@misc{indiciaec76f593c8835,
  title = {Beyond randomised versus observational studies.},
  author = {John Concato and Ralph I Horwitz},
  year = {2004},
  doi = {10.1016/s0140-6736(04)16285-5},
  url = {https://pubmed.ncbi.nlm.nih.gov/15158623/},
  note = {Source identifier: 15158623}
}