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Do I have the restless legs syndrome (RLS)?

Is there a test for restless legs syndrome?

There is no blood test or imaging for the RLS.  A doctor must rely upon the symptoms you report to make a diagnosis.

There is no blood test, or any other physical test for that matter, to diagnose RLS.  A doctor will rely on clinical factors to make a diagnosis.  Typically a doctor will order a blood test for ferritin (Iron) levels and to check kidney function, blood sugar (to rule out diabetic neuropathy) and thyroid function.  The doctor will ask about medication(s) being taken.  For more information, see the description of RLS diagnosis from the Sleep Health Foundation.   Your primary care doctor (GP) usually can diagnose and treat RLS.  However, they may suggest that you see a sleep specialist or neurologist.

How is restless legs syndrome diagnosed?

Diagnostic criteria

There are 5 criteria to be met to diagnose RLS (see box 1).​​​​​

Box 1:  Criteria for diagnosing RLS

  1. A discomfort in the legs that results in an overwhelming urge to move the legs.

  2. Symptoms worsen when resting such as sitting or lying down.

  3. Symptoms improve with movement such as walking or stretching.

  4. Symptoms are worse in the evening or night.

  5. The symptoms cannot be solely attributed to another medical condition for example leg cramps, positional discomfort or arthritis.

For more information, see the "How do I know if I have RLS" section from the Restless Legs Syndrome Foundation.

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RLS diagnosis can be broadly separated into 2 categories of severity being intermittent and chronic persistent RLS.  

  1. Intermittent RLS:  Symptoms occurring on average less than twice a week for the past year, with at least five lifetime events.

  2. Chronic–persistent RLS:  Symptoms occurring on average at least twice weekly for the past year.

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RLS is also classified based on causal factors as:

  1. Primary RLS:  The RLS is the main condition being genetic or idiopathic (no known cause).

  2. Secondary RLS;  The RLS occurs as a result of another disorder (e.g. peripheral neuropathy).

RLS classification

In some instances a doctor may ask for an overnight sleep test (polysomnography) to see if there are other sleep disorders (e.g. Sleep apnoea) that may be contributing to daytime symptoms.  

The IRLS symptom rating scale

The International Restless Legs Syndrome Study Group (IRLSSG) Rating Scale (often referred to as the IRLS) is a validated, 10-item questionnaire used to assess the severity and impact of RLS symptoms over the past week.  This scale is designed to measure the severity of the RLS in patients who have already been diagnosed based on the 5 standard criteria above.  The rating scale is not a diagnostic tool, it is a symptomatic tool, designed to assess disease severity and guide therapeutic outcomes.  The patient rates each of the 10 questions on a scale of 0 to 4 being (4) Very severe (3) Severe (2) Moderate (1) Mild (0) None.

After answering all 10 questions, the scores are totaled to produce a score ranging from 0 to 40.  Very severe=31-40 points; Severe=21-30 points; Moderate=11-20; points Mild=1-10 points; None=0 points.  The IRLS 10 question rating scale can be downloaded in PDF format here.  The IRLS questionnaire is available free for clinicians at ePROVIDE™ - Online Support for Clinical Outcome Assessments.

IRLS rating scale

Measuring sleepiness: The Epworth Sleepiness Scale (ESS)

Epworth sleepiness scale

Restless Legs Syndrome (RLS) often leads to sleep onset insomnia and/or sleep fragmentation.  These disruptions in sleep quality and quantity produce daytime symptoms, one of which is excessive daytime sleepiness.  Estimates are that 20–25% of untreated patients with idiopathic RLS are at an increased risk for daytime sleepiness.  The Epworth Sleepiness Scale (ESS) is used by some physicians, as a self-administered questionnaire in the assessment of RLS patients,  Its primarily to evaluate the presence and severity of excessive daytime sleepiness.   Like the IRLSD scale above the ESS is not a diagnostic tool but rather a symptomatic measure.  The ESS is an 8 item questionnaire with each question being scored on a 0 to 3 scale of chance of dozing.  The sum of responses (0 to 24) is taken.  Sleepiness scores are listed in Box 2.  Being above 10 is generally considered indicative of excessive daytime sleepiness.    

Box 2:  Epworth Sleepiness Scale (ESS) result interpretation

0 - 5 Lower to normal daytime sleepiness

6 - 10 Higher normal daytime sleepiness

11-12 Mild excessive daytime sleepiness

13 - 15 Moderate excessive daytime sleepiness

16 - 24 Severe excessive daytime sleepiness

If an RLS patient scores above 10, it may alert the physician to look for co-existing sleep disorders, such as sleep apnoea or Periodic Limb Movement Disorder (PLMD), which could be compounding the patient's sleep quality issues.  The ESS helps doctors quantify whether a patients sleep issues are causing significant daytime impairment.  The ESS is used to track changes in a patient's condition in response to therapeutic interventions. A copy of the ESS can be downloaded as a PDF here.  For more information see the Epworth Sleepiness scale - About the ESS website.

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For more diagnostic information see the "Diagnosis" section from the Mayo Clinic or "How is the restless syndrome diagnosed" page from the National Heart, Lung and Blood foundation.

Last reviewed: 20/08/2026

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