@misc{indiciaeb51ffa0142b5,
  title = {Observational epidemiological studies: values and limitations.},
  author = {François Gueyffier},
  year = {2003},
  doi = {10.1097/00004872-200304000-00004},
  url = {https://pubmed.ncbi.nlm.nih.gov/12658007/},
  note = {Source identifier: 12658007}
}