Invited Commentary

Dijkers and the team of scholars aiming to define, classify, and measure specific treatments used within treatment sessions in rehabilitation are to be congratulated for proposing a conceptual framework for a rehabilitation treatment taxonomy (RTT) to describe interventions and evaluate their impact on rehabilitation outcomes.¹ Rehabilitation outcomes are influenced by 2 major factors: (1) patient characteristics and (2) treatment processes. The latter can be divided into: (1) factors related to clinical settings including characteristics of caregivers and health care systems and (2) specific treatment activities or interventions. As the authors state, intense efforts have been invested previously to create tools that can accurately measure different dimensions of a patient's quality of life (ie, outcomes measures).^2–12 Improvements also have been made in the ability to measure a large number of patient characteristics associated with those outcomes.^13–17 Some studies have helped understand how treatment-related factors are associated with outcomes (eg, institutional characteristics such as waiting periods or referral source,^14,18,19 clinicians' expertise and educational background,^{20–22 …}