Jadad Scale for the 17 randomized controlled studies.

ITT: intention-to-treat. A: adequate, with correct procedure; B: unclear, without a description of the methods; C: inadequate procedures, methods, or information. Each criterion was graded as follows: Yes, adequate, with correct procedure; Unclear, without a description of the methods; No, inadequate procedures, methods, or information. Each involved study was graded as follows: A, studies with a low risk of bias and which were scored as grade of A for all items; B, studies with a moderate risk of bias, with one or more grades of B; and C, studies with a high risk of bias, with one or more grades of C. Jadad Scale for the 17 randomized controlled studies.