Adaptação transcultural e validação do instrumento oral anticoagulation knowledge (OAK) test para o Português do Brasil

Abstract

The high prevalence of morbidity and mortality related to the use of drugs constitutes a public health problem. Warfarin is among the main drugs associated with accidental deaths and other adverse events, resulting in harm to the patient. Knowledge of patients on drug therapy of oral anticoagulation, therefore, plays a key role in preventing serious complications because the risk of bleeding or thromboembolism increases with incorrect use of warfarin. No valid and reliable instrument for the assessment of the patient's knowledge of anticoagulant therapy with warfarin for use in the Brazilian population. This study was conducted the cross-cultural adaptation and validation of the instrument Oral Anticoagulation Knowledge (OAK) Test. The used method was involved the initial translation, synthesis of translations, back translation, review by the committee of experts, pre-testing and validation of psychometric properties. The process of cultural adaptation showed that Brazilian and American versions are conceptually equivalent and that the obtained instrument has good psychometric properties. Cronbach's equal to 0.818 and the intraclass correlation coefficient equal to 0.967 were obtained. The convergent construct validity showed a strong positive correlation between the values of the level of knowledge by OAK Test and time within therapeutic range - TTR (rs = 0,780). The Portuguese version of Brazil entitled "Knowledge Test on Oral Anticoagulation" is reliable and valid for assessing the knowledge of Brazilian patients on anticoagulation therapy with warfarin. The results generated by the application of the adapted instrument may be incorporated into the practice of public health care to help structuring health education activities to ensure improved knowledge which may improve the effectiveness and safety of the treatment.