Reliability and Validity of the Persian Version of the Body Image Disturbance Questionnaire-Scoliosis in Patients with Adolescent Idiopathic Scoliosis Who Did Not Have Surgical Indication

Background: Adolescent Idiopathic Scoliosis (AIS) is the most common spinal deformity disorder associated with bad posture and reduced quality of life. The Body Image Disturbance Questionnaire-Scoliosis (BIDQ-S) is a self-report instrument that assesses the concerns of scoliotic patients. This study aimed to translate and evaluate the reproducibility and internal consistency of the BIDQ-S in the Persian-speaking population worldwide suffering from AIS.

Methods: The BIDQ-S was translated into Persian by two native-speaking Iranian translators and back-translated into English by two native-English translators. The resulting back-translated English BIDQ-S was then sent to the authors of the English BIDQ-S questionnaire for validation. After translation, it was provided for 41 AIS patients from those who referred to the outpatient clinics of Shafa Yahyaian Hospital from January 2020 to January 2021. Patients were asked to complete the Persian BIDQ-S and Persian Scoliosis Research Society-22 (SRS-22) inventories. Internal consistency and reproducibility were assessed using Cronbach's alpha and interclass correlation coefficients (ICC), respectively. The validity of the questionnaire was evaluated by comparing the scores obtained on the Persian BIDQ-S (P-BIDQ-S) inventory with those obtained on the SRS-22 subscales.

Results: The consistency and reliability of the P- BIDQ-S inventory were confirmed by Cronbach's alpha of 0.856 and interclass correlation coefficients of 0.882. The P-BIDQ-S scores directly correlated with the level of education of patients (r=0.21, P=0.041). The correlation coefficient between the P-BIDQ-S inventory and the SRS-22 questionnaire was -0.56 (P=0.001). A significant correlation was also observed between the P-BIDQ-S items and all of the SRS-22 subscales (P<0.05).

Conclusion: The P-BIDQ-S inventory maintains adequate reliability, internal consistency, and reproducibility for the evaluation of Persian-speaking AIS patients.