Reliability and validity of Turkish versions of Sciatica Bothersomeness and Sciatica Frequency Index.

Background: The Sciatica Frequency Index (SFI) and Sciatica Bothersomeness Index (SBI) are two separate indices scored for both the bothersomeness and frequency of radiating symptoms. There is no Turkish scale used specifically for sciatica.

Objective: We aimed to translate SBI and SBI in Turkish and investigate the reliability and validity of these indices.

Methods: A total of 80 patients with lumbar disc herniation (LDH) were prospectively included. Construct validity was assessed by comparing the SBI and SFI with subscales of Short Form 36 (SF-36), back and leg Numeric Rating Scale (NRS) and Roland Morris Disability Questionnaire (RMDQ). Reliability was assessed by internal consistency (Cronbach's alpha) and test-retest reliability.

Results: A weak correlation was found between SBI/SFI, back NRS and SF-36 subgroups while a moderate correlation was found between SBI/SFI, RMDQ and leg NRS. The SBI and SFI had high internal consistency measured by Cronbach's alpha (0.76 and 0.73). Test-retest reliability of the SBI and SFI were 0.95 (95% CI: 0.92-0.97) and 0.95 (95% CI: 0.92-0.97) respectively, indicating excellent reliability.

Conclusion: The Turkish versions of the SFI/SBI are a valid and reliable tool supporting their usability in patients with LDH-induced sciatica.