Does Surgeon Level of Expertise Correlate with Patient Outcomes?

It is difficult to evaluate the results of surgical techniques as there is inherent variability between surgeons in regard to experience, skill level, and knowledge. Tang suggested a classification system in 2009 in an attempt to standardize surgeon level of expertise, with categories ranging from nonspecialist (Level I) to expert (Level V). This epidemiological analysis of all articles citing Tang's original paper examines if a surgeon's self-reported level of expertise correlates with outcomes and evaluates whether the current definition of Tang level is sufficient to account for expertise bias.  In May 2021, all articles citing Tang level of expertise were identified (  = 222). Articles were included if they described a novel technique and provided author(s)' levels (  = 205). Statistical analysis was conducted, and -values less than 0.05 were considered significant.  The most common specialties reporting Tang level of expertise were orthopaedic surgery (82.9%) and plastic surgery (15.5%). The most common subspecialty was hand surgery. 2020 was the year with the most studies reporting level of expertise (31.7%), followed by 2021 (20.0%) and 2019 (17.1%). The majority of studies (80.5%) reported positive results with their technique, and of these, 63.3% were statistically significant. Level of expertise was not significantly associated with a doctoral degree, type of residency completed, fellowship completion, hand fellowship, author sex, study type, or result significance.  The current Tang classification is both underreported and incomplete in its present state. To account for expertise bias, we recommend all authors report Tang level when describing surgical techniques. Studies with multiple authors should explicitly state the level of each author, as well as a weighted average accounting for the total contribution of each individual.