Comparison of mean symptom counts (using different measures) between ‘unexplained’ cases and ‘explained’ controls
| Maximum symptom count score | Number of patients | Mean symptoms count (95% CI) | t Statistic | p Value | |||
|---|---|---|---|---|---|---|---|
| Unexplained* | Explained† | Unexplained* | Explained† | ||||
| PHQ-15‡ | 13 | 1136 | 2627 | 5.6 (5.4 to 5.8) | 4.2 (4.1 to 4.4) | 12.5 | <0.0001 |
| PHQ-15+10 neurological symptoms | 23 | 1125 | 2613 | 8.5 (8.3 to 8.8) | 6.8 (6.6 to 6.9) | 10.9 | <0.0001 |
| PHQ-15+10 neurological symptoms+5 PRIME MD symptoms | 28 | 1124 | 2610 | 10.7 (10.3 to 11.0) | 8.4 ( 8.2 to 8.6) | 11.4 | <0.0001 |
*Unexplained=Not at all explained/Somewhat explained by disease.
†Explained=Largely explained/Completely explained by disease.‡PHQ-15=the maximum score is 13 as the 2 items on sexual problems and menstrual difficulties were removed.
PHQ, Patient Health Questionnaire.