Beyond Linearity: Exploring the Curvilinear Association Between Conscientiousness and Well-Being through Instrument Sensitivity

Background: Recent research has begun to challenge the traditional view of conscientiousness as solely beneficial, suggesting a potential reverse-U-shaped relationship with subjective well-being (SWB). Yet, while some studies have found this curvilinear association, overall findings remain inconsistent. This study proposes the limited conceptualization and measurement of conscientiousness within conventional five-factor model (FFM) personality scales as a contributing factor to the inconsistencies. I compare a conventional FFM (IPIP-120) and a more comprehensive instrument (PID-5) to assess their ability to detect curvilinearity in the conscientiousness-SWB relationship. Method: The study involved comparing linear and curvilinear structural equation models (N = 541) and the significance of linear and curvilinear paths estimated for conscientiousness measured with either the conventional or comprehensive instrument in predicting SWB. Results: The comprehensive instrument did not improve fit of the curvilinear model between conscientiousness and SWB compared to the conventional instrument, suggesting sufficiency of the conventional instrument in describing the nature of this relationship. Discussion: Results did not identify a curvilinear relationship between conscientiousness and SWB, and this pattern held even with a more comprehensive instrument. Still, the study highlights the potential utility of a more comprehensive instrument for measuring conscientiousness. Future research employing such instruments could further refine our understanding of the conscientiousness–SWB link. Conclusion: Clarifying the nature and effects of extreme conscientiousness within the context of maladaptive personality is crucial to address the field's current inconsistencies.