Research methodology
Sampling
The data were collected in France, using questionnaires which were self administered to seniors selected randomly in clubs of retired people. The questionnaire was pre-tested on a convenience sample of 20 retired people living in Paris. Then it was administered to groups of retired people. The size of the groups varied from 15 persons down to 52 persons. Each person answered the questionnaire individually. The survey lasted around 20 minutes. A total of 375 questionnaires have been administered. Among these questionnaires, 56 were incomplete (90 per cent of these incomplete questionnaires presented one or several blanks (no answer) on the subjective ages’ items) and 19 presented unacceptable or unreadable answers. Thus, these 75 questionnaires were not used for analysis. Table I outlines the demographic characteristics of the final sample.