ABC | Volume 111, Nº6, December 2018

Original Article Ghisi et al Validation of the Brazilian-Portuguese CADE-Q SV Arq Bras Cardiol. 2018; 111(6):841-849 Clarity of items ranged from 7.8 to 9.6, and overall clarity of the tool was 8.6 ± 3.2, which shows the Portuguese version of CADE-Q SV was clear to patients. Psychometric validation The internal consistency of the entire sample was assessed by KR-20(0.70). Regarding factor analysis, results from the Kaiser-Meyer-Olkin index (KMO = 0.78) and Bartlett’s Sphericity tests ( X 2 = 490.481, p < 0.001) indicated that the data were suitable for factor analysis. Six factors were extracted, representing 59.0% of the total variance. All factors were reliable (Cronbach’s alpha ranged from 0.70-0.81). These factors were called: medical, risk factors, exercise, diet, psychosocial risk, and specific cases. Table 3 shows the factor loadings for each item based on loadings greater than 0.30 on only one factor. The test-retest reliability was evaluated through the ICC for each item, and the ICCs for all items meet the minimum recommended standard. In regard to construct validity, CADE-Q SV total scores were compared by participant’s level of education, family monthly income and time of diagnosis. As shown in Table 1, patients with lower educational level had significantly higher needs than those with higher education (p < 0.001), and participants with no income or less than 1 minimum salary had lower knowledge than participants that earn 4 minimum salaries per month or higher (p < 0.05). No differences were found regarding time of diagnosis. Cardiovascular patients’ knowledge about their condition Table 2 displays the means and standard deviations of each CADE-Q SV item, as well as total scores per area. Items with the highest scores (i.e., with the highest number of correct answers) were the following: “to help control your blood pressure, eat less salt and exercise regularly”, “stress increases your chance of having a heart attack as much as high blood pressure and diabetes”, and “to help lower your blood pressure, eat healthy foods more often, such as vegetables, fruits, and whole grains”. Items with the lowest knowledge (i.e., items with the lowest scores) were the following: “ ‘statin’ medications (such as atorvastatin and simvastatin) limit how much cholesterol your body absorbs from food”, “sleep apnea (pauses in breathing during sleep) can increase your chance of having another heart attack”, and “the only effective way to manage stress is to avoid people who cause unpleasant feelings”. The area with the highest knowledge was risk factors and the one with the lowest was psychosocial risk. Patients spend around 10 minutes to complete the tool. Table 1 presents the total score per participant’s characteristics. As displayed, patients that had a myocardial infarction or have arrhythmia had significantly higher knowledge than their counterparts (p < 0.05). In addition, younger participants (i.e. less than 65 years old) had significantly higher knowledge than participants who were 65 years old or older. Discussion Education is a core component of CR and cardiac care, and is necessary to promote patient’s understanding of secondary prevention strategies and adherence to these strategies. Herein, a short and reliable tool to assess cardiovascular patients’ knowledge – called CADE-Q SV - has been translated, culturally adapted, and psychometrically validated through a rigorous process. Internal consistency, test-retest reliability, criterion validity, and factor structure were all established, and demonstrate the utility of this tool. Results of this study were consistent with those presented in the original validation, 21 particularly in relation to criterion validity (correlation to educational level) and all areas being considered internally consistent ( α > 0.70). In this validation, there are 6 factors, even thoughthe tool has 5 areas. The new factor was called “specific cases” and included questions related to comorbidities and specific diagnosis that may not be relevant to all cardiovascular patients (e.g., diabetes and sleep apnea). Adult patients learn based on their personal needs and when the information is not relevant to them they may not have interest to learn about it. 28,29 Therefore, these items were combined in one factor and in future studies with the tool, researchers should flag these items and see if cardiovascular patients with or without these comorbidities will have the same knowledge. The overall mean, as well as the means of the areas, were low, reinforcing the need for educational strategies to teach cardiovascular patients, which have been reinforced in publications about strategies to treat these patients in low‑and middle-income countries. 14 Thus, the areas with higher knowledge in this study (risk factors) were different from the areas identified in the original validation (exercise and diet). 21 This result was expected since in this study we have administered the survey in ambulatory cardiovascular patients, while the original study was with CR patients. Future research is needed to further establish the psychometric properties of the Portuguese version of CADE-Q SV. First, in relation to the potential strategies to educate cardiovascular patients, it should be determined whether the scale is sensitive to change (i.e., responsiveness), such as after CR or educational programs. Second, there are other measurement properties of the scale that require assessment, such as criterion validity. Moreover, test-retest reliability was performed in 20 patients, and the literature points that the minimum number should be 50. 27 Third, the type of sample and the fact that participants were recruited from only one site also limits this study. Therefore, the Portuguese CADE-Q SV should be administered in other health programs and Brazilian states, to ensure it is appropriate and performs well in more general settings. Finally, future research is needed to assess whether the scale is sensitive to change, such as following participation in CR, or to test implementation of new education materials. Second, whether CADE-Q SV is a valuable and valid tool to identify knowledge differences in CR patients should be explored. 30 For this study patients did not receive any feedback regarding their knowledge; however, we encourage clinicians and researchers to provide this to patients. Conclusions In conclusion, the Portuguese version of CADE-Q SV proved to have strong psychometric properties, providing 845