[Correlation analysis between serum free testosterone and total testosterone in Chengdu females]

This paper is aimed to analyze the correlation between serum free testosterone (FT) and total testosterone (TT) to acquire a cutoff about using total testosterone to diagnose hyperandrogenism in Chengdu females. We investigated 1854 women by cluster sampling method, detected their serum FT levels and TT levels, scored relative items, analyzed the correlation and made the ROC curve to get a cutoff of TT levels. Serum FT had a linear correlation with serum TT (r = 0.597, r2 = 0.356, P < 0.001). The cutoff value was 0.635 ng/mL. The specificity and sensitivity were 76.3% and 77.24%, respectively. No correlation found between serum FT and Ferriman-Gallway Score (P = 0.392). Positive correlations were seen between serum FT and Plewig-Kligman Score (r = 0.137, P < 0.001), serum TT and Ferriman-Gallway Score (r = 0.069, P = 0.003) and serum TT and Plewig-Kligman Score (r = 0.092, P < 0.001). There is a linear correlation between serum FT and TT. We can diagnose hyperandrogenism according to the serum TT cutoff value (0.635 ng/mL). Its clinical symptoms are not paralleled with the biochemical test results.