Brain Blogger has a primer here.
It's based on this article:
Kaczorowski, M. (2002). Ice cream evoked headaches (ICE-H) study: randomised trial of accelerated versus cautious ice cream eating regimen. BMJ, 325(7378), 1445-1446. DOI: 10.1136/bmj.325.7378.1445
Sigh. I must be in the wrong field. Not much ice cream related research in philosophy.