Development of a European Organization for Research and Treatment of Cancer (EORTC) questionnaire module to be used in quality of life assessments in head and neck cancer patients. EORTC Quality of Life Study Group - Bjordal, K; Ahlner-Elmqvist, M; Tollesson, E; Jensen, A B; Razavi, D; Maher, E J; Kaasa, S (Acta Oncol, 1994)