Background: Few studies have addressed health-related quality of life in community-dwelling individuals aged 80 years and above and very few self-assessment quality of life questionnaires have been formally validated in these populations. This study aimed to validate a French version of the LEIPAD, a self-administered questionnaire assessing the health-related quality of life of people aged 80 years and over.
Method: A cross-sectional study of people aged 80 years and over living at home in France was conducted. All subjects recruited were sent a letter explaining the study and requesting their consent to take part. Those who accepted then received the questionnaires, including the LEIPAD, which assesses health-related quality of life in the subjects aged 65 years and above. We assessed its psychometric properties: data completeness, score distribution, floor and ceiling effects, internal consistency, item-total correlations, inter-scale correlations, reliability and convergent validity with the Medical Outcome Study Short-Form 36 (SF-36).
Results: The results obtained from 184 older people (mean age of 83.9 years, standard deviation 3.3) showed very good acceptability (missing data between 1.1% and 11.4% for LEIPAD scales) Factor analysis of the instrument confirmed the multi-dimensional structure in seven independent scales similar to the original version. Good internal consistency (Cronbach's alpha ranging from 0.68 to 0.87) and strong test-retest reliability of the LEIPAD scales (intraclass correlation coefficients ranging from 0.77 to 0.95) were found. Convergent validity with the SF-36 showed moderate to strong correlations, consistent with the hypotheses stated.
Conclusions: The validation of this specific questionnaire will make it possible to investigate individually the health-related quality of life of French older people living at home and will enable French-speaking investigators to contribute to national and international research projects.