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Introduction The detection of breast cancer is somewhat limited by human factors, and thus there is a need to improve reader performance. This study assesses whether radiologists who regularly undertake the education in the form of the Breast Reader Assessment Strategy (BREAST) demonstrate any changes in mammography interpretation performance over time. Methods In 2011, 2012 and 2013, 14 radiologists independently assessed a year-specific BREAST mammographic test-set. Radiologists read a different single test-set once each year, with each comprising 60 digital mammogram cases. Radiologists marked the location of suspected lesions without computer-aided diagnosis (CAD) and assigned a confidence rating of 2 for benign and 3–5 for malignant lesions. The mean sensitivity, specificity, location sensitivity, JAFROC FOM and ROC AUC were calculated. A Kruskal–Wallis test was used to compare the readings for the 14 radiologists across the 3 years. Wilcoxon signed rank test was used to assess comparison between pairs of years. Relationships between changes in performance and radiologist characteristics were examined using a Spearman's test. Results Significant increases were noted in mean sensitivity (P = 0.01), specificity (P = 0.01), location sensitivity (P = 0.001) and JAFROC FOM (P = 0.001) between 2011 and 2012. Between 2012 and 2013, significant improvements were noted in mean sensitivity (P = 0.003), specificity (P = 0.002), location sensitivity (P = 0.02), JAFROC FOM (P = 0.005) and ROC AUC (P = 0.008). No statistically significant correlations were shown between the levels of improvement and radiologists' characteristics. Conclusion Radiologists' who undertake the BREAST programme demonstrate significant improvements in test-set performance during a 3-year period, highlighting the value of ongoing education through the use of test-set.

Aim To compare readers' performance in detecting architectural distortion (AD) compared with other breast cancer types using digital mammography. Materials and methods Forty-one experienced breast screen readers (20 US and 21 Australian) were asked to read a single test set of 30 digitally acquired mammographic cases. Twenty cases had abnormal findings (10 with AD, 10 non-AD) and 10 cases were normal. Each reader was asked to locate and rate any abnormalities. Lesion and case-based performance was assessed. For each collection of readers (US; Australian; combined), jackknife free-response receiver operating characteristic (JAFROC), figure of merit (FOM), and inferred receiver operating characteristic (ROC), area under curve (Az) were calculated using JAFROC v.4.1 software. Readers' sensitivity, location sensitivity, JAFROC, FOM, ROC, Az scores were compared between cases groups using Wilcoxon's signed ranked test statistics. Results For lesion-based analysis, significantly lower location sensitivity ( p =0.001) was shown on AD cases compared with non-AD cases for all reader collections. The case-based analysis demonstrated significantly lower ROC Az values ( p =0.02) for the first collection of readers, and lower sensitivity for the second collection of readers ( p =0.04) and all-readers collection ( p =0.008), for AD compared with non-AD cases. Conclusions The current work demonstrates that AD remains a challenging task for readers, even in the digital era.

The aim of current work was to compare the performance of radiologists that read a higher number of cases to those that read a lower number, as well as examine the effect of number of years of experience on performance. This study compares Australian and USA radiologist with differing levels of experience when reading mammograms. Thirty mammographic cases were presented to 41 radiologists, 21 from Australia and 20 from the USA. Readers were asked to locate and visualize cancer and assign a mark-rating pair with confidence levels from 1 to 5. A jackknife free-response receiver operating characteristic (JAFROC), inferred receiver operating characteristic (ROC), sensitivity, specificity and location sensitivity were calculated. A Mann-Whitney test was used to compare the performance of Australian and USA radiologists using SPSS software. The results showed that the USA radiologists sampled had more years of experience (p≤0.01) but read less mammograms per year (p≤0.03). Significantly higher sensitivity and location sensitivity (p≤ 0.001) were found for the Australia radiologists when experience and the number of mammograms read per year were taken into account. There were no differences between the two countries in overall performance measured by JAFROC and inferred ROC. For the most experienced radiologists within the Australian sample experienced ROC and location sensitivity were higher when compared to the least experienced. The increased number of years experience of the USA radiologists did not result in an increase in any performance metrics. The number of cases per year is a better predictor of improved diagnostic performance.

Early detection of breast cancers affects the 5-year recurrence rates and treatment options for diagnosed patients, and consequently, many countries have instituted nationwide screening programs. This study compared the performance of expert radiologists from Australia and the United States in detection of breast cancer. Forty-one radiologists, 21 from Australia and 20 from the United States, reviewed 30 mammographic cases containing two-view mammograms. Twenty cases had abnormal findings and 10 cases had normal findings. Radiologists were asked to locate malignancies and assign a level of confidence. A jackknife free-response receiver operating characteristic, figure of merit (JAFROC, FOM), inferred receiver operating characteristic, area under curve (ROC, AUC), specificity, sensitivity, and location sensitivity were calculated using Ziltron software and JAFROC v4.1. A Mann-Whitney U test was used to compare the performance of Australian and U.S. radiologists. The results showed that when experience and the number of mammograms read per year were taken into account, the Australian radiologists sampled showed significantly higher sensitivity and location sensitivity ([Formula: see text]). JAFROC (FOM) and inferred ROC (AUC) analysis showed no difference between the overall performance of the two countries. ROC (AUC) and location sensitivity were higher for the Australian radiologists who read the most cases per year.

Metadata only record In 8 goats given the leaves or seeds of C. occidentalis , the main signs of poisoning were diarrhea, inappetence, dyspnoea, staggering, ataxia and recumbency. Lesions consisted of hemorrhages and congestion in the heart, lungs, abomasum and spleen, catarrhal enteritis, hepatic fatty change and necrosis, splenic haemosiderosis, pulmonary emphysema, necrosis and/or degeneration of the epithelial cells of the renal convoluted tubule, and packing of the glomeruli with endothelial and small round cells. These changes were accompanied by increases in GOT activity and in the serum concentrations of ammonia and urea, as well as by decreases in the total protein and calcium in serum. There were decreases in hemoglobin, packed cell volume and erythrocytes, and increased leukocyte counts. Total lipids were higher in the liver, kidneys and heart of the Cassia-poisoned goats than in two controls.