Table 3. Mental health question items by headache status.
| Item | Mental Health Question | No Headache | Headache | T value |
| cl. | Not been able to concentrate on whatever you’re doing? | 2.04 | 2.13 | -1.06 |
| c2. | Lost much sleep over worry? | 2.14 | 2.11 | 0.27 |
| c3. | Felt that you are not playing a useful part in things? | 1.97 | 2.07 | -1.25 |
| c4. | Felt in capable of making decisions about things. | 1.83 | 2.03 | -2.31* |
| c5. | Felt constantly under strain? | 2.31 | 2.27 | 0.43 |
| c6. | Felt you couldn’t overcome your difficulties? | 2.04 | 2.16 | -1.10 |
| c7. | Not been able to enjoy your normal day-to-day activities? | 1.96 | 2.10 | -1.73 |
| c8. | Not been able to face up to your problems? | 1.94 | 2.28 | -4.0** |
| c9. | Been feeling unhappy and depressed? | 2.01 | 1.99 | 0.22 |
| c10. | Been losing confidence in yourself? | 1.80 | 1.99 | -1.79 |
| c11. | Been thinking about yourself as a worthless person? | 1.55 | 1.88 | -3.31** |
| c12. | Not been feeling reasonably happy, all things considered? | 1.95 | 2.02 | -0.93 |
* p<0.05
** p<0.01