Validity and reliability of the Persian Boston questionnaire in Iranian patients with carpal tunnel syndrome

Using Boston questionnaire (BQ) is common to evaluate the severity and functional ability in patients with carpal tunnel syndrome (CTS). This study aimed to translate and adapt the Persian version of BQ for the assessment of the severity and investigation of its validity and reliability. BQ has two parts: first part with 11 questions evaluates the severity of symptoms (BQ-SS) and the other part with 8 questions evaluates the functional status (BQ-FS) of patients. After translation and preparing the Persian version of BQ by two translators، it has been re-translated to English and matched to the original. For content and construct validity evaluation، the opinions of 15 patients with CTS and 20 specialist medical doctors were used. They were asked to complete the final Persian version of BQ. To investigate the reliability، 45 CTS patients (age ranged 20-60 years old، 86 affected wrists) in two groups; low-literate and literate، completed Persian BQ in two different sessions with at least 2 weeks interval for each affected hand. Using Cronbach''s alpha، showed excellent internal consistency for both literate (BQ-SS= 0. 88، BQ-FS= 0. 90) and low-literate (BQ-SS= 0. 90، BQ-FS= 0. 90) subjects. The intraclass correlation oefficients were also excellent in both literate (BQ-SS= 0. 834، P<0. 01 and BQ-FS= 0. 91، P<0. 001) and low-literate (BQ-SS= 0. 90، P<0. 001 and BQ-FS= 0. 89، P<0. 001) subjects Pearson’s correlation coefficient of BQ-SS and BQ-FS were 0. 84 and 0. 90 for literate and 0. 90 and 0. 89 for low-literate subjects. The results showed that the Persian version of BQ is a reliable tool in both literate and low-literate Iranian CTS patients. However، it is necessary to investigate its reliability in CTS patients over 60 years old.