VALIDATION OF THE LYMPHEDEMA LIFE IMPACT SCALE (LLIS): A CONDITION-SPECIFIC MEASUREMENT TOOL FOR PERSONS WITH LYMPHEDEMA

Abstract

Evidence-based practice supports the useof validated outcome measures to assess theimpact of lymphedema; however, conditionspecificlymphedema assessment measures areneeded. The Lymphedema Life Impact Scale(LLIS) was developed as a comprehensive,lymphedema-specific instrument to assessthe effects of lymphedema in any extremity.The LLIS is an 18-item measure of physical,psychosocial, and functional impairmentscaused by lymphedema. The purpose of thismulticenter, cross sectional study was toinvestigate the reliability and validity of theLLIS. Test-retest reliability was assessed ina subgroup of 17 participants. Internalconsistency and validity was assessed in 71participants with upper (nUE = 37) or lowerlimb (nLE = 34) lymphedema, and a controlgroup of 31 participants without lymphedema.Intraclass correlation coefficients fortest-retest reliability ranged from .965 to .990.Cronbach’s alpha coefficients for internalconsistency ranged between .841 and .926.Construct validity of the LLIS was upheldwith symptoms, but not with edema severity.The LLIS correlated highly with other comparisonmeasures used in this study. Minimalclinically important difference of the LLISwas 7.31; MDC95 = 11.53. Our results showedthe LLIS to be a valid and reliable tool for theassessment of severity of impairment amongpatients with lymphedema.