Table 5.

Limitations of included studies.

#	Study limitation	References
1	Small sample size	[24, 25, 27, 30, 32, 33, 35, 37, 39–42, 44]
2	Lack of or short duration of follow-up	[16, 24, 29, 30, 37, 46, 48]
3	Risk of selection bias	[27, 35, 37, 39, 39, 40]
4	large number of dropouts	[24, 29–31, 48]
5	Lack of measure of all variables in the present study	[35, 38, 44, 46]
6	Generalizability limitation	[28, 32, 35, 37]
7	Using of nonvalidated measure tool	[25, 28, 37]
8	Single blinded or not blinded	[33, 48]
9	Single-center study	[28, 32]
10	Heterogeneity of groups	[27, 46]
11	The possibility of a negative impact of the confounders on the results	[26, 32]
12	Use of inappropriate VR device	[28]
13	Difficulty to monitor the adherence to the exercise program	[40]
14	Using of a subjective assessment tool	[42]