Qualitative thematic analysis is a commonly used and widely applicable form of qualitative analysis, though it can be challenging to implement. Due to its use across research questions, qualitative traditions, and fields, thematic analysis is also prevalent in mixed methods studies. Despite its widespread use, the term "thematic analysis" is often confused and not always well described in empirical studies. In addition, there is limited guidance on how to use thematic analysis within the context of mixed methods research to ensure rigorous study design and mixed methods integration. Therefore, the purpose of this paper is to describe the definitions, use, and variations of thematic analysis and explore how integration and mixed methods validity may be impacted in mixed methods studies.