Development of a validation algorithm for 'present on admission' flagging

Background. The use of routine hospital data for understanding patterns of adverse outcomes has been limited in the past by the fact that pre-existing and post-admission conditions have been indistinguishable. The use of a 'Present on Admission' (or POA) indicator to distinguish pre-existing or co-morbid conditions from those arising during the episode of care has been advocated in the US for many years as a tool to support quality assurance activities and improve the accuracy of risk adjustment methodologies. The USA, Australia and Canada now all assign a flag to indicate the timing of onset of diagnoses. For quality improvement purposes, it is the 'not-POA' diagnoses (that is, those acquired in hospital) that are of interest. Methods. Our objective was to develop an algorithm for assessing the validity of assignment of 'not-POA' flags. We undertook expert review of the International Classification of Diseases, 10th Revision, Australian Modification (ICD-10-AM) to identify conditions that could not be plausibly hospital-acquired. The resulting computer algorithm was tested against all diagnoses flagged as complications in the Victorian (Australia) Admitted Episodes Dataset, 2005/06. Measures reported include rates of appropriate assignment of the new Australian 'Condition Onset' flag by ICD chapter, and patterns of invalid flagging. Results. Of 18,418 diagnosis codes reviewed, 93.4% (n = 17,195) reflected agreement on status for flagging by at least 2 of 3 reviewers (including 64.4% unanimous agreement; Fleiss' Kappa: 0.61). In tests of the new algorithm, 96.14% of all hospital-acquired diagnosis codes flagged were found to be valid in the Victorian records analysed. A lower proportion of individual codes was judged to be acceptably flagged (76.2%), but this reflected a high proportion of codes use

Population ageing and dental care

Population ageing is a fact in both developed and developing countries. The concern about population ageing largely arises from the combination of a greater number of older people requiring greater amounts of healthcare services and pensions, and relatively fewer people working to pay for them. Oral health and dental care are important aspects of health and health care. Lower rates of edentulism and an ageing population mean that older people will feature more prominently in dental services. Traditionally, economic studies of ageing have focused on the fiscal implications of ageing, projecting the increased burden on health and welfare services that accompanies ageing. It assumed that ageing is the major driver of recent changes and those past trends will simply be amplified by faster population ageing in the future. Less work has been done to understand other past drivers of increased healthcare spending and their implications for the future. The conclusion of these reports is usually that population ageing is unaffordable with current policy settings. They have proposed policies to deal with population ageing which focused on increasing workforce participation and worker productivity to increase the tax base and reducing entitlements. However, the affordability question is as much political as a numerical. There are no clearly articulated criteria for affordability and little opportunity for public discourse about what citizens are willing to pay in taxes to support an ageing population. While the reports do not necessarily reflect public opinion, they will certainly shape it. Predicting the future for oral health is more fraught than for general health, as oral health is in the midst of an epidemiological transition from high rates of edentulism and tooth loss to low rates. Changes in the pattern of dental expenditure in the past do not mirror the experience of rapid increases in per capita expenditure on older age groups as regards general health. Dentistry's marginal status means that less work has been done to understand the future consequences of these changes and how they will interact with population ageing. Further than this though, we need to understand why the future might look as these projections suggest, so that we may look at ways that it can be shaped.Jane Harfor