The BBS is a special assessment measure in MS patients [21]. The
BBS is a clinical scale that evaluates balance in sitting and standing
positions and rates various kinds of physical performances from
0 (no performance at all) to 4 (normal performance) [2]. This scale
has 14 items, including sitting to standing, standing unsupported,
sitting unsupported, standing to sitting, transfers, standing with
eyes closed, standing with feet together, reaching forward with
outstretched arm, retrieving objects from the floor, turning to look
behind, turning 360 degrees, placing alternate foot on stool,
standing with one foot in front (Tandem Stance) and standing on
one foot. The maximum score in this scale is 56 [10]. The reliability
of this instrument has been evaluated and confirmed in several
studies [21] and it has also been validated for use in people with MS
[2]. In this study, the BBS form was first translated to Persian language
and then face and content validity of the translated version of
the form were confirmed based on Lawshe's Content Validity Ratio
(CVR) by experts' opinions (11 faculties reviewed and confirmed
the item validity by CVR ¼ 0.802). Internal consistency was
confirmed by Coronbach's Alpha (0.78).