RESULTS
Data analysis was conducted using the Statistical Package for Social Sciences (SPSS) for Microsoft Windows 11.0 software.
Tests conducted included Analysis of Variance (ANOVA), Analysis of Covariance (ANCOVA), and the Students t-test for Independent
Samples. The total alexithymia score and the three individual factors (F1, F2, F3) that make up the score were analyzed using
a two-way ANCOVA. The between factors are group (Control versus Panic Disorder) and gender (Men versus Women) and the covariate
variable is age. Age is used as a covariate in order to control for possible confounding of age with the main effects of group
and gender on the outcome measures.
There
is a significant main effect of the group variable of Control vs. Panic Disorder, (F=13.8, df=1,55, p =0.001) with means of
50.5 and 61.6 respectively. The main effect of gender is not significant (p=0.21), the means for males and females are 58.4
and 53.1 respectively. However, we do obtain a very significant group by gender interaction effect (F=5.8, df=1,55, p=0.02).
The covariate age is also significant (F=4.9, df=1,55, p=0.03) The R-square for the age variable is 0.31. This indicates that
over 30% of the variability in the TAS-20 score can be explained by age differences.
In order to examine the observed
significant group by gender interaction we conducted separate ANCOVAs for each gender using group as the between factor and
age as the covariate. Among the male subjects we do not obtain a significant difference for the group variable (p=0.29). The
means for the Controls and the Panic Disorder Groups are 55.5 and 60.9 respectively. Among the female subjects, we do observe
a very significant effect of the group variable (F=28.3, df =1,24, p=0.0001). The means for the Control and Panic Disorder
groups are 45.5 and 62.7 respectively.
Examining the individual TAS-20 factors revealed a significant group effect for Factor
1 (F1) - (F=19.7, df=1,55, p=0.001) with means of 17.3 and 24.3 for Controls and Panic Disorder groups respectively. The R-square is 0.29 for the age covariate on F1. The group effect
on Factor 1 (F1) is observed to be significant for both Males and Females (p=0.014 and p=0.001 respectively).
For Factor 2 (F2) we do not see a group effect (p=0.10).
However, we do observe a significant gender difference on F2 (F=4.6, df=1,55, p=0.037). The means for the males and females
on F2 are 15.8 and 12.7 respectively. There is also a gender by group interaction effect on F2 (F=5.1, df=1,55, p=.03). As
seen in the T.A.S. and F1, we also observe a significant group effect on F2 in the female subjects (F=13.4, df=1,24, p=0.001),
but not in the male subjects. The covariate age is also significant (F=9.3, df=1,55, p=.004). The R-square is 0.27 for the
age covariate on F2. The means on Factor 2 (F2) are 10.9 and 15.1 for the Control and Panic Disorder groups respectively.
On Factor 3 (F3) we do not observe either group or gender
effects. However a significant group by gender interaction is observed. (F=5.1, df=1,55, p=0.03). The mean score for the females
are 17.5 and 22.1 for the controls and panic disorder groups respectively, resulting in a significant increase of 4.6 points
(F=7.5, df=1,24, p=0.01). While in the males the difference is not significant (p=0.74) with scores of 22.1 and 21.6, a difference
of only 0.5 points. The age covariate is not significant on F3.
