Structure, Reliability, and Validity of the Bengali Version of the Pain Catastrophizing Scale in Musculoskeletal Chronic Pain Patients in India.

BACKGROUND

Elevated pain catastrophizing increases the severity of pain experience. The 13-item Pain Catastrophizing Scale (PCS) can aid in managing chronic pain. Chronic musculoskeletal pain (CMSP) is common among the native Bengali population in India seeking treatment.

PURPOSE: This study aimed to culturally adapt and psychometrically validate the original PCS under the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines, with a novel goal to examine the factor structure of pain catastrophizing in native Bengali CMSP patients in India and compare it with the theoretical pain appraisal model.

STUDY

OBJECTIVES

The primary objective of this study was to translate and cross-culturally adapt the original PCS into a Bengali version for use in India (BNGA-IND-PCS). The secondary objective was to examine the psychometric properties of BNGA-IND-PCS in patients with CMSP.

METHODS

The Bengali version of the PCS for India (BNGA-IND-PCS) was created through forward and backward translation, evaluated by a committee of clinical and language experts, and pre-tested in 30 CMSP patients. The sample size was determined from a 10:1 sample-to-item ratio. A total of 253 CMSP patients (pain duration ≥ 6 months) from convenience sampling were included in the cross-sectional observational study to perform psychometric validation, comprising factor structure determination, internal consistency, test-retest reliability, and concurrent validity (pain severity, anxiety, and depression).

RESULTS

Confirmatory factor analysis showed that the BNGA-IND-PCS two-factor model (pain reflection and helplessness) provided the best fit with a borderline acceptable root mean square error of approximation of 0.06. Internal consistency (Cronbach's α = 0.921) and test-retest reliability (intra-class correlation coefficient = 0.852, 95% CI: 0.772-0.903) of total BNGA-IND-PCS scores were good to excellent and adhered to the COSMIN criteria. Total BNGA-IND-PCS scores moderately correlated with pain severity, anxiety, and depression (r = 0.406-0.549, p < 0.01).

CONCLUSION

The PCS translation and cross-cultural adaptation into Bengali demonstrated a two-factor structure and good-to-excellent psychometric properties in a single-sample validation. Future studies with large-scale patient samples are required to test the "ecological validity" under clinical settings.