@misc{8939,
  author = {S. Price and S. Stapley and E. Shephard and K. Barraclough and W. Hamilton},
  title = {Is omission of free text records a possible source of data loss and bias in Clinical Practice Research Datalink studies? A case-control study},
  year = {2016},
  journal = {BMJ Open},
  volume = {6},
  number = {5},
  pages = {e011664},
  issn = {2044-6055},
  doi = {10.1136/bmjopen-2016-011664},
}