Table 3.
Estimated graded response model (GRM) parameters of the items of the BDI-II (N = 12,677).
| Item | a | (SE) | b1 | (SE) | b2 | (SE) | b3 | (SE) |
|---|---|---|---|---|---|---|---|---|
| 1. Sadness | 2.38 | (0.06) | 1.10 | (0.05) | 2.75 | (0.12) | 3.13 | (0.15) |
| 2. Pessimism | 2.20 | (0.05) | 1.12 | (0.05) | 2.57 | (0.09) | 3.35 | (0.16) |
| 3. Past failure | 2.04 | (0.05) | 1.32 | (0.05) | 1.98 | (0.07) | 3.41 | (0.14) |
| 4. Loss of pleasure | 2.27 | (0.05) | 0.95 | (0.05) | 2.34 | (0.08) | 3.25 | (0.15) |
| 5. Guilty feelings | 1.72 | (0.04) | 0.75 | (0.03) | 2.96 | (0.08) | 3.78 | (0.13) |
| 6. Punishment feelings | 1.74 | (0.05) | 1.46 | (0.05) | 2.39 | (0.07) | 2.63 | (0.07) |
| 7. Self-dislike | 2.86 | (0.07) | 1.24 | (0.07) | 1.60 | (0.09) | 2.54 | (0.14) |
| 8. Self-criticalness | 1.62 | (0.03) | 0.25 | (0.03) | 1.78 | (0.04) | 3.24 | (0.08) |
| 9. Suicidal thoughts | 2.12 | (0.07) | 1.89 | (0.08) | 3.22 | (0.15) | 3.60 | (0.19) |
| 10. Crying | 1.52 | (0.04) | 1.16 | (0.03) | 1.93 | (0.04) | 2.73 | (0.06) |
| 11. Agitation | 1.59 | (0.04) | 0.83 | (0.03) | 2.90 | (0.06) | 3.19 | (0.08) |
| 12. Loss of interest | 2.73 | (0.06) | 0.89 | (0.05) | 2.26 | (0.11) | 2.87 | (0.15) |
| 13. Indecisiveness | 2.03 | (0.04) | 0.78 | (0.04) | 1.88 | (0.06) | 2.12 | (0.06) |
| 14. Worthlessness | 3.31 | (0.09) | 1.31 | (0.10) | 1.80 | (0.12) | 2.72 | (0.20) |
| 15. Loss of energy | 2.35 | (0.05) | 0.40 | (0.04) | 1.96 | (0.07) | 3.05 | (0.13) |
| 16. Changes in sleep | 1.58 | (0.03) | 0.03 | (0.03) | 1.69 | (0.04) | 3.04 | (0.07) |
| 17. Irritability | 2.13 | (0.04) | 0.65 | (0.04) | 2.10 | (0.07) | 2.93 | (0.11) |
| 18. Changes in appetite | 1.40 | (0.03) | 0.48 | (0.03) | 2.31 | (0.04) | 3.28 | (0.07) |
| 19. Concentration difficulty | 2.07 | (0.04) | 0.57 | (0.03) | 1.60 | (0.05) | 2.84 | (0.09) |
| 20. Tiredness or fatigue | 2.24 | (0.04) | 0.32 | (0.03) | 1.75 | (0.06) | 2.52 | (0.09) |
| 21. Loss of interest in sex | 1.32 | (0.04) | 1.91 | (0.04) | 3.26 | (0.07) | 4.44 | (0.12) |
a is the discrimination parameter; the bi are location parameters; SE is standard error of the parameter estimate.