When reports include claims that are clearly wrong, I wouldn't trust their entirety. That's the case with the recently released "Impact of Healthcare-associated Infections in Pennsylvania 2010." Dan and Mike have every reason to be surprised by the very very low infection rates. I too hope that more details concerning the validation of the HAIs will be provided soon.
However, I don't think we have to wait for more details to see that the report is seriously flawed. The error is so obvious (and so frequently repeated in other reports), that it should almost make us laugh. The serious error is that the Pennsylvania report attempts to estimate the costs and excess length of stay associated with hospital infections by including the outcomes that manifest BEFORE the infection.
For a better explanation, here is what we said in the methods of a recent Archives of Internal Medicine paper: "Longer hospital stays and higher costs associated with HAI cases may, in part, be due to extended preinfection hospital exposure. Because extended LOS is an independent risk factor for infection, the preinfection LOS of patients with HAIs may be expected to exceed that of similar patients who did not acquire an HAI. Attributing preinfection LOS to HAIs would overstate the true costs of HAIs...A study of 490 nosocomial sepsis cases from 8 tertiary care centers found that the mean preonset LOS was approximately 40% of the total LOS for these hospitalizations."
To quote from the PA reports methods: "The average payment reported is for the entire length of stay, and not just for the treatment related to the infection." It's like they are FLAUNTING THEIR ERROR. When the reports states "the estimated average Medicare fee-for-service payment for hospital stays for patients who acquired an HAI was $21,378...(and) the estimated average Medicare fee-for-service payment for those without an HAI was $6,709", we know we can't trust the estimates. In fact, if we can't trust those, why should we trust any of it?
My copy just went into the trash.