@misc{9751,
  author = {E. Herrett and S. Thomas and W. Schoonen and L. Smeeth and A. Hall},
  title = {Validation and validity of diagnoses in the General Practice Research Database: a systematic review},
  year = {2010},
  journal = {Br J Clin Pharmacol},
  volume = {69},
  number = {1},
  pages = {4-14},
  issn = {0306-5251},
  doi = {10.1111/j.1365-2125.2009.03537.x},
}