Joel Katz
Joel Katz is a pain researcher and the second author on Redelmeier, Katz and Kahneman (2003), the randomised colonoscopy trial in Pain. Six hundred and eighty-two patients took part, half of them randomly assigned to have a short, gentler interval added to the end of the procedure. He is routinely dropped when the study is cited, which is usually given as Redelmeier and Kahneman, or simply as Kahneman.
Who they are
Nothing beyond his authorship on this paper has been verified here, and no affiliation is claimed. This page is short because the vault is honest about what it checked. Naming him is the point of it.
The trial itself measured pain during the procedure on a ten-point scale and memory afterwards by both rating and ranking, then followed up on whether patients came back for a repeat procedure.
Key papers
Redelmeier, D. A., Katz, J., & Kahneman, D. (2003). "Memories of colonoscopy: a randomized trial", Pain, 104(1 to 2), 187 to 194. Second author. 682 patients, randomised.
Key ideas
This is the only study in this literature that measured a behaviour rather than a rating, and the behaviour barely moved. Patients remembered the gentler ending more kindly. Not many more of them came back because of it.
That gap between what people remember and what they then do is the most important limit on the whole peak-end story, and it comes from this trial.
Three-author papers routinely lose their middle author when they are retold. Naming him is a small correction and a cheap one.
Concepts on this site
The Experiencing Self and the Remembering Self
Sources
- Redelmeier, D. A., Katz, J., & Kahneman, D. (2003). Pain, 104(1 to 2), 187 to 194.
- Vault research and verification pass, 2026-09-11. No affiliation checked, so none is stated.