According to the latest The Go-To Global Think Tanks 2009 ranking report*, PolicyFile covers all of the:
In PolicyFile, professionals find information on both sides of a public policy debate. They get immediate access to over 386 think tanks, research organizations, and advocacy groups including the Hoover Institution, International Monetary Fund, Organization for Economic Cooperation and Development, RAND Corporation, and the World Bank.
Indexes, abstracts, and links directly to current research on virtually every public policy issue--domestic and international are provided. The database has over 106,000 records and is updated weekly, with more than 50 percent of the abstracts linking directly to the full text of research reports and studies.
* From the University of Pennsylvania’s Think Tanks and Civil Societies Program. The report also ranked the Top 25 global think tanks, and PolicyFile covers 22 of these.