Table 1: Demographic and clinical characteristics of the three groups mean: (standard deviation).

RRMS
n=15
SPMS
n=12
CG
n=12
Gender (Women) 12 (80%) 9 (75%) 9 (75%)
Age (in Years) 43.60
(9.74)
48.67
(8.07)
41.00
(3.34)
Years of Education 11.67
(2.61)
11.75
(3.36)
13.08
(1.50)
Disease Duration 9.20
(3.70)
18.42
(5.82)
WASI Vocabulary Scale T-score 41.50 42.10
EDSS Median (Range) 3.5
(1.5 – 4.0)
6.25
(6.0 -7.5)
FSS 4.02
(1.35)
4.80
(1.80)
BDI-FS 3.67
(2.45)
3.80
(2.46)

RRMS= Relapsing Remitting Multiple Sclerosis; SPMS = Secondary Progressive Multiple Sclerosis; CG= Healthy control group; EDSS = Expanded Disability Status Scale; FSS = Fatigue Severity Scale; BDI-FS = Beck Depression Inventory –Fast Screen; WASI = Wechsler abbreviated Scale of Intelligence
Note: Intelligence level was estimated by administering the vocabulary and matrix reasoning subscales of the Wechsler abbreviated scale of intelligence (WASI), Greek adapted version (Messinis et al., 2009). The vocabulary subscale is a good measure of crystallized intelligence, correlates well with general intellectual ability and is relatively insensitive to cortical insults (i.e., a good measure of premorbid intellectual ability). The matrix reasoning subscale is a measure of nonverbal fluid reasoning and correlates well with general intellectual ability. These two subscales yield an estimated full-scale IQ
All variables investigated for normality with the Shapiro-Wilk test, were normally distributed, p < 0.05, except EDSS which was not normally distributed, p .> 0.05