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Is quality of life a useful concept for companion animals?

Published online by Cambridge University Press:  11 January 2023

KD Taylor  and
DS Mills
KD Taylor
Affiliation:
Animal Behaviour, Cognition and Welfare Group, Department of Biological Sciences, University of Lincoln, Riseholme Park, Lincoln LN2 2LG, UK
DS Mills*
Affiliation:
Animal Behaviour, Cognition and Welfare Group, Department of Biological Sciences, University of Lincoln, Riseholme Park, Lincoln LN2 2LG, UK
*
* Correspondence: dmills@lincoln.ac.uk
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Abstract

Although the term ‘quality of life’ (QoL) is not unfamiliar to veterinary surgeons, only recently has the scientific community attempted to measure it in farm and companion animals. Typically such studies have applied methodologies from the field of human health-related quality of life (HRQoL), without due consideration of the applicability of both the term and its measurement to animals. However, it is necessary to clarify the philosophical basis of QoL if it is to be defended as a rigorous and reliable aid to decision-making in animal welfare science. In this paper we review common concepts in human HRQoL and discuss the value of, and difficulties regarding, the transfer of the concept of human HRQoL to companion animals. Human definitions tend to focus on individuals and their assessment of the state of their life in terms of physical, social and psychological functioning. The use of the term ‘quality of life’ for animals may therefore expand on what is usually considered when using the term ‘welfare’, and thereby improve on current practice, which tends to focus on relatively few outcome measures that are largely indicative of poor welfare. However, failure in the human literature to properly define QoL and defend the choice of measures accordingly, together with the common use of objective indicators and proxies, has led to confusion over the relative roles of objective and subjective measures in the determination and constitution of QoL. A suggestion for an appropriate definition of animal QoL that clarifies these relationships is offered, together with a list of social/environmental and physical/psychological health-related domains that may be suitable for a generic companion animal QoL assessment tool. In the absence of knowledge on both basic needs and individual preferences, particularly for institutionalised animals, QoL tools may be more appropriately designed as outcome-based tools, focussing on observable signs of health and behaviour. The extent to which recent QoL assessment tools for companion animals have covered these domains, and the extent to which the psychometric properties of the tools have been addressed, is also briefly discussed.

Keywords

animal welfareassessmentbehaviourcompanion animalhuman health-related quality of lifequality of life
Type
Research Article
Information
Animal Welfare , Volume 16 , Issue S1: Quality of Life: the heart of the matter: Proceedings of the UFAW/BVA Ethics Committee International Symposium, The Royal Society, London, 13-14 September 2006. , May 2007 , pp. 55 - 65
Copyright
© 2007 Universities Federation for Animal Welfare

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