Simple Lower Limb Functional Tests in Patients With Chronic Obstructive Pulmonary Disease: A Systematic Review

ObjectivesTo evaluate the characteristics and available evidence on the measurement properties of the gait speed (GS) test, timed Up and Go test (TUG), sit-to-stand (STS) test, and step test; to investigate their relation with clinical outcomes in chronic obstructive pulmonary disease (COPD); and to provide recommendations for clinical practice and future research.Data SourcesStudies were systematically identified from a literature search using PubMed, PEDro, CINAHL, and Cochrane Library databases and the reference lists of the included articles.Study SelectionStudies including ≥1 of these 4 lower limb functional tests (GS test, TUG, STS test, and step test) as an outcome in patients with COPD were selected. No limits were applied for language and study design.Data ExtractionTwo researchers independently performed data extraction and, by using the COnsensus-based standards for the Selection of health status measurement INstruments, assessed the quality of those studies that described measurement properties.Data SynthesisForty-two articles met the selection criteria. GS test, STS test, and step test are valid, reproducible, and responsive tests, especially the 4-meter GS, 5-repetition STS test, and 6-minute step test (6MST). The TUG is reliable; however, studies on other measurement properties of this test are lacking. Outcomes of these tests are correlated with mortality, physical activity in daily life, exercise capacity, dyspnea, and quality of life.ConclusionsSimple and functional lower limb tests provide information about important clinical outcomes in patients with COPD. The 4-meter GS, 5-repetition STS test, and 6MST are tests with well-established psychometric properties, whereas the properties of the TUG need to be studied further.