Treatment of Fibromyalgia Syndrome: Recommendations of Recent Evidence-Based Interdisciplinary Guidelines with Special Emphasis on Complementary and Alternative Therapies
Table 1
Levels of evidence according to the Oxford Center of Evidence-Based Medicine [7].
Level
Therapy/prevention, aetiology/harm
1a
SR (with homogeneity*) of RCTs
1b
Individual RCT (with narrow Confidence Interval)
1c
All or none
2a
SR (with homogeneity*) of cohort studies
2b
Individual cohort study (including low quality RCT; e.g., <80% followup)
2c
“Outcomes” research; ecological studies
3a
SR (with homogeneity*) of case-control studies
3b
Individual case-control study
4
Case-series (and poor quality cohort and case-control studies)
5
Expert opinion without explicit critical appraisal, or based on physiology, bench research, or “first principles”
