Study subject to unmeasured confounders and biases

BMJ. 2011 May 31:342:d3349. doi: 10.1136/bmj.d3349.
No abstract available

Publication types

  • Letter
  • Comment

MeSH terms

  • Androstenes / adverse effects*
  • Contraceptives, Oral, Combined / adverse effects*
  • Female
  • Humans
  • Levonorgestrel / adverse effects*
  • Venous Thromboembolism / chemically induced*

Substances

  • Androstenes
  • Contraceptives, Oral, Combined
  • Levonorgestrel