Study of the Psychometric Properties of the Diabetes Empowerment Scale Short Form (DES-SF)

Abstract

Introduction: The control of diabetes mellitus type 2 implies that people are actively engaged in self-care behaviours and self-efficacy is one of the variables involved in this process. Based on the Model of Behavioural Change, the Diabetes Empowerment Scale assesses the psychosocial self-efficacy of people with this disease. The aim of this study is to analyse the psychometric properties of the Portuguese version of the Diabetes Empowerment Scale (DES-SF), namely its reliability and validity. Method: A methodological nature study was conducted, with a convenience sample comprising 123 participants with diabetes mellitus type 2. In a primary health care context, the participants were asked to fill the DES-SF, the Diabetes Self-care Scale, and a sociodemographic and clinical questionnaire. Four weeks later and in order to evaluate stability over time, the self-efficacy scale was administered to a sub-sample comprised of 23 of these participants. Results: The study showed good internal consistency (Cronbach’s alpha coefficient of 0.83) and stability over time (r = 0.532, p = 0.009) of the DES-SF. The adjustment indices of the confirmatory factor analysis suggested the unidimensional nature of the scale. A positive association was found between self-efficacy and schooling (r = 0.209, p = 0.020), and self-care behaviours, in particular dietary (r = 0.221, p = 0.023) and physical exercise (r = 0.296, p = 0.002). Conclusion: Reliability and validity of the DES-SF was confirmed, which demonstrates its usefulness in the context of clinical practice or in research studies involving the Portuguese population.