Target Trial Emulation: Considerations for Physical Therapy Research

Randomized clinical trials (RCTs) are considered the ideal method for assessing the effectiveness of physical therapist interventions. However, RCTs are resource-intensive and usually take several years to complete, often providing insights well after they are needed to inform practice. Due to the constantly evolving nature of physical therapy, study designs are needed that can more rapidly generate evidence that can be used to guide clinical care. Target trial emulation (TTE) provides a framework that improves researchers' abilities to draw causal inferences from observational data, by specifying protocol components of a hypothetical RCT and emulating those components with observational data elements. By leveraging data generated through routine care encounters, TTE allows researchers to examine the effectiveness of interventions as they are being used in clinical care - enhancing researchers' abilities to generate evidence when it is most needed. However, TTE has not been used extensively among physical therapy researchers, potentially due to a lack of familiarity with this concept or challenges related to the way physical therapy is delivered or the types of data generated during physical therapist encounters. In this manuscript, the authors provide an introduction to the TTE framework, using an ongoing study examining the effectiveness of remote therapeutic monitoring as a case example. The authors also discuss considerations and challenges associated with TTE studies within the context of physical therapy and recommend strategies for addressing these challenges. They also discuss how TTE studies can be enhanced through the addition of implementation-focused data collection and conclude with a discussion of limitations associated with TTE studies.