4.3 Correlation values of both scales
The highest correlation was found between similar subdimensions of the
scales namely between SF-36 Physical Functioning and SSQOL Physical
Activities. This result shows that both subdimensions physically
evaluate HRQOL in stroke patients using the same criteria. The weakest
correlation between SF-36 Mental Health and SSQOL-Mood subdimensions may
be related to the expressions of happiness-unhappiness included in the
Mental Health dimension. In contrast to the findings in our study, in a
study where WHOQOL-BREF and SSQOL were compared, a significant
relationship was reported between Psychological Health (PSH) domain of
WHOQOL-BREF and the Thinking subdimension of SSQOL31.
Similarly, in a study comparing SF-36 with another stroke-specific scale
(Stroke Impact Scale: SIS), in contrast to our study, it was reported
that SIS assessed physical, and social functioning better than SF-36,
and use of the items that measures these parameters in SF-36 was not
appropriate for stroke patients17.
A moderate positive correlation found between the total score of the
SSQOL scale and all subdimensions of SF-36, indicates that both scales
could be used to assess quality of life in stroke. However, in general,
the average scores of the SSQOL scale were higher relative to SF-36
scale, which could be interpreted as SSQOL being more appropriate for
these patients. In addition, since the items of the disease-specific
scales better describe the disease in question, use of disease-specific
scales has been recommended in these studies17.