Table 10.

Instrumental functions: Hedge’s g effect sizes for each test, in descending order.

Test name	N studies	N CFS	N controls	Hedges'g	S.E	95% CI	p value	Q	p	I2 (%)	Study references
Language
Boston naming test	2	59	40	0.18	0.20	− 0.219 to 0.579	0.377	0.05	0.83	0.00	Lawrie et al.31, Marcel et al.34
WAIS vocabulary	3	94	87	− 0.19	0.15	− 0.483 to 0.095	0.187	0.95	0.62	0.00	De Luca et al.22, Michiels et al.40, Short et al.49
WAIS-R vocabulary	2	170	101	0.08	0.13	− 0.62 to 0.331	0.501	0.31	0.58	0.00	Busichio et al.12, Marcel et al.34
Calculation
Wais-R Arithmetics	2	58	53	− 0.18	0.19	− 0.550 to 0.187	0.335	0.52	0.47	0.00	Claypoole et al.15, De Luca et al.22
Visuo-construction
Rey Osterreth complexe figure (copy) Cotation 2	3	92	71	− 0.39	0.16	− 0.703 to − 0.084	0.013	1.63	0.44	0.00	De Luca et al.21,22, Tiersky et al.52
Rey Osterreth complexe figure (copy) Cotation 1	3	96	98	− 0.19	0.14	− 0.470 to 0.090	0.184	3.53	0.17	43.36	Claypoole et al.15, Short et al.49, Vercoulen et al.54
WAIS-R blocks	3	193	113	− 0.07	0.12	− 0.305 to 0.159	0.537	0.05	0.98	0.00	Busichio et al. (2001); Claypoole et al.15, Lawrie et al.31

WAIS Wechsler adult intelligence scale, ME/CFS myalgic encephalomyelitis/chronic fatigue syndrome, N number.