Our research in statistical cognition uses both qualitative and quantitative methods. A mixed method approach makes our research more comprehensive, and provides us with new directions, unexpected insights, and alternative explanations for previously established concepts. In this paper, we review four statistical cognition studies that used mixed methods and explain the contributions of both the quantitative and qualitative components. The four studies investigated concern statistical reporting practices in medical journals, an intervention aimed at improving psychologists interpretations of statistical tests, the extent to which interpretations improve when results are presented with confidence intervals (CIs) rather than p-values, and graduate students' misconceptions about CIs. Finally, we discuss the concept of scientific rigour and outline guidelines for maintaining rigour that should apply equally to qualitative and quantitative research. (Contains 1 table and 2 figures.)