Table 5.
Relationship Between PHQ-9 Depression Severity Score and Disability Days, Symptom-related Difficulty, and Clinic Visits
| Mean Disability Days (95% CI)* | Symptom-related Difficulty (%)† | Mean Physician Visits (95% CI)* | ||||
|---|---|---|---|---|---|---|
| Level of Depression Severity, PHQ-9 Score | Primary Care | Obstetrics-gynecology | Primary Care | Obstetrics-gynecology | Primary Care | Obstetrics-gynecology |
| Minimal, 1–4 | 2.4 (1.7 to 3.1) | 2.2 (1.7 to 2.7) | 1.5 | 0.6 | 1.0 (0.9 to 1.1) | 0.9a (0.8 to 1.0) |
| Mild, 5–9 | 6.7 (5.5 to 7.8) | 5.8 (4.9 to 6.6) | 10.2 | 4.8 | 1.8a (1.6 to 2.0) | 0.9a (1.0 to 1.4) |
| Moderate, 10–14 | 11.4 (9.5 to 13.1) | 9.9a (8.4 to 11.3) | 24.4 | 16.8 | 2.0a (1.7 to 2.4) | 1.3a (1.0 to 1.6) |
| Moderately severe, 15–19 | 16.6 (14.1 to 19.0) | 10.8a (8.6 to 13.0) | 45.1a | 36.0 | 2.4a (1.9 to 2.8) | 2.3b (1.8 to 2.8) |
| Severe, 20–27 | 28.1 (25.2 to 31.0) | 13.8a (10.8 to 16.7) | 57.1a | 56.6 | 3.7 (3.2 to 4.2) | 2.3b (1.7 to 3.0) |
Disability days refers to number of days in past 3 months that their symptoms interfered with their usual activities. Physician visits refers to past 3 months also. Both are self-report. Means are also adjusted for age, gender, race, education, study site, and number of physical disorders.
Response to single question: “How difficult have these problems made it for you to do your work, take care of things at home, or get along with other people?” The 4 response categories are “not difficult at all,”“somewhat difficult,”“very difficult,” and “extremely difficult.” Report difficulty in this table refers to those patients reporting “very” or “extremely” difficult.
Most pairwise comparisons between each PHQ-9 severity level for a given variable are significant at P < 0.05 using Bonferroni's correction for multiple comparisons. Only those pairwise comparisons that share a common superscript letter (a, b, or a,b) are not significant.