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ISI (Insomnia Severity Index) - Scientific Formula

Neurology & Psychiatry Equation

Standard Calibration Equation:

Score = Sum of 5 high-yield symptom severity ratings (0 to 4 each)

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.