About us

A concern with life quality has driven much of evolution. For any animal, easy access to food and the avoidance of predators, facilitates reproductive fitness. So acquiring the best living environment and life quality has always been competitive. Humans have been exceptionally good at this competition and, around 60,000 years or so ago, our ancestors staged the first successful migration out of Africa. This allowed them to progressively increase their reproductive fitness by finding new habitats, developing agriculture, forming tribes with stable political allegiances, and thereby successfully populating the planet.

Principle:

Quality of Life (QOL) should be defined in a way that is fundamentally at one with evolution. The definition should be applicable to all living things, from bacteria to humans.

Global QOL definition:

‘Quality of life is the extent to which an organism can realise its genetic potential. In this definition, ‘Potential’ refers to the optimal expression of each genotype, and ‘Optimal expression’ refers to maximised reproductive fitness.

While this definition suffices for lower animals, it is inadequate for humans. Their adaptive capacity, coupled with welfare, makes reproductive fitness and inappropriate outcome variable. Human life quality is also a more complex construct than it is for lower animals. Humans have a dual sense of life quality. One is a proximal sense of life quality felt as a personal appraisal of oneself. The other is an appraisal of ones’ distal environment, which can be described as an objective reality.

This leads to the recommended definition:
‘Quality of life is both objective and subjective. Each of these two dimensions comprises several domains which, together, define the total construct. Objective domains are measured through culturally relevant indices of objective wellbeing. Subjective domains are measured through questions of satisfaction’.

Prior to 1976, the few researchers who were measuring how people felt about their lives used various dependent variables. These included, for example, ‘happiness’ (Sweetser, 1850), ‘importance’ (Decker, 1955), and ‘morale’ (Cumming & Henry, 1961). Considering these in chronological sequence:

Happiness:

Campbell, Converse, and Rodgers (1976) discuss the preferred use of happiness or satisfaction in questions requesting a subjective evaluation. Their specific concern is with the most appropriate term when the question moves from a broad domain (e.g. housing) to a more specific component of the domain (e.g. the heating of their home). They note that, “As we move down the ladder of abstraction from global feelings to these more specific assessments, the concept of ‘happiness’ becomes increasingly awkward, while the concept of satisfaction becomes more natural” (p.33). This observation has generally resonated with researchers, and ‘satisfaction’ has become the preferred common term for subjective QOL measurement.

Importance:

It is somewhat intuitive that scales comprising questions of ‘satisfaction’ can be made more personally valid by weighting the satisfaction score for each item by the level of personal importance attributed to that item (I x S). The first researcher to empirically test this was Decker (1955) in relation to a scale of job satisfaction. He found that the weighting failed to change the correlations between the different measures of satisfaction. This failure of (IxS) to improve the statistical performance of (S) alone has since been replicated by numerous researchers (e.g. Ewen, 1967; Trauer & Mackinnon, 2001; Wu & Yao, 2007). In this instance, intuition is incorrect. There is no value in measuring ‘importance’ in addition to ‘satisfaction’.

Morale:

Early researchers into life quality quite commonly use ‘morale’ as a dependent variable. However, its intended meaning is complex. As an example, Viteles (1953) states “Morale is an attitude of satisfaction with, desire to continue in, and willingness to strive for the goals of a particular group or organization” (p.284). It is evident that this definition has many parts and Locke (1976, p. 1300) observes that it differs from the concept of satisfaction in two major ways. First, morale is more future-oriented, while satisfaction is more present and past-oriented. Second, morale often has a group referent, based on a sense of common purpose and the belief that group goals can be attained which are compatible with individual goals. Satisfaction, on the other hand, typically refers to the appraisal made in reference to a single individual.
In summary, asking people how ‘satisfied’ they feel seems the most suitable choice of dependent variable for questions that refer to either abstract or specific QOL topics.

References

Campbell, A., Converse, P. E., & Rodgers, W. L. (1976). The quality of American life: Perceptions, evaluations, and satisfactions. Russell Sage Foundation: New York.

Cumming, E., & Henry, W. E. (1961). Growing Old. New York: Basic Books.

Decker, R. L. (1955). A study of three specific problems in the measurement and interpretation of emoloyee attitudes. Psychological monographs: General and applied, 69(16), Whole number 401.

Ewen, R. B. (1967). Weighting components of job satisfaction. Journal of Applied Psychology, 51(1), 68-73.

Locke, E. A. (1976). The nature and causes of job satisfaction. In M. D. Dunnette (Ed.), Handbook of industrial and organizational psychology (pp. 1297-1349). Chicago: Rand McNally.

Sweetser, W. (1850). Mental Hygiene (Second ed.). New York: George P. Putnam.

Trauer, T., & Mackinnon, A. (2001). Why are we weighting? The role of importance ratings in quality of life measurement. Quality of Life Research, 10, 579-585.

Viteles, M. S. (1953). Motivation and morale in industry. New York: W. W. Norton.

Wu, C. H., & Yao, G. (2007). Importance has been considered in satisfaction evaluation: An experimental examination of Locke’s range-of-affect hypothesis. Social Indicators Research, 81(3), 521-542.