Radiographers supporting radiologists in the interpretation of screening mammography: a viable strategy to meet the shortage in the number of radiologists.

BackgroundAn alternative approach to the traditional model of radiologists interpreting screening mammography is necessary due to the shortage of radiologists to interpret screening mammograms in many countries.MethodsWe evaluated the performance of 15 Mexican radiographers, also known as radiologic technologists, in the interpretation of screening mammography after a 6 months training period in a screening setting. Fifteen radiographers received 6 months standardized training with radiologists in the interpretation of screening mammography using the Breast Imaging Reporting and Data System (BI-RADS) system. A challenging test set of 110 cases developed by the Breast Cancer Surveillance Consortium was used to evaluate their performance. We estimated sensitivity, specificity, false positive rates, likelihood ratio of a positive test (LR+) and the area under the subject-specific Receiver Operating Characteristic (ROC) curve (AUC) for diagnostic accuracy. A mathematical model simulating the consequences in costs and performance of two hypothetical scenarios compared to the status quo in which a radiologist reads all screening mammograms was also performed.ResultsRadiographer's sensitivity was comparable to the sensitivity scores achieved by U.S. radiologists who took the test but their false-positive rate was higher. Median sensitivity was 73.3 % (Interquartile range, IQR: 46.7-86.7 %) and the median false positive rate was 49.5 % (IQR: 34.7-57.9 %). The median LR+ was 1.4 (IQR: 1.3-1.7 %) and the median AUC was 0.6 (IQR: 0.6-0.7). A scenario in which a radiographer reads all mammograms first, and a radiologist reads only those that were difficult for the radiographer, was more cost-effective than a scenario in which either the radiographer or radiologist reads all mammograms.ConclusionsGiven the comparable sensitivity achieved by Mexican radiographers and U.S. radiologists on a test set, screening mammography interpretation by radiographers appears to be a possible adjunct to radiologists in countries with shortages of radiologists. Further studies are required to assess the effectiveness of different training programs in order to obtain acceptable screening accuracy, as well as the best approaches for the use of non-physician readers to interpret screening mammography

Los costos por préstamos y su incidencia en el financiamiento otorgado a empresas gráficas ubicadas en el distrito de Breña, periodo 2016

Determina de qué manera los costos por préstamos impactan en el financiamiento de las empresas gráficas ubicadas en el distrito de Breña, periodo 2016. Los métodos que se emplearon en el proceso de la investigación fueron: el descriptivo, estadístico, de análisis-síntesis, entre otros; que conforme con el desarrollo de la investigación se dieron indistintamente. El trabajo de campo se realizó en las empresas gráficas ubicadas en el distrito de Breña cuyo universo estuvo conformado por la totalidad de la población que estuvo conformada por los gerentes, contadores, administradores y profesionales involucrados en la gestión administrativa, haciendo un total de 32 personas, como resultado de la investigación se arribó a las siguientes conclusiones: Las altas tasas de interés aplicadas a los préstamos impiden que el estado de flujo de efectivo garantice el desarrollo de las empresas gráficas. Asimismo, la falta de información de las cargas financieras no indica el porcentaje que representan los gastos financieros con respecto a las ventas o ingresos de operación. Por último, la falta de canales de inversión en préstamos que ayuden al financiamiento para la adquisición de activos que les permita seguir creciendo

Radiographers supporting radiologists in the interpretation of screening mammography: a viable strategy to meet the shortage in the number of radiologists.

BackgroundAn alternative approach to the traditional model of radiologists interpreting screening mammography is necessary due to the shortage of radiologists to interpret screening mammograms in many countries.MethodsWe evaluated the performance of 15 Mexican radiographers, also known as radiologic technologists, in the interpretation of screening mammography after a 6 months training period in a screening setting. Fifteen radiographers received 6 months standardized training with radiologists in the interpretation of screening mammography using the Breast Imaging Reporting and Data System (BI-RADS) system. A challenging test set of 110 cases developed by the Breast Cancer Surveillance Consortium was used to evaluate their performance. We estimated sensitivity, specificity, false positive rates, likelihood ratio of a positive test (LR+) and the area under the subject-specific Receiver Operating Characteristic (ROC) curve (AUC) for diagnostic accuracy. A mathematical model simulating the consequences in costs and performance of two hypothetical scenarios compared to the status quo in which a radiologist reads all screening mammograms was also performed.ResultsRadiographer's sensitivity was comparable to the sensitivity scores achieved by U.S. radiologists who took the test but their false-positive rate was higher. Median sensitivity was 73.3 % (Interquartile range, IQR: 46.7-86.7 %) and the median false positive rate was 49.5 % (IQR: 34.7-57.9 %). The median LR+ was 1.4 (IQR: 1.3-1.7 %) and the median AUC was 0.6 (IQR: 0.6-0.7). A scenario in which a radiographer reads all mammograms first, and a radiologist reads only those that were difficult for the radiographer, was more cost-effective than a scenario in which either the radiographer or radiologist reads all mammograms.ConclusionsGiven the comparable sensitivity achieved by Mexican radiographers and U.S. radiologists on a test set, screening mammography interpretation by radiographers appears to be a possible adjunct to radiologists in countries with shortages of radiologists. Further studies are required to assess the effectiveness of different training programs in order to obtain acceptable screening accuracy, as well as the best approaches for the use of non-physician readers to interpret screening mammography

Theories and Documents of Contemporary Art : A Sourcebook of Artists' Writings

Edited by Stiles and Selz, this collection of well known artists' writings and critical texts by North American and European artists/authors draws attention to key moments in the evolution of late-modern art. The texts – manifestos, theoretical essays, interviews, letters, etc. – are placed within one of the following nine categories: Gestural Abstraction; Geometric Abstraction; Figuration; Material Culture and Everyday Life; Art and Technology; Installations, Environments and Sites; Process; Language and Concepts. Includes brief introductions to each chapter. Bibliography. Index. Circa 1300 bibl. ref