Abstract
OBJECTIVE: This study aimed to translate and cross-culturally adapt the Fremantle Knee Awareness Questionnaire (FreKAQ) into Brazilian Portuguese and evaluate the measurement properties, including internal consistency, construct validity, reliability, and ceiling and floor effects in individuals with knee osteoarthritis (KOA). METHODS: Translation, cross-cultural adaptation, and analysis of measurement properties were performed according to international recommendations. One hundred thirty-four individuals diagnosed with KOA participated in the study. Of these, 30 participated in the validation process of the pre-final version of the FreKAQ. One hundred four were evaluated with the FreKAQ, the Numeric Pain Rating Scale (NPRS), the Pain Catastrophizing Scale (PCS), the International Knee Documentation Committee (IKDC), and the 36-item short-form survey (SF-36). The construct validity was tested using Spearman's correlation coefficient, and ceiling and floor effects were calculated. A subsample of 54 participants participated in the reproducibility assessment. Internal consistency was calculated using Cronbach's alpha. Reproducibility was assessed using the test-retest model using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimum detectable change (MDC). RESULTS: the FreKAQ showed a favorable correlation with the construct's intensity and catastrophizing related to pain and activities of daily living (p < 0.01). It also had the functional capacity, pain, social aspects, and emotional aspects of the SF-36 (p < 0.05). Additionally, it presented excellent ICC (0.91) and adequate internal consistency (0.91) with the SEM and MDC scores, respectively, 2.86 and 7.94. There were no ceiling or floor effects. CONCLUSION: The FreKAQ showed adequate measurement properties in individuals with KOA, indicating its use as an evaluative measure of body perception of the knee.