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Melasma Area & Severity Index (MASI) - Scientific Formula

Dermatology Equation

Standard Calibration Equation:

MASI = 0.3(D+H)A_forehead + 0.3(D+H)A_r_cheek + 0.3(D+H)A_l_cheek + 0.1(D+H)A_chin

Accuracy Bounds & Limits:

While mathematical calculators evaluate demographic models, extreme variance (hyperthyroidism, dialysis cases, muscular bodybuilders, pregnancy) can trigger output errors. Weight and clearance assessments must follow separate personalized titration grids.