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Screening Benefit, Evaluation of

  1. Philip C. Prorok

Published Online: 15 JUL 2005

DOI: 10.1002/0470011815.b2a04046

Encyclopedia of Biostatistics

Encyclopedia of Biostatistics

How to Cite

Prorok, P. C. 2005. Screening Benefit, Evaluation of. Encyclopedia of Biostatistics. 7.

Author Information

  1. National Institutes of Health, Bethesda, MD, USA

Publication History

  1. Published Online: 15 JUL 2005


Screening is the testing of apparently healthy individuals from a population for the purpose of separating them into groups with high and low probabilities of having a given disease such as cancer. This article examines various issues encountered in assessing the benefit of screening. The use of observational studies and possible involvement of selection bias is included, together with a discussion of lead time and length bias. Appropriate study endpoints are discussed. Various possibilities for randomized control trials are reviewed, and the use of observational designs to compare cancer incidence and mortality in a population before and after the introduction of a screening program is mentioned. The entry also lists important information requirements for the evaluation of screening programs.


  • study design;
  • observational studies;
  • clinical trials;
  • bias;
  • data requirements