We are trying to define the outcome criteria of new Japanese legislation of forensic mental health. For this purpose we plan to apply the Delphi Method. However I have no experience of the research using it.
Delphi was created by RAND and has been improved over the years. The only challenge with Delphi is that it tends to coalesce around experts and sometimes the insights on the margins that would be helpful are washed out.
Ted Gordon is a pioneed in Delphi and also has done much work to improve the process. A useful paper is at http://personales.alumno.upv.es/~cargupe/docs/delphi/5-delphi.pdf. I tried to attach a copy and it did not work. If you cannot retrieve the paper at the link, send me your email and I will send you a copy.
Great. And Antonio's references are wonderful. Hal Linstone has done great work, but I must confess that I did not know of his work in Delphi. Shame on me.
The Delphi method has been extensively used in Japan, by NISTEP (since the 70's). You can learn about the method in their reports. The 9-th report can be found here: http://www.nistep.go.jp/achiev/l_all-e.html#NR (see reports 140-142)