Table II.

Jadad score to evaluate the quality of included studies

Author, year [reference]	Randomization	Double-blind	Withdrawal and dropout	Total score
Crofford et al., 2005 [25]	2	1	1	4
Arnold et al., 2008 [24]	2	2	1	5
Mease et al., 2008 [23]	1	1	1	3
Paure et al., 2011 [26]	1	1	1	3