title: The happiness syndrome: methodological and substantive issues in the study of social-psychological well-being in adulthood.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D003430:Cross-Sectional Studies; D006240:Happiness; D006801:Humans; D008137:Longitudinal Studies; D008875:Middle Aged; D010549:Personal Satisfaction; D011788:Quality of Life; D012107:Research Design; D014481:United States