BackgroundAcute and late toxicities in patients treated with (chemo)radiotherapy for head and neck cancer (HNC) is common and can negatively impact quality of life and performance. Performance status instruments measure the functional ability to perform daily life activities and are important tools in the oncologic population. AimsSince Dutch performance status scales for the HNC population are lacking, we conducted this study to translate the Performance Status Scale for Head and Neck Cancer Patients (PSS-HN) into Dutch (D-PSS-HN) and to validate this version. Methods & ProceduresThe D-PSS-HN was translated into Dutch according to the internationally described cross-cultural adaptation process. It was administered to HNC patients and together with the Functional Oral Intake Scale completed by a speech and language pathologist at five different time points during the first 5 weeks of (chemo)radiotherapy. Patients were asked each time to complete the Functional Assessment of Cancer Therapy and the Swallowing Quality of Life Questionnaire. Pearson correlation coefficients were used to calculate convergent and discriminant validity and the evolution of D-PSS-HN scores was assessed by means of linear mixed models. Outcomes & ResultsA total of 35 patients were recruited and > 98% of the clinician-rated scales were completed. Convergent and discriminant validity were demonstrated, with all correlations r(s) between 0.467 and 0.819, and between 0.132 and 0.256, respectively. The subscales of the D-PSS-HN are sensitive to detect changes through time. Conclusion & ImplicationsThe D-PSS-HN is a valid and reliable instrument to assess performance status in patients with HNC treated with (chemo)radiotherapy. It is a useful tool to measure HNC patients' current diet level and functional abilities to perform daily life activities. WHAT THIS PAPER ADDSWhat is already known on the subjectAcute and late toxicities in patients treated with (chemo)radiotherapy for HNC are common and can negatively impact quality of ...