CFS symptom severity scores for Cohort 2. Symptom severities were scored on ordinal scales from 0 to 4. HC (red columns) had significantly lower scores for each item (mean; 95% C.I. error bars) compared to all CFS (yellow columns) (p ≤ 0.006 after Bonferonni corrections). HC scores were also significantly lower than all the CFS headache subtypes and items except sore throat in CFS+T (green bar). CFS+MA (blue columns) had significantly higher scores than CFS+T for exertional exhaustion (p = 0.036) and sore lymph nodes (p = 0.017).