Figure 3: Calibration curve of the nomogram for success rate prediction model. The x-axis represents the predicted success rate of Micro-TESE. The y-axis represents the actual successful sperm retrieval (SSR) by Micro-TESE. The diagonal dotted line represents a perfect prediction by an ideal model. The solid line represents the performance of the nomogram, of which a closer fit to the diagonal dotted line represents a better prediction. C-statistics for calibration curve is 0.907 (95% CI: 0.879–0.928). CI: confidence interval; Micro-TESE: microdissection testicular sperm extraction.