Meltzer C, et al. - Researchers conducted this retrospective cohort study to model the association volume-outcomes as a continuous function and identify the point where the increasing volume of surgeons begins to yield better results. This investigation was performed on 10,546 patients from two Kaiser Permanente regions (Northern and Southern California) in 2018 to 2019, who had total thyroidectomy from January 1, 2008, through December 31, 2015, and were followed up through December 31, 2017. The sample consisted of 10,546 patients (aged 45 to 64 years). A generalized additive model showed that occurrence rates of paralysis of the vocal cord and hypoparathyroidism started to decline at an annual surgeon procedure volume of 18 thyroidectomies. A generalized linear mixed-effects model demonstrated that small but statistically significant reductions in complication rates were linked to an increase in the annual volume. In systems with low baseline complication rates, shifting patients to higher-volume surgeons to realize these reductions can be of variable attractiveness.