Are Left-Handers Worse Surgeons Than Right-Handers?

About 10.6% of people are left-handers, while the remaining 89.4% are right-handed. While left-handedness does not have any impact on performance in most jobs, patients sometimes worry that left-handed doctors may be worse at performing surgeries than right-handed doctors. The reasoning behind this idea is that surgical training will be largely targeted at right-handers since most medical trainees are right-handed. Also, most professors teaching surgery at universities will be right-handed. Moreover, some surgical instruments, like scissors, may be produced for right-handed doctors, and thus be harder to handle for left-handed doctors. However, so far there has been no systematic scientific study on whether left-handed surgeons actually are worse (or maybe even better!) than right-handed surgeons.

A new study on how left-handedness affects performance when doing surgery

A new study, just published in the scientific journal “Surgery Open Science”, was aimed at filling this gap in the scientific literature on left-handedness (Bitar and co-workers, 2025). The research team, headed by scientist Elio R. Bitar from the American University of Beirut Medical Center in Lebanon, tested whether handedness affected the ability to perform surgery. To this end, they recruited a group of volunteers who were in medical training, such as first and second-year medical students and nursing students. By choosing to test volunteers at the beginning of their medical career, the scientists avoided the effects of differences in how often a doctor performed surgery before on their data. Overall, 129 volunteers (86 right-handers and 43 left-handers) agreed to participate in the study.

The volunteers first had to participate in a training session in which they learned simple interrupted suturing, a simple surgical technique. Afterward, they had to perform three simple interrupted sutures on a silicone training pad using the same surgical instruments used in the training. Their performance was then rated by the scientists using a standard 10-item checklist for surgical performance. Volunteers could get between 0 and 100 points for how well they performed the surgery. Moreover, the volunteers answered a questionnaire about how helpful they perceived the training and how comfortable they were to conduct the surgery after the training.

What did the scientists find out?

The analysis of the performance data showed that all volunteers were able to successfully perform the trained surgery on the silicone training pad. Overall, left-handed volunteers had slightly higher performance scores (around 93 out of 100) than right-handed volunteers (around 88 out of 100), but the difference narrowly missed statistical significance. Thus, the results of the study show that there were no differences between left-handers and right-handers regarding their performance when conducting surgery. The questionnaire data revealed that left-handed volunteers found it challenging to use surgical instruments that were produced for right-handers, but apparently, this had no negative impact on the performance.

Thus, taken together, no patient who will undergo surgery has to be afraid if their surgeon is left-handed – they are in good hands!