Optimism and the time-stable component of self-rated health: A threshold-specific latent growth analysis.

OBJECTIVES: Self-rated health (SRH) is a widely used measure of health, but debate persists over how its subjective component should be interpreted. This study tests whether dispositional optimism reflects a time-stable source of subjectivity in SRH or an adaptive evaluative filter through which changing health is interpreted.

DESIGN: Using longitudinal data from the US Health and Retirement Study, 16,902 adults aged 50+ were analysed with threshold-specific latent growth curve models. SRH was modelled across four positive-health thresholds: 'Excellent,' 'Very Good+,' 'Good+' and 'Fair+.' Stable optimism was examined as a predictor of SRH persistence, H1, and as a moderator of health changes, including depressive symptoms, new diagnoses, mobility limitations and ADLs, H2.

RESULTS: Stable optimism significantly predicted higher odds of positive SRH across thresholds per H1. Evidence for H2 was insufficient: optimism did not consistently weaken the association between worsening health and lower odds of positive SRH. SRH remained responsive to depressive symptoms, chronic conditions and functional limitations across thresholds.

CONCLUSION: Optimism contributes to SRH primarily as a stable evaluative anchor rather than as a consistent buffer against health decline. SRH's subjectivity should not be read merely as unreliable; it appears internally structured enough to be interpreted alongside observed health indicators.