What’s in the Scales? A Systematic Review of Content Overlap in Well-being and Quality of Life Scales for Older Persons

Objectives: To systematically review and analyse the content of scales used to measure well-being and quality of life (QoL) among older persons. Secondary aims were to examine content overlaps between scales developed specifically for older persons (age-specific) and age-generic scales psychometrically evaluated in older populations, as well as between positively and negatively worded items and between scales targeting well-being and QoL.Methods: A literature search was conducted in PubMed, PsycInfo, and CINAHL. Items from included scales were categorised using a framework for well-being and QoL scales. Descriptive statistics illustrate the content distribution, and Jaccard index estimates content overlap.Results: A total of 744 items from 35 scales were included. Among the age-specific scales for older persons (n =19), the most common dimensions were personal circumstances, personal relationships, and physical health. For age-generic scales (n =16), activities and functioning, personal relationships, and self-acceptance were most prominent. Average content overlap was 0.42 (range 0.22–0.55) for age-specific scales, indicating moderate overlap.Conclusion: While there is some consistency in content across age-specific well-being and QoL scales for older persons, notable heterogeneity remains. In addition, this study sheds light on the operational similarities and distinctions between scales aimed at generic and older populations.