...The report found similar results regarding orientation services, which include providing students with information on navigating the library and finding support services such as academic and mental-health counseling. Previous research shows that participation in orientation leads to greater use of support services and improved retention of at-risk students, the report says. However, among colleges that offer orientation programs, only 38 percent report that they require it for all first-time students.
From The Chronicle of Higher Education, February 2, 2012, Multiyear Study of Community-College Practices Asks: What Helps Students Graduate?, Jennifer Gonzalez.
David Binder reports in the comments that "The study discussed in the article ("A Matter of Degrees: Promising Practices for Community College Student Success") is the first of an intended 3 study series and is available at http://www.ccsse.org/. It can be downloaded as an Adobe Acrobat file."