Restless leg syndrome (SNOMED-CT) V1.3

To identify restless leg syndrome, a code list was created by José Ignacio Cuitún Coronado (Senior Research Associate in Medical Statistics and Applied Health Data Science, University of Bristol) and reviewed by Elizabeth Coulthard (Professor of Cognitive Neurology, University of Bristol).

Step 1. We searched for the following key terms:

• Restless leg syndrome
• Willis-Ekbom disease
• restless

Step 2. We excluded irrelevant codes (e.g., codes indicating a prevalent diagnosis or where the diagnosis was unclear):

(A) Codes that identify a prevalent diagnosis:

• History of

(B) Codes that do not relate to the person:

• Family history

(C) Codes where the diagnosis is unclear:

• Assessment
• At risk
• Attendance
• Battery
• Tool
• Referral
• Invite / invitation

(D) Codes excluded upon review by the clinician:

• Society
• Committee
• Medication (partial exclusion)
• Substances (partial exclusion)
• Drugs (partial exclusion)
• Measure / measurement / test / scale questionnaire

No medication/drug/substance(s) were removed unless there was a clear example from the clinician.