Breast Cancer Diagnostic Efficacy in a Developing South-East Asian Country

Background: Breast cancer, is increasing in prevalence amongst South East (SE) Asian women, highlighting the need for high quality, early diagnoses. This study investigated radiologists' detection efficacy in a developing (DC) and developed (DDC) SE Asian country, as compared to Australian radiologists. Methods: Using a test-set of 60 mammographic cases, 20 containing cancer, JAFROC figures of merit (FOM) and ROC area under the curves (AUC) were calculated as well as location sensitivity, sensitivity and specificity. The test set was examined by 35, 15, and 53 radiologists from DC, a DDC and Australia, respectively. Results: DC radiologists, compared to both groups of counterparts, demonstrated significantly lower JAFROC FOM, ROC AUC and specificity scores. DC radiologists had a significantly lower location sensitivity than Australian radiologists. DC radiologists also demonstrated significantly lower values for age, hours of reading per week, and years of mammography experience when compared with other radiologists. Conclusion: Significant differences in breast cancer detection parameters can be attributed to the experience of DC radiologists. The development of inexpensive, innovative, interactive training programs are discussed. This nonuniform level of breast cancer detection between countries must be addressed to achieve the World Health Organisation goal of health equity.

Benefits of Independent Double Reading in Digital Mammography: A Theoretical Evaluation of All Possible Pairing Methodologies.

RATIONALE AND OBJECTIVES: To establish the efficacy of pairing readers randomly and evaluate the merits of developing optimal pairing methodologies. MATERIALS AND METHODS: Sensitivity, specificity, and proportion correct were computed for three different case sets that were independently read by 16 radiologists. Performance of radiologists as single readers was compared to expected double reading performance. We theoretically evaluated all possible pairing methodologies. Bootstrap resampling methods were used for statistical analyses. RESULTS: Significant improvements in expected performance for double versus single reading (ie, delta performance) were shown for all performance measures and case-sets (p ≤ .003), with overall delta performance across all theoretically possible pairing schemes (n = 10,395) ranging between .05 and .08. Delta performance for the 20 best pairing schemes was significant (p < .001) and ranged between .07 and .10. Delta performance for 20 random pairing schemes was also significant (p ≤ .003) and ranged between .05 and .08. Delta performance for the 20 worst pairing schemes ranged between .03 and .06, reaching significance in delta proportion correct (p ≤ .021) for all three case-sets and in delta specificity for two case-sets (p ≤ .033) but not for a third case-set (p = .131), and not reaching significance in delta sensitivity for any of the three case-sets (.098 ≥ p ≥ .067). CONCLUSION: Significant benefits accrue from double reading, and while random reader pairing achieves most double reading benefits, a strategic pairing approach may maximize the benefits of double reading.

A review of factors influencing radiologists' visual search behaviour.

This narrative literature review aims to identify the various factors that have significant impact on radiologists' visual search patterns. Identifying the factors that influences readers' visual search behaviour helps to understand their perception and interpretation of medical images, which in turn could lead to the development and implementation of effective strategies that could aid in improving the ability to detect abnormalities. Databases including PubMed, MedLine, Web of Science and ScienceDirect were searched using terms 'visual search', 'eye-tracking', 'radiology OR radiography', 'mammogram OR mammography' published since the early 1960s until June 30, 2016. Some of the factors that have been identified to significantly influence radiologists' visual search patterns were (i) readers' expertise, (ii) Satisfaction of Search, (iii) readers' visual fatigue, (iv) readers' confidence in reporting abnormalities, (v) training received and (vi) readers' prior knowledge. Readers' level of expertise was the factor that has been identified to have the most significant impact on their visual search pattern. Eye-tracking studies have shown the differences in visual search patterns of readers with different levels of experience and not so surprisingly, more experienced readers have shown effective visual search strategies. Readers' expertise has also been found to have significant impact in their confidence in reporting abnormalities and their ability to discriminate lesions from background structures in medical images.