UHDRS Calculator

Session Setup

Record patient and visit details, genetic and onset context, and the Independence Scale. The motor exam is scored 0 (normal) to 4 (severe); the functional scales (TFC, FAS, Independence) run the other way, with higher meaning better function. All data stays in this browser.

Clinical-use notice. This calculator is an unofficial scoring aid. The item descriptions shown are paraphrased summaries of the severity criteria, not the verbatim instrument. The UHDRS is © Huntington Study Group; official administration requires the licensed instrument and appropriate rater training. This tool does not replace clinical judgment and stores no data outside this browser.

Patient & Visit

Patient ID / initials

Visit date

Examiner

Visit type

Notes

Genetic & Onset Context

CAG repeat length (larger allele)

Age at visit (years) CAG and age give the CAG-Age-Product (CAP) in the summary.

Estimated age at motor onset

Predominant onset

Independence Scale

Independence level (%) Higher = more independent. Descriptions are paraphrased functional summaries.

Select a level to see its description.

Motor Assessment — Total Motor Score

Clinician-administered motor exam. Each item is rated 0 (normal) to 4 (most severe); the 31 scored items sum to the Total Motor Score (0–124). Diagnostic confidence is recorded but not added to the TMS.

▲ Clinician-rated

Total Functional Capacity

Five items rated by capacity, where higher is better. The total (0–13) maps to the classic Shoulson & Fahn HD stage, shown in the summary.

Higher = better function

Functional Assessment Scale

Twenty-five yes/no items about everyday capabilities. Each "Yes" scores 1; the total runs 0–25, with higher indicating greater independence.

Yes = 1 · higher = better function

Score Summary

UHDRS components are reported separately rather than combined into a single total. Sub-scores reflect only answered items; partially complete sections are flagged below.

Total Motor Score

— / 124

Overall completion

—

Motor · TMS

Total Motor Score · higher = worse

—/ 124

TFC

Total Functional Capacity · higher = better

—/ 13

FAS

Functional Assessment · higher = better

—/ 25

Diagnostic Confidence

Clinician's confidence motor signs are HD

—/ 4

Not rated

HD stage (from TFC)

—

Complete all 5 TFC items to derive the stage.

CAP score ⓘ

—

Enter CAG and age in Setup.

Independence Scale

—

Recorded in Setup.