Multicentre trials should evaluate multiplex panels and cross-matrix performance (GCF and saliva) using AUC, calibration, and net-benefit analyses against clinical improvement, with comparative analyses performed by phenotype (CP vs. AgP; staged/graded categories) and by systemic modifiers (e.g., T2DM) to strengthen generalisability [18,35,60]. The gene discussed is ATP5MK; the disease is type 2 diabetes mellitus.