Influence on screening performance of second reading strategies in two lowvolume programs

BACKGROUND: The European Guidelines specify a minimum of 5,000 screening cases to be read yearly by radiologists carrying out second reading in non-centralized programs. This professional requirement is difficult to reach and/or to implement in regional programs covering a sparse population with a high number of participating radiology units, so that alternative blind double reading strategies must be devised. OBJECTIVE: To evaluate the effect on breast cancer screening performances of two second reading strategies used in non-centralized, low-volume programs. METHODS: Reading performances in two Swiss regional breast cancer screening programs (cantons of Wallis and Vaud), covering female populations, aged 50-69, of about 31'000 and 72'000 inhabitants were computed and compared. Both programs had similar screening regimens and organizations, but differed with respect to second reading. One setting applied a selective strategy whereby only experienced radiologists performed second reading; the other elicited not to restrict second readers on the basis of their individual screening activity. Analysis included some 140,000 mammograms performed between 1999 and 2005. RESULTS: Overall, screening performances improved with increasing total volume of reading, albeit not in a linear fashion. Regardless of setting, radiologists attained a higher level of screening accuracy when performing second rather than first readings, and incident rather than prevalent screening cases. The effect of a selective, small group of second readers appeared to impact favorably on the false-positive rate and other indicators of screening quality. As the learning curve depends on the number of mammograms read, these distinct strategies may bear different outcome in the long run. Implications and practical issues for low-volume programs are discussed.

Iowa Braille and Sight Saving School, June 30, 2002

State Agency Audit Report

Report of Recommendations to the Iowa Braille and Sight Saving School, June 30, 2003

State Agency Audit Report

Report of Recommendations to the Iowa Braille and Sight Saving School, June 30, 2004

State University Audit Report

Report of Recommendations to the Iowa Braille and Sight Saving School, June 30, 2005

Other Audit Reports - Regent Institutions

Audit report on the Iowa Braille and Sight Saving School, Vinton, Iowa, for the year ended June 30, 2006

Audit report on the Iowa Braille and Sight Saving School, Vinton, Iowa, for the year ended June 30, 2006

Report on the Iowa Braille and Sight Saving School, Vinton, Iowa, for the year ended June 30, 2007

Report on the Iowa Braille and Sight Saving School, Vinton, Iowa, for the year ended June 30, 2007

Fermat's treatise on quadrature: A new reading

The Treatise on Quadrature of Fermat (c. 1659), besides containing the first known proof of the computation of the area under a higher parabola, R x+m/n dx, or under a higher hyperbola, R x-m/n dx with the appropriate limits of integration in each case , has a second part which was not understood by Fermat s contemporaries. This second part of the Treatise is obscure and difficult to read and even the great Huygens described it as'published with many mistakes and it is so obscure (with proofs redolent of error) that I have been unable to make any sense of it'. Far from the confusion that Huygens attributes to it, in this paper we try to prove that Fermat, in writing the Treatise, had a very clear goal in mind and he managed to attain it by means of a simple and original method. Fermat reduced the quadrature of a great number of algebraic curves to the quadrature of known curves: the higher parabolas and hyperbolas of the first part of the paper. Others, he reduced to the quadrature of the circle. We shall see how the clever use of two procedures, quite novel at the time: the change of variables and a particular case of the formulaof integration by parts, provide Fermat with the necessary tools to square very easily curves as well-known as the folium of Descartes, the cissoid of Diocles or the witch of Agnesi.

Variation in performance across Swiss mammography screening programmes: the influence of reading strategy and experience.

[Abstract] Reading volume and mammography screening performance appear positively correlated. Performance was compared across organised Swiss screening programmes, which target relatively small populations. Except for accreditation of 2nd readers radiologists (restrictive vs non-restrictive strategy), Swiss programmes have similar screening regimen/procedures and duration, which maximises comparability. Variation in performance was explored in order to improve mammography practice and optimise screening performance. Indicators of quality and effectiveness were evaluated for about 200,000 screens performed over 4 screening rounds in the 3 longest-standing Swiss cantonal programmes (of Vaud, Geneva and Valais). Interval cancers were identified by linkage with cancer registries records. Most European standards of performance were met with a favourable cancer stage shift. Several performance indicators showed substantial variation across programmes. In subsequent rounds, compared with programmes (Vaud and Geneva) which accredited few 2nd readers to increase their individual reading volume, proportions of in situ lesions and of small cancers (? 1cm) were one third lower and halved, respectively, and the proportion of advanced lesions (stage II+) nearly 50% higher in the programme without a restrictive selection strategy. Discrepancy in second-year proportional incidence of interval cancers appears to be multicausal. Differences in performance could partly be explained by a selective strategy for 2nd readers and a prior experience in service screening, but not by the levels of opportunistic screening and programme attendance. This study provides clues for enhancing mammography screening performance in low-volume Swiss programmes.

Report on the Iowa Braille and Sight Saving School, Vinton, Iowa, for the year ended June 30, 2008

Report on the Iowa Braille and Sight Saving School, Vinton, Iowa, for the year ended June 30, 2008