Hui and Walter's latent-class model extended to estimate diagnostic test properties from surveillance data: a latent model for latent data

Diagnostic test sensitivity and specificity are probabilistic estimates with far reaching implications for disease control, management and genetic studies. In the absence of 'gold standard' tests, traditional Bayesian latent class models may be used to assess diagnostic test accuracies through the comparison of two or more tests performed on the same groups of individuals. The aim of this study was to extend such models to estimate diagnostic test parameters and true cohort-specific prevalence, using disease surveillance data. The traditional Hui-Walter latent class methodology was extended to allow for features seen in such data, including (i) unrecorded data (i.e. data for a second test available only on a subset of the sampled population) and (ii) cohort-specific sensitivities and specificities. The model was applied with and without the modelling of conditional dependence between tests. The utility of the extended model was demonstrated through application to bovine tuberculosis surveillance data from Northern and the Republic of Ireland. Simulation coupled with re-sampling techniques, demonstrated that the extended model has good predictive power to estimate the diagnostic parameters and true herd-level prevalence from surveillance data. Our methodology can aid in the interpretation of disease surveillance data, and the results can potentially refine disease control strategies.

Sir Robert Hart Photo Collection on Flickr

The photographs in this album were selected with the assistance of the Sir Robert Hart Research Project, which is a collaboration between Special Collections & Archives in the Library, the School of Modern History & Anthropology, Queen’s University Belfast, and the Institute of Modern History at the Chinese Academy of Social Sciences (CASS) in Beijing. The research project is creating an annotated photobook from the Sir Robert Hart Photo Collection (originally donated in the 1970s) and the Irons Collection. The photographs here reflect those that will be included in the book.

Walter Heissig, Rüdiger, Schott, Die Heutige Bedeutung Oraler traditionen. IHRE Archivierung, Publikation und index-Erschießung

The book under review is the publication of 28 contributions to a workshop which has tak en place in St. Augustin, near Bonn, in November 1995. This was attended by a large number of proeminent scholars, gathered around the commonly felt concern for the need to preserve “the oral traditions of all kinds” (p. 26). The papers, written in German (11), in English (16) and in French (1), are introduced by the organisers Walter Hessig and Rüdiger Schott in both German and English.

Letter, Georgetown, SC, to Oliver Hawes Spencer, Chesterfield, SC, 1832 July 26

This letter is from E. Materman to O. H. Spencer.

Sir John Dering due date card

This is a due date card for the book titled Sir John Dering, with stamped dates from 1939-1940.