Validation of Subjective Well-Being Measures Using Item Response Theory

Area of Science:

• Psychology
• Psychometrics
• Well-being Research

Background:

• Subjective well-being (SWB) is a key indicator of life quality, encompassing affective and cognitive evaluations.
• Recent research includes a social context dimension: harmony in life.
• Traditional validation of SWB self-report measures often relies on Classical Test Theory.

Purpose of the Study:

• To evaluate the psychometric properties of SWB measures using Item Response Theory (IRT).
• To assess the unidimensionality and validity of affective, cognitive, and social SWB scales.
• To identify specific items for improvement to enhance measurement reliability.

Main Methods:

• 1000 participants completed the Positive Affect Negative Affect Schedule (PANAS).
• Half of participants also completed the Satisfaction with Life Scale (SWLS) or the Harmony in Life Scale (HLS).
• Graded response models within IRT were used to analyze scale psychometrics and unidimensionality.

Main Results:

• All scales demonstrated varied item distributions, high discrimination (Alphas), and distinct difficulty parameters (Betas).
• Measurement ranges (Theta) varied across scales, indicating coverage of different SWB levels.
• Reliability was notably weaker for participants with extreme latent SWB scores across all scales.

Conclusions:

• The affective component, particularly low negative affect, showed lower measurement accuracy.
• Cognitive (SWLS) and social (HLS) components were measured with comparable accuracy.
• Specific items require modification or addition to improve reliability at item and scale levels, especially for extreme scores.