Volume 185 - Issue 10
Public reporting of hospital outcomes based on administrative data
Authors: Kerry Innes, Kirsten McKenzie and Sue Walker
Med J Aust 2006; 185 (10): 574. || doi: 10.5694/j.1326-5377.2006.tb00696.x
Published online: 20 November 2006
Published online: 20 November 2006
To the Editor: We recently read with concern the article by Scott and Ward on public reporting of hospital outcomes.1 While we do not want to enter into the debate about whether the public release of hospital performance reports is beneficial or harmful, we would like to address some issues relating to the accuracy of administrative data. The authors stated that “data are often [our italics] inaccurate, incomplete, or provide insufficient clinical detail” and that the “accuracy of diagnosis coding is vari-able”. They also mention the potential for “gaming” or “up-coding” by hospitals to make their institutions look better in public reports.
We believe the authors’ argument regarding coding inaccuracies is flawed. One of the articles they cited was not about coding accuracy but about mortality differentials between metropolitan and non-metropolitan regions.2 Another cited article quoted an example of a 100% miss rate for coding of dementia as a comorbidity that was based on only three cases.3 As the authors later stress in their article, it is important that sample size be considered when interpreting data, to ensure that the effects of random error are minimised.
We agree with the authors’ final point that distinguishing complications from presenting diagnoses (or comorbidities) is currently difficult using hospital coded data. However, the Victorian and Queensland hospital data collections now include an “alpha flag”, which is a letter attached to each coded diagnosis to indicate whether the diagnosis was present on admission to hospital or whether it arose during the episode of care. Moves are underway to introduce a minimum national requirement to use the alpha flag as one method of identifying complications arising from medical or surgical care.
There are a number of national and state initiatives that aim to ensure the national morbidity data collection is as accurate as possible and that it provides data directly related to its purpose (and therefore not necessarily useful for other purposes). There is currently a national debate about the purpose of this collection.
It is clear that there are issues surrounding the capture and coding of hospital data that are not well understood by data users. Because of that misunderstanding, reports such as the one by Scott and Ward paint an unjustifiably bleak picture of the quality of the data.
References
- Scott IA, Ward M. Public reporting of hospital outcomes based on administrative data: risks and opportunities. Med J Aust 2006; 184: 571-575.
- Vu HD, Heller RF, Lim LL, et al. Mortality after acute myocardial infarction is lower in metropolitan regions than in non-metropolitan regions. J Epidemiol Community Health 2000; 54: 590-595. 0_CBBBADFI
- Powell H, Lim LL, Heller RF. Accuracy of administrative data to assess comorbidity in patients with heart disease: an Australian perspective. J Clin Epidemiol 2001; 54: 687-693. 0_pgfId-1131019