Developing Indicators to Measure Critical Health Literacy in the Context of Norwegian Lower Secondary Schools

A critical health literacy (CHL) approach is recommended for promoting health in the school context. This construct is complex and includes three interconnected domains: (A) appraisal of critical information, (B) awareness of the social determinants of health (SDH), and (C) collective action to promote health and well-being. In recent literature reviews, no measurement instrument that covers all three domains of CHL in the school-context was found. Our aim was to develop self-reported measurement scales for each domain of CHL. The development process reported in this study was conducted in two stages. In the first stage, an initial item pool was generated based on literature reviews and focus group interviews (N = 15) with adolescents (steps 1-2). In the next steps, items were adjusted and removed based on the feedback from an expert panel and from representatives from the target group (steps 3-5). In stage two, we aimed to reduce the number of items and develop scales for each domain. We then piloted the current draft, which consists of 28 items (N = 114). A sub-sample (N = 10) of the participants were interviewed after they completed the survey to examine the instrument's face validity. Cronbach's α was used to assess the internal reliability of the scales; the reliability was promising for scales A (α = 0.83) and C (α = 0.85) but was below the recommended value for scale B (α = 0.61). The model fit indices were promising (TLI_scaleA = 0.97, RSMEA_scaleA = 0.055, TLI_scaleB = 1.05, RMSEA_scaleB = 0.00, TLI_scaleC = 0.95, RMSEA_scaleC = 0.074). The piloted version of scales A and C were positively correlated with subjective health literacy, health-related quality of life, and subjective health; however, we found no such correlations for scale B. The post-survey group interviews led to some adjustments in scales A and B. The revised version of CHLA-Q must be tested using a larger sample; this will enable more robust statistical testing of the properties of the items and the scale.