Abstract
Background: Health-related quality of life is measured to detect the influence of lymphedema on physical, functional, and social aspects of life in patients with breast cancer-related lymphedema (BCRL).
Objective: This study aimed to perform the psychometric evaluation of the Lymphedema Life Impact Scale (LLIS) in Turkish patients with BCRL.
Methods: Patients with BCRL (n = 78) filled out the Turkish LLIS, Lymphedema Quality of Life, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30, and Quick Disability of Arm, Shoulder and Hand scales. Breast cancer survivors without BCRL (n = 35) completed only the Turkish LLIS. Psychometric properties were analyzed with the internal consistency, test-rest reliability, construct, criterion, and discriminant validity.
Results: The internal consistency of the Turkish LLIS was strong (Cronbach's [alpha] coefficient >.70). Test-retest reliability was strong to very strong (intraclass correlation coefficients from 0.88 to 0.93; P < .001). Similar to the original structure of the scale, exploratory factor analysis identified 3 factors. Criterion validity was supported by moderate to strong correlations between the LLIS, Lymphedema Quality of Life, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30, and quick Disability of Arm, Shoulder and Hand. There were significant differences in the total and subscale scores of the LLIS between participants with and without BCRL (P < .05).
Conclusions: The present study provided the evidence to confirm reliability and clinical validity of the Turkish LLIS.
Implications of Practice: The Turkish LLIS is a reliable and valid condition-specific scale to measure the physical, functional, and psychological aspects of health-related quality of life in patients with BCRL.