Integrated Structural Analysis of Trunk Function Assessment After Stroke-New Evaluation Model Based on Multiscale...

To investigate the components of trunk function using multiple existing assessments and construct a new evaluation model.

A prospective observational cohort study with a 1-week follow-up.

A single-center tertiary care hospital.

In total, 200 patients with early-onset stroke (mean age, 75.9±12y; 57% male) were consecutively recruited. Key inclusion criteria were a diagnosis of acute cerebral infarction or hemorrhage and the ability to mobilize within 48 hours of onset.

Not applicable.

The prespecified primary outcome measure was trunk function, assessed 1.2±2.5 days poststroke using the Verheyden and Fujiwara Trunk Impairment Scales, Functional Assessment for Control of Trunk, and Trunk Control Test. Exploratory factor analysis was used to classify functional factors, followed by Rasch analysis to confirm unidimensionality and item difficulty within each factor. Assessors were not blinded to participants' clinical information.

Exploratory factor analysis identified 4 functional factors: static sitting, basic movements, and dynamic sitting tasks (more challenging and less challenging). Rasch analysis confirmed unidimensionality for all factors after excluding 4 items from the less challenging dynamic sitting factor. The resulting factors and item difficulties revealed a hierarchical pattern, suggesting that trunk function recovery progresses from static controlled movements to complex dynamic movements.

To our knowledge, this is the first study to clarify the factor structure and hierarchical organization of trunk function after stroke, providing a framework to reorganize evaluation tools and improve personalized physical therapy. Further research is needed to develop a short-form version to enhance clinical utility.