Are Interventions Supporting Physical Activity Modified by the Environment (InSPACE): Study protocol for randomized controlled trial pooling project (Preprint)

<sec> <title>BACKGROUND</title> Physical activity (PA) interventions can increase levels of PA and help participants meet the recommended levels of physical activity. The impact of physical activity interventions may be affected by an individual’s neighborhood environment, including attributes such as walkability, crime rates, or greenspace, but research to date has lacked the power and geographic spread to adequately assess the role of the environment. </sec> <sec> <title>OBJECTIVE</title> The Interventions Supporting Physical ACtivity and the Environment (InSPACE) study used the Automated Context Measurement Tool (ACMT) to gather environmental measures for participants around their home address in completed lifestyle intervention trials across the U.S., then pooled and harmonized demographic and device-based activity data to assess the effect of neighborhood attributes on interventions to increase PA. </sec> <sec> <title>METHODS</title> This paper describes the trial recruitment, data gathering, and data harmonization protocols within InSPACE. It further describes the process of combining data across intervention trials, including harmonization of demographic data and of accelerometry data across various accelerometer types, wear locations, and participant ages. </sec> <sec> <title>RESULTS</title> As of July 2025, a total of 39 physical activity intervention trials have been recruited and data from 30 of these trials have been processed and harmonized, creating a current pooled dataset of 3,561 participants with harmonized data, of whom 1,916 (54%) have valid (3 days of at least 10 hours per day) accelerometry data for both baseline and post-intervention. </sec> <sec> <title>CONCLUSIONS</title> InSPACE will contribute to understanding the role of the environment in moderating the effect of interventions to increase physical activity. The protocols and processes of InSPACE can inform future projects in pooled data harmonization and analysis. </sec>