Women's conceptual knowledge about breast cancer screening and overdiagnosis in Norway: a cross-sectional study.

Objective: To investigate conceptual knowledge about mammographic screening among Norwegian women.

Design: We administered a cross-sectional, web-based survey. We used multiple-choice questions and a grading rubric published by a research group from Australia.

Visualization of the Nipple in Profile: Does It Really Affect Selected Outcomes in Organized Mammographic Screening?

Objective: To investigate whether having the nipple imaged in profile was associated with breast characteristics or compression parameters, and whether it affected selected outcomes in screening with standard digital mammography or digital breast tomosynthesis.

Methods: In this IRB-approved retrospective study, results from 87 450 examinations (174 900 breasts) performed as part of BreastScreen Norway, 2016-2019, were compared by nipple in profile status and screening technique using descriptive statistics and generalized estimating equations. Unadjusted and adjusted odds ratios with 95% confidence intervals (95% CIs) were estimated for outcomes of interest, including age, breast volume, volumetric breast density, and compression force as covariates.

Digital breast tomosynthesis in a population based mammographic screening program: Breast compression and early performance measures.

Purpose: We aimed to determine if compression force or pressure could be associated with early performance measures for women screened with digital breast tomosynthesis (DBT) in BreastScreen Norway. Early performance measures included rates of consensus, recall, and screen-detected breast cancer.

Method: Data on compression force and pressure, compressed breast thickness and breast characteristics were extracted from an automated software for density assessment of DBT screening examinations for 25,286 women.

Assessment of breast positioning criteria in mammographic screening: Agreement between artificial intelligence software and radiographers.

Objectives: To determine the agreement between artificial intelligence software (AI) and radiographers in assessing breast positioning criteria for mammograms from standard digital mammography and digital breast tomosynthesis.

Methods: Assessment of breast positioning was performed by AI and by four radiographers in pairs of two on 156 examinations of women screened in Bergen, April to September 2019, as part of BreastScreen Norway. Ten criteria were used; three for craniocaudal and seven for mediolateral-oblique view.

Screening at stationary versus mobile units in BreastScreen Norway.

Objective: To compare breast characteristics, compression parameters, and early performance measures (rates of recall, screen-detected and interval breast cancer, and histopathologic tumour characteristics) for mammographic screening at a stationary versus mobile screening unit.

Methods: Results from 92,408 mammographic screening examinations performed as part of BreastScreen Norway during 2008–2017 at either a stationary (n = 52,620) or mobile (n = 39,788) unit in Hordaland county were compared using descriptive statistics and generalized estimating equations. A generalized estimating equation for a binary outcome was used to estimate crude and adjusted odds ratios with 95% confidence intervals for the outcomes of interest.

Breast compression across consecutive examinations among females participating in BreastScreen Norway.

Objective::  Breast compression is used in mammography to improve image quality and reduce radiation dose. However, optimal values for compression force are not known, and studies have found large variation in use of compression forces between breast centres and radiographers. We investigated breast compression parameters, including compression force, compression pressure and compressed breast thickness across four consecutive full field digital mammography screening examinations for 25,143 subsequently screened females aged 50-69 years.

The impact of compression force and pressure at prevalent screening on subsequent re-attendance in a national screening program.

Adherence to screening may indirectly help assess whether a prior screening examination deters women from returning for a subsequent examination. We investigated whether compression force and pressure in mammography were associated with re-attendance among prevalently screened women in the organized breast cancer screening program in Norway. Data on compression force (kg) and pressure (kPa) from women's first screening examination in the program (prevalent screening) and subsequent re-attendance were available for 31,225 women aged 50-68, screened during 2007-2013.

Breast compression parameters and mammographic density in the Norwegian Breast Cancer Screening Programme.

Objectives: To investigate possible associations between breast compression parameters, including compression force, pressure and compressed breast thickness, and mammographic density assessed by an automated software.

Methods: We obtained data on breast compression parameters, breast volume, absolute and percentage dense volume, and body mass index for 14,698 women screened with two-view (craniocaudal, CC, and mediolateral oblique, MLO) digital mammography, in the Norwegian Breast Cancer Screening Programme, 2014-2015. The Spearman correlation coefficient (ρ) was used to measure correlation between breast compression parameters, breast volume and absolute and percentage dense volume.

Comparison of subjective and fully automated methods for measuring mammographic density.

Background Breast radiologists of the Norwegian Breast Cancer Screening Program subjectively classified mammographic density using a three-point scale between 1996 and 2012 and changed into the fourth edition of the BI-RADS classification since 2013. In 2015, an automated volumetric breast density assessment software was installed at two screening units. Purpose To compare volumetric breast density measurements from the automated method with two subjective methods: the three-point scale and the BI-RADS density classification.

Compression force and radiation dose in the Norwegian Breast Cancer Screening Program.

Purpose: Compression force is used in mammography to reduce breast thickness and by that decrease radiation dose and improve image quality. There are no evidence-based recommendations regarding the optimal compression force. We analyzed compression force and radiation dose between screening centers in the Norwegian Breast Cancer Screening Program (NBCSP), as a first step towards establishing evidence-based recommendations for compression force.

Compression forces used in the Norwegian Breast Cancer Screening Program.

Objective: Compression is used in mammography to reduce breast thickness, which is claimed to improve image quality and reduce radiation dose. In the Norwegian Breast Cancer Screening Program (NBCSP), the recommended range of compression force for full-field digital mammography (FFDM) is 11-18 kg (108-177 N). This is the first study to investigate the compression force used in the programme.

Impact of errors in recorded compressed breast thickness measurements on volumetric density classification using volpara v1.5.0 software.

Purpose: Mammographic density has been demonstrated to predict breast cancer risk. It has been proposed that it could be used for stratifying screening pathways and recommending additional imaging. Volumetric density tools use the recorded compressed breast thickness (CBT) of the breast measured at the x-ray unit in their calculation; however, the accuracy of the recorded thickness can vary.