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Forty-five different dry bulb onion varieties were grown and evaluated to provide a comparison of varietal characteristics including firmness, size, shape, and maturity.

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Medicines for human use worldwide are generated in part through the conduct of clinical trials. This is done to ensure safety and efficacy. The involvement of human subjects in drug trials has raised concerns for the protection of human rights. As a consequence of the medical misadventures, the Declaration of Helsinki was formulated in 1964 and revised up to 2002. Today, the International Conference of Harmonization of Good Clinical Practice of 1996 guidelines are used worldwide (including South Africa) in the conduct of clinical trials. This study took place in South Africa. The objectives of the study were to first develop an instrument to be used in identifying the current good clinical practice knowledge and training needs of clinical researchers / secondly identify the knowledge level and training needs using the designed instrument and thirdly, based on the findings, develop a Good Clinical Practice training model so as to facilitate the achievement of quality standards for the conduct of clinical trials in South Africa.

The general objective of this thesis was to improve understandings of design, conduct and analysis of randomized controlled trials (RCTs). The specific objective was to evaluate the methodological and statistical principles associated with conducting analyses of futility, a component of interim analysis, as part of the conduct of RCTs. This objective was addressed by first performing a systematic review, which included a detailed literature search, as well as data from a cohort of previously extracted studies. The systematic review was designed to identify futility analysis principles and methodologies in order to inform the design and conduct of retrospective futility analyses of two completed NCIC CTG trials. The results of these trials have been previously published; one trial met its stated endpoint and the other did not. Neither trial underwent an interim analysis of futility during its conduct. The retrospective futility analyses assessed the accuracy of frequently used methods, by comparing the results of each method to each other and to the original final analysis results. These assessments were performed at selected time points using both aggressive and conservative stopping rules. In order to increase the robustness of the comparisons, bootstrapping methods were applied. The results of this thesis demonstrate principles associated with the conduct of futility analyses and provide a basis for hypotheses-testing of optimum methodologies and their associated trade-offs. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2012-12-12 13:10:15.619