Index case

The index case or patient zero is the first documented patient in a disease epidemic within a population,[1] or the first documented patient included in an epidemiological study.[2] It can also refer to the first case of a condition or syndrome (not necessarily contagious) to be described in the medical literature, whether or not the patient is thought to be the first person affected.[citation needed] An index case can achieve the status of a "classic" case study in the literature, as did Phineas Gage, the first known person to exhibit a definitive personality change as a result of a brain injury.[3]

  1. ^ "Diseases – Activity 1 – Glossary, page 3 of 5". science.education.nih.gov. Archived from the original on 10 November 2017. Retrieved 10 November 2017.
  2. ^ "WordNet Search – 3.0". Princeton University, wordnetweb.princeton.edu. Archived from the original on 3 March 2012. Retrieved 3 November 2010.
  3. ^ "Why Brain Scientists Are Still Obsessed With The Curious Case Of Phineas Gage". NPR.org. Archived from the original on 28 August 2019. Retrieved 18 November 2017.