Novel thyroidectomy difficulty scale correlates with operative times

Background: The aim of this study was to evaluate a new thyroidectomy difficulty scale (TDS) for its inter-rater agreement, correspondence with operative times, and correlation with complications. Methods: We developed a four item, 20-point TDS. Following cases where two board-certified surgeons participated, each surgeon completed a TDS, blinded to the other's responses. Paired sets of TDS scores were compared. The relationship between operative time and TDS scores was analyzed with linear regression. Multiple regression evaluated the association of TDS scores and other clinical data with operative times. Results: A total of 119 patients were scored using TDS. In this cohort, 22.7 % suffered from hyperthyroidism, 37.8 % experienced compressive symptoms, and 58.8 % had cancer. The median total TDS score was 8, and both surgeons' total scores exhibited a high degree of correlation. Overall, 87.4 % of the two raters' total scores were within one point of each other. Patients with hyperthyroidism received higher median scores than euthyroid patients (10 vs. 8, p < 0.01). Similarly, patients who suffered a complication had higher scores than those without complications (10 vs. 8, p = 0.04). TDS scores demonstrated a linear relation with operative times (R² = 0.36, p < 0.01). Cases with a score of ≥14 took 41.0 % longer compared to cases with scores of ≤5 (p < 0.01). In the multiple regression analysis, TDS scores independently predicted the operative time (p < 0.01). Conclusion: The TDS is an accurate tool whose scores correlate with more difficult thyroidectomies as measured by complications and operative times.