002) in the IG. No differences were found in the secondary endpoints. Women receiving information based on the Nordic Cochrane Centre document were better informed. This means of providing information is not very efficacious, nor does it modify attitude, decision, feelings, or worries about cancer.

Interventions to enhance informed choices among invitees of screening programmes-a systematic review

BACKGROUND

Informed decision making about participation has become an explicit purpose in invitations for screening programmes in western countries. An informed choice is commonly defined as based on: (i) adequate levels of knowledge of the screening and (ii) agreement between the invitee's values towards own screening participation and actual (intention to) participation.

METHODS

We systematically reviewed published studies that empirically evaluated the effects of interventions aiming at enhancing informed decision making in screening programmes targeted at the general population. We focused on prenatal screening and neonatal screening for diseases of the foetus/new-born and screening for breast cancer, cervical cancer and colorectal cancer. The Medline, EMBASE and Cochrane databases were searched for studies published till April 2012, using the terms 'informed choice', 'decision making' and 'mass screening' separately and in combination and terms referring to the specific screening programmes.

RESULTS

Of the 2238 titles identified, 15 studies were included, which evaluated decision aids (DAs), information leaflets, film, video, counselling and a specific screening visit for informed decision making in prenatal screening, breast and colorectal cancer screening. Most of the included studies evaluated DAs and showed improved knowledge and informed decision making. Due to the limited number of studies the results could not be synthesized.

CONCLUSION

The empirical evidence regarding interventions to improve informed decision making in screening is limited. It is unknown which strategies to enhance informed decision making are most effective, although DAs are promising. Systematic development of interventions to enhance informed choices in screening deserves priority, especially in disadvantaged groups.

Do women make an informed choice about participating in breast cancer screening? A survey among women invited for a first mammography screening examination

OBJECTIVE

To determine the level of informed choice in women invited for breast cancer screening for the first time.

METHODS

To determine the content of decision-relevant knowledge, 16 experts were asked to judge whether each of 51 topics represented essential information to enable informed choices. To assess the level of informed choices, a questionnaire was then sent to all 460 invited women in the south-western part of the Netherlands who turned 50 in August 2008.

RESULTS

Of all 229 respondents, 95% were deemed to have sufficient knowledge as they answered at least 8 out of 13 items correctly. In 90% there was consistency between intention (not) to participate and attitude. As a result, 88% made an informed choice. Sixty-eight percent of women responded correctly on the item of over-diagnosis. Even if all non-respondents were assumed to have no knowledge, 50% of the total group invited to participate still had sufficient knowledge.

CONCLUSIONS

Women were deemed to have sufficient relevant knowledge of the benefits and harms if they answered at least half of the items correctly.

PRACTICE IMPLICATIONS

To further increase informed choices in breast cancer screening, information on some of the possible harms merits further attention.

Closing the gap in mammogram screening: an experimental intervention among low-income Hispanic women in community health clinics

A low rate of mammogram screening exists among low-income Hispanic women. To address this disparity, an experimental intervention containing audiovisual and written media was conducted using the health belief model as a framework. The purpose of this study was to determine if low-income Hispanic women, more than 40 years of age, who received targeted cancer prevention education (n = 105) had a significantly greater perceived threat of breast cancer, greater benefits and lower barriers to screening, and stronger intentions to obtain mammograms compared to a control group (n = 105). Intervention participants reported significantly greater perceived benefits, self-efficacy, and mammogram screening intentions than the control group. Predictors of mammogram screening intentions, when controlling for covariates, included receiving the intervention, and having greater perceived benefits, self-efficacy, and lower barriers. Results demonstrate the effectiveness of a low-cost, theory-based intervention aimed at increasing mammogram screening to assist in the monitoring of Healthy People 2020 objectives.

Anthropometric measures, body mass index, and pancreatic cancer: a pooled analysis from the Pancreatic Cancer Cohort Consortium (PanScan)

BACKGROUND

Obesity has been proposed as a risk factor for pancreatic cancer.

METHODS

Pooled data were analyzed from the National Cancer Institute Pancreatic Cancer Cohort Consortium (PanScan) to study the association between prediagnostic anthropometric measures and risk of pancreatic cancer. PanScan applied a nested case-control study design and included 2170 cases and 2209 control subjects. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression for cohort-specific quartiles of body mass index (BMI [calculated as weight in kilograms divided by height in meters squared]), weight, height, waist circumference, and waist to hip ratio as well as conventional BMI categories (underweight, <18.5; normal weight, 18.5-24.9; overweight, 25.0-29.9; obese, 30.0-34.9; and severely obese, > or = 35.0). Models were adjusted for potential confounders.

RESULTS

In all of the participants, a positive association between increasing BMI and risk of pancreatic cancer was observed (adjusted OR for the highest vs lowest BMI quartile, 1.33; 95% CI, 1.12-1.58; P(trend) < .001). In men, the adjusted OR for pancreatic cancer for the highest vs lowest quartile of BMI was 1.33 (95% CI, 1.04-1.69; P(trend) < .03), and in women it was 1.34 (95% CI, 1.05-1.70; P(trend) = .01). Increased waist to hip ratio was associated with increased risk of pancreatic cancer in women (adjusted OR for the highest vs lowest quartile, 1.87; 95% CI, 1.31-2.69; P(trend) = .003) but less so in men.

CONCLUSIONS

These findings provide strong support for a positive association between BMI and pancreatic cancer risk. In addition, centralized fat distribution may increase pancreatic cancer risk, especially in women.