Fig. 3

Adjusted Smoothed Curve Analysis Revealing the Interplay Between TG and Lumbar BMD: GAM identified a threshold non-linear correlation between TG and lumbar BMD in OPFs. The upper and bottom curves depict the extent of the 95% confidence interval, whereas the middle curve illustrates the link between TG and lumbar BMD. The models were adjusted for covariate variables. The middle curve exhibited a point of inflection (K) at positions 1.26.