Measuring the true impact of an electronic physiological surveillance system (EPSS)

Dear Sir, We read with interest the article by Schmidt et al. We applaud the authors for undertaking this large and complex study and for highlighting the great potential of newer technologies to improve patient care. We hoped the authors could clarify some key issues. Firstly only one year's mortality data are used as a baseline comparator. Mortality fluctuates by year as this paper highlights, and can be affected by a large number of factors including how it is expressed (1). It is possible that the year chosen may have been an outlier that triggered the Trusts to actively invest in measures including EPSS. We would therefore be grateful if the authors could provide additional data on mortality in the years prior to the intervention. Were other strategies employed alongside EPSS? For example we understand University Hospital Coventry also called in Dr Foster Intelligence in 2007 to restructure practice (2). As the paper uses only a historical comparator it is possible that a proportion of the improvement reflects the general national improvement in hospital mortality seen over the last decade (3). Do the authors have any data comparing their improvements with other Trusts of a similar size, case-mix, and similarly average HSMR (4)? Interventions in healthcare are rarely without some adverse effects and as such we would be interested in any data collected on the potential negative aspects. These would include consequences of the increased workload for junior doctors and financial effect cost. Establishing that these were relatively minor would be very reassuring for other Trusts considering similar strategies. While we agree that randomised controlled trials are complex, we suggest there is a strong rationale for them to disaggregate the benefit of EPSS from many confounding factors, and to inform clear health economic analysis. Yours sincerely, Dominick Shaw, John Blakey and Jamie Rylance 1 http://www.nejm.org/doi/full/10.1056/NEJMsa1006396#t=articleMethods 2 http://drfosterintelligence.co.uk/wp-content/uploads/2013/02/University-Hospitals-Coventry-Warwickshire-NHS-Trust-case-study.pdf 3 http://www.biomedcentral.com/1472-6963/13/216 4 http://drfosterintelligence.co.uk/wp-content/uploads/2011/11/Hospital_Guide_2011.pdf

Conflict of Interest:

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