Table 2.
Clustering of ME/CFS cases according to symptom differences, as supported by k-means analysis. Data are presented as the mean ± SD for each item. Physical functioning and bodily pain were evaluated by two items of the 36-item Short-Form Health Survey (SF-36).
| Cluster 1 | Cluster 2 | Cluster 3 | p-Value | |
|---|---|---|---|---|
| Total FIS | 147.93 (9.88) | 131.79 (13.48) | 108.1 (21.83) | <0.0001 |
| Total COMPASS | 66.82 (10.52) | 50.9 (10.77) | 34.26 (12.71) | <0.0001 |
| Total PSQI | 15.82 (3.4) | 14.75 (2.94) | 8.33 (2.78) | <0.0001 |
| Physical functioning | 12.82 (8.82) | 31.27 (12.75) | 44.39 (16.79) | <0.0001 |
| Bodily pain | 6.3 (7.77) | 17.95 (11.79) | 31.45 (11.83) | <0.0001 |
| Size | 94 | 107 | 49 |
Standard deviation values are shown in parentheses.