Pedagogical content knowledge: A systematic review of the way in which the concept has pervaded mathematics educational research

•PCK is differently conceptualized in empirical mathematics education research.•Large-scale studies often measure PCK through a paper-and-pencil test.•Small-scale studies typically use multiple qualitative data sources.•Half of the PCK-studies investigates the development of (pre-service) teachers' PCK.

Pedagogical content knowledge (PCK) was introduced by Shulman in 1986 and refers to the knowledge teachers use to translate particular subject matter to students, taking into account possible (mis)conceptions. PCK was – and still is – very influential in research on teaching and teacher education, mainly within the natural sciences. The present study aims at a systematic review of the way PCK was conceptualized and (empirically) studied in mathematics education research. Based on a systematic search in the databases Eric, PsycInfo and Web of Science 60 articles were reviewed. We identified different conceptualizations of PCK that in turn had a differential influence on the methods used in the study of PCK.