Clinical Research Directory

Validity and Reliability of the L Test in Geriatric Individuals

Age-related declines in mobility, gait speed, balance, and functional independence are major determinants of morbidity and fall risk among older adults. Widely used functional mobility assessments-such as the Timed Up and Go Test (TUG) and the 10-Meter Walk Test (10MWT)-provide valuable information but do not fully capture the multidimensional motor tasks required in daily life, such as turning, directional changes, sit-to-stand transitions, and combined mobility tasks. The L Test, originally developed as an expanded form of TUG, includes turning, curved-path walking and a longer walking distance, and may therefore offer a more comprehensive assessment of functional mobility. Although previous studies have demonstrated high test-retest reliability and significant correlations with TUG in clinical populations such as Parkinson's disease and chronic conditions, evidence regarding the reliability and validity of the L Test in healthy geriatric individuals is lacking. This study aims to address this gap by evaluating the psychometric properties of the L Test in older adults. Purpose: The purposes of the study are to: Evaluate the test-retest reliability of the L Test in geriatric individuals. Determine its concurrent validity by examining relationships with TUG and 10MWT. Calculate measurement error indices including Standard Error of Measurement (SEM) and Minimal Detectable Change (MDC). Hypotheses H1: The L Test is a valid assessment tool for older adults. H2: The L Test demonstrates acceptable test-retest reliability (ICC ≥ 0.70). H3: The L Test shows a strong correlation with TUG (r ≥ 0.50). H4: The L Test shows a strong correlation with 10MWT (r ≥ 0.50). Study Design: A cross-sectional methodological study with repeated measures (test-retest) one week apart. Participants: Target population: Adults aged ≥65 years who can independently ambulate at least 10 meters. Sample size: 58 participants based on power analysis; increased to 70 to compensate for potential attrition. Sampling: Simple random sampling. Inclusion Criteria: ≥65 years of age Mini-Mental State Examination ≥24 Able to walk 10 meters independently Voluntary participation Exclusion Criteria: Lower limb surgery within the past 6 months Diagnosed cardiovascular, neurological, or pulmonary disease Visual or auditory impairments affecting test safety Procedures Participants will complete: L Test, Timed Up and Go Test (TUG), 10-Meter Walk Test (10MWT; normal and fast speed). One week later, all assessments will be repeated under the same conditions. Outcome Measures: Primary: L Test time (seconds) Secondary:TUG time, 10MWT time (normal and fast pace), SEM and MDC values. Pearson correlation with TUG and 10MWT Statistical Analysis: Test-retest reliability: ICC Concurrent validity: Pearson correlation coefficient Measurement error: SEM, MDC Significance level: p \< 0.05 Ethical Considerations: All tests conducted by trained physiotherapists. Continuous supervision to minimize fall risk. Written informed consent obtained. Participants may withdraw at any time. Confidentiality ensured Expected Outcomes: The study is expected to: Provide normative data for the L Test in the geriatric population Demonstrate the test's psychometric robustness Support the clinical use of the L Test for functional mobility screening Contribute to physiotherapy and geriatric rehabilitation literature