Data analysis

Quantitative analysis

We will perform a descriptive analysis of the categorical variables (absolute and relative frequencies), and the continuous variables (median and range) ( Extended data 5 ⁴⁶).

Qualitative analysis

We will analyse and synthesise qualitative data using a thematic synthesis. We will register in an Excel sheet quotes from: 1) educational documents and resources, and 2) semi-structured interviews. We will identify themes related to the educational context applying a three-step descriptive thematic synthesis: 1) codifying extracted quotes, 2) proposing descriptive themes, and 3) identifying main themes based on conceptual similarities within and across quotes. We will describe the extent of duplication and overlapping themes within and across documents. If applicable, we will map how themes reflect the IHC Key Concepts framework through a data matrix (including documents as rows and the IHC Key Concepts as columns). ⁶ One author will codify extracted quotes and propose descriptive themes. Two authors will select the descriptive themes, identify main themes, and assess the overlap with the IHC Key Concepts guided by iterative discussion, and if necessary, by consulting a third author. The authors’ team will approve the final synthesis of findings.

Finally, using the summarised data, we will explore the nature of the phenomena (how critical thinking about health is being taught and learned in Spanish primary schools), and the possible explanations for the findings. Furthermore, we will deepen our understanding of the opportunities for and barriers to teaching and learning critical thinking in general, about health in general, and critical thinking specifically about health.