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IRLS Score Interpreter

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Total and interpret the International Restless Legs Syndrome Study Group Rating Scale (IRLS) — the standard measure of RLS symptom severity. Enter the score (0–4) for each of the 10 items you recorded, and this tool returns the 0–40 total and severity band.

📄 About the instrument: the IRLS questionnaire is copyright of the MAPI Research Trust on behalf of the International RLS Study Group (IRLSSG). This page is a scoring and interpretation aid only — it does not reproduce the questionnaire wording or response options. Administer the official, licensed scale, then enter the item scores here. Obtain the validated instrument and permissions from MAPI Research Trust (eProvide).
Score each item 0–4: 0 = none · 1 = mild · 2 = moderate · 3 = severe · 4 = very severe.
0 / 40
None scored
0 of 10 items scored

Severity bands

Total scoreSeverity
0None
1–10Mild
11–20Moderate
21–30Severe
31–40Very severe
The IRLS rates severity, not diagnosis — it doesn't diagnose RLS and isn't a substitute for clinical judgement. It's most useful for a baseline and for tracking change over time. The short guide below covers the rest.

Clinical guide

Restless legs syndrome (RLS, also called Willis–Ekbom disease) is a clinical diagnosis — there is no confirmatory blood test or scan. The International RLS Study Group consensus criteria require all five of these features:

  • An urge to move the legs, usually with an uncomfortable sensation;
  • Symptoms that begin or worsen during rest or inactivity;
  • Partial or full relief with movement (such as walking or stretching), at least while moving;
  • Symptoms worse in the evening or at night;
  • The features are not solely explained by another condition (e.g. leg cramps, positional discomfort, habitual foot-tapping).

The IRLS is used after diagnosis to rate how severe the symptoms are.

The IRLS is a clinician-administered, 10-item scale (each item 0–4, total 0–40) covering symptom intensity, frequency, sleep disturbance, daytime impact and mood. It is the standard severity outcome in RLS treatment trials. In practice it's most useful as a baseline you can repeat — to follow severity over time and gauge response to treatment. A total of around 15 or more is commonly used in studies to define moderate-to-severe RLS.

Brain iron deficiency is central to RLS, so iron studies belong in the workup even when someone isn't anaemic. Take a morning, fasting serum ferritin and transferrin saturation (TSAT).

RLS uses a higher ferritin target than ordinary iron deficiency. Consensus guidelines (IRLSSG / AASM) suggest considering iron treatment when ferritin is ≤75 µg/L or TSAT <20%, and reserving IV iron for ferritin between 75 and 100. Remember ferritin is an acute-phase reactant and can read falsely high with inflammation. Treatment choices rest with the clinician and current guidelines.

Augmentation is the main long-term complication of dopaminergic treatment for RLS: symptoms paradoxically worsen — starting earlier in the day, becoming more intense, or spreading to other body parts. It's a leading cause of treatment failure, and low ferritin is associated with it (correcting iron can lower the risk). Repeating the IRLS over time helps you pick up worsening severity that may signal augmentation rather than simple disease progression.

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