Online Tool

FEES Dysphagia Index

Compute FDI-S (Safety), FDI-E (Efficiency), and FDI-C (Composite) from PAS and Yale Pharyngeal Residue ratings. Enter scores only for consistencies that were tested.

FEES Findings

Consistency PAS (1–8) Yale Vall. (1–5) Yale Pir. (1–5)
FDI-S (Safety)
–
0 = worst, 100 = no impairment
FDI-E (Efficiency)
–
0 = worst, 100 = no impairment
FDI-C (Composite)
–
(FDI-S + FDI-E) / 2
Formulas:
FDI-S = (1 − (mean PAS − 1) / 7) × 100
FDI-E = (1 − (mean Yalecombined − 1) / 4) × 100 where Yalecombined = mean of valleculae and pyriform sinus scores per consistency.
FDI-C = (FDI-S + FDI-E) / 2

Orientation values derived from Werner et al., J Neurol 273:359 (2026), N = 2,943. FOIS mapping based on mean FDI-C per FOIS level (Cohort 2, n = 1,545). Mortality zones based on restricted cubic spline analysis (n = 1,557, 65 events).
Research use only. The FDI Calculator is provided for research and educational purposes. It is not a medical device and must not be used as the sole basis for clinical decisions. Clinical management should integrate swallowing assessment findings with functional status, diagnosis, and the patient's individual context. Pending external validation.