@misc{indiciaef23e3634a5a2,
  title = {Developing improved observational methods for evaluating therapeutic effectiveness.},
  author = {R I Horwitz and C M Viscoli and J D Clemens and R T Sadock},
  year = {1990},
  doi = {10.1016/0002-9343(90)90182-d},
  url = {https://pubmed.ncbi.nlm.nih.gov/1978566/},
  note = {Source identifier: 1978566}
}