Cultural translation and Tunisian validation of the Drug Attitude Inventory (DAI-30) in outpatients with schizophrenia

Background: Non-adherence to treatment in patients with schizophrenia is associated with increased hospitalization, higher health care costs, and poorer long-term outcomes in terms of relapse rates. It is established that a negative drug attitude was a risk factor for non-adherence in long-term schizophrenia. The scale "Drug Attitude Inventory" is one of the scales designed to assess this concept. It has been translated and validated in different languages. However, its psychometric properties have not yet been studied in our sociocultural context. Objectives: The aims of this study were to translate into Tunisian Arabic dialect the scale "Drug Attitude Inventory" with 30 dichotomous items (DAI-30) and validate it in Tunisian sociocultural context in patients with schizophrenia. Materials and methods: This study was performed in 234 outpatients with schizophrenia, recruited through a random drawing. These patients are in remission and meet remission criteria proposed by "The Remission in schizophrenia Working Group". We recruited 30 patients for pretest and 204 patients for linguistic validation. Forward and backward translation of the DAI-30 was performed according to the protocol of the "MAPI Research Institute". This final version was submitted to 24 experts and followed by a pretest. Construct validity has been established by performing a principal component analysis factor on a sample of 204 patients. Internal consistency was assessed by Cronbach alpha coefficient and inter-rater reliability was assessed by the use of Intra-Class Correlation coefficient (ICC). For the test retest reliability evaluation, the "r" Pearson's coefficient was used between the DAI scores obtained in the initial evaluation and those obtained at 15 days. Results: Regarding construct validity, factor analysis revealed seven factors that were responsible for 59.9% of the variance. The study of internal consistency between the 30 items was rated good (alpha = 0.88). The test retest reliability was satisfactory (r = 0.99, p < 10(-3)), as well as inter-rater reliability (ICC = 0.99). Conclusion: In the Tunisian cultural context, the DAI-30 presented seven factors with good consistency and an inter-rater reliability. (C) 2014 Elsevier Inc. All rights reserved.