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The phenomenological applications of strangeness changing neutral currents, particularly the Kº - Kº transition, are reviewed. In the Standard Model there are three possible contributions to this transition: the box diagram, the double penguin and the long distance dispersive amplitudes. The results obtained from a phenomenological study of the Kº - Kº amplitude are shown to depend critically on the assumptions made about the relative magnitudes of each of these contributions. Upper and lower bounds on the size of the hadronic matrix element (B) of the box diagram, amplitude are derived, assuming that this amplitude is the dominant contribution to the Kº - Kº transition. No interesting upper bound can be derived under other assumptions. Measurements of the B-meson lifetime and partial decay widths are used to restrict the allowed ranges for the parameters Ɵ-(_2) and Ɵ(_3) of the quark mixing matrix. This information is used, together with an analysis (under various assumptions) of the Kº - Kº mass matrix, to derive lower bounds on the mass of the t-quark (m(_t)) as a function of the parameter B. These bounds can also be regarded as lower bounds on B as a function of m(_t). The information from B-meson decays is used to determine the box diagram contribution to the K(_L)-K(_S) mass difference. For B < 1 this is significantly less than the experimental result. The double penguin amplitude is also estimated and a possibly large contribution to δm is found. There is no compelling phenomenological reason to include a substantial contribution to δm from long distance dispersive amplitudes.

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The measurement of productivity in health care is difficult. Studies in various specialty disciplines of medicine have identified that the variation in complexities (casemix) between departments or hospitals will vary and therefore will affect any basic productivity statistics that are produced. Radiation oncology is a discipline of medicine where no such studies into radiotherapy casemix variations and the effect that these may have on productivity measures have been performed, despite the high capital expenditure involved in the delivery of radiotherapy. Radiation oncology productivity on linear accelerators is currently measured by the number of patients treated or number of treatment fields treated per unit time (usually per hour). These statistics have been collected for many years and productivity assessments were made on the variations in these statistics that exist between departments. However, these statistics do not consider the variations in casemix that occur between departments. These complexity differences may be quite marked and therefore may strongly influence the ability of a department to achieve a high patient or treatment field throughput. This may be seen as 'reduced productivity' with no consideration of the complexity of the caseload seen in the department. In addition, future technological changes that improve patient outcome may be introduced. These changes may make treatment more complex. Using older measures of productivity such as fields per hour or patients per hour will not consider these technological changes and the subsequent changes in complexity and hence departments may be seen as less productive in the future using current methods of analysis unless a more valid measure of productivity that considers complexity variations is introduced. There have only been 3 previous attempts at developing measures of linear accelerator productivity. Each of these models have been developed empirically and have not been clinically validated. No previous attempts have been made in determining a scientifically-derived complexity model that considers the variations in treatment technique. This thesis describes research performed between 1995 and 2001. This research study???s primary aims were to study the factors that affect radiotherapy treatment time and treatment complexity and to develop a model of linear accelerator productivity that does consider complexity variations in radiotherapy treatment delivery. This model is called the Basic Treatment Equivalent (B.T.E.). This series of trials examines the old models of linear accelerator productivity, describes the derivation and validation of the BTE model both in Australasia and the United Kingdom, identifies the factors that contribute to treatment time and treatment complexity, describes the development of a pilot model of productivity of gynaecological brachytherapy and outpatient chemotherapy using similar BTE methodology, discusses the potential uses of the BTE model, recent independent reviews of BTE by other groups, and the advantages and disadvantages of using such a model. This research has shown that it is possible to identify the various factors that contribute to treatment time and treatment complexity and to derive a model of linear accelerator productivity that considers the variations in complexity. The BTE model has been clinically validated in Australia, New Zealand and a couple of departments in the United Kingdom and Canada and has been adopted as a new measure by various groups. It requires regular updating to maintain currency particularly as there are frequent improvements in radiation treatment technology. Future studies should identify the differences these technological enhancements make to productivity. The BTE derived from outpatient chemotherapy delivery and gynaecological brachytherapy delivery shows promise although these models require further research with the assistance of other departments.