Disclosing depressive symptoms: perceived sensitivity of PHQ-9 items in a general population sample

The Patient Health Questionnaire-9 (PHQ-9) is one of the most widely used tools for screening and assessing depression. However, previous research has yielded inconsistent results regarding its factor structure, with studies suggesting either a one- or two-factor model. One possible explanation is socially desirable responding (SDR), which may arise if some items are perceived as more sensitive than others. This study examines whether such differences in perceived sensitivity exist and how they correspond to patterns reported in prior factor-analytic research. A total of 273 participants completed 36 paired comparisons of the PHQ-9 items, indicating which symptoms they would find more uncomfortable to disclose. Additionally, absolute judgments were collected, where participants rated each item as either uncomfortable or not uncomfortable to disclose. Data were analyzed using a paired comparisons model rooted in Thurstone’s law of comparative judgment to estimate the relative sensitivity of each item and whether they were more or less likely to be judged as (not) uncomfortable to disclose. Kendall’s coefficients of consistence and agreement were calculated to evaluate the internal consistency of participants’ responses and the level of agreement between them. Results showed that cognitive/affective symptoms, such as feelings of worthlessness and depressed mood were perceived as more sensitive than somatic symptoms like fatigue and sleep disturbances. Notably, the sensitivity estimates obtained in this study align closely with prior factor analytic findings that have supported a two-factor model distinguishing cognitive/affective and somatic symptoms. These findings suggest that social desirability may contribute to the underreporting of certain depression symptoms, potentially helping to explain inconsistencies in the PHQ-9’s factor structure. Researchers and clinicians should consider the impact of SDR when interpreting PHQ-9 scores to enable more accurate assessments of depression symptom severity.