Methods
This study was a population-based cross-sectional health survey utilising a two-stage random cluster sampling design. The sample consisted of high school students aged between 12–16 years with the total student population attending high schools in a large city as the sample frame. Health literacy was measured by the Chinese version of the short form of the Test of Functional Health Literacy translated for and validated among Taiwanese adolescents. Overweight and obesity were assessed in accordance to the recommendation of the World Health Organization (WHO) Global Database of Body Mass Index classification methods. Data were analysed using logistic regression modelling techniques with adjustment to the cluster sampling effect.