The aim of this study was to investigate the validity and reliability of the Upper Extremity Functional Index in patients with carpal tunnel syndrome. This cross-sectional study included 101 patients diagnosed with carpal tunnel syndrome at a university hospital. Patients were administered the Upper Extremity Functional Index, Michigan Hand Outcomes Questionnaire, and Boston Carpal Tunnel Questionnaire surveys. Test-retest reliability, internal consistency, and construct validity of the Upper Extremity Fuctional Index were evaluated.

Inclusion Criteria:

• To be diagnosed with carpal tunnel syndrome, to be a volunteer, and to be between the ages of 18 and 65 years.

Exclusion Criteria:

• no history of other trauma, disease or surgery in the affected limb and difficulty communicating

This study included patients aged 18-65 years who were diagnosed with carpal tunnel syndrome after visiting the neurology outpatient clinic of a university hospital, who volunteered, who had no history of other trauma, disease, or surgery in the affected limb, and who had no communication difficulties. The patients were included before starting any conservative or surgical treatment programme.