Modifiers of Health-Related Quality of Life by Biological, Psychological and Social Factors

Healthcare workers, clinicians and/or researchers require information on the consequences of illness on their patients, as well as on the effects associated with treatments, when making decisions on recommended treatments and for follow-up evaluations of the same. Identifying health indicators which provide necessary and appropriate data for the evaluation of clinical outcomes in terms of Health-Related Quality of Life (HRQoL), as established by the WHO Biopsychosocial Model, and which provide appropriate and pertinent information on physical, mental and social factors in patients, can improve decision-making in relation to a comprehensive and global perspective of clinical outcomes of the various treatments and procedures given to patients. This chapter aims to provide an overview of the various tools for assessing Health-Related Quality of Life, as a growing number of clinicians, researchers and patient groups wish for comprehensive and not merely biological measures of health. This may be explained by the growing number of self-administered or interview questionnaires which have the aim of measuring changes in health as well as the consequences of the various treatments used mainly on chronicity and chronic health conditions. During recent decades, numerous tools have been developed and applied to the measurement of the effects of Health-Related Quality of Life in patients based on biological or physical aspects, psychological or mental aspects, and social aspects. This chapter will review the most frequently-used tools for the measurement of Health-Related Quality of Life, and recommendations are made for their use in medical care according to psychometric characteristics and quality criteria, as a guide for use in the field of healthcare, in public health, or in outcomes research.