The Office of Inspector General (OIG) of the U.S. Department of Health and Human Services (HHS) has released this report, which shows the results from a recent study that was aimed at determining if VFC providers are meeting their vaccine management requirements, including the storing of vaccines at proper temperature ranges and handling expired vaccines in an appropriate manner.
http://oig.hhs.gov/oei/reports/oei-04-10-00430.pdf