Person misfit on the Inventory of Depressive Symptomatology: Low quality self-report or true atypical symptom profile?

Person misfit on the Inventory of Depressive Symptomatology: Low quality self-report or true atypical symptom profile?

Person misfit on a self-report measure refers to a response pattern that is unlikely given a theoretical measurement model. Person misfit may reflect low quality self-report data, for example due to random responding or misunderstanding of items. However, recent research in the context of psychopathology suggests that person misfit may reflect atypical symptom profiles that have implications for diagnosis or treatment. We followed-up on Wanders et al. (Journal of Affective Disorders, 180, 36-43, 2015) who investigated person misfit on the Inventory of Depressive Symptomatology (IDS) in the Netherlands Study of Depression and Anxiety (n = 2,981). Our goal was to investigate the extent to which misfit on the IDS reflects low-quality self-report patterns and the extent to which it reflects true atypical symptom profiles. Regression analysis showed that person misfit related more strongly to self-report quality indicators than to variables quantifying theoretically-derived atypical symptom profiles. A data-driven atypical symptom profile explained most variance in person misfit, suggesting that person misfit on the IDS mainly reflects a sample- and questionnaire-specific atypical symptom profile. We concluded that person-fit statistics are useful for detecting IDS scores that may not be valid. Further research is necessary to support the interpretation of person misfit as reflecting a meaningful atypical symptom combination.

Satisficing in Mental Health Care Patients: The Effect of Cognitive Symptoms on Self-Report Data Quality

Respondents may use satisficing (i.e., nonoptimal) strategies when responding to self-report questionnaires. These satisficing strategies become more likely with decreasing motivation and/or cognitive ability (Krosnick, 1991). Considering that cognitive deficits are characteristic of depressive and anxiety disorders, depressed and anxious patients may be prone to satisficing. Using data from the Netherland’s Study of Depression and Anxiety (N = 2,945), we studied the relationship between depression and anxiety, cognitive symptoms, and satisficing strategies on the NEO Five-Factor Inventory. Results showed that respondents with either an anxiety disorder or a comorbid anxiety and depression disorder used satisficing strategies substantially more often than healthy respondents. Cognitive symptom severity partly mediated the effect of anxiety disorder and comorbid anxiety disorder on satisficing. The results suggest that depressed and anxious patients produce relatively low-quality self-report data—partly due to cognitive symptoms. Future research should investigate the degree of satisficing across different mental health care assessment contexts.