Measurement of subjective quality of life of elders.

There are two aims in this article, to define subjective quality of life and to suggest a way to standardize its measurement to enable comparisons to be made across studies. One of the unresolved issues in gerontological research has concerned the definition and measurement of quality of life (Lawton, 1991). This article focuses on subjective well-being, one of the four components proposed by Lawton (1991). There seems to be a growing consensus that most scales of well-being have at least two concepts in common, positive and negative affect. To test this hypothesis, two well-being scales, the Philadelphia Geriatric Center Morale Scale (Lawton, 1975) and the Center for Epidemiological Studies-Depression Scale (Radloff, 1977), were subjected to confirmatory factor analyses, using data on 1717 participants in the Australian Longitudinal Study of Ageing aged between 70 and 103 years. Each scale was shown to contain factors of positive and negative affect. The article concludes with a suggestion that the measurement of quality of life in elders should include, at a minimum, scales of positive and negative affect as well as other measures relevant to the aspect of quality of life under consideration.

The role of self-perceived usefulness and competence in the self-esteem of elderly adults: confirmatory factor analyses of the Bachman revision of Rosenberg's Self-Esteem Scale.

This article reports on a confirmatory analytic study of the Bachman Revision (1970) of Rosenberg's Self-Esteem Scale (1965) that was used in the Australian Longitudinal Study of Ageing (ALSA). Participants comprised 1,087 elderly people aged between 70 and 103 years (mean 77 years). Five competing factor models were tested with LISREL8. The best-fitting model was a nested one, with a General Self-Esteem second-order factor and two first-order factors, Positive Self-regard and Usefulness/Competence. This model was validated with data from a later wave of ALSA. Usefulness and competence have received little attention in the gerontological literature to date. Preliminary results indicate that usefulness/competence may be an important predictor of well-being. Further work is required on the relationships among usefulness, competence, self-esteem, and well-being in elderly people.

The pupillary light reflex cannot be used to measure sleepiness.

The pupillary light reflex (PLR) has been considered by some researchers to be responsive to changes in levels of sleepiness. However, no previous studies have tested this hypothesis with the dramatic variation of sleepiness across a complete circadian cycle. In this experiment, 20 normal individuals (age: 18-48 years) underwent a 27-hr constant routine, during which they were kept awake except for a 15-min nap opportunity every hour. Sleepiness was assessed both subjectively, by the Stanford Sleepiness Scale, and objectively, by a modified version of the Multiple Sleep Latency Test. The PLR in response to a flash of light was recorded every 2 hr, immediately before a nap period. Results showed that baseline pupil diameter became smaller with progressive sleep restriction, but there were no changes in any of the parameters of the PLR despite significant fluctuations in sleepiness. Some of the changes in the PLR were significantly related to changes in baseline pupil diameter. When baseline diameter was partialled out, there was still no effect of sleepiness on the PLR. The results suggest that the PLR cannot be used as a measure of sleepiness.