What stole Chinese older adults' life satisfaction? Integrating medical statistics and machine learning with a life-course perspective using CHARLS data.

Depressive symptoms and satisfaction with children relationship consistently influence life satisfaction across all satisfaction stages among older Chinese adults.

• These two variables were identified as the only factors with cross-stage consistency across all levels of life satisfaction
• Sample consisted of 4,627 individuals aged 60 and above from the 2020 wave of CHARLS merged with the 2014 Life History Survey
• Both Generalized Ordered Logit Regression and XGBoost confirmed these as dominant predictors
• Their influence persisted from lower to the highest levels of satisfaction

At lower levels of life satisfaction, present-day psychosocial and material conditions play dominant roles.

• Key factors at lower satisfaction levels included depressive symptoms, self-rated health, intergenerational relationships, and access to utilities
• These current-day conditions were identified as the primary determinants distinguishing lower from higher satisfaction groups
• The study used a stage-specific analytical framework to identify these level-specific patterns
• Material conditions such as access to utilities were particularly relevant at lower satisfaction thresholds

Early-life factors become increasingly important as life satisfaction level increases.

• Data on early-life experiences were drawn from the 2014 CHARLS Life History Survey merged with the 2020 wave
• The life-course perspective revealed that accumulated early experiences had greater explanatory power at higher satisfaction levels
• This pattern was identified using a stage-specific framework that assessed predictors across different satisfaction thresholds
• The shift from present-day to early-life determinants represents a gradient across the satisfaction spectrum

The transition to the 'very satisfied' level involves all five domains of predictors simultaneously.

• Five domains of predictors were examined in the integrated analytical framework
• The highest level of satisfaction was explained by a smaller, more specific group of enduring psychological and intergenerational factors
• This contrasts with the transition to 'very satisfied,' which required the full range of predictor domains
• The XGBoost algorithm was used to capture nonlinear associations and variable interactions across these domains

The study found heterogeneity in the determinants of life satisfaction across different satisfaction levels among older Chinese adults.

• Generalized Ordered Logit Regression (GOLR) was combined with XGBoost machine learning to capture both linear and nonlinear associations
• The integrated mixed-method approach enabled identification of key determinants across satisfaction levels while allowing for variable interactions and heterogeneity analysis
• The sample included 4,627 individuals aged 60 and above
• The analytical framework was described as 'stage-specific,' assessing which factors dominate at different points along the satisfaction continuum

Intergenerational relationships, including satisfaction with children relationships, are significant determinants of life satisfaction among older Chinese adults.

• Satisfaction with children relationship was one of only two variables consistently influential across all satisfaction levels
• Intergenerational relationships were identified as a dominant factor particularly at lower satisfaction levels
• The highest level of satisfaction was partly explained by enduring intergenerational factors
• The findings suggest the need for policy interventions incorporating emotional connectedness for those with higher satisfaction

Self-rated health is a dominant factor at lower levels of life satisfaction among older Chinese adults aged 60 and above.

• Self-rated health was grouped among the present-day psychosocial and material conditions dominant at lower satisfaction levels
• It was listed alongside depressive symptoms, intergenerational relationships, and access to utilities as key lower-level determinants
• Data were drawn from the 2020 wave of CHARLS with a sample of 4,627 individuals aged 60 and above
• Its relative importance was identified to diminish compared to early-life factors at higher satisfaction levels