Quality of life and outcomes research in head and neck cancer: a review of the state of the discipline and likely future directions.

Quality of life (QOL) is by definition a multi-dimensional global construct that has become an increasingly important outcome measure in cancer treatment. The impact of a head and neck cancer (HNC) diagnosis on the person and the consequences of its treatment cross multiple functional domains that have a clear and direct influence on one's post-treatment well-being and associated QOL. The evaluation of QOL and performance outcome in cancer is critical to optimal patient care, comprehensive evaluation of treatment alternatives, and the development of informed rehabilitation and patient education services. Despite the difficulties of going from concept to quantification of patient perceptions, the number of instruments available to measure QOL psychometrically has increased rapidly. Assessments can now be made in a variety of distinctive ways using both specific and generic measures. There is no gold-standard questionnaire and the choice is based on psychometric properties, research objectives and study design. QOL assessment has evolved over the years into an organised scientific discipline, such that useful insights can be obtained by a review of the current literature. However, more work needs to be done to improve the applicability and clinical utility of QOL assessment. Most importantly, QOL studies should be reported in such a way as to provide clinically meaningful data to physicians and surgeons, in order to link research to clinical practice. Further attention should be paid to the development of newer theoretical models, minimalist approaches, development of more sensitive and specific instruments and the effective use of modern technology to achieve this objective.