@misc{indiciae3cd96085fe58,
  title = {What is a retrospective study?},
  author = {P Bergsjø},
  year = {1983},
  doi = {10.1016/0002-9378(83)90945-6},
  url = {https://pubmed.ncbi.nlm.nih.gov/6846418/},
  note = {Source identifier: 6846418}
}