Method 1 – 1997 Wichita method | Method 2 – 2004 Georgia method | |
---|---|---|
Fatigue | Telephone interview – “Severe fatigue, extreme tiredness, or exhaustion” - Duration 6 months or longer “Yes” AND - Rest makes fatigue a lot better “No” OR “Yes” – Some of the time, a little of the time, or hardly ever | Duration 6 months or longer AND MFI-20 General Fatigue ≥13 OR MFI-20 Reduced Activity ≥10 |
Functional Impairment | Telephone interview – “Yes” to one: “Has this severe fatigue, extreme tiredness or exhaustion substantially limited … …your ability to do your usual job or occupation? …your ability to do your usual educational activities …substantially limited your social, leisure or recreational activities?” | SF-36 v2 Physical Function ≤70 OR Role Physical ≤50 OR Social Function ≤75 OR Role Emotional ≤66.7 |
4 of 8 Case Defining Symptomsa | During the past month how often have you had < SYMPTOM > − “All the time” OR “Most of the time” AND Was < SYMPTOM > bothering you 6 months or longer – “Yes” | CDC Symptom Inventory <SYMPTOM > frequency X intensity scores summed for 8 case defining symptoms ≥25 and scores for at least 4 symptoms |