"I know this sounds applicable: Even when a claim is disproved, it hangs around like a deadbeat renter you can't evict. Years after the claim that vitamin E prevents heart disease had been overturned, half the scientific papers mentioning it cast it as true, Ioannidis found in 2007."
The main reason is they are still quoting the results from papers that attribute Vit E to heart health.
There are just too many papers for a researcher to read and some just miss the latest results. I wonder how many papers Ioannidis actually read??
Okay I thought I would go down this side street. Gee it is a bit funny once you really start to dig.
Some extracts from that paper:
Ioannidis, John. 2005 Why Most Published Research Findings Are False. PLoS Med. 2005 August; 2(8): e124. Published online 2005 August 30. doi: 10.1371/journal.pmed.0020124.
Modeling the Framework for False Positive Findings:
"Several methodologists have pointed out [9?11] that the high rate of nonreplication (lack of confirmation) of research discoveries is a consequence of the convenient, yet ill-founded strategy of claiming conclusive research findings solely on the basis of a single study assessed by formal statistical significance...."
9 Sterne JA, Davey Smith G. Sifting the evidence?What's wrong with significance tests. BMJ. 2001;322:226?231. [PMC free article] [PubMed]
10 Wacholder S, Chanock S, Garcia-Closas M, Elghormli L, Rothman N. Assessing the probability that a positive report is false: An approach for molecular epidemiology studies. J Natl Cancer Inst. 2004;96:434?442. [PubMed]
11 Risch NJ. Searching for genetic determinants in the new millennium. Nature. 2000;405:847?856. [PubMed] ---------------
Testing by Several Independent Teams:
"Several independent teams may be addressing the same sets of research questions. As research efforts are globalized, it is practically the rule that several research teams, often dozens of them, may probe the same or similar questions. Unfortunately, in some areas, the prevailing mentality until now has been to focus on isolated discoveries by single teams and interpret research experiments in isolation. An increasing number of questions have at least one study claiming a research finding, and this receives unilateral attention."
An interesting blog on the issues of research and results:
