Developing and Validating a Novel Tool to Enhance Functional Status Assessment: The Tennessee Functional Status Questionnaire (TFSQ)

Abstract

Purpose: Functional status is a major contributor to overall health and reflects both daily activity level (performance) and maximum attainable activity level (capacity). Existing assessment tools evaluate only 1 domain of function and do not provide insight into contributors to functional decline. We addressed these deficiencies by developing the Tennessee Functional Status Questionnaire (TFSQ), which reports activity levels in metabolic equivalents (METs) and evaluates 5 key areas: performance, capacity, activity, pain, and acute care. We validated the activity levels reported by the TFSQ against the Duke Activity Status Index (DASI). Methods: In this prospective, observational study, 120 patients completed both the TFSQ and the DASI. TFSQ-reported functional performance and capacity was correlated with DASI-calculated METs. Results: Pearson correlation between TFSQ-reported capacity and DASI-calculated METs was r = 0.69, P < .001. TFSQ capacity was significantly lower in patients who reported recently decreased activity, pain affecting function, or recent acute care exposure. Conclusions: The TFSQ is a brief and efficient assessment of patient function, standardized to METs and validated against the DASI. Our study suggests that many patients may have the functional reserve to increase daily physical activity and that factors such as changes in activity, pain, and recent acute care interaction may lower functional capacity.