Negative study: no association of XMRV with prostate cancer or CFS in Japan

[Jemal]

Retrovirology has published a new negative study:

http://www.retrovirology.com/content/8/1/20

 

[toddm1960]

However, the lack of adequate human specimens as a positive control in Ab screening and the limited sample size do not allow us to draw a firm conclusion


How did this get published?

First they had no know positive sample, so they can't even confirm they could find the virus if it was there.
Second their sample size was too small to draw a true concusion.

All that will hit the media is "another negitive study" This looks just like the 1991 playbook.

 

[omerbasket]

No association of XMRV with prostate cancer in Japan?
http://www.jurology.com/article/S0022-5347(11)01208-0/fulltext
Think again.

I appreciate them not doing of their crappy study what others did of theirs, but why publish a crappy study and not just do it right, when there are many samples that are at least thought by the XMRV-supporters to be positive, and you can use them?

 

[ixchelkali]

First they had no know positive sample, so they can't even confirm they could find the virus if it was there.
Second their sample size was too small to draw a true concusion.

Actually, this looked like a fairly thoughtfully designed study to me. When they said that they had no known positive sample, I believe they were saying that there is no validated XMRV test yet, so NO ONE has a definite positive sample.

We are unable to determine whether the anti-Gag CA Abs we identified would indicate XMRV infection or not, until panel plasma or serum samples collected from human subjects definitely infected with XMRV become available

They acknowlege that as a limitation of antibody testing at this time, but then they go on to describe what they did to try to overcome that shortcoming.

I'm glad that someone is trying to find XMRV using antibody testing, even given that limitation. If they had found XMRV in their samples, they would probably have had to defend the validity of their test, but it would have gone a long way to negate the contamination theories. They did find signs of XMRV, just not in high amounts and not more prevalent in prostate cancer and ME/CFS patients than controls.

They could have done a better job of characterizing their ME/CFS patient cohort. All we really know is that they met the Fukuda criteria and were patients of the Osaka Fatigue Center. But at least they described how the samples were handled.

I wish I knew enough to have an informed opinion about the design of their antibody test, but I don't. I hope we can get a good impartial analysis from someone who does.

I don't think we should assume that every negative study is automatically badly designed. Sure, the early ones to get published were just shoddy. They didn't tell us anything, because they WERE poorly designed. But a well designed negative study advances the science as much as a well designed positive one does. They all fit more pieces into the puzzle. That's what we need.

I hope XMRV pans out. Besides giving us a known etiology and biomarker, it would lead to treatments. I'm not giving up that hope. But I want science to give us the truth, whatever it is. Junk studies posing as science won't give us that, but well-designed studies will (eventually), even if they're negative. As long as the funding doesn't dry up, and as long as the researchers keep looking.​

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