Anticoagulation Knowledge Tool (AKT): further evidence of validity in the Italian population

Introduction: Oral Anticoagulation therapy (OAC) is highly effective in the management of thromboembolic disorders. An adequate level of knowledge is important for self-management and optimizing clinical outcomes. The Anticoagulation Knowledge Tool (AKT) was developed to assess OAC knowledge and caters for both patients prescribed direct oral anticoagulants or vitamin K antagonist (VKA). However, evidence regarding its psychometric proprieties, validity and reliability are unavailable in non-English speaking settings. For this reason, the aim of this study is to provide further evidence of validity for AKT and also developing an Italian AKT version (I-AKT) supported by evidence of validity and reliability.

Methods: A multiphase study was conducted which included the following: cultural and linguistic validity; i.e. content validity; construct validity; reliability assessment. The Construct validity was performed using the contrasted group approach using three groups comprised of health care providers, patients and the general public. Furthermore, Exploratory Structural Equation Modelling (ESEM) was performed to confirm the mono-dimensional structure of the items in the AKT.

Results: In construct validity phase 334 participants were enrolled. One-way ANOVA and post hoc analysis test demonstrated significant differences between the means knowledge scores of the three groups: 30.42 ± 3.04 vs 23.45 ± 4.57 vs14.32 ± 6.07 (Statistic F = 266.83; p < 0.001). ESEM analysis demonstrates the I-AKT mono-dimensionally structure with an explained variance of 56.42%. The scale also showed both good internal consistency reliability (Cronbach’s α = 0.896) and test-retest reliability (r = 0.855).

Conclusion: This study developed and validated I-AKT with supporting evidence for validity and reliability. The study also confirms the mono-dimensional of the items in the AKT. This suggest that the instrument can be useful in non-English setting for knowledge assessment and in potentially developing patient education materials.