Danish Women Make Decisions about Participation in Breast Cancer Screening prior to Invitation Information: An Online Survey Using Experimental Methods.

INTRODUCTION: At mammography screening invitation, the Danish Health Authority recommends women aged 50 to 69 y make an informed decision about whether to be screened. Previous studies have shown that women have very positive attitudes about screening participation. Therefore, we hypothesized that Danish women may already have decided to participate in breast cancer screening prior to receiving their screening invitation at age 50 y. METHODS: We invited a random sample of 2,952 Danish women aged 44 to 49 y (prescreening age) to complete an online questionnaire about barriers to informed screening decision making using the official digital mailbox system in Denmark. We asked participants about their screening intentions using 3 different questions to which women were randomized: screening presented 1) as an opportunity, 2) as a choice, and 3) as an opportunity plus a question about women's stage of decision making. All women completed questions about background characteristics, intended participation in the screening program, use and impact of screening information, and preferences for the decision-making process. Data were linked to sociodemographic register data. RESULTS: A total of 790 (26.8%) women participated in the study. Herein, 97% (95% confidence interval: 96%-98%) reported that they wanted to participate in breast cancer screening when invited at age 50 y. When presented with the choice compared with the opportunity framing, more women rejected screening. When asked about their stage of decision making, most (87%) had already made a decision about screening participation and were unlikely to change their mind. CONCLUSION: In our study, almost all women of prescreening age wanted to participate in breast cancer screening, suggesting that providing information at the time of screening invitation may be too late to support informed decision making. HIGHLIGHTS: Almost all women of prescreening age (44-49 y) in our study wanted to participate in the Danish national mammography screening program starting at age 50 y.Early decision making represents a barrier for informed decision making as women in this study had intentions to participate in breast cancer screening prior to receiving an official screening invitation, and therefore, providing information at the time of screening invitation may be too late to support informed decision making.Very few women rejected screening participation; however, more women rejected screening when the information was framed as an active choice between having or declining breast cancer screening (continue with usual care) compared with presenting only the option of screening with no description of the alternative.Two-thirds of women reading the screening information in this study had unchanged attitudes toward screening after reading the presented information.

Benefits and Harms of Mammography Screening in 75 + Women to Inform Shared Decision-making: a Simulation Modeling Study.

BACKGROUND: Guidelines recommend shared decision-making (SDM) around mammography screening for women ≥ 75 years old. OBJECTIVE: To use microsimulation modeling to estimate the lifetime benefits and harms of screening women aged 75, 80, and 85 years based on their individual risk factors (family history, breast density, prior biopsy) and comorbidity level to support SDM in clinical practice. DESIGN, SETTING, AND PARTICIPANTS: We adapted two established Cancer Intervention and Surveillance Modeling Network (CISNET) models to evaluate the remaining lifetime benefits and harms of screening U.S. women born in 1940, at decision ages 75, 80, and 85 years considering their individual risk factors and comorbidity levels. Results were summarized for average- and higher-risk women (defined as having breast cancer family history, heterogeneously dense breasts, and no prior biopsy, 5% of the population). MAIN OUTCOMES AND MEASURES: Remaining lifetime breast cancers detected, deaths (breast cancer/other causes), false positives, and overdiagnoses for average- and higher-risk women by age and comorbidity level for screening (one or five screens) vs. no screening per 1000 women. RESULTS: Compared to stopping, one additional screen at 75 years old resulted in six and eight more breast cancers detected (10% overdiagnoses), one and two fewer breast cancer deaths, and 52 and 59 false positives per 1000 average- and higher-risk women without comorbidities, respectively. Five additional screens over 10 years led to 23 and 31 additional breast cancer cases (29-31% overdiagnoses), four and 15 breast cancer deaths avoided, and 238 and 268 false positives per 1000 average- and higher-risk screened women without comorbidities, respectively. Screening women at older ages (80 and 85 years old) and high comorbidity levels led to fewer breast cancer deaths and a higher percentage of overdiagnoses. CONCLUSIONS: Simulation models show that continuing screening in women ≥ 75 years old results in fewer breast cancer deaths but more false positive tests and overdiagnoses. Together, clinicians and 75 + women may use model output to weigh the benefits and harms of continued screening.

Women's health literacy and attendance in breast cancer screening: a Danish population-based study combining survey and register data.

AIM: To investigate the association between women's health literacy and attendance in the Danish national breast cancer screening programme. METHODS: In a population-based cross-sectional study, information on two health literacy subscales, measured using the Health Literacy Questionnaire (HLQ), and sociodemographic factors was obtained from the 'How are you? 2017' survey in the Central Denmark Region. Information on screening attendance was obtained from register data from 2016-2017. Data were linked based on individual civil registration numbers. To account for missing data, multiple imputation by chained equations was implemented to fill in missing values on all variables. Unadjusted and adjusted logistic regression analyses were performed separately for two HLQ subscales to estimate odds ratio (OR) of screening attendance. Both multiple imputation analyses and complete case analyses were performed. RESULTS: A total of 6012 women were included in multiple imputed statistical analyses. Generally, women had high health literacy levels. In multiple imputed analyses, the unadjusted OR of the primary HLQ subscale, understanding, was 1.32 (95% confidence interval (CI): 1.10-1.59), indicating higher odds for screening attendance with higher health literacy level. However, after adjustment no significant association between the HLQ subscale of understanding and screening attendance was found (OR 1.09 (95% CI: 0.90-1.33)). Similar results were found for the secondary HLQ subscale of engaging (insignificant association in adjusted analysis). No effect modification from sociodemographic characteristics was found. Similar results were found in complete case analyses. CONCLUSIONS: No significant association was found between health literacy and attendance in the Danish breast cancer screening programme.

Danish Women Want to Participate in a Hypothetical Breast Cancer Screening with Harms and No Reduction in Mortality: A Cross-Sectional Survey.

INTRODUCTION: Informed decision making is recommended in breast cancer screening. Decision aids with balanced information on harms and benefits are recommended to support informed decision making. However, informed screening decision making may be challenged by overly positive attitudes toward cancer screening. We hypothesized that a substantial proportion of Danish women would want to participate in screening regardless of the presented information. Therefore, we aimed to estimate the prevalence of Danish women wanting to participate in a hypothetical breast cancer screening offering no reduction in breast cancer mortality but potential harms related to unnecessary treatment. METHODS: In a cross-sectional study, we invited a random sample of 751 women in the nonscreening population aged 44 to 49 y in the Central Denmark Region to an online questionnaire using the official digital mailbox system. The questionnaire included a description of a hypothetical screening and questions about thoughts on breast cancer, health literacy, and questions on the assessment of the hypothetical screening including intended participation, understanding, and belief in information. Data were linked to register data on sociodemographic factors. RESULTS: In total, 43.0% (323/751) responded to the questionnaire. Of these, 247 (82.3% [95% confidence interval: 77.5-86.5]) wanted to participate in the hypothetical breast cancer screening (participation group). More than two-thirds in both the participation group and nonparticipation group seemed to understand the presented information. Half of the women who understood the information disbelieved it. CONCLUSIONS: Exceeding our expectations, a majority of women wanted to participate in a hypothetical screening with potential harms but no reduction in breast cancer mortality. A large proportion understood but disbelieved the screening information. This could indicate that Danish women make their screening decisions based on beliefs rather than presented screening information. This study was registered at ClinicalTrials.gov (Identifier: NCT04509063). HIGHLIGHTS: The majority of Danish women wanted to participate in a hypothetical breast cancer screening with potential harms related to unnecessary treatment but no reduction in mortality.A large proportion of women understood but disbelieved the hypothetical screening information.Informed decision making may be challenging when women disbelieve the information they receive.Enthusiasm for cancer screening and potential disbelief in information are important factors when developing and improving screening information and invitation.

Predicting difference in mean survival time from cause-specific hazard ratios for women diagnosed with breast cancer.

BACKGROUND: Relative reduction in breast cancer mortality is the preferred outcome measure for evaluation of mammography screening. However, mean survival time has been advocated as a better and more intuitive outcome for risk communication. We have previously introduced a method to predict difference in mean survival time from empirical hazard ratios for all-cause mortality. In this article, we aim to investigate the association between hazard ratios for breast cancer mortality and the difference in mean survival time for women diagnosed with breast cancer. METHODS: We retrieved data on all women diagnosed with first-time invasive breast cancer in Norway from 1960 through 2004. Women were followed until emigration or end of follow-up on 31 December 2015, whichever came first. Observed differences in mean survival times and hazard ratios for both breast cancer death and death from causes other than breast cancer were obtained for neighbouring time periods defined by women's age and year of diagnosis. Based on previously developed methods, we fitted a linear relationship between observed differences in mean survival and logarithmic hazard ratios. RESULTS: A linear association was found between breast cancer-specific hazard ratios and difference in mean survival time for women diagnosed with breast cancer. This association was also estimated with adjustment for other causes of death than breast cancer. CONCLUSIONS: The change in mean survival time could be predicted from an estimated reduction in breast cancer mortality. This outcome measure can contribute to better and more understandable risk information about the effect of mammography screening programmes.