Gemma Jacklyn

Use of a decision aid including information on overdetection to support informed choice about breast cancer screening: a randomised controlled trial

BACKGROUND Mammography screening can reduce breast cancer mortality. However, most women are unaware that inconsequential disease can also be detected by screening, leading to overdiagnosis and overtreatment. We aimed to investigate whether including information about overdetection of breast cancer in a decision aid would help women aged around 50 years to make an informed choice about breast screening. METHODS We did a community-based, parallel-group, randomised controlled trial in New South Wales, Australia, using a random cohort of women aged 48-50 years. Recruitment to the study was done by telephone; women were eligible if they had not had mammography in the past 2 years and did not have a personal or strong family history of breast cancer. With a computer program, we randomly assigned 879 participants to either the intervention decision aid (comprising evidence-based explanatory and quantitative information on overdetection, breast cancer mortality reduction, and false positives) or a control decision aid (including information on breast cancer mortality reduction and false positives). Participants and interviewers were masked to group assignment. The primary outcome was informed choice (defined as adequate knowledge and consistency between attitudes and screening intentions), which we assessed by telephone interview about 3 weeks after random allocation. The primary outcome was analysed in all women who completed the relevant follow-up interview questions fully. This trial is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12613001035718. FINDINGS Between January, 2014, and July, 2014, 440 women were allocated to the intervention group and 439 were assigned to the control group. 21 women in the intervention group and 20 controls were lost to follow-up; a further ten women assigned to the intervention and 11 controls did not answer all questions on attitudes. Therefore, 409 women in the intervention group and 408 controls were analysed for the primary outcome. 99 (24%) of 409 women in the intervention group made an informed choice compared with 63 (15%) of 408 in the control group (difference 9%, 95% CI 3-14; p=0·0017). Compared with controls, more women in the intervention group met the threshold for adequate overall knowledge (122/419 [29%] vs 71/419 [17%]; difference 12%, 95% CI 6-18; p<0·0001), fewer women expressed positive attitudes towards screening (282/409 [69%] vs 340/408 [83%]; 14%, 9-20; p<0·0001), and fewer women intended to be screened (308/419 [74%] vs 363/419 [87%]; 13%, 8-19; p<0·0001). When conceptual knowledge alone was considered, 203 (50%) of 409 women in the intervention group made an informed choice compared with 79 (19%) of 408 in the control group (p<0·0001). INTERPRETATION Information on overdetection of breast cancer provided within a decision aid increased the number of women making an informed choice about breast screening. Becoming better informed might mean women are less likely to choose screening. FUNDING Australian National Health and Medical Research Council.

The global burden of occupationally related low back pain: estimates from the Global Burden of Disease 2010 study

Objectives The study was part of the Global Burden of Disease 2010 study and aimed to quantify the burden arising from low back pain (LBP) due to occupational exposure to ergonomic risk factors. Methods Exposure prevalence was based on occupation distribution; estimates of relative risk came from a meta-analysis of relevant published literature. The work-related burden was estimated as disability-adjusted life years (DALYs). Estimates were made for each of 21 world regions and 187 countries, separately for 1990 and 2010 using consistent methods. Results Worldwide, LBP arising from ergonomic exposures at work was estimated to cause 21.7 million DALYs in 2010. The overall population attributable fraction was 26%, varying considerably with age, sex and region. 62% of LBP DALYs were in males—the largest numbers were in persons aged 35–55 years. The highest relative risk (3.7) was in the agricultural sector. The largest number of DALYs occurred in East Asia and South Asia, but on a per capita basis the biggest burden was in Oceania. There was a 22% increase in overall LBP DALYs arising from occupational exposures between 1990 and 2010 due to population growth; rates dropped by 14% over the same period. Conclusions LBP arising from ergonomic exposures at work is an important cause of disability. There is a need for improved information on exposure distributions and relative risks, particularly in developing countries.

The effect of information about overdetection of breast cancer on women's decision-making about mammography screening: study protocol for a randomised controlled trial

Introduction Women are largely unaware that mammography screening can cause overdetection of inconsequential disease, leading to overdiagnosis and overtreatment of breast cancer. Evidence is lacking about how information on overdetection affects womens breast screening decisions and experiences. This study investigates the consequences of providing information about overdetection of breast cancer to women approaching the age of invitation to mammography screening. Methods and analysis This is a randomised controlled trial with an embedded longitudinal qualitative substudy. Participants are a community sample of women aged 48–50 in New South Wales, Australia, recruited in 2014. Women are randomly allocated to either quantitative only follow-up (n=904) or additional qualitative follow-up (n=66). Women in each stream are then randomised to receive either the intervention (evidence-based information booklet including overdetection, breast cancer mortality reduction and false positives) or a control information booklet (including mortality reduction and false positives only). The primary outcome is informed choice about breast screening (adequate knowledge, and consistency between attitudes and intentions) assessed via telephone interview at 2 weeks postintervention. Secondary outcomes measured at this time include decision process (decisional conflict and confidence) and psychosocial outcomes (anticipated regret, anxiety, breast cancer worry and perceived risk). Women are further followed up at 6 months, 1 and 2 years to assess self-reported screening behaviour and long-term psychosocial outcomes (decision regret, quality of life). Participants in the qualitative stream undergo additional in-depth interviews at each time point to explore the views and experiences of women who do and do not choose to have screening. Ethics and dissemination The study has ethical approval, and results will be published in peer-reviewed journals. This research will help ensure that information about overdetection may be communicated clearly and effectively, using an evidence-based approach, to women considering breast cancer screening. Trial registration number Australian New Zealand Clinical Trials Registry ACTRN12613001035718.

Overdetection in breast cancer screening: development and preliminary evaluation of a decision aid.

Objective To develop, pilot and refine a decision aid (ahead of a randomised trial evaluation) for women around age 50 facing their initial decision about whether to undergo mammography screening. Design Two-stage mixed-method pilot study including qualitative interviews (n=15) and a randomised comparison using a quantitative survey (n=34). Setting New South Wales, Australia. Participants Women aged 43–59 years with no personal history of breast cancer. Interventions The decision aid provides evidence-based information about important outcomes of mammography screening over 20 years (breast cancer mortality reduction, overdetection and false positives) compared with no screening. The information is presented in a short booklet for women, combining text and visual formats. A control version produced for the purposes of comparison omits the overdetection-related content. Outcomes Comprehension of key decision aid content and acceptability of the materials. Results Most women considered the decision aid clear and helpful and would recommend it to others. Nonetheless, the piloting process raised important issues that we tried to address in iterative revisions. Some participants found it hard to understand overdetection and why it is of concern, while there was often confusion about the distinction between overdetection and false positives. In a screening context, encountering balanced information rather than persuasion appears to be contrary to peoples expectations, but women appreciated the opportunity to become better informed. Conclusions The concept of overdetection is complex and new to the public. This study highlights some key challenges for communicating about this issue. It is important to clarify that overdetection differs from false positives in terms of its more serious consequences (overtreatment and associated harms). Screening decision aids also must clearly explain their purpose of facilitating informed choice. A staged approach to development and piloting of decision aids is recommended to further improve understanding of overdetection and support informed decision-making about screening.

Screening for Cervical, Prostate, and Breast Cancer: Interpreting the Evidence.

Cancer screening is an important component of prevention and early detection in public health and clinical medicine. The evidence for cancer screening, however, is often contentious. A description and explanation of disagreements over the evidence for cervical, breast, and prostate screening may assist physicians, policymakers, and citizens faced with screening decisions and suggest directions for future screening research. There are particular issues to be aware of in the evidence base for each form of screening, which are summarized in this paper. Five tensions explain existing conflicts over the evidence: (1) data from differing contexts may not be comparable; (2) screening technologies affect evidence quality, and thus evidence must evolve with changing technologies; (3) the quality of evidence of benefit varies, and the implications are contested; (4) evidence about harm is relatively new, there are gaps in that evidence, and there is disagreement over what it means; and (5) evidence about outcomes is often poorly communicated. The following principles will assist people to evaluate and use the evidence: (1) attend closely to transferability; (2) consider the influence of technologies on the evidence base; (3) query the design of meta-analyses; (4) ensure harms are defined and measured; and (5) improve risk communication practices. More fundamentally, there is a need to question the purpose of cancer screening and the values that inform that purpose, recognizing that different stakeholders may value different things. If implemented, these strategies will improve the production and interpretation of the methodologically challenging and always-growing evidence for and against cancer screening.

Meta-analysis of breast cancer mortality benefit and overdiagnosis adjusted for adherence: improving information on the effects of attending screening mammography.

Background:Women require information about the impact of regularly attending screening mammography on breast cancer mortality and overdiagnosis to make informed decisions. To provide this information we aimed to meta-analyse randomised controlled trials adjusted for adherence to the trial protocol.Methods:Nine screening mammography trials used in the Independent UK Breast Screening Report were selected. Extending an existing approach to adjust intention-to-treat (ITT) estimates for less than 100% adherence rates, we conducted a random-effects meta-analysis. This produced a combined deattenuated prevented fraction and a combined deattenuated percentage risk of overdiagnosis.Results:In women aged 39–75 years invited to screen, the prevented fraction of breast cancer mortality at 13-year follow-up was 0.22 (95% CI 0.15–0.28) and it increased to 0.30 (95% CI 0.18–0.42) with deattenuation. In women aged 40–69 years invited to screen, the ITT percentage risk of overdiagnosis during the screening period was 19.0% (95% CI 15.2–22.7%), deattenuation increased this to 29.7% (95% CI 17.8–41.5%).Conclusions:Adjustment for nonadherence increased the size of the mortality benefit and risk of overdiagnosis by up to 50%. These estimates are more appropriate when developing quantitative information to support individual decisions about attending screening mammography.

Carcinoma in situ of the breast in New South Wales, Australia: Current status and trends over the last 40 year

BACKGROUND The incidence of non-invasive breast cancer has increased substantially over time. We aim to describe temporal trends in the incidence of carcinoma in situ of the breast in New South Wales (NSW), Australia. METHODS Descriptive study of trends in the incidence of ductal carcinoma in situ (DCIS) and lobular carcinoma in situ (LCIS) in women who received a diagnosis from 1972 to 2012, recorded in the NSW Cancer Registry. RESULTS Carcinoma in situ as a proportion of all breast cancer was 0.4% during the prescreening period 1972 to 1987 and is currently 14.1% (2006 to 2012). Among 10,810 women diagnosed with DCIS, incidence across all ages rose from 0.15 per 100,000 during 1972 to 1983 to 16.81 per 100,000 over 2006 to 2012, representing a 100-fold increase (IRR 113.10; 95% CI 81.94 to 156.08). Among women in the target age group for screening (50-69 years) incidence rose from 0.27 per 100,000 to 51.96 over the same period (IRR 195.50; 95% CI 117.26 to 325.89). DCIS incidence peaks in women aged 60-69 years. DCIS incidence has not stabilized despite screening being well established for over 20 years, and participation rates in the target age range remaining stable. CONCLUSIONS Our findings raise questions about the value of the increasing detection of DCIS and aggressive treatment of these lesions, especially among older women, and support trials of de-escalated treatment.

Impact of extending screening mammography to older women Information to support informed choices

From 2013 through 2017, the Australian national breast cancer screening program is gradually inviting women aged 70-74 years to attend screening, following a policy decision to extend invitations to older women. We estimate the benefits and harms of the new package of biennial screening from age 50-74 compared to the previous programme of screening from age 50-69. Using a Markov model, we applied estimates of the relative risk reduction for breast cancer mortality and the risk of overdiagnosis from the Independent UK Panel on Breast Cancer Screening review to Australian breast cancer incidence and mortality data. We estimated screening specific outcomes (recalls for further imaging, biopsies, false positive and interval cancer rates) from data published by BreastScreen Australia. Compared to stopping at age 69, screening 1000 women to age 74 is likely to avert one more breast cancer death, with an additional 78 women receiving a false positive result and another 28 women diagnosed with breast cancer, of whom eight will be overdiagnosed and overtreated. The extra five years of screening results in approximately seven more overdiagnosed cancers to avert one more breast cancer death. Thus extending screening mammography in Australia to older women results in a less favourable harm to benefit ratio than stopping at age 69. Supporting informed decision making for this age group should be a public health priority. This article is protected by copyright. All rights reserved.From 2013 through 2017, the Australian national breast cancer screening programme is gradually inviting women aged 70–74 years to attend screening, following a policy decision to extend invitations to older women. We estimate the benefits and harms of the new package of biennial screening from age 50–74 compared with the previous programme of screening from age 50–69. Using a Markov model, we applied estimates of the relative risk reduction for breast cancer mortality and the risk of overdiagnosis from the Independent UK Panel on Breast Cancer Screening review to Australian breast cancer incidence and mortality data. We estimated screening specific outcomes (recalls for further imaging, biopsies, false positives, and interval cancer rates) from data published by BreastScreen Australia. When compared with stopping at age 69, screening 1,000 women to age 74 is likely to avert one more breast cancer death, with an additional 78 women receiving a false positive result and another 28 women diagnosed with breast cancer, of whom eight will be overdiagnosed and overtreated. The extra 5 years of screening results in approximately 7 more overdiagnosed cancers to avert one more breast cancer death. Thus extending screening mammography in Australia to older women results in a less favourable harm to benefit ratio than stopping at age 69. Supporting informed decision making for this age group should be a public health priority.

How information about overdetection changes breast cancer screening decisions: a mediation analysis within a randomised controlled trial

Objectives In a randomised controlled trial, we found that informing women about overdetection changed their breast screening decisions. We now present a mediation analysis exploring the psychological pathways through which study participants who received the intervention processed information about overdetection and how this influenced their decision-making. We examined a series of potential mediators in the causal chain between exposure to overdetection information and women’s subsequently reported breast screening intentions. Design Serial multiple mediation analysis within a randomised controlled trial. Setting New South Wales, Australia. Participants 811 women aged 48–50 years with no personal history of breast cancer. Interventions Two versions of a decision aid giving women information about breast cancer deaths averted and false positives from mammography screening, either with (intervention) or without (control) information on overdetection. Main outcome Intentions to undergo breast cancer screening in the next 2–3 years. Mediators Knowledge about overdetection, worry about breast cancer, attitudes towards breast screening and anticipated regret. Results The effect of information about overdetection on women’s breast screening intentions was mediated through multiple cognitive and affective processes. In particular, the information led to substantial improvements in women’s understanding of overdetection, and it influenced—both directly and indirectly via its effect on knowledge—their attitudes towards having screening. Mediation analysis showed that the mechanisms involving knowledge and attitudes were particularly important in determining women’s intentions about screening participation. Conclusions Even in this emotive context, new information influenced women’s decision-making by changing their understanding of possible consequences of screening and their attitudes towards undergoing it. These findings emphasise the need to provide good-quality information on screening outcomes and to communicate this information effectively, so that women can make well-informed decisions. Trial registration number This study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12613001035718) on 17 September 2013.

The importance of enabling informed decision making for women considering breast cancer screening

Sasieni et al. have commented on our Lancet report of a randomised controlled trial of a breast screening decision aid. We disagree with the authors on several points. While the majority of women who received the intervention decision aid found it to be either completely balanced (43%) or slanted towards screening (21%), some considered it a little (30%) or clearly (6%) slanted away from screening. Women’s attitudes to breast screening tend to be strongly favourable, having been shaped by decades of promotional campaigns designed to persuade them of the benefits of screening, without explaining the risk of overdetection. Because women are accustomed to receiving positive messages about screening that strongly endorse participation, it is not surprising that some perceived the decision aid, which aimed to present a more balanced and complete picture, as slanted away from screening. As a participant in our decision aid piloting interviews explained: