(6) In this study, we ensured the robustness of the results through a series of sensitivity analyses (conversion of target-independent variable form, subgroup analysis, using a GAM to insert the continuity covariate into the equation as a curve, calculating E-values to explore the potential for unmeasured confounding, and reanalyzing the association between eGFR and NAFLD on individuals with complete data, or after excluding participants FPG > 6.1 mmol/L, ALT > 40 U/L, eGFR < 60 mL/min/1.73 m2, and TG ≥ 1.7 mmol/L). Here, GPT is linked to metabolic dysfunction-associated steatotic liver disease.