Official "Science News" Thread

[ewmayer]

LOL@ "triple blind study".

[jasong]

Originally Posted by ewmayer

LOL@ "triple blind study".

Does triple blind mean no one will know until someone finds the key to that cabinet? (asking in ignorance since I've never fully understood the "-blind" language)

[Batalov]

http://en.wikipedia.org/wiki/Blind_e...e-blind_trials

[science_man_88]

Originally Posted by ewmayer

LOL@ "triple blind study".

taking a quote from the wikipedia linked to by Batalov:

A triple-blind study is an extension of the double-blind design; the committee monitoring response variables is not told the identity of the groups. The committee is simply given data for groups A and B. A triple-blind study has the theoretical advantage of allowing the monitoring committee to evaluate the response variable results more objectively. This assumes that appraisal of efficacy and harm, as well as requests for special analyses, may be biased if group identity is known. However, in a trial where the monitoring committee has an ethical responsibility to ensure participant safety, such a design may be counterproductive since in this case monitoring is often guided by the constellation of trends and their directions. In addition, by the time many monitoring committees receive data, often any emergency situation has long passed.[6]

[only_human]

Originally Posted by jasong

Does triple blind mean no one will know until someone finds the key to that cabinet? (asking in ignorance since I've never fully understood the "-blind" language)

Originally Posted by Batalov

http://en.wikipedia.org/wiki/Blind_e...e-blind_trials

Although this Wikipedia article mentions a true triple blind methodology, the triple blind is a bit of a joke in the twitter comment. The lost key could rather be any key to a form of meaningful access including decryption or indexing or interpretation. The joke is the unintentional additional blinding.

A related example of why the researcher or observer should be blinded is this example:
http://en.wikipedia.org/wiki/Clever_Hans

Clever Hans (in German, der Kluge Hans) was an Orlov Trotter horse that was claimed to have been able to perform arithmetic and other intellectual tasks.

After a formal investigation in 1907, psychologist Oskar Pfungst demonstrated that the horse was not actually performing these mental tasks, but was watching the reaction of his human observers. Pfungst discovered this artifact in the research methodology, wherein the horse was responding directly to involuntary cues in the body language of the human trainer, who had the faculties to solve each problem. The trainer was entirely unaware that he was providing such cues. In honour of Pfungst's study, the anomalous artifact has since been referred to as the Clever Hans effect and has continued to be important knowledge in the observer-expectancy effect and later studies in animal cognition.

The Amazing Randi once was in the embarrassing position of explaining blinding to sincere Russian psychic researchers (although I could not find the a reference to this just now)

[Batalov]

Well, the irony, if spelled-out, is that in a proper triple-blind study someone still knows the affected and control individuals. In the twitter quote, the key translation table was lost entirely.

I've just returned from a conference where one of the significant themes was the personalized medicine. In some important areas, the future (the personalized treatments) is already here, particularly in cancer. In other areas, it is far away and there's still a huge lot to be learned. A very important resource for many academic researchers is the access to EMR (electronic medical records), but ethic and privacy concerns are firmly in a way of anyone who would like to mine this data. That is why there are centralized repositories that de-identify ("blind") vast data sets of real patients' data. So, as a researcher, you can study the genetic associations of patients' genotypes to their clinical presentations (their symptoms, measurements of their indicators - e.g. glucose or insulin levels, blood pressures, time to relapses of disease etc) - but you will not know who they were, and you are not allowed to treat* (in huge majority of cases one wouldn't know how to treat just yet, anyway). It is a hugely important field of study. The twitter quote is maybe a slip of the tongue fingers, or maybe a sardonic joke (meaning that the study 3a is now wasted).

Have a look at the completely serious arena for academic competition for best methods of genomic predictions here (dubbed CAGI).


{while previewing the post, I note that this is already a crosspost. That's fine. This is an endless topic for a discussion. And for some people, - a full-time job. :wink-wink: }

__________
* in the spirit of the twitter story, I can also share that we once sequenced the set of tuberculosis samples from living, yet completely anonymous donors. For one of them, we found that the sequence belonged not to M.tuberculosis but M.abscessus... long story short, we had no right to feed back to the treatment, but because this was so highly unusual (and the patient was obviously treated for a wrong infection), that we did in fact provide feedback (to the third party that held the keys), and we hope that this was passed to the participating hospital and that the treatment was changed, but we will never know.

[Dubslow]

Holy -blam!- !!

Largest structure in universe discovered — it's mind-boggling
Large quasar group stretches 4 billion light-years

Astronomers have discovered the largest known structure in the universe, a clump of active galactic cores that stretches 4 billion light-years from end to end.

The structure is a large quasar group (LQG), a collection of extremely luminous galactic nuclei powered by supermassive central black holes. This particular group is so large that it challenges modern cosmological theory, researchers said.

"While it is difficult to fathom the scale of this LQG, we can say quite definitely it is the largest structure ever seen in the entire universe," lead author Roger Clowes, of the University of Central Lancashire in England, said in a statement. "This is hugely exciting, not least because it runs counter to our current understanding of the scale of the universe."

Quasars are the brightest objects in the universe. For decades, astronomers have known that they tend to assemble in huge groups, some of which are more than 600 million light-years wide.

But the record-breaking quasar group, which Clowes and his team spotted in data gathered by the Sloan Digital Sky Survey, is on another scale altogether. The newfound LQC is composed of 73 quasars and spans about 1.6 billion light-years in most directions, though it is 4 billion light-years across at its widest point.

[science_man_88]

Largest structure in universe discovered

Astronomers have discovered the largest known structure in the universe, a clump of active galactic cores that stretches 4 billion light-years from end to end.

[davar55]

Originally Posted by science_man_88

Largest structure in universe discovered

I didn't see a mention of how far away this is.

[science_man_88]

Originally Posted by davar55

I didn't see a mention of how far away this is.

I also apparently didn't see that dubslow beat me to it. to not wrap completely around to form a circle 4 billion light years wide suggest above 1.27 billion light years distant.

[cheesehead]

Originally Posted by davar55

I didn't see a mention of how far away this is.

A couple of clicks gets you to http://phys.org/news/2013-01-astrono...-universe.html where the article has a chart from which you can estimate the apparent angular size.

Looks like about 1/4-1/3 radian to me.