Health behaviours as predictors of the Mediterranean Diet adherence: a decision tree approach
Abstract Objective: This study aimed to identify health behaviours that determine adolescent’s adherence to the Mediterranean Diet through a decision tree statistical approach Design: Cross-sectional study, with data collected through a self-fulfilment questionnaire with five sections: 1) eating habits; 2) adherence to the Mediterranean Diet (KIDMED Index); 3) physical activity; 4) health habits; 5) sociodemographic characteristics. Anthropometric and blood pressure data were collected by a trained research team. The Automatic Chi-square Interaction Detection (CHAID) method was used to identify health behaviours that contribute to a better adherence to the Mediterranean Diet. Setting: Eight public secondary schools, in Algarve, Portugal. Participants: Adolescents with ages between 15 and 19 years old (n 325). Results: According to the KIDMED Index, we found a low adherence to MD in 9.0% of the participants, an intermediate adherence in 45.5% and a high adherence in 45.5%. Participants that regularly have breakfast, eat vegetable soup, have a second piece of fruit per day, eat fresh or cooked vegetables one or more times a day, eat oleaginous fruits at least 2 to 3 times a week, and practice sports and leisure physical activities outside school show higher adherence to the MD (P <0.001). Conclusions: The daily intake of two pieces of fruit and vegetables proved to be a determinant health behaviour for high adherence to MD. Strategies to promote the intake of these foods among adolescents must be developed and implemented.