Table 3

Conformity of prevalence estimates in studies where patients diagnosed with CFS/ME with one set of diagnostic criteria are diagnosed sequentially with other case definitions (model B)

Study recruitmentCase definitionsConformity* (95% CI)Symptom and burden profile
Brimacombe et al,69 USA
Fukuda-positive from register
Fukuda† (n=200)
Holmes (n=171)
1
0.85 (0.80 to 0.90)
(F+/H–) patients do not endorse infectious-type symptoms as often or to the same degree of severity as (F+/H+) patients
Jason et al,70 USA
Fukuda-positive from register
Fukuda† (n=32)
Holmes (n=14)
1
0.44 (0.26 to 0.62)
(F+/H+) patients with more symptoms and functional impairment than (F+/H–). No difference in psychological comorbidity
Jason et al,52 USA
Fukuda-positive from register
Fukuda† (n=32)
Canada (n=23)‡
1
0.63 (0.44 to 0.79)
C+ patients have less psychiatric comorbidity, more physical function impairment, are more fatigued with more neurological symptoms than (F+/C–) patients
Jason et al,33 USA
Fukuda-positive recruited from many sources
Fukuda† (n=113)
Canada (n=57)
ME-2011 (n=27)
1
0.50 (0.41 to 0.60)
0.24 (0.16 to 0.33)
(F+/C+) patients had more functional impairments, and physical, mental and cognitive problems than (F+/C–) patients. (F+/ME+) patients had more functional impairments, and more severe physical and cognitive symptoms than (F+/ME–) patients
Fluge et al,9 Norway
Fukuda-positive patients recruited to trial
Fukuda† (n=30)
Canada (n=28)
1
0.93 (0.78 to 0.99)
Not reported
Jason et al,71 USA
Register
Fukuda† (n=24)
Reeves empirical
Canada
Of 24 F+ and 84 F-patients empirical criteria and Canada identified 79 and 87% correctlyCanadia-2003 case definition appears to select more cardinal and central features of the illness than Empirical CDC-2005/Reeves case definition
Jason et al,65 USA
Register
Fukuda† (n=27)
Reeves emp. (n=41)§
1
1.00 (0.87 to 1.00)
Empirical CDC-2005/Reeves case definition led to misclassification of major depressive disorder as CFS
Brown et al,53 USA
Fukuda-positive recruited from many sources
Fukuda† (n=113)
ICC (n=39)

1
0.35 (0.26 to 0.44)
ICC+ patients with more functional impairments and physical, mental and cognitive problems than (F+/ICC–) patients. The ICC+ patients also had greater rates of psychiatric comorbidity
Jason et al,72 USA
Fukuda-positive from register
Fukuda† (n=32)
Dowsett (n=17)¶
1
0.44 (0.26 to 0.62)
D+ patients appear to be more symptomatic than (F+/D–) patients, especially in the neurological and neuropsychiatric areas
White et al,60 UK
Oxford-positive patients recruited to trial
Oxford† (n=641)
Fukuda (n=427)
London ME (n=329)
1
0.67 (0.63 to 0.70)
0.51 (0.47 to 0.55)
Effect of CBT and GET similar regardless of diagnostic group affiliation
Wearden et al,73 UK
Oxford-positive patients recruited to trial
Oxford† (n=296)
London ME (n=92)
1
0.31 (0.26 to 0.37)
Not reported
Stubhaug et al,74 Norway
Neurasthenia-positive patients recruited to trial
Neurasthenia† (n=72)
Oxford (n=65)
Fukuda (n=29)
1
0.90 (0.81 to 0.96), 0.40 (0.29 to 0.53)
Not reported
  • *The proportion of cases relative to the evaluation standard.

  • †Evaluation standard.

  • ‡Three of the 23 participants who tested positive according to the Canada criteria were negative according to Fukuda.

  • §14 of the 37 patients who tested positive according to Reeves were negative according to Fukuda (these 14 patients had a depression diagnosis).

  • ¶Three of the 17 participants who tested positive according to Dowsett were negative according to Fukuda.

  • CBT, cognitive behavorial therapy; CFS, chronic fatigue syndrome; GET, graded exercise therapy; ICC, International Consensus Criteria; ME, myalgic encephalomyelitis.