@misc{9684,
  author = {E. Herrett and S. Thomas and L. Smeeth},
  title = {Validity of diagnoses in the general practice research database},
  year = {2011},
  journal = {Br J Gen Pract},
  volume = {61},
  number = {588},
  pages = {438-9},
  issn = {0960-1643},
  doi = {10.3399/bjgp11X583092},
}