Validity, reliability and clinical utility of the Glittre ADL test in patients with atrial fibrillation

Abstract

Background Activities of daily living (ADL) are frequently impaired in patients with atrial fibrillation (AF). Although the 6-Minute Walk Test (6MWT) is widely used for functional assessment, it primarily evaluates walking endurance and may not fully reflect complex ADL involving upper limb activities and postural changes. This study investigated the validity, reliability and clinical utility of the Glittre ADL test in AF. Methods This cross-sectional study included 39 AF patients and 39 matched healthy controls. All participants completed the Glittre ADL test. Concurrent validity was assessed using the 6MWT. Construct validity was evaluated using peripheral muscle strength, the five-times sit-to-stand test (5STS), Short Form-36, Atrial Fibrillation Impact Questionnaire and Milliken ADL Scale. Test-retest reliability was assessed using the intraclass correlation coefficient (ICC) by repeating the test after 1 hour. Receiver operating characteristic (ROC) analysis was conducted to assess the ability of the Glittre ADL test to discriminate individuals with increased symptom burden based on 6MWT performance; the optimal cut-off was determined using the Youden index. Results AF patients completed the Glittre ADL test significantly slower than healthy controls (198.98 s vs 180.09 s, p<0.05). Test-retest reliability was excellent (ICC=0.914; 95% CI 0.834 to 0.955). Test duration showed a strong negative correlation with 6MWT distance (r=-0.87, p<0.001) and significant correlations with 5STS performance, peripheral muscle strength and physical quality-of-life components (p<0.05). ROC analysis indicated high discriminative ability area under the curve=0.967; 95% CI 0.922 to 1.000), with an optimal cut-off of 196.52 s (sensitivity 100%, specificity 82.6%). Conclusions The Glittre ADL test is valid, reliable and clinically useful for assessing complex ADLs in AF patients. The defined cut-off helps clinicians identify functional impairment.