Elaboração e validação de conteúdo de um instrumento de avaliação da motivação para perda de peso em adolescentes com sobrepeso e obesidade

Abstract

Obesity in adolescence is currently a serious public health problem in Brazil and in the world. In this sense, the reduction and control of body weight represents an important measure to reduce the risks associated with obesity over time. However, among adolescents the main motivations for weight loss are related to improving appearance and acceptance by peers. In this context, the present study aims to elaborate and validate the content of a questionnaire for evaluation of the motivation for weight loss in adolescents with overweight and obesity. This is a crosssectional, methodological study with descriptive and explanatory objectives, which used bibliographical research and the survey as technical procedures and the quantitative data analysis approach. The preparation and validation of the questionnaire were conducted in five stages. In the first stage, it was the definition of the construct to be evaluated by the instrument, the motivation for weight loss. In the second stage, for identifying the properties of the construct, a systematic review was performed to identify the motivations for weight loss in adolescents with overweight and/or obesity. This systematic review included six studies and provided the identification of the 17 items for the initial version of the instrument. The most frequent motivations in the studies were: to have better health, to improve my selfesteem, to improve my appearance and to avoid provocations/bullying. In the third stage, to identify the theoretical domains, a systematic review was performed on questionnaires assessing the motivation for weight loss applicable to people with overweight or obesity in any age group. This systematic review included six studies and provided the identification of domains for the categorization of questionnaire items. The fourth stage consisted of the definition of the items for the initial version of the questionnaire. In this step, all the motivations identified in step 2 through of the systematic review were maintained. In stage five, the content validity of the instrument was analyzed by a panel of 12 specialists, composed of nutritionists, endocrinologists, psychologists and physical educators. Based on the scores attributed to the items by the judges, the content validity index (CVI) was calculated. After the evaluation of the 12 specialists, five motivations were excluded because they presented CVI <0.80 for practical relevance. Five items (out of 12 retained in the instrument) were reviewed and re-submitted for expert evaluation to improve language clarity for the target audience of the instrument, as well as to standardize the presentation of the items. The twelve items kept in the instrument were categorized by the specialists in four domains (health, social, appearance and personal satisfaction). To our knowledge, the instrument developed is the first to assess the motivation for weight loss in adolescents with overweight and obesity. The systematic review for the selection of the items contributed to the theoretical basis of the instrument, while the evaluation of the practical relevance of the items by the judges provided the identification of which motivations were more representative for the target audience of the instrument.