Validation and norms in health status instruments in older people: The Islington Study

Background

Health related quality of life scales have been developed to measure a global picture of health and well-being from the patient's perspective. Separate validation of these measures in older people is important, as different areas of life are prioritized as important in older people and population norms for health status measures can differ with age.

Objectives

The aims of this paper were to examine the validity and acceptability of two health status measures the 12-item Health Status Questionnaire (HSQ-12) and 12-item Short Form Health Survey SF-12, and to present population norms in older people.

Setting

A door-to-door survey in Islington, a borough of inner London.

Subjects and methods

The subjects were allocated to complete either the SF-12 (n = 541) or the HSQ-12 (n = 544) by alternating the questionnaires with each household visited. The first 135 people who completed the HSQ-12 were visited approximately 18 months later. Acceptability was measured examining the completion rate of the scales, and on a three-point scale. The short-CARE was used to elicit psychiatric symptoms and diagnoses. We collected data on health and social care, and subjective health problems.

Results

Both scales distinguished between subjects with and without a variety of health states, including self-defined health problems, health problems diagnosed by valid scales, problems with vision and hearing, and receipt of health or social services. The HSQ-12, but not the SF-12, could distinguish between people with and without dementia, and had high completion rates for those living in the community but not in 24-hour care. Linear regression models demonstrated sensitivity to change in health status for the HSQ-12.

Conclusion

The SF-12 and HSQ-12 are acceptable and valid as health status instruments in large community-based studies of older people. The HSQ-12, but not the SF-12, is acceptable and valid for people with dementia. Copyright © 2001 John Wiley & Sons, Ltd.