The effects of normalisation on the ability of business end-users to detect data anomalies: An experimental evaluation

With the proliferation of relational database programs for PC's and other platforms, many business end-users are creating, maintaining, and querying their own databases. More importantly, business end-users use the output of these queries as the basis for operational, tactical, and strategic decisions. Inaccurate data reduce the expected quality of these decisions. Implementing various input validation controls, including higher levels of normalisation, can reduce the number of data anomalies entering the databases. Even in well-maintained databases, however, data anomalies will still accumulate. To improve the quality of data, databases can be queried periodically to locate and correct anomalies. This paper reports the results of two experiments that investigated the effects of different data structures on business end-users' abilities to detect data anomalies in a relational database. The results demonstrate that both unnormalised and higher levels of normalisation lower the effectiveness and efficiency of queries relative to the first normal form. First normal form databases appear to provide the most effective and efficient data structure for business end-users formulating queries to detect data anomalies.

Bond Strength of Fiber Posts to Weakened Roots After Resin Restoration With Different Light-Curing Times

Introduction: This study evaluated the bond strength of translucent fiber posts to experimentally weakened radicular dentin restored with composite resin and polymerized with different light-exposure time. Methods: Roots of 60 maxillary incisors were used. Twenty-four hours after obturation, the filling materials of root canals were removed to a depth of 12 mm, and 4 groups were randomly formed. In 3 groups, root dentin was flared to produce a space between fiber post and canal walls. In the control group, the roots were not experimentally weakened. The flared roots were bulk restored with composite resin, which was light-activated through the translucent post for 40, 80, or 120 seconds. Posts were cemented, and after 24 hours, all roots were sectioned transversely in the coronal, middle, and apical regions, producing 1-mm-thick slices. Push-out test was performed, and failure modes were observed. Results The quantitative analysis showed significant statistical difference only among groups (P <.001). Comparing the weakened/restored groups, composite light-exposure time did not influence the results. Overall, adhesive failures occurred more frequently than other types of failures. Cohesive failures occurred only in the weakened/restored roots. Conclusions Intracanal root restoration with composite resin and translucent fiber posts provided similar or higher bond strength to dentin than the control group, regardless of the light-exposure time used for polymerization. (J Endod 2009;35:1034-1039)

Tactics at the interface: Australian Aboriginal and Torres Strait Islander health managers

Over the past thirty years in Australia, there has been a recognition of the need for increasing Aboriginal and Torres Strait Islander participation in the management of their health services as part of the strategy to improve the poor health of Australia's indigenous peoples. The proliferation of Aboriginal Community-Controlled Health Services and the vigorous advocacy of groups such as the National Aboriginal Community Controlled Health Organisation have significantly contributed to this recognition. This, combined with additional management opportunities in government service, has drawn attention to difficulties in recruiting and retaining appropriately experienced Aboriginal and Torres Strait Islander managers, particularly in the northern states of Australia. (C) 2001 Elsevier Science Ltd. All rights reserved.

Health services research using linked records: who consents and what is the gain?

Objective: To assess consent to record linkage, describe the characteristics of consenters and compare self-report versus Medicare records of general practitioner use. Method. Almost 40,000 women in the Australian Longitudinal Study on Women's Health were sent a request by mail for permission to link their Medicare records and survey data. Results: 19,700 women consented: 37% of young (18-23 years), 59% of mid-age (4550 years) and 53% of older women (70-75 years). Consenters tended to have higher levels of education and, among the older cohort, were in better health than nonconsenters. Women tended to under-report the number of visits to general practitioners. Conclusions: Record linkage of survey and Medicare data on a large scale is feasible. The linked data provide information on health and socio-economic status which are valuable for understanding health service utilisation. Implications: Linked records provide a powerful tool for health care research, particularly in longitudinal studies.