If you have ANY interest in the rigourous analysis of big name clinical trials PLEASE read more…
Game changing paper
Many of you will have read and discussed the landmark paper that was published in the New England Journal of Medicine in June this year
Here is the abstract, but I hope you will have all seen the full text and maybe the accompanying supplementary appendix.
It was a big (74,256 patients), pragmatic, cluster-randomized trial, and on the surface the results look impressive:
By using twice-daily intranasal mupirocin for 5 days and daily bathing with chlorhexidine-impregnated cloths for the entire ICU stay, they state:
“A total of 181 patients would need to undergo decolonization to prevent one MRSA-positive clinical culture”
“54 patients would need to undergo decolonization to prevent one bloodstream infection from any pathogen”
Implications
This kind of intervention, that appears to reduce MRSA infections and any kind of bloodstream infection, could change practice around the world.
There are immense implications from this, including:
- Cost of the intervention
- Increased microbial chlorhexadine resistance
- More anaphylaxis from chlorhexadine, which is increasing in prevalence already
The Question
ARE THE STATS CORRECT?
We were hashing this out in our journal club, but could not get the stats to add up.
If you can PLEASE COMMENT HERE!
The NNT’s of 54 and 181 seem impossibly small, with huge clinical implications.
Please try it yourself; look at Table 3. Frequency and Rates of Outcomes during the Baseline and Intervention Periods, According to Study Group
With bloodstream infection from any pathogen, the Group 1 (standard care) number of events per 1000 patient days is 4.1. With Group 3, the number of events is 3.6 per 1000 patients days. Even taking change from baseline into account and assuming these NNTs have been calcuated AFTER randomization, between Group 1 and Group 3, we get nowhere close to their NNT’s.
PLEASE have a go and see if you can match their NNT’s.
IF you can’t there is a serious problem, with practice changing implications.
It’s too late to write letters to the NEJM, so a robust discussion in a peer reviewed forum seems a good way to go.
Thank you to Gordon Doig for stimulating this important discussion.
GET INVOLVED!
