Validity and Reliability of the Thai Version of Neuropathic Pain Symptom Inventory (NPSI - T)

Abstract

Background: The aim of this study was to evaluate validity and reliability of the Thai version of the Neuropathic Pain Symptom Inventory (NPSI - T) in Thai patients with neuropathic pain. Although the Thai version of Neuropathic Pain Symptom Inventory (NPSI - T) has been linguistically validated, the tool has to be psychometrically validated before applying to neuropathic pain patients in daily practice.

Method: Forty Thai patients with diagnosis of neuropathic pain were enrolled to rate the visual analog scale (VAS), the Thai version of Neuropathic Pain Diagnostic Questionnaire (DN4 - T) and NPSI - T questionnaires and performed retest NPSI - T in four hours later. The patients were also asked to explain the understanding of the wording in each question of NPSI - T.

Result: The total score of NPSI - T questionnaire was correlated to visual analog scale (VAS) (Spearman’s correlation coefficient = 0.599, P < 0.001) and Neuropathic Pain Diagnostic Questionnaire (DN4 - T) (Spearman’s correlation coefficient = 0.695, P < 0.001). The reliability was determined by Intraclass correlation coefficient (ICC), an excellent interobserver agreement (ICC > 0.8) was presented in 30% of the questionnaire and good agreement (ICC 0.6 - 0.8) was 70% of the questionnaire.

Conclusion: Our study showed the validity of the NPSI - T and demonstrated its reliability for assessing the neuropathic pain in Thai patients.