Methodological diversity can augment progress in psychological research

Wachtel identified four interrelated constraints on research: biases against theory and description, emphasis on productivity, grant funding that may unwittingly foster the previous two constraints as well as limit the focus of research, and limits of experimental methods. The present comments focus on two main issues. First, heavy and almost exclusive reliance on research in the quantitative tradition is an unnecessary constraint. The tradition is infrequently questioned not only because of the contributions we enjoy from it (e.g., evidence-based everything), but also because it is so pervasive that it is the water in which we swim. There is nothing fishy about that tradition, but other traditions (e.g., single-case and qualitative research) would greatly expand and complement the yield and generate as well as test theory in new ways. Second, progress in research is an important topic by itself and warrants analysis. It would be useful to characterize areas where progress has been extraordinary or slow with the hope of learning what might be done to accelerate progress.