The following is a summary of “79 is the new 70: Left digit bias in craniotomy,” published in the December 2022 issue of Surgery by Blumenfeld, et al

Left digit bias is a psychological condition where the first digit’s value causes the difference between values to be seen as being bigger. An 80-year-old person, for instance, may be considered to be substantially older than a 79-year-old. For a study, researchers sought to find out if older individuals with severe brain damage who had craniotomies exhibited a left digit preference.

Patients from the National Trauma Data Bank who were 69, 70, 79, and 80 years old and had traumatic brain injuries with an abbreviated injury scale severity of at least 3 were included. Included were 38,908 patients. The percentage of patients having a craniotomy was compared using a Chi-squared Test.

The rate of craniotomies was greater in 79-year-olds than in 80-year-olds (7.8% vs. 6.4%, P< 0.001). The rate of craniotomies was the same in those aged 69 and 70 (8.2% vs 7.8%, P = 0.2622);

The study revealed that individuals with traumatic brain injury who were 79 vs. 80 years old were more likely to have left digit bias in the choice to do a craniotomy.

Reference: americanjournalofsurgery.com/article/S0002-9610(22)00638-9/fulltext