Psychometric Properties of the Turkish Version of Spondyloarthritis Knowledge Questionnaire: A Methodological Study

Abstract

Background: Information and education are recommended for patients with inflammatory arthritis including spondyloarthritis (SpA). However, there is no Turkish instrument available to measure the knowledge level of patients with SpA. The study aimed to translate the Spondyloarthritis Knowledge Questionnaire (SPAKE) into Turkish and investigate its validity and reliability. Methods: This methodological study was conducted between February 2023 and August 2023 in patients with SpA. Data were collected using the “Patient Characteristics Form” and the “Turkish version of SPAKE (SPAKE-T).” Language, content, item analysis, known-group technique, test–retest, and internal consistency were used to evaluate validity and reliability. Results: A total of 226 SpA patients participated in the study. The validity and reliability analysis of SPAKE-T showed the following results: (a) content validity index at item level between 0.86 and 1.00, (b) significant correlation between the total score of the questionnaire and its sub domains between 0.18 and 0.81 (P < .05), (c) item difficulty between 0.11 and 0.91, (d) item discrimination index between 0.26 and 0.81, (e) within the known group validity, significantly lower knowledge scores in patient groups with low education level, disease duration less than 10 years, and patients who did not receive education about their disease (P < .05), (f ) Cronbach alpha value was 0.80, and (g) test–retest reliability was 0.81. Conclusion: This study indicates that the SPAKE-T, which has satisfactory psychometric properties, can be easily used to assess the overall knowledge level of patients with SpA about disease self-management.