@misc{indiciaea4e4c523f290,
  title = {Prospective or retrospective?},
  author = {A Keys},
  year = {1991},
  doi = {10.1136/bmj.302.6781.909-b},
  url = {https://pubmed.ncbi.nlm.nih.gov/2025739/},
  note = {Source identifier: 2025739}
}