Cross-Cultural Adaptation and Psychometric Properties of The Thai Versions of The Patient-Reported Outcomes Measurement Information System Short Form – Anxiety 8a and the Pain Anxiety Symptoms Scale-20 in Individuals with Chronic Low Back Pain

Abstract

Objective: To translate and cross-culturally adapt the Patient-Reported Outcomes Measurement Information System Short Form v1.0–Anxiety 8a and the Pain Anxiety Symptoms Scale-20 into Thai versions (T-PROMIS-Anx8a and T-PASS-20, respectively) and evaluate their psychometric properties in individuals with chronic low back pain (CLBP).Material and Methods: The translations and cultural adaptations were performed using the Functional Assessment of Chronic Illness Therapy (FACIT) guidelines. Thai individuals with CLBP completed the T-PROMIS-Anx8a and T-PASS-20. Psychometric evaluation including: internal consistency, test-retest reliability, and dimensionality. Construct validity was evaluated by computing correlations among the scores on the T-PROMIS-Anx8a, T-PASS-20, Thai version of the Hospital Anxiety and Depression Scale–Anxiety (T-HADS-A), and Thai version of the Fear Avoidance Beliefs Questionnaire (T-FABQ).Results: A total of 269 individuals with CLBP were included in the analyses. The T-PROMIS-Anx8a showed unidimensionality and the T-PASS-20 evidenced a 4-factor structure. Both measures demonstrated good to excellent internal consistency (Cronbach’s alphas ranged from 0.85 to 0.95), good test-retest reliability (ICC(2,1) ranged from 0.79 to 0.88), and neither ceiling nor floor effects were observed for any of the scales. Both measures evidenced acceptable convergent and discriminant validity, based on their associations with the T-HADS-A and T-FABQ.Conclusion: The T-PROMIS-Anx8a and T-PASS-20 were culturally adapted and evidenced acceptable psychometric properties for assessing anxiety in Thai individuals with CLBP.