Top PDF Risk of radiation induced cancer from screening mammography

Risk of radiation induced cancer from screening mammography

Risk of radiation induced cancer from screening mammography

MGD values for three AEC operation modes (DOSE [dose], STD [standard], CNT [contrast]) of the GE Senographe 2000DS FFDM system were analysed by Chen et al. (2012). Chen et al. (2012) concluded that the MGD differences in the three modes were mainly attributed to the mAs selected by the system. Also, the MGD, together with image quality, are usually used to evaluate the mammographic system performance. In this context, Ciraj-Bjelac et al. (2012) investigated the image quality and MGD in 17 Asian, African and Eastern European countries. They expressed concerns about the recorded MGD value in some countries (Ciraj- Bjelac et al., 2012). The outcome performance of two CR mammographic systems (Siemens Mammomat 3000 Nova with Kodak Direct View CR850 digitiser and Fuji CR system model Profect ONE with HR-BD image plate) in Brazil were assessed by Oliveira et al. (2011) and Jakubiak, Gamba, Neves, and Peixoto (2013), using both MGD and mammographic image quality. Both studies utilised a PMMA breast phantom for MGD calculation and CDMAM phantom for image quality assessment. Diagnostic mammography MGD was estimated in Ethiopia by Dellie, Rao, Admassie, and Meshesha (2013). Dellie et al. (2013) used Dance‘s conversion factors to calculate the MGD from incident air kerma. They concluded that the MGD of diagnostic mammography in Ethiopia was within the accepted ranges recommended by the Institute of Physics and Engineering in Medicine (IPEM) and the American College of Radiology (ACR) which are 2 mGy and 3 mGy, respectively (Dellie et al., 2013).
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Mathematical modelling of radiation induced cancer risk from breast screening by mammography

Mathematical modelling of radiation induced cancer risk from breast screening by mammography

In 2010, the Health Protection Agency (HPA) reported that medical and dental X-ray procedures constituted 90% of man-made radiation sources to the United Kingdom (UK) population [5]. However, the medical radiation exposure to the United States (US) population increased by 600% from 1980 to 2012 [6]. Accordingly, there is a growing need for healthcare professionals to be more conscious of the risks associated with imaging when using ionising radiation for diagnostic purposes [7]. This is particularly true for mammography breast screening programmes where asymptomatic women are imaged [8]. Also, when screening frequency is increased, because of increased risk of breast cancer [9], radiation risk also increases as a direct consequence of mammography imaging. Extra diligence should therefore be exercised when assigning a woman into a high risk cancer category in which more frequent mammography screening is required. Overall, the radiation risk from screening mammography is considered to be low [10, 11]. Nevertheless, the health profession needs to understand the radiation risks to the woman from mammography imaging, in order to justify serial imaging at any frequency level. To date, radiation risk has tended to be expressed in terms of dose to the breast (mean glandular dose, MGD) which can be a difficult concept to understand by some imaging staff and referring clinicians. Equally the woman has to make an informed decision about participating in screening taking into account the potential harm the radiation might bring against the benefit of the programme [12].
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A method for calculating effective lifetime risk of radiation induced cancer from screening mammography

A method for calculating effective lifetime risk of radiation induced cancer from screening mammography

by TLD should be less than 10%. Therefore, the TLDs sensitivity and consistency were established. In terms of sensitivity, all TLDs were exposed three times and according to their average response they were divided into five groups. The sensitivity difference for each group was less than 3%. For TLD consistency estimation, all TLDs were exposed and read three times with time intervals of around five days between the exposures then TLD responses were analysed using SPSS 20.0 (IBM, Armonk, New York, USA) to determine TLD consistency (Intra- class Correlation-Consistency). The calculated consistency was 99%. Consequently, in our work, the total uncertainty of dose results was 4%. The average background signal of three unexposed TLDs was subtracted from the readings of exposed TLDs. 24 As described by Tootell, Szczepura, and Hogg
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Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy

Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy

While the risk of second cancer development from external beam radiation therapy (EBRT) has been investigated extensively [1-3], less is known about the radiation-induced cancer risk from radionuclide therapy. Because this risk is largely dependent on the absorbed dose and dose rate in the body one would expect sizeable differences in the risk predictions between these two treatments. The absorbed dose distribution resulting from radionuclide therapy is often heterogeneously distributed throughout the body of the patient unlike the absorbed dose from EBRT that falls off rapidly as a function of distance from the tumor. The absorbed dose from radionuclide therapy is delivered continuously over an extended period of time as governed by the radionuclides half-life, which is in stark contrast to EBRT where sizable doses are delivered to a tumor volume in multiple fractions. It is impossible to relate the risks between these treatment options without accounting for these aforementioned differences.
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Optimal breast cancer screening strategies for older women: current perspectives

Optimal breast cancer screening strategies for older women: current perspectives

diabetes, nonskin cancer, chronic lung disease, heart failure, and ADL (difficulty bathing, difficulty managing finances, dif- ficulty walking several blocks, and difficulty pushing/pulling objects, etc). Application of valid prognostic tools in primary care settings may identify women with a low versus high risk of 10-year mortality that would and would not benefit from screening mammography, respectively. Recently developed decision aids show promise for counseling older women about the benefits and harms of screening mammography 74 and may
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Long term prognosis of breast cancer detected by mammography screening or other methods

Long term prognosis of breast cancer detected by mammography screening or other methods

Results: Of patients included in the main analyses (n = 1,884), 22% (n = 408) of cancers were screen-detected and 78% (n = 1,476) were detected by other methods. Breast cancer-specific 15-year survival was 86% for patients with screen-detected cancer and 66% for patients diagnosed using other methods (P < 0.0001, HR = 2.91). Similar differences in survival were observed in women at screening age (50 to 69 years), as well as in clinically important subgroups, such as patients with small tumors ( ≤ 1 cm in diameter) and without nodal involvement (N0). Women with breast cancer diagnosed on the basis of screening mammography had a more favorable prognosis than those diagnosed outside screening programs, following adjustments according to patient age, tumor size, axillary lymph node status, histological grade and hormone receptor status. Significant differences in the risk of having future contralateral breast cancer according to method of detection were not observed.
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Evaluation of the Knowledge of CT Scan Prescribers on Patients’ Radioprotection in Senegal

Evaluation of the Knowledge of CT Scan Prescribers on Patients’ Radioprotection in Senegal

Medical science uses various sources of ionizing radiation, produced either by electric generators or by radionuclides. While their medical interest and useful- ness have been established, these techniques contribute significantly to the pop- ulation’s exposure to ionizing radiation. After natural exposure, they represent the second most important source of exposure for the population and the first source of artificial origin. The current state of knowledge on the dangers and risks associated with ionizing radiation has led the international community to set health objectives for radioprotection aiming at avoiding the appearance of so-called tissue or deterministic reactions but also at reducing the probability of radiation-induced cancers [3]. The interest of knowing the risk of radia- tion-induced cancer is an element of radioprotection.
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Systematic reviews as a “lens of evidence”: determinants of benefits and harms of breast cancer screening

Systematic reviews as a “lens of evidence”: determinants of benefits and harms of breast cancer screening

This systematic review, stimulated by inconsistency in secondary evidence, reports the benefits and harms of breast cancer (BC) screening and their determinants according to systematic reviews. A systematic search, which identified 9 , 976 abstracts, led to the inclusion of 58 reviews. BC mortality reduction with screening mammography was 15 – 25% in trials and 28 – 56% in observational studies in all age groups, and the risk of stage III+ cancers was reduced for women older than 49 years. Overdiagnosis due to mammography was 1 – 60 % in trials and 1 – 12 % in studies with a low risk of bias, and cumulative false- positive rates were lower with biennial than annual screening (3 – 17% vs 0.01 – 41%). There is no consistency in the reviews’ conclusions about the magnitude of BC mortality reduction among women younger than 50 years or older than 69 years, or determinants of benefits and harms of mammography, including the type of mammography (digital vs screen-film), the number of views and the screening interval. Similarly, there was no solid evidence on determinants of benefits and harms or BC mortality reduction with screening by ultrasonography or clinical breast examination (sensitivity ranges, 54 – 84% and 47 – 69%, respectively), and strong evidence of unfavourable benefit-to-harm ratio with breast self-examination. The reviews’ conclusions were not dependent on the quality of the reviews or publication date. Systematic reviews on mammography screening, mainly from high-income countries, systematically disagree on the interpretation of the benefit-to-harm ratio. Future reviews are unlikely to clarify the discrepancies unless new original studies are published.
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Screening for breast cancer : medicalization, visualization and the embodied experience

Screening for breast cancer : medicalization, visualization and the embodied experience

wider project, that there is simultaneous confusion since some women are falsely reassured by mammography screening; feeling they are ‘OK’, that is to say risk free, for the three years after it has taken place (Griffiths et al., 2005; Griffiths et al., 2006). It is almost as though the visualized breasts, the ones dealt with by mammography, are ‘parked’ for three years. They are not part of the woman’s lived body and so remain unchanged, outside of their daily experience. This runs counter to the breast awareness message and encourages women to become less aware of their own breasts between screenings, with potentially negative implications for early detection of cancers by the women themselves. Pfeffer has noted that ‘BA [breast awareness] demands a 24/7 state of vigilance whereas, in sending out invitations every three years, the NHSBSP [National Health Service Breast Screening Programme] suggests that a different time frame is important. Women found these conflicting messages about the significance of time confusing’ and therefore may assume that screening mammography and breast awareness are ‘interchangeable’ (Pfeffer, 2004a: 228). However, at present, only half of all breast cancers found in women in the age group invited for mammography screening are diagnosed at screening. The other half, occur in women who do not attend screening or who find the cancer in the time between screenings (Advisory committee on Breast Cancer Screening, 2006).
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Promotion of early diagnosis of breast cancer in Brazilian Women

Promotion of early diagnosis of breast cancer in Brazilian Women

Background: Breast Cancer (BC) is the type of cancer that most affects women, being the second most common type in the world. In Brazil, in 2016, an estimated 57,960 new cases in women, representing 28.1% of new breast cancer cases across the country. Mammography remains the method of choice for population screening for breast cancer in asymptomatic women and is the first imaging technique indicated to evaluate most clinical breast changes. Objective: To evaluate the promotion of early diagnosis of breast cancer by performing screening mammography in women aged 50 to 69 years in the city of Teresina-PI. Method: Descriptive, prospective study with 297 women aged 50 to 69 years. For inferential analyzes, the Kolmogorov-Smirnov test, Pearson correlation and Student's t test were used. Results: The average age of the participating women was 58.4 years and 68.4% called themselves brown. The average sample estimates of developing breast cancer by the Gail model at 5 years and up to 90 years of age were 1.3% and 6.7%, respectively. Still, using the same model, 8.8% of women had an estimated risk of developing breast cancer ≥1.67% in 5 years. In the study population, there was an increase of 15.9% in the performance of screening mammographic examinations after the intervention. Conclusion: Lectures and workshops to raise awareness about breast cancer in women had positive impacts on the screening program. The sample studied had low risk estimates for developing breast cancer, according to the factors considered in the Gail model. As well, the number of screening mammograms performed during the study period was increasing compared to the previous year.
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Impact of false positive mammography on subsequent screening attendance and risk of cancer

Impact of false positive mammography on subsequent screening attendance and risk of cancer

Despite meeting most of the targets set, however, breast screening in the UK has not been an unmitigated success story. When screening was introduced there were reports of increased anxiety among the large numbers of women undergoing assessment following positive screening mammography [5]. Although most women do not show abnormalities on their screening mammograms and are simply asked to return for rescreening in 3 years, the mammograms of 5–9% of all women indicate possible malignancy. These women must undergo a second ‘assessment’ phase of the screening process, which involves further procedures such as ultrasound, needle biopsy and, possibly, open biopsy to establish a definitive diagnosis. As expected, malignancy is ruled out for the majority of women assessed, indicating that the result of their mammography was falsely positive. In the current study, the term ‘false positive’ is thus applied to any woman who is recalled for assessment on the basis of mammographic findings and in whom cancer is not diag- nosed. Other studies may limit use of the term only to those women who have undergone open biopsy with no resultant diagnosis of cancer.
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Communicating Risks to Patients and the Public

Communicating Risks to Patients and the Public

In contrast, GBA [4] is more selective in comparing pros and cons. It favours the term “disadvantage” over the term “risk”. There is no mention on alternatives. Unfortunately reader’s cognitive capabilities are over-demanded by listing too many quantitative numerical details without any assistive illustrations (Table 4). However, it is noted that it aimed at staying with whole numbers such as by mentioning 1 induced death out of 200 screended women, however, at the expense that the basis for comparison (200 women instead of a whole decade) complicates mental conversion (of those who want it) into percentages. Overall, GBA recommends systematic mammography screening with biannual mammography in women ageing 50 - 69 years. To demonstrate the benefit of graphical assistance for improved understanding, Figure 6 is inserted in this paper to demonstrate how the pool of numbers given in GBA’s “expectations” could have been visualized in a bar plot.
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Screening with magnetic resonance imaging, mammography and ultrasound in women at average and intermediate risk of breast cancer

Screening with magnetic resonance imaging, mammography and ultrasound in women at average and intermediate risk of breast cancer

suggestive of malignancy [14]. If any imaging modality was scored as BI-RADS 5, a biopsy was performed. If the modality was scored as BI-RADS 0 or 4, then a biopsy was not automatically recommended, but was done at the discretion of the treating physician and radiologist, based on the interpretation of all three screening modalities and the physical examination. In some cases, one or more screening test was repeated. In most cases, core biopsies and excisional biopsies were performed under ultrasound or stereotactic guid- ance. For BI-RADS 5 lesions that were only visualized on MRI-only, an excisional biopsy or quadrantectomy was performed. MRI-guided biopsy was not available. The biopsy specimens were reviewed by pathologists with expertise in breast cancer. Details of cancers detected were collected from hospital medical records and pathology reports. Cancers were divided into ductal carcinoma in situ (DCIS) and invasive cancer. There was one non-epithelial cancer detected (angiosarcoma). Cancers detected on the first screening round were categorized as prevalent cancers. Cancers detected on the second screening round were categorized as incident cancers. Cancers detected between screening rounds or within one year of the last screen were categorized as interval cancers. Cancers detected in the second or third year post-screening were categorized as post-screening cancers. These cancers were not considered in the evalu- ation of screening parameters (e. g. sensitivity) but were included in order to estimate the incidence rate of cancers in the cohort.
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Cost effectiveness of MRI compared to mammography for breast cancer screening in a high risk population

Cost effectiveness of MRI compared to mammography for breast cancer screening in a high risk population

Our study has some limitations that must be addressed. There are additional issues relevant to the management of women at high-risk for breast cancer that were not incor- porated in the model, and may influence the cost-effec- tiveness of screening with MRI. For example, although BRCA mutation carriers may choose to undergo prophy- lactic mastectomy, many do not choose this option, with estimates ranging from 0% to 54% of carriers [11,26]. Fur- thermore, some of the women are also at increased risk for ovarian cancer. The costs of radiation exposure due to annual mammography starting at an earlier age were not incorporated, nor were the costs of possible anxiety and stress from unnecessary biopsies stemming from false positive MRI screening. Any or all of these factors might alter the cost-effectiveness estimate. Finally, the results of our model should be interpreted with care given that the results of this cost-effectiveness analysis require compari- sons to data from observational studies, the Surveillance, Epidemiology and End Results Program, or clinical trials. All probabilities and utilities used to populate the model are estimates derived from the literature. Each of these estimates carries inherent uncertainty, as does using a hypothetical cohort. Possible selection bias associated with utilizing the Claus tables may affect our base case effectiveness and resource use estimates by either over or underestimating our base case model parameters. Moreo- ver, in our probabilistic sensitivity analysis, we did not assume that a correlation structure existed among the dis- tributions of the parameters. However, both univariate and probabilistic sensitivity analyses were performed to address uncertainty in parameter estimates by exploring variability in each probability, cost, and outcome esti- mate.
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Conclusions in systematic reviews of mammography for breast cancer screening and associations with review design and author characteristics

Conclusions in systematic reviews of mammography for breast cancer screening and associations with review design and author characteristics

Mammography is the most widely used screening technol- ogy for detecting breast cancers in asymptomatic women. Since its introduction, the relative harms and benefits of mammography have been the subject of ongoing debate. Both the age at which to begin breast cancer screening and the frequency of screening have been disputed. Conflicting recommendations persist despite decades of interventional and observational studies that are used as the basis for making recommendations [1–4], and cancer screening guidelines generally fail to quantify benefits and harms in a balanced way [5]. For mammography, the de- bate was renewed in 2009 when the US Preventive Services Task Force (USPSTF) revised their guidelines to initiate biennial screening at 50 years of age instead of 40 [6]. In 2012, the National Health Services (NHS) in the UK recommended mammography once in 3 years to women aged 47–73 years [7]. In late 2015, the American Cancer Society (ACS) updated their guidelines to initiate annual screening at 45 and reduce the frequency to biennial screening at 55 [8]. In early 2016, the USPSTF again examined the evidence and recommended biennial screening for women between the ages of 50 and 74 [9]. Conflicting recommendations about breast cancer screen- ing make it difficult for clinicians and patients to make informed choices about when to start and how often to re- peat mammography for women at average risk.
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Javaeed

Javaeed

This technique is used more in conjugation with mammography, because it is not very sensitive in itself for screening for breast cancers. It is usually applied in instances were mammography shows abnormal findings. Moreover, in case of dense breast tissue, it may reveal the diagnosis, which could have been hindered by mammography alone. 22 There are evidences available, which have shown that ultrasound can detect smaller lumps, which may be missed by mammography. For example, in one of the study, the mean size of cancer detected by mammography was 14.7 mm and by ultrasound, it was 13.5 mm. 23 The advantages of good tolerance, wide availability, no requirement of intravenous contrast or ionizing radiation and low cost compared to magnetic resonance imaging, make it a good option for a screening/diagnostic tool. However, it has a disadvantage of being greatly operator dependent. Previously there was a limitation of not being able to scan through the entire width of the breast, but recently whole breast ultrasonography has been made available. Nevertheless, its use remains significantly important, which is especially true for the Doppler Ultrasononography. It is able to detect neoangiogenesis which is present in malignancies including breast malignancy. This is supported by a study done by Cosgrove et al, which showed 99% of malignant lesions containing blood vessels could be revealed by Doppler Ultrasonography. Another study done by Raza and Vaum found 68% sensitivity and 95% specificity with Doppler Ultrasonography. It also stated 85% and 88% positive and negative predictive values respectively. It has been shown in the past, that high resolution ultrasonography can detect 3 to 4 cancers per 1000 women in asymptomatic cases. 24 Despite of this, biopsies are still generally required as a follow up or adjunct to any of the ultrasonography techniques that we currently have. Magnetic resonance imaging (MRI)
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Biokinetics, dosimetry, and radiation risk in infants after 99mTc-MAG3 scans

Biokinetics, dosimetry, and radiation risk in infants after 99mTc-MAG3 scans

National Cancer Institute. The following input data were used: gender; age; population group (U.S. 2000–2005); ex- posure year; organs like brain, breast (females), colon, gall- bladder, liver, lungs, ovaries (females), kidneys, pancreas, red bone marrow, stomach, thyroid, urinary bladder, uterus (females); exposure rate (acute); dose distribution type (fixed value); organ-specific absorbed doses [10]. The result was the percentage risk in 100,000 persons for the development of stochastic radiation-induced effects for “lifetime attributable risk” and “future risk”. The lifetime attributable risk (LAR) estimates the probability of cancer development and death by an individual arising from radi- ation exposure. The future risk is defined as the risk esti- mated for an individual from the present time until the end of the expected lifetime for developing cancer [6, 10].
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KNOWLEDGE, ATTITUDES AND PRACTICES TOWARDS BREAST CANCER SCREENING PROGRAMS AMONG IRANIAN RURAL FEMALE POPULATIONS IN NORTH OF IRAN

KNOWLEDGE, ATTITUDES AND PRACTICES TOWARDS BREAST CANCER SCREENING PROGRAMS AMONG IRANIAN RURAL FEMALE POPULATIONS IN NORTH OF IRAN

effectiveness of monthly BSE is unclear. As a significant numbers of women detect masses when they are bathing or dressing; monthly BSE can help women become more aware of their health status [10-13]. Although, there are some emphases on performing BSE, evidences show that less than 20% of Iranian women conducting regular BSE [14]. Based on the results of researches which have done in Iran, The researchers concluded that Iranian women did not know how to perform BSE [15]. The economic dependency coupled with illiteracy and ignorance particularly in rural women increases their risk of breast cancer. Researches show that rural residence itself, particularly residence in an isolated rural location, is a risk factor for not having received a screening CBE and mammogram, which lends credence to arguments for improving access to mammography in rural settings, particularly remote ones [16-18]. So, it seems that rural women have low awareness. Actually lack of knowledge about the benefit of early breast cancer screening is a significant barrier for some women to seek mammography [19]. On the other hand, on the basis of health behaviors distribution models in human society, many epidemiologists believe that the increase of knowledge and improvement of attitudes and beliefs concerning promotion of breast cancer screening programs among rural female populations [20, 21]. Several studies have shown that the knowledge and perception of rural women directly influence their attendance and accepting or screening behavior [22-25]. Although in Asia and Middle East, especially in Iran the incidence of breast cancer is rapidly increasing, but just a few studies have examined the knowledge, attitude and practice of women toward breast cancer and prevention programs in Iran. These studies are often of small sample size and targeted women in especial profession [1, 23]. In Iran, however, there are no regular population-based screening programs, and no prevention programs for controlling cancers, suggesting that knowledge about risk factors, symptoms, the benefits of early cancer-screening guidelines and the use of health care clinics for cancer treatment, especially breast cancer, may be low in the Iranian population [23-28]. In this study, we reported data derived from an investigation of the knowledge, attitudes, and practices regarding breast cancer and prevention programs, especially BSE, among Iranian rural female population.
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Should breast cancer survivors be excluded from, or invited to, organised mammography screening programmes?

Should breast cancer survivors be excluded from, or invited to, organised mammography screening programmes?

Discussion: Problems with mammographic surveillance of breast cancer survivors include: weak evidence of a reduction in mortality; lack of evidence in favour of one setting or the other; lack of evidence-based guidelines for the frequency and duration of surveillance; disproportionate emphasis placed on the first few years post-treatment, probably dictated by surgical and oncological priorities; a variety of screening policies, as these women are permanently or temporarily or partially excluded from many - but not all - organised screening programmes worldwide; an even greater disparity in follow-up protocols used in the clinical setting; a paucity of data on compliance to mammographic surveillance in both settings; and a difficulty in coordinating the roles of health care providers. In the future, the use of mammography in breast cancer survivors will be influenced by the inclusion of women aged > 69 years in organised screening programmes and the implementation of multidisciplinary breast units, and will probably be investigated by research activities on individual risk assessment and risk-tailored screening. In the interim, current problems can be partially alleviated with some technical solutions in screening data recording, patient flows, and care coordination.
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Systematic review of 3D mammography for breast cancer screening.

Systematic review of 3D mammography for breast cancer screening.

Four of the fi ve eligible studies were rated to have low risk of bias and one (Lourenco 2014 [24]) was rated to have unclear risk of bias (Table 2). Studies were rated high risk of bias based on the domain of partial veri fi cation, because follow-up was applied only to those patients recalled. Studies were also rated high risk of bias based on blinding of the application of the reference standard. In all cases this was due to the nature of the study design, as it is impossible to blind readers to the type of mammography they are reviewing. This was not considered to represent a signi fi cant risk of bias for the outcomes presented in the studies. Lourenco 2014 [24] was rated to have unclear risk of bias on 8/11 of the criteria. All three of the US studies used a retrospective observational design, and this creates the potential for confounding bias, where observed differences between screening methods are attributable to differ- ences between groups. However, all of the studies were conducted at the same sites, and patient groups were well balanced in terms of demographic factors.
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