As the older adult population increases globally, it is important for local governments to measure their health and well-being consistently to effectively support this group. Because definitions of subjective well-beingsuch as happiness, life satisfaction and subjective healthoverlap, it is worth considering which single-item indicator local governments can rely on to measure individual well-being. This study, therefore, explored the correlation between three single-item questionnaires on happiness, life satisfaction and subjective health used in government surveys, and established psychometric scales of happiness, life satisfaction and quality of life, and analyzed which of the three single-item indicators most effectively captured the target well-being.Methods: Randomly selected people aged ≥65 years in urban and rural areas (n = 1440) answered the questions on the Happiness Scale, the Satisfaction with Life Scale and the Quality of Life scale, and the three single-item questionnaires (happiness, life satisfaction and subjective health). We analyzed the data using correlation and multiple regression analyses.
Results:The results showed a high positive correlation between the scales and the singleitem questionnaires. The single-item life satisfaction and subjective health questionnaires were significantly correlated with all the three scales. Although there was not much difference in the adjusted R 2 values between putting three items jointly and separately, the value of single-item life satisfaction was the best and the subjective health was the second best.
Conclusion:The results showed that the single-item life satisfaction and subjective health effectively captured the target well-being; these could be the appropriate indicators for a potential optimal index.