Quantification choices for individual differences: An example of mapping self-report to psychophysiological responses

Area of Science:

• Affective neuroscience
• Individual differences research
• Psychophysiology

Background:

• Affective neuroscience often examines links between individual differences and psychophysiological responses.
• Few studies demonstrate how quantifying individual differences impacts observed relationships.

Purpose of the Study:

• To investigate how different quantification methods for individual differences influence the relationship between self-reported intolerance of uncertainty (IU) and skin conductance responses.
• To address the gap in practical examples of quantification's impact on observed relationships.

Main Methods:

• A two-stage aggregated meta-analysis was conducted on 18 studies (N=1006).
• Self-reported intolerance of uncertainty (IU) was quantified continuously, categorically (median split), and categorically (extremes).
• Skin conductance responses during threat extinction were analyzed.

Main Results:

• Different quantification techniques yielded both consistent and inconsistent effects of IU on skin conductance.
• Categorical quantification (vs. continuous) was associated with more statistically significant effects and larger effect sizes.
• Higher IU consistently related to increased skin conductance during late extinction training.

Conclusions:

• The quantification method for individual differences can influence study outcomes and effect sizes.
• Employing diverse quantification methods aids in understanding constructs and assessing the reliability of findings.
• This approach helps evaluate the correspondence between different units of analysis in individual differences research.