Living Conditions, Interviewer Effects and Perceived Well-Being of the Elderly. A Multiple Correspondence Analysis Approach.

Germa Coenders, Ferran Casas, Joan Manuel Batista-Foguet, and Monica Gonzalez

Abstract

This paper reports on a study on quality of life of elderly people carried out in the city of Girona (Spain) in 1999. The study of the quality of life of the elderly must be based on both objective and subjective indicators along a set of relevant sub-dimensions. Most of the relevant factual and subjective items in quality of life questionnaires are qualitative and call for a multiple correspondence type of analysis. Besides, most of the questions are to some extent sensitive and therefore prone to high non-response and interviewer effects.

In this paper, drawing on the work of Escofier (1981) and Zarraga and Goitisolo (1999), we apply a variant of multiple correspondence analysis that can be implemented with ordinary principal component analysis software and that prevents non-response categories from having too high a contribution on the first dimensions. Subjective well-being questions play the role of active variables and objective well-being questions that of illustrative variables. Next, analysis of variance models are fitted to the axis scores with the interviewer and demographic variables used as predictors. Interviewer effect estimates are used to partial interviewer effects out of the axis scores.

The results show a two-dimensional solution to be appropriate. The upper right quadrant corresponds to high quality of life and the lower left quadrant to low quality of life. The solution is related in the expected way to many of the objective illustrative variables such as neighbourhood, prior occupation, income source, disablement, education, level of physical activity and housing condition.

The analysis was replicated without accounting for non-response and interviewer effects and the interpretation of the axes became much less clear.