Precision medicine requires precise definitions and theory: Commentary on Zilcha-Mano (2020).

Zilcha-Mano (2020) suggests that making a distinction between trait-like and state-like (TLSL) processes is the key to developing personalized treatments. In the current commentary, I question the novelty of the TLSL concept and emphasize the importance of having clearly defined, psychometrically sound concepts applied to psychotherapy research for it to advance. I raise questions regarding application of TLSL to psychotherapy on conceptual and methodological grounds, with an emphasis that answers to these questions are needed to advance the TLSL distinction. (PsycInfo Database Record (c) 2022 APA, all rights reserved).