Table 3 The performance of different PHQ-9 cut-off scores in detecting depression
From: The validity and reliability of the PHQ-9 in screening for post-stroke depression
Score | Sensitivity (%) (95% CI) | Specificity (%) (95% CI) | Positive predictive value (%) (95% CI) | Negative predictive value (%) (95% CI) | Positive likelihood ratio (95% CI) | Negative likelihood ratio (95% CI) | Accuracy (95% CI) | Youden’s index |
|---|---|---|---|---|---|---|---|---|
The algorithm-based diagnosis | ||||||||
≥ 10 | 34.8 (16.4, 57.3) | 97.8 (92.4, 99.7) | 80.0 (47.6, 94.6) | 85.7 (81.6, 89.0) | 16.0 (3.6, 70.3) | 85.7 (81.6, 89.0) | 85.2 (77.4, 91.2) | – |
The summed-item-based diagnosis | ||||||||
≥ 5 | 91.3 (71.9, 98.9) | 65.2 (54.6, 74.8) | 39.6 (32.6, 47.2) | 96.8 (88.8, 99.1) | 2.62 (1.9, 3.6) | 0.13 (0.04, 0.5) | 70.4 (61.2, 78.6) | 0.565 |
≥ 6 | 87.0 (66.4, 97.2) | 75.0 (64.9, 83.4) | 46.5 (37.1, 56.2) | 95.8 (88.8, 98.5) | 3.5 (2.4, 5.1) | 0.2 (0.1, 0.5) | 77.4 (68.6, 84.7) | 0.620 |
≥ 7 | 78.3 (56.3, 92.5) | 81.5 (72.1, 88.8) | 51.4 (39.6, 63.1) | 93.8 (87.3, 97.0) | 4.2 (2.6, 6.8) | 0.3 (0.1, 0.6) | 80.9 (72.5, 87.6) | 0.598 |
≥ 8 | 65.2 (42.7, 83.6) | 83.7 (74.5, 90.6) | 50.0 (36.6, 63.4) | 90.6 (84.5, 94.4) | 4.0 (2.3, 6.9) | 0.42 (0.2, 0.7) | 80.0 (71.5, 86.9) | 0.489 |
≥ 9 | 56.5 (34.5, 76.8) | 90.2 (82.2, 95.4) | 59.1 (41.4, 74.7) | 89.3 (83.8, 93.0) | 5.8 (2.8, 11.8) | 0.5 (0.3, 0.8) | 83.5 (75.4, 89.7) | 0.467 |
≥ 10 | 52.2 (30.59, 73.2) | 94.6 (87.7, 98.2) | 70.6 (48.4, 85.9) | 88.8 (83.7, 92.4) | 9.6 (3.7, 24.5) | 0.5 (0.3, 0.8) | 86.1 (78.4, 91.8) | 0.467 |