Table 2.
Content Validity Index of Hospital Anxiety and Depression Scale items
| Giving rating of 3 or 4 out of eight experts (n) | I-CVI/average | pc* | K*† | Interpretation‡ | |
| I feel tense or 'wound up’. | 8 | 1 | 0.004 | 1.00 | Excellent |
| I get a sort of frightened feeling, like 'butterflies' in the stomach. | 8 | 1 | 0.004 | 1.00 | Excellent |
| I get a sort of frightened feeling as if something awful is about to happen. | 8 | 1 | 0.004 | 1.00 | Excellent |
| I feel restless as I have to be on the move. | 6 | 0.75 | 0.109 | 0.72 | Good |
| Worrying thoughts go through my mind. | 8 | 1 | 0.004 | 1.00 | Excellent |
| I get sudden feelings of panic. | 8 | 1 | 0.004 | 1.00 | Excellent |
| I can sit at ease and feel relaxed. | 7 | 0.88 | 0.031 | 0.88 | Excellent |
| Anxiety (S-CVI/average: 0.947) | |||||
| I feel as if I am slowed down. | 8 | 1 | 0.004 | 1.00 | Excellent |
| I still enjoy the things I used to enjoy. | 7 | 0.88 | 0.031 | 0.88 | Excellent |
| I have lost interest in my appearance. | 8 | 1 | 0.004 | 1.00 | Excellent |
| I can laugh and see the funny side of things. | 7 | 0.88 | 0.031 | 0.88 | Excellent |
| I look forward with enjoyment to things. | 7 | 0.88 | 0.031 | 0.88 | Excellent |
| I feel cheerful. | 8 | 1 | 0.004 | 1.00 | Excellent |
| I can enjoy a good book or radio or TV programme. | 8 | 1 | 0.004 | 1.00 | Excellent |
| Depression (S-CVI/average: 0.948) | |||||
*: pc (probability of a chance occurrence) was computed using the formula: pc = [N!/A! (N−A)!] × 0.5N, where N=number of experts and A=number agreeing on good relevance.
†k*: kappa designating agreement on relevance: k*=(I−CVI_pc)/(1_pc).
‡: Evaluation criteria for kappa using guidelines described in Cicchetti (1984)35
I-CVI, Item-Level Content Validity Index; S-CVI, Scale-Level Content Validity Index.