The Meaning and Clinical Implications of Low MMPI-3 Self-Importance Scores

Abstract
The Minnesota Multiphasic Personality Inventory-3 (MMPI-3) includes two self-concept-oriented scales: Self-Doubt (SFD), a measure of low self-esteem, and Self-Importance (SFI), a measure of beliefs that one has special attributes and abilities. Past research has demonstrated that SFD and SFI measure related but distinct constructs. The present study focused on explicating the meaning and clinical implications of low SFI scores. Using three clinical samples (private practice and community mental health and private practice neuropsychology clinics), we investigated whether the presence of interpretable low SFI scores (< 39 T) in the context of interpretable SFD elevations (≥ 65 T) is associated with distinctive MMPI-3 findings, and whether low SFI scores add clinically meaningful information in predicting relevant extra-test criteria. Consistent meaningful findings were obtained with respect to implications of low SFI scores for assessment of depression- and social engagement-related constructs. Additionally, the full range of SFI scores was meaningfully and negatively correlated with depressive disorder diagnoses and suicidal ideation but yielded very small correlations with suicide attempt and nonmeaningful correlations with diagnoses of Social Anxiety or Avoidant Personality Disorder. Hierarchical logistic regression analyses showed that SFI scores could meaningfully increment other related MMPI-3 scales in predicting diagnosed depressive disorders, albeit with small effect sizes.