Robert Whitaker writes in “Mad in America” in the preface (XIII-XIV):

“I bumped into several studies in the medical literature, that really struck me as odd. Over the past twenty-five years, outcomes for people in the United States with schizophrenia have worsened. They are now no better than they were in the first decades of the twentieth century, when the therapy of the days was to wrap the insane in wet sheets. Even more perplexing, schizophrenia outcomes in the United States and other developed countries today are much worse than in the poor countries of the world. The World Health Organization has looked at this question repeatedly – initially, nobody could believe this disparity in outcomes – and each time it has come back with the same result. Suffer a psychotic break in a poor country like India and Nigeria, and chances are that in a couple of years you will do fairly well. But suffer a similar break in the United States or other developed countries and it is likely that you will become chronically ill.”

 
The studies Robert Whitaker cites are on the web at http://psychrights.org/Research/Digest/Chronicity/NeurolepticResearch.htm, including the two WHO studies. 

There are also many other studies organized by topic at http://psychrights.org/Research/Digest/Researchbytopic.htm.