Questionário de conhecimento em Doença Arterial Periférica (DAP-Q): desenvolvimento e avaliação psicométrica

Abstract

INTRODUCTION: Health education is an integral part of the treatment of individuals with Peripheral Arterial Disease (PAD). Identifying the knowledge needs of patients with PAD can guide healthcare professionals in developing a personalized education program and, thus, improving disease-related knowledge, leading to behavior change and, consequently, better clinical and functional outcomes. Assessing the knowledge needs of individuals with PAD is challenging. Furthermore, there is no comprehensive questionnaire to assess this knowledge with measurement properties. Considering the importance of the educational process within rehabilitation programs, it is important to develop and investigate the measurement properties of a questionnaire so that it can be used in the Brazilian population, thus complementing the PAD care pathway. OBJECTIVE: To develop and evaluate the measurement properties of a questionnaire to assess PAD knowledge in individuals with the disease. METHOD: This is a methodological study to develop and evaluate the measurement properties of the "PAD Knowledge Questionnaire – PAD-Q," approved by the Research Ethics Committee of the Federal University of Minas Gerais. The process of developing and evaluating the questionnaire's measurement properties included three procedures: theoretical, empirical, and analytical. The theoretical procedure consisted of a theoretical foundation for the DAP knowledge construct and was conducted through a scoping review (Article 1), focus groups and online surveys (Article 2), a Delphi panel, and a committee of experts. The empirical procedure involved administering the pilot instrument, based on the information gathered in the previous stage, to a sample of 30 individuals to assess the comprehension and clarity of the questionnaire questions. The analytical procedure consisted of evaluating the questionnaire's psychometric properties, which followed the recommendations of the COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) initiative (Article 3). The reliability and validity domains were investigated through the following properties: test-retest reliability, based on the Intraclass Correlation Coefficient (ICC); internal consistency, using Cronbach's alpha coefficient; content validity; and construct validity, using exploratory factor analysis to determine the knowledge areas of the PAD-Q, based on the hypothesis that PAD-Q scores would be higher in questionnaires answered by individuals with higher levels of education and family income, higher Ankle-Brachial Index (ABI), and the presence of ceiling and floor effects. For all statistical tests, a significance level of 5% alpha was considered. RESULTS: In the theoretical procedure, relevant items were identified for assessing the knowledge of patients with PAD. In the empirical procedure, only one question required adjustment, indicating good overall comprehension and clarity of the developed questionnaire. The reliability tested by the ICC was 0.72 (95% CI: 0.71–0.73), and internal consistency was 0.79 (95% CI: 0.74–0.84). Content validity was assessed through a literature review and the opinions of professionals, students, and individuals with PAD. The questionnaire was divided into five factors: "General Characteristics," "Control and Consequences," "Modifiable Risk Factors and Treatments," "Trophic Changes," and "Non-modifiable Risk Factors and Symptoms." No correlations were found between the total PAD-Q score and education level, income, or ABI, possibly due to the multidimensional and interdependent nature of the questionnaire. The questionnaire did not present ceiling or floor effects. CONCLUSION: The PAD-Q demonstrated adequate measurement properties for assessing the knowledge of individuals with PAD. Therefore, the questionnaire can aid in treatment, guide health professionals, and provide information to support self-management of the health of individuals with PAD.