Italian version of Cancer Dyspnea Scale: cultural-linguistic and clinical validation in patients with advanced cancer disease in palliative care settings

Context: The Cancer Dyspnea Scale (CDS) is a self-reported multidimensional tool used for the assessment of dyspnea, a subjective experience of breathing discomfort, in cancer patients. The scale describes dyspnea using three distinct factors: physical, psychological and discomfort at rest. Objective: to cross-cultural validate the Italian version of CDS (CDS-IT) and examine its content validity, feasibility, internal consistency and construct validity in patients with advanced cancer. Methods: A cross-sectional study was conducted. CDS-IT was forward-backward translated, and its content was validated among a group of experts. Cronbach's α coefficients was used to assess the internal consistency. Construct validity was examined in terms of structural validity through confirmatory factor analysis and convergent validity with Dyspnea Visual Analogue Scale (VAS-D) through the Pearson's correlation coefficient (r). Cancer Quality of life (EORTC QLQ-C15-PAL) and Italian Palliative Outcome Scale (IPOS) were also tested. Results: The CDS-IT was cross-cultural validated and showed satisfactory content validity. A total of 101 patients (mean age: 76 (SD 12), 53% of female) were recruited in palliative care settings. CDS-IT reported a good internal consistency in the total score and its factors (α=0.74-0.83). The factor analysis corresponded acceptably, but not completely with the original study. CDS-IT strongly correlated with VAS-D (r=0.68) and moderately with IPOS and EORTC QLQ-C15-PAL (r=0.33-0.36, respectively). Conclusions: The study findings supported the cross-cultural validity of the CDS-IT. Its feasibility, internal consistency and construct validity are satisfactory for clinical practice. The CDS-IT is available to healthcare professionals as a useful tool to assess dyspnea in cancer patients. Keywords: Advanced disease; Cancer Dyspnea Scale; Dyspnea; Palliative care; Psychometric properties.