On “Toward systems science in rehabilitation.” Jette AM. Phys Ther. 2016;96:270–271.

This editorial¹ is a welcome addition to the dialogue of clinical epistemology and establishing a knowledge-based practice. It shifts the focus from isolation to systems and from a form of hyper-empirical inquiry to one more in tune with a critical realist foundation for clinical epistemology. There is a close coherence between critical realism and systems science (approaches, thinking), with a nice summary of this coherence by John Mingers.² This topic has been of interest to me for quite some time. In my experience, the more “meta” our attempt at epistemology, the greater the need for a dialectical approach. I first suggested the use of complex systems approaches to enhance the relevance of clinical research back in 2005 in a letter to the editor in PTJ.³ Since then, I have spent time developing a clinical epistemological approach founded on critical realism that can allow for a balance between the empirical and rational processes associated with knowledge development and justification (epistemology) and the use of causal networks that provide a representation of knowledge and a structure from which to generate and evaluate reasoning patterns (dynamic inferential patterns using inductive, deductive, abductive, and Bayesian inference) to be used in practice (greatly influenced by Judea Pearl⁴).

There are 2 recent editorials that uncover some of these ideas in Cardiopulmonary Physical Therapy Journal.^5,6 There also is a blog⁷ that started in early 2015 to walk through the ideas in a public forum and gather feedback (in a modern-day dialectic). For the most part, that process has been beneficial, as discussions percolated that challenged and refined the underlying concept. Like most blogs, it is presented in reverse chronological order, so I also have linked to a page that includes a PDF compilation document of the first few months in sequential order that—although rough—elucidates many of the core ideas.⁸ In my current role (program director of a developing DPT program), I am putting these ideas to use in the development of a DPT curriculum that explicitly includes “systems” as a meta core concept in a primarily concept-based curriculum (other concepts being causation, adaptation, and movement).⁹

Another benefit that Dr Jette may get to in his editorial series on this topic is the usefulness of systems approaches to help with the delineation and development of our theory and practice of the movement system. Systems approaches need not stop at helping us develop our clinical epistemology; they also can help us develop the object of our epistemology (movement).

It should be clear by now that I read Dr Jette's editorial with great interest and hope it inspires a robust discussion within the profession. Through this robust discussion, we can be sure that the pendulum does not swing too far toward the elucidation of Plan-Do-Study-Act cycles as the primary means of clinical epistemology. At the end of the day, these cycles include a combination of particulars in an attempt to generate universal understanding with human reasoning at the center. This includes all of the limitations of that process and the inherent biases associated with unstructured human observations, including actively biasing behavior that the randomized controlled trials and other more structured observations help (at least partly) protect us against.¹⁰ Thank you, Dr Jette, for bringing such an important topic as clinical epistemology and systems science to the national forefront through the readership of PTJ.

• © 2016 American Physical Therapy Association