That is the title of a study I have done, and the preliminary results appear in a paper
embedded below I have posted online [links appear at the end of the post]. The document is labeled Version 1.0, since study is yet to be wrapped up. Still, there's enough in there for it to be opened up for comments / suggestions.
I presented this work at the Workshop on Academic Ethics organized by Rahul Siddharthan, Gautam Menon and N.S. Siddharthan about a month ago.
Quick summary: PubMed database lists ~103,000 papers published by Indian authors during the previous decade (2001-2010);
70 69 of these papers have been retracted, and 45 of the retractions are due to some form of misconduct. Plagiarism is overwhelmingly the primary mode of misconduct: all but one of the 45 misconduct-related retractions were due to plagiarism.
If that doesn't sound bad enough, consider this: At 44 per 100,000 papers, India's misconduct rate is far higher than that of countries such as the UK, the USA, Germany and Japan.
There's some silver lining, though: Retraction of papers from Indian authors show a steep fall since 2007 -- either because Indian researchers know better now, or because plagiarized papers are ever less likely to make it to print in the first place due to increasingly widespread use of plagiarism detecting software by journals.
* * *
Update (13 August 2011): The html version will keep getting updated with minor corrections which will be duly noted in the footnotes. There has already been one correction: the number of retractions of Indian papers for the decade 2001-10 is 69 -- the original version had it at 70.