Mike the Mad Biologist

Since I’m going on vacation, I might not get to it right away, but the NY Times has a good article about two studies that appear to contradict each other about various effects to control hospital-associated MRSA infections.

I haven’t given the two article an in-depth reading yet, but it seems to me that the article which showed no effect seemed to have much higher baseline rates of infection (I’m comparing the infection/1000 patient days in the ICU).


Also, it seems that without knowing the strains of MRSA involved, one could legitimately get different answers.


  1. #1 Confounding
    April 15, 2011

    Reading the two articles quickly, they appear to be asking fundamentally different questions – which tends to be the answer when “Why does this observational study and an RCT not have the same results?”

    The VA study is a basket of interventions, the other a single one – and honestly, having read the RCT, I think it was the intervention itself that failed. The enhanced isolation procedure was still fairly worrisomely infrequent – if there’s a high enough probability per contact of MRSA transmission, the rate of unprotected contacts in the intervention group is probably enough to punch right through the slightly upgraded contact precautions.

    To draw an analogy to another disease, using a condom 75% of the time won’t keep you from contracting an STI, but it’s not the condom that failed. With the VA study, given the whole package of interventions, including some “culture” based interventions, there may be a higher compliance rate.

    That’s just my utterly unfounded conjecture, without being able to see the data, and the VA not reporting their compliance rates.