Table 2 Mean score, standard deviation, and internal reliability score for each PHQ-9 score
From: The validity and reliability of the PHQ-9 in screening for post-stroke depression
PHQ-9 items | Mean | Standard deviation | Corrected item-total correlation | Cronbach’s alpha if item deleted |
|---|---|---|---|---|
1. Little interest or pleasure in doing things | 0.72 | 0.881 | 0.612 | 0.708 |
2. Feeling down, depressed, or hopeless | 0.64 | 0.926 | 0.516 | 0.723 |
3. Trouble falling or staying asleep, or sleeping too much | 1.11 | 1.256 | 0.404 | 0.749 |
4. Feeling tired or having little energy | 0.68 | 0.984 | 0.321 | 0.755 |
5. Poor appetite or overeating | 0.47 | 0.955 | 0.199 | 0.773 |
6. Feeling bad about yourself – or that you are a failure | 0.71 | 1.015 | 0.612 | 0.704 |
7. Trouble concentrating on things | 0.27 | 0.641 | 0.345 | 0.749 |
8. Moving or speaking so slowly that other people have noticed | 0.35 | 0.731 | 0.555 | 0.722 |
9. Thoughts that you would be better off dead or of hurting yourself | 0.25 | 0.662 | 0.525 | 0.729 |