Rasch Modelling to Assess Psychometric Validation of the Knowledge about Tuberculosis Questionnaire (KATUB-Q) for the General Population in Indonesia

Objective: This study aims to validate and evaluate the psychometric properties of the knowledge about tuberculosis questionnaire (KATUB-Q) for the general population in Indonesia. Methods: The KATUB-Q consists of three domains: general knowledge, transmission, and treatment, with 20 dichotomous items. Rasch analysis through WINSTEPS was used. Results: A total of 504 respondents from 34 provinces in Indonesia completed the survey. Based on the model fit statistics, 3 misfit items were deleted and 17 items were used. Item and person reliability, as well as Cronbach’s Alpha values were 0.99, 0.63, and 0.73, respectively, which means they achieved the minimum acceptable limit of 0.6. Based on the results, Indonesia’s Person ability analysis indicated a high level of knowledge. KATUB-Q has no significant bias item based on sex found in the differential item functioning analysis. Conclusion: KATUB-Q has 17 items with a valid and reliable instrument; hence, it can be used to measure the knowledge about TB in the general population. Practice implications: The unidimensional structure of the core items of the KATUB-Q provides empirical evidence for using the sum score of the items in practice to evaluate the effectiveness of TB education in the general population.