@misc{indiciaeac5f0afdb24a,
  title = {Executive summary? All about validating scales and stages.},
  author = {Isolde den Tonkelaar and Frank J Broekmans and Evelien J de Boer and Egbert R te Velde},
  year = {2002},
  doi = {10.1016/s0015-0282(02)04220-6},
  url = {https://pubmed.ncbi.nlm.nih.gov/12414009/},
  note = {Source identifier: 12414009}
}